Web services, large and small, use in-memory caches like memcached to lower database loads and qu... more Web services, large and small, use in-memory caches like memcached to lower database loads and quickly respond to user requests. These cache clusters are typically provisioned to support peak load, both in terms of request processing capabilities and cache storage size. This kind of worst-case provisioning can be very expensive (e.g., Facebook reportedly uses more than 10,000 servers for its cache cluster) and does not take advantage of the dynamic resource allocation and virtual machine provisioning capabilities found in modern public and private clouds. Further, there can be great diversity in both the workloads running on a cache cluster and the types of nodes that compose the cluster, making manual management difficult. This paper identifies the challenges in designing large-scale self-managing caches. Rather than requiring all cache clients to know the key to server mapping, we propose an automated load balancer that can perform line-rate request redirection in a far more dynamic manner. We describe how stream analytic techniques can be used to efficiently detect key hotspots. A controller then guides the load balancer's key mapping and replication level to prevent overload, and automatically starts additional servers when needed.
The stimulation of glucose uptake into peripheral tissues is an important mechanism for the remov... more The stimulation of glucose uptake into peripheral tissues is an important mechanism for the removal of glucose in blood and for the management of diabetes mellitus (DM). Since recent results have demonstrated the beneficial effects of flavonoids in relation to DM, this study was designed to examine the effects of 7-O-methylaromadendrin (7-O-MA), a flavonoid isolated from Inula viscosa, on glucose uptake into liver and fat tissue, and investigate the molecular mechanisms involved. 7-O-MA at 10 microM significantly stimulated insulin-induced glucose uptake measured by 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG) in both human hepatocellular liver carcinoma (HepG2) cells and differentiated 3T3-L1 adipocytes. Adipocyte-specific fatty acid binding protein (aP2) gene expression was increased by 7-O-MA in adipocytes, and both gene and protein level of peroxisome proliferator-activated receptor gamma2 (PPARgamma2) was also increased. Moreover, 7-O-MA stimulated ...
In this paper, we reported the realization of 2nd-order random lasing in a half-opened fiber cavi... more In this paper, we reported the realization of 2nd-order random lasing in a half-opened fiber cavity, which is formed by a FBG with central wavelength at the 1st-order Raman Stokes wavelength and a single-mode fiber (SMF) performing as a random distributed feedback mirror. Using this proposed method, the threshold of 1st-order (2nd-order) random lasing is reduced to 0.7 (2.0) W, which is nearly 2 times lower than that observed in a completely-opened cavity.
Increasing evidence shows that TGF-β1 is a key mediator in diabetic nephropathy (DN) and induces ... more Increasing evidence shows that TGF-β1 is a key mediator in diabetic nephropathy (DN) and induces renal fibrosis positively by Smad3 but negatively by Smad7. However, treatment of DN by blocking the TGF-β/Smad pathway remains limited. The present study investigated the anti-fibrotic effect of a traditional Chinese medicine, Chaihuang-Yishen granule (CHYS), on DN. Protective role of CHYS in DN was examined in an accelerated type 1 DN induced by streptozotocin in uninephrectomized Wistar rats. CHYS, at a dose of 0.56 g/kg body weight, was administered by a daily gastric gavage for 20 weeks and the therapeutic effect and potential mechanisms of CHYS on diabetic kidney injury were examined. Treatment with CHYS attenuated diabetic kidney injury by significantly inhibiting 24-h proteinuria and progressive renal fibrosis including glomerulosclerotic index, tubulointerstitial fibrosis index, and upregulation of extracellular matrix (collagen I, IV, and fibronectin), despite the same levels o...
Temporary plastic stent insertion has been considered a safe and effective bridge therapy for dif... more Temporary plastic stent insertion has been considered a safe and effective bridge therapy for difficult common bile duct (CBD) stones. Infusing chemicals to directly dissolve stones through the bile duct might also be effective. However, there are no studies on the efficacy of the combination of these 2 approaches. To investigate the efficacy of a novel ethylenediaminetetraacetic acid (EDTA) and sodium cholate-eluting plastic stent on biliary stones. Ex vivo model by using different doses of active ingredient. An ex vivo bile duct model perfused with porcine bile was created. Stents coated with degradable membranes containing various concentrations of EDTA and sodium cholate were placed in the model with CBD stones. The change in the weight of stents and stones was measured every week during perfusion until the coated membranes were completely biodegraded. The time that the stents required to be fully degraded and the efficiency of stone dissolution were positively correlated with t...
Background and study aim: We previously reported on a plastic stent that was coated with ethylene... more Background and study aim: We previously reported on a plastic stent that was coated with ethylenediaminetetraacetic acid (EDTA) and sodium cholate, which dissolved common bile duct (CBD) stones ex vivo. The aim of this study was to investigate the safety and efficacy of such stents on biliary stones in a live porcine model. Methods: Stents without coating or with degradable membranes containing 0 % or 50 % EDTA and sodium cholate were inserted together with human CBD stones into the porcine CBD. Serum laboratory variables, histological examinations of the bile duct, and the weight change in stones were compared during and after stent placement for 6 months. Results: A total of 16 pigs were included (5 no coating, 5 0 % coating, 6 50 % coating). Biliary stones showed decreased weight in all groups; however, stones in the group with 50 % coated stents showed a greater reduction in weight compared with the no coating and the 0 % coating groups (269 ± 66 mg vs. 179 ± 51 mg [P = 0.09]; 2...
Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion and intracellular ligand-g... more Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion and intracellular ligand-gated channel associated with cystic fibrosis, a lethal genetic disorder common among Caucasians. Here we show that CFTR is robustly activated by membrane stretch induced by negative pressures as small as 5 mmHg at the single-channel, cellular and tissue levels. Stretch increased the product of the number of channels present and probability of being open (NPo), and also increased the unitary conductance of CFTR in cell-attached membrane patches. CFTR stretch-mediated activation appears to be an intrinsic property independent of cytosolic factors and kinase signalling. CFTR stretch-mediated activation resulted in chloride transport in Calu-3 human airway epithelial cells and mouse intestinal tissues. Our study has revealed an unexpected function of CFTR in mechanosensing, in addition to its roles as a ligand-gated anion channel and a regulator of other membrane transporters, demonstrating for the first time a mechanosensitive anion channel with a clearly defined molecular identity. Given that CFTR is often found in mechanically dynamic environments, its mechanosensitivity has important physiological implications in epithelial ion transport and cell volume regulation in vivo.
Journal of renal nutrition : the official journal of the Council on Renal Nutrition of the National Kidney Foundation, 2014
Green tea consumption has been associated with many prophylactic health benefits. This study exam... more Green tea consumption has been associated with many prophylactic health benefits. This study examined for the first time associations between tea consumption and renal function in a Chinese population. Cross-sectional baseline data including demographics, and lifestyle and weekly consumption of green, black, and oolong tea were analyzed from 12,428 ambulatory subjects aged 50 to 85 years (67.3% female) that were randomly selected from the membership list of a community social and welfare association in Guangzhou, China. Associations between tea consumption and renal function were assessed using regression analyses to adjust for potential confounding factors. Renal function was assessed using the estimated glomerular filtration rate (eGFR) and in a subcohort of 1,910 participants using a spot urinary albumin-to-creatinine ratio. Six thousand eight hundred and seventy-two participants drank at least 1 type of tea. Oolong tea consumption was negatively associated with eGFR (β-coefficie...
This study examined the efficacy and pharmacological mechanism of pronase-assisted low-dose antib... more This study examined the efficacy and pharmacological mechanism of pronase-assisted low-dose antibiotics for eradication of Helicobacter pylori. Mongolian gerbils infected with H. pylori received 7-day treatment (omeprazole, different concentrations of pronase, amoxicillin, and clarithromycin), and the efficacy was assessed using the eradication rate and the colonization of H. pylori. In Mongolian gerbils orally administered pronase, the thickness of the gastric mucous layer (GML) was examined using immunohistochemical and alcian blue staining, and the concentrations of amoxicillin in gastric tissue and serum were detected using high-performance liquid chromatography (HPLC). The eradication rates were 80.0% (12/15) in the high-pronase quadruple group (HPQG) and 86.7% (13/15) in the high-antibiotic group (HAG) (P = 1.000). The antibiotic dose in the HPQG was only 1/20 that in the HAG. Thirty minutes after oral treatment with pronase, the sticky protein of the GML was hydrolyzed, and t...
Polyaniline nanomaterial (nPANI) is getting popular in many industrial fields due to its conducti... more Polyaniline nanomaterial (nPANI) is getting popular in many industrial fields due to its conductivity and stability. The fate and effect of nPANI in the environment is of paramount importance towards its technological applications. In this work, the cytotoxicity of nPANI, which was prepared by rapid surface polymerization, was studied on rat celiac macrophages. Cell viability of macrophages treated with various concentrations of nPANI and different periods ranging from 24 to 72 hours was tested by a MTT assay. Damages of nPANI to structures of macrophages were evaluated according to the exposure level of cellular reactive oxygen species (ROS) and change of mitochondrial membrane potential (MMP). We observed no significant effects of nPANI on the survival, ROS level and MMP loss of macrophages at concentrations up to 1 µg/ml. However, higher dose of nPANI (10 µg/ml or above) induced cell death, changes of ROS level and MMP. In addition, an increase in the expression level of caspase-...
Neural circuitry and brain activity depend critically on proper function of voltage-gated calcium... more Neural circuitry and brain activity depend critically on proper function of voltage-gated calcium channels (VGCCs), whose activity must be tightly controlled. We show that the main body of the pore-forming α1 subunit of neuronal L-type VGCCs, Cav1.2, is proteolytically cleaved, resulting in Cav1.2 fragment channels that separate but remain on the plasma membrane. This "midchannel" proteolysis is regulated by channel activity, involves the Ca(2+)-dependent protease calpain and the ubiquitin-proteasome system, and causes attenuation and biophysical alterations of VGCC currents. Recombinant Cav1.2 fragment channels mimicking the products of midchannel proteolysis do not form active channels on their own but, when properly paired, produce currents with distinct biophysical properties. Midchannel proteolysis increases dramatically with age and can be attenuated with an L-type VGCC blocker in vivo. Midchannel proteolysis represents a novel form of homeostatic negative-feedback p...
