Plaque-forming cell capability in the senescent

The number of plaque-forming cells (PFC) developed in pokeweed mitogen (PWM)-activated unfractionated or T/B separated, 4:1 reconstituted cultures of peripheral blood lymphocytes (PBL) with well-characterized subpopulations obtained from healthy, aged subjects was compared to that of young blood donors. The absolute number of PBL in the aged was reduced by 36%, and the percentage of sheep erythrocyte-rosette-forming cells (E-RFC) by 27%, compared to the percentage obtained in young donors. The IgM-, IgG- and IgA-immunoglobulin (Ig) secretion was monitored with a protein A PFC assay. The number of PFC in PBL cultures of the aged was 58% of the number found in cultures of the young controls. The number of PFC generated in cultures of autologous irradiated T and untreated B cells showed a 104% increase in the aged whereas a 63% increase was obtained using cells from young individuals. Co-cultures of young B cells with untreated or irradiated young or aged T cells showed a significant rise in the PFC response in cultures with irradiated aged T cells, while an equal number of PFC was generated in cultures of young B cells with young or aged untreated T cells. Our results demonstrate a decreased number of PBL, especially T cells, an impaired B cell function and a pronounced enhancement of the PFC response in cultures of irradiated aged T cells and young or aged B cells, whereas the T helper function of untreated cells was found to be normal. The influence of monocytes on the PFC response did not differ in the two groups.     

Quantitative assessment of psychologic state of patients with anorexia nervosa or bulimia: response to caloric stimulus

Hospitalized patients with anorexia nervosa (N = 17) or bulimia (N = 11) were given a standard liquid meal containing 400 calories. Using analogue scales, bulimic patients were found to have greater anxiety, lower mood, lower sexual arousal, and more fear of fatness than either control or anorectic patients. This finding of increased general "dysphoria" in bulimic patients persisted after the meal without any significant premeal to postmeal changes. Anorectic patients also differed from controls, but less than the bulimic patients. Some measures of anxiety correlated significantly with body mass index before the meal in bulimic patients, whereas in anorectic patients the correlation was significant only after the meal.     

Neonatal outcome in a Danish national cohort of 3438 IVF/ICSI and 10,362 non-IVF/ICSI twins born between 1995 and 2000

BACKGROUND: In Denmark, one-third of twin pregnancies are the result of IVF/ICSI treatment. Limited data on neonatal outcome in IVF/ICSI twins are available in the literature. METHODS: A register study was conducted on neonatal morbidity and mortality in a complete national twin cohort including all 3438 (3393 live-born) IVF/ICSI and 10,362 (10,239 live-born) non-IVF/ICSI twins born between 1995 and 2000. Twins were identified in the National Medical Birth Registry and dichotomized into IVF/ICSI and non-IVF/ICSI by cross-reference with the Danish IVF Registry. Data on neonatal morbidity and mortality were retrieved from the Danish Patient Registry and the Danish Registry of Causes of Deaths. In order to exclude monozygotic twins, sub-analyses on unlike-sex twins were conducted. RESULTS: A birth weight discordance of >20% was observed in 20.6% of IVF/ICSI versus 15.7% of control twin pairs (P < 0.001). The risk of discordant birth weight >20% was OR 1.29 (95% CI 1.04-1.58) in unlike-sex IVF/ICSI twins versus control twins. The risk of delivery at <37 completed weeks and birth weight <2500 g was similar in the two cohorts; however, in unlike-sex IVF/ICSI versus control twins the risk of delivery at <37 weeks and birth weight <2500 g was OR 1.22 (95% CI 1.09-1.38) and OR 1.25 (1.11-1.40) respectively. After stratification for maternal age and parity, these risks disappeared. IVF/ICSI twins carried a higher risk of admittance to a neonatal intensive care unit (NICU) than control twins (OR 1.18, 95% CI 1.09-1.27), and this was even more pronounced in unlike-sex twins [OR 1.34 (95% CI 1.19-1.51)]. No differences were observed in malformation or mortality rates between the two cohorts. CONCLUSIONS: Despite higher birth weight discordance and more NICU admissions among IVF/ICSI twins, neonatal outcome in IVF/ICSI twins seems to be comparable with that of non-IVF/ICSI twins, when only dizygotic twins were considered in the comparisons.     

