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Abstract Ligustrazine is widely used for the treatment of cardiovascular diseases in traditional Chinese medication. It has been reported that Ligustrazine decreases the concentration of intracellular calcium ions (Ca2+); however, the underlying mechanism remains unknown. In the present study, the effect of Ligustrazine on adenosine diphosphate (ADP)-induced platelet aggregation was evaluated using a turbidimetric approach. The changes in concentration of intracellular Ca2+ stimulated by ADP was measured using fluo-4, a fluorescent Ca2+ indicator dye. The mRNA expression of stromal interaction molecule l (STIM1) and Orai1, calcium sensor, was determined using real-time PCR. In addition, the protein expression of STIM1, Orai1, and serum/glucocorticoid-regulated protein kinase 1 (SGK1) was determined using Western blot analysis. The data demonstrated that Ligustrazine significantly suppressed platelet aggregation in a dose-dependent manner and reduced the concentration of intracellular Ca2+ triggered by ADP. Our data showed that Ligustrazine treatment inhibited the expression of STIM1 and Orai1 induced by ADP at both mRNA and protein levels, and suppressed the protein expression of SGK1. Taken together, our data indicated that Ligustrazine suppressed platelet aggregation by partly inhibiting the activities of calcium sensors, thereby suggesting that Ligustrazine may be a promising candidate for the treatment of platelet aggregation.
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Animales , Masculino , Ratas , Proteínas Quinasas , Enfermedades Cardiovasculares/patología , Agregación Plaquetaria , Adenosina Difosfato/farmacología , Western Blotting/métodos , Calcio/agonistas , Pueblo Asiatico/clasificación , Moléculas de Interacción EstromalRESUMEN
BACKGROUND: Tumor infiltrating lymphocytes (TILs) and regression are thought to be distinct markers of the immune response to melanoma. OBJECTIVE: This study sought to analyze the relationship of TIL grade and presence of regression to each other and to other prognostic histopathologic and clinical values in melanoma. MATERIALS AND METHODS: A retrospective analysis was conducted using patients diagnosed with melanoma between 2013 and 2019 whose complete histopathologic reports were available. RESULTS: Regression was seen in 48.9%, 30.1% and 37.9% of patients with brisk, non-brisk, and absent TILs respectively (P=0.019). Melanoma tumors with brisk TILs were found to have a lower Breslow thickness than those with non-brisk or absent (P= 0.001). Tumors with regression were also found to have lower Breslow thickness (P<0.001). Neither TIL grade nor regression were protective of nodal metastasis or associated with improved survival. CONCLUSION: Brisk TILs have a positive association with thinner tumors and the presence of tumor regression relative to non-brisk or absent TILs. This may suggest a more robust immune response in tumors with brisk TILs. Further exploration of the interplay between TIL grade, lymphocyte cell subtype and lymphocyte density may help explain this finding.
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Melanoma , Neoplasias Cutáneas , Humanos , Linfocitos Infiltrantes de Tumor , Melanoma/patología , Pronóstico , Estudios Retrospectivos , Neoplasias Cutáneas/patologíaRESUMEN
SiTian is an ambitious ground-based all-sky optical monitoring project, developed by the Chinese Academy of Sciences. The concept is an integrated network of dozens of 1-m-class telescopes deployed partly in China and partly at various other sites around the world. The main science goals are the detection, identification and monitoring of optical transients (such as gravitational wave events, fast radio bursts, supernovae) on the largely unknown timescales of less than 1 day; SiTian will also provide a treasure trove of data for studies of AGN, quasars, variable stars, planets, asteroids, and microlensing events. To achieve those goals, SiTian will scan at least 10,000 square deg of sky every 30 min, down to a detection limit of $V \approx 21$ mag. The scans will produce simultaneous light-curves in 3 optical bands. In addition, SiTian will include at least three 4-m telescopes specifically allocated for follow-up spectroscopy of the most interesting targets. We plan to complete the installation of 72 telescopes by 2030 and start full scientific operations in 2032.