A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps ... more A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps in the Red Sea. Filled with high concentrations of hydrogen sulfide and ammonia, such a brine pool might limit the spread of eukaryotic organisms. Here, we compared the communities of the eukaryotic microbes in a microbial mat, sediments and water samples distributed in 7 sites within and adjacent to the brine pool. Taxonomic classification of the pyrosequenced 18S rRNA amplicon reads showed that fungi highly similar to the species identified along the Arabic coast were almost ubiquitous in the water and sediment samples, supporting their wide distribution in various environments. The microbial mat displayed the highest species diversity and contained grazers and a considerable percentage of unclassified species. Phylogeny-based methods revealed novel lineages representing a majority of the reads from the interface between the sea water and brine pool. Phylogenetic relationships with more reference sequences suggest that the lineages were affiliated with novel Alveolata and Euglenozoa inhabiting the interface where chemosynthetic prokaryotes are highly proliferative due to the strong chemocline and halocline. The brine sediments harbored abundant species highly similar to invertebrate gregarine parasites identified in different oxygen-depleted sediments. Therefore, the present findings support the uniqueness of some microbial eukaryotic groups in this cold seep brine system.
Previous cross-sectional studies showed that short or long sleep duration was associated with mem... more Previous cross-sectional studies showed that short or long sleep duration was associated with memory impairment (MI), but longitudinal studies are scarce. We examined whether sleep duration was associated with memory decline or development of MI. We conducted a prospective analysis based on the Guangzhou Biobank Cohort Study on 13,888 participants aged 50+ years without MI at baseline and with a follow-up for a mean of 4.1 years. Memory decline was assessed using the Delayed 10-Word Recall Test (DWRT), and in a subset (n = 6,020) with the Mini-Mental State Examination (MMSE). Short and long sleep duration was defined as ≤ 5 hours/day and ≥ 9 hours/day, respectively. Data were analyzed both continuously for memory decline and dichotomously for MI (independently defined as DWRT, < 4; MMSE, < 25). After adjusting for multiple potential confounders, both short and long sleep durations were associated with memory decline using DWRT or MMSE score changes (all P < 0.001). Seven percent (n = 980) developed DWRT-defined MI and 4.0% (n = 194) MMSE-defined MI during the follow-up. Only those with a short (≤ 5 h/day) sleep duration had a significantly increased risk of DWRT-defined MI (odds ratio = 1.53 (95% confidence interval; 1.21-1.93); P…
Phosphorus Sulfur and Silicon and The Related Elements, 1996
The synthesis of amphiphilic thiophene 1 and pyrrole 5 were achieved via Wittig and Friedel-Craft... more The synthesis of amphiphilic thiophene 1 and pyrrole 5 were achieved via Wittig and Friedel-Crafts reactions respectively. The ability of 1 and 5, as well as 3-heptadecylthiophene and poly(3-heptadecylthiophene), to form Langmuir-Blodgett films are discussed.
Cognitive decline is a reduction in cognitive ability usually associated with aging, and those wi... more Cognitive decline is a reduction in cognitive ability usually associated with aging, and those with more extreme cognitive decline either have or are at risk of progressing to mild cognitive impairment and dementia including Alzheimer's disease (AD). We hypothesized that genetic variants predisposing to AD should be predictive of cognitive decline in elderly individuals. We selected 1325 subjects with extreme cognitive decline and 1083 well-matched control subjects from the Guangzhou Biobank Cohort Study in which more than 30,000 southern Chinese older people have been recruited and followed up. Thirty single-nucleotide polymorphisms in 29 AD-associated genes were genotyped. No statistically significant allelic associations with cognitive decline were found by individual variant analysis. At the level of genotypic association, we confirmed that the APOE ε4 homozygote significantly accelerated cognitive decline and found that carriers of the ACE rs1800764_C allele were more likely to show cognitive decline than noncarriers, particularly in those without college education. However, these effects do not survive after multiple testing corrections, and together they only explain 1.7% of the phenotypic variance in cognitive score change. This study suggests that AD risk variants and/or genes are not powerful predictors of cognitive decline in our Chinese sample.
To investigate the clinical features of pediatric Xp11.2 translocation renal cell carcinoma (RCC)... more To investigate the clinical features of pediatric Xp11.2 translocation renal cell carcinoma (RCC). A retrospective review of 22 cases over 35 years. Xp11.2 translocation RCCs were identified in 13 boys and 9 girls with a median age of 10.5 years (range: 2.5-16 years). RCC presented with hematuria in 17, abdominal mass in 1, abdominal masses with hematuria in 2, abdominal pain with hematuria in 1, and as an incidental finding in 1 patient. Ten patients were classified stage I, 10 were stage III, and two were stage IV. Of the 10 patients with stage I RCCs, 3 patients with tumor measuring less than 7 cm had nephron-sparing surgery (NSS) and 17 patients underwent simple nephrectomy. A 15-cm tumor was incompletely removed in one patient and another patient with a 25-cm × 18-cm × 15-cm tumor had gross residual. Of the 15 patients followed up between 6 months and 35 years, 13 were still living and 2 had died after surgery. Xp11.2 translocation RCC is the predominant form of pediatric RCC, associated with advanced stage at presentation. Nephrectomy is the usual treatment for RCC but NSS is an option for patients with tumors measuring<7 cm. Patients with N+M0 maintained a favorable prognosis following surgery alone.
