The effect of systemic arterial hypertension on blood-to-tissue transport in experimental gliomas

Systemic arterial hypertension was induced with epinephrine in 15 rats with 39 transplanted RG-2 brain tumors in an attempt to increase blood-to-tissue transport of a water-soluble compound. In 4 rats, hypertension was induced acutely (< 5 sec), and in 11 hypertension was induced more slowly (over 5 min). Regional values of the unidirectional blood-to-tissue transfer constant (K) of alpha aminoisobutyric acid were measured with quantitative autoradiography. Mean arterial blood pressure (BP) over the experimental period increased from 117 ± 17 mmHg (SD) to 168 ± 18 mmHg in the rats with slowly induced hypertension, and from 124 ± 4 to 142 ± 5 mmHg in the acute hypertension group. Peak BP was 208 ± 16 in the first group and 216 ± 13 mmHg in the second. Intracerebral hemorrhage occurred in 10/15 animals, and there was disruption of BBB in tumor-free brain in 10/15 animals. Averaged mean whole tumor K of AIB in all hypertensive rats was 0.052 ± 0.022 ml/g/min, compared to 0.037 ± 0.015 ml/g/min in normotensive controls; there was no difference in mean tumor K between the two hypertensive groups. However, in intraparenchymal tumors without hemorrhage, K was only 0.039 ± 0.013 ml/g/min. Although the mean K of AIB was higher in brain tumors of the hypertensive rats, the increase is unlikely to be meaningful in terms of augmented delivery of watersoluble drugs to brain tumors, and the high incidence of intracerebral hemorrhage countermands any clinical use of this approach.     

Interferon alpha/beta and interleukin 12 responses to viral infections: pathways regulating dendritic cell cytokine expression in vivo

Interferon (IFN)-alpha/beta and interleukin (IL)-12 are cytokines critical in defense against viruses, but their cellular sources and mechanisms of regulation for in vivo expression remain poorly characterized. The studies presented here identified a novel subset of dendritic cells (DCs) as major producers of the cytokines during murine cytomegalovirus (MCMV) but not lymphocytic choriomeningitis virus (LCMV) infections. These DCs differed from those activated by Toxoplasma antigen but were related to plasmacytoid cells, as assessed by their CD8alpha(+)Ly6G/C(+)CD11b(-) phenotype. Another DC subset (CD8alpha(2)Ly6G/C(-)CD11b(+)) also contributed to IL-12 production in MCMV-infected immunocompetent mice, modestly. However, it dramatically increased IL-12 expression in the absence of IFN-alpha/beta functions. Conversely, IFN-alpha/beta production was greatly reduced under these conditions. Thus, a cross-regulation of DC subset cytokine responses was defined, whereby secretion of type I IFNs by CD8alpha(+) DCs resulted in responses limiting IL-12 expression by CD11b(+) DCs but enhancing overall IFN-alpha/beta production. Taken together, these data indicate that CD8alpha(+)Ly6G/C(+)CD11b(-) DCs play important roles in limiting viral replication and regulating immune responses, through cytokine production, in some but not all viral infections. They also illustrate the plasticity of cellular sources for innate cytokines in vivo and provide new insights into the roles of IFNs in shaping immune responses to viruses.     

Effects of a Relationship-Enhancing Program of Care on Outcomes

Purpose: To examine the effects of a relationship-enhancing program of care (REPC) on resident and care provider outcomes.
Design and Methods: A quasi-experimental, repeated measures design, with intervention and comparison groups. Questionnaires were distributed to 50 residents, and observations were conducted of 40 residents and 34 nursing staff at baseline and 3 months after the intervention, on two Canadian nursing home units. An investigator-designed educational program based on Winnicott's theory of relationships and the empirical literature, was provided to care providers and their supervisors on the intervention unit. Repeated measures analysis of variance (RM-ANOVA) was used to compare the intervention and comparison groups in regard to changes in the outcomes over time.
Findings: The REPC had statistically significant effects on (a) residents' perceptions of care providers' relational care, (b) care providers' relational behaviors, and (c) continuity of care.
Conclusions: Evidence showed that these care providers were taught how to enhance their relational skills with residents living in long-term care facilities without added staff. Recommendations for practice and research are discussed.     

