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1.
Eur J Clin Microbiol Infect Dis ; 42(1): 33-42, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36346471

RESUMO

The accuracy of contemporary risk scores in predicting perioperative mortality in infective endocarditis (IE) remains controversial. The aim is to evaluate the performance of existent mortality risk scores for cardiovascular surgery in IE and the impact on operability at high-risk thresholds. A single-center retrospective review of adult patients diagnosed with acute left-sided IE undergoing surgery from May 2014 to August 2019 (n = 142) was done. Individualized risk calculation was obtained according to the available mortality risk scores: EuroScore I and II, PALSUSE, Risk-E, Costa, De Feo-Cotrufo, AEPEI, STS-risk, STS-IE, APORTEI, and ICE-PCS scores. A cross-validation analysis was performed on the score with the best area under the curve (AUC). The 30-day survival was 96.5% (95%CI 91-98%). The score with worse area under the curve (AUC = 0.6) was the STS-IE score, while the higher was for the RISK-E score (AUC = 0.89). The AUC of the majority of risk scores suggested acceptable performance; however, statistically significant differences in expected versus observed mortalities were common. The cross-validation analysis showed that a large number of survivors (> 75%) would not have been operated if arbitrary high-risk threshold estimates had been used to deny surgery. The observed mortality in our cohort is significantly lower than is predicted by contemporary risk scores. Despite the reasonable numeric performance of the analyzed scores, their utility in judging the operability of a given patient remains questionable, as demonstrated in the cross-validation analysis. Future guidelines may advise that denial of surgery should only follow a highly experienced Endocarditis Team evaluation.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Endocardite Bacteriana , Endocardite , Adulto , Humanos , Estudos de Coortes , Medição de Risco , Fatores de Risco , Endocardite/diagnóstico , Endocardite/cirurgia , Estudos Retrospectivos
2.
Public Health ; 185: 8-14, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32505041

RESUMO

OBJECTIVES: Opioid overdose death rates have continued to spike exponentially from the start of the 21st century, creating what is known to be one of the worst public health crises in the United States. Simultaneously, as more states began passing medical cannabis laws (MCLs), the idea that marijuana was the solution to the opioid crisis began to spread nationwide. As some states have maintained strict medical marijuana policies, others-such as Colorado-have expanded their statutes to allow recreational marijuana sales within their state. Researchers have been able to provide sense of the public health implications resulting from MCLs, but little is known about the effects of this marijuana policy expansion. This preliminary study will focus on exploring the statewide effects of Colorado's recreational marijuana policy on the state's opioid overdose death rates. STUDY DESIGN: Because Colorado has existing panel data for opioid overdose death rates, we can use statistical software to define and create an optimal control group to adequately resemble Colorado's outcome variable of interest. This process known as the synthetic control method can provide a valid counterfactual for Colorado's opioid overdose outcomes in the absence of this policy-a Colorado that did not expand marijuana policy to the point recreational dispensaries were established. METHODS: Opioid overdose death rate data from the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research (WONDER) will be used to construct a synthetic control unit composed of a donor pool of states resembling Colorado's regulatory environment pertaining to marijuana before legalization. The synthetic control unit allows for a comparative observation of overdose rate trends in Colorado and its synthetic counterpart for the years 1999-2017, all while including a set of predictor variables for robustness checks. A difference-in-difference estimate will then help us observe the effects of the treatment given to Colorado. Inference tests will be conducted to evaluate the method's predictive power and significance of the results. RESULTS: The results of the synthetic control model and its outcomes showed that the estimated negative 5% drop in overdose death rates was deemed insignificant on conducting a placebo in-space analysis, meaning there is not enough evidence to prove that opening recreational dispensaries as a result of recreational marijuana legislation was instrumental in reducing Colorado's ongoing opioid crisis depicted through opioid overdose deaths. CONCLUSION: Owing to the lack of additional post-treatment data and captured lagged effects, it is too soon to dismiss this policy as inadequate in combating the opioid epidemic. Once additional post-treatment data become available, the study can be reproduced to obtain more robust results and achieve a clearer understanding of the policy implications shown.