The effects of alcohol dehydrogenase (ADH) 2 and aldehyde dehydrogenase (ALDH) 2 genotypes on the... more The effects of alcohol dehydrogenase (ADH) 2 and aldehyde dehydrogenase (ALDH) 2 genotypes on the alcohol-blood pressure association are unclear. We examined the association of ADH2 or ALDH2 genotypes with blood pressure in older Chinese men. Based on the Guangzhou Biobank Cohort Study (GBCS), 4792 men with valid ADH2, ALDH2 genotypes were included, and genotyping of rs1229984 ADH2 and rs671 ALDH2 (AA, AG/GA or GG) was performed using a Sequenom Mass-Array platform. Information on socio-demographics and lifestyle factors, including alcohol use, was obtained from a questionnaire, and blood pressure was measured. Among alcohol drinkers, systolic and diastolic blood pressure (SBP and DBP) and mean arterial pressure (MAP) were highest for men with the GG ADH2 genotype (136.6, 77.9 and 97.5 mm Hg, respectively), followed by those with the (AA/AG ADH2 þ GG ALDH2) genotype (133.4, 77.6 and 96.2 mm Hg, respectively) and then the (AA/AG ADH2 þ AA/AG ALDH2) genotype (SBP ¼ 132.6, DBP ¼ 76.6 and MAP ¼ 95.2 mm Hg) (P for trend ranged 0.025-0.035). After adjustment for potential confounders, as well as frequency or amount of alcohol use, men with the GG ADH2 genotype were more likely to have hypertension (odds ratio (OR) ¼ 1.62, 95% confidence interval 1.15-2.28) as were men with the (AA/AG ADH2 þ AA/AG ALDH2) genotype (OR ¼ 1.40, 95% confidence interval 1.01-1.96) compared with men with the (AA/AG ADH2 þ GG ALDH2) genotype). ADH2 or ALDH2 genotypes were unrelated to hypertension among those who never drink alcohol. ADH2 genotype influences blood pressure and risk of hypertension among male alcohol drinkers, suggesting that the hypertensive effect of alcohol is due to ethanol rather than acetaldehyde.
Along with our recent investigation on the flexible ligand of H(2)ADA (1,3-adamantanediacetic aci... more Along with our recent investigation on the flexible ligand of H(2)ADA (1,3-adamantanediacetic acid), a series of Zn(II) and Cd(II) metal-organic frameworks, namely, [Zn(3)(ADA)(3)(H(2)O)(2)](n)·5nH(2)O (1), [Zn(ADA)(4,4'-bipy)(0.5)](n) (2), [Zn(2)(ADA)(2)(bpa)](n) (3), [Zn(2)(ADA)(2)(bpa)](n) (4), [Zn(2)(ADA)(2)(bpp)](n) (5), [Cd(HADA)(2)((4,4'-bipy)](n) (6), [Cd(3)(ADA)(3)(bpa)(2)(CH(3)OH)(H(2)O)](n) (7), and [Cd(2)(ADA)(2)(bpp)(2)](n)·7nH(2)O (8) have been synthesized and structurally characterized (where 4,4'-bipy = 4,4'-dipyridine, bpa = 1,2-bis(4-pyridyl)ethane and bpp = 1,3-bis(4-pyridyl)propane). Due to various coordination modes and conformations of the flexible dicarboxylate ligand and the different pyridyl-containing coligands, these complexes exhibit structural and dimensional diversity. Complex 1 exhibits a three-dimensional (3D) framework containing one-dimensional (1D) Zn(II)-O-C-O-Zn(II) clusters. Complex 2 exhibits a 2D structure constructed by 1D double chains based on [Zn(2)ADA(2)] units and a 4,4'-bipy pillar. Complexes 3 and 4 possess isomorphic 2D layer structures, resulting from the different coordination modes of carboxylate group of ADA ligands. Complex 5 features a 2D 4(4) layer in which ADA ligands and Zn(II) atoms construct a 1D looped chain and the chains are further connected by bpp ligands. Complex 6 is composed of 1D zig-zag chains that are entangled through hydrogen-bonding interactions to generate a 2D network. Complex 7 is a rare (3,5)-connected network. Complex 8 possesses a 3D microporous framework with lots of water molecules encapsulated in the channels. The structural diversity of the complexes perhaps mainly results from using diverse secondary ligands and different metal centre ions, and means the assistant ligand and metal centre play important roles in the design and synthesis of target metal-organic frameworks. This finding revealed that ADA could be used as an effective bridging ligand to construct MOFs and change coordination modes and conformational geometries in these complexes. The thermogravimetric analyses, X-ray powder diffraction and solid-state luminescent properties of the complexes have also been investigated.
