In Vitro Target Cell Lysis Mediated by Normal Human Lymphocytes (K Cells) or Monocytes

Guinea pig IgG1 or IgG2 anti-dinitrophenyl (DNP) Antibody preparations were used for induction of target cell lysis by normal human lymphocytes (K cells) or monocytes. Target cells were DNP-coated 51Cr-labeled chicken erythrocytes. Antibody concentrations were assayed by an ammonium sulphate precipitation technique. When antiserum was obtained by immunization with the antigen in Freund's complete adjuvant (FCA), IgG2 antibodies predominated and were significantly more efficient inducers of K-cell-mediated lysis than IgG1 antibodies. The lowest activity in K-cell-mediated lysis was seen with IgG1 from antiserum obtained by immunization with antigen in Freund's incomplete adjuvant. When these antibody fractions were tested in monocyte-mediated erythrolysis, the two IgG1 fractions were as active as the IgG2 antibodies raised with antigen incorporated in FCA. The results suggest that the Fc receptors of mature human blood monocytes are different from those on the effector cells in the K-cell preparations.     

Effects of some calcium antagonists on aggregation by adrenalin and serotonin and on α-adrenoceptor radioligand binding in human platelets

The inhibitory effects of verapamil, nifedipine and diltiazem, representatives of different classes of calcium antagonists, were studied on aggregation of human platelets induced by adrenalin and serotonin (5-HT). For references, the α-adrenoceptor-antagonists phentolamine (α₁ and α₂) and rauwolscine (α₂), and the s-HT₂-receptor-antagonist ketanserin were included. Verapamil in the concentration range 10^-6- 10^-4 M inhibited both adrenalin- and serotonin-induced aggregation in a concentration-dependent manner, whereas nifedipine and diltiazem had little or no effect. Phentolamine and rauwolscine were clearly weaker than verapamil as antagonists of serotonin, and ketanserin lacked effect on adrenalin-induced aggregation. Binding studies with [³H]dihydro-α-ergocryptine and [³H]rauwolscine on human platelet membranes showed equal numbers of binding sites, suggesting that only α₂-adrenoceptors were present. In the same concentration range as inhibition of aggregation was obtained, verapamil inhibited binding of either radioligand. Nifedipine, diltiazem and 5-HT were all poor inhibitors of radioligand binding. The results suggest that verapamil at high concentrations not only has α-adrenoceptor antagonistic properties but also exerts 5-HT-receptor blocking effects. This was not found with the other calcium channel blockers examined (nifedipine, diltiazem).     

Development of a Model System for Analysing Graft-versus-Host-Mediated Immune Suppression

F1 hybrid mice injected with parental T lymphocytes undergo a graft-versus-host (GvH) reaction, one of the consequences being a highly depressed cytotoxic T-lymphocyte (CTL) potential against alloantigens and modified self antigens. In the present study we demonstrate that concanavalin A (Con A) can be used for analysing such GvH-mediated immune suppression. Thus, both alloantigen- and Con A-induced responses were reduced by approximately 80% in F1 suppressed (F1s) animals as compared to F1 control (F1c) mice. Although interleukin 2 (IL-2) production was found to be reduced by approximately 50% it did not account for the reduced CTL response in F1s mice. The addition of IL-2 to Con A-stimulated F1s spleen cell cultures did not reconstitute the response. The results suggest that the suppressive mechanism operates by preventing a large fraction of Lyt-2+ CTL precursors from acquiring IL-2 reactivity. However, a small fraction of CTL precursors, escaped the suppression and differentiated into effector CTL.     

Dyspnoea in a cross-sectional and a longitudinal study of middle-aged men: The Study of Men Born in 1913 and 1923

