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1.
J Assist Reprod Genet ; 32(11): 1679-84, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26347343

RESUMO

PURPOSE: Total fertilisation failure (TFF), even with intracytoplasmic sperm injection (ICSI), occurs in approximately 3 % of cycles, can be recurrent and the exact cause is difficult to elucidate. Differentiation between oocyte and sperm-related cause of TFF is possible using mouse oocyte-activation techniques, but is not an option within most clinical settings. Therefore, the management of these couples is clinically driven, and the endpoint, if recurrent, is often the use of donor gametes. However, with the invariable lack of a definitive cause of TFF, any decision between the use of donor sperm or oocytes remains an emotive one. We present two case reports demonstrating the importance of appropriate investigation, activation techniques (mechanical and chemical) and clinical management options to develop a clinical algorithm prior to the use of donor gametes. METHODS: This study is composed of two case reports of assisted reproduction investigation and treatment within an assisted conception unit for couples with recurrent total fertilisation failure. RESULTS: Using appropriate investigation (endocrine, urological and embryological) and treatments (ICSI, IMSI, oocyte-activation techniques), a fertilisation rate of 48 % was achieved in two cycles in couples following a total of nine previous cycles (and 200 previously collected eggs) with TFF. CONCLUSIONS: Oocyte activation requires the triggering of intracellular calcium oscillations by the release of a sperm-specific factor (phospholipase C zeta (PLCζ)) into the oocyte cytoplasm. Although, PLCζ deficiencies have been demonstrated as putative causes of failed activation, impaired oocyte responsiveness may also be a factor. The use of donor gametes is often recommended and is often the required endpoint of treatment. However, these reports outline a clinical algorithm that potentially offers success without donation, and also offers a systematic approach to help decide whether donor oocytes or sperm should be recommended.


Assuntos
Fertilização in vitro/métodos , Técnicas de Maturação in Vitro de Oócitos/métodos , Fosfolipases Tipo C/metabolismo , Adulto , Algoritmos , Ionóforos de Cálcio/farmacologia , Feminino , Humanos , Masculino , Doação de Oócitos , Oócitos/efeitos dos fármacos , Gravidez , Injeções de Esperma Intracitoplásmicas/métodos , Falha de Tratamento , Fosfolipases Tipo C/análise
2.
Anaesthesia ; 68(11): 1114-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24006919

RESUMO

In 2008, the UK National Patient Safety Agency (NPSA) made recommendations for safe arterial line management. Following a patient safety incident in our intensive care unit (ICU), we surveyed current practice in arterial line management and determined whether these recommendations had been adopted. We contacted all 241 adult ICUs in the UK; 228 (94.6%) completed the survey. Some NPSA recommendations have been widely implemented - use of sodium chloride 0.9% as flush fluid, two-person checking of fluids before use - and their practice was consistent. Others have been incompletely implemented and many areas of practice (prescription of fluids, two-person checking at shift changes, use of opaque pressure bags, arterial sampling technique) were highly variable. More importantly, the use of the wrong fluid as an arterial flush was reported by 30% of respondents for ICU practice, and a further 30% for practice elsewhere in the hospital. Our survey provides evidence of continuing risk to patients.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Coleta de Amostras Sanguíneas/normas , Cuidados Críticos/normas , Pesquisas sobre Atenção à Saúde/métodos , Segurança do Paciente/estatística & dados numéricos , Dispositivos de Acesso Vascular/normas , Adulto , Coleta de Amostras Sanguíneas/estatística & dados numéricos , Cuidados Críticos/métodos , Cuidados Críticos/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Humanos , Unidades de Terapia Intensiva/normas , Unidades de Terapia Intensiva/estatística & dados numéricos , Erros Médicos/estatística & dados numéricos , Segurança do Paciente/normas , Guias de Prática Clínica como Assunto , Reino Unido , Dispositivos de Acesso Vascular/estatística & dados numéricos
3.
J Assist Reprod Genet ; 27(9-10): 555-60, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20676752