Web services, large and small, use in-memory caches like memcached to lower database loads and qu... more Web services, large and small, use in-memory caches like memcached to lower database loads and quickly respond to user requests. These cache clusters are typically provisioned to support peak load, both in terms of request processing capabilities and cache storage size. This kind of worst-case provisioning can be very expensive (e.g., Facebook reportedly uses more than 10,000 servers for its cache cluster) and does not take advantage of the dynamic resource allocation and virtual machine provisioning capabilities found in modern public and private clouds. Further, there can be great diversity in both the workloads running on a cache cluster and the types of nodes that compose the cluster, making manual management difficult. This paper identifies the challenges in designing large-scale self-managing caches. Rather than requiring all cache clients to know the key to server mapping, we propose an automated load balancer that can perform line-rate request redirection in a far more dynamic manner. We describe how stream analytic techniques can be used to efficiently detect key hotspots. A controller then guides the load balancer's key mapping and replication level to prevent overload, and automatically starts additional servers when needed.
The stimulation of glucose uptake into peripheral tissues is an important mechanism for the remov... more The stimulation of glucose uptake into peripheral tissues is an important mechanism for the removal of glucose in blood and for the management of diabetes mellitus (DM). Since recent results have demonstrated the beneficial effects of flavonoids in relation to DM, this study was designed to examine the effects of 7-O-methylaromadendrin (7-O-MA), a flavonoid isolated from Inula viscosa, on glucose uptake into liver and fat tissue, and investigate the molecular mechanisms involved. 7-O-MA at 10 microM significantly stimulated insulin-induced glucose uptake measured by 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG) in both human hepatocellular liver carcinoma (HepG2) cells and differentiated 3T3-L1 adipocytes. Adipocyte-specific fatty acid binding protein (aP2) gene expression was increased by 7-O-MA in adipocytes, and both gene and protein level of peroxisome proliferator-activated receptor gamma2 (PPARgamma2) was also increased. Moreover, 7-O-MA stimulated ...
In this paper, we reported the realization of 2nd-order random lasing in a half-opened fiber cavi... more In this paper, we reported the realization of 2nd-order random lasing in a half-opened fiber cavity, which is formed by a FBG with central wavelength at the 1st-order Raman Stokes wavelength and a single-mode fiber (SMF) performing as a random distributed feedback mirror. Using this proposed method, the threshold of 1st-order (2nd-order) random lasing is reduced to 0.7 (2.0) W, which is nearly 2 times lower than that observed in a completely-opened cavity.
Increasing evidence shows that TGF-β1 is a key mediator in diabetic nephropathy (DN) and induces ... more Increasing evidence shows that TGF-β1 is a key mediator in diabetic nephropathy (DN) and induces renal fibrosis positively by Smad3 but negatively by Smad7. However, treatment of DN by blocking the TGF-β/Smad pathway remains limited. The present study investigated the anti-fibrotic effect of a traditional Chinese medicine, Chaihuang-Yishen granule (CHYS), on DN. Protective role of CHYS in DN was examined in an accelerated type 1 DN induced by streptozotocin in uninephrectomized Wistar rats. CHYS, at a dose of 0.56 g/kg body weight, was administered by a daily gastric gavage for 20 weeks and the therapeutic effect and potential mechanisms of CHYS on diabetic kidney injury were examined. Treatment with CHYS attenuated diabetic kidney injury by significantly inhibiting 24-h proteinuria and progressive renal fibrosis including glomerulosclerotic index, tubulointerstitial fibrosis index, and upregulation of extracellular matrix (collagen I, IV, and fibronectin), despite the same levels o...
Temporary plastic stent insertion has been considered a safe and effective bridge therapy for dif... more Temporary plastic stent insertion has been considered a safe and effective bridge therapy for difficult common bile duct (CBD) stones. Infusing chemicals to directly dissolve stones through the bile duct might also be effective. However, there are no studies on the efficacy of the combination of these 2 approaches. To investigate the efficacy of a novel ethylenediaminetetraacetic acid (EDTA) and sodium cholate-eluting plastic stent on biliary stones. Ex vivo model by using different doses of active ingredient. An ex vivo bile duct model perfused with porcine bile was created. Stents coated with degradable membranes containing various concentrations of EDTA and sodium cholate were placed in the model with CBD stones. The change in the weight of stents and stones was measured every week during perfusion until the coated membranes were completely biodegraded. The time that the stents required to be fully degraded and the efficiency of stone dissolution were positively correlated with t...
Background and study aim: We previously reported on a plastic stent that was coated with ethylene... more Background and study aim: We previously reported on a plastic stent that was coated with ethylenediaminetetraacetic acid (EDTA) and sodium cholate, which dissolved common bile duct (CBD) stones ex vivo. The aim of this study was to investigate the safety and efficacy of such stents on biliary stones in a live porcine model. Methods: Stents without coating or with degradable membranes containing 0 % or 50 % EDTA and sodium cholate were inserted together with human CBD stones into the porcine CBD. Serum laboratory variables, histological examinations of the bile duct, and the weight change in stones were compared during and after stent placement for 6 months. Results: A total of 16 pigs were included (5 no coating, 5 0 % coating, 6 50 % coating). Biliary stones showed decreased weight in all groups; however, stones in the group with 50 % coated stents showed a greater reduction in weight compared with the no coating and the 0 % coating groups (269 ± 66 mg vs. 179 ± 51 mg [P = 0.09]; 2...
Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion and intracellular ligand-g... more Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion and intracellular ligand-gated channel associated with cystic fibrosis, a lethal genetic disorder common among Caucasians. Here we show that CFTR is robustly activated by membrane stretch induced by negative pressures as small as 5 mmHg at the single-channel, cellular and tissue levels. Stretch increased the product of the number of channels present and probability of being open (NPo), and also increased the unitary conductance of CFTR in cell-attached membrane patches. CFTR stretch-mediated activation appears to be an intrinsic property independent of cytosolic factors and kinase signalling. CFTR stretch-mediated activation resulted in chloride transport in Calu-3 human airway epithelial cells and mouse intestinal tissues. Our study has revealed an unexpected function of CFTR in mechanosensing, in addition to its roles as a ligand-gated anion channel and a regulator of other membrane transporters, demonstrating for the first time a mechanosensitive anion channel with a clearly defined molecular identity. Given that CFTR is often found in mechanically dynamic environments, its mechanosensitivity has important physiological implications in epithelial ion transport and cell volume regulation in vivo.
Journal of renal nutrition : the official journal of the Council on Renal Nutrition of the National Kidney Foundation, 2014
Green tea consumption has been associated with many prophylactic health benefits. This study exam... more Green tea consumption has been associated with many prophylactic health benefits. This study examined for the first time associations between tea consumption and renal function in a Chinese population. Cross-sectional baseline data including demographics, and lifestyle and weekly consumption of green, black, and oolong tea were analyzed from 12,428 ambulatory subjects aged 50 to 85 years (67.3% female) that were randomly selected from the membership list of a community social and welfare association in Guangzhou, China. Associations between tea consumption and renal function were assessed using regression analyses to adjust for potential confounding factors. Renal function was assessed using the estimated glomerular filtration rate (eGFR) and in a subcohort of 1,910 participants using a spot urinary albumin-to-creatinine ratio. Six thousand eight hundred and seventy-two participants drank at least 1 type of tea. Oolong tea consumption was negatively associated with eGFR (β-coefficie...
This study examined the efficacy and pharmacological mechanism of pronase-assisted low-dose antib... more This study examined the efficacy and pharmacological mechanism of pronase-assisted low-dose antibiotics for eradication of Helicobacter pylori. Mongolian gerbils infected with H. pylori received 7-day treatment (omeprazole, different concentrations of pronase, amoxicillin, and clarithromycin), and the efficacy was assessed using the eradication rate and the colonization of H. pylori. In Mongolian gerbils orally administered pronase, the thickness of the gastric mucous layer (GML) was examined using immunohistochemical and alcian blue staining, and the concentrations of amoxicillin in gastric tissue and serum were detected using high-performance liquid chromatography (HPLC). The eradication rates were 80.0% (12/15) in the high-pronase quadruple group (HPQG) and 86.7% (13/15) in the high-antibiotic group (HAG) (P = 1.000). The antibiotic dose in the HPQG was only 1/20 that in the HAG. Thirty minutes after oral treatment with pronase, the sticky protein of the GML was hydrolyzed, and t...
Polyaniline nanomaterial (nPANI) is getting popular in many industrial fields due to its conducti... more Polyaniline nanomaterial (nPANI) is getting popular in many industrial fields due to its conductivity and stability. The fate and effect of nPANI in the environment is of paramount importance towards its technological applications. In this work, the cytotoxicity of nPANI, which was prepared by rapid surface polymerization, was studied on rat celiac macrophages. Cell viability of macrophages treated with various concentrations of nPANI and different periods ranging from 24 to 72 hours was tested by a MTT assay. Damages of nPANI to structures of macrophages were evaluated according to the exposure level of cellular reactive oxygen species (ROS) and change of mitochondrial membrane potential (MMP). We observed no significant effects of nPANI on the survival, ROS level and MMP loss of macrophages at concentrations up to 1 µg/ml. However, higher dose of nPANI (10 µg/ml or above) induced cell death, changes of ROS level and MMP. In addition, an increase in the expression level of caspase-...
Neural circuitry and brain activity depend critically on proper function of voltage-gated calcium... more Neural circuitry and brain activity depend critically on proper function of voltage-gated calcium channels (VGCCs), whose activity must be tightly controlled. We show that the main body of the pore-forming α1 subunit of neuronal L-type VGCCs, Cav1.2, is proteolytically cleaved, resulting in Cav1.2 fragment channels that separate but remain on the plasma membrane. This "midchannel" proteolysis is regulated by channel activity, involves the Ca(2+)-dependent protease calpain and the ubiquitin-proteasome system, and causes attenuation and biophysical alterations of VGCC currents. Recombinant Cav1.2 fragment channels mimicking the products of midchannel proteolysis do not form active channels on their own but, when properly paired, produce currents with distinct biophysical properties. Midchannel proteolysis increases dramatically with age and can be attenuated with an L-type VGCC blocker in vivo. Midchannel proteolysis represents a novel form of homeostatic negative-feedback p...
