Papers by Johan Groeneveld
Marine Ecology Progress Series, 2002
Long-term movement patterns of deep-water rock lobster Palinurus gilchristi were investigated off... more Long-term movement patterns of deep-water rock lobster Palinurus gilchristi were investigated off the south coast of South Africa using tag recapture data. Over a 12 yr period (1988 to 1999), 30 043 lobsters were tagged at 5 sites. From west to east, these were Cape Agulhas, West and East Agulhas Bank, Mossel Bay to Port Elizabeth, and Port Alfred. The overall recapture rate was 7.51%, with individuals remaining at large for up to 10.3 yr. Overall, 547 (25.8%) tagged lobsters of both sexes moved > 20 km within or between sites. We hypothesized that counter-current migration of juveniles would occur to redress downstream dispersal of phyllosoma larvae by the westerly flowing Agulhas Current. The vast majority of migrants (72.6%) did prove to be immature (carapace length < 72 mm) and did migrate eastwards against the prevailing flow of the Agulhas Current. The Cape Agulhas population (at the western extreme) comprised juveniles only. Over 97% migrated > 50 km, either southeastwards offshore to the West and East Agulhas Bank sites (106 lobsters, covering a mean distance of 154 km), or eastwards alongshore to the Mossel Bay to Port Elizabeth site near the center of the range (33 lobsters, 461 km). The fastest 5% of migrants moved at 0.43 to 0.78 km d-1. In general, Cape Agulhas migrants reached West Agulhas Bank within 1 yr, East Agulhas Bank within 2, and Mossel Bay to Port Elizabeth within 3 yr. The West Agulhas Bank population comprised mostly juveniles and small mature individuals, and 38% migrated, all moving eastwards, either to East Agulhas Bank (66 lobsters, 46 km), or to Mossel Bay to Port Elizabeth (73 lobsters, 426 km). The easterly migration of P. gilchristi was evident but diminished at East Agulhas Bank, virtually absent at Mossel Bay to Port Elizabeth and non-existent at Port Alfred (at the eastern extreme). There was no evidence suggesting a westwards or return migration at any of the 5 sites. It is concluded that Cape Agulhas is an important settlement area for post-larvae originating between Port Elizabeth and West Agulhas Bank, and that juveniles migrate eastwards to redress the downstream displacement. The Port Alfred population is non-migratory and receives no immigrants from elsewhere, adding to other evidence that it is a separate stock, and it is inferred that phyllosoma larvae from this area use a different larval dispersal and return mechanism.
Marine and Freshwater Research, 2014
Penaeid prawns in Ungwana Bay, Kenya, are heavily exploited by artisanal fishers and industrial b... more Penaeid prawns in Ungwana Bay, Kenya, are heavily exploited by artisanal fishers and industrial bottom trawlers. Human activities in mangrove and estuarine areas may affect prawn nursery habitats and influence juvenile recruitment to fished areas, therefore it was important to investigate recruitment patterns in the bay. To test the hypotheses that single genetic stocks exist, we utilised a combination of mtDNA sequence and microsatellite data. Three dominant sympatric species, Penaeus monodon, Fenneropenaeus indicus and Metapenaeus monoceros were targeted. Sample sites were chosen to represent the bulk of fishery activities, and included estuarine juveniles and offshore adults. An exceptionally high mtDNA haplotype diversity, coupled with low nucleotide diversity was observed for all three species and there was no genetic differentiation among sampling sites. Genetic panmixia was confirmed by the microsatellite analyses of P. monodon. Juveniles that recruit to adult populations in Ungwana Bay most likely originate from local estuaries, and conservation of the prawn nursery habitats along the edges of the bay is advocated. Each of the three species represents a single management unit, and the identification of spatial management strategies to mitigate resource-user conflicts should rather consider other ecological and socio-economic factors than the genetic delineation of stocks.
