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1.
Nano Lett ; 19(10): 7119-7123, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31429575

RESUMO

An interface of molecule and metal has attracted much attention in the research field of nanoelectronics because of their high degree of design freedom. Here, we demonstrate an efficient spin-to-charge current conversion at the metal surface covered by a single layer of molecules. Spin currents are injected into an interface between metal (Cu) and lead(II) phthalocyanine by means of the spin pumping method. An observed voltage signal is caused by the inverse Edelstein effect, i.e., spin-to-charge current conversion at the interface. The conversion coefficient, inverse Edelstein length, is estimated to be 0.40 ± 0.06 nm, comparable with the largest Rashba spin splitting of interfaces with heavy metals. Interestingly, the Edelstein length strongly depends on the thickness of the molecule and takes a maximum value when a single layer of molecules is formed on the Cu surface. Comparative analysis between scanning probe microscopy and first-principles calculations reveal that the formation of interface state with Rashba spin splitting causes the inverse Edelstein effect, whose magnitude is sensitive to the adsorption configuration of the molecules.

2.
Sci Total Environ ; 599-600: 431-441, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482301

RESUMO

To investigate the effects of unequal supply hours on consumers' coping strategies and perceptions of the intermittent water supply (IWS) in the Kathmandu Valley (KV), Nepal we conducted a randomized household survey (n=369) and on-site water quality tests. Half of the households received piped water for 6 or fewer hours per week. To augment or cope with the inadequate supply, 28% of the households used highly contaminated and expensive tanker-delivered water. Half of the piped water samples (n=13) were contaminated with Escherichia coli. Free chlorine concentration in all piped water samples was below the national standards (0.1-0.2mg/L), but combined chlorine was detected at an average of 0.24mg/L, indicating ingression of contaminants in the network. Point-of-use devices could increase access to safe water in the KV from 42% to 80%. The use of Lorenz curves and Gini coefficients revealed inequality of piped water supply hours per week both between and within service areas in the KV, due mainly to a small percentage of households who receive longer supply hours. To cope with reduced supply hours, home owners pay more to get water from alternative sources, while tenants compromise their water consumption. Under IWS, expectations for improvements in piped water quality and supply regularity are higher than those for supply volume. Consumers' perceptions of the piped water services worsen with the reduction in supply hours, but perceptions of piped water tariff are independent of supply hours.

3.
Org Biomol Chem ; 14(30): 7191-6, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27404292

RESUMO

Catalyst-dependent divergent pathways of 2-naphthol derivatives have been investigated. A readily available CuCl2-DMAP catalyst system promotes the aerobic oxidation of 2-naphthol derivatives to ortho-naphthoquinones whereas switching the catalyst system to Cu(OAc)2-DBN under an argon atmosphere allows the oxidative coupling of 2-naphthols to 1,1'-bi-2-naphthols (BINOLs) in good to excellent yields.

4.
Environ Pollut ; 205: 131-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26057475

RESUMO

We evaluated factors affecting the transport, retention, and re-entrainment of carbon black nanoparticles (nCBs) in two saturated natural soils under different flow conditions and input concentrations using the two-site transport model and Kelvin probe force microscopy (KPFM). Soil organic matter (SOM) was found to create unfavorable conditions for the retention. Despite an increased flow velocity, the relative stability of the estimated maximum retention capacity in soils may suggest that flow-induced shear stress forces were insufficient to detach nCB. The KPFM observation revealed that nCBs were retained at the grain boundary and on surface roughness, which brought about substantial discrepancy between theoretically-derived attachment efficiency factors and the ones obtained by the experiments using the two-site transport model. Thus, decreasing ionic strength and increasing solution pH caused re-entrainment of only a small fraction of retained nCB in the soil columns.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Solo/química , Fuligem/química , Adsorção , Recuperação e Remediação Ambiental/instrumentação , Nanopartículas/química , Poluentes do Solo/isolamento & purificação
5.
Water Sci Technol ; 66(6): 1348-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22828316

