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1.
J Robot Surg ; 17(6): 3013-3023, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37924415

RESUMO

Robotic-assisted surgery (RAS) is becoming increasingly common for the surgical treatment of rectal cancer. However, the use and implementation of robotic surgery remains controversial. This study aimed to compare the short-term outcomes of robotic surgery, focusing on pathological results and disease-free survival (DFS), in our cohort with initial robotic experience by multiple surgeon implementation. This retrospective study enrolled 571 patients diagnosed with rectal cancer, who were treated with chemoradiotherapy and surgery between January 2015 and December 2021. Surgical outcomes after RAS and laparoscopic surgery (LS) were compared using a propensity score-matching (PSM) analysis. After matching, 200 patients (100 in each group) were included. The median operative time was significantly longer in the RAS group than in the LS group (p < 0.001). The conversion and morbidity rates were similar between the groups. A significantly higher rate of complete mesorectal excision (92% vs. 72%; p = 0.001) and number of lymph nodes harvested (p = 0.009) was observed in the RAS group. There were no statistically significant differences between the groups regarding circumferential and distal resection margin involvement. The 3-year overall and disease-free survival rate was similar between the two groups (p = 0.849 and p = 0.582, respectively). Two patients in the LS group developed local recurrence and 27 patients (15.4%) developed metastatic disease. Multivariate analysis showed that tumor stage III was the only factor associated with disease-free survival (HR, 9.34; (95% CI 1.13-77.1), p = 0.038). RAS and LS showed similar outcomes in terms of perioperative, anatomopathological, and disease-free survival, after multiple surgeon implementations.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Cirurgiões , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Estudos Retrospectivos , Resultado do Tratamento , Pontuação de Propensão
4.
BMC Vet Res ; 15(1): 259, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31340824

RESUMO

BACKGROUND: Chlamydia abortus, an obligate intracellular pathogen with an affinity for placenta, causes reproductive failure. In non-pregnant animals, an initial latent infection is established until the next gestation, when the microorganism is reactivated, causing abortion. The precise mechanisms that trigger the awakening of C. abortus are still unknown. Sexual hormones such as estradiol and progesterone have been shown to affect the outcome of infection in other species of the family Chlamydiaceae, while estrogens increase chlamydial infection, progesterone has the opposite effect. To try to establish whether there is a relationship between these events and the latency/ reactivation of C. abortus in the reproductive tract of small ruminants, ovine endometrial (LE) and trophoblastic (AH-1) cells were treated with estradiol or progesterone prior to their infection with C. abortus. The results are compared with those obtained for treatment with penicillin prior to infection, which is a well-established model for studying persistent infection in other chlamydial species. Cells were examined by transmission electron microscopy, and an mRNA expression analysis of 16 genes related to the chlamydial developmental cycle was made. RESULTS: The changes observed in this study by the action of sex hormones seem to depend on the type of cell where the infection develops. In addition, while the changes are morphologically similar to those induced by treatment with penicillin, the patterns of gene expression are different. Gene expression patterns therefore, seem to depend on the persistence induced models of C. abortus used. Hormone treatments induced aberrant forms in infected endometrial cells but did not affect the chlamydial morphology in trophoblast cells. At the genetic level, hormones did not induce significant changes in the expression of the studied genes. CONCLUSIONS: The results suggest that penicillin induces a state of persistence in in vitro cultured C. abortus with characteristic morphological features and gene transcriptional patterns. However, the influence of hormones on the C. abortus developmental cycle is mediated by changes in the host cell environment. Furthermore, a persistent state in C. abortus cannot be characterised by a single profile of gene expression pattern, but may change depending on the model used to induce persistence.


Assuntos
Chlamydia/efeitos dos fármacos , Estradiol/farmacologia , Progesterona/farmacologia , Animais , Linhagem Celular , Chlamydia/crescimento & desenvolvimento , Chlamydia/ultraestrutura , Infecções por Chlamydia/veterinária , Feminino , Expressão Gênica , Microscopia Eletrônica de Transmissão/veterinária , Penicilinas/administração & dosagem , RNA Mensageiro , Ovinos
5.
Vet Immunol Immunopathol ; 213: 109887, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307668

