The human immunodeficiency virus 1 (HIV-1) still remains one of the leading life-threatening dise... more The human immunodeficiency virus 1 (HIV-1) still remains one of the leading life-threatening diseases in the world. The introduction of highly active antiretroviral therapy has significantly reduced disease morbidity and mortality. However, most of the drugs have variable penetrance into viral reservoir sites, including gut-associated lymphoid tissue (GALT). Being the largest lymphoid organ, GALT plays a key role in early HIV infection and host–pathogen interaction. Many different treatment options have been proposed to eradicate the virus from GALT. However, it becomes difficult to deliver traditional drugs to the GALT because of its complex physiology. In this regard, we developed a polymer-based Pluronic nanocarrier containing anti-HIV drug called efavirenz (EFV) targeting Microfold cells (M-cells) in the GALT. M-cells are specialized epithelial cells that are predominantly present in the GALT. In this work, we have exploited this paracellular transport property of M-cells for targeted delivery of Pluronic nanocarrier tagged EFV, bioconjugated with anti-M-cell-specific antibodies to the GALT (nano-drug). Preliminary characterization showed that the nanodrug (EFV-F12-COOH) is of 140 nm size with 0.3 polydispersion index, and the zeta potential of the particles was −19.38±2.2 mV. Further, drug dissolution study has shown a significantly improved sustained release over free drugs. Binding potential of nanodrug with M-cell was also confirmed with fluorescence microscopy and in vitro uptake and release studies. The anti-HIV activity of the nanodrug was also significantly higher compared to that of free drug. This novel formulation was able to show sustained release of EFV and inhibit the HIV-1 infection in the GALT compared to the free drug. The present study has potential for our in vivo targeted nanodrug delivery system by combining traditional enteric-coated capsule technique via oral administration.
Background: HIV-associated neurological disorder (HAND) has long been recognized as a consequence... more Background: HIV-associated neurological disorder (HAND) has long been recognized as a consequence of human immunodeficiency virus (HIV) infection in the brain. The pathology of HAND gets more complicated with the recreational drug use such as cocaine. Recent studies have suggested multiple genetic influences involved in the pathology of addiction and HAND but only a fraction of the entire genetic risk has been investigated so far. In this regard, role of DJ1 protein (a gene linked to autosomal recessive early-onset Parkinson's disease) in regulating dopamine (DA) transmission and reactive oxygen species (ROS) production in neuronal cells will be worth investigating in HIV-1 and cocaine exposed microenvironment. Being a very abundant protein in the brain, DJ1 could serve as a potential marker for early detection of HIV-1 and/or cocaine related neurological disorder. Methods: In vitro analysis was done to observe the effect of HIV-1 and/or cocaine on DJ1 protein expression in neuroblastoma cells (SK-N-MC). Gene and protein expression analysis of DJ1 was done on the HIV infected and/or cocaine treated SK-N-MC and compared to untreated cells using real time PCR, Western Blot and flow cytometry. Effect of DJ1 dysregulation on oxidative stress was analyzed by measuring ROS production in these cells. Results: Gene expression and protein analysis indicated that there was a significant decrease in DJ1 expression in SK-N-MC chronically exposed to HIV-1 and/or cocaine which is inversely proportional to ROS production. Conclusion: This is the first study to establish that DJ1 expression level in the neuronal cells significantly decreased in presence of HIV-1 and/or cocaine indicating oxidative stress level of DA neurons.
A novel approach was developed for the coencapsulation of an anti-HIV drug (teno-fovir) and a lat... more A novel approach was developed for the coencapsulation of an anti-HIV drug (teno-fovir) and a latency-breaking agent (vorinostat), using magnetically guided layer-by-layer (LbL) assembled nanocarriers for the treatment of neuroAIDS. Ultrasmall iron oxide (Fe 3 O 4) nanopar-ticles (10±3 nm) were synthesized and characterized. The LbL technique was used to achieve a sustained release profile, and application of 2 bilayers ([tenofovir+dextran sulphate] 2 +vorinostat) to magnetic nanoparticles resulted in a 2.8 times increase in drug (tenofovir) loading and also resulted in an increase in the drug release period by 30-fold, with 100% drug release in sustained manner over a period of 5 days with the simultaneous stimulation of latent HIV expression. Nanoformulation showed a good blood–brain barrier transmigration ability (37.95%±1.5%) with good in vitro antiviral efficacy (~33% reduction of p24 level) over a period of 5 days after HIV infection in primary human astrocytes, with good cell viability (.90%). Hence, LbL arrangements of drugs on magnetic nanoparticles provides sustained release and, therefore, may improve the patient's adherence to therapy and lead to better compliance.
Parenteral use of drugs; such as opiates exert immunomodulatory effects and serve as a cofactor i... more Parenteral use of drugs; such as opiates exert immunomodulatory effects and serve as a cofactor in the progression of HIV-1 infection, thereby potentiating HIV related neurotoxicity ultimately leading to progression of NeuroAIDS. Morphine exposure is known to induce apoptosis, down regulate cAMP response element-binding (CREB) expression and decrease in dendritic branching and spine density in cultured cells. Use of neuroprotective agent; brain derived neurotropic factor (BDNF), which protects neurons against these effects, could be of therapeutic benefit in the treatment of opiate addiction. Previous studies have shown that BDNF was not transported through the blood brain barrier (BBB) in-vivo.; and hence it is not effective in-vivo. Therefore development of a drug delivery system that can cross BBB may have significant therapeutic advantage. In the present study, we hypothesized that magnetically guided nanocarrier may provide a viable approach for targeting BDNF across the BBB. We developed a magnetic nanoparticle (MNP) based carrier bound to BDNF and evaluated its efficacy and ability to transmigrate across the BBB using an in-vitro BBB model. The end point determinations of BDNF that crossed BBB were apoptosis, CREB expression and dendritic spine density measurement. We found that transmigrated BDNF was effective in suppressing the morphine induced apoptosis, inducing CREB expression and restoring the spine density. Our results suggest that the developed nanocarrier will provide a potential therapeutic approach to treat opiate addiction, protect neurotoxicity and synaptic density degeneration.
Background: Although highly active antiretroviral therapy (HAART) has significantly reduced the m... more Background: Although highly active antiretroviral therapy (HAART) has significantly reduced the morbidity and mortality in HIV patients, virus continues to reside in the central nervous system (CNS) reservoir. Hence, a complete eradication of virus remains a challenge. HIV productively infects microglia/macrophages, but astrocytes are generally restricted to HIV infection. The relative importance of the possible replication blocks in astrocytes, however, is yet to be delineated. A recently identified restriction factor, sterile alpha motif and histidine/aspartic acid domain-containing protein 1 (SAMHD1), restricts HIV infection in resting CD4 + T cells and in monocyte-derived dendritic cells. However, SAMHD1 expression and HIV-1 restriction activity regulation in the CNS cells are unknown. Though, certain miRNAs have been implicated in HIV restriction in resting CD4 + T cells, their role in the CNS HIV restriction and their mode of action are not established. We hypothesized that varying SAMHD1 expression would lead to restricted HIV infection and host miRNAs would regulate SAMHD1 expression in astrocytes. Results: We found increased SAMHD1 expression and decreased miRNA expression (miR-181a and miR-155) in the astrocytes compared to microglia. We report for the first time that miR-155 and miR-181a regulated the SAMHD1 expression. Overexpression of these cellular miRNAs increased viral replication in the astrocytes, through SAMHD1 modulation. Reactivation of HIV replication was accompanied by decrease in SAMHD1 expression.
