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1.
Sci Total Environ ; 874: 162419, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36858219

RESUMO

Biofiltration, activated carbon and chemical scrubbing are technologies used for odor control in wastewater treatment plants. These systems may also influence the airborne microbial load in treated air. The study objectives were to 1) evaluate the capacity of three odor control system technologies to reduce the airborne concentration of total bacteria, Legionella, L. pneumophila, non-tuberculous mycobacteria (NTM) and Cladosporium in winter and summer seasons and 2) to describe the microbial ecology of the biofiltration system and evaluate its impact on treated air microbial diversity. A reduction of the total bacterial concentration up to 25 times was observed after odor treatment. Quantification by qPCR revealed the presence of Legionella spp. in all air samples ranging between 26 and 1140 GC/m3, while L. pneumophila was not detected except for three samples below the limit of quantification. A significant increase of up to 25-fold of Legionella spp. was noticed at the outlet of two of the three treatment systems. NTM were ubiquitously detected before air treatment (up to 2500 GC/m3) and were significantly reduced by all 3 systems (up to 13-fold). Cladosporium was measured at low concentrations for each system (< 190 GC/m3), with 68 % of the air samples below the limit of detection. Biodiversity results revealed that biofiltration system is an active process that adapts to air pollutants over time. Legionella spp. were detected in significant abundance in the air once treated in winter (up to 27 %). Nevertheless, the abundance of protozoan hosts is low and does not explain the multiplication of Legionella spp. The season remains the most influential factor shaping biodiversity. In summer only, air biofiltration caused a significant enrichment of the biodiversity. Although odor control technologies are not designed for bacterial mitigation, findings from this study suggest their potential to reduce the abundance of some genera harboring pathogenic species.


Assuntos
Poluentes Atmosféricos , Legionella , Purificação da Água , Odorantes , Bactérias , Purificação da Água/métodos , Microbiologia da Água
2.
Water Res ; 108: 57-67, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27825683

RESUMO

Pharmaceuticals are discharged to the environment from wastewater resource recovery facilities, sewer overflows, and illicit sewer connections. To understand the fate of pharmaceuticals, there is a need to better understand their sorption dynamics to suspended sediments (SS) and settled sediments (StS) in sewer systems. In this study, such sorption dynamics to both SS and StS were assessed using a batch equilibrium method under both static and dynamic conditions. Experiments were performed with natively occurring and artificially modified concentrations of sewer pharmaceuticals (acetaminophen, theophylline, carbamazepine, and a metabolite of carbamazepine) and caffeine. Differences in apparent distribution coefficients, Kd,app, between SS and StS were related to differences in their organic carbon (OC) content, and the practice of artificially modifying the concentration. Kd,app values of modified contaminant concentrations and high OC sediments were substantially higher. Pseudo-second order desorption rates for these mobile compounds were also quantified. Successive flushing events to simulate the addition of stormwater to sewer networks revealed that aqueous concentrations would not necessarily decrease, because the added water will rapidly return to equilibrium concentrations with the sediments. Sorption and desorption kinetics must be considered in addition to dilution, to avoid underestimating the influence of dilution on concentrations of pharmaceuticals discharged to the environment.


Assuntos
Cafeína , Águas Residuárias , Sedimentos Geológicos
3.
Environ Sci Process Impacts ; 16(10): 2442-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25189851

