Effect of normobaric hyperoxia on two indexes of synaptic function in Fisher 344 rats

The physiological response of two central nervous system neurotransmitter receptors to oxidative stress was studied using the rat model of hyperoxia. We show that hyperoxia leads to a decline in the ability of isoproterenol (ISO) to augment GABAergic responses in cerebellar Purkinje neurons in vivo. This effect is reversed by the N-tert-butylalpha-phenylnitrone (PBN). We also show that hyperoxia produces a decline in the ability of oxotremorine (OXO) to stimulate dopamine (DA) release in striatal slices. This effect is accompanied by an increase in hydroxyl radical levels in the CNS reflected in an increase in 2,3-DHBA, suggesting that the change is the result of an increased level of oxidative stress. We also show a time dependent effect of hyperoxia on both beta-adrenergic and muscarinic receptor function. We examined the interaction between age and hyperoxia exposure and found that in 12-month-old rats there is a decline in the baseline response prior to oxygen exposure that may interfere with observing a subsequent effect of hyperoxia. Differential effects were observed between the cerebellum and striatum with respect to the interaction of age and time of oxygen exposure. Overall, the data suggest that age and hyperoxia may be acting via a common mechanism because there was no synergistic effect of the two conditions.

Laser wire for crossing chronic total occlusions: "learning phase" results from the U.S. TOTAL trial. Total Occlusion Trial With Angioplasty by Using a Laser Wire

The Prima laser guidewire system (Spectranectics Corp., Colorado Springs, CO) consists of an 0.018" hypotube containing a bundle of 45-microm optical fibers coupled to a pulsed excimer laser operating at a tip fluence of 60 ml/mm2 and a repetition rate ranging from 25-40 Hz. This laser guidewire was specifically designed to cross total occlusions refractory to passage with conventional wires. The Prima wire was evaluated in a feasibility study at 15 U.S. centers. Following failure to cross a total occlusion with approved guidewires, the Prima wire was utilized in 179 patients. Average age of subjects was 61 yr. Lesion locations included left anterior descending (36%), right (45%), and circumflex (19%) coronary arteries. Mean angiographic age of total occlusions was 70 wk (range, 2-1,020 wk, median, 14 wk). The use of the Prima wire either solely or in combination with conventional guidewires resulted in successful crossing in 61% of these previously impenetrable occlusions. Failure of the device was commonly related to length of the occlusion and tortuosity along the occluded pathway. Major complications included myocardial infarction in 7 patients (3.9%), tamponade in 3 (1.7%), and death in 2 (1.1%). This "learning phase" pilot study confirmed the feasibility of a laser guidewire in chronic total occlusions that are resistant to passage of conventional guidewires. An extended registry at these investigative sites is planned.

Prevalence estimates of cognitive impairment in medical model adult day health care programs

Despite an increasing emphasis on adult day health care (ADHC) programs as alternatives to institutional care for persons with dementia, little research based on direct assessment of clients' cognitive status has been conducted in such settings. The goal of this analysis was to estimate the prevalence of cognitive impairment among ADHC clients using commonly used screening measures. Age-adjusted and non-age-adjusted prevalence estimates of cognitive impairment in New York State ADHC programs were developed using a probability sample of 336 clients. Estimates were made using traditional cutting scores on standard cognitive screening measures, such as the Mini-Mental State Examination (MMSE), as well as latent class analyses applied to the same item sets. Average prevalence estimates of cognitive impairment were 55% across age cohorts and 60% for persons aged 65 and over. The MMSE yielded a prevalence estimate of 58% across age cohorts and 63% for those aged 65 and over. Using a more conservative cut score, the estimate for the MMSE was 33%; latent class estimates of moderate to severe impairment indicate that approximately 30% of the ADHC clients had cognitive impairment suggestive of probable or definite dementia. Community alternatives to institutional care for the elderly are increasing in popularity. These findings suggest that 1. While institutions are serving the most severely cognitively impaired, age-adjusted prevalence ratios for the ADHC sample approach the bounds of the institutional estimates. 2. The institutional setting will continue to be an important mode of care for the more severely impaired individuals. 3. Daycare is serving a high proportion of the mildly and moderately cognitively impaired individuals. It follows, therefore, that such programs need to address the needs of these individuals by developing specialized care plans and tracks targeted for the cognitively impaired.