RESUMO

Dissolved organic matter (DOM) and phosphate in reclaimed water promote microbial growth in distribution systems and deteriorate water quality. In this study, we tested ferrihydrite (Fh) for its potential to remove both DOM and phosphate in order to control bacterial regrowth. Adsorption kinetics on Fh revealed that phosphate has a higher affinity with Fh than has DOM. The removal efficiency of DOM increased at lower pH. Fourier transform infrared spectroscopy (FT-IR) spectra of freeze-dried Fh showed that adsorbed DOM was rich in carboxyl/hydroxyl functional groups, indicating anion exchange at Fh surfaces to be a major mechanism, especially at low pH. Fh preferentially removed DOM greater than 1,000 Da. Specific ultraviolet absorption (SUVA) at 254 nm and DOC results suggest Fh adsorption removes more hydrophilic DOM than the coagulation-sand filtration process. Reduction of bacterial regrowth potential (BRP) by Fh was comparable to that of the coagulation-sand filtration process, which indicated that phosphorus was not the rate-limiting factor of microbial growth.


Assuntos
Bactérias/crescimento & desenvolvimento , Compostos Férricos/química , Fosfatos/química , Microbiologia da Água , Purificação da Água , Fatores de Tempo
6.
Water Sci Technol ; 61(9): 2391-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20418637

RESUMO

Groundwater is the major source of drinking water in Lamphun Province in the Chiang Mai Basin, Thailand. However, groundwater contains high fluoride up to 16 mg F/L, which has caused dental and skeletal fluorosis. Although Thai Government installed RO membrane plants for the removal of fluoride from groundwater; and delivers RO-filtered bottled water that contains less fluoride than the Thai Standard of 0.7 mg F/L, it was found that the urinary fluoride levels are still high among the residents. To find the major sources of fluoride intake, fluoride contents in various water sources, such as village water supply, shallow and deep groundwaters, rain water and bottled water, were measured, and the local people's behavior on water uses was recorded by interview and questionnaire study. As a result, it was found that the highest risk of fluoride ingestion comes from cooking rice with fluoride-containing water because of a lack of knowledge on fluoride sources and fluoride chemistry. To reduce the health risks arising from fluoride intake, a hands-on educational program on the sources and risks of fluoride in water was developed and implemented in the local schools. The participatory educational program promoted active involvement of schoolchildren, but it was found that the effectiveness of education varied depending on the questions we asked. Therefore, it needs to be improved by an iterative and interactive educational program. In conclusion, it was found that the benefits of providing safe drinking water using such advanced technology as RO membrane can be maximized only when it comes along with a participatory educational program on fluoride sources and health risks.


Assuntos
Exposição Ambiental , Fluoretos/química , Fluoretos/toxicidade , Fluorose Dentária/epidemiologia , Abastecimento de Água/análise , Criança , Culinária , Coleta de Dados , Ingestão de Líquidos , Fluoretos/metabolismo , Fluorose Dentária/prevenção & controle , Humanos , Oryza/metabolismo , Fatores de Risco , Instituições Acadêmicas , Inquéritos e Questionários , Tailândia , Água/química
7.
Kidney Int ; 72(12): 1512-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17898696

RESUMO

Hyperinsulinemia has been implicated in the development of diabetic nephropathy. In the present study we compared the renoprotective effects of the thiazolidinedione, pioglitazone (PGZ), to that of insulin in a hypertensive, obese, type II diabetic rat model. PGZ aggravated obesity and gave less glycemic control than insulin. However, renoprotection was markedly better with PZG compared to insulin as shown by lower proteinuria, improved renal function, and less histological evidence of diabetic glomerular and tubulointerstitial lesions. PZG and insulin both reduced renal accumulation of pentosidine and oxidative stress to a similar extent. In contrast, PGZ but not insulin suppressed enhanced transforming growth factor-beta (TGF-beta) expression. We further confirmed in cultured rat proximal tubular cells that insulin enhanced TGF-beta mRNA expression and protein production. Our results identify hyperinsulinemia and the attendant increase of TGF-beta expression as potential therapeutic targets in diabetes independent of glycemic control. This confirms prior clinical evidence that PZG provides renoprotection in obese, diabetic patients with nephropathy.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Tiazolidinedionas/farmacologia , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Modelos Animais de Doenças , Produtos Finais de Glicação Avançada/metabolismo , Hiperinsulinismo/complicações , Hipertensão Renal/complicações , Rim/efeitos dos fármacos , Masculino , Obesidade/complicações , Estresse Oxidativo/efeitos dos fármacos , Pioglitazona , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo , Proteinúria/prevenção & controle , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Fator de Crescimento Transformador beta/sangue , Fator de Crescimento Transformador beta/genética
8.
J Child Neurol ; 22(1): 60-6, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17608307

