Determinants of health-service use by low-income people.

Poverty influences health status, life expectancy, health behaviours, and use of health services. This study examined factors influencing the use of health-related services by people living in poverty. In the first phase, 199 impoverished users of health-related services in 2 large Canadian cities were interviewed by their peers. In the second phase, group interviews with people living in poverty (n = 52) were conducted. Data were analyzed using thematic content analysis. Diverse health-related services were used to meet basic and health needs, to maintain human contact, and to cope with life's challenges. Use of services depended on proximity, affordability, convenience, information, and providers' attitudes and behaviours. Use was impeded by inequities based on income status. To promote the health of people living in poverty, nurses and other health professionals can enhance the accessibility and quality of services, improve their interactions with people living in poverty, provide information about available programs, offer coordinated community-based services, collaborate with other sectors, and advocate for more equitable services and policies.     

The diagnosis of blocked cerebrospinal fluid shunts: a prospective study of referral to a paediatric neurosurgical unit

A prospective study was undertaken of all children referred to the Hospital for Sick Children with a provisional diagnosis of shunt blockage over a 5-month period. Fifty-two admissions were recorded, relating to 45 children, 5 of whom had multiple admissions. Only 19 of the 52 admissions led to a final diagnosis of shunt malfunction. No source of referral, whether by the child's general practitioner or from another hospital, was found to be more accurate than direct referral by the parents to the neurosurgical ward. Headache, vomiting and irritability were not significant indicators as to whether the child's shunt was actually blocked, and nor was the duration of the symptoms. Drowsiness was a significant, but not definite, indicator of shunt blockage, while pyrexia made it more likely that the patient had an alternative diagnosis. In 35 of the admissions a computed tomographic scan was performed: a normal scan, unchanged from previous scans, did not reliably exclude the diagnosis of shunt blockage. Percutaneous manometry via the reservoir of the shunt system was performed during 26 admissions: this investigation produced no false positives nor false negatives, but was equivocal in 5 cases, all of which were found at surgery to have a definite shunt blockage. The accuracy of the diagnosis of shunt blockage made prior to referral to a neurosurgical unit is discussed, together with the implications for resource use.     

A series of novel, highly potent and selective agonists for the kappa-opioid receptor.

1. This paper describes the opioid receptor pharmacology and in vivo activity of several novel benzene-acetamidopiperidine and benzeneacetamidopiperazine analogues. 2. These compounds all showed potent, naloxone-reversible, full agonist activity in the field-stimulated rabbit vas deferens, indicating that they are kappa-opioid agonists; but showed very little activity in the rat or hamster vas deferens, indicating good selectivity with regard to mu- and delta-opioid receptors. 3. They were all potent antinociceptive agents, the most potent compound, GR 103545, having an ED50 value in the mouse abdominal constriction test of 0.25 micrograms kg-1 s.c. The compounds also produced sedation and diuresis, but had little effect on respiration rate or gastrointestinal motility. 4. It is concluded that the seven novel compounds described are all potent and selective agonists for the kappa-opioid receptor.     

Relationship between intracranial pressure and intracranial volume in craniosynostosis.

Premature fusion of cranial sutures in craniosynostosis has been thought to lead to craniostenosis, which in turn may lead to increased intracranial pressures. In 41 consecutive patients with craniosynostosis, intracranial pressure and intracranial volume were measured. Of the 41 patients, 38 (92.6%) had raised intracranial pressure but only 4 (9.7%) had a decreased skull volume. In the present study, there is no correlation between intracranial volume and intracranial pressure. This study confirms that the measurement of intracranial volume, a non invasive procedure, cannot be used to assess intracranial pressure and to avoid an invasive procedure.     

Parental 'expressed emotion' as a predictor of schizophrenic relapse

Fifty-seven schizophrenic patients were initially assessed after admission to hospital, at which time their parents completed a Camberwell Family Interview, generating "expressed emotion" (EE) scores. Relapse over the next nine months was not predicted by household EE status or by individual EE scales. Multivariate analyses suggested that a poor course after hospitalization was best predicted by a poor course before admission and by living in a one-parent household. High household EE status was a predictor only in one multivariate analysis after course of illness and one-parent household status had been entered, suggesting an interaction effect. We query the causal proposition linking high EE and relapse and suggest instead that a poor illness course may elicit high EE in relatives, particularly in one-parent households, and, thus, may make the principal contribution to the proposed link.     

