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1.
Int J Cardiol ; 405: 131940, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458385

RESUMO

BACKGROUND: As life expectancy increases, the population of older individuals with coronary artery disease and frailty is growing. We aimed to assess the impact of patient-reported frailty on the treatment and prognosis of elderly early survivors of non-ST-elevation acute coronary syndrome (NSTE-ACS). METHODS: Frailty data were obtained from two prospective trials, POPular Age and the POPular Age Registry, which both assessed elderly NSTE-ACS patients. Frailty was assessed one month after admission with the Groningen Frailty Indicator (GFI) and was defined as a GFI-score of 4 or higher. In these early survivors of NSTE-ACS, we assessed differences in treatment and 1-year outcomes between frail and non-frail patients, considering major adverse cardiovascular events (MACE, including cardiovascular mortality, myocardial infarction, and stroke) and major bleeding. RESULTS: The total study population consisted of 2192 NSTE-ACS patients, aged ≥70 years. The GFI-score was available in 1320 patients (79 ± 5 years, 37% women), of whom 712 (54%) were considered frail. Frail patients were at higher risk for MACE than non-frail patients (9.7% vs. 5.1%, adjusted hazard ratio [HR] 1.57, 95% confidence interval [CI] 1.01-2.43, p = 0.04), but not for major bleeding (3.7% vs. 2.8%, adjusted HR 1.23, 95% CI 0.65-2.32, p = 0.53). Cubic spline analysis showed a gradual increase of the risk for clinical outcomes with higher GFI-scores. CONCLUSIONS: In elderly NSTE-ACS patients who survived 1-month follow-up, patient-reported frailty was independently associated with a higher risk for 1-year MACE, but not with major bleeding. These findings emphasize the importance of frailty screening for risk stratification in elderly NSTE-ACS patients.


Assuntos
Síndrome Coronariana Aguda , Idoso Fragilizado , Fragilidade , Humanos , Idoso , Feminino , Masculino , Fragilidade/epidemiologia , Fragilidade/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Idoso de 80 Anos ou mais , Estudos Prospectivos , Idoso Fragilizado/estatística & dados numéricos , Sistema de Registros , Medidas de Resultados Relatados pelo Paciente , Seguimentos , Resultado do Tratamento , Infarto do Miocárdio sem Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio sem Supradesnível do Segmento ST/mortalidade
2.
Eur Heart J Cardiovasc Pharmacother ; 9(8): 701-708, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37653447

RESUMO

BACKGROUND: Guidelines recommend extended dual antiplatelet therapy, including ticagrelor 60 mg twice daily, in high-risk post-myocardial infarction (MI) patients who have tolerated 12 months and are not at high bleeding risk. The real-world utilization and bleeding and ischaemic outcomes associated with long-term ticagrelor 60 mg in routine clinical practice have not been well described. METHODS: Register and claims data from the USA (Optum Clinformatics, IBM MarketScan, and Medicare) and Europe (Sweden, Italy, UK, and Germany) were extracted. Patients initiating ticagrelor 60 mg ≥12 months after MI, meeting eligibility criteria for the PEGASUS-TIMI (Prevention of Cardiovascular Events in Patients with Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin - Thrombolysis in Myocardial Infarction 45) 54 trial, were included. The cumulative incidence of the composite of MI, stroke, or all-cause mortality and that of bleeding requiring hospitalization were calculated. Meta-analyses were performed to combine estimates from each source. RESULTS: A total of 7035 patients treated with ticagrelor 60 mg met eligibility criteria. Median age was 67 years and 29% were females; 12% had a history of multiple MIs. The majority (95%) had been treated with ticagrelor 90 mg prior to initiating ticagrelor 60 mg. At 12 months from initiation of ticagrelor 60 mg, the cumulative incidence [95% confidence interval (CI)] of MI, stroke, or mortality was 3.33% (2.73-4.04) and was approximately three-fold the risk of bleeding (0.96%; 0.69-1.33). CONCLUSIONS: This study provides insights into the use of ticagrelor 60 mg in patients with prior MI in clinical practice. Observed event rates for ischaemic events and bleeding generally align with those in the pivotal trials, support the established safety profile of ticagrelor, and highlight the significant residual ischaemic risk in this population.Clinical Trials.gov Registration NCT04568083.