RESUMO

This report describes a male patient who presented with symptoms suggestive of spinocerebellar degeneration and who died of respiratory failure at the age of 7 years but was diagnosed, at autopsy, as having neuronal intranuclear hyaline inclusion disease. Neuronal intranuclear hyaline inclusion disease is a progressive and degenerative disease; diagnosis is possible only by neuropathological analysis. This is a rare disorder; few cases with early childhood onset and rapidly progressive neurologic symptoms have been documented. According to previous reports, most neurons in the central nervous system exhibited intranuclear eosinophilic inclusion bodies; neuronal depletion appeared to be restricted to the cerebellar cortex and the medullary inferior olivary nuclei, consistent with the fact that clinical deficit appears to correspond to the site of neuronal depletion and not to where eosinophilic bodies are detected. Immunohistochemical analysis revealed that these inclusions were positive for ubiquitin. The case presented herein clearly indicates that neuronal intranuclear hyaline inclusion disease should be considered as a differential diagnosis of cases involving spinocerebellar degeneration with childhood onset.


Assuntos
Hialina/metabolismo , Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/patologia , Degenerações Espinocerebelares/metabolismo , Criança , Progressão da Doença , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Humanos , Corpos de Inclusão Intranuclear/ultraestrutura , Imageamento por Ressonância Magnética/métodos , Masculino , Microscopia Eletrônica de Transmissão , Degenerações Espinocerebelares/patologia , Degenerações Espinocerebelares/fisiopatologia
9.
Water Sci Technol ; 54(3): 203-10, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17037154

RESUMO

Floodwaters in Kampung Melayu village, Jakarta, Indonesia, as well as river water and consumable water (including groundwater and tap water) samples in flooded and non-flooded areas, were quantitatively analysed to assess occurrence of viruses and total coliforms and E. coli as bacterial indicators after flooding event. High numbers of enterovirus, hepatitis A virus, norovirus (G1, G2) and adenovirus were detected at high concentration in floodwaters and waters sampled from Ciliwung River which runs across metropolitan Jakarta and is used widely for agriculture and domestic purposes by poor residents. One out of three groundwater wells in the flooded area was contaminated with all viruses tested while no viruses were found in groundwater samples in non-flooded areas and tap water samples. The results revealed that human enteric viruses, especially hepatitis A virus and adenovirus, were prevalent in Jakarta, Indonesia. This study suggested that flooding posed a higher risk of viral infection to the people through contamination of drinking water sources or direct contact with floodwaters.


Assuntos
Desastres , Enterobacteriaceae/isolamento & purificação , Enterovirus/isolamento & purificação , Microbiologia da Água , Sequência de Bases , Primers do DNA , Indonésia , Abastecimento de Água
10.
Neuroscience ; 141(4): 1861-9, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16844304

RESUMO

Pelizaeus-Merzbacher disease (PMD) is a rare X-linked leukodystrophy caused by proteolipid protein 1 (PLP1) gene mutations. Previous studies indicated that proteolipid proteins (PLPs) with disease-associated mutations are misfolded and trapped in the endoplasmic reticulum (ER) during transportation to the cell surface, which eventually leads to oligodendrocyte cell death in PMD. Here we report a PMD patient with a very mild phenotype carrying a novel mutation (485G-->T) in exon 4 of the PLP1 gene that causes a Trp(162)Leu substitution in the protein. We also investigated intracellular trafficking of this mutant PLP in COS-7 cells. Transiently transfected mutant PLP(W162L) fused to an enhanced green fluorescent protein (EGFP) or a short peptide tag was not carried to the plasma membrane. However, in contrast to previous studies, this mutant PLP was not retained in the ER, indicating an escape of the newly translated protein from the quality control machinery. We also found that the mutant PLP accumulated in the nuclear envelope (NE) in a time-dependent manner. This mutant PLP, with its distribution outside the ER and a very mild phenotype, supports the idea that accumulation of misfolded mutant protein in the ER causes the severe phenotype of PMD.


