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1.
Mamm Genome ; 33(1): 66-80, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34741192

RESUMO

Model organism research is essential for discovering the mechanisms of human diseases by defining biologically meaningful gene to disease relationships. The Rat Genome Database (RGD, ( https://rgd.mcw.edu )) is a cross-species knowledgebase and the premier online resource for rat genetic and physiologic data. This rich resource is enhanced by the inclusion and integration of comparative data for human and mouse, as well as other human disease models including chinchilla, dog, bonobo, pig, 13-lined ground squirrel, green monkey, and naked mole-rat. Functional information has been added to records via the assignment of annotations based on sequence similarity to human, rat, and mouse genes. RGD has also imported well-supported cross-species data from external resources. To enable use of these data, RGD has developed a robust infrastructure of standardized ontologies, data formats, and disease- and species-centric portals, complemented with a suite of innovative tools for discovery and analysis. Using examples of single-gene and polygenic human diseases, we illustrate how data from multiple species can help to identify or confirm a gene as involved in a disease and to identify model organisms that can be studied to understand the pathophysiology of a gene or pathway. The ultimate aim of this report is to demonstrate the utility of RGD not only as the core resource for the rat research community but also as a source of bioinformatic tools to support a wider audience, empowering the search for appropriate models for human afflictions.


Assuntos
Pesquisa Biomédica , Bases de Dados Genéticas , Animais , Chlorocebus aethiops , Cães , Genoma/genética , Genômica , Camundongos , Oligopeptídeos , Suínos
2.
Dentomaxillofac Radiol ; 40(6): 362-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21831976

RESUMO

OBJECTIVES: The assessment of image quality is a crucial step in the development of a new imaging protocol. Having proposed and reported on a preliminary protocol for sialography using cone beam CT (CBCT), the purpose of this study was to further optimize this protocol by maximizing the image signal difference-to-noise ratio (SDNR) and to relate these new data to previously published dosimetric data for CBCT sialography. METHODS: An imaging phantom was constructed using samples with different concentrations of iodine and a water-immersed mandible. The CB MercuRay (Hitachi Medical Systems, Tokyo, Japan) was used to image the phantom using different peak kilovoltage (kVp) and milliamperage (mA) settings. SDNR was then calculated using the raw images based on mean pixel values (MPV) measured in selected regions of interest (ROI). Finally, a figure of merit (FOM) was calculated to examine the trade-off between image SDNR and effective radiation dose. RESULTS: The SDNR demonstrated an expected increase as the kVp increased from 60 to 120. Also, images made with the higher mA setting (15) had greater SDNR. The iodine concentration also influenced the image quality such that SDNR increased with increased amounts of iodine. The calculated FOM was greatest for the technique using 80 kVp, with equivalent results for 10 mA and 15 mA. CONCLUSION: An optimized protocol for CBCT sialography using CB MercuRay entails a 6 inch field of view with 80 kVp and 10 mA.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Sialografia/métodos , Artefatos , Cadáver , Meios de Contraste , Humanos , Iodo , Mandíbula/diagnóstico por imagem , Imagens de Fantasmas , Radiometria
3.
J Perinatol ; 30(7): 469-73, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20010613

RESUMO

OBJECTIVE: Our aim was to evaluate the safety of a silver-alginate-containing dressing to reduce peripherally inserted central catheter (PICC) infections in neonatal intensive care unit (NICU) patients. STUDY DESIGN: Patients were randomized 3:1 to receive a patch containing silver, alginate and maltodextrin or standard of care. Patches were placed under the regular transparent retention dressing at the PICC exit site at insertion and were replaced with every dressing change at least every 2 weeks until PICC discontinuation. All study infants were monitored for adverse skin reactions. RESULT: A total of 100 infants were followed up for 1922 person-days, including 75 subjects with 89 PICCs who received the patch. The median birth weight (1330 g) and median gestational age (30 weeks) was lower in the patch group when compared with the controls (P=0.001 and 0.005, respectively). Study patients received the patch with their PICC at a median age of 5 days; the patch stayed in place for a median of 13 days. We noted no adverse skin reactions and found no evidence that the patch alters the microbiology of PICC-associated infections. CONCLUSION: This pilot trial suggests that silver-alginate-coated dressings are skin safe and their inclusion in future trials aimed at reduction of PICC-associated bloodstream infections in the NICU should be considered.