Assuntos
Infarto do Miocárdio , Acidente Vascular Cerebral , Estados Unidos/epidemiologia , Feminino , Humanos , Idoso , Masculino , Ticagrelor/efeitos adversos , Inibidores da Agregação Plaquetária , Antagonistas do Receptor Purinérgico P2Y , Adenosina/efeitos adversos , Prevenção Secundária , Medicare , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Isquemia/tratamento farmacológico
3.
Scand J Med Sci Sports ; 26(12): 1480-1489, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26681553

RESUMO

The proximal musculo-tendinous junction (MTJ) is a common site of hamstring strain injury but the anatomy of this region is not well defined. A morphometric analysis of the proximal MTJs of biceps femoris long head (BFlh), semitendinosus (ST), and semimembranosus (SM) was undertaken from dissection of 10 thighs from five male cadavers and magnetic resonance imaging of 20 thighs of 10 active young men. The length, volume, and cross-sectional area of the proximal tendon, MTJ and muscle belly, and muscle-tendon interface area were calculated. In both groups, MTJs were reconstructed three-dimensionally. The proximal tendons and MTJs were expansive, particularly within SM and BFlh. Morphology varied between muscles although length measurements within individual muscles were similar in cadavers and young men. Semimembranosus had the longest proximal tendon (cadavers: mean 33.6 ± 2.0 cm; young men: mean 31.7 ± 1.6 cm) and MTJ (>20 cm in both groups) and the greatest muscle-tendon interface area, followed by BFlh and ST. Mean muscle belly volumes were more than three times greater in young men than elderly male cadavers (P < 0.001). These unique morphometric data contribute to a better understanding of hamstring anatomy, an important factor in the pathogenesis of hamstring strain injury.


Assuntos
Músculos Isquiossurais/diagnóstico por imagem , Tendões dos Músculos Isquiotibiais/diagnóstico por imagem , Adulto , Idoso , Cadáver , Músculos Isquiossurais/anatomia & histologia , Tendões dos Músculos Isquiotibiais/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Adulto Jovem
4.
Heart ; 101(2): 119-25, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25227704

RESUMO

OBJECTIVE: To investigate the cost effectiveness of ticagrelor versus clopidogrel in patients with acute coronary syndromes (ACS) in the Platelet Inhibition and Patient Outcomes (PLATO) study who were scheduled for non-invasive management. METHODS: A previously developed cost effectiveness model was used to estimate long-term costs and outcomes for patients scheduled for non-invasive management. Healthcare costs, event rates and health-related quality of life under treatment with either ticagrelor or clopidogrel over 12 months were estimated from the PLATO study. Long-term costs and health outcomes were estimated based on data from PLATO and published literature sources. To investigate the importance of different healthcare cost structures and life expectancy for the results, the analysis was carried out from the perspectives of the Swedish, UK, German and Brazilian public healthcare systems. RESULTS: Ticagrelor was associated with lifetime quality-adjusted life-year (QALY) gains of 0.17 in Sweden, 0.16 in the UK, 0.17 in Germany and 0.13 in Brazil compared with generic clopidogrel, with increased healthcare costs of €467, €551, €739 and €574, respectively. The cost per QALY gained with ticagrelor was €2747, €3395, €4419 and €4471 from a Swedish, UK, German and Brazilian public healthcare system perspective, respectively. Probabilistic sensitivity analyses indicated that the cost per QALY gained with ticagrelor was below conventional threshold values of cost effectiveness with a high probability. CONCLUSIONS: Treatment of patients with ACS scheduled for 12 months' non-invasive management with ticagrelor is associated with a cost per QALY gained below conventional threshold values of cost effectiveness compared with generic clopidogrel. TRIAL REGISTRATION NUMBER: NCT000391872.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Adenosina/análogos & derivados , Ticlopidina/análogos & derivados , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/economia , Síndrome Coronariana Aguda/psicologia , Adenosina/economia , Adenosina/uso terapêutico , Brasil , Clopidogrel , Análise Custo-Benefício , Gerenciamento Clínico , Eletrocardiografia , Feminino , Alemanha , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Cadeias de Markov , Avaliação de Resultados em Cuidados de Saúde , Inibidores da Agregação Plaquetária/economia , Inibidores da Agregação Plaquetária/uso terapêutico , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Prevenção Secundária/economia , Prevenção Secundária/métodos , Suécia , Ticagrelor , Ticlopidina/economia , Ticlopidina/uso terapêutico , Reino Unido
7.
Thromb Haemost ; 109(5): 817-24, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23467639

