External alkalinization decreases intracellular Ca++ and spontaneous contractions in pregnant rat myometrium

OBJECTIVES

As plasma pH rises during pregnancy, the effect of raising external pH on spontaneous contractions in pregnant rat myometrium was investigated to test the hypothesis that elevated external pH depresses contraction.

STUDY DESIGN

Strips of longitudinal myometrium were loaded with SNARF (seminaphthorhodafluor) or Indo-1 for simultaneous intracellular pH or Ca++ and force measurements. Results were obtained from a minimum of five animals in each group, and significant differences were tested for by paired Student t tests.

RESULTS

Raising the external pH significantly reduced spontaneous force and calcium transient in the pregnant uterus. Raising the external pH led to a slow rise in intracellular pH, but this could not account for the functional effect. K+ rubidium 86-labeled efflux rates were unaffected by external pH, suggesting no hyperpolarization. The Ca++ channel agonist Bay K8644 (5 mumol/L) restored contractions abolished by raised external pH.

CONCLUSIONS

Raised external pH reduces spontaneous contractions in the pregnant rat uterus, probably by an external effect on Ca++ entry. This effect may contribute to uterine quiescence before term.

Women's sense of well-being before and after hysterectomy

OBJECTIVE

To describe women's perceived sense of well-being before and after hysterectomy by examining a broad array of outcomes experienced by women undergoing hysterectomies for benign conditions.

DESIGN

Prospective, descriptive.

SETTING

A regional tertiary care facility in central Texas.

PARTICIPANTS

One hundred seventy-eight women presenting for hysterectomies for nononcologic reasons who completed all three periods of data collection.

MAIN OUTCOME MEASURES

Subjects completed a questionnaire assessing information pertinent to their current gynecologic health and the SF-36 Health Survey before surgery and of 4 and 11 months after surgery. The women also completed the Zung Self-Rating Depression Scale preoperatively and at 4 months postoperatively. Additional demographic and medical information was extracted from the medical record.

RESULTS

In the initial period after surgery, the patients experienced an improved health status. In addition, the women reported on improvement in their psychologic well-being, including less depression and improved sexual functioning. Relationships with others also improved after the surgery.

CONCLUSIONS

Outcomes for these women undergoing hysterectomy for nononcologic reasons were generally positive. This information is vital for preoperative counseling by nurses of women contemplating or about to undergo this surgery.

Progress in the development of a transcutaneously powered axial flow blood pump ventricular assist system

Development of the Jarvik 2000 intraventricular assist system for long-term support is ongoing. The system integrates the Jarvik 2000 axial flow blood pump with a microprocessor based automatic motor controller to provide response to physiologic demands. Nine devices have been evaluated in vivo (six completed, three ongoing) with durations in excess of 26 weeks. Instrumented experiments include implanted transit-time ultrasonic flow probes and dual micromanometer LV/AoP catheters. Treadmill exercise and heart pacing studies are performed to evaluate control system response to increased heart rates. Pharmacologically induced cardiac dysfunction studies are performed in awake and anesthetized calves to demonstrate control response to simulated heart failure conditions. No deleterious effects or events were encountered during any physiologic studies. No hematologic, renal, hepatic, or pulmonary complications have been encountered in any study. Plasma free hemoglobin levels of 7.0 +/- 5.1 mg/dl demonstrate no device related hemolysis throughout the duration of all studies. Pathologic analysis at explant showed no evidence of thromboembolic events. All pump surfaces were free of thrombus except for a minimal ring of fibrin, (approximately 1 mm) on the inflow bearing. Future developments for permanent implantation will include implanted physiologic control systems, implanted batteries, and transcutaneous energy and data transmission systems.

Renal dysfunction does not alter the pharmacokinetics or LDL-cholesterol reduction of atorvastatin

The objective of this study was to determine the effects of renal dysfunction on the steady-state pharmacokinetics and pharmacodynamics of atorvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor. Nineteen subjects with calculated creatinine clearances ranging from 13 mL/min to 143 mL/min were administered 10 mg atorvastatin daily for 2 weeks. Pharmacokinetic parameters and lipid responses were analyzed by regression on calculated creatinine clearance. Correlations between steady-state atorvastatin pharmacokinetic or pharmacodynamic parameters and creatinine clearance were weak and, in general, did not achieve statistical significance. Although the elimination rate constant, lambda z (0.579), was significantly correlated with creatinine clearance, neither maximum plasma concentration (Cmax, -0.361) nor oral clearance (Cl/F, 0.306) were; thus, steady-state exposure is not altered. Renal impairment has no significant effect on pharmacodynamics and pharmacokinetics of atorvastatin.

