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1.
Reprod Fertil Dev ; 32(8): 748-762, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32362313

RESUMO

Cattle undergo numerous environmental and management stressors that reduce fertility and affect ovulation. The extracellular matrix of the follicle wall can be altered by matrix metalloproteinases (MMPs), the activities of which are regulated by interleukins and tissue-specific inhibitors of metalloproteinases (TIMPs), especially during ovulation. The aims of the present study were to: (1) evaluate changes in the hormone milieu, the localisation and activity of MMP2 and MMP9 and the localisation of MMP14, TIMP1 and TIMP2 in response to adrenocorticotrophic hormone (ACTH) during the preovulatory period in cows; and (2) determine the direct effects of ACTH on the mRNA expression of MMP2 and MMP9 in the cultured follicle wall of bovine ovaries obtained from an abattoir. 100IU ACTH was administered during pro-oestrus every 12h until ovariectomy, which was performed before ovulation. Cortisol concentrations in the plasma and follicular fluid (FF) of preovulatory follicles were higher in ACTH-treated than control cows. Progesterone presented subluteal concentrations in plasma of ACTH-treated cows (P<0.05). MMP2 immunostaining and activity in ovaries were higher in ACTH-treated than control cows (P<0.05), whereas MMP9 immunostaining was similar between the two groups. However, unlike in control cows, MMP9 activity was absent in the FF of ACTH-treated cows. These results suggest that the administration of ACTH during the preovulatory period in cows could cause changes that culminate in modifications in the content and activation of MMPs and TIMPs in the ovary, which could interfere with the ovulation process.


Assuntos
Hormônio Adrenocorticotrópico/administração & dosagem , Bovinos/fisiologia , Expressão Gênica/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz/metabolismo , Metaloproteinases da Matriz/genética , Ovário/enzimologia , Animais , Feminino , Líquido Folicular/enzimologia , Metaloproteinase 14 da Matriz/análise , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/genética , Inibidores de Metaloproteinases de Matriz/análise , Metaloproteinases da Matriz/análise , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/enzimologia , Ovariectomia , Ovulação/fisiologia , RNA Mensageiro/análise , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-2/análise
2.
Rev. argent. endocrinol. metab ; 56(2): 1-20, jun. 2019. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1125825

RESUMO

RESUMEN La vitamina D (VD), un esteroide pleiotrópico, ha sido relacionada con la función reproductiva masculina, pero aún no se ha estudiado la expresión de su receptor (RVD) en el desarrollo testicular. RVD regula la expresión de componentes del sistema histaminérgico, y la histamina (HA) modula la esteroidogénesis en células de Leydig (CL). Se ha relacionado a la deficiencia de VD con múltiples patologías, entre ellas cáncer. Los tumores de células de Leydig (TCL) son los más frecuentes del intersticio testicular, y al malignizar no responden a radio/quimioterapia. VD fue descripta como tratamiento para varios tumores, pero se desconoce su aplicación en TCL. Por lo expuesto, hemos estudiado la expresión de RVD en la ontogenia de testículo de rata, evaluando su correlación con los niveles de testosterona séricos (T) y el contenido de HA; y además evaluamos la expresión de RVD en testículo humano fetal, neonatal, prepuberal, TCL e hiperplasia de CL. En testículo de rata, se observó un aumento en la expresión de RVD en CL con la edad, en línea con el incremento de T, y en contraposición con la disminución del contenido de HA, lo cual fue consistente con la reducción en los niveles de la enzima que cataliza su síntesis, HDC. Esto sugiere que la VD podría ejercer una función en el desarrollo testicular normal, ya sea en forma directa sobre las CL o mediante la regulación de la expresión de componentes del sistema histaminérgico (HDC y/o receptores de HA). Por su parte, el TCL humano presentó sobreexpresión de RVD y HDC. Considerando que las hormonas esteroideas se encuentran aumentadas en esta patología y funcionan como factores de crecimiento, si el calcitriol pudiera modular la esteroidogénesis podría tener una aplicación terapéutica.