RESUMO

The essential role of platelets in haemostasis underlies the relationship between platelet function and spontaneous or procedure-related bleeding, which has important prognostic implications. Although not routinely undertaken, platelet function testing offers the potential to tailor antiplatelet therapy for individual patients. However, uncertainties remain about how well platelet function testing may predict haemostasis and guide management of bleeding risk. Studies of aspirin, P2Y12 inhibitors and other antiplatelet drugs clearly demonstrate how inhibition of platelet function increases bleeding risk. More potent antiplatelet drugs are associated with higher bleeding rates, consistent with the levels of platelet inhibition achieved by these drugs. Studies of patients treated with clopidogrel, which is associated with wide inter-individual variation in antiplatelet effect, suggest that platelet function testing may predict bleeding risk related to coronary artery bypass grafting (CABG) surgery and potentially guide the timing of surgery following discontinuation of clopidogrel. Similarly, some studies have demonstrated a relationship between clopidogrel response and bleeding in patients undergoing percutaneous coronary intervention (PCI), although other studies have not supported this. Carriage of the *17 allele of cytochrome P450 2C19, which is associated with gain of function and enhanced response to clopidogrel, seems to be associated with increased bleeding risk, although studies showing lack of apparent effect of loss-of-function alleles provide contradictory evidence. Further large studies are needed to guide best practice in the application of platelet function testing in the clinical management of patients treated with antiplatelet drugs in order to optimise individual care.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Hemorragia/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Testes de Função Plaquetária , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Hemorragia/sangue , Hemorragia/prevenção & controle , Hemostasia/efeitos dos fármacos , Humanos , Farmacogenética , Hemorragia Pós-Operatória/sangue , Hemorragia Pós-Operatória/induzido quimicamente , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco
9.
Colorectal Dis ; 15(5): 536-43, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23067005