Intensive Care Medicine, Feb 1, 2006
Intensive Care Medicine, 2007
Encyclopedia of Stress, 2007
ICES Journal of Marine Science: Journal du Conseil, 2015
concise review of lobster utilization by worldwide human populations from prehistory to the moder... more concise review of lobster utilization by worldwide human populations from prehistory to the modern era.
Kidney international, 2014
Although 0.9% NaCl solution is by far the most-used fluid for fluid therapy in resuscitation, it ... more Although 0.9% NaCl solution is by far the most-used fluid for fluid therapy in resuscitation, it is difficult to find a paper advocating its use over other types of crystalloid solutions. Literature on the deleterious effects of 0.9% NaCl has accumulated over the last decade, but critical appraisal of alternative crystalloid solutions is lacking. As such, the literature seems to suggest that 0.9% NaCl should be avoided at all costs, whereas alternative crystalloid solutions can be used without scrutiny. The basis of this negative evaluation of 0.9% NaCl is almost exclusively its effect on acid-base homeostasis, whereas the potentially deleterious effects present in other types of crystalloids are neglected. We have the challenging task of defending the use of 0.9% NaCl and reviewing its positive attributes, while an accompanying paper will argue against the use of 0.9% NaCl. It is challenging because of the large amount of literature, including our own, showing adverse effects of 0....
Annals of vascular surgery
We present a patient with Wegener's granulomatosis (WG) with involvement of the abdominal aor... more We present a patient with Wegener's granulomatosis (WG) with involvement of the abdominal aorta, testis, peripheral nerve system, and skin. A 51-year-old man presented at our outpatient clinic with lower back pain. He had a history of smoking, hypertension, and an embryonal carcinoma of the left testis, treated 13 years ago with orchidectomy and chemotherapy. One month earlier, he underwent a partial orchidectomy of the right testis due to testicular swelling. Abdominal computed tomography showed a 3.8 cm wide aneurysm of the distal part of the aorta with inflammation. One week later he was admitted to the hospital with numbness of his hands and feet. Physical examination showed signs of peripheral microemboli. Serological laboratory tests revealed elevated antineutrophil cytoplasmic antibody titers with positive reactions against proteinase-3, indicating Wegener's disease. The chest X-ray was normal. Pathological examination of the right testis showed necrotizing vasculitis...
Critical care (London, England), 2000
Tonometry of gastric mucosal partial carbon dioxide tension (PCO2) has been forwarded as a clinic... more Tonometry of gastric mucosal partial carbon dioxide tension (PCO2) has been forwarded as a clinically applicable tool to monitor regional perfusion adequacy during circulatory failure. The technique is still not used widely, partly because of methodological problems. Current measurement principles are reviewed, with help of the report on PCO2 measurements in gastric juice and tonometer in this issue.
Objective To examine the effects of short-term cyclic stretch on apoptosis in alveolar type II ce... more Objective To examine the effects of short-term cyclic stretch on apoptosis in alveolar type II cells (A549). To study in vitro the direct influence of alveolar type II cells on mechanical stretch. Methods A549 were treated with different doses of lipopolysaccharide (LPS), 0 ng/ml, 1 ng/ml, 10 ng/ml, 100 ng/ml, 1000 ng/ml, and then A549 were lengthened 5%, 15%, 30% using a FLEXCELL tension unit 4000, a vacuum-driven device that applies strain to cells, which were cultured in six-well plates coated with collagen-I, and 12 cycles/min for 4 hours. Apoptosis was measured using the flow cytometry method that measures annexin V and propidium iodide (PI) staining. The morphological changes of apoptotic cells were observed by transmission electron microscope. Results Apoptosis could be induced in alveolar type II cells (A549) by mechanical stretch. The percentage of annexin V + PI cells increased after being treated with cyclic stretch for 4 hours by 5%, 15%, 30% in all groups. The morphological features of apoptotic cells demonstrated by transmission electron microscope were as follows: shrinkage of the cell, chromatin condensation and aggregation under the nuclear membrane as a crescent or lump, membrane-encapsulated nuclear fragment or cell organ formed by invagination of the cell membrane, and apoptotic body formation followed by vacuolization. Conclusion Apoptosis induced by mechanical stretch and LPS is dose dependent. Mechanical stretch aggravates apoptosis especially in cells treated with LPS. Annexin V and PI double staining is a specific, sensitive, and quantitative method for analyzing apoptotic cells. It is also helpful to clarify the protective mechanism of low-volume ventilation in ARDS. PaO 2 /FiO 2 430 [421; 440] # 380 [349; 397] 165 [68; 289] # C (ml/cmH 2 O) 28 [24; 32]* 18 [16; 21]* 12 [8; 17]* R i (cmH 2 O/l/s) 4.1 [3.9; 4.5] 4.5 [4.3; 5.1] 5.1 [3.7; 7.9] # P < 0.05 control vs 24-hour peritonitis, *P < 0.05 control vs 12-hour and 24-hour peritonitis.
