Enalapril maleate and atenolol combined with hydrochlorothiazide in moderate to severe essential hypertension

This open randomised parallel trial compared the antihypertensive efficacy of enalapril and atenolol given alone once a day or with hydrochlorothiazide in 20 patients with moderate to severe hypertension. Active treatment was over a 26 week period, consisting of an initial titration phase followed by a fixed dose phase. Both treatment regimes effectively lowered systolic and diastolic blood pressures. All patients on enalapril reached normotension (supine diastolic blood pressure less than or equal to 90 mmHg) compared with 78% on atenolol. Pulse rate was not appreciably changed by enalapril, but was significantly reduced by atenolol. No serious adverse reactions or significant changes in laboratory values were noted in either group. The commonest adverse reaction with enalapril was dizziness which occurred in two cases and resolved on dosage reduction. Enalapril with hydrochlorothiazide given once daily may provide a useful combination in the treatment of moderate to severe hypertension.

Class and subclass anti-pneumococcal antibody responses in splenectomized patients

Antibody titres against pneumococcal capsular and cell wall antigens and the immune response to polyvalent pneumococcal vaccine were measured in 21 splenectomized patients and 12 healthy controls. Most individuals possessed anti-pneumococcal capsular polysaccharide antibodies of IgG, IgA and IgM classes. The anti-capsular IgG was predominantly of the IgG1 and IgG2 subclasses; only occasional individuals had any detectable titre in IgG3 or IgG4 subclass. Most individuals responded to immunization with Pneumovax. There was no clear difference between groups of control and splenectomized subjects, although three of the splenectomized patients had undetectable pre-immunization anti-capsular titres in one or more subclass which failed to rise following immunization. All subjects tested had anti-phosphocholine antibodies in IgG, IgA and IgM classes with the exception of a single splenectomized patient who lacked detectable anti-phosphocholine IgM. Pre-immunization titres where similar in healthy controls and splenectomized patients. There was no demonstrable rise in anti-phosphocholine titre following immunization with Pneumovax.

Selective depression of thymus-independent anti-DNP antibody responses induced by adult but not neonatal splenectomy

The effect of splenectomy was assessed on rats' capacity to respond to 2,4-dinitrophenol (DNP) conjugated to spider crab haemocyanin (MSH) or hydroxyethyl starch (HES). The response to DNP-HES was profoundly suppressed in all immunoglobulin classes and subclasses by adult splenectomy. This loss of responsiveness increased with time after removal of the spleen. By contrast no significant effect on the anti-DNP-MSH response was caused by splenectomy. Experiments in congenitally athymic rats confirmed the thymus dependency of anti-DNP antibody responses of all classes and subclasses induced by DNP-MSH. DNP-HES responses, however, were elevated in athymic animals. The effect of adult splenectomy in these animals was considerably less than that produced in euthymic rats. Neonatal splenectomy in euthymic rats only resulted in minor impairment of these rats' capacity to respond to DNP-HES as adults, indicating the ability of rats to compensate after neonatal but not adult splenectomy. These data are taken to show that the spleen plays an important role in responses against this thymus-independent type II antigen which is only partially replaceable by other compartments of the immune system.

The treatment strategies of arthritis sufferers

This paper describes and analyses the reasons for variation in the treatment strategies used by arthritis sufferers. The research was undertaken among 103 people from the Australian city of Perth. Qualitative data was obtained from a clinical sample of 27 and, on the basis of that, an interview schedule was constructed and administered to a survey sample of 76 self-reported arthritis sufferers. Data collected included comprehensive case histories, knowledge and beliefs about arthritis, types of practitioners consulted and treatments used and a range of demographic and socioeconomic variables. On the basis of analysis, four basic treatment strategies were discerned. Named after their most salient characteristics and ranging from least to most inclusive these were 'general practitioner and/or self care', 'medical and paramedical care', 'medical and alternative care' and use of 'all sources of care'. The most important determinants of treatment strategy were characteristics of disease--severity, mode of onset and period since onset. The longer the period since onset, the wider the range of treatments utilized. When onset occurred at a relatively young age and when progression was rapid, the more frequently alternative services and treatments were employed. Disease characteristics were followed in importance by socioeconomic factors. Use of the less inclusive strategies was related to social class; with working class people relying primarily on 'general practitioner and/or self care' and middle class people using 'medical and paramedical care'. However, when onset and progression were rapid, the disease was severe and the person relatively young socioeconomic factors were of lesser importance and people from all classes made use of the more inclusive strategies.(ABSTRACT TRUNCATED AT 250 WORDS)