RESUMO

AIM: Neoadjuvant chemotherapy may have a role in the management of colonic carcinoma but clinical trials are required to determine whether this approach is superior to the standard policy of radical surgery, high-quality histopathology and selective postoperative chemotherapy. The selection of appropriate patients for such trials will depend on accurate locoregional staging of disease by preoperative CT scanning. We studied the outcome after radical right hemicolectomy and assessed the accuracy of preoperative CT scans in the prediction of postoperative pathology. METHOD: A retrospective analysis of right hemicolectomies performed with curative intent for colon cancer under the care of a single colorectal surgeon (D.J.A.) was performed. Preoperative CT-proven Dukes D patients were excluded. Patient demographics, postoperative histology, use of adjuvant chemotherapy and survival data were collected. Kaplan-Meier curves were constructed and log-rank testing was performed to compare cancer-specific survival. Fifty patients had their preoperative CT scan images reviewed by two radiologists both blinded to the results of the postoperative histology. The accuracy of preoperative CT for T and N staging was studied. A P-value of < 0.05 was significant. RESULTS: There were 136 patients (79 women). Median age was 76 (interquartile ratio 67-82) years. Median period of follow-up was 72 (interquartile ratio 39-92) months. There were 56 deaths (39 medical, 16 oncological and 1 postoperative). There were three groups of patients: node negative (n = 84), node positive with postoperative adjuvant chemotherapy (n = 30) and node positive without chemotherapy (n = 22). Five-year cancer-specific survival for node negative disease was 84% and was poorer for node positive patients who received adjuvant chemotherapy when compared with those who did not (62 vs 72%, P-value = 0.046 on log-rank testing). Sensitivity, specificity, positive and negative predictive value of CT scan for tumour (T) stage were 90, 33, 86 and 43% respectively, while that for nodal (N) stage was 83, 38, 57 and 69%, respectively. CONCLUSION: CT scan has limited accuracy in predicting those patients with advanced locoregional disease who might benefit from neoadjuvant treatment. When this finding is combined with relatively high cancer-specific survival with surgery alone the impact of adjuvant chemotherapy on survival after radical surgery for right colon carcinoma may be marginal.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Colectomia , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/patologia , Tomografia Computadorizada por Raios X , Adenocarcinoma/terapia , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Colo Ascendente/patologia , Colo Transverso/patologia , Neoplasias do Colo/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Retrospectivos , Taxa de Sobrevida
10.
Theor Appl Genet ; 126(3): 847-65, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23224381

RESUMO

Fruit from Rubus species are highly valued for their flavor and nutritive qualities. Anthocyanin content contributes to these qualities, and although many studies have been conducted to identify and quantify the major anthocyanin compounds from various Rubus species, the genetic control of the accumulation of these complex traits in Rubus is not yet well understood. The identification of the regions of the genome involved in the production of anthocyanins is an important first step in identifying the genes underlying their expression. In this study, ultra and high-performance liquid chromatography (UHPLC and HPLC) and two newly developed Rubus linkage maps were used to conduct QTL analyses to explore the presence of associations between concentrations of five anthocyanins in fruit and genotype. In total, 27 QTL were identified on the Rubus linkage maps, four of which are associated with molecular markers designed from transcription factors and three of which are associated with molecular markers designed from anthocyanin biosynthetic pathway candidate genes. The results of this study suggest that, while QTL for anthocyanin accumulation have been identified on six of seven Rubus linkage groups (RLG), the QTL on RLG2 and RLG7 may be very important for genetic control of cyanidin modification in Rubus.


Assuntos
Antocianinas/análise , Frutas/genética , Genes de Plantas , Locos de Características Quantitativas , Rosaceae/genética , Cromatografia Líquida de Alta Pressão , Mapeamento Cromossômico , Epistasia Genética , Frutas/química , Ligação Genética , Marcadores Genéticos , Fenótipo , Rosaceae/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
J Thromb Haemost ; 9(9): 1730-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21707911

RESUMO

BACKGROUND: The rate of recovery of platelet function after discontinuation of P2Y(12) inhibitors depends on the reversibility of the antiplatelet effect and the extent of the on-treatment response. P2Y(12) inhibition increases the bleeding risk in patients requiring surgery. OBJECTIVES: To evaluate recovery of platelet function after discontinuation of ticagrelor vs. clopidogrel in stable coronary artery disease (CAD) patients with high levels of platelet inhibition (HPI) during the ONSET/OFFSET study. METHODS: Patients received aspirin 75-100 mg per day and either ticagrelor 90 mg twice-daily or clopidogrel 75 mg daily for 6 weeks. This subanalysis included patients with HPI after the last dose of maintenance therapy, defined as: inhibition of platelet aggregation (IPA) > 75% 4 h post-dose (ADP 20 µm, final extent); < 120 P2Y(12) reaction units 8 h post-dose (VerifyNow P2Y(12) assay); or platelet reactivity index < 50% 8 h post-dose (VASP-P assay). RESULTS: IPA > 75% was observed in 39 out of 47 ticagrelor-treated and 17 out of 44 clopidogrel-treated patients. The rate of offset of IPA over 4-72 h was greater with ticagrelor (IPA %/hour slope: -1.11 vs. -0.67 for clopidogrel; P < 0.0001). Mean IPA was significantly lower with ticagrelor than clopidogrel between 48 and 168 h post-dose (P < 0.01). Similar findings were observed with the other assays. The average time for IPA to decline from 30% to 10% was 50.8 h with ticagrelor vs. 110.4 h with clopidogrel. CONCLUSIONS: In patients with HPI, recovery of platelet function was more rapid after discontinuation of ticagrelor than clopidogrel leading to significantly greater platelet reactivity by 48 h after the last dose in the ticagrelor group.


