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1.
Prenat Diagn ; 37(4): 389-398, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28207161

RESUMO

OBJECTIVE: The objective of this study is to investigate the diagnostic value of invasive prenatal diagnosis (PD) of congenital cytomegalovirus (CMV) infection from amniotic fluid (AF) and fetal blood (FB). METHODS: A retrospective study was conducted on 115 pregnancies with CMV primary infection. A total of 111 AF and 106 FB samples were investigated for various virological and non-virological markers. Detailed ultrasound examinations were performed at time of PD. RESULTS: Overall sensitivity of CMV PCR in FB (75.6%; 95%CI 60-87) and AF (72.7%; 95%CI 57-85) was comparable. In women with amniocentesis >8 weeks between seroconversion and PD, we did not observe significant differences between amniocentesis performed ≥17 + 0 (sensitivity 90.9%; 95%CI 71-99) and ≥20 + 0 gestational weeks (sensitivity 90.0%; 95%CI 68-99). Virological markers in FB were higher in symptomatic compared with asymptomatic fetuses (p < 0.05). No significant differences were observed for non-virological markers. However, platelet counts <120 × 10e9/L and beta-2 microglobulin values >14 mg/L were more frequently found in fetuses with severe ultrasound abnormalities compared with fetuses with no or mild abnormalities (p < 0.001). CONCLUSION: Optimal timing of amniocentesis in women with primary infection in early gestation should be reevaluated in a prospective study. Analysis of FB markers may be beneficial in the individual management of pregnant women with confirmed congenital CMV infection. © 2017 John Wiley & Sons, Ltd.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Doenças Fetais/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Diagnóstico Pré-Natal , Adulto , Amniocentese , Infecções por Citomegalovirus/congênito , Feminino , Sangue Fetal/virologia , Doenças Fetais/virologia , Alemanha , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Valor Preditivo dos Testes , Gravidez , Diagnóstico Pré-Natal/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
3.
J Cell Biol ; 103(3): 1109-19, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3528169

RESUMO

We have examined the adhesion of primary Sertoli cells to a seminiferous tubule basement membrane (STBM) preparation in vitro. The STBM isolation procedure (Watanabe, T.K., L.J. Hansen, N.K. Reddy, Y.S. Kanwar, and J.K. Reddy, 1984, Cancer Res., 44:5361-5368) yields segments of STBM that retain their histotypic form in both three-dimensional tubular geometry and ultrastructural appearance. The STBM sleeves contain two laminae: a thick, inner basal lamina that was formed in vivo between Sertoli cells and peritubular myoid cells; and a thinner, outer basal lamina that was formed between myoid cells and sinusoidal endothelial cells. Characterization by immunofluorescence and SDS PAGE revealed that the isolated STBM retained fibronectin, laminin, and putative type IV collagen among its many components. When the STBM sleeves were gently shaken with an enriched fraction of primary Sertoli cells, the Sertoli cells bound preferentially to the lumenal basal lamina at the ends of the STBM sleeves. Few Sertoli cells bound to either the outer basal lamina of the STBM sleeves or to vascular extracellular matrix material which contaminated the STBM preparation. 3T3 cells, in contrast, bound to all surfaces of the STBM sleeves. Pretreatment of the STBM sleeves with proteases, 0.1 M Na metaperiodate, 4 M guanidine HCl, or heating to 80 degrees-90 degrees C inhibited lumenal Sertoli cell binding, but binding was not inhibited by chondroitinase ABC, heparinase, hyaluronidase, or 4 M NaCl. The lumenal Sertoli cell binding occurred in the presence or absence of added soluble laminin, but not fibronectin. The addition of soluble laminin, but not fibronectin, restored random binding of Sertoli cells to trypsinized STBM sleeves. Our in vitro model system indicates that Sertoli cells recognize differences in two basal laminae produced in vivo on either side of myoid cells.


Assuntos
Membrana Basal/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Animais , Membrana Basal/efeitos dos fármacos , Membrana Basal/ultraestrutura , Adesão Celular , Colágeno/análise , Matriz Extracelular/análise , Fibronectinas/análise , Imunofluorescência , Laminina/análise , Masculino , Peptídeo Hidrolases/farmacologia , Ratos , Testículo/efeitos dos fármacos , Testículo/ultraestrutura
4.
J Cell Biol ; 100(5): 1558-69, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-3988801

