Twelve carriers of thalassaemia intermedia were studied. Their clinical and haematological picture was distinctly different from that in both heterozygotes and homozygotes for beta thalassaemia. Several genetic patterns were found responsible for thalassaemia intermedia: beta/delta beta thalassaemia, alpha 2 beta/beta thalassaemia-heterocellular HPFH. In a few subjects the genetic picture indicated that the patients were homozygous for beta thalassaemia, in spite of the mildness of the clinical situation. The lack of genetic uniformity was refelcted in very wide Hb A2 (2.5--8.7%) and Hb F (7.5--96.9%) ranges, as opposed to the noticeable degree of biochemical uniformity indicated by the very similar imbalance of globin chain synthesis: 0.33-0.54 for the non-alpha/alpha chain ratio in the peripheral blood. The mean for this parameter (0.43 +/- 0.05) was significantly different (P less than 0.001) from that observed in heterozygous carriers (0.60 +/- 0.10) and homozygous carriers (0.11 +/- 0.05) for beta thalassaemia. The marrow blood displayed a comparable pattern. It is therefore suggested that the severity of thalassaemia is attributable to the degree of chain synthesis imbalance.
We periodically analyzed bone-marrow cytogenetic features in 8 patients belonging to a series of 38 subjects with polycythemia vera (PV), all treated with recombinant interferon-alpha 2a (rIFN-alpha) at a weekly dose of 9,000,000 IU. Six out of these 8 patients never showed any chromosome alterations, while 2 displayed at diagnosis the presence of trisomy 8 in all bone-marrow metaphases. Interestingly enough, in these 2 patients rIFN-alpha treatment was able to induce not only complete hematological response but also the disappearance of trisomy 8, as shown by conventional cytogenetic investigation and fluorescence in situ hybridization performed on bone-marrow cells after 1 year of treatment. This finding indicates that, as previously shown in chronic myeloid leukemia, in PV rIFN-alpha can also eradicate the malignant clone by means of a selective effect on bone-marrow transformed cells. Am.
Summary. The prevalence of gastroduodenal lesions is higher in polycythaemia vera (PV) than in the general population. However, the role of Helicobacter pylori (H. pylori) in the pathogenesis of such lesions is unknown. The aim of our study was to evaluate the prevalence of gastroduodenal lesions in PV patients and dyspeptic controls, and to assess the role of PV and H. pylori infection in inducing them. Thirty-five PV patients fulfilling selection criteria and 73 age-and sex-matched controls underwent upper gastrointestinal endoscopy. Six gastric mucosal biopsies were taken in all patients and controls, and analysed for presence of H. pylori; serum anti-CagA was assayed by Western blot. Data were analysed with descriptive statistics and multivariate regression analysis. Compared with controls, PV patients showed a significantly higher frequency of erosions (46% versus 12%), ulcers (29% versus 7%), H. pylori positivity (83% versus 57%), and anti-CagA positivity (66% versus 37%). Fourteen out of 20 (70%) asymptomatic PV patients had gastroduodenal lesions. At multivariate analysis, H. pylori, presence of PV alone, and both PV and anti-CagA were significantly and strongly associated with a higher frequency of gastroduodenal lesions (P < 0AE05, P < 0AE01 and P < 0AE05 respectively). Both PV and H. pylori infection were independent risk factors for gastroduodenal lesions; the underlying pathogenetic mechanism responsible for gastroduodenal lesions in PV possibly involves blood mucosal flow and trophism. The higher susceptibility of H. pylori infection and the high frequency of asymptomatic gastroduodenal lesions in PV patients suggest a surveillance of these patients.
Abstract-Limited information is available for humans on whether blood viscosity affects total peripheral resistance and, hence, blood pressure. Our study was aimed at assessing the effects of acute changes in blood viscosity on both clinic and 24-hour ambulatory blood pressure (BP) values. In 22 normotensive and hypertensive patients with polycythemia, clinic and 24-hour ambulatory BPs were measured before and 7 to 10 days after isovolumic hemodilution; this was performed through the withdrawal of 400 to 700 mL of blood, with concomitant infusion of an equivalent volume of saline-albumin solution. Hematocrit, plasma renin activity, plasma endothelin-1, right atrial diameter (echocardiography), and blood viscosity were measured under both conditions. Plasma renin activity and right atrial diameter were used as indirect markers of blood volume changes. Plasma endothelin-1 was used to obtain information on a vasomotor substance possibly stimulated by our intervention, which could counteract vasomotor effects. Isovolumic hemodilution reduced hematocrit from 0.53Ϯ0.05 to 0.49Ϯ0.05 (PϽ.01). Plasma renin activity, plasma endothelin-1 and right atrial diameter were unchanged. Clinic blood pressure was reduced by hemodilution (systolic, 144.3Ϯ5.4 to 136.0Ϯ3.9 mm Hg[meanϮSEM]; diastolic, 87.0Ϯ2.8 to 82.1Ϯ2.6 mm Hg, PϽ.05 for both) and a reduction was observed also for 24-hour average ABP (systolic, 133.6Ϯ2.9 to 129.5Ϯ2.7 mm Hg; diastolic, 80.0Ϯ2.0 to 77.3Ϯ1.7 mm Hg, PϽ.05 for both). The reduction was consistent in hypertensive patients (nϭ12), whereas in normotensive patients (nϭ10) it was small and not significant. Both clinic and 24-hour average heart rates were unaffected by the hemodilution. Thus, in polycythemia, reduction in blood viscosity without changing blood volume causes a significant fall in both clinic and 24-hour ambulatory BPs; this is particularly true when, as can often happen, blood pressure is elevated. This emphasizes the importance this variable may have in the determination of blood pressure and the potential therapeutic value of its correction when altered. (Hypertension. 1998;31:848-853.)Key Words: blood viscosity Ⅲ hemodilution Ⅲ blood pressure monitoring, ambulatory Ⅲ hemorheology B P is determined by cardiac output and peripheral vascular resistance. The latter depends to a large degree on the caliber and length of arterioles. It also depends, however, on blood viscosity, with which it bears a linear relationship over a wide range of values. 1Although studied extensively in animals, 2-5 the effects of blood viscosity on human BP have received only limited attention except for (1) the epidemiological evidence that there is a relationship between hematocrit and BP levels in both normotensive and hypertensive subjects 6 -15 and (2) the clinical evidence of an increased prevalence of hypertension in subjects with secondary eritrocytosis and polycythemia. 16,17 In particular, no information is available on the BP effects of interventions that reduce blood viscosity (ie, whether this maneuver induces...
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