Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Orphanet J Rare Dis ; 17(1): 94, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236361

RESUMO

BACKGROUND/OBJECTIVE: Arginase 1 Deficiency (ARG1-D) is a rare inherited metabolic disease with progressive, devastating neurological manifestations with early mortality and high unmet need. Information on prevalence is scarce and highly variable due to limited newborn screening (NBS) availability, variability of arginine levels in the first days of life, and high rates of misdiagnosis. US birth prevalence was recently estimated via indirect methods at 1.1 cases per million live births. Due to the autosomal recessive nature of ARG1-D we hypothesize that the global prevalence may be more accurately estimated using genetic population databases. METHODS: MEDLINE and EMBASE were systematically searched for previously reported disease variants. Disease variants in ARG1-D were annotated wherever possible with allele frequencies from gnomAD. Ethnicity-specific prevalence was calculated using the Hardy-Weinberg equation and applied to generate country-specific carrier frequencies for 38 countries. Finally, documented consanguinity rates were applied to establish a birth prevalence for each country. RESULTS: 133 of 228 (58%) known causative alleles were annotated with ethnic-specific frequencies. Global birth prevalence for ARG1-D was estimated at 2.8 cases per million live births (country-specific estimates ranged from 0.92 to 17.5) and population prevalence to be 1.4 cases per million people (approximately 1/726,000 people). Birth prevalence estimates were dependent on population demographics and consanguinity rate. CONCLUSION: Birth prevalence of ARG1-D based on genetic database analysis was estimated to be more frequent than previous NBS studies have indicated. There was a higher degree of confidence in North American and European countries due to availability of genetic databases and mutational analysis versus other regions. These findings suggest the need for greater disease education around signs and manifestations of ARG1-D, as well as more widespread testing and standardization of screening for this severe disease in order to appropriately identify patients prior to disease progression.


Assuntos
Arginase , Hiperargininemia , Alelos , Arginase/genética , Bases de Dados Genéticas , Frequência do Gene , Humanos , Hiperargininemia/epidemiologia , Hiperargininemia/genética , Recém-Nascido , Prevalência
2.
Artigo em Inglês | MEDLINE | ID: mdl-24329330

RESUMO

We study a chain of anharmonic springs with tunable power law interactions as a minimal model to explore the propagation of strongly nonlinear solitary wave excitations in a background of thermal fluctuations. By treating the solitary waves as quasiparticles, we derive an effective Langevin equation and obtain their damping rate and thermal diffusion. These analytical findings compare favorably against numerical results from a Langevin dynamic simulation. In our chains composed of two-sided nonlinear springs, we report the existence of an expansion solitary wave (antisoliton) in addition to the compressive solitary waves observed for noncohesive macroscopic particles.

3.
Phys Rev Lett ; 111(4): 048001, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23931408

RESUMO

The interaction of a solitary wave with an interface formed by two strongly nonlinear noncohesive granular lattices displays rich behavior, characterized by the breakdown of continuum equations of motion in the vicinity of the interface. By treating the solitary wave as a quasiparticle with an effective mass, we construct an intuitive (energy- and linear-momentum-conserving) discrete model to predict the amplitudes of the transmitted solitary waves generated when an incident solitary-wave front, parallel to the interface, moves from a denser to a lighter granular hexagonal lattice. Our findings are corroborated with simulations. We then successfully extend this model to oblique interfaces, where we find that the angle of refraction and reflection of a solitary wave follows, below a critical value, an analogue of Snell's law in which the solitary-wave speed replaces the speed of sound, which is zero in the sonic vacuum.

4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(4 Pt 1): 040601, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22181079

RESUMO

We study the mechanical buckling of a freestanding superfluid layer. A topological defect in the phase of the quantum order parameter distorts the underlying metric into a surface of negative Gaussian curvature, irrespective of the sign of the defect charge. The resulting instability is in striking contrast with classical buckling, where the in-plane strain induced by positive (negative) disclinations is screened by positive (negative) curvature. We derive the conditions under which the quantum buckling instability occurs in terms of the dimensionless ratio between superfluid stiffness and bending modulus. An ansatz for the resulting shape of the buckled surface is analytically and numerically confirmed.

