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1.
HIV Med ; 21(4): 217-227, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31729142

RESUMO

OBJECTIVES: Elite controllers (ECs), viraemic controllers (VCs), and long-term nonprogressors (LTNPs) control HIV viral replication or maintain CD4 T-cell counts without antiretroviral therapy, but may have increased cardiovascular disease (CVD) risk compared to HIV-uninfected persons. We evaluated subclinical carotid and coronary atherosclerosis and inflammatory biomarker levels among HIV controllers, LTNPs and noncontrollers and HIV-uninfected individuals in the Multicenter AIDS Cohort Study (MACS) and the Women's Interagency HIV Study (WIHS). METHODS: We measured carotid plaque presence and common carotid artery intima-media thickness (IMT) in 1729 women and 1308 men, and the presence of coronary artery calcium and plaque in a subgroup of men. Associations between HIV control category and carotid and coronary plaque prevalences were assessed by multivariable regression analyses adjusting for demographics and CVD risk factors. Serum inflammatory biomarker concentrations [soluble CD163 (sCD163), soluble CD14 (sCD14), galectin-3 (Gal-3), galectin-3 binding protein (Gal-3BP) and interleukin (IL)-6] were measured and associations with HIV control category assessed. RESULTS: We included 135 HIV controllers (30 ECs) and 135 LTNPs in the study. Carotid plaque prevalence and carotid IMT were similar in HIV controllers, LTNPs and HIV-uninfected individuals. HIV controllers and LTNPs had lower prevalences of carotid plaque compared to viraemic HIV-infected individuals. The prevalence of coronary atherosclerosis was similar in HIV controllers/LTNPs compared to HIV-uninfected and viraemic HIV-infected men. Controllers and LTNPs had higher concentrations of sCD163 and sCD14 compared to HIV-uninfected persons. CONCLUSIONS: Subclinical CVD was similar in HIV controllers, LTNPs and HIV-uninfected individuals despite elevated levels of some inflammatory biomarkers. Future studies of HIV controllers and LTNPs are needed to characterize the risk of CVD among HIV-infected persons.


Assuntos
Biomarcadores/sangue , Doenças das Artérias Carótidas/diagnóstico por imagem , Infecções por HIV/complicações , Sobreviventes de Longo Prazo ao HIV/estatística & dados numéricos , Adulto , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Contagem de Linfócito CD4 , Cálcio/metabolismo , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/imunologia , Espessura Intima-Media Carotídea , Estudos de Coortes , Feminino , Infecções por HIV/sangue , Infecções por HIV/imunologia , Humanos , Receptores de Lipopolissacarídeos/sangue , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Receptores de Superfície Celular/sangue , Tomografia Computadorizada por Raios X , Adulto Jovem
2.
Neurobiol Dis ; 124: 408-415, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30592975

RESUMO

The spread of epileptic seizure activity to brainstem respiratory and autonomic regions can elicit episodes of obstructive apnea and of central apnea with significant oxygen desaturation and bradycardia. Previously, we argued that central apneic events were not consequences of respiratory or autonomic activity failure, but rather an active brainstem behavior equivalent to the diving response resulting from seizure spread. To test the similarities of spontaneous seizure-associated central apneic episodes to evoked diving responses, we used nasopharyngeal irrigation with either cold water or mist for 10 or 60 s to elicit the diving response in urethane-anesthetized animals with or without kainic acid-induced seizure activity. Diving responses included larger cardiovascular changes during mist stimuli than during water stimuli. Apneic responses lasted longer than 10 s in response to 10 s stimuli or about 40 s in response to 60 s stimuli, and outlasted bradycardia. Repeated 10 s mist applications led to an uncoupling of the apneic episodes (which always occurred) from the bradycardia (which became less pronounced with repetition). These uncoupled events matched the features of observed spontaneous seizure-associated central apneic episodes. The duration of spontaneous central apneic episodes correlated with their frequency, i.e. longer events occurred when there were more events. Based on our ability to replicate the properties of seizure-associated central apneic events with evoked diving responses during seizure activity, we conclude that seizure-associated central apnea and the diving response share a common neural basis and may reflect an attempt by brainstem networks to protect core physiology during seizure activity.


