Incidence of aspirin resistance is higher in patients with acute coronary syndrome and atrial fibrillation than without atrial fibrillation

SUMMARY In patients with atrial fibrillation, standard anticoagulation with a vitamin K antagonist plus dual antiplatelet therapy with a P2Y12 inhibitor and aspirin is the standard of care after percutaneous coronary intervention (PCI). While this therapy reduces the risk of thrombosis and stroke, it increases the risk of bleeding. It is unclear whether the antiplatelet effect of aspirin and clopidogrel may worsen atrial fibrillation (AF). OBJECTIVE Thus we aimed to analyze platelet aspirin resistance (AR) and clopidogrel resistance (CR) in acute coronary (ACS) patients based on sinus rhythm (SR) and AF. METHODS In this prospective trial, we included 543 patients (mean age: 62± 12 years; range: 26 - 89 years) who were on aspirin and clopidogrel therapy after the diagnosis of acute coronary syndrome. AR and CR were analyzed by a Multiplate® MP-0120 device by using the method of whole blood aggregometry. RESULTS AF patients had significantly higher age, mean platelet volume, and High-Sensitivity C-Reactive Protein (p< 0.01 for each parameter). Similarly, Arachidonic-acid induced (ASPI) aggregation was higher in AF patients compared to SR patients (666±218 vs. 187±179, p<0.001). Among the ACS patients, significantly more female patients had AF (p<0.001). The incidence of hypertension in the AF group was higher compared to the SR group (p<0.001). However, adenosine diphosphate levels were not at a significant level in the two groups. CONCLUSION Our findings indicate that the platelet inhibitory effect of Aspirin was worse for patients with AF, suggesting that the effectiveness of aspirin may be less in the prophylaxis of thromboembolism and more a bleeding risk.

RESUMO Em pacientes com fibrilação atrial, a anticoagulação padrão com antagonista da vitamina K mais terapia antiplaquetária dupla (DAPT) com inibidor de P2Y12 e aspirina é o padrão de tratamento após intervenção coronária percutânea (ICP). Enquanto essa terapia reduz o risco de trombose e derrame, aumenta o risco de sangramento. Não está claro se o efeito antiplaquetário da aspirina e do clopidogrel pode piorar a fibrilação atrial (FA). OBJETIVO Analisar a resistência à aspirina plaquetária (AR) e ao clopidogrel (CR) em pacientes coronarianos agudos (SCA) com base no ritmo sinusal (SR) e na FA. MÉTODOS Neste estudo prospectivo, foram incluídos 543 pacientes (idade média: 62±12 anos; intervalo: 26-89 anos) em uso de aspirina e clopidogrel após o diagnóstico de síndrome coronariana aguda. AR e CR foram analisados por um dispositivo Multiplate® MP-0120, utilizando o método de agregometria de sangue total. RESULTADOS Os pacientes com FA apresentaram valores significativamente maiores para idade, volume médio de plaquetas e proteína C reativa de alta sensibilidade (p<0,01 para cada parâmetro). Da mesma forma, a agregação induzida por ácido araquidônico (Aspi) foi maior nos pacientes com FA em comparação com os pacientes com SR (666±218 vs. 187±179, p<0,001). Entre os pacientes com SCA, significativamente mais pacientes do sexo feminino apresentaram FA (p<0,001). A incidência de hipertensão no grupo FA foi maior em comparação com o grupo SR (p<0,001). No entanto, os níveis de difosfato de adenosina não foram expressivamente significativos nos dois grupos. CONCLUSÃO Nossos achados indicam que o efeito inibitório plaquetário da aspirina foi pior em pacientes com FA, sugerindo que a eficácia da aspirina pode ser menor na profilaxia do tromboembolismo, com maior risco de sangramento.

Pacientes que no responden a prueba con inhibidores de la bomba de protones: diagnóstico y manejo / Patients with symptoms refractory to proton pump inhibitors: diagnosis and management

One third of patients with symptoms of gastro-esophageal reflux disease (GERD) are unresponsive to proton-pump inhibitors (PPIs). Most of them suffer from functional heartburn or other functional pathology. The mechanisms involved include non-acid reflux, aerophagia and belching, reflux hypersensitivity and psychological comorbidities. After ensuring adherence to nonpharmacologic measures and changes in types of PPIs, the initial diagnostic strategy is based on finding erosive esophagitis and rule out eosinophilic esophagitis in endoscopy and prove or rule out abnormal gastro esophageal reflux (GER) and association of symptoms by pH monitoring with or without impedanciometry. After ruling out GERD, the association of symptoms in these tests can direct therapy toward the use of baclofen or pain modulators.

