Vitamin B12 treatment for delayed sleep phase syndrome: A multi-center double-blind study

Abstract  The active form of vitamin B₁₂ (methylcobalamin) has been reported to be effective on sleep-wake rhythm disorders. Previous studies, however, were performed under open trial, and the effect of vitamin B₁₂ has not been properly evaluated. The aim of this double-blind study was to investigate the efficacy of methylcobalamin on delayed sleep phase syndrome (DSPS). Methylcobalamin (3 mg/day) or placebo was administered for 4 weeks. The subjects were 50 patients with DSPS aged 13–55 years (26.8 ± 1.3), 27 of whom received the active drug while 23 received the placebo. No significant differences were observed between the 2 groups in subjective evaluations of mood or drowsiness during the daytime or in night sleep by sleep-log evaluation. These results indicate that 3 mg methylcobalamin administered over 4 weeks is not an effective treatment for DSPS.     

Influence of the genetic pattern and sex of mice in experimental paracoccidioidomycosis

Eight genetically different strains of mice were compared regarding the dissemination of Paracoccidioides brasiliensis to the lungs, liver and omentum/pancreas, DTH responses and specific antibody production at 16 weeks after intraperitoneal infection with Pb18, a virulent P. brasiliensis isolate. The degree of dissemination of the infection varied: B10.A and C57Bl/6, the most susceptible mouse strains, had positive cultures and high colony-forming unit (CFU) counts in all analysed organs. DBA/2 and A/Sn mice had negative cultures, being thus classified as the most resistant strains. CBA/J, C3H/HeJ, F₁(A/SnxB10.A) and BALB/c mice were regarded as relatively resistant, since discrete fungal growth was observed only in one or two of the studied organs. All mouse strains, except B10.A mice, produced specific DTH responses which did not seem to be associated with the severity of disease. Production of high levels of specific antibodies was found in all strains except in the DBA/2 and C57B1/6 mice. The influence of the host sex on the outcome of paracoccidioidomycosis was evident only in susceptible animals: female B10.A mice displayed lower CFU counts in the three examined organs, whereas no differences were found between male and female A Sn animals. The higher resistance of female B10.A mice was not accompanied by differences in their capacity to maintain a DTH reaction, nor in their production of antibody. This fact argues against the widely believed association of susceptibility to P. brasiliensis infection with both impaired DTH reactivity and increased humoral response.     

Effect of ageing on pancreatic hyperplasia after 90% proximal small bowel resection

The present study was performed to examine the effect of ageing on pancreatic hyperplasia observed after proximal small bowel resection (PSBR). Young and old Wistar rats were randomly assigned to two groups, which underwent either an approximate 90% PSBR or a jejunal and ileal transection (TRC). One week after the operation, the pancreatic wet weight and the protein, DNA and RNA content of the pancreas were all significantly higher in young PSBR rats than in young TRC rats. However, no differences were seen in the old rat groups. Plasma enteroglucagon levels were elevated in both young and old PSBR rats, but the ratio of increase between the PSBR and TRC groups was significantly higher in young rats. Plasma cholecystokinin and gastrin levels did not increase after PSBR in either the young or old rats. These findings suggest that pancreatic hyperplasia observed after PSBR is attenuated by ageing, probably due to an insufficient increase in plasma enteroglucagon levels.     

A Clinical Study of Acute Pancreatitis following Endoscopic Retrograde Cholangiopancreatography

Abstract: Endoscopic retrograde cholangiopancreatography (ERCP) has been established as a safe and effective examination for patients with pancreatobiliary diseases. Pancreatitis following ERCP is an extremely rare complication. However, once pancreatitis occurs, patients may deteriorate developing a severe condition. This study was designed to investigate the cause of this pancreatitis with the aim of minimizing complications. Six hundred and forty-nine patients underwent ERCP in our clinic, from January 1990 to December 1994. Six patients developed acute pancreatitis following the examination. Amounts of contrast medium used, examination durations, pancreatic duct diameters, the existence of chronic pancreatitis, the presence of para-papillary diverticulum, and the use of a brushing procedure on the pancreatic duct are discussed in this study. There was no significant difference in the amount of contrast medium used, examination duration or pancreatic duct diameter. Chronic pancreatitis was not related to the occurrence of acute pancreatitis following ERCP (p = 0.1352). The presence of para-papillary diverticulum was associated with a tendency to develop pancreatitis (p=0.0989). Use of the brushing procedure correlated significantly with the occurrence of acute pancreatitis (p= 0.0081). This technique is one of the most important methods of diagnosing pancreatic malignancy, and should be done with great care in examining cases of suspected malignancy.     

Inhibitory effect of inhaled procaterol on anaphylactic bronchoconstriction and thromboxane A2 production in guinea-pigs

This study was designed to examine whether an inhaled beta 2-agonist, procaterol, inhibits thromboxane A2 (TXA2) production induced by antigen challenge in passively sensitized guinea-pigs in vivo. Antigen-induced bronchoconstriction was markedly inhibited by pre-treatment with procaterol. Inhaled procaterol significantly reduced in a dose-dependent manner the increment in TXB2 concentration in bronchoalveolar lavage fluid obtained 5 min after antigen challenge. Aerosol administration of procaterol significantly inhibited bronchoconstriction induced by inhaled histamine. These results suggest that inhalation of procaterol has an inhibitory effect on antigen-induced TXA2 production as well as a protective effect against bronchoconstriction induced by bronchoactive agents.     

Management of meconium aspiration syndrome by tracheobronchial lavage and replacement of Surfactant-TA

Meconium aspiration syndrome creates mechanical airway obstruction with air trapping and atelectasis. Tracheobronchial saline lavage to dislodge meconium may precipitate respiratory distress, a wet lung appearance and respiratory failure. Two case studies are reported in which meconium aspiration resulted in mechanical obstruction and displacement of surfactant and in whom tracheobronchial saline lavage and artificial surfactant replacement reversed respiratory failure.     

Improvement of peripheral blood lymphocyte subsets in primary biliary cirrhosis after ursodeoxycholic acid therapy

Immunological abnormalities frequently observed in patients with primary biliary cirrhosis are considered to be related to the pathogenesis of this disease. We performed a prospective trial to evaluate whether immune mechanisms play a role in the effectiveness of ursodeoxycholic acid (UDCA) therapy. Fifteen female patients with primary biliary cirrhosis were followed for 1 year and were then treated with UDCA (600 mg/day) for another year. Laboratory tests, including peripheral blood lymphocyte subsets assessed by dual colour fluorescence analysis using monoclonal antibodies against respective T cell markers, were evaluated at the beginning of the study, at the start of therapy and at the end of therapy. In primary biliary cirrhosis, the proportion of cytotoxic T cells, suppressor inducer T cells and αβ-receptor bearing T cells were significantly lower than in healthy controls. No significant changes were observed in the proportions during the year before the therapy. These reductions, however, recovered to normal ranges after 1 year of UDCA therapy. These changes were associated with an improvement in the serum levels of aspartate aminotransferase, alkaline phosphatase, γ-globulin and IgM. The close correlation between the improvement in the imbalance of lymphocyte subsets after the therapy and the clinical status suggests that an immunological process may play a role in the effectiveness of therapy in primary biliary cirrhosis.