What to expect and when: benznidazole toxicity in chronic Chagas' disease treatment.

Background: Benznidazole is one of the two most effective antiparasitic drugs for Chagas' disease treatment. However, knowledge about its toxicity profile is mostly based on post-marketing observational studies. Objectives: Our study combines data from two prospective clinical trials designed to assess the safety of the drug newly produced by ELEA Laboratories (Abarax®). Methods: Eligible participants were selected using a consecutive sampling strategy in the CINEBENZ and BIOMARCHA studies between 2013 and 2016 (EUDRACT 2011-002900-34 and 2012-002645-38, respectively, and clinicaltrials.gov NCT01755403 and NCT01755377, respectively). Enrolled subjects received treatment with 5 mg/kg/day benznidazole orally in two divided doses for 8 weeks and were followed up fortnightly. Results: We observed 305 adverse reactions in 85 of 99 participants (85.9%). Each patient had a median of three adverse reactions, 89.5% were mild and the median duration was 12 days. Most adverse reactions appeared in the first month of treatment except arthritis and peripheral neuropathy. Twenty-six patients did not complete treatment: 2 were withdrawn, 1 for ectopic pregnancy and 1 for epilepsy relapse due to cysticercosis; 2 were lost to follow-up; and 22 were owing to adverse reactions, two of them severe. We observed some unexpected adverse reactions that have not been described previously, such as psychiatric symptoms, erectile dysfunction, menstrual cycle alterations and lung infiltration. Conclusions: There is a very high frequency of adverse reactions to benznidazole. Most adverse reactions are mild, but the treatment burden is significant and unexpected reactions are not rare. Severe reactions are uncommon, but they can be life-threatening. Further studies are necessary to optimize treatment.

Older type 2 diabetic patients are more likely to achieve glycaemic and cardiovascular risk factors targets than younger patients: analysis of a primary care database.

BACKGROUND: Older subjects with type 2 diabetes mellitus (T2DM) have differential characteristics compared with middle-aged or younger populations, and require tailored management of the disease. AIMS: To evaluate how clinical characteristics, degree of control of glycaemia and cardiovascular risk factors, presence of chronic complications and treatments differ between older T2DM patients and younger adults. METHODS: Cross-sectional study using data from a population-based electronic database. We retrieved data from 318,020 patients ≥ 30 years diagnosed with T2DM, attended during 2011 in primary care centres in Catalonia, Spain. We performed descriptive and comparative analyses stratified by gender and age subgroups: ≤ 65, 66-75, 76-85 and >85 years. RESULTS: Both men and women across older age subgroups (> 65 years) had longer diabetes duration than younger adults (8.0 vs. 5.6 in men and 8.4 vs. 6.9 years in women; p < 0.001), but better glycaemic control (mean glycated haemoglobin 7.1 vs. 7.7 in men and 7.1 vs. 7.4 in women; p < 0.001), and better combined control of different cardiovascular risk factors (p < 0.001). Moreover, older patients were more likely to achieve glycaemic targets irrespective of having cardiovascular disease. The use of oral antidiabetics decreased with increasing age, and insulin in monotherapy was more frequently prescribed among patients in the older age subgroups. Diabetes-related complications were more frequent in men of all group ages. In the older age subgroups, patients of both sexes had a longer duration of T2DM but better glycaemic control. In this context, the prevalence of diabetic retinopathy decreased unexpectedly with increasing age. CONCLUSION: Control of glycaemia and cardiovascular risk factors was better among older T2DM patients. There is a need for prospective studies to quantify the weight of risk factors in each complication to adapt the therapeutic and care approaches in elderly people.

Sex-dependent differences in rat brown adipose tissue mitochondrial biogenesis and insulin signaling parameters in response to an obesogenic diet.

