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1.
J Antimicrob Chemother ; 67(8): 2005-12, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22556381

RESUMEN

OBJECTIVES: Systemic aciclovir and its prodrug valaciclovir are effective in treating and reducing recurrences of genital herpes simplex virus (HSV) and reducing transmission. Local aciclovir delivery, if it can achieve and maintain comparable intracellular genital tract levels, may be equally effective in the treatment and suppression of genital HSV. Intravaginal ring (IVR) delivery of aciclovir may provide pre-exposure prophylaxis against HSV acquisition. METHODS: Tolerability and pharmacokinetics were evaluated in six HIV-negative women with recurrent genital HSV who switched their daily oral valaciclovir suppression to an aciclovir IVR for 7 days (n = 3) or 14 days (n = 3). Blood and cervicovaginal lavage (CVL) were collected after oral and IVR dosing to measure aciclovir concentrations and genital swabs were obtained to quantify HSV shedding by PCR. RESULTS: The rings were well tolerated. Median plasma aciclovir concentrations were 110.2 ng/mL (IQR, 85.9-233.5) 12-18 h after oral valaciclovir. Little or no drug was detected in plasma following IVR dosing. Median (IQR) CVL aciclovir levels were 127.3 ng/mL (21-660.8) 2 h after oral valaciclovir, 154.4 ng/mL (60.7-327.5) 12-18 h after oral valaciclovir and 438 ng/mL (178.5-618.5) after 7 days and 393 ng/mL (31.6-1615) after 14 days of aciclovir ring use. Median CVL aciclovir levels 2 h after oral dosing were similar to levels observed 7 (P = 0.99) and 14 (P = 0.75) days after ring use. HSV DNA was not detected in genital swabs and there was no significant change in inflammatory mediators. CONCLUSIONS: This first-in-human study demonstrated that an IVR could safely deliver mucosal levels of aciclovir similar to oral valaciclovir without systemic absorption. More intensive site-specific pharmacokinetic studies are needed to determine whether higher local concentrations are needed to achieve optimal drug distribution within the genital tract.


Asunto(s)
Aciclovir/farmacocinética , Antivirales/farmacocinética , Dispositivos Anticonceptivos Femeninos/efectos adversos , Portadores de Fármacos/administración & dosificación , Herpes Genital/tratamiento farmacológico , Herpes Genital/prevención & control , Elastómeros de Silicona/administración & dosificación , Aciclovir/administración & dosificación , Aciclovir/efectos adversos , Adulto , Antivirales/administración & dosificación , Antivirales/efectos adversos , Portadores de Fármacos/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Membrana Mucosa/química , Plasma/química , Elastómeros de Silicona/efectos adversos , Vagina/química
2.
Osteoporos Int ; 19(7): 913-8, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18071649

RESUMEN

UNLABELLED: Most studies of bone density in HIV-infected individuals focus on young men. This study compares differences in bone density in elderly HIV positive men and women to HIV negative controls. Bone density was lower in the lumbar spine and hip in the HIV-infected group. Antiretrovirals may be associated with decreased bone mineralization. INTRODUCTION: Individuals with human immunodeficiency virus (HIV) may be at increased risk for osteoporosis. Prolonged exposures to HIV and/or antiretroviral therapy are possible causes for this association. This study compares differences in bone mineral density (BMD) in elderly HIV positive men and women to HIV negative controls. METHODS: A cross-sectional study was conducted among 57 HIV-infected and 47 HIV negative subjects over age 55. BMD at the lumbar spine and total hip and markers of bone turnover were compared. RESULTS: BMD was borderline lower in the lumbar spine and significantly lower in the hip in the HIV-infected group. Controlling for age, sex, race and body mass index, differences between the groups were significant at both sites. There was no difference in markers of bone turnover between the groups. Tenofovir use was significantly associated with decreased BMD at the spine while protease inhibitor use was significantly associated with decreased BMD at the hip. CONCLUSION: Elderly men and women with HIV have lower bone mass than HIV negative controls. Decreased body mass index was the most important risk factor associated with decreased BMD. Bone demineralization was observed among HIV-infected subjects receiving either tenofovir or a protease inhibitor.