Assuntos
Antibacterianos/administração & dosagem , Bandagens , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Sepse/prevenção & controle , Administração Cutânea , Alginatos/administração & dosagem , Feminino , Ácido Glucurônico/administração & dosagem , Ácidos Hexurônicos/administração & dosagem , Humanos , Recém-Nascido , Masculino , Projetos Piloto , Polissacarídeos/administração & dosagem , Prata/administração & dosagem , Resultado do Tratamento
4.
Folia Morphol (Warsz) ; 65(2): 178-80, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16773612

RESUMO

During routine cadaveric dissection of the upper extremity an unusual muscle was discovered arising from the tendon of the flexor carpi ulnaris and inserting into the muscle belly of the flexor digiti minimi. The muscle's course was superficial to the ulnar nerve and artery in Guyon's canal. We review the literature regarding such muscle variations and discuss the potential for compression of the ulnar nerve by such muscles.


Assuntos
Músculo Esquelético/anormalidades , Síndromes de Compressão do Nervo Ulnar/etiologia , Nervo Ulnar/patologia , Punho/patologia , Idoso , Humanos , Masculino , Músculo Esquelético/inervação
5.
Mol Cell ; 7(4): 741-51, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11336698

RESUMO

Chromatin remodeling complexes perform central roles in transcriptional regulation. Here, we identify Rsc3 and Rsc30 as novel components of the essential yeast remodeler RSC complex. Rsc3 and Rsc30 function requires their zinc cluster domain, a known site-specific DNA binding motif. RSC3 is essential, and rsc3 Ts- mutants display a G2/M cell cycle arrest involving the spindle assembly checkpoint pathway, whereas rsc30Delta mutants are viable and osmosensitive. Rsc3 and Rsc30 interact functionally and also physically as a stable Rsc3/Rsc30 heteromeric complex. However, DNA microarray analysis with rsc3 or rsc30 mutants reveals different effects on the expression levels of ribosomal protein genes and cell wall genes. We propose that Rsc3 and Rsc30 interact physically but have different roles in targeting or regulating RSC.


Assuntos
Cromatina/metabolismo , Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica , Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição/genética , Zinco/metabolismo , Sequência de Bases , Ciclo Celular/genética , Parede Celular/fisiologia , Cromatina/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Dimerização , Fase G2/genética , Genes Letais/fisiologia , Genes cdc/fisiologia , Zíper de Leucina/fisiologia , Mitose/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Nucleares/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Fuso Acromático/genética , Fuso Acromático/metabolismo , Temperatura , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Leveduras , Zinco/química
6.
Pain ; 89(2-3): 111-5, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11166466

RESUMO

Patients with fibromyalgia syndrome (FS) experience a decreased ability to participate in both vocational and avocational activities. Although many treatment programs advocate activity pacing techniques, 'pacing' is a poorly understood concept for which there are no available measures. The present study describes a brief six-item pacing scale that can be administered as part of the Chronic Pain Coping Inventory (CPCI). Preliminary data indicate that this scale is a valid, reliable index of the pacing construct that is associated with physical impairment in patients with FS and is unrelated to simple task persistence.


