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Biomedical subjects

B Bergman

Publications and source records attributed to B Bergman.

At least 19 recordsLinked to original sources
PubMed1992

Ultrastructural and chemical assessment of poly-beta-hydroxybutyric acid in the marine cyanobacterium Trichodesmium thiebautii.

We report here on the occurrence and quantities of poly-beta-hydroxybutyric acid (PHB) in natural populations of the marine cyanobacterium Trichodesmium thiebautii. A diurnal variation in the shape and size of PHB granules and in PHB content was observed. The highest PHB levels (2.3 +/- 0.8 mg g-1 dry wt) were recorded in the early morning and the values decreased thereafter with a minimum at night (1.6 +/- 0.9 mg g-1 dry wt). Our data suggest that PHB is a prominent cell constituent in T. thiebautii and that its synthesis takes place in the early morning whereas it is utilized during the rest of the day.

Cyanobacteria↗
PubMed1992

High efficiency presentation of TNP-conjugated islet antigen to islet-specific T cells by a hybrid B cell line expressing TNP-specific surface Ig.

There is compelling evidence from animal models that type I diabetes is a consequence of T cell-mediated destruction of islet beta-cells. The recent isolation of islet-specific T cell clones from nonobese diabetic mice provides a means of identification of the Ag on islet cells that are responsible for stimulation of autoreactive T cells. We describe an APC line constructed by fusion of spleen B cells obtained from nonobese diabetic mice to a B lymphoma that was transfected with the H and L chains of an IgM specific to the hapten TNP. Using this hybrid APC we have observed a dramatic increase in the efficiency of presentation of TNP-conjugated islet cell protein preparations compared to that seen with conventional APC. Our results illustrate the potential use of this APC line for isolation and characterization of islet Ag relevant to the T cell response.

Adenoma, Islet Cell↗
PubMed1992

Vision and visual disability in the daily life of a representative population sample aged 82 years.

A representative population sample (n = 203) aged 82 years was studied to determine the prevalence of impaired vision and visual disability in a cohort previously investigated at the age of 70 years. Visual impairments and disabilities were generally most marked among the non-ambulatory subjects. In the ambulatory group (n = 160) 54% had VA greater than 0.8 and 8% VA less than 0.3. Near vision was also markedly better in this group. About 90% of the ambulatory cases could read J2 or better, read books and watch TV. Statistical analysis showed no sex difference with respect to visual ability for ambulatory subjects. Subjects with a wide range of distance VA were able to read J1 and J2, whereas only one ambulatory patient with J4 or worse had a distance VA above 0.3. To watch TV and manage most of the everyday activities a distance VA of 0.4-0.5 was required. To read newspapers and books a near vision of J2 was needed and for the telephone book J1 was needed. Improvements of near vision obtained by a change of own glasses were small. Hobby and household work proved less dependent on vision. The subjects showed a fairly realistic view of their visual capability, and distance VA was a valuable predictor of visual ability and disability.

Aged↗
PubMed1992

Glutamine synthetase and nitrogen cycling in colonies of the marine diazotrophic cyanobacteria Trichodesmium spp.

We examined freshly collected samples of the colonial planktonic cyanobacterium Trichodesmium thiebautii to determine the pathways of recently fixed N within and among trichomes. High concentrations of glutamate and glutamine were found in colonies. Glutamate and glutamine uptake rates and concentrations in cells were low in the early morning and increased in the late morning to reach maxima near midday; then uptake and concentration again fell to low values. This pattern followed that previously observed for T. thiebautii nitrogenase activity. Our results suggest that recently fixed nitrogen is incorporated into glutamine in the N2-fixing trichomes and may be passed as glutamate to non-N2-fixing trichomes. The high transport rates and concentrations of glutamate may explain the previously observed absence of appreciable uptake of NH4+, NO3-, or urea by Trichodesmium spp. Immunolocalization, Western blots (immunoblots), and enzymatic assays indicated that glutamine synthetase (GS) was present in all cells during both day and night. GS appeared to be primarily contained in cells of T. thiebautii rather than in associated bacteria or cyanobacteria. Double immunolabeling showed that cells with nitrogenase (Fe protein) contained levels of the GS protein that were twofold higher than those in cells with little or no nitrogenase. GS activity and the uptake of glutamine and glutamate dramatically decreased in the presence of the GS inhibitor methionine sulfoximine. Since no glutamate dehydrogenase activity was detected in this species, GS appears to be the primary enzyme responsible for NH3 incorporation.

Animals↗
PubMed1992

Coexpression of ganglioside antigen Fuc-GM1, neural-cell adhesion molecule, carcinoembryonic antigen, and carbohydrate tumor-associated antigen CA 50 in lung cancer.