ABSTRACT Vitamin D (VD) is a steroid hormone traditionally related to bone health. However, several authors have associated VD with reproduction and steroidogenesis in males. The presence ofVD receptor (VDR) and the enzymes involved in its activation had been reported in several cell types of the testes. Until now, nobody has studied RVD expression during testicular development. In addition, VDR in association with its co-activators or co-repressors, regulates the expression of several genes, including those related to the histaminergic system. Previously, we demonstrated that histamine (HA) can modulate steroidogenesis in Leydig cells (LC) in a concentration-dependent manner. Also, we observed a decrease in the endogenous HA content, consistent with the previously described decrease of HDC (histidine decarboxylase, the enzyme responsible of HA synthesis) levels, during LC ontogeny. Epidemiologic studies strongly suggest that a relationship exists between VD deficiency and multiple pathologies, particularly cancer. Leydig cell tumors (LCT) are rare endocrine tumors ofunknown etiology, which originate in the testicular interstitium. The incidence worldwide is 1-3% in adults and 4% in prepubertal boys, but recent publications indicate that these figures have been increasing. While usually benign, approximately 10% of LCT in adults become malignant and do not respond to chemo or radiotherapy. It is imperative to deeply investigate the biology of LCT, to identify new therapeutic targets. The potential role of calcitriol (1a,25(OH)2-vitamin-D3) in cancer treatment has been described for several types of tumors, but it remains unexplored in LCT. Thus, as a first step, it is worth evaluating VDR expression in LCT.In view of the aforecited evidence, herein we studied VDR expression during the rat testicular ontogeny, evaluating a possible correlation withserum testosterone (T) levels in blood, endogenous levels of HA and the previously described HDC expression levels. We also analized VDR expression in human testes corresponding to three different stages of development (fetal, neonatal andjuvenile), in LCT and in LC hyperplasia. Methods: Rat testes of different ages (7, 21, 35, 90 y 240 days), human fetal, neonatal and pre pubertal testes, a human LCT and a human LC hyperplasia; were used for detection of VDR by immunohistochemistry. Results: In the rat testes, VDR expression increased with age in LC, in line with the increase in serum testosterone; and in contrast with the decrease in the endogenous content of HA and HDC levels. Likewise, we detected an increase in VDR expression with age in the human testes samples. LCT presentedVDR and HDC overexpression. We also detected VDR in LC hyperplasia. Conclusions: Given that VDR testicular expression increases with age in LC, as well as testosterone serum levels, it is reasonable to speculate thatVD may play a role in normal testicular development, either acting directly on LC or by regulating one of more components of the histaminergic system (HDC or HA receptors). Considering that VDR is overexpressed in LCT, and that steroids are increased in this pathology (and act like growth factors); if calcitriol could modulate steroidogenesis, it could have a therapeutic role.

3.
Clin Exp Immunol ; 196(1): 86-96, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30580455

RESUMO

Merozoite surface proteins (MSPs) are critical for parasite invasion; they represent attractive targets for antibody-based protection against clinical malaria. To identify protection-associated target MSPs, the present study analysed antibody responses to whole merozoite extract (ME) and to defined MSP recombinant antigens in hospitalized patients from a low endemic urban area as a function of disease severity (mild versus cerebral malaria). Sera from 110 patients with confirmed severe cerebral malaria (CM) and 91 patients with mild malaria (MM) were analysed (mean age = 29 years) for total and subclass immunoglobulin (Ig)G to ME and total IgG to MSP1p19, MSP2, MSP3, MSP4 and MSP5 by enzyme-linked immunosorbent assay (ELISA). Functional antibody responses were evaluated using the antibody-dependent respiratory burst (ADRB) assay in a subset of sera. There was a trend towards higher IgG1 and IgG4 levels to ME in CM compared to MM; only ME IgM responses differed significantly between fatal and surviving CM patients. Increased prevalence of IgG to individual MSPs was found in the CM compared to the MM group, including significantly higher levels of IgG to MSP4 and MSP5 in the former. Sera from fatal (24·5%) versus surviving cases showed significantly lower IgG to MSP1p19 and MSP3 (P < 0·05). ADRB assay readouts correlated with high levels of anti-MSP IgG, and trended higher in sera from patients with surviving compared to fatal CM outcome (P = 0·07). These results document strong differential antibody responses to MSP antigens as targets of protective immunity against CM and in particular MSP1p19 and MSP3 as prognostic indicators.


