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1.
Cell Death Dis ; 2: e195, 2011 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-21866174

RESUMO

Hearing loss is often caused by death of the mechanosensory hair cells of the inner ear. Hair cells are susceptible to death caused by aging, noise trauma, and ototoxic drugs, including the aminoglycoside antibiotics and the antineoplastic agent cisplatin. Ototoxic drugs result in permanent hearing loss for over 500,000 Americans annually. We showed previously that induction of heat shock proteins (HSPs) inhibits both aminoglycoside- and cisplatin-induced hair cell death in whole-organ cultures of utricles from adult mice. In order to begin to translate these findings into a clinical therapy aimed at inhibiting ototoxic drug-induced hearing loss, we have now examined a pharmacological HSP inducer, celastrol. Celastrol induced upregulation of HSPs in utricles, and it provided significant protection against aminoglycoside-induced hair cell death in vitro and in vivo. Moreover, celastrol inhibited hearing loss in mice receiving systemic aminoglycoside treatment. Our data indicate that the major heat shock transcription factor HSF-1 is not required for celastrol-mediated protection. HSP32 (also called heme oxygenase-1, HO-1) is the primary mediator of the protective effect of celastrol. HSP32/HO-1 inhibits pro-apoptotic c-Jun N-terminal kinase (JNK) activation and hair cell death. Taken together, our data indicate that celastrol inhibits aminoglycoside ototoxicity via HSP32/HO-1 induction.


Assuntos
Aminoglicosídeos/toxicidade , Antibacterianos/toxicidade , Heme Oxigenase-1/metabolismo , Triterpenos/farmacologia , Animais , Antineoplásicos/toxicidade , Apoptose , Cisplatino/toxicidade , Células Ciliadas Auditivas/citologia , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/metabolismo , Perda Auditiva/induzido quimicamente , Heme Oxigenase-1/genética , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Endogâmicos CBA , Modelos Animais , Triterpenos Pentacíclicos , Sáculo e Utrículo/efeitos dos fármacos , Sáculo e Utrículo/metabolismo
2.
Public Health Rep ; 116(1): 22-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11571405

RESUMO

OBJECTIVES: The onset and severity of the clinical expression of most diseases that are of public health importance are influenced by genetic predisposition. The ability to assess human genetic predisposition for many diseases is increasing rapidly. Therefore, state public health agencies should be incorporating new developments in genetics and disease prevention into their core functions of assessment, policy development, and assurance. The authors assessed the status of this process. METHODS: The Council of State and Territorial Epidemiologists (CSTE) surveyed states about projects and concerns related to genetics and public health activities. Respondents were the Health Officer, the Maternal and Child Health/Genetics Program Director, the Chronic Disease Program Director, and the Laboratory Director. Where applicable, responses were categorized into assessment, policy development, and assurance functions. RESULTS: Thirty-eight (76%) state health departments responded. Ongoing genetics activities were assurance (82%), assessment (17%), and policy development (2%). In contrast, Health Officers responded that future genetics activities would be distributed differently: assurance, 41%; assessment, 36%; and policy development, 23%. Future assurance activities would be largely educational. Topics of interest and recently initiated activities in genetics were primarily assessment functions. Funding was the greatest concern, followed by lack of proven disease prevention measures and outcomes data. CONCLUSIONS: State health departments recognize a need to realign their activities to meet future developments in genetics. Lack of adequate resources, proven disease prevention measures, and outcomes data are potential barriers. Public health agencies need to develop a strategic plan to meet the opportunities associated with the development and implementation of genetic tests and procedures.


Assuntos
Doenças Genéticas Inatas/prevenção & controle , Genética Médica/organização & administração , Serviços Preventivos de Saúde/organização & administração , Administração em Saúde Pública , Governo Estadual , Planos Governamentais de Saúde/organização & administração , United States Public Health Service/organização & administração , Coleta de Dados , Previsões , Testes Genéticos , Política de Saúde , Pesquisa sobre Serviços de Saúde , Humanos , Avaliação das Necessidades , Objetivos Organizacionais , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Estados Unidos
3.
Community Genet ; 4(1): 2-11, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11493747

