Search

Background. Pancreas transplant volumes are limited because of poor utilization of “extended criteria grafts.” Prolonged cold ischemia is a risk factor associated with poor allograft survival. We aimed to establish the feasibility of transplantation using grafts subjected to prolonged cold ischemia and determine whether these grafts could be optimized using normothermic ex vivo perfusion (NEVP) in a porcine model. Methods. The study population consisted of 35 to 40 kg male Yorkshire pigs in an allotransplantation model with a 3-d survival plan for recipients. Control grafts were subjected to cold storage (CS) in a University of Wisconsin solution for 21 to 24 h (n = 6), whereas the test group received an additional 3 h NEVP after CS of 21 h (n = 5). Results. The 3-d survival was 60% in the NEVP arm versus 0% in the control arm (P = 0.008; log rank). Graft parenchyma was 60% to 70% preserved in the NEVP arm at necropsy on gross appearance. In addition, the islet function was well preserved, and both the pancreas (including the islets) and the duodenal morphology were maintained histologically. The intravenous glucose tolerance test on the day of euthanasia was in the normoglycemic range for 80% of cases in the NEVP arm. Conclusions. Optimization of pancreas grafts exposed to extended CS with NEVP seems promising at rescuing and reanimating these grafts for transplantation, resulting in significantly improved survival in a porcine pancreas transplant model.

Objectives: The majority of available scores to assess mortality risk of coronavirus disease 2019 (COVID-19) patients in the emergency department have high risk of bias. Therefore, this cohort aimed to develop and validate a score at hospital admission for predicting in-hospital mortality in COVID-19 patients and to compare this score with other existing ones. Methods: Consecutive patients (≥ 18 years) with confirmed COVID-19 admitted to the participating hospitals were included. Logistic regression analysis was performed to develop a prediction model for in-hospital mortality, based on the 3978 patients admitted between March–July, 2020. The model was validated in the 1054 patients admitted during August–September, as well as in an external cohort of 474 Spanish patients. Results: Median (25–75th percentile) age of the model-derivation cohort was 60 (48–72) years, and in-hospital mortality was 20.3%. The validation cohorts had similar age distribution and in-hospital mortality. Seven significant variables were included in the risk score: age, blood urea nitrogen, number of comorbidities, C-reactive protein, SpO2/FiO2 ratio, platelet count, and heart rate. The model had high discriminatory value (AUROC 0.844, 95% CI 0.829–0.859), which was confirmed in the Brazilian (0.859 [95% CI 0.833–0.885]) and Spanish (0.894 [95% CI 0.870–0.919]) validation cohorts, and displayed better discrimination ability than other existing scores. It is implemented in a freely available online risk calculator (https://abc2sph.com/). Conclusions: An easy-to-use rapid scoring system based on characteristics of COVID-19 patients commonly available at hospital presentation was designed and validated for early stratification of in-hospital mortality risk of patients with COVID-19.