Neurocritical Care, 2015
The course and prognostic value of pituitary-thyroid axis hormones is not well studied after card... more The course and prognostic value of pituitary-thyroid axis hormones is not well studied after cardiac arrest. We aimed to study the prognostic role of the pituitary-thyroid axis response to resuscitation from cardiac arrest before, during and after therapeutic hypothermia. We conducted a retrospective cohort study in consecutive comatose patients after out-of-hospital cardiac arrest who were sampled before, during and up to 48 h after a 24-h period of therapeutic hypothermia in the intensive care unit (ICU). Thyroid-stimulating hormone, total and free thyroxine (T4) and triiodothyronine (T3) were determined and compared between ICU outcome groups. We included twenty-nine patients. TSH levels were comparable in non-survivors (n = 17) and survivors (n = 12). The free T4 levels were higher in non-survivors than in survivors (P = 0.001), whereas the free T3 levels were comparable. All samples&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; results similarly declined in both outcome groups up to 72 h after start of 24 h hypothermia. ROC curves analyses showed a maximum AUC of 0.83 (P = 0.003) for free T4 at the end of hypothermia with an optimal cut off ≥17.8 pmol/L to obtain 100 % specificity and positive predictive value for non-survival. Non-survival after cardiac arrest, coma, and therapeutic hypothermia following successful resuscitation is associated with a transient increase in free T4, most probably due to inhibition of free T4 to T3 conversion. However, before routine clinical application, external validation of our finding to assess generalizability is warranted.
PLoS ONE, 2014
Rationale: Pulmonary coagulopathy may play a pathogenetic role in acute respiratory distress synd... more Rationale: Pulmonary coagulopathy may play a pathogenetic role in acute respiratory distress syndrome (ARDS), by contributing to alveolocapillary inflammation and increased permeability. Recombinant human activated protein C (rh-APC) may inhibit this process and thereby improve patient outcome.
Critical care (London, England), 2003
Wiener Klinische Wochenschrift, 2004
... Johan Groeneveld ... A meta-analysis of random-ized, controlled trials. Ann Intern Med 135: 1... more ... Johan Groeneveld ... A meta-analysis of random-ized, controlled trials. Ann Intern Med 135: 149–164 5. Alderson P, Bunn F, Lefebvre C, Li WP, Roberst I, Schier-hout G (2002) Human albumin solution for resuscitation and volume expansion in critically ill patients. ...