With the aid of specific monoclonal antibodies, tumor tissues from 68 patients with lung cancer were examined for their expression of two small cell lung carcinoma (SCLC) antigens, Fuc-GM1 (fucosyl GM1; IV2FucII3NeuAc GgOse4) and neural-cell adhesion molecule (NCAM), and two broader tumor antigens, carcinoembryonic antigen (CEA) and carbohydrate cancer-associated antigen CA 50. Expression of Fuc-GM1 was seen in 75% and NCAM in 78% of the SCLC specimens, but also in 12 and 20% of non-SCLC. Either or both of these antigens were expressed in more than 90% of SCLC and in 25% of non-SCLC. CEA was found in more than 80% of SCLC and non-SCLC. Expression of CA 50 was seen in 65-68% of non-SCLC and SCLC, showing preference for SCLC and lung adenocarcinoma. In SCLC, cellular expression of Fuc-GM1 was generally seen together with NCAM and CA 50, but rarely with CEA. There was considerable inter- and intratumor heterogeneity in the expression of all four antigens. The results suggest that CEA is the antigen of choice for the detection of lung cancer regardless of histotype. In combined analysis of CEA, CA 50, Fuc-GM1 and NCAM, two patterns of antigen expression were recognized that appear to discriminate between SCLC and non-SCLC tumors, respectively. A considerable fraction of SCLC and non-SCLC tumors, however, exhibited similar patterns of antigen expression. The biological and clinical significance of these observations remains to be investigated.

Antibodies, Monoclonal↗
PubMed1992

Quality of life during chemotherapy for small cell lung cancer. II. A longitudinal study of the EORTC Core Quality of Life Questionnaire and comparison with the Sickness Impact Profile.

Sixty-two patients with small cell lung cancer, 36-80 years of age, who were receiving chemotherapy during a maximum of one year, were consecutively included in a study of quality of life during treatment. An interim version (C-36) of the EORTC Core Quality of Life Questionnaire (QLQ) was applied for quality of life assessment prior to treatment and every third month during the treatment period. The assessments were related to clinical variables (performance status and tumour response), and compared with results from assessment with the Sickness Impact Profile (SIP). The QLQ was sensitive to differences in clinical status and responded to clinical change over time. In general, the pattern of correlations with SIP lends support to the construct validity of the QLQ. However, some questions arose from the comparison with SIP: QLQ emotional functioning did not change in concordance with SIP, and assessment of social functioning was not optimal prior to treatment. The questionnaire was well accepted by the patients. The EORTC QLQ C-36 constitutes a promising step in the development of a feasible standard instrument for quality of life assessment in cancer clinical trials.

Aged↗
PubMed1992

Base plate wax, dimensional stability and sorption of active components following treatment with disinfectant solutions.

The influence of seven disinfectants on the dimensional stability of a base plate wax, Tenax, was studied. Two methods for treatment were tested - immersion for one hour and spraying respectively. After spraying no significant influence on the wax could be established and after immersion four of the seven disinfectants, including Cidex and K-644, likewise had no significant influence on the dimensional stability. The wax specimens did not show any significant weight increase (less than one per cent) after immersion for four days but in four disinfectant solutions the surface properties of the wax specimens had changed showing that active components of the disinfectants were absorbed into or adsorbed on the wax surface.

Absorption↗
PubMed1991

Cisapride in the treatment of post-operative ileus.

The effect of cisapride on duration of post-operative ileus after surgery was investigated in a randomized, double-blind, placebo-controlled study. Patients undergoing elective upper gastrointestinal (n = 47) or colonic (n = 22) surgery were pre-operatively randomly allocated to treatment with either cisapride 30 mg t.d.s., by rectal administration, or placebo. Treatment started exactly 48 h after surgery if the patient at this time had not passed stool. Time to passage of first stool after surgery was estimated. Mean time to passage of stool was 85 (32) h (s.d.) for cisapride-treated and 91 (43) h for placebo-treated patients. No difference between the treatment groups was noted. Treatment with cisapride did not shorten the duration of postoperative ileus after either upper gastrointestinal or colonic surgery.

Aged↗
PubMed1991

Suicide attempts by battered wives.

During an 8-month period a total of 117 battered wives, all seeking emergency surgical care, were identified. Twenty-two of the battered wives were found to have made 82 suicide attempts during the 16-year study period. This corresponds to an incidence more than 8 times that of an unselected population of women being treated because of attempted suicide in the same hospital. The suicide attempts were predominately passive methods. Although conflict with the husband was the most common triggering factor for the attempt, mental disorder of the woman was another main cause. It is concluded that the doctor, when confronted with a patient who has attempted suicide, always should consider the possibility of ongoing physical abuse. Although battering generally is not the only explanation, the physician should remember this possibility and the patient should, if necessary, be referred to proper care services.

