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1.
Allergy ; 73(8): 1575-1596, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29318628

RESUMO

Hereditary Angioedema (HAE) is a rare and disabling disease. Early diagnosis and appropriate therapy are essential. This update and revision of the global guideline for HAE provides up-to-date consensus recommendations for the management of HAE. In the development of this update and revision of the guideline, an international expert panel reviewed the existing evidence and developed 20 recommendations that were discussed, finalized and consented during the guideline consensus conference in June 2016 in Vienna. The final version of this update and revision of the guideline incorporates the contributions of a board of expert reviewers and the endorsing societies. The goal of this guideline update and revision is to provide clinicians and their patients with guidance that will assist them in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2). The key clinical questions covered by these recommendations are: (1) How should HAE-1/2 be defined and classified?, (2) How should HAE-1/2 be diagnosed?, (3) Should HAE-1/2 patients receive prophylactic and/or on-demand treatment and what treatment options should be used?, (4) Should HAE-1/2 management be different for special HAE-1/2 patient groups such as pregnant/lactating women or children?, and (5) Should HAE-1/2 management incorporate self-administration of therapies and patient support measures?


Assuntos
Angioedemas Hereditários/diagnóstico , Angioedemas Hereditários/tratamento farmacológico , Doenças Raras/diagnóstico , Doenças Raras/tratamento farmacológico , Adolescente , Adulto , Assistência ao Convalescente , Angioedemas Hereditários/prevenção & controle , Criança , Proteína Inibidora do Complemento C1/genética , Consenso , Feminino , Diretrizes para o Planejamento em Saúde , Humanos , Lactação , Masculino , Medicina de Precisão , Gravidez , Doenças Raras/prevenção & controle , Terminologia como Assunto , Adulto Jovem
2.
Allergy ; 73(9): 1871-1880, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29688579

RESUMO

BACKGROUND: Effective inhibition of plasma kallikrein may have significant benefits for patients with hereditary angioedema due to deficiency of C1 inhibitor (C1-INH-HAE) by reducing the frequency of angioedema attacks. Avoralstat is a small molecule inhibitor of plasma kallikrein. This study (OPuS-2) evaluated the efficacy and safety of prophylactic avoralstat 300 or 500 mg compared with placebo. METHODS: OPuS-2 was a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. Subjects were administered avoralstat 300 mg, avoralstat 500 mg, or placebo orally 3 times per day for 12 weeks. The primary efficacy endpoint was the angioedema attack rate based on adjudicator-confirmed attacks. RESULTS: A total of 110 subjects were randomized and dosed. The least squares (LS) mean attack rates per week were 0.589, 0.675, and 0.593 for subjects receiving avoralstat 500 mg, avoralstat 300 mg, and placebo, respectively. Overall, 1 subject in each of the avoralstat groups and no subjects in the placebo group were attack-free during the 84-day treatment period. The LS mean duration of all confirmed attacks was 25.4, 29.4, and 31.4 hours for the avoralstat 500 mg, avoralstat 300 mg, and placebo groups, respectively. Using the Angioedema Quality of Life Questionnaire (AE-QoL), improved QoL was observed for the avoralstat 500 mg group compared with placebo. Avoralstat was generally safe and well tolerated. CONCLUSIONS: Although this study did not demonstrate efficacy of avoralstat in preventing angioedema attacks in C1-INH-HAE, it provided evidence of shortened angioedema episodes and improved QoL in the avoralstat 500 mg treatment group compared with placebo.


Assuntos
Angioedemas Hereditários/prevenção & controle , Inibidores Enzimáticos/uso terapêutico , Calicreína Plasmática/antagonistas & inibidores , Administração Oral , Adulto , Angioedemas Hereditários/diagnóstico , Angioedemas Hereditários/tratamento farmacológico , Progressão da Doença , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Recidiva , Resultado do Tratamento
3.
J Public Health (Oxf) ; 40(3): 461-466, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28977541

