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1.
Dis Aquat Organ ; 137(2): 131-144, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31854331

RESUMO

Steller sea lions (SSLs) Eumetopias jubatus experienced a population decline in the 1960s, leading to the listing of the western stock as endangered and the eastern stock as threatened under the US Endangered Species Act. A decrease of births in the western stock beginning in the late 1960s indicates that reproductive failure may have contributed to the decline. We evaluated the role pathogens play in spontaneous abortions, premature births and neonatal deaths in SSLs. Archived tissues from carcasses (n = 19) collected in Alaska from 2002 to 2015 were tested by PCR for Coxiella burnetii, Brucella spp., Chlamydia and morbilliviruses. Animals examined included 47% premature pups, 32% aborted fetuses, 11% neonates and 11% intrauterine fetuses. Gross necropsy and histology findings were summarized in the context of the PCR findings. Tissues were negative for Chlamydia and C. burnetii. Brucella spp. were detected in the lung tissues of 3 animals, including 1 positive for the ST27 strain, the first detection of Brucella spp. DNA in SSLs. Phocine distemper virus was detected in 3 animals in 2 skin lesions and 1 placenta by hemi-nested diagnostic qRT-PCR. Both skin and the placental lesions had vesiculoulcerative changes, and 1 skin lesion contained inclusion bodies in syncytia and upon histologic examination, suggesting that the lesions may be associated with an infection reminiscent of phocine distemper virus, the first in SSLs. We highlight the continuing need for disease surveillance programs to improve our understanding of the prevalence and potential population impacts of these infectious disease agents for pinnipeds in Alaskan waters.


Assuntos
Coxiella burnetii , Leões-Marinhos , Alaska , Animais , Espécies em Perigo de Extinção , Feminino , Gravidez , Inquéritos e Questionários
2.
Geochem Geophys Geosyst ; 22(5): e2020GC009588, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34220359

RESUMO

Increased use and improved methodology of carbonate clumped isotope thermometry has greatly enhanced our ability to interrogate a suite of Earth-system processes. However, interlaboratory discrepancies in quantifying carbonate clumped isotope (Δ47) measurements persist, and their specific sources remain unclear. To address interlaboratory differences, we first provide consensus values from the clumped isotope community for four carbonate standards relative to heated and equilibrated gases with 1,819 individual analyses from 10 laboratories. Then we analyzed the four carbonate standards along with three additional standards, spanning a broad range of δ47 and Δ47 values, for a total of 5,329 analyses on 25 individual mass spectrometers from 22 different laboratories. Treating three of the materials as known standards and the other four as unknowns, we find that the use of carbonate reference materials is a robust method for standardization that yields interlaboratory discrepancies entirely consistent with intralaboratory analytical uncertainties. Carbonate reference materials, along with measurement and data processing practices described herein, provide the carbonate clumped isotope community with a robust approach to achieve interlaboratory agreement as we continue to use and improve this powerful geochemical tool. We propose that carbonate clumped isotope data normalized to the carbonate reference materials described in this publication should be reported as Δ47 (I-CDES) values for Intercarb-Carbon Dioxide Equilibrium Scale.

3.
Nucleic Acids Res ; 35(Database issue): D401-6, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17142235

RESUMO

The PathoSystems Resource Integration Center (PATRIC) is one of eight Bioinformatics Resource Centers (BRCs) funded by the National Institute of Allergy and Infection Diseases (NIAID) to create a data and analysis resource for selected NIAID priority pathogens, specifically proteobacteria of the genera Brucella, Rickettsia and Coxiella, and corona-, calici- and lyssaviruses and viruses associated with hepatitis A and E. The goal of the project is to provide a comprehensive bioinformatics resource for these pathogens, including consistently annotated genome, proteome and metabolic pathway data to facilitate research into counter-measures, including drugs, vaccines and diagnostics. The project's curation strategy has three prongs: 'breadth first' beginning with whole-genome and proteome curation using standardized protocols, a 'targeted' approach addressing the specific needs of researchers and an integrative strategy to leverage high-throughput experimental data (e.g. microarrays, proteomics) and literature. The PATRIC infrastructure consists of a relational database, analytical pipelines and a website which supports browsing, querying, data visualization and the ability to download raw and curated data in standard formats. At present, the site warehouses complete sequences for 17 bacterial and 332 viral genomes. The PATRIC website (https://patric.vbi.vt.edu) will continually grow with the addition of data, analysis and functionality over the course of the project.


