The involvement of an opiate mechanism in the sensitized behavioral deficit induced by early chronic variable stress: influence of desipramine

The influence of early chronic variable stress (CVS) associated with persistent desipramine (DMI) administration was examined on escape performance. Animals were exposed to CVS and 1 day later administered DMI (5 mg/kg, i.p. twice a day) or vehicle (VH) during six consecutive days. Escape performance was assessed over 24 h following inescapable shock (IS) exposure. Higher escape failures were observed in CVS shocked rats compared with unstressed shocked animals. DMI normalized escape failures in both groups. In order to investigate the role of an endogenous opiate mechanism presumably activated by CVS exposure in this behavioral deficit, rats were administered naltrexone (NAL, 2 mg/kg i.p.) or VH prior to each daily stressor of the CVS regime. NAL pretreatment blocked escape failures performed only by CVS shocked rats. In addition, animals were daily administered morphine (MOR, 10 mg/kg, i.p.) or VH during seven consecutive days and subsequently administered DMI. A significant increase in escape deficit in shocked rats was observed after chronic MOR but not following the associated treatment with MOR and DMI. These behavioral data suggest that early experience with a CVS facilitated the onset of escape deficit induced by a brief IS event, an effect that can be prevented by chronic DMI. Furthermore, this sensitized escape deficit response seems to be partially modulated by the previous activation of an opiate mechanism.     

A to Z: Vitamin A and zinc,the miracle duo

Dietary micronutrients such as vitamins and trace minerals are known modulators of host immune responses against common pathogens. In this respect, vitamin A and zinc have recently received increased attention. Severalin vivo andin vitro studies suggest that vitamin A may be a critical player in the mucosal immune responses in the respiratory and gastrointestinal tracts, particularly in undernourished children. The effect may be mediated primarily by stabilization of the membrane of mucosal epithelial cells, as well as enhanced leukocyte functions. The beneficial effect of vitamin A therapy in reducing measles-associated morbidity and mortality suggests its crucial role in defenses against viral pathogens. Zinc is also known affect leukocyte functions such as phagocytosis and T-lymphocyte-mediated immune responses. However, unlike vitamin A, zinc has been investigated primarily for its effects on bacterial infections. Dietary supplementation or therapeutic treatment with vitamin A and zinc may be a cheap yet effective means of preventing or treating infections in highly susceptible populations. Additional studies, however, are required to better define the types of pathogens and the specific human populations that may benefit from such therapy.     

Liposomally-entrapped ganciclovir for the treatment of cytomegalovirus retinitis in AIDS patients

Treatment of retinitis by cytomegalovirus (CMV) in AIDS patients requires frequent repetitive injections of intravitreal ganciclovir (GCV). This study was undertaken to establish experimentally whether the intravitreal application of liposomally-entrapped GCV could prolong intraocular therapeutic levels when compared with the intravitreal injection of free GCV, and the clinical effectiveness of this approach in AIDS patients. Intraocular concentration of GCV was determined by means of an ELISA test in rabbit vitreous 2, 3, 7, and 14 days after a single intravitreal injection of either different doses of the free drug (0.2–20 mg) or 1 mg of liposomally-entrapped GCV. After 72 h, only the vitreous of rabbits injected with doses of free GCV greater than or equal to 5 mg showed therapeutic levels of the drug; no GCV was detected after 72 h with any of the doses applied. Moreover, the microscopic study revealed GCV-induced damage in retinal structures in the animals injected with a free GCV dose greater than or equal to 15 mg. Intravitreal injection to rabbits of 1 mg of liposomally-encapsulated GCV showed no retinal toxicity at any of the time points studied, and therapeutic levels were detected up to 14 days after injection (4.67 ± 0.39 g/ml). Five AIDS patients suffering CMV retinitis were injected with 0.5 mg of liposomally-entrapped GCV (2 mg of lecithin). Complete remission of the CMV retinitis was observed already at the third injection of 0.5 mg GCV (one per week) and relapse did not occur during the 2–4 month follow-up of the patients. In view of the results presented, it can be concluded that intravitreal injection of liposomally-encapsulated GCV increases the time period required for reinjections in the treatemnt of CMV retinitis.Abbreviations AIDS acquired immunodeficiency syndrome - AZT zidovudine - CMV cytomegalovirus - GCV ganciclovir     

Esophagogastrectomy for adenocarcinoma of the cardia. Ten years' experience and current approach.

