Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Zoolog Sci ; 37(2): 193-202, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32282150

RESUMEN

The Japanese wrinkled frog Glandirana rugosa is separated into five genetically different groups. One group in western Japan is further divided into three subgroups, found in Kyushu, Shikoku, and western Honshu. We collected G. rugosa frogs at 39 sites in Kyushu and determined nucleotide sequences of the mitochondrial 12S and 16S rRNA genes for phylogenetic analysis. Unexpectedly, we found a group of frogs in southeastern Kyushu that did not cluster with any of the pre-existing five groups of G. rugosa on the phylogenetic trees. The frogs in the new group and G. rugosa in Kyushu were externally similar, but there were a few significant differences in morphological features between the two populations. In addition, we observed significant differences in the frogs' calls . Thus, the group of the frogs in southeastern Kyushu may represent a new candidate species in the genus Glandirana. We discuss the possibility of a new species.


Asunto(s)
Ranidae/clasificación , Ranidae/genética , Animales , ADN Mitocondrial/genética , Femenino , Japón , Larva/anatomía & histología , Masculino , Filogenia , ARN Ribosómico 16S/genética , Ranidae/anatomía & histología , Ranidae/crecimiento & desarrollo , Análisis de Secuencia de ADN , Especificidad de la Especie , Vocalización Animal
2.
Zoolog Sci ; 35(4): 306-313, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30079832

RESUMEN

In the teleost fish medaka, an adult ovary simultaneously contains developing oocytes at all phases of oogenesis during the breeding season. However, it remains unclear where oocytes at each developmental stage are located in the ovary by the time of ovulation. To examine the relationship between the developmental stage of oocytes and their positions in the ovary of vertebrate medaka during oogenesis, the stage of oocyte development was determined from the diameter of the oocytes and the cellular morphological characteristics, such as the germinal vesicle and micropyle at the animal pole and attaching filaments at the vegetal pole, and the positions of developing oocytes in the ovary in all sections were observed. Furthermore, to investigate the characteristics of the dorsal ovarian epithelium to which the oocytes attach themselves, the dorsal and vegetal ovarian epithelia were observed. The dorsal ovarian epithelium invaginated in spots. When all serial sections of the oocytes were observed, all oocytes at stages I-VIII were attached to the dorsal ovarian epithelium, regardless of whether it invaginated or not.


Asunto(s)
Epitelio/fisiología , Oocitos/fisiología , Oryzias/fisiología , Ovario/fisiología , Animales , Femenino , Oogénesis , Ovulación
3.
N Engl J Med ; 369(18): 1715-25, 2013 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-24171517

RESUMEN

BACKGROUND: The cost-effectiveness of early antiretroviral therapy (ART) in persons infected with human immunodeficiency virus (HIV) in serodiscordant couples is not known. Using a computer simulation of the progression of HIV infection and data from the HIV Prevention Trials Network 052 study, we projected the cost-effectiveness of early ART for such persons. METHODS: For HIV-infected partners in serodiscordant couples in South Africa and India, we compared the early initiation of ART with delayed ART. Five-year and lifetime outcomes included cumulative HIV transmissions, life-years, costs, and cost-effectiveness. We classified early ART as very cost-effective if its incremental cost-effectiveness ratio was less than the annual per capita gross domestic product (GDP; $8,100 in South Africa and $1,500 in India), as cost-effective if the ratio was less than three times the GDP, and as cost-saving if it resulted in a decrease in total costs and an increase in life-years, as compared with delayed ART. RESULTS: In South Africa, early ART prevented opportunistic diseases and was cost-saving over a 5-year period; over a lifetime, it was very cost-effective ($590 per life-year saved). In India, early ART was cost-effective ($1,800 per life-year saved) over a 5-year period and very cost-effective ($530 per life-year saved) over a lifetime. In both countries, early ART prevented HIV transmission over short periods, but longer survival attenuated this effect; the main driver of life-years saved was a clinical benefit for treated patients. Early ART remained very cost-effective over a lifetime under most modeled assumptions in the two countries. CONCLUSIONS: In South Africa, early ART was cost-saving over a 5-year period. In both South Africa and India, early ART was projected to be very cost-effective over a lifetime. With individual, public health, and economic benefits, there is a compelling case for early ART for serodiscordant couples in resource-limited settings. (Funded by the National Institute of Allergy and Infectious Diseases and others.).