Assuntos
Bioterrorismo , Bases de Dados Genéticas , Proteobactérias/genética , Vírus de RNA/genética , Genômica , Internet , Proteobactérias/metabolismo , Proteobactérias/patogenicidade , Proteômica , Vírus de RNA/metabolismo , Vírus de RNA/patogenicidade , Integração de Sistemas , Interface Usuário-Computador
4.
Sci Rep ; 9(1): 15569, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700005

RESUMO

Climate change-driven alterations in Arctic environments can influence habitat availability, species distributions and interactions, and the breeding, foraging, and health of marine mammals. Phocine distemper virus (PDV), which has caused extensive mortality in Atlantic seals, was confirmed in sea otters in the North Pacific Ocean in 2004, raising the question of whether reductions in sea ice could increase contact between Arctic and sub-Arctic marine mammals and lead to viral transmission across the Arctic Ocean. Using data on PDV exposure and infection and animal movement in sympatric seal, sea lion, and sea otter species sampled in the North Pacific Ocean from 2001-2016, we investigated the timing of PDV introduction, risk factors associated with PDV emergence, and patterns of transmission following introduction. We identified widespread exposure to and infection with PDV across the North Pacific Ocean beginning in 2003 with a second peak of PDV exposure and infection in 2009; viral transmission across sympatric marine mammal species; and association of PDV exposure and infection with reductions in Arctic sea ice extent. Peaks of PDV exposure and infection following 2003 may reflect additional viral introductions among the diverse marine mammals in the North Pacific Ocean linked to change in Arctic sea ice extent.


Assuntos
Organismos Aquáticos/virologia , Cetáceos/virologia , Vírus da Cinomose Focina/metabolismo , Cinomose , Aquecimento Global , Gelo , Lontras/virologia , Animais , Regiões Árticas , Cinomose/epidemiologia , Cinomose/transmissão , Vírus da Cinomose Focina/patogenicidade
5.
J Am Coll Cardiol ; 30(7): 1809-12, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9385911

RESUMO

OBJECTIVES: This study sought to determine the rate of familial occurrence of congenital bicuspid aortic valve (BAV) by using echocardiography to screen family members. BACKGROUND: Congenital BAV is a common anomaly that carries with it a significant risk of potential long-term cardiac complications. Despite several reports of the familial occurrence of BAV, the condition is not generally considered to be inherited. METHODS: Thirty consecutive patients with echocardiographically documented congenital BAV were interviewed to construct three-generation family pedigrees. All first-degree relatives were contacted to undergo echocardiography to specifically determine aortic valve morphology. RESULTS: Of the 210 first-degree relatives, 190 (90.5%) agreed to undergo echocardiography. Four members had technically difficult studies. Of the remaining 186 subjects, 17 (9.1%) were identified as having BAV; 11 (36.7%) of the 30 families had at least one additional member with the condition. The male/female ratio of affected members in the 11 families was 1. In one family, two instances of male-to-male transmission were observed. The distribution of BAV in the majority of multiplex families is compatible with autosomal dominant inheritance with reduced penetrance. CONCLUSIONS: We demonstrated a high incidence of familial clustering in congenital BAV. We believe that the high rate of occurrence of the condition in immediate relatives justifies echocardiographic screening of first-degree relatives to anticipate and prevent future complications associated with this common cardiac malformation.


Assuntos
Valva Aórtica/anormalidades , Análise por Conglomerados , Ecocardiografia , Feminino , Genes Dominantes , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/genética , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Linhagem , Fatores de Risco
6.
Arch Intern Med ; 149(10): 2197-200, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2802886

RESUMO

Exercise appears to be capable of exerting a positive effect on bone mass, but how exercise can be used to best advantage in the prevention and therapy of osteopenia is unclear. Weight-bearing activity has been commonly considered to be essential for the beneficial effects of exercise on the skeleton, and, therefore, swimming has been considered valueless in the maintenance of bone mass. To examine this issue we measured radial and vertebral bone mineral density in a group of subjects aged 40 to 85 years who had been swimming regularly for at least 3 years as well as in a similar group of nonexercising control subjects. The swimmers engaged in no other forms of regular exercise, and no subject had other conditions known to affect bone or mineral metabolism. Dietary calcium and protein intakes were similar in the two groups. At both radial (0.84 +/- 0.08 vs 0.81 +/- 0.09 g/cm2) and vertebral (123 +/- 27 vs 108 +/- 31 mg/cm3) sites the male swimmers had significantly greater bone mineral density than did the nonexercisers. In women, however, no relationship of swimming to bone mineral density could be identified. These results suggest that swimming exercise may be beneficial in the prevention or therapy of osteopenia and that its usefulness in this regard should be further investigated.