Microsatellite evolution--a reciprocal study of repeat lengths at homologous loci in cattle and sheep

The application of microsatellites in evolutionary studies requires an understanding of the patterns governing their evolution in different species. The finding that homologous microsatellite loci are longer, i.e., containing more repeat units, in human and in other primates has been taken as evidence for directional microsatellite evolution and for a difference in the rate of evolution between species. However, it has been argued that this finding is an inevitable consequence of biased selection of longer-than-average microsatellites in human, because cloning procedures are adopted to generate polymorphic and, hence, long markers. As a test of this hypothesis, we conducted a reciprocal comparison of the lengths of microsatellite loci in cattle and sheep using markers derived from the bovine genome as well as the ovine genome. In both cases, amplification products were longer in the focal species, and loci were also more polymorphic in the species from which they were originally cloned. The crossing pattern that we found suggests that interspecific length differences detected at homologous microsatellite loci are the result of biased selection of loci associated with cloning procedures. Hence, comparisons of microsatellite evolution between species are flawed unless they are based on reciprocal analyses or on genuinely random selection of loci with respect to repeat length.

Expression of syndecan-1 in rabbit neointima following de-endothelialization by a balloon catheter

Enrichment of proteoglycans is prominent in early atherogenesis, contributing not only to SMC migration and proliferation, but also to low density lipoprotein retention. A family of integral cell membrane proteoglycans termed syndecans has recently been recognized. Among syndecans, syndecan-1, the first isolated member, has received most research attention. In this study, we examined the expression of syndecan-1 in rabbit aorta and aortic neointima, developed in response to a balloon catheter-induced de-endothelialization. The tissues were processed for Northern blot analysis, in situ hybridization, immunohistochemical staining and immunoblotting. Our results indicate that in normal aorta, the signal for syndecan-1 is weak. However, arterial injury induces syndecan-1 expression at both mRNA and protein levels. The presence of syndecan-1 in the neointimal tissue is persistent, prominent even at the 12th week after injury. Syndecan positive cells are distributed in the whole layer of the neointima, but are not visible in the underlying media. The presence of syndecan-1 in arterial neointima suggests a novel means of mediating interactions between neointimal cells and various agents, including extracellular matrix components, growth factors and lipoproteins.

Home health nurses: stress, self-esteem, social intimacy, and job satisfaction

A survey of 253 home health care nurses' perceptions of work-related stress, self-esteem, social intimacy, and job satisfaction found that stress has a negative correlation with self-esteem, social intimacy, and job satisfaction. A positive correlation, however, was found between self-esteem and social intimacy and job satisfaction. Health system administrators, owners, and directors had significantly higher levels of self-esteem, nurses with 5 years or more in their home health nursing position had significantly higher levels of self-esteem. The survey found that nurses with less than a baccalaureate degree possessed significantly lower levels of sociability than those with a graduate or baccalaureate degree. Administrators and managers scored significantly higher on sociability than head nurses.

CREB-binding protein/p300 are transcriptional coactivators of p65

CBP (CREB-binding protein) and p300 are versatile coactivators that link transcriptional activators to the basal transcriptional apparatus. In the present study, we identify CBP and p300 as coactivators of the nuclear factor-kappaB (NF-kappaB) component p65 (RelA). Consistent with their role as coactivators, both CBP and p300 potentiated p65-activated transcription of E-selectin and VCAM-1-CAT reporter constructs. The N- and C-terminal domains of both CBP/p300 functionally interact with a region of p65 containing the transcriptional activation domain as demonstrated by mammalian two-hybrid assays. Direct physical interactions of CBP/p300 with p65 were demonstrated by glutathione S-transferase fusion protein binding, and coimmunoprecipitation/Western blot studies. The adenovirus E1A 12S protein, which complexes with CBP and p300, inhibited p65-dependent gene expression. Reporter gene expression could be rescued from E1A inhibition by overexpression of CBP or p300. CBP and p300 act as coactivators of p65-driven gene activation and may play an important role in the cytokine-induced expression of various immune and inflammatory genes.