Asunto(s)
Antirretrovirales/economía , Transmisión de Enfermedad Infecciosa/prevención & control , Infecciones por VIH/tratamiento farmacológico , Adulto , Antirretrovirales/uso terapéutico , Análisis Costo-Beneficio , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Esquema de Medicación , Femenino , Producto Interno Bruto , Infecciones por VIH/economía , Infecciones por VIH/transmisión , Costos de la Atención en Salud , Humanos , India , Masculino , Sudáfrica
5.
Ann Intern Med ; 158(2): 84-92, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23318310

RESUMEN

BACKGROUND: U.S. HIV treatment guidelines recommend branded once-daily, 1-pill efavirenz-emtricitabine-tenofovir as first-line antiretroviral therapy (ART). With the anticipated approval of generic efavirenz in the United States, a once-daily, 3-pill alternative (generic efavirenz, generic lamivudine, and tenofovir) will decrease cost but may reduce adherence and virologic suppression. OBJECTIVE: To assess the clinical effect, costs, and cost-effectiveness of a 3-pill, generic-based regimen compared with a branded, coformulated regimen and to project the potential national savings in the first year of a switch to generic-based ART. DESIGN: Mathematical simulation of HIV disease. SETTING: United States. PATIENTS: HIV-infected persons. INTERVENTION: No ART (for comparison); 3-pill, generic-based ART; and branded ART. MEASUREMENTS: Quality-adjusted life expectancy, costs, and incremental cost-effectiveness ratios (ICERs) in dollars per quality-adjusted life-year (QALY). RESULTS: Compared with no ART, generic-based ART has an ICER of $21,100/QALY. Compared with generic-based ART, branded ART increases lifetime costs by $42,500 and per-person survival gains by 0.37 QALYs for an ICER of $114,800/QALY. Estimated first-year savings, if all eligible U.S. patients start or switch to generic-based ART, are $920 million. Most plausible assumptions about generic-based ART efficacy and costs lead to branded ART ICERs greater than $100,000/QALY. LIMITATION: The efficacy and price reduction associated with generic drugs are unknown, and estimates are intended to be conservative. CONCLUSION: Compared with a slightly less effective generic-based regimen, the cost-effectiveness of first-line branded ART exceeds $100,000/QALY. Generic-based ART in the United States could yield substantial budgetary savings to HIV programs. PRIMARY FUNDING SOURCE: National Institute of Allergy and Infectious Diseases.


Asunto(s)
Fármacos Anti-VIH/economía , Fármacos Anti-VIH/uso terapéutico , Medicamentos Genéricos/economía , Medicamentos Genéricos/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Adenina/análogos & derivados , Adenina/economía , Adenina/uso terapéutico , Alquinos , Benzoxazinas/economía , Benzoxazinas/uso terapéutico , Análisis Costo-Beneficio , Ciclopropanos , Desoxicitidina/análogos & derivados , Desoxicitidina/economía , Desoxicitidina/uso terapéutico , Combinación de Medicamentos , Emtricitabina , Femenino , Infecciones por VIH/complicaciones , Humanos , Masculino , Modelos Teóricos , Organofosfonatos/economía , Organofosfonatos/uso terapéutico , Años de Vida Ajustados por Calidad de Vida , Inhibidores de la Transcriptasa Inversa/economía , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Tenofovir , Estados Unidos
6.
Dev Biol ; 344(1): 272-83, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20471969

RESUMEN

The translational regulation of maternal mRNAs is one of the most important steps in the control of temporal-spatial gene expression during oocyte maturation and early embryogenesis in various species. Recently, it has become clear that protein components of mRNPs play essential roles in the translational regulation of maternal mRNAs. In the present study, we investigated the function of P100 in Xenopus oocytes. P100 exhibits sequence conservation with budding yeast Pat1 and is likely the orthologue of human Pat1a (also called PatL2). P100 is maternally expressed in immature oocytes, but disappears during oocyte maturation. In oocytes, P100 is an RNA binding component of ribosome-free mRNPs, associating with other mRNP components such as Xp54, xRAP55 and CPEB. Translational repression by overexpression of P100 occurred when reporter mRNAs were injected into oocytes. Intriguingly, we found that when P100 was overexpressed in the oocytes, the kinetics of oocyte maturation was considerably retarded. In addition, overexpression of P100 in oocytes significantly affected the accumulation of c-Mos and cyclin B1 during oocyte maturation. These results suggest that P100 plays a role in regulating the translation of specific maternal mRNAs required for the progression of Xenopus oocyte maturation.