Assuntos
Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/terapia , Natação , Adulto , Idoso , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cintilografia , Rádio (Anatomia)/diagnóstico por imagem , Caracteres Sexuais , Vértebras Torácicas/diagnóstico por imagem
7.
Neuropsychology ; 15(2): 221-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11324865

RESUMO

The prefrontal cortex has been implicated in the mediation of executive processes that facilitate learning and memory. The authors hypothesized that children with prefrontal dysfunction related to phenylketonuria (PKU) would experience deficits in learning and memory because of impaired strategy use. They evaluated 23 children with PKU and 23 controls by using the California Verbal Learning Test-Children's Version (CVLT-C). General executive abilities were tested using the Stroop Color and Word Test, the Wisconsin Card Sorting Test, and phonemic and category fluency. Children with PKU, especially older children, showed poorer learning across trials and less use of semantic clustering on the CVLT-C but intact retention of previously encoded information. With the exception of phonemic fluency, deficits were not observed in general executive control. Results are discussed within the context of abnormalities in the prefrontal cortex and white matter of the brain.


Assuntos
Transtornos da Memória/fisiopatologia , Fenilcetonúrias/complicações , Córtex Pré-Frontal/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Deficiências da Aprendizagem/diagnóstico , Deficiências da Aprendizagem/etiologia , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Testes Neuropsicológicos , Fonética , Semântica
8.
J Parasitol ; 83(3): 523-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9194839

RESUMO

Fatal hepatic sarcocystosis was diagnosed in 2 polar bears from a zoo in Anchorage, Alaska. Gross lesions were icterus and systemic petechiae. Marked microscopic lesions were detected only in the liver and included severe random necrotizing hepatitis with hemorrhage. Only asexual stages of an apicomplexan parasite were detected within hepatocytes, and rare extracellular zoites were seen in foci of necrosis. The parasite divided by endopolygeny, and occasionally merozoites formed rosettes around a central residual body. Ultrastructural features of the merozoites included a conoid and low numbers of micronemes at the apical pole, centrally located nuclei, and absence of rhoptries. The parasites failed to react with anti-Neospora sp., anti-Toxoplasma gondii, or anti-Sarcocystis neurona sera. The microscopic and ultrastructural morphology of the parasite are most compatible with an apicomplexan protozoan of the genus Sarcocystis. The life cycle of this parasite in bears is not known.


Assuntos
Animais de Zoológico/parasitologia , Hepatopatias Parasitárias/veterinária , Sarcocistose/veterinária , Ursidae/parasitologia , Alaska , Animais , Evolução Fatal , Imuno-Histoquímica , Fígado/parasitologia , Fígado/patologia , Fígado/ultraestrutura , Hepatopatias Parasitárias/patologia , Microscopia Eletrônica/veterinária , Sarcocystis/isolamento & purificação , Sarcocystis/ultraestrutura , Sarcocistose/patologia
9.
Acta Paediatr Suppl ; 407: 75-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7766965

RESUMO

A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.


Assuntos
Aminoácidos/administração & dosagem , Bebidas , Alimentos Formulados , Fenilcetonúrias/dietoterapia , Aminoácidos/sangue , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Humanos , Avaliação Nutricional , Cooperação do Paciente , Fenilalanina/sangue , Fenilcetonúrias/sangue
10.
Appl Ergon ; 27(4): 241-54, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15677065

RESUMO

In this study, a macro-ergonomic risk assessment tool was developed based on criteria of scope, simplicity, practicality, usefulness, reliability and job-specificity. A relative stress index 'RSI' was formulated to take into account multiple parameters, such as frequency, duration, repetition, weight, force, travel distance and horizontal distance. This tool was tested in nuclear remediation industry. The results are presented and discussed.