Assuntos
Antígenos de Protozoários/imunologia , Extratos Celulares/imunologia , Malária Cerebral/imunologia , Malária Falciparum/imunologia , Merozoítos/imunologia , Plasmodium falciparum/imunologia , População Urbana , Adolescente , Adulto , Idoso , Anticorpos Antiprotozoários/sangue , Criança , Pré-Escolar , Progressão da Doença , Feminino , Hospitalização , Humanos , Imunoglobulina M/sangue , Lactente , Malária Cerebral/mortalidade , Malária Falciparum/mortalidade , Masculino , Proteína 1 de Superfície de Merozoito/imunologia , Pessoa de Meia-Idade , Proteínas Recombinantes/imunologia , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
4.
Rev. argent. endocrinol. metab ; 55(4): 1-10, dic. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-1041748

RESUMO

Resumen Los tumores de células de Leydig (TCL) son tumores endócrinos del intersticio testicular, cuya incidencia se encuentra en aumento. Los síntomas incluyen feminización o virilización en pacientes prepuberales, y pérdida de libido, disfunción eréctil, infertilidad y/o ginecomastia en adultos. Si bien son usualmente benignos, cuando malignizan en adultos no responden a radio y quimioterapia. Múltiples trabajos han reportado que la histidina decarboxilasa (HDC), enzima que cataliza la conversión de L-histidina en histamina (HA), tiene un rol importante en el desarrollo de tumores. A su vez, en nuestro laboratorio demostramos que la HA induce la proliferación de células de Leydig tumorales (CLT) murinas, mientras que la inhibición de HDC disminuye su proliferación y capacidad esteroidogénica. Además, observamos elevada expresión de HDC en TCL pediátricos vs. controles de distintos estadios de madurez sexual; y se ha descrito que ratones knock out para HDC poseen una angiogénesis incompleta. Para evaluar el rol de HDC en la modulación de la angiogénesis se empleó la línea de CLT de rata R2C, principal modelo utilizado en estudios de Leydigioma. También se realizaron estudios en TCL pediátricos. Los medios condicionados por las CLT R2C estimularon la angiogénesis tanto in vitro como in vivo (empleando HUVEC y analizando el grado de vascularización de membranas corioalantoideas de codorniz, respectivamente). El efecto in vitro se revirtió al tratar previamente las CLT R2C con α-metil-DL-histidinadihidrocloruro, inhibidor específico de HDC. A su vez, tanto la HA como los medios condicionados provenientes de TCL pediátricos, produjeron un aumento en la proliferación de las HUVEC. Nuestros resultados sugieren que las CLT producen HA y otros factores proangiogénicos, y que la inhibición selectiva de HDC atenúa la capacidad proangiogénica de las CLT. En base a estos resultados y evidencias previas del laboratorio, inhibidores específicos de HDC podrían ser utilizados como potencial terapia neoadyuvante en TCL.