RESUMO

A sensitive method was developed to measure the sediment concentration of 10 wastewater micropollutants selected as potential sanitary tracers of sewage contamination and include: nonsteroidal anti-inflammatory drugs (acetaminophen - ACE and diclofenac - DIC), an anti-epileptic drug (carbamazepine - CBZ), a ß-blocker (atenolol - ATL), a stimulant (caffeine - CAF), a bronchodilator (theophylline - THEO), steroid hormones (progesterone - PRO and medroxyprogesterone - MedP), an artificial sweetener (aspartame - APM) and personal care products (N,N-diethyl-3-methylbenzamide - DEET). Natural sediments (combined sewer overflow and stream sediments) were extracted by ultrasonic-assisted extraction followed by solid-phase extraction. Analyses were performed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) using atmospheric pressure chemical ionisation in positive mode (APCI+) with a total analysis time of 4.5 min. Method detection limits were in the range of 0.01 to 15 ng g(-1) dry weight (dw) for the compounds of interest, with recoveries ranging from 75% to 156%. Matrix effects were observed for some compounds, never exceeding |±18%|. All results displayed a good degree of reproducibility and repeatability, with relative standard deviations (RSD) of less than 23% for all compounds. The method was applied to an investigation of stream and combined sewer overflow sediment samples that differed in organic carbon contents and particle size distributions. Acetaminophen, caffeine and theophylline (as confounded with paraxanthine) were ubiquitously detected at 0.13-22 ng g(-1) dw in stream bed sediment samples and 98-427 ng g(-1) dw in combined sewer overflow sediment samples. Atenolol (80.5 ng g(-1) dw) and carbamazepine (54 ng g(-1) dw) were quantified only in combined sewer overflow sediment samples. The highest concentrations were recorded for DEET (14 ng g(-1) dw) and progesterone (11.5 ng g(-1) dw) in stream bed and combined sewer overflow sediment samples, respectively. The ratio of concentration to its limit of detection (C : LOD) in sediments for a subset of compounds were compared to their C : LOD in water. In waters with a large capacity for dilution relative to fecal sources, the C : LOD ranges in sediments were greater than in water. Thus monitoring programs for fecal source tracking using wastewater micropollutants should consider sediment sampling, particularly for waters with highly diluted sources of fecal contamination.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Esgotos/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Limite de Detecção , Águas Residuárias/química
4.
J Environ Monit ; 14(2): 579-88, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22159157

RESUMO

Toxic cyanobacteria threaten the water quality of drinking water sources across the globe. Two such water bodies in Canada (a reservoir on the Yamaska River and a bay of Lake Champlain in Québec) were monitored using a YSI 6600 V2-4 (YSI, Yellow Springs, Ohio, USA) submersible multi-probe measuring in vivo phycocyanin (PC) and chlorophyll-a (Chl-a) fluorescence, pH, dissolved oxygen, conductivity, temperature, and turbidity in parallel. The linearity of the in vivo fluorescence PC and Chl-a probe measurements were validated in the laboratory with Microcystis aeruginosa (r(2) = 0.96 and r(2) = 0.82 respectively). Under environmental conditions, in vivo PC fluorescence was strongly correlated with extracted PC (r = 0.79) while in vivo Chl-a fluorescence had a weaker relationship with extracted Chl-a (r = 0.23). Multiple regression analysis revealed significant correlations between extracted Chl-a, extracted PC and cyanobacterial biovolume and in vivo fluorescence parameters measured by the sensors (i.e. turbidity and pH). This information will help water authorities select the in vivo parameters that are the most useful indicators for monitoring cyanobacteria. Despite highly toxic cyanobacterial bloom development 10 m from the drinking water treatment plant's (DWTP) intake on several sampling dates, low in vivo PC fluorescence, cyanobacterial biovolume, and microcystin concentrations were detected in the plant's untreated water. The reservoir's hydrodynamics appear to have prevented the transport of toxins and cells into the DWTP which would have deteriorated the water quality. The multi-probe readings and toxin analyses provided critical evidence that the DWTP's untreated water was unaffected by the toxic cyanobacterial blooms present in its source water.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Água Potável/microbiologia , Monitoramento Ambiental/instrumentação , Técnicas de Tipagem Bacteriana , Clorofila/análise , Clorofila A , Cianobactérias/classificação , Cianobactérias/isolamento & purificação , Água Potável/química , Monitoramento Ambiental/métodos , Ficocianina/análise , Eliminação de Resíduos Líquidos , Microbiologia da Água
5.
J Water Health ; 9(2): 265-78, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21942192