5.
Proteomics ; 4(7): 1903-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15221747

RESUMO

Sample preparation is crucial for extraction and higher resolution of proteins by two-dimensional gel electrophoresis (2-DE). In this study, we present an efficient protocol to extract proteins from mature rice leaves by minimizing the presence of nonprotein contaminants and by maximizing contact between the sample and extraction buffer. A combination of chemical and physical processes remarkably improved protein extraction for 2-DE. The efficiency of this protocol was demonstrated by comparison of the rice proteome at two developmental stages.


Assuntos
Eletroforese em Gel Bidimensional/métodos , Oryza/genética , Oryza/metabolismo , Proteômica/métodos , Bases de Dados como Assunto , Peptídeos/química , Folhas de Planta/metabolismo , Proteoma , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura , Fatores de Tempo
6.
Plant J ; 34(1): 1-11, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12662304

RESUMO

Sulfur amino acid composition is an important determinant of seed protein quality. A chimeric gene encoding sunflower seed albumin (SSA), one of the most sulfur-rich seed storage proteins identified so far, was introduced into rice (Oryza sativa) in order to modify cysteine and methionine content of the seed. Analysis of a transgenic line expressing SSA at approximately 7% of total seed protein revealed that the mature grain showed little change in the total sulfur amino acid content compared to the parental genotype. This result indicated that the transgenic rice grain was unable to respond to the added demand for cysteine and methionine imposed by the production of SSA. Analysis of the protein composition of the transgenic grain showed changes in the relative levels of the major seed storage proteins, as well as some non-storage proteins, compared to non-transgenic controls. Changes observed at the protein level were concomitant with differences in mRNA accumulation but not always with the level of transcription. The limited sulfur reserves appeared to be re-allocated from endogenous proteins to the new sulfur sink in the transgenic grain. We hypothesize that this response is mediated by a signal transduction pathway that normally modulates seed storage protein composition in response to environmental fluctuations in sulfur availability, via both transcriptional and post-transcriptional control of gene expression.


Assuntos
Albuminas/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Enxofre/metabolismo , Albuminas/genética , Sequência de Aminoácidos , Cisteína/metabolismo , Alimentos Geneticamente Modificados , Expressão Gênica , Engenharia Genética , Glutationa/metabolismo , Helianthus/genética , Metionina/metabolismo , Nitrogênio/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/genética , Sementes/metabolismo
7.
BMC Dev Biol ; 1: 11, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11439174

RESUMO

BACKGROUND: Mesenchymal-epithelial interactions play an important role in the physiology and pathology of epithelial tissues. Mesenchymal cells either associate with epithelium basement membrane [pericytes and perivascular monocyte-derived cells (MDC)] or reside within epithelium (MDC and T cells). Although intraepithelial mesenchymal cells were suggested to contribute to the epithelium physiology, their association with particular steps in differentiation of epithelial cells, interactions among themselves, and their fate remain unclear. We studied epitopes of mesenchymal cells and their products (immunoglobulins) in stratified epithelium of uterine ectocervix, which is one of the prototypes of complete cellular differentiation from stem into the aged cells. RESULTS: Perivascular CD14 primitive MDC associated with basal (stem) epithelial cells. Thy-1 pericytes of microvasculature secreted intercellular vesicles, which associated with Ki67 postmitotic epithelial cells expressing MHC class I. Intraepithelial T cells showed an association with veiled type MDC [dendritic cell (DC) precursors] among parabasal cells, and exhibited fragmentation after entering intermediate (mature) epithelial layers. Mature DC secreted CD68 and exhibited fragmentation after reaching mid intermediate layers. Binding of IgM was detected at the top of each layer: in the upper parabasal, upper intermediate, and most surface epithelial cells. IgG was confined to the entire superficial layer. CONCLUSIONS: These data suggest that the phylogenetically and ontogenetically developed hierarchy of mesenchymal cells (MDC, pericytes, T cells) and immunoglobulins (IgM, IgG) accompanies differentiation of epithelial cells from immature into the mature and aged phenotype. Further studies of an involvement of mesenchymal cells in the regulation of tissue homeostasis may bring novel approaches to the prevention and therapy of tissue dysfunctions characterized by permanent tissue immaturity (muscular dystrophy) or accelerated aging (degenerative diseases).