RESUMO

BACKGROUND: The development and refinement of blastocyst media in recent years has allowed embryos to be cultured in-vitro for 5 or 6 days post oocyte retrieval and has been established as an effective selection tool to aid embryo selection for IVF treatment. It is generally accepted that blastocyst culture is not an appropriate option for all patients but the criteria for patient selection varies between clinics. Our blastocyst culture programme started in February 2005; the patient criteria was set at a minimum of 4 oocytes retrieved, a minimum of 4 2PN pronuclear embryos and at least 4 8-cell embryos of any quality on Day 3 where the female patient was 34 years and under. In the female age group of 35 years and over the criteria was at least 6 oocytes retrieved, a minimum of 6 2PN pronuclear embryos and at least 6 8-cell embryos of any quality on day 3. Improvements in pregnancy rates demonstrated the effectiveness of blastocyst transfer and clinical opinion was that the criteria should be adjusted to allow this option to be available to an increased patient population. From February 2007 the blastocyst patient selection criteria was changed to at least 4 oocytes retrieved, at least 4 2PN pronuclear embryos and at least 2 8-cell and 2 6-cell or 7-cell embryos of top quality on Day 3 in women 38 years and under. For women 39 years and over the criteria was lowered to at least 5 eggs retrieved, at least 5 2PN and at least 3 8-cell embryos and 2 6-cell embryos of top quality on Day 3. METHODS: Retrospective statistical analysis was carried out to determine the pregnancy rates, live birth rates and twin rate for the period under the initial criteria and to examine the impact that lowering the criteria for patient selection for blastocyst culture had on these parameters. RESULTS: There was an overall fall in the ongoing pregnancy/live birth rate from 50.9% under the old criteria to 45.0% under the new criteria. However, the patients who had blastocyst culture under the new criteria but would have had day-3 embryo transfer under the initial criteria had a significantly increased live birth/ongoing pregnancy rate from 22.7% to 40.7%. There is an increase in the number of blastocyst culture cycles from 26.4% under the old criteria to 39.1% with the refined criteria. The twin pregnancy rate was reduced from 25.2% to 17.5%. CONCLUSION: The result of this cohort study revealed that lowering the blastocyst selection criteria may lead to a lower overall clinical live birth rate from blastocyst culture; however, it will benefit a specific group of patients to achieve a better pregnancy and live birth rate. Furthermore, it increases the number of patients who will benefit from the blastocyst culture programme and also reduces multiple pregnancy rate.


Assuntos
Técnicas de Cultura Embrionária , Seleção de Pacientes , Técnicas de Reprodução Assistida , Fatores Etários , Blastocisto , Distribuição de Qui-Quadrado , Fase de Clivagem do Zigoto , Feminino , Humanos , Gravidez , Resultado da Gravidez , Taxa de Gravidez
4.
Oncogene ; 26(55): 7709-14, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-17603562

RESUMO

The mechanisms of signal transduction from cell surface receptors to the interior of the cell are fundamental to the understanding of the role that positive and negative growth factors play in cell physiology and in human diseases. Here, we show that a functional link between phosphatidylinositol-3-OH kinase (PI3K) and Ras is suppressed by the beta-galactoside binding protein (betaGBP) molecule, a cytokine and a negative cell-cycle regulator. Ras-mitogen-activated protein kinase (MAPK) signalling is blocked by betaGBP owing to its ability to inhibit the p110 catalytic subunit of PI3K, whose basal activity is required for Ras activation. Functional inhibition of p110 by betaGBP results in downregulation of PI3K activity, suppression of Ras-GTP loading, consequent loss of MAPK activation and block of cell proliferation. This study sheds light on the molecular mechanisms whereby betaGBP can control cell proliferation and, by extension, may potentially control tumorigenesis by controlling PI3K.


Assuntos
Transformação Celular Neoplásica/metabolismo , Galectina 1/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas ras/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Galectina 1/genética , Galectina 1/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos
5.
J Arthroplasty ; 17(3): 267-73, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11938500

RESUMO

This study reports on the incidence of primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) for primary osteoarthritis in Australia. Age-specific and gender-specific numbers for Australia, 1994 through 1998, and South Australia, 1988 through 1998, were obtained. Incidences were calculated per 100,000 population. In Australia, primary THA increased from 50.9/10(5) (1994) to 60.9/10(5) (1998). TKA increased from 56.4/10(5) to 76.8/10(5). Stratified by age and gender, changes in incidence for South Australia with respect to time were tested using regression analysis. South Australia showed a significant increase in the overall incidence of THA (P=.012) and TKA (P<.001), although this was not uniform across all age groups. No significant gender differences were found. The incidence of THA is increasing, and the incidence of TKA is increasing at a greater rate.


Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Artroplastia do Joelho/estatística & dados numéricos , Osteoartrite do Quadril/cirurgia , Osteoartrite do Joelho/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Distribuição de Poisson , Análise de Regressão
6.
Nucleic Acids Res ; 29(13): 2715-24, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11433016

RESUMO

Properties of poliovirus RNA-dependent RNA polymerase (3D(pol)) including optimal conditions for primer extension, processivity and the rate of dissociation from primer-template (k(off)) were examined in the presence and absence of viral protein 3AB. Primer-dependent polymerization was examined on templates of 407 or 1499 nt primed such that fully extended products would be 296 or 1388 nt, respectively. Maximal primer extension was achieved with low rNTP concentrations (50-100 microM) using pH 7 and low (<1 mM) MgCl(2) and KCl (<20 mM) concentrations. However, high activity (about half maximal) was also observed with 500 microM rNTPs providing that higher MgCl(2) levels (3-5 mM) were used. The enhancement observed with the former conditions appeared to result from a large increase in the initial level or active enzyme that associated with the primer. 3AB increased the number of extended primers at all conditions with no apparent change in processivity. The k(off) values for the polymerase bound to primer-template were 0.011 +/- 0.005 and 0.037 +/- 0.006 min(-1) (average of four or more experiments +/- SD) in the presence or absence of 3AB, respectively. The decrease in the presence of 3AB suggested an enhancement of polymerase binding or stability. However, binding was tight even without 3AB, consistent with the highly processive (at least several hundred nucleotides) nature of 3D(pol). The results support a mechanism whereby 3AB enhances the ability of 3D(pol) to form a productive complex with the primer-template. Once formed, this complex is very stable resulting in highly processive synthesis.


Assuntos
Poliovirus/enzimologia , Poliovirus/genética , RNA Viral/biossíntese , RNA Polimerase Dependente de RNA/metabolismo , RNA/genética , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Cloreto de Magnésio/farmacologia , Ligação Proteica/efeitos dos fármacos , RNA Viral/genética , RNA Viral/metabolismo , Moldes Genéticos , Termodinâmica , Proteínas do Core Viral/metabolismo
7.
Virus Res ; 74(1-2): 119-32, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11226580

RESUMO

The fidelity of poliovirus RNA-dependent RNA polymerase (3D(pol)) was determined using a system based on the fidelity of synthesis of the alpha-lac gene which codes for a subunit of beta-galactosidase. Synthesis products are screened for mutations by an alpha-complementation assay, in which the protein product from alpha-lac is used in trans to complement beta-galactosidase activity in bacteria that do not express alpha-Lac. Several polymerases have been analyzed by this approach allowing comparisons to be drawn. The assay included RNA synthesis by 3D(pol) on an RNA template that coded for the N-terminal region of alpha-Lac. The product of this reaction was used as a template for a second round of 3D(pol) synthesis and the resulting RNA was reverse transcribed to DNA by MMLV-RT. The DNA was amplified by PCR and inserted into a vector used to transform Escherichia coli. The bacteria were screened for beta-galactosidase activity by blue-white phenotype analysis with white or faint blue colonies scored as errors made during synthesis on alpha-lac. Results showed a mutation rate for 3D(pol) corresponding to approximately 4.5x10(-4) errors per base (one error in approximately 2200 bases). Analysis of mutations showed that base substitutions occurred with greater frequency than deletions and insertions.


