247 resultados para Haematology


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Platelet-derived microparticles that are produced during platelet activation are capable of adhesion and aggregation. Endothelial trauma that occurs during percutaneous transluminal coronary angioplasty (PTCA) may support platelet-derived microparticle adhesion and contribute to development of restenosis. We have previously reported an increase in platelet-derived microparticles in peripheral arterial blood with angioplasty. This finding raised concerns regarding the role of platelet-derived microparticles in restenosis, and therefore the aim of this study was to monitor levels in the coronary circulation. The study population consisted of 19 angioplasty patients. Paired coronary artery and sinus samples were obtained following heparinization, following contrast administration, and subsequent to all vessel manipulation. Platelet-derived microparticles were identified with an anti-CD61 (glycoprotein IIIa) fluorescence-conjugated antibody using flow cytometry. There was a significant decrease in arterial platelet-derived microparticles from heparinization to contrast administration (P=0.001), followed by a significant increase to the end of angioplasty (P=0.004). However, there was no significant change throughout the venous samples. These results indicate that the higher level of platelet-derived microparticles after angioplasty in arterial blood remained in the coronary circulation. Interestingly, levels of thrombin-antithrombin complexes did not rise during PTCA. This may have implications for the development of coronary restenosis post-PTCA, although this remains to be determined.

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Clinical evaluation of arterial potency in acute ST-elevation myocardial infarction (STEMI) is unreliable. We sought to identify infarction and predict infarct-related artery potency measured by the Thrombolysis In Myocardial Infarction (TIMI) score with qualitative and quantitative intravenous myocardial contrast echocardiography (MCE). Thirty-four patients with suspected STEMI underwent MCE before emergency angiography and planned angioplasty. MCE was performed with harmonic imaging and variable triggering intervals during intravenous administration of Optison. Myocardial perfusion was quantified offline, fitting an exponential function to contrast intensity at various pulsing intervals. Plateau myocardial contrast intensity (A), rate of rise (beta), and myocardial flow (Q = A x beta) were assessed in 6 segments. Qualitative assessment of perfusion defects was sensitive for the diagnosis of infarction (sensitivity 93%) and did not differ between anterior and inferior infarctions. However, qualitative assessment had only moderate specificity (50%), and perfusion defects were unrelated to TIMI flow. In patients with STEMI, quantitatively derived myocardial blood flow Q (A x beta) was significantly lower in territories subtended by an artery with impaired (TIMI 0 to 2) flow than those territories supplied by a reperfused artery with TIMI 3 flow (10.2 +/- 9.1 vs 44.3 +/- 50.4, p = 0.03). Quantitative flow was also lower in segments with impaired flow in the subtending artery compared with normal patients with TIMI 3 flow (42.8 +/- 36.6, p = 0.006) and all segments with TIMI 3 flow (35.3 +/- 32.9, p = 0.018). An receiver-operator characteristic curve derived cut-off Q value of

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Background: Treatment with interferon and subcutaneous cytarabine produces superior cytogenetic responses in chronic myeloid leukaemia (CML) than treatment with interferon alone, but at the expense of greater toxicity. Cytarabine ocfosfate (YNK01) is an oral precursor of cytarabine that may overcome some of the inconvenience and toxicities associated with subcutaneous cytarabine administration. Patients and methods: We studied the efficacy and tolerability of combination therapy with interferon-alpha-2b and YNK01 in patients with newly diagnosed, untreated CML. Forty patients were treated with interferon-alpha-2b (5 MU/m(2)/day) plus monthly courses of YNK01 (600 mg/day for 10 days) for I year. Results: The 6-month complete haematological response rate was 63% and the 1-year major cytogenetic response rate was 30%, with 10% of cytogenetic responses being complete. With a median follow-up of 57 months, the estimated 5-year overall survival was 86% (95% confidence interval 70% to 94%). Treatment tolerability was poor, with toxicity leading to discontinuation of one or both drugs in 60% of cases. The median daily dose of interferon alpha-2b was 7.75 MU and the median dose of YNK01 was 600 mg/day for each 10-day treatment cycle. Conclusions: Interferon-alpha-2b and YNK01 produce cytogenetic responses comparable to those achieved with interferon-alpha-2b and parenteral cytarabine, although toxicity was excessive. Alternate dosing strategies may enhance the tolerability of YNK01.