Summary: Background: Recent evidence indicates a potential therapeutic role of fluvoxamine for COVID-19. In the TOGETHER trial for acutely symptomatic patients with COVID-19, we aimed to assess the efficacy of fluvoxamine versus placebo in preventing hospitalisation defined as either retention in a COVID-19 emergency setting or transfer to a tertiary hospital due to COVID-19. Methods: This placebo-controlled, randomised, adaptive platform trial done among high-risk symptomatic Brazilian adults confirmed positive for SARS-CoV-2 included eligible patients from 11 clinical sites in Brazil with a known risk factor for progression to severe disease. Patients were randomly assigned (1:1) to either fluvoxamine (100 mg twice daily for 10 days) or placebo (or other treatment groups not reported here). The trial team, site staff, and patients were masked to treatment allocation. Our primary outcome was a composite endpoint of hospitalisation defined as either retention in a COVID-19 emergency setting or transfer to tertiary hospital due to COVID-19 up to 28 days post-random assignment on the basis of intention to treat. Modified intention to treat explored patients receiving at least 24 h of treatment before a primary outcome event and per-protocol analysis explored patients with a high level adherence (>80%). We used a Bayesian analytic framework to establish the effects along with probability of success of intervention compared with placebo. The trial is registered at ClinicalTrials.gov (NCT04727424) and is ongoing. Findings: The study team screened 9803 potential participants for this trial. The trial was initiated on June 2, 2020, with the current protocol reporting randomisation to fluvoxamine from Jan 20 to Aug 5, 2021, when the trial arms were stopped for superiority. 741 patients were allocated to fluvoxamine and 756 to placebo. The average age of participants was 50 years (range 18–102 years); 58% were female. The proportion of patients observed in a COVID-19 emergency setting for more than 6 h or transferred to a teritary hospital due to COVID-19 was lower for the fluvoxamine group compared with placebo (79 [11%] of 741 vs 119 [16%] of 756); relative risk [RR] 0·68; 95% Bayesian credible interval [95% BCI]: 0·52–0·88), with a probability of superiority of 99·8% surpassing the prespecified superiority threshold of 97·6% (risk difference 5·0%). Of the composite primary outcome events, 87% were hospitalisations. Findings for the primary outcome were similar for the modified intention-to-treat analysis (RR 0·69, 95% BCI 0·53–0·90) and larger in the per-protocol analysis (RR 0·34, 95% BCI, 0·21–0·54). There were 17 deaths in the fluvoxamine group and 25 deaths in the placebo group in the primary intention-to-treat analysis (odds ratio [OR] 0·68, 95% CI: 0·36–1·27). There was one death in the fluvoxamine group and 12 in the placebo group for the per-protocol population (OR 0·09; 95% CI 0·01–0·47). We found no significant differences in number of treatment emergent adverse events among patients in the fluvoxamine and placebo groups. Interpretation: Treatment with fluvoxamine (100 mg twice daily for 10 days) among high-risk outpatients with early diagnosed COVID-19 reduced the need for hospitalisation defined as retention in a COVID-19 emergency setting or transfer to a tertiary hospital. Funding: FastGrants and The Rainwater Charitable Foundation. Translation: For the Portuguese translation of the abstract see Supplementary Materials section.

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare idiopathic inflammatory disease that mainly affects children and young adults. The clinical signs and symptoms are nonspecific, hindering and delaying the proper diagnosis.We report a case of CRMO in a child with chronic pain in the cervical and thoracic spine. Investigations of the pain revealed a diagnosis of osteomyelitis in the biopsy, indicating a course of antibiotic treatment. After a year, there was progressive worsening of the pain, and it soon spread to the left wrist and right ankle. Magnetic resonance imaging of the left wrist and right ankle revealed morphostructural changes. A new biopsy was performed on the wrist and ankle, and osteomyelitis was pinpointed again.In view of the clinical, radiological, and histopathological findings, the patient was diagnosed with CRMO. The following treatment consisted of nonsteroidal anti-inflammatory drugs, methotrexate, and pamidronate.The strength of this case is the fact that there was extensive imaging and more than one biopsy, and the patient was followed. Magnetic resonance imaging was valuable in assessing the extent and activity of a lesion. Keywords: Osteomyelitis, Chronic, Multifocal, CRMO, MRI

Infective celiac artery aneurysm is an extremely rare diagnosis, with few reported cases in the literature. We present the case of a rapidly expanding celiac artery aneurysm involving the ostia, probably infectious, successfully treated in an urgent setting by aneurysm exclusion resorting to the chimney technique. On follow-up, computed tomography angiography revealed complete aneurysm thrombosis and patent celiac artery. Previous reports of endovascular treatment of infective celiac artery aneurysm involved its embolization. This is the first reported case of chimney technique used to exclude a celiac artery aneurysm, with a clinical suspicion of infectious etiology, preserving celiac artery patency. Short-term results are encouraging, but implantation of prosthetic material in an infected environment is a concern. Keywords: Aneurysm, Infected, Celiac artery, Endovascular procedures

An uncommon complication of iodinated contrast administration is the development of bilateral sialadenitis. We report a unique case of hyperacute unilateral parotiditis during diagnostic cerebral angiography of the external carotid artery, which mimicked possible iatrogenic vascular event associated with cerebral endovascular procedures. Discussion includes the differential diagnosis, diagnostic studies, and treatments for this unusual condition.

