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1.
Mol Hum Reprod ; 28(12)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36370081

RESUMO

Successful implantation requires a fine-tuned dialog between the invading embryo and the maternal endometrium. Recently, we discovered that premature senescence of endometrial stromal cells (EnSC) might mediate improper decidual transformation of endometrial tissue and impair endometrial-blastocyst interaction. Here, we show that senescent EnSC are characterized by elevated intracellular reactive oxygen species (ROS) levels that originate from mitochondrial dysfunction and insufficient antioxidant defense. Decidualization of senescent EnSC is defective and is accompanied by the elevated intracellular and mitochondrial ROS levels. Antioxidant defense during decidualization is significantly less efficient in senescent EnSC compared to healthy ones. Senescent EnSC secrete increased amounts of ROS into the extracellular space. Elevated ROS released by senescent EnSC shift the redox balance and induce DNA damage in the neighboring trophoblast-like cells. In an in vitro implantation model, we observed impaired spreading of blastocyst-like spheroids into a monolayer of decidualizing senescent EnSC, which could be compensated by pretreatment of the senescent cells with the antioxidant, Tempol. Hence, we propose a possible mechanism that might be responsible, at least in part, for the defective embryo implantation realized via ROS transmitting from senescent EnSC to trophoblast cells. Such transmission results in the accumulation of ROS and subsequent DNA damage in trophoblastic cells, which might lead to improper migration and invasion of an embryo. In light of these findings, the application of antioxidants prior to implantation might be a promising strategy to improve implantation efficiency.


Assuntos
Antioxidantes , Trofoblastos , Feminino , Humanos , Espécies Reativas de Oxigênio , Antioxidantes/farmacologia , Células Estromais , Implantação do Embrião , Blastocisto , Endométrio
2.
Org Biomol Chem ; 13(13): 4064-9, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25733161

RESUMO

6-Sulfamoyl-saccharin was investigated as an inhibitor of 11 α-carbonic anhydrase (CA, EC 4.2.1.1) isoforms of human (h) origin, hCA I-XIV, and X-ray crystallographic data were obtained for its adduct with hCA II, the physiologically dominant isoform. This compound possesses two potential zinc-binding groups, the primary sulfamoyl one and the secondary, acylatedsulfonamide. Saccharin itself binds to the Zn(II) ion from the CA active site coordinating with this last group, in deprotonated (SO2N(-)CO) form. Here we explain why 6-sulfamoyl-saccharin, unlike saccharin, binds to the metal ion from the hCA II active site by its primary sulfonamide moiety and not the secondary one as saccharin itself. Our study is useful for shedding new light to the structure-based drug design of isoform-selective CA inhibitors of the sulfonamide type.


Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/química , Anidrases Carbônicas/metabolismo , Sacarina/análogos & derivados , Sacarina/farmacologia , Sulfonamidas/farmacologia , Inibidores da Anidrase Carbônica/química , Domínio Catalítico , Cristalografia por Raios X , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/química , Isoenzimas/metabolismo , Cinética , Modelos Moleculares , Sacarina/química , Sulfonamidas/química
5.
J Med Econ ; 15(3): 601-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22376190

RESUMO

OBJECTIVE: To compare rates of severe relapse and total direct and indirect costs over a 2-year period between US-based employees with multiple sclerosis (MS) who were adherent and non-adherent to disease-modifying drugs (DMDs). METHODS: Employees with ≥1 MS diagnosis (ICD-9-CM: 340.x) and ≥1 DMD pharmacy claim between 1/1/2002-12/31/2007 were identified from a large US administrative claims database. Patients had continuous coverage ≥6 months before (baseline) and ≥24 months after (study period) their index date (first DMD claim). Adherence was measured using medication possession ratio (MPR) over the study period. Patients with MPR ≥80% were considered adherent (n = 448) and those with MPR <80% as non-adherent (n = 200). Multivariate analyses were used to compare rates of severe relapse (inpatient or Emergency Department visit with MS diagnosis) and costs in 2007 dollars between DMD adherent and non-adherent patients. Direct costs were calculated as reimbursements to providers for medical services and prescription drugs excluding DMDs. Indirect costs included disability and medically-related absenteeism costs. RESULTS: DMD adherent patients were on average older (43.5 vs 41.8 years, p = 0.015) and more likely to be male (38.6% vs 26.0%, p = 0.002) compared with non-adherent patients. Adherent patients had lower rates of depression, higher rates of previous DMD use, and higher baseline MS-related costs. After adjusting for differences in baseline characteristics, DMD adherent patients had a lower rate of severe relapse (12.4% vs 19.9%, p = 0.013) and lower total (direct and indirect) costs ($14,095 vs $16,638, p = 0.048) over the 2-year study period. CONCLUSIONS: In this study, DMD adherence was associated with a significantly lower rate of severe relapse and lower total costs over 2 years. Causality cannot be inferred because adherence and outcomes were measured over the same period. The study was subject to limitations associated with use of claims data and the absence of clinical measures.