RESUMO

Hepatocytes of estradiol-treated rats, which express many low density lipoprotein receptors, rapidly accumulate intravenously injected low density lipoprotein in multivesicular bodies (MVBs). We have isolated MVBs and Golgi apparatus fractions from livers of estradiol-treated rats. MVB fractions were composed mainly of large vesicles, approximately 0.55 micron diam, filled with remnantlike very low density lipoproteins, known to be taken up into hepatocytes by receptor-mediated endocytosis. MVBs also contained numerous small vesicles, 0.05-0.07 micron in diameter, and had two types of appendages: one fingerlike and electron dense and the other saclike and electron lucent. MVBs contained little galactosyltransferase or arylsulfatase activity, and content lipoproteins were largely intact. Very low density lipoproteins from Golgi fractions, which are derived to a large extent from secretory vesicles, were larger than those of MVB fractions and contained newly synthesized triglycerides. Membranes of MVBs contained much more cholesterol and less protein than did Golgi membranes. We conclude that two distinct lipoprotein-filled organelles are located in the bile canalicular pole of hepatocytes. MVBs, a major prelysosomal organelle of low density in the endocytic pathway, contain remnants of triglyceride-rich lipoproteins, whereas secretory vesicles of the Golgi apparatus contain nascent very low density lipoproteins.


Assuntos
Fígado/ultraestrutura , Organoides/ultraestrutura , Animais , Fracionamento Celular , Endocitose , Complexo de Golgi/ultraestrutura , Membranas Intracelulares/análise , Ponto Isoelétrico , Lipoproteínas VLDL/metabolismo , Masculino , Microscopia Eletrônica , Ratos
5.
Mol Cell Biol ; 21(8): 2755-66, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283255

RESUMO

Cyclin-dependent kinase 2 (Cdk2) is essential for initiation of DNA synthesis in higher eukaryotes. Biochemical studies in Xenopus egg extracts and microinjection studies in human cells have suggested an additional function for Cdk2 in activation of Cdk1 and entry into mitosis. To further examine the role of Cdk2 in human cells, we generated stable clones with inducible expression of wild-type and dominant-negative forms of the enzyme (Cdk2-wt and Cdk2-dn, respectively). Both exogenous proteins associated efficiently with endogenous cyclins. Cdk2-wt had no apparent effect on the cell division cycle, whereas Cdk2-dn inhibited progression through several distinct stages. Cdk2-dn induction could arrest cells at the G1/S transition, as previously observed in transient expression studies. However, under normal culture conditions, Cdk2-dn induction primarily arrested cells with S and G2/M DNA contents. Several observations suggested that the latter cells were in G2 phase, prior to the onset of mitosis: these cells contained uncondensed chromosomes, low levels of cyclin B-associated kinase activity, and high levels of tyrosine-phosphorylated Cdk1. Furthermore, Cdk2-dn did not delay progression through mitosis upon release of cells from a nocodazole block. Although the G2 arrest imposed by Cdk2-dn was similar to that imposed by the DNA damage checkpoint, the former was distinguished by its resistance to caffeine. These findings provide evidence for essential functions of Cdk2 during S and G2 phases of the mammalian cell cycle.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Fase G2/fisiologia , Mutação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fase S/fisiologia , Sequência de Bases , Proteína Quinase CDC2/metabolismo , Células Clonais , Quinase 2 Dependente de Ciclina , Ciclinas/metabolismo , DNA/genética , DNA/metabolismo , Dano ao DNA , Primers do DNA/genética , Fase G1/genética , Fase G1/fisiologia , Fase G2/genética , Expressão Gênica , Genes Dominantes , Humanos , Mitose/genética , Mitose/fisiologia , Fase S/genética , Transfecção
6.
Mol Cell Biol ; 19(5): 3916-28, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10207115

RESUMO

The tumor suppressor p16(INK4a) inhibits cyclin-dependent kinases 4 and 6. This activates the retinoblastoma protein (pRB) and, through incompletely understood events, arrests the cell division cycle. To permit biochemical analysis of the arrest, we generated U2-OS osteogenic sarcoma cell clones in which p16 transcription could be induced. In these clones, binding of p16 to cdk4 and cdk6 abrogated binding of cyclin D1, p27(KIP1), and p21(WAF1/CIP1). Concomitantly, the total cellular level of p21 increased severalfold via a posttranscriptional mechanism. Most cyclin E-cdk2 complexes associated with p21 and became inactive, expression of cyclin A was curtailed, and DNA synthesis was strongly inhibited. Induction of p21 alone, in a sibling clone, to the level observed during p16 induction substantially reproduced these effects. Overexpression of either cyclin E or A prevented p16 from mediating arrest. We then extended these studies to HCT 116 colorectal carcinoma cells and a p21-null clone derived by homologous recombination. In the parental cells, p16 expression also augmented total cellular and cdk2-bound p21. Moreover, p16 strongly inhibited DNA synthesis in the parental cells but not in the p21-null derivative. These findings indicate that p21-mediated inhibition of cdk2 contributes to the cell cycle arrest imposed by p16 and is a potential point of cooperation between the p16/pRB and p14(ARF)/p53 tumor suppressor pathways.


