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1.
bioRxiv ; 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37398239

RESUMO

Mucosal barriers provide the first line of defense between internal body surfaces and microbial threats from the outside world. 1 In the colon, the barrier consists of two layers of mucus and a single layer of tightly interconnected epithelial cells supported by connective tissue and immune cells. 2 Microbes colonize the loose, outer layer of colonic mucus, but are essentially excluded from the tight, epithelial-associated layer by host defenses. 3 The amount and composition of the mucus is calibrated based on microbial signals and loss of even a single component of this mixture can destabilize microbial biogeography and increase the risk of disease. 4-7 However, the specific components of mucus, their molecular microbial targets, and how they work to contain the gut microbiota are still largely unknown. Here we show that high mobility group box 1 (HMGB1), the prototypical damage-associated molecular pattern molecule (DAMP), acts as an agent of host mucosal defense in the colon. HMGB1 in colonic mucus targets an evolutionarily conserved amino acid sequence found in bacterial adhesins, including the well-characterized Enterobacteriaceae adhesin FimH. HMGB1 aggregates bacteria and blocks adhesin-carbohydrate interactions, inhibiting invasion through colonic mucus and adhesion to host cells. Exposure to HMGB1 also suppresses bacterial expression of FimH. In ulcerative colitis, HMGB1 mucosal defense is compromised, leading to tissue-adherent bacteria expressing FimH. Our results demonstrate a new, physiologic role for extracellular HMGB1 that refines its functions as a DAMP to include direct, virulence limiting effects on bacteria. The amino acid sequence targeted by HMGB1 appears to be broadly utilized by bacterial adhesins, critical for virulence, and differentially expressed by bacteria in commensal versus pathogenic states. These characteristics suggest that this amino acid sequence is a novel microbial virulence determinant and could be used to develop new approaches to diagnosis and treatment of bacterial disease that precisely identify and target virulent microbes.

2.
Nonlinear Dynamics Psychol Life Sci ; 15(1): 11-28, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21176437

RESUMO

This article presents novel quantitative methods to study R to R interval (RRI) series that identify their characteristic pattern of organization, Bios, and their variation in psychiatric illness. In this study twenty-four hour series of RRI were extracted from Holter recordings of healthy subjects (N = 74) and small groups of patients with affective depression or psychosis. These data were analyzed with recurrence and statistical methods. In all subjects, RRI series showed complexes (clusters of recurrences), such as those observed with mathematically-generated biotic series but not in chaotic or random series. RRI series from healthy persons showed diversification (increase in variance with the duration of the series analyzed), novelty (less recurrence isometry than copies randomized by shuffling), causal order (more consecutive isometry than shuffled copies), and asymmetric statistical distribution. These imprints of creative processes are characteristic of mathematical Bios, and are absent in chaos. Bios can be distinguished from random walk series by the nonrandom pattern of the series of differences between heartbeats, as well as by measures of consecutive isometry and of partial autocorrelation. These defining characteristics of Bios are significant signs of health. In comparison with healthy controls, psychiatric patient groups showed more isometry and more consecutive isometry than healthy subjects. Psychiatric patients also showed no diversification. This study highlights the process that produces heart rate variation as being non-stationary and creative (bios, not equilibrium or chaos) and causal (not stochastically generated by the coexistence of multiple factors). These results thus are significant regarding psychiatric health.