Doctors'' characteristics do not predict long-term glycaemic control in type 2 diabetic patients.

Glycaemic control in type 2 diabetic patients varies widely between general practitioners (GPs). To increase our understanding of this variation, linear random effects models were used to examine the predictive value of GP characteristics on the course of annual HbA1c measurements, in 688 newly diagnosed type 2 diabetic patients between one and five years after diabetes diagnosis. We found that characteristics of centrally supported GPs, such as interest in diabetes, experience, practice type, list size, and weekly working hours, did not predict their patients' glycaemic control.     

High-throughput single strand conformation polymorphism mutation detection by automated capillary array electrophoresis: validation of the method

Capillary array electrophoresis (CAE) is a novel technique, which allows for high throughput analysis of DNA fragments. When screening for mutations in whole populations or large patient groups it is necessary to have robust and well-characterized setups for high throughput analysis. For large-scale mutation screening, we have developed procedures for single strand conformation polymorphism (SSCP) assays using CAE (CAE-SSCP) whereby we may increase both the sensitivity and the throughput compared to conventional SSCP analysis. In this study we have validated CAE-SSCP by 1) comparing detection by slab-gel based SSCP with CAE-SSCP of mutations in the MYH7, MYL2, and MYL3 genes encoding sarcomere proteins from patients suffering from hypertrophic cardiomyopathy; and 2) by constructing a series of 185 mutants having substitution mutations, as well as insertion/deletion mutations, or some combinations of these, in different sequence contexts in four exons and different positions relative to the end of the amplicon (three from the KCNQ1 gene, encoding a cardiac potassium channel, and one from the TNNI3 gene encoding cardiac troponin I). The method identified 181 out of 185 mutations (98%), and the data suggest that the position of mutation in the fragment had no effect on the sensitivity. Analysis of the specificity of the method showed that only very few mutants could not be distinguished from each other and there were no false positives.     

Hydrochlorothiazide and potassium chloride in comparison with hydrochlorothiazide and amiloride in the treatment of mild hypertension

A randomized, double-blind, cross-over study comparing 50 mg hydrochlorothiazide plus 5 mg amiloride (HCTZ/A) with 50 mg hydrochlorothiazide plus 26 mmol potassium chloride (HCTZ/K) was conducted in 18 patients with mild essential hypertension (diastolic pressure 90-105 mmHg). The sequence of treatment was: placebo for 2 weeks, one active drug for 3 weeks, placebo for 2 weeks, the other active drug for 3 weeks. The two agents were significantly and equally efficacious in lowering the systolic and diastolic blood pressure. Baseline vs. treatment mean serum potassium levels were 3.82 vs. 3.78 mmol/l for HCTZ/A and 3.82 vs. 3.70 mmol/l for HCTZ/K. The decrease in serum potassium level from baseline was significant for both agents but not significantly different when the two treatment forms were compared. Both treatment forms elevated fasting serum cholesterol and glucose. Serum triglycerides and uric acid rose significantly with HCTZ/K. Amiloride may affect the tubular handling of uric acid causing increased uric acid excretion, thus counteracting thiazide-induced hyperuricemia. During 3 weeks' extension of the main study, 5 patients received HCTZ/A in double the original dose (100 mg/10 mg) and 6 patients received HCTZ/K in double the original dose (100 mg/52 mmol). No further blood pressure reduction was observed on treatment with these doses. The mean serum potassium levels did not decrease further on doubling the HCTZ/A dose, while a significant fall was observed for HCTZ/K (3.60 vs. 3.42 mmol/l) (p less than 0.05, single tailed t-test). Both drug combinations were well tolerated and side-effects were not significantly different from those during placebo administration. This study demonstrates that 50 mg hydrochlorothiazide plus 26 mmol potassium chloride are as effective as 50 mg hydrochlorothiazide plus 5 mg amiloride, both in reducing blood pressure and preventing hypokalaemia in the treatment of essential hypertension. A small extension study indicates that amiloride might be more effective than potassium chloride in preventing hypokalaemia when high doses (100 mg/day) of hydrochlorothiazide are administered.     