Category: Clubfoot Introduction/Purpose: The prevalence of untreated congenital clubfoot among children older than walking age is higher in developing countries due to limited resources for early care after birth. The Ponseti method represents an intervention option for older, untreated children. Methods: A metanalysis was conducted of observational studies selected through a systematic review of articles included in electronic databases (Medline, Scopus, Embase, Lilacs, and the Cochrane Library) until June 2017. A pooling analysis of proportions with 95% confidence intervals (CIs) and a publication bias assessment were performed as routine. Estimates of success, recurrence, and complication rates were weighted and pooled using the random effects model. Results: Twelve studies, including 654 feet diagnosed with congenital clubfoot in children older than walking age (older than 1 year old), were included for analysis. The rate of satisfactory outcomes found via a cluster metanalysis of proportions using the random effects model was 89% (95% CI = 0.82–0.94, p < 0.01), relative to the total analysed. The recurrence rate was 18% (95% CI = 0.14–0.24, p = 0.015), and the rate of casting complications was 7% (95% CI = 0.03–0.15, p = 0.19). Conclusion: Application of the Ponseti method in children with untreated idiopathic clubfoot older than walking age leads to satisfactory outcomes, has a low cost, and avoids surgical procedures likely to cause complications. The results obtained exhibited considerable heterogeneity.

Physical touch can help to decrease the effects of stress. The aim of this study was to evaluate the influence of tactile stimulation on the hormonal and behavioral responses of young adult rats submitted to chronic mild unpredictable stress (CMS), considering the role of angiotensin II (Ang II). In Experiment 1, male rats were divided into 4 groups: control, stress, tactile stimulation (TS), and stress + TS. CMS was applied for three weeks. Tactile stimulation was applied for seven weeks, five days a week. After the CMS protocol, depression-like behaviors were evaluated by forced swimming and sucrose consumption tests. Learning and memory were evaluated using the Y-maze test. Fifteen days after the CMS procedure, the animals were euthanized and the levels of stress hormones were determined. The hypothalamus was isolated for determination of the Ang II concentration. In Experiment 2, control and stressed rats, with or without treatment using losartan (angiotensin II type 1 receptor blocker), were evaluated using the same behavioral tests and the hypothalamus Ang II concentration was also determined. CMS increased plasma corticosterone, norepinephrine, and epinephrine concentrations, induced depression-like behaviors, impaired learning and memory, and increased the Ang II concentration in the hypothalamus. Tactile stimulation attenuated these stress-induced effects. Losartan treatment effectively prevented increase of the hypothalamic Ang II concentration and the development of depression-like behavior, and also reduced the impairment of learning and memory in the stressed animals. The results indicated that tactile stimulation seemed to protect adult rats against hormonal and behavioral chronic stress effects, and that Ang II could be involved in the CMS effects., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Diabetes mellitus and its complications have become a major health concern in Western countries. Increased activity of the intrarenal renin-angiotensin system (RAS) contributes to diabetic nephropathy (DN). We previously reported that in mesangial cells, the high glucose concentration (HG) leads to upregulation of angiotensin-converting enzyme (ACE) messenger RNA, suggesting that ACE was modulated by angiotensin II (Ang II) release. However, this relation in the collecting duct has not yet been studied. We, therefore, aimed to evaluate RAS modulation in inner medullary collecting duct cells (IMCD) exposed to HG. The IMCD were divided into normal glucose (5 mM D-glucose, NG), high glucose (30 mM, HG), and mannitol (30 mM, M) groups. The cells were cultured 48 hr in their respective media. The intracellular and extracellular ACE activity was measured using hippuryl-His-Leu as substrate via a fluorimetric assay and expression was analyzed using western blot analysis. ACE activity, intracellular (27%) and extracellular (22%), was significantly lower in the HG group than in NG and M. ACE2 activity and Ang 1-7 levels were higher in the intracellular compartment. Our data suggest that the HG cannot modify ACE synthesis in IMCD cells but can modulate its activity. The decrease in ACE activity may result in decreased levels of Ang II to protect the IMCD against proliferative and inflammatory deleterious effects of this peptide. Conversely, the increase of ACE2 generating high levels of Ang 1-7, a vasodilator peptide, suggesting that this peptide can induce glucose uptake and protect cells against oxidative stress, which can elicit insulin resistance., (© 2019 Wiley Periodicals, Inc.)