Assuntos
Células Epiteliais/fisiologia , Imunoglobulinas/fisiologia , Mesoderma/fisiologia , Apoptose/fisiologia , Complexo CD3/análise , Antígenos CD8/análise , Diferenciação Celular/fisiologia , Colo do Útero/irrigação sanguínea , Colo do Útero/citologia , Células Epiteliais/citologia , Epitélio/irrigação sanguínea , Epitélio/fisiologia , Feminino , Humanos , Imunoglobulinas/sangue , Imuno-Histoquímica , Mesoderma/citologia
8.
J Reprod Med ; 44(4): 363-6, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10319307

RESUMO

OBJECTIVE: To study the safe use of Dilapan at term for ripening the unfavorable cervix in an outpatient setting. STUDY DESIGN: Prospective review of cervical ripening with Dilapan in women at term gestation. Such women were assigned to either outpatient or inpatient cervical ripening with Dilapan. RESULTS: Twenty-one patients were assigned to each group. The length of induction was similar between women who had ambulatory cervical ripening and hospitalized patients (11 +/- 7 vs. 14 +/- 7 hours, respectively), and the rates of chorioamnionitis, endometritis and nonreassuring fetal heart rate tracings were also similar. However, the average length of hospitalization was significantly shorter for those who had ambulatory ripening as compared to those who were hospitalized (51 +/- 27 vs. 70 +/- 20 hours, respectively; P < .0007). CONCLUSION: The use of Dilapan for cervical ripening at term in an ambulatory setting is safe and effective and may decrease the overall hospitalization time and cost.


Assuntos
Assistência Ambulatorial/métodos , Maturidade Cervical/efeitos dos fármacos , Hospitalização , Trabalho de Parto Induzido/métodos , Polímeros/uso terapêutico , Adulto , Controle de Custos , Análise Custo-Benefício , Feminino , Custos Hospitalares , Humanos , Trabalho de Parto Induzido/economia , Tempo de Internação/economia , Tempo de Internação/estatística & dados numéricos , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Fatores de Tempo
9.
Arch Virol ; 143(9): 1815-22, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9787664

RESUMO

The complete nucleotide sequence of genome segment S4 of rice ragged stunt oryzavirus (RRSV, Thai-isolate) was determined. The 3823 bp sequence contains two large open reading frames (ORFs). ORF1, spanning nucleotides 12 to 3776, is capable of encoding a protein of M(r) 141,380 (P4a). The P4a amino acid sequence predicted from the nucleotide sequence contains sequence motifs conserved in RNA-dependent RNA polymerases (RDRPs). When compared for evolutionary relationships with RDRPs of other reoviruses using the amino acid sequences around the conserved GDD motif, P4a was shown to be more related to Nilaparvata lugens reovirus and reovirus serotype 3 than to rice dwarf phytoreovirus, bovine rotavirus or bluetongue virus. The ORF2, spanning nucleotides 491 to 1468, is out of frame with ORF1 and is capable of encoding a protein of 36,920 (P4b). Coupled in vitro transcription-translation from cloned ORF2 in wheat germ extract confirmed the existence of ORF2 but in vivo production and possible function of P4b is yet to be determined.