Assuntos
Reflexo de Mergulho/fisiologia , Convulsões/complicações , Apneia do Sono Tipo Central/etiologia , Apneia do Sono Tipo Central/fisiopatologia , Animais , Fenômenos Fisiológicos Cardiovasculares , Masculino , Ratos , Ratos Sprague-Dawley
3.
HIV Med ; 14(9): 549-55, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23738819

RESUMO

OBJECTIVES: HIV infection is associated with higher than expected cardiovascular event rates and lowered platelet counts. These conditions are associated with an elevation of mean platelet volume (MPV). The present study compared MPV in HIV-infected and uninfected women and identified factors influencing MPV values in HIV-infected women. METHODS: A total of 234 HIV-infected and 134 HIV-uninfected participants from the Women's Interagency HIV Study (WIHS) had MPV values obtained. HIV-infected women were older, were more likely to have diabetes and had higher triglyceride levels than HIV-uninfected women. RESULTS: The mean platelet count was lower in HIV-infected vs. uninfected women [249 cells/µL (95% confidence interval (CI) 238, 259 cells/µL) vs. 276 cells/µL (95% CI 265, 287 cells/µL), respectively; P < 0.01]. Adjusted mean MPV values were lower in the HIV-infected than in the uninfected group [8.66 fL (95% CI 8.52, 8.79 fL) vs. 9.05 fL (95% CI 8.87, 9.24 fL), respectively]. In multiple regression analysis, after adjusting for other covariates, MPV was positively associated with platelet count, and negatively with HIV infection (model R² = 0.20; P < 0.01). In multiple regression analysis confined to HIV-infected women, a lower MPV was independently associated with a history of AIDS-defining illness (R² = 0.28; P = 0.03), but not with nadir CD4 count or highly active antiretroviral therapy (HAART) use. CONCLUSIONS: HIV-infected women had lower MPV values than uninfected women, suggesting impaired production rather than increased destruction. Higher than expected cardiovascular event rates cannot be attributed to greater platelet reactivity as measured by MPV.


Assuntos
Infecções por HIV/sangue , Volume Plaquetário Médio , Adulto , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Estudos de Casos e Controles , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/epidemiologia
4.
Plant Dis ; 96(10): 1582, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30727331

RESUMO

Raspberry bushy dwarf virus (RBDV) is the sole member of genus Idaeovirus and naturally infects Rubus species worldwide. It can be experimentally transmitted to many dicotyledonous plant species from different families. In Slovenia it has been reported to naturally infect grapevine, the first known non-Rubus natural host (3). However, RBDV from red raspberry and grapevine were found to be different in biological, serological, and molecular characteristics (4). From 2007 to 2010, grapevine (Vitis vinifera L.) vineyards were sampled in different parts of Hungary and tested for RBDV infection by double antibody sandwich (DAS)-ELISA using commercial reagents (Bioreba, Reinach, Switzerland). Overall, 181 samples were collected from 10 vineyards around Csörnyeföld, Badacsony, Eger, Tolcsva (Orémus), and Nagyréde. Samples were taken randomly unless plants showing virus-like symptoms were present, which were preferentially included in the survey. Two samples collected in 2010, each consisting of five leaves from five individual plants, tested positive by DAS-ELISA. They originated from a small private vineyard of Italian Riesling, Pinot Gris, and Rhein Riesling in the southwestern part of Hungary near Csörnyeföld where 29 samples were collected. All leaves were asymptomatic. Total RNA was extracted from positive samples using a RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). cDNA was synthesized using primer RNA12 as described (4) and further amplified by PCR using primers RBDVUP1/RBDVLO4 that amplified an 872-bp fragment of RBDV coat protein and 3' non-translated region (2). Amplification products from both samples were directly sequenced (Macrogen, Seoul, Korea). The sequences showed 98.6% identity between each other and were deposited in GenBank (Accession Nos. JQ928628 and JQ928629). Sequences were also compared with RBDV sequences deposited in GenBank. They showed 97.7 to 99.3% identity with RBDV sequences from grapevine from Slovenia and 94.2 to 96.1% with RBDV sequences from Rubus sp. Natural infection of grapevine with RBDV was first reported from Slovenia in 2003 (3) and was recently reported also from Serbia (1). To our knowledge, this is the first report of RBDV infection of grapevine in Hungary and suggests a wider presence of the virus in the region. References: (1) D. Jevremovic and S. Paunovic. Pestic. Phytomed. (Belgrade) 26:55, 2011. (2) H. I. Kokko et al. BioTechniques 20:842, 1996. (3) I. Mavric Plesko et al. Plant Dis. 87:1148, 2003. (4) I. Mavric Plesko et al. Eur. J. Plant Pathol. 123:261, 2009.