Hypertension is a global health problem, and angiotensin I (ANG I)-converting enzyme (ACE) inhibitors are largely used to control this pathology. Recently, it has been shown that ACE can also act as a transducer signal molecule when its inhibitors or substrates bind to it. This new role of ACE could contribute to understanding some of the effects not explained by its catalytic activity only. In this study, we investigated signaling pathway activation in Chinese hamster ovary (CHO) cells stably expressing ACE (CHO-ACE) under different conditions. We also investigated gene modulation after 4 h and 24 h of captopril treatment. Our results demonstrated that CHO-ACE cells when stimulated with ANG I, ramipril, or captopril led to JNK and ERK1/2 phosphorylation. To verify any physiological role at the endogenous level, we made use of primary cultures of mesangial cells from spontaneously hypertensive rats (SHR) and Wistar rats. Our results showed that ERK1/2 activation occurred mainly in primary cultures of mesangial cells from SHR rats upon captopril stimulation, suggesting that this signaling pathway could be differentially regulated during hypertension. Our results also showed that captopril treatment leads to a decrease of cyclooxygenase 2, interleukin-1β, and β-arrestin2 and a significant increase of AP2 gene expression levels. Our findings strengthen the fact that, in addition to the blockage of enzymatic activity, ACE inhibitors also trigger signaling pathway activation, and this may contribute to their beneficial effects in the treatment of hypertension and other pathologies.

This study determined the interaction of radiation parameters of four biomaterials as attenuators to measure the transmitted X-rays spectra, the mass attenuation coefficient and the effective atomic number by spectrometric system comprising the CdTe detector. The biomaterial BioOss ® presented smaller mean energy than the other biomaterials. The μ/ρ and Z eff of the biomaterials showed their dependence on photon energy. The data obtained from analytical methods of x-ray spectra, µ/ρ and Z eff, using biomaterials as attenuators, demonstrated that these materials could be used as substitutes for dentin, enamel and bone. Further, they are determinants for the characterization of the radiation in tissues or equivalent materials., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Envenoming snakebites are thought to be a particularly important threat to public health worldwide, especially in rural areas of tropical and subtropical countries. The true magnitude of the public health threat posed by snakebites is unknown, making it difficult for public health officials to optimize prevention and treatment. The objective of this work was to conduct a systematic review of the literature to gather data on snakebite epidemiology in the Amazon region and describe a case series of snakebites from epidemiological surveillance in the State of Amazonas (1974-2012). Only 11 articles regarding snakebites were found. In the State of Amazonas, information regarding incidents involving snakes is scarce. Historical trends show an increasing number of cases after the second half of the 1980s. Snakebites predominated among adults (20-39 years old; 38%), in the male gender (78.9%) and in those living in rural areas (85.6%). The predominant snake envenomation type was bothropic. The incidence reported by the epidemiological surveillance in the State of Amazonas, reaching up to 200 cases/100,000 inhabitants in some areas, is among the highest annual snakebite incidence rates of any region in the world. The majority of the cases were reported in the rainy season with a case-fatality rate of 0.6%. Snakebite envenomation is a great disease burden in the State of Amazonas, representing a challenge for future investigations, including approaches to estimating incidence under-notification and case-fatality rates as well as the factors related to severity and disabilities.