Assuntos
Fibromialgia/psicologia , Dor/psicologia , Adaptação Psicológica , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Análise de Regressão , Inquéritos e Questionários
7.
J Mol Biol ; 294(5): 1311-25, 1999 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-10600387

RESUMO

We report the crystal structure of the yeast protein Hpa2 in complex with acetyl coenzyme A (AcCoA) at 2.4 A resolution and without cofactor at 2.9 A resolution. Hpa2 is a member of the Gcn5-related N-acetyltransferase (GNAT) superfamily, a family of enzymes with diverse substrates including histones, other proteins, arylalkylamines and aminoglycosides. In vitro, Hpa2 is able to acetylate specific lysine residues of histones H3 and H4 with a preference for Lys14 of histone H3. Hpa2 forms a stable dimer in solution and forms a tetramer upon binding AcCoA. The crystal structure reveals that the Hpa2 tetramer is stabilized by base-pair interactions between the adenine moieties of the bound AcCoA molecules. These base-pairs represent a novel method of stabilizing an oligomeric protein structure. Comparison of the structure of Hpa2 with those of other GNAT superfamily members illustrates a remarkably conserved fold of the catalytic domain of the GNAT family even though members of this family share low levels of sequence homology. This comparison has allowed us to better define the borders of the four sequence motifs that characterize the GNAT family, including a motif that is not discernable in histone acetyltransferases by sequence comparison alone. We discuss implications of the Hpa2 structure for the catalytic mechanism of the GNAT enzymes and the opportunity for multiple histone tail modification created by the tetrameric Hpa2 structure.


Assuntos
Acetiltransferases/química , Proteínas de Ligação a DNA , Proteínas Fúngicas/química , Família Multigênica , Proteínas Quinases/química , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimologia , Acetilcoenzima A/química , Acetilcoenzima A/metabolismo , Acetilação , Acetiltransferases/metabolismo , Adenina/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Pareamento de Bases , Sítios de Ligação , Domínio Catalítico , Sequência Conservada , Cristalização , Cristalografia por Raios X , Dimerização , Proteínas Fúngicas/metabolismo , Histona Acetiltransferases , Histonas/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Dobramento de Proteína , Proteínas Quinases/metabolismo , Estrutura Quaternária de Proteína , Relação Estrutura-Atividade
8.
J Pediatr ; 135(4): 423-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10518075

RESUMO

OBJECTIVES: To determine morphine pharmacokinetics in premature neonates varying in postconceptional age (PCA) and evaluate behavioral pain response in relationship to serum morphine concentrations. METHODS: Premature neonates (n = 48), stratified by weeks of PCA (group 1 = 24-27 weeks, group 2 = 28-31 weeks, group 3 = 32-35 weeks, and group 4 = 36-39 weeks) received morphine infusions. Blood samples were drawn at 48, 60, and 72 hours and at discontinuation of morphine, followed by 3 samples obtained during the next 24 hours. Newborns were videotaped during heel lances and restful states, with morphine at steady-state concentrations and without morphine. Pain was assessed by using the Neonatal Facial Coding System (NFCS). Statistical analysis included regression between NFCS score changes from baseline to painful procedure with and without morphine. RESULTS: Morphine clearance for groups 1, 2, 3, and 4 was calculated as 2.27 +/- 1.07, 3.21 +/- 1.57, 4.51 +/- 1.97, and 7.80 +/- 2.67 mL/kg/min, respectively, and correlated with PCA (r = 0.63, P <.001). Pain measured by facial expression was diminished; however, it did not correlate with morphine concentrations. CONCLUSION: Morphine clearance in premature neonates is less than reported, increasing with PCA. Facial activity discloses morphine analgesia; however, it is unrelated to morphine concentrations.