Assuntos
Proteínas de Membrana/metabolismo , Proteína Proteolipídica de Mielina/metabolismo , Doença de Pelizaeus-Merzbacher/metabolismo , Animais , Células COS , Pré-Escolar , Chlorocebus aethiops , Clonagem Molecular/métodos , Éxons , Imunofluorescência/métodos , Expressão Gênica/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Leucina/genética , Imageamento por Ressonância Magnética/métodos , Masculino , Proteínas de Membrana/genética , Mutagênese/fisiologia , Mutação/genética , Proteína Proteolipídica de Mielina/genética , Doença de Pelizaeus-Merzbacher/genética , Doença de Pelizaeus-Merzbacher/patologia , Transporte Proteico/fisiologia , Receptores de Peptídeos/metabolismo , Frações Subcelulares/metabolismo , Fatores de Tempo , Transfecção/métodos , Triptofano/genética
11.
Water Sci Technol ; 53(6): 137-43, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16749450

RESUMO

A large amount of alkylphenol polyethoxylate (APnEOs), one of endocrine disrupters, is disposed of directly to biological wastewater treatment plants. But microbial oxidation processes cannot completely degrade these molecules to nontoxic forms. Adsorption and recovery efficiency of APnEOs was investigated using four different types of Hexagonal Mesoporous Silicate (HMSs) and powdered activated carbon (PAC). HMSs were synthesized by surfactant-templating methods, and two of them were subsequently grafted with surface functional groups. The two types of organic functional groups grafted on the surface were n-octyldimethyl- and 3-mercaptopropyl- groups. Titanium substituted HMS was also made in the same way as HMS. Adsorption of APnEOs on synthesized HMSs was higher than that on PAC. Larger pore sizes of HMS and Ti-HMS enhanced accessibility of APnEOs to active surface sites in mesopores, which realized higher adsorption capacities and L-shape (Langmuir) adsorption isotherms. Adsorption capacities of APnEOs are influenced by water solubility of APnEOs. APnEOs adsorbed on HMSs can be completely recovered by a mixture of alcohol and water at 5:5 ratio, which is more effective than the recovery from PAC.


Assuntos
Adsorção , Fenóis/química , Polietilenoglicóis/química , Silicatos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Porosidade , Dióxido de Silício , Solventes/química , Difração de Raios X
12.
Water Sci Technol ; 53(2): 45-52, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16594322

RESUMO

The main objective of this paper is to simulate the effects of soil erosion on river water quality and on agricultural production as a result of the transformation of forestlands in the catchment of the upstream Phong River. Suspended solids carry down attached nutrients and agricultural chemicals causing water pollution in the downstream. There are four different types of land use in this simulation, namely forestlands, flatland and highland sugarcane plantation areas, and paddy fields. The highest mean annual amount of soil erosion is from paddy fields (585,700 tons/year), followed by highland (73,800 tons/year) and flatland (63,950 tons/year) sugarcane plantation areas and forestlands (41,800 tons/year), respectively. However, as most of paddy fields are located in a low land and are wet type cultivations, the soil erosion occurred has less impact on river water quality and its production compared to the soil erosion from the steeper slopes of highland plantation areas. Under the resource-based agriculture, the sugarcane production is mainly increased by expanding the plantation areas leading to a significant loss of topsoil and a considerable reduction of agricultural production. Soil erosion contributes to an increase in the average annual suspended solids concentration by 72 mg/l.


Assuntos
Poluentes Químicos da Água , Agricultura , Conservação dos Recursos Naturais , Ecossistema , Meio Ambiente , Monitoramento Ambiental , Substâncias Perigosas , Chuva , Rios , Solo , Tailândia , Água , Movimentos da Água , Poluentes da Água , Abastecimento de Água
13.
Water Sci Technol ; 51(6-7): 231-40, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16003982