Adolescent↗
PubMed1991

Immunohistochemical detection of two small cell lung carcinoma-associated antigens defined by MAbs F12 and 123C3 in bronchoscopy biopsy tissues.

We have studied MAbs* for their ability to detect SCLC and differentiate this tumor type from the other lung tumor histotypes in cryostat sections of biopsy specimens taken at bronchoscopy from patients with suspected primary lung tumor disease. MAb F12, specific for the ganglioside fucosyl-GM1, reacted with 58% of the cases with SCLC (n = 19) and with less than 3% of those with non-SCLC (n = 38). MAb 123C3, specifically reactive with NCAM, reacted with 78% of the SCLC cases (n = 23). With this MAb no positive staining was seen in the non-SCLC cases (n = 41). None of the two MAbs reacted with tissue sections without tumor. In combined analysis with MAbs F12 and 123C3, all SCLC cases (n = 15) were positive with either and 47% with both of the MAbs. Our results show that both MAbs F12 and 123C3 are highly specific for SCLC in bronchoscopic biopsy tissue specimens, whereas the sensitivity for this histotype tends to be higher with MAb 123C3 than with F12 (P = 0.14). When used in combination, all SCLC cases could be identified. These MAbs may therefore be valuable as complements to current histopathologic characterization and differentiation of lung cancer.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1991

Immunocytochemical localization of nitrogenase in bacteria symbiotically associated with Azolla spp.

In situ immunogold labeling and transmission electron microscopy were used to detect nitrogenase in bacteria (bactobionts) symbiotically associated with leaf cavities of Azolla caroliniana and Azolla filiculoides. In A. caroliniana, the Fe protein of the nitrogenase complex was detected in a subset of the distinct bactobiont types present in leaf cavities of all ages. Similar results were obtained for the bactobionts of A. filiculoides with antisera against both the Fe and MoFe subunits of nitrogenase.

Bacteria↗
PubMed1991

Risk evaluation in a small series of transabdominal chorionic villus sampling.

Previous reports have suggested that the fetal loss rate with transcervical chorionic villus sampling was high in the initial 100-300 procedures performed. In a consecutive series of 155 patients with first-trimester transabdominal chorionic villus sampling (CVS), we observed a total fetal loss rate of 8.4%, and loss rate not attributable to induced abortion or cytogenetic abnormality of 3.2%. Our results demonstrate that transabdominal CVS in the first trimester of pregnancy is a safe method of prenatal diagnosis.

Abdomen↗
PubMed1991

Advantage or disadvantage of episiotomy compared with spontaneous perineal laceration.

In a prospective clinical investigation of 2,144 deliveries, we elucidate the indications for episiotomy and how different methods of anesthesia affect the frequency of episiotomy and the perineal problems after episiotomy compared with those after spontaneous perineal laceration. We found a significantly higher infection rate (p less than 0.001) and a longer healing period in the episiotomy group. These differences remain even if only primigravida or the indication, imminent perineal laceration, is studied. The results indicate that many women will unnecessarily suffer after an episiotomy. The patient's subjective problems are significantly increased, both immediately and at the 3-month postoperative follow-up.

Adult↗
PubMed1991

Teniposide and etoposide in previously untreated small-cell lung cancer: a randomized study.

A randomized study comparing teniposide (VM-26) and etoposide (VP-16) was performed to investigate whether there are any differences in the activity and toxicity of these two analogs in small-cell lung cancer (SCLC). Only previously untreated patients with SCLC were included; 46 and 48 patients receiving VP-16 and VM-26, respectively, are assessable for response. There were no differences between the two groups with respect to extent of disease, median age, and performance status (PS). The initial doses were for both compounds 70 mg/m2 intravenously (IV) daily for 5 days every 3 weeks. After inclusion of 25 patients in the study, the doses were increased to 80 mg/m2 for VM-26 and 90 mg/m2 for VP-16 because of differences in toxicity. VM-26 caused more hematologic toxicity than VP-16 throughout the study. The overall responses (complete response [CR] plus partial response [PR]) were 65% for VP-16 and 71% for VM-26, with CR occurring in 24% and 23%, respectively, for the two compounds. Median survival was 8.5 months for VP-16-treated patients versus 11.3 months for VM-26-treated patients (P = .58). It is concluded that both VP-16 and VM-26 are highly active single agents in SCLC.

Aged↗