Asunto(s)
Densidad Ósea/fisiología , Huesos/fisiología , Infecciones por VIH/complicaciones , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Seronegatividad para VIH/fisiología , Cadera/fisiología , Humanos , Vértebras Lumbares/fisiología , Masculino , Persona de Mediana Edad , Factores de Riesgo
3.
Am J Transplant ; 8(2): 355-65, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18093266

RESUMEN

Improvements in human immunodeficiency virus (HIV)-associated mortality make it difficult to deny transplantation based upon futility. Outcomes in the current management era are unknown. This is a prospective series of liver or kidney transplant recipients with stable HIV disease. Eleven liver and 18 kidney transplant recipients were followed for a median of 3.4 years (IQR [interquartile range] 2.9-4.9). One- and 3-year liver recipients' survival was 91% and 64%, respectively; kidney recipients' survival was 94%. One- and 3-year liver graft survival was 82% and 64%, respectively; kidney graft survival was 83%. Kidney patient and graft survival were similar to the general transplant population, while liver survival was similar to the older population, based on 1999-2004 transplants in the national database. CD4+ T-cell counts and HIV RNA levels were stable; and there were two opportunistic infections (OI). The 1- and 3-year cumulative incidence (95% confidence intervals [CI]) of rejection episodes for kidney recipients was 52% (28-75%) and 70% (48-92%), respectively. Two-thirds of hepatitis C virus (HCV)-infected patients, but no patient with hepatitis B virus (HBV) infection, recurred. Good transplant and HIV-related outcomes among kidney transplant recipients, and reasonable outcomes among liver recipients suggest that transplantation is an option for selected HIV-infected patients cared for at centers with adequate expertise.


Asunto(s)
Infecciones por VIH/complicaciones , Trasplante de Riñón/estadística & datos numéricos , Trasplante de Hígado/estadística & datos numéricos , Adulto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Cadáver , Femenino , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Infecciones por VIH/tratamiento farmacológico , Humanos , Trasplante de Riñón/inmunología , Trasplante de Hígado/inmunología , Donadores Vivos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Donantes de Tejidos/estadística & datos numéricos , Resultado del Tratamiento , Carga Viral
5.
Am J Reprod Immunol ; 49(5): 279-84, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12854732

RESUMEN

Topical microbicides, designed for vaginal or rectal administration, are needed to prevent human immunodeficiency virus (HIV) and other sexually transmitted infections (STI). Presently marketed topical microbicides are cytotoxic and damage the vaginal epithelium with frequent use. Rational development of new candidate compounds should build on knowledge of the pathways of microbial invasion. The establishment of assays and models that predict efficacy and safety is critical. Comprehensive pre-clinical evaluation of promising microbicides should include rigorous assessment of the effects of repeated application of topical agents on mucosal inflammatory cells, cytokines, and the genital tract virus population. These studies will lay the groundwork for future clinical trials.


Asunto(s)
Antiinfecciosos Locales , Infecciones por VIH/prevención & control , VIH , Herpes Simple/prevención & control , Simplexvirus , VIH/fisiología , Humanos , Simplexvirus/fisiología
6.
J Virol ; 77(12): 6666-75, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12767986

RESUMEN

Prior studies have suggested a role of the five copies of the 19-bp-repeat cyclic AMP (cAMP)-response element (CRE) in major immediate-early (MIE) promoter activation, the rate-limiting step in human cytomegalovirus (HCMV) replication. We used two different HCMV genome modification strategies to test this hypothesis in acutely infected cells. We report the following: (i) the CREs do not govern basal levels of MIE promoter activity at a high or low multiplicity of infection (MOI) in human foreskin fibroblast (HFF)- or NTera2-derived neuronal cells; (ii) serum and virion components markedly increase MIE promoter-dependent transcription at a low multiplicity of infection (MOI), but this increase is not mediated by the CREs; (iii) forskolin stimulation of the cAMP signaling pathway induces a two- to threefold increase in MIE RNA levels in a CRE-specific manner at a low MOI in both HFF- and NTera2-derived neuronal cells; and (iv) the CREs do not regulate basal levels of HCMV DNA replication at a high or low MOI in HFF. Their presence does impart a forskolin-induced increase in viral DNA replication at a low MOI but only when basal levels of MIE promoter activity are experimentally diminished. In conclusion, the 19-bp-repeat CREs add to the robust MIE promoter activity that occurs in the acutely infected stimulated cells, although the CREs' greater role may be in other settings.