Assuntos
Adenosina/análogos & derivados , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Ticlopidina/análogos & derivados , Adenosina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Clopidogrel , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Plaquetária , Ticagrelor , Ticlopidina/administração & dosagem , Fatores de Tempo
13.
J Thromb Haemost ; 8(8): 1820-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20492465

RESUMO

BACKGROUND: The thienopyridine P2Y(12) receptor antagonist clopidogrel reduces the risk of arterial thrombosis and individual pharmacodynamic responses to clopidogrel are believed to reflect the levels of active metabolite (AM) generated. Rifampicin increases the inhibitory effect of clopidogrel on platelet aggregation (PA). We studied the response to clopidogrel before and during administration of rifampicin in order to study the relationship between individual AM levels and P2Y(12) blockade. METHODS: Healthy volunteers received a 600-mg loading dose of clopidogrel followed by 75 mg daily for 7 days and, after a washout period and treatment with rifampicin [300 mg twice a day (b.i.d.)], received the same regimen of clopidogrel. Clopidogrel AM levels were determined over 4 h after the clopidogrel loading dose and unblocked P2Y(12) receptor number was assessed using a (33) P-2MeSADP binding assay. PA was measured by optical aggregometry with ADP and TRAP. RESULTS: Rifampicin enhanced clopidogrel AM production [area-under-the-curve (AUC): clopidogrel 89±22 ng h mL(-1) , clopidogrel+rifampicin 335±86 ng h mL(-1) , P<0.0001], and P2Y(12) blockade (unblocked receptors: clopidogrel 48±24, clopidogrel+rifampicin 4±2, P<0.0001) and reduced PA (5 µmol L(-1) ADP: clopidogrel 20±4, clopidogrel+rifampicin 5±2, P<0.01). Increasing numbers of unblocked receptors were required for an aggregation response with a decreasing concentration of ADP. PA induced by ADP 2 µmol L(-1) was particularly sensitive to low levels of receptor blockade. CONCLUSION: Potentiation of clopidogrel AM production by rifampicin leads to greater P2Y(12) blockade and consequently greater inhibition of PA. PA responses to low concentrations of ADP are more sensitive to P2Y(12) blockade.


Assuntos
Sinergismo Farmacológico , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Receptores Purinérgicos P2Y12/química , Rifampina/administração & dosagem , Ticlopidina/análogos & derivados , Difosfato de Adenosina/química , Adulto , Área Sob a Curva , Plaquetas/efeitos dos fármacos , Clopidogrel , Doença da Artéria Coronariana/tratamento farmacológico , Esquema de Medicação , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária , Ticlopidina/administração & dosagem
14.
Int J Clin Pract ; 63(4): 667-70, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19335707