5.
J Hist Neurosci ; 31(2-3): 368-393, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35584551

RESUMO

This article is an outline of the transition in "brain maps" used to illustrate locations of cortical "centers" associated with movements, sensations, and language beginning with images from Gall and Spurzheim in the nineteenth century through those of functional magnetic resonance imaging in the twenty-first century. During the intervening years, new approaches required new brain maps to illustrate them, and brain maps helped to objectify and naturalize mental processes. One approach, electrical stimulation of the cerebral cortex-exemplified by Fritsch and Hitzig in 1870, Ferrier in 1873, and Penfield by 1937-required brain maps showing functional centers with expanded and overlapping boundaries. In another approach, brain maps that linked cortical centers to account for the complex syndromes of aphasia, apraxia, alexia, and agraphia were initially constructed by Baginsky in 1871, Wernicke in 1874, and Lichtheim in 1885, then later by Lissauer in 1890, Dejerine in 1892, and Liepmann in 1920, and eventually by Geschwind in 1965 and others through the late twentieth century. Over that intervening time, brain maps changed from illustrations of points on the cerebral cortex where movements and sensations were elicited to illustrations of areas (centers) associated with recognizable functions to illustrations of connections between those areas that account for complex symptoms occurring in clinical patients. By the end of this period, advancements in physics, mathematics, and cognitive science resulted in inventions that allowed brain maps of cortical locations derived from cognitive manipulations rather than from the usual electrical or ablative manipulations. "Mental" dependent variables became "cognitive" independent variables.


Assuntos
Mapeamento Encefálico , Encéfalo , Mapeamento Encefálico/história , Córtex Cerebral , História do Século XIX , Humanos , Idioma , Sensação
6.
J Hist Neurosci ; 31(4): 409-424, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995173

RESUMO

Medical interest in the knee-jerk reflex began in about 1875 with simultaneous and independent publications by Wilhelm Heinrich Erb (1840-1921) and Carl Friedrich Otto Westphal (1833-1890) contending that the knee jerk was absent (and the ankle clonus was present) in all clear cases of locomotor ataxia (tabes dorsalis). Physicians in the medical communities of Europe, Great Britain, and North America responded with case and large group studies that tested this contention. These studies revealed the usefulness of the knee jerk and other myotatic reflexes, but also unexpected characteristics. The knee jerk, apparently so simple, proved to be a complex phenomenon depending the strength of the strike on the patella, induced muscle tension, and inhibition from the brain. Was it a reflex with afferent and efferent nerves and an intervening process in the spinal cord, or was it a local phenomenon confined to the muscle itself? Experimental studies directed at the reflex issue investigated latencies from patella strike to leg extension or muscle contraction and compared them with latencies from direct muscle strikes and theoretical calculations based on reflex components. Such studies were unable to resolve the reflex issue during the nineteenth century. The physicians were shown to be limited, like all scientific explorers of the unknown, by their knowledge, methodology, and technology.


Assuntos
Nafazolina , Neurologia , Humanos , Neurologia/história , América do Norte , Reflexo , Reflexo de Estiramento/fisiologia
7.
Midwifery ; 109: 103333, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35405404