Assuntos
Mutação , Poliovirus/enzimologia , RNA Polimerase Dependente de RNA/genética , Sequência de Bases , Análise Mutacional de DNA , DNA Recombinante , Escherichia coli , Vetores Genéticos , Dados de Sequência Molecular , Poliovirus/genética , RNA Polimerase Dependente de RNA/metabolismo , Especificidade por Substrato , Moldes Genéticos , beta-Galactosidase/genética
9.
J Clin Microbiol ; 38(6): 2227-31, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10834981

RESUMO

Seven serological tests, two immunochromatographic tests, ICT Tuberculosis and RAPID TEST TB, and five enzyme-linked immunosorbent assays, TUBERCULOSIS IgA EIA, PATHOZYME-TB complex, PATHOZYME-MYCO IgG, PATHOZYME-MYCO IgA, and PATHOZYME-MYCO IgM, were evaluated simultaneously with 298 serum samples from three groups of individuals: 44 patients with active tuberculosis, 204 controls who had undergone the Mantoux test (89 Mantoux test-positive and 115 Mantoux test-negative controls), and 50 anonymous controls. The sensitivities of the tests with sera from patients with active tuberculosis were poor to modest, ranging from 16 to 57%. All the tests performed equally with sera from subgroups of those with active tuberculosis, those with pulmonary (33 patients) versus extrapulmonary (11 patients) disease, and those who were smear positive (24 patients) versus smear negative (12 patients) (P > 0.05). The specificities of the tests ranged from 80 to 97% with sera from the Mantoux test controls and 62 to 100% with sera from the anonymous controls. The TUBERCULOSIS IgA EIA had the highest sensitivity (57%) with sera from patients with active tuberculosis, with a high specificity of 93% with sera from the Mantoux test controls, but a very poor specificity of 62% with sera from the anonymous controls. Overall, ICT Tuberculosis followed by PATHOZYME-MYCO IgG had the best performance characteristics, with sensitivities of 41 and 55%, respectively, with sera from patients with active tuberculosis and specificities of 96 and 89%, respectively, with sera from the Mantoux test controls and 88 and 90%, respectively, with sera from the anonymous controls. By combining all the test results, a maximum sensitivity of 84% was obtained, with reciprocal drops in specificities to 55 and 42% for the Mantoux test controls and anonymous controls, respectively. The best combination was that of ICT Tuberculosis and PATHOZYME-MYCO IgG, with a sensitivity of 66% and a specificity of 86% for the Mantoux test controls and a sensitivity and specificity of 78% for the anonymous controls. While a negative result by any one of these tests would be useful in helping to exclude disease in a population with a low prevalence of tuberculosis, a positive result may aid in clinical decision making when applied to symptomatic patients being evaluated for active tuberculosis.


Assuntos
Testes Sorológicos/métodos , Tuberculose Pulmonar/diagnóstico , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia de Afinidade , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Eur J Cancer ; 35(6): 978-83, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10533482

RESUMO

Conflict between mitogenic pressure, as is the case in tumour cells and an imposed inability to proceed through the cell cycle may result in cell death. In the present study we examined the effect of beta galactoside binding protein (beta GBP), a negative growth factor which controls cell cycle transition from S phase into G2, on three human mammary cell lines which differ for oncogenic potential, oestrogen receptor expression and expression of the EGF receptor family. We found that in all cases beta GBP induced a cell cycle block prior to the cells' entry into G2 and that this was followed by progressive apoptotic death. This evidence on epithelial cancer cells parallels previous data on tumour cells of mesenchymal origin and suggests that beta GBP has potential therapeutic implications in the treatment of cancers.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Hemaglutininas/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Feminino , Galectinas , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Recombinantes/uso terapêutico , Células Tumorais Cultivadas
11.
J Clin Microbiol ; 37(10): 3229-32, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10488182

RESUMO

We evaluated an in vitro test of cell-mediated immunity, the tuberculin gamma interferon assay, QuantiFERON-TB (QIFN), in 455 individuals from three groups: group I, 237 immigrants from high-risk countries; group II, 127 health care workers undergoing Mantoux testing; group III, 91 patients being investigated for possible active tuberculosis (79 patients) or Mycobacterium avium-Mycobacterium intracellulare complex infection (12 patients). The QIFN results were compared either to those of the Mantoux test or to microbiological and clinical diagnosis, as appropriate. In each group the correlation between the diameter of induration for the skin test and the magnitude of QIFN response was significant and of moderate strength (Spearman's rank correlation coefficient; rho = 0.59 to 0.61; P < 0.001). For group I, the agreement between QIFN and Mantoux results was 89% for Mantoux-negative and 64% for Mantoux-positive individuals. For group II, when >/=10-mm-diameter induration was taken as positive, the agreement was 81% for Mantoux-negative and 67% for Mantoux-positive individuals. For group III, agreement was 81% for Mantoux-negative and 86% for Mantoux-positive patients. For patients being evaluated for active tuberculosis, the performance of the Mantoux test was not statistically different from that of the QIFN assay. In patients with active tuberculosis, the assay had a sensitivity of 77%, not significantly higher for extrapulmonary than pulmonary cases (83% versus 74%). QIFN sensitivity was not significantly different for smear-negative or smear-positive cases (80% versus 71%). The QIFN assay is a potential replacement for the Mantoux test. The acceptability of these performance values and those of similar evaluations will determine the place this test will have in detecting evidence of mycobacterial infection.