Local activation of the renin-angiotensin system (RAS) has been implicated in the pathogenesis of several renal disorders. In this study we investigated how chronic kidney disease (CKD) modulates RAS components in an experimental model. Male Wistar rats were divided into three groups: sham, nephrectomized, and nephrectomized receiving losartan. Chronic kidney disease animals presented decreased renal N-domain angiotensin-converting enzyme (ACE) activity but overexpression of N-domain ACE in urine. Remnant kidneys presented high angiotensin II levels. Losartan treatment increased urine and tissue ACE activity and tissue levels of angiotensins, mainly angiotensin (1-7), and improved renal and histopathologic parameters. Taken together, the authors' results indicate that pathophysiological changes due to CKD could lead to an increased expression of somatic and N-domain ACE, mainly the 65 kDa isoform, suggesting that this enzyme could be used as a biological urinary marker in CKD.

Some environmental interventions can result in physiologic and behavioral changes in laboratory animals. In this context, the handling of adolescent or adult rodents has been reported to influence exploratory behavior and emotionality. Here we examined the effects of handling on memory and anxiety levels of adolescent rats. Male Sprague-Dawley rats (age, 60 d) were divided into a control group and a handled group, which were handled for 5 min daily, 5 d per week, for 6 wk. During handling bouts, the rat was removed from its cage, placed in the experimenter's lap or on the top of a table, and had its neck and back gently stroked by the experimenter's fingers. During week 6, each rat's anxiety level was evaluated in the elevated plus-maze (EPM) test. Learning and memory were evaluated 48 h later, by measuring escape latency in the elevated plus-maze test. Plasma corticosterone and catecholamine levels were measured also. Norepinephrine levels were lower in the handled rats compared with control animals, with no differences in epinephrine and corticosterone. As compared with the control rats, the handled rats showed increases in the percentage of time spent in the open arms of the test apparatus, percentage of entries into open arms, and number of visits to the end of the open arms and decreases in the latency of the first open arm entry. Escape latency was lower in the handled rats compared with control rats in both the first and second trials. The data obtained suggest that handling decreases anxiety levels and improves learning skills and memory in rats.

Introduction and Hypothesis: The objective of this study is to evaluate pregnancy's action on glycosaminoglycans (GAGs) profile in bladder and urethra of female adult rats., Methods: Twenty adult female rats were divided into four groups: control, day 10 pregnancy, day 20 pregnancy, and day 5 after delivery. Sulfated GAGs content were determined by densitometry. Hyaluronic acid was assessed by fluorimetric enzyme-linked immunosorbent serologic-like assay. Radioactive GAGs were quantified by measuring radioactivity in electrophoresis gel. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney tests., Results: In all groups, dermatan sulfate was predominant followed by heparan sulfate and hyaluronic acid. Significant decrease in total GAGs in bladder was observed at the beginning of pregnancy, with progressive increase. Biosynthesis of such molecules showed a similar behavior. In urethra, changes in GAGs content were restricted to the end of pregnancy. Hyaluronic acid content showed a significant increase in bladder during puerperium., Conclusions: We observed different composition in vesical and urethral tissues during pregnancy and in puerperium.

