Genetic location of the gene (ush) specifying periplasmic uridine 5'-diphosphate glucose hydrolase (5'-nucleotidase) in Escherichia coli K-12

Further genetic mapping to two- and three-factor crosses show that the ush gene is closely linked to two other genes hemG and pisA, and that the probable gene order is proC-hemG-plsA-ush-gal.     

Influence of infection on patent ductus arteriosus and chronic lung disease in premature infants weighing 1000 grams or less

OBJECTIVES: To test the hypotheses that (1) infection increases ductal dilatory prostaglandins and inflammatory mediators that may influence the closure of a patent ductus arteriosus (PDA), increasing the incidence of late episodes of PDA (after 7 days) and the rate of closure failures, and (2) the concurrence of PDA and infection increases the risk of chronic lung disease (CLD). METHODS: One hundred fourteen premature infants (birth weight, 500 to 1000 gm) were prospectively assessed for PDA and infection. Serum levels of 6-ketoprostaglandin F1 alpha and tumor necrosis factor alpha were measured routinely in all infants and when PDA or infection was present. Multivariate assessment of risk factors for PDA closure failure and for CLD was done by logistic regression, and expressed as an odds ratio and as 95% confidence intervals. RESULTS: Late PDA episodes were more frequent in infants with infection than in those without infection. A temporally related infection (<5 days between both diagnoses) was associated with an increased risk of PDA closure failure (odds ratio, 19.1 (confidence interval, 4 to 90)). In addition to birth weight and the severity of initial respiratory failure, PDA and infection increased the risk of CLD (odds ratio, 11.7 (confidence interval, 1.7 to 81) for PDA; odds ration, 3.1 (confidence interval, 1 to 11) for infection). Furthermore, when both factors were temporally related, they further increased the risk of CLD (odds ratio, 29.6 (confidence interval, 4.5 to >100)). Infants with infection and those with PDA had higher levels of 6-ketoprostaglandin F1 alpha than did control subjects. Levels of tumor necrosis factor alpha were also elevated in infants with infection and in those with late PDA. CONCLUSIONS: Infection adversely influences PDA outcome by increasing the risk of late ductal reopening and PDA closure failures. Increased levels of prostaglandins and tumor necrosis factor alpha in infants with infection may explain the poor PDA outcome. The concurrence of PDA and infection potentiates their negative effects on the risk of CLD.     

Evidence that cellular immune responses to soluble and membrane associated antigens are independently regulated during human schistosomiasis mansoni

The glucagonoma syndrome is a rare disorder characterized by weight loss, necrolytic migratory erythema (NME), diabetes, stomatitis, and diarrhea. We identified 21 patients with the glucagonoma syndrome evaluated at the Mayo Clinic from 1975 to 1991. Although NME and diabetes help identify patients with glucagonomas, other manifestations of malignant disease often lead to the diagnosis. If the diagnosis is made after the tumor is metastatic, the potential for cure is limited. The most common presenting symptoms of the glucagonoma syndrome were weight loss (71%), NME (67%), diabetes mellitus (38%), cheilosis or stomatitis (29%), and diarrhea (29%). Although only 8 of the 21 patients had diabetes at presentation, diabetes eventually developed in 16 patients, 75% of whom required insulin therapy. Symptoms other than NME or diabetes mellitus led to the diagnosis of an islet cell tumor in 7 patients. The combination of NME and diabetes mellitus led to a more rapid diagnosis (7 months) than either symptom alone (4 years). Ten patients had diabetes mellitus before the onset of NME. No patients had NME clearly preceding diabetes mellitus. Increased levels of secondary hormones, such as gastrin (4 patients), vasoactive intestinal peptide (1 patient), serotonin (5 patients), insulin (6 patients, clinically significant in 1 only), human pancreatic polypeptide (2 patients), calcitonin (2 patients) and adrenocorticotropic hormone (2 patients), contributed to clinical symptoms leading to the diagnosis of an islet cell tumor before the onset of the full glucagonoma syndrome in 2 patients. All patients had metastatic disease at presentation. Surgical debulking, chemotherapy, somatostatin, and hepatic artery embolization offered palliation of NME, diabetes, weight loss, and diarrhea. Despite the malignant potential of the glucagonomas, only 9 of 21 patients had tumor-related deaths, occurring an average of 4.91 years after diagnosis. Twelve patients were still alive, with an average age follow-up of 3.67 years.     

Therapeutic approaches to primary and secondary brain tumours

INTRODUCTION: This study examined the long-term effects of hysterectomy, with and without bilateral oophorectomy, and treatment with estrogen replacement on bone mineral density in older hysterectomized women. METHODS: Subjects were 346 women 60-89 years of age, who were participants in the Rancho Bernardo Study and attended a follow-up clinic visit in 1988-1991. Bone density was measured at the ultradistal wrist, midshaft radius, lumbar spine and hip. RESULTS: Of these women, 182 had a hysterectomy with conservation of one or both ovaries and 164 had a hysterectomy with bilateral oophorectomy. Current estrogen users had the highest bone densities; those who never used estrogen replacement had the lowest. Only 9.1% of oophorectomized women, compared to 19.2% of those with ovarian conservation had never used estrogen (P < .01). After adjustment for covariates including estrogen replacement therapy, hysterectomized women with ovarian conservation had marginally higher bone densities at the wrist (P < .09) and spine (P < .06) than oophorectomized women. We found significant differences only among women currently using estrogen (P < .05 for wrist and P < .01 for spine densities, respectively). Bone density did not differ at any site by oophorectomy status among past or never users of estrogen. CONCLUSIONS: Hysterectomized women who use estrogen replacement therapy have better bone density, regardless of a bilateral oophorectomy. In addition, bilateral oophorectomy may not have a long-term negative effect on bone density; hysterectomized women who do not use estrogen appear to have equivalent bone density whether or not they had a bilateral oophorectomy.