Un tercio de los pacientes con síntomas de enfermedad por reflujo gastro-esofágico (ERGE) no responden a inhibidores de la bomba de protones (IBP). La mayoría de ellos padece una patología esofágica funcional. Los mecanismos implicados incluyen reflujo no ácido, aerofagia y eructos, hipersensibilidad al ácido y comorbilidad psicológica. Luego de asegurar adherencia a medidas no farmacológicas y cambios en tipos de IBP, la estrategia diagnóstica inicial se basa en hallazgo de esofagitis erosiva y descarte de esofagitis eosinofílica en la endoscopia, así como objetivar/descartar RGE patológico y asociación de síntomas mediante pHmetría con o sin impedanciometría. Tras descartar RGE patológico, la asociación de síntomas en estas últimas pruebas pueden dirigir la terapia hacia el uso de baclofeno y moduladores del dolor.

Características fenotípicas da hipertensão arterial resistente na população brasileira / Phenotypic characteristics of resistant hypertension in the Brazilian population

Hipertensão resistente (HAR) é definida como a pressão arterial que permanece acima da meta pressórica, apesar do uso de três classes de anti-hipertensivos em doses otimizadas, sendo um deles um diurético. Além disso, são considerados também hipertensos resistentes os pacientes que usam quatro ou mais classes e possuem suas pressões controladas. Embora essa definição seja útil na categorização de um maior grupo de resistentes, visto esses dois subgrupos compartilharem alto risco cardiovascular, algumas importantes particularidades clínicas e fisiopatológicas necessitam ser mais bem avaliadas antes de resistentes controlados e não controlados pertencerem ao mesmo grupo. Foram comparadas algumas características cardiovasculares nesses dois subgrupos de hipertensos resistentes. Embora algumas semelhanças, o subgrupo HRNC apresenta fenótipos cardiovasculares com pior prognóstico como maior rigidez vascular e hipertrofia ventricular esquerda, além de função endotelial mais prejudicada e menor queda de pressão arterial no período noturno, entre outras. Frente às diferenças, o subgrupo HRNC está associado à maior risco cardiovascular, podendo ser considerado mais resistente ao tratamento anti-hipertensivo. Além da importância de melhor prevenção e tratamento da HAR com medidas de identificar precocemente os fatores de risco e otimizar a terapia farmacológica, algumas implicações clínicas devem ser consideradas na abordagem de pacientes controlados e não controlados como semelhantes ao grupo de resistentes.

Resistant hypertension (RH) is defined as blood pressure that remains above target in spite of the concurrent use of three or more classes of antihypertensive drugs at optimized doses (UCRH), with one of them being a diuretic. Moreover, patients whose blood pressure is controlled while using four or more antihypertensive medications are also considered controlled resistant hypertensive (CRH) subjects. Although this definition may be useful in terms of categorizing a larger group of resistant hypertensive individuals, as these two subgroups share high cardiovascular risk, some important clinical and pathophysiologic particularities need to be better evaluated, before considering resistant controlled and uncontrolled patients as part of the same group. We compared cardiovascular characteristics of these two subgroups with resistant hypertension. In spite of some similar features, the UCRH subgroup has cardiovascular phenotypes with worse prognosis, such as increased vascular stiffness and left ventricular hypertrophy, as well as more impaired endothelial function and lower nocturnal blood pressure dipping, among others. Considering these differences, the UCRH subgroup is associated with greater cardiovascular risk and may be considered as more resistant to antihypertensive treatment. In addition to the importance of better prevention and treatment of resistant hypertension by identifying early risk factors and optimizing drug therapy, some clinical implications must be considered when managing controlled and uncontrolled patients as similar to the resistant hypertension group.

Simultaneous evaluation of in vivo glucocorticoid sensitivity and expression of glucocorticoid receptor alpha-isoform in rheumatoid arthritis patients / Avaliação concomitante da sensibilidade in vivo aos glicocorticóides e da expressão da isoforma alfa do receptor de glicocorticóide em pacientes com artrite reumatóide

OBJECTIVES: To analyze glucocorticoid (GC) sensitivity using intravenous very low dose dexamethasone suppression test (IV-VLD-DST) in patients with rheumatoid arthritis (RA) and its correlation with glucocorticoid receptor alpha-isoform (GRα) gene expression. METHODS: We evaluated 20 healthy controls and 32 RA patients with Health Assessment Questionnaire (HAQ) and Disease Activity Score 28 joints (DAS) scores and IV-VLD-DST and GRα expression in mononuclear cells. RESULTS: Basal cortisol and the percentage of cortisol reduction after IV-VLD-DST were lower in RA patients than in controls, whereas GRα expression was similar among groups. In the RA group there was an inverse correlation between GRα expression and the percentage of cortisol suppression that was not observed in controls. There was a direct relationship between DAS and GRα expression. CONCLUSIONS: Mechanisms involved in GC resistance observed in patients with RA are possibly not at the level of GRα gene expression, since it was similar among groups and GRα increased with disease activity.