RESUMO

Indicator organisms are used to assess public health risk in recreational waters, to highlight periods of challenge to drinking water treatment plants, and to determine the effectiveness of treatment and the quality of distributed water. However, many have questioned their efficacy for indicating pathogen risk. Five hundred and forty cases representing independent indicator-pathogen correlations were obtained from the literature for the period 1970-2009. The data were analyzed to assess factors affecting correlations using a logistic regression model considering indicator classes, pathogen classes, water types, pathogen sources, sample size, the number of samples with pathogens, the detection method, year of publication and statistical methods. Although no single indicator was identified as the most correlated with pathogens, coliphages, F-specific coliphages, Clostridium perfringens, fecal streptococci and total coliforms were more likely than other indicators to be correlated with pathogens. The most important factors in determining correlations between indicator-pathogen pairs were the sample size and the number of samples positive for pathogens. Pathogen sources, detection methods and other variables have little influence on correlations between indicators and pathogens. Results suggest that much of the controversy with regards to indicator and pathogen correlations is the result of studies with insufficient data for assessing correlations.


Assuntos
Monitoramento Ambiental/métodos , Microbiologia da Água , Abastecimento de Água , Animais , Fezes/microbiologia , Humanos , Indicadores e Reagentes , Modelos Logísticos , Recreação , Esgotos , Eliminação de Resíduos Líquidos
6.
J Water Health ; 9(1): 94-106, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21301118

RESUMO

The objective of this study was to characterize the variability of Escherichia coli density and sources in an urban watershed, particularly to focus on the influences of weather and land use. E. coli as a microbial indicator was measured at fourteen sites in four wet weather events and four dry weather conditions in the upper Blackstone River watershed. The sources of E. coli were identified by ribotyping. The results showed that wet weather led to sharp increases of E. coli densities. Interestingly, an intense storm of short duration led to a higher E. coli density than a moderate storm of long duration (p<0.01). The ribotyping patterns revealed microbial sources were mainly attributed to humans and wildlife, but varied in different weather conditions and were associated with the patterns of land use. Human sources accounted for 24.43% in wet weather but only 9.09% in dry weather. In addition, human sources were more frequently observed in residential zones (>30% of the total sources), while wildlife sources were dominant in open land and forest zones (54%). The findings provide useful information for developing optimal management strategies aimed at reducing the level of pathogens in urban watersheds.


Assuntos
Monitoramento Ambiental/métodos , Escherichia coli/classificação , Escherichia coli/genética , Água Doce/microbiologia , Animais , Animais Selvagens/microbiologia , Contagem de Colônia Microbiana/métodos , Conservação dos Recursos Naturais , Escherichia coli/isolamento & purificação , Genes Bacterianos , Atividades Humanas , Humanos , Massachusetts , Densidade Demográfica , Ribotipagem , Poluição da Água/análise , Tempo (Meteorologia)
7.
J Environ Monit ; 13(2): 455-63, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21157617

RESUMO

The source water of a drinking water treatment plant prone to blooms, dominated by potential microcystin-producing cyanobacteria, was monitored for two seasons in 2007-2008. In the 2008 season, the median value for potential microcystin-producing cyanobacterial biovolume was 87% of the total phytoplankton biovolume in the untreated water of the plant. Depth profiles taken above the plant's intake identified three sampling days at high risk for the contamination of the plant's raw water with potentially toxic cyanobacteria. Chlorophyceae and Bacillariophyceae caused false positive values to be generated by the phycocyanin probe when cyanobacteria represented a small fraction of the total phytoplanktonic biovolume present. However, there was little interference with the phycocyanin probe readings by other algal species when potential microcystin-producing cyanobacteria dominated the phytoplankton of the plant's untreated water. A two-tiered method for source water monitoring, using in vivo phycocyanin fluorescence, is proposed based on (1) a significant relationship between in vivo phycocyanin fluorescence and cyanobacterial biovolume and (2) the calculated maximum potential microcystin concentration produced by dominant Microcystis sp. biovolume. This method monitors locally-generated threshold values for cyanobacterial biovolume and microcystin concentrations using in vivo phycocyanin fluorescence.