RESUMO

AZD6140, the first reversible oral P2Y(12) receptor antagonist, exhibits greater and more consistent inhibition of platelet aggregation than the irreversible thienopyridine clopidogrel. As a result of its reversible effect, AZD6140 may pose less risk for bleeding when antiplatelet treatment cannot be stopped at least 5 days before coronary artery bypass graft (CABG) surgery or other invasive procedures. The Dose conflrmation Study assessing anti-Platelet Effects of AZD6140 vs. clopidogRel in NSTEMI (DISPERSE2) trial showed overall comparable bleeding rates with antiplatelet treatment with AZD6140 90 mg twice daily or 180 mg twice daily vs. clopidogrel 75 mg once daily in 984 patients with non-ST-elevation acute coronary syndromes. A post hoc exploratory analysis of bleeding outcomes in the subset of 84 patients undergoing CABG in DISPERSE2 suggests reduced risk for total bleeding (41% and 58% vs. 62%), all major bleeding (38% and 50% vs. 62%), and life-threatening bleeding (22% and 38% vs. 54%) with AZD6140 90 mg (n = 32) and 180 mg (n = 26) vs. clopidogrel (n = 26) respectively. Trends suggested that major bleeding rates were reduced with AZD6140 (combined groups) vs. clopidogrel when treatment was stopped < or = 5 days prior to surgery (39% vs. 63%, p = 0.15) but not when treatment was stopped > 5 days before surgery (50% vs. 60%). This observation is consistent with the reversible binding of AZD6140 to the P2Y(12) receptor. Further prospective studies are planned to assess the relationship between this potential clinical benefit of AZD6140 and the reversibility of its antiplatelet effects.


Assuntos
Síndrome Coronariana Aguda/cirurgia , Adenosina/análogos & derivados , Hemorragia/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Síndrome Coronariana Aguda/complicações , Adenosina/efeitos adversos , Adenosina/uso terapêutico , Idoso , Ensaios Clínicos como Assunto , Clopidogrel , Ponte de Artéria Coronária , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Fatores de Risco , Ticagrelor , Ticlopidina/efeitos adversos , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento
15.
Circulation ; 119(1): 116-22, 2009 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-19103996

RESUMO

BACKGROUND: Platelets are believed to play an important role in atherogenesis and the vessel response to vascular injury. The P2Y(12) receptor (P2Y(12)) plays a central role in amplifying platelet aggregation, dense granule and alpha-granule secretion, P-selectin expression, microparticle formation, and procoagulant membrane changes, regardless of the activating stimulus. We hypothesized that P2Y(12) deficiency might reduce the vessel wall response to vascular injury as well as thrombosis in murine vascular injury models. METHODS AND RESULTS: P2Y(12)-deficient (-/-) mice and littermate controls (+/+) were bred on a C57 BL/6 background. In vivo murine models of arterial injury were employed alone and in combination with bone marrow transplantation to investigate the role of P2Y(12) in the vessel wall response to arterial injury and thrombosis. At 21 days after ferric chloride injury, neointima formation in P2Y(12)(-/-) arteries was significantly less than that observed in control strain arteries (P<0.025). In agreement with this, the intima-media ratio was significantly greater in femoral wire-injured arteries from P2Y(12)(+/+) compared with P2Y(12)(-/-) animals (P<0.05). Bone marrow transplantation was used to examine the importance of vessel wall P2Y(12) versus platelet P2Y(12). Analysis of arterial sections from chimeric animals at 21 days after injury revealed a smaller intima-media ratio in -/- to +/+ animals than in the positive (+/+ to +/+) control group (P<0.01). CONCLUSIONS: These data demonstrate a role for platelet P2Y(12) in the vessel wall response to arterial injury and thrombosis. This illustrates the manner in which platelets may contribute to atherogenesis and restenosis.


Assuntos
Plaquetas/fisiologia , Artéria Femoral/lesões , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2/metabolismo , Trombose/fisiopatologia , Animais , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Plaquetas/patologia , Transplante de Medula Óssea , Cloretos , Modelos Animais de Doenças , Feminino , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Compostos Férricos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Músculo Liso Vascular/patologia , Músculo Liso Vascular/fisiopatologia , Noxas/toxicidade , Selectina-P/metabolismo , Agregação Plaquetária/fisiologia , Receptores Purinérgicos P2Y12 , Trombose/patologia , Túnica Íntima/lesões , Túnica Íntima/patologia , Túnica Íntima/fisiopatologia
17.
Eur J Clin Microbiol Infect Dis ; 25(6): 382-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16767486