Assuntos
Apoptose/genética , Quinases relacionadas a CDC2 e CDC28 , Proteínas de Ciclo Celular , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Replicação do DNA , Regulação da Expressão Gênica , Humanos , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/metabolismo , Polirribossomos , Ligação Proteica , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
7.
Oncogene ; 19(13): 1613-22, 2000 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-10763818

RESUMO

The tumor suppressor p16INK4a is a potent mediator of cell cycle arrest in transient expression studies, is induced in senescing cells, and can impose morphological features of senescence. Nonetheless, it is unclear whether p16INK4a can block cell proliferation irreversibly. We explored this issue using osteogenic sarcoma cell clones with inducible p16INK4a expression. Induction of p16INK4a for 1 day arrested most cells in G1 phase. If the induction was then interrupted, p16INK4a levels returned to baseline and robust growth resumed within 3-5 days. When p16INK4a was induced for 6 days DNA synthesis remained strongly inhibited and the cells acquired morphological features of senescence. Moreover, if p16INK4a induction was interrupted at this point and the cells were followed for 12 more days, most cells retained these morphologic features and either failed to divide or died. This occurred despite the prompt return of p16INK4a expression and retinoblastoma protein phosphorylation toward baseline levels. In fact, some senescing cells appeared to enter S phase. These results demonstrate that a sustained period of p16INK4a expression is sufficient in this setting to impose a durable block to cell proliferation and that this state becomes independent of p16INK4a expression, hypophosphorylation of pRB, or a strict G1 arrest.


Assuntos
Proteínas de Transporte/fisiologia , Senescência Celular/fisiologia , Fase G1 , Genes p16 , Neoplasias Ósseas/patologia , Divisão Celular , Senescência Celular/genética , Meios de Cultura Livres de Soro , Inibidor p16 de Quinase Dependente de Ciclina , Replicação do DNA , DNA de Neoplasias/biossíntese , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Nocodazol/farmacologia , Osteossarcoma/patologia , Fosforilação , Processamento de Proteína Pós-Traducional , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas
8.
Oncogene ; 12(6): 1239-45, 1996 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-8649826

RESUMO

We and others have recently shown that p16 can potently and specifically inhibit progression through the G1 phase of the replicative cycle in cells that express the retinoblastoma protein (pRB). However, none of these studies examined cell types in which p16 has been firmly implicated in tumorigenesis. We predicted that such cells would show sensitivity to p16 inhibition, perhaps conferred by proteins in addition to or other than pRB. Intragenic, inactivating mutations of p16 have been found at significant frequency in primary tumors derived from squamous epithelial cells of the esophagus (ESCC). We therefore examined p16 function in ESCC lines and in primary squamous epithelial cells cultured from mouse skin. We find that seven of eight ESCC lines tested are inhibited by p16 and fail to express the protein endogenously. The lone p16-resistant line expresses endogenous p16 but lacks functional pRB. Primary squamous epithelial cells are also inhibited by p16. These data suggest that squamous epithelial cells are generally sensitive to inhibition by a regulatory pathway that involves p16 and pRB, and that, by the time of establishment in culture, there is nearly universal inactivation of this pathway in ESCCs.


Assuntos
Carcinoma de Células Escamosas/patologia , Proteínas de Transporte/fisiologia , Transformação Celular Neoplásica/patologia , Queratinócitos/fisiologia , Neoplasias Cutâneas/patologia , Células 3T3/patologia , Células 3T3/fisiologia , Animais , Proteínas de Transporte/genética , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina , Células Epiteliais , Epitélio/fisiologia , Éxons , Humanos , Queratinócitos/citologia , Camundongos , Camundongos Endogâmicos SENCAR , Microinjeções , Proteína do Retinoblastoma/fisiologia , Sensibilidade e Especificidade , Pele/citologia , Fenômenos Fisiológicos da Pele
9.
Biochim Biophys Acta ; 1090(2): 223-9, 1991 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-1932114