11.
Practitioner ; 216(1295): 519-28, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-951388

RESUMO

To put a patient at ease is always important, but this is especially so when making an examination following a sexual offence. The place of examination is important. The choice can be a police station, a hospital or your own consulting-room. If at all possible, your own consulting-room is best. Always explain exactly what you are doing and for what reason. This is reassuring to the patient. Take the specimens systematically. Number and label them carefully before handing them over to the police officer. Notes taken at the time of your examination can be used when giving evidence in court. Therefore legible notes are invaluable. I have also found it useful to have a photostat of my statement as a witness. The police will provide this on request. Note-taking is particularly important in cases in which there are special difficulties. Examinations following sexual assault involve attending court to give evidence. By no means all the examinations made will lead to court cases. Often the accused cannot be found, sometimes the woman drops the allegation, or the Director of Public Prosecutions does not recommend the case to come for trial. Since the Criminal Justice Act 1967 it has been possible in all criminal proceedings to admit a written statement as evidence just as if it had been given orally. This statement must be signed by the witness, who will be liable to prosecution if he has stated in it anything that he knew to be false or did not believe to be true. A copy is served on the opposing side and if they make no objection it can be used by the defence in evidence. In other words, your presence in court is necessary only if some point needs to be made clear by cross-examination. I should like to see long-term follow up of rape victims. At present there is none that I know of, but at least some immediate reassurance and explanation can be given to the patient, together with treatment and recommendations for further care if necessary.


Assuntos
Medicina Legal , Delitos Sexuais , Aborto Criminoso , Adolescente , Adulto , Idoso , Criança , Feminino , Ginecologia , Cabelo/análise , Humanos , Incesto , Infanticídio , Legislação como Assunto , Masculino , Pessoa de Meia-Idade , Unhas/análise , Transtornos Parafílicos , Exame Físico , Gravidez , Estupro , Sêmen/análise , Manejo de Espécimes , Reino Unido
12.
J Mass Spectrom ; 44(9): 1318-29, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19621330

RESUMO

The geochemistry of multiply substituted isotopologues ('clumped-isotope' geochemistry) examines the abundances in natural materials of molecules, formula units or moieties that contain more than one rare isotope (e.g. (13)C(18)O(16)O, (18)O(18)O, (15)N(2), (13)C(18)O(16)O(2) (2-)). Such species form the basis of carbonate clumped-isotope thermometry and undergo distinctive fractionations during a variety of natural processes, but initial reports have provided few details of their analysis. In this study, we present detailed data and arguments regarding the theoretical and practical limits of precision, methods of standardization, instrument linearity and related issues for clumped-isotope analysis by dual-inlet gas-source isotope ratio mass spectrometry (IRMS). We demonstrate long-term stability and subtenth per mil precision in 47/44 ratios for counting systems consisting of a Faraday cup registered through a 10(12) ohm resistor on three Thermo-Finnigan 253 IRMS systems. Based on the analyses of heated CO(2) gases, which have a stochastic distribution of isotopes among possible isotopologues, we document and correct for (1) isotopic exchange among analyte CO(2) molecules and (2) subtle nonlinearity in the relationship between actual and measured 47/44 ratios. External precisions of approximately 0.01 per thousand are routinely achieved for measurements of the mass-47 anomaly (a measure mostly of the abundance anomaly of (13)C-(18)O bonds) and follow counting statistics. The present technical limit to precision intrinsic to our methods and instrumentation is approximately 5 parts per million (ppm), whereas precisions of measurements of heterogeneous natural materials are more typically approximately 10 ppm (both 1 s.e.). These correspond to errors in carbonate clumped-isotope thermometry of +/-1.2 degrees C and +/-2.4 degrees C, respectively.

13.
Br Med J ; 280(6228): 1377, 1980 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-6446348

RESUMO

PIP: For more than 20 years a large proportion of time has been given to providing birth control advice. Through the years there have always been a minority of patients opting for female sterilization, more since laparoscopic sterilization became available. The advantages of quicker recovery and shorter hospital stays to the busy mother whose family is complete are obvious. In the last 3 years more gynecologists have been using plastic and silicone clips and rings. In your leading article (12 April, p. 1037) you quote similar pregnancy rates. In my practice the only failures have been when tubes were occluded by clips. I would like to put in a plea for still using laparoscopic sterilizaton with cautery with women who are unlike to change their minds. In this category I would consider particularly those women who are happily married and whose children are now adolescents. An added factor is that the women may be unsuitable for having more children. In these patients the situation can be even more difficult because they feel quite unable to accept a termination of pregnancy should contraception fail. Both husband and wife should understand the procedure, and should make their decision knowing that it is irreversible and that repair of the tubes does not often lead to a successful pregnancy. The type of sterilization should be tailored to the individual patient.^ieng