Relation of intra-splenic migration of marginal zone B cells to antigen localization on follicular dendritic cells

Injection of heat-killed Escherichia coli into rats results in massive loss of IgM + ve, IgD - ve B cells from the marginal zones of their spleen within 4 hr. This is matched by a concomitant increase of cells with this phenotype in the splenic follicles. The marginal zone remains depleted and the follicles distended for about 16 hr, but the histological picture returns to normal within 24 hr. Surface marker analysis of blood and spleen B lymphocyte populations throughout the course of the migration suggest that there is intrasplenic migration of IgM + ve cells from marginal zone to follicles rather than via the circulation. Factors inhibiting localization of immune complex on follicular dendritic cells were assessed for their influence on marginal-zone B cell migration. Immune complex, injected 5 hr post-endotoxin administration localized poorly on follicular dendritic cells. While C3 depletion, by cobra venom, has no effect on marginal-zone B cell migration induced by endotoxin, it completely inhibits transport of heat-aggregated human gammaglobulin to follicular dendritic cells.

Blood volume changes and arginine vasotocin (AVT) blood concentration in conscious fresh water and salt water adapted ducks

Blood volume changes consisting in the removal and reinfusion respectively, of 10% of the estimated blood volume (23.2 ml on average) were induced to determine their effects on the blood concentration of arginine vasotocin (AVT), the antidiuretic hormone (ADH) of birds, in fresh water adapted ducks (water ducks) with blood osmolalities and ADH concentrations similar to those of normally hydrated mammals, and in salt water adapted ducks (salt ducks) with chronically elevated blood osmolalities and ADH concentrations. The investigations were carried out in steady state conditions, when infusion of 1 ml . min-1 of isotonic saline was matched by the excretion in water ducks and when infusion of 0.4 ml . min-1 of 1,000 mosmolal saline was matched by the salt gland excretion in the salt ducks. After blood removal, AVT blood concentration (mean +/- SE) increased from 6.5 +/- 0.4 to 8.4 +/- 0.6 pg . ml-1 in water ducks and from 18.1 +/- 1.6 to 22.6 +/- 1.9 pg . ml-1 in salt ducks. The respective blood osmolalities of 297.4 +/- 1.4 and 318.6 +/- 3.3 mOsm . kg-1 did not change. Reinfusion of the blood after steady-state conditions had been reattained decreased blood AVT from 7.9 +/- 0.7 to 6.7 +/- 0.5 pg . ml-1 in water ducks. In the salt ducks AVT concentration had already returned to the control level before blood reinfusion which induced no further reduction. The blood osmolalities remained unchanged in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Marginal zone B cells express CR1 and CR2 receptors

Opsonized yeast is known to bind strongly to the marginal zones in frozen sections of rat spleen (Kumararatne, D. S. et al., Eur. J. Immunol. 1981. 11: 858). This study reports an analysis of the cells involved in this binding. Sheep red cells coated respectively with C3b, C3bi or C3d were used as indicator cells. These showed homogeneous binding of both C3b and C3bi to marginal zones and germinal centers. C3d-coated red cells bound in a uniform speckled pattern to marginal zones. They also bound to germinal centers and the small lymphocyte zones of the follicles. Selective depletion experiments were undertaken to show that binding to marginal zones was a property of the IgM+ and IgD- B cells characteristic of this area. Binding to germinal centers was attributable to follicular dendritic cells. The C3d receptors in follicles were shown to be on IgM+ and IgD+ small B lymphocytes.

Vasopressin in blood and third ventricle CSF during dehydration, thirst, and hemorrhage

Samples of cerebrospinal fluid (CSF) were collected from the anterior part of the third cerebral ventricle of mongrel dogs with a chronically implanted device. Repeated experiments with simultaneous sampling of CSF and venous blood in 60- to 90-min intervals were performed in conscious dogs after 24-h water deprivation and during subsequent rehydration by drinking, during thirst stimulation by intravenous infusion of 5% saline, and during blood removal (12 ml X kg body wt-1). The CSF and plasma samples were analyzed for osmolality and arginine vasopressin (AVP) with a radioimmunoassay. Compared with normally hydrated dogs, 24-h water deprivation caused plasma AVP to rise significantly from 2.5 to 7.7 pg X ml-1 and CSF AVP from 24.2 to 31.3 pg X ml-1. Subsequent drinking significantly reduced plasma and CSF AVP. Thirst stimulation by hypertonic infusions was associated with rises of plasma and CSF AVP. Modest reduction of blood volume also increased both plasma and CSF AVP. Plasma AVP in each of the described physiological disturbances of salt or fluid balance was positively correlated with CSF AVP.

