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Biomedical subjects

M Klein

Publications and source records attributed to M Klein.

At least 631 records · Page 35Linked to original sources
PubMed1983

Early clinical diagnosis of the syndrome of inappropriate secretion of antidiuretic hormone. Case reports.

Two children with inappropriate antidiuretic hormone secretion associated with meningococcal septicaemia are described. The syndrome was diagnosed despite the patients' serum sodium concentrations being within the normal range when, with normal fluid intake and in the absence of hypovolaemia, they developed oliguria and concentrated urine. Early diagnosis prevents cerebral water intoxication and pulmonary oedema that may occur if hyponatraemia is allowed to develop.

Child, Preschool↗
PubMed1983

Comparative investigations on the effect of the phase-specific drug vincristine (VCR) on the proliferation kinetics of a solid experimental tumor.

The aim of the present investigation was to compare the effects of repeated and single applications of vincristine (VCR) to a solid tumor in mice during the phase of tumor growth retardation 14 days after transplantation. Furthermore an attempt was made to induce synchronized tumor cell proliferation. Retardation of volume growth was found to be very much more pronounced after repeated application of VCR than after a single dose of this cytostatic drug. The intensity of the effect decreased within the tumor itself from the periphery to the centre. A synchronization of tumor cell proliferation by flow out from the mitotic block or by a high simultaneous recruitment of previously noncycling tumor cells into the cell cycle could not be demonstrated.

Animals↗
PubMed1983

[Ambulatory medical care of the over-65 patient].

Based upon two investigations involving a sample of the elderly in Basle and Berne and a sample of physicians in private practice throughout the country, a description of the ambulatory health care of the population of Switzerland aged 65 and over is presented. Significant results include the role of the family physician, home visits, the kind of therapy and follow-up as well as the remarkable finding that the utilization of the family physicians' services is influenced by the presence of health insurance coverage. (34% of the people aged 85 and over are without coverage).

Aged↗
PubMed1983

Immunological markers of human mononuclear cells.

The immune response to an antigenic challenge results from complex intercellular communications between several populations of lymphoreticular cells. Immunocompetent cells are derived from a common stem cell precursor and develop along two distinct pathways. The T-cell lineage (T-lymphocytes) originates in the thymus and mediates cellular immunity, whereas B-cells (bone marrow derived lymphocytes) mature into antibody producing cells. The maturation of B-cells into plasmacytes is under the control of two regulatory T-cell subsets. Helper T-cells (TH) induce the differentiation of B-cells into antibody producing cells. In contrast, suppressor T-cells (TS) inhibit this maturation process. Therefore, immunoregulation results from a delicate balance between inducer and suppressor T-cell subsets. The various lymphocyte populations and subsets express specific membrane glycoproteins (surface antigens and receptors) which therefore allow their identification by cell surface marker analysis. The advent of hybridoma antibodies directed against unique integral membrane proteins has provided a powerful tool for characterizing lymphocyte subsets and for understanding the antigenic changes that occur during their ontogeny. Pre-B cells produce intracytoplasmic mu chains. B cells express surface immunoglobulins, Ia antigens, Fc receptors and complement receptors. Plasmacytes contain intracytoplasmic immunoglobulins. T-cells form spontaneous rosettes with sheep erythrocytes. Helper T-cells express a specific surface antigen (T4), whereas cytotoxic/suppressor T-cells bear another membrane marker (T8). The use of such immunological markers has greatly facilitated the dissection of various human diseases, such as lymphoproliferative malignancies, autoimmune disorders and immunodeficiencies.

Antibody Formation↗
PubMed1983

Rapid methods in studies on the genetic changes induced by chemicals.

Eight new compounds of the quaternary ammonium salts group were investigated for mutagenicity. Tests were carried out on onion roots (Allium test) and on bacteria (Ames' test) to examine the mitosis disturbances. None of the compounds produced mutagenic activity in the bacterial test, whereas in the Allium test two compounds produced a strong effect on mitotic cell division.

Animals↗
PubMed1983

[Methodologic studies on protein metabolism and bioenergetics of protein deposition in growing animals. 4. Energy metabolism in chickens in connection with measurement of parameters of protein metabolism].