Assuntos
Esterilização Tubária , Feminino , Humanos , Laparoscopia , Reversão da Esterilização
14.
Biochemistry ; 39(15): 4543-51, 2000 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-10758004

RESUMO

Peptide deformylase catalyzes the removal of the N-terminal formyl group from newly synthesized polypeptides in eubacteria. Its essential character in bacterial cells makes it an attractive target for antibacterial drug design. In this work, we have rationally designed and synthesized a series of peptide thiols that act as potent, reversible inhibitors of purified recombinant peptide deformylase from Escherichia coli and Bacillus subtilis. The most potent inhibitor has a K(I) value of 11 nM toward the B. subtilis enzyme. These inhibitors showed antibacterial activity against both Gram-positive and Gram-negative bacteria, with minimal inhibitory concentrations (MIC) as low as 5 microM ( approximately 2 microg/mL). The PDF inhibitors induce bacterial cell lysis and are bactericidal toward all four bacterial strains that have been tested, B. subtilis, Staphylococcus epidermidis, Enterococcus faecalis, and E. coli. Resistance evaluation of one of the inhibitors (1b) against B. subtilis showed that no resistant clone could be found from >1 x 10(9) cells. Quantitative analysis using a set of inhibitors designed to possess varying potencies against the deformylase enzyme revealed a linear correlation between the MIC values and the K(I) values. These results suggest that peptide deformylase is the likely molecular target responsible for the antibacterial activity of these inhibitors and is therefore a viable target for antibacterial drug design.


Assuntos
Amidoidrolases , Aminopeptidases/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Aminopeptidases/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Bacillus subtilis/citologia , Bacillus subtilis/enzimologia , Bacteriólise/efeitos dos fármacos , Ligação Competitiva , Divisão Celular/efeitos dos fármacos , Quelantes/síntese química , Quelantes/química , Quelantes/metabolismo , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Desenho de Fármacos , Resistência Microbiana a Medicamentos , Enterococcus faecalis/citologia , Enterococcus faecalis/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Escherichia coli/citologia , Escherichia coli/enzimologia , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Peptídeos/síntese química , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Staphylococcus epidermidis/citologia , Staphylococcus epidermidis/efeitos dos fármacos , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo , Compostos de Sulfidrila/farmacologia , Termodinâmica
15.
Br J Obstet Gynaecol ; 84(10): 784-8, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-336078

RESUMO

A placebo-controlled, randomized, double-blind, parallel group study in hospital and general practice has shown that a combination of belladonna alkaloids, ergotamine tartrate, and phenobarbitone (Bellergal) was effective in treating troublesome symptoms of the premenstrual syndrome of which fatigue, tender breasts, nervousness, irritability, lethargy and listlessness were improved to a statistically significant degree. The drug was given three times daily and caused no side effects.


Assuntos
Alcaloides de Belladona/uso terapêutico , Ergotamina/uso terapêutico , Fenobarbital/uso terapêutico , Síndrome Pré-Menstrual/tratamento farmacológico , Adolescente , Adulto , Ensaios Clínicos como Assunto , Combinação de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade
16.
J Comb Chem ; 2(6): 650-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11126293

RESUMO

Peptide deformylase catalyzes the removal of the N-terminal formyl group from nascent polypeptides during prokaryotic protein synthesis and maturation and is essential for bacterial survival. Its apparent absence from mammalian organisms makes it an attractive target for designing novel antibacterial agents. Based on the substrate specificity of peptide deformylase from Escherichia coli, a focused library of peptide thiols was synthesized on TentaGel resin using a disulfide linkage. Screening of the library against the purified deformylase was carried out in solution phase after the inhibitors were released from the resin with a reducing agent. A potent deformylase inhibitor was obtained from a 750-member library and was further optimized through rational modification into a low nanomolar inhibitor (KI = 15 nM against E. coli deformylase).