Asunto(s)
AMP Cíclico/metabolismo , Citomegalovirus/fisiología , Proteínas Inmediatas-Precoces/genética , Regiones Promotoras Genéticas , Elementos de Respuesta/genética , Activación Viral , Emparejamiento Base , Línea Celular , Citomegalovirus/genética , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/virología , Regulación Viral de la Expresión Génica , Humanos , Mutación , Secuencias Repetitivas de Ácidos Nucleicos , Transcripción Genética , Replicación Viral
7.
Proc Biol Sci ; 268(1465): 341-5, 2001 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-11270429

RESUMEN

Whole-genome duplication is believed to have played a significant role in the early evolution and diversification of vertebrate animals. The establishment of newly arisen polyploid lineages of sexually reproducing animals requires assortative mating between polyploids. Here, we show that genome duplication can directly alter a phenotypic trait mediating mate choice in the absence of genotypic change. Our results suggest that the direct effect of polyploidy on behaviour is a consequence of increased cell size.


Asunto(s)
Anuros/genética , Poliploidía , Conducta Sexual Animal , Animales , Anuros/fisiología , Núcleo Celular , Eritrocitos , Femenino , Masculino , Temperatura
8.
Clin Infect Dis ; 32(1): 140-3, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11118393

RESUMEN

To assess a possible association between antiretroviral treatment and paronychia, we conducted a retrospective cohort study of 288 human immunodeficiency virus-positive protease inhibitor recipients. Indinavir treatment-adjusted for age, sex, CD4 count, diabetes status and other antiretroviral drug exposures-was significantly associated with paronychia of the great toe (hazard ratio 4.7; 95% confidence interval 1.6-13.9).


Asunto(s)
Infecciones por VIH/complicaciones , Inhibidores de la Proteasa del VIH/efectos adversos , VIH-1 , Indinavir/efectos adversos , Paroniquia/inducido químicamente , Adulto , Anciano , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Inhibidores de la Proteasa del VIH/uso terapéutico , Humanos , Indinavir/uso terapéutico , Masculino , Persona de Mediana Edad , Paroniquia/complicaciones , Estudios Retrospectivos , Carga Viral
9.
Aging (Milano) ; 11(1): 35-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10337440

RESUMEN

To better understand disease progression in older persons with human immunodeficiency virus (HIV infection or acquired immunodeficiency syndrome (AIDS), we studied patients aged 50 years and older hospitalized with a diagnosis of HIV infection or AIDS between January 1985 and October 1995. Data collected included demographics, opportunistic infections, comorbid disease, neurologic dysfunction, and antiretroviral therapy. A total of 86 patients with a mean age of 54.3 years was identified. Pneumocystis carinii pneumonia was the most frequent opportunistic infection (43%). Hypertension was the most common previous medical condition (38%). Other comorbid disease was present in less than 15% of the subjects. Fifty-seven patients (66%) had neurologic impairment, with 30 requiring treatment for delirium. In these 30, 23 (77%) had anemia, infection, or both. The median length of survival following the diagnosis of AIDS was 18.5 months, for HIV it was 48 months. The median survival following the diagnosis of AIDS in patients who received antiretroviral therapy was 22 months compared with 11 months for those who did not receive antiretroviral therapy (p < 0.0004). Multivariable analysis found that antiretroviral therapy was the only independent predictor of survival after the diagnosis of AIDS. In contrast to previous studies, the present findings suggest that older age may not necessarily be associated with more rapid disease progression and reduced survival times in persons with HIV infection or AIDS. In those patients with delirium, many may have readily treatable conditions (anemia and/or infection). The absence of significant comorbid disease and the access to antiretroviral therapy may be in part responsible for the longer survival times obtained in this cohort compared to that reported previously.


