An immunocytochemical study of the distribution of proline-4- hydroxylase in normal, osteoarthritic and rheumatoid arthritic synovium at both the light and electron microscopic level

The monoclonal antibody 5B5 reacts with the beta subunit of proline-4- hydroxylase, the enzyme which catalyses the formation of 4-hydroxyl proline in collagen and other proteins with collagen-like amino acid sequences. This study aims to assess the production and tissue distribution of this enzyme in normal and diseased synovia from patients with various joint diseases, on the basis that it is a putative marker of collagen-producing cells and, therefore, in this context, of fibroblasts. Sections from five normal, 10 osteoarthritic (OA) and 26 rheumatoid arthritic (RA) synovia were labelled with a mouse monoclonal antibody to proline-4-hydroxylase. The enzyme was found to be expressed by a proportion of synovial intimal cells and by fibroblasts in the underlying connective tissue in normal, OA and RA synovia. Labelling was more pronounced in OA and RA cases. The intimal cells labelling positively showed type B synoviocyte morphology, which was confirmed by subsequent double immunolabelling with 5B5 and antibody against type IV collagen using immunocytochemistry and immunoelectron microscopy.      

替罗非班对糖尿病中危非ST段升高型急性冠脉综合征超敏C反应蛋白和纤维蛋白原的影响

目的:探讨盐酸替罗非班对糖尿病中危非ST段升高急性冠脉综合征（ACS）患者超敏C反应蛋白（hs-CRP）和纤维蛋白原（FIB）的影响。方法:选择住院非ST段升高的ACS患者248例,其中观察组129例,对照组119例,所有患者均首剂服用阿司匹林300 mg、氯吡格雷300 mg,之后阿司匹林100 mg/d、氯吡格雷75 mg/d,在此基础上观察组患者给予静脉输注盐酸替罗非班2～3 d,给予替罗非班期间连用皮下注射低分子肝素（依诺肝素:40 mg/12 h）,停止注射盐酸替罗非班12 h后,继续皮下注射低分子肝素3～4 d[依诺肝素:1 mg/（kg.12h）];对照组患者用低分子肝素[依诺肝素:1 mg/（kg.12h）]皮下注射连续使用5～7 d。测定患者治疗前、治疗后7、30和60 d血浆hs-CRP和FIB并分析其相关性;观察两组中治疗后30 d、60 d内死亡、非致死性心肌梗死、复发性胸痛例数;出血状况。结果:通过治疗两组hs-CRP和FIB水平均逐渐下降。观察组于治疗后7 d hs-CRP和FIB水平开始低于对照组,30 d降低作用最显著,60 d两组hs-CRP和FIB水平差异消失;两组hs-CRP和FIB水平变化呈线性正相关;观察组30 d和60 d的复合缺血事件明显低于对照组;两组临床均无无明显出血事件发生。结论:替罗非班可进一步降低中危ACS伴糖尿病患者的hs-CRP和FIB水平;降低复合缺血事件发生的同时并不增加临床出血事件发生。     

Tolerability of once-weekly alendronate in patients with osteoporosis: a randomized,double-blind,placebo-controlled study

OBJECTIVE: To compare the upper gastrointestinal (GI) tract tolerability of once-weekly oral alendronate, 70 mg, and placebo. PATIENTS AND METHODS: This was a 12-week multicenter, randomized, double-blind, placebo-controlled study. The first patient initiated treatment on June 5, 2000, and the last patient completed treatment on March 1, 2001. The study enrolled 450 postmenopausal women and men with osteoporosis (224 took alendronate, 226 took placebo) who were ambulatory and community dwelling at 48 outpatient study centers in the United States. By design, approximately half of the patients were naive to bisphosphonates. The primary end point was upper GI tract tolerability based on the incidence of any upper GI tract adverse events. Secondary end points included the number of discontinuations due to drug-related upper GI tract adverse events and the change from baseline in bone resorption, assessed by the urinary N-telopeptide-creatinine ratio at 12 weeks. A subgroup analysis of the primary and secondary end points was performed on the patients stratified by prior bisphosphonate use. The safety and tolerability of the weekly alendronate and placebo regimens were captured as clinical and laboratory adverse events. RESULTS: A total of 11% of the alendronate patients and 13% of the placebo patients reported an upper GI tract adverse event. Discontinuations due to drug-related upper GI tract adverse events occurred in 3% of alendronate patients and 1% of placebo patients. The differences between the treatment groups for the primary and secondary end points were not significant. For the primary end point, the upper limit of the 95% confidence interval of the difference was well within the prespecified 14% comparability bound (-2.2%; 95% confidence interval, -8.3% to 3.9%). The overall incidence of upper GI tract adverse events was lower in the subgroup of patients with prior bisphosphonate exposure (8%) than in those who were bisphosphonate naive (16%). However, regardless of prior bisphosphonate exposure, the incidence of upper GI tract adverse events was similar between the alendronate and placebo patients. The urinary N-telopeptide-creatinine ratio showed a significant decrease in the alendronate patients (72% of baseline, P<.001) compared with a slight increase in the placebo patients (106% of baseline) at week 12. CONCLUSION: In this 3-month study, the incidence of upper GI tract adverse events in patients treated with once-weekly alendronate, 70 mg, was comparable to that with placebo.     