RESUMO

Northern blot analysis revealed that metallothionein (MT) mRNAs accumulate after inhibition of protein synthesis with cycloheximide (CHX) in primary cultures of chick embryo hepatocytes and fibroblasts, as well as in an established mouse hepatoma cell line. Inhibition of RNA synthesis with actinomycin D (AMD) led to rapid loss of MT mRNAs in these cells, whereas CHX dramatically retarded the rate of MT mRNA decay (t1/2 greater than 24 h). These results suggest that CHX causes MT mRNA accumulation primarily by increasing stability of MT mRNA. Thus, changes in MT mRNA turn-over rates may play an important role in regulating the accumulation of MT mRNA. The half-lives of MT mRNAs in chicken and mouse cells were determined by oligodeoxyribonucleotide excess solution hybridization with RNA samples extracted after different periods of exposure to AMD. The half-life of chicken MT (cMT) mRNA in uninduced chicken embryo hepatocytes was 3.6 h. Induction of cMT mRNA by pretreatment of these cells with zinc (Zn) prior to exposure to AMD, did not alter the half-life of cMT mRNA significantly. In contrast, cadmium (Cd) induction led to a 2.5-fold increase in the stability of this mRNA. In uninduced chicken embryo fibroblasts, cMT mRNA levels were too low to allow accurate determination of half-life using the methods employed here. However, the half-life of this mRNA in Zn-induced chicken embryo fibroblasts was 6.2 h, whereas it was 9.3 h in Cd-induced cells. Thus, the turn-over rate of cMT mRNA after Cd-induction is very similar in chick embryo fibroblasts and hepatocytes. These data suggest that the accumulation of MT mRNA in chicken cells may reflect, in part, metal-specific effects on MT mRNA stability. The half-lives of mouse MT-I and MT-II (mMT-I and mMT-II) mRNAs in uninduced BNL hepatoma cells were identical (9.2 h), and were not effectively altered after induction by metals (Zn, Cd) or interleukin-1 beta (IL-1 beta). However, mMT mRNAs in pachytene spermatocytes and round spermatids, freshly isolated from the adult testes, were 2.2- to 4.5-fold more stable than in hepatoma cells. These results suggest that cell-type specific accumulation of mMT mRNAs may be regulated, in part, by mRNA stability.


Assuntos
Metalotioneína/genética , RNA Mensageiro/metabolismo , Animais , Sequência de Bases , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Embrião de Galinha , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Regulação da Expressão Gênica , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/isolamento & purificação
10.
Circulation ; 104(12 Suppl 1): I336-43, 2001 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-11568079

RESUMO

BACKGROUND: Inducible nitric oxide synthase (iNOS) is expressed and is functionally active in the presence of transplant arteriosclerosis. However, the early involvement of iNOS in alterations of microvascular endothelial function in the absence of preexisting lesions remains unclear; this information would be of prognostic value. We studied the course of iNOS mRNA expression, transcardiac nitric oxide production, and their potential association with microvascular coronary endothelial dysfunction in human cardiac allografts. METHODS AND RESULTS: A total of 42 patients were studied at 1, 6, and 12 months after heart transplantation. Microvascular coronary flow velocity reserve (CFVR) was tested in an endothelium-dependent (acetylcholine) and -independent manner (adenosine) using a Doppler flow wire. Endomyocardial iNOS expression was determined by reverse transcription polymerase chain reaction. iNOS protein and nitrotyrosine levels were detected by immunohistochemistry. Transcardiac plasma nitrite/nitrate (NOx) levels were measured by the Griess reaction. CFVR was impaired in 26.1% of patients (n=11) at 1 month and in 31% of patients (n=13) at 12 months after heart transplantation. Patients who developed impaired CFVR in the first year showed a significant increase in iNOS gene expression. Patients with impairment of CFVR 1 month after heart transplantation had higher levels of iNOS mRNA than patients with a normal CFVR. Patients with an initial impairment of CFVR who did not improve over time presented with significantly higher iNOS mRNA levels. iNOS protein and nitrotyrosine were expressed in the endomyocardial vessels of patients with impaired CFVR. Transcardiac NOx release was higher in patients with impaired CFVR. CONCLUSIONS: In human cardiac allografts, microvascular endothelial dysfunction is associated with an enhanced endomyocardial iNOS mRNA expression and higher transcardiac NOx production and is accompanied by the expression of nitrotyrosine protein, suggesting peroxynitrite plays a role in the disease process. The data from the present study suggest an important role for the iNOS/nitric oxide pathway in the regulation of microvascular function in the absence of preexisting atherosclerotic lesions.


Assuntos
Vasos Coronários/metabolismo , Endotélio Vascular/metabolismo , Transplante de Coração , Miocárdio/metabolismo , Óxido Nítrico Sintase/biossíntese , Tirosina/análogos & derivados , Acetilcolina/farmacologia , Adolescente , Adulto , Idoso , Biópsia , Demografia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Microcirculação/efeitos dos fármacos , Microcirculação/metabolismo , Pessoa de Meia-Idade , Miocárdio/patologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Valor Preditivo dos Testes , Estudos Prospectivos , RNA Mensageiro/biossíntese , Tirosina/metabolismo , Sistema Vasomotor/efeitos dos fármacos
11.
Mol Endocrinol ; 5(5): 628-36, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2072922