Assuntos
Analgésicos Opioides/farmacocinética , Recém-Nascido Prematuro/metabolismo , Morfina/farmacocinética , Medição da Dor , Cromatografia Líquida de Alta Pressão , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro/fisiologia , Masculino
9.
Mol Microbiol ; 28(6): 1121-37, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9680203

RESUMO

The expression of Pap pili that facilitate the attachment of Escherichia coli to uroepithelial cells is shut off outside the host at temperatures below 26 degrees C. Ribonuclease protection analysis showed that this thermoregulatory response was rapid as evidenced by the absence of papBA transcripts, coding for Pap pilin, after only one generation of growth at 23 degrees C. The histone-like nucleoid structuring protein H-NS and DNA sequences within papB were required for thermoregulation, but the PapB and PapI regulatory proteins were not. In vivo analysis of pap DNA methylation patterns indicated that H-NS or a factor regulated by H-NS bound within the pap regulatory region at 23 degrees C but not at 37 degrees C, as evidenced by H-NS-dependent inhibition of methylation of the pap GATC sites designated GATC-I and GATC-II. These GATC sites lie upstream of the papBAp promoter and have been shown previously to play a role in controlling Pap pili expression by regulating the binding of Lrp, a global regulator that is essential for activating papBAp transcription. Competitive electrophoretic mobility shift analysis showed that H-NS bound specifically to a pap DNA fragment containing the GATC-I and GATC-II sites. Moreover, H-NS blocked methylation of these pap GATC sites in vitro: H-NS blocked pap GATC methylation at 1.4 microM but was unable to do so at higher concentrations at which non-specific binding occurred. Thus, non-specific binding of H-NS to pap DNA was not sufficient to inhibit methylation of the pap GATC sites. These results suggest that the ability of H-NS to act as a methylation blocking factor is dependent upon the formation of a specific complex of H-NS with pap regulatory DNA. We hypothesize that a function of H-NS such as oligomerization was altered at 23 degrees C, which enabled H-NS to repress pap gene expression through the formation of a specific nucleoprotein complex.


Assuntos
Proteínas de Bactérias , Proteínas de Ligação a DNA/genética , Escherichia coli/genética , Fímbrias Bacterianas/genética , Regulação Bacteriana da Expressão Gênica , Transcrição Gênica/genética , Fusão Gênica Artificial , Colífagos/genética , Metilação de DNA , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/crescimento & desenvolvimento , Fímbrias Bacterianas/metabolismo , Óperon Lac , Mutação , Óperon , Plasmídeos/genética , RNA Mensageiro/metabolismo , Temperatura , beta-Galactosidase/metabolismo
10.
Arch Virol ; 142(5): 1045-50, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9191869

RESUMO

An H1N7 influenza A virus, isolated from pigs in England in 1992, was examined genetically to determine the characteristics and probable origin of the eight gene segments. Six of the RNA segments encoding PB2, PB1, PA, HA, NP and NS were related most closely to those of human viruses, whilst two of the RNA segments (NA and M) were related most closely to those of equine viruses. The HA gene was most similar to that of A/USSR/90/77 (H1N1) but amino acid differences suggested independent genetic drift. In contrast, there were relatively few changes in the NA and M genes compared to those of A/equine/Prague/1/56 (H7N7).


Assuntos
Vírus da Influenza A/genética , Suínos/virologia , Animais , Inglaterra , Dados de Sequência Molecular , RNA Viral , Homologia de Sequência do Ácido Nucleico
12.
J Mol Cell Cardiol ; 28(1): 103-12, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8745218

RESUMO

The mitochondrial ATPase enzyme accounts for roughly 35-50% of the overall energy demand that leads to ATP depletion under conditions of severe myocardial ischemia. In larger mammalian hearts, this energy squandering action of the ATPase is modulated by an endogenous inhibitor protein. The present studies were undertaken to characterize the time course of inhibition of the mitochondrial ATPase in canine myocardium under conditions of severe regional ischemia in vivo. In addition, we determined if the energy sparing effects of ischemic preconditioning (PC) can be explained by persistent inhibition of the mitochondrial ATPase enzyme. The circumflex coronary artery was ligated for 1.5 min (n = 4), 5 min (n = 6), or 15 min (n = 5). In a separate group (n = 7), hearts were preconditioned by four 5-min periods of ischemia each followed by 5 min of reperfusion. Sub-mitochondrial particles were prepared from the sub-endocardial zone of the ischemic and non-ischemic regions and were assayed for oligomycin-sensitive ATPase activity. ATPase activity was reduced to about 79% at 1.5 min and to approximately 55% at 5 and 15 min of ischemia, relative to non-ischemic tissue from the same heart. The rate of HEP utilization slowed concurrently with the development of ATPase inhibition. In preconditioned myocardium, ATPase activity was not significantly different from control myocardium from the same heart. We conclude that the early inhibition of the mitochondrial ATPase activity slows the utilization of high energy phosphate and thereby serves as an important endogenous cardioprotective mechanism. Nevertheless, altered activity of the ATPase is not the explanation of the energy sparing effect of ischemic preconditioning.