Asunto(s)
Infecciones por VIH/fisiopatología , Envejecimiento/fisiología , Anemia/etiología , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Caracteres Sexuales , Análisis de Supervivencia
10.
AIDS ; 12(18): 2433-7, 1998 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-9875581

RESUMEN

BACKGROUND: Nephrolithiasis may be an important consequence of indinavir therapy; however little has been published on the variation in incidence between different populations of patients or the possible mechanisms of calculus formation. OBJECTIVE: To examine variation in the incidence of indinavir-associated nephrolithiasis (IAN) in HIV-positive patients in relation to hemophilia and hepatitis C virus (HCV) infection. METHODS: Clinical data were abstracted retrospectively from the medical records of all adult patients treated with indinavir from September 1995 to September 1997. Occurrence of first IAN, defined as flank pain and hematuria after initiation of therapy, was analyzed in relation to hemophilia status and HCV infection. RESULTS: There were 17 episodes of IAN (22%) among 79 patients treated with indinavir. Of 10 patients with hemophilia, 50% developed IAN as compared with 17% of patients without hemophilia (P = 0.03). Median days to first IAN was 22 (range 7-110 days) for hemophiliacs and 156 (range 5-611 days) for those without hemophilia. Data for HCV status were available for 74 out of 79 patients: 10 out of 27 (37%) patients with HCV developed IAN compared with six out of 42 (14%) without HCV (P = 0.02). CONCLUSION: Overall incidence of IAN was higher than that previously reported and was significantly greater in hemophiliacs than in non-hemophiliacs. HCV may be a contributing factor.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/efectos adversos , Indinavir/efectos adversos , Cálculos Renales/inducido químicamente , Adulto , Femenino , Infecciones por VIH/complicaciones , Hemofilia A/complicaciones , Hepatitis C/complicaciones , Humanos , Incidencia , Cálculos Renales/epidemiología , Masculino , Factores de Riesgo
11.
AIDS Clin Care ; 9(12): 94, 100, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11364841

RESUMEN

AIDS: A case report of two HIV-infected men diagnosed with aspergillus sinusitis is provided. Despite aggressive treatment with antifungal agents, such as amphotericin B and itraconazole, the sinusitis would not resolve. Both protease inhibitor-naive patients were treated with the same antiretroviral regimen. Only one of the patients had a dramatic drop in viral load; the other patient succumbed to neurologic deficits and respiratory failure. Many patients who are using protease inhibitors continue to have good clinical status despite rising viral loads. The availability of antiretroviral therapy has changed the outlook for opportunistic infections, such as severe intestinal cryptosporidiosis, PML, and azole-resistant oral candidiasis. The key role in recovery is successful treatment with antiretroviral therapy to enable the body to fight such infections.^ieng


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Itraconazol/uso terapéutico , Sinusitis/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Infecciones Oportunistas Relacionadas con el SIDA/patología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Adulto , Fármacos Anti-VIH/uso terapéutico , Aspergilosis/complicaciones , Aspergilosis/patología , Aspergillus fumigatus/aislamiento & purificación , Recuento de Linfocito CD4 , Humanos , Masculino , Persona de Mediana Edad , Sinusitis/complicaciones , Sinusitis/patología , Resultado del Tratamiento , Carga Viral
13.
J Biol Chem ; 263(25): 12346-51, 1988 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-3045116