Asunto(s)
Oocitos/metabolismo , Transcripción Genética , Proteínas de Xenopus/fisiología , Xenopus laevis/genética , Animales , Centrifugación por Gradiente de Densidad , Citoplasma/metabolismo , Femenino , Humanos , Cinética , Modelos Biológicos , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Ribosomas/metabolismo , Factores de Tiempo , Proteínas de Xenopus/genética
7.
Gen Comp Endocrinol ; 170(1): 207-12, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21036175

RESUMEN

In certain species of amphibians gonadal differentiation is influenced by steroid hormones. In the case of the frog Rana rugosa testosterone given to tadpoles reverses sex from female to male, while the opposite reversal - male to female - can be achieved using estradiol-17ß. In this study, we investigated whether CYP19 (P450 aromatase), the enzyme responsible for a production of estradiol-17ß, was present in the differentiating gonad of R. rugosa. Initially, we immunized rabbits against frog CYP19 peptides and performed immunostaining using specific antibodies purified from that serum. CYP19-reactive signals were observed in gonadal somatic cells of the female, but not male tadpoles at stage (St.) I (the stage prior to phenotypic sex determination in tadpoles of R. rugosa). Immunopositive signals were also produced in ovarian somatic cells froglets at St. XXV (just after the completion of metamorphosis). We also examined the enzymatic activity of CYP19 in the differentiating gonad of R. rugosa. Reverse-phase HPLC (high performance liquid chromatography) analysis revealed that [(3)H]testosterone was converted to [(3)H]estradiol-17ß in the gonad of tadpoles at St. I. Interestingly, the rate of conversion was much higher in females than in males. To the best of our knowledge, this is the first report on the biosynthesis of estradiol-17ß in the gonad of amphibians, and the co-incident identification of active CYP19 enzyme in the differentiating gonad of R. rugosa. Based on our results, we conclude that estradiol-17ß may be involved in ovarian differentiation in this species.


Asunto(s)
Estradiol/biosíntesis , Gónadas/metabolismo , Ranidae/metabolismo , Animales , Aromatasa/metabolismo , Western Blotting , Cromatografía Líquida de Alta Presión , Estradiol/metabolismo , Femenino , Inmunohistoquímica , Masculino
8.
Gen Comp Endocrinol ; 172(3): 475-86, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21521644

RESUMEN

In vertebrates, gonadal production of steroid hormones is regulated by follicle-stimulating hormone (FSH) and luteinizing hormone (LH) via their receptors designated FSHR and LHR, respectively. We have shown recently that steroid hormones are synthesized in the differentiating gonad of tadpoles during sex determination in the frog Rana rugosa. To elucidate the role of gonadotropins (GTHs) and their receptors in the production of gonadal steroid hormones during sex determination, we isolated the full-length FSHß, LHß, FSHR and LHR cDNAs from R. rugosa and determined gonadal expression of FSHR (FSH receptor) and LHR (LH receptor) as well as brain expression of FSHß and LHß during sex determination in this species. The molecular structures of these four glycoproteins are conserved among different classes of vertebrates. FSHß expression was observed at similar levels in the whole brain (including the pituitary) of tadpoles, but it showed no sexual dimorphism during gonadal sex determination. By contrast, LHß mRNA was undetectable in the whole brain of tadpoles. FSHß-immunopositive cells were observed in the pituitary of female tadpoles with a differentiating gonad. Furthermore, FSHR expression was significantly higher in the gonad of female tadpoles during sex determination than in that of males, whereas LHR was expressed at similar levels in males and females. The results collectively suggest that FSHR, probably in conjunction with FSH, is involved in the steroid-hormone production during female-sex determination in R. rugosa.