Co-trimoxazole desensitization in HIV-seropositive patients

Co-trimoxazole (trimethoprim-sulphamethoxazole) is an effective prophylactic agent against Pneumocystis carinii pneumonia (PCP). However, it is associated with a high frequency of adverse reactions in immunocompromised patients which may preclude its use. Fourteen patients with a definite history of adverse reactions to co-trimoxazole on standard PCP prophylactic dosage were selected for desensitization using a regimen of gradual incremental exposure over an 11-day period. Eight (57.1%) were successfully desensitized and have continued on oral co-trimoxazole at maximum 21 months' follow-up. This report demonstrates that oral desensitization as an outpatient procedure is an effective and safe option for both primary and secondary PCP prophylaxis in HIV-seropositive patients with previous adverse drug reactions.

HOX homeobox genes exhibit spatial and temporal changes in expression during human skin development

The spatial and temporal deployment of HOX homeobox genes along the spinal axis and in limb buds during fetal development is a key program in embryonic pattern formation. Although we have previously reported that several of the HOX homeobox genes are expressed during murine skin development, there is no information about developmental expression of HOX genes in human skin. We have now used reverse transcriptase polymerase chain reaction, in conjunction with a set of degenerate oligonucleotide primers, to identify a subset of HOX genes that are expressed during human fetal skin development. In situ hybridization analyses demonstrated that there were temporal and spatial shifts in expression of these genes. Strong HOXA4 expression was detected in the basal cell layers of 10 wk fetal epidermis and throughout the epidermis and dermis of 17 wk skin, whereas weak signal was present in the granular layer of newborn and adult skin. The expression patterns of HOXA5 and HOXA7 were similar, but their expression was weaker. In situ hybridization analysis also revealed strong HOXC4 and weaker HOXB7 expression throughout fetal development, whereas HOXB4 was expressed at barely detectable levels. Differential HOX gene expression was also observed in developing hair follicles, and sebaceous and sweat glands. None of the HOX genes examined were detected in the adult dermis.

Measurement choices in multi-site studies of outcomes in dementia

This paper summarizes the measurement choices made by selected current or recently completed multi-site projects with a common emphasis on measuring outcomes in dementia. Information on number of items and scoring, reason(s) for selecting the measure, and reliability and validity of the measure (either citations providing this information or a report of pertinent unpublished findings) is presented for eight domains: cognition, behavioral symptoms, physical health status, physical functioning and self-care abilities, quality of life, family/staff caregiver outcomes, service use, and cost. We found considerable reliance on the published literature as a guide to measurement choice, motivated largely by measures' superior psychometric properties, their ubiquity in the literature, and/or their brevity or ease of use. There is still evidence of "starting from scratch" in some domains, however. To the extent that these projects reflect the state of the art in dementia-relevant outcomes research, we conclude that comparison of outcomes across studies will continue to be problematic. However, as long as dissemination of methodological as well as substantive findings continues to characterize outcome studies in dementia, there is hope that a more congruent view of how to assess key outcomes in dementia will emerge.

Methodological issues in cognitive assessment and their impact on outcome measurement

Assessment of cognitive impairment in chronic care populations is complicated by several factors that may interfere with the assessment process: physical frailty and disability; comorbid conditions such as depression; and decrements in vision, hearing, speech, and general communication. Moreover, cognitive impairment itself affects assessment of outcome domains such as depression, behavior, and function, thus contributing to several sources of measurement bias. Sources of bias are discussed in the context of findings from the literature relating individual and cognitive factors to outcome measurement. Recommendations for further methodological research are provided.

Bone morphogenetic protein-2 induces scar formation and skin maturation in the second trimester fetus