RESUMO

Objectives: To examine the opportunities for and responsibilities of the public health community in bridging the gap between gene discovery and the application of genetic information to improve health and prevent disease. Methods: We developed genetics-related definitions for the core functions and essential services of public health. We combined these definitions with a visual model to create one possible 'blueprint' for integrating genomics into public health activities. Results: The proposed blueprint and accompanying examples illustrate the important role for genomics throughout public health research, policy and practice. Further refinement and implementation of this blueprint represents an ambitious public health leadership agenda. Conclusions: Opportunities for immediate action include strategic planning for the integration of genomics across programs, developing genomics competencies among health professionals, enhancing surveillance and epidemiologic capacity to aid evidence-based policy making, building partnerships and seeking input from stakeholders and incorporating information about genomics into health communications. Copyright 2001 S. Karger AG, Basel

4.
J Reprod Fertil ; 119(2): 339-46, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10864847

RESUMO

The O(6)-alkylguanine-DNA alkyltransferase inactivator O(6)-benzylguanine was administered to BALB/c mice either alone or before exposure to 1,3-bis(2-chloroethyl)-1-nitrosourea to study the role of the DNA repair protein O(6)-alkylguanine-DNA alkyltransferase in the protection of the testis against anti-cancer O(6)-alkylating agents. Exposure of the mice to 1, 3-bis(2-chloroethyl)-1-nitrosourea or O(6)-benzylguanine alone did not produce any marked testicular toxicity at the times studied. Testicular O(6)-alkylguanine-DNA alkyltransferase concentrations were assayed between 0 and 240 min after O(6)-benzylguanine treatment and were shown to be > 95% depleted 15 min after treatment with O(6)-benzylguanine and remained at > 95% at all the times assayed. Histological examination, the reduction in testicular mass and the induction of spermatogenic cell apoptosis showed that this depletion significantly potentiated 1, 3-bis(2-chloroethyl)-1-nitrosourea-induced testicular damage after treatment. Major histological damage was apparent 42 days after treatment, demonstrating that the stem spermatogonia were significantly affected by the combination. These results demonstrate that O(6)-alkylguanine-DNA alkyltransferase plays a significant role in protecting the spermatogenic cells from damage caused by DNA alkylation and indicate that the observed toxicity may result from damage to stem spermatogonia.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Carmustina/toxicidade , Guanina/análogos & derivados , O(6)-Metilguanina-DNA Metiltransferase/antagonistas & inibidores , O(6)-Metilguanina-DNA Metiltransferase/fisiologia , Epitélio Seminífero/enzimologia , Espermatogônias/efeitos dos fármacos , Análise de Variância , Animais , Antineoplásicos Alquilantes/farmacocinética , Apoptose/efeitos dos fármacos , Carmustina/farmacocinética , Reparo do DNA/efeitos dos fármacos , Resistência a Medicamentos , Inibidores Enzimáticos/farmacologia , Guanina/farmacologia , Meia-Vida , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Epitélio Seminífero/efeitos dos fármacos , Epitélio Seminífero/patologia , Espermatogônias/patologia , Testículo/efeitos dos fármacos , Testículo/enzimologia , Testículo/patologia , Fatores de Tempo
5.
Eur J Haematol ; 64(4): 231-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10776694

RESUMO

A high prevalence of iron-deficiency anaemia has been reported in Jordanian infants. A prospective study of infants in downtown Amman examined the relationship between anaemia in pregnancy and iron deficiency in infancy. The iron status of infants born to 107 anaemic (Hb < 11 g/dl) and 125 non-anaemic mothers was reviewed at 3, 6, 9 and 12 months. Indicators to define iron-deficiency anaemia were Hb < 11 g/dl and either plasma ferritin < 12 microg/l or zinc protoporphyrin (ZPP) > 35 microg/dl whole blood. Haemoglobin electrophoresis excluded haemoglobinopathy. There was 72% iron-deficiency anaemia throughout the year, significantly higher in infants born to anaemic mothers (81%; n = 91) compared with controls (65%; n = 112). At 12 months, 72% of the infants tested (n = 195) were anaemic. While 57% were identified as iron-deficient by research criteria of either ferritin or ZPP, only 37% were identified by ferritin alone, 40% by ZPP alone and 29% if both ferritin and ZPP were required to meet criteria. Most infant anaemia was identified as due to iron deficiency, supporting contextual setting as assisting diagnosis: infants in developing countries are recognised as vulnerable to iron deficiency. Using multiple criteria, more cases were identified when either ferritin or ZPP were abnormal than when one alone, or both parameters were required to meet research criteria.