A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps ... more A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps in the Red Sea. Filled with high concentrations of hydrogen sulfide and ammonia, such a brine pool might limit the spread of eukaryotic organisms. Here, we compared the communities of the eukaryotic microbes in a microbial mat, sediments and water samples distributed in 7 sites within and adjacent to the brine pool. Taxonomic classification of the pyrosequenced 18S rRNA amplicon reads showed that fungi highly similar to the species identified along the Arabic coast were almost ubiquitous in the water and sediment samples, supporting their wide distribution in various environments. The microbial mat displayed the highest species diversity and contained grazers and a considerable percentage of unclassified species. Phylogeny-based methods revealed novel lineages representing a majority of the reads from the interface between the sea water and brine pool. Phylogenetic relationships with more reference sequences suggest that the lineages were affiliated with novel Alveolata and Euglenozoa inhabiting the interface where chemosynthetic prokaryotes are highly proliferative due to the strong chemocline and halocline. The brine sediments harbored abundant species highly similar to invertebrate gregarine parasites identified in different oxygen-depleted sediments. Therefore, the present findings support the uniqueness of some microbial eukaryotic groups in this cold seep brine system.
Previous cross-sectional studies showed that short or long sleep duration was associated with mem... more Previous cross-sectional studies showed that short or long sleep duration was associated with memory impairment (MI), but longitudinal studies are scarce. We examined whether sleep duration was associated with memory decline or development of MI. We conducted a prospective analysis based on the Guangzhou Biobank Cohort Study on 13,888 participants aged 50+ years without MI at baseline and with a follow-up for a mean of 4.1 years. Memory decline was assessed using the Delayed 10-Word Recall Test (DWRT), and in a subset (n = 6,020) with the Mini-Mental State Examination (MMSE). Short and long sleep duration was defined as ≤ 5 hours/day and ≥ 9 hours/day, respectively. Data were analyzed both continuously for memory decline and dichotomously for MI (independently defined as DWRT, < 4; MMSE, < 25). After adjusting for multiple potential confounders, both short and long sleep durations were associated with memory decline using DWRT or MMSE score changes (all P < 0.001). Seven percent (n = 980) developed DWRT-defined MI and 4.0% (n = 194) MMSE-defined MI during the follow-up. Only those with a short (≤ 5 h/day) sleep duration had a significantly increased risk of DWRT-defined MI (odds ratio = 1.53 (95% confidence interval; 1.21-1.93); P…
Phosphorus Sulfur and Silicon and The Related Elements, 1996
The synthesis of amphiphilic thiophene 1 and pyrrole 5 were achieved via Wittig and Friedel-Craft... more The synthesis of amphiphilic thiophene 1 and pyrrole 5 were achieved via Wittig and Friedel-Crafts reactions respectively. The ability of 1 and 5, as well as 3-heptadecylthiophene and poly(3-heptadecylthiophene), to form Langmuir-Blodgett films are discussed.
Cognitive decline is a reduction in cognitive ability usually associated with aging, and those wi... more Cognitive decline is a reduction in cognitive ability usually associated with aging, and those with more extreme cognitive decline either have or are at risk of progressing to mild cognitive impairment and dementia including Alzheimer's disease (AD). We hypothesized that genetic variants predisposing to AD should be predictive of cognitive decline in elderly individuals. We selected 1325 subjects with extreme cognitive decline and 1083 well-matched control subjects from the Guangzhou Biobank Cohort Study in which more than 30,000 southern Chinese older people have been recruited and followed up. Thirty single-nucleotide polymorphisms in 29 AD-associated genes were genotyped. No statistically significant allelic associations with cognitive decline were found by individual variant analysis. At the level of genotypic association, we confirmed that the APOE ε4 homozygote significantly accelerated cognitive decline and found that carriers of the ACE rs1800764_C allele were more likely to show cognitive decline than noncarriers, particularly in those without college education. However, these effects do not survive after multiple testing corrections, and together they only explain 1.7% of the phenotypic variance in cognitive score change. This study suggests that AD risk variants and/or genes are not powerful predictors of cognitive decline in our Chinese sample.
To investigate the clinical features of pediatric Xp11.2 translocation renal cell carcinoma (RCC)... more To investigate the clinical features of pediatric Xp11.2 translocation renal cell carcinoma (RCC). A retrospective review of 22 cases over 35 years. Xp11.2 translocation RCCs were identified in 13 boys and 9 girls with a median age of 10.5 years (range: 2.5-16 years). RCC presented with hematuria in 17, abdominal mass in 1, abdominal masses with hematuria in 2, abdominal pain with hematuria in 1, and as an incidental finding in 1 patient. Ten patients were classified stage I, 10 were stage III, and two were stage IV. Of the 10 patients with stage I RCCs, 3 patients with tumor measuring less than 7 cm had nephron-sparing surgery (NSS) and 17 patients underwent simple nephrectomy. A 15-cm tumor was incompletely removed in one patient and another patient with a 25-cm × 18-cm × 15-cm tumor had gross residual. Of the 15 patients followed up between 6 months and 35 years, 13 were still living and 2 had died after surgery. Xp11.2 translocation RCC is the predominant form of pediatric RCC, associated with advanced stage at presentation. Nephrectomy is the usual treatment for RCC but NSS is an option for patients with tumors measuring<7 cm. Patients with N+M0 maintained a favorable prognosis following surgery alone.