Marked sex-dependent differences in mitochondrial function and redox status have been found in brown adipose tissue (BAT) of control rats. Insulin also plays a role in the development and maintenance of this tissue. The aim was to investigate sexual dimorphism in the effects of diet-induced obesity on BAT mitochondrial function, as well as on insulin signaling pathway. 10-week-old Wistar rats of both sexes were fed a control diet or a palatable high-fat diet for 26 weeks. Serum markers of insulin sensitivity were analyzed. Mitochondrial DNA (mtDNA) content, mitochondrial oxidative activities, PGC-1α mRNA levels, as well as the protein levels of insulin receptor subunit ß (IRß), glucose transporter GLUT4, ß(3)-adrenergic receptor (ß(3)-AR), phosphatidylinositol 3-kinase, mitochondrial transcription factor A (TFAM), cytochrome c oxidase subunit IV (COX IV), and uncoupling protein 1 (UCP1) were measured in BAT. Obese females showed impaired systemic insulin sensitivity accompanied by diminished IRß, GLUT4, and ß(3)-AR protein levels in BAT. In addition, TFAM and COX IV protein and PGC-1α mRNA levels decreased in obese females, whereas mtDNA levels increased. In obese males, oxidative and thermogenic capacities rose and no significant changes were observed in the insulin signaling pathway elements. The reduction of the insulin signaling pathway in BAT of obese females may be responsible, at least partially, for the impaired biogenesis process, which could favor the increase of body weight found in this sex. In contrast, the enhanced mitochondrial functionality in the BAT of males would avoid increased oxidative damage and the impairment of insulin signaling.

Altered glucose-stimulated insulin secretion in a mouse line with activated polyamine catabolism.

Ubiquitous activation of polyamine catabolism has been demonstrated to have protective effects in mice on fat accumulation and insulin sensitivity/glucose tolerance in, both, normal conditions and after a high fat diet. We have analyzed the endocrine pancreas functionality in four months-old male mice overexpressing the rate limiting enzyme in the polyamine catabolism, spermidine/spermine N¹-acetyltransferase (SSAT). The pancreatic SSAT activity was 37-fold elevated in the transgenic mice, which reduced the total pancreatic and islet pools of spermidine (71%) and spermine (69%), and increased putrescine and N¹-acetyl spermidine. Reduction in the islet ATP levels (65%) was accompanied with increased transcription of 5'-AMP-activated protein kinase (AMPK) (1.5-fold) and Foxa2 (2.7-fold), and reduced HNF4α (67%) and HNF1α (92%), insulin 1 (47%), insulin 2 (50%), and Glut2 (57%). Moreover, the SSAT transgenic mice also presented increased beta cell area, decreased insulin production, and altered glucose-stimulated insulin secretion. It has been hypothesized that the acute activation of the polyamine catabolism produces a futile cycle that greatly decreases the energy reserves of the cell. The lower energy status would activate the energy expenditure regulator, AMPK, which would consequently repress the PI3K/Akt pathway, and activate the transcription factor Foxa2.

In vivo genetic engineering of murine pancreatic beta cells mediated by single-stranded adeno-associated viral vectors of serotypes 6, 8 and 9.

AIMS/HYPOTHESIS: The genetic engineering of pancreatic beta cells could be a powerful tool for examining the role of key genes in the cause and treatment of diabetes. Here we performed a comparative study of the ability of single-stranded (ss) adeno-associated viral vectors (AAV) of serotypes 6, 8 and 9 to transduce the pancreas in vivo. METHODS: AAV6, AAV8 and AAV9 vectors encoding marker genes were delivered to the pancreas via intraductal or systemic administration. Transduced cells were analysed by immunostaining. AAV9 vectors encoding hepatocyte growth factor (HGF) were delivered intraductally to a transgenic mouse model of type 1 diabetes and glycaemia was monitored. RESULTS: AAV6, AAV8 and AAV9 mediated efficient and long-term transduction of beta cells, with AAV6 and AAV8 showing the highest efficiency. However, alpha cells were poorly transduced. Acinar cells were transduced by the three serotypes tested and ductal cells only by AAV6. In addition, intraductal delivery resulted in higher AAV-mediated transduction of the pancreas than did systemic administration. As proof of concept, intraductal delivery of AAV9 vectors encoding for the beta cell anti-apoptotic and mitogenic HGF preserved beta cell mass, diminished lymphocytic infiltration of the islets and protected mice from autoimmune diabetes. CONCLUSIONS/INTERPRETATION: Intraductal administration of AAV6, AAV8 and AAV9 is an efficient way to genetically manipulate the pancreas in vivo. This technology may prove useful in the study of islet physiopathology and in assessment of new gene therapy approaches designed to regenerate beta cell mass during diabetes.