Fetal mammals heal skin wounds through the second trimester of development without evidence of scar. We have investigated the role of bone morphogenetic protein 2 (BMP-2), which is a member of the TGF-beta superfamily, in normal skin development and fetal wound healing. We first used RNA in situ hybridization to demonstrate that BMP-2 was expressed at low levels in the developing hair follicles and in the epidermis of normal human fetal skin. We then created an in vivo model to test how exogenous BMP-2 would affect fetal skin development and wound healing. Fifty micrograms of BMP-2 was implanted into the subcutis of five 70-day-old fetal lambs through a full-thickness linear incision. The BMP-2 was placed beneath the right half of the wound, whereas the left half served as an untreated control. In two of the five animals 1 microgram of TGF-beta was placed into the same position in addition to the 50 micrograms of BMP-2. Twenty days later (90 days gestation, term = 140 days) all the fetal wounds were examined for evidence of cellular hyperproliferation and scar formation. BMP-2 induced massive dermal and epidermal growth when compared with controls. This finding was characterized by marked epidermal thickening and keratinization, a dramatic increase in the number of hair follicles, and more than 50 percent thickening of the dermis. The dermal thickening was the result of both increased cellularity and deposition of large irregular collagen bundles. Wounds treated with both BMP-2 and TGF-beta healed also with an adult-like pattern of scar formation. Surprisingly, the wounds with BMP-2 alone healed with an equal pattern of scar, indicating that there was not an additive effect of combining BMP-2 and TGF-beta. We conclude that BMP-2 is a pleomorphic growth factor that induces cellular growth, maturation, and fibroplasia in both the dermis and epidermis. Further analysis of this growth factor in both fetal and adult wound healing may lead to important discoveries regarding the control of scar formation and fibrosis in many adult tissues.

Prevalence of behavior disorder and disturbance to family and staff in a sample of adult day health care clients

Latent class-derived prevalence estimates of behavior disorder are provided for adult day health care (ADHC) clients; informal and formal caregivers reported 11% and 14%, respectively, of these clients as engaging in severe disturbed behavior (95% confidence intervals across sources are from 7% to 18%). The prevalences, estimated for informal and formal caregivers respectively, were 12% and 16% for affective disorder, 15% and 18% for cognitive disorders, 16% and 13% for verbal-vocal agitation, and 6% and 8% for socially inappropriate behavior. These rates can be contrasted with those of the institutional population which, while higher, overlap with the distribution of behavior disorder for ADHC community residents. The degree of reported disturbance to family and staff was similar across items.

The human homeobox genes MSX-1, MSX-2, and MOX-1 are differentially expressed in the dermis and epidermis in fetal and adult skin

In order to identify homeobox genes which may regulate skin development and possibly mediate scarless fetal wound healing we have screened amplified human fetal skin cDNAs by polymerase chain reaction (PCR) using degenerate oligonucleotide primers designed against highly conserved regions within the homeobox. We identified three non-HOX homeobox genes, MSX-1, MSX-2, and MOX-1, which were differentially expressed in fetal and adult human skin. MSX-1 and MSX-2 were detected in the epidermis, hair follicles, and fibroblasts of the developing fetal skin by in situ hybridization. In contrast, MSX-1 and MSX-2 expression in adult skin was confined to epithelially derived structures. Immunohistochemical analysis of these two genes suggested that their respective homeoproteins may be differentially regulated. While Msx-1 was detected in the cell nucleus of both fetal and adult skin; Msx-2 was detected as a diffuse cytoplasmic signal in fetal epidermis and portions of the hair follicle and dermis, but was localized to the nucleus in adult epidermis. MOX-1 was expressed in a pattern similar to MSX early in gestation but then was restricted exclusively to follicular cells in the innermost layer of the outer root sheath by 21 weeks of development. Furthermore, MOX-1 expression was completely absent in adult cutaneous tissue. These data imply that each of these homeobox genes plays a specific role in skin development.

Sexual expression and dementia. Views of caregivers: A pilot study

OBJECTIVE

To measure the attitudes of health professionals in nursing homes towards sexuality and sexual expression in cognitively impaired and cognitively intact residents.

DESIGN

Postal survey.

PARTICIPANTS

The staff (administrators, clinicians, social workers and others) of 300 randomly selected nursing homes located in three states. Of these, 114 representatives responded.

MAIN OUTCOME MEASURE

A measure of attitudes towards resident sexuality developed during a prior study.

RESULTS

Results suggest that respondents held a generally positive orientation towards residents' sexual expression which was expressed with respect to cognitively impaired residents as well as to those who were cognitively intact. Possibly because of the small sample size and resulting low statistical power, statistical analyses failed to demonstrate any significant differences among the groups of residents: administrators, clinicians, social workers, and undifferentiated 'others'. However, while non-significant, there was a consistent tendency for administrators to be relatively more conservative than were the other groups. Almost all respondents agreed that additional staff training should focus specifically on dealing with resident sexual expression.