Assuntos
Adenosina Trifosfatases/metabolismo , Mitocôndrias Cardíacas/enzimologia , Isquemia Miocárdica/enzimologia , Partículas Submitocôndricas/enzimologia , Difosfato de Adenosina/metabolismo , Adenosina Trifosfatases/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Animais , Fracionamento Celular , Circulação Coronária , Vasos Coronários/fisiologia , Cães , Metabolismo Energético , Cinética , Microscopia Eletrônica de Varredura , Mitocôndrias Cardíacas/ultraestrutura , Miocárdio/metabolismo , Oligomicinas/farmacologia , Fosfocreatina/metabolismo , Valores de Referência , Fluxo Sanguíneo Regional , Partículas Submitocôndricas/ultraestrutura , Fatores de Tempo
13.
Cancer Res ; 55(14): 3140-8, 1995 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7606735

RESUMO

Despite molecular biological advances in understanding human cancers, translation into therapy has been less forthcoming; targeting neoplastic cells still requires that tumor-specific markers, preferably those on the cell surface, be identified. The epidermal growth factor receptor (EGFR) exists in a deletion-mutant form, EGFRvIII, which has been identified by genetic and immunological means in a subset of gliomas and non-small cell lung carcinomas. Specific polyvalent antisera to the extracellular portion of the variant were readily induced, but immunization using a synthetic linear peptide representing the unique EGFRvIII primary sequence has been unsuccessful in mice or macaques. We report here five specific monoclonal antibodies (mAbs) developed through long-term immunization protocols using the EGFRvIII-specific synthetic peptide and the intact variant in different formats that maintained secondary and tertiary conformation. These mAbs identify the EGFRvIII on the cell surface with relatively high affinity (KA range, 0.13 to 2.5 x 10(9) M-1) by live cell Scatchard analysis. These mAbs are specific for EGFRvIII as determined by RIA, ELISA, Western blot, analytical flow cytometry, autophosphorylation, and immunohistochemistry. Isolating specific mAbs enabled us to analyze normal and neoplastic human tissue and establish that EGFRvIII is truly tumor specific for subsets of breast carcinomas and for previously reported non-small cell lung carcinomas and gliomas. Also, this receptor is not expressed by any normal human tissues thus far examined, including elements of the peripheral, central nervous, and lymphoid systems. With mAbs, we identified a higher incidence of EGFRvIII positivity in gliomas than previously described and identified an EGFRvIII-positive subset of breast tumors; also, we observed that the EGFRvIII epitope is not expressed in normal tissues, and we demonstrated the localizing and therapeutic potential of the mAbs for tumors expressing this epitope. Our observations strongly warrant development of this mAb-antigen system as therapy for breast, lung, and central nervous system tumors.