Assuntos
Emprego , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/prevenção & controle , Cooperação do Paciente , Adulto , Custos e Análise de Custo , Bases de Dados Factuais , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hospitalização , Humanos , Revisão da Utilização de Seguros , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Índice de Gravidade de Doença , Estados Unidos
6.
J Asthma ; 46(1): 67-72, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19191141

RESUMO

OBJECTIVES: This study was performed to determine whether pulmonary function test results would appreciably alter asthma severity categorization determined by an algorithm using information readily available in administrative databases. METHODS: Patients 6 to 64 years of age with asthma diagnosed from 1999-2005, who had at least one pulmonary function test, were identified from a claims database of a medical group practice located in central Massachusetts. Asthma severity for these patients was categorized using information available in an administrative database (claims-based algorithm) and by percent predicted forced expiratory volume in 1 second (FEV(1)) or peak expiratory flow (PEF) abstracted from medical charts (pulmonary function test method). Gamma rank correlation index was used to measure the association between the two severity categorization methods. Total and asthma-related healthcare costs for each severity category were compared between the two different approaches. RESULTS: There was a significant ordinal association between severity categorization with the two classification approaches (p = 0.0002). The pulmonary function test method resulted in more frequent mild categorizations and less frequent moderate and severe categorizations than the claims-based algorithm. In only 10.9% of patients did the pulmonary function test method result in a more severe asthma category than the claims-based algorithm. Patients with more severe asthma, determined by both methods, had higher total and asthma-related health care costs. Total and asthma-related health care costs were similar for each asthma severity categorization for the two classification approaches, except for asthma-related costs in the moderate severity categories. CONCLUSION: The claims-based algorithm generally categorized patients as having more severe asthma than the approach using pulmonary function test results. Pulmonary function test results would have appreciably changed asthma severity categorization in only a small percent of patients. These findings add further support to the use of administrative database analyses for the evaluation of asthma care in large populations.


Assuntos
Algoritmos , Asma/diagnóstico , Asma/economia , Gastos em Saúde , Adolescente , Adulto , Assistência Ambulatorial/economia , Asma/fisiopatologia , Criança , Serviço Hospitalar de Emergência/economia , Hospitalização/economia , Humanos , Massachusetts , Sistemas Computadorizados de Registros Médicos , Pessoa de Meia-Idade , Medicamentos sob Prescrição/economia , Testes de Função Respiratória , Adulto Jovem
7.
Cell Mol Neurobiol ; 26(2): 127-44, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16763780

RESUMO

1. The HCS2 (Helix command specific 2) gene expressed in giant command neurons for withdrawal behavior of the terrestrial snail Helix lucorum encodes a unique hybrid precursor protein that contains a Ca-binding (EF-hand motif) protein and four small peptides (CNP1-CNP4) with similar Tyr-Pro-Arg-X aminoacid sequence at the C terminus. Previous studies suggest that under conditions of increased intracellular Ca(2+) concentration the HCS2 peptide precursor may be cleaved, and small physiologically active peptides transported to the release sites. In the present paper, intracellular localization of putative peptide products of the HCS2-encoded precursor was studied immunocytochemically by means of light and electron microscopy. 2. Polyclonal antibodies against the CNP3 neuropeptide and a Ca-binding domain of the precursor protein were used for gold labeling of ultrathin sections of identified isolated neurons maintained in culture for several days, and in same identified neurons freshly isolated from the central nervous system. 3. In freshly isolated neurons, the gold particles were mainly localized over the cytoplasmic secretory granules, with the density of labeling for the CNP3 neuropeptide being two-fold higher than for the calcium-binding domain. In cultured neurons, both antibodies mostly labeled clusters of secretory granules in growth cones and neurites of the neuron. The density of labeling for cultured neurons was the same for both antibodies, and was two-fold higher than for the freshly isolated from the central nervous system neurons. 4. The immunogold particles were practically absent in the bodies of cultured neurons. 5. The data obtained conform to the suggestion that the HCS2 gene products are transported from the cell body to the regions of growth or release sites.