Peripheral blood is a source of BCR-ABL-negative pre-progenitors in early chronic phase chronic myeloid leukemia

Manipulation of autologous bone marrow cells (BM) for transplantation in chronic myeloid leukemia (CML) to enrich for normal cells is a novel approach that may improve survival for patients not suitable for allogeneic transplantation. Limitations of this technique include the reported low frequency of normal stem cells in CML and the difficulties in obtaining sufficient BM for manipulation. To address these problems we compared the apheresis product with the diagnostic bone marrow at diagnosis as a source of primitive BCR/ABL-negative progenitors. We analyzed the CD34+ HLA-DR- and CD34+CD38(-) populations in five CML patients to evaluate the frequency of BCR-ABL-negative progenitors and pre-progenitors in these populations. Progenitor analysis was performed by RT-PCR of individual hemopoietic colonies from a standard CFU-GM assay. Analysis of pre-progenitors involved RT-PCR of secondary colonies derived from a stroma-free pre-CFU assay. Our results show variable levels of BCR-ABL-negative progenitors in the 34+DR- population but very low levels of BCR-ABL-negative progenitors in the 34+38- population in blood. Analysis of pre-progenitors from the 34+DR- fraction of peripheral blood (PB) and BM showed 80-100% and 85-100% of colonies were BCR-ABL negative at days 14 and 28, respectively. Analysis of pre-progenitors from the 34+38- fraction of PB and BM showed 23-100% and 42-100% of colonies were BCR-ABL negative at days 14 and 28, respectively. In summary, pre-progenitors from the 34+DR- and 34+38- populations are predominantly BCR-ABL negative in both marrow and blood at diagnosis. Apheresis product collected at diagnosis is a more abundant sources of BCR-ABL-negative pre-progenitors than BM. Thus, apheresis product could potentially be utilized as a source of BCR-ABL-negative stem cells in CML.

Surgical treatment for thyroid cancer

Thyroidectomy procedures are the mainstay treatment for thyroid cancer and are safe and effective when they are performed by experienced surgeons. Preoperative evaluation of patients with suspected thyroid cancer consists of ultrasonography, radioisotope scanning, and computed tomography scans. Postoperative complications of thyroidectomy procedures include hemorrhage, edema of the glottis, muscle rigidity and spasm (ie, tetany), acute thyrotoxicosis, and damage to the laryngeal nerve. Most surgical patients are discharged home within three days after surgery, and many patients require lifelong thyroid hormone replacement to prevent hypothyroidism.

Surgical residents' scores on measures of Machiavellianism and physicians' uncertainty

51 self-reported scores on the Mach V Scale and 56 scores on Physician's Reactions to Uncertainty Constructs from surgical residents in three different specialties (30 general, 14 orthopedics, 9 urology, and 3 other) showed no significant difference between means on the two measures.

Isoprostanes: free radical-generated prostaglandins with constrictor effects on cerebral arterioles

BACKGROUND AND PURPOSE

Isoprostanes are generated by cyclooxygenase-independent free radical attack of arachidonic acid and are potent constrictors of the peripheral vasculature. Traumatic brain injury stimulates oxygen radical production and is associated with cerebral blood flow reduction. However, no specific vasoconstrictor has been identified as the cause of posttraumatic blood flow reduction. The purpose of this study was to determine whether isoprostanes constrict cerebral arterioles.

METHODS

The effects of 10(-9) to 10(-5) mol/L 8-iso-prostaglandin F2 alpha (8-iso-PGF2 alpha), 8-iso-prostaglandin E2 (8-iso-PGE2), and prostaglandin F2 alpha (PGF2 alpha) on pial arteriolar diameter were measured in anesthetized rats using a closed cranial window and in vivo microscopy.