Assuntos
Transtorno Bipolar/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Eletrocardiografia Ambulatorial/estatística & dados numéricos , Frequência Cardíaca/fisiologia , Modelos Teóricos , Esquizofrenia/fisiopatologia , Processamento de Sinais Assistido por Computador , Adulto , Idoso , Encéfalo/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Processos Estocásticos
3.
Artigo em Inglês | MEDLINE | ID: mdl-38274289

RESUMO

Objective: To assess early care and education professionals' breastfeeding knowledge and practices before and after an e-learning program. Participants: Early care and education professionals from New Hampshire (U.S.A.) licensed child care programs were invited to complete a pre-assessment followed by a 90-minute e-learning breastfeeding program. Three months post-training, participants were invited to complete the post-assessment. Analysis: McNemar tests were used to assess changes from pre-post-assessment for dichotomous variables. McNemar-Bowker tests were used to determine differences from pre-post for variables with more than two categories. When the McNemar-Bowker test was significant, a multiple comparison correction (Bonferroni) was used. Results: 114 participants completed the e-learning program and pre-post assessment. Results showed significant improvement from pre-post in 10 of 15 breastfeeding knowledge questions related to health of baby, mother and child care centers, economics, and environmental impact. There were significant changes from pre-post in 24 of 50 breastfeeding practice questions in handling breast milk, promoting breastfeeding, and supporting mothers. Conclusions and Implications: This study indicates improvement in early care and education professionals' breastfeeding knowledge and practices; however, opportunities exist to design targeted initiatives to further strengthen practices that support breastfeeding families in the child care environment.

4.
Bone ; 145: 115866, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33515777

RESUMO

INTRODUCTION: Osteonecrosis of the jaw (ONJ) is an adverse event that requires association of both systemic risk factors, such as powerful anti-resorptives (pARs; e.g. zoledronic acid [ZOL]), and local oral risk factors (e.g. tooth extraction, periodontitis). Whereas optimal oral health prior to initiate pARs is recognized as critically important for minimizing ONJ risk, the efficacy of preventive/maintenance measures in patients who are taking pARs is understudied. Rice rats fed a standard diet (STD), rich in insoluble fiber, develop localized periodontitis. STD-rats with localized periodontitis treated with ZOL for 18-24 wk develop ONJ. Hence, we hypothesized that controlling/preventing localized periodontitis in the ZOL-treated rats, reduces ONJ occurrence. METHODS: We used two approaches to attempt reducing periodontitis prevalence: 1) periodontal cleaning (PC); and 2) replacing the STD-diet with a nutritionally-equivalent diet high in soluble fiber (SF). 75 four-week-old male rats were weight-randomized into five groups (n = 15) in a 24-week experiment. Three groups ate the STD-diet and two the high SF-diet. STD-diet groups received intravenous (IV) vehicle (VEH) q4wks (STD + VEH), 80 µg/kg ZOL q4wks IV (STD + ZOL), or ZOL plus PC q2wks (STD + ZOL + PC). The SF-diet groups received VEH (SF + VEH) or ZOL (SF + ZOL). Jaws were processed for histopathology and evaluated for ONJ prevalence and tissue-level periodontitis. RESULTS: 1) 40% of STD + VEH rats developed maxillary localized periodontitis with no ONJ; 2) 50% of STD + ZOL rats developed ONJ; 3) 7% of STD + ZOL + PC rats developed ONJ (p < 0.01 vs. STD + ZOL); and 4) one SF + ZOL rat developed localized periodontitis, and no SF + VEH or SF + ZOL rats developed ONJ (p < 0.001 vs. STD + ZOL). CONCLUSIONS: 1) Periodontal cleaning in ZOL-treated rats decreases localized periodontitis severity and reduces ONJ prevalence; and 2) feeding a SF-diet to ZOL-treated rats reduces both incidence of localized periodontitis and ONJ. Our data indicates strong oral microbial community shifts according to oral health condition and trends in the shifts associated with diet.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Osteonecrose , Periodontite , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Difosfonatos/uso terapêutico , Humanos , Arcada Osseodentária , Masculino , Periodontite/prevenção & controle , Ratos , Sigmodontinae , Ácido Zoledrônico
5.
Psychol Med ; 40(9): 1453-66, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19939326

