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1.
Arch Med Res ; 53(6): 625-633, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36109203

RESUMO

BACKGROUND: The true prevalence of Chagas disease in Mexico is unknown. However, it has been estimated that 1.1-4 million people are infected with Trypanosoma cruzi, which represents a potential risk for transmission of the disease via contaminated blood. AIM OF THE STUDY: To determine the Chagas disease seroprevalence in donors from eight blood banks in the north of Mexico City, and the northeast of the State of Mexico. STUDY DESIGN AND METHODS: Serum samples from blood donors (n = 515,038) were tested to detect the presence of anti-Trypanosoma cruzi antibodies in eight blood banks. The serologic screening test was performed in each of the blood banks. To confirm the seropositive blood donors, only two out of the eight blood banks used a test with a different principle with the aim of identifying anti-Trypanosoma cruzi antibodies. All tests were validated by the Mexican Institute for Epidemiological Diagnosis and Reference. RESULTS: One thousand two hundred and ten blood donors were seropositive for Trypanosoma cruzi, which represents a 0.23% seroprevalence (95% CI 0.22-0.25%). Of the seropositive blood donors, 97.03 % resided in the northeast area of the State of Mexico, Mexico City, and southern part of the State of Hidalgo. CONCLUSIONS: Active transmission of Chagas disease may be occurring in non-endemic regions in the northeast of the State of Mexico.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Anticorpos Antiprotozoários , Bancos de Sangue , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Humanos , México/epidemiologia , Estudos Soroepidemiológicos
2.
Materials (Basel) ; 13(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348736

RESUMO

The review presented herein is regarding the stress corrosion cracking (SCC) phenomena of carbon steel pipelines affected by the corrosive electrolytes that comes from external (E) and internal (I) environments, as well as the susceptibility and tensile stress on the SCC. Some useful tools are presented including essential aspects for determining and describing the E-SCC and I-SCC in oil and gas pipelines. Therefore, this study aims to present a comprehensive and critical review of a brief experimental summary, and a comparison of physicochemical, mechanical, and electrochemical data affecting external and internal SCC in carbon steel pipelines exposed to corrosive media have been conducted. The SCC, hydrogen-induced cracking (HIC), hydrogen embrittlement, and sulfide stress cracking (SSC) are attributed to the pH, and to hydrogen becoming more corrosive by combining external and internal sources promoting cracking, such as sulfide compounds, acidic soils, acidic atmospheric compounds, hydrochloric acid, sulfuric acid, sodium hydroxide, organic acids (acetic acid, mainly), bacteria induced corrosion, cathodic polarization, among others. SCC growth is a reaction between the microstructural, chemical, and mechanical effects and it depends on the external and internal environmental sources promoting unpredictable cracks and fractures. In some cases, E-SCC could be initiated by hydrogen that comes from the over-voltage during the cathodic protection processes. I-SCC could be activated by over-operating pressure and temperature at flowing media during the production, gathering, storage and transportation of wet hydrocarbons through pipelines. The mechanical properties related to I-SCC were higher in comparison with those reviewed by E-SCC, suggesting that pipelines suffer more susceptibility to I-SCC. When a pipeline is designed, the internal fluid being transported (changes of environments) and the external environment concerning SCC should be considered. This review offers a good starting point for newcomers into the field, it is written as a tutorial, and covers a large number of basic standards in the area.

3.
Materials (Basel) ; 13(3)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033021

RESUMO

To date, the formation mechanisms of TiO2, as well as its heterostructures, have not been clarified. Moreover, detailed research on the transition from a tetragonal anatase phase to the monoclinic phase of the TiO2(B) phase and their interface structure has been quite limited until now. In the present study, we report on the sonochemical synthesis of TiO2-anatase with a crystallite size of 5.2 ± 1.5 nm under different NaOH concentrations via the hydrothermal method. The use of alkaline solution and the effect of the temperature and reaction time on the formation and structural properties of TiO2-anatase nanopowders were studied. The effects of NaOH concentration on the formation and transformation of titanate structures are subject to thermal effects that stem from the redistribution of energy in the system. These mechanisms could be attributed to three phenomena: (1) the self-assembly of nanofibers and nanosheets, (2) the Ostwald ripening process, and (3) the self-development of hollow TiO2 mesostructures.

4.
Materials (Basel) ; 12(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31756925

RESUMO

This paper reports the production of intermetallic microrods and microtubes from the decomposition of an intermetallic compound in an AlTiFe system. The intermetallic compound was obtained by mechanosynthesis of elemental powders of Al, Ti and Fe over 300 h at 400 rpm, sintering from compacted powder particles at 300 MPa per minute and at 900 °C for 3600 s in an argon atmosphere. The milled and sintered samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The intermetallic AlTi3 and Fe3Al phases were obtained during the milling process. After sintering, a decomposition of these intermetallic phases was found-Al3Ti0.75Fe0.25, Al3Ti, FeTi, AlTi3, Ti9Al23, Fe2Ti, Al86Fe14 and Al0.4Fe0.6. As a result of the decomposition, we observed the formation of hexagonal rods with intercalated phases of AlTi3 and Fe2Ti.