RESUMO

Two pilot-scale powdered activated carbon-microfiltration (PAC-MF) reactors were operated using river water pretreated by a biofilter. A high permeate flux (4 m/d) was maintained in two reactors with different particle sizes of PAC. High concentration (20 g/L) in the PAC adsorption zone demonstrated 60-80% of organic removal rates. Analysis on the PAC cake fouling demonstrated that attached metal ions play more important role than organic matter attached on PAC to the increase of PAC cake resistance. Effects of factors which may cause PAC cake fouling in PAC-MF process were investigated and evaluated by batch experiments, further revealing that small particulates and metal ions in raw water impose prominent influence on the PAC cake layer formation. Fe (II) precipitates after being oxidized to Fe (III) during PAC adsorption and thus Fe(ll) colloids display more significant effect than other metal ions. At a high flux, PAC cake layer demonstrated a higher resistance with larger PAC due to association among colloids, metals and PAC particles, and easy migration of small particles in raw water into the void space in the PAC cake layer. Larger PAC possesses much more non-uniform particle size distribution and larger void space, making it easier for small colloids to migrate into the voids and for metal ions to associate with PAC particles by bridge effect, hence speeding up and intensifying the of PAC cake fouling on membrane surface.


Assuntos
Carbono/química , Coloides/química , Membranas Artificiais , Poluentes da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Falha de Equipamento , Compostos Férricos/química , Compostos Ferrosos/química , Floculação , Metais/química , Compostos Orgânicos/isolamento & purificação , Oxirredução , Tamanho da Partícula , Permeabilidade , Solubilidade , Ultrafiltração
14.
Br J Cancer ; 92(12): 2286-91, 2005 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-15886699

RESUMO

The DNA mismatch repair gene is a key regulator in the elimination of base-base mismatches and insertion/deletion loops (IDLs). Human MutS homologue 2 (hMSH2), originally identified as a human homologue of the bacterial MutS, is a tumour suppressor gene frequently mutated in hereditary non-polyposis colorectal cancer. Hereditary non-polyposis colorectal cancer is characterised by the early onset of colorectal cancer and the development of extracolonic cancers such as endometrial, ovarian, and urological cancers. Oestrogen receptor (ER) alpha and beta are members of a nuclear receptor (NR) superfamily. Ligand-dependent transcription of ER is regulated by the p160 steroid receptor coactivator family, the thyroid hormone receptor-associated proteins/the vitamin D receptor-interacting proteins (TRAP/DRIP) mediator complex, and the TATA box-binding protein (TBP)-free TBP associated factor complex (TFTC) type histone acetyltransferase complex. Here, we report the interaction between ER alpha/beta and hMSH2. Immunoprecipitation and glutathione-S-transferase pull-down assay revealed that ER alpha and hMSH2 interacted in a ligand-dependent manner, whereas ER beta and hMSH2 interacted in a ligand-independent manner. Oestrogen receptor alpha/beta bound to hMSH2 through the hMSH3/hMSH6 interaction domain of hMSH2. In a transient expression assay, hMSH2 potentiated the transactivation function of liganded ER alpha, but not that of ER beta. These results suggest that hMSH2 may play an important role as a putative coactivator in ER alpha dependent gene expression.


Assuntos
Pareamento Incorreto de Bases/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Receptor alfa de Estrogênio/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Mapeamento Cromossômico , Neoplasias do Endométrio/genética , Receptor beta de Estrogênio/genética , Feminino , Expressão Gênica , Genes Supressores de Tumor , Humanos , Proteína 2 Homóloga a MutS , Ativação Transcricional
15.
Br J Cancer ; 90(1): 194-9, 2004 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-14710229

RESUMO

Recently, a LAP protein, scribble, was identified in Drosophila epithelia as a basolateral protein that controls the apical-basolateral polarity. Loss of scribble causes disorganisation and overgrowth of the epithelia. Scribble has a human homologue, human scribble (hScrib), which is a substrate of ubiquitin-mediated degradation by human papillomavirus E6 and the E6AP ubiquitin-protein ligase. In the present study, we revealed that hScrib localised to the basolateral regions of the epithelial cell line MDCK and human uterine cervical epithelial tissues by immunofluorescence. Human scribble colocalised rather with the adherens junction protein E-cadherin, but not with the tight junction protein ZO-1. Histochemical analysis showed a dramatic decrease in the expression of hScrib with the progression of disease from normal uterine cervical tissues to invasive cervical cancers through the precursor lesions. In contrast, the expression of hScrib was retained in the throughout epithelial layer of the HPV-negative cervical high-grade squamous intraepithelial lesions (H-SIL). Although quantitative RT-PCR revealed no significant downregulation of hScrib mRNA expression in the H-SIL, it revealed a clear downregulation in the invasive cancers. These results suggest the possibility that degradation by HPV E6 is one of the causal roles for the progressive decrease of hScrib expression during the disease progression from low-grade squamous intraepithelial lesions to H-SIL, and a cooperative role of downregulation of hScrib mRNA expression and ubiquitin-mediated degradation of hScrib by E6 and E6AP led to the complete decrease of hScrib expression during the process of carcinogenesis from H-SIL to invasive cancer. These data underscore the importance of hScrib in the construction of tissue architecture and prevention of cancer development.