RESUMO

Chlamydia abortus produces ovine enzootic abortion (OEA). Symptoms are not observed until the organism colonises the placenta, eventually causing abortion. Infected animals become carriers and will shed the organism in the following oestruses. This process suggests that sex hormones might play an important role in the physiopathology of OEA, affecting the success of chlamydial clearance and also jeopardising the effectiveness of vaccination. However, the mechanisms through which sex hormones are involved in chlamydial pathogenicity remain unclear. The aim of this study, therefore, was to determine the effect of progesterone on the immune response against C. abortus and on the protection conferred by an experimental inactivated vaccine in sheep. Eighteen sheep were ovariectomised and divided into four groups: vaccinated and progesterone-treated (V-PG), vaccinated and non-treated (V-NT), non-vaccinated and non-treated (NV-NT) and non-vaccinated and progesterone-treated sheep (NV-PG). Animals from both PG groups were treated with commercial medroxyprogesterone acetate impregnated intravaginal sponges before and during the vaccination (V-PG) or just before challenge (NV-PG). The animals from both V groups were subcutaneously immunised with an experimental inactivated vaccine, which was seen to confer high protection in previous studies. All sheep were challenged intratracheally with C. abortus strain AB7 and were sacrificed on day 8 post-infection. Morbidity was measured as the variation in rectal temperature and samples of sera were collected for antibody and cytokine (IFN-γ and IL-10) analysis by commercial ELISA. In addition, lung and lymph node samples were collected for chlamydial detection by qPCR and for histopathological and immunohistochemical analyses. Sheep from the V-PG group showed less severe or no lesions and lower morbidity than the other groups. They also had the highest abundance of regulatory T-cells. The sheep from V-NT also manifested high antibody levels against C. abortus and less severe lesions than those observed in non-vaccinated sheep, which showed high morbidity, low antibody levels and severe lesions, especially in NV-NT. These results confirm the effectiveness of the experimental vaccine employed and suggest that progesterone could enhance the effect.


Assuntos
Vacinas Bacterianas/uso terapêutico , Infecções por Chlamydia/veterinária , Imunidade Humoral , Progesterona/administração & dosagem , Doenças dos Ovinos/imunologia , Aborto Animal/imunologia , Aborto Animal/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Chlamydia/imunologia , Infecções por Chlamydia/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Ovinos , Doenças dos Ovinos/microbiologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/uso terapêutico
6.
Clin Microbiol Infect ; 19(7): 646-53, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22967234

RESUMO

In this prospective, multicentre cohort study, we analysed specific prognostic factors and the impact of timing of highly active antiretroviral therapy (HAART) on disease progression and death among 625 human immunodeficiency virus (HIV)-1-infected, treatment-naïve patients diagnosed with an AIDS-defining disease. HAART was classified as early (<30 days) or late (30-270 days). Deferring HAART was significantly associated with faster progression to a new AIDS-defining event/death overall (p 0.009) and in patients with Pneumocystis jiroveci pneumonia (p 0.017). In the multivariate analysis, deferring HAART was associated with a higher risk of a new AIDS-defining event/death (p 0.002; hazard ratio 1.83; 95% CI 1.25-2.68). Other independent risk factors for poorer outcome were baseline diagnosis of AIDS-defining lymphoma, age >35 years, and low CD4(+) count (<50 cells/µL).


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Antirretrovirais/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Síndrome da Imunodeficiência Adquirida/mortalidade , Síndrome da Imunodeficiência Adquirida/virologia , Adolescente , Adulto , Estudos de Coortes , Feminino , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Prognóstico , Estudos Prospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
J Comp Pathol ; 145(2-3): 107-17, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21334000

RESUMO

Caprine tuberculosis is caused by bacteria of the Mycobacterium tuberculosis complex (Mycobacterium bovis and Mycobacterium caprae). Although typical tuberculoid granulomata are usually observed in the lungs and lymph nodes of infected goats, the presence of cavitary lesions with exuberant mycobacterial growth is also a common feature in this species. The aim of this study was to characterize the immunological mechanisms that lead to liquefaction and cavity formation by comparing granulomata and cavitary lesions. Samples from animals positive by skin testing were collected for microscopical and immunohistochemical examination. Samples were also collected for analysis of cytokine gene expression in the lesions by real time polymerase chain reaction. There were marked differences between granulomata and cavitary lesions. In cavitary lesions there was a substantial population of neutrophils and a significant decrease in the number of CD4(+) T cells, with concomitant increases in other T-cell populations (CD8(+) and cells expressing the γδ form of the T-cell receptor). The enzyme iNOS was strongly expressed by macrophages in the cavitary lesions. There was no difference in the balance of pro- and anti-inflammatory cytokine gene expression in the lesions. These findings suggest that cavitary lesions are reactivation sites, where conditions are optimal for Mycobacterium proliferation and that immunological mechanisms may underlie the severe destruction of lung tissue that characterizes the cavitary pathology.