The effects of alcohol dehydrogenase (ADH) 2 and aldehyde dehydrogenase (ALDH) 2 genotypes on the... more The effects of alcohol dehydrogenase (ADH) 2 and aldehyde dehydrogenase (ALDH) 2 genotypes on the alcohol-blood pressure association are unclear. We examined the association of ADH2 or ALDH2 genotypes with blood pressure in older Chinese men. Based on the Guangzhou Biobank Cohort Study (GBCS), 4792 men with valid ADH2, ALDH2 genotypes were included, and genotyping of rs1229984 ADH2 and rs671 ALDH2 (AA, AG/GA or GG) was performed using a Sequenom Mass-Array platform. Information on socio-demographics and lifestyle factors, including alcohol use, was obtained from a questionnaire, and blood pressure was measured. Among alcohol drinkers, systolic and diastolic blood pressure (SBP and DBP) and mean arterial pressure (MAP) were highest for men with the GG ADH2 genotype (136.6, 77.9 and 97.5 mm Hg, respectively), followed by those with the (AA/AG ADH2 þ GG ALDH2) genotype (133.4, 77.6 and 96.2 mm Hg, respectively) and then the (AA/AG ADH2 þ AA/AG ALDH2) genotype (SBP ¼ 132.6, DBP ¼ 76.6 and MAP ¼ 95.2 mm Hg) (P for trend ranged 0.025-0.035). After adjustment for potential confounders, as well as frequency or amount of alcohol use, men with the GG ADH2 genotype were more likely to have hypertension (odds ratio (OR) ¼ 1.62, 95% confidence interval 1.15-2.28) as were men with the (AA/AG ADH2 þ AA/AG ALDH2) genotype (OR ¼ 1.40, 95% confidence interval 1.01-1.96) compared with men with the (AA/AG ADH2 þ GG ALDH2) genotype). ADH2 or ALDH2 genotypes were unrelated to hypertension among those who never drink alcohol. ADH2 genotype influences blood pressure and risk of hypertension among male alcohol drinkers, suggesting that the hypertensive effect of alcohol is due to ethanol rather than acetaldehyde.
Along with our recent investigation on the flexible ligand of H(2)ADA (1,3-adamantanediacetic aci... more Along with our recent investigation on the flexible ligand of H(2)ADA (1,3-adamantanediacetic acid), a series of Zn(II) and Cd(II) metal-organic frameworks, namely, [Zn(3)(ADA)(3)(H(2)O)(2)](n)·5nH(2)O (1), [Zn(ADA)(4,4'-bipy)(0.5)](n) (2), [Zn(2)(ADA)(2)(bpa)](n) (3), [Zn(2)(ADA)(2)(bpa)](n) (4), [Zn(2)(ADA)(2)(bpp)](n) (5), [Cd(HADA)(2)((4,4'-bipy)](n) (6), [Cd(3)(ADA)(3)(bpa)(2)(CH(3)OH)(H(2)O)](n) (7), and [Cd(2)(ADA)(2)(bpp)(2)](n)·7nH(2)O (8) have been synthesized and structurally characterized (where 4,4'-bipy = 4,4'-dipyridine, bpa = 1,2-bis(4-pyridyl)ethane and bpp = 1,3-bis(4-pyridyl)propane). Due to various coordination modes and conformations of the flexible dicarboxylate ligand and the different pyridyl-containing coligands, these complexes exhibit structural and dimensional diversity. Complex 1 exhibits a three-dimensional (3D) framework containing one-dimensional (1D) Zn(II)-O-C-O-Zn(II) clusters. Complex 2 exhibits a 2D structure constructed by 1D double chains based on [Zn(2)ADA(2)] units and a 4,4'-bipy pillar. Complexes 3 and 4 possess isomorphic 2D layer structures, resulting from the different coordination modes of carboxylate group of ADA ligands. Complex 5 features a 2D 4(4) layer in which ADA ligands and Zn(II) atoms construct a 1D looped chain and the chains are further connected by bpp ligands. Complex 6 is composed of 1D zig-zag chains that are entangled through hydrogen-bonding interactions to generate a 2D network. Complex 7 is a rare (3,5)-connected network. Complex 8 possesses a 3D microporous framework with lots of water molecules encapsulated in the channels. The structural diversity of the complexes perhaps mainly results from using diverse secondary ligands and different metal centre ions, and means the assistant ligand and metal centre play important roles in the design and synthesis of target metal-organic frameworks. This finding revealed that ADA could be used as an effective bridging ligand to construct MOFs and change coordination modes and conformational geometries in these complexes. The thermogravimetric analyses, X-ray powder diffraction and solid-state luminescent properties of the complexes have also been investigated.
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Papers by Wei Zhang