RESUMO

BACKGROUND: Data from a representative community sample were used to explore predictors of lifetime suicidality and to examine associations between distal adolescent and more proximal adult risks. METHOD: Data are from a midlife follow-up of the Isle of Wight study, an epidemiological sample of adolescents assessed in 1968. Ratings of psychiatric symptoms and disorder, relationships and family functioning and adversity were made in adolescence; adult assessments included lifetime psychiatric history and suicidality, neuroticism and retrospective reports of childhood sexual abuse and harsh parenting. RESULTS: A wide range of measures of childhood psychopathology, adverse experiences and interpersonal difficulties were associated with adult suicidality; associations were particularly strong for adolescent irritability, worry and depression. In multivariate analyses, substantial proportions of these effects could be explained by their association with adult psychopathology and neuroticism, but additional effects remained for adolescent irritability and worry. CONCLUSIONS: Factors of importance for long-term suicidality risk are evident in adolescence. These include family and experiential adversities as well as psychopathology. In particular, markers of adolescent worry and irritability appeared both potent risks and ones with additional effects beyond associations with adult disorder and adult neuroticism.


Assuntos
Acontecimentos que Mudam a Vida , Suicídio/psicologia , Adolescente , Adulto , Abuso Sexual na Infância/psicologia , Transtorno Depressivo/epidemiologia , Inglaterra/epidemiologia , Feminino , Humanos , Funções Verossimilhança , Masculino , Poder Familiar , Personalidade , Estudos Prospectivos , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Suicídio/estatística & dados numéricos , Temperamento , Prevenção do Suicídio
6.
Bone ; 130: 115141, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31707108

RESUMO

OBJECTIVE: Angiogenesis inhibitors (AgI) are commonly used in combination chemotherapy protocols to treat cancer, and have been linked to osteonecrosis of the jaw (ONJ). However, it is unknown if AgI therapy alone is sufficient to induce ONJ. We have previously established an ONJ model in rice rats with localized periodontitis that receive zoledronic acid (ZOL). The purpose of this study was to use this model to determine the role of anti-vascular endothelial growth factor A (anti-VEGF) antibody treatment of rice rats with localized maxillary periodontitis. We hypothesized that rice rats with localized maxillary periodontitis given anti-VEGF monotherapy will develop oral lesions that resemble ONJ, defined by exposed, necrotic alveolar bone. METHODS: At age 4 weeks, 45 male rice rats were randomized into three groups (n = 15): 1) VEH (saline), 2) ZOL (80 µg/kg body weight, intravenously once monthly), and 3) anti-VEGF (5 mg B20-4.1.1/kg body weight, subcutaneously twice weekly). After 24 weeks, rats were euthanized, jaws were excised and a high-resolution photograph of each quadrant was taken to assign a severity grade based on gross appearance. Jaws were then fixed, scanned by MicroCT, decalcified and sectioned for histopathologic and immunohistochemical analyses. RESULTS: 40-80% of the rats in the three groups developed gross oral lesions. 50% of ZOL rats developed ONJ. In contrast, 80% of the anti-VEGF rats developed destructive advanced periodontitis that was characterized by extreme alveolar bone loss and fibrosis. Anti-VEGF rats never developed exposed, necrotic bone. Furthermore, only anti-VEGF rats developed mild to severe mandibular periodontitis. Compared to VEH rats, more T-cells were found in periodontal lesions of anti-VEGF rats and more cells of the monocyte lineage were found in ONJ lesions of ZOL rats. CONCLUSIONS: Anti-VEGF monotherapy administered to a validated rodent model of ONJ caused a destructive advanced form of periodontitis that differed significantly from ONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Osteonecrose , Periodontite , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Difosfonatos/efeitos adversos , Masculino , Periodontite/tratamento farmacológico , Ratos , Sigmodontinae , Microtomografia por Raio-X , Ácido Zoledrônico/efeitos adversos
7.
Am J Med Genet A ; 149A(10): 2173-80, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19764032

