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Determination of Postmortem Interval in Mice. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2024. [PMID: 38471755 DOI: 10.30802/aalas-jaalas-23-000107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
Despite the major use of mice in biomedical research, little information is available with regard to identifying their postmortem changes and using that information to determine the postmortem interval (PMI), defined as the time after death. Both PMI and environmental conditions influence decomposition (autolysis and putrefaction) and other postmortem changes. Severe decomposition compromises lesion interpretation and disease detection and wastes limited pathology resources. The goal of this study was to assess postmortem changes in mice in room temperature cage conditions and under refrigeration at 4 °C to develop gross criteria for the potential value of further gross and histologic evaluation. We used 108 experimentally naïve C57BL/6 mice that were humanely euthanized and then allocated them into 2 experimental groups for evaluation of postmortem change: room temperature (20 to 22 °C) or refrigeration (4 °C). PMI assessments, including gross changes and histologic scoring, were performed at hours 0, 4, 8, and 12 and on days 1 to 14. Factors such as temperature, humidity, ammonia in the cage, and weight change were also documented. Our data indicates that carcasses held at room temperature decomposed faster than refrigerated carcasses. For most tissues, decomposition was evident by 12 h at room temperature as compared with 5 d under refrigeration. At room temperature, gross changes were present by day 2 as compared with day 7 under refrigeration. Mice at room temperature lost 0.78% of their baseline body weight per day as compared with 0.06% for refrigerated mice (95% CI for difference 0.67% to 0.76%, P < 0.0005). This study supports the consideration of temperature and PMI as important factors affecting the suitability of postmortem tissues for gross and histologic evaluation and indicates that storage of carcasses under refrigeration will significantly slow autolysis.
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Physiologic and Behavioral Effects in Mice Anesthetized with Isoflurane in a Red-tinted or a Traditional Translucent Chamber. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2022; 61:322-332. [PMID: 35840316 PMCID: PMC9674017 DOI: 10.30802/aalas-jaalas-22-000011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Isoflurane has been characterized as a distressing agent for rodents, causing both physiologic and behavioral effects. Using a "darkened home cage" has been recommended during CO₂ administration for rodent euthanasia; this is arguably a similar animal experience to anesthetic induction with isoflurane. Based on the premise that rodents perceive red light as darkness via the primary optic tract, we compared physiologic and behavioral markers of stress in 2 inbred strains of mice (C57BL/6J and BALB/cJ) anesthetized with isoflurane in either a red-tinted (dark) induction chamber or a traditional translucent induction chamber. Physiologic stress was assessed based on plasma levels of norepinephrine, epinephrine, and corticosterone. Stress-related behaviors (rearing, face wiping, and jumping) were recorded on video and scored from initiation of induction to loss of consciousness. No significant correlations were found between chamber type and physiologic stress hormones. As compared with the translucent chamber, stress-related behaviors were more frequent in the red-tinted chamber, including: 1) significantly higher rearing frequencies in BALB/cJ mice; 2) higher behavioral stress scores in BALB/cJ and male C57BL/6J mice; and 3) more face wiping behavior when considering all mice combined. These findings suggest that mice do not experience significant alleviation of physiologic indices of stress when anesthetized in a red-tinted induction chamber. Furthermore, isoflurane induction in the red-tinted chamber appeared to increase the expression of stress-related behaviors, particularly in BALB/cJ mice. Based on our findings and a growing body of literature on the unintended effects of red light, we do not recommend using red-tinted chambers for induction of anesthesia in mice.
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Abstract
OBJECTIVE This study describes the population of HIV-infected adults receiving care in rural areas of the United States and compares HIV care received in rural and urban areas. METHODS Interviews were conducted with a nationally representative sample of 367 HIV-infected adults receiving health care in rural areas and 2806 HIV-infected adults receiving health care in urban areas of the contiguous United States. RESULTS We estimate that 4800 HIV-infected persons received medical care in rural areas during the first half of 1996. Patients in rural HIV care were more likely than patients in urban HIV care to receive care from providers seeing few (<10) HIV-infected patients (38% vs. 3%; p <.001). Rural care patients were less likely than urban care patients to have taken highly active antiretroviral agents (57% vs. 73%; p <.001) or Pneumocystis carinii pneumonia prophylactic medication when indicated (60% vs. 75%; p =.006). CONCLUSIONS Few American adults received HIV care in rural areas of the United States. Our findings suggest ongoing disparities between urban and rural areas in access to high-quality HIV care.
