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B Stoll

Publications and source records attributed to B Stoll.

68 records · Page 4Linked to original sources
PubMed1988

Osmotic pressure measurements of the ligand-linked dissociation equilibrium of human oxyhemoglobin.

The tetramer/dimer equilibrium of human oxyhemoglobin has been measured by an osmometric method as a function of pH, chloride and 2,3-bisphosphoglycerate concentrations at 21 degrees C. The binding constants of chloride and 2,3-bisphosphoglycerate to the tetramer and the dimer were thus evaluated at various pH values. 2,3-Bisphosphoglycerate is bound to the dimer more strongly than to the tetramer. The dimer has a second binding site for 2,3-bisphosphoglycerate. The data for 2,3-bisphosphoglycerate binding were corroborated by direct binding measurements with the ultrafiltration method.

2,3-Diphosphoglycerate↗
PubMed1988

Enterotoxigenic Escherichia coli diarrhea in an endemic area prepares the intestine for an anamnestic immunoglobulin A antitoxin response to oral cholera B subunit vaccination.

We examined whether infection with enterotoxigenic Escherichia coli (ETEC) producing the heat-labile enterotoxin (LT) can prime the gut immune system to respond more efficiently to the immunologically related cholera B subunit component of a recently developed oral B subunit-whole-cell cholera vaccine (B-WCV). Nine Bangladeshi adults who had been hospitalized for watery diarrhea caused by LT-producing ETEC were given a single oral immunization with B-WCV on day 28 after hospital admission. The vaccine preparation used was adjusted to contain a lower-than-usual dose of B subunit, which had been found in previous studies to elicit a significant gut mucosal immunoglobulin A antitoxin response mainly in individuals with previous toxin-specific priming of their gut immune system. For comparison, nine patients convalescing from severe cholera disease and eight healthy subjects with no recent history of either cholera or ETEC infection were given the same oral vaccination with B-WCV. Vaccination in the ETEC convalescents induced an immunoglobulin A antitoxin response in intestinal lavage fluid which was comparable with that in the vaccinated cholera convalescents and superior to that in the vaccinated, previously uninfected controls. By contrast, only the cholera patients responded with anamnestic-type anti-cholera lipopolysaccharide antibody titer rises in the intestine after vaccination. These data support the specificity of the anamnestic anti-cholera toxin response in the ETEC patients after vaccination with cholera B-WCV.

Bacterial Toxins↗
PubMed1986

Breast feeding as a determinant of severity in shigellosis. Evidence for protection throughout the first three years of life in Bangladeshi children.

Little is known about the effect of breast feeding upon the severity of illness due to specific diarrheal pathogens. Using a systematically sampled and evaluated population of children aged less than 3 years, who attended a diarrheal disease hospital in Bangladesh, the authors performed a case-control study that assessed whether breast feeding reduces the severity of illness in shigellosis. From 540 children presenting with shigellosis between 1980-1982, they created a group of cases (n = 53) with severe illness and controls (n = 487) with non-severe illness. Overall, the odds ratio relating breast feeding to the severity of shigellosis (0.49, p = 0.01) suggested a substantial mitigating effect of breast feeding upon clinical severity. The high degree of protection against severe shigellosis was evident for breast-fed children up to 35 months of age, as well as for children at high risk for death because of severe malnutrition or measles. Because shigellosis continues to account for substantial morbidity and mortality in children in developing countries, the results support prolonged breast feeding in these settings.

Bangladesh↗
PubMed1985

Fourteen years of shigellosis in Dhaka: an epidemiological analysis.

We examined whether the proportion of Shigellae patients among diarrhoeal cases, the distribution, species, case-fatality rates and hospital visits changed over time in Dhaka. We isolated 19639 Shigella strains from 822812 diarrhoea cases treated at the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), between 1969 and 1982. The number of cases increased from 209 (2.5%) in 1969 to 4833 (7.7%) in 1976. Extrapolating from a 4% vigorous systematic sample of ICDDR,B hospital visits shigellosis cases and their proportion among diarrhoea cases increased to more than 9500 (12.0%) in 1981. The prevalence of various shigellae species altered over time. For example: in 1969 Shigella flexneri predominated in 74% of all Shigella cases; in 1973 Shigella dysenteriae accounted for 56%, and in 1981 Shigella flexneri again predominated (75%). More than 20% of all Shigella isolations were from infants: 60% in males and 40% in females. Over 7% of severe cases of Shigella infection referred from the outpatient department and admitted for treatment died. Nearly 40% of all the Shigella deaths were in infants of less than a year old while 49% were in 1-4 year old children. Increasing prevalence of shigellosis appears to be an important cause of diarrhoea in Dhaka especially among children. Areas with poor sanitation and water supply had higher prevalence. However, hospitalized cases represented a fraction of the actual problem. Resistance to antibiotics appears to be increasing and the development of new drugs and preventive methods within economic reach of less developed countries are crucial for reduction of the disease and related deaths.