RESUMO

Ciliopathies are an expanding group of rare conditions characterized by multiorgan involvement, that are caused by mutations in genes encoding for proteins of the primary cilium or its apparatus. Among these genes, CEP290 bears an intriguing allelic spectrum, being commonly mutated in Joubert syndrome and related disorders (JSRD), Meckel syndrome (MKS), Senior-Loken syndrome and isolated Leber congenital amaurosis (LCA). Although these conditions are recessively inherited, in a subset of patients only one CEP290 mutation could be detected. To assess whether genomic rearrangements involving the CEP290 gene could represent a possible mutational mechanism in these cases, exon dosage analysis on genomic DNA was performed in two groups of CEP290 heterozygous patients, including five JSRD/MKS cases and four LCA, respectively. In one JSRD patient, we identified a large heterozygous deletion encompassing CEP290 C-terminus that resulted in marked reduction of mRNA expression. No copy number alterations were identified in the remaining probands. The present work expands the CEP290 genotypic spectrum to include multiexon deletions. Although this mechanism does not appear to be frequent, screening for genomic rearrangements should be considered in patients in whom a single CEP290 mutated allele was identified.


Assuntos
Anormalidades Múltiplas/genética , Antígenos de Neoplasias/genética , Cílios , Proteínas de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Sequência de Bases , Proteínas de Ciclo Celular , Cílios/genética , Cílios/patologia , Proteínas do Citoesqueleto , Análise Mutacional de DNA , Feminino , Feto/metabolismo , Feto/patologia , Deleção de Genes , Testes Genéticos , Humanos , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/análise , Síndrome
8.
Science ; 180(4092): 1297-8, 1973 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-4707917

RESUMO

The mechanical performance of hypoxic heart muscle is further depressed by an acid pH. In contrast to preparations at normal or alkaline pH. however, hypoxic preparations at acid pH do not develop contracture and exhibit full recovery of mechanical activity upon reoxygenation.


Assuntos
Acidose/fisiopatologia , Coração/fisiopatologia , Hipóxia/fisiopatologia , Equilíbrio Ácido-Base , Acidose/etiologia , Alcalose/fisiopatologia , Animais , Dióxido de Carbono/farmacologia , Doença das Coronárias/metabolismo , Doença das Coronárias/fisiopatologia , Estimulação Elétrica , Coração/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hipóxia/complicações , Isquemia/complicações , Contração Muscular , Nitrogênio/farmacologia , Oxigênio/farmacologia , Ratos
9.
J Child Psychol Psychiatry ; 50(8): 893-901, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19490310

RESUMO

BACKGROUND: Developmental reading problems show strong persistence across the school years; less is known about poor readers' later progress in literacy skills. METHOD: Poor (n = 42) and normally developing readers (n = 86) tested in adolescence (ages 14/15 years) in the Isle of Wight epidemiological studies were re-contacted at mid-life (ages 44/45 years). Participants completed a spelling test, and reported on educational qualifications, perceived adult spelling competence, and problems in day-to-day literacy tasks. RESULTS: Individual differences in spelling were highly persistent across this 30-year follow-up, with correlations between spelling at ages 14 and 44 years of r = .91 (p < .001) for poor readers and r = .89 (p < .001) for normally developing readers. Poor readers' spelling remained markedly impaired at mid-life, with some evidence that they had fallen further behind over the follow-up period. Taking account of adolescent spelling levels, continued exposure to reading and literacy demands in adolescence and early adulthood was independently predictive of adult spelling in both samples; family social background added further to prediction among normally developing readers only. CONCLUSIONS: By adolescence, individual differences in spelling and its related sub-skills are highly stable. Encouraging young people with reading disabilities to maintain their exposure to reading and writing may be advantageous in the longer term.