Assuntos
Interferon gama/biossíntese , Teste Tuberculínico , Tuberculina , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Vacina BCG/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Vacinação
12.
Int J Psychiatry Med ; 29(1): 97-105, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10376236

RESUMO

OBJECTIVE: To examine the efficacy of clonazepam in chest pain patients with panic disorder and normal coronary arteries. METHOD: We conducted a placebo controlled, double blind, flexible dose (1-4 mg/d), six-week trial of clonazepam. All subjects (N = 27) had current panic disorder and a negative coronary angiogram or thallium exercise tolerance test within the previous year. RESULTS: Analyses show modest improvements in the clonazepam and placebo groups over the first four weeks in both primary outcome measures. Eight of twelve (67%) clonazepam treated patients responded with reduction of panic attacks by week four to zero per week or half of initial frequency, while seven of fifteen (47%) placebo treated patients responded (not significant). When response was measured by 50 percent reduction in Hamilton Anxiety total score, however, seven of twelve (58%) clonazepam treated patients responded, while two of fifteen (14%) placebo treated patients responded, (p = .038) by Fisher's exact test. Within-subject improvements over the first four weeks were not significantly greater for the clonazepam group than for the placebo group on either outcome measure. CONCLUSIONS: These results show a generally good outcome in chest pain patients with panic disorder, and they provide suggestive evidence for the efficacy of clonazepam compared to placebo. This study points to the need for larger, well-funded treatment studies of chest pain patients with panic disorder.


Assuntos
Clonazepam/uso terapêutico , Moduladores GABAérgicos/uso terapêutico , Transtorno de Pânico/tratamento farmacológico , Transtorno de Pânico/etiologia , Dor no Peito , Vasos Coronários , Método Duplo-Cego , Seguimentos , Humanos , Recidiva
13.
Psychosom Med ; 61(1): 6-17, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10024062

RESUMO

OBJECTIVE: The literature on the mortality of depression was assessed with respect to five issues: 1) strength of evidence for increased mortality, 2) controlling for mediating factors, 3) the contribution of suicide, 4) variation across sample types, and 5) possible mechanisms. METHOD: All relevant English language databases from 1966 to 1996 were searched for reviews and studies that included 1) a formal assessment of depressive symptoms or disorders, 2) death rates or risks, and 3) an appropriate comparison group. RESULTS: There were 57 studies found; 29 (51%) were positive, 13 (23%) negative, and 15 (26%) mixed. Twenty-one studies (37%) ranked among the better studies on the strength of evidence scale used in this study, but there are too few comparable, well-controlled studies to provide a sound estimate of the mortality risk associated with depression. Only six studies controlled for more than one of the four major mediating factors. Suicide accounted for less than 20% of the deaths in psychiatric samples, and less than 1% in medical and community samples. Depression seems to increase the risk of death by cardiovascular disease, especially in men, but depression does not seem to increase the risk of death by cancer. Variability in methods prevents a more rigorous meta-analysis of risk. CONCLUSION: The studies linking depression to early death are poorly controlled, but they suggest that depression substantially increases the risk of death, especially death by unnatural causes and cardiovascular disease. Future well-controlled studies of high risk groups may guide efforts to develop treatments that reduce the mortality risk of depression.