Previous studies have shown that, during infection, HIV-1 clade B and clade C differentially cont... more Previous studies have shown that, during infection, HIV-1 clade B and clade C differentially contribute to the neuropathogenesis and development of HIV-associated neurocognitive disorders (HANDs). The low-molecular-weight tripeptide glutathione (GSH) alters the redox balance and leads to the generation of reactive oxygen species, which play a significant role in the neuropathogenesis of HANDs. We hypothesized that the HIV-1 clade B and clade C viruses and their respective Tat proteins exert differential effects on monocyte-derived immature dendritic cells (IDCs) and neuroblastoma cells (SK-N-MC) by redox activation, which leads to immunoneuropathogenesis. The GSH/GSSG ratio and mRNA expression levels and protein modification of glutathione synthetase (GSS), glutathione perox-idase 1 (GPx1), superoxide dismutase 1 (SOD1), and catalase (CAT) were analyzed in IDCs infected with HIV-1 clade B or clade C as well as in cells treated with the respective Tat proteins. The results indicated that HIV-1 clade B virus and its Tat protein significantly increased the production of reactive oxygen species and reduced the GSH/GSSG ratio and subsequent downregulation of gene expression and protein modification of GSS, GPx1, SOD1, and CAT compared to infection with the clade C virus or treatment with the clade C Tat protein. Thus, our studies demonstrate that HIV-1 clades B and C exert differential effects of redox expression and thiol modification. HIV-1 clade B potentially induces oxidative stress, leading to more immunoneuropathogenesis than infection with HIV-1 clade C.
HIV subtypes or clades differentially induce HIV-associated neurocognitive disorders (HAND) and s... more HIV subtypes or clades differentially induce HIV-associated neurocognitive disorders (HAND) and substance abuse is known to accelerate HIV disease progression. The HIV-1 envelope protein gp120 plays a major role in binding and budding in the central nervous system (CNS) and impacts dopaminergic functions. However, the mechanisms utilized by HIV-1 clades to exert differential effects and the methamphetamine (METH)-associated dopaminergic dysfunction are poorly understood. We hypothesized that clade B and C gp120 structural sequences, modeling based analysis, dopaminergic effect, and METH potentiate neuronal toxicity in astrocytes. We evaluated the effect of clade B and C gp120 and/or METH on the DRD-2, DAT, CaMKs and CREBP transcription. Both the structural sequence and modeling studies demonstrated that clade B gp120 in V1-V4, α-2 and N-glycosylated sites are distinct from clade C gp120. The distinct structure and sequence variation of clade B gp120 differentially impact DRD-2, DAT, CaMK II and CaMK IV mRNA, protein and intracellular expression compared to clade C gp120. However, CREB transcription is upregulated by both clade B and C gp120, and METH co-treatment potentiated these effects. In conclusion, distinct structural sequences of HIV-1 clade B and C gp120 differentially regulate the dopaminergic pathway and METH potentiates neurotoxicity. HIV-1 infection causes immune dysfunction and is a risk factor in the neuropathogenesis of brain disease 1. HIV-infected brain cells secrete inflammatory cytokines, chemokines and neurotoxic factors that alter amino acid metabolism and neurotransmitter systems, including dopamine, acetylcholine and ser-otonin. However, HIV infection has a significant effect on dopamine 2–5. Clinical observations suggest that patients with HIV-associated neurocognitive disorders (HAND) may have dopamine deficits associated with cognitive dysfunctions 6,7. HIV infection alters intracellular Ca 2+ , affecting dopamine levels, dopamine receptors (DRD) and the dopamine transporter (DAT) 8,9. In addition, calcium influx exerts its effects on the ubiquitous Ca 2+ sensor, including the calcium/ calmodulin-dependent protein kinases CaMK II and CaMK IV 10,11 , which affect the cyclic response element binding protein (CREBP) 12,13. Collectively, dopaminergic systems may be vulnerable to the effects of HIV infection in the brain.
HIV infection and illicit drugs are known to induce oxidative stress and linked with severity of ... more HIV infection and illicit drugs are known to induce oxidative stress and linked with severity of viral replication, disease progression, impaired cell cycle regulation and neurodegeneration. Studies have shown that morphine accelerates HIV infection and disease progression mediated by Reactive oxygen species (ROS). Oxidative stress impact redox balance and ROS production affect cell cycle regulation. However, the role of morphine in HIV associated acceleration of oxidative stress and its link to cell cycle regulation and neurodegeneration has not been elucidated. The aim of present study is to elucidate the mechanism of oxidative stress induced glutathione synthases (GSS), super oxide dismutase (SOD), and glutathione peroxidase (GPx) impact cell cycle regulated protein cyclin-dependent kinase 1, cell division cycle 2 (CDK-1/CDC-2), cyclin B, and cell division cycle 25C (CDC-25C) influencing neuronal dysfunction by morphine co-morbidity with HIV-1 gp120. It was observed that redox imbalance inhibited the GSS, GPx and increased SOD which, subsequently inhibited CDK-1/CDC-2 whereas cyclin B and CDC-25C significantly up regulated in HIV-1 gp120 with morphine compared to either HIV-1 gp120 or morphine treated alone in human microglial cell line. These results suggest that HIV positive morphine users have increased levels of oxidative stress and effect of cell cycle machinery, which may cause the HIV infection and disease progression.
Leishmania are obligate intracellular protozoan parasites of mammalian hosts. Promastigotes of Le... more Leishmania are obligate intracellular protozoan parasites of mammalian hosts. Promastigotes of Leishmania are internalized by macrophages and transformed into amastigotes in phagosomes, and replicate in phagolysosomes. Phagosomal maturation arrest is known to play a crucial role in the survival of pathogenic Leishmania within activated macrophages. Recently, tryptophan–aspartate containing coat (TACO) gene has been recognized as playing a central role in the survival of Mycobacterium tuberculosis within human macrophages by arresting the phagosome maturation process. We postulated that a similar association of TACO gene with phagosomes would prevent the vacuole from maturation in the case of Leishmania. In this study we attempted to define the effect of TACO gene downregulation on the entry/survival of Leishmania donovani intracellularly, by treatment with Vitamin D 3 (Vit.D 3)/Retinoic acid (RA) and chenodeoxycholic acid (CDCA)/RA combinations in human THP-1 macrophages (in vitro). Treatment with these molecules downregulated the TACO gene in macrophages, resulting in reduced parasite load and marked reduction of disease progression in L. donovani infected macrophages. Taken together, these results suggest that TACO gene downregulation may play a role in subverting macrophage machinery in establishing the L. donovani replicative niche inside the host. Our study is the first to highlight the important role of the TACO gene in Leishmania entry, survival and to identify TACO gene downregulation as potential drug target against leishmaniasis.