Assuntos
Proteínas de Ligação ao Cálcio/análise , Caracois Helix/química , Neurônios/química , Neuropeptídeos/análise , Animais , Caracois Helix/anatomia & histologia , Imuno-Histoquímica , Interneurônios/química , Interneurônios/ultraestrutura , Neurônios/ultraestrutura , Peptídeos/análise
8.
J Appl Microbiol ; 93(5): 751-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12392519

RESUMO

AIMS: To evaluate the lytic activities of crude enzymes from Cytophaga sp. LR2 on Rhodella reticulata cells and isolated algal polysaccharide. METHODS AND RESULTS: The Cytophaga compartment was separated after centrifugation in a cell suspension for 30 min at 18,000 g. The extracellular enzyme was obtained from the supernatant and the intracellular from the pelleted cells after sonication and removal of debris. Algal cells were incubated with extra- or intracellular preparations and sowed onto agar medium. The suppressive effect of the extracellular enzyme on colony-forming units was found to be almost twice as high. The result was still more pronounced when treated cells had been shocked osmotically before seeding. Saccharolytic activity was evaluated by changes in the reducing sugars in the media. Concerning isolated algal polysaccharide, the reducing power of the two bacterial preparates was relatively low. A combined fraction showed the highest lytic activity. Using native and SDS electrophoresis some relation between the prevalence of the extra and intracellular protein patterns was registered. Two of the common components' molecular weight masses of 50 and 21 kDa were found to be reproducible in native- and SDS-containing gel. CONCLUSIONS: Cytophaga sp. LR2 produce extra- and intracellular enzymes active in destroying Rhodella cultures. The agents excreted in the medium are more effective.We suppose that two or three different classes of enzymes are involved in the lysis process. The comparative electrophoresis in this case shows the protein components with predictable functions. SIGNIFICANCE AND IMPACT OF THE STUDY: Combining different simple and reproducible approaches to identify the lytic capability of Cytophaga sp. LR2 on R. reticulata.


Assuntos
Cytophaga/fisiologia , Espaço Extracelular/enzimologia , Líquido Intracelular/enzimologia , Rodófitas/microbiologia , Contagem de Células , Cytophaga/crescimento & desenvolvimento , Cytophaga/metabolismo , Eletroforese em Gel de Poliacrilamida , Espaço Extracelular/metabolismo , Glucose/metabolismo , Líquido Intracelular/metabolismo , Polissacarídeos/metabolismo , Rodófitas/enzimologia , Rodófitas/crescimento & desenvolvimento
9.
J Appl Microbiol ; 93(3): 497-504, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12174050

RESUMO

AIMS: To define the role of the bacterial strains LR1 and LR3 in the Rhodella cell destruction caused by Cytophaga sp.LR2. METHODS AND RESULTS: The bacteria were obtained from algal culture with destruction. They were isolated in pure culture and tested for biochemical activities using Polymicrotest. The ability of bacteria to degrade and utilize the algal polysaccharide was investigated. The bacteria were grown in a media containing Rhodella polysaccharide as a sole carbon source. The level of the reducing sugars in the culture media was determined. Scanning electron microscopy (SEM) was used to define the location of bacteria in extensively and intensively cultivated Rhodella reticulata previously infected by Cytophaga sp. LR2. CONCLUSIONS: The lysis of Rhodella reticulata cells is due to the joint action of the three bacterial strains with the former pathogen Cytophaga sp. LR2 playing the main role. The accumulation of the polysaccharide and the excreted metabolites of the strains LR1 and LR3 stimulated the development of Cytophaga sp. LR2. The adaptation of the strain to particular conditions of alga cultivation and the utilization of polysaccharide as a sole carbon source supported its stable growth in alga suspension and destruction of Rhodella cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The predominance of Cytophaga sp. LR2 over the two other contaminants and the lysis of Rhodella reticulata cells resulted from the ability of the bacterium to attach to the algal polysaccharide sheath. The formation of slime and extrusions facilitated the phenomenon of bacterial adhesion to the algal surface as well as the formation of colonial alga - bacterial spherules. The sedimentation of these aggregates decreased the ability of the algal strain to photosynthesize, led to the lysis of the cells and finally caused the death of Rhodella.