Assuntos
Dislexia/diagnóstico , Escolaridade , Aprendizagem Verbal , Redação , Adolescente , Adulto , Escolha da Profissão , Criança , Dislexia/epidemiologia , Feminino , Humanos , Individualidade , Atividades de Lazer , Estudos Longitudinais , Masculino , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Leitura , Reino Unido , Adulto Jovem
10.
Bone ; 108: 79-88, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29289789

RESUMO

OBJECTIVE: Investigate role of dose/duration of zoledronic acid (ZOL), a powerful anti-resorptive (pAR), on prevalence of medication-related osteonecrosis of the jaw (MRONJ) in rice rats (Oryzomys palustris), a species with natural susceptibility to food impaction-induced localized periodontitis (FILP). We hypothesize that ZOL induces MRONJ lesions in rice rats with FILP, and that the prevalence of MRONJ rises with increasing dose and duration of ZOL treatment. METHODS: We performed a toxicology experiment with clinically-relevant doses of ZOL in female rats (N=230) fed standard (STD) rodent chow. At age 4weeks (baseline), 12 rats were necropsied. The rest were randomized into five groups that began to receive 0, 8, 20, 50 or 125µg/kg ZOL IV/q 4weeks. After 12, 18, 24 and 30weeks, subgroups (N=9-16) from each of the dose groups were necropsied. High-resolution macroscopic photos of all jaw quadrants were given a gross quadrant grade (GQG) (0-4 or MRONJ) that classified FILP lesion severity and determined presence of gross MRONJ. Quadrants with GQG≥1 were examined histopathologically. Logistic regression analysis (ZOL dose/duration) of MRONJ prevalence was completed. RESULTS: We found: 1) 75% of 0µg/kg ZOL rats developed FILP lesions; 2) baseline rats and rats treated with 0µg/kg ZOL had no MRONJ; 3) 29 gross MRONJ cases were identified; 4) all gross MRONJ cases were confirmed histopathologically by the observation of exposed necrotic bone, and 53 new cases were discovered (total=82); 5) ZOL dose (P<0.001), but not duration (P=0.326), was a significant predictor of MRONJ prevalence; 6) 13% prevalence of gross MRONJ among all rats, with 22% prevalence among rats exposed to ZOL oncologic doses (20-125µg/kg); 7) 38% prevalence of histopathologic MRONJ among all rats, with 73% prevalence among rats exposed to ZOL oncologic doses. CONCLUSIONS: This is the first experiment to show a dose response relationship between clinically relevant doses of ZOL and MRONJ prevalence.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/epidemiologia , Periodontite/complicações , Ácido Zoledrônico/efeitos adversos , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , Peso Corporal , Reabsorção Óssea/patologia , Relação Dose-Resposta a Droga , Feminino , Fêmur/patologia , Osteócitos/patologia , Periodontite/patologia , Prevalência , Sigmodontinae , Resultado do Tratamento
11.
J Clin Invest ; 77(5): 1482-6, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3700650

RESUMO

The development of atherosclerotic changes and thromboembolism are common features in homocystinurics. Hence, we postulate a positive correlation between the level of homocyst(e)ine in the blood and the occurrence of coronary artery disease. Homocysteine is found either as free homocystine, cysteine-homocysteine mixed disulfide, or protein-bound homocyst(e)ine. In nonhomocystinuric subjects, most homocysteine molecules are detectable in the protein-bound form. Thus, protein-bound homocyst(e)ine in stored plasma which reflected total plasma homocyst(e)ine was determined in 241 patients with coronary artery disease (173 males and 68 females). The mean +/- SD total plasma homocyst(e)ine was 5.41 +/- 1.62 nmol/ml in male patients, 4.37 +/- 1.09 nmol/ml in male controls, 5.66 +/- 1.93 nmol/ml in female patients, and 4.16 +/- 1.62 nmol/ml in female controls. The differences between the patients with coronary artery disease and the controls were statistically significant (P less than 0.0005).