Assuntos
Genoma Viral , Oryza/virologia , RNA Polimerase Dependente de RNA/genética , Reoviridae/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , Fases de Leitura Aberta , RNA Polimerase Dependente de RNA/química , Proteínas Virais/química
10.
Arch Virol ; 142(8): 1719-26, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9672632

RESUMO

The nucleotide sequences of genome segments S7 and S10 of a Thai-isolate of rice ragged stunt virus (RRSV) were determined. The 1938 bp S7 sequence contains a single large open reading frame (ORF) spanning nucleotides 20 to 1843 that is predicted to encode a protein of M(r) 68,025. The 1,162 bp S10 sequence has a major ORF spanning nucleotides 142 to 1,032 that is predicted to encode a protein of M(r) 32,364. This S10 ORF is preceded by a small ORF (nt 20-55) which is probably a minicistron. Coupled in vitro transcription-translation from the two major ORFs gave protein products of the expected sizes. However, no protein was visualised from S10 when the small ORF sequence was included. Proteins were expressed in Escherichia coli from the full length ORF of S7 (P7) and from a segment of the S10 ORF (P10) fused to the ORF of glutathione S-transferase (GST). Neither fusion protein was recognised by polyclonal antibodies raised against RRSV particles. Furthermore, polyclonal antibodies raised against GST-P7 fusion protein did not recognise any virion structural polypeptides. These data strongly suggest that the proteins P7 and P10 do not form part of RRSV particle. This is further supported by observed sequence homology (though very weak) of predicted RRSV P7 and P10 with those of rice dwarf virus (RDV) non-structural proteins Pns6 and Pns9, respectively.


Assuntos
Oryza/virologia , Reoviridae/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Genoma Viral , Dados de Sequência Molecular
11.
J Gen Virol ; 77 ( Pt 12): 3155-60, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9000111

RESUMO

The complete nucleotide sequence of the genome segment 5 (S5) of a Thai isolate of rice ragged stunt virus (RRSV) was determined. The 2682 nucleotide sequence contains a single long open reading frame capable of encoding a polypeptide with a molecular mass of approximately 91 kDa. Polypeptides encoded by various truncated cDNAs of S5 were expressed using the pGEX fusion protein vector and the highest level of fusion protein was obtained from a construct encoding a hydrophilic region of S5 protein. Antibodies raised against this fusion protein recognized a minor polypeptide, with a molecular mass of approximately 91 kDa, that was present in purified preparations of RRSV particles, infected insect vectors and infected rice plants. This indicates that RRSV S5 encodes a minor structural protein. Comparing the RRSV S5 sequence with sequences of other reoviruses did not reveal any significant sequence similarities.


Assuntos
Vírus de Plantas/genética , RNA Viral , Reoviridae/genética , Proteínas Estruturais Virais/análise , Sequência de Aminoácidos , Animais , Sequência de Bases , Genoma Viral , Dados de Sequência Molecular , Oryza/virologia , Coelhos , Vírion
12.
Am J Reprod Immunol ; 36(6): 327-41, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8985508

RESUMO

PROBLEM: We have recently observed that the regression of corpora lutea (CL) in women during the reproductive period of life is accompanied by a diminution of Thy-1 differentiation protein release from vascular pericytes and an accumulation of T lymphocytes and activated macrophages among both degenerating granulosa lutein cells (GLC) and theca lutein cells. These data suggest that the immune system and other stromal factors, representing components of the "tissue control system," may play a role in regression of the CL. We investigated degenerating CL from climacteric women to address the possibility that the decline of immune functions with advancing age may result in incomplete regression of luteal tissue. This could contribute to the altered hormonal profiles and abnormal uterine bleeding that frequently occur during the climacteric. METHOD: Immunoperoxidase staining and image analysis were used to localize Thy-1 differentiation protein of vascular pericytes, cytokeratin staining of GLC, neural cell adhesion molecule expression by theca lutein cells, CD15 of neutrophils, CD4, CD14, CD68, and leukocyte common antigens of macrophages, and CD3 and CD8 determinants of T lymphocytes. We also investigated the expression of luteinizing hormone receptor (LH receptor) and mitogen activated protein kinases (MAP kinases) in luteal cells. Samples of regressing luteal tissue were obtained during the follicular phase from perimenopausal women (age 45-50) who exhibited prolonged or irregular cycles. For comparison, luteal tissues from women with regular cycles (age 29-45) and CL of pregnancy were also investigated. RESULTS: Corpora lutea of the climacteric women exhibited irregular regression of luteal tissue characterized by a lack of cytoplasmic vacuolization and nuclear pyknosis in GLC, and by a persistence of theca lutein cells exhibiting hyperplasia and adjacent theca externa layers. This was accompanied by a continuing release of Thy-1 differentiation protein from vascular pericytes. Persisting GLC lacked surface expression of macrophage markers (CD4, CD14, CD68 and leukocyte common antigen) as well as nuclear granules exhibiting CD15 of neutrophils, detected in regularly regressing GLC. In addition, such persisting GLC showed weak or no LH receptor expression, and retained the expression of cytokeratin. They also exhibited enhanced staining for MAP kinases. Strong cytoplasmic MAP kinase expression with occasional nuclear translocation was also detected in persisting theca lutein cells, indicating high metabolic activity of these cells. T lymphocytes, although occasionally present in luteal stroma within luteal convolutions, did not invade among persisting GLC and were virtually absent from layers of theca externa and theca lutein cells. CONCLUSIONS: These data indicate that the regressing CL in climacteric women may exhibit persistence of luteal cells, perhaps because of age-induced alterations of the immune system and other local stromal homeostatic mechanisms involved in the elimination of luteal cells. Persisting GLC and/or theca lutein cells may exhibit abnormal hormonal secretion that contributes to the alteration of target tissues, such as the endometrium, resulting in abnormal uterine bleeding, hyperplasia, and neoplasia.