ABSTRACT Leydig Cell tumors (LCT) are a rare group of endocrine tumors in the testicular interstitium. Between 1 and 3% of testicular malignances in adults and 4% in prepubertal children belong to LCT. An increasing incidence of this type of neoplasia has been reported recently all around the world. Particularly, a strong relationship between LCT and the use of anabolic steroids (which are commonly used nowadays) has been reported recently. In prepubertal boys, symptoms include feminization or virilization, depending on the major circulating steroid (estradiol or testosterone respectively). Adult patients show loss of libido, penile dysfunction, infertility and/or gynecomastia. Although the etiology still is unknown, several studies indicate that tumoral Leydig cells have an excessive production of insulin-like growth factor (IGF-1), as well as aromatase (CYP19) overexpression, which causes an enormous amount of estrogens (particularly estradiol, E2), and both factors play an important role in tumorigenesis. While usually benign, when LCT became malignant in adults they respond poorly to radio and chemotherapy. Likewise, it has been reported that both therapies increase the incidence of several tumors. All these data imply the need of new therapeutic targets to avoid the chirurgical dissection of the testes and the consequences of the hormonal therapies associated, which implicate not only the loss in reproductive function, but also psychological disorders. Several publications have reported that histidine decarboxylase (HDC), the only enzyme capable of catalyzing the conversion from L-histidine to histamine (HA) in mammals, has an important role in the development of several types of tumors, such as colorectal, breast and melanoma. At the same time, in our laboratory we have reported that HA induces cell proliferation of murine Leydig cells, and complementary, this cell proliferation decreases when inhibiting selectively HDC, as well as steroid synthesis (progesterone and E2). Also, we observed a higher expression of HDC in pediatric LCT (n = 3) than normal controls corresponding to different stages of sexual maturation (n = 9). It has been described that HDC knock out mice have an incomplete angiogenesis, and also that MA-10 Leydig cells HDC expression correlates with vascular endothelial growth factor (VEGF). The aim of this study is to improve our knowledge about the role of HDC in LCT biology, particularly, the angiogenesis modulation. We used the R2C Leydig cell line, the most used model for in vitro studies of Leydigioma, because it overexpresses CYP19 and constitutively produces high levels of IGF-1 and E2, as well as human LCT. R2C and pediatric LCT angiogenic capability was evaluated in vitro by measuring proliferation of human umbilical vein endothelial cells (HUVEC). In addition, we verified R2C cells angiogenic capability in vivo, using quail embryo vasculature (chorioallantoic membrane assay). Both models have been validated for the study of angiogenesis. Conditioned medium obtained from R2C cell culture stimulated angiogenesis in vitro (p <0.001) as well as in vivo (p <0.001). The in vitro effect was reverted with a previous treatment on the R2C cell culture using α-methyl-DL-histidine hydrochloride (α-MHD, 10 µM), a specific HDC activity inhibitor (p <0.001). Finally, human conditioned medium from pediatric LCT increased HUVEC proliferation (p <0.01). In the same way, the analyzed patients showed higher testosterone and estradiol levels than normal serum concentrations, which was in concordance to phenotypical features observed in presence of LCT. Our results indicate that tumoral Leydig cells (TLC) produce HA, as well as other angiogenic factors, and it could be stimulating the vascular endothelium. The selective inhibition of HDC attenuates the pro-angiogenic capability in TLC. Considering all these results and previous observations of our laboratory, specific inhibitors of HDC could be used, in the future, as a potential therapeutic target for the treatment of LCT.

5.
Bull Soc Pathol Exot ; 109(2): 91-8, 2016 May.
Artigo em Francês | MEDLINE | ID: mdl-27100862

RESUMO

Malaria remains a major health problem in sub- Saharan African countries despite substantial decreases in morbidity and mortality due to sustained control programs. Vaccines candidates were mainly tested in rural endemic setting; however increasing proportion of the population is living in urban area. Evaluation of the qualitative or quantitative immune responses to key targets of anti-Plasmodium immunity requires further investigation in urban area. In a cohort of 144 patients with mild malaria living in Dakar, we analyzed IgG responses against target antigens of P. falciparum: CSP, LSA-3NR2 and GLURP by ELISA. A mean age of 15 yrs (4-65 yrs) was found and patients were separated in 59 adults (<15yrs) and 85 children (≤15 yrs). Parasites densities (0,01-15%) did not differ between the two age groups. In contrast, haemoglobin levels appeared lower in children (4.5-16.6 g/dl) (p<0.01). For the immune results, the most recognized antigens were GLURP and CSP compared to LSA-3NR2. Levels of IgG against these antigens were significantly different between the two age groups and they were positively correlated (rho = 0.32; p<0.001). In addition, levels of IgG anti-GLURP were associated with low parasitemia (≤1%) and absence of anemia (≥11g/dl), particularly in adults (p<0.001). In a multiple regression analysis, no significant relationship was found between parasite densities and IgG responses against all the tested antigens. Our study shows the implication of IgG anti-GLURP in humoral immune response against the parasite. The present work contributes to determine IgG levels that can be used as relevant immunologic biomarkers in urban clinical malaria.