RESUMO

Northern blotting, in situ hybridization, and oligodeoxyribonucleotide excess solution hybridization were used to quantitate metallothionein-I (MT-I) and MT-II mRNAs in mouse testes. Testes from sexually mature adults contained high levels of both MT mRNAs (approximately 10-fold higher than those in control adult liver). Testicular MT mRNA levels were age dependent, being low the first 2 weeks after birth and increasing slowly thereafter to maximal levels in the adult (by 9 weeks after birth). In the adult testis, in situ hybridization indicated that only cells within the adluminal compartment (germ cells) of the seminiferous tubules contain high levels of MT mRNA. The appearance of cells containing elevated levels of MT mRNA during development was delayed from the onset of spermatogenesis. In situ hybridization suggested that MT mRNA accumulates after the initial differentiation of primary spermatocytes and is maintained in spermatids. Pachytene spermatocytes (PSC) and round spermatids (RTD) isolated from adult testes contained both MT-I and MT-II mRNAs in levels equivalent to those found in zinc-treated hepatocytes, whereas very low levels of MT mRNA were detected in isolated Sertoli cells (ST). In situ hybridization suggested that MT mRNA was present at only basal levels in interstitial, spermatogonial, and mature sperm cells at all developmental stages examined. Northern blot and in situ hybridization to sulfated glycoprotein-2 (SGP-2) mRNA, a ST-specific transcript, showed that SGP-2 mRNA is high in the testis of 1-week-old mice and decreases gradually to a lower level in the adult. In situ detection of this mRNA was consistent with the location of ST in the testis. SGP-2 mRNA was abundant in ST and rare in PSC and RTD preparations. Analysis of pulse-labeled proteins from isolated PSC and RTD indicated that these cells actively synthesize MT-I and MT-II. The high levels of MT mRNA in adult testes were not increased substantially after systemic injection of cadmium, zinc, or bacterial lipopolysaccharide. In marked contrast, these treatments led to dramatically increased levels of hepatic and ovarian MT mRNA. This study establishes that the MT genes are actively expressed in a developmentally regulated fashion in the male germ cells of the mouse. This suggests a role for MT in the process of spermatogenesis.


Assuntos
Células Germinativas/metabolismo , Metalotioneína/genética , RNA Mensageiro/metabolismo , Testículo/metabolismo , Animais , Sequência de Bases , Cádmio/farmacologia , Genes , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Espermátides/metabolismo , Espermatócitos/metabolismo , Testículo/crescimento & desenvolvimento , Zinco/farmacologia
12.
Gynakol Geburtshilfliche Rundsch ; 45(1): 39-43, 2005 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-15644639

RESUMO

OBJECTIVE: Since mumps infection is endemic, the occurrence of acute mumps infection during pregnancy is rare. As a result, data on the possible negative consequences of acute mumps infection on pregnancy outcome are limited. PATIENTS AND METHODS: The clinical diagnosis of acute mumps infection was serologically confirmed in 79 pregnant women between January 1985 and December 2002. Data on pregnancy outcome were obtained from the gynaecologist or obstetrician. Cord blood from 26 of the 57 live-born infants was investigated for mumps-specific IgM and IgG antibodies by enzyme-linked immunoassay. RESULTS: Sixty-two patients were prospectively followed up with respect to pregnancy outcome. Two of the 62 pregnancies were electively terminated. The overall rate of fetal loss was 6.6% (4/60). Only 2 cases of spontaneous abortion occurred during the first trimester. However, all 4 spontaneous abortions occurred in women who had contracted mumps infection during the first trimester. The time interval between mumps infection and fetal loss varied widely. The median gestational age at delivery was 40 weeks. Only 2 of the 57 live-born infants (3.5%) were delivered before completion of the 37th week of pregnancy. Mumps-specific IgM anti-bodies were not detected in any of the 26 cord blood samples tested. CONCLUSION: The lack of mumps-specific antibodies in the cord blood samples tested suggests that prenatal mumps infection did not occur. The frequency of premature birth and spontaneous abortion following mumps infection in pregnancy does not appear to be increased over normal levels.


Assuntos
Aborto Espontâneo/epidemiologia , Caxumba/epidemiologia , Trabalho de Parto Prematuro/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Doença Aguda , Adolescente , Adulto , Anticorpos Antivirais/sangue , Estudos Transversais , Feminino , Sangue Fetal/imunologia , Morte Fetal/epidemiologia , Seguimentos , Humanos , Recém-Nascido , Masculino , Vírus da Caxumba/imunologia , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Prospectivos , Risco , Medição de Risco
13.
Endocrinology ; 133(1): 389-96, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8319585