RESUMEN

We have identified two chromatographically separable forms of mitochondrial RNA polymerase from Saccharomyces cerevisiae which utilize different DNA templates. One form is only active in a nonselective assay utilizing a poly[d(A-T)] template. The other form selectively initiates from a mitochondrial promoter consensus sequence. Both enzymes can be extracted from yeast mitochondria and all components are encoded by nuclear genes. The possibility that these two activities represent core and holoenzyme forms of the multicomponent mitochondrial RNA polymerase is supported by our observation that both enzymes are absent from a strain bearing a disrupted copy of the RPO41 gene (Greenleaf, A. L., Kelly, J. L., and Lehman, I. R. (1986) Proc. Natl. Acad. Sci. U. S. A. 83, 3391-3399). The two enzyme activities are differentially regulated by carbon source; the nonselective enzyme is repressed during growth on glucose relative to the selective enzyme. The 5-fold increase in RNA polymerase activity on a nonrepressing carbon source correlates with the increased level of transcript production from mitochondrial DNA. These results suggest that the mitochondrial RNA polymerase and, in consequence, mitochondrial transcription are regulated by carbon catabolite control.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/genética , Regulación de la Expresión Génica/efectos de los fármacos , Genes Fúngicos , Glucosa/farmacología , Mitocondrias/enzimología , Saccharomyces cerevisiae/enzimología , Cromatografía , ADN Mitocondrial/genética , ARN Polimerasas Dirigidas por ADN/aislamiento & purificación , Mutación , Poli dA-dT/metabolismo , Cloruro de Potasio , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/genética , Transcripción Genética
14.
DNA ; 7(1): 47-55, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3349904

RESUMEN

A HeLa cell nuclear transcription extract that is approximately 20 times more efficient than standard HeLa cell transcription extracts was developed. Transcription of the strong adenovirus II major late promoter by this extract results in the synthesis of 1.5-4 molecules of product RNA per molecule of template, indicating that the extract is capable of multiple rounds of initiation. Standard HeLa cell nuclear extracts transcribe closed circular and linear adenovirus major late promoter templates with equal efficiency. In contrast, the new extract exhibits an increase of approximately twofold on transcription of a closed circular, as opposed to a linear, major late promoter template.


Asunto(s)
Células HeLa/metabolismo , Transcripción Genética , Adenoviridae/genética , Animales , Núcleo Celular/metabolismo , Sistema Libre de Células , Humanos , Regiones Promotoras Genéticas , Vitelogeninas/genética , Xenopus/genética
15.
Ther Recreation J ; 22(3): 12-22, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-10304252

RESUMEN

This article describes the implications of the AIDS epidemic for therapeutic recreation practitioners in various settings. The AIDS disease spectrum, its epidemiology, transmission, and health effects are discussed in light of the attitudes, education, policy, and program issues that therapeutic recreation practitioners will confront in working with clients and staff in settings that are attempting to deal with the AIDS epidemic. Most health care professions will be challenged to address what has been viewed as history's greatest natural tragedy. Yet, only those professions which seek answers to defining and accepting their roles in dealing with the AIDS epidemic will contribute to the quality of life for persons with AIDS.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Técnicos Medios en Salud , Recreación , Terapéutica , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Síndrome de Inmunodeficiencia Adquirida/prevención & control , Actitud del Personal de Salud , Ética Profesional , Humanos , Estados Unidos/epidemiología
16.
J Biol Chem ; 262(11): 4939-42, 1987 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-3558378

RESUMEN

We have isolated and sequenced a full-length cDNA cloned tentatively identified as encoding Xenopus laevis serum retinol-binding protein (RBP) mRNA. The derived amino acid sequence of the Xenopus protein is 63% homologous to the sequence of the human RBP. 17 of 19 amino acids identified as critical in the retinol-binding pocket of human RBP are identical or conservative replacements in the Xenopus protein. The RBP cDNA clone has been used as a hybridization probe to demonstrate that administration of estradiol-17 beta to male X. laevis induces hepatic RBP mRNA 10-fold from its constitutive in vivo level of 1,800 molecules/cell to approximately 18,000 molecules/cell. Using a simplified method for determining relative rates of gene transcription, we demonstrate an estrogen-mediated increase in the rate of RBP gene transcription. These quantitative data provide the first demonstration that a steroid hormone regulates the levels of vertebrate retinol-binding protein mRNA.