RESUMO

OBJECTIVE: To identify the challenges and opportunities for rolling out a bespoke model of group antenatal care called Pregnancy Circles (PC) within the National Health Service: what kind of support and training is needed and what adaptations are appropriate, including during a pandemic when face-to-face interaction is limited. DESIGN: Exploratory qualitative study (online focus group). Study co-designed with midwives. Data analysed thematically using an ecological model to synthesise. SETTING: Five maternity services within the National Health Service. PARTICIPANTS: Seven midwives who facilitated PCs. Three senior midwives with implementation experience participated in the co-design process. FINDINGS: Three themes operating across the ecological model were identified: 'Implementing innovation', 'Philosophy of care' and 'Resource management'. Tensions were identified between group care's focus on relationships and professional autonomy, and concepts of efficiency within the NHS's market model of care. Midwives found protected time, training and ongoing support essential for developing the skills and confidence needed to deliver this innovative model of care. Integrating Pregnancy Circles with continuity of carer models was seen as the most promising opportunity for long-term implementation. Midwives perceived continuity and peer support as the most effective elements of the model and there was some evidence that the model may be robust enough to withstand adaptation to online delivery. KEY CONCLUSIONS: Midwives facilitating group care enjoyed the relationships, autonomy and professional development the model offered. Harnessing this personal (micro-level) satisfaction is key to wider implementation. Group care is well aligned with current maternity policy but the challenges midwives face (temporal, practical and cultural) must be anticipated and addressed at macro and meso level for wider implementation to be sustainable. The PC model may be flexible enough to adapt to online delivery and extend continuity of care but further research is needed in these areas. IMPLICATIONS FOR PRACTICE: Implementation of group care in the NHS requires senior leadership and expertise in change management, protected time for training and delivery of the model, and funding for equipment. Training and ongoing support, are vital for sustainability and quality control. There is potential for online delivery and integrating group care with continuity models.


Assuntos
Serviços de Saúde Materna , Tocologia , Obstetrícia , Feminino , Humanos , Gravidez , Cuidado Pré-Natal , Pesquisa Qualitativa , Medicina Estatal
8.
Clin Shoulder Elb ; 24(1): 32-35, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33652510

RESUMO

Angioleiomyoma is a benign soft tissue tumor originating from vascular smooth muscle. We report a case of a 20-year-old student who presented with pain in the right shoulder of 4 years duration. Shoulder movements were pain-free throughout the range of motion except resisted external rotation. Magnetic resonance imaging visualized a well-circumscribed lesion over the infraspinatus tendon. The lesion was surgically removed and sent for histopathological analysis. Morphology and immunohistochemistry results were suggestive of angioleiomyoma. The most common location for such a lesion is the lower limb, with less than 1% being reported in the upper arm, of which an angioleiomyoma of the shoulder is extremely rare.

9.
Am Surg ; 76(12): 1319-20, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21265342

RESUMO

The Greenfield filter was the result of collaboration between a surgeon and a petroleum engineer. Originally it was a component of a catheter management approach to massive pulmonary embolism. Industry support allowed further technical improvements and long-term patient followup studies.


Assuntos
Filtros de Veia Cava/história , Engenharia Biomédica/história , Desenho de Equipamento , História do Século XX , Humanos , Relações Interprofissionais , Embolia Pulmonar/prevenção & controle
10.
Bratisl Lek Listy ; 111(7): 389-91, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20806545

RESUMO

Factors influencing the appropriate time to obturate a tooth are the patient's signs and symptoms, pulp and periradicular status, degree of difficulty, and patient management. The current consensus is that one-step treatment procedures are acceptable in cases where the patient exhibits a vital pulp. The removal of normal or inflamed pulp tissue and performance of the procedure under aseptic conditions should result in a successful outcome because of the absence of bacterial contamination. Obturation at the initial visit also precludes the contamination as a result of leakage during the period between the patient's visits. When patients present with acute symptoms caused by pulp necrosis and acute periradicular abscess, the obturation is generally delayed until the patient is asymptomatic. The interappointment antimicrobial dressing is indicated before the definitive obturation (Ref. 15).


Assuntos
Desinfecção , Irrigantes do Canal Radicular , Obturação do Canal Radicular , Cavidade Pulpar/microbiologia , Humanos
12.
Science ; 247(4939): 189-92, 1990 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-2294601

RESUMO

Experiments are presented that confirm earlier predictions that the mode of supply of reactants to a nonlinear (bio)chemical reaction determines or controls concentrations at steady states far from equilibrium. The oxidation of nicotinamide adenine dinucleotide (NADH) catalyzed by the enzyme horseradish peroxidase with continuous input of oxygen was studied; NAD+ is continuously recycled to NADH through a glucose-6-phosphate dehydrogenase system. A comparison of steady-state concentrations is made with an oscillatory oxygen input and a constant input at the same average oxygen input for both modes. By varying the frequency and amplitude of the perturbation (O2 influx), the following may be changed: the average concentration of NADH; the Gibbs free energy difference delta G of the reactants and products at steady state; the average rate of the reaction; the phase relation between the oscillatory rate and delta G; and the dissipation. These results confirm the possibility of an "alternating current chemistry," of control and optimization of thermodynamic efficiency and dissipation by means of external variation of constraints in classes of nonlinear reactions and biological pumps, and of improvements of the yield in such reactions (heterogeneous catalysis, for example).