RESUMO

Enriched fractions of spermatogenic cells were isolated by unit gravity sedimentation and analyzed both for the presence of secreted tumor necrosis factor-alpha (TNF alpha) in vitro by bioassay and for the presence of TNF alpha mRNA by Northern blot analysis. Small quantities of bioactive TNF alpha were consistently detected in medium conditioned by round spermatid fractions. Both pachytene spermatocyte and round spermatid fractions contained RNA that hybridized with murine cDNA probes for TNF alpha, with pachytene spermatocytes containing a normal 1.9-kilobase (kb) transcript, while round spermatids contained principally an approximately 2.8-kb transcript. Both the normal size transcript and the larger haploid-specific transcript were enriched when total RNA from pachytene spermatocyte and round spermatid fractions was passed through an oligo(dT) column. The normal 1.9-kb transcript within pachytene spermatocytes could be induced by exposing the spermatogenic cells to lipopolysaccharides in vitro, yet the approximately 2.8-kb transcript within round spermatids appeared uninduced by LPS treatment. In situ hybridization for the TNF alpha message by using digoxigenin label antisense TNF alpha riboprobe labeled pachytene spermatocytes, round spermatids, and presumptive interstitial macrophages. Spermatogonia and elongating spermatids as well as other interstitial cells were unlabeled or very lightly labeled. Hybridization of 16-day-old prepuberal testis resulted in the labeling of spermatocytes and presumptive interstitial macrophages. RNA from Sertoli cells, but not pachytene spermatocytes or round spermatids, hybridized with human TNF alpha receptor p60 probe in Northern blot analysis. These results are consistent with the working hypothesis that spermatids release TNF alpha, which is detected by Sertoli cells and may serve as a paracrine factor, regulating an as yet unidentified process in spermatogenesis.


Assuntos
Expressão Gênica , Espermatozoides/metabolismo , Fator de Necrose Tumoral alfa/genética , Animais , Northern Blotting , Células Cultivadas , Meios de Cultivo Condicionados , Hibridização In Situ , Células Intersticiais do Testículo/química , Fígado/química , Masculino , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/análise , Células de Sertoli/química , Espermátides/química , Espermátides/metabolismo , Espermatozoides/química , Testículo/química , Fator de Necrose Tumoral alfa/análise
14.
Cancer Lett ; 100(1-2): 31-6, 1996 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-8620450

RESUMO

Spontaneous testicular teratomas which develop at a high rate in 129/Sv-Sl/+ mice are thought to be derived from germ cells. The teratomas present initially as groups of atypical germ-like cells within seminiferous cords of the 15.5 days post coitum (dpc) embryonic testes. These pluripotent teratoma stem cells are capable of differentiating into many kinds of tissues in adult mice. In this immunohistochemical study, we have examined the testes of 129/Sv-Sl/+ mice to determine whether the teratoma cells which developed in these gonads retain the nuclear antigen GCNA1. GCNA1 is a 110 kDa mouse Germ Cell Nuclear Antigen recognized by a rat monoclonal antibody 10D9G11. GCNA1 is expressed in mouse germ cells after they migrate into the genital ridge (11.5 dpc), throughout embryonic development until postnatally germ cells arrive at the diplotene/dictyate stage of the first meiotic division, when it is no longer expressed. Early foci (16.5 dpc) of teratoma stem cells in 129/Sv-Sl/+ mice strongly express GCNA1, but down regulate GCNA1 expression by 19.5 dpc. The loss of GCNA1 expression from teratoma stem cells late in embryonic development is in contrast to embryonic gonocytes which retain GCNA1 expression throughout fetal development. All postnatal undifferentiated and differentiated teratoma cells did not appear to express GCNA1. The expression of the germ cell specific nuclear antigen GCNA1 in early teratoma stem cells further demonstrated that the testicular teratomas originate from early germ cells. The stronger reaction of monoclonal antibody 10D9G11 to GCNA1 within early teratoma cells compared to normal germ cells makes GCNA1 useful in identifying early embryonic tumor foci.


Assuntos
Antígenos de Neoplasias/biossíntese , Teratoma/metabolismo , Neoplasias Testiculares/metabolismo , Animais , Diferenciação Celular/fisiologia , Núcleo Celular/metabolismo , Epitopos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Endogâmicos , Espermatozoides/metabolismo , Teratoma/patologia , Neoplasias Testiculares/patologia
15.
Environ Health Perspect ; 104(1): 68-76, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8834864

RESUMO

Exposure to low levels of cadmium reduces fertility. In male mice spermatogenesis is highly sensitive to cadmium, whereas in females the peri-implantation period of pregnancy is sensitive. To examine the potential roles of the cadmium-binding protein, metallothionein (MT), in the reproductive toxicology of cadmium, we examined a transgenic mouse strain that overexpresses metallothionein-I (MT-I). These mice had dramatically increased steady-state levels of MT-I mRNA and MT in the testes and in the female reproductive tract during the peri-implantation period of pregnancy, and this overexpression occurred in a cell-specific and temporally regulated manner similar to that of the endogenous MT-I gene. Transgenic and control males were injected with cadmium, and the histology of the testes was examined. An injection of 7.5 mumol Cd/kg had no effect on histology of the testes in either transgenic or control mice. In contrast, an injection of 10 mumol Cd/kg caused rapid changes in the histology of the testes and resulted in pronounced testicular necrosis in both control and transgenic mice. Female transgenic and control mice were mated and then injected with cadmium (30-45 mumol Cd/kg) on the day of blastocyst implantation (day 4). In both of these groups, injection of cadmium reduced pregnancy rate, and no dramatic protection was afforded by maternal and/or embryonic overexpression of MT. Thus, overexpression of MT-I does not significantly protect against either of these cadmium-induced effects on fertility.