Asunto(s)
Estrógenos/farmacología , Proteínas de Unión al Retinol/genética , Transcripción Genética/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN/análisis , Humanos , Hibridación de Ácido Nucleico , ARN Mensajero/biosíntesis , Xenopus laevis
17.
J Biol Chem ; 260(26): 14214-23, 1985 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-3902826

RESUMEN

Using a whole cell extract from Saccharomyces cerevisiae (bakers' yeast) we have been able to detect a selective RNA polymerase activity originally identified in purified yeast mitochondria (Levens, D., Morimoto, R., and Rabinowitz, M. (1981) J. Biol. Chem. 256, 1466-1473). We have shown that in in vitro transcription reactions this activity recognizes a consensus mitochondrial promoter sequence ATA-TAAGTA (Osinga, K. A., DeHaan, M., Christianson, T., and Tabak, H. F. (1982) Nucleic Acids Res. 10, 7993-8006) in the upstream region of the nuclear GAL10 gene as well as promoters from yeast mitochondrial DNA. Using these promoter-containing templates for in vitro assays, we have chromatographically separated the mitochondrial specific RNA polymerase activity from the three nuclear RNA polymerases (I, II, and III). Further characterization has revealed that this preparation has distinctive properties on two different types of DNA templates, poly[d(AT)] and cloned DNA containing mitochondrial promoters. Salt and divalent cation optima and substrate saturation kinetics are different for the two types of templates. Using promoter-containing DNA as an assay template, we have chromatographically dissociated the RNA polymerase activity into two nonfunctional components. Selective transcription of the GAL10 template is restored when the two components are recombined. It is possible that the RNA polymerase active on poly[d(AT)] is a nonspecific component of the selective transcription apparatus or that two distinct RNA polymerases are present in the preparation.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/metabolismo , Mitocondrias/enzimología , Saccharomyces cerevisiae/enzimología , Transcripción Genética , Secuencia de Bases , Núcleo Celular/enzimología , ADN de Hongos/genética , ADN Recombinante , ARN Polimerasas Dirigidas por ADN/aislamiento & purificación , Galactosa/genética , Genes Fúngicos , Cinética , Magnesio/farmacología , Manganeso/farmacología , Poli dA-dT/genética , Regiones Promotoras Genéticas , Moldes Genéticos
18.
Endocrinology ; 116(6): 2438-49, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2986951

RESUMEN

The mechanism whereby thyroid hormones modulate the transport properties of luminal brush border membrane (BBM) of renal proximal tubules was studied in thyroparathyroidectomized rats. Administration of both T4 and T3 increased BBM capacity for Na+ gradient-dependent uptake of phosphate (Pi) by BBM vesicles (BBMV). This effect of thyroid hormones was present in thyroparathyroidectomized and hypophysectomized rats, and it was not blocked by a saturating dose of propranolol. The stimulatory effect of T3 and T4 on BBM transport of Pi was dose dependent in the range of 5.2-520 nmol/100 g BW. Pretreatment of rats with inhibitors of 5'-monodeiodinase (5'-DI), iopanoic acid or ipodate, prevented the increase in serum T3 in rats injected with T4, but it did not diminish the increase in BBM transport of Pi. Administration of iopanoic acid and ipodate also prevented a 5-fold increase in 5'-DI activity in renal cortical tissue elicited by T4 administration. Treatment with T3 resulted in an increase of Pi transport across BBM from kidneys of rats subjected to dietary Pi deprivation due either to total fasting or to feeding of a low Pi diet. Further, T3 administration enhanced amiloride-sensitive Na+-H+ countertransport across BBM, but the uptake of 22Na+ by BBMV in the absence of pH gradient was not changed. The Na+ gradient-dependent uptake of L-[3H]proline by BBMV was slightly decreased, but the uptake of [14C]citrate was not changed in response to T3. Administration of T3 increased Pi transport in BBMV prepared from juxtamedullary cortex, but not in BBMV from superficial cortex. Conversely, the rate of Na+-H+ countertransport was enhanced, and the enzymatic activity of alkaline phosphatase was decreased in BBMV from superficial cortex; no changes in these parameters were found in BBMV from juxtamedullary cortex. Our results indicate that the stimulatory effect of administered T3 and/or T4 on renal BBM transport of Pi is distinct from the modulatory effect of dietary Pi intake and is not secondary to the beta-effect of catecholamines or to altered secretion of GH. Both T3 and T4 elicit the increase in BBM transport of Pi in a similar manner; T4 is effective even after profound inhibition of in vivo conversion of T4 to T3 by potent 5'-DI inhibitors. Administration of T3 stimulates Na+ gradient-dependent Pi uptake only in BBMV prepared from the juxtamedullary zone, and it stimulates the H+-Na+ countertransport only in BBMV from the outer cortical zone. These findings indicate that thyroid hormones modulate the two distinct transport functions of BBM derived from two different populations of renal proximal tubules.