Assuntos
Envelhecimento/imunologia , Climatério/imunologia , Luteólise/imunologia , Especificidade de Órgãos/imunologia , Adulto , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Endométrio/imunologia , Feminino , Humanos , Imuno-Histoquímica , Queratinas/análise , Antígenos CD15/análise , Pessoa de Meia-Idade , Moléculas de Adesão de Célula Nervosa/análise , Ovário/imunologia , Antígenos Thy-1/análise
13.
Arch Virol ; 141(9): 1689-701, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8893791

RESUMO

The nucleotide sequence of DNA complementary to rice ragged stunt oryzavirus (RRSV) genome segment 8 (S8) of an isolate from Thailand was determined. RRSVS8 is 1914 bp in size and contains a single large open reading frame (ORF) spanning nucleotides 23 to 1810 which is capable of encoding a protein of M(r) 67,348. The N-terminal amino acid sequence of a approximately 43K virion polypeptide matched to that inferred for an internal region of the S8 coding sequence. These data suggest that the 43K protein is encoded by S8 and is derived by a proteolytic cleavage. Predicted polypeptide sizes from this possible cleavage of S8 protein are 26K and 42K. Polyclonal antibodies raised against a maltose binding protein (MBP)-S8 fusion polypeptide (expressed in Escherichia coli) recognised four RRSV particle associated polypeptides of M(r) 67K, 46K, 43K and 26K and all except the 26K polypeptide were also highly immunoreactive to polyclonal antibodies raised against purified RRSV particles. Cleavage of the MBP-S8 fusion polypeptide with protease Factor X produced the expected 40K MBP and two polypeptides of apparent M(r) 46K and 26K. Antibodies to purified RRSV particles reacted strongly with the intact fusion protein and the 46K cleavage product but weakly to the 26K product. Furthermore, in vitro transcription and translation of the S8 coding region revealed a post-translational self cleavage of the 67K polypeptide to 46K and 26K products. These data indicate that S8 encodes a structural polypeptide, the majority of which is auto-catalytically cleaved to 26K and 46K proteins. The data also suggest that the 26K protein is the self cleaving protease and that the 46K product is further processed or undergoes stable conformational changes to a approximately 43K major capsid protein.