Assuntos
Proteínas Sanguíneas/metabolismo , Doença das Coronárias/etiologia , Homocisteína/sangue , Homocistina/sangue , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Menopausa , Pessoa de Meia-Idade , Ligação Proteica , Risco , Fatores Sexuais
12.
Arch Pediatr ; 14(5): 485-9, 2007 May.
Artigo em Francês | MEDLINE | ID: mdl-17320360

RESUMO

Idiopathic apneas of prematurity remain an alarming problem in neonatology. Long-term effects on neurological development cannot be excluded. Two principal treatments are currently applied to prevent apneic attacks: analeptics (methylxanthines and doxapram) and continuous positive airway pressure. Several studies suggest the use of sensory stimulations for curative or preventive treatments. Protocols of tactile, kinesthetic and auditory stimulations are described and their respective efficacy is discussed. We also resume a recent preliminary study which suggested the use of an olfactory stimulation as preventive treatment. A beneficial effect, specifically on apnea associated with severe bradycardia, was observed. Complementary studies are necessary to confirm the benefit of such sensory stimulations for apneas of prematurity, and, if so, to allow clinical applications.


Assuntos
Estimulação Acústica , Apneia/terapia , Doenças do Prematuro/terapia , Odorantes , Tato , Bradicardia/prevenção & controle , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro
13.
Arch Pediatr ; 14(1): 45-53, 2007 Jan.
Artigo em Francês | MEDLINE | ID: mdl-17046221

RESUMO

This document reviews the main data relating to the structural and functional organisation of olfactory perception in the premature newborn. The chemoreceptive systems (main olfactory, trigeminal, vomeronasal and terminal systems) develop in different chronological orders but quite at very early stage during ontogeny. The premature newborn, despite being immature, has been shown to react to a wide variety of olfactory stimuli. Moreover, the infant seems capable of distinguishing odours of different qualities and intensities, memorising stimuli to which he is regularly exposed to, and categorising different odours based on their hedonic valence. An inventory of the olfactory stimuli to which the infant is regularly exposed to in the incubator is carried out. Several attempts to use pleasant and familiar odours to reduce stress due to separation of the infant from its mother, to promote oral feeding, to make medical procedures more acceptable, and more so, to reduce the respiratory instability of the premature infant, are described. If sustained attention is directed to the olfactory characteristics dwelling inside the incubator, the well-being, health and development of the premature newborn could be improved.


Assuntos
Recém-Nascido Prematuro/fisiologia , Olfato/fisiologia , Adaptação Fisiológica , Células Quimiorreceptoras/fisiologia , Humanos , Recém-Nascido
14.
Mucosal Immunol ; 10(3): 567-579, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28145439

RESUMO

Since microbes were first described in the mid-1600s, we have come to appreciate that they live all around and within us with both beneficial and detrimental effects on nearly every aspect of our lives. The human gastrointestinal tract is inhabited by a dynamic community of trillions of bacteria that constantly interact with each other and their human host. The acquisition of these bacteria is not stochastic but determined by circumstance (environment), host rules (genetics, immune state, mucus, etc), and dynamic self-selection among microbes to form stable, resilient communities that are in balance with the host. In this review, we will discuss how these factors lead to formation of the gut bacterial community and influence its interactions with the host. We will also address how gut bacteria contribute to disease and how they could potentially be targeted to prevent and treat a variety of human ailments.


Assuntos
Bactérias , Evolução Biológica , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Enteropatias/microbiologia , Exposição Ambiental , Trato Gastrointestinal/imunologia , Homeostase , Interações Hospedeiro-Patógeno , Humanos , Imunidade nas Mucosas , Enteropatias/imunologia
15.
Biochim Biophys Acta ; 976(1): 42-52, 1989 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-2765537