Vasopressin in blood and third ventricle CSF of dogs in chronic experiments

A device for chronic implantation was developed that allowed sampling of cerebrospinal fluid (CSF) from the anterior part of the third cerebral ventricle (A3V) of dogs in repeated experiments for up to 4 mo. Osmolalities, electrolyte concentrations, and concentrations of arginine vasopressin (AVP) measured with a radioimmunoassay were determined in repeated experiments on the chronically prepared animals under conditions of normal hydration, both in the conscious state and during inhalation anesthesia. In conscious dogs, AVP concentrations in plasma and CSF were 3.3 +/- 0.4 and 21.8 +/- 2.5 pg X ml-1, respectively. During anesthesia without surgical interference, the AVP concentrations in plasma and CSF were increased twofold above the levels obtained in conscious dogs. During the time of observation (180 min) all measured parameters remained constant. The AVP concentrations in plasma and CSF samples collected during the surgical procedure of device implantation were about 10-fold higher than in the samples collected during the conscious state. Thus, in each experimental condition, AVP concentration in the CSF collected from the A3V was consistently higher than that in the simultaneously collected blood samples.

Evidence bearing on the generalizability of laboratory findings relating to high-altitude mountaineering

An evaluation of the psychological effects of high-altitude mountaineering was conducted on three subjects before, during, and after their ascent of a 25,600-ft. mountain. The assessment incorporated a battery of cognitive tests within a single-subject design, and the results indicated the absence of an effect. This is contrary to laboratory findings on the stressors involved in mountaineering, such as hypoxia. These have generally been reported as significantly influencing cognitive functioning.

Percutaneous initiation of cardiopulmonary bypass

Improved technology has allowed us to develop support pumps that can be applied rapidly and safely. A system utilizing thin-walled (4 mm inner diameter) percutaneously inserted sheaths has been designed for rapid bedside arterial and central venous cannulation to establish femoral arterial and venous cardiopulmonary bypass. The system utilizes two 30-cm-long large-bore, thin-walled (end and side holes) venous cannulas and a single 15-cm-long (end hole) arterial reperfusion cannula, which is connected to a pediatric oxygenator and a vortex pump head. Five patients with refractory cardiac arrest who could not be resuscitated by conventional means were revived with this system. Application time was approximately five minutes. This system appears to be an easily applied and reliable short-term mechanical support device.

A job club for older job seekers: an experimental evaluation

Labor market trends and expert opinion have recently highlighted the existence of an "older worker problem" that will require policy and programmatic remedies. This study details the findings of a longitudinal field experiment on the effectiveness of a promising behavioral/self-help job-finding program --the job club. Employment service clients (N = 46) were randomly assigned to receive the job club program or normally available (control) services. Twelve week follow-up data revealed a 74% employment rate for job club participants versus 22% for controls. Both groups obtained comparable placements. Study findings indicate the job club is an effective employment service for older job seekers.

Migrant mu+ delta+ and static mu+ delta- B lymphocyte subsets

Immunoglobulin isotype expression in isolated lymph node (LN), spleen and blood lymphocyte suspensions was assessed in rats. The proportion of mu+ delta- B cells in spleen (34%) was approximately twice that in blood and LN. Immunohistological examination of spleens showed the cells of the marginal zones to be predominantly mu+ delta-. On the other hand, mu+ delta+ B cells were mainly confined to the follicles in both spleen and LN. These follicles had a minor mu+ delta- component. The migratory properties of B cells with these two phenotypes were assessed by depleting lymphocytes migrating through the white pulp of rat spleen. This was achieved by placing a 32P-impregnated beta-emitting polythene strip over one half of the spleen. Examination of the nonirradiated half of the spleen, LN and peripheral blood after 12 days irradiation showed selective loss of delta + B cells. The mu + delta- cells of the splenic marginal zone were numerically unaltered. There was also a substantial residual mu + delta- B cell presence in the small lymphocyte compartment of follicles of LN and spleen in depleted animals. In addition, the blood selectively retained a mu + delta- B cell component. This was not derived from the spleen, as mu + delta- blood B cell numbers were sustained even where both halves of the spleen were irradiated. It is concluded that: (a) the major static B cell component of spleen and LN is mu + delta-, (b) that most if not all delta + B cells repeatedly migrate through the spleen and (c) there is a blood-born mu + delta- component which is resistant to depletion by splenic irradiation.,

Composition of urinary calculi collected in the Durban area

Three hundred urinary calculi were collected in the Durban area during the period August 1979--August 1980. Analysis by the X-ray diffraction method showed that their composition is generally similar to that found in the USA and UK. The incidence of uric acid, present in 17% of the calculi, is higher than that found overseas. There is a significantly higher incidence of calcium oxalate in calculi from Indians (83% v. 70% in Whites) while there is a significantly higher incidence of urinary apatite in Whites (35% v. 21% in Indians).