Background: To assess the prognostic value of plasmatic fibronectin (FN), compared to numeric Child-Pugh classification and its biochemical parameters in patients with alcoholic cirrhosis followed prospectively during a 18 months-period., Methods: Fifty patients with the diagnosis of cirrhosis by hepatic biopsy or clinical and biochemical criteria, were included in the study after the exclusion of hepatocarcinoma and GI bleeding, infection or continous alcohol ingestion in the last 30 days. The mean age was 51.3+/-12.6 years, being 72% males and 17 of them were classified as Child-Pugh A, 18 as B and 15 as C. Serum bilirubin concentration was measured in autoanalyzer, protein electrophoresis was performed on cellulose acetate and prothrombin time by the Quick test. Plasmatic FN was assessed by radial immunodiffusion with anti-human FN in 1% agarose gel slabs., Results: One patient was excluded because no natural death and 12 died owing to hepatic disease. The numeric Child-Pugh [score > 10, Relative Risk (RR)=11.33] and total bilirubins (> 2.5 mg/dL, RR=9.47) were the best predictors of death. Mean plasmatic FN concentration was significantly higher among those who survived when compared with those who died (185+/-66 mg/L x 131+/-38 mg/L, p<0.01), with a RR=6.59, for FN < 165 mg/L. Higher levels of FN, on the other hand, were the best variable to predict survival, since 96% of these 29 patients were alive at the end of follow-up., Conclusion: Although having less accuracy in predicting the risk of death of these patients, plasmatic FN > 165 mg/L was better predictor of survival than Child-Pugh score or any one of its biochemical parameters.

1. Proteoglycans provide negatively charged sites on the surface of platelets, leukocytes and endothelial cells. Since chondroitin 4-sulphate is the main proteoglycan present on the platelet surface, the role of this molecule in mediating the activation of human platelets by polylysine was studied. 2. Platelets were desensitized with phorbol 12-myristate 13-acetate (PMA, 10 nM) 5 min before the addition of polylysine to platelet-rich plasma (PRP). Changes in the intracellular Ca2+ concentration were measured in fura2-am (2 microM) loaded platelets and protein phosphorylation was assessed by autoradiography of the electrophoretic profile obtained from [32P]-phosphate labelled platelets. The release of dense granule contents was measured in [14C]-5-hydroxytryptamine loaded platelets and the synthesis of thromboxane (TXA2) was assessed by radioimmunoassay. Surface chondroitin 4-sulphate proteoglycan was degraded by incubating platelets with different concentrations of chondroitinase AC (3 min, 37 degrees C). The amount of chondroitin 4-sulphate remaining in the platelets was then quantified after proteolysis and agarose gel electrophoresis. 3. The addition of PMA to PRP before polylysine inhibited the aggregation by 88 +/- 18% (n = 3). Staurosporine (1 microM, 5 min) prevented the PMA-induced inhibition. Chondroitinase AC (4 pu ml-1 to 400 muu ml-1, 3 min) abolished the polylysine-induced aggregation in PRP but caused only a discrete inhibition of ADP-induced aggregation. The concentration of chrondroitin 4-sulphate in PRP (0.96 +/- 0.2 microgram/10(8) platelets, n = 3) and in washed platelets (WP; 0.35 +/- 0.1 microgram/10(8) platelets, n = 3) was significantly reduced following incubation with chondroitinase AC (PRP = 0.63 +/- 0.1 microgram/10(8) platelets and WP = 0.08 +/- 0.06 microgram/10(8) platelets). 4. Washed platelets had a significantly lower concentration of chondroitin 4-sulphate than platelets in PRP. The addition of polylysine to WP induced a rapid increase in light transmission which was not accompanied by TXA2 synthesis or the release of dense granule contents. This effect was not inhibited by sodium nitroprusside (SNP), iloprost, EDTA or the peptide RGDS. This event was accompanied by the discrete phosphorylation of plekstrin and myosin light chain, which were inhibited by staurosporine (10 microM, 10 min). The hydrolysis of platelet surface chondroitin 4-sulphate strongly reduced the polylysine-induced phosphorylation. 5. Our results indicate that polylysine activates platelets through a specific receptor which could be the proteoglycan chondroitin 4-sulphate present on the platelet membrane.