Assuntos
Hemoglobinas/análise , Imunoglobulina G/análise , Vacinas Antimaláricas/imunologia , Malária Falciparum/sangue , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Carga Parasitária , Adolescente , Adulto , Idoso , Anticorpos Antiprotozoários/análise , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Parasitemia/sangue , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , População Urbana , Adulto Jovem
6.
Aquat Toxicol ; 156: 30-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25146234

RESUMO

In oviparous vertebrates, vitellogenin (VTG) is mainly produced by the liver in response to estrogen (E2) and its synthesis is traditionally coupled to estrogen receptor alpha induction. Even though VTG is a female-specific protein, chemicals that mimic natural estrogens, known as xenoestrogens, can activate its expression in males causing endocrine disruption to wildlife and humans. Alkylphenols such as nonylphenol (NP) and octylphenol (OP) are industrial additives used in the manufacture of a wide variety of plastics and detergents, and can disrupt endocrine functions in exposed animals. For more than a decade, the freshwater cichlid fish Cichlasoma dimerus has been used for ecotoxicological studies in our laboratory. We recently found an up-regulation of VTG gene expression in livers of male fish exposed to OP, from a silent state to values similar to those of E2-induced fish. To better understand the underlying mechanisms behind the action of xenoestrogens, the aim of this study was to analyze the dose-response relationship of C. dimerus VTG and estrogen receptors (ERs) gene expression after waterborne exposure to 0.15, 1.5, 15, and 150µg/L OP for up to 1 month (0, 1, 3, 7, 14, 21, and 28 days). At the end of the experiment, histological features of exposed fish included active hepatocytes with basophilic cytoplasm and high eosinophilic content in their vascular system due to augmented expression of VTG. In testis, high preponderance of sperm was found in fish exposed to 150µg/L OP. A classic dose-response down-regulation of the expression of Na(+)/K(+)-ATPase, a "non-gender specific gene" used for comparison, was found with increasing OP concentrations. No VTG and very low levels of ERα were detected in control male livers, but an up-regulation of both genes was found in males exposed to 0.15 or 150µg/L OP. Moreover, VTG transcripts were significant as early as day 3 or day 1 of exposure to these OP concentrations, respectively. Nearly no response was detected in 1.5 and 15µg/L OP exposed-fish. Data was curve-fitted evidencing a nonmonotonic dose-response curve. Interestingly, ERß2 mRNA expression was augmented above baseline levels only when males were exposed to the lowest OP concentration. We speculate that genomic control of vitellogenesis is under control of multiple steroid receptors with different affinities for ligands. ERß isoform, only up-regulated with very low concentrations of ligand, would act as a sensors of OP (or E2) to induce ERα and VTG. With high OP concentrations, the expression of ERα isoform is promptly augmented, with the concomitant VTG transactivation.


Assuntos
Ciclídeos/genética , Receptor alfa de Estrogênio/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Fenóis/toxicidade , Vitelogeninas/genética , Poluentes Químicos da Água/toxicidade , Animais , Ciclídeos/metabolismo , Disruptores Endócrinos/toxicidade , Receptor alfa de Estrogênio/metabolismo , Feminino , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Testículo/efeitos dos fármacos , Vitelogeninas/metabolismo
7.
Int J Lab Hematol ; 34(2): 208-13, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22032515

RESUMO

INTRODUCTION: The updated guidelines for lupus anticoagulant (LA) diagnosis indicate locally calculate the cut-off values of the index of circulating anticoagulant (ICA) and the clotting time in seconds (s) for mixing studies and % of correction (%C) for confirmatory tests. We assess sensitivity (SEN) and specificity (SPC) of the cut-off values obtained as the 99th percentile from 60 plasmas of healthy individuals. METHODS: We analysed 647 plasmas from patients studied in the last 3 years, and results were revaluated according to the new criteria and cut-off values. Four hundred and three had LA, and 75 of them were under oral anticoagulants (OA). We performed three screening tests: activated partial thromboplastin time (APTT), diluted Russell viper venom time (dRVVT) and dilute prothrombin time (dPT), and previous diagnosis was carried out using our home-made cut-off calculated by receiver operating characteristics curves. We reanalysed the mixing and confirmatory data of APTT/dRVVT, the tests selected in the new guidelines. To evaluate SPC, 244 plasmas (160 OA and 84 congenital deficient patients) were studied. RESULTS: Considering mixing studies, the cut-off values demonstrate that SEN of ICA-APTT was 94% and of clotting time in second (s) 83%, with an SPC of 77% and 84%, respectively. For ICA-dRVVT, SEN was 72% and for clotting time in second (s) 77%, with SPC of 98% and 84%, respectively. The cut-off values for %C for confirmatory APTT show good SEN 82% and high SPC 96%; for confirmatory dRVVT lower SEN 77%, but a SPC of 100%. CONCLUSION: The combination of mixing and confirmatory tests interpreted according to the new guidelines can clearly differentiate LA from other coagulopathies.