Assuntos
Transformação Celular Neoplásica , Colo do Útero/patologia , Regulação da Expressão Gênica , Proteínas de Membrana/biossíntese , Displasia do Colo do Útero/genética , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/genética , Western Blotting , Linhagem Celular , Colo do Útero/citologia , Progressão da Doença , Regulação para Baixo , Células Epiteliais , Feminino , Imunofluorescência , Humanos , Proteínas de Membrana/análise , Invasividade Neoplásica , Infecções por Papillomavirus/complicações , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor , Neoplasias do Colo do Útero/patologia
16.
Br J Cancer ; 88(8): 1213-6, 2003 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-12698186

RESUMO

We analysed the expression of the fragile histidine triad (FHIT) gene in cervical cancer to evaluate its clinical relevance in relation to human papillomavirus (HPV) infection. A total of 73 women with cervical cancer of stage Ib or more advanced (67 squamous cell carcionomas, four adenocarcinomas, two adenosquamous carcinomas) were examined for Fhit expression by immunohistochemistry. They were further analysed for the presence of HPV and its subtype. Abnormal expression of Fhit (absent or reduced Fhit expression) was observed in 52 cases (71.2%). The high-risk HPV DNAs for cervical cancer, including type 16, 18, 31, 33, 51, 52, 58, 68, were identified in 63 cases (86%). The abnormal Fhit expression was not related to the clinicopathological factors including histology, tumour stage, and HPV type. Notably, the 5-year survival of patients showing the abnormal Fhit expression was significantly poorer than those showing normal Fhit expression (64 versus 87%, P=0.035). Interestingly, the mean age of the patients with the abnormal Fhit expression was significantly less than those with the normal Fhit expression (51.6 versus 58.7 years of age, P=0.027, student's t-test). These data imply that the aberrant Fhit expression could be a poor prognostic factor independent of HPV. In the light of a high incidence of abnormal Fhit expression in younger patients and HPV as a key player in cervical carcinogenesis, abnormal Fhit expression may accelerate carcinogenesis in concert with HPV.


Assuntos
Hidrolases Anidrido Ácido/genética , Proteínas de Neoplasias/genética , Neoplasias do Colo do Útero/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Prognóstico , Análise de Sobrevida , Fatores de Tempo , Infecções Tumorais por Vírus/complicações , Neoplasias do Colo do Útero/mortalidade
17.
Phys Med Biol ; 48(7): 875-89, 2003 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-12701892

RESUMO

Heavy ion therapy has two definite advantages: good dose localization and higher biological effect. Range calculation of the heavy ions is an important factor in treatment planning. X-ray CT numbers are used to estimate the heavy ion range by looking up values in a conversion table which relates empirically photon attenuation in tissues to particle stopping power; this is one source of uncertainty in the treatment planning. Use of positron emitting radioactive beams along with a positron emission tomograph or a positron camera gives range information and may be used as a means of checking in heavy ion treatment planning. However, the metabolism of the implanted positron emitters in a living object is unpredictable because the chemical forms of these emitters are unknown and the metabolism is dependent on the organ species and may be influenced by many factors such as blood flow rate and fluid components present. In this paper, the washout rate of 11C activity implanted by injecting energetic 11C beams into thigh muscle of a rear leg of a rabbit is presented. The washout was found to consist of two components, the shorter one was about 4.2 +/- 1.1 min and the longer one ranged from 91 to 124 min. About one third of the implanted beta+ activity can be used for imaging and the rest was washed out of the target area.