Assuntos
Cloreto de Cádmio/metabolismo , Cloreto de Cádmio/toxicidade , Metalotioneína/metabolismo , Reprodução/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Animais , Feminino , Masculino , Metalotioneína/análise , Metalotioneína/genética , Camundongos , Camundongos Transgênicos , Gravidez , RNA Mensageiro/análise , Testículo/química , Testículo/patologia , Testes de Toxicidade , Útero/química , Útero/efeitos dos fármacos
16.
Environ Health Perspect ; 105 Suppl 5: 1297-300, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9400741

RESUMO

Nitric oxide (NO) is suggested to play a role in mediating pulmonary injury. However, interspecies differences appear to exist in the ability of alveolar macrophages (AM) to express the inducible nitric oxide synthase (iNOS) and to generate NO. The purpose of this study was to compare iNOS expression and NO production by rat, hamster, monkey, and human AM using the identical experimental conditions in vitro. As AM donors, CD rats, Syrian golden hamsters, cynomolgus monkeys, and nonsmoking, healthy human volunteers were used. The AM were obtained by bronchoalveolar lavage and stimulated in vitro with various concentrations and combinations of lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). The oxidation product of NO, nitrite, was measured in the AM supernatant by the Griess reaction. The expression of iNOS in AM was detected using immunocytochemistry and immunoblotting. The expression of iNOS mRNA was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR). Rat AM, stimulated with either LPS or IFN-gamma, produced nitrite in a time- and dose-dependent manner. Combination of LPS and IFN-gamma resulted in a significantly enhanced nitrite formation. However, none of the treatments was able to induce hamster, monkey, or human AM to release measurable amounts of nitrite. Whereas expression of iNOS protein was only detected in stimulated rat AM, expression of iNOS mRNA was found in unstimulated and stimulated rat AM, slightly in stimulated hamster AM, but not in monkey and human AM. In conclusion, our findings point to distinct regulatory mechanisms of the NO pathway in AM from these four different species.


Assuntos
Macrófagos Alveolares/metabolismo , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico/biossíntese , Adulto , Animais , Western Blotting , Líquido da Lavagem Broncoalveolar , Células Cultivadas , Cricetinae , Humanos , Imuno-Histoquímica , Macaca fascicularis , Macrófagos Alveolares/enzimologia , Mesocricetus , Óxido Nítrico Sintase Tipo II , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie
17.
Int J Oncol ; 15(2): 209-16, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10402229

RESUMO

Cyclin-dependent kinase inhibitors are potent suppressors of cell growth and have been proposed as targets for gene replacement therapy in cancer. Expression of either p16INK4a or p21WAF1 protected cells from the cytotoxic effects of the topoisomerase II inhibitor, etoposide. A lower level of p53 was induced in CDK inhibitor-expressing etoposide-exposed cells suggesting that protection may be due to lower levels of DNA damage in the growth arrested cells. Exposure of human osteosarcoma cells to either p16INK4a or p21WAF1 prior to and during etoposide therapy protected cells against etoposide-induced cell death. Infection of the cells by Ad-p16INK4a or Ad-p21WAF1 following exposure to etoposide resulted in loss of the protective effect with evidence of enhanced growth inhibition. The results suggest that the schedule of administration of DNA damaging etoposide chemotherapy and cell cycle inhibitory therapy is a major determinant of the resulting cytotoxicity.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Etoposídeo/uso terapêutico , Terapia Genética/métodos , Neoplasias Ósseas/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Dano ao DNA , Esquema de Medicação , Genes p16 , Humanos , Osteossarcoma/tratamento farmacológico , Inibidores da Topoisomerase II
18.
Shock ; 12(5): 329-34, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10565606