Assuntos
Glucosefosfato Desidrogenase/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , NAD/metabolismo , Peroxidases/metabolismo , Trifosfato de Adenosina/metabolismo , Fenômenos Químicos , Química , Cinética , Oxirredução , Oxigênio/metabolismo , Termodinâmica
13.
Science ; 175(4022): 656, 1972 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-4109853

RESUMO

Pepstatin, an N-acylated pentapeptide obtained from culture filtrates of actinomycetes and first characterized as an inhibitor of pepsin, produces inhibition of the renin-substrate reaction both in vitro and in vivo.


Assuntos
alfa-Globulinas/metabolismo , Angiotensina II/metabolismo , Peptídeos/farmacologia , Renina/antagonistas & inibidores , Actinomyces/análise , Animais , Bioensaio , Pressão Sanguínea/efeitos dos fármacos , Peptídeos/isolamento & purificação , Ratos , Suínos
14.
Science ; 262(5132): 404-7, 1993 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17789947

RESUMO

Perfluoroalkylated nanospheres have been prepared by reaction of fullerenes with a variety of fluoroalkyl radicals. The latter are generated by thermal or photochemical decomposition of fluoroalkyl iodides or fluorodiacyl peroxides. Up to 16 radicals add to C(60) to afford easily isolable fluoroalkylated derivatives. The monosubstituted radical adducts were detected by electron spin resonance in the early stages of the fluoroalkylation reactions. These spheroidal molecules are thermally quite stable, soluble in fluoroorganic solvents, chemically resistant to corrosive aqueous solutions, and more volatile than the parent fullerenes. Films of the sublimed material display properties typical for a perfluoroalkylated material.

15.
J Hist Neurosci ; 27(4): 311-332, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29652555

RESUMO

This article shows that the academic and research careers of Henry Herbert Donaldson (1857-1938) were directed to provide basic information about the growth of the vertebrate nervous system and to provide standards and the means to make such research efficient. He earned the reputation of making the albino rat a standard laboratory animal. His academic career began when he was an undergraduate at Yale University in 1875 and concluded with his death as Professor and Head of the Department of Neurology at the Wistar Institute of Anatomy and Biology of the University of Pennsylvania in 1938. During that period, pivotal experiences occurred, including research in physiological chemistry with Chittenden at the Sheffield School at Yale, graduate study at Johns Hopkins University, postgraduate study in Europe, and professorial positions at Clark University and the University of Chicago. It was at Johns Hopkins University that Donaldson learned about the need for physiological, anatomical, and psychophysical research and about the techniques to allow such research. It was at Clark University that he had first-hand and detailed experience with the anatomy of the brain of a deaf-blind-mute woman, as he attempted to correlate her sensory deficits with her brain development. It was at Clark University that he clearly recognized the need for standardization in neurological research. At the University of Chicago, he developed administrative skills and began a coordinated research effort to delimit the growth of the nervous system. It was at Chicago that he learned that the albino rat could be a reasonable subject for such research. It was also at Chicago that he was able to formulate ideas about the future organizational needs of human neuroanatomy. It was at the Wistar Institute that his research program and his professional career matured. He organized a research effort to elucidate the growth of the nervous system. He contributed to the coordination of neurological research in the United States and Europe. It was while at the Wistar Institute that he became well-known for making the albino rat a standard laboratory mammal-a convenient living material for research.


Assuntos
Pesquisa Biomédica/normas , Sistema Nervoso Central , Mamíferos , Neuroanatomia/normas , Animais , História do Século XIX , História do Século XX , Humanos , Neurologia , Ratos , Ratos Wistar
16.
J Hist Neurosci ; 27(2): 145-164, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29595374