The use of ambulatory blood pressure monitoring to evaluate antihypertensive drugs for drug approval

So far, the contribution of clinical studies using ambulatory blood pressure monitoring in the registration of a new antihypertensive agent for marketing authorization purposes has been limited. However, pre-registration studies can be particularly useful, especially to study dose and dose interval in relation to peak: trough ratio during phase II and to facilitate comparison with other antihypertensive agents during phase III of the development of a new antihypertensive agent. More attention should be paid to their design and implementation as high standards are recommended. If properly studied, ambulatory blood pressure monitoring could fulfil a major role in the registration process of a new antihypertensive agent.     

The human homologue of rat NG2, a chondroitin sulfate proteoglycan, is not expressed on the cell surface of normal hematopoietic cells but is expressed by acute myeloid leukemia blasts from poor-prognosis patients with abnormalities of chromosome band 11q23

In our efforts to produce monoclonal antibodies that recognize cell- surface antigens expressed by hematopoietic precursor and stromal cells, we generated a monoclonal antibody, 7.1, which recognizes a 220- to 240-kD cell-surface protein whose N-terminal amino acid sequence is identical to the rat NG2 chondroitin sulfate proteoglycan molecule. This chondroitin sulfate proteoglycan, previously reported to be expressed by human melanoma cells, was not found to be expressed by normal hematopoietic cells, nor was it expressed on the cell surface of cell lines of hematopoietic origin including cell lines with 11q23 abnormalities. It was found on the cell surface of acute myeloid leukemia (AML) blasts and cell lines derived from nonhematopoietic tissues. Samples of leukemic marrow from 166 children with AML enrolled on Childrens Cancer Group protocol 213 were evaluated for cell-surface expression of this proteoglycan molecule. In 18 of 166 (11%) patient samples, greater than 25% of leukemic blasts expressed the NG2 molecule. These 18 patients had a poorer outcome with respect to survival (P = .002) and event-free survival (P = .035) with an actuarial survival at 4 years of 16.7%. Blast cell expression of the NG2 molecule was strongly associated with French-American-British M5 morphology (P < .0001) and abnormalities in chromosome band 11q23, site of the MLL gene. These results show that the NG2 molecule is expressed by malignant hematopoietic cells that have abnormalities in chromosome band 11q23, suggesting that antibody 7.1 may be useful in the rapid identification of this group of poor-prognosis patients.     

Hemodynamic characteristics of the intestinal microcirculation in renal hypertension

This study investigated the microvascular changes that affect vascular resistance in the rat small intestine during two-kidney, one clip renal hypertension 4 weeks after renal artery stenosis. To study the intestinal microcirculation, a loop of the small intestine was exteriorized with intact circulation and innervation and a section of the bowel wall was prepared for observation with an intravital video microscopy system. Microvascular diameter, pressure, and flow velocity were measured for first, second, and third branch order arterioles and venules, using an image shearing monitor, servo-null micropipette system, and an optical Doppler velocimeter, respectively. The diameters of the first order arterioles and venules were significantly (p less than 0.05) reduced in hypertensive rats; however, diameters were unaltered in smaller second and third order arterioles and venules as compared with normotensive vessels. In hypertensive rats, mean arterial pressure was significantly (p less than 0.05) elevated (47%) and pressures also were elevated significantly (p less than 0.05) throughout the microcirculation, although by a proportionally smaller amount. Total network flow (i.e., first order arteriole flow) was significantly (p less than 0.05) reduced (40%) in hypertensive rats, but volume flows in individual second and third order arterioles were similar to flows measured in normotensive rats. Calculated total network resistance was increased (124%) in hypertensive rats. Thus, the intestinal microcirculation in rats with two-kidney, one clip renal hypertension is disturbed by elevated pressure and decreased total flow. The presence of normal flows in individual second and third order arterioles without any demonstrable difference in their diameters suggests that the predominant cause of elevated resistance across this segment of the intestinal microcirculation is a reduction in the number of perfused small arterioles.     

Protein sequencing by tandem mass spectrometry.