Partnership in research: a tandem of opportunities and constraints

Partnership is a term that is occurring more and more frequently in the research lexicon, an approach that is gradually becoming a sine qua non in the field of health and healthcare research in Canada. The purpose of this article is to share thoughts and experiences regarding research carried out in partnership. The relevance and necessity of partnerships in strategic health research will be examined, and the contribution of partnerships to the development and "re-centring" of intra- and interdisciplinary knowledge and knowledge transfer will be discussed. Based on the nursing and related-fields literature, the key elements of partnership, and the advantages and disadvantages of this strategy to pursuing research projects will be presented. An important issue in a professional discipline such as nursing will be discussed, i.e. the intra-disciplinary partnership between researchers and clinicians. Strategies that could enhance this particular type of partnership and avenues for catalyzing the synergy that must perforce develop, over the coming years, will be proposed.     

Caregivers of elderly people with loss of autonomy in Lebanon: what is the context of their health care?

The primary objective of this pan Lebanese study was to describe the health care context of family caregivers cohabiting with an elderly relative with loss of autonomy while the secondary objective consisted in the qualitative documentation of their positive and negative perceptions as to the role of the caregivers. The study uses a theoretical framework of stress. The results indicate that the caregivers (N = 319) take care of relatives (40% with memory troubles) having a moderate level of loss of autonomy and who present more depressive behaviors than "disturbing" behaviors. The caregivers are particularly affected by the behaviors of their relatives. They accomplish several health care tasks and very few receive formal services to support them. Their neighborhood offers them more emotional support than instrumental support. More caregivers perceive positive aspects than negative aspects in their role. Recommendations are formulated to guide the elaboration of a national policy of support to caregivers and the development of innovative community care practices.     

The Stimulus-Secretion Coupling of Glucose-Induced Insulin Release. VII. A PROPOSED SITE OF ACTION FOR ADENOSINE-3′,5′-CYCLIC MONOPHOSPHATE

Glucose-induced insulin release is thought to result from the following sequence of events in the beta cell: glucose metabolism leading to the production of a metabolic signal, net calcium uptake by the beta cell in response to the signal, and interaction between calcium and a microtubular-microfilamentous system, leading to emiocytosis of the secretory granules. Dibutyryl-cyclic AMP (db-cAMP) and theophylline are known to potentiate glucose-induced insulin release, their insulinotropic action being most marked at high glucose concentrations. Based on the above mentioned concepts, it was considered in the present experiments that the primary site of action of cAMP in the beta cell could correspond to either a facilitation of glucose metabolism, a modification of calcium distribution, or an interaction with the microtubular-microfilamentous system.The first of these hypotheses appeared unlikely because db-cAMP and theophylline, in sharp contrast with other agents known to affect glucose metabolism in the beta cell, did not modify glucose-induced calcium uptake by isolated islets incubated at high glucose concentrations. The last hypothesis also appeared unlikely since theophylline did not interfere with the deleterious effect of colchicine on the microtubular system, and since vincristine or colchicine did not differentially affect the respective insulinotropic action of glucose and theophylline. An effect of cAMP upon calcium distribution in the beta cell was suggested by the following findings. Whereas glucose and leucine were unable to promote insulin release in the absence of extracellular calcium, the addition of db-cAMP or theophylline to the calcium-depleted media partially restored theinsulinotropic action of glucose and leucine. Moreover, theophylline caused a dramatic increase in (45)Ca efflux from perifused islets, even in the absence of glucose. It is concluded that the insulinotropic action of cAMP could be due to a glucose-independent translocation of calcium within the beta cell, from an organelle-bound pool to a cytoplasmic pool of ionized calcium readily available for transport across the cell membrane.     

Cross-cultural adaptation of the Pelvic Girdle Questionnaire (PGQ) into Brazilian Portuguese and clinimetric testing of the PGQ and Roland Morris questionnaire in pregnancy pelvic pain

Objective

To translate and cross-culturally adapt the Pelvic Girdle Questionnaire (PGQ) into Brazilian Portuguese and test the measurement properties of the PGQ and the Roland Morris Disability Questionnaire (RMDQ) in women with pelvic pain during pregnancy.