RESUMO

Background: The Cold Weather Plan (CWP) for England was launched by the Department of Health in 2011 to prevent avoidable harm to health by cold weather by enabling individuals to prepare and respond appropriately. This study sought the views of local decision makers involved in the implementation of the CWP in the winter of 2012/13 to establish the effects of the CWP on local planning. It was part of a multi-component independent evaluation of the CWP. Methods: Ten LA areas were purposively sampled which varied in level of deprivation and urbanism. Fifty-two semi-structured interviews were held with health and social care managers involved in local planning between November 2012 and May 2013. Results: Thematic analysis revealed that the CWP was considered a useful framework to formalize working arrangements between agencies though local leadership varied across localities. There were difficulties in engaging general practitioners, differences in defining vulnerable individuals and a lack of performance monitoring mechanisms. Conclusions: The CWP was welcomed by local health and social care managers, and improved proactive winter preparedness. Areas for improvement include better integration with general practice, and targeting resources at socially isolated individuals in cold homes with specific interventions aimed at reducing social isolation and building community resilience.


Assuntos
Temperatura Baixa , Administração de Serviços de Saúde , Seguridade Social , Temperatura Baixa/efeitos adversos , Inglaterra , Medicina Geral/organização & administração , Serviços de Saúde , Humanos , Entrevistas como Assunto , Prática de Saúde Pública , Populações Vulneráveis
7.
Curr Oncol ; 23(1): 42-51, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26966403

RESUMO

Infections are a major cause of morbidity and mortality in patients with chronic lymphocytic leukemia (cll), who typically have increased susceptibility because of hypogammaglobulinemia (hgg) related to their disease and its treatment. Immunoglobulin replacement therapy (igrt) has been shown to reduce the frequency of bacterial infections and associated hospitalizations in patients with hgg or a history of infection, or both. However, use of igrt in cll is contentious. Studies examining such treatment were conducted largely before the use of newer chemoimmunotherapies, which can extend lifespan, but do not correct the hgg inherent to the disease. Thus, the utility of igrt has to be re-evaluated in the current setting. Here, we discuss the evidence for the use of igrt in cll and provide a practical approach to its use in the prevention and management of infections.

8.
Vet Pathol ; 52(6): 1250-3, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25445322

RESUMO

Aleutian disease virus (ADV, Amdovirus, Parvoviridae) primarily infects farmed mustelids (mink and ferrets) but also other fur-bearing animals and humans. Three Aleutian disease (AD) cases have been described in captive striped skunks; however, little is known about the relevance of AD in free-ranging carnivores. This work describes the pathological findings and temporospatial distribution in 7 cases of AD in free-ranging striped skunks. All cases showed neurologic disease and were found in a 46-month period (2010-2013) within a localized geographical region in California. Lesions included multisystemic plasmacytic and lymphocytic inflammation (ie, interstitial nephritis, myocarditis, hepatitis, meningoencephalitis, pneumonia, and splenitis), glomerulonephritis, arteritis with or without fibrinoid necrosis in several organs (ie, kidney, heart, brain, and spleen), splenomegaly, ascites/hydrothorax, and/or encephalomalacia with cerebral microangiopathy. ADV infection was confirmed in all cases by specific polymerase chain reaction and/or in situ hybridization. The results suggest that AD is an emerging disease in free-ranging striped skunks in California.


Assuntos
Vírus da Doença Aleutiana do Vison/isolamento & purificação , Doença Aleutiana do Vison/virologia , Doenças Transmissíveis Emergentes/veterinária , Mephitidae/virologia , Vison/virologia , Vírus da Doença Aleutiana do Vison/genética , Animais , California/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Inflamação/veterinária
9.
Clin Exp Immunol ; 177(2): 544-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749847