Assuntos
Analgésicos Opioides/intoxicação , Overdose de Drogas/epidemiologia , Uso da Maconha/epidemiologia , Uso da Maconha/legislação & jurisprudência , Adulto , Cannabis , Centers for Disease Control and Prevention, U.S. , Colorado/epidemiologia , Humanos , Legislação de Medicamentos , Maconha Medicinal , Pessoa de Meia-Idade , Epidemia de Opioides , Saúde Pública , Política Pública , Análise Espacial , Estados Unidos
3.
Bull Entomol Res ; 108(5): 602-615, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29166979

RESUMO

Insect fauna biodiversity in natural protected areas has not been thoroughly studied. Therefore, the aim of this work was to assess whether and how vegetation types, land management and seasonality influence the diversity of Ichneumonidae (Hymenoptera) in the Ría Lagartos Biosphere Reserve (Mexico). A sampling programme was conducted using Malaise traps from 2008 to 2009 in three vegetation types, each with two conservation zones (core and buffer zones). Three seasons were considered: rainy, dry and north-winds (isolated storms from November to February). A total of 336 species were identified. Rarefaction and Generalized Linear Model indicated higher species richness and abundance, respectively, in the buffer zone of the dry forest; possible explanations for this finding include the intermediate disturbance hypothesis, wherein diversity can be higher in sites where disturbance is not very frequent or very intense, and the 'enemies hypothesis', wherein structural complexity and high plant diversity favour increased predators or, in this case, parasitoids. Diversity was higher during the rainy season, which may have been due to the higher availability of resources. Vegetation and management had a positive impact on the Coc (attack cocoons and pupae) and Myc (attack concealed larvae living in the fruiting bodies of mushrooms) parasitoid guilds. Members of the Coc guild are generalist parasitoids, which may be favoured in complex vegetation with a high richness of potential hosts and non-hosts. The Myc guild requires certain environmental conditions that promote fungal growth, such as humidity, that is absent in the other vegetation types of savannah and coastal dune scrubland.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Himenópteros/fisiologia , Animais , Interações Hospedeiro-Parasita , México , Parques Recreativos , Estações do Ano
4.
Cont Lens Anterior Eye ; 38(5): 317-21, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25899637

RESUMO

PURPOSE: To evaluate the power profile within the optic zone of different designs of multifocal contact lenses (CLs) and to analyze how the effect of pupil size could impact on their optical performance. METHODS: The optical power distribution within the optic zones of multifocal CLs was measured by the Nimo TR1504 (LAMBDA-X, Belgium). The multifocal CLs under study were the Acuvue Bifocal, the Acuvue Oasys for Presbyopia, the PureVision Multifocal and the PureVision 2 for Presbyopia. Each design was considered in all their available addition powers. All lenses had a nominal power of -3.0D. At the same time, three lenses of each model were considered and five consecutive readings of each lens were performed. RESULTS: The results show that the PureVision Multifocal and the PureVision 2 for Presbyopia have aspheric power profiles. Both designs showed aspheric center-near designs with a smoother progression of the optical power in the PureVision 2 for Presbyopia. The Acuvue Bifocal and the Acuvue Oasys for Presbyopia are shown to have concentric alternating near and far zones. Apart from the refractive rings, the Acuvue Oasys for Presbyopia showed an increase in negative (or less positive) values toward the periphery of the lens. CONCLUSIONS: Besides the refraction, the knowledge of the power profiles of multifocal CLs and the effect of pupil size on the optical distribution of these lenses could be crucial to understand the performance of these designs when they are fitted.


Assuntos
Lentes de Contato/classificação , Iris/anatomia & histologia , Luz , Presbiopia/reabilitação , Refratometria/instrumentação , Espalhamento de Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
5.
Ann Thorac Surg ; 65(6): 1784-6, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9647108

RESUMO

We report a case of lipomatous hypertrophy of the interatrial septum in a patient with a recent syncopal episode and shortness of breath. Preoperative transesophageal echocardiography demonstrated a large tumor protruding from the interatrial septum. In addition, the patient was found to have significant coronary artery disease and a right internal carotid artery stenosis. The patient underwent successful resection of the mass with septal reconstruction, aortocoronary bypass, and right carotid endarterectomy. Histology of the mass was consistent with lipomatous hypertrophy.