Brown adipose tissue redox status in response to dietary-induced obesity-associated oxidative stress in male and female rats.

Obesity is linked to systemic oxidative stress and, although brown adipose tissue (BAT) plays a crucial role in energy balance, BAT redox status effects on obesity have not been studied previously. Female rats exhibit a greater BAT thermogenic capacity, attributed to enhanced mitochondrial differentiation, than males. The aim of this study was to investigate whether the mitochondrial sexual dimorphism is related to differences in BAT redox status and to assess its role in the regulation of body weight gain in response to chronic high fat diet (HFD) feeding. Ten-week-old Wistar rats of both genders were fed a pelleted control diet or HFD for 26 weeks. Although mitochondria of female rats produced higher levels of hydrogen peroxide than those of males, females exhibited lower oxidative damage, attributed to greater glutathione peroxidase activity and higher glutathione content. In response to HFD, body weight increased markedly in females, but oxidative capacity increased only in males, thus maintaining improved BAT redox status compared with females. In conclusion, the sexual dimorphism in BAT redox status found in control animals is attenuated by the HFD. The enhanced oxidative capacity of HFD males can be related to their greater resistance to body weight gain.

IGF-I mediates regeneration of endocrine pancreas by increasing beta cell replication through cell cycle protein modulation in mice.

AIMS/HYPOTHESIS: Recovery from diabetes requires restoration of beta cell mass. Igf1 expression in beta cells of transgenic mice regenerates the endocrine pancreas during type 1 diabetes. However, the IGF-I-mediated mechanism(s) restoring beta cell mass are not fully understood. Here, we examined the contribution of pre-existing beta cell proliferation and transdifferentiation of progenitor cells from bone marrow in IGF-I-induced islet regeneration. METHODS: Streptozotocin (STZ)-treated Igf1-expressing transgenic mice transplanted with green fluorescent protein (GFP)-expressing bone marrow cells were used. Bone marrow cell transdifferentiation and beta cell replication were measured by GFP/insulin and by the antigen identified by monoclonal antibody Ki67/insulin immunostaining of pancreatic sections respectively. Key cell cycle proteins were measured by western blot, quantitative RT-PCR and immunohistochemistry. RESULTS: Despite elevated IGF-I production, recruitment and differentiation of bone marrow cells to beta cells was not increased either in healthy or STZ-treated transgenic mice. In contrast, after STZ treatment, IGF-I overproduction decreased beta cell apoptosis and increased beta cell replication by modulating key cell cycle proteins. Decreased nuclear levels of cyclin-dependent kinase inhibitor 1B (p27) and increased nuclear localisation of cyclin-dependent kinase (CDK)-4 were consistent with increased beta cell proliferation. However, islet expression of cyclin D1 increased only after STZ treatment. In contrast, higher levels of cyclin-dependent kinase inhibitor 1A (p21) were detected in islets from non-STZ-treated transgenic mice. CONCLUSIONS/INTERPRETATION: These findings indicate that IGF-I modulates cell cycle proteins and increases replication of pre-existing beta cells after damage. Therefore, our study suggests that local production of IGF-I may be a safe approach to regenerate endocrine pancreas to reverse diabetes.