RESULTS

All prostanoids produced vasoconstriction. Of these, 8-iso-PGF2 alpha produced the greatest vasoconstriction (34% +/- 2), followed by 8-iso-PGE2 (25% +/- 4) and PGF2 alpha (20% +/- 2). After six cerebrospinal fluid washouts of the cranial window, both 8-iso-PGF2 alpha- and 8-iso-PGE2-treated vessels remained slightly constricted, whereas the PGF2 alpha-treated vessels returned to control diameter. Coapplication of the semiselective thromboxane A2/prostaglandin H2 receptor antagonist SQ29548 completely blocked the vasoconstriction induced by 8-iso-PGF2 alpha and 8-iso-PGE2.

CONCLUSIONS

Isoprostanes are potent constrictors of cerebral arterioles and appear to act at a receptor that is similar to the thromboxane A2/prostaglandin H2 receptor. Isoprostanes may play a role in the reduction of cerebral blood flow that occurs after brain injury and subsequent oxygen radical production.

Injury-induced alterations in newly synthesized sulphated proteoglycans from rabbit arterial neointima covered by regenerated endothelium

Proteoglycan (PG) synthesis is a highly regulated, dynamic process that is known to be altered during atherogenesis. Endothelial injury, which may be the primary event in atherosclerosis, has been reported to stimulate PG synthesis and accumulation in the arterial extracellular matrix. The objective of this investigation was to study injury-induced alterations in PG synthesis and accumulation in the neointima, developed in response to a selective balloon catheter de-endothelialization of aortas of normocholesterolaemic rabbits. One group of rabbit aortas was incubated with 35S-Na2SO4 for 8 h, to study in vitro the de novo synthesis of sulphated PG. Another group of rabbit aortas was used to study PG accumulated in aortic neointima vs. PG present in intima-media of normal aortas. Newly synthesized sulphated PG was characterized by light microscopic radioautography and size exclusion chromatography. Purified intimal-medial PG extracts from unlabelled aortas were analysed for protein and glycosaminoglycan (GAG) content and GAG distribution pattern. Results from this study revealed that the neointima of injured aortas synthesized sulphated PG at a significantly higher concentration than the intima of normal aortas. Size exclusion chromatography revealed that neointima synthesized higher molecular weight PG, and in a higher proportion, than its counterpart PG from normal aortas. PG accumulated in neointima of injured aortas showed a significantly altered GAG distribution pattern. These data confirm that neointima developed in response to injury synthesizes and accumulates PG which is altered compared to PG present in the intima-media of normal aorta.

Home health nurses: stress, self-esteem, social intimacy, and job satisfaction

A survey of 67 home healthcare nurses' perception of work-related stress, self-esteem, social intimacy, and job satisfaction during corporate merging compared with a prior study of acute care surgical nurses (n = 71) during a merger of two hospitals found no difference between stress levels of home health nurses compared with acute care surgical nurses, which is contrary to popular belief.

Machiavellianism and radiographer job satisfaction

This article reports the results of a survey conducted to determine the relationship between Machiavellianism and job satisfaction among radiographers. As predicted by the literature, the survey showed a negative correlation between these two constructs-radiographers with higher Machiavellianism had lower job satisfaction, while those with the lowest Machiavellianism had the highest job satisfaction. Education, gender, marital status, race, position and time in position had no significant effect on the two constructs.

Evidence for glaucoma-induced horizontal cell alterations in the human retina

In this study we investigated changes to horizontal cells in human retinae affected by glaucoma. Glaucoma is characterized by raised intraocular pressure and is responsible for retinal ganglion cell and, possibly, photoreceptor degeneration. It was therefore assumed that horizontal cells might also be affected. The carbocyanine dye DiI was placed at discrete points on fixed, whole-mounted retinae obtained from normal and glaucomatous patients. After allowing 6-24 weeks for intramembranous diffusion within the lipid layers of the nerve cells and, therefore, fluorescent labeling, we measured horizontal cell soma and dendritic field sizes. Selected cells were then embedded in Araldite and cut at 4 microns. Horizontal cells in glaucomatous eyes appeared larger and had a granulated outline as compared with cells from normal retinae. Analysis of the mean cell soma size indicated that cells were 26% larger in the glaucomatous retinae and that this increase was significantly different from that seen in normal retinae (P < 0.05). The dendritic field size was unaffected (P > 0.05). As seen in cross section there was a clear loss of photoreceptor outer segments, and shrunken silhouettes of photoreceptor inner segments with pyknotic nuclei were observed. It is proposed that the increase in some size is indicative of horizontal cell responses that are likely to culminate in degeneration as a result of heightened intraocular pressure. In addition, this paper provides further evidence that photoreceptors are affected by advanced glaucoma.