OBJETIVOS: Determinar a sensibilidade aos glicocorticóides (GC) utilizando teste de supressão com dexametasona em doses muito baixas (IV-VLD-DST) em pacientes com artrite reumatóide (AR) e sua correlação com a expressão gênica da isoforma alfa do receptor glicocorticóide (GRα). MÉTODOS: Foram avaliados 20 controles saudáveis e 32 pacientes com AR com Health Assessment Questionnaire (HAQ) e Disease Activity Score 28 joints (DAS), IV-VLD-DST e expressão do GRα em células mononucleares. RESULTADOS: Cortisol basal e porcentagem de redução do cortisol após IV-VLD-DST foram menores no grupo AR do que nos controles, enquanto a expressão de GRα foi similar entre eles. No grupo com AR, ocorreu correlação negativa entre a expressão do GRα e a porcentagem de supressão do cortisol, enquanto nos controles não houve correlação. Ocorreu relação direta entre DAS e expressão de GRα . CONCLUSÕES: Sugerimos que os mecanismos envolvidos na resistência aos GC observada na AR não estejam ao nível da expressão gênica do GRα, já que esta é igual entre os grupos e aumenta com a gravidade da doença.

Shigellosis : challenges & management issues.

Infectious diseases kill about 11 million children each year while acute diarrhoeal diseases account for 3.1 million deaths in children under 5 yr of age, of which 6,00,000 deaths annually are contributed by shigellosis alone. Shigellosis, also known as acute bacillary dysentery, is characterized by the passage of loose stools mixed with blood and mucus and accompanied by fever, abdominal cramps and tenesmus. It may be associated with a number of complications of which haemolytic uraemic syndrome is the most serious. Shigellosis is caused by Shigella spp. which can be subdivided into four serogroups namely S.sonnei, S.boydii, S.flexneri and S.dysenteriae. Organisms as low as 10-100 in number can cause the disease. Shigellosis can occur in sporadic, epidemic and pandemic forms. Epidemics have been reported from Central American countries, Bangladesh, Sri Lanka, Maldives, Nepal, Bhutan, Myanmar and from the Indian subcontinent, Vellore, eastern India and Andaman and Nicobar islands. Plasmid profile of shigellae in Kolkata has shown a correlation between presence of smaller plasmids and shigellae serotypes- indicating epidemiological changes of the species. Diagnosis of shigellosis is essentially clinical. Laboratory diagnosis includes stool culture and polymerase chain reaction (PCR). Treatment includes use of an effective antibiotic, rehydration therapy (if there is dehydration) and appropriate feeding during and after an episode of shigellosis. Hand-washing is the single most important strategy for prevention of transmission of shigellosis from person to person. A safe and effective vaccine should be developed against the more important circulating strains i.e., S. dysenteriae type 1 and S. flexneri 2a.

Epidemiological, clinical & pharmacological study of antimony-resistant visceral leishmaniasis in Bihar, India.

BACKGROUND & OBJECTIVES: Sodium antimony gluconate (SAG) is reported to be losing its efficacy in Bihar as a first line drug for treatment of visceral leishmaniasis (VL). Concerned with the increasing incidence of antimony-resistant VL patients in Bihar, we undertook an epidemiological, clinical and pharmacological study to formulate a scientific basis for choosing a suitable first line drug for VL. METHODS: Consecutive, fresh and parasitologically confirmed patients of VL from different geographical areas of Bihar were considered for inclusion in the study. Parasites isolated from patients were tested in vitro to assess their response to sodium antimony gluconate (SAG) to 20 microg/ml, response to 20 mg/kg of SAG for 5 days in experimentally induced VL in BALB/c mice from those isolates, and response to SAG in patients treated with SAG for 28 days. Similarly response in culture (1 microg/ml) to amphotericin B (AMB) of all 282 isolates, (1 mg/kg body wt for 20 days) in patients and infected BALB/c mice (1 mg/kg body wt for 5 days) was determined. Antimony levels of plasma were determined at 2, 8 and 24 h after intramuscular injection of SAG. Patients unwilling for SAG treatment or relapsed after SAG treatment and withdrawn from SAG group because of toxicity were treated with AMB. Plasma antimony levels were estimated by atomic absorption spectrometer. RESULTS: Though antimony sensitive and resistant patient were distributed in all 14 districts of Bihar studied, there was a significant variation from district to district. Of the 123 patients included in the SAG treatment group, 19 were withdrawn due to development of toxicity and 2 died; 178 patients were treated with AMB. No patient in AMB group developed any toxicity or died. Only 47 (46%) of 102 patients, 106 (37.6%) of 282 infected macrophages, 90 (52.9%) of 170 experimental infections were cured with SAG. Mc Nemar's test on paired comparisons showed statistical significance difference (P<0.01) between infected macrophage and experimental infection. AMB cured all patients, infected mice and cleared parasites from all isolates. INTERPRETATION & CONCLUSION: Antimony resistant strains of L. donovani were wide spread over different geographical areas in Bihar. SAG cured lesser percentage of VL cases clinically compared to AMB and should be replaced by AMB as a first line drug.