Asunto(s)
Corteza Renal/metabolismo , Fosfatos/metabolismo , Hormonas Tiroideas/farmacología , Animales , Transporte Biológico/efectos de los fármacos , Hipofisectomía , Ácido Yopanoico/farmacología , Ipodato/farmacología , Corteza Renal/efectos de los fármacos , Masculino , Microvellosidades/metabolismo , Glándulas Paratiroides/cirugía , Prolina/metabolismo , Propranolol/farmacología , Protones , Ratas , Ratas Endogámicas , Sodio/metabolismo
19.
Ther Recreation J ; 19(1): 36-43, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-10271684

RESUMEN

It is the role of management in therapeutic recreation to create a working environment where personnel can accomplish their duties; create and maintain relationships; and work together harmoniously and creatively to obtain the organization's mission or purpose. This is an awesome job and therapeutic recreation managers are at times confronted with low-morale environments. Yet, there are strategies which can be employed to create positive working environments. Yet, there are strategies which can be employed to create positive working environments for therapeutic recreation personnel. These transformation techniques are: acknowledging negativity, identifying the positives, being available, providing positive recognition, avoiding negative game playing, refraining from negative conversation, avoiding putdowns, and using positive and effective communication. A successful therapeutic recreation supervisor can bring about positive change in the work environment so that staff members can rise to new levels of performance and self-esteem.


Asunto(s)
Administración de Personal , Recreación , Terapéutica , Humanos , Moral
20.
Am J Physiol ; 246(2 Pt 2): F133-9, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6696115

RESUMEN

Previous studies indicate that in hyperthyroid states the renal tubular reabsorption of phosphate is enhanced. To determine the cellular basis of this phenomenon, we investigated the effect of L-thyroxine (T4) administration on Pi transport across brush border membrane vesicles (BBMV) from rat renal cortex. Rats were thyroparathyroidectomized, fed a diet containing 1.2% phosphate, and treated intraperitoneally for 6 days with 200 micrograms T4 X 100 g body wt-1 X day-1. At the end of the treatment period, the rats had a significantly (+ delta 25%) elevated plasma Pi and a slightly decreased plasma Ca compared with controls. The renal clearance of Pi was not different between the two groups. Na+ gradient-dependent uptake of 32Pi by BBMV from renal cortex was significantly enhanced in T4-treated rats. BBMV uptake of 32Pi in the absence of Na+ -gradient as well as Na+ gradient-dependent uptake of D-[3H]glucose and L-[3H]proline did not differ between BBMV from T4-treated and control rats. Kinetic analysis showed that the Na+ gradient-dependent 32Pi transport system in BBMV from T4-treated rats had a significantly increased Vmax compared with controls (5.2 +/- 0.4 vs. 4.1 +/- 0.4 nmol Pi X 30 s-1 X mg protein-1) and also a slightly higher affinity for Pi (apparent Km in controls, 95 +/- 9; in T4-treated, 78 +/- 8 microM). Gluconeogenesis in cortical slices was not significantly different between T4-treated rats and controls. Specific activities of alkaline phosphatase and gamma-glutamyltransferase were significantly lower in BBMV from the T4-treated group compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Corteza Renal/metabolismo , Microvellosidades/metabolismo , Fosfatos/metabolismo , Tiroxina/farmacología , Animales , Transporte Biológico , Calcio/orina , Glucosa/metabolismo , Masculino , Microvellosidades/enzimología , Fosfatos/orina , Prolina/metabolismo , Ratas , Tiroxina/sangre , Factores de Tiempo
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