Assuntos
Amidoidrolases , Aminopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/química , Técnicas de Química Combinatória , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
17.
J Cardiovasc Pharmacol ; 31 Suppl 1: S424-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9595502

RESUMO

The canine model of pacing-induced heart failure (HF) simulates human dilated cardiomyopathy and is characterized by severe hemodynamic perturbations. We have previously demonstrated increased plasma endothelin-1 (ET-1) and left ventricular (LV) tissue peptide levels in this model. However, the gene expression of ET-1 has not been studied. Accordingly, we compared preproET-1 mRNA in the lungs and LV in control normal dogs, dogs with severe HF after 3 weeks of rapid pacing (pHF), and pHF dogs chronically treated with an ETA antagonist, LU135252 (pHF-LU). PreproET-1 mRNA expression was determined by ribonuclease protection assay and quantified by densitometry. In paced dogs, mean pulmonary artery pressure (PA) and LV end-diastolic pressure (LVEDP) increased markedly from 16 +/- 4 and 8 +/- 3 mm Hg, respectively, at baseline to 40 +/- 11 and 34 +/- 7 mm Hg, respectively, at 3 weeks (both p < 0.001). Treatment with LU135252 attenuated the increase in PA and LVEDP by 30% and 19%, respectively (p < 0.05 for both). Compared to controls, preproET-1 mRNA expression in the LV and lungs was markedly increased in pHF. This was not changed in the LV but was reduced in the lungs by treatment with the ETA antagonist. Increased pulmonary and LV expression of preproET-1 suggests that ET-1 plays a role in mediating the pulmonary hypertension and LV dysfunction characteristic of this model.


Assuntos
Endotelinas/biossíntese , Insuficiência Cardíaca/metabolismo , Pulmão/metabolismo , Miocárdio/metabolismo , Precursores de Proteínas/biossíntese , RNA Mensageiro/biossíntese , Animais , Estimulação Cardíaca Artificial , Cães , Antagonistas dos Receptores de Endotelina , Endotelina-1 , Endotelinas/genética , Expressão Gênica/fisiologia , Humanos , Masculino , Fenilpropionatos/farmacologia , Precursores de Proteínas/genética , Pirimidinas/farmacologia , RNA Mensageiro/genética , Receptor de Endotelina A , Ribonucleases/metabolismo
18.
Biochemistry ; 38(47): 15587-96, 1999 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-10569943

RESUMO

Peptide-derived thiols of the general structure N-mercaptoacyl-leucyl-p-nitroanilide (1a-c) were synthesized and found to be potent, slow-binding inhibitors of the aminopeptidase from Aeromonas proteolytica (AAP). The overall potencies (K(I)) of these inhibitors against AAP range from 2.5 to 57 nM exceeding that of the natural product bestatin and approaching that of amastatin. The corresponding alcohols (2a-b) are simple competitive inhibitors of much lower potencies (K(I) = 23 and 360 microM). These data suggest that the free thiols are involved in the formation of the E. I and E.I complexes, presumably serving as a metal ligand. To investigate the nature of the interaction of the thiol-based inhibitors with the dinuclear active site of AAP, we have recorded electronic absorption and EPR spectra of Co(II)Co(II)-, Co(II)Zn(II)-, and Zn(II)Co(II)-AAP in the presence of the strongest binding inhibitor, 1c. Both [CoZn(AAP)] and [ZnCo(AAP)], in the presence of 1c, exhibited an absorption band centered at 320 nm characteristic of an S --> Co(II) ligand-metal charge-transfer band. In addition, absorption spectra recorded between 400 and 700 nm showed changes characteristic of 1c interacting with each active-site metal ion. EPR spectra recorded at high temperature (19 K) and low power (2.5 mW) indicated that in a given enzyme molecule, 1c interacts weakly with one of the metal ions in the dinuclear site and that the crystallographically identified micro-OH(H) bridge, which has been shown to mediate electronic interaction of the Co(II) ions, is likely broken upon 1c binding. EPR spectra of [CoCo(AAP)]-1c, [ZnCo(AAP)]-1c, and [CoZn(AAP)]-1c were also recorded at lower temperature (3.5-4.0 K) and high microwave power (50-553 mW). The observed signals were unusual and appeared to contain, in addition to the incompletely saturated contributions from the signals characterized at 19 K, a very sharp feature at g(eff) approximately 6.8 that is characteristic of thiolate-Co(II) interactions. These data suggest that the thiolate moiety can bind to either of the metal ions in the dinuclear active site of AAP but does not bridge the dinuclear cluster. Compounds 1a-c are readily accessible by synthesis and thus provide a novel class of potent aminopeptidase inhibitors.