Asunto(s)
Ranidae/fisiología , Receptores de HFE/genética , Procesos de Determinación del Sexo/genética , Regulación hacia Arriba , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Encéfalo/metabolismo , Clonación Molecular , ADN Complementario/metabolismo , Hormona Folículo Estimulante de Subunidad beta/química , Hormona Folículo Estimulante de Subunidad beta/genética , Hormona Folículo Estimulante de Subunidad beta/metabolismo , Hormona Luteinizante de Subunidad beta/química , Hormona Luteinizante de Subunidad beta/genética , Hormona Luteinizante de Subunidad beta/metabolismo , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Ranidae/genética , Ranidae/metabolismo , Receptores de HFE/química , Receptores de HFE/metabolismo , Receptores de HL/química , Receptores de HL/genética , Receptores de HL/metabolismo , Alineación de Secuencia , Caracteres Sexuales , Factores Sexuales
9.
Mitochondrial DNA B Resour ; 5(3): 3721-3722, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33367075

RESUMEN

The Japanese Glandirana rugosa phylogenetically consists of four groups. However, the taxonomic identity of these groups still remains unclear. We determined the complete mitogenome sequences of the four groups of G. rugosa. The mitogenomes were 17,394-17,781 bp in length. The phylogenetic analysis clearly showed that the genus Glandirana is monophyletic and that the four groups of G. rugosa are separated into two clusters: one cluster represents G. rugosa, the other cluster may represent a different species.

10.
J Exp Zool A Ecol Integr Physiol ; 333(9): 652-659, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32851801

RESUMEN

Steroid hormones play very important roles in gonadal differentiation in many vertebrate species. Previously, we have determined a threshold dosage of testosterone (T) to induce female-to-male sex reversal in Glandirana rugosa frogs. Genetic females formed a mixture of testis and ovary, the so-called ovotestis, when tadpoles of G. rugosa were reared in water containing the dosage of T, which enabled us to detect primary changes in the histology of the masculinizing gonads. In this study, we determined a threshold dosage of estradiol-17ß (E2) to cause male-to-female sex reversal in this frog. We observed first signs of histological changes in the ovotestes, when tadpoles were reared in water containing the dosage of E2. Ovotestes were significantly larger than wild-type testes in size. By E2 treatment, male germ cells degenerated in the feminizing testis leading to their final disappearance. In parallel, oocytes appeared in the medulla of the ovotestis and later in the cortex as well. Quantitative polymerase chain reaction analysis revealed that the expression of sex-related genes involved in testis formation was significantly decreased in the ovotestis. In addition, immuno-positive signals of CYP17 that is involved in testis differentiation in this frog disappeared in the medulla first and then in the cortex. These results suggested that oocytes expanded in the feminizing gonad (ovary) contemporaneously with male germ cell disappearance. Primary changes in the histology of the gonads during male-to-female sex reversal occurred in the medulla and later in the cortex. This direction was opposite to that observed during female-to-male sex reversal in the G. rugosa frog.


Asunto(s)
Estradiol/farmacología , Ranidae/crecimiento & desarrollo , Animales , Estradiol/administración & dosificación , Femenino , Regulación del Desarrollo de la Expresión Génica , Gónadas/efectos de los fármacos , Gónadas/crecimiento & desarrollo , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Ranidae/genética , Ranidae/metabolismo , Procesos de Determinación del Sexo/efectos de los fármacos
11.
BMJ Glob Health ; 4(5): e001822, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31565420

RESUMEN

High-performing primary health care (PHC) is essential for achieving universal health coverage. However, in many countries, PHC is weak and unable to deliver on its potential. Improvement is often limited by a lack of actionable data to inform policies and set priorities. To address this gap, the Primary Health Care Performance Initiative (PHCPI) was formed to strengthen measurement of PHC in low-income and middle-income countries in order to accelerate improvement. PHCPI's Vital Signs Profile was designed to provide a comprehensive snapshot of the performance of a country's PHC system, yet quantitative information about PHC systems' capacity to deliver high-quality, effective care was limited by the scarcity of existing data sources and metrics. To systematically measure the capacity of PHC systems, PHCPI developed the PHC Progression Model, a rubric-based mixed-methods assessment tool. The PHC Progression Model is completed through a participatory process by in-country teams and subsequently reviewed by PHCPI to validate results and ensure consistency across countries. In 2018, PHCPI partnered with five countries to pilot the tool and found that it was feasible to implement with fidelity, produced valid results, and was highly acceptable and useful to stakeholders. Pilot results showed that both the participatory assessment process and resulting findings yielded novel and actionable insights into PHC strengths and weaknesses. Based on these positive early results, PHCPI will support expansion of the PHC Progression Model to additional countries to systematically and comprehensively measure PHC system capacity in order to identify and prioritise targeted improvement efforts.