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Breast cancer action plan for Kentucky. THE JOURNAL OF THE KENTUCKY MEDICAL ASSOCIATION 2001; 99:437-44. [PMID: 11668903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
In 1998, Governor Paul E. Patton established the Kentucky Breast Cancer Task Force (KBCTF) to assess and make recommendations on the availability, accessibility, utilization, quality, and outcomes of breast cancer services across the spectrum of disease. Over a two-year period, the KBCTF reviewed the state of breast cancer control in Kentucky and made recommendations for reducing breast cancer morbidity and mortality. To achieve the provision of optimal breast cancer care, the KBCTF recommended universal adoption of professionally accepted guidelines for breast cancer treatment, pain management, and distress management. To better coordinate public education on breast cancer, the KBCTF recommended the development of a standardized packet of public education materials for dissemination through regional networks of "cancer control partners." KBCTF members also requested the Kentucky Cancer Program to investigate the feasibility of establishing a centralized mammography registry to gather more complete data on screening mammography programs.
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Who receives Ryan White CARE Act services? A demographic comparison of CARE act clients and the general AIDS population. AIDS Patient Care STDS 2000; 14:561-5. [PMID: 11054941 DOI: 10.1089/108729100750018335] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
This study examines the extent to which health and social service providers funded by the Ryan White Comprehensive AIDS Resources Emergency (CARE) Act serve women, minorities, and other vulnerable populations emphasized by the legislation. Demographic characteristics of AIDS-diagnosed clients served by CARE Act-funded providers in four metropolitan areas and two states are compared with Centers for Disease Control and Prevention estimates of AIDS prevalence. Clients of CARE Act-funded providers tend to reflect the demographics of local HIV/AIDS epidemics. Where differences exist, CARE Act clients are more likely to be women and minorities and less likely to be injecting drug users. CARE Act-funded providers are effectively reaching most medically underserved populations.
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Rural HIV-service networks: patterns of care and policy issues. AIDS & PUBLIC POLICY JOURNAL 2000; 11:36-46. [PMID: 10915237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Prenatal HIV prevention practices in a low seroprevalence state. AIDS EDUCATION AND PREVENTION : OFFICIAL PUBLICATION OF THE INTERNATIONAL SOCIETY FOR AIDS EDUCATION 2000; 12:252-262. [PMID: 10926128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The purpose of this study was to build understanding of prenatal HIV counseling and testing practices in low seroprevalence states. Responses from a 1998 population-based survey of Kentucky prenatal care providers (67% response; 312 analyzed) were compared with findings from patient focus groups. Sixty-two percent of clinicians said they routinely counsel prenatal patients with risk factors, but only 46% routinely counsel patients without risk factors. The proportions routinely offering HIV testing to patients with and without risk factors were 94% and 84%, respectively. Prenatal patients identified "fear of a positive test result" as the major barrier to test acceptance. This fear was fueled by lack of knowledge regarding the benefits of early detection. The study concludes that achieving universal prenatal HIV testing will require new strategies, such as the distribution of a standardized protocol, that address clinicians' concerns about "time burdens" without depriving patients of the opportunity to receive individualized counseling.
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Benchmarking organ procurement organizations: a national study. Health Serv Res 1999; 34:855-74; discussion 875-8. [PMID: 10536974 PMCID: PMC1089045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
OBJECTIVE An exploratory examination of the technical efficiency of organ procurement organizations (OPOs) relative to optimal patterns of production in the population of OPOs in the United States. DATA SOURCES A composite data set with the OPO as the unit of analysis, constructed from a 1995 national survey of OPOs (n = 64), plus secondary data from the Association of Organ Procurement Organizations and the United Network for Organ Sharing. STUDY DESIGN The study uses data envelopment analysis (DEA) to evaluate the technical efficiency of all OPOs. PRINCIPAL FINDINGS Overall, six of the 22 larger OPOs (27 percent) are classified as inefficient, while 23 of the 42 smaller OPOs (55 percent) are classified as inefficient. Efficient OPOs recover significantly more kidneys and extrarenal organs; have higher operating expenses; and have more referrals, donors, extrarenal transplants, and kidney transplants. The quantities of hospital development personnel and other personnel, and formalization of hospital development activities in both small and large OPOs, do not significantly differ. CONCLUSIONS Indications that larger OPOs are able to operate more efficiently relative to their peers suggest that smaller OPOs are more likely to benefit from technical assistance. More detailed information on the activities of OPO staff would help pinpoint activities that can increase OPO efficiency and referrals, and potentially improve outcomes for large numbers of patients awaiting transplants.