RESUMO

Hereditary angioedema (HAE) is characterized by potentially life-threatening recurrent episodes of oedema. The open-label extension (OLE) phase of the For Angioedema Subcutaneous Treatment (FAST)-1 trial (NCT00097695) evaluated the efficacy and safety of repeated icatibant exposure in adults with multiple HAE attacks. Following completion of the randomized, controlled phase, patients could receive open-label icatibant (30 mg subcutaneously) for subsequent attacks. The primary end-point was time to onset of primary symptom relief, as assessed by visual analogue scale (VAS). Descriptive statistics were reported for cutaneous/abdominal attacks 1-10 treated in the OLE phase and individual laryngeal attacks. Post-hoc analyses were conducted in patients with ≥ 5 attacks across the controlled and OLE phases. Safety was evaluated throughout. During the OLE phase, 72 patients received icatibant for 340 attacks. For cutaneous/abdominal attacks 1-10, the median time to onset of primary symptom relief was 1·0-2·0 h. For laryngeal attacks 1-12, patient-assessed median time to initial symptom improvement was 0·3-1·2 h. Post-hoc analyses showed the time to onset of symptom relief based on composite VAS was consistent across repeated treatments with icatibant. One injection of icatibant was sufficient to treat 88·2% of attacks; rescue medication was required in 5·3% of attacks. No icatibant-related serious adverse events were reported. Icatibant provided consistent efficacy and was well tolerated for repeated treatment of HAE attacks.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Bradicinina/análogos & derivados , Adulto , Angioedemas Hereditários/diagnóstico , Bradicinina/administração & dosagem , Bradicinina/efeitos adversos , Bradicinina/uso terapêutico , Antagonistas dos Receptores da Bradicinina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retratamento , Resultado do Tratamento , Adulto Jovem
10.
Haemophilia ; 20(4): e251-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24948405

RESUMO

The Canadian Hemophilia Assessment and Resource Management System (CHARMS) tracks factor concentrates (FC) from the sole suppliers, Canadian Blood Services (CBS) and Hema-Quebec (HQ), to hospitals and to patients' homes. Patients FC infusion data are entered into CHARMS at Canadian Hemophilia Treatment Centres (HTCs) then exported to the national database (CentrePoint). From 2000 to 2009, 2260 registered haemophilia A or B patients received FVIII (1,009,097,765 IU) and FIX (272,406,859 IU). Over 91% of FVIII and over 84% of FIX was infused at home. Utilization of FVIII progressively increased; this was accounted for by an increase in the number of patients treated (r = 0.97; P < 0.001), there being a linear relationship between the increase in utilization and the increase in number of patients treated (P < 0.001). There was also a correlation with the annual amount used per patient (r = 0.95; P < 0.001). Utilization of FIX did not increase over time. The highest proportional utilization of both FVIII and FIX was for prophylaxis, and this proportion progressively increased being, in year 10 (2009), 77% and 66% for FVIII and FIX respectively. The proportion used for bleeding remained steady; in year 10 that proportion was 14% for FVIII and 26% for FIX, the use per patient for bleeding decreasing. The HTC-based CHARMS tracking system is essential, in Canada, for analysing indications for infusion, for predicting utilization and planning for future needs.


Assuntos
Fatores de Coagulação Sanguínea/uso terapêutico , Recursos em Saúde/estatística & dados numéricos , Recursos em Saúde/tendências , Hemofilia A/tratamento farmacológico , Fatores de Coagulação Sanguínea/administração & dosagem , Canadá , Feminino , Humanos , Masculino
11.
Science ; 162(3860): 1394-5, 1968 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-5699655

RESUMO

Lidocaine and dibucaine are more effective in neutral than in alkaline solution when tested on the nonmyelinated fibers of the desheathed vagus nerve of the rabbit. Procaine, however, is more effective in alkaline solution. The activity of benzocaine is unaffected by pH. Both the charged and uncharged forms of local anesthetics thus seem capable of blocking conduction.


Assuntos
Dibucaína/farmacologia , Concentração de Íons de Hidrogênio , Lidocaína/farmacologia , Condução Nervosa/efeitos dos fármacos , Neurônios/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Benzocaína/farmacologia , Fenômenos Químicos , Físico-Química , Depressão Química , Técnicas In Vitro , Coelhos , Nervo Vago
12.
Avian Dis ; 63(3): 531-538, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31967440