Assuntos
Bactérias/crescimento & desenvolvimento , Polissacarídeos/metabolismo , Rodófitas/microbiologia , Bactérias/isolamento & purificação , Bactérias/metabolismo , Meios de Cultura , Cytophaga/crescimento & desenvolvimento , Cytophaga/isolamento & purificação , Cytophaga/metabolismo , Microscopia Eletrônica de Varredura , Rodófitas/crescimento & desenvolvimento , Rodófitas/ultraestrutura
10.
Sci Total Environ ; 280(1-3): 85-91, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11763275

RESUMO

The concentrations of lanthanoids, Be, Bi,Ga, Te, Tl, Th and U have been determined using ICP-MS for 100 standardized samples of poplar leaves collected from the territory of Bulgaria. The investigated elements are log-normally distributed on the territory. Using cluster analysis of the analytical data the samples were grouped according soil type on which the plants are growing.


Assuntos
Elementos da Série dos Lantanídeos/análise , Salicaceae , Poluentes do Solo/análise , Bulgária , Monitoramento Ambiental , Folhas de Planta/química , Distribuição Tecidual
11.
Talanta ; 54(4): 567-74, 2001 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18968278

RESUMO

Four digestion procedures for microwave dissolution of soils and sediments are investigated. Accurate results (accuracy better than 10%) for lanthanides, Be, Bi, Te, Th, U and Y are obtained only after an overnight stay with a mixture of 2 ml 48% HF and 2 ml 65% HNO(3) and afterwards stepwise microwave digestion with 1 ml 48% HF and 10 ml 5% H(3)BO(3). Only As is not be to be determined by this procedure due to significant interferences from Eu, Nd and Sm. For all other elements, accurate results are obtained by all four procedures.

12.
Proc AMIA Symp ; : 699-703, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11079974

RESUMO

Many healthcare organizations utilize network "firewalls" to protect their networks from being accessed by unauthorized external entities. These same firewalls are also often configured to deny access to certain external services from within the internal network. The latter policy can be subverted through a "protocol tunneling" strategy, which has been implemented as a set of programs called "Firehole." Organizations should be aware of this potential weakness in their network security designs. Policies that deny external services to users should be carefully evaluated in light of clearly defined organizational goals.


Assuntos
Redes de Comunicação de Computadores , Segurança Computacional , Sistemas de Informação , Internet
13.
J Appl Microbiol ; 88(2): 358-63, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10736006

RESUMO

The influence of different factors on the lysis of the red microalga, Rhodella reticulata, by Cytophaga sp. LR2 was studied. The pathogenic bacterial strain was more resistant than the alga to the physiological parameters studied, which assured long-term survival of bacteria in algal cultures. Cytophaga sp. LR2 infected R. reticulata at temperatures between 15 and 30 degrees C, in the illuminated as well as the non-illuminated cultures, at pH values between 5.0 and 9.0, and in the presence of NaCl and CaCl2 in the culture medium. SEM showed a different morphology of the bacteria in algal cultures from those of axenic cultures of Cytophaga. Observations of specific associations between algal and bacterial cells revealed that the role of the slime extrusions on the bacterial surface was attachment of Cytophaga to algal cells, and that their clumping leads to rapid lysis.


Assuntos
Cytophaga/fisiologia , Rodófitas/microbiologia , Rodófitas/fisiologia , Meios de Cultura , Microscopia Eletrônica de Varredura
14.
Crisis ; 21(3): 144-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11265841
15.
Eur J Cell Biol ; 65(1): 60-9, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7889996

RESUMO

A comparative study on the localization of free cytosolic tryptophanyl-tRNA synthetase (TrpRS) and several components of the multi-aminoacyl-tRNA synthetase (ARS) complex (glutamyl-prolyl-tRNA synthetase (GluProRS), arginyl-tRNA synthetase (ArgRS)), and two non-synthetase polypeptides p38 and p43 has been carried out on ultrathin sections of cultured rabbit kidney cells by the immunogold technique using monoclonal antibodies raised against appropriate polypeptides. It has been shown that GluProRS, ArgRS and p38 polypeptide are distributed in the cells similarly to TrpRS and are located mainly in the vicinity of ribosomes. A smaller but significant portion of these proteins has been observed in the nuclei in the diffuse chromatin regions and in the vicinity of interchromatin granules. On the contrary, the main part of p43 protein was found in the cell nuclei; this indicates that this protein may exist in the cell separately from the cytoplasmic multi-ARS complex. Our results argue in favor of compartmentalization of both free ARS (such as TrpRS) and the multi-ARS complex in the vicinity of ribosomes. At the same time, the detection of some ARS in the diffuse chromatin regions in the nucleus implies that these enzymes may exhibit some non-canonical functions in addition to their role in protein synthesis.