Cabergolina como alternativa no tratamento clínico de prolactinonas: experiência na intolerância/resistência à bromocriptina / Cabergoline as an alternative in prolactinomas clinical treatment: experience in the bromocriptine intolerance/resistance

Cabergolina (CAB, Pharmacia) é um agonista dopaminérgico derivado do ergot com longa ação após administração oral, que já tem demonstrado ser de utilidade para o tratamento da hiperprolactinemia. Quarenta e cinco pacientes (36 mulheres, 9 homens) com prolactinomas (27 micro, 18 macro), intolerantes e/ou resistentes à bromocriptina (BRC) foram tratados com dose semanal de CAB de 0,25 a 7mg (mediana: 1mg) dividida de 1 a 7 administrações. O tratamento, em compassionate basis, variou de 1 a 38 meses (mediana: 12 meses). Entre os 38 pacientes com intolerância persistente à BRC (sintomas digestivos, n=27; hipotensão postural, n=13; congestão nasal, n=5; manifestações psiquiátricas, n=4; retenção urinária, n=1), somente 5 permaneceram intolerantes à CAB (sintomas digestivos, n=2; hipotensão postural, n=2; congestão nasal, n=1). Todos aqueles que toleraram bem a BRC também o fizeram com CAB. Onze casos alcançaram normalização da prolactina durante o uso de BRC. Estes pacientes e outros 19 também resolveram a hiperprolactinemia com CAB. Entretanto, somente 3 dos 7 pacientes resistentes (dose diária de BRC de 10 a 25mg) tiveram a prolactina sérica normalizada durante o uso de CAB. Redução tumoral foi documentada por ressonância mag-nética ou tomografia computadorizada em 7 macroprolactinomas durante o tratamento com CAB. Assim, devido à sua excelente eficácia, tolerabilidade e comodidade posológica, a CAB apresenta-se como importante alternativa no tratamento clínico dos prolactinomas.

Antibiotic resistance--a close look.

The discovery of antibiotic greatly improved the human health care system. But today we are facing the problem of antibiotic resistance due to uncontrolled use of the compound. This can be by passed by controlled use of antibiotic and formulation of newer ones.

Asma corticóideo resistente / Corticosteriod resistance in asthma

Desde hace años, los clínicos se han encontrado con pacientes asmáticos que no responden a corticoides. Estos comprenden pacientes con obstrucción irreversible de su vía aérea, pacientes con enfermedad severa que requieren altas dosis y un subgrupo menos frecuente, que se caracteriza por obstrucción bronquial reversible con ß2 agonistas, pero que no responden a corticoides, a dosis adecuadas. Diversos autores estudiaron la farmacocinética de los corticoides en estos pacientes, así como la presencia de anticuerpos antilipocortina, y los receptores esteróideos, no pudiendo aclarar el mecanismo de esta resistencia. La explicación a este fenómeno parece centrarse en la respuesta de los linfocitos, monocitos y eosinófilos de los pacientes a estas drogas, con disminución de efecto sobre varias funciones de las mismas, que nos acerca a la comprensión de la inflamación bronquial en asma

Unique bioactivation of tiazofurin--studies with resistant cells.

Using resistant cells mechanism of action of new oncolytic nucleoside, tiazofurin (2-beta-D-ribofuranosyl thiazole-4 carboxamide, RTC) was studied in tissue cultured cells of Chinese Hamster Ovary cells (CHO-cells). Tiazofurin got converted in CHO-cells to tiazofurin-monophosphate and to NAD-analogue, a potent inhibitor of inosinate dehydrogenase. Resistant cells produced tiazofurin-5'-monophosphate in vitro but had a much reduced capacity to produce NAD-analogue, indicating absence of any effect of tiazofurin on incorporation of [14C]formate into guanine, inhibition of inosinate dehydrogenase as well as GTP levels in resistant cells. Using competition with various possible substrates it is found that the initial tiazofurin metabolism is catalysed by nicotinamide nucleoside kinase and NAD-analog formation is mediated by NAD-pyrophosphorylase. Decreased activity of the latter enzyme found in tiazofurin resistant cells not only inhibited the NAD analog formation from tiazofurin-5'-monophosphate but also the NAD-formation from nictotinamide-5'-monophosphate.