12.
PLoS One ; 12(6): e0178067, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28582396

RESUMEN

INTRODUCTION: In the Japanese frog Rana (R.) rugosa the androgen receptor (AR) gene on the W chromosome (W-AR) is barely expressed. Previously we showed that incomplete female-to-male sex-reversal occurred in Z-AR transgenic female frogs. To date, however, there is no report showing that AR with androgens can determine genetically programed male sex fate in any vertebrate species. Here, we examined whether AR together with androgens functions as a sex determinant in an amphibian species. METHODS: To examine whether complete female-to-male sex-reversal occurs in R. rugosa frogs, we produced AR-transgenic (Tg) and -knockdown (KD) female R. rugosa frogs by the I-SceI meganuclease-mediated gene trap and CRISPR/Cas9 system, respectively. AR-Tg and -KD tadpoles were reared in water containing testosterone (T) at 0 to 7.1 ng/ml. Frozen sections were prepared from the gonads of metamorphosed frogs and immunostained for laminin, Vasa, Pat1a, CYP17 and AR. We also employed PCR analysis to examine Dmrt1, Pat1a and CYP17 expression in the gonads of KD and placebo-KD female frogs. RESULTS: Complete female-to-male sex-reversal occurred in the AR-Tg ZW female frogs when a low dosage of T was supplied in the rearing water of tadpoles. However, no sex-reversal was observed in AR-KD ZW female frogs when the gonads were treated with dosages of T high enough to induce complete female-to-male sex-reversal even in wild type frogs. DISCUSSION: These results suggest that AR with its androgen ligand functions as a male sex-determinant in the ZW type R. rugosa frogs.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Ranidae/genética , Receptores Androgénicos/genética , Cromosomas Sexuales/efectos de los fármacos , Procesos de Determinación del Sexo , Testosterona/farmacología , Proteínas Anfibias/genética , Proteínas Anfibias/metabolismo , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Sistemas CRISPR-Cas , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II/genética , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Femenino , Edición Génica , Técnicas de Silenciamiento del Gen , Laminina/genética , Laminina/metabolismo , Larva/efectos de los fármacos , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Masculino , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Ranidae/crecimiento & desarrollo , Ranidae/metabolismo , Receptores Androgénicos/deficiencia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Cromosomas Sexuales/química , Cromosomas Sexuales/metabolismo , Análisis para Determinación del Sexo , Esteroide 17-alfa-Hidroxilasa/genética , Esteroide 17-alfa-Hidroxilasa/metabolismo , Testosterona/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
13.
J Exp Zool A Ecol Integr Physiol ; 327(7): 444-452, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-29356406

RESUMEN

Each vertebrate species, as a general rule, has either the XX/XY or ZZ/ZW chromosomes by which sex is determined. However, the Japanese Rana (R.) rugosa frog is an exception, possessing both sex-determining combinations within one species, varying with region of origin. We collected R. rugosa frogs from 104 sites around Japan and South Korea and determined the nucleotide sequences of the mitochondrial 12S ribosomal RNA gene. Based on the sequences, R. rugosa frogs were divided into four groups from Japan and one from South Korea. The ZZ/ZW type is reportedly derived from the XX/XY type, although recently a new ZZ/ZW type of R. rugosa was reported. However, it still remains unclear from where the sex chromosomes in the five groups of this species were derived. In this study, we successfully isolated a sex-linked DNA maker and used it to classify R. rugosa frogs into several groupings. From the DNA marker as well as from nucleotide analysis of the promoter region of the androgen receptor (AR) gene, we identified another female heterogametic group, designated, West-Central. The sex chromosomes in the West-Central originated from the West and Central groups. The results indicate that a sex-linked DNA marker is a verifiable tool to determine the origin of the sex chromosomes in R. rugosa frogs in which the sex-determining system has changed, during two independent events, from the male to female heterogamety.