RESUMO

Transient sublethal hyperthermia and the recovery from this exposure to heat (heat shock preconditioning) provides a cytoprotective effect on oxidative insults through an intracellular protective response, heat shock response. The impact of heat shock preconditioning on hepatic microvascular failure, which is a causative determinant of ischemia/reperfusion-induced injury of the liver, was investigated by using intravital fluorescence microscopy. In Sprague-Dawley rats, normothermic ischemia was induced by totally clamping the hepatoduodenal ligament for 20 min, followed by 120 min of reperfusion. Heat shock preconditioning was performed by whole-body hyperthermia (42 degrees C for 15 min) and subsequent 48 h recovery. In accordance with the prominent induction of heat shock protein 70 in the liver tissue, the postischemic decrease in sinusoidal perfusion rate and sinusoidal diameter, and the postischemic increase in the number of stagnant leukocytes in sinusoids and adherent leukocytes in postsinusoidal venules were significantly attenuated in the heat shock-treated animals. Furthermore, liver enzyme release (glutamate pyruvate transaminase and alpha-glutathione S-transferase) was significantly reduced and postischemic deterioration of bile production was attenuated. The 7-day survival rate after 20-minute ischemia was significantly improved from 50% to 80% (heat shock-nontreated group vs. heat shock-treated group, P < 0.05). These results indicate that heat shock preconditioning attenuates ischemia/reperfusion-induced hepatic injury by preventing postischemic microvascular disturbances, and that its protective effect is circumstantially associated with the concomitant induction of heat shock protein 70.


Assuntos
Resposta ao Choque Térmico , Fígado/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Alanina Transaminase/metabolismo , Animais , Bile/metabolismo , Pressão Sanguínea , Glutationa Transferase/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Fígado/metabolismo , Fígado/ultraestrutura , Masculino , Microcirculação , Microscopia de Fluorescência/métodos , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/prevenção & controle , Taxa de Sobrevida , Temperatura
19.
J Thorac Cardiovasc Surg ; 76(1): 83-9, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-661372

RESUMO

A review of the literature on patients who have survived wounds traversing two or more cardiac chambers is presented and two further cases are documented. The inital management of the patient should be directed toward control of hemorrhage or treatment of cardica tamponade or both. Cardiopulmonary bypass is helpful in repair of many intracardiac defects but is not absolutely essential for survival. Surface myocardial wounds should be sutured during the initial procedure to allow for immediate survival. A subsequent procedure may be indicated to correct intracardiac defects. Repair of injuries to the mitral and aortic valves should be directed at an attempt to reconstruct the damaged valve. If this is impossible, a prosthetic valve should be inserted. Injuries to the tricuspid and pulmonic valves probably warrant a conservative approach. Septal defects can be treated easily with Dacron patches or primary suture closure. Postoperative complications include all of those commonly seen with thoracic procedures, but infection is less prominent than one would anticipate, even when prostheses have been implanted. With early, aggressive management it is anticipated that more survivors of these serious wounds will be recorded.


Assuntos
Átrios do Coração/lesões , Traumatismos Cardíacos/cirurgia , Ventrículos do Coração/lesões , Ferimentos por Arma de Fogo/cirurgia , Adolescente , Parada Cardíaca/etiologia , Traumatismos Cardíacos/complicações , Traumatismos Cardíacos/mortalidade , Septos Cardíacos/lesões , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/lesões , Derrame Pericárdico/etiologia , Valva Tricúspide/lesões , Ferimentos por Arma de Fogo/complicações
20.
J Clin Virol ; 11(2): 93-102, 1998 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-9785210

RESUMO

BACKGROUND: As primary cytomegalovirus (CMV) infection in pregnancy may be associated with severe fetal outcome, the serological differentiation of primary infection from recurrent or previous infection is of major importance. OBJECTIVES: This differentiation was attempted with a CMV IgG enzyme immunoassay (EIA), which investigated the differential IgG immune response to recombinant proteins p52 and pp150. To express the IgG reactivity to either protein a ratio was calculated by OD p52/OD pp150. STUDY DESIGN: Serial samples from groups of pregnant women with primary infection (n = 18) were compared to those with recurrent (n = 7) or previous CMV infection (n = 189). RESULTS: In primary infected women a predominant IgG response to p52 (p52 alone or ratio > or = 1.5) was observed in early sera less than 4 weeks after seroconversion, whereas the IgG response to recombinant protein pp150 was delayed and appeared after 2-7 weeks. Women with secondary and those with past infection had either IgG antibodies to pp150 alone or a ratio of less than 1.5 in 85 and 89.1% respectively with no remarkable change of ratio over time. CONCLUSIONS: The IgG recombinant EIA was shown to be a useful supplementary assay for differentiation of primary up to 8 weeks after seroconversion from recurrent or past infections.


Assuntos
Antígenos Virais/imunologia , Infecções por Citomegalovirus/imunologia , Técnicas Imunoenzimáticas/métodos , Complicações Infecciosas na Gravidez/imunologia , Proteínas Recombinantes/imunologia , Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/virologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Gravidez , Complicações Infecciosas na Gravidez/virologia , Resultado da Gravidez , Recidiva , Sensibilidade e Especificidade , Proteínas Virais/genética , Proteínas Virais/imunologia
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