RESUMO

In this case report, we describe the pathologic changes and the ultrastructural and molecular characteristics of an adenovirus in a sun conure (Aratinga solstitialis) that presented with a history of sudden death. On histologic examination, there was multifocal hepatic and splenic necrosis. Within some hepatocytes and unidentified cells in the spleen, renal interstitial fibroblasts, and ovarian stroma were intranuclear amphophilic inclusion bodies. Electron microscopy of affected tissue showed intranuclear icosahedral viral particles with an inner capsid (29.2-33.8 nm in diameter) and an outer capsid (70.2-71.7 nm in diameter). Next-generation sequencing and BLAST analysis of complementary DNA synthesized from RNA extracted from formalin-fixed tissues showed an adenovirus, designated sun conure adenovirus (SCAdv). A DNA in situ hybridization (ISH) probe, constructed from the SCAdv and similar sequences from GenBank, was also positive in the intranuclear inclusion bodies, whereas standard ISH for psittacine adenovirus 1 was negative. These results show that ancillary diagnostic testing, such as next-generation sequencing, even using formalin-fixed, paraffin-embedded tissues, along with ISH, can be useful in identifying additional, unknown viruses that show similar pathology to commonly known viruses but do not show up as positive on routine diagnostic tests.


Reporte de caso- Cambios histopatológicos, ultraestructura y caracterización molecular de un adenovirus en una cotorra solar (Aratinga solstitialis). En este reporte de caso, se describen los cambios patológicos y las características ultraestructurales y moleculares de un adenovirus en una cotorra solar (Aratinga solstitialis) que se presentó con un historial de muerte súbita. En el examen histológico, hubo necrosis hepática y esplénica multifocal. Dentro de algunos hepatocitos y células no identificadas en el bazo, los fibroblastos intersticiales renales y en el estroma ovárico se encontraron cuerpos de inclusión anfofílicos intranucleares. La microscopía electrónica del tejido afectado mostró partículas víricas intranucleares icosaédricas con una cápside interna (de 29.2 a 33.8 nm de diámetro) y una cápside externa (de 70.2 a 71.7 nm de diámetro). Mediante el análisis de secuenciación de segunda generación y por la Herramienta de Búsqueda de Alineaciones Local Básica (con siglas en inglés BLAST) del ADN complementario sintetizado a partir de ARN extraído de tejidos fijados con formalina mostraron un adenovirus, denominado adenovirus de cotorra solar (SCAdv). Se construyó una sonda de ADN para hibridación in situ (ISH), a partir de la secuencia del virus SCAdv y de secuencias similares de GenBank, que generó reacción positiva en los cuerpos de inclusión intranucleares, mientras que la hibridación in situ estándar para el adenovirus I de psitácidos fue negativa. Estos resultados muestran que las pruebas de diagnóstico complementarias, como la secuenciación de segunda generación, utilizando tejidos fijados con formalina e incluidos en parafina junto con la hibridación in situ pueden ser útiles para identificar virus adicionales desconocidos que muestran una patología similar a los virus comúnmente conocidos, pero que no se detectan con las pruebas diagnósticas de rutina.


Assuntos
Infecções por Adenoviridae/veterinária , Doenças das Aves/patologia , Papagaios , Siadenovirus/isolamento & purificação , Infecções por Adenoviridae/patologia , Infecções por Adenoviridae/virologia , Animais , Sequência de Bases , Doenças das Aves/virologia , Proteínas do Capsídeo/análise , Evolução Fatal , Feminino , Filogenia , Alinhamento de Sequência , Siadenovirus/genética
14.
Thromb Res ; 152: 44-48, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28222322

RESUMO

The reversal of dabigatran-associated major bleeding can now be achieved with the antidote idarucizumab. We evaluated activated prothrombin complex concentrate (aPCC) as an alternative for this purpose. Patients treated with dabigatran and suffering a major bleed were treated as per existing hospital protocol with aPCC. They were subsequently recruited for a 30-day follow-up. Effectiveness was evaluated by the treating physician, using an Assessment Guide. Safety outcomes were arterial or venous thromboembolism or death. A comparison was also made with historic cases with dabigatran-associated major bleeds treated with supportive care, by matching 1:2 for type of bleed, age and sex. We aimed at 32 evaluable cases but the study was prematurely discontinued after 14 cases due to the availability of the approved antidote. The effectiveness of aPCC was assessed as Good in 9 (64%), moderate in 5 (36%) and poor in none. There were no thromboembolic events and one death. In the secondary adjudication of effectiveness, using the same criteria and by the same adjudicators as previously done for the historic cases, the outcome was graded for the current cases versus the historic cases as Good, Moderate, or Poor in 10 (71%) versus 16 (57%), 3 (21%) versus 4 (14%), and 1 (7%) versus 8 (29%), respectively. Although supportive care is sufficient to manage many patients with dabigatran-associated bleeding, aPCC might provide an additional benefit to control life-threatening bleeding in selected cases and does not appear to cause an excess of thromboembolic events.