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Planetas , Telescopios , China , Análisis EspectralRESUMEN
Abstract Lonicera japonica Thunb., Caprifoliaceae, has been employed in traditional Chinese medicine for thousands of years. However, it is frequently confused with closely related species, and thus, a mixture of these species is commonly used. The sources of Lonicera species must be accurately and rapidly determined to ensure the clinical efficacy of herbal medicines. Attenuated total reflectance Fourier transform infrared spectroscopy and high-performance liquid chromatography with a diode array detector, combined with chemometrics methods, were used to comprehensively evaluate the Lonicera quality. The infrared fingerprint results indicated that the spectra of L. japonica and its related species were very similar in the range 4000-1800 cm-1, however a large number of chemical absorption peaks were observed in the region 1800-600 cm-1 with certain differences. The five Lonicera species had high chlorogenic acid (25.85-67.75 µg/mg), 3,5-di-O-caffeoylquinic acid (11.63-62.58 µg/mg), and 4,5-di-O-caffeoylquinic acid (2.64-30.91 µg/mg) contents. The chemical fingerprints of L. hypoglauca Miq. and L. confusa DC were the most similar to that of L. japonica Thunb. The chemical fingerprints of L. fulvotomentosa P.S. Hsu & S.C. Cheng and L. macranthoides Hands.-Mazz. were very different from that of L. japonica. A loading analysis indicated that the differences in the chemical fingerprints of the Lonicera species were mainly due to variations in the contents of the organic acids and flavonoids. Soft independent modeling of class analogy model was successfully developed to classify unknown samples of the five Lonicera species. This comprehensive, unbiased strategy provides adequate, reliable scientific evidence for authenticating herbal sources, therefore offering a powerful, new route for herbal analysis.
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As a support material, zeolite can be used to promote the granulation process due to its high settable property and the ability to retain biomass on its surface. The present paper reports on the influence of zeolite addition on the hydrodynamic behavior of an expanded granular sludge bed reactor (EGSB). Different models were applied to fit the flow pattern and to compare EGSB hydrodynamic performance with and without the addition of zeolite. The experimental data fit the tanks in a series model for zeolite bed height of 5cm and upflow velocity of 6m/hr. Higher axial dispersion degree (D/uL) was obtained at lower heights of zeolite. The real hydraulic retention time (HRTr) was increased with both increased zeolite bed height and increased upflow velocity. The short-circuit results for 5cm of zeolite bed and 6, 8 and 10m/hr upflow velocity were 0.3, 0.24 and 0.19 respectively, demonstrating the feasibility of using zeolite for a proper hydrodynamic environment to operate the EGSB reactor. The presence of zeolite resulted in the higher percentage values of dead zones, ranging from 12% to 24%. Zeolite addition exerted a positive effect on the hydrodynamics pattern for this technology being advantageous for the anaerobic process because of its possible contribution to better biofilm agglomeration, granule formation and substrate-microorganism contact.
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Reactores Biológicos , Eliminación de Residuos Líquidos/métodos , Anaerobiosis , Hidrodinámica , Modelos Teóricos , Aguas del AlcantarilladoRESUMEN
OBJECTIVES: Skin adnexal carcinoma (SAC) is a rare cutaneous malignancy that arises from sebaceous and sweat glands. These carcinomas are believed to behave more aggressively than cutaneous squamous cell carcinomas (SCC) with a propensity for local recurrence. The role of adjuvant radiotherapy in SAC is undefined. METHODS: We retrospectively reviewed all cases of head and neck SAC treated with surgery and adjuvant radiation from 2000 to 2012 at a single institution. RESULTS: Nine cases were identified. Median age was 67 (range, 52 to 88) years. The histologies were: adnexal carcinoma (n=1), adnexal carcinoma with sebaceous differentiation (n=1), adnexal carcinoma with squamous differentiation (n=1), skin appendage carcinoma (n=1), sclerosing sweat duct carcinoma (n=1), mucinous carcinoma (n=1), ductal eccrine adenocarcinoma (n=1), porocarcinoma (n=1), and trichilemmal carcinoma (n=1). All tumors were reviewed by a dermatopathologist to confirm the SAC diagnosis.All patients had undergone surgery. Indications for adjuvant radiation included involved lymph nodes (n=4), perineural invasion (n=2), nodal extracapsular extension (n=2), positive margin (n=1), high-grade histology (n=6), multifocal disease (n=2), and/or recurrent disease (n=5). Radiation was delivered to the primary site alone (n=3), to the draining lymphatics alone (n=2), or to both (n=4). One patient received concurrent cisplatin. Median dose to the primary site was 60 Gy and to the neck was 50 Gy.Median follow-up was 4.0 years (range, 0.6 to 11.4 y). Locoregional control was 100%. Five-year progression-free survival was 89%. There was 1 acute grade 3 toxicity and no greater than or equal to grade 2 late toxicities were recorded. CONCLUSIONS: Surgery and adjuvant radiation for high-risk SAC offers excellent locoregional control with acceptable toxicity.