Assuntos
Síndrome Antifosfolipídica/diagnóstico , Inibidor de Coagulação do Lúpus , Guias de Prática Clínica como Assunto/normas , Testes de Coagulação Sanguínea , Humanos , Sensibilidade e Especificidade
8.
Clin Biochem ; 43(3): 234-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19804771

RESUMO

OBJECTIVES: HIF-1 alpha (hypoxia-inducible factor-1 alpha) mediates the responses of mammalian cells to hypoxia/ischemia by inducing the expression of adaptive gene products (e.g., vascular endothelial growth factor (VEGF) and erythropoietin (EPO)). Persistent pulmonary hypertension of the newborn (PPHN) and cyanotic congenital heart disease (CCHD) are common neonatal diseases considered as paradigms of hypoxemia. Since the expression HIF-1 alpha, VEGF and EPO in newborns diagnosed with these diseases has yet to be studied, we set out to define the expression of these genes in peripheral blood from newborn infants diagnosed with PPHN and CCHD. DESIGN AND METHODS: The mRNA transcripts encoding HIF-1 alpha, VEGF and EPO were measured by RT-PCR in healthy newborn infants and infants diagnosed with PPHN and CCHD. RESULTS: An important increase in HIF-1 alpha expression was observed in both pathological conditions, accompanied by significant increases in VEGF and EPO expression when compared to healthy infants. CONCLUSIONS: HIF-1 alpha mRNA expression increases in newborn infants with PPHN or CCHD, as does the expression of its target genes VEGF and EPO.


Assuntos
Eritropoetina , Cardiopatias , Subunidade alfa do Fator 1 Induzível por Hipóxia , Hipóxia , Síndrome da Persistência do Padrão de Circulação Fetal , Fator A de Crescimento do Endotélio Vascular , Eritropoetina/sangue , Eritropoetina/genética , Cardiopatias/sangue , Cardiopatias/congênito , Cardiopatias/fisiopatologia , Humanos , Hipóxia/sangue , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/sangue , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Lactente , Recém-Nascido , Síndrome da Persistência do Padrão de Circulação Fetal/sangue , Síndrome da Persistência do Padrão de Circulação Fetal/genética , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/genética
9.
J Perinatol ; 26(7): 423-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16688205

RESUMO

OBJECTIVE: To determine sildenafil citrate (SC) genotoxicity and cytotoxicity in the Callithrix jacchus. STUDY DESIGN: Fifteen organisms were assigned to one of three groups as follows: experimental (25 mg/kg of SC); negative control (glucose solution 5%); and positive control (3 mg/kg of cytocine arabinoside). Systemic hemodynamic changes were monitored in each animal before and after each treatment. A drop of blood was obtained before and after the treatment at 24-120 h. Smears were made and the frequency of micronucleated erythrocytes (MNE), micronucleated polychromatic erythrocytes (MNPCE) and polychromatic erythrocytes (PCE) was counted. RESULTS: No significant differences in MNE, MNPCE and PCE were found in the group that received sildenafil and negative control. A significant increase in genotoxicity and cytotoxicity was observed in the positive control group. No changes were observed in systemic hemodynamic changes. CONCLUSION: The macro-dose of SC lacks genotoxic, cytotoxic or systemic hemodynamic changes effects in this species.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , Aberrações Cromossômicas/induzido quimicamente , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Piperazinas/toxicidade , Vasodilatadores/toxicidade , Administração Oral , Animais , Pressão Sanguínea/efeitos dos fármacos , Callithrix , Modelos Animais de Doenças , Eritrócitos/patologia , Frequência Cardíaca/efeitos dos fármacos , Testes de Mutagenicidade , Piperazinas/administração & dosagem , Purinas , Distribuição Aleatória , Citrato de Sildenafila , Sulfonas , Vasodilatadores/administração & dosagem
11.
Blood Coagul Fibrinolysis ; 13(7): 623-6, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12439148