Assuntos
Antitrombinas/efeitos adversos , Fatores de Coagulação Sanguínea/uso terapêutico , Dabigatrana/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/sangue , Fibrilação Atrial/tratamento farmacológico , Coagulação Sanguínea/efeitos dos fármacos , Feminino , Hemorragia/sangue , Humanos , Masculino , Estudos Prospectivos
15.
Cancer Res ; 52(22): 6194-9, 1992 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1423262

RESUMO

We present here an analysis of the spectrum of mutations of the p53 gene seen in 127 bone and soft tissue sarcomas of various histological classifications. Gross rearrangements were analyzed by Southern blotting using a complementary DNA probe from the p53 gene, and subtle alterations in the entire coding sequence (exons 2 through 11) were identified by a combination of single-strand conformation polymorphism analysis and direct genomic sequencing. A total of 42 somatic alterations of the p53 gene were found, of which 21 were gross rearrangements and 21 were subtle alterations. These included 17 cases of a single base substitution, 3 small deletions, and one single base insertion. In contrast to reported findings for other types of cancer, we found that mutations of the p53 gene in sarcomas are quite heterogeneous both in their distribution throughout the gene and in the type of genetic alterations that result. All 13 missense mutations we found occurred at highly conserved residues, whereas 8 nonsense mutations occurred at sites that spanned the gene from codons 46 to 316. Surprisingly, approximately one-half of the osteosarcomas with allelic deletions on 17p did not have detectable alterations in the coding sequence of the p53 gene.


Assuntos
Neoplasias Ósseas/genética , Genes p53/genética , Osteossarcoma/genética , Sarcoma/genética , Neoplasias de Tecidos Moles/genética , Alelos , Sequência de Bases , Southern Blotting , Éxons/genética , Deleção de Genes , Rearranjo Gênico/genética , Humanos , Dados de Sequência Molecular , Mutação , Fenótipo
16.
BMC Hematol ; 16: 13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27158500

RESUMO

BACKGROUND: This study was undertaken to explore the longitudinal patterns of health-related quality of life (HRQoL) among youth and young adults with Hemophilia A (HA) over a 3-year period. This report presents the baseline characteristics of the study cohort. METHODS: Males, 14 to 29 years of age, with predominantly severe HA were recruited from six treatment centres in Canada. Subjects completed a comprehensive survey. HRQoL was measured using: the CHO-KLAT2.0 (youth), Haemo-QoL-A (young adults) and the SF-36v2 (all). RESULTS: 13 youth (mean age = 15.7, range = 12.9-17.9 years) and 33 young adults (mean age = 23.6; range = 18.4 -28.7 years) with moderate (7 %) and severe (93 %) HA were enrolled. All were on a prophylactic regimen with antihemophilic factor (Helixate FS®) during the study. The youth had minimal joint damage (mean HJHS = 5.2) compared to young adults (mean HJHS = 13.3). The mean HRQoL scores for youth were: 79.2 (SD = 11.9) for the CHO-KLAT, and 53.0 (5.5) and 52.3 (6.8) for the SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores respectively. The mean HRQoL scores for young adults were: 85.8 (9.5) for the Haemo-Qol-A, and 50.8 (6.4) and 50.9 (8.8) for PCS and MCS respectively. PCS and MCS scores were comparable to published Canadian norms, however significant differences were found for the domains of Physical Functioning and Bodily Pain. The disease-specific HRQoL scores were weakly correlated with the PCS for youth (CHO-KLAT vs. PCS r = 0.28, p = 0.35); and moderately correlated for the MCS (r = 0.39, p = 0.19). Haemo-QoL-A scores for young adults were strongly correlated with the PCS (r = 0.53, p = 0.001); and weakly correlated with the MCS (r = 0.26, p = 0.13). Joint status as assessed by HJHS was correlated with PCS scores. A history of lifelong prophylaxis resulted in better PCS but worse MCS scores. CONCLUSION: Despite having hemophilia, the youth in this cohort have minimal joint disease and good HRQoL. The young adults demonstrated more joint disease and slightly worse HRQoL in the domains of physical functioning and pain. The data presented here provide new information to inform the selection of Health Related Quality of Life (HRQoL) instruments for use in future clinical trials involving persons with hemophilia. TRIAL REGISTRATION: ClinicalTrials.gov : NCT01034904. Study funded by CSL Behring Canada.