Assuntos
Anemia Ferropriva/epidemiologia , Anemia Ferropriva/genética , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Jordânia/epidemiologia , Gravidez , Estudos Prospectivos
6.
Ann Saudi Med ; 20(5-6): 371-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-17264625

RESUMO

BACKGROUND: A high prevalence of anemia has been reported in Jordan affecting women of childbearing age and infants/preschool children. This paper considers maternal iron, folate and B(12) status, with possible implications for both maternal and infant health. PATIENTS AND METHODS: A case-control study of infants born to anemic (Hb <11 g/dL) (n=107) and non-anemic mothers (n=125) from birth to one year, was conducted in a lower middle-class urban setting in Amman, Jordan. Maternal hematology included full blood count (FBC), plasma ferritin, transferrin saturation, serum folate and B(12) at term, and FBC and ferritin at 6 months postpartum. Serum B(12) was reassessed at 6 and 12 months postpartum if antenatal values were low. Infant FBC and ferritin were assessed in cord blood and at 3, 6, 9 and 12 months, and zinc protoporphyrin (ZPP) from 6 months. RESULTS: Anemic mothers (mean [SD] Hb 9.9 [0.7] g/dL) had significantly lower antenatal values for Hb, MCV, MCH, transferrin saturation, plasma ferritin and serum folate than non-anemic mothers (mean Hb 12.2 [0.9] g/dL), which persisted at 6 months postpartum. Antenatal B(12) values were low (<200 pg/mL) in 67% of samples (26% <100 pg/mL), evenly distributed between the groups, and, therefore, not related to maternal anemia. Low values persisted in 27% (n=127) and in 61% (n=31), respectively, at 6 and 12 months postpartum. Iron deficiency anemia (Hb <11 g/dL and either ferritin <12 mcg/L or ZPP >35 mcg/dL) affected 72% of infants, with significantly higher incidence in those born to anemic mothers. Ambiguous hematology in 11% of infants may have reflected other nutritional deficiencies, including vitamin B(12), where mothers had depleted values. CONCLUSION: Iron, folate and B(12) status should be monitored during pregnancy/lactation in developing countries, where nutritional deprivation is more prevalent and women of childbearing age often have a high fertility rate and inadequate inter-pregnancy interval to replenish body stores. Infant health may also be at risk through a compromised endowment of these micronutrients at birth.

7.
Int J Epidemiol ; 28(3): 461-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10405849

RESUMO

BACKGROUND: A high prevalence of 50-65% iron-deficiency anaemia in mothers and infants in Jordan was reported by the United Nations Relief and Works Agency (UNRWA) in 1990. Iron-deficiency in infancy has been shown to delay cognitive and psychomotor development with long-term consequences. While socioeconomic deprivation and inadequate nutrition are known underlying factors, it is unclear whether iron endowment at birth is compromised when mothers are anaemic, further jeopardizing iron status during infancy. A prospective case-control study of infants from birth to one year was conducted in a lower middle-class urban setting in Amman, Jordan. The study objective was to examine the relationship between maternal anaemia and iron-deficiency anaemia during infancy. METHOD: A sample of 107 anaemic (Hb < 11 g/dl) and 125 non-anaemic mothers was selected at 37 weeks' gestation and matched for age and parity, and infant data at birth obtained. The infants were reviewed at 3, 6, 9 and 12 months, to assess growth, current nutrition, infection rates and iron status. The main outcome measure was the incidence of iron-deficiency anaemia in the two groups of infants, defined in the study as Hb < 11 g/dl and either plasma ferritin < 12 mcg/l or zinc protoporphyrin > 35 mcg/dl. RESULTS: Iron endowment in cord blood samples appeared similar between the two groups. The incidence of iron-deficiency anaemia was very high in these infants, at 72% by research criteria, (51% if Hb < 10.5 g/dl), but significantly higher in the infants born to anaemic mothers at all stages of the year, with overall incidence of 81% (n = 91), compared to 65% in controls (n = 112). This was not explained by differences in environmental risk factors. Anaemic mothers had not recovered adequate iron status at 6 months' postpartum, with implications for future pregnancy iron demands. CONCLUSIONS: Anaemia during pregnancy compromises the health of mothers in traditional cultures, where women tend to have several children close together after marriage, with an inadequate interval to replenish nutritional stores. Their infants also appear to be at increased risk of developing iron-deficiency anaemia, undetected at birth.