RESUMO

The purpose of the present study was to investigate the role of risk factors predisposing to thrombosis in patients with central retinal vein occlusion (CRVO). We prospectively examined 37 consecutive patients with CRVO, and 144 healthy controls, for major and potential inherited and acquired thrombophilic risk factors. Among them, only the prevalence of hyperhomocysteinaemia (10/37, 27.0%) and antiphospholipid antibodies positivity (5/37, 13.5%) were significantly higher in patients with respect to controls (5.5%, P < 0.001 and 2.1%, P < 0.01, respectively). Both hyperhomocysteinaemia and antiphospholipid antibodies seem to be associated with CRVO. A search for acquired thrombophilia is advisable in patients with CRVO.


Assuntos
Oclusão da Veia Retiniana/sangue , Trombofilia/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antifosfolipídeos/sangue , Biomarcadores/sangue , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/genética , Estudos de Casos e Controles , Feminino , Humanos , Hiper-Homocisteinemia/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/genética , Fatores de Risco , Trombofilia/genética , Trombose/etiologia , Trombose/genética
12.
Thromb Res ; 104(5): 317-24, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11738073

RESUMO

Factor V Leiden (FVL) and the prothrombin 20210A (PT-20210A) variant are well-known risk factors for venous thromboembolism (VT). The thermolabile variant (TT) of the methylenetetrahydrofolate reductase (MTHFR) gene, and homozygosity for the 4G allele of the promoter region of the plasminogen activator inhibitor-1 (PAI-1) are potential genetic polymorphisms that have not been consistently associated with increased risk of VT. A case-control study was performed on 192 consecutive unrelated patients referred for evaluation of thrombophilia because of VT and 200 healthy controls. FVL was found in 10.4% of patients compared to 3.0% of controls, while 6.3% of patients were carriers of the PT-20210A allele compared to 2.0% of controls. The adjusted odds ratios (OR) were 5.92 and 4.03 for FVL (P=.001) and the PT-20210A (P=.033), respectively. The prevalence of homozygotes for MTHFR (TT) and PAI-1 (4G/4G) among patients and controls were 13.7% versus 13.0% and 21.6% versus 23.5%, respectively (P=ns). A total of 121 patients underwent a complete screening for FVL, the PT-20210A, protein C (PC), protein S (PS), antithrombin III (ATIII), levels of factor VIII, and antiphospholipid antibodies (aPL). In 59 patients (48.8%) at least one defect was found, being a single defect in 55 and combined defects in 4 patients. Plasma levels of homocysteine (Hcy) were measured in 138 patients and 144 controls. Subjects from both groups carrying the MTHFR-TT variant had higher Hcy levels than those with the normal genotype. Hyperhomocysteinemia (HHcy) by itself is a risk factor for VT (OR 4.92, P<.0001). We conclude that FVL and the PT-20210A are risk factors for VT as well as Hcy levels, but the MTHFR and PAI-1 polymorphisms do not appear to be associated with VT in our country.


Assuntos
Alelos , Fator V/genética , Protrombina/genética , Trombose Venosa/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação
13.
Haematologica ; 86(7): 735-41, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11454529