Assuntos
Biomassa , Cianobactérias/citologia , Água Doce/microbiologia , Ficocianina/metabolismo , Abastecimento de Água , Canadá , Cianobactérias/metabolismo , Fluorescência , Microcystis/citologia , Microcystis/metabolismo , Estações do Ano , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos
8.
J Inherit Metab Dis ; 29(5): 683, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16972175

RESUMO

Fumaric aciduria is a rare, autosomal recessive disorder caused by deficient activity of fumarate hydratase (FH). Common clinical features are hypotonia, failure to thrive, severe psychomotor retardation and seizures. Facial dysmorphism and brain malformations are frequent. Recently, some FH gene mutations have been associated with inherited cutaneous and uterine leiomyomas and papillary renal cell cancer. Our patient had a relatively mild phenotype, a previously not reported genotype and familial tumour predisposition. The mother and grandmother had uterine myomas. The paternal grandfather and his two brothers died from lung and laryngeal cancers. The pregnancy was complicated by bleeding and intrauterine growth retardation. Delivery was after 35 weeks, with normal Apgar score. The girl was hypotonic since birth. At age 2 months the parents noticed short apnoeic crises. She could sit at age 1.5 years, and walk with assistance at 4 years. At age 8 years highly increased excretion of fumaric acid was found twice (217 and 445 mmol/mol creatinine). Shortly before that the girl started to have leg and arm spasms. Grand mal seizures occurred twice. Facial dysmorphism included depressed nasal bridge, anteverted ears, hypertelorism and microcephaly. Speech was limited to few disyllables. She was atactic with spastic paraparesis. Brain MRI showed slight ventriculomegaly, white-matter atrophy and hypoplasia of corpus callosum. Activity of FH in fibroblasts was 1.9 nmol/min/mg protein (controls 40-80). Analysis of the FH gene revealed the maternally derived c.1029_1031delAGT mutation, resulting in Val deletion and substitution of Gln by His, and paternally derived c.976C > T mutation, resulting in substitution of Pro by Ser.


Assuntos
Fumarato Hidratase/deficiência , Fumarato Hidratase/genética , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/genética , Mutação , Encéfalo/patologia , Criança , Saúde da Família , Feminino , Humanos , Imageamento por Ressonância Magnética , Erros Inatos do Metabolismo/patologia , Fenótipo
9.
Biochem Soc Trans ; 30(Pt 6): 1131-6, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12440989

RESUMO

The proteins in a living cell are synthesized on a large bipartite ribonucleoprotein complex termed the ribosome. The peptidyl transferase, which polymerizes amino acids to yield peptides, is localized on the large subunit. Biochemical investigations over the past 35 years have led to the hypothesis that rRNA has a major role in all ribosomal functions. The recent high resolution X-ray structures of the ribosomal subunits clearly demonstrated that peptidyl transfer is an RNA-mediated process. As all ribosomal activities are dependent on bivalent metal ions, as is the case for most ribozymes, we investigated metal-ion-binding sites in rRNA by metal-ion-cleavage reactions. Some cleavage sites are near active sites and are evolutionarily highly conserved. The structure of the active site is flexible and undergoes changes during translocation and activation of the ribosome. Using modified P-site substrates, we showed that the 2'-OH group of the terminal adenosine is important for peptidyl transfer. These substrates were also used to investigate the metal ion dependency of the peptidyl transferase reaction.


Assuntos
Peptidil Transferases/química , RNA Ribossômico 23S/genética , Sequência de Bases , Cromatografia em Camada Fina , Modelos Químicos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Peptídeos/química , Peptidil Transferases/genética , Peptidil Transferases/metabolismo , RNA Ribossômico 23S/metabolismo
10.
Artigo em Alemão | MEDLINE | ID: mdl-12506753

RESUMO

The detection of disseminated tumor cells in bone marrow and blood is increasingly used for staging and therapeutic decisions in breast cancer and other solid tumors. Molecular biological methods improve the diagnostic accuracy. Limitations of the approach relate to the lack of disease-specific marker genes. The detection of tumor cells in the bone marrow after primary therapy is a negative prognostic parameter in many solid tumours. Axillary lymph node dissection and histopathology remain the standard staging procedure in breast cancer, but nodal negative patients exhibiting tumor cells in the bone marrow have an inferior outcome and may benefit from adjuvant therapy. The immunohistochemical and molecular detection of tumour cells in lymph nodes reduces the number of truly nodal-negative patients considerably. Tumour cells in bone marrow and blood may be used to directly monitor therapeutic responses.