Assuntos
Capsídeo/biossíntese , Oryza/virologia , Processamento de Proteína Pós-Traducional , Reoviridae/genética , Reoviridae/metabolismo , Sequência de Aminoácidos , Anticorpos , Sequência de Bases , Capsídeo/química , Capsídeo/genética , Clonagem Molecular , Primers do DNA , Escherichia coli , Genoma Viral , Dados de Sequência Molecular , Peso Molecular , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Tailândia , Vírion/genética , Vírion/metabolismo
14.
Biol Reprod ; 53(6): 1373-84, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8562694

RESUMO

Factors determining the life span of the human corpus luteum (CL) are not known. In addition to being determined by hormonal factors, such as hCG, the life of luteal cells may be determined by the preservation of luteal vascularization. Furthermore, the CL represents an immunologically unique tissue, as it is formed after menarche, long after adaptation of the immune system toward self. Thus, CL regression may be immunologically mediated. To determine what role the vasculature and immune system play in human CL development and regression, we examined immunohistochemically 1) the expression of Thy-1 differentiation protein by vascular pericytes, 2) the expression of major histocompatibility complex (MHC) class I and class II molecules in granulosa lutein cells (GLC), and 3) infiltration of the CL by macrophages and T lymphocytes. LH receptor (LHR) and cytokeratin 18 expression were also studied. In developing CL, the pericytes of luteal microvasculature released Thy-1 differentiation protein among the endothelial cells of proliferating vessels. In mature CL, Thy-1 released from vascular pericytes accumulated on the surface of GLC, and these cells exhibited LHR immunoreactivity (LHRI). Overall LHRI increased during the luteal phase and was strongest at the beginning of the late luteal phase. Although vascular pericytes showed strong LHRI, no staining of endothelium was detected during the luteal phase. GLC exhibited strong cytokeratin staining and moderate staining for MHC class I and MHC class II antigens; numerous macrophages were detected in luteal tissue. During pregnancy, the staining pattern was similar to that seen in the mature CL at the end of the midluteal phase. During the late luteal phase, surface expression of MHC class I and MHC class II antigens by GLC was substantially enhanced, and some T cells invaded among luteal cells. By the end of the cycle, an acute regression of vasculature and luteal tissue was observed along the fibrous septa. The remaining GLC showed only surface and no cytoplasmic LHRI. During the subsequent cycle, in the presence of numerous T cells, regressing GLC exhibited strong surface expression of various macrophage markers, such as CD4, CD14, CD68, and leukocyte common antigen, a feature not detected in the CL during the luteal phase nor described in other tissues. A complete loss of cytokeratin staining in GLC was observed. In regressing CL, strong LHRI was present in the endothelium of small and large luteal vessels. In conclusion, vascular pericytes and macrophages may stimulate the development and senescence of luteal tissue. The senescence of GLC may be inconsistent with preservation of luteal vasculature, and T lymphocytes appear to participate in terminal regression of the CL. Regression of luteal tissue therefore resembles immunologic rejection of a transplant. During pregnancy, the aging process of GLC appears to be interrupted, possibly due to the temporary acceptance of the CL "graft."


Assuntos
Imunidade , Luteólise/imunologia , Receptores do LH/análise , Adulto , Corpo Lúteo/irrigação sanguínea , Corpo Lúteo/química , Corpo Lúteo/imunologia , Endotélio Vascular/química , Feminino , Células da Granulosa/química , Células da Granulosa/imunologia , Antígenos de Histocompatibilidade Classe I/análise , Antígenos de Histocompatibilidade Classe II/análise , Humanos , Técnicas Imunoenzimáticas , Queratinas/análise , Macrófagos/imunologia , Pessoa de Meia-Idade , Gravidez , Linfócitos T/imunologia , Antígenos Thy-1/análise
15.
Am J Obstet Gynecol ; 173(6): 1820-5, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8610769