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Abstract
Despite the rapid growth of AIDS cases in nonmetropolitan areas, little is known about the characteristics and needs of HIV-positive rural residents or how rural areas are responding to the epidemic. This paper proposes a typology for distinguishing among rural environments and examining variations in HIV service networks. The typology identifies three dimensions that have a major effect on the development of rural HIV service networks: degree of rurality, the prevalence of AIDS, and the epidemiological and demographic characteristics of the infected populations. Data from four case studies are used to illustrate how variations in rural environments can affect the organization and delivery of HIV/AIDS care. The typology contributes to public policy discussions by identifying key attributes of rural environments that influence program planning and implementation and the transferability of service delivery models.
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Abstract
Despite the fact that one of every 16 women with AIDS in the United States lives in a rural area, little is known about their demographic and epidemiologic characteristics, service needs, social support networks, or service utilization patterns. This article reports key findings from case studies of services to rural women with HIV/AIDS in southwest Georgia, northwest Mississippi, southeastern South Carolina, south Texas, and south-central Washington. Despite the growing numbers of HIV-positive women in these areas, many primary care physicians lack training in the diagnosis and treatment of HIV infection in women, and multidisciplinary protocols for the "shared care" of HIV-positive pregnant women are still being developed. Concerns about confidentiality and the lack of health insurance and transportation pose major access barriers. The findings suggest a need for new kinds of rural initiatives that embed HIV prevention and care into broader programs of educational and economic development.
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Hospital development and the performance of organ procurement organizations. JOURNAL OF TRANSPLANT COORDINATION : OFFICIAL PUBLICATION OF THE NORTH AMERICAN TRANSPLANT COORDINATORS ORGANIZATION (NATCO) 1998; 8:74-80. [PMID: 9727099 DOI: 10.7182/prtr.1.8.2.b62721h727814443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
With more than 56,000 patients on the national waiting list for organ transplants and relatively little growth in the number of donors, organ procurement organizations now recognize the need to aggressively market their services and the range of donor procurement opportunities to hospital personnel. This study examines the types and levels of hospital development activities being conducted by organ procurement organizations, the characteristics of organ procurement organizations that are more involved in hospital development, and the relationship between hospital development and organ procurement. Results from a national survey indicate that, as of the mid-1990s, organ procurement organizations had not made major investments in hospital development despite an increased recognition of the importance of these activities. Organ procurement organizations whose directors were more committed to hospital development exhibited higher levels of hospital development activity. Efforts to formalize hospital development activities through the establishment of a hospital development department and evaluation standards were associated with more organs procured per donor.
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Abstract
Integrated delivery systems that promote learning and flexibility will be better prepared to face the challenges imposed by a complex and competitive environment. The integration of learning into these systems requires a shared vision, facilitative leadership, and highly functioning communication channels within an organic structure. Strategies that promote positive attitudes toward change are necessary for learning as is the provision of resources, training, incentives, and rewards that support learning, and feedback on how new administrative and clinical practices advance the mission and goals of the system.
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Abstract
The complex and varied needs of people with HIV/AIDS have prompted major changes in the way that health care is organized and delivered. In the USA, the Netherlands and the UK, many HIV service providers have formed alliances to better coordinate policies and programs. These structural reforms have been accompanied by extensive reforms in the financing of health services. Drawing upon case studies of seven HIV/AIDS alliances in the Netherlands and the UK, the article examines how alliances are adapting their missions, organizational structures and functions to be responsive to changing community attitudes and the gradual elimination of earmarked HIV/AIDS funding. The case studies suggest strategies for maintaining interorganizational cooperation around public health issues in unstable and competitive funding environments.