Assuntos
Anemia Ferropriva/epidemiologia , Complicações Hematológicas na Gravidez/epidemiologia , Estudos de Casos e Controles , Feminino , Ferritinas/sangue , Sangue Fetal/química , Humanos , Lactente , Jordânia/epidemiologia , Masculino , Gravidez , Estudos Prospectivos , Protoporfirinas/sangue , Fatores de Risco
8.
Br J Dermatol ; 135(2): 204-10, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8881661

RESUMO

Alopecia areata is a form of balding whose aetiology is uncertain. Although the dermal papilla in the hair bulb regulates the follicle and may play a part in the pathogenesis of alopecia areata, its ultrastructure has not been well described. As clinically normal, i.e. non-balding, follicles from alopecia areata scalps show abnormalities at the light microscope level, it would be expected that they should exhibit the earliest pathological changes involved in the dysfunction of the follicle. This study was designed to investigate the ultrastructure of normal human scalp follicular dermal papillae and to see if changes occurred in the ultrastructure of dermal papillae from either lesional or non-balding regions of alopecia areata. Normal dermal papillae contained well formed fibroblast-like cells with large, oval nuclei and well-developed endoplasmic reticulum; the cells were separated from each other by extracellular matrix containing small pieces of collagen and basal lamina-like material. Dermal papillae from both clinically normal and lesional alopecia areata follicles were less well organized and the dermal papilla cells exhibited signs of cell injury and contained abnormal amounts of pigment; an increased concentration of fibrous material in the extracellular matrix and thickening of the dermal papilla-epithelial junction were also seen. Follicles from lesional areas showed more pronounced changes than clinically normal ones. Ultrastructural abnormalities in the dermal papillae of clinically normal scalp follicles support the study of these follicles as a prime research target. The changes detected suggest that dermal papilla cells in alopecia areata would be less able to synthesize regulatory factors and that these may have more difficulty crossing into the epithelial compartment. They are consistent with an early pathological role for the dermal papilla in alopecia areata, but do not distinguish whether this is a primary aetiological role or a secondary response to an insult elsewhere in the follicle.


Assuntos
Alopecia em Áreas/patologia , Folículo Piloso/ultraestrutura , Couro Cabeludo/ultraestrutura , Adolescente , Adulto , Biópsia , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade
9.
Reprod Toxicol ; 10(1): 71-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8998388

RESUMO

Alkylating agents are a group of compounds that have a cytotoxic effect due to their ability to form adducts with DNA. Cells possess the ability to repair this damage via an enzyme, O6-alkylguanine-DNA alkyltransferase (AGT). To study the effect of inhibiting this repair mechanism upon testicular cytotoxicity in BALB/c mice, the AGT inhibitor O6 benzylguanine (O6BG) was used in conjunction with the potential anticancer drug B.4152. Paraffin sections were stained and examined using Chalkley scoring to identify the cells affected by the treatment. Using B.4152 alone the maximal effect upon the spermatogenic tissue was found to be after 32 days. The damage found was minor, with the spermatocytes and spermatids most affected. Using this time point it was found that the combined treatment produced widespread damage, with significant depletion of the majority of spermatogenic cell types. These results therefore, indicate that differentiating spermatogenic cells are normally protected from B.4152 induced damage by AGT, depletion of which significantly potentiates B.4152 toxicity.


Assuntos
Antimetabólitos Antineoplásicos/toxicidade , Inibidores Enzimáticos/toxicidade , Etilnitrosoureia/análogos & derivados , Fluoruracila/toxicidade , Guanina/análogos & derivados , Metiltransferases/antagonistas & inibidores , Testículo/efeitos dos fármacos , Análise de Variância , Animais , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Sinergismo Farmacológico , Etilnitrosoureia/toxicidade , Guanina/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , O(6)-Metilguanina-DNA Metiltransferase , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/patologia , Espermatogênese/efeitos dos fármacos , Testículo/patologia
10.
Public Health Rep ; 106(6): 634-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1659709

RESUMO

The National AIDS Clearinghouse is an information service provided by the Centers for Disease Control. The Clearinghouse was established in 1987 to respond to increasing numbers of public and professional inquiries, to disseminate accurate information, and to make referrals to local sources of information and assistance. Four data bases--Resources and Services Database containing information about more than 16,000 organizations that provide counseling and testing for human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) and other education and prevention services; Educational Materials Database containing more than 8,000 individual, hard-to-find educational materials; Funding Database; and the AIDS Clinical Trial Information Service (ACTIS) Database--are searched by information specialists to respond to more than 45,000 requests annually for information from a variety of health professionals, organizations, and the general public. Between 1987 and 1991, the Clearinghouse disseminated more than 60 million copies of publications related to HIV and AIDS. Information and education remain the most critical tools for the prevention of HIV infection, and the National AIDS Clearinghouse provides an essential element for the dissemination of education and prevention information.