Adolescent↗
PubMed1985

Presence of colonization factor antigens on fresh isolates of fecal Escherichia coli: a prospective study.

In Dhaka, Bangladesh, fresh isolates of Escherichia coli from 197 patients with diarrhea were investigated for production of enterotoxin and possession of colonization factor antigen (CFA) I or II. Enterotoxigenic E. coli (ETEC) was isolated from 34% of the patients, and of the 67 enterotoxin-positive strains, 75% carried CFAs. Among 68 healthy control persons no strains positive for both enterotoxin and CFA were found. The CFAs in general were restricted to certain serotypes of E. coli. In a subgroup of patients, part of an ongoing surveillance study, mixed infection was seen in 23% of those from whom recognized pathogens were identified. There was a tendency to more severe dehydration when the two virulence factors, enterotoxin and CFA, were simultaneously present.

Antigens, Bacterial↗
PubMed1980

Isolation of Campylobacter fetus subsp. jejuni from Bangladeshi children.

To determine the prevalence of infection with Campylobacter fetus subsp. jejuni in Bangladesh, culture surveys were conducted among three populations. In Dacca, Campylobacter was isolated from 5.2% of 97 individuals with clinical dysentery and from 12.3% of 204 patients with only diarrhea. This difference may have resulted from a greater representation of young children in the second group. Campylobacter was isolated from 17.7% of the 141 healthy village children aged 1 to 5.5 years and from 38.8% of the 1-year-old children. More infected children (48%) had a history of recent diarrheal illness than did a group of matched controls (20%; P = 0.016). These findings suggest that campylobacter infection is common for Bangladeshi children. However, this organism may not cause diarrheal illness in all instances in which it is isolated.

Adolescent↗
PubMed1977

[The effect of chlorhexidine gluconate on plaque and gingivitis].

In a clinical study, the influence of chlorhexidine digluconate (0.1%) on the incidence of dental plaque and gingivitis was examined in subjects with insufficient personal oral hygiene. Statistical evaluation showed that compared to a placebo, chlorhexidine digluconate had a significant plaque inhibiting effect. The gingivo-therapeutic effect of this substance was statistically significant.

Biguanides↗
PubMedDate not supplied

Best medical practice: viewpoint of a UK oncologist.

In a clinician's view, best medical practice has two distinct meanings in a tax-funded health system: optimal management as expected by the individual patient; or, the best possible within the economic limits dictated by the society. Based on this viewpoint, this article represents an oncologist's perspective on the meaning of best medical practice in the management of patients suffering from cancer, the extent to which it is achieved in the UK health system, and how far some of the present deficiencies may be overcome. There is urgent need for medical audit in the management of cancer patients in the UK because the traditional clinical freedom of doctors can lead to wide variations in management without corresponding differences in outcome as measured by benefit to the patient. We need consensus by physicians on the guidelines for optimal management of different types of cancer at various stages, both to avoid overtreatment of the individual patient and also to direct scarce resources to their most effective use. Physicians also need to agree on guidelines for giving priority to one patient over another when resources are limited, and such criteria need to be approved by society at large. The public must accept that in a non-explicit rationing system, each individual competes with every other. In the case of even more difficult ethical choices, a multidisciplinary national committee is required to advise on decision-making and its views need to be debated by the general public.

Clinical Protocols↗
PubMedDate not supplied

Effect of hepatocyte swelling on microtubule stability and tubulin mRNA levels.

Incubation of isolated rat hepatocytes under conditions known to induce cell swelling caused several alterations in microtubule physiology. As shown by immunofluorescence microscopy experiments in the absence and presence of triethyllead or colchicine (two well-established microtubule inhibitors), an apparent stabilization of the microtubule network became evident in hepatocytes exposed to hypotonic (190 mosmol/L) conditions. A similar stabilizing effect was also observed upon cell swelling induced by addition of insulin (100 nmol/L) or glutamine (10 mmol/L). The differential microtubule stabilities were not attributed to a differential incorporation of the antimicrotubular agents into hepatocytes as shown by [3H]colchicine-uptake experiments. The swelling-induced alterations of microtubules may contribute to the swelling-induced changes of liver cell function: in perfused rat liver it was found that the established inhibitory effect of hypotonic cell swelling on hepatic proteolysis was largely abolished in presence of colchicine. Tubulin mRNA levels increased by 1.9-, 2.1- and 2.7-fold in isolated hepatocytes being exposed for 120 min to hypotonic medium, insulin, or glutamine, respectively. The results suggest an involvement of microtubular structures in the regulation of liver metabolism in response to alterations of the cellular hydration state.

Animals↗