Transfusion Medicine, 2010
The aim of the study is to evaluate the effects of red blood cell (RBC) transfusions on pulmonary... more The aim of the study is to evaluate the effects of red blood cell (RBC) transfusions on pulmonary parameters in critically ill, non-bleeding patients. Retrospective chart analysis was performed on critically ill patients without overt bleeding in the intensive care unit (ICU) of a university hospital. In 83 patients in a 5-month period, who had received at least 1 RBC unit and stayed at least 24 h in the ICU, 199 transfusions of median 2 RBCs per transfusion (n = 504) were studied. Pulmonary parameters were retrieved during the period between 24 h before the start of transfusion and 24-48 h after transfusion. Outcome was assessed. The P a O 2 /F I O 2 dose-dependently decreased from 250 ± 105 at baseline to 240 ± 102 mmHg at 24 h after RBC transfusion (P = 0·003), irrespective of acute lung injury at baseline and RBC storage time. The lung injury score (LIS) also increased dose-dependently, whereas, at 48 h, oxygenation and LIS largely returned to baseline. For every seven RBCs transfused, the LIS transiently increased by 1 unit. There were no changes in haemodynamics, lung mechanics or chest radiography. The total number of RBCs given in the ICU did not directly contribute to ICU and 1-year mortality prediction. Transfusion of RBCs decreases oxygenation thereby increasing the LIS, dosedependently and transiently, in a heterogeneous population of critically ill, non-bleeding patients, independent of prior cardiorespiratory status and RBC storage time. The effects are subtle, may go unseen and unreported and may represent subclinical transfusion-related acute lung injury. They do not adversely affect outcome, even at 1-year follow-up.
Transfusion, 2012
Correction added after online publication 11-Jul-11: The spelling of Alexander D. Cornet has been... more Correction added after online publication 11-Jul-11: The spelling of Alexander D. Cornet has been modified.] BACKGROUND: There is an association between blood transfusion and pulmonary complications in cardiac surgery. Mediators of increased pulmonary vascular leakage after transfusion are unknown. We hypothesized that factors may include antibodies or bioactive lipids, which have been implicated in transfusionrelated acute lung injury.
Shock, 2012
Cardiovascular dysfunction is common in severe sepsis or septic shock. Although functional altera... more Cardiovascular dysfunction is common in severe sepsis or septic shock. Although functional alterations are often described, the elevated serum levels of cardiac proteins and autopsy findings of myocardial immune cell infiltration, edema, and damaged mitochondria suggest that structural changes to the heart during severe sepsis and septic shock may occur and may contribute to cardiac dysfunction. We explored the available literature on structural (versus functional) cardiac alterations during experimental and human endotoxemia and/or sepsis. Limited data suggest that the structural changes could be prevented, and myocardial function improved by (pre-)treatment with platelet-activating factor, cyclosporin A, glutamine, caffeine, simvastatin, or caspase inhibitors.
Shock, 2001
ABSTRACT Translocation of luminal bacteria and their products through the intestinal mucosa durin... more ABSTRACT Translocation of luminal bacteria and their products through the intestinal mucosa during ischemia-reperfusion (I/R) may modify I/R injury. To test this hypothesis, 16 germ-free pigs were studied prior to and after clamping the superior mesenteric artery (SMA) and 12 pigs served as controls. Nine pigs in the I/R and 5 in the control group received endotoxin intragastrically, 60 min before baseline. Gut absorption of an inert indicator (polyethyleneglycol [PEG] 3350), gut intraluminal PCO2 (tonometry), and systemic and regional hemodynamic variables were measured up to 4 h after baseline. Gut blood flow was stopped during clamping, some reactive hyperemia occurred up to 30 min after declamping in the I/R groups, independently of prior endotoxin administration. Gut intraluminal-arterial PCO2 gradients were elevated in I/R versus control groups during I and for some time during R, prior endotoxin had no effect. However, in controls without and with luminal endotoxin, PEG urinary excretion, as percentage of the dose administered, was 0.12 +/- 0.12 and 0.17 +/- 0.07, respectively, while it measured 1.82 +/- 0.70 in the I/R group and 0.55 +/- 0.37% in the I/R and endotoxin groups, respectively (P&lt; 0.001). The data suggest that gut luminal endotoxin ameliorates I/R injury of the gut wall in germ-free pigs, without altering changes in gut perfusion adequacy and systemic hemodynamics.
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Papers by Johan Groeneveld