Assuntos
Neoplasia Residual/diagnóstico , Neoplasia Residual/terapia , Neoplasias/terapia , Humanos , Neoplasia Residual/genética , Reação em Cadeia da Polimerase , Prognóstico
11.
Eur J Haematol ; 67(2): 128-32, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11722602

RESUMO

We describe in detail a 67-yr-old woman who was treated with a cytostatic combination chemotherapy for newly diagnosed common-acute lymphoblastic leukaemia. At the end of induction therapy, the patient acquired invasive mould infection affecting lung and brain. The patient entered complete remission of her leukaemia. Treatment with liposomal amphotericin B was initiated along with surgical excision of the fungal brain abscess. Intrathecal instillation of amphotericin B deoxycholate was started using an Ommaya reservoir because of an anatomical connection between the postoperative cavity and the ventricle. Full dose cytostatic chemotherapy was continued with little delay. A computerised tomography scan of the chest performed 2 months later revealed no fungal abscesses. Magnetic resonance imaging of the brain did not reveal any fungal manifestation. During maintenance therapy/week 69, the patient relapsed from leukaemia. High doses of intravenous liposomal amphotericin B were administered prophylactically. The patient's leukaemia proved refractory to reinduction chemotherapy and the patient died from pneumonia 8 wk later. Post mortem microbiological investigation and histopathological examination of lung and brain tissue did not reveal any macroscopical or microscopical fungal manifestations. This case underlines the feasibility and successful application of combined antileukaemic, antifungal and surgical therapy in a patient with acute leukaemia.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Abscesso Encefálico/tratamento farmacológico , Abscesso Pulmonar/tratamento farmacológico , Pneumopatias Fúngicas/tratamento farmacológico , Neuroaspergilose/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/complicações , Idoso , Anfotericina B/administração & dosagem , Anfotericina B/efeitos adversos , Antifúngicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Abscesso Encefálico/diagnóstico , Abscesso Encefálico/microbiologia , Abscesso Encefálico/cirurgia , Terapia Combinada , Craniotomia , Ácido Desoxicólico/administração & dosagem , Ácido Desoxicólico/efeitos adversos , Ácido Desoxicólico/uso terapêutico , Combinação de Medicamentos , Evolução Fatal , Feminino , Humanos , Hospedeiro Imunocomprometido , Infusões Intravenosas , Injeções Espinhais , Lipossomos , Abscesso Pulmonar/diagnóstico , Abscesso Pulmonar/microbiologia , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/microbiologia , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia , Neuroaspergilose/diagnóstico , Neuroaspergilose/microbiologia , Neuroaspergilose/cirurgia , Pneumonia Pneumocócica/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Indução de Remissão , Tomografia Computadorizada por Raios X
12.
Proc Natl Acad Sci U S A ; 98(18): 10096-101, 2001 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-11517305

RESUMO

The ribosome is a dynamic particle that undergoes many structural changes during translation. We show through chemical probing with dimethyl sulfate (DMS) that conformational changes occur at several nucleotides in the peptidyl transferase center upon alterations in pH, temperature, and monovalent ion concentration, consistent with observations made by Elson and coworkers over 30 years ago. Moreover, we have found that the pH-dependent DMS reactivity of A2451 in the center of the 23S rRNA peptidyl transferase region, ascribed to a perturbed pKa of this base, occurs only in inactive 50S and 70S ribosomes. The degree of DMS reactivity of this base in the inactive ribosomes depends on both the identity and amount of monovalent ion present. Furthermore, G2447, a residue proposed to be critical for the hypothesized pKa perturbation, is not essential for the conditional DMS reactivity at A2451. Given that the pH-dependent change in DMS reactivity at A2451 occurs only in inactive ribosomes, and that this DMS reactivity can increase with increasing salt (independently of pH), we conclude that this observation cannot be used as supporting evidence for a recently proposed model of acid/base catalyzed ribosomal transpeptidation.