Assuntos
Transtorno Depressivo/mortalidade , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
J Cell Physiol ; 178(1): 102-8, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9886496

RESUMO

The cell cycle is negatively regulated by diverse molecular events which originate in part from the interaction of secreted proteins with specific cell surface receptors. By exerting negative control on cell proliferation, these factors can help maintain cell number balance both through growth restraints and the induction of apoptosis and may thus contribute to prevent or control tumourigenesis. Here we report that betaGBP, a negative growth factor which controls transition from S phase into G2, causes an S/G2 growth arrest in both normal and leukaemic T cells. However, in leukaemic T cells but not in normal T lymphocytes, growth arrest is followed by apoptosis. Analysis of possible mechanisms of induction of apoptosis does not support Fas and Fas L as having a main role but points instead to Bcl-2 and Bax. The induction of apoptosis in leukaemic T cells is characterised by the decrease of Bcl-2 and consequent predominance of Bax. By contrast, in the normal T cells, which do not enter apoptosis, the quantitative relationship of Bcl-2 to Bax remains unchanged. The ability of betaGBP to selectively induce apoptosis in leukaemic cells suggests that betaGBP may play a role in cancer surveillance and that its use has potential therapeutic implications.


Assuntos
Apoptose/efeitos dos fármacos , Hemaglutininas/farmacologia , Células Jurkat/citologia , Linfócitos T/citologia , Proteína Ligante Fas , Citometria de Fluxo , Galectinas , Regulação Neoplásica da Expressão Gênica , Humanos , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Recombinantes/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Proteína X Associada a bcl-2 , Receptor fas/metabolismo
15.
J Immunol ; 161(5): 2114-9, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9725202

RESUMO

In this paper, the effects of beta-galactoside binding protein (beta GBP), the LGALS1 gene product, on the cell cycle progression and expansion of activated human T lymphocytes were studied. Beta GBP drastically inhibits the IL-2 induced proliferation of PHA-activated T lymphocytes as well as the IL-2 independent proliferation of malignant T lymphocytes by arresting them in the S and G2/M phases of the cell cycle. In addition, beta GBP up-regulates the expression of both the alpha- and the beta-chains of the IFN-gamma R on activated T lymphocyte membrane. None of these effects depend on sugar binding: saturating amounts of lactose do not affect the cell cycle block nor IFN-gamma R up-modulation. The increased expression of both chains renders beta GBP-treated T lymphoblasts sensitive to IFN-y-induced apoptosis. Taken as a whole, these findings suggest that beta GBP plays an important immunoregulatory role by switching off T lymphocyte effector functions. They also provide the first evidence of up-modulation of IFN-gamma R expression on T lymphocytes by a negative cell growth regulator.


Assuntos
Apoptose/imunologia , Ciclo Celular/imunologia , Hemaglutininas/farmacologia , Interferon gama/fisiologia , Lectinas/farmacologia , Receptores de Interferon/biossíntese , Linfócitos T/imunologia , Regulação para Cima/imunologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Galactosídeos/metabolismo , Galectina 1 , Hemaglutininas/metabolismo , Humanos , Interleucina-2/fisiologia , Lectinas/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Receptores de Interferon/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Timidina/metabolismo , Trítio , Regulação para Cima/efeitos dos fármacos , Receptor de Interferon gama
16.
Eur J Immunol ; 28(8): 2311-9, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9710209

RESUMO

We have used mRNA differential display PCR to search for genes induced in activated T cells and have found the LGALS1 (lectin, galactoside-binding, soluble) gene to be strongly up-regulated in effector T cells. The protein coded by the LGALS1 gene is a beta-galactoside-binding protein (betaGBP), which is released by cells as a monomeric negative growth factor but which can also associate into homodimers (galectin-1) with lectin properties. Northern blot analysis revealed that ex vivo isolated CD8+ effector T cells induced by a viral infection expressed high amounts of LGALS1 mRNA, whereas LGALS1 expression was almost absent in resting CD8+ T cells. LGALS1 expression could be induced in CD4+ and CD8+ T cells upon activation with the cognate peptide antigen and high levels of LGALS1 expression were found in concanavalin A-activated T cells but not in lipopolysaccharide-activated B cells. Gel filtration and Western blot analysis revealed that only monomeric betaGBP was released by activated CD8+ T cells and in vitro experiments further showed that recombinant betaGBP was able to inhibit antigen-induced proliferation of naive and antigen-experienced CD8+ T cells. Thus, these data indicate a role of betaGBP as an autocrine negative growth factor for CD8+ T cells.