Oxidized copper wire particles for copper therapy in sheep

Ninety Merino weaner sheep were assigned to one of six groups on the basis of liveweight and liver copper concentrations. Sheep in four groups each received one oral dose of oxidized copper wire particles, viz. 2.5, 5, 10 or 20 g per animal. Sheep in another group each received a subcutaneous injection of 12 mg copper as diethylamino cupro-oxyquinoline sulfonate and another group of sheep did not receive any copper supplement. Liver copper concentrations responded positively to copper oxide load. The 2.5 g dose of copper oxide wire was more efficacious than the commercial injectable product in raising copper status, but the higher doses of oxide raised liver copper concentrations to values similar to those recorded in cases of copper poisoning. Copper concentrations in blood plasma, muscle and kidney were not altered by the copper load. No clinical signs, nor biochemical or histological evidence of acute copper toxicity, were found. Liver copper values fell in all sheep from 10 weeks after copper therapy until the end of the trial at 50 weeks post-therapy. Over this period of 40 weeks, the rate of mobilization of liver copper was linear and was positively related to the initial concentration of copper in the liver. A significant proportion of the oxidized copper wire dosed to sheep was recovered in the forestomachs and abomasa of selected sheep 4 weeks after dosing. No evidence of abomasal damage due to particles could be established. It is concluded that oral dosing of oxidized copper wire is a safe and effective method of copper supplementation to sheep.

Dextran's effects on stressed lenses: water, electrolyte, and radioisotope studies

To evaluate the beneficial effects of dextran 40 as an additive to infusion solutions, we studied an experimental model of lens stress with use of buffered, low calcium (Ca++)-containing solutions. Incubation in low Ca++ solutions (pCa = 10.7) for ten hours (stress period) resulted in lens swelling and electrolyte imbalances that were irreversible even with reincubation in physiologic, normal Ca++-containing media (pCa = 2.7) (recovery period). The addition of 6% or more of dextran to the media inhibited lens water gain during the stress period. It also rendered the resultant electrolyte imbalances reversible during the recovery period, thus exerting a protective effect. Radioisotope-tracer studies showed that dextran improved the ability of the lens to accumulate rubidium chloride Rb 86 and reduced its efflux during both the stress and recovery periods. Although dextran did not markedly decrease sodium chloride Na 22 uptake by lenses under stress, it did allow the lens to remove the 22Na during the recovery period.

Oral versus intravenous high-dose steroid treatment of renal allograft rejection. The big shot or not?

50 episodes of renal allograft rejection were treated by oral prednisolone and 49 by intravenous methylprednisolone. Both treatments achieved reversal of rejection in approximately 60% of episodes. Morbidity-rates, as assessed by hypertension, oliguria, fluid retention, and infection, tended to be greater after oral treatment. When the results were reexamined for accelerated, acute, and chronic rejection episodes the only difference demonstrated was an increased frequency of fluid retention in patients treated by oral prednisolone for an acute rejection episode. There was no evidence that intravenous methylprednisolone was nephrotoxic.

Inactivation of oriented bacteria with polarized ultraviolet light

Aligned deoxyribonucleic acid (DNA) molecules exhibit a large absorption anisotropy in the ultraviolet (UV) region of the spectrum (11). Also, the UV action spectra of most bacteria resemble the absorption spectrum of DNA (23), implying that inactivation is directly proportional to the UV absorbed by the bacterial DNA. Hence, the UV sensitivity of aligned uniaxial bacteria might be anisotropic with respect to polarization of the incident UV (17, 19). Any inactivation anisotropy would depend upon the orientation of DNA within the bacteria, as well as upon the alignment of bacteria, and could provide a more sensitive indication of in vivo DNA orientation than is presently available using optical methods (5, 12-16). Using an electric field of 3.5 x 10(6) cycles/second, samples of bacteria of strain LS-301 were aligned in a quartz cell and were irradiated with UV (lambda = 2652 A) polarized perpendicular and parallel to the alignment direction. The resultant survival curves resolved no inactivation anisotropy. This result is interpreted to mean that there was insufficient bacterial DNA alignment to give a detectable anisotropy. The minimum average DNA alignment necessary to have resolved an anisotropy is calculated to be 15 per cent in an axial direction (bases perpendicular to the bacterial axis) or 30 per cent in a radial direction (bases parallel to the bacterial axis).