Transgenic mice overexpressing alpha2A-adrenoceptors in pancreatic beta-cells show altered regulation of glucose homeostasis.

AIMS/HYPOTHESIS: To study the role of the human alpha2A-adrenoceptor in the regulation of insulin secretion and the maintenance of glucose homeostasis in transgenic mice overexpressing this receptor in pancreatic beta cells. METHODS: A human insulin promoter/human alpha2C10-adrenoceptor chimeric gene was microinjected into mouse embryos and transgenic mice were obtained. RESULTS: Analysis by RT-PCR showed that the expression of the transgene was restricted to pancreatic islets. Study of the binding of the alpha2-antagonist [3H]RX821002 to membrane preparations showed that islets from transgenic mice had ninefold higher alpha2-adrenoceptor density than those from controls. Immunohistological analysis showed, however, no change in the number or size of islets between control and transgenic mice. Transgenic animals had normal glycaemia and insulinaemia in basal conditions but greater hyperglycaemic and hypoinsulinaemic responses after injection of the alpha2-agonist, UK14304. The lower blood insulin concentration detected in transgenic mice was a reflection of a stronger inhibitory effect of the alpha2-agonist on glucose-stimulated insulin secretion in transgenic islets than in controls. Furthermore, transgenic mice did not have lower glycaemia to basal values after an intraperitoneal glucose tolerance test. This defect was abolished by treatment with the alpha2-adrenoceptor antagonist, RX821002. CONCLUSION/INTERPRETATION: These results provide evidence in vivo that overexpression of alpha2-adrenoceptors in beta cells can lead to impaired insulin secretion and glucose intolerance.

Anti-inflammatory action of type I interferons deduced from mice expressing interferon beta.

Type I interferons (IFN) are widely used for the therapeutic treatment of viral infections, tumor growth and various chronic diseases such as multiple sclerosis. Antagonism between type I IFNs and IFN-gamma has been described in cells of the immune system, in particular in the activation of macrophages. To study the systemic effects of type I IFNs we used transgenic mice carrying a human IFN-beta (hIFN-beta) gene under the control of the rat insulin I promoter. These animals expressed high levels of hIFN-beta in beta-pancreatic cells, and the ability of the macrophages to respond to pro-inflammatory stimuli was analyzed. Transgenic mice exhibited an increased extravasation of cells to the peritoneal cavity after eliciting with thioglycollate broth. The expression of the inducible form of nitric oxide synthase and cyclooxygenase-2, two enzymes involved in inflammation, was impaired in transgenic animals challenged with lipopolysaccharide and IFN-gamma. Analysis of the mechanisms leading to this attenuated inflammatory response showed a decrease in the serum levels of TNF-alpha and an inhibition of the activation of the transcription factor NF-KB in various tissues. These results indicate that systemic administration of IFN-beta might influence the response to pro-inflammatory stimuli, in particular through the antagonism of IFN-gamma signaling.

Transgenic mice overexpressing insulin-like growth factor-II in beta cells develop type 2 diabetes.

During embryonic development, insulin-like growth factor-II (IGF-II) participates in the regulation of islet growth and differentiation. We generated transgenic mice (C57BL6/SJL) expressing IGF-II in beta cells under control of the rat Insulin I promoter in order to study the role of islet hyperplasia and hyperinsulinemia in the development of type 2 diabetes. In contrast to islets from control mice, islets from transgenic mice displayed high levels of IGF-II mRNA and protein. Pancreases from transgenic mice showed an increase in beta-cell mass (about 3-fold) and in insulin mRNA levels. However, the organization of cells within transgenic islets was disrupted, with glucagon-producing cells randomly distributed throughout the core. We also observed enhanced glucose-stimulated insulin secretion and glucose utilization in islets from transgenic mice. These mice displayed hyperinsulinemia, mild hyperglycemia, and altered glucose and insulin tolerance tests, and about 30% of these animals developed overt diabetes when fed a high-fat diet. Furthermore, transgenic mice obtained from the N1 backcross to C57KsJ mice showed high islet hyperplasia and insulin resistance, but they also developed fatty liver and obesity. These results indicate that local overexpression of IGF-II in islets might lead to type 2 diabetes and that islet hyperplasia and hypersecretion of insulin might occur early in the pathogenesis of this disease.