In connection with the measuring of parameters of the protein metabolism in parallel experiments, the energy metabolism of 6 chickens (origin Tetra B) in the live weight range between approximately 100 and 1,800 g was determined under conditions of restricted energy supply. 3 animals each received a feed mixture containing 20% (animal group 1) and 38% (animal group 2) crude protein. The amount of feed was daily increased by 1.5 g DM. The digestibility of energy and nitrogen was independent of the age. 66.3 +/- 3.3% and 64.0 +/- 5.0% resp. of the metabolisable energy were utilised for protein and fat retention. The energy maintenance requirement, determined at a live weight of 2,000 g, was independent of protein supply and averaged in the two animal groups 434 +/- 40 kJ metabolisable energy/kg live weight 0.75 . d. The result of multiple regression was, for the growth period investigated, an energy maintenance requirement of 403 +/- 32 kJ metabolisable energy/kg live weight 0.75 . d. 1.77 and 1.38 J metabolisable energy resp. were required for 1 J protein or fat retention. The energy requirement for protein retention was independent of the degree of protein supply. The results from the measuring of energy metabolism are discussed in connection with the kinetic parameters of protein metabolism ascertained in parallel experiments.

Animals↗
PubMed1983

Immunologic responses of children to serious infections with Streptococcus pneumoniae.

Antibody responses (as measured by radioimmunoassay), alterations in serum levels of complement, and the presence of circulating immune complexes (as measured by the fluid-phase C1Q-binding assay, the fluid-phase conglutinin assay, and the activation of C1 were evaluated in 15 children after meningitis and/or bacteremia caused by Streptococcus pneumoniae. The ages of the children ranged from two months to 16 years; the duration of follow-up ranged from 18 to 189 days (mean, 78 days). Increases in levels of homotypic antibody were found in only three (25%) of the 12 children in whom this response could be assessed, and all of these responses were transient. Eight (53%) of the 15 children had evidence of a heterotypic antibody response to S pneumoniae serotypes other than those causing their infections. The activation of C1 and C1q-binding activity were detected at the early stage of disease and were generally transient. The result of the fluid-phase conglutinin assay was positive for 14 (93%) of the 15 children later in the course of disease; this result was consistently positive throughout the follow-up period in the majority of children. Depressed concentrations of C4 were noted in nine children, depressed levels of C3 in four, and depressed levels of factor B in two.

Adolescent↗
PubMed1983

A comparison of low-risk pregnant women booked for delivery in two systems of care: shared-care (consultant) and integrated general practice unit. I. Obstetrical procedures and neonatal outcome.

Samples of records of comparable low-risk pregnant women booked for delivery in an integrated general practice unit (GPU) and a consultant (or shared-care) system were derived from a computer tape of all 5005 births which occurred at the John Radcliffe Hospital in 1978. Induction of labour, epidural analgesia and forceps delivery were all less frequently carried out in women booked for delivery in the GPU. Infants of multiparous women were more often intubated in the shared-care system (3%) than in the GPU (0%); rates in infants of nulliparous women were similar (approx. 7%) in the two systems. These data suggest that short-term outcomes are as good for GPU-booked low-risk women and their infants as for comparable women booked in consultant or shared-care.

Adolescent↗
PubMed1983

A comparison of low-risk pregnant women booked for delivery in two systems of care: shared-care (consultant) and integrated general practice unit. II. Labour and delivery management and neonatal outcome.

A random sample of low-risk pregnant women were equally divided into four groups of 63 nulliparae and multiparae each booked for care in a integrated general practice unit (GPU) and a shared-care (consultant) system. Selection criteria included only women who were admitted because they were in spontaneous labour or thought they were. Nulliparous women booked for shared-care came into hospital at a less advanced state of cervical dilatation than those booked for the GPU and spent longer (11 compared with 8 h) in hospital before delivery; the comparable durations in multiparae were 6 and 4 h. Both the first and second stages of labour were longer in the GPU-booked women but they received less pethidine and fewer had epidural analgesia; they received less electronic fetal monitoring, augmentation and forceps delivery, and fetal distress was diagnosed less often. The 1-min Apgar score was less than or equal to 6 in 17.5% of infants of nulliparae booked for the shared-care system compared with 1.6% of those booked for the GPU. The intubation rate of infants of nulliparae was 11% in the shared-care system compared with no intubations in the GPU. These comparisons demonstrate the simplicity and safety of delivery of low-risk women in the GPU as compared with deliveries of similar women in a shared-care (consultant) unit.

Adolescent↗
PubMed1983

Pulmonary disposition of tobramycin.