Asunto(s)
ADN/genética , Marcadores Genéticos , Ranidae/genética , Cromosomas Sexuales/genética , Distribución Animal , Animales , Femenino , Japón , Masculino , Filogenia , Procesos de Determinación del Sexo , Especificidad de la Especie
14.
J Exp Zool A Ecol Genet Physiol ; 325(8): 532-538, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27677985

RESUMEN

Androgens play a critical role in testicular differentiation in many species of vertebrates. While female-to-male sex reversal can be induced by testosterone (T) in some species of amphibians, the mechanism still remains largely unknown even at the histological level. In this study, we determined a threshold dosage of T to induce female-to-male sex reversal in the Japanese frog Rana (R.) rugosa. Tadpoles were allowed to metamorphose into frogs with T present in the rearing water. At 0.2 ng/mL T, female frogs formed tissue comprising a mixture of ovary and testis, the so-called ovotestis, the size of which was significantly smaller than the wild-type ovary. Histological changes occurring in the oocytes of T-treated ovaries induced oocyte degeneration in the masculinizing ovaries leading to their final disappearance. In parallel, many germ cells emerged in the cortex of the ovotestis and, later, in the medulla as well. RT-PCR analysis revealed upregulated expression of CYP17 and Dmrt1 but not 17ßHSD in the ovotestis, and downregulation of Pat1a expression. Furthermore, immunohistology revealed CYP17-positive signals in the cortex of the masculinizing ovary, spreading throughout the whole area as the testis developed. These results indicate that oocytes are sensitive to T in the ovary of R. rugosa and that male-type germ cells expand in the masculinizing gonad (testis) contemporaneous with oocyte disappearance.


Asunto(s)
Gónadas/crecimiento & desarrollo , Metamorfosis Biológica , Ranidae/crecimiento & desarrollo , Desarrollo Sexual , Testosterona/sangre , Proteínas Anfibias/genética , Animales , Femenino , Regulación del Desarrollo de la Expresión Génica , Células Germinativas , Gónadas/metabolismo , Masculino , Ranidae/sangre
15.
J Exp Zool A Ecol Genet Physiol ; 325(3): 209-18, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27076437

RESUMEN

The phenotypic sex of many species of amphibians is subject to reversal by steroid hormones. The mechanism of this process, however, still remains largely unknown. As a step toward understanding the histological changes during sex reversal in amphibians, we analyzed two- and three-dimensional (2D and 3D) structures of sex-reversing gonads in Rana rugosa frogs. 2D views revealed that many oocytes in the wild-type ovary disappeared during female-to-male sex-reversal concomitant with the emergence of Vasa-positive small germ cells. Some of the germ cells were labeled with BrdU. BrdU-positive germ cells were few in the testosterone (T) treated ovaries at days 8 and 16, which resembled wild-type ovaries. Basement membranes became disrupted by day 24 in T-treated ovaries. However, the membranes were later reconfigured into testis-like gonadal structures 40 days after T treatment. 3D imaging of the sex-reversing gonad using serial immunostained sections showed that germ cells were organized in linear fashion extending out from where the sex-reversing gonad attached to the mesorchium 24 days after T treatment. Germ cells were increased in number by 40 days and were localized to the cortex of the gonads. In a T-untreated testis at day 24, many germ cells were distributed throughout the cortex except in the central space, while the efferent duct ran between two sheets of the mesorchium. These results, taken together, suggest that the mesorchium plays an important role in the organization of testicular structure. This is the first report showing germ cell ontogeny and organization in the female-to-male sex-reversing gonad in a vertebrate species.


Asunto(s)
Gónadas/anatomía & histología , Ranidae/anatomía & histología , Diferenciación Sexual , Animales , Femenino , Células Germinativas/citología , Células Germinativas/efectos de los fármacos , Gónadas/citología , Gónadas/efectos de los fármacos , Larva/anatomía & histología , Larva/efectos de los fármacos , Masculino , Ranidae/crecimiento & desarrollo , Testosterona/farmacología
16.
Health Aff (Millwood) ; 35(5): 847-55, 2016 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-27140991

RESUMEN

Launched in 2003, the US President's Emergency Plan for AIDS Relief (PEPFAR) is the largest disease-focused assistance program in the world. We analyzed PEPFAR budgets for governance and systems for the period 2004-14 to ascertain whether PEPFAR's stated emphasis on strengthening health systems has been manifested financially. The main outcome variable in our analysis, the first of its kind using these data, was the share of PEPFAR's total annual budget for a country that was designated for governance and systems. The share of planned PEPFAR funding for governance and systems increased from 14.9 percent, on average, in 2004 to 27.5 percent in 2013, but it declined in 2014 to 20.8 percent. This study shows that the size of a country's PEPFAR budget was negatively associated with the share allocated for governance and systems (compared with other budget program areas); it also shows that there was no significant relationship between budgets for governance and systems and HIV prevalence. It is crucial for the global health policy community to better understand how such investments are allocated and used for health systems strengthening.