Pruritus in chronic hepatitis C: association with high serum bile acids, advanced pathology, and bile duct abnormalities.

Pruritus is a common symptom of chronic cholestatic liver diseases but is considered rare in chronic hepatitis. We observed pruritus to be an unusually common complaint in patients with advanced chronic hepatitis C. We reviewed the records of 175 chronic hepatitis C patients to identify patients with severe, diffuse, unexplained pruritus; 12 consecutive prospective patients undergoing liver biopsy for chronic hepatitis C served as controls. Assessment included laboratory biochemical tests and assessment of liver pathology by stage, grade, hepatic activity index, and a bile duct score. Pruritus was present in nine (5.1%) patients. Serum AST, ALT, alkaline phosphatase, GGTP, total bilirubin, and ferritin were similar in pruritics and controls. Pruritics had higher serum bile acids (2028.4 +/- 223.1 mmol/liter vs 423.1 +/- 194.3, P < 0.001), higher transferrin saturation (57.5 +/- 6.8% vs 33.2 +/- 3.3, P < 0.01), and lower HCV RNA by bDNA (24.5 +/- 12.7 x 10(5) vs 172.7 +/- 54.1 x 10(5), P < 0.05). Pathology revealed cirrhosis in 6/9 (66.6%) pruritics vs 1/12 (8.3%) controls (P < 0.01). Pruritics had higher pathologic stage (3.7 +/- 0.2 vs 2.2 +/- 0.4, P < 0.01), grade (4.4 +/- 0.2 vs 2.1 +/- 0.2, P < 0.001), activity index (14.3 +/- 1.9 vs 8.6 +/- 1.9, P < 0.025), and bile duct score (7.6 +/- 0.6 vs 4.7 +/- 0.4, P < 0.01). Of eight pruritics treated with IFN-alpha2b, two had complete ALT response and one relapsed. Pruritus followed a relapsing course and only three patients partially responded despite a variety of interventions. In conclusion, pruritus is a common complication of advanced CHC. Its presence is associated with high serum bile acids, advanced pathology and bile duct abnormalities. The clinical course of pruritus is relapsing and response to therapy is inconsistent. These features suggest that pruritus in CHC has a pathogenesis that may vary from that of chronic cholestatic diseases.

The breakthrough phenomenon during alpha-interferon therapy of chronic hepatitis C: incidence, management, and outcome.