[Considerations on the nursing discipline while approaching the year 2000]

A discipline is characterized by a unique perspective, a distinct way of viewing all phenomena, which ultimately defines the limits and nature of its inquiry (Donaldson & Crowley 1978). Further, Chinn & Jacobs (1987) define discipline as a branch of instruction; a body of knowledge and of systematizing that knowledge within an area of concern or domain of inquiry. The position taken in this paper is that nursing, as it approaches the year 2000, is an evolving discipline that is dedicated to the advancement of knowledge which contributes to the pursuit of excellence of care (AARN 1985). The writer agrees with Jennings' (1987) position that theory gives definition to nursing's body of knowledge, and direction to research and practice. This paper addresses some of the issues and concerns related to the development of nursing knowledge which serve as a cornerstone for the discipline. It goes on to consider briefly a few tasks that face nursing as it approaches the year 2000.

Synthesis of tissue inhibitor of metalloproteinase-1 (TIMP-1) in rabbit aortic neointima after selective de-endothelialization

Altered TIMP-1 synthesis in the arterial wall may be important for the balance between metalloproteinases and their inhibitors, and thus contribute to dysregulated extracellular matrix metabolism in atherosclerotic lesions. To examine this, we cloned the rabbit TIMP-1 gene from aortic neointima, developed in response to a balloon-catheter induced de-endothelialization. The apparent homology of cDNA with TIMP-1 genes from several sources suggested that it is a rabbit form of TIMP-1. We examined the recombinant rabbit TIMP-1 expression in Escherichia coli using the pTrxFus expression system and the synthesis of the resulting soluble protein was confirmed by immunostaining with anti-TIMP-1. The TIMP-1 concentration in normal and de-endothelialized rabbit aortas was compared using Northern blot, Western blot and mRNA in situ hybridization techniques. We observed a significant increase of TIMP-1 expression in neointimal SMCs at both nucleic acid and protein levels, suggesting a role of TIMP-1 in injury-induced atherogenesis.

Nurse evaluation of a pain medication protocol in a selective postoperative population

Postoperative pain in 33 patients who underwent radical prostatectomy was managed by an intramuscular nonsteroidal antiinflammatory drug protocol rather than by administration of narcotics. Patients rated their perception of pain with a visual analog scale on the first postoperative day both before and after receiving ketorolac tromethamine. The medication was effective in relieving pain after this major operation. Costs were approximately one half that of the traditional narcotic protocol used before this study.

The heterosexual singles scene: putting danger into pleasure

The juxtaposition of pleasure and danger has engaged many feminist theorists and researchers in the field of sexuality. This article presents a theoretical analysis of the ambiguous and complex relationship between 'pleasure', 'danger' and contemporary feminist theory. In doing so, it offers an understanding of the ways in which the categories of pleasure and danger operate within the discourses of heterosexuality to construct perceptions of risk in the context of HIV/AIDS. Data were collected from a study of the sexual attitudes and practices of 112 sexually-active, single, heterosexual adults (58 men and 54 women), aged 20 to 40 years (mean = 27 years) who agreed to be interviewed when approached at night-clubs and public "singles' bars around Melbourne, Australia. The qualitative analysis presented here is consistent with a poststructuralist feminism. First, we discuss how sexuality cannot be cast solely as pleasurable or dangerous. Second, we demonstrate how heterosexualized notions of pleasure and danger operate to provide misperceptions of risk from HIV/AIDS transmission. Third, we identify the ways in which the logic of identity functions to obscure risk within the discourse of heterosexuality, and finally we attempt to forge new ways of practising pleasure which disrupt heterosexist discourses and allow for pleasures which incorporate danger.