Assuntos
Arginina-tRNA Ligase/análise , Compartimento Celular/fisiologia , Glutamato-tRNA Ligase/análise , Biossíntese de Proteínas , Triptofano-tRNA Ligase/análise , Animais , Linhagem Celular , Peso Molecular , Peptídeos/análise , Coelhos
16.
Eur J Cell Biol ; 62(2): 248-58, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7925483

RESUMO

Monoclonal antibody Am1 against conservative epitope of tryptophanyl-tRNA synthetase (WRS) was labeled with colloidal gold particles and used to localize the enzyme on ultrathin sections of eubacteria (Escherichia coli), archaebacteria (Methanococcus halophilus), rat pancreas tissue and rat fibroblasts (cell line RAT1). In all cell types immunoelectron microscopy revealed predominant cytoplasmic location of gold particles, as this could be expected from known biochemical data. In particular, in mammalian cells intensive labeling was observed in cytoplasmic regions rich in polysomes and free ribosomes. At the same time, the label was virtually absent in cytoplasmic regions where microfilament bundles were present. Significant concentrations of gold particles were found in mitochondria and nuclei. In the latter case, gold particles were located over diffuse chromatin regions and were virtually absent over compact chromatin. The density of diffuse chromatin in labeling may amount to about 50% of that found in the cytoplasm. Distribution of labeled antibodies over E. coli cells looks rather similar to that found for M. halophilus: gold particles are preferably concentrated over the cytoplasm and "boundary zone", i.e., a 30 nm wide cytoplasmic zone adjacent to the nucleoid border, while the label over nucleoid is virtually absent. Two main conclusions are drawn: (i) although in the animal cell homogenates WRS is recovered mainly as a soluble cytosolic enzyme, in intact cells it is associated with defined cellular organelles and compartments; this may be an evolutionarily acquired feature probably typical for multicellular organisms; (ii) the considerable density of labeling in diffuse (not compact) chromatin regions may be indicative of WRS involvement in the active chromatin functions (transcription, processing, transfer of gene products, etc.).


Assuntos
Escherichia coli/enzimologia , Fibroblastos/enzimologia , Mathanococcus/enzimologia , Pâncreas/enzimologia , Triptofano-tRNA Ligase/análise , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular , Cromatina/enzimologia , Cromatina/ultraestrutura , Fibroblastos/citologia , Ouro , Microscopia Imunoeletrônica , Mitocôndrias/enzimologia , Mitocôndrias/ultraestrutura , Pâncreas/citologia , Ratos , Ratos Endogâmicos F344
17.
Mutat Res ; 48(3-4): 355-60, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-876271

RESUMO

A prospective cytogenetic study was conducted in 35 workers occupationally exposed to epichlorohydrin (ECHH). Blood samples for cytogenetic analysis were collected before the exposure (to serve as a control) and after the first and second years of ECHH exposure; the cultivation time was 56--58 h. Four slides from each worker were prepared, coded and two of them separately analysed in two collaborating cytogenetic laboratories. About 50 cells were analysed on each slide, giving a total 16,674 scored cells. The percentage of cells with chromosomal aberrations in blood samples of workers was 1.37 before exposure, 1.91 after the first year and 2.69 after the second year of exposure. The difference between percentages of aberrant cells before and after two years of occupational exposure was highly significant (P less than 0.0001). There was particularly observed an increase of chromatid and chomosomal breaks after exposure, simultaneously with an increased number of breaks per 100 cells. These results are concordant with previously reported cytogenetic data found in experiments with mammals and human cells in vitro.


Assuntos
Cloridrinas/farmacologia , Aberrações Cromossômicas , Cromossomos/efeitos dos fármacos , Epicloroidrina/farmacologia , Linfócitos/ultraestrutura , Mutagênicos , Doenças Profissionais/prevenção & controle , Adulto , Exposição Ambiental , Epicloroidrina/administração & dosagem , Humanos , Linfócitos/efeitos dos fármacos , Concentração Máxima Permitida , Pessoa de Meia-Idade
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