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Interorganizational exchanges as performance markers in a community cancer network. Health Serv Res 1993; 28:459-78. [PMID: 8407338 PMCID: PMC1069952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
OBJECTIVE This study examines how "strategic partnerships" between community-based consortia of oncologists and hospitals (CCOPs) and clinical cooperative groups emerge, develop, and influence patient accruals (i.e., the number of patients enrolled in clinical trials) over time. DATA SOURCES AND STUDY SETTING Study analyses are based on 65 pairwise relationships that 38 CCOPs established with eight clinical cooperative groups in September 1983 and maintained through February 1989. Data are drawn from grantee applications and progress reports. STUDY DESIGN The study examines how different types of CCOP-cooperative group exchange relate to one another and to CCOP patient accruals over six time points. Key independent variables include resource dependence, information exchange (i.e., meeting attendance and committee membership), and protocol exchange (i.e., the number of different protocols used). DATA COLLECTION METHODS Data extracted from secondary sources were entered in a data base. PRINCIPAL FINDINGS The number of CCOP physicians and support staff who attend cooperative group meetings during the first two years of a clinical research partnership has a significant influence on meeting attendance and protocol use in later years. Two-thirds or more of the variance in patient accruals at each time point can be explained by the number of different protocols used and the number of CCOP representatives serving on cooperative group committees (or attending cooperative group meetings). CONCLUSIONS The findings highlight the importance of historical relationships and anticipated resource dependence in shaping initial exchange patterns. They also suggest that strategic partnerships need to emphasize structures and processes that encourage early involvement in collaborative activities and that reward participants for maintaining high levels of interaction.
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States' responses to Title II of the Ryan White CARE Act. Public Health Rep 1993; 108:4-11. [PMID: 8434096 PMCID: PMC1403324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Title II of the Ryan White Comprehensive AIDS Resources Emergency (CARE) Act of 1990 provides formula-based grants to States to help them improve the quality, availability, and organization of health care and support services for people with human immunodeficiency virus (HIV) infection. This article reviews State expenditures during the first year of CARE Act funding (April 1991-March 1992) within the context of Title II guidelines and the federally funded grant programs that preceded and helped shape Title II. The authors also discuss future challenges that require development of resources, the assessment of program impact, and the evaluation of the quality and appropriateness of HIV-related services. Ninety-one percent of the $77.5 million awarded to States during fiscal year 1991 went for the provision of medical and support services through HIV care consortia, drug reimbursement programs, home and community-based care programs, and health insurance initiatives. The remaining monies were used for planning, evaluation, and program administration. Forty States allocated $38.9 million for the establishment of HIV care consortia to assess service needs and to develop comprehensive continuums of health and support services in the areas most affected by HIV disease. Fifty States allocated an additional $28.3 million for the continuation or expansion of FDA-approved drug therapies for low-income people with HIV infection. Twenty-five States allocated $2.2 million for the provision of home- and community-based health services, and 16 States allocated $1.3 million for programs that help low-income people with HIV infection to purchase or maintain health insurance coverage.
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Abstract
Although numerous studies have established that breast cancer mortality can be significantly reduced through early detection, only a small percentage of women obtain screening mammograms at intervals recommended by the National Cancer Institute, the American Cancer Society, and other major medical organizations. This paper examines the importance of cost as a barrier to routine screening and the state legislative movement to make screening mammography a basic health insurance benefit. Mammography "knowledge, attitudes, and behavior" studies offer conflicting findings on the extent to which cost enters into the decision to have a mammogram. Women seldom report cost as a major reason for postponing or failing to have a mammogram; yet, descriptive studies show a consistently positive relationship between income and mammography use. State mammography reimbursement laws vary greatly with respect to whether screening mammography is a required or optional benefit, payment limits, and eligibility and referral requirements. Although state-specific data on the percentage of women with private health insurance are not available, 1987 National Medical Expenditure Survey estimates for U.S. Census geographic divisions suggest that the New England, East North Central, West North Central, Middle Atlantic, and Mountain states have the highest percentages of women who are privately-insured and, thus, potentially eligible for legislated mammography benefits. Access to screening mammography also is likely to be influenced by the proportion of employer-sponsored health plans that are self-insured and, therefore, exempt from minimum benefit mandates and the extent to which women are aware of the screening coverage.