17.
J Immunol Methods ; 201(2): 207-14, 1997 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-9050942

RESUMO

To define the molecular regulation of mast cell phenotype and function optimized procedures must be available to study mRNA from mast cells freshly isolated from tissues. However, rat peritoneal mast cells (PMC) contain large amounts of the proteoglycan heparin, and unfortunately, this molecule which is a potent inhibitor of reverse transcriptase (RT) and Taq polymerase and thus RT-PCR, copurifies with RNA. Here we describe an optimized protocol for extracting and amplifying RNA from rat PMC. Mast cells were isolated from rat peritoneum and a method modified from that of Chomczynski and Sacchi (1987) was used to extract the RNA. Following the removal of heparin by heparinase digestion, first strand cDNA synthesis was primed with oligo-dT and the resulting cDNA was quantified by rapid paper chromatography. The use of a detection system for the reverse transcription reaction ensured that the production of cDNA had occurred and allowed subsequent PCR testing to be optimal. cDNA thus produced can be used to detect relatively specific (histidine decarboxylase) and non-specific (beta-actin) mast cell products. Our PCR studies have shown a 300-fold increase in sensitivity over RNA processed by other methods.


Assuntos
Mastócitos/química , RNA Mensageiro/isolamento & purificação , Animais , Células Cultivadas , Heparina/análise , Heparina Liase , Masculino , Métodos , Cavidade Peritoneal/citologia , Reação em Cadeia da Polimerase/métodos , Polissacarídeo-Liases/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Thromb Haemost ; 83(3): 387-91, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10744141

RESUMO

To determine whether the factor V Leiden mutation is associated with decreased bleeding in individuals with severe hemophilia A, factor concentrate utilization, maximum annual number of bleeding episodes, and the prevalence of hemophilic arthropathy between carriers and non-carriers of the factor V Leiden mutation were compared. Heterozygosity for the factor V Leiden mutation was found in 6 of 137 subjects (4.4%). Carriers of the factor V Leiden mutation utilized less factor concentrate (geometric mean: 310 vs. 1185 units/kg/year) and had fewer bleeding episodes than non-carriers (proportion with 10 or fewer bleeding episodes in their worst year: 50 vs. 11%). However, the factor V Leiden mutation was not associated with the absence of arthropathy. The intron 22 inversion mutation of the factor VIII gene was tested for in a subgroup of 80 subjects, but it was not found to be a significant variable for any of the bleeding endpoints. The results of this small study are consistent with the hypothesis that the factor V Leiden mutation imparts a protective effect; however, a larger confirmatory study in which the factor VIII molecular defects can be controlled for is needed. Furthermore, most severe hemophiliacs who used fewer than 200 units/kg/year of factor concentrate or who had experienced 10 or fewer bleeding episodes per year did not carry the factor V Leiden mutation, suggesting that the proportion of severe hemophiliacs whose mild clinical course can be attributed to the factor V Leiden mutation is small.


Assuntos
Fator V/genética , Hemofilia A/genética , Mutação Puntual , Adolescente , Adulto , Criança , Pré-Escolar , Fator VIII/genética , Fator VIII/uso terapêutico , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Heterozigoto , Humanos , Masculino , Fenótipo
19.
Br J Pharmacol ; 116(5): 2457-67, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8581285