Assuntos
Síndrome da Imunodeficiência Adquirida/prevenção & controle , Serviços de Informação , Centers for Disease Control and Prevention, U.S. , Bases de Dados Bibliográficas , Educação em Saúde , Ocupações em Saúde , Serviços de Saúde , Linhas Diretas , Humanos , Serviços de Informação/organização & administração , Controle de Qualidade , Encaminhamento e Consulta , Materiais de Ensino , Estados Unidos
11.
Br J Cancer ; 58(2): 139-43, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3166903

RESUMO

Anti-tumour responses with CCRG81010, M & B 39565, NSC 353451, 8-carbamoyl-3-(2-chloroethyl)imidazo [5,1-d]-1,2,3,5-tetrazin-4(3H)-one (Mitozolomide) in a panel of 4 murine colon tumours of varying growth characteristics and chemosensitivity and a spontaneous murine lymphoma are similar to those seen with standard nitrosoureas. The moderately well differentiated colon adenocarcinoma MAC 16 is nonresponsive to mitozolomide and methylCCNU. Responses in the other 4 lines studied are only achieved near to maximum tolerated dose and at this level there is severe host toxicity. Haemopoietic toxicity is clearly demonstrated by analysis of peripheral blood counts and by CFU-S assays and severe testicular and ovarian toxicity was also seen at dose levels necessary to achieve anti-tumour effects. Using mitozolomide as an example, the study has demonstrated the feasibility of conducting simple but thorough toxicity evaluation for the determination of the therapeutic index. This approach would provide invaluable guidelines for the selection for clinical trial of the most appropriate members of a series of new cytotoxic compounds.


Assuntos
Antineoplásicos/uso terapêutico , Compostos de Mostarda Nitrogenada/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Animais , Contagem de Células Sanguíneas , Neoplasias do Colo/tratamento farmacológico , Ensaio de Unidades Formadoras de Colônias , Avaliação Pré-Clínica de Medicamentos , Feminino , Linfoma/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos , Compostos de Mostarda Nitrogenada/toxicidade , Oócitos/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Contagem de Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos
12.
J Anat ; 158: 65-75, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3225226

RESUMO

A proportion of mice with the genotype T16H/XSxr develop as hermaphrodites (Ward et al. 1987). In this study, histological sections were prepared of the gonads and reproductive tract from a number of such animals. Examination of the sections showed a wide range of development. The most common types of gonad found were sterile testes resembling those found in XXSxr males and apparently normal ovaries. However, between these two extremes were some gonads which were classified as ovotestes. These ovotestes covered such a range of sexual development that they were for convenience divided into two groups. Type I ovotestes were similar in appearance to the Sxr-type testes with the exception that oocytes surrounded by granulosa-like cells were present in some seminiferous tubules. Also, many tubules had shed their Sertoli cell lining. The structure of Type II ovotestes was even more bizarre; regions of both testicular and ovarian somatic tissue and widespread areas of haemorrhage were seen. In general, the histological structure of the reproductive ducts approached the normal pattern. The epididymal ducts were small and haemorrhage was present in some epididymides associated with the Type II ovotestes.


Assuntos
Transtornos do Desenvolvimento Sexual/patologia , Ovário/patologia , Testículo/patologia , Animais , Feminino , Masculino , Camundongos , Camundongos Mutantes
13.
J Reprod Fertil ; 81(2): 295-300, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3430453

RESUMO

Sexual development was studied in 25 hermaphrodite mice with the genotype T16H/XSxr. The majority of the animals had a male phenotype similar to that seen in XXSxr males. A few, however, had feminized external genitalia and were classified as females. Examination of the gonads and reproductive tracts of the male hermaphrodites revealed a strong tendency for the left gonad to be more masculine than the right. Most of the gonads in male and female hermaphrodites appeared to be ovaries or testes rather than ovotestes.