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Synthesis and in vitro characterization of novel amino terminally modified oxotremorine derivatives for brain muscarinic receptors. J Med Chem 1992; 35:1550-7. [PMID: 1578480 DOI: 10.1021/jm00087a008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A series of novel 2-substituted acetylenic pyrrolidines and piperidines related to oxotremorine (1) were prepared and evaluated in vitro as muscarinic cholinergic agents at brain M1 and M2 receptors. One analogue, 3-(2-oxo-1-pyrrolidinyl)-1-[2(R)-pyrrolidinyl]-1-propyne hydrogen oxalate (6a), was found to be a partial agonist producing a PI hydrolysis response at cortical M1 receptors approximately 3-fold larger than that produced by 1. The intrinsic activity profile of 6a at brain muscarinic receptors is similar to those of azetidine oxo analogue 2 and dimethylamino oxo analogue. All three compounds are partial M1 agonists and full M2 agonists; however, the profile of 6a in binding studies is significantly different. While 2 and 3 exhibit large M2 selectivities ranging between 8-fold to several hundred-fold, the binding profile of 6a shows almost no subtype selectivity.
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Organizing for cancer control. The diffusion of a dynamic innovation in a community cancer network. Int J Technol Assess Health Care 1992; 8:268-88. [PMID: 1628909 DOI: 10.1017/s0266462300013490] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper examines the diffusion of a "dynamic" innovation--research on the prevention and control of cancer--in a community cancer network. By analyzing the social structures and communication strategies of network members, as well as the attributes of the innovation, the authors explain why this innovation is diffusing more slowly than its "formed" counterpart--research on the treatment of cancer.
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Paths and pacemakers: innovation diffusion networks in multihospital systems and alliances. Health Care Manage Rev 1991; 16:17-23. [PMID: 2004907 DOI: 10.1097/00004010-199101610-00004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This article examines the role of multihospital systems and alliances as "innovation carriers." Drawing upon studies of interpersonal and interorganizational communications networks, the authors suggest how membership in a system or alliance, as well as network characteristics, affects innovation practices in general acute care hospitals.
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Abstract
A simple, two-step procedure to purify the immunoglobulin G (IgG) fraction from mammalian sera and ascites fluid is described. In the first step, albumin and other non-IgG proteins are precipitated with caprylic acid (octanoic acid). In the second, the IgG fraction is precipitated with ammonium sulfate. Factors influencing the precipitation of serum proteins by caprylic acid are described, as are procedural modifications to purify the IgG fraction from sera with a high lipid content. The procedure can be used to purify the IgG fraction of serum from rabbit, sheep, goat, horse, rat and mouse, as well as monoclonal antibodies from mouse ascites fluid. Greater than 80% of the IgG in rabbit serum could be isolated by this procedure, with a purity equal to rabbit IgG purified by anion-exchange chromatography. In addition to its simplicity and low cost, the procedure described offers several advantages over other methods to purify IgG.
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Digitoxin metabolism by liver microsomal cytochrome P-450 and UDP-glucuronosyltransferase and its role in the protection of rats from digitoxin toxicity by pregnenolone-16 alpha-carbonitrile. Arch Biochem Biophys 1986; 251:188-97. [PMID: 3098175 DOI: 10.1016/0003-9861(86)90065-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The aim of the present study was to investigate whether the mechanism by which pregnenolone-16 alpha-carbonitrile (PCN) protects rats from digitoxin toxicity was dependent on the induction of liver microsomal cytochrome P-450p and/or the UDP-glucuronosyltransferase active toward digitoxigenin monodigitoxoside (UDP-GT-dt1). Evidence is presented that suggests troleandomycin is a selective inhibitor of cytochrome P-450p in vivo, based on the pattern of inhibition observed when zoxazolamine paralysis time and hexobarbital sleeping time were measured in rats treated with different cytochrome P-450 inducers. A single dose of troleandomycin completely reversed the ability of PCN to protect rats from digitoxin toxicity, establishing the importance of cytochrome P-450p induction in the protective effect of PCN. The postpubertal decline in constitutive cytochrome P-450p levels in female but not male rats was paralleled by a female-specific, age-dependent decline in the rate of digitoxin sugar cleavage (i.e., digitoxosyl oxidation of digitoxin to 15'-dehydrodigitoxin and digitoxosyl cleavage to digitoxigenin bisdigitoxoside). This resulted in a marked sex difference in the rate of digitoxin sugar cleavage catalyzed by liver microsomes from mature rats (male/female approximately 6). However, no sex difference in digitoxin toxicity was observed in either immature or mature rats. In contrast to cytochrome P-450p, liver microsomal UDP-GT-dt1 activity increased dramatically with age in both male and female rats (mature/immature approximately 10). However, no age differences in digitoxin toxicity were observed in rats of either sex. The results indicate that cytochrome P-450p and UDP-GT-dt1 can be independently regulated in rat liver and that large changes in the constitutive levels of these microsomal enzymes have no effect on digitoxin toxicity. This suggests that the induction of cytochrome P-450p and UDP-GT-dt1 does not fully account for the mechanism by which PCN protects rats from digitoxin toxicity.