Methodology for determining amino acid sequences of proteins by tandem mass spectrometry is described. The approach involves enzymatic and/or chemical degradation of the protein to a collection of peptides which are then fractionated by high-performance liquid chromatography. Each fraction, containing as many as 10-15 peptides, is then analyzed directly, without further purification, by a combination of liquid secondary-ion/collision-activated dissociation mass spectrometry on a multianalyzer instrument. Interpretation of collision-activated dissociation mass spectra is described, and results are presented from a study of soluble peptides produced by treatment of apolipoprotein B with cyanogen bromide and trypsin.     

Increased red blood cell deformability due to isoxsuprine administration decreases platelet adherence in a perfusion chamber: a double-blind cross-over study in patients with intermittent claudication

Platelet transport towards the vessel wall is influenced by the hematocrit, red blood cell (RBC) size, and shape. Recent in vitro studies have indicated that RBC deformability may also influence platelet transport. The observation that isoxsuprine, a known vasodilating drug, caused increased RBC deformability in vitro and decreased platelet transport in vitro prompted us to study the effects of this drug in vivo. The study was performed in a double-blind cross- over study of isoxsuprine v placebo in ten patients with peripheral arterial insufficiency. RBC deformability was estimated from viscosity measurements using the blood viscosity equation of Dintenfass and expressed as T value. Platelet transport was studied in an annular perfusion chamber according to Baumgartner. Human umbilical arteries were used as blood vessels. Perfusion studies were performed with whole blood or with RBCs of the patients mixed with normal platelets and plasma at a standardized hematocrit and platelet count. An increase in RBC deformability concomitant with a decrease in platelet adherence was observed in patients on isoxsuprine with a drop in T value of approximately 0.06 (from 0.91 toward 0.86), and a concomitant decrease in platelet adherence of 20% to 40%. These observations differed significantly from the results in the placebo group and showed a significant group-period interaction at the cross-over of medication (analysis of variance). The effects on platelet adherence were observed at high vessel wall shear rate (1,800 s-1) with perfusates consisting of patients' RBCs and donor plasma and platelets at standardized hematocrit and platelet count. No differences were observed under these conditions at a shear rate of 300 s-1. When whole blood of patients was used, nonsignificant effect was observed at shear rates of 300 s-1 and 1,800 s-1. This was probably caused by the added noise due to variations in hematocrit and platelet number. These data demonstrate that isoxsuprine increases RBC deformability, and they suggest the possibility of decreasing platelet-vessel wall interaction in vivo by manipulation of RBC deformability.     

Acute lymphoblastic leukemia in infants: evidence for B cell origin of disease by use of monoclonal antibody phenotyping

Since the prognosis of infants with acute lymphoblastic leukemia (ALL) is so poor, it has been suggested that these leukemias may not be lymphoid in origin, but may originate from stem cell, myeloid, or megakaryocytic progenitors. Alternately it has been hypothesized that these leukemias originate in lymphoid cells at the earliest stages of B cell development. Another possibility is that these leukemias may be of more than one lineage. Therefore we examined leukemic blasts from 12 infants with ALL using monoclonal antibodies to myeloid and lymphoid differentiation antigens. The majority of specimens expressed HLA/DR and reacted with B4 (CD19) but failed to react with stem cell, myeloid, megakaryocytic, or T cell associated antibodies. These results support the speculation that the majority of these leukemias arise in cells at the earliest stages of B cell commitment, and are not of a myeloid or biphenotypic nature.     

Effects of coronary artery surgery on left ventricular performance, segmental wall movement, and exertional ischaemia

The effects of coronary artery surgery on left ventricular performance were assessed serially by echocardiography and treadmill exercise testing in 54 patients. Patients were assessed one day before operation and again before patients left hospital (mean 10 days after operation) and one month and six months after operation. At the predischarge assessment, 41 (77%) patients showed new abnormalities of left ventricular segmental wall movement, chiefly anteroseptal hypokinesia with hyperkinesia of the posterolateral segment. Although there were no significant changes in anteroseptal wall thickening after operation, there was a significant increase in posterior wall thickening at all postoperative assessments. The frequency of this abnormality decreased progressively after operation; it persisted in 19 (35%) patients at six months. Left ventricular fractional shortening decreased after operation and at one month was significantly less than before operation. There were no significant changes in left ventricular diastolic diameter during the study. Haemodynamic function during exercise, the duration of exercise, and features of reversible myocardial ischaemia all improved progressively and significantly after coronary artery surgery. Abnormalities in left ventricular segmental wall movement and thickening commonly develop early after coronary artery surgery but tend to resolve by six months and do not seem to impair left ventricular contractility at rest or exercise performance and haemodynamic function. Recognition of these echocardiographic changes may be clinically important in the assessment of patients after cardiac surgery.