Asunto(s)
Atención a la Salud/economía , Programas de Gobierno/economía , Infecciones por VIH/epidemiología , Política de Salud/economía , Inversiones en Salud/economía , Presupuestos/organización & administración , Países en Desarrollo , Salud Global/economía , Humanos , Cooperación Internacional , Asistencia Médica/economía , Estados Unidos
17.
Biochem J ; 379(Pt 1): 65-70, 2004 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-14690456

RESUMEN

To identify the genes involved in pyridoxine synthesis in yeast, auxotrophic mutants were prepared. After transformation with a yeast genomic library, a transformant (A22t1) was obtained from one of the auxotrophs, A22, which lost the pyridoxine auxotrophy. From an analysis of the plasmid harboured in A22t1, the RKI1 gene coding for ribose 5-phosphate ketol-isomerase and residing on chromosome no. 15 was identified as the responsible gene. This notion was confirmed by gene disruption and tetrad analysis on a diploid prepared from the wild-type and the auxotroph. The site of mutation on the RKI1 gene was identified as position 566 with a transition from guanine to adenine, resulting in amino acid substitution of Arg-189 with lysine. The enzymic activity of the Arg189-->Lys (R189K) mutant of ribose 5-phosphate ketolisomerase was 0.6% when compared with the wild-type enzyme. Loss of the structural integrity of the protein seems to be responsible for the greatly diminished activity, which eventually leads to a shortage of either ribose 5-phosphate or ribulose 5-phosphate as the starting or intermediary material for pyridoxine synthesis.


Asunto(s)
Isomerasas Aldosa-Cetosa/metabolismo , Piridoxina/biosíntesis , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Proteínas de Transporte Vesicular , Isomerasas Aldosa-Cetosa/química , Isomerasas Aldosa-Cetosa/genética , Sustitución de Aminoácidos , Proteínas Portadoras , Mapeo Cromosómico , Genes Fúngicos , Mutación Missense , Mutación Puntual , Proteínas Recombinantes de Fusión/metabolismo , Ribosamonofosfatos/metabolismo , Ribulosafosfatos/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Transformación Genética
18.
Endocrinology ; 156(5): 1914-23, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25714810

RESUMEN

The role of anti-Müllerian hormone (AMH) during gonad development has been studied extensively in many species of mammal, bird, reptile, and fish but remains unresolved in amphibians. In male mammalian embryos, Sox9 activates AMH expression, which initiates regression of the Müllerian ducts. However, Sox9 (Sry-related HMG box 9) is unlikely to initiate AMH in chicken, because AMH precedes Sox9 expression in this species. To clarify whether AMH is involved in testicular differentiation in amphibians, we cloned the full-length AMH cDNA from the Japanese wrinkled frog, Rana rugosa. The AMH gene, which appears to be autosomal, is exclusively expressed in the testis of adult frog among 8 different tissues examined; Sertoli cells are probably responsible for its expression. AMH expression was found in the undifferentiated gonad of both male and female tadpoles, increasing in the differentiating testis. Moreover, we observed consensus binding sites for Sox9 in the 5'-flanking region of the AMH gene. Sox9 stimulated statistically significant AMH expression in luciferase reporter assays when coexpressed in Xenopus kidney-derived A6 cells. However, Sox9 expression showed no sexual dimorphism when AMH expression was up-regulated in the developing testis. These results, taken together, suggest that AMH is probably involved in testicular differentiation in R. rugosa, although an additional, perhaps tissue-specific, transcription factor may be required for the regulation of AMH transcription.