The nanotechnology capable of high-specificity targeted delivery of anti-neoplastic drugs would b... more The nanotechnology capable of high-specificity targeted delivery of anti-neoplastic drugs would be a significant breakthrough in Cancer in general and Ovarian Cancer in particular. We addressed this challenge through a new physical concept that exploited (i) the difference in the membrane electric properties between the tumor and healthy cells and (ii) the capability of magneto-electric nanoparticles (MENs) to serve as nanosized converters of remote magnetic field energy into the MENs' intrinsic electric field energy. This capability allows to remotely control the membrane electric fields and consequently trigger high-specificity drug uptake through creation of localized nano-electroporation sites. In in-vitro studies on human ovarian carcinoma cell (SKOV-3) and healthy cell (HOMEC) lines, we applied a 30-Oe d.c. field to trigger high-specificity uptake of paclitaxel loaded on 30-nm CoFe 2 O 4 @BaTiO 3 MENs. The drug penetrated through the membrane and completely eradicated the tumor within 24 hours without affecting the normal cells. T he development of a technology that is capable of high-specificity targeted delivery of anti-neoplastic drugs would be a significant breakthrough in cancer in general and ovarian cancer in particular. Although the circulatory system can deliver a drug to every cell in the body, delivering the drug specifically inside the tumor cell past its membrane without affecting the healthy cells remains a challenge 1–3. In ovarian cancer, intraperitoneal (IP) delivery through a surgically implanted catheter has shown improved survival rates. However, catheter complications and toxicity have precluded widespread adoption of this invasive means of delivery 4. Current research attempts to go around these limiting factors by using nanoscale systems 5–7. Often, as immunological reagents, monoclonal antibodies are used to recognize the tumor-specific biomarker while the nanoscale control further improves the specificity and targeted drug delivery capability in general 8–10. Nonetheless, in spite of the tremendous progress in this field during the last decades, the capability of targeted delivery with adequately high specificity (to tumor cells) remains an important roadblock to finding a cure for cancer. In this paper, we present a study in which we address this challenge through a new physical concept. It exploits (i) the difference in the electric properties of the membrane between the tumor and healthy cells and (ii) the ability of the recently discovered body-temperature magneto-electric nanoparticles (MENs) to function as nano-converters of remotely supplied magnetic field energy into the MENs' intrinsic electric field energy 11–13. Like the conventional magnetic nanoparticles (MNs), MENs have a non-zero magnetic moment and therefore can be controlled remotely via application of an external magnetic field. However, unlike MNs, MENs offer a new far-reaching function, which is an energy-efficient control of the intrinsic electric fields within the nanoparticles by an external magnetic field. This unprecedented capability is a result of the strong magneto-electric (ME) coupling in this new class of nanostructures even at body temperature 11–13. As a result, MENs introduced in a biological microenvironment act as localized magnetic-to-electric-field nano-converters that allow remote control and generation of the electric signals that underlie the intrinsic molecular interactions. Recently, we exploited this
Based on the type of cells or tissues they tend to harbor or attack, many of the viruses are char... more Based on the type of cells or tissues they tend to harbor or attack, many of the viruses are characterized. But, in case of neurotropic viruses, it is not possible to classify them based on their tropism because many of them are not primarily neurotropic. While rabies and poliovirus are considered as strictly neurotropic, other neurotropic viruses involve nervous tissue only secondarily. Since the AIDS pandemic, the interest in neurotropic viral infections has become essential for all clinical neurologists. Although these neurotropic viruses are able to be harbored in or infect the nervous system, not all the neurotropic viruses have been reported to cause disrupted synaptic plasticity and impaired cognitive functions. In this review, we have discussed the neurotropic viruses, which play a major role in altered synaptic plasticity and neurological disorders.
As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) per... more As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) persists to rise, effective drug treatments are required to treat the infected people. Even though combination antiretroviral therapy (cART) provides stable viral suppression, it is not devoid of undesirable side effects, especially in persons undergoing long-term treatment. The present therapy finds its limitations in the emergence of multidrug resistance and accordingly finding new drugs and novel targets is the need of the hour to treat the infected persons and further to attack HIV reservoirs in the body like brain, lymph nodes to achieve the ultimate goal of complete eradication of HIV and AIDS. Natural products such as plant-originated compounds and plant extracts have enormous potential to become drug leads with anti-HIV and neuroprotective activity. Accordingly, many research groups are exploring the biodiversity of the plant kingdom to find new and better anti-HIV drugs with novel mechanisms of action and for HIV-associated neurocognitive disorders (HAND). The basic challenge that still persists is to develop viral replication-targeted therapy using novel anti-HIV compounds with new mode of action, accepted toxicity and less resistance profile. Against this backdrop, the World Health Organization (WHO) suggested the need to evaluate ethno-medicines for the management of HIV/AIDS. Consequently, there is need to evaluate traditional medicine, particularly medicinal plants and other natural products that may yield effective and affordable therapeutic agents. Although there are a good number of reports on traditional uses of plants to treat various diseases, knowledge of herbal remedies used to manage HIV/AIDS and HAND are scanty, vague and not well documented. In this review, plant substances showing a promising action that is anti-HIV and HAND will be explored along with what they interact. Since some plant substances are also known to modulate several cellular factors which are also involved in the replication of HIV and hence their role as potential candidates will be discussed. HIV/AIDS being an exceptional epidemic, demands an exceptional approach and that forms very much focus for the current review.
During human immunodeficiency virus (HIV) infection, alcohol has been known to induce inflammatio... more During human immunodeficiency virus (HIV) infection, alcohol has been known to induce inflammation while cannabinoids have been shown to have an anti-inflammatory role. For instance cannabinoids have been shown to reduce susceptibility to HIV-1 infection and attenuate HIV replication in macrophages. Recently, we demonstrated that alcohol induces cannabinoid receptors and regulates cytokine production by monocyte-derived dendritic cells (MDDC). However, the ability of alcohol and cannabinoids to alter MDDC function during HIV infection has not been clearly elucidated yet. In order to study the potential impact of alcohol and cannabinoids on differentiated MDDC infected with HIV, monocytes were cultured for 7 days with GM-CSF and IL-4, differentiated MDDC were infected with HIV-1Ba-L and treated with EtOH (0.1 and 0.2%), THC (5 and 10 μM), or JWH-015 (5 and 10 μM) for 4–7 days. HIV infection of MDDC was confirmed by p24 and Long Terminal Repeats (LTR) estimation. MDDC endocytosis assay and cytokine array profiles were measured to investigate the effects of HIV and substances of abuse on MDDC function. Our results show the HIV + EtOH treated MDDC had the highest levels of p24 production and expression when compared with the HIV positive controls and the cannabinoid treated cells. Although both cannabinoids, THC and JWH-015 had lower levels of p24 production and expression, the HIV + JWH-015 treated MDDC had the lowest levels of p24 when compared to the HIV + THC treated cells. In addition, MDDC endocytic function and cytokine production were also differentially altered after alcohol and cannabinoid treatments. Our results show a differential effect of alcohol and cannabinoids, which may provide insights into the divergent inflammatory role of alcohol and cannabinoids to modulate MDDC function in the context of HIV infection.
Methicillin Resistant Staphylococcus aureus (MRSA) has emerged as a major hospital pathogen. Howe... more Methicillin Resistant Staphylococcus aureus (MRSA) has emerged as a major hospital pathogen. However studies from India between 1994-2001, reported the incidence of MRSA between 32.8%-51.6%. In recent years, there have been several reports of community-associated MRSA (CA-MRSA) infections throughout the world. The present study was aimed at the epidemiological survey of methicillin resistant S. aureus in the community and hospital. Samples were collected from hospital (202 samples from staff and patients, 50 samples from operation theatres and ICU) and environmental groups (Swabs from nose and axilla were collected from 70 children and 56 adults). The samples were tested for the presence MRSA. Staphylococci was isolated from 55 (30 from children and 25 from adults) samples from community group where as in 37 samples collected from the various groups of people in the hospital and none from the environment i.e. operation theater and ICU. The S. aureus isolates were studied for methicillin resistance by testing the sensitivity of the isolate to Oxacillin. Of the 26 isolates tested of S. aureus from the community (11 from children and 15 from adults), no MRSA was found. In the hospital, out of the 15 S. aureus isolates, five (33.3%) were confirmed as MRSA. Thus this study shows a prevalence of 33.3% of MRSA in hospital specimens collected from patients, and no carrier state among hospital staff or in the environments. The specimen collected from the community did not show any MRSA. It is possible that CA-MRSA has not yet established in the community studied in the present work at the present time. Further surveillance studies are necessary to continuously monitor the presence of CA-MRSA to alert the clinicians to prevent the serious complications.
The blood-brain barrier (BBB) is considered as the primary impediment barrier for most drugs. Del... more The blood-brain barrier (BBB) is considered as the primary impediment barrier for most drugs. Delivering therapeutic agents to the brain is still a big challenge to date. In our study, a dual mechanism, receptor mediation combined with external non-invasive magnetic force, was incorporated into ferrous magnet-based liposomes for BBB transmigration enhancement. The homogenous magnetic nanoparticles (MNPs), with a size of ∼10 nm, were synthesized and confirmed by TEM and XRD respectively. The classical magnetism assay showed the presence of the characteristic superparamagnetic property. These MNPs encapsulated in PEGylated fluorescent liposomes as magneto-liposomes (MLs) showed mono-dispersion, ∼130 ± 10 nm diameter, by dynamic laser scattering (DLS) using the lipid-extrusion technique. Remarkably, a magnetite encapsulation efficiency of nearly 60% was achieved. Moreover, the luminescence and hydrodynamic size of the MLs was stable for over two months at 4 • C. Additionally, the integrity of the ML structure remained unaffected through 120 rounds of circulation mimicking human blood fluid. After biocompatibility confirmation by cytotoxicity evaluation, these fluorescent MLs were further embedded with transferrin and applied to an in vitro BBB transmigration study in the presence or absence of external magnetic force. Comparing with magnetic force-or transferrin receptor-mediated transportation alone, their synergy resulted in 50-100% increased transmigration without affecting the BBB integrity. Consequently, confocal microscopy and iron concentration in BBB-composed cells further confirmed the higher cellular uptake of ML particles due to the synergic effect. Thus, our multifunctional liposomal magnetic nanocarriers possess great potential in particle transmigration across the BBB and may have a bright future in drug delivery to the brain.
Serum and urine samples were collected from 33 NCC patients before the albendazole treatment, 3–6... more Serum and urine samples were collected from 33 NCC patients before the albendazole treatment, 3–6 and 12 months PT. At 3 months PT, 24 (72.7%) patients had no detectable CT/MRI lesions and 9 (27.2%) patients had persistent lesions. Antibody response to crude soluble extract (CSE), excretory secretory (ES), and lower molecular mass (LMM) (10–30 KDa) antigenic fraction of T. solium cysticerci was detected in serum and urine samples by ELISA. Before the treatment, out of 33 NCC children, 14 (42.4%), 22 (66.6%), and 11 (33.3%) serum samples were found positive with the use of CSE, ES, and LMM antigen, respectively. At 3–6 months PT, positivity rate was 5 (15.1%), 2 (6%), and 4 (12.1%) and at 12 months PT, positivity rate was 5 (15.1%), 0, and 3 (9%) with the use of CSE, ES, and LMM antigen, respectively. There was no significant difference in the positivity with the use of three antigens in pretreatment and PT urine samples. The study suggests that the use of ES antigen to detect antibody in serum samples may serve better purpose to evaluate the therapeutic response in patients with NCC.
To understand HIV pathogenesis or development is no simple undertaking and neither is the cell cy... more To understand HIV pathogenesis or development is no simple undertaking and neither is the cell cycle which is highly complex that requires the coordination of multiple events and machinery. It is interesting that these two processes are interrelated, intersect and interact as HIV-1 infection results in cell cycle arrest at the G2 phase which is accompanied by massive CD4 + T cell death. For its own benefit, in an impressive manner and with the overabundance of tactics, HIV maneuvers DNA damage responses and cell cycle check points for viral replication at different stages from infection, to latency and to patho-genesis. Although the cell cycle is the most critical aspect involved in both viral and cellular replication, in this review, our main focus is on recent developments, including our own observations in the field of cell cycle proteins , checkpoints and strategies utilized by the viruses to manipulate these pathways to promote their own rep-lication and survival. We will also discuss the emerging concept of targeting the replication initiation machinery for HIV therapy.
The blood-brain barrier (BBB) is a diffusion barrier that has an important role in maintaining a ... more The blood-brain barrier (BBB) is a diffusion barrier that has an important role in maintaining a precisely regulated microenvironment protecting the neural tissue from infectious agents and toxins in the circulating system. Compromised BBB integrity plays a major role in the pathogenesis of retroviral associated neurological diseases. Human Immunodeficiency Virus (HIV) infection in the Central Nervous System (CNS) is an early event even before the serodiagnosis for HIV positivity or the initiation of antiretroviral therapy (ART), resulting in neurological complications in many of the infected patients. Macrophages, microglia and astrocytes (in low levels) are the most productively/latently infected cell types within the CNS. In this brief review, we have discussed about the effect of HIV infection and viral proteins on the integrity and function of BBB, which may contribute to the progression of HIV associated neurocognitive disorders.
The human immunodeficiency virus 1 (HIV-1) still remains one of the leading life-threatening dise... more The human immunodeficiency virus 1 (HIV-1) still remains one of the leading life-threatening diseases in the world. The introduction of highly active antiretroviral therapy has significantly reduced disease morbidity and mortality. However, most of the drugs have variable penetrance into viral reservoir sites, including gut-associated lymphoid tissue (GALT). Being the largest lymphoid organ, GALT plays a key role in early HIV infection and host–pathogen interaction. Many different treatment options have been proposed to eradicate the virus from GALT. However, it becomes difficult to deliver traditional drugs to the GALT because of its complex physiology. In this regard, we developed a polymer-based Pluronic nanocarrier containing anti-HIV drug called efavirenz (EFV) targeting Microfold cells (M-cells) in the GALT. M-cells are specialized epithelial cells that are predominantly present in the GALT. In this work, we have exploited this paracellular transport property of M-cells for targeted delivery of Pluronic nanocarrier tagged EFV, bioconjugated with anti-M-cell-specific antibodies to the GALT (nano-drug). Preliminary characterization showed that the nanodrug (EFV-F12-COOH) is of 140 nm size with 0.3 polydispersion index, and the zeta potential of the particles was −19.38±2.2 mV. Further, drug dissolution study has shown a significantly improved sustained release over free drugs. Binding potential of nanodrug with M-cell was also confirmed with fluorescence microscopy and in vitro uptake and release studies. The anti-HIV activity of the nanodrug was also significantly higher compared to that of free drug. This novel formulation was able to show sustained release of EFV and inhibit the HIV-1 infection in the GALT compared to the free drug. The present study has potential for our in vivo targeted nanodrug delivery system by combining traditional enteric-coated capsule technique via oral administration.
Background: HIV-associated neurological disorder (HAND) has long been recognized as a consequence... more Background: HIV-associated neurological disorder (HAND) has long been recognized as a consequence of human immunodeficiency virus (HIV) infection in the brain. The pathology of HAND gets more complicated with the recreational drug use such as cocaine. Recent studies have suggested multiple genetic influences involved in the pathology of addiction and HAND but only a fraction of the entire genetic risk has been investigated so far. In this regard, role of DJ1 protein (a gene linked to autosomal recessive early-onset Parkinson's disease) in regulating dopamine (DA) transmission and reactive oxygen species (ROS) production in neuronal cells will be worth investigating in HIV-1 and cocaine exposed microenvironment. Being a very abundant protein in the brain, DJ1 could serve as a potential marker for early detection of HIV-1 and/or cocaine related neurological disorder. Methods: In vitro analysis was done to observe the effect of HIV-1 and/or cocaine on DJ1 protein expression in neuroblastoma cells (SK-N-MC). Gene and protein expression analysis of DJ1 was done on the HIV infected and/or cocaine treated SK-N-MC and compared to untreated cells using real time PCR, Western Blot and flow cytometry. Effect of DJ1 dysregulation on oxidative stress was analyzed by measuring ROS production in these cells. Results: Gene expression and protein analysis indicated that there was a significant decrease in DJ1 expression in SK-N-MC chronically exposed to HIV-1 and/or cocaine which is inversely proportional to ROS production. Conclusion: This is the first study to establish that DJ1 expression level in the neuronal cells significantly decreased in presence of HIV-1 and/or cocaine indicating oxidative stress level of DA neurons.
A novel approach was developed for the coencapsulation of an anti-HIV drug (teno-fovir) and a lat... more A novel approach was developed for the coencapsulation of an anti-HIV drug (teno-fovir) and a latency-breaking agent (vorinostat), using magnetically guided layer-by-layer (LbL) assembled nanocarriers for the treatment of neuroAIDS. Ultrasmall iron oxide (Fe 3 O 4) nanopar-ticles (10±3 nm) were synthesized and characterized. The LbL technique was used to achieve a sustained release profile, and application of 2 bilayers ([tenofovir+dextran sulphate] 2 +vorinostat) to magnetic nanoparticles resulted in a 2.8 times increase in drug (tenofovir) loading and also resulted in an increase in the drug release period by 30-fold, with 100% drug release in sustained manner over a period of 5 days with the simultaneous stimulation of latent HIV expression. Nanoformulation showed a good blood–brain barrier transmigration ability (37.95%±1.5%) with good in vitro antiviral efficacy (~33% reduction of p24 level) over a period of 5 days after HIV infection in primary human astrocytes, with good cell viability (.90%). Hence, LbL arrangements of drugs on magnetic nanoparticles provides sustained release and, therefore, may improve the patient's adherence to therapy and lead to better compliance.
Parenteral use of drugs; such as opiates exert immunomodulatory effects and serve as a cofactor i... more Parenteral use of drugs; such as opiates exert immunomodulatory effects and serve as a cofactor in the progression of HIV-1 infection, thereby potentiating HIV related neurotoxicity ultimately leading to progression of NeuroAIDS. Morphine exposure is known to induce apoptosis, down regulate cAMP response element-binding (CREB) expression and decrease in dendritic branching and spine density in cultured cells. Use of neuroprotective agent; brain derived neurotropic factor (BDNF), which protects neurons against these effects, could be of therapeutic benefit in the treatment of opiate addiction. Previous studies have shown that BDNF was not transported through the blood brain barrier (BBB) in-vivo.; and hence it is not effective in-vivo. Therefore development of a drug delivery system that can cross BBB may have significant therapeutic advantage. In the present study, we hypothesized that magnetically guided nanocarrier may provide a viable approach for targeting BDNF across the BBB. We developed a magnetic nanoparticle (MNP) based carrier bound to BDNF and evaluated its efficacy and ability to transmigrate across the BBB using an in-vitro BBB model. The end point determinations of BDNF that crossed BBB were apoptosis, CREB expression and dendritic spine density measurement. We found that transmigrated BDNF was effective in suppressing the morphine induced apoptosis, inducing CREB expression and restoring the spine density. Our results suggest that the developed nanocarrier will provide a potential therapeutic approach to treat opiate addiction, protect neurotoxicity and synaptic density degeneration.
Background: Although highly active antiretroviral therapy (HAART) has significantly reduced the m... more Background: Although highly active antiretroviral therapy (HAART) has significantly reduced the morbidity and mortality in HIV patients, virus continues to reside in the central nervous system (CNS) reservoir. Hence, a complete eradication of virus remains a challenge. HIV productively infects microglia/macrophages, but astrocytes are generally restricted to HIV infection. The relative importance of the possible replication blocks in astrocytes, however, is yet to be delineated. A recently identified restriction factor, sterile alpha motif and histidine/aspartic acid domain-containing protein 1 (SAMHD1), restricts HIV infection in resting CD4 + T cells and in monocyte-derived dendritic cells. However, SAMHD1 expression and HIV-1 restriction activity regulation in the CNS cells are unknown. Though, certain miRNAs have been implicated in HIV restriction in resting CD4 + T cells, their role in the CNS HIV restriction and their mode of action are not established. We hypothesized that varying SAMHD1 expression would lead to restricted HIV infection and host miRNAs would regulate SAMHD1 expression in astrocytes. Results: We found increased SAMHD1 expression and decreased miRNA expression (miR-181a and miR-155) in the astrocytes compared to microglia. We report for the first time that miR-155 and miR-181a regulated the SAMHD1 expression. Overexpression of these cellular miRNAs increased viral replication in the astrocytes, through SAMHD1 modulation. Reactivation of HIV replication was accompanied by decrease in SAMHD1 expression.