CONCLUSIONS

Overall, the sample reported generally positive attitudes towards resident sexuality and sexual expression.

Relation of operator volume and experience to procedural outcome of percutaneous coronary revascularization at hospitals with high interventional volumes

BACKGROUND

Although an inverse relation between physician caseload and complications has been conclusively demonstrated for several surgical procedures, such data are lacking for percutaneous coronary intervention, and the ACC/AHA guidelines requiring > or = 75 cases per year for operator "competency" are considered by some physicians to be arbitrary.

METHODS AND RESULTS

From quality-controlled databases at five high-volume centers, models predictive of death and the composite outcome of death, Q-wave infarction, or emergency bypass surgery were developed from 12,985 consecutively treated patients during 1993 through 1994. Models had moderate to high discriminative capacity (area under ROC curves, 0.65 to 0.85), were well calibrated, and were not overfitted by standard tests. These models were used for risk adjustment, and the relations between both yearly caseload and years of interventional experience and the two adverse outcome measures were explored for all 38 physicians with > or = 30 cases per year. The average physician performed a mean +/- SD of 163 +/- 24 cases per year and had been practicing angioplasty for 8 +/- 5 years. Risk-adjusted measures of both death and the composite adverse outcome were inversely related to the number of cases each operator performed annually but bore no relation to total years of experience. Both adverse outcomes were more closely related to the logarithm of caseload (for death, r = .37, P = .01; for death, Q-wave infarction, or bypass surgery, r = .58, P < .001) than to linear caseload.

CONCLUSIONS

In this analysis, high-volume operators had a lower incidence of major complications than did lower-volume operators, but the difference was not consistent for all operators. If these data are validated, their implications for hospital, physician, and payer policy will require exploration.

Intravitreal injection of octreotide acetate

This study was conducted to determine the feasibility of injecting the somatostatin analogue, octreotide acetate (OA), into the vitreous cavity. Previous work suggests that octreotide effectively inhibits angiogenesis in vitro, thus its use in vivo may slow the progression of proliferative eye disease. Fifty micrograms of aqueous OA in 50 microliters aqueous solution was injected into the mid-vitreous of kitten eyes (n = 6), and OA levels were monitored over 4 days. A long-acting release form of octreotide (OA-LAR) was also injected into the mid-vitreous of rabbit eyes at doses of 0.36 (n = 16), 1.1 (n = 1), 2.1 (n = 1), 4.05 (n = 1), 8.2 (n = 1), and 36 mg (n = 3) in solution; and octreotide concentrations were measured at various time points over 42 days. OA concentrations were determined by a highly specific radioimmunoassay. Aqueous octreotide was eliminated rapidly (t1/2 = 16 hours) from the vitreous of the kitten eye, with only negligible amounts recoverable 4 days post-injection. In the long-acting form, OA in the rabbit eye reached peak levels at 28 days. By 42 days, OA levels had declined to the 14-day level. Doses of OA-LAR of 1.1 mg or less produced no gross evidence of clinical toxicity and elicited no grossly visible ocular side effects. Doses greater than 1.1 mg produced significant toxicity, including cataracts and rubeosis. The 28-day peak release for long-acting OA implies that monthly intravitreal injections could provide continual high levels of OA. Intravitreal injection of long-acting OA provides sustained, high concentrations of drug, and deserves further study as a potential treatment of proliferative eye diseases.

Reporting source bias in estimating prevalence of cognitive impairment

Reporting source bias was examined using cognitive data from a probability sample of adult day health care (ADHC) clients. Data were obtained from four sources: client, family, staff, and chart. These data suggest that prevalence estimates are influenced by the reporting source and method of assessment, with chart diagnoses yielding the least convergent estimates. Examination of agreement summary statistics and bias indices show that both staff and family underreport prevalence of cognitive impairment, but that more bias is associated with staff than is with family sources. Such bias should be considered in studies of prevalence estimation of cognitive impairment.

A genetic linkage study of the D2 dopamine receptor locus in heavy drinking and alcoholism

BACKGROUND

Reports of an association between restriction fragment length polymorphisms (RFLPs) at the dopamine D2 receptor (DRD2) locus and alcoholism have suggested involvement of that locus in the aetiology of alcoholism.