Assuntos
Septos Cardíacos/cirurgia , Lipomatose/cirurgia , Cardiomiopatias/complicações , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/cirurgia , Artéria Carótida Interna/cirurgia , Estenose das Carótidas/complicações , Estenose das Carótidas/cirurgia , Ponte de Artéria Coronária , Doença das Coronárias/complicações , Doença das Coronárias/cirurgia , Dispneia/etiologia , Ecocardiografia Transesofagiana , Endarterectomia das Carótidas , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Septos Cardíacos/diagnóstico por imagem , Humanos , Hipertrofia , Lipomatose/complicações , Lipomatose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Síncope/etiologia
6.
Ann Thorac Surg ; 69(2): 621-3, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10735715

RESUMO

We describe a patient who sustained a traumatic rupture of an aberrant right subclavian artery. An interposition graft was used to restore continuity of the artery to the descending thoracic aorta.


Assuntos
Artéria Subclávia/anormalidades , Artéria Subclávia/lesões , Adulto , Aorta Torácica/cirurgia , Aortografia , Implante de Prótese Vascular , Humanos , Masculino , Ruptura , Artéria Subclávia/cirurgia
7.
Arch Med Res ; 29(4): 279-84, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9887543

RESUMO

Infection with high-risk human papillomavirus (HPV) types is involved in early stages of uterine=cervix cancer development. The virally encoded E6 and E7 oncoproteins behave as tumor-specific antigens and represent targets for a vaccine designed to control HPV-induced tumors. Using either proteins or peptides based on E6 and E7 oncoproteins of HPV16 and 18, phase I clinical trials of therapeutic vaccines against HPV-associated cervical cancers have recently been reported. Although the effectiveness of these vaccines cannot be evaluated in such small studies, they constitute an important step toward the development of therapeutic uterine=cervix cancer vaccines. A polytope DNA vaccination approach combined with immunomodulatory cytokines may offer an excellent strategy to reduce the risk of relapse and metastasis following conventional therapies.


Assuntos
Vacinas Anticâncer/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/imunologia , Feminino , Humanos , Proteínas Oncogênicas Virais/imunologia , Papillomaviridae/imunologia
8.
Rev Invest Clin ; 42 Suppl: 28-31, 1990 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-19256129

RESUMO

The cytokines are proteins synthetized by lymphoid and monocyte/macrophage system cells in response to a wide variety of infectious stimulus, featuring bacterial endotoxins. These proteins have immunoregulatory effects and have been implicated in inflammation and fibrosis. In this review we refer to the interleukin-1, interleukin-6 and tumor necrosis factor because of their elevated basal levels in acute and chronic hepatopaties and in response to lipopolisacharide mainly in alcoholic liver disease.


Assuntos
Citocinas/fisiologia , Fígado/fisiologia , Endotoxemia/fisiopatologia , Humanos , Infecções/fisiopatologia , Interleucina-1/fisiologia , Interleucina-6/fisiologia , Leucócitos/metabolismo , Hepatopatias/fisiopatologia , Células Mieloides/metabolismo , Fator de Necrose Tumoral alfa/fisiologia
9.
Rev Gastroenterol Mex ; 43(1): 1-8, 1978.
Artigo em Espanhol | MEDLINE | ID: mdl-715342

RESUMO

One case of the association of primary biliar cirrhosis and systemic sclerosis progressive (SSP) is described (Reynold's syndrome). This association has been reported in 21 patients. In our case the signs of liver disease precede two years the appearence of SSP. A review of the patients with Reynold's syndrome reported is done and compared with the present case. Diagnostic approach and management of this association is also discussed.