RESUMO

Henry Herbert Donaldson (1857-1938) was a leader in neurological research in the United States for several decades, beginning about 1890. A detailed account of three of his earliest publications shows the neuroanatomical procedures involved in the study of the relation of brain and intelligence during the late-nineteenth-century in America. Two of the articles, published in September 1890 and December 1891, were titled, "Anatomical Observations on the Brain and Several Sense-Organs of the Blind Deaf-Mute, Laura Dewy Bridgman (1829-1889)"; the third, published in August 1892, used the information from the first two to delimit the extent of the visual processing area of the human cortex. Donaldson's procedures included brain cuttings and measures of macroscopic brain structures, histology of cellular structures, attempts to relate macroscopic brain structures with brain functions, data corrections, estimations, comparisons, and statistics. These procedures provide a view of the relative thoroughness, accuracy, and comparability of the various neuroanatomical techniques in use at that time and of Donaldson's implementation of the techniques. Donaldson's brain cutting techniques were much more comparable than his measurement techniques. The latter could be quite precise, but they were fraught with lack of standardized procedures that made corrections and estimations necessary when making data comparisons across studies. Donaldson emphasized these incompatibilities, implying a need for standardization. Statistical procedures were the least thorough and effective. His, and the field's, total complement of statistical techniques consisted of mean and range, which severely limited his ability to make complicated assessments. This limitation was not necessarily supplemented by stringent control group comparisons.


Assuntos
Pesquisa Biomédica/normas , Encéfalo/anatomia & histologia , Neuroanatomia/história , Sistema Nervoso Central , Interpretação Estatística de Dados , História do Século XIX , História do Século XX , Humanos , Estados Unidos
17.
J Clin Invest ; 71(5): 1366-74, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6406548

RESUMO

To determine whether the pulmonary vasodilation produced by isoproterenol is mediated solely by its beta adrenergic effects, we studied the hemodynamic responses to isoproterenol in three groups of dogs with pulmonary vasoconstriction produced by continuous ventilation with 10% oxygen: (a) hypoxia alone, (b) hypoxia and propranolol 0.3 mg/kg i.v. bolus followed by an infusion of 5 micrograms/kg per min, and (c) hypoxia after pretreatment with an inhibitor of cyclooxygenase, either indomethacin or meclofenamate 5 mg/kg s.c. twice daily for 2 d prior to study. All groups had similar values for mean pulmonary artery pressure (PAPm) and pulmonary vascular resistance (PVR) during room air and hypoxic ventilation. Isoproterenol in doses of 0.0025, 0.005, and 0.05 micrograms/kg per min produced a dose-related decline in PAPm and PVR during hypoxia in group 1. Despite beta-blockade with propranolol (group 2), isoproterenol at all three doses significantly reduced PAPm and PVR. The responses to isoproterenol were comparable in the presence or absence of propranolol; at 0.05 micrograms/kg per min the effects of isoproterenol were blunted, but not abolished, by propranolol. Similar results were observed even when five times the dose of propranolol was given. Isoproterenol at all three doses had no effect, however, on PAPm and PVR in the cyclooxygenase inhibitor-pretreated group. These data suggest that the pulmonary vasodilator effects of isoproterenol are not mediated solely by pulmonary vascular beta adrenergic receptors, and that vasodilator prostaglandins may play a role in the responses to this drug.


Assuntos
Hipóxia/fisiopatologia , Isoproterenol/farmacologia , Prostaglandinas/fisiologia , Artéria Pulmonar/fisiologia , Vasoconstrição/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase , Cães , Feminino , Hemodinâmica/efeitos dos fármacos , Masculino , Propranolol/farmacologia , Resistência Vascular/efeitos dos fármacos
18.
J Clin Invest ; 67(1): 193-200, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7451649