Assuntos
Radioisótopos de Carbono , Músculo Esquelético/diagnóstico por imagem , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada de Emissão/métodos , Animais , Meia-Vida , Radioterapia com Íons Pesados , Transferência Linear de Energia , Músculo Esquelético/efeitos da radiação , Coelhos , Radiografia , Dosagem Radioterapêutica , Coxa da Perna/efeitos da radiação
18.
Water Sci Technol ; 46(9): 147-54, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12448463

RESUMO

A study was carried out to assess the water quality situation of groundwater sources in Kathmandu Valley, Nepal. Groundwater has remained to be a major water supply source for a population of 1.5 million at present in the valley. The focus of this study was to evaluate the extent and sources of groundwater contamination. Water sampling was carried out in selected deep wells and shallow sources. The level of pollution was evaluated by comparing the water quality results with WHO guidelines. The major problems with the dug wells, hand pumps and spouts were found to be the elevated nitrate and mercury contents. The deep wells located on the central aquifer were found to have a serious threat of ammonia pollution. Deep wells were also found to have iron, manganese and mercury concentrations exceeding the guideline values. Multivariate statistical analysis was carried out to cluster the sampling sources and identify the common factors describing the potential sources and possible mechanisms associated with the contaminants. The results suggested that disintegration of the sediment organic matter under strong reducing environment leads to the origin of the unusual water qualities at the central confined aquifer. This process may be microbially mediated and occurs with the simultaneous reduction of species such as arsenic, iron, manganese and sulfate. Both natural and anthropogenic water quality problems were observed in the groundwater system of Kathmandu valley. Attention should be focused to consider distinct strategies to address these problems.


Assuntos
Poluentes do Solo/análise , Poluentes da Água/análise , Abastecimento de Água , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Nepal , Compostos Orgânicos/análise
19.
Appl Microbiol Biotechnol ; 57(1-2): 109-16, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11693906

RESUMO

A highly alkaline endo-1,4-beta-glucanase (Egl) was purified to homogeneity from a culture broth of alkaliphilic Bacillus sp. strain KSM-N252. The optimal pH for activity was as high as 10, and the optimal temperature was 55 degrees C. The molecular mass and isoelectric point were around 50 kDa and pH 4.2, respectively. The enzyme hydrolyzed carboxymethyl cellulose in a random fashion. Unlike previously reported Egls, the enzyme was highly active on p-nitrophenyl cello-oligosaccharides and acid-swollen cellulose, and its activity was stimulated by cellobiose at high concentrations. The entire gene for the enzyme contained a 1,476-bp single open reading frame encoding 492 amino acids, including a 29-amino-acid signal peptide. The mature enzyme (463 amino acids: 51,174 Da) exhibited moderate homology to other family 5 alkaline Egls. In the C-terminal region, a carbohydrate-binding module that belongs to family XII was repeated. Furthermore, four and six repeats of Pro-Pro-Ser/Thr-Glu/Asp-Pro-(Glu) were found immediately before the first and second carbohydrate-binding modules, respectively.


Assuntos
Bacillus/enzimologia , Celulase/isolamento & purificação , Sequência de Aminoácidos , Celobiose/metabolismo , Celulase/química , Celulase/genética , Celulase/metabolismo , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
20.
Rinsho Shinkeigaku ; 41(2-3): 154-6, 2001.
Artigo em Japonês | MEDLINE | ID: mdl-11481862

RESUMO

We report an HIV-positive patient with CNS cryptococcosis, diagnosis of which was based on detection of Cryptococcus neoformans by Indian ink staining and culture of CSF. MRI displayed dilated Virchow-Robin space in bilateral basal ganglia which were hypointense on T1-weighted images, hyperintense on T2-weighted images, and enhanced by gadolinium administration. In addition cryptococcoma in the cerebellum was observed by MRI. This finding may suggest a progression from cryptococcal meningitis to intraparenchymal invasion, accompanied with breakdown of the blood brain barrier.


Assuntos
Criptococose/diagnóstico , Infecções por HIV/complicações , Imageamento por Ressonância Magnética , Meningoencefalite/diagnóstico , Adulto , Gânglios da Base/patologia , Criptococose/etiologia , Humanos , Masculino , Meningoencefalite/etiologia
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