Assuntos
Aeromonas/enzimologia , Aminopeptidases/antagonistas & inibidores , Proteínas de Bactérias , Dipeptídeos/síntese química , Inibidores Enzimáticos/síntese química , Peptídeos/síntese química , Compostos de Sulfidrila/síntese química , Aminopeptidases/química , Ligação Competitiva , Cobalto/química , Dipeptídeos/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Inibidores Enzimáticos/farmacologia , Cinética , Leucina/química , Leucina/farmacologia , Metaloproteínas/química , Peptídeos/farmacologia , Espectrofotometria , Compostos de Sulfidrila/farmacologia , Zinco/química
19.
N Engl J Med ; 344(15): 1132-8, 2001 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-11297704

RESUMO

BACKGROUND: The frequency of major malformations, growth retardation, and hypoplasia of the midface and fingers, known as the anticonvulsant embryopathy, is increased in infants exposed to anticonvulsant drugs in utero. However, whether the abnormalities are caused by the maternal epilepsy itself or by exposure to anticonvulsant drugs is not known. METHODS: We screened 128,049 pregnant women at delivery to identify three groups of infants: those exposed to anticonvulsant drugs, those unexposed to anticonvulsant drugs but with a maternal history of seizures, and those unexposed to anticonvulsant drugs with no maternal history of seizures (control group). The infants were examined systematically for the presence of major malformations, signs of hypoplasia of the midface and fingers, microcephaly, and small body size. RESULTS: The combined frequency of anticonvulsant embryopathy was higher in 223 infants exposed to one anticonvulsant drug than in 508 control infants (20.6 percent vs. 8.5 percent; odds ratio, 2.8; 95 percent confidence interval, 1.1 to 9.7). The frequency was also higher in 93 infants exposed to two or more anticonvulsant drugs than in the controls (28.0 percent vs. 8.5 percent; odds ratio, 4.2; 95 percent confidence interval, 1.1 to 5.1). The 98 infants whose mothers had a history of epilepsy but took no anticonvulsant drugs during the pregnancy did not have a higher frequency of those abnormalities than the control infants. CONCLUSIONS: A distinctive pattern of physical abnormalities in infants of mothers with epilepsy is associated with the use of anticonvulsant drugs during pregnancy, rather than with epilepsy itself.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Anticonvulsivantes/efeitos adversos , Epilepsia/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Anormalidades Induzidas por Medicamentos/epidemiologia , Carbamazepina/efeitos adversos , Estudos de Casos e Controles , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/etiologia , Face/anormalidades , Feminino , Retardo do Crescimento Fetal/induzido quimicamente , Dedos/anormalidades , Humanos , Recém-Nascido , Modelos Logísticos , Fenobarbital/efeitos adversos , Fenitoína/efeitos adversos , Gravidez , Ácido Valproico/efeitos adversos
20.
J Pediatr ; 133(3): 346-52, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9738714

RESUMO

OBJECTIVE: To examine the efficacy of a combination of 4 blood markers of alcohol use in detecting alcohol-abusing pregnant women. STUDY DESIGN: Two new markers of alcohol use, whole blood-associated acetaldehyde and carbohydrate-deficient transferrin, and 2 traditional markers of alcohol use, gamma-glutamyl transpeptidase and mean red blood cell volume, were measured in the blood of pregnant women. Each woman was interviewed about alcohol and drug use, medical and obstetric histories, and nutrition. Each infant was examined by a clinician who was blinded to exposure status. RESULTS: All of the women who reported drinking an average of 1 or more ounces of absolute alcohol per day had at least 1 positive blood marker. The infants of mothers with 2 or more positive markers had significantly smaller birth weights, lengths, and head circumferences than the infants with negative maternal screens. The presence of 2 or more positive markers was more predictive of infant outcome than any self-reporting measure. CONCLUSIONS: These markers, which detect more at-risk pregnant women than self-reporting methods, could lead to better efforts at detection and prevention of alcohol-induced fetal damage.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Etanol/intoxicação , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Gravidez/sangue , Diagnóstico Pré-Natal , Efeitos Tardios da Exposição Pré-Natal , Acetaldeído/sangue , Adulto , Biomarcadores/sangue , Peso ao Nascer , Estatura , Índices de Eritrócitos , Etanol/efeitos adversos , Feminino , Transtornos do Espectro Alcoólico Fetal/prevenção & controle , Cabeça/anatomia & histologia , Humanos , Recém-Nascido , Anamnese , Fenômenos Fisiológicos da Nutrição , Valor Preditivo dos Testes , Resultado da Gravidez , História Reprodutiva , Método Simples-Cego , Transtornos Relacionados ao Uso de Substâncias/sangue , Transferrina/análise , gama-Glutamiltransferase/sangue
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