Assuntos
Anticorpos Monoclonais/imunologia , Neoplasias da Mama/ultraestrutura , Receptores ErbB/imunologia , Glioma/ultraestrutura , Neoplasias Pulmonares/ultraestrutura , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Especificidade de Anticorpos , Sequência de Bases , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Receptores ErbB/classificação , Receptores ErbB/genética , Feminino , Glioma/imunologia , Glioma/metabolismo , Humanos , Imuno-Histoquímica , Cinética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Transplante de Neoplasias , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/genética , Transcrição Gênica , Transplante Heterólogo , Células Tumorais Cultivadas
14.
Ann Thorac Surg ; 59(4): 825-7; discussion 827-8, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7695404

RESUMO

The treatment of asymptomatic patients with small pneumothoraces (ie, less than 20% by volume) has included observation, tube thoracostomy, and operation. When observation is used, the anticipated expansion of the lung has been estimated to be 1.25% of the lung volume daily. This study was designed to evaluate the use of inhaled oxygen as a method to accelerate the resolution of a pneumothorax in a rabbit model. Experimental pneumothoraces were created in 23 white New Zealand rabbits. Group 1 (9 rabbits) were placed in a cage with room air and group 2 (11 rabbits) were placed in a cage with high oxygen concentration. Three rabbits died before completion of the study. Serial chest roentgenograms were performed until the pneumothoraces resolved. The majority of rabbits treated with oxygen had resolution of their pneumothoraces by 36 hours, whereas the majority of rabbits treated with room air did not show complete resolution before 48 hours. Biopsies showed no evidence of damage secondary to oxygen treatment. Oxygen treatment was found to be significantly better in the early resolution of pneumothoraces when compared with room air. This establishes an alternative treatment for some pneumothoraces that are small and asymptomatic.


Assuntos
Oxigênio/administração & dosagem , Pneumotórax/terapia , Animais , Causas de Morte , Coelhos , Indução de Remissão , Fatores de Tempo
15.
Res Dev Disabil ; 9(4): 377-91, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3205937

RESUMO

A critical component of supported competitive employment is the provision of long-term consumer assessment and systematic follow-along services. To date, there is a paucity of information that describes or validates the process of ongoing consumer assessment. In this article, written employer evaluations of workers with mental retardation were analyzed regarding their relationship to employment retention. Three factors were identified which related to employment retention: (a) workers' attendance, (b) punctuality patterns, and (c) consistency in task performance. These findings are discussed in light of their implications for curriculum design and habilitation efforts for persons with mental retardation.


Assuntos
Avaliação de Desempenho Profissional , Deficiência Intelectual/reabilitação , Gestão de Recursos Humanos , Reabilitação Vocacional/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Deficiência Intelectual/psicologia , Inteligência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Ajustamento Social
16.
Circ Res ; 60(4): 478-86, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2439227

RESUMO

The role of cytoskeletal damage in the disruption of the plasma membrane observed during myocardial ischemia has been studied using antibodies to vinculin to identify changes in the distribution of this membrane associated cytoskeletal protein. Vinculin is a component of the cytoskeletal attachment complex between the plasma membrane and the Z-line of the underlying myofibrils. The effects of varying periods of total ischemia on the localization of vinculin were assessed by immunofluorescence and evidence of membrane disruption was evaluated by electron microscopy. Thin tissue slices prepared from the ischemic tissue were incubated in oxygenated Krebs-Ringer phosphate buffer at 37 degrees C to assess inulin permeability, ultrastructure, and any changes in the distribution of vinculin associated with incubation. The previously reported costameric pattern of vinculin staining was observed in longitudinal sections of control myocardium, myocardium subjected to 60 minutes of total ischemia, and myocardium subjected to 60 minutes of ischemia followed by 60 minutes of incubation in oxygenated media. Electron microscopy and inulin permeability measurements confirmed that plasma membrane integrity was preserved under these conditions. However, when the duration of total ischemia was extended to 120 minutes or longer, there was a progressive loss of vinculin staining along the lateral margin of myocytes. This change correlates with the appearance of subsarcolemmal blebs and breaks in the plasma membranes observed by electron microscopy and confirmed by the increase in inulin permeability observed in tissue slices.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doença das Coronárias/patologia , Citoesqueleto/ultraestrutura , Proteínas Musculares/metabolismo , Animais , Membrana Celular/ultraestrutura , Doença das Coronárias/metabolismo , Citoesqueleto/metabolismo , Cães , Feminino , Imunofluorescência , Masculino , Microscopia Eletrônica , Coloração e Rotulagem , Fatores de Tempo , Vinculina
17.
Res Dev Disabil ; 8(1): 71-89, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3116610

