A mouse model linking viral hepatitis and salivary gland dysfunction

Objective:  Viral hepatitis is known to cause xerostomia in humans, but this has not been reported in an animal model. We report a severe, acute, highly reproducible saliva deficiency occurring in BALB/c mice as a result of experimental viral hepatitis.
Materials and Methods:  BALB/c mice, splenectomized or carrying genetic mutations to detect immunological contributions to the saliva deficiency syndrome, were infected intraperitoneally with a non-lethal dose of murine cytomegalovirus. Pilocarpine-stimulated saliva volumes were determined between 0 and 15 days after infection. Salivary gland, liver, spleen, and sera were analyzed for the presence of virus, cytokines, inflammatory infiltrates, and tissue damage.
Results:  Saliva deficiency was detectable 2 days after cytomegalovirus infection, peaked at 88% below normal by day 7, and resolved partially in all mice by 15 days postinfection as sialoadenitis increased. Neither salivary gland viral titers, sialoadenitis, splenectomy, nor systemic inflammatory markers correlated with hyposalivation severity. Elevated liver enzymes did correlate with hyposalivation, and mice genetically resistant to murine cytomegalovirus-induced hepatitis were significantly protected.
Conclusions:  Murine cytomegalovirus-induced salivary gland dysfunction is biphasic, with an acute hepatitis-associated phase and a later sialoadenitis-associated phase. Acute murine cytomegalovirus infection of BALB/c mice may provide a model for investigation of hepatitis-associated xerostomia.     

Salmonella meningitis and its complications in infants

OBJECTIVE: To review the presenting features, complications and outcome of infants with Salmonella meningitis. METHODOLOGY: Retrospective review of all cultures of cerebrospinal fluid positive for bacteria in children below 12 years of age, processed at the Department of Medical Microbiology, University of Malaya Medical Centre, Kuala Lumpur from 1973 to 1997. Records of all cases positive for Salmonella species were retrieved and studied. RESULTS: Thirteen infants aged 3 days to 9 months with Salmonella meningitis were included. The median age of onset of symptoms was 4 months. The clinical and laboratory features were similar to other causes of bacterial meningitis. Salmonella enteritidis was the commonest serotype isolated. Nine infants developed fits, six of which were difficult to control. Other complications noted were hydrocephalus (five), subdural effusions (four), empyema (three), ventriculitis (two), intracranial haemorrhage and cerebral abscess (one each). The use of ampicillin and/or chloramphenicol and inadequate duration of therapy resulted in recrudescence or relapse in five infants. The overall mortality was 18%. The presence of empyema, intracerebral abscess, ventriculitis, hydrocephalus, and intracranial haemorrhage were associated with adverse neurodevelopmental sequelae or death. More than half of those who survived had normal long-term outcome. CONCLUSION: Infants who developed neurological complications as a result of Salmonella meningitis had significant mortality and adverse long-term neurodevelopment outcome.     

Depot-medroxyprogesterone acetate in anticoagulated patients with previous hemorrhagic corpus luteum

Objective?To investigate the safety of depot-medroxyprogesterone acetate (DMPA) in women of reproductive age with prosthetic heart valves, as well as the impact of DMPA on the prevention of hemorrhagic corpus luteum in these patients with previous bleeding events.

Methods?In this prospective study we enrolled 13 patients who were receiving chronic anticoagulation for prosthetic heart valves, and who suffered from ovarian bleeding. After the initial bleeding episode(s), DMPA was initiated with the intent of preventing recurrent bleeding events by means of ovulation suppression. Follow-up included close monitoring of anticoagulation intensity, lipid profile, measurement of systolic and diastolic blood pressures and weight, and a general physical and gynecological examination.

Results?Of the participating 13 patients, one stopped DMPA after the third injection because she wanted to have a child. Among the remaining 12 women, over a mean follow-up of 39.9 months all patients were well and no hemorrhagic corpus luteum was observed. During the follow-up, anticoagulation intensity, assessed by the international normalized ratio (INR), was in the optimum therapeutic ranges at all times (range 2.5–3.5), except for values of 4.6, 5.8 and 5.9 in three patients at 9, 12 and 24 months, respectively. With regard to lipid profile, we observed a significant decrease in high-density lipoprotein cholesterol levels at 12 months, and significant increases in total cholesterol and triglyceride levels after 30 months compared to baseline serum levels. No significant changes were observed in serum low-density lipoprotein cholesterol levels. Mean body weight was higher at months 12 and 30, compared with baseline values (p?>?0.05).