OBJECTIVES: Some patients treated with alpha-interferon (alpha-IFN) for chronic hepatitis C (CHC) initially respond with normalization of ALT only to encounter a rise in ALT while still on the drug. This phenomenon is called breakthrough (BT). We reviewed our experience with BT to clarify its incidence, pathogenesis, management, and outcome. METHODS: Charts from 71 consecutive patients with CHC treated with alpha-IFN were reviewed. Forty of these patients were part of a study of 1-yr escalating dose alpha-IFN, initiated at 2 million units (MU) 3 times per week. Endpoints that were evaluated were: reachievement of normal ALT, complete response (CR) (defined as normal ALT at the end of therapy), and sustained CR maintained for 6 months after therapy. RESULTS: Twenty-one (29.5%) patients sustained 28 BT events. Thirteen (46.4%) BT events occurred during the first 6 months of a course of alpha-IFN therapy, and 15 (53.6%) occurred during months 7 through 12. Of patients experiencing BT, six (28.6%) completed their course of therapy with a CR, of which two (9.5%) were sustained. By comparison, of 22 patients who normalized ALT without BT, all completed their course with a CR by definition (p < 0.0001), and nine (40.9%, p < 0.05) had a sustained CR. Of 28 BT events, 13 (46.4%) were followed by reattainment of normal ALT. Of 16 BT events managed with continuation of the same dose of alpha-IFN, normal ALT was reachieved in seven (43.8%). Of 12 BT events managed with an escalation in alpha-IFN dose, six (50%) reachieved normal ALT. A full sequential series of hepatitis C virus RNA PCR from periods of elevated, normal, and again elevated ALT was available for 12 BT events. The pattern was +/+/+ in six, +/-/+ in five, and +/-/- in one. In one additional patient, an apparent BT was attributable to alpha-IFN-induced autoimmune hepatitis. CONCLUSIONS: BT is a common event that may occur at any point during alpha-IFN therapy of CHC. This may limit the benefits of maintenance strategies. After a BT event, normal ALT can be reestablished in about 50% of cases, although the chance of a sustained CR falls to less than 10%. No advantage was demonstrated for escalating the alpha-IFN dose after a BT event. Therefore, we recommend continuation of the same dose as the initial approach. We suspect that BT relates to nonspecific ALT fluctuation in some patients and to emergence of resistant hepatitis C virus strains in others. Other causes of ALT elevation must also be considered in patients with apparent BT.

Open label study of long-term effectiveness of cisapride in patients with idiopathic gastroparesis.

Cisapride induces acetylcholine release in cells of the myenteric plexus, thus promoting gastrointestinal motility. We studied the effects of cisapride on 11 patients with idiopathic gastroparesis. All had negative gastrointestinal endoscopy, normal glucose, and took no drugs capable of influencing motility. Most (9/11) were prior metoclopramide treatment failures. Patients' symptoms were scored (0-60) for pain, satiety, bloating, nausea, vomiting, and heartburn. All underwent a solid gastric emptying study using a Technetium-99-labeled egg meal and received placebo prior to cisapride. There were 10 females and one male with a mean (+/- SE) age of 37.8 +/- 2.6 years. Disease duration was 7.9 +/- 2.8 years. The dose of cisapride was 30-60 mg/day and the duration of therapy was 12.6 +/- 2.6 months (range 2.5-25 months). The symptom score improved on cisapride from 30.9 +/- 3.6 to 14.4 +/- 2.7 (P < 0.002 signed rank test). Emptying half-time improved from 113 +/- 4 min to 94 +/- 6 min, and 46.9 +/- 2.4% food remaining at 120 min decreased to 35.5 +/- 3.6% (both P < 0.05). Emptying half-time in normals was 68 +/- 5 min with 16.9 +/- 2.9% remaining at 120 min. Nine of 11 patients gained weight, with a mean increase of 6.7 +/- 1.6 lb (range 2-12 lb). We conclude that cisapride significantly reduces gastrointestinal symptoms and promotes weight gain in patients with idiopathic gastroparesis and is associated with improvement in solid gastric emptying. The drug is useful in patients who previously failed metoclopramide.

The safety and efficacy of gi endoscopy in patients with acute-leukemia - a review of 27 cases.