RESUMO

Pneumocystis jiroveci pneumonia is a common infection in patients with AIDS but an infrequent cause of pneumonia in cancer patients. Little is known about the impact of cancer type and hematopoietic stem cell transplantation on the presentation and outcome of P. jiroveci pneumonia in cancer patients. A retrospective cohort study of all patients with cancer and P. jiroveci pneumonia cared for at The M.D. Anderson Cancer Center during 1990-2003 was conducted. Eighty episodes of P. jiroveci pneumonia in 79 patients were identified. In most (67%) episodes, patients had a hematologic malignancy. In 23 (29%) episodes, patients had undergone hematopoietic stem cell transplantation. Twenty-seven percent of patients with histopathologically confirmed P. jiroveci pneumonia had nodular infiltrates on the radiographic study. Pleural effusion and pneumothorax were more common in patients with hematopoietic stem cell transplantation than in those with solid tumors. Clinical suspicion of P. jiroveci pneumonia was less common in patients with nodular infiltrates than in those without such a radiographic finding (7 vs. 39%; p=0.002). Twenty-six of 76 (34%) patients with data available died of P. jiroveci pneumonia. Predictors of death by univariate analysis included older age, tachypnea, high APACHE II score, use of mechanical ventilation or vasopressors, lower arterial pH level, absence of interstitial component, pneumothorax, and comorbid conditions (all p<0.05). Multivariate analysis identified the use of mechanical ventilation as an independent predictor of death. Death attributable to P. jiroveci pneumonia appeared to be higher in patients with hematopoietic stem cell transplantation. The clinical presentation of P. jiroveci pneumonia in cancer patients may be affected by the category of cancer and the history of hematopoietic stem cell transplantation. P. jiroveci pneumonia remains a rare yet severe infection in cancer patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias/complicações , Pneumocystis carinii , Pneumonia por Pneumocystis/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Anti-Infecciosos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Criança , Feminino , Neoplasias Hematológicas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/tratamento farmacológico , Pneumonia por Pneumocystis/microbiologia , Estudos Retrospectivos , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
18.
J Public Health Manag Pract ; 12(1): 97-102, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16340521

RESUMO

BACKGROUND: Hurricane Isabel had a massive negative environmental, public health, and economic impact; Virginia bore the highest death toll (32) among nine states affected by this storm. A descriptive mortality analysis was conducted to identify modifiable risk factors and corresponding injury prevention measures that might mitigate future natural disaster-related morbidity and mortality in Virginia. METHODS: Information for the decedents, including demographic data, health status, and injury circumstances, was collected from the records of the Virginia Office of the Chief Medical Examiner and Office of Vital Records/Health Statistics. Criteria from the National Hurricane Center were used to classify deaths as direct or indirect. Storm assessments and emergency-response reports were also reviewed. RESULTS: A total of 32 deaths associated with Hurricane Isabel occurred in several densely populated localities in southeastern and central Virginia. The median age of decedents was 48 years (range: 7-85 years). A disproportionately higher mortality (21 [66%] of 32) occurred among persons older than 45 years (Virginia 2000 Census data). Twelve deaths were directly caused by environmental factors related to the storm (eg, seven drowning deaths and five traumatic head injuries from falling trees). Twenty deaths were indirectly associated with the storm and its effects: six fatal motor vehicle crashes, five related to clean-up operations, seven associated with power outages, and two stress-related (ie, myocardial infarction and suicide). The presence of alcohol or drugs was observed in 9 (28%) of 32 deaths. CONCLUSIONS: Classifying deaths as direct or indirect facilitates better target interventions on the basis of the identification of modifiable risk factors underlying hurricane-associated fatal injuries. Public education messages that reinforce avoidance of use of alcohol and drugs during natural disaster situations might reduce risk for injury.