Assuntos
Proteínas de Transporte/metabolismo , Galactosídeos/metabolismo , Hemaglutininas/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Antígenos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Sequência de Bases , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Transporte/genética , Divisão Celular , Linhagem Celular , Primers do DNA/genética , Galectinas , Inibidores do Crescimento/genética , Inibidores do Crescimento/metabolismo , Hemaglutininas/genética , Técnicas In Vitro , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Linfócitos T/citologia , Regulação para Cima
18.
Pacing Clin Electrophysiol ; 19(9): 1398-9, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8880810

RESUMO

Two years after implantation of an ICD with epicardial patch leads, a patient presented with hemoptysis. The posterior left ventricular patch was found to have eroded into lingular segmental bronchus. During thoracotomy, the hardware was removed and the bronchus successfully repaired.


Assuntos
Brônquios , Desfibriladores Implantáveis/efeitos adversos , Migração de Corpo Estranho , Idoso , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/cirurgia , Humanos , Masculino , Tomografia Computadorizada por Raios X
19.
Biochim Biophys Acta ; 1310(1): 81-5, 1996 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-9244179

RESUMO

Interferons play a part in the negative control of cell proliferation of mammalian cells. Here a natural interferon has been isolated from soluble proteins secreted by secondary murine embryonic fibroblasts using Blue Sepharose chromatography, immunoaffinity exclusion and Q Sepharose ion exchange fractionation. Partial amino acid sequencing assigns it to the interferon alpha family. Its biological and physico-chemical properties single it out from all other murine alpha interferons. The embryonic interferon has stronger antiproliferative activity, is acid labile, has stronger affinity for Blue Sepharose and weak affinity for antibodies which recognise other murine interferon alpha subtypes.


Assuntos
Embrião de Mamíferos/metabolismo , Interferon-alfa/isolamento & purificação , Sequência de Aminoácidos , Animais , Divisão Celular/efeitos dos fármacos , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Interferon-alfa/química , Interferon-alfa/farmacologia , Camundongos , Dados de Sequência Molecular
20.
Infect Immun ; 63(12): 4669-74, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7591121

RESUMO

Adherence of microorganisms to damaged heart tissue is a crucial event in the pathogenesis of infective endocarditis. In the present study, we investigated the role of the FimA protein as a potential virulence factor associated with Streptococcus parasanguis endocarditis. FimA is a 36-kDa surface protein that is a recognized adhesin in the oral cavity where it mediates adherence to the salivary pellicle. An insertion mutant and a deletion mutant of S. parasanguis were employed in the rat model of endocarditis to determine the relevance of FimA in endocarditis pathogenesis. Catheterized rats were infected with either the fimA deletion mutant VT929, the fimA insertion mutant VT930, or the isogenic, wild-type S. parasanguis FW213. Rats inoculated with FW213 developed endocarditis more frequently (50.9%) than animals inoculated with either the deletion mutant (2.7%) or the insertion mutant (7.6%) (P < 0.001). A series of in vitro assays were performed to explore the mechanism(s) by which FimA enhanced the infectivity of S. parasanguis. FimA did not inhibit the uptake or the subsequent killing of S. parasanguis by phagocytic granulocytes. Similarly, FimA did not play a role in the adherence to or the aggregation of platelets. Significant differences were noted between FW213 and VT929 (P < 0.05) and FW213 and VT930 (P < 0.001) in their abilities to bind to fibrin monolayers. The mean percent adherence of FW213 to fibrin monolayers (2.1%) was greater than those of VT929 (0.5%) and VT930 (0.12%). Taken together, these results indicate that FimA is a major virulence determinant associated with S. parasanguis endocarditis and further suggest that its role is associated with initial colonization of damaged heart tissue.


Assuntos
Proteínas de Bactérias/fisiologia , Endocardite Bacteriana/etiologia , Proteínas de Fímbrias , Infecções Estreptocócicas/etiologia , Animais , Aderência Bacteriana , Proteínas de Bactérias/genética , Película Dentária , Humanos , Masculino , Mutação , Adesividade Plaquetária , Agregação Plaquetária , Ratos , Ratos Sprague-Dawley , Streptococcus/patogenicidade , Virulência
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