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Neoplasias de Cabeza y Cuello/terapia , Neoplasias de Anexos y Apéndices de Piel/terapia , Radioterapia Adyuvante/métodos , Anciano , Anciano de 80 o más Años , Terapia Combinada , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Disección del Cuello , Recurrencia Local de Neoplasia , Neoplasias de Anexos y Apéndices de Piel/mortalidad , Neoplasias de Anexos y Apéndices de Piel/patología , Neoplasias de Anexos y Apéndices de Piel/cirugía , Estudios RetrospectivosRESUMEN
This study investigated the effects of warming yang and invigorating qi prescription on renin-angiotensin-aldosterone system (RAAS) in rats with heart failure after myocardial infarction. 126 rats were randomly divided into model group, sham operation, warming yang, invigorating qi, warming yang+invigorating qi, digoxin and captopril group for respective treatment. After intervention for 6, 8 and 10 weeks, the left ventricular ejection fraction (LVEF) was calculated, and the plasma renin, angiotensin II and aldosterone levels were measured. Results showed that, after 6, 8 and 10 weeks, LVEF in warming yang, invigorating qi, warming yang+invigorating qi and captopril group was significantly higher than model group (P < 0.05), and the plasma renin, angiotensin II and aldosterone levels in warming yang, invigorating qi, warming yang+invigorating qi and captopril groups were significantly lower than model group (P < 0.05). Renin angiotensin II and aldosterone levels in invigorating qi, warming yang+invigorating qi and captopril groups after 10 weeks was significantly lower than after 6 weeks (P < 0.05); aldosterone level in captopril groups after 10 weeks was significantly lower than after 6 weeks (P < 0.05). Warming yang and invigorating qi prescription can improve LVEF in rats with heart failure after myocardial infarction, which may be related with the inhibition of RAAS activation.(AU)
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Animales , Insuficiencia Cardíaca , Sistema Renina-Angiotensina , Cardiopatías , Medicina Tradicional China , Infarto del Miocardio , Ratas , Volumen SistólicoRESUMEN
AbstractObjective:The aim of the current study was to evaluate the early experience of the application of transcatheter aortic valve implantation with the balloon-expandable system in China. The transcatheter aortic valve implantation technology has been widely used for patients with inoperable severe aortic stenosis in the developed world. The application of transcatheter aortic valve implantation is still in the early stages of testing in China, particularly for the balloon-expandable valve procedure.Methods:This was a retrospective study. All patients undergoing transcatheter aortic valve implantation with balloon-expandable system in our hospital between 2011 and 2014 were included. Edwards SAPIEN XT Transcatheter Heart Valve was used. The improvement of valve and heart function was evaluated as well as 30-day mortality and major complications according to the VARC-2 definition.Results:A total of 10 transcatheter aortic valve implantation procedures with the balloon-expandable system were performed in our hospital, of which 9 were transfemoral and 1 was transapical. The median age was 76 years, and the median STS score and Logistic EuroSCORE (%) were 8.9 and 16.2. The implantation was successfully conducted in all patients, only 2 patients had mild paravalvular leak. There was no second valve implantation. Moreover, no 30-day mortality or complications was reported. Following the transcatheter aortic valve implantation procedure, the heart and valve functions had improved significantly. During the follow-up period of 3-34 months, one patient died of lung cancer 13 months after the operation.Conclusion:This early experience has provided preliminary evidence for the safety and efficacy of transcatheter aortic valve implantation procedure with the balloon-expandable system in the developing world with an increasing aging population.