RESUMO

Substrate-dependent changes in vascular smooth muscle energy metabolism and contractile function were investigated in isolated porcine carotid arteries. In media containing glucose glycogen catabolism accounted for all the estimated high-energy phosphate turnover that occurred in conjunction with contraction induced by 80 mM KCl. However, in glucose-free media glycogen catabolism accounted for only a portion of the estimated ATP utilization in resting and contracting arteries, even though glycogen stores were not depleted. The glycogenolysis and lactate production that ordinarily accompanies contraction was completely inhibited by 5 mM 2-deoxyglucose (2-DG). However, there was no decrease in the high-energy phosphate levels when compared to control resting arteries similarly treated with 2-DG. The results suggest that an endogenous non-carbohydrate source may be an important substrate for energy metabolism. Treatment of arteries with 50 microM iodoacetate (IA) in media containing glucose resulted in a marked reduction of high energy phosphate levels and an accumulation of phosphorylated glycolytic intermediates, as demonstrated by 31P-NMR spectroscopy. In glucose-free media, 50 microM IA had only a slight effect on high-energy phosphate levels, while glycogenolysis proceeded unhindered. With 1 mM IA in glucose-free media, the oxidative metabolism of glycogen was inhibited as evidenced by the depletion of high-energy phosphates and the appearance of sugar phosphates in the 31P-NMR spectra. Thus, the titration of enzyme systems with IA reveals a structural partitioning of carbohydrate metabolism, as suggested by previous studies.


Assuntos
Metabolismo dos Carboidratos , Contração Muscular , Músculo Liso Vascular/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Artérias Carótidas , Fenômenos Químicos , Físico-Química , Desoxiglucose/farmacologia , Metabolismo Energético , Glucose/metabolismo , Glicogênio/metabolismo , Concentração de Íons de Hidrogênio , Iodoacetatos/farmacologia , Ácido Iodoacético , Lactatos/metabolismo , Ácido Láctico , Espectroscopia de Ressonância Magnética , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Fosfatos/metabolismo , Fosfocreatina/metabolismo , Cloreto de Potássio/farmacologia , Suínos
16.
J Am Coll Cardiol ; 13(2): 340-7, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2913112

RESUMO

Recent technology in Doppler echocardiography has produced a dual beam Doppler instrument that is capable of insonating the total cross-sectional area of the ascending aorta. The purpose of this study was to evaluate the accuracy of this instrument in measuring cardiac output in critically ill patients by comparing results with those of the thermodilution-derived cardiac output. A technically adequate Doppler cardiac output measurement was attained in 71 (91%) of 78 patients. The range of thermodilution-derived cardiac output measurements was from 1.58 to 11.70 liters/min. To maximize thermodilution cardiac output reliability, several measurements were made for each patient. Those patients in whom the difference between the highest and lowest measurement varied by less than 10% from the averaged results were accepted into the 50 patient study. There was significant correlation between dual beam Doppler- and thermodilution-derived cardiac output (r = 0.96, SEE = 0.55 liters/min, p less than 0.0001). This study demonstrates that dual beam Doppler ultrasound is a promising noninvasive method of measuring cardiac output in the critically ill patient.


Assuntos
Débito Cardíaco , Ecocardiografia Doppler , Injúria Renal Aguda/fisiopatologia , Velocidade do Fluxo Sanguíneo , Cuidados Críticos , Cardiopatias/fisiopatologia , Humanos , Infecções/fisiopatologia , Insuficiência Respiratória/fisiopatologia , Termodiluição
17.
J Am Coll Cardiol ; 12(3): 858-62, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3403853

RESUMO

The number of cardiologists can be projected with considerable accuracy into the next century. The total cardiology pool of physicians will increase until the year 2015 at which time those entering and leaving the pool will come into equilibrium. At that time the ratio of active cardiologists to the population will have greatly increased. This nation's future need for cardiologists is difficult to assess with any degree of precision. Therefore, this is the time for updating practice profile studies. Such studies today could be formulated in a manner to provide more detailed information on the cardiologist's daily activities. In addition, a data base developed through methodology such as the consensus formation approach must be developed and updated on a periodic basis. Through such analyses it will be possible to quantitate the future needs of cardiovascular manpower.