METHOD

Sib pair linkage analyses were conducted in families multiply affected by alcoholism, using both the Taql 'A' RFLP and a microsatellite repeat polymorphism at the DRD2 locus.

RESULTS

The 'Identical By Descent' analysis provided significant evidence of an effect of the DRD2 locus on the liability to develop heavy drinking (P < 0.0016) and Research Diagnostic Criteria alcoholism (P < 0.0003) in the first sample of families studied. However, this result was explicable by the segregation of alleles in a single large sibship, and it was not replicated in a second sample of families.

CONCLUSIONS

The results do not support linkage between the DRD2 locus and alcoholism in most of the families studied. It remains possible that this locus influences the predisposition to alcoholism in some families.

Environmental health competencies: a survey of nurse practitioner programs

Because of widespread public and governmental concern about the health effects of environmental hazards and exposure in recent years, and the increasing incidence of environmentally induced diseases, it is important that primary care nurse practitioners possess the knowledge and skills to effectively address environmental health as a component of their practice. A mailed questionnaire survey of 187 United States' nurse practitioner (NP) programs was conducted, with a response rate of 64%, to determine: 1) current and ideal emphasis on environmental health, 2) faculty preparation for teaching environmental health, 3) environmental health competencies expected of graduates, 4) didactic and clinical contact hours devoted to environmental health, and 5) barriers and incentives to greater emphasis on environmental health. Findings reveal that more than two thirds of NP program directors believe there should be greater emphasis on environmental health in their programs, but expressed concerns about overcrowded curricula and lack of faculty preparation as barriers to change. Competencies with the highest mean ratings included understanding the relationship between environmental hazards and human health, accessing information resources related to environmental hazards and health, and counseling clients about how they can reduce risks associated with environmental hazards. The two factors identified as most likely to increase the emphasis on environmental health in NP programs were having nurse faculty with expertise and being able to access information resources related to environmental health. Currently, insufficient attention is given to environmental health in NP education programs.

Chlorhexidine spray effects on plaque accumulation in developmentally disabled patients

Chlorhexidine gluconate has been studied as an adjunct to standard oral hygiene techniques in developmentally disabled patients in reducing plaque accumulation. The purpose of this double blind crossover study was to determine the efficacy of two concentrations of chlorhexidine spray (0.12% and 0.06%) on plaque accumulation in developmentally disabled patients. Informed consent was obtained for 8 developmentally disabled patients 12 to 33 years of age. Patients were randomly assigned to one of two groups of four each. One group received twice daily 0.12% chlorhexidine spray while the other received the 0.06% chlorhexidine spray for 30 days, followed by twice daily chlorhexidine spray (0.12% and 0.06%) alternating groups, for a period of 30 days. Final plaque indices were determined. Normal oral hygiene practices continued throughout the study. Significant plaque reduction occurred with the 0.12% and 0.06% spray solutions. No significant differences occurred between the two concentrations. The results of this study suggest that twice daily chlorhexidine spray at a concentration of 0.06% is as effective in reducing plaque accumulation as a 0.12% chlorhexidine concentration.

Environmental Health Competencies: A Survey of U.S. Nurse Practitioner Programs

Because of widespread public and governmental concern about the health effects of environmental hazards and exposure in recent years, and the increasing incidence of environmentally-induced diseases, it is important that primary care nurse practitioners possess the knowledge and skills to effectively address environmental health as a component of their practice. A mailed questionnaire survey of 187 U.S. nurse practitioner (NP) programs was conducted, with a response rate of 64%, to determine: 1) current and ideal emphasis on environmental health, 2) faculty preparation for teaching environmental health, 3) environmental health competencies expected of graduates, 4) didactic and clinical contact hours devoted to environmental health, and 5) barriers and incentives to greater emphasis on environmental health. Findings reveal that more than two-thirds of NP program directors believe there should be greater emphasis on environmental health in their programs, but expressed concerns about overcrowded curricula and lack of faculty preparation as barriers to change. Competencies with the highest mean ratings included understanding the relationship between environmental hazards and human health, accessing information resources related to environmental hazards and health, and counseling clients about how they can reduce risks associated with environmental hazards. The two factors identified as most likely to increase the emphasis on environmental health in NP programs were having nurse faculty with expertise and being able to access information resources related to environmental health. Currently, insufficient attention is given to environmental health in nurse practitioner education programs.