RESUMO

TO DETERMINE WHETHER HYDRALAZINE, A SYSTEMIC VASODILATOR, EXERTED A SIMILAR EFFECT ON THE PULMONARY CIRCULATION, WE STUDIED THE CIRCULATORY CHANGES IN DOGS DURING THREE INTERVENTIONS: (a) the control state during room air ventilation; (b) during continuous hypoxic ventilation with 10% oxygen, and maintaining continuous hypoxic ventilation; and (c) after 1 mg/kg hydralazine intravenously. Ventilation with 10% oxygen caused the mean pulmonary artery pressure to increase from 10+/-1.2 to 23+/-2.4 mm Hg (P < 0.01) and the pulmonary arteriolar resistance to increase from 1.51+/-0.19 to 5.87+/-1.10 U (P < 0.01). Hydralazine significantly lowered the pulmonary artery pressure (23.0+/-2.4 to 14.3+/-1.5 mm Hg, P < 0.01) and the pulmonary arteriolar resistance (5.87+/-1.10 to 2.87+/-0.52 U, P < 0.01). Femoral artery pressure, pulmonary artery wedge pressure, heart rate, and cardiac output remained unchanged throughout. To ascertain the contribution of the prostaglandin system to the pulmonary vasodilator effects of hydralazine, we pretreated a group of dogs with the prostaglandin synthetase inhibitor, indomethacin, 5 mg/kg s.c., twice daily for 2 d. These animals then underwent identical studies.The pretreated dogs had comparable base-line and hypoxia hemodynamic data. However, hydralazine had no effect on pulmonary artery pressure (23.3+/-1.6 vs. 21.7+/-2.3 mm Hg, NS) or pulmonary arteriolar resistance (8.03+/-1.09 vs. 7.14+/-1.42, NS) during continuous hypoxic ventilation in the indomethacin-pretreated group. Pretreatment with indomethacin did not, however, block the pulmonary vasodilator effects of intravenous prostacyclin (PGI(2)). Pretreatment with meclofenamate, a cyclo-oxygenase inhibitor structurally unrelated to indomethacin, also blocked the effects of hydralazine during hypoxic ventilation. These data suggest that hydralazine exerts a pulmonary vasodilatory effect during hypoxia-induced pulmonary vasoconstriction, and that this vasodilator effect may be mediated by prostaglandins.


Assuntos
Hidralazina/farmacologia , Indometacina/farmacologia , Ácido Meclofenâmico/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Cães , Feminino , Masculino , Oxigênio/fisiologia , Prostaglandinas/fisiologia , Respiração , Resistência Vascular/efeitos dos fármacos
19.
J Hist Neurosci ; 26(2): 154-168, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27379724

RESUMO

This article contrasts two American Physiological Societies, one founded near the beginning of the nineteenth century in 1837 and the other founded near its end in 1887. The contrast allows a perspective on how much budding neuroscience had developed during the nineteenth century in America. The contrast also emphasizes the complicated structure needed in both medicine and physiology to allow neurophysiology to flourish. The objectives of the American Physiological Society of 1887 were (and are) to promote physiological research and to codify physiology as a discipline. These would be accomplished by making physiology much more inclusive than traditionally accepted by raising research standards, by giving prestige to its members, by providing members a source of professional interchange, by protecting its members from antivivisectionists, and by promoting physiology as fundamental to medicine. The quantity of neuroscientific experiments by its members was striking. The main organizers of the society were Silas Weir Mitchell, John Call Dalton, Henry Pickering Bowditch, and Henry Newell Martin. The objective of the American Physiological Society of 1837 was to disperse knowledge of the "laws of life" and to promote human health and longevity. The primary organizers were William Andrus Alcott and Sylvester Graham with the encouragement of John Benson. Its technique was to use physiological information, not create it as was the case in 1887. Its object was to disseminate the word that healthy eating will improve the quality of life.


Assuntos
Neurofisiologia/história , Neurociências/história , História do Século XIX , História do Século XX , Humanos , Sociedades Médicas , Estados Unidos
20.
J Am Coll Surg ; 203(3): 290-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16931300

RESUMO

BACKGROUND: This study describes, quantifies, and evaluates the University of Michigan Department of Surgery medical malpractice experience for the 1992 to 2002 period. The goal is to gain an understanding of what our claims experience has been, what services are highest risk, and where the financial exposure lies. STUDY DESIGN: The study analyzed 308 medical malpractice cases within the Department of Surgery from 1992 through 2002. RESULTS: There were 263 cases involving a single surgical service (defendant-only) and 70 shared cases involving multiple services. One hundred forty-four cases (47%) were settled with no payment to the plaintiff. Settlements for all cases totaled Dollars 38,718,254. The per-case expense (not including legal fees) was Dollars 125,708. Legal expenses for all cases totaled Dollars 5,356,588, averaging Dollars 17,391 per case. CONCLUSIONS: Understanding and sharing institutional data on medical malpractice is critical to developing effective strategies for managing malpractice risk. Although many institutions treat these data as proprietary and confidential, communication of this information generates a better understanding of the opportunities that are available for development and implementation of appropriate risk-management tools.


Assuntos
Imperícia/estatística & dados numéricos , Faculdades de Medicina , Hospitais Universitários , Imperícia/economia , Imperícia/legislação & jurisprudência , Michigan , Gestão de Riscos , Fatores de Tempo
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