Assuntos
Doenças das Cabras/imunologia , Doenças das Cabras/patologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Tuberculose Pulmonar/veterinária , Animais , Expressão Gênica , Perfilação da Expressão Gênica , Cabras , Imuno-Histoquímica , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
An Med Interna ; 24(8): 393-5, 2007 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-18020881

RESUMO

Mesenteric Panniculitis is an inflammatory process, not tumoral, of the adipose tissue of the mesentery. There are documented several ways of clinical presentation, from asymptomatic until abdominal pain, affectation of general condition and loose weight. Exceptionally it is declared like only fever. Several treatments have been used, including colchicine, dapsone or corticosteroids associated or not with inmunosupresants, but there are no prospective controlled studies to define appropriate treatment; moreover, there are cases of regresion without specific therapy. Below we present the case of a patient affected for mesenteric panniculitis which the one clinical manifestation is fever predominance evening. The treatment with oral corticosteroids, for 2 years, resulted in the disappearance of the clinica.


Assuntos
Febre de Causa Desconhecida/etiologia , Paniculite Peritoneal , Administração Oral , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Humanos , Masculino , Mesentério/patologia , Pessoa de Meia-Idade , Paniculite Peritoneal/complicações , Paniculite Peritoneal/diagnóstico , Paniculite Peritoneal/diagnóstico por imagem , Paniculite Peritoneal/tratamento farmacológico , Paniculite Peritoneal/patologia , Radiografia Abdominal , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
Braz. j. med. biol. res ; 39(1): 9-18, Jan. 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-419148

RESUMO

Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doença da Artéria Coronariana , Teste de Esforço , Lógica Fuzzy , Seleção de Pacientes , Doença da Artéria Coronariana/classificação , Seguimentos , Modelos Teóricos , Perfusão , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
10.
Braz. j. med. biol. res ; 37(5): 755-764, May 2004. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-357551

RESUMO

In view of the importance of anticipating the occurrence of critical situations in medicine, we propose the use of a fuzzy expert system to predict the need for advanced neonatal resuscitation efforts in the delivery room. This system relates the maternal medical, obstetric and neonatal characteristics to the clinical conditions of the newborn, providing a risk measurement of need of advanced neonatal resuscitation measures. It is structured as a fuzzy composition developed on the basis of the subjective perception of danger of nine neonatologists facing 61 antenatal and intrapartum clinical situations which provide a degree of association with the risk of occurrence of perinatal asphyxia. The resulting relational matrix describes the association between clinical factors and risk of perinatal asphyxia. Analyzing the inputs of the presence or absence of all 61 clinical factors, the system returns the rate of risk of perinatal asphyxia as output. A prospectively collected series of 304 cases of perinatal care was analyzed to ascertain system performance. The fuzzy expert system presented a sensitivity of 76.5 percent and specificity of 94.8 percent in the identification of the need for advanced neonatal resuscitation measures, considering a cut-off value of 5 on a scale ranging from 0 to 10. The area under the receiver operating characteristic curve was 0.93. The identification of risk situations plays an important role in the planning of health care. These preliminary results encourage us to develop further studies and to refine this model, which is intended to implement an auxiliary system able to help health care staff to make decisions in perinatal care.


Assuntos
Humanos , Feminino , Recém-Nascido , Adolescente , Adulto , Asfixia Neonatal , Sistemas Inteligentes , Lógica Fuzzy , Ressuscitação , Tomada de Decisões , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Sensibilidade e Especificidade
11.
Braz. j. med. biol. res ; 37(5): 701-709, May 2004. tab, graf
Artigo em Inglês | LILACS | ID: lil-357553

RESUMO

The present study compares the performance of stochastic and fuzzy models for the analysis of the relationship between clinical signs and diagnosis. Data obtained for 153 children concerning diagnosis (pneumonia, other non-pneumonia diseases, absence of disease) and seven clinical signs were divided into two samples, one for analysis and other for validation. The former was used to derive relations by multi-discriminant analysis (MDA) and by fuzzy max-min compositions (fuzzy), and the latter was used to assess the predictions drawn from each type of relation. MDA and fuzzy were closely similar in terms of prediction, with correct allocation of 75.7 to 78.3 percent of patients in the validation sample, and displaying only a single instance of disagreement: a patient with low level of toxemia was mistaken as not diseased by MDA and correctly taken as somehow ill by fuzzy. Concerning relations, each method provided different information, each revealing different aspects of the relations between clinical signs and diagnoses. Both methods agreed on pointing X-ray, dyspnea, and auscultation as better related with pneumonia, but only fuzzy was able to detect relations of heart rate, body temperature, toxemia and respiratory rate with pneumonia. Moreover, only fuzzy was able to detect a relationship between heart rate and absence of disease, which allowed the detection of six malnourished children whose diagnoses as healthy are, indeed, disputable. The conclusion is that even though fuzzy sets theory might not improve prediction, it certainly does enhance clinical knowledge since it detects relationships not visible to stochastic models.