RESUMO

A review of the literature on unemployment rates among adults with mental retardation is presented and the societal impact of the number of adults with mental retardation who remain unemployed is discussed. The supported competitive employment model is presented as illustrative of a habilitation program allowing greater monetary returns to society than traditional adult service programs. A benefit-cost analysis of our supported competitive employment program, occurring during the period from 1978 to 1986, is presented from two perspectives: that of the consumer (i.e., the adult with severe disabilities) and that of the taxpayer. Results of the benefit-cost analysis indicate that supported competitive employment is a financially prosperous venture from both perspectives. That is, from the consumers' perspective, for every $1.00 relinquished in taxes, supplemental security income (SSI), and forgone workshop earnings, $1.97 was received in increased income; the net benefit per year was $3,894 consumer. From the taxpayers' perspective, for every $1.00 expended for the funding of supported competitive employment programs and in lost tax revenues realized by the provision of targeted jobs tax credits, $1.87 was accumulated in benefits; the net yearly benefit to the taxpayer was $4,063 per consumer. The authors conclude that supported competitive employment is a financially profitable venture for both consumers and taxpayers.


Assuntos
Emprego , Deficiência Intelectual/reabilitação , Reabilitação Vocacional/economia , Adulto , Análise Custo-Benefício , Financiamento Governamental , Humanos
18.
Am J Physiol ; 251(6 Pt 2): H1306-15, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3789183

RESUMO

The effect of repetitive periods of coronary occlusion on myocardial adenine nucleotides, lactate, and infarct size was studied. In one series of dogs, the circumflex artery was occluded for one, two, or four 10-min episodes, each separated by 20 min of reperfusion. Hearts were excised and sampled for metabolic assays after one or more periods of ischemia before or after reperfusion. One 10-min period of ischemia caused a 61% loss of ATP and 41% loss of adenine nucleotides from the most severely ischemic subendocardial zone. Reperfusion resulted in rapid restoration of the adenylate charge but in only slight repletion of the adenine nucleotide pool. However, two or even four 10-min periods of ischemia caused no further adenine nucleotide loss. In contrast, 40 min of continuous coronary occlusion caused an 87% depletion of ATP and 67% of the adenine nucleotide pool from the same subendocardial region. Collateral blood flow was similar during all occlusions, but lactate accumulation was less during later occlusions. In a second series of experiments, myocardial necrosis was quantitated 4 days after four 10-min periods of ischemia. Necrosis was observed in only one of six dogs and, in this dog, was only 1.5% of the anatomic area at risk. Thus intermittent reperfusion prevents cumulative metabolic deficits and myocardial ischemic cell death, perhaps by restoring the capacity for high-energy phosphate (HEP) production and/or washing out deleterious catabolites. A first episode of ischemia also slows HEP utilization in subsequent episodes.


Assuntos
Trifosfato de Adenosina/metabolismo , Doença das Coronárias/fisiopatologia , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Animais , Pressão Sanguínea , Doença das Coronárias/patologia , Cães , Metabolismo Energético , Feminino , Cinética , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia , Necrose
19.
J Med Chem ; 29(5): 809-16, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3009815