ResumoObjetivo:O objetivo do presente estudo foi avaliar a experiência inicial da aplicação do implante percutâneo da válvula aórtica com o sistema balão-expansível na China. A tecnologia TAVI tem sido amplamente utilizada para pacientes com estenose aórtica grave inoperável no mundo desenvolvido. A aplicação de implante percutâneo da válvula aórtica está ainda nas etapas iniciais de teste na China, em particular o procedimento de válvula balão-expansível.Métodos:O estudo foi retrospectivo e todos os pacientes submetidos a implante percutâneo da válvula aórtica com sistema balão-expansível em nosso hospital entre 2011 e 2014 foram incluídos. Edwards SAPIEN XT Válvula Cardíaca Transcatheter foi usado. A melhoria do funcionamento da válvula e do coração foi avaliada, bem como mortalidade em 30 dias e as principais complicações de acordo com a definição VARC-2.Resultados:Um total de 10 procedimentos Tavi com o sistema balão-expansível foram realizados em nosso hospital, dos quais 9 foram transfemorais e 1 foi transapical. A idade média foi de 76 anos, e os STS mediana marcar e Logistic EuroSCORE (%) foram de 8,9 e 16,2. A implantação foi realizada com sucesso em todos os pacientes, apenas 2 pacientes tiveram vazamento paravalvar leve. Não houve um futuro implante valvar. Além disso, mortalidade em 30 dias ou complicações não foram relatadas. Seguindo o procedimento de implante percutâneo da válvula aórtica, as válvulas cardíacas e funções melhoraram significativamente. Durante o período de acompanhamento de 3-34 meses, um paciente morreu de câncer de pulmão 13 meses após a operação.Conclusão:Esta experiência inicial apresentou elementos de prova preliminar para a segurança e eficácia do procedimento implante percutâneo da válvula aórtica com o sistema balão-expansível no mundo em desenvolvimento com crescente envelhecimento da população.
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Anciano , Femenino , Humanos , Masculino , Estenosis de la Válvula Aórtica/terapia , Valvuloplastia con Balón/métodos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Angiografía , Estenosis de la Válvula Aórtica , China/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/mortalidadRESUMEN
OBJECTIVE: The aim of the current study was to evaluate the early experience of the application of transcatheter aortic valve implantation with the balloon-expandable system in China. The transcatheter aortic valve implantation technology has been widely used for patients with inoperable severe aortic stenosis in the developed world. The application of transcatheter aortic valve implantation is still in the early stages of testing in China, particularly for the balloon-expandable valve procedure. METHODS: This was a retrospective study. All patients undergoing transcatheter aortic valve implantation with balloon-expandable system in our hospital between 2011 and 2014 were included. Edwards SAPIEN XT Transcatheter Heart Valve was used. The improvement of valve and heart function was evaluated as well as 30-day mortality and major complications according to the VARC-2 definition. RESULTS: A total of 10 transcatheter aortic valve implantation procedures with the balloon-expandable system were performed in our hospital, of which 9 were transfemoral and 1 was transapical. The median age was 76 years, and the median STS score and Logistic EuroSCORE (%) were 8.9 and 16.2. The implantation was successfully conducted in all patients, only 2 patients had mild paravalvular leak. There was no second valve implantation. Moreover, no 30-day mortality or complications was reported. Following the transcatheter aortic valve implantation procedure, the heart and valve functions had improved significantly. During the follow-up period of 3-34 months, one patient died of lung cancer 13 months after the operation. CONCLUSION: This early experience has provided preliminary evidence for the safety and efficacy of transcatheter aortic valve implantation procedure with the balloon-expandable system in the developing world with an increasing aging population.
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Estenosis de la Válvula Aórtica/terapia , Valvuloplastia con Balón/métodos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Anciano , Angiografía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , China/epidemiología , Femenino , Humanos , Masculino , Estudios Retrospectivos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Resultado del TratamientoRESUMEN
Peptidoglycan recognition proteins (PGRPs) are innate immune molecules that have been structurally conserved throughout evolution in invertebrates and vertebrates. In this study, peptidoglycan recognition protein HcPGRP1 and its isoform HcPGRP1a were identified in the freshwater mussel Hyriopsis cumingii. The full-length cDNAs of HcPGRP1 (973 bp) and HcPGRP1a (537 bp) encoded polypeptides with 218 and 151 amino acids, respectively. Sequence analysis showed that HcPGRP1 had one C-terminal PGRP domain that was conserved throughout evolution. Phylogenetic analysis showed that HcPGRP1 clustered closely with EsPGRP4 of Euprymna scolopes. Real-time PCR showed that the mRNA transcripts of HcPGRP1 and HcPGRP1a were constitutively expressed in various tissues, with the highest level in hepatopancreas. Stimulation with lipopolysaccharide (LPS) and peptidoglycan (PGN) significantly up-regulated HcPGRP1 mRNA expression in hepatopancreas and foot, but not in gill, whereas HcPGRP1a expression was significantly up-regulated in all three tissues. Our results indicate that HcPGRP1 is both a constitutive and inducible protein that may be involved in immune responses (recognition and defense) against invaders.
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The clavulanic acid is a substance which inhibits the ß-lactamases used with penicillins for therapeutic treatment. After the fermentation, by-products of low molecular weight such as amino acids lysine, histidine, proline and tyrosine are present in the fermented broth. To remove these impurities the techniques of extraction by an aqueous two-phase system of 17% polyethylene glycol molecular weight 600 and 15% potassium phosphate were used for a partial purification. A subsequent ion-exchange adsorption was used for the recuperation of the clavulanic acid of the top phase and purification getting a concentration factor of 2 and purification of 100% in relation to the amino acids lysine, histidine, proline and tyrosine.
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Ácido Clavulánico/aislamiento & purificación , Medios de Cultivo/química , Streptomyces/crecimiento & desarrollo , Adsorción , Aminoácidos/química , Ácido Clavulánico/biosíntesis , Ácido Clavulánico/química , Intercambio Iónico , Streptomyces/metabolismoRESUMEN
BACKGROUND: Porcine circovirus type 2 (PCV2), the causative agent of postweaning multisystemic wasting syndrome (PMWS), is a serious economic problem in the swine industry. Different genotypes (PCV2a, PCV2b and PCV2d) of the virus are present in the clinical cases in China, and it is necessary to elucidate the pathogenic difference among different genotypes of PCV2. In this study, four strains of different genotypes were isolated, two were ordinary strains and another two were mutation strains, which there are one and two amino acids elongation in the capsid protein (Cap) of PCV2, respectively. Representative strains of different genotypes of the virus were constructed by infectious molecular clone and biological characterization of the rescued viruses were identified in vitro. RESULTS: Four PCV2 isolates (PCV2a/CL, PCV2b/YJ, PCV2b/JF and PCV2d/BDH) of different genotypes were isolated from the clinical cases of PMWS in China. Four infectious clones of PCV2 were constructed and the rescued viruses were harvested after transfection into PK15 cells. The rescued viruses were verified by nucleotide sequence analysis, morphology of the viruses and immunoperoxidase monolayer assay (IPMA). The rescued viruses propagated stably after consecutive incubation for more than ten passages, and virus propagation reached its peak 72h post infection (PI), and the virus titers were up to 105·7 TCID50/ml. By using neutralizing 1D2 monoclonal antibody (mAb) of PCV2, the antigen capture ELISA showed that only the PCV2a/rCL and PCV2b/rJF strains has immunoreactivity with the 1D2 mAb, however, another two rescued strains (PCV2b/rYJ and PCV2d/rBDH) do not, which indicated the antigenic difference among the rescued viruses of different genotypes. In addition, here is the first report of obtaining the newly emerging PCV2 with mutation in vitro by infectious molecular clone technology. CONCLUSIONS: Conclusions drawn from this study show that PCV2 has prevailing differences in genomic and ORF2 gene length and antigen in swine herds in China. Four representative clones for different genotypes were constructed and rescued, which will facilitate further studies on the pathogenic differences resulting from different subtypes of PCV2.
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Circovirus/genética , Circovirus/patogenicidad , ADN Viral/genética , Ingeniería Genética/métodos , Recombinación Genética , Virología/métodos , Animales , Proteínas de la Cápside/genética , Línea Celular , China , Circovirus/aislamiento & purificación , Genotipo , Mutagénesis Insercional , PorcinosRESUMEN
Gallic acid was artificially added to the media to grow Fusarium oxysporum f.sp.niveum to investigate its effect on the pathogenic fungus. Results indicate that gallic acid inhibited the growth of F. oxysporum f.sp.niveum. The colony diameter, the conidia germinating rate and the conidia yield were reduced by 5.7-22.9%%, 35.8-55.6% and 38.9-62.2% respectively. However, the virulence factors by the fungus were stimulated. The activity of pectinase, proteinase and cellulase increased by 12.3-627.8%, 11.8-41.2% and 0.5-325.0% respectively, while the activity of amylase increased slightly. The results suggest that gallic acid repressed growth but facilitated the relative pathogenicity of invading pathogens.
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Medios de Cultivo/farmacología , Fusarium/efectos de los fármacos , Ácido Gálico/farmacología , Esporas Fúngicas/efectos de los fármacos , Recuento de Colonia Microbiana , Medios de Cultivo/química , Fusarium/crecimiento & desarrollo , Fusarium/patogenicidad , Esporas Fúngicas/crecimiento & desarrollo , Esporas Fúngicas/patogenicidad , Factores de VirulenciaRESUMEN
OBJECTIVE: To examine the relation between income and oral cancer incidence in countries at different stages of economic development. DESIGN: Descriptive study with regression analysis of oral cancer incidence in relation to real gross domestic product (GDP) per capita from 1970 to 2000 performed for 8 different countries. METHODS: GDP per capita was collected from the United States, Hong Kong, Singapore, Italy, Mexico, Philippines, Poland, and Romania. Correlation factor and Pearson values were compared. RESULTS: The association between income and the oral cavity cancer rate was significant in all the countries selected. Using linear regression analysis, the results showed high r2 value. The increase of real GDP correlated negatively with the rate of male oral cavity cancer in the United States, Italy, Hong Kong, and Singapore but not in Mexico, Philippines, Poland, and Romania. CONCLUSIONS: The association between incidence and income appears to depend on per capita GDP, being negative in countries with GDP above US$10,000 and positive in countries with GDP below US$10,000.
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Renta , Neoplasias de la Boca/epidemiología , Estudios Transversales , Países Desarrollados/estadística & datos numéricos , Países en Desarrollo/estadística & datos numéricos , Hong Kong/epidemiología , Humanos , Incidencia , Italia/epidemiología , Modelos Lineales , Masculino , México/epidemiología , Filipinas/epidemiología , Polonia/epidemiología , Rumanía/epidemiología , Singapur/epidemiología , Factores Socioeconómicos , Estados Unidos/epidemiologíaRESUMEN
The study of the biology of evolution has been confined to laboratories and model organisms. However, controlled laboratory conditions are unlikely to model variations in environments that influence selection in wild populations. Thus, the study of "fitness" for survival and the genetics that influence this are best carried out in the field and in matching environments. Therefore, we studied highland populations in their native environments, to learn how they cope with ambient hypoxia. The Andeans, African highlanders and Himalayans have adapted differently to their hostile environment. Chronic mountain sickness (CMS), a loss of adaptation to altitude, is common in the Andes, occasionally found in the Himalayas; and absent from the East African altitude plateau. We compared molecular signatures (distinct patterns of gene expression) of hypoxia-related genes, in white blood cells (WBC) from Andeans with (n = 10), without CMS (n = 10) and sea-level controls from Lima (n = 20) with those obtained from CMS (n = 8) and controls (n = 5) Ladakhi subjects from the Tibetan altitude plateau. We further analyzed the expression of a subset of these genes in Ethiopian highlanders (n = 8). In all subjects, we performed the studies at their native altitude and after they were rendered normoxic. We identified a gene that predicted CMS in Andeans and Himalayans (PDP2). After achieving normoxia, WBC gene expression still distinguished Andean and Himalayan CMS subjects. Remarkably, analysis of the small subset of genes (n = 8) studied in all 3 highland populations showed normoxia induced gene expression changes in Andeans, but not in Ethiopians nor Himalayan controls. This is consistent with physiologic studies in which Ethiopians and Himalayans show a lack of responsiveness to hypoxia of the cerebral circulation and of the hypoxic ventilatory drive, and with the absence of CMS on the East African altitude plateau.
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Adaptación Fisiológica/genética , Mal de Altura/genética , Altitud , Hipoxia/genética , Mal de Altura/fisiopatología , Estudios de Cohortes , Etiopía , Hipoxia/fisiopatología , Nepal , PerúRESUMEN
OBJECTIVE: To provide age- and sex-specific estimates of methylphenidate use and to determine use changes over a 2-year period. STUDY DESIGN: We examined the first and second data collection cycles of the National Longitudinal Survey of Children and Youth, a Canadian household survey of children. Participants were children aged 2 years to 11 years at both the first and second cycles whose mothers responded; thus, 16,798 (13,059) children were assessed for the first (second) cycle. Logit modeling was used to estimate prevalence of methylphenidate use, to determine sex and age effects on prevalence, and to examine use changes from cycle 1 to 2. RESULTS: Methylphenidate prevalence ranged from 0.09% to 3.89% across 2- to 11-year old children from the first cycle. Boys were 4.6 times more likely than girls to consume methylphenidate. Use was >4 times greater among 6- to 7-year-old children compared with 4- to 5-year-old children and almost 2 times greater among 8- to 9-year-old children compared with 6- to 7-year-old children. Methylphenidate prevalence increased by 36% from cycle 1 to 2. CONCLUSIONS: Methylphenidate prevalence was relatively low. Boys and school-age children had higher rates of methylphenidate use, and use among 2- to 11-year-old children appeared to be increasing over time.