Each antibiotic has a characteristic penetration into respiratory secretions, influenced by serum concentration, protein binding, transport systems, and the presence of infection. Whereas previous studies have used only bronchial secretions and blood, in the present study, blood, bronchial secretions, and bronchoalveolar lavage (BAL) fluid were analyzed for tobramycin levels. In 10 studies in 9 patients, serum levels were significantly related to BAL fluid levels (r = 0.8, p less than 0.01) when both were expressed as a function of creatinine (mean BAL level +/- SD = 144 +/- 124 micrograms/mg creatinine; serum level, 293 +/- 216 micrograms/mg creatinine). The level of drug penetration in BAL fluid, expressed by the slope of the relationship between blood and fluid, was 0.5. The penetration of tobramycin into bronchial secretions ranged from 0 to 1.4 micrograms/ml, the ratio of secretions to serum being 0.2 (r = 0.68; p less than 0.05). It is concluded that the disposition of tobramycin in bronchial secretions and BAL fluid differ. Thus, sampling both fluids offers a more suitable method to study antibiotic pharmacokinetics in bronchi and alveoli.

Adult↗
PubMed1983

Delineation of four cell types comprising the giant cell tumor of bone. Expression of Ia and monocyte-macrophage lineage antigens.

Giant cell tumors of bone dissociated by collagenase digestion were found to be composed of four different cell types defined by morphology, growth in culture, and pattern of staining with monoclonal antibodies. Giant cells comprised an average of 0.8% of the cells recovered, with the remainder consisting of small stromal cells. Of the giant cells, 20-57% expressed Ia antigens, while all lacked IgG Fc receptors and five differentiation antigens associated with mature members of the monocyte-macrophage lineage (M phi S-1, M phi P-9, M phi P-15, M phi S-39, and 63d3). One antigen, M phi U-50, found on early monocytoid forms was expressed on Ia+ giant cells. 6-36% of the remaining stromal tumor cells formed a second subpopulation that assumed either a rounded or elongated shape in culture. These cells bore Ia antigens, IgG Fc receptors, and five antigens of the monocyte-macrophage lineage usually found on blood monocytes. However, these cells differed from monocytes or macrophages in that the antigen M phi R-17 generally found on tissue macrophages was absent, and the M phi U-50 antigen present on more primitive cells was well expressed. A very limited endocytic capacity was demonstrable. A third population of up to 24% of the tumor cells was defined by the presence of intense staining for Ia antigens but the absence of antigens of mature monocytes. A proportion of these cells expressed M phi U-50 and a minority had IgG Fc receptors. The two Ia(+) populations of stromal cells were not identifiable after 2 wk of culture, nor did tumor cells selected for the presence of Ia antigens proliferate in culture. A fourth population of cells lacked Ia and monocyte lineage antigens, but showed pronounced intracellular staining for acid phosphatase. These cells had a distinctive plump epitheloid to fibroblastoid morphology and were readily established in long-term culture where they gave rise to large multinuclear Ia(-) cells containing acid phosphatase. The possibility is discussed that the cell types of these tumors relate to various stages in the development of osteoclasts from precursors in the mononuclear phagocyte lineage.

Acid Phosphatase↗
PubMed1983

Characteristics of a benign subtype of dense deposit disease: comparison with the progressive form of this disease.

Pathologic, clinical and serum complement studies were performed on 18 patients with dense deposit disease (DDD). The patients were divided into 3 groups: group A (10 patients who developed end-stage renal failure within 2.9 +/- 1.0 years of onset) group B (3 patients who developed elevated serum creatinines within 6.8 +/- 4.8 years of onset) and group C (5 patients with no evidence of renal insufficiency after 11.0 +/- 1.4 years of follow-up). Renal biopsies from all patients showed intramembranous, electron-dense deposits in glomerular capillary basement membranes. Most group A and B patients presented with a nephritic and/or nephrotic syndrome and followed an active clinical course. In contrast, group C patients presented with either a nephrotic syndrome or asymptomatic proteinuria +/- hematuria and followed a benign course. Sera from group A and B patients contained reduced concentrations of C3 and factor B and large amounts of C3 nephritic factor (NeF) activity. In contrast, serum of group C patients contained normal amounts of C3 and factor B and low levels of C3 NeF activity. These studies show that some patients with DDD (group C) have a benign illness and that they can be identified by serum levels of C3, factor B and C3 NeF activity.

Child↗
PubMed1983

[Comparative survey concerning methods of vestibular exploration used in 10 Western European countries].

For the first time, a survey was conducted in 10 western European countries to compare methods used for vestibular exploration. Statistical analysis of findings showed that apart from spontaneous tests there was a tendency for aqueous, gaseous, rotatory, pendular instrumental tests to be used with increasing frequency, with more widespread application of electronystagmography. Finally, there appears to be marked similarities between and even standardization of the methods used in the different countries.

Europe↗