Assuntos
Desastres , Mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Virginia/epidemiologia
19.
Eur J Pharm Sci ; 27(1): 19-26, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16246535

RESUMO

Milling is a key process in the preparation of many solid dosage forms. One possible milling induced change is the production of small levels of disorder or amorphous material found predominantly at the surface of a powder, which could lead to significant chemical and physical instability. The influence of crystal habit on this change was investigated using beta-succinic acid, in plate like and needle like morphologies. beta-Succinic acid crystals with these habits were processed in a ball mill and a jet mill. SEM images indicated jet milled material was finer than the ball milled product. Powder X-ray diffraction of the milled powders revealed an amorphous halo at lower angles and peak broadening suggesting disorder though this could not be quantified accurately. In addition, a partial conversion during milling to the alpha form was noted. Quantitation of the alpha form in the milled powders indicated it was present at <2% (w/w). Plate and needle shaped particles had similar heats of solution pre-milling, however, all milled powders had lower heats of solution compared to the unmilled powers. The contribution of the alpha polymorph to the lower heats of solution was calculated to be insignificant. Therefore, the reduced heat of solution is attributed to a loss in crystallinity. The largest decreases were seen in the plate like morphology. These findings suggest that beta-succinic acid crystals with plate like morphology are more prone to crystallinity loss on milling compared to the needle like morphology. The mill type has also been shown to influence the final crystallinity.


Assuntos
Ácido Succínico/química , Tecnologia Farmacêutica , Varredura Diferencial de Calorimetria , Cristalização , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Pós , Propriedades de Superfície , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/métodos , Termodinâmica , Difração de Raios X
20.
Platelets ; 16(6): 340-5, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16194864

RESUMO

Genetic variations of the protease-activated receptor-1 (PAR-1) have been associated with platelet receptor density and linked to thrombin receptor-activating peptide (TRAP)-induced phenotypes of platelet aggregation and P-selectin expression. We investigated whether the PAR-1 intervening sequence-14 A>T dimorphism influences platelet procoagulant activity. We also determined whether the P2Y12 antagonist clopidogrel could offset any observed functional polymorphism of the PAR-1 receptor by inhibiting P2Y12-mediated amplification of TRAP-induced responses. We studied 54 patients listed for elective percutaneous coronary intervention assessing TRAP-induced platelet aggregation and markers of procoagulant activity. Platelet responses were measured at baseline, 4 h post clopidogrel 300 mg, and 10 and 28 days following clopidogrel 75 mg daily. Each patient was genotyped for the PAR-1 intervening sequence-14 A/T dimorphism. Increased platelet aggregation and procoagulant responses were observed with PAR-1 A allele homozygotes. Clopidogrel significantly inhibited these platelet responses regardless of PAR-1 genotype, but did not offset the hyper-reactivity associated with the A/A homozygotes. We conclude that a common sequence variation within the PAR-1 gene influences TRAP-induced platelet procoagulant activity as well as aggregation. Higher platelet reactivity associated with PAR-1 IVSn-14 A allele homozygotes persists despite clopidogrel therapy. These individuals may be at higher risk of thromboembolic events and may require additional anti-platelet medication.


Assuntos
Fatores de Coagulação Sanguínea/efeitos dos fármacos , Doença das Coronárias/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Receptor PAR-1/genética , Receptor PAR-1/metabolismo , Ticlopidina/análogos & derivados , Alelos , Fatores de Coagulação Sanguínea/metabolismo , Clopidogrel , Doença das Coronárias/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Variação Genética , Genótipo , Homozigoto , Humanos , Masculino , Proteínas de Membrana/antagonistas & inibidores , Pessoa de Meia-Idade , Fenótipo , Antagonistas do Receptor Purinérgico P2 , Receptor PAR-1/efeitos dos fármacos , Receptores Purinérgicos P2Y12 , Receptores de Trombina/metabolismo , Ticlopidina/administração & dosagem , Ticlopidina/uso terapêutico
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