In a longitudinal population study, 855 men, born in 1913 andinitially examined when 50 years old, were followed for 17 yearswith measurements of dyspnoea and other variables performedat ages 50, 54, and 67 years. In addition a sample of 226 menborn in 1923 was followed from 50 to 57 years of age. At thelatest examination, four different methods for measuring dyspnoeawere used, one based on questionnaire, one on interview, andtwo on visual analogue scales. The estimates from these methodswere highly intercorrelated, and correlated with measures ofcardiopulmonary function as well. The prevalence of dyspnoeagrade 2 (shortness of breath when walking with someone of thesame age on the level) or more, not counting the mildest formof dyspnoea in these populations, was 2.8%, 3.0%, 5.2% and 10.3%at 50, 54, 57 and 67 years of age, respectively. Dyspnoea gradel (shortness of breath when walking quickly on the level oruphill) was less well related to age. A scoring system to differentiatevarious possible causes of dyspnoea was applied. About one thirdof the dyspnoeic men had signs and symptoms of cardiac disease,one quarter had pulmonary disease, and a quarter had a combinationof both causes. The remaining 20% had no signs or symptoms indicatingcardiopulmonary disease but in the majority of the cases otherplausible causes were found.     

Left ventricular function before and after kidney transplantation. A prospective study in patients with juvenile-onset diabetes mellitus

The aim of the present investigation was to discover whetherdisturbed left ventricular (LV) function limits renal replacementtherapy in patients with juvenile onset diabetes mellitus. Seventeenpatients given functioning kidney grafts were studied non-invasively(M-mode echocardiography, apexcardiography, phonocardiography)before renal transplant and an average of six, 13 and 44 monthsafter transplant. The main pretransplant findings were pronouncedLV hypertrophy with impaired diastolic LV function (prolongedrelaxation time + signs of decreased LV distensibility) anda hyperdynamic circulation. Most of these abnormalities were significantly less severe aftersuccessful kidney transplantation. LV mass decreased by 37%44 months after transplant (p<0.01) and LV diastolic andsystolic volumes decreased with a subsequent increase in ejectionfraction from 0.65 to 0.78 (p<0.01). The LV distensibilityand filling pattern improved significantly while the prolongedrelaxation time was unchanged. These findings imply that pretransplant disturbances in LV functionare related more to factors such as hypertension, volume overloadand uraemia than to diabetes per se because no pronounced improvementin the metabolic disorder resulting from diabetes can be expected,even after the most successful transplant. Disturbed LV functionshould not, therefore, exclude uraemic diabetics from renalreplacement.     

INFLUENCE OF FLUID REGIMENS ON PERIOPERATIVE BLOOD-GLUCOSE CONCENTRATIONS IN NEONATES

Blood concentrations of glucose were measured during surgeryand during the first 8 h after operation in 30 neonates undergoingmajor surgery during the first week of life. Fifteen of theneonates were given Ringer-acetate as the only crystalloid peroperativefluid; to the other 15, 10% glucose i.v. was administered duringsurgery, In the Ringer-acetate group, mean (SD) blood concentrationof glucose increased from 3.1 (2.0) to 4.3 (2.4) mmol litre^–1duringsurgery. The corresponding increase in the glucose-supplementedgroup was 3.4 (1.5) to 6.3 (2.2) mmol litre^–1. In theRinger-acetate group, peroperative blood concentrations of glucosewere found to be low if a preoperative glucose infusion wasinterrupted at the start of anaesthesia. Hypoglycaemia occurredin both groups, but more often in the group given Ringer-acetateonly (3/15 vs 1/15). Hypogly-caemia was found only in neonatesless than 48 h of age and during the first 1 h of anaesthesiaonly. Monitoring of blood concentrations of glucose and adjustmentof the glucose infusion appears to be desirable during and aftersurgery in neonates.     

Changes of nursing organization in a surgical department: effects on work satisfaction and quality of care

• ? The aim of the study was to evaluate the effects of an organizational change programme in a surgical department in Sweden (the introduction of modular nursing) on the nursing staffs perception of job satisfaction and quality of care, and to identify factors which promote or hinder this organizational change.
• ? Planning and implementation of the change programme took about 1 year and comprised structural changes and staff training.
• ? Assessments of job satisfaction and quality of care were made immediately before, and 1 year after, implementation of the change programme. Data were collected from the staff of two wards.
• ? Virtually no statistically significant changes were found when looking at the department as a whole. However, considerable differences were noted between the two wards, particularly in the following areas: relationships with colleagues, identification and commitment, and perceived quality of care.
• ? The quality of the interpersonal relationships, and the leadership of the wards' head nurses, appeared to be crucial determinants of the outcome.