In the course of aggressive treatment for acute leukemia, the ensuing pancytopenia and intensive medical support may be accompanied by severe gastrointestinal (GI) complications. Therefore, to assess the safety and efficacy of GI endoscopy as a means of diagnosis, we analyzed the records of 16 patients undergoing 27 endoscopies a mean (+/-S.D.) of 18.4 +/- 11.9 days post chemotherapy. There were 6 procedures performed in patients with acute lymphocytic, 18 with acute myelogenous, including 3 with acute promyelocytic and 3 with blastic phase chronic myelogenous leukemia. 10/27 procedures were performed in patients with less than 1000 WBC/mm3 and 19/27 had less than 100,000 platelets. 15 patients had 25 upper endoscopies done for: bleeding (twenty-one), abdominal pain (two), and persistent vomiting (two). The principal bleeding sources were: esophagitis (eleven), Mallory Weiss tear (one), gastritis (three), gastric ulcer (one), duodenal ulcer (five). In the non-bleeding cases 2 exams were normal and the others had gastritis (one) and esophagitis (one). 15/25 procedures (64%) resulted in new diagnosis and 20/25 (80%) in additional therapies. 47% of patients undergoing upper GI endoscopy received specific new therapies as a result of that procedure. Nd: YAG laser photocoagulation was effective in stopping bleeding lesions in 4/6 cases. 10/12 bleeding patients had persistent or recurrent bleeding and 2 died from bleeding. None had surgery. Two patients underwent colonoscopy, both for colonic distention. One patient, who had been recently treated for Cl. difficile had submucosal petechiae. The other had non-specific colitis. No biopsies were done and both cases were successfully decompressed..No complications occurred from any GI endoscopy. We conclude that GI endoscopy can be safely performed in patients with acute leukemia, resulting in specific diagnoses and therapies. Esophagitis is a principal cause of GI bleeding in these patients. The role of therapeutic endoscopy in controlling bleeding is promising but requires further evaluation.

Increased superoxide production by polymorphonuclear leukocytes in systemic lupus erythematosus.

Normal and lupus PMN show an enhancement in superoxide production in vitro when stimulated with lupus serum. When N-formyl-methionyl-leucyl-phenylalanine (FMLP) was used, lupus PMN showed an O2- production of 2.1 nmol/min/10(7) cells, which is 5.2 times the response of normal PMN stimulated by FMLP. Our results show the existence of serum factors in SLE patients that can stimulate O2- production by PMN. Lupus neutrophils showed an increased response to membrane stimuli such as FMLP, capable of triggering the cell respiratory burst. Lupus neutrophils appeared more responsive to membrane stimuli. The serum and cellular factors seemed to indicate an increase rate of superoxide production by PMN in lupus patients, which could be relevant factors in the development of vasculitis and tissue damage.

Upper gastrointestinal bleeding following open heart surgery. Predominant finding of aggressive duodenal ulcer disease.

We reviewed our experience with endoscopically evaluated severe upper gastrointestinal hemorrhage following open heart surgery. Of 4892 patients undergoing open heart surgery, 18 (0.4%) sustained upper gastrointestinal hemorrhage requiring endoscopic evaluation. Endoscopy identified the source of bleeding in all cases. No significant complications of endoscopy were observed. Duodenal ulcers (DUs) were found in 16 (89%) of cases and were felt to be the source of bleeding in 15 (83%). Aggressive features, such as multiplicity, large size, or distal location were associated with 13 (81%) of the DU cases. Complications necessitated endoscopic or surgical therapy in eight (44%) patients with DUs. We conclude that aggressive DU disease accounts for the majority of severe upper gastrointestinal bleeding following open heart surgery.

Inhibition by opioids of phagocytosis in peritoneal macrophages.

We have tested the effect of prototypic opioid agonists on phagocytosis of sheep erythrocytes by mouse peritoneal macrophages. It was found that morphine and all the opioid peptides tested inhibited phagocytosis by a biphasic, naloxone-reversible mechanism. Delta agonists were the most effective inhibitors, suggesting that the response is mediated by a delta receptor. Chronic exposure to morphine apparently results in the development of tolerance since under these conditions the inhibitory effect of the opiate is abolished. These results are similar to previously reported effects of opioids on endocytosis in other systems, which suggests that this inhibition is part of a basic regulatory mechanism that has been conserved in evolution.

[Erythrocyte CR1 receptor reactivity in patients with systemic lupus erythematosus]. / Reactividad del receptor eritrocitario CR1 en pacientes con lupus eritematoso sistémico.