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Stimulation of arachidonic acid release and eicosanoid biosynthesis in an interleukin 2-dependent T cell line. JOURNAL OF IMMUNOPHARMACOLOGY 1986; 8:165-204. [PMID: 3088127 DOI: 10.3109/08923978609028614] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Previous studies have provided pharmacologic evidence that T lymphocyte function may be regulated in part by the intracellular production of various arachidonic acid (AA) metabolites in response to cellular stimulation. However, the specific AA metabolic capabilities of homogeneous T cell populations have not been clearly defined. In the present studies, we have employed an accessory cell-free T cell line, HT-2, as a model system for the examination of stimulus-induced eicosanoid biosynthesis in T lymphocytes. HT-2 cells were biosynthetically labeled with [3H]-AA and challenged briefly with various agents that stimulate the hydrolytic release of AA from cellular phospholipids. The bee venom peptide melittin stimulated a profound AA release response in the cells and the concomitant synthesis of both cyclooxygenase (PGF2 alpha, PGE2 and PGD2) and lipoxygenase (5-,12-,15-HETE and possibly 5-,12-diHETE) metabolites of AA. The formation of PGs was blocked by 5 microM indomethacin, demonstrating that this cell line contains cyclooxygenase activity functionally similar to that described in macrophages and other cell types. The high activity of melittin in this system was shown to result largely from a synergy between the peptide itself and a persistent bee venom phospholipase A2 contaminant. However, experiments with melittin freed of detectable phospholipase A2 activity by heating, and with synthetic homopolymers of (L)-lysine and (L)-arginine demonstrated that HT-2 cells contain sufficient endogenous, stimulus-responsive phospholipase A2 to provide both the cyclooxygenase and lipoxygenase pathways of AA metabolism ith substrate. In contrast, Ca++ ionophores, which are known to stimulate AA release and metabolism in certain cell types, stimulated only AA release but no detectable eicosanoid biosynthesis in HT-2 cells. Experiments with exogenous bacterial phospholipase C suggested that this cell line can also generate free AA for eicosanoid biosynthesis from membrane-derived 1,2-diacylglycerol. These results indicate that multiple intracellular pathways of AA metabolism are present HT-2 cells, and that the stimulus-induced release of AA and the production of eicosanoid second messengers may result from activation of either phospholipase A2 or phospholipase C.
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The newest miracle drug: quality circles in hospitals. HOSPITAL & HEALTH SERVICES ADMINISTRATION 1984; 29:74-87. [PMID: 10268654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
In recent years, a number of hospitals throughout the United States have been exploring the use of Japanese-style quality circles to reduce their operating expenses, improve productivity, and enhance the quality of work life for hospital employees. This article examines the organizational climate necessary for quality circles, methods used to implement quality circles, and management's role in guiding and responding to circle activities. Ideas for building and maintaining staff support are presented along with a cost/benefit analysis of quality circle programs. The author concludes that quality circles are most successful in hospitals where they are part of a larger organizational development effort. When administrators believe in their employees' ability to contribute to the institution and are willing to invest necessary time and resources in employee education and the measurement of quality circle achievements, quality circles can produce creative solutions to perplexing institutional problems.
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