Assuntos
Humanos , Criança , Lógica Fuzzy , Pneumonia , Processos Estocásticos , Análise Discriminante , Análise Multivariada , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Biotechnol Bioeng ; 83(3): 249-59, 2003 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-12783481

RESUMO

A copy of the bovine chymosin gene (chy) with a codon usage optimized for its expression in Aspergillus awamori was constructed starting from synthetic oligonucleotides. To study the ability of this filamentous fungus to secrete bovine prochymosin, two plasmids were constructed in which the transcriptional, translational, and secretory control regions of the A. nidulans gpdA gene and pepB genes were coupled to either preprochymosin or prochymosin genes. Secretion of a protein enzymatically and immunologically indistinguishable from bovine chymosin was achieved in A. awamori transformants with each of these constructions. In all cases, the primary translation product (40.5 kDa) was self-processed to a mature chymosin polypeptide having a molecular weight of 35.6 kDa. Immunological assays indicated that most of the chymosin was secreted to the extracellular medium. Hybridization analysis of genomic DNA from chymosin transformants showed chromosomal integration of prochymosin sequences and, in some transformants, multiple copies of the expression cassettes were observed. Expression from the gpdA promoter was constitutive, whereas expression from the pepB promoter was strongly influenced by pH. A very high expression from the pepB promoter was observed during the growth phase. The A. awamori pepB gene terminator was more favorable for chymosin production than the S. cerevisiae CYC1 terminator.


Assuntos
Aspergillus/genética , Aspergillus/metabolismo , Quimosina/biossíntese , Quimosina/genética , Quimosina/metabolismo , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Sequência de Aminoácidos , Animais , Ácido Aspártico Endopeptidases/deficiência , Aspergillus/classificação , Bovinos , Quimosina/química , Clonagem Molecular , Precursores Enzimáticos/química , Regulação Fúngica da Expressão Gênica/genética , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Engenharia de Proteínas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Especificidade da Espécie , Transformação Genética
14.
Ann Allergy Asthma Immunol ; 87(6): 506-10, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11770699

RESUMO

BACKGROUND: The mechanism of nonsteroidal anti-inflammatory drug (NSAID)-induced reactions is unknown. However, strong evidence supports the hypothesis of an enhanced production of cysteinyl-leukotrienes. The existence of a polymorphism (A-444C) in the promoter region of the leukotriene (LT)C4-synthase gene (the terminal enzyme in the LTC4 production pathway) has been reported. This polymorphism has yielded contradictory results on its association with aspirin-induced asthma. OBJECTIVE: The present study was designed to investigate the possible genetic association of C(-444) allele and a specific clinical phenotype of NSAID sensitivity, the NSAID-induced isolated periorbital angioedema, via a case/control study. METHODS: The polymorphism A-444C was analyzed in 58 patients with NSAID-induced periorbital angioedema and 61 control subjects, who had undergone single-blind, placebo-controlled oral challenge. Genotype was determined by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: We have not found an association of C(-444), allele with NSAID-induced isolated periorbital angioedema. CONCLUSIONS: Further studies are needed to determine whether polymorphisms in the LTC4-synthase gene or other leukotriene-forming enzymes are involved in the pathogenesis of the different subsets of NSAID sensitivity.


Assuntos
Angioedema/induzido quimicamente , Anti-Inflamatórios não Esteroides/efeitos adversos , Glutationa Transferase/genética , Doenças Orbitárias/induzido quimicamente , Polimorfismo Genético/genética , Adolescente , Adulto , Angioedema/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Orbitárias/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Método Simples-Cego , Espanha
16.
Plant Mol Biol ; 42(3): 499-513, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10798619

RESUMO

A new MADS-box gene, STMADS16, has been cloned in Solanum tuberosum L. that is expressed in all vegetative tissues of the plant, mainly in the stem, but not in flower organs. STMADS16 expression is established early during vegetative development and is not regulated by light. Sequence similarity besides the spatial and temporal expression patterns allow to define a novel MADS-box subfamily comprising STMADS16 and the gene STMADS11. Expression of the STMADS16 sense cDNA under the control of the 35S cauliflower mosaic virus promoter modifies the inflorescence structure by increasing both internode length and flower proliferation of the inflorescence meristems, and confers vegetative features to the flower. Moreover, STMADS16 ectopic expression overcomes the increase in flowering time and node number produced under short-day photoperiod, while the flowering time is not affected in long-day conditions. These results are discussed in terms of a possible role for STMADS16 in promoting vegetative development.