Conclusion?DMPA, which is an effective contraceptive agent, can be used to prevent bleeding from the corpus luteum by means of ovulation suppression in anticoagulated patients with prosthetic heart valves. However, meticulous surveillance should be provided during the follow-up, including close monitoring of anticoagulation intensity and lipid profile.     

Torsion of the upper lobe in pneumothorax

A rounded density is occasionally seen hanging down from the hilus in the presence of a large pneumothorax. To find an explanation for this appearance, the authors obtained a right-sided bronchogram on a baboon, after which they induced pneumothorax on the same side. This experiment demonstrated that the rounded density is formed by a twisted and atelectatic upper lobe.     

Presence of the red cell alloantibody anti-E in an 11-week-old infant

The development of red cell (RBC) alloantibodies in infants less than 4 months of age is believed to be rare. Though there are no well-documented published accounts, the formation of alloanti-E in a multiply transfused 11-week-old infant is reported here. The infant, blood group B, D +, developed necrotizing enterocolitis and renal failure requiring 31 transfusions of washed and unwashed RBCs (group B and group O), as well as fresh-frozen plasma and platelets. Six weeks after the first blood transfusion, alloanti-E was detected. The anti-E weakly agglutinated R2R2 screening RBCs at 37 degrees C and sensitized these RBCs to react with anti-IgG. The infant's RBCs were typed as E-. Passive transfer of alloanti-E was ruled out by the negative antibody screening tests of each donor unit and the absence of any RBC alloantibodies in the mother's serum. Stored samples of the infant's sera were tested, and anti-E was shown to be present approximately 11 days after exposure to a known E+ RBC unit. The appearance of alloanti-E in this time frame is consistent with a secondary immune response. Primary immunization most likely took place in the first 4 weeks of transfusion therapy.     

The antiatherogenic effects of components isolated from pollen Typhae

Based on the results of previous investigations that pollen Typhae, a Traditional Chinese Medicine, Had antiatherogenic effects, several components were isolated successively from the drug and their effects on porcine aortic endothelial cell (EC) and smooth muscle cell (SMC) cultures as well as on platelet aggregation were examined. 12 components isolated from Pollen Typhae have been identified on their chemical structures and biological effects. 4 of them showed different evident antiatherogenic effects. 1) Isorhamnetin-3-O-rhamnosyl-glucoside could stimulate EC to produce tPA and PGI; 2)Quercetin-3-O-neohesperidose could protect EC from injury by fibrin, as well as raise tPA activity; 3)β-Sitosterol palmitate could inhibit SMC proliferation and 4) β-Sitosterol glucoside showed an inhibitory effect on platelet aggregation. These results would provide some information for the search of new drugs in the treatment and prevention of atherosclerosis.     

Studies of in vitro red cell autoantibody production in normal donors and in patients with autoimmune hemolytic anemia

The in vitro production of red cell autoantibodies (RBC AuAbs) has been investigated for better understanding of the pathogenesis of autoimmune hemolytic anemia (AIHA). Peripheral blood mononuclear cells (PBMNCs) were isolated and cultured for 14 days with or without added pokeweed mitogen (PWM), autologous RBCs, methyldopa, procainamide, and alpha-methylnorepinephrine. Also, isolated B cells were infected with Epstein-Barr virus (EBV) to produce polyclonal B-cell lines. Supernatants were tested for IgG and IgM RBC AuAbs by use of 125I-staphylococcal protein A (SPA). RBC AuAbs were detected in PBMNC cultures without additives to the culture medium of four of eight patients who had warm-antibody AIHA or a positive direct antiglobulin test (DAT) without hemolytic anemia. In two of these patients, RBC AuAb production was augmented by the addition of PWM, and in two additional patients, RBC AuAbs were detected only after the addition of PWM. Supernatants from PBMNC cultures from three of four normal donors produced RBC AuAbs independent of the presence of PWM; in two of these subjects, PWM augmented production of RBC AuAbs. PBMNC cultures from three DAT-negative patients with systemic lupus erythematosus produced RBC AuAbs, one in the presence of PWM and two in its absence. With one exception, there was no augmentation of AuAb production by the addition to the culture system of autologous RBCs or drugs. EBV infection of B cells from four patients with AIHA and four normal persons yielded B-cell lines secreting RBC AuAbs. The quantity of RBC AuAb after a 24-hour culture of EBV-transformed B cells was significantly greater in cultures from four patients who had AIHA than in cultures from four normal persons.(ABSTRACT TRUNCATED AT 250 WORDS)