RESUMO

The following 5-(2-substituted vinyl)-6-aza-2'-deoxyuridines were synthesized: (E)-5-(2-bromovinyl) (2) (6-aza-BVDU), 5-(2-bromo-2-fluorovinyl) (a mixture of E and Z isomers) (3), (E)-5-(2-chlorovinyl) (4), (E)-5-[2-(methylthio)vinyl] (5), 5-(2,2-dibromovinyl) (6), and 5-(3-furyl) (7). The synthesis of 2-6 utilized Wittig-type reactions on 5-formyl-1-(2'-deoxy-3', 5'-di-O-p-toluoyl-beta-D-erythro-pentofuranosyl)-6-azauracil (16). 6-Aza-BVDU (and its alpha-anomer) was also synthesized from (E)-5-(2-bromovinyl)-6-azauracil (12) by using standard deoxyribosidation methodology. Compound 7 was prepared from 5-(3-furyl)-6-azauracil (33) via a ribosidation/deoxygenation sequence. An attempt to prepare the corresponding 5-(2,2-difluorovinyl) analogue afforded instead a mixture of the 5-[(2,2-difluoro-2-methoxy)ethyl] and 5-(2,2,2-trifluoroethyl) derivatives 29 and 30. Compounds 2-7, 29, and 30 were tested for in vitro activity against herpes simplex virus types 1 and 2 (HSV-1, HSV-2). 6-Aza-BVDU (2) exhibited ID50s of 8 micrograms/mL vs. HSV-1 and 190 micrograms/mL vs. HSV-2. BVDU (1) had ID50s of 0.015 and 1.6 micrograms/mL against HSV-1 and HSV-2, respectively. Compound 4 showed a similar profile of activity, but the other analogues were either weakly active or inactive.


Assuntos
Antivirais/síntese química , Compostos Aza/síntese química , Desoxiuridina/análogos & derivados , Simplexvirus/efeitos dos fármacos , Compostos de Vinila/síntese química , Animais , Antivirais/farmacologia , Linhagem Celular , Haplorrinos , Relação Estrutura-Atividade
20.
Circ Res ; 57(6): 864-75, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4064260

RESUMO

The relationship between cell swelling and plasma membrane disruption has been evaluated in thin myocardial slices incubated in oxygenated or anoxic Krebs-Ringer phosphate media. Electron microscopy and measurements of inulin-diffusible space were used to monitor plasma membrane integrity. Inulin is excluded from the intracellular space of intact cells; therefore, an increase in tissue inulin content is an excellent marker of loss of plasma membrane integrity. Cell volume was increased during exposure of aerobic slices to hypotonic media, but the inulin-diffusible space was not increased and electron micrographs showed no detectable plasma membrane alterations. Likewise, during prolonged anoxic isotonic incubation, no evidence of plasma membrane damage was observed. Incubation in anoxic hypotonic media for 60 minutes resulted in a larger increase in cell volume than under aerobic conditions, but plasma membrane integrity was maintained. Extended anoxic hypotonic incubation (300 minutes) produced no further change in tissue water, but the inulin-diffusible space was increased and electron micrographs revealed breaks in the plasma membranes primarily in association with large subsarcolemmal blebs. Likewise, myocardial slices incubated in isotonic anoxic media for 240 minutes and hypotonic anoxic media for 60 minutes had an increased inulin-diffusible space and the ultrastructural appearance was similar. This ultrastructural appearance is indistinguishable from that observed in myocytes lethally injured by ischemia. Measurements of tissue osmolarity during total ischemia showed that osmotically induced cell swelling could occur in ischemic myocardium prior to the onset of plasma membrane disruption. Our results indicate that cell swelling per se is incapable of rupturing plasma membranes; however, after prolonged periods of energy deficiency, the plasma membrane or its cytoskeletal scaffold become injured, which allows the membrane to rupture if the cell is swollen, as might occur during ischemia or reperfusion.


Assuntos
Doença das Coronárias/fisiopatologia , Miocárdio/ultraestrutura , Sarcolema/fisiologia , Aerobiose , Anaerobiose , Animais , Permeabilidade da Membrana Celular , Cães , Feminino , Técnicas In Vitro , Masculino , Microscopia Eletrônica , Miocárdio/metabolismo , Equilíbrio Hidroeletrolítico
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