Assuntos
Cirrose Hepática Biliar/patologia , Escleroderma Sistêmico/patologia , Pele/patologia , Colchicina/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Cirrose Hepática Biliar/tratamento farmacológico , Pessoa de Meia-Idade , Escleroderma Sistêmico/tratamento farmacológico , Síndrome
10.
Eye (Lond) ; 28(5): 614-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24556881

RESUMO

PURPOSE: To assess the optical performance of the new EnVista intraocular lens (IOL). MATERIALS AND METHODS: Four aspheric IOLs were evaluated; the new EnVista is one amoung them. This IOL, similarly to the Z-Flex HB and the Bi-Flex 1.8 667AB ones, has a neutral aspheric design, whereas the fourth IOL under test (AcrySof IQ IOL SN60WF) presents a negative spherical aberration (SA). The IOL's aberration patterns were measured in vitro, by setting them up on an optical bench. From these aberration-pattern data, the modulation transfer function (MTF), the average modulation values, and the points spread function (PSF) were calculated. Furthermore, in order to assess the potential optical quality that these IOLs would yield once they are implanted, an average corneal-aberration pattern was juxtaposed to the in-vitro profiles and the same parameters were calculated again. RESULTS: For the IOL-only scenario (ie, without including the corneal factor), it was the EnVista IOL, which is aberration-free that showed the higher MTF, PSF values. This was followed by the other two aberration-free IOL models. However, when the effect of an average corneal pattern was also taken into consideration, the AcrySof IQ IOL SN60WF always outperformed the other neutral-asphericity IOLs. CONCLUSIONS: The in-vitro optical performance of the EnVista IOL was good, but it decreases substantially in a whole-eye scenario, when the wavefront profile of an average cornea is added. Other designs with different degrees of SA should be considered for this IOL in order to surpass these results.


Assuntos
Lentes Intraoculares/normas , Desenho de Prótese , Aberrações de Frente de Onda da Córnea , Humanos , Óptica e Fotônica
11.
Environ Entomol ; 41(3): 587-93, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22732617

RESUMO

The biology and behavior of insects are strongly influenced by environmental conditions such as temperature and precipitation. Because some of these factors present a within day variation, they may be causing variations on insect diurnal flight activity, but scant information exists on the issue. The aim of this work was to describe the patterns on diurnal variation of the abundance of Ichneumonoidea and their relation with relative humidity, temperature, light intensity, and wind speed. The study site was a tropical dry forest at Ría Lagartos Biosphere Reserve, Mexico; where correlations between environmental factors (relative humidity, temperature, light, and wind speed) and abundance of Ichneumonidae and Braconidae (Hymenoptera: Ichneumonoidea) were estimated. The best regression model for explaining abundance variation was selected using the second order Akaike Information Criterion. The optimum values of temperature, humidity, and light for flight activity of both families were also estimated. Ichneumonid and braconid abundances were significantly correlated to relative humidity, temperature, and light intensity; ichneumonid also showed significant correlations to wind speed. The second order Akaike Information Criterion suggests that in tropical dry conditions, relative humidity is more important that temperature for Ichneumonoidea diurnal activity. Ichneumonid wasps selected toward intermediate values of relative humidity, temperature and the lowest wind speeds; while Braconidae selected for low values of relative humidity. For light intensity, braconids presented a positive selection for moderately high values.


Assuntos
Ritmo Circadiano , Meio Ambiente , Voo Animal , Vespas/fisiologia , Animais , Agentes de Controle Biológico , Feminino , Masculino , México , Especificidade da Espécie , Luz Solar , Tempo (Meteorologia)
12.
J Clin Gastroenterol ; 31(1): 89-90, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10914787

RESUMO

A series of reports in the literature suggest that video assisted thoracoscopic resection of an esophageal leiomyoma offers distinct advantage over open approach. We describe a patient with esophageal leiomyoma who underwent surgical resection via thoracoscopic approach using four thoracic trocars. The postoperative period was uneventful and the patient was discharged on postoperative day 3.


Assuntos
Neoplasias Esofágicas/cirurgia , Leiomioma/cirurgia , Toracoscopia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Prensa Med Mex ; 41(7-8): 231-4, 1976.
Artigo em Espanhol | MEDLINE | ID: mdl-13359

RESUMO

A case of a 44 years old man with the unique combination of polyarteritis nodosa (PAN) and the congenital absence of a kidney is presented. The clinical picture consisted of fever, general symptoms, hypertermia, peripheric neuropathy, subcutaneous nodules and renal damage. Laboratory findings included increased WBC, telescoped urinary sediment, renal insufficiency, positive rheumatoid factor, policlonal gammopathy and positive Australia antigen. A review of the pertinent literature and the etiopathogenic role of Australia antigen in PAN is discussed. Efficacy of immunosuppressive therapy was evident in this case.