RESUMO

OBJECTIVE: Our purpose was to determine the effects of platelet-derived growth factor on the proliferation of endometrial epithelial cells. Platelet-derived growth factor and its receptors have been identified in the endometrium, and platelet-derived growth factor is a mitogen for endometrial stromal cells. Released from macrophages and platelets at sites of ectopic endometrial growth, platelet-derived growth factor could promote the progression of endometriosis and endometrial cancer. STUDY DESIGN: Endometrial epithelial cell lines were developed from proliferative-phase endometria from two patients without endometrial lesions. Cell lines were confirmed to be epithelial. Proliferation assays were conducted on both lines with recombinant human platelet-derived growth factor-AA, AB, and BB. Assays were also performed at different doses, times, and cell densities with platelet-derived growth factor. RESULTS: All isoforms of platelet-derived growth factor were potent mitogens for both endometrial epithelial cell lines. The greatest proliferative responses were achieved at 10 ng/ml and at 24 hours. Responses decreased significantly in confluent cultures. CONCLUSIONS: These results suggest that endometrial epithelial cells have functional platelet-derived growth factor-alpha receptors that signal cell replication. The greater activity of platelet-derived growth factor in subconfluent cultures may indicate that receptor numbers or affinity are up-regulated when cell-cell contact is disrupted. These data support a role for platelet-derived growth factor in normal endometrial proliferation and in pathologic proliferation such as endometriosis and endometrial cancer.


Assuntos
Endométrio/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Adulto , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Endométrio/citologia , Células Epiteliais , Epitélio/efeitos dos fármacos , Feminino , Humanos , Fatores de Tempo
16.
Am J Reprod Immunol ; 33(4): 323-40, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7546251

RESUMO

PROBLEM: Formation of primordial follicles in adult ovaries could be a cryptic process limited to relatively small areas of the ovarian cortex and occurring during a certain stage of the menstrual cycle. Such an event may require a specific milieu provided by factors involved in developmental processes, i.e., morphoregulatory molecules and macrophages. METHOD: Adult human ovaries were investigated by immunohistochemistry for surface epithelium and granulosa cell markers (cytokeratin 18 and MHC class I), immune system-related morphoregulatory molecules (Thy-1 glycoprotein and N-CAM), and macrophage phenotypes (CD14, CD68, and MHC class II). RESULTS: In some ovaries 300-500 microns areas of surface epithelium were overgrown by tunica albuginea, descended into the stroma, and apparently fragmented into individual small (20-40 microns) follicle-like cell nests. Differentiation of the surface epithelium was accompanied by macrophages and Thy-1 glycoprotein. Small segments of surface epithelium showed N-CAM and a lacked MHC class I expression. In such segments, clear spherical germ-like cells migrated into the deeper stroma, associated with the microvasculature, and eventually aggregated with follicle-like cell nests. CONCLUSIONS: Our data suggest that surface epithelium may be involved in the formation of some primordial follicles in adult ovaries. This process, and further follicular fate, may require a precise interplay of immune system related morphoregulatory molecules and macrophages.


Assuntos
Folículo Ovariano/fisiologia , Ovário/fisiologia , Adulto , Diferenciação Celular/fisiologia , Epitélio/química , Epitélio/fisiologia , Feminino , Atresia Folicular/metabolismo , Antígenos de Histocompatibilidade Classe I/análise , Humanos , Imuno-Histoquímica , Queratinas/análise , Pessoa de Meia-Idade , Folículo Ovariano/química , Ovário/química , Ovário/citologia , Pós-Menopausa/fisiologia , Pré-Menopausa/fisiologia , Células Estromais/química , Células Estromais/fisiologia , Células Tecais/química , Células Tecais/fisiologia
17.
J Assist Reprod Genet ; 12(2): 123-31, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7670270