Assuntos
Proteínas de Ligação a DNA/genética , Nicotiana/genética , Plantas Tóxicas , Solanum tuberosum/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Southern Blotting , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , DNA de Plantas/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas , Plantas Geneticamente Modificadas , RNA de Plantas/genética , RNA de Plantas/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Nicotiana/crescimento & desenvolvimento , Transformação Genética
17.
Ann Allergy Asthma Immunol ; 84(1): 43-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10674564

RESUMO

BACKGROUND: The oral administering of iron preparations sometimes produces adverse gastrointestinal effects. In contrast, cutaneous reactions are extremely rare. OBJECTIVE: We report a patient with several episodes of generalized pruritus and erythematous maculopapular eruption after receiving oral compounds of iron and on whom desensitization with oral iron was attempted. METHODS: We studied a female with microcytic anemia due to gynecologic blood loss who presented several episodes of cutaneous eruption after receiving oral compounds of iron. Skin prick-test and two simple-blind, placebo-controlled oral challenges were performed with various iron compounds, and finally desensitization with oral iron was carried out. RESULTS: Skin prick-test and patch-test with iron preparations were negative. Two simple-blind, placebo-controlled oral challenges were performed and the patient began experiencing similar cutaneous symptoms. We started a slow desensitization protocol using increasing doses until the target amount of the drug was tolerated without adverse effects. The chronic administration of oral iron therapy once a day for 9 months sustained the desensitized state and the anemia disappeared. CONCLUSION: We present methods to effectively manage iron supply for a microcytic anemia patient with cutaneous reactions due to oral iron compounds, to avoid repeated transfusions, slow desensitization with oral iron was successfully attempted.


Assuntos
Toxidermias/etiologia , Ferro/efeitos adversos , Administração Oral , Adulto , Anemia Ferropriva/tratamento farmacológico , Feminino , Humanos , Método Simples-Cego
18.
Blood ; 94(7): 2301-9, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10498602

RESUMO

In adult bone marrow, hematopoietic stem cells are found in close association with distinctive stromal cell elements. This association is necessary for maintenance of hematopoiesis, but the precise mechanisms underlying the cross-talk between stromal cells and hematopoietic stem cells are poorly understood. In this study, we used a bone marrow stromal cell line (MS-5) that is able to support human long-term hematopoiesis. This hematopoietic-promoting activity cannot be related to expression of known cytokines and is abolished by addition of hydrocortisone. Using a gene trap strategy that selects genes encoding transmembrane or secreted proteins expressed by MS-5 cells, we obtained several insertions that produced fusion proteins. In one clone, fusion protein activity was downregulated in the presence of hydrocortisone, and we show that insertion of the trap vector has occurred into the neuropilin-1 gene. Neuropilin-1 is expressed in MS-5 cells, in other hematopoietic-supporting cell lines, and in primary stromal cells but not in primitive hematopoietic cells. We show that neuropilin-1 acts as a functional cell-surface receptor in MS-5 cells. Two neuropilin-1 ligands, semaphorin III and VEGF 165, can bind to these cells, and the addition of VEGF 165 to MS-5 cells increases expression of 2 cytokines known to regulate early hematopoiesis, Tpo and Flt3-L. Finally, we show that stromal cells and immature hematopoietic cells express different neuropilin-1 ligands. We propose that neuropilin-1 may act as a novel receptor on stromal cells by mediating interactions between stroma and primitive hematopoietic cells.