Assuntos
Transtornos do Desenvolvimento Sexual/patologia , Ovário/patologia , Testículo/patologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Fenótipo
14.
Clin Sci (Lond) ; 73(1): 53-9, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3608377

RESUMO

The structural integrities of various preparations of rat small intestine for the study of absorption in vitro have been compared after incubation or perfusion. Perfused intestines removed from anaesthetized rats, and thus never deprived of a supply of oxygen, maintain their structural integrity even after perfusion for 1 h provided that a Krebs-Henseleit bicarbonate perfusate is used. However, intestines removed from freshly killed rats show severe villus disruption and oedema after perfusion for only 20 min. Extensive damage to both crypts and villi is observed in everted sacs of small intestine incubated for 20 min, regardless of the buffer system used. Intestinal rings show damage at the tips of the villi after incubation for 2 min, but otherwise remain morphologically intact; this damage is progressive with time. It is concluded that the exact mode of preparation of intestinal tissue is critical for preservation of structural and functional integrity and that this is especially important in quantitative studies on transport processes. Further, it is recommended that routine monitoring of the integrity of intestinal preparations in vitro is desirable and that histological assessment is an appropriate technique.


Assuntos
Intestino Delgado/citologia , Manejo de Espécimes/métodos , Animais , Técnicas In Vitro , Absorção Intestinal , Mucosa Intestinal/citologia , Intestino Delgado/metabolismo , Jejuno/citologia , Jejuno/metabolismo , Masculino , Microvilosidades/ultraestrutura , Perfusão , Ratos , Ratos Endogâmicos , Sobrevivência de Tecidos
19.
J Reprod Fertil ; 75(2): 633-45, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3906118

RESUMO

Postnatally, XO mice have approximately half as many oocytes as their XX sisters. A quantitative histological analysis of XO and XX ovaries throughout oogenesis (14 1/2-24 1/2 days post coitum) revealed that this oocyte deficiency in XO mice is due to excess atresia of oocytes at the late pachytene stage (19 1/2 days post coitum). Female mice heterozygous for a large X inversion (In(X)/X mice) were also found to have excess atresia at late pachytene. It was suggested that in XO mice it is the presence of an unpaired X chromosome, and in In(X)/X mice, the incompleteness of X chromosome pairing, which leads to this excess oocyte atresia. A new quantitative histological procedure which was developed for the analysis of perinatal mouse ovaries is also described.


Assuntos
Oócitos/fisiologia , Ovário/embriologia , Síndrome de Turner/embriologia , Animais , Contagem de Células , Técnicas Citológicas , Feminino , Humanos , Meiose , Camundongos , Ovário/citologia , Síndrome de Turner/etiologia
20.
J Endocrinol ; 106(2): 233-42, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4040549

RESUMO

Reproductive tissues, steroid hormone secretion, and sexual behaviour have been examined in five gilts, in each of which the right gonad was an ovotestis. Although from different females, these animals were sired by the same boar and each possessed an XX sex chromosome constitution as determined by karyotype analysis of blood cells. Despite variable amounts of testicular tissue in the ovotestis and unilateral development of a prominent epididymis, four of the animals had oestrous cycles of normal duration (20-22 days) and extended periods of standing oestrus (3-6 days). The fifth animal did not have detectable oestrous cycles but was extremely aggressive in the presence of a mature boar. Two of the gilts were mated, and there were small numbers of embryos in each uterine horn 23 and 26 days later. Removal of the ovary did not prompt compensatory hypertrophy in the ovarian portion of the ovotestis, nor did injection of pregnant mare serum gonadotrophin stimulate detectable follicular growth in ovarian tissue adjoining testicular tissue. Concerning the aetiology of this intersex condition, the unilateral appearance of an ovotestis precludes any simple involvement of a translocated portion of the Y chromosome or systemic effects of unusual titres of the putative H-Y antigen. However, bearing in mind a predisposition to gonadal asymmetry in eutherian mammals, a case is advanced for apposition or incorporation of adrenocortical tissue in the right embryonic ovary. The resultant virilization of neighbouring reproductive tissues would stem from adrenocortical androgen synthesis.


Assuntos
Transtornos do Desenvolvimento Sexual/fisiopatologia , Estro , Fertilidade , Hormônios Esteroides Gonadais/sangue , Ovário/fisiopatologia , Testículo/fisiopatologia , Animais , Transtornos do Desenvolvimento Sexual/sangue , Transtornos do Desenvolvimento Sexual/patologia , Feminino , Genótipo , Masculino , Ovário/patologia , Gravidez , Comportamento Sexual Animal , Suínos , Testículo/patologia
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