Previous studies have shown that, during infection, HIV-1 clade B and clade C differentially cont... more Previous studies have shown that, during infection, HIV-1 clade B and clade C differentially contribute to the neuropathogenesis and development of HIV-associated neurocognitive disorders (HANDs). The low-molecular-weight tripeptide glutathione (GSH) alters the redox balance and leads to the generation of reactive oxygen species, which play a significant role in the neuropathogenesis of HANDs. We hypothesized that the HIV-1 clade B and clade C viruses and their respective Tat proteins exert differential effects on monocyte-derived immature dendritic cells (IDCs) and neuroblastoma cells (SK-N-MC) by redox activation, which leads to immunoneuropathogenesis. The GSH/GSSG ratio and mRNA expression levels and protein modification of glutathione synthetase (GSS), glutathione perox-idase 1 (GPx1), superoxide dismutase 1 (SOD1), and catalase (CAT) were analyzed in IDCs infected with HIV-1 clade B or clade C as well as in cells treated with the respective Tat proteins. The results indicated that HIV-1 clade B virus and its Tat protein significantly increased the production of reactive oxygen species and reduced the GSH/GSSG ratio and subsequent downregulation of gene expression and protein modification of GSS, GPx1, SOD1, and CAT compared to infection with the clade C virus or treatment with the clade C Tat protein. Thus, our studies demonstrate that HIV-1 clades B and C exert differential effects of redox expression and thiol modification. HIV-1 clade B potentially induces oxidative stress, leading to more immunoneuropathogenesis than infection with HIV-1 clade C.
HIV subtypes or clades differentially induce HIV-associated neurocognitive disorders (HAND) and s... more HIV subtypes or clades differentially induce HIV-associated neurocognitive disorders (HAND) and substance abuse is known to accelerate HIV disease progression. The HIV-1 envelope protein gp120 plays a major role in binding and budding in the central nervous system (CNS) and impacts dopaminergic functions. However, the mechanisms utilized by HIV-1 clades to exert differential effects and the methamphetamine (METH)-associated dopaminergic dysfunction are poorly understood. We hypothesized that clade B and C gp120 structural sequences, modeling based analysis, dopaminergic effect, and METH potentiate neuronal toxicity in astrocytes. We evaluated the effect of clade B and C gp120 and/or METH on the DRD-2, DAT, CaMKs and CREBP transcription. Both the structural sequence and modeling studies demonstrated that clade B gp120 in V1-V4, α-2 and N-glycosylated sites are distinct from clade C gp120. The distinct structure and sequence variation of clade B gp120 differentially impact DRD-2, DAT, CaMK II and CaMK IV mRNA, protein and intracellular expression compared to clade C gp120. However, CREB transcription is upregulated by both clade B and C gp120, and METH co-treatment potentiated these effects. In conclusion, distinct structural sequences of HIV-1 clade B and C gp120 differentially regulate the dopaminergic pathway and METH potentiates neurotoxicity. HIV-1 infection causes immune dysfunction and is a risk factor in the neuropathogenesis of brain disease 1. HIV-infected brain cells secrete inflammatory cytokines, chemokines and neurotoxic factors that alter amino acid metabolism and neurotransmitter systems, including dopamine, acetylcholine and ser-otonin. However, HIV infection has a significant effect on dopamine 2–5. Clinical observations suggest that patients with HIV-associated neurocognitive disorders (HAND) may have dopamine deficits associated with cognitive dysfunctions 6,7. HIV infection alters intracellular Ca 2+ , affecting dopamine levels, dopamine receptors (DRD) and the dopamine transporter (DAT) 8,9. In addition, calcium influx exerts its effects on the ubiquitous Ca 2+ sensor, including the calcium/ calmodulin-dependent protein kinases CaMK II and CaMK IV 10,11 , which affect the cyclic response element binding protein (CREBP) 12,13. Collectively, dopaminergic systems may be vulnerable to the effects of HIV infection in the brain.
HIV infection and illicit drugs are known to induce oxidative stress and linked with severity of ... more HIV infection and illicit drugs are known to induce oxidative stress and linked with severity of viral replication, disease progression, impaired cell cycle regulation and neurodegeneration. Studies have shown that morphine accelerates HIV infection and disease progression mediated by Reactive oxygen species (ROS). Oxidative stress impact redox balance and ROS production affect cell cycle regulation. However, the role of morphine in HIV associated acceleration of oxidative stress and its link to cell cycle regulation and neurodegeneration has not been elucidated. The aim of present study is to elucidate the mechanism of oxidative stress induced glutathione synthases (GSS), super oxide dismutase (SOD), and glutathione peroxidase (GPx) impact cell cycle regulated protein cyclin-dependent kinase 1, cell division cycle 2 (CDK-1/CDC-2), cyclin B, and cell division cycle 25C (CDC-25C) influencing neuronal dysfunction by morphine co-morbidity with HIV-1 gp120. It was observed that redox imbalance inhibited the GSS, GPx and increased SOD which, subsequently inhibited CDK-1/CDC-2 whereas cyclin B and CDC-25C significantly up regulated in HIV-1 gp120 with morphine compared to either HIV-1 gp120 or morphine treated alone in human microglial cell line. These results suggest that HIV positive morphine users have increased levels of oxidative stress and effect of cell cycle machinery, which may cause the HIV infection and disease progression.
Leishmania are obligate intracellular protozoan parasites of mammalian hosts. Promastigotes of Le... more Leishmania are obligate intracellular protozoan parasites of mammalian hosts. Promastigotes of Leishmania are internalized by macrophages and transformed into amastigotes in phagosomes, and replicate in phagolysosomes. Phagosomal maturation arrest is known to play a crucial role in the survival of pathogenic Leishmania within activated macrophages. Recently, tryptophan–aspartate containing coat (TACO) gene has been recognized as playing a central role in the survival of Mycobacterium tuberculosis within human macrophages by arresting the phagosome maturation process. We postulated that a similar association of TACO gene with phagosomes would prevent the vacuole from maturation in the case of Leishmania. In this study we attempted to define the effect of TACO gene downregulation on the entry/survival of Leishmania donovani intracellularly, by treatment with Vitamin D 3 (Vit.D 3)/Retinoic acid (RA) and chenodeoxycholic acid (CDCA)/RA combinations in human THP-1 macrophages (in vitro). Treatment with these molecules downregulated the TACO gene in macrophages, resulting in reduced parasite load and marked reduction of disease progression in L. donovani infected macrophages. Taken together, these results suggest that TACO gene downregulation may play a role in subverting macrophage machinery in establishing the L. donovani replicative niche inside the host. Our study is the first to highlight the important role of the TACO gene in Leishmania entry, survival and to identify TACO gene downregulation as potential drug target against leishmaniasis.
The nanotechnology capable of high-specificity targeted delivery of anti-neoplastic drugs would b... more The nanotechnology capable of high-specificity targeted delivery of anti-neoplastic drugs would be a significant breakthrough in Cancer in general and Ovarian Cancer in particular. We addressed this challenge through a new physical concept that exploited (i) the difference in the membrane electric properties between the tumor and healthy cells and (ii) the capability of magneto-electric nanoparticles (MENs) to serve as nanosized converters of remote magnetic field energy into the MENs' intrinsic electric field energy. This capability allows to remotely control the membrane electric fields and consequently trigger high-specificity drug uptake through creation of localized nano-electroporation sites. In in-vitro studies on human ovarian carcinoma cell (SKOV-3) and healthy cell (HOMEC) lines, we applied a 30-Oe d.c. field to trigger high-specificity uptake of paclitaxel loaded on 30-nm CoFe 2 O 4 @BaTiO 3 MENs. The drug penetrated through the membrane and completely eradicated the tumor within 24 hours without affecting the normal cells. T he development of a technology that is capable of high-specificity targeted delivery of anti-neoplastic drugs would be a significant breakthrough in cancer in general and ovarian cancer in particular. Although the circulatory system can deliver a drug to every cell in the body, delivering the drug specifically inside the tumor cell past its membrane without affecting the healthy cells remains a challenge 1–3. In ovarian cancer, intraperitoneal (IP) delivery through a surgically implanted catheter has shown improved survival rates. However, catheter complications and toxicity have precluded widespread adoption of this invasive means of delivery 4. Current research attempts to go around these limiting factors by using nanoscale systems 5–7. Often, as immunological reagents, monoclonal antibodies are used to recognize the tumor-specific biomarker while the nanoscale control further improves the specificity and targeted drug delivery capability in general 8–10. Nonetheless, in spite of the tremendous progress in this field during the last decades, the capability of targeted delivery with adequately high specificity (to tumor cells) remains an important roadblock to finding a cure for cancer. In this paper, we present a study in which we address this challenge through a new physical concept. It exploits (i) the difference in the electric properties of the membrane between the tumor and healthy cells and (ii) the ability of the recently discovered body-temperature magneto-electric nanoparticles (MENs) to function as nano-converters of remotely supplied magnetic field energy into the MENs' intrinsic electric field energy 11–13. Like the conventional magnetic nanoparticles (MNs), MENs have a non-zero magnetic moment and therefore can be controlled remotely via application of an external magnetic field. However, unlike MNs, MENs offer a new far-reaching function, which is an energy-efficient control of the intrinsic electric fields within the nanoparticles by an external magnetic field. This unprecedented capability is a result of the strong magneto-electric (ME) coupling in this new class of nanostructures even at body temperature 11–13. As a result, MENs introduced in a biological microenvironment act as localized magnetic-to-electric-field nano-converters that allow remote control and generation of the electric signals that underlie the intrinsic molecular interactions. Recently, we exploited this
Based on the type of cells or tissues they tend to harbor or attack, many of the viruses are char... more Based on the type of cells or tissues they tend to harbor or attack, many of the viruses are characterized. But, in case of neurotropic viruses, it is not possible to classify them based on their tropism because many of them are not primarily neurotropic. While rabies and poliovirus are considered as strictly neurotropic, other neurotropic viruses involve nervous tissue only secondarily. Since the AIDS pandemic, the interest in neurotropic viral infections has become essential for all clinical neurologists. Although these neurotropic viruses are able to be harbored in or infect the nervous system, not all the neurotropic viruses have been reported to cause disrupted synaptic plasticity and impaired cognitive functions. In this review, we have discussed the neurotropic viruses, which play a major role in altered synaptic plasticity and neurological disorders.
As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) per... more As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) persists to rise, effective drug treatments are required to treat the infected people. Even though combination antiretroviral therapy (cART) provides stable viral suppression, it is not devoid of undesirable side effects, especially in persons undergoing long-term treatment. The present therapy finds its limitations in the emergence of multidrug resistance and accordingly finding new drugs and novel targets is the need of the hour to treat the infected persons and further to attack HIV reservoirs in the body like brain, lymph nodes to achieve the ultimate goal of complete eradication of HIV and AIDS. Natural products such as plant-originated compounds and plant extracts have enormous potential to become drug leads with anti-HIV and neuroprotective activity. Accordingly, many research groups are exploring the biodiversity of the plant kingdom to find new and better anti-HIV drugs with novel mechanisms of action and for HIV-associated neurocognitive disorders (HAND). The basic challenge that still persists is to develop viral replication-targeted therapy using novel anti-HIV compounds with new mode of action, accepted toxicity and less resistance profile. Against this backdrop, the World Health Organization (WHO) suggested the need to evaluate ethno-medicines for the management of HIV/AIDS. Consequently, there is need to evaluate traditional medicine, particularly medicinal plants and other natural products that may yield effective and affordable therapeutic agents. Although there are a good number of reports on traditional uses of plants to treat various diseases, knowledge of herbal remedies used to manage HIV/AIDS and HAND are scanty, vague and not well documented. In this review, plant substances showing a promising action that is anti-HIV and HAND will be explored along with what they interact. Since some plant substances are also known to modulate several cellular factors which are also involved in the replication of HIV and hence their role as potential candidates will be discussed. HIV/AIDS being an exceptional epidemic, demands an exceptional approach and that forms very much focus for the current review.
During human immunodeficiency virus (HIV) infection, alcohol has been known to induce inflammatio... more During human immunodeficiency virus (HIV) infection, alcohol has been known to induce inflammation while cannabinoids have been shown to have an anti-inflammatory role. For instance cannabinoids have been shown to reduce susceptibility to HIV-1 infection and attenuate HIV replication in macrophages. Recently, we demonstrated that alcohol induces cannabinoid receptors and regulates cytokine production by monocyte-derived dendritic cells (MDDC). However, the ability of alcohol and cannabinoids to alter MDDC function during HIV infection has not been clearly elucidated yet. In order to study the potential impact of alcohol and cannabinoids on differentiated MDDC infected with HIV, monocytes were cultured for 7 days with GM-CSF and IL-4, differentiated MDDC were infected with HIV-1Ba-L and treated with EtOH (0.1 and 0.2%), THC (5 and 10 μM), or JWH-015 (5 and 10 μM) for 4–7 days. HIV infection of MDDC was confirmed by p24 and Long Terminal Repeats (LTR) estimation. MDDC endocytosis assay and cytokine array profiles were measured to investigate the effects of HIV and substances of abuse on MDDC function. Our results show the HIV + EtOH treated MDDC had the highest levels of p24 production and expression when compared with the HIV positive controls and the cannabinoid treated cells. Although both cannabinoids, THC and JWH-015 had lower levels of p24 production and expression, the HIV + JWH-015 treated MDDC had the lowest levels of p24 when compared to the HIV + THC treated cells. In addition, MDDC endocytic function and cytokine production were also differentially altered after alcohol and cannabinoid treatments. Our results show a differential effect of alcohol and cannabinoids, which may provide insights into the divergent inflammatory role of alcohol and cannabinoids to modulate MDDC function in the context of HIV infection.
