Diagnostic and therapeutic problems in 10 cases of pheochromocytomae.

Ten cases of pheochromocytomae, of which eight were benign and two malignant have been considered. All patients presented with hypertension, either paroxysmal (7 cases) or permanent (3 cases). It is essential to emphasize that the initial symptomatology of these patients on their admission to the hospital was often atypical and misleading: in 2 cases, the symptomatology was urological, in 2 cases psychatric and in one digestive. Quantitative determination of catecholamines and their metabolites was positive in 7 cases out of 10. Retropneumoperitoneal insufflation combined with intravenous urography and tomographies provided valuable information in each case. The surgical removal of these tumours, which was unilateral and in normal position, in each case, was carried out without complications. Sudden blood pressure variations observed during the operation could be controlled without difficulty. In 6 patients, the blood pressure became normal and remained so for 4 years. In 2 other patients, the blood pressure came back to normal after the operation, but presented a slight increase 1 year later. Pheochromocytomae, which are often masked by a misleading symptomatology, must be systematically searched for in all hypertensive patients, despite the characteristics of the hypertension. Surgical removal, if done early enough, produces cure of the hypertension.     

Retroviral vector production in the National Gene Vector Laboratory at Indiana University

The National Gene Vector Laboratory (NGVL) is a US National Institutes of Health initiative charged with providing clinical grade vectors for gene therapy trials. The program was started in 1995 and Indiana University has served as the production site for retroviral vectors and is also accepting applications for production of lentiviral vectors. The facility is designed to produce vectors for Phase I and Phase II clinical trials with the specific mandate to facilitate investigator-initiated research for academic institutions. To date, the facility has generated over 30 Master Cell Banks for gene therapy investigators throughout the United States. This required the facility to develop a system that can adapt to the varied needs of investigators, most of whom request different vector backbones, packaging cell lines, final product volumes, and media. In this review, we will illustrate some of the experiences of the Indiana University NGVL during the generation of retroviral vectors using murine-based packaging cell lines.     

Folate supplementation and twinning in patients with sickle cell disease

Patients with sickle cell disease routinely take folic acid daily as a supplement to maintain effective erythropoiesis. One of the controversial effects of folic acid is its effect on twin gestation rates. In this report, we present our experience in patients with sickle cell disease and twin pregnancy. Our data show that twin pregnancies seem to be associated with folate supplementation.     

Hyperhemolysis during the evolution of uncomplicated acute painful episodes in patients with sickle cell anemia

BACKGROUND: Some patients with sickle cell anemia (SS) experience significant decrease in their hemoglobin (Hb) level and significant increase in reticulocyte count during the progression of uncomplicated acute painful episodes. These changes have been attributed to, but not proven, hyperhemolysis. This study provides evidence of hyperhemolysis in this group of patients. STUDY DESIGN AND METHODS: Hospitalized patients who met the above criteria were identified and followed prospectively, and the measures of red blood cell (RBC) survival were determined. The latter included 1) laboratory measures of hemolysis: Hb level, reticulocyte count, nucleated RBC count, RBC distribution width (RDW), total bilirubin, lactate dehydrogenase (LDH), and aspartate transaminase (AST); 2) determination of RBC survival in vivo by the (51)Cr method in selected patients; and 3) the determination of the RBC Hb:reticulocyte Hb ratio. Baseline values of these measures were also obtained and compared to the crisis data. RESULTS: During the evolution of the painful episode in the selected patients, there was a significant increase in total bilirubin, LDH, AST, nucleated RBC count, and RDW that are indicative of hyperhemolysis. There was a significant decrease in RBC Hb:reticulocyte Hb and (51)Cr RBC survival, which is diagnostic of hyperhemolysis. CONCLUSION: Together, the data indicate that hyperhemolysis occurs during uncomplicated acute painful episodes in some patients with SS. The presence of free plasma Hb, consequent to hyperhemolysis, reduces nitric oxide bioavailability, promotes endothelial dysfunction, and contributes to the development of pulmonary hypertension and vasoocclusion.     

Globin chain synthesis in Hb J Baltimore-beta (+)-thalassemia

An American black family in whom hemoglobin J Baltimore and beta (+)-thalassemia genes coexisted is described. The proposita is a 23-year-old woman with a hemoglobin (Hb) level of 11.5 g/dl, microcytic, hypochromic indices, increased values of Hbs A2 and F, and alpha/non-alpha synthetic ratio of 1.52. Hbs A and J Baltimore (beta 16 Gly---Asp) constituted 12% and 81.3%, respectively, of her total hemoglobin. Her sister had a very similar peripheral blood picture, but Hbs A and J Baltimore constituted 6.8% and 85.5%, respectively, of her total hemoglobin, and the alpha/non-alpha synthetic ratio was 1.39. The mother had beta(+)-thalassemia trait only, a moderate degree of anemia, and greater synthetic imbalance (alpha/non-alpha raio of 1.73). These findings suggest that the presence of the Hb J Baltimore gene ameliorates the effects of a coexistent beta-thalassemia gene.     

顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究

对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50～200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。