The level of the serum opsonin, mannan-binding protein in HIV-1 antibody-positive patients.

The concentrations of mannan-binding protein (MBP) in consecutive samples from 10 HIV+ persons were estimated using an ELISA based on polyclonal rabbit anti-MBP. The changes in MBP with time were similar in HIV+ and HIV- persons, and did not appear to be of clinical significance. MBP was determined in a further 70 persons found HIV-1+ during a period of 2.5 years (1984-1986). Out of the total of 80 patients, 32 have by now died from AIDS. According to the serum level of MBP the HIV-infected persons were grouped into high (> 650 ng MBP/ml), intermediate (101-650 ng/ml), and low MBP (< 101 ng/ml). At the termination of the study the frequency of deaths/total in each of the groups were: high MBP, 14/39 (36%); intermediate MBP, 12/26 (46%); and low MBP, 6/14 (43%). There was no association between the MBP level of the individual and the progressive loss of CD4+ T cells, and the level of MBP was not predictive for the length of time between the detection of HIV antibodies and development of AIDS, nor for the duration of AIDS before death occurred. The number of HIV+ persons without detectable MBP (10%) was significantly higher than previously reported for healthy persons (2.4%, P = 0.027). The course of HIV infection does not seem to be influenced by the level of MBP, nor does the antimicrobial activity of MBP appear to affect the progression of AIDS. Further studies are required to substantiate the significance of absence of MBP in the susceptibility to HIV.     

Effect of sodium ions on penicillin-induced epileptiform activity in vitro

Summary Intra- and extracellular recordings were obtained from the CA1 region of guinea pig hippocampal slices maintained in vitro. We studied the effect of reducing the extracellular sodium concentration on penicillin-induced epileptiform responses.In control experiments, Tris and choline were assayed as sodium substitutes. Choline was found unsuitable, since it induced repetitive firing in the absence of any convulsant agent. Replacement of 50% of the extracellular sodium ([Na⁺]_o) with Tris reduced the amplitude of the presynaptic fiber volley, the field EPSP, and the population spike. Intracellular studies showed that when [Na⁺]_o was lowered, action-potential amplitudes were reversibly depressed by an amount close to that predicted by the Nernst relation.Orthodromically elicited epileptiform discharges, induced by penicillin, were reduced in a low-sodium medium when constant stimulus currents were employed. If orthodromic stimulus strengths in normal and low-sodium states were equated on the basis of the field-EPSP amplitude, no significant diminution of the depolarizing-wave component of the epileptiform response was observed. These results suggest that a synaptic component underlies penicillin-induced epileptiform discharges.Supported by grants from the Norwegian Research Council for Science and the Humanities and by NIH grants NS 11535 and NS 15772     

IgG antibodies to purified Aspergillus fumigatus antigens determined by enzyme-linked immunosorbent assay

IgG antibodies to three purified Aspergillus fumigatus antigens were determined by enzyme-linked immunosorbent assay (ELISA) in sera from 26 patients with definite pulmonary aspergillosis (group 1), 23 patients with suspected pulmonary aspergillosis (group 2), 8 patients with precipitating antibodies to A. fumigatus of undetermined clinical significance (group 3), and 113 healthy blood donors (group 4). With a 470,000-dalton antigen fraction ELISA values exceeded the upper range of group 4 (0.72) in 92, 91 and 13% of cases in groups 1, 2 and 3, respectively. With a 250,000-dalton antigen fraction the figures were 96, 78 and 13%, respectively (upper range of group 4 = 0.25). With an antigen fraction of 25,000-50,000 daltons the figures were 96, 65 and 13%, respectively (upper range of group 4 = 0.18). In 48 of 49 cases of definite or suspected aspergillosis (groups 1 + 2) ELISA values with at least one antigen exceeded the upper range of controls (group 4). It appears that antibody determination with these three antigen fractions may have a high diagnostic sensitivity.