Assuntos
Peptidil Transferases/química , Ribossomos/enzimologia , Sequência de Bases , Escherichia coli/enzimologia , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Peptidil Transferases/genética , Mutação Puntual , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Ribossômico/química , RNA Ribossômico/genética , Ribossomos/genética , Ésteres do Ácido Sulfúrico
14.
Acta Med Austriaca Suppl ; 52: 37-9, 2000.
Artigo em Alemão | MEDLINE | ID: mdl-11261277

RESUMO

Neuroendocrine carcinoma and small-cell lung cancer (SCLC) are highly responsive to chemo- and radiotherapy. Nevertheless, most patients (pts.) experience relapse. At the 2nd department of medicine in the Donauspital, 4 pts. with neuroendocrine carcinomas of different primary sites underwent high-dose chemotherapy with autologous stem-cell transplantation (ASTx). Pt. 1 suffered from neuroendocrine lung cancer, pt. 2 from a small-cell carcinoma of the pancreas. Pt. 3 had a metastatic small-cell abdominal bulky tumor and pt. 4 presented with neuroendocrine carcinoma of the prostate. After 4-6 cycles induction chemotherapy pts. were consolidated with 1 cycle of HDCht and ASTx. Prior to HDCht pt. 1 and pt. 2 were in complete remission (CR) and pt. 3 and pt. 4 in partial remission. Pt. 3 converted in CR after HDCht. He is still in CR with a disease-free survival of 23 month after ASTx and 30 month after diagnosis. Pt. 1, 2 and 4 died from relapse 10, 16 and 5 month after ASTx and 16, 22 and 9 month after diagnosis. Pts. with neuroendocrine carcinomas might be suitable candidates for HDCht and ASTx.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas , Neoplasias Pulmonares/tratamento farmacológico , Tumores Neuroendócrinos/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Pequenas/patologia , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/patologia , Taxa de Sobrevida
15.
Genes Dev ; 13(8): 987-1001, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10215626

RESUMO

SR proteins are nuclear phosphoproteins with a characteristic Ser/Arg-rich domain and one or two RNA recognition motifs. They are highly conserved in animals and plants and play important roles in spliceosome assembly and alternative splicing regulation. We have now isolated and partially sequenced a plant protein, which crossreacts with antibodies to human SR proteins. The sequence of the corresponding cDNA and genomic clones from Arabidopsis revealed a protein, atSRp30, with strong similarity to the human SR protein SF2/ASF and to atSRp34/SR1, a previously identified SR protein, indicating that plants possess two SF2/ASF-like proteins. atSRp30 expresses alternatively spliced mRNA isoforms that are expressed differentially in various organs and during development. Overexpression of atSRp30 via a strong constitutive promoter resulted in changes in alternative splicing of several endogenous plant genes, including atSRp30 itself. Interestingly, atSRp30 overexpression resulted in a pronounced down-regulation of endogenous mRNA encoding full-length atSRp34/SR1 protein. Transgenic plants overexpressing atSRp30 showed morphological and developmental changes affecting mostly developmental phase transitions. atSRp30- and atSRp34/SR1-promoter-GUS constructs exhibited complementary expression patterns during early seedling development and root formation, with overlapping expression in floral tissues. The results of the structural and expression analyses of both genes suggest that atSRp34/SR1 acts as a general splicing factor, whereas atSRp30 functions as a specific splicing modulator.