RESUMO

BACKGROUND AND OBJECTIVES: Thrombosis and pregnancy morbidity are clinical features of the definite antiphospholipid syndrome (APS). These clinical complications are also associated with the presence of inherited thrombophilias. Interactions between acquired and genetic risk factors are becoming increasingly related to a higher thrombotic risk. The aim of our study was to determine the prevalence of four common gene polymorphisms in patients with antiphospholipid antibodies (aPL). DESIGN AND METHODS: A series of 105 consecutive unselected patients with aPL grouped as having APS (n= 69) and not having APS (n= 36) was studied. A control group of 200 healthy subjects was also investigated for the presence of factor V Leiden (FVL), the 20210A allele of the prothrombin (PT-20210A) gene, the thermolabile variant (677TT) of methylenetetrahydrofolate reductase (MTHFR), and the 4G/4G genotype of the plasminogen activator inhibitor (PAI-1) promoter. RESULTS: Two patients who belong to the APS group carried the FVL while PT-20210A was found in 6 patients with APS (8.7%) and in 1 of the non-APS group (2.8%). The prevalence of FVL was similar to that found in the control group whereas PT-20210A was significantly more frequent in APS patients than in normal controls (2.0%, p=0.02). The MTHFR-677TT was found in 22.0%, 15.1% and 13.0%, and the PAI-1 (4G/4G) in 27.5%, 22.8% and 23.5% of APS, non-APS patients and normal controls, respectively. Furthermore, combinations of PT-20210A or FVL with PAI-1 (4G/4G) were significantly more frequent in APS patients (5.8%) than in normal controls (0.5%, p=0.016). This difference was not found between non-APS patients and normal subjects. INTERPRETATION AND CONCLUSIONS: Present data indicate that testing for heritable thrombophilia would be important to identify aPL subjects with an increased risk of developing APS.


Assuntos
Síndrome Antifosfolipídica/genética , Trombofilia/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/etiologia , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Prevalência
15.
Blood Coagul Fibrinolysis ; 10(7): 443-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10695772

RESUMO

The presence of factor V Leiden mutation and the variation of the prothrombin gene 20210GA have been described as additional risk factors for arterial thrombosis when other acquired or metabolic risk factors are present. We report here a 56-year-old man who developed coronary artery disease since 1980 without any known risk factor and underwent a cardiopulmonary by-pass in 1997. In the first month after surgery, he became symptomatic, and an angiography showed complete occlusion of the grafts and some native coronary arteries. Three months after the second cardiopulmonary by-pass, a thrombophilic state was searched, and plasma levels of lipoprotein (a) (LPa) were measured. The patient is heterozygous for factor V Leiden mutation and has the variation 20210GA of the prothrombin gene and high levels of LPa. These findings induced us to add oral anticoagulation to the aspirin treatment, and the patient is in a good condition 11 months later.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias , Fator V/genética , Protrombina/genética , Doença das Coronárias/genética , Doença das Coronárias/fisiopatologia , Doença das Coronárias/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Recidiva , Trombose/genética , Trombose/fisiopatologia
16.
Rev Med Chil ; 121(6): 645-51, 1993 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-8278700

RESUMO

We analyzed retrospectively the clinical course and prognosis of 565 consecutive patients with acute myocardial infarction (AMI), 117 of them with a previous history of diabetes mellitus. Male/female ration was 7.9/2.1 in non diabetics and 7.0/3.0 in diabetics (p < 0.03). Incidence of hypertension and hyperlipidemia was higher in diabetic patients as well as history of congestive heart failure (13.7% vs 6.5 in non diabetics p < 0.01). The type and location of AMI did not differ among groups, however the incidence of congestive heart failure Killip class III-IV was higher in diabetic patients (31.6 vs 21.2%). Peak CPK values were lower in diabetics (1.270 +/- 1.179 vs 1.648 +/- 1.377 U/l p < 0.01). Cardiac mortality was higher one month and one year after AMI in diabetics (17.1 vs 13.6% and 21.4 vs 17.8% respectively, p < 0.01). Univeriate and multivariate analysis identified new bundle branch block, heart failure and advanced age as independent predictors of mortality in both groups of patients. It is concluded that the worst prognosis of diabetic patients with AMI may be related to a previously depressed ventricular function and that appropriate metabolic control and treatment of associated risk factors, could improve the prognosis of diabetics patients with AMI.


Assuntos
Angiopatias Diabéticas/mortalidade , Infarto do Miocárdio/mortalidade , Fatores Etários , Estudos de Casos e Controles , Angiopatias Diabéticas/complicações , Feminino , Humanos , Masculino , Análise Multivariada , Infarto do Miocárdio/complicações , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
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