Assuntos
Células da Medula Óssea/citologia , Regulação da Expressão Gênica/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Proteínas do Tecido Nervoso/genética , Receptores de Superfície Celular/genética , Células Estromais/fisiologia , Transfecção/métodos , Adulto , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Comunicação Celular , Técnicas de Cultura de Células/métodos , Cricetinae , Fatores de Crescimento Endotelial/metabolismo , Fatores de Crescimento Endotelial/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos , Células-Tronco Hematopoéticas/citologia , Humanos , Hidrocortisona/farmacologia , Linfocinas/metabolismo , Linfocinas/farmacologia , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/biossíntese , Neuropilina-1 , Receptores de Superfície Celular/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/citologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
Ann Allergy Asthma Immunol ; 82(2): 194-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10071524

RESUMO

BACKGROUND: Tobacco is a plant belonging to the Solanaceae family. This plant is usually used as a contact insecticide for several infestations in some areas, such as the Canary Islands. Allergy induced by inhalation of this plant is unusual. Identification of the potential allergen in growing areas is essential. OBJECTIVE: We report a patient with occupational sensitivity to an aqueous solution of cut tobacco whose clinical manifestations were rhinoconjunctivitis and urticaria. Past medical history was significant for seasonal allergic rhinoconjunctivitis to mugwort pollen and oral allergy syndrome with avocado. METHODS: Green tobacco and cured tobacco leaf extracts were prepared, skin prick tests were performed with green tobacco, cured tobacco leaf extracts, and certain aeroallergens. Conjunctival challenge test was carried out with green tobacco and cured tobacco leaf extract. Serum-specific IgE against tobacco leaf was performed by commercial CAP. CAP inhibition experiments were carried out with tobacco and Artemisia vulgaris. RESULTS: Skin prick tests and conjunctival challenge tests with green tobacco and cured tobacco leaf extracts were positive, as well as serum-specific IgE by CAP, indicating an IgE-mediated sensitization. CAP inhibition experiments were carried out and it was found that tobacco, mugwort pollen, and tomato extracts inhibited the binding of the patient's serum to solid-phase tobacco leaf. No inhibition was observed when Alternaria, D. pteronyssinus, and potato were used as control inhibitors. Inhibition of immunoCAP to mugwort was obtained with mugwort and tobacco extracts and no cross-reactivity to D. pteronyssinus was shown. CONCLUSION: The results suggest that tobacco can induce IgE-mediated reactions that are mediated by the existence of common antigenic epitopes between tobacco and mugwort pollen. This allergy can be a hazard of employment in the agricultural areas.


Assuntos
Doenças dos Trabalhadores Agrícolas/etiologia , Alérgenos/imunologia , Hipersensibilidade Imediata/etiologia , Inseticidas/efeitos adversos , Nicotiana/imunologia , Plantas Tóxicas , Pólen/imunologia , Solanaceae/imunologia , Adulto , Doenças dos Trabalhadores Agrícolas/imunologia , Alternaria/imunologia , Conjuntivite Alérgica/etiologia , Conjuntivite Alérgica/imunologia , Reações Cruzadas , Dermatite Ocupacional/etiologia , Dermatite Ocupacional/imunologia , Humanos , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Inseticidas/imunologia , Lauraceae/imunologia , Masculino , Extratos Vegetais/imunologia , Folhas de Planta/imunologia , Rinite Alérgica Sazonal/etiologia , Rinite Alérgica Sazonal/imunologia , Testes Cutâneos , Fumaça/efeitos adversos , Solanaceae/classificação , Especificidade da Espécie , Poluição por Fumaça de Tabaco , Urticária/etiologia , Urticária/imunologia
20.
Front Biosci ; 4: D141-52, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9924144

RESUMO

A considerable progress has been made during the past years in elucidating the molecular actors of angiogenesis. Vascular endothelial growth factor turned out to represent the major inducer of angiogenesis. Optional splicing of its pre messenger RNA generates various isoforms which differ not only by their storage in the extracellular matrix but also by their signaling pathways. VEGF binds and activates two tyrosine kinase receptors called VEGFR1 and VEGFR2 and neuropilin-1. The elucidation of the transduction pathways of each receptor suggests that VEGFR1 mediates cell migration whereas VEGFR2 mediates cell proliferation. The construction of internal images of VEGF by the anti-idiotypic antibody strategy allowed us to determine that quiescent endothelial cells need to be activated by so far unknown factors to become competent to respond to mitogenic signals and acquire an angiogenic phenotype. The discovery of the mechanisms of action of the VEGF system has allowed the design of promising drugs which already entered the pre-clinical or clinical assays.


Assuntos
Fatores de Crescimento Endotelial/fisiologia , Linfocinas/fisiologia , Neovascularização Patológica/fisiopatologia , Neovascularização Fisiológica/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Transdução de Sinais , Animais , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Regulação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Linfocinas/genética , Linfocinas/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Receptores Proteína Tirosina Quinases/química , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/química , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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