Assuntos
Rim/anormalidades , Poliarterite Nodosa/complicações , Adulto , Biópsia , Clorambucila/uso terapêutico , Anormalidades Congênitas/complicações , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/tratamento farmacológico , Diagnóstico Diferencial , Humanos , Masculino , Poliarterite Nodosa/diagnóstico , Poliarterite Nodosa/tratamento farmacológico , Prednisona/uso terapêutico
14.
Prensa Med Mex ; 43(1-2): 16-20, 1978.
Artigo em Espanhol | MEDLINE | ID: mdl-309127

RESUMO

Forty three patients with systemic lupus erythematosus (SLE) were divided into three groups, inactive, active without treatment and active on treatment with steroids. T lymphocytes from peripheral blood were determined and the results compared with those of twenty five normal individuals. In further experiments, the mitogenic capacity of SLE lymphocytes to Con A and the serum's activity of these patients upon normal lymphocytes were analized. Decreased T lymphocytes were found in all groups of patients with SLE. There were no difference between the mitogenic response of SLE patients and controls when the lymphocytes were incubated with normal human AB serum. When normal lymphocytes were incubated with serum from SLE patients with active disease, and inhibition of mitogenic response to Con A was observed. These results suggests that the decrease cellular immunity observed in SLE is due to serum factors rather than to intrinsic T cell abnormality.


Assuntos
Imunidade Celular , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Formação de Anticorpos , Linfócitos B/imunologia , Concanavalina A/farmacologia , Feminino , Humanos , Imunidade Celular/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Mitose/efeitos dos fármacos , Prednisona/uso terapêutico , Linfócitos T/imunologia
15.
Bol Med Hosp Infant Mex ; 35(5): 803-11, 1978.
Artigo em Espanhol | MEDLINE | ID: mdl-687402

RESUMO

Two patients with Osgood-Schlatter's disease studied at the Unidad de Pediatría Hospital General de México are reported. Both with the same ago, sex and clinical symptoms. No surgery was performed. Several considerations are made on etiology, clinical, radiologic and histopathological aspects. Treatment is discussed and a complete review of medical literature is made.


Assuntos
Osteocondrite , Criança , Humanos , Joelho/cirurgia , Perna (Membro)/diagnóstico por imagem , Masculino , Osteocondrite/diagnóstico por imagem , Osteocondrite/cirurgia , Radiografia
16.
Bol Med Hosp Infant Mex ; 33(6): 1345-76, 1976.
Artigo em Espanhol | MEDLINE | ID: mdl-1008931

RESUMO

The present article describes the main surgical pathology of the newborn, which often requires immediate management. The author(s) mention the essential points of diagnosis and treatment. The principal objective in the article is to emphasize the importance of this surgical pathology in pediatric and general practice.


Assuntos
Anormalidades Congênitas/diagnóstico por imagem , Doenças do Recém-Nascido/diagnóstico por imagem , Anormalidades Congênitas/cirurgia , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/cirurgia , Masculino , Radiografia , Fatores de Tempo
17.
J Rheumatol ; 6(2): 196-203, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-379330

RESUMO

Forty-four uninvolved skin biopsies from lupus patients and 43 with various connective tissue diseases and nephritides other than lupus were tested for the presence of immunoglobulin deposition in the dermal-epidermal junction. Results were examined to determine their relationship to renal and clinical activity. Lupus band test (LBT) was positive in 30 (60%) SLE patients regardless of renal or clinical status. DNA-binding (p less than 0.01) and ANA (p less than 0.002) correlated to LBT. None of the other nephritides and only 2 with other connective tissue diseases were positive. LBT is a good aid in the differential diagnosis of SLE regardless of clinical or renal activity.