Methicillin Resistant Staphylococcus aureus (MRSA) has emerged as a major hospital pathogen. Howe... more Methicillin Resistant Staphylococcus aureus (MRSA) has emerged as a major hospital pathogen. However studies from India between 1994-2001, reported the incidence of MRSA between 32.8%-51.6%. In recent years, there have been several reports of community-associated MRSA (CA-MRSA) infections throughout the world. The present study was aimed at the epidemiological survey of methicillin resistant S. aureus in the community and hospital. Samples were collected from hospital (202 samples from staff and patients, 50 samples from operation theatres and ICU) and environmental groups (Swabs from nose and axilla were collected from 70 children and 56 adults). The samples were tested for the presence MRSA. Staphylococci was isolated from 55 (30 from children and 25 from adults) samples from community group where as in 37 samples collected from the various groups of people in the hospital and none from the environment i.e. operation theater and ICU. The S. aureus isolates were studied for methicillin resistance by testing the sensitivity of the isolate to Oxacillin. Of the 26 isolates tested of S. aureus from the community (11 from children and 15 from adults), no MRSA was found. In the hospital, out of the 15 S. aureus isolates, five (33.3%) were confirmed as MRSA. Thus this study shows a prevalence of 33.3% of MRSA in hospital specimens collected from patients, and no carrier state among hospital staff or in the environments. The specimen collected from the community did not show any MRSA. It is possible that CA-MRSA has not yet established in the community studied in the present work at the present time. Further surveillance studies are necessary to continuously monitor the presence of CA-MRSA to alert the clinicians to prevent the serious complications.
The blood-brain barrier (BBB) is considered as the primary impediment barrier for most drugs. Del... more The blood-brain barrier (BBB) is considered as the primary impediment barrier for most drugs. Delivering therapeutic agents to the brain is still a big challenge to date. In our study, a dual mechanism, receptor mediation combined with external non-invasive magnetic force, was incorporated into ferrous magnet-based liposomes for BBB transmigration enhancement. The homogenous magnetic nanoparticles (MNPs), with a size of ∼10 nm, were synthesized and confirmed by TEM and XRD respectively. The classical magnetism assay showed the presence of the characteristic superparamagnetic property. These MNPs encapsulated in PEGylated fluorescent liposomes as magneto-liposomes (MLs) showed mono-dispersion, ∼130 ± 10 nm diameter, by dynamic laser scattering (DLS) using the lipid-extrusion technique. Remarkably, a magnetite encapsulation efficiency of nearly 60% was achieved. Moreover, the luminescence and hydrodynamic size of the MLs was stable for over two months at 4 • C. Additionally, the integrity of the ML structure remained unaffected through 120 rounds of circulation mimicking human blood fluid. After biocompatibility confirmation by cytotoxicity evaluation, these fluorescent MLs were further embedded with transferrin and applied to an in vitro BBB transmigration study in the presence or absence of external magnetic force. Comparing with magnetic force-or transferrin receptor-mediated transportation alone, their synergy resulted in 50-100% increased transmigration without affecting the BBB integrity. Consequently, confocal microscopy and iron concentration in BBB-composed cells further confirmed the higher cellular uptake of ML particles due to the synergic effect. Thus, our multifunctional liposomal magnetic nanocarriers possess great potential in particle transmigration across the BBB and may have a bright future in drug delivery to the brain.
Serum and urine samples were collected from 33 NCC patients before the albendazole treatment, 3–6... more Serum and urine samples were collected from 33 NCC patients before the albendazole treatment, 3–6 and 12 months PT. At 3 months PT, 24 (72.7%) patients had no detectable CT/MRI lesions and 9 (27.2%) patients had persistent lesions. Antibody response to crude soluble extract (CSE), excretory secretory (ES), and lower molecular mass (LMM) (10–30 KDa) antigenic fraction of T. solium cysticerci was detected in serum and urine samples by ELISA. Before the treatment, out of 33 NCC children, 14 (42.4%), 22 (66.6%), and 11 (33.3%) serum samples were found positive with the use of CSE, ES, and LMM antigen, respectively. At 3–6 months PT, positivity rate was 5 (15.1%), 2 (6%), and 4 (12.1%) and at 12 months PT, positivity rate was 5 (15.1%), 0, and 3 (9%) with the use of CSE, ES, and LMM antigen, respectively. There was no significant difference in the positivity with the use of three antigens in pretreatment and PT urine samples. The study suggests that the use of ES antigen to detect antibody in serum samples may serve better purpose to evaluate the therapeutic response in patients with NCC.
To understand HIV pathogenesis or development is no simple undertaking and neither is the cell cy... more To understand HIV pathogenesis or development is no simple undertaking and neither is the cell cycle which is highly complex that requires the coordination of multiple events and machinery. It is interesting that these two processes are interrelated, intersect and interact as HIV-1 infection results in cell cycle arrest at the G2 phase which is accompanied by massive CD4 + T cell death. For its own benefit, in an impressive manner and with the overabundance of tactics, HIV maneuvers DNA damage responses and cell cycle check points for viral replication at different stages from infection, to latency and to patho-genesis. Although the cell cycle is the most critical aspect involved in both viral and cellular replication, in this review, our main focus is on recent developments, including our own observations in the field of cell cycle proteins , checkpoints and strategies utilized by the viruses to manipulate these pathways to promote their own rep-lication and survival. We will also discuss the emerging concept of targeting the replication initiation machinery for HIV therapy.
The blood-brain barrier (BBB) is a diffusion barrier that has an important role in maintaining a ... more The blood-brain barrier (BBB) is a diffusion barrier that has an important role in maintaining a precisely regulated microenvironment protecting the neural tissue from infectious agents and toxins in the circulating system. Compromised BBB integrity plays a major role in the pathogenesis of retroviral associated neurological diseases. Human Immunodeficiency Virus (HIV) infection in the Central Nervous System (CNS) is an early event even before the serodiagnosis for HIV positivity or the initiation of antiretroviral therapy (ART), resulting in neurological complications in many of the infected patients. Macrophages, microglia and astrocytes (in low levels) are the most productively/latently infected cell types within the CNS. In this brief review, we have discussed about the effect of HIV infection and viral proteins on the integrity and function of BBB, which may contribute to the progression of HIV associated neurocognitive disorders.
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Papers by Venkata Atluri