Assuntos
Cardiologia , Mão de Obra em Saúde , Especialização , Adulto , Médicos Graduados Estrangeiros , Humanos , Medicina Interna , Estados Unidos
18.
Arch Intern Med ; 142(4): 711-4, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7073414

RESUMO

Although the formation of a left ventricular aneurysm (LVA) is a common and well-recognized complication of myocardial infarction (MI), diaphragmatic LVA is a rare clinical entity. Of 354 consecutive patients who underwent LVA resection, we describe the clinical features and surgical results of 22 patients (6%) with diaphragmatic LVA. All patients had a history of MI. The principal clinical indication for surgery was heart failure in nine patients, angina pectoris in ten patients, and recurrent ventricular tachycardia unresponsive to medical therapy in three patients. A ventricular septal defect was present in two patients, and moderate to severe mitral regurgitation was present in four patients. Three of the four surgical deaths (operative mortality, 18%) occurred in patients with mitral regurgitation or with ventricular septal defect. Eleven patients are alive at a mean follow-up of 40 months. Six of them are asymptomatic and two have angina at a higher level of physical activity than before surgery. Notable differences exist in the clinical presentation and surgical findings between patients with diaphragmatic and anterior LVA.


Assuntos
Aneurisma Cardíaco/cirurgia , Adulto , Idoso , Angiografia Coronária , Diafragma , Emergências , Feminino , Seguimentos , Aneurisma Cardíaco/diagnóstico por imagem , Aneurisma Cardíaco/fisiopatologia , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
19.
Cardiovasc Res ; 9(1): 38-46, 1975 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1122509

RESUMO

Using potassium cyanide (KCN) to stimulate hypoxia, the effects of intracoronary injections of KCN were compared with total occlusions of the same vessel. Imparied contraction as measured by segment length gauges was of equally abrupt onset following both interventions. The magnitude of systolic expansion at one minute was more marked following total occlusion than after KCN administration.


Assuntos
Doença das Coronárias/fisiopatologia , Cianetos/farmacologia , Hipóxia/fisiopatologia , Contração Miocárdica , Animais , Dióxido de Carbono/farmacologia , Cateterismo Cardíaco , Vasos Coronários/efeitos dos fármacos , Estimulação Elétrica , Técnicas In Vitro , Iodoacetatos/farmacologia , Ligadura , Masculino , Contração Miocárdica/efeitos dos fármacos , Músculos Papilares/efeitos dos fármacos , Potássio , Ratos
20.
Atherosclerosis ; 59(1): 57-62, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3947423

RESUMO

31P-nuclear magnetic resonance spectroscopy was used to assess phosphate metabolites in perchloric acid extracts of rabbit aorta. In addition to the high energy phosphates, several other phosphorus compounds were detected and quantified. Most notable was the presence of a prominent phosphomonoester compound appearing at a chemical shift of 3.86 delta. This compound constituted 26% of the total extractable tissue phosphorus and is tentatively identified as ribose-5-phosphate, a pentose phosphate pathway intermediate. While ATP and phosphocreatine did not change during glucose and oxygen deprivation or during prolonged muscle contraction, the 3.86 delta phosphate decreased significantly. Furthermore, theophylline, an agent that increases intracellular cAMP, also decreased the level of the 3.86 delta phosphate. These results are consistent with the concept that intermediate metabolism sustains high energy phosphate pools in vascular smooth muscle in the steady state under various conditions. The pentose phosphate pathway may play an important role in vascular smooth muscle metabolism.


Assuntos
Espectroscopia de Ressonância Magnética , Músculo Liso Vascular/anatomia & histologia , Animais , Aorta Torácica , Glucose/farmacologia , Masculino , Oxigênio/farmacologia , Via de Pentose Fosfato/efeitos dos fármacos , Isótopos de Fósforo , Coelhos , Ribosemonofosfatos/análise , Teofilina/farmacologia
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