Unlabelled: Patients with alcoholic chronic liver disease when treated with colchicine during a 12 month-period improved significantly the plasmatic levels of albumin and prothrombin when compared with a similar group of patients who took placebo. No differences in the mortality rate and in number of patients admitted at the hospital could be detected among those groups during this period., Purpose: To evaluate the clinical outcome and the plasmatic levels of albumin, pre-albumin, prothrombin and transferrin in patients presenting alcoholic chronic liver disease taking colchicine or placebo, during a 12-month period., Methods: In a double-blind, randomized, controlled trial, 41 patients with alcoholic chronic liver disease were assigned to either placebo (20 patients) or a colchicine (21 patients) treatment group, assessing their clinical course (mortality rate and hospital admission) and plasmatic protein levels during a 12-month period. Albumin, pre-albumin and transferrin plasmatic levels were assessed through a immunodiffusion radial method and prothrombin time and activity was assessed by a one stage Quick modified method., Results: At the end of the trial, only 7.3% of the patients were lost during follow-up. No statistical differences could be found in mortality and number of patients admitted at the hospital among placebo and colchicine groups. Comparatively to the placebo group, a significant increase in the mean of percentage variation was found in patients of the colchicine group for serum albumin levels (17.9% colchicine x 3.6% placebo, p < 0.05) and for prothrombin activity (19.2% colchicine x 2.1% placebo, p < 0.05). A similar pattern of response was found in pre-albumin serum levels, but such differences were not statistically different. No differences were found in serum transferrin levels among both groups., Conclusion: These results suggest that colchicine intake has a positive effect on plasmatic protein levels in patients with alcoholic chronic liver disease.

1. In platelet rich plasma (PRP), chondroitin 4-sulfate release from platelets occurred after stimulation with ADP (5 microM), collagen (5-10 micrograms/ml), or adrenaline (10 microM). Release started within 60 s and maximum release (0.7-2.0 mg/l) was reached within 180 s. TXA2 formation and dense granule release reached a maximum within 90 s after stimulation. 2. Using washed platelets (1.5 x 10(8) cells/ml), the platelet responses were faster. Release of chondroitin 4-sulfate and TXA2 started within 20-30 s after thrombin addition (100 mU/ml). Maximum release was reached within 60 s in both cases. Dense granule release started in the first 5 s of stimulation (34.6 +/- 12.4%) reaching maximum secretion (74.4 +/- 8.7%) within 60 s. 3. Our results demonstrate that maximal chondroitin 4-sulfate release occurs after the dense granule release reaction in both PRP and washed platelets. This observation suggests that chondroitin 4-sulfate is unlikely to be stored in the dense granules but may be stored in the alpha-granules.

We have investigated the effects of nontoxic doses of vitamin A on the hepatic contents of collagen and sulfated glycosaminoglycans (SGAGs) in rats chronically treated with CCl4. When the animals were treated with this retinoid before the intoxication with CCl4, liver collagen level was significantly reduced as compared with that in rats that received only CCl4 (3.31 +/- 0.40 vs 5.00 +/- 0.61 mg/gm wet liver, mean +/- SD, respectively), although no significant differences were found for the relative proportion of type III collagen related to type I collagen. The absolute increment in the total amount of liver SGAG in the vitamin A--pretreated group was followed by a more important increase in the concentration of dermatan sulfate as compared with the CCl4 group (dermatan sulfate-to-heparan sulfate ratio: 1.15 for the CCl4 group vs 1.70 for the vitamin A--pretreated group). A significant proportion of the dermatan sulfate from this last group was of higher molecular weight when compared with the dermatan sulfate found in the liver of rats that received only CCl4. Our results indicate that the pretreatment with vitamin A modifies hepatic collagen and SGAG deposition and can inhibit or delay the development of liver cirrhosis in rats chronically treated with CCl4. We speculate that this effect could be due to the changes in the fat-storing (Ito) cells phenotype induced by vitamin A.