"Ia-like" antigens on human T cells.

Human T lymphocytes have been tested for cell surface p. 28,33 "Ia-like" heteroantigen and DRw alloantigens. Small numbers (1--5%) of sheep (E) rosette or T antigen-positive, surface immunoglobulin-negative (E+, T+, smIg-) T cells were Ia+; these cells appeared to be restricted to the TG subset. Following activation by allogeneic lymphocytes or sperm, or by purified protein derivative of tuberculin (PPD), the proportion of positive T cells increased substantially. DRw typing indicated that Ia specificities on activated T cells were not acquired passively from the stimulator cells, suggesting therefore that either "selection" of a small DRw+ cell subset or derepression and/or exposure of DR locus gene products occurs during T cell activation.     

Spontaneous activity of single neurones in the hypothalamus of rabbits during sleep and waking

1. A method is described for recording from single cells in the hypothalamus of unanaesthetized freely moving rabbits. Behaviour, bodily movement, skin and brain temperatures and e.e.g. were monitored.2. Patterns of unit firing during slow sleep, paradoxical sleep and waking were studied in several regions of the hypothalamus, thalamus and in the septum.3. Of the 144 cells analysed from waking to slow sleep, fifty-six (39%) decreased mean firing rates, thirty (21%) increased spike discharges and fifty-eight (40%) showed no marked change. Dorsal hypothalamic and massa intermedia thalamic cells fired in brief high frequency clusters during slow sleep with a characteristic ;bimodal' interspike interval histogram. Waking and paradoxical sleep abolished these cluster discharges with a concomitant change to an ;asymmetric' histogram.4. Of the thirty-two cells observed during the three states of waking, slow sleep and paradoxical sleep, a majority (twenty-five or 78%) showed their highest rates of spontaneous discharge during paradoxical sleep. Discharge rates of cells sometimes changed in the course of paradoxical sleep according to the presence or absence of phasic events such as myoclonic motor activity. Two hypothalmic cells were almost totally arrested during paradoxical sleep.5. Analysis of unit firing rates during spontaneous rises in brain temperature during waking and paradoxical sleep revealed that a majority of the neurones (22/24) changed their discharge rates in relation to behaviour rather than to brain temperature. Two cells did appear to respond specifically to the central thermal stimulus.6. Hypothalamic cells do not behave as a homogeneous population in relation to changes in the state of arousal of the rabbit. Spontaneous changes in cell discharge related to sleep-waking behaviour must be considered in any interpretation of hypothalamic unit activity as related to neuroendocrine or autonomic mechanisms.     

An orthotopic metastatic prostate cancer model in SCID mice via grafting of a transplantable human prostate tumor line

Metastasis is the major cause of prostate cancer deaths and there is a need for clinically relevant in vivo models allowing elucidation of molecular and cellular mechanisms underlying metastatic behavior. Here we describe the development of a new in vivo model system for metastatic prostate cancer. Pieces of prostate cancer tissue from a patient were grafted in testosterone-supplemented male NOD-SCID mice at the subrenal capsule graft site permitting high tumor take rates. After five serial transplantations, the tumor tissues were grafted into mouse prostates. Resulting tumors and suspected metastatic lesions were subjected to histopathological and immunohistochemical analysis. Samples of metastatic tissue were regrafted in mouse anterior prostates and their growth and spread examined, leading to isolation from lymph nodes of a metastatic subline, PCa1-met. Orthotopic grafting of PCa1-met tissue in 47 hosts led in all cases to metastases to multiple organs (lymph nodes, lung, liver, kidney, spleen and, notably, bone). Histopathological analysis showed strong similarity between orthotopic grafts and their metastases. The latter were of human origin as indicated by immunostaining using antibodies against human mitochondria, androgen receptor, prostate-specific antigen and Ki-67. Spectral karyotyping showed few chromosomal alterations in the PCa1-met subline. This study indicates that transplantable subrenal capsule xenografts of human prostate cancer tissue in NOD-SCID mice can, as distinct from primary cancer tissue, be successfully grown in the orthotopic site. Orthotopic xenografts of the transplantable tumor lines and metastatic sublines can be used for studying various aspects of metastatic prostate cancer, including metastasis to bone.