Asunto(s)
Hormona Antimülleriana/genética , Regulación del Desarrollo de la Expresión Génica , ARN Mensajero/metabolismo , Factor de Transcripción SOX9/genética , Testículo/metabolismo , Animales , Hormona Antimülleriana/metabolismo , Clonación Molecular , ADN Complementario , Larva , Masculino , Ranidae , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción SOX9/metabolismo
19.
J Exp Zool A Ecol Genet Physiol ; 323(8): 516-26, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26136381

RESUMEN

The Pat1 gene is expressed in the immature oocytes of Xenopus, and is reportedly involved in regulating the translation of maternal mRNAs required for oocyte-maturation. However, it is still unknown when Pat1a first appears in the differentiating ovary of amphibians. To address this issue, we isolated the full-length Pat1a cDNA from the frog Rana rugosa and examined its expression in the differentiating ovary of this frog. Among eight different tissues examined, the Pat1a mRNA was detectable in only the ovary. When frozen sections from the ovaries of tadpoles at various stages of development were immunostained for Vasa-a germ cell-specific protein-and Pat1a, Vasa-immunopositive signals were observed in all of the germ cells, whereas Pat1a signals were confined to the growing oocytes (50-200 µm in diameter), and absent from small germ cells (<50 µm in diameter). Forty days after testosterone injection into tadpoles to induce female-to-male sex-reversal, Pat1a-immunoreactive oocytes had disappeared completely from the sex-reversed gonad, but Vasa-positive small germ cells persisted. Thus, Pat1a would be a good marker for identifying the sexual status of the sex-reversing gonad in amphibians. In addition, fluorescence in situ hybridization analysis showed Pat1a to have an autosomal locus, suggesting that Pat1a transcription is probably regulated by a tissue-specific transcription factor in R. rugosa.


Asunto(s)
Oocitos/metabolismo , Ranidae/genética , Animales , Clonación Molecular , ADN Complementario/genética , Femenino , Expresión Génica , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Masculino , Ovario/crecimiento & desarrollo , Ovario/ultraestructura , Ranidae/crecimiento & desarrollo , Ranidae/metabolismo , Procesos de Determinación del Sexo , Testosterona/farmacología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
20.
J Acquir Immune Defic Syndr ; 68(2): 152-61, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25415289

RESUMEN

OBJECTIVE: HIV genotype-resistance testing can help identify more effective antiretroviral treatment (ART) regimens for patients, substantially increasing the likelihood of viral suppression and immune recovery. We sought to evaluate the cost-effectiveness of genotype-resistance testing before first-line ART initiation in Brazil. DESIGN: We used a previously published microsimulation model of HIV disease (CEPAC-International) and data from Brazil to compare the clinical impact, costs, and cost-effectiveness of initial genotype testing (Genotype) with no initial genotype testing (No genotype). METHODS: Model parameters were derived from the HIV Clinical Cohort at the Evandro Chagas Clinical Research Institute and from published data, using Brazilian sources whenever possible. Baseline patient characteristics included 69% male, mean age of 36 years (SD, 10 years), mean CD4 count of 347 per microliter (SD, 300/µL) at ART initiation, annual ART costs from 2012 US $1400 to US $13,400, genotype test cost of US $230, and primary resistance prevalence of 4.4%. Life expectancy and costs were discounted 3% per year. Genotype was defined as "cost-effective" compared with No Genotype if its incremental cost-effectiveness ratio was less than 3 times the 2012 Brazilian per capita GDP of US $12,300. RESULTS: Compared with No genotype, Genotype increased life expectancy from 18.45 to 18.47 years and reduced lifetime cost from US $45,000 to $44,770; thus, in the base case, Genotype was cost saving. Genotype was cost-effective at primary resistance prevalence as low as 1.4% and remained cost-effective when subsequent-line ART costs decreased to 30% of baseline value. Cost-inefficient results were observed only when simultaneously holding multiple parameters to extremes of their plausible ranges. CONCLUSIONS: Genotype-resistance testing in ART-naive individuals in Brazil will improve survival and decrease costs and should be incorporated into HIV treatment guidelines in Brazil.


Asunto(s)
Antirretrovirales/uso terapéutico , Farmacorresistencia Viral , Técnicas de Genotipaje/economía , Técnicas de Genotipaje/métodos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH/efectos de los fármacos , Adulto , Brasil , Simulación por Computador , Análisis Costo-Beneficio , Femenino , VIH/genética , VIH/aislamiento & purificación , Costos de la Atención en Salud , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Análisis de Supervivencia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA