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1.
Clin Genet ; 91(3): 403-410, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27363342

RESUMO

Inherited muscular disorders (IMDs) are clinically and genetically heterogeneous genetic disorders. We investigated the mutational spectrum and genotype-phenotype correlations in Korean patients with IMD. We developed a targeted panel of 69 known IMD genes and recruited a total of 209 Korean patients with IMD. Targeted capture sequencing identified 994 different variants. Among them, 98 variants were classified as pathogenic/likely pathogenic variants; 38 were novel variations. A total of 39 patients had the pathogenic/likely pathogenic variants. Among them, 75 (36%) patients were genetically confirmed, and 18 (9%) patients had one heterozygous variant of recessive myopathy. However, two genetically confirmed patients had an additional heterozygous variant of another recessive myopathy. Four patients with one heterozygous variant of a recessive myopathy showed different phenotypes, compared with the known phenotype of the identified gene. The major causative genes of Korean patients with IMDs were DMD (19 patients), COL6A1 (9), DYSF (9), GNE (7), LMNA (7), CAPN3 (6), and RYR1 (5). This study showed the mutational and clinical spectra in Korean patients with IMD and confirmed the usefulness of strategies utilizing targeted sequencing.


Assuntos
Heterogeneidade Genética , Sequenciamento de Nucleotídeos em Larga Escala , Doenças Musculares/genética , Adulto , Feminino , Estudos de Associação Genética , Humanos , Masculino , Doenças Musculares/fisiopatologia , Mutação , Linhagem , República da Coreia
2.
Phys Chem Chem Phys ; 16(13): 5927-32, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24569648

RESUMO

A major, unprecedented improvement in the durability of polymer electrolyte membrane fuel cells is obtained by tuning the properties of the interface between the catalyst and the ionomer by choosing the appropriate dispersing medium. While a fuel cell cathode prepared from aqueous dispersion showed 90 mV loss at 0.8 A cm(-2) after 30,000 potential cycles (0.6-1.0 V), a fuel cell cathode prepared from glycerol dispersion exhibited only 20 mV loss after 70,000 cycles. This minimum performance loss occurs even though there was an over 80% reduction of electrochemical surface area of the Pt catalyst. These findings indicate that a proper understanding and control of the catalyst-water-ionomer (three-phase) interfaces is even more important for maintaining fuel cell durability in typical electrodes than catalyst agglomeration, and this opens up a novel path for tailoring the functional properties of electrified interfaces.

3.
Environ Int ; 186: 108587, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38579450

RESUMO

Air pollution is a key global environmental problem raising human health concern. It is essential to comprehensively assess the long-term characteristics of air pollution and the resultant health impacts. We first assessed the global trends of fine particulate matter (PM2.5) during 1980-2020 using a monthly global PM2.5 reanalysis dataset, and evaluated their association with three types of climate variability including El Niño-Southern Oscillation, Indian Ocean Dipole and North Atlantic Oscillation. We then estimated PM2.5-attributable premature deaths using integrated exposure-response functions. Results show a significant increasing trend of ambient PM2.5 during 1980-2020 due to increases in anthropogenic emissions. Ambient PM2.5 caused a total of âˆ¼ 135 million premature deaths globally during the four decades. Occurrence of air pollution episodes was strongly associated with climate variability, which were associated with up to 14 % increase in annual global PM2.5-attributable premature deaths.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Saúde Global , Material Particulado , Material Particulado/análise , Poluição do Ar/estatística & dados numéricos , Humanos , Poluentes Atmosféricos/análise , Mudança Climática , Exposição Ambiental/estatística & dados numéricos , Clima , Mortalidade Prematura
4.
Artigo em Inglês | MEDLINE | ID: mdl-37339532

RESUMO

Given the potential for long-term inhibition of bone remodeling/healing and detrimental effects to horses in training, bisphosphonates are tightly regulated in horseracing. Hair has proven to be an effective matrix for detection of drug administration to horses and has been particularly effective in detecting drugs for a long period of time post administration. Thus, hair may prove to be a useful matrix for detection of administration of this class of drugs. The objective of the current study was to develop an assay and assess the usefulness of hair as a matrix for long-term detection of clodronate to horses. Seven horses received a single intramuscular administration of 1.8 mg/kg clodronate. Hair samples were collected prior to and up to 6 months post administration. A liquid chromatography-tandem mass spectrometry method was developed and concentrations of clodronate measured in hair samples. The drug was first detected on day 7 in 4/7 horses, and on days 14, 28 and 35 in the remaining three horses. In 4/7 horses, clodronate was still detectable 6 months post administration. Results of this study demonstrate that, although there was significant inter-individual variability in detection times (63 to 180 days) and several intermediate times where the drug could not be detected but was subsequently detected in later timepoints, clodronate administration was detectable in hair for a prolonged period in most of the horses (4/7) studied.


Assuntos
Ácido Clodrônico , Espectrometria de Massas em Tandem , Cavalos , Animais , Ácido Clodrônico/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Difosfonatos/análise , Cabelo/química
5.
Sci Total Environ ; 880: 163188, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37001679

RESUMO

The outer circulation of tropical cyclones (TCs) on the western North Pacific has been reported to substantially influence the atmospheric environment over the Guangdong-Hong Kong-Macau Greater Bay Area (GBA) of China, whereas dynamic evolution and redistribution of water vapor and aerosol in the atmospheric boundary layer (ABL) responding to moving TCs have yet to be understood. This study aims to answer three key research questions related to the influences of the approaching TCs: (1) how do water vapor and aerosol particles over the GBA change during the TC approaching stage? (2) how does the ABL in terms of vertical wind structure respond to the approaching TCs? and (3) how does turbulence influence the vertical profile of aerosol during the approaching stage? Based on an intensive analysis of three-year reanalysis and Doppler LiDAR data, this study identified a dry-polluted time over the GBA when a TC was located at ~1000 km away on South China Sea. Before that, horizontal wind has consistently come from the northeast, creating a favorable condition for weak transboundary air pollution to the GBA. During the dry-polluted time, the highest surface PM2.5 concentration was resulted from the enhanced downdraft and early-stage wind shear, i.e., stronger wind started occurring at upper-level ABL, while the further turbulent mixing induced by wind shear enhancement and updrafts recovery pumped surface pollution upward to the upper level when TCs became closer. Our findings are expected to improve both weather and PM2.5 forecasts under the impacts of approaching TCs.

6.
Int J Cancer ; 130(5): 1036-45, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21400511

RESUMO

MicroRNAs (miRNAs) regulate mRNA stability and protein expression, and certain miRNAs have been demonstrated to act either as oncogenes or tumor suppressors. Differential miRNA expression signatures have been documented in many human cancers but the role of miRNAs in endometrioid endometrial cancer (EEC) remains poorly understood. This study identifies significantly dysregulated miRNAs of EEC cells, and characterizes their impact on the malignant phenotype. We studied the expression of 365 human miRNAs using Taqman low density arrays in EECs and normal endometriums. Candidate differentially expressed miRNAs were validated by quantitative real-time PCR. Expression of highly dysregulated miRNAs was examined in vitro through the effect of anti-/pre-miRNA transfection on the malignant phenotype. We identified 16 significantly dysregulated miRNAs in EEC and 7 of these are novel findings with respect to EEC. Antagonizing the function of miR-7, miR-194 and miR-449b, or overexpressing miR-204, repressed migration, invasion and extracellular matrix-adhesion in HEC1A endometrial cancer cells. FOXC1 was determined as a target gene of miR-204, and two binding sites in the 3'-untranslated region were validated by dual luciferase reporter assay. FOXC1 expression was inversely related to miR-204 expression in EEC. Functional analysis revealed the involvement of FOXC1 in migration and invasion of HEC1A cells. Our results present dysfunctional miRNAs in endometrial cancer and identify a crucial role for miR-204-FOXC1 interaction in endometrial cancer progression. This miRNA signature offers a potential biomarker for predicting EEC outcomes, and targeting of these cancer progression- and metastasis-related miRNAs offers a novel potential therapeutic strategy for the disease.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , Invasividade Neoplásica , Regiões 3' não Traduzidas , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Neoplasias do Endométrio , Endométrio/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Transfecção , Estudos de Validação como Assunto
7.
Hong Kong Med J ; 18(4): 338-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22865180

RESUMO

Sclerosing stromal tumour of the ovary is rare. Patients present with menstrual irregularities, pelvic pain, abdominal distension, and presence of a large pelvic mass during their twenties or thirties. We report a rare case of an ovarian sclerosing stromal tumour with an atypical presentation, in that it gave rise to recurrent postmenopausal bleeding.


Assuntos
Histerectomia , Neoplasias Ovarianas/complicações , Hemorragia Uterina/cirurgia , Feminino , História do Século XVII , Humanos , Neoplasias Ovarianas/patologia , Pós-Menopausa , Recidiva , Esclerose , Hemorragia Uterina/etiologia
8.
Int J Immunogenet ; 38(2): 145-50, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21176116

RESUMO

Atopic dermatitis (AD) is a chronic pruritic skin condition affecting as much as 15% of children in industrialized countries. While the underlying pathophysiology of AD is not entirely understood, several studies have suggested that AD may mediated by oxidative stress. Glutathione S-transferases (GSTs) are a class of polymorphic enzymes that function to protect against oxidative stress. To identify any possible associations between GSTs polymorphisms and AD susceptibility, the prevalence of two specific polymorphisms -GSTM1 and GSTT1 (homozygous deletion vs. undeleted) - were quantified by multiplex PCR in 145 patients with AD and 267 healthy controls. In individuals with AD, GSTM1/GSTT1 polymorphisms were compared with family history of AD, age of disease onset, disease severity [per SCORing Atopic Dermatitis (SCORAD)], serum IgE level and presence of other allergic diseases. While the GSTM1-null genotype was found to be significantly associated with AD (P = 0.033, OR = 1.579, 95% CI = 1.037-2.403), the correlation between the GSTT1-null genotype and AD did not reach statistical significance (P = 0.577, OR = 1.125, 95% CI = 0.744-1.702). The GSTM1-null genotype was also found to be significantly associated with a childhood onset of AD, the absence of other allergic diseases, and a family history of AD. In combination, these results suggest that GSTM1 is associated with AD susceptibility in Korean subjects.


Assuntos
Povo Asiático/genética , Dermatite Atópica/enzimologia , Dermatite Atópica/genética , Predisposição Genética para Doença , Glutationa Transferase/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Idade de Início , Estudos de Casos e Controles , Dermatite Atópica/epidemiologia , Dermatite Atópica/imunologia , Feminino , Frequência do Gene/genética , Genética Populacional , Humanos , Imunoglobulina E/imunologia , Masculino , República da Coreia/epidemiologia , Índice de Gravidade de Doença , Adulto Jovem
9.
Gynecol Obstet Invest ; 72(3): 203-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21860208

RESUMO

BACKGROUND: The CHD5 gene located on 1p36 encodes a protein-chromodomain helicase DNA-binding protein 5. CHD5 has been shown to be a tumor suppressor gene candidate. This study investigated the involvement of CHD5 in ovarian cancer and its clinicopathological significance. METHODS: CHD5 expression in ovarian cancer and its counterpart were determined by quantitative RT-PCR. The correlation of CHD5 expression to clinicopathological features of the tumor was analyzed. RESULTS: CHD5 expression was downregulated by at least twofold in 32 of 72 (41%) invasive epithelial ovarian carcinomas when compared to 12 controls in Hong Kong Chinese women. CHD5 downregulation was correlated to clinical status (p < 0.05), but not to patient age, tumor type and grade, recurrence and clinical stage (p > 0.05). Survival analysis showed that patients with CHD5 downregulation in their tumors were associated with shorter disease-free and total survival times compared to those without CHD5 downregulation (p < 0.05). Cox proportional-hazards regression analysis indicated that downregulation of CHD5 is an independent adverse prognostic factor in ovarian cancer. CONCLUSION: This study shows that CHD5 is downregulated in a certain number of ovarian cancers and appears to be an adverse predictor candidate of ovarian cancer disease-free and total survival.


Assuntos
DNA Helicases/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Epiteliais e Glandulares/genética , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/genética , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida
10.
Scand J Rheumatol ; 39(3): 190-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20141484

RESUMO

OBJECTIVE: The interleukin (IL)-1 family and its related family members are primary inflammatory cytokines. The aim of this study was to assess the possible association between nine IL-1 family gene polymorphisms and rheumatoid arthritis (RA). METHODS: To investigate the genetic association between IL-1 family gene polymorphisms and the risk of RA in a Korean population, 69 single nucleotide polymorphisms (SNPs) of the nine IL-1 family gene regions were selected. A total of 806 subjects (498 controls and 308 RA patients) were included in the study. The genotypes of the selected SNPs in the IL-1 family genes were determined using Illumina Sentrix Array Matrix chips. SNP Stats, Haploview, and SNP Analyzer, and Helixtree programs were used for the analysis of the genetic data. RESULTS: We observed statistically significant associations between the SNPs of IL1F10 and IL1RN among the IL-1 family genes in the RA patients and the control population. When the patients were divided into two groups according to the parameters of disease activity, including C-reactive protein (CRP) level (> or = 0.5 or < 0.5 mg/dL), the erythrocyte sedimentation rate (ESR) (> or = 30 or < 30 mm/h), and parameters of severity, including rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), and bone erosion (positive or not), we found significant associations between the parameters, including CRP, ESR, and bone erosion, and SNPs of the IL-1 family genes in RA. CONCLUSION: This study suggests that IL-1 family gene (IL1F10 and IL1RN) polymorphisms may play an important role in the susceptibility to developing RA.


Assuntos
Artrite Reumatoide/genética , Povo Asiático/genética , Interleucina-1/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Alelos , Sedimentação Sanguínea , Proteína C-Reativa , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Análise de Regressão , República da Coreia
11.
Int J Immunogenet ; 37(4): 289-91, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20518838

RESUMO

The precise cause of vitiligo is unknown. However, autoimmunity is considered the most likely aetiology, especially in nonsegmental vitiligo (NSV). In this study we determined whether or not the transforming growth factor beta receptor II (TGFBR2) gene contributes to susceptibility for NSV in the Korean population. Blood samples were collected from 415 controls and 233 cases. We selected three single nucleotide polymorphisms (SNPs) in the TGFBR2 gene. The genotypes of the SNPs were determined using direct sequencing. All of the SNPs were significantly different between the vitiligo patients and controls (rs2005061, co-dominant, dominant, recessive, P < 0.05; rs3773645, co-dominant, dominant, recessive, P < 0.05; rs3773649, co-dominant, recessive, P < 0.05). In addition, haplotype 1 (CG) and haplotype 2 (GA) of the linkage disequilibrium (LD) block were also associated with a risk of NSV. The present study suggests that TGFBR2 might be related to NSV.


Assuntos
Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Vitiligo/genética , Adulto , Doenças Autoimunes/epidemiologia , Doenças Autoimunes/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Receptor do Fator de Crescimento Transformador beta Tipo II , República da Coreia/epidemiologia , Vitiligo/epidemiologia , Vitiligo/imunologia , Adulto Jovem
12.
Mycoses ; 53(6): 522-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19558428

RESUMO

Fluconazole, which is a drug of the azole family, is safely used in systemic treatment of oral and intravenous injection, but it is difficult to use fluconazole as a topical application because of its large molecular weight and strong hydrophilic property. This study is a multicentre, double-blind, randomised, non-inferiority study to compare the antifungal effect and safety of fluconazole cream 0.5% and 1% with flutrimazole cream 1% in superficial mycosis. A total of 162 subjects selected to participate in this study were equally divided into three groups and assigned to be given fluconazole cream 0.5%, fluconazole cream 1%, and flutrimazole cream 1% in the ratio of 1 : 1. The primary index of drug efficacy was determined by complete mycological cure in which no fungus was detected on KOH smear test 4 weeks after application of fluconazole. The secondary index of efficacy was defined as complete mycological cure 4 weeks after the application of fluconazole, improvement of clinical symptoms and overall effectiveness assessed by the research staff. According to this study, on comparing the efficacy of cure of superficial dermatomycosis after 4 weeks of application, both fluconazole 0.5% and fluconazole 1% cream were found to be equally effective and non-inferior to flutrimazole 1% cream. Given the effectiveness and safety of the drug, both fluconazole 0.5% and 1% cream might be said to be optimal concentration in the treatment of superficial dermatomycosis.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Clotrimazol/análogos & derivados , Dermatomicoses/tratamento farmacológico , Fluconazol/administração & dosagem , Fluconazol/efeitos adversos , Administração Tópica , Adulto , Arthrodermataceae/isolamento & purificação , Clotrimazol/administração & dosagem , Clotrimazol/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/microbiologia , Resultado do Tratamento
13.
Chemosphere ; 230: 578-586, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31125886

RESUMO

The physical, chemical and bioreactivity characteristics of fine particulate matter (PM2.5) collected near (<1 km) two landfill sites and downwind urban sites were investigated. The PM2.5 concentrations were significantly higher in winter than summer. Diurnal variations of PM2.5 were recorded at both landfill sites. Soot aggregate particles were identified near the landfill sites, which indicated that combustion pollution due to landfill activities was a significant source. High correlation coefficients (r) implied several inorganic elements and water-soluble inorganic ions (vanadium (V), copper (Cu), chloride (Cl-), nitrate (NO3-), sodium (Na) and potassium (K)) were positively associated with wind flow from the landfill sites. Nevertheless, no significant correlations were also identified between these components against DNA damage. Significant associations were observed between DNA damage and some heavy metals such as cadmium (Cd) and lead (Pb), and total Polycyclic Aromatic Hydrocarbons (PAHs) during the summer. The insignificant associations of DNA damage under increased wind frequency from landfills suggested that the PM2.5 loading from sources such as regional sources was possibly an important contributing factor for DNA damage. This outcome warrants the further development of effective and source-specific landfill management regulations for particulate matter production control to the city.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/análise , Instalações de Eliminação de Resíduos , Poluentes Atmosféricos/toxicidade , Cidades , Dano ao DNA , Hong Kong , Metais Pesados/análise , Metais Pesados/toxicidade , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Estações do Ano , Vento
14.
Oncogene ; 26(13): 1971-82, 2007 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-17043662

RESUMO

Endometrial cancer is the third most common gynecologic malignancy and the ninth most common malignancy for females overall in Hong Kong. Approximately 80% or more of these cancers are endometrioid endometrial adenocarcinomas. The aim of this study was to reveal genes contributing to the development of endometrioid endometrial cancer, which may impact diagnosis, prognosis and treatment of the disease. Whole-genome gene expression analysis was completed for a set of 55 microdissected sporadic endometrioid endometrial adenocarcinomas and 29 microdissected normal endometrium specimens using the Affymetrix Human U133 Plus 2.0 oligonucleotide microarray. Selected genes of interest were validated by quantitative real-time-polymerase chain reaction (qRT-PCR). Pathway analysis was performed to reveal gene interactions involved in endometrial tumorigenesis. Unsupervised hierarchical clustering displayed a distinct separation between the endometrioid adenocarcinomas and normal endometrium samples. Supervised analysis identified 117 highly differentially regulated genes (>or=4.0-fold change), which distinguished the endometrial cancer specimens from normal endometrium. Twelve novel genes including DKK4, ZIC1, KIF1A, SAA2, LOC16378, ALPP2, CCL20, CXCL5, BST2, OLFM1, KLRC1 and MBC45780 were deregulated in the endometrial cancer, and further validated in an independent set of 56 cancer and 29 normal samples using qRT-PCR. In addition, 10 genes were differentially regulated in late-stage cancer, as compared to early-stage disease, and may be involved in tumor progression. Pathway analysis of the expression data from this tumor revealed an interconnected network consisting of 21 aberrantly regulated genes involved in angiogenesis, cell proliferation and chromosomal instability. The results of this study highlight the molecular features of endometrioid endometrial cancer and provide insight into the events underlying the development and progression of endometrioid endometrial cancer.


Assuntos
Neoplasias do Endométrio/metabolismo , Perfilação da Expressão Gênica , Genoma , Transdução de Sinais , Neoplasias do Endométrio/genética , Feminino , Hong Kong , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Bioresour Technol ; 99(1): 1-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17306978

RESUMO

In order to obtain basic design criteria for anaerobic digesters of swine manure, the effects of different digesting temperatures, temperature shocks and feed loads, on the biogas yields and methane content were evaluated. The digester temperatures were set at 25, 30 and 35 degrees C, with four feed loads of 5%, 10%, 20% and 40% (feed volume/digester volume). At a temperature of 30 degrees C, the methane yield was reduced by only 3% compared to 35 degrees C, while a 17.4% reduction was observed when the digestion was performed at 25 degrees C. Ultimate methane yields of 327, 389 and 403 mL CH(4)/g VS(added) were obtained at 25, 30 and 35 degrees C, respectively; with moderate feed loads from 5% to 20% (V/V). From the elemental analysis of swine manure, the theoretical biogas and methane yields at standard temperature and pressure were 1.12L biogas/g VS(destroyed) and 0.724 L CH(4)/g VS(destroyed), respectively. Also, the methane content increased with increasing digestion temperatures, but only to a small degree. Temperature shocks from 35 to 30 degrees C and again from 30 to 32 degrees C led to a decrease in the biogas production rate, but it rapidly resumed the value of the control reactor. In addition, no lasting damage was observed for the digestion performance, once it had recovered.


Assuntos
Esterco/microbiologia , Metano/biossíntese , Eliminação de Resíduos/métodos , Animais , Bactérias Anaeróbias/metabolismo , Biodegradação Ambiental , Reatores Biológicos , Desenho de Equipamento , Suínos , Temperatura
16.
Environ Technol ; 29(1): 91-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18610549

RESUMO

The major objective of this study was to delineate the effect of nitrate on the UV oxidation of benzene and toluene, dissolved in less than 100 microg l(-1), by conducting a bench-scale operation at various reaction times and with various initial concentrations of H2O2 and NO3-. The oxidation of benzene and toluene can be expected to be only about 10% and 18%, respectively, through the photolysis of H2O2 (initial conc. of 50 mg l(-1)), where the reactor was operated at a reaction time of 2 min, with an initial NO(3-)-N concentration of 5 mg l(-1). Nitrate clearly hindered UV oxidation when the initial H2O2 concentration in the reactor was less than 50 mg l(-1). Even if approximately 40% removal could be achieved under the conditions mentioned above (an initial H2O2 concentration of 200 mg l(-1) at a reaction time of 9 min, with a high UV dose), the operating conditions for the 40% removal might be beyond the practical limits applied for effluents discharged from wastewater treatment plants. The results of the experiment also indicate that benzene and toluene can be oxidized in very limited amounts through direct photolysis, without additional oxidation by hydroxyl radicals.


Assuntos
Benzeno/química , Peróxido de Hidrogênio/química , Nitratos/química , Fotólise , Tolueno/química , Oxirredução , Raios Ultravioleta , Eliminação de Resíduos Líquidos
17.
Rev Sci Instrum ; 89(11): 116102, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30501340

RESUMO

We designed a double-layered polyimide film heater where the direction of the injection current of each layer is opposite to that of the other layer to reduce the magnetic field. The width of the heater is 0.125 mm and the resistance is 21.2 Ω. This specially designed heater successfully demonstrated temperature controllability within 10 mK for an atomic cell in an atom spin gyroscope while minimizing the generation of the magnetic field to within 1 nT.

18.
Curr Top Microbiol Immunol ; 306: 153-82, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16909921

RESUMO

The airway provides numerous defense mechanisms to prevent microbial colonization by the large numbers of bacteria and viruses present in ambient air. An important component of this defense is the antimicrobial peptides and proteins present in the airway surface fluid (ASF), the mucin-rich fluid covering the respiratory epithelium. These include larger proteins such as lysozyme and lactoferrin, as well as the cationic defensin and cathelicidin peptides. While some of these peptides, such as human beta-defensin (hBD)-1, are present constitutively, others, including hBD2 and -3 are inducible in response to bacterial recognition by Toll-like receptor-mediated pathways. These peptides can act as microbicides in the ASF, but also exhibit other activities, including potent chemotactic activity for cells of the innate and adaptive immune systems, suggesting they play a complex role in the host defense of the airway. Inhibition of antimicrobial peptide activity or gene expression can result in increased susceptibility to infections. This has been observed with cystic fibrosis (CF), where the CF phenotype leads to reduced antimicrobial capacity of peptides in the airway. Pathogenic virulence factors can inhibit defensin gene expression, as can environmental factors such as air pollution. Such an interference can result in infections by airway-specific pathogens including Bordetella bronchiseptica, Mycobacterium tuberculosis, and influenza virus. Research into the modulation of peptide gene expression in animal models, as well as the optimization of peptide-based therapeutics shows promise for the treatment and prevention of airway infectious diseases.