During a 10-year period, 94 surgical resections for adenocarcinoma of the cardia (75 "curative" and 19 palliative) were performed using three primary approaches: Group I (46 curative, 14 palliative), esophagogastrectomy performed through a left thoracotomy or left thoraco-abdominal incision; Group II (17 curative, 4 palliative), resection done through two separate incisions (abdominal and thoracic) with delayed reconstruction between two and three months later; and Group III (12 curative, 1 palliative), resection, also through abdominal and thoracic incisions, with simultaneous reconstruction. Operative mortality in the 75 procedures done for cure was 19.5%, 18%, and 8.3% in Groups I, II, and III, respectively. Microscopic residual tumor at the line of resection was 56%, 12%, and 8%. Free margins less than 3 cm had the same local recurrence rate (21%, 6%, and 8%) within 18 months as did margins with residual microscopic tumor. The length of time from operation to first regular meal was 12, 110, and 7 days, respectively. Wide resection with subtotal esophagectomy and simultaneous reconstruction is advocated.     

Nonsperm cells in human semen and their relationship with semen parameters

The prevalence and clinical significance of leukocytes (WBC) and immature germ cells in semen is currently a matter of controversy. The aim of this work was to assess the prevalence of leukocytospermia in semen samples from Venezuelan men and its possible effects on sperm parameters. The concentration of WBC and round cells (RC) was evaluated in 118 semen samples from 19 fertile subjects (group 1), 62 infertile patients (group II), and 37 men with varicocele (group III). Semen WBC concentration was assessed by peroxidase assay. Twenty-six (22%) of the total samples had more than 10 WBC/mL semen. Twenty of the infertile men had leukocytospermia (32%) compared with 16% in the fertile group and 8% in the varicocele group. Semen RC concentration was lower than 5 x 10(6)/mL in all groups but, in groups II and III was significantly higher compared with group I. Infertile men had the highest WBC concentration. WBC concentration was negatively correlated with progressive motility, percentage of morphologically normal sperm, and hypoosmotic swelling test in infertile men but not in the varicocele group. In this group a negative correlation was obtained between immature germ cells and normal sperm morphology. The data show that leukcytospermia occurs frequently in infertile patients and is associated with poor semen quality parameters. In contrast, in men with varicocele, the increased number of immature germ cells might play a pivotal role in the pathogenesis of abnormal spermatozoa.     

Lymphangioma of the spermatic cord

We report a new case of spermatic cord lymphangioma in a infant 2 years old. The initial diagnosis was funicular hydrocele. The treatment was the local excision of tumor and the diagnostic was histological. Postoperative course was excellent. Must be explored the transillumination of the mass which would have led us to think other the diagnosis different from that of the cord hydrocele before the operation since it would have given negative. During the operation, must the assured that the cystic anomaly is limited to spermatic cord, to evite recurrences in the postoperative course.     

Pseudomixoma peritoneal tipo adenomucinosis peritoneal diseminada con imágenes radiológicas atípicas

Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management.     

Relationship between tumor recurrence and the expression of the p53 gene in primary superficial transitional carcinoma of the bladder

Contribution of 60 patients with primary surface transitional cell tumours of the bladder where nuclear expression of p53 protein was prospectively studied and compared to known prognostic factors in an attempt to find out its role in the development of relapses. An statistically significant relationship was found between the protein expression and cytology, tumoral multifocality, stage, relapse development and tumoral progression. It can be concluded that expression of this protein can be of use as relapse predictor.     

Screening for complement deficiency in bacterial meningitis

Seventy-seven children with bacterial meningitis were screened for complement deficiency. Both the classical and the alternate pathways were normal in 75 patients. Transiently reduced total haemolytic activity of the classical pathway was documented in a boy with meningococcal meningitis. Total haemolytic activity of both the classical and the alternate pathways were reduced in another patient with pneumococcal meningitis: individual complement components determination indicated predominant activation of the alternate pathway.     

Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats

Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is a contaminant of the human food supply, particularly in parts of Africa and Asia. AFB1-induced changes in gene expression may play a part in the development of the toxic, immunosuppressive and carcinogenic properties of this fungal metabolite. An understanding of the-role of AFB1 in modulating gene regulation should provide insight regarding mechanisms of AFB1-induced carcinogenesis. We used three PCR- based subtractive techniques to identify AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential display PCR (DD-PCR), representational difference analysis (RDA) and suppression subtractive hybridization (SSH). Each of the three techniques identified AFB1- responsive genes, although no individual cDNA was isolated by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH were found to represent eight genes that are differentially expressed as a result of AFB1 exposure. Genes whose mRNA levels were increased in cultured primary rat hepatocytes after AFB1 treatment were corticosteroid binding globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin, C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When liver RNA from AFB1-treated male F344 rats was evaluated for transferrin, CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen. Analysis of the potential function of these genes in maintaining cellular homeostasis suggests that their differential expression could contribute to the toxicity associated with AFB1 exposure.