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Intensive therapy and autologous blood and marrow transplantation (ABMT) is an established post-remission treatment for acute myeloid leukemia (AML), although its exact role remains controversial and few data are available regarding longer-term outcomes. We examined the long-term outcome of patients with AML transplanted at a single center using uniform intensive therapy consisting of etoposide, melphalan and TBI. In all, 145 patients with AML underwent ABMT: 117 in first remission, 21 in second remission and seven beyond second remission. EFS and OS were significantly predicted by remission status (P

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An entire female English bull terrier, aged five years and one month, was diagnosed with polycystic kidney disease by renal ultrasonography. It had thickening and abnormal motion of the mitral valve on 2D and M mode echocardiography, and left ventricular outflow tract obstruction, characterised by turbulence in the left ventricular outflow tract and elevated aortic blood flow velocity, detected by colour flow and spectral Doppler echocardiography, respectively. Two years later, haematology, serum biochemistry and urinalysis data suggested the presence of compensated renal failure. The dog was euthanased at 10 years and eight months of age, with haematology, serum biochemistry and urinalysis data indicating decompensated chronic renal failure. Postmortem examination confirmed polycystic kidney disease, chronic renal disease, mitral and aortic valvular myxomatous degeneration, and mixed mammary neoplasia. This case demonstrates that bull terriers with polycystic kidney disease may develop associated chronic renal failure.

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Recognition that primary aldosteronism (PAL) is a common specifically treatable form of hypertension and that most patients are normokalemic has led to a marked increase in demand for aldosterone/renin ratio (ARR) testing as a means of screening for this disorder. The value of this screening test depends on an appreciation of many factors (such as diet, posture, time of day, presence of hypokalemia, medications, age, and renal function), which can affect the results, on the care with which these factors are either controlled or their effects taken into account, and on access to reliable and reproducible assays for renin and aldosterone. Even then, physiological day-to-day variability reduces the value of a single estimation, and repeated testing is necessary before a decision that PAL is highly likely (warranting further testing) or highly unlikely can be made. Provided that testing of aldosterone suppressibility is always carried out to confirm or exclude the diagnosis, and the subtype is determined by hybrid gene testing and adrenal venous sampling, wide application of the ARR can have a major beneficial clinical impact with improved therapeutic outcomes, including possible cure in those with unilateral disease.

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A 12-year-old male castrated Samoyed dog was presented with left-sided epistaxis and sneezing. Diagnostic procedures included haematology and biochemistry testing, thoracic radiography, fine needle aspiration of regional lymph nodes, CT, rhinoscopy, incisional biopsy and histopathology. Squamous cell carcinoma of the rostral nasal cavity was diagnosed, with no evidence of metastatic disease. External beam radiation was not an accessible treatment option. Complete surgical resection of the tumour would have required a larger, more disfiguring resection of nasal planum and maxilla than the owner was prepared to accept and may have been associated with an unacceptable morbidity. As an alternative, the extent of disease was reduced using a combination of carboplatin, doxorubicin and piroxicam chemotherapy. This allowed a less extensive nasal planum removal to be performed to remove residual disease with clean margins. The patient achieved a 14 month disease free interval from the time of surgery to the time of local recurrence. Survival time from diagnosis to eventual euthanasia for progressive local disease was 18 months.

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An increase in left ventricular mass (LVM) occurs in the presence of type 2 diabetes, apparently independent of hypertension (1), but the determinants of this process are unknown. Brachial blood pressure is not representative of that at the ascending aorta (2) because the pressure wave is amplified from central to peripheral arteries. Central blood pressure is probably more clinically important since local pulsatile pressure determines adverse arterial and myocardial remodeling (3,4). Thus, an inaccurate assessment of the contribution of arterial blood pressure to LVM may occur if only brachial blood pressure is taken into consideration. In this study we sought the contribution of central blood pressure (and other interactive factors known to affect wave reflection, e.g., glycemic control and total arterial compliance) to LVM in patients with type 2 diabetes.

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The characterization of blood pressure in treatment trials assessing the benefits of blood pressure lowering regimens is a critical factor for the appropriate interpretation of study results. With numerous operators involved in the measurement of blood pressure in many thousands of patients being screened for entry into clinical trials, it is essential that operators follow pre-defined measurement protocols involving multiple measurements and standardized techniques. Blood pressure measurement protocols have been developed by international societies and emphasize the importance of appropriate choice of cuff size, identification of Korotkoff sounds, and digit preference. Training of operators and auditing of blood pressure measurement may assist in reducing the operator-related errors in measurement. This paper describes the quality control activities adopted for the screening stage of the 2nd Australian National Blood Pressure Study (ANBP2). ANBP2 is cardiovascular outcome trial of the treatment of hypertension in the elderly that was conducted entirely in general practices in Australia. A total of 54 288 subjects were screened; 3688 previously untreated subjects were identified as having blood pressure >140/90 mmHg at the initial screening visit, 898 (24%) were not eligible for study entry after two further visits due to the elevated reading not being sustained. For both systolic and diastolic blood pressure recording, observed digit preference fell within 7 percentage points of the expected frequency. Protocol adherence, in terms of the required minimum blood pressure difference between the last two successive recordings, was 99.8%. These data suggest that adherence to blood pressure recording protocols and elimination of digit preferences can be achieved through appropriate training programs and quality control activities in large multi-centre community-based trials in general practice. Repeated blood pressure measurement prior to initial diagnosis and study entry is essential to appropriately characterize hypertension in these elderly patients.