Assuntos
Imunofluorescência , Lúpus Eritematoso Sistêmico/diagnóstico , Testes Cutâneos , Adolescente , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Nefropatias/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade
18.
Clin Exp Immunol ; 47(1): 110-8, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6178542

RESUMO

Natural cytotoxicity (NK) by fresh E-rosette-negative (ER-) cells from normal donors was increased after overnight incubation with purified IFN alpha and with supernatants containing IFN gamma. ER- cells from 61% of 23 patients with systemic lupus erythematosus did not show increased cytotoxicity after treatment with IFN alpha. Similarly, ER- cells from nine of 18 patients that were treated with IFN gamma-containing supernatants failed to show increased cytotoxicity. The patients who did not show enhanced cytotoxic responses to IFN had higher mean indices of disease activity than responding patients.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Interferons/farmacologia , Células Matadoras Naturais/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Células Cultivadas , Feminino , Humanos , Imunidade Inata , Células Matadoras Naturais/efeitos dos fármacos , Pessoa de Meia-Idade , Formação de Roseta
19.
Environ Res ; 33(2): 428-40, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6370674

RESUMO

Protozoa of nose, mouth, and pharynx of 30 randomly chosen female caries patients at an odontological clinic of the National Autonomous University of Mexico, were surveyed by culture from swabs. Culture tubes of swabs from each patient were observed every other day during 5 weeks. Pathogenic protozoa found included Entamoeba histolytica Schaudinn, 1903; Naegleria fowleri Carter, 1970; Acanthamoeba castelanii Douglas, 1930; Acanthamoeba culbertsoni Singh & Das, 1970; and Balantidium coli (Malmsten, 1857) Stein, 1862. This isolation of pathogens suggests that healthy patients may be healthy carriers of cysts of protozoa, mainly amoebae, responsible for several diseases, including primary amoebic meningoencephalitis. Small pathogenic free-living amoebae have not been isolated before from females in Mexico. Many species of free-living protozoa were also cultured from swabs from the patients.


Assuntos
Eucariotos/isolamento & purificação , Boca/microbiologia , Mucosa Nasal/microbiologia , Faringe/microbiologia , Adulto , Clínicas Odontológicas , Feminino , Imunofluorescência , Humanos , México
20.
Int Immunol ; 12(5): 607-12, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10784606

RESUMO

We report the identification of a human cDNA encoding a 25 kDa protein of relevant evolutionary and lymphoid interest (PRELI). PRELI was cloned by screening a B lymphocyte-specific cDNA library with a probe generated by mRNA differential display. PRELI amino acid sequence is 85% similar to the avian px19 protein, expressed within the blood islands and in the liver during avian embryo development. PRELI and px19 contain tandem repeats (A/TAEKAK) of the late embryogenesis abundant (LEA) motif, characteristic of a group of survival molecules and originally thought to be present only in plant proteins. Interestingly, PRELI expression is high in the fetal liver, a major site for B cell lymphopoiesis, while the mRNA levels in other fetal tissues such as the brain, lung, and kidney are comparatively low. At the adult stage, PRELI expression is drastically reduced in the liver but exhibits high mRNA levels in the spleen, brain, lung and kidney tissues, suggesting that PRELI expression may be important for the development of vital and immunocompetent organs. Moreover, PRELI is also highly expressed in the adult lymph nodes and peripheral blood leukocytes, further stressing that at the adult stage, PRELI expression may be important during secondary immune responses. Consistent with this hypothesis, the expression of PRELI is predominant within germinal centers (GC), a stage in which B lymphocytes are under a stressful selection pressure. Taken together these data: (i) strongly support the notion that the conserved LEA motif represents a phylogenetic link between plants and animals, (ii) reveal a novel molecule whose expression may play a role in the maturation of distinct human tissues, and (iii) suggest that PRELI expression may be important for GC B lymphocytes.


Assuntos
Linfócitos B/imunologia , Centro Germinativo/imunologia , Proteínas/genética , Adulto , Sequência de Aminoácidos , Animais , Northern Blotting , Linhagem Celular , DNA Complementar/genética , Evolução Molecular , Feto , Humanos , Proteínas Mitocondriais , Dados de Sequência Molecular , Codorniz , RNA Mensageiro/análise , Alinhamento de Sequência , Vísceras/metabolismo
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