5.
Inflamm Res ; 66(9): 775-781, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28500376

RESUMO

OBJECTIVE: The functional PTPN22 R620W polymorphism (rs2476601) is clearly associated with susceptibility to several autoimmune diseases (ADs). However, the PTPN22 R263Q polymorphism (rs33996649) has been scarcely explored in different ADs. Here we aimed to examine the associations of the PTPN22 R620W and R263Q polymorphisms with susceptibility to or protection against rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and Graves' disease (GD) among Mexican patients. METHODS: We conducted a case-control study including 876 patients (405 with SLE, 388 with RA, and 83 with GD) and 336 healthy control individuals. PTPN22 genotypes were determined using the TaqMan 5' allele discrimination assay. RESULTS: PTPN22 R620W was associated with GD susceptibility (OR 4.3, p = 0.004), but was not associated with SLE (OR 1.8, p = 0.19). We previously demonstrated that this polymorphism is associated with RA susceptibility (OR 4.17, p = 0.00036). Moreover, PTPN22 R263Q was associated with protection against SLE (OR 0.09, p = 004) and RA (OR 0.28, p = 0.045), but was not associated with GD. CONCLUSIONS: Our data provide the first demonstration that PTPN22 R620W confers GD susceptibility among Latin-American patients. Moreover, this is the second report documenting the association of PTPN22 R263Q with protection against SLE and RA.


Assuntos
Artrite Reumatoide/genética , Doença de Graves/genética , Lúpus Eritematoso Sistêmico/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Adulto , Artrite Reumatoide/epidemiologia , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Doença de Graves/epidemiologia , Hispânico ou Latino/genética , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
7.
Sci Transl Med ; 4(138): 138ra78, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22700954

RESUMO

The translation of "next-generation" sequencing directly to the clinic is still being assessed but has the potential for genetic diseases to reduce costs, advance accuracy, and point to unsuspected yet treatable conditions. To study its capability in the clinic, we performed whole-exome sequencing in 118 probands with a diagnosis of a pediatric-onset neurodevelopmental disease in which most known causes had been excluded. Twenty-two genes not previously identified as disease-causing were identified in this study (19% of cohort), further establishing exome sequencing as a useful tool for gene discovery. New genes identified included EXOC8 in Joubert syndrome and GFM2 in a patient with microcephaly, simplified gyral pattern, and insulin-dependent diabetes. Exome sequencing uncovered 10 probands (8% of cohort) with mutations in genes known to cause a disease different from the initial diagnosis. Upon further medical evaluation, these mutations were found to account for each proband's disease, leading to a change in diagnosis, some of which led to changes in patient management. Our data provide proof of principle that genomic strategies are useful in clarifying diagnosis in a proportion of patients with neurodevelopmental disorders.


Assuntos
Exoma/genética , Feminino , Humanos , Masculino , Mutação , Linhagem , Análise de Sequência de DNA , Proteínas de Transporte Vesicular/genética
8.
Mycopathologia ; 174(3): 247-54, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22396010

RESUMO

This study was conducted to evaluate the possible protector effect of bentonite and zeolite in Bovans chicks fed a diet containing 59 mg kg(-1) of fumonisin B1 (FB1) during 3 weeks. A total of 200 one-day-old male chicks were treated varying the amount of bentonite and zeolite. Chick weight was registered weekly. At the end of the experiment, all the chicks were killed, and the livers were analyzed for gross examination and histopathological changes. Plasmatic activity of alanine amino transferase and aspartate amino transferase (AST) were also determined. Sphinganine and the sphinganine-to-sphingosine ratio in serum were evaluated. Both, bentonite and zeolite showed a protector effect against FB1 adsorption in the digestive tract of chicks. Chicks fed with FB1-contaminated feed, amended either with zeolite or bentonite, were heavier, and no macroscopic lesions were observed in the livers. AST activity might be considered as an indicator for FB1 exposition because AST levels were affected when only FB1 was present in the basal diet. These results indicate that both, zeolite and bentonite can be added into feed to diminish the effects of FB1.


Assuntos
Antitoxinas/administração & dosagem , Bentonita/administração & dosagem , Fumonisinas/antagonistas & inibidores , Fumonisinas/toxicidade , Zeolitas/administração & dosagem , Administração Oral , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal , Galinhas , Dieta/métodos , Histocitoquímica , Fígado/patologia , Masculino , Esfingosina/análogos & derivados , Esfingosina/sangue
9.
Nat Genet ; 44(2): 193-9, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22246503

RESUMO

Tubulin glutamylation is a post-translational modification that occurs predominantly in the ciliary axoneme and has been suggested to be important for ciliary function. However, its relationship to disorders of the primary cilium, termed ciliopathies, has not been explored. Here we mapped a new locus for Joubert syndrome (JBTS), which we have designated as JBTS15, and identified causative mutations in CEP41, which encodes a 41-kDa centrosomal protein. We show that CEP41 is localized to the basal body and primary cilia, and regulates ciliary entry of TTLL6, an evolutionarily conserved polyglutamylase enzyme. Depletion of CEP41 causes ciliopathy-related phenotypes in zebrafish and mice and results in glutamylation defects in the ciliary axoneme. Our data identify CEP41 mutations as a cause of JBTS and implicate tubulin post-translational modification in the pathogenesis of human ciliary dysfunction.


Assuntos
Doenças Cerebelares/genética , Cílios/genética , Transtornos da Motilidade Ciliar/genética , Anormalidades do Olho/genética , Ácido Glutâmico/metabolismo , Doenças Renais Policísticas/genética , Proteínas/genética , Tubulina (Proteína)/metabolismo , Animais , Centrossomo/metabolismo , Mapeamento Cromossômico , Cílios/metabolismo , Feminino , Loci Gênicos , Humanos , Masculino , Camundongos , Mutação , Peptídeo Sintases/metabolismo , Polimorfismo de Nucleotídeo Único , Processamento de Proteína Pós-Traducional , Síndrome
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