Assuntos
Processamento Alternativo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Sequência de Bases , DNA de Plantas , Genoma de Planta , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/genética , Fenótipo , Fosfoproteínas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Fatores de Processamento de Serina-Arginina , Spliceossomos , Transcrição Gênica
16.
Biol Chem ; 380(2): 243-51, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10195431

RESUMO

Divalent metal ions are absolutely required for the structure and catalytic activities of ribosomes. They are partly coordinated to highly structured RNA, which therefore possesses high-affinity metal ion binding pockets. As metal ion induced RNA cleavages are useful for characterising metal ion binding sites and RNA structures, we analysed europium (Eu3+) induced specific cleavages in both 16S and 23S rRNA of E. coli. The cleavage sites were identified by primer extension and compared to those previously identified for calcium, lead, magnesium, and manganese ions. Several Eu3+ cleavage sites, mostly those at which a general metal ion binding site had been already identified, were identical to previously described divalent metal ions. Overall, the Eu3+ cleavages are most similar to the Ca2+ cleavage pattern, probably due to a similar ion radius. Interestingly, several cleavage sites which were specific for Eu3+ were located in regions implicated in the binding of tRNA and antibiotics. The binding of erythromycin and chloramphenicol, but not tetracycline and streptomycin, significantly reduced Eu3+ cleavage efficiencies in the peptidyl transferase center. The identification of specific Eu3+ binding sites near the active sites on the ribosome will allow to use the fluorescent properties of europium for probing the environment of metal ion binding pockets at the ribosome's active center.


Assuntos
Európio/metabolismo , RNA Ribossômico 16S/metabolismo , RNA Ribossômico/metabolismo , Antibacterianos/metabolismo , Sequência de Bases , Cátions , Cloranfenicol/metabolismo , Eritromicina/metabolismo , Escherichia coli/genética , Dados de Sequência Molecular , RNA Bacteriano/metabolismo , RNA Ribossômico/química , RNA Ribossômico 16S/química , Ribossomos , Estreptomicina/metabolismo
17.
Dev Med Child Neurol ; 27(4): 461-6, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3896902

RESUMO

Sixteen families were contacted two to seven years after the death of their spina-bifida baby following transfer to a specialist unit and the parents' subsequent decision against active treatment. There was little evidence of serious long-term problems of adjustment on any of the measures assessing marital relationships, parental physical and mental health, and decisions about later pregnancies. Parents welcomed the unit's policy of encouraging frequent contact with their baby, and thought that it had facilitated the grieving process.


Assuntos
Adaptação Psicológica , Pesar , Relações Pais-Filho , Espinha Bífida Oculta/psicologia , Adulto , Atitude Frente a Morte , Características da Família , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Casamento , Testes Psicológicos , Espinha Bífida Oculta/terapia
18.
Arch Dis Child ; 53(8): 611-9, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-708096

RESUMO

Neurological and psycholocial assessment was carried out on 30 patients aged 2.7 to 21 years (mean 9.4) who were being treated for hypothyroidism starting before the age of 2 years. Their IQ scores lay in the normal range (71--122; mean 92.4) but 77% showed at least one sign of impaired brain function. Clumsiness was found in 33%, behaviour disorders in 23%, speech disorders in 20%, learning disorders in 26%, squint in 53%, nystagmus in 10%, and minor motor disorders in 50%. Many showed several of these features and hypothyroidism in early life appears to lead to widespeard impairment of brain function. These neurological findings were equally common in patients in whom treatment started between 4 and 10 weeks of age and patients treated after 10 weeks, suggesting that early detection of hypothyroidism by neonatal screening may be of limited benefit. Children who have been hypothyroid in early infancy require careful assessment to prevent further visual, emotional, scholastic, or vocational difficulties.


Assuntos
Encefalopatias/etiologia , Hipotireoidismo/complicações , Adolescente , Adulto , Criança , Transtornos do Comportamento Infantil/etiologia , Pré-Escolar , Hipotireoidismo Congênito , Oftalmopatias/etiologia , Feminino , Humanos , Hipotireoidismo/psicologia , Inteligência , Masculino , Atividade Motora , Transtornos dos Movimentos/etiologia
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