Erythrocytes from 42 systemic lupus erythematosus (SLE) patients and 80 healthy volunteers were tested for the immunoadherence (CR1) receptor reactivity, observed by hemagglutination (IAHA) when incubating erythrocytes and aggregated human gamma-globulin (AHGG)-complement in appropriate proportions. Reactivity was expressed as the highest two-fold dilution of AHGG (2n) that induced hemagglutination. Erythrocytes of 15 SLE patients (35.7%) showed reactivity compared with 70 normal controls (87.5%). Both groups showed a trimodal distribution of IAHA titers in accordance with the three phenotypic groups described by other authors. Of the healthy population 72.5% belong to the intermediate reactivity mode (2(6) to 2(8)) and 64.3% of the SLE patients to the low reactivity group (negative). There was no correlation between CR1 defective expression and conventional activity parameters. This erythrocyte receptor involved in the immunocomplex clearance process, which constitutes 95% of the circulating CR1, is another factor that contributes to the pathophysiology of the disease when it is defective.

Reactividad del receptor eritrocitario CR1 en pacientes con lupus eritematoso sistémico. / [Erythrocyte CR1 receptor reactivity in patients with systemic lupus erythematosus]

Erythrocytes from 42 systemic lupus erythematosus (SLE) patients and 80 healthy volunteers were tested for the immunoadherence (CR1) receptor reactivity, observed by hemagglutination (IAHA) when incubating erythrocytes and aggregated human gamma-globulin (AHGG)-complement in appropriate proportions. Reactivity was expressed as the highest two-fold dilution of AHGG (2n) that induced hemagglutination. Erythrocytes of 15 SLE patients (35.7

) showed reactivity compared with 70 normal controls (87.5

). Both groups showed a trimodal distribution of IAHA titers in accordance with the three phenotypic groups described by other authors. Of the healthy population 72.5

belong to the intermediate reactivity mode (2(6) to 2(8)) and 64.3

of the SLE patients to the low reactivity group (negative). There was no correlation between CR1 defective expression and conventional activity parameters. This erythrocyte receptor involved in the immunocomplex clearance process, which constitutes 95

of the circulating CR1, is another factor that contributes to the pathophysiology of the disease when it is defective.

[Neutrophil-dependent inflammatory reactions in systemic lupus erythematosus]. / Reacciones inflamatorias neutrofilo-dependientes en Lupus Eritematoso Sistémico.

We studied the possible role of polymorphonuclear neutrophil (PMN) aggregation in Systemic Lupus Erythematosus (SLE) by the capacity of sera from 32 lupus patients to induce in vitro normal PMN aggregation. Neutrophil aggregating activity (NAA) in this group was significantly greater than that found in 8 inactive SLE patients and in 8 controls. In patients with SLE, there was a positive correlation between disease severity and the quantitative measure of NAA. High levels of NAA were particularly characteristic of central nervous system SLE. These data suggest that the formation of intravascular leukoaggregates may contribute to morbidity in SLE. Normal PMN increase their spontaneous superoxide anion production (0.21 nmol/min 10(7) PMN) when stimulated with sera from SLE patients. Lupus PMN also show an enhancement of 100% in superoxide production in vitro when stimulated with lupus sera. When N formyl methionine leucyl phenylalanine (FMLP) was used, lupus PMN showed an O2-production of 2.1 nmol/min 10(7) which is 5-fold the response of normal PMN stimulated by FMLP. Our results show the existence of seric factors in SLE patients that can stimulate O2-production by PMN. Lupus neutrophils show an increased response to membrane stimuli such as FMLP, capable of triggering the respiratory burst. Lupus neutrophils appear more responsive membrane stimuli such as FMLP, capable of triggering the respiratory burst. Lupus neutrophils appear more responsive to membrane stimuli. The seric and the cellular factors seem to indicate an increased rate of superoxide production by PMN in SLE patients, which can be relevant to vasculitis and tissue damage.