RESUMO

1. The effect of the nitric oxide synthase inhibitor, NG-nitro-L-arginine (L-NOARG), on endothelium-dependent relaxation to a receptor-independent agent, ionomycin, was examined in isolated pulmonary arteries and veins from control, short-term and chronic pulmonary hypertensive sheep. All vessel segments were contracted to optimal levels of active force with endothelin-1 to record endothelium-dependent relaxation. 2. Pulmonary hypertension was induced by continuous pulmonary artery air embolization for 1 day (short-term) and 14 days (chronic) and was associated with a 2 and 3 fold increase in pulmonary vascular resistance respectively. 3. L-NOARG (0.1 mM) reduced the maximum relaxation (Rmax) to ionomycin in large and medium-sized pulmonary arteries from control sheep by approximately 70%. By contrast, L-NOARG (0.1 mM) did not inhibit the Rmax to ionomycin in matched vessels from short-term and chronic pulmonary hypertensive sheep. 4. Resistance of ionomycin-induced relaxations to inhibition by L-NOARG, was confined to the arterial vasculature in chronic pulmonary hypertensive animals, as relaxations to ionomycin in large and medium-sized chronic pulmonary hypertensive veins were, like those in control veins, abolished by L-NOARG. Both large and medium-sized pulmonary veins from short-term pulmonary hypertensive sheep, however, were resistant to block by L-NOARG. 5. Neither sensitivity (pEC50) nor Rmax to ionomycin in large, short-term pulmonary hypertensive arteries was affected when the extracellular concentration of K+ was increased isotonically to 30 mM. Nifedipine (0.3 microM) was present throughout to prevent high K(+)-induced smooth muscle contraction. In the presence of this high extracellular K+, however, L-NOARG (0.1 mM) caused complete inhibition of the relaxation to ionomycin, whereas in normal extracellular K+ (4.7 mM), L-NOARG only weakly inhibited ionomycin relaxations. 6. In conclusion, the onset of pulmonary hypertension in sheep following air embolization, is associated with the development of resistance of endothelium-dependent relaxations to block by L-NOARG. The mechanism of L-NOARG resistance appears to be due to the up-regulation of a K+ channel-mediated backup vasodilator mechanism which can compensate for the loss of nitric oxide (NO)-mediated relaxation. Although this mechanism remains functionally 'silent' in the presence of NO it is able to maintain adequate endothelium-dependent vasodilatation during pulmonary hypertension if NO synthesis is compromised.


Assuntos
Arginina/análogos & derivados , Endotélio Vascular/fisiologia , Inibidores Enzimáticos/farmacologia , Hipertensão Pulmonar/fisiopatologia , Músculo Liso Vascular/fisiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Arginina/farmacologia , Gasometria , Endotélio Vascular/efeitos dos fármacos , Feminino , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , Ionomicina/farmacologia , Ionóforos/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Nitroarginina , Nitroprussiato/farmacologia , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/metabolismo , Cloreto de Potássio/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/fisiologia , Veias Pulmonares/efeitos dos fármacos , Veias Pulmonares/fisiologia , Ovinos , Regulação para Cima/efeitos dos fármacos , Vasodilatadores/farmacologia
20.
J Exp Psychol Gen ; 121(4): 429-34, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1431737

RESUMO

1. The original rough formulation of the expectancy theory is difficult to distinguish from the alternative stimulus-response doctrines. Part of this difficulty results from the fact that implicit in this rough formulation, is a definition of the matrix "x expects a goal at location L," which makes it equivalent to the matrix "x runs down the practiced path," when certain conditions are fulfilled. Because of this difficulty, we have rejected this definition. 2. We have suggested instead a definition of the matrix "x expects a goal at location L" which makes it equivalent to the matrix "x runs down the path which points directly to the location L," when certain conditions are fulfilled. 3. To determine whether rats will run down such a path, whenever the original path is blocked, we have run 56 female rats in a situation which conformed to these conditions. 4. Thirty-six percent of the rats chose the path which pointed directly towards the location of the goal. The remaining rats were distributed over the other paths in a chance fashion. 5. We have concluded (1) that rats do learn to expect goals in specific locations, (2) that there are important similarities between this behavior and human symbolic behavior, and (3) that these similarities justify our using the word 'expectation' as a name for the disposition to short-cut when the original patch is blocked.


Assuntos
Rememoração Mental , Motivação , Orientação , Resolução de Problemas , Animais , Feminino , História do Século XX , Ratos , Estados Unidos
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