Assuntos
Peptídeos Catiônicos Antimicrobianos/fisiologia , Defensinas/fisiologia , Sistema Respiratório/imunologia , Animais , Fibrose Cística/imunologia , Modelos Animais de Doenças , Humanos , Lactoferrina/fisiologia , Muramidase/fisiologia , Proteínas Secretadas Inibidoras de Proteinases , Proteínas/fisiologia , Receptores Toll-Like/fisiologia , Tuberculose Pulmonar/imunologia , Viroses/imunologia , Catelicidinas
19.
Mol Cell Biol ; 11(7): 3573-83, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1675427

RESUMO

We used a series of cell clones from a human teratocarcinoma cell line, PA-1, to study the effect of transformation by an activated N-ras oncogene on the expression of genes involved in retinoic acid (RA)-induced differentiation and growth regulation. Recently, it has been shown that expression of human HOX 2 genes is sequentially activated by RA beginning from Hox 2.9 at the 3' end of the HOX 2 cluster (A. Simeone, D. Acampora, L. Arcioni, P. W. Andrews, E. Boncinelli, and F. Mavilio, Nature [London] 346:763-766, 1990). We now report that six different genes of the cluster HOX 1 are sequentially induced by RA in a similar temporal pattern, beginning with genes at the 3' end of the cluster. However, in N-ras-transformed cell clones, RA-induced expression of these homeobox genes is delayed. Hox 1.4 and Hox 1.3, genes abundantly induced in nontransformed clones after 3 days of RA treatment, are expressed in N-ras-transformed cells only after 10 days of RA treatment. At this time, the cells' growth is arrested at very high density, and no differentiated morphologic characteristics are observed. Constitutive expression of a transfected Hox 1.4 gene under the control of a simian virus 40 promotor leads to differentiated cell morphology similar to that of the RA-induced phenotype and restores the growth-inhibitory effects of RA in N-ras-transformed cells. These observations provide evidence that enhanced proliferation in N-ras-transformed cells compromises teratocarcinoma cell differentiation by a mechanism that transiently suppresses homeobox gene induction and implies a central role for homeobox genes in RA-induced cell differentiation. We conclude that stimulation of a putative growth factor signal pathway, associated with ras-induced proliferation, transiently suppresses the induction of transcription factors functionally involved in cell growth and differentiation.


Assuntos
Transformação Celular Neoplásica , Regulação Neoplásica da Expressão Gênica , Genes Homeobox , Genes ras , Sequência de Aminoácidos , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Clonagem Molecular , DNA Recombinante/isolamento & purificação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Família Multigênica , Sondas de Oligonucleotídeos , Reação em Cadeia da Polimerase , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Teratoma , Ativação Transcricional , Transfecção , Tretinoína/farmacologia
20.
Mol Cell Biol ; 13(7): 4174-85, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8321221

RESUMO

AP-2 is a retinoic acid-inducible and developmentally regulated activator of transcription. We have cloned an alternative AP-2 transcript (AP-2B) from the human teratocarcinoma cell line PA-1, which encodes a protein differing in the C terminus from the previously isolated AP-2 protein (AP-2A). This protein contains the activation domain of AP-2 and part of the DNA binding domain but lacks the dimerization domain which is necessary for DNA binding. Analysis of overlapping genomic clones spanning the entire AP-2 gene proves that AP-2A and AP-2B transcripts are alternatively spliced from the same gene. Both transient and stable transfection experiments show that AP-2B inhibits AP-2 transactivator function, as measured by an AP-2-responsive chloramphenicol acetyltransferase reporter plasmid. Furthermore, constitutive AP-2B expression in PA-1 cells causes a retinoic acid-resistant phenotype, anchorage-independent growth in soft agar, and tumorigenicity in nude mice, in a fashion similar to transformation of these cells by oncogenes. To determine the mechanism by which AP-2B exerts its inhibitory function, we purified bacterially expressed AP-2A and AP-2B proteins. While bacterial AP-2B does not bind an AP-2 consensus site, it strongly inhibits binding of the endogenous AP-2 present in PA-1 cell nuclear extracts. However, DNA sequence-specific binding of bacterially expressed AP-2A cannot be inhibited by bacterially expressed AP-2B. Therefore, inhibition of AP-2 activity by the protein AP-2B may require an additional factor or modification supplied by nuclear extracts.


Assuntos
Processamento Alternativo , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética , Transcrição Gênica , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular , Divisão Celular , Clonagem Molecular , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Drosophila , Proteínas de Drosophila , Feminino , Humanos , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Fator de Transcrição AP-2 , Fatores de Transcrição/metabolismo , Ativação Transcricional , Tretinoína/farmacologia , Células Tumorais Cultivadas
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