RESUMO

PURPOSE: Recent studies have shown that proliferation and differentiation of various cell types is regulated by cell-cycle-related proteins, such as protein p53 and retinoblastoma protein pRb. METHODS: Three monoclonal antibodies to p53 (PAb240, PAb421, and PAb1801) and 3H9 monoclonal antibody to pRb were utilized for localization of proteins by peroxidase immunohistochemistry in frozen tissue sections. RESULTS: Nuclear and nucleolar p53 expression was detected in nondividing and relatively stable cells, e.g., oocytes in primordial follicles and granulosa lutein cells. On the other hand, strong cytoplasmic p53 expression was detected in proliferating and low differentiated epithelial cells of the ovarian surface epithelium, amnion, endocervix and ectocervix, indicating enhanced p53 synthesis. Not all three p53 antibodies reacted with each tissue, perhaps due to structural and conformational changes in the p53 molecule, accompanying p53 association with other proteins, e.g., tissue specific transcription factor interactions. pRb expression was usually restricted to the cell nuclei and nucleoli. However, glandular cells of the female reproductive tract showed cytoplasmic pRb expression in juxtaluminal (secretory) segments of cells, a feature not previously described in any cell type. p53 and pRb immunoreactivities declined with advanced differentiation of cells. No p53 or pRb was detected in placental syncytiotrophoblast or terminally differentiated squamous epithelial cells. CONCLUSION: Our data indicate that large quantities of p53 are synthesized in cells leaving the cell cycle and entering differentiation. Except in glandular cells, the pRb expression is confined to the cell nuclei and nucleoli. A unique cytoplasmic expression of pRb in juxtaluminal segments of glandular cells suggests a role for pRb in human female fertility and conception.


Assuntos
Tubas Uterinas/metabolismo , Ovário/metabolismo , Proteína do Retinoblastoma/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Útero/metabolismo , Anticorpos Monoclonais/imunologia , Diferenciação Celular , Divisão Celular , Nucléolo Celular/metabolismo , Colo do Útero/citologia , Colo do Útero/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endométrio/citologia , Endométrio/metabolismo , Membranas Extraembrionárias/metabolismo , Tubas Uterinas/citologia , Feminino , Humanos , Imuno-Histoquímica , Oócitos/metabolismo , Ovário/citologia , Placenta/citologia , Placenta/metabolismo , Proteína do Retinoblastoma/análise , Proteína Supressora de Tumor p53/análise , Útero/citologia
18.
Arch Virol ; 140(11): 1945-56, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7503693

RESUMO

Nucleotide sequences of rice ragged stunt virus (RRSV) genome segment 9 (S9) from a Thai and an Indian isolate were determined. Both sequences are 1132 bp long, contain a single large open reading frame (ORF) spanning nucleotide residues 14 to 1027 and are capable of encoding a protein of 38.5K. The two isolates are 94.6% and 99.4% identical at the nucleotide and amino acid level, respectively. The authenticity of these coding sequences was confirmed by identifying a approximately 38K protein in the RRSV particle with an N-terminal amino acid sequence identical to that inferred from the S9 ORF. Furthermore, cDNA of S9 from each isolate incorporated into the bacterial expression vector pGEX3-X produced a fusion protein that reacted with antibodies raised against purified RRSV particles. Cleaving these fusion proteins with protease factor X liberated a approximately 38K polypeptide.


Assuntos
Antígenos Virais/genética , Oryza/microbiologia , Reoviridae/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA/química , DNA Complementar/genética , Genes Virais , Índia , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Viral/genética , Tailândia , Proteínas Virais/imunologia , Proteínas Estruturais Virais/genética , Vírion/imunologia
20.
Indian J Ophthalmol ; 40(3): 96-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1302236

RESUMO

A 42 year old man presented with acute bilateral uveitis and necrotizing retinitis. Systemic investigations including test for AIDS and CMV retinitis were negative. Despite oral Acyclovir, both eyes progressed rapidly to retinal detachment with loss of vision. Early recognition is necessary to diagnose the bilateral acute retinal necrosis syndrome and initiate treatment. Bilateral acute retinal necrosis (BARN) is a term first coined by Young and Bird in 1978 although the syndrome had been originally described by Urayama et al as an unilateral condition. This syndrome is characterized by the triad of acute confluent peripheral necrotizing retinitis, moderate to severe vasculitis and vitritis in an otherwise healthy individual. Rhegmatogenous retinal detachment occurs within two to three months of the onset of the disease and the second eye is involved in 36% of patients, usually within 6 weeks. We herein report a patient who presented with simultaneous BARN leading to retinal detachment in a matter of days. Also, to our knowledge this is the first report of this condition in India.


Assuntos
Síndrome de Necrose Retiniana Aguda/diagnóstico , Adulto , Angiofluoresceinografia , Fundo de Olho , Humanos , Masculino , Descolamento Retiniano/diagnóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA