Collective cancer cell invasion induced by coordinated contractile stresses

The physical underpinnings of fibrosarcoma cell dissemination from a tumor in a surrounding collagen-rich matrix are poorly understood. Here we show that a tumor spheroid embedded in a 3D collagen matrix exerts large contractile forces on the matrix before invasion. Cell invasion is accompanied by complex spatially and temporally dependent patterns of cell migration within and at the surface of the spheroids that are fundamentally different from migratory patterns of individual fibrosarcoma cells homogeneously distributed in the same type of matrix. Cells display a continuous transition from a round morphology at the spheroid core, to highly aligned elongated morphology at the spheroid periphery, which depends on both β₁-integrin-based cell-matrix adhesion and myosin II/ROCK-based cell contractility. This isotropic-to-anisotropic transition corresponds to a shift in migration, from a slow and unpolarized movement at the core, to a fast, polarized and persistent one at the periphery. Our results also show that the ensuing collective invasion of fibrosarcoma cells is induced by anisotropic contractile stresses exerted on the surrounding matrix.     

Endocrine Function, Psychiatric and Clinical Consequences in Patients With Macroprolactinomas After Long-term Treatment With the New Non-ergot Dopamine Agonist CV205-502

Although bromocriptine is the mainstay of treatment of macroprolactinomas,its therapeutic usefulness may be limited by poor tolerance,lack of consistent reduction in serum prolactin levels and tumoursize, and the necessity for multiple dosing. Consequently newdopamine agonists have been developed, including the long actingnon-ergot agonist CV205–502 which has been shown to dateto be consistently effective in reducing serum PRL levels andcausing tumour shrinkage. Twelve patients were treated for periods of up to 24 monthswith CV205–502 in doses ranging from 0.075 mg to 1.65mg once daily. Clinical and psychiatric assessments, biochemicalparameters, tumour size determination, and anterior pituitaryfunction tests were performed regularly. Tumour shrinkage wasnoted in all patients, and varied from 11 per cent reductionto complete disappearance of tumour. Prolactin levels becamenormal in seven patients and were reduced by more than 90 percent in the remaining five. Normal menstruation resumed in sixof the eight women, one of whom conceived after one year oftherapy; libido returned in all patients. Psychiatric complicationsoccurred in three patients necessitating withdrawal of therapyin one. Significant weight loss was noted in 11 of 12 patients. Triglyceride concentrations fell from 1.5±0.1 to 1.0±0.1mmol/l at 12 months (p=0.006), and cholesterol fell from 6.3±0.4to 5.3±0.3 mmol/l (p=0.04). The mean TSH response 20min following TRH injection fell from 14.3±2.9 to 8.7±1.3mU/l at 2 months (p=0.027). There was a significant increasein the peak growth hormone response to the insulin stress testfrom basal median (25th–75th centiles) values of 15 (4.4–25.5)mU/l to 24.5 (9–37) mU/l at 2 months (p<0.01) and 31(19.3–63.5) at 12 months (p<0.005). CV205–502 is highly effective in the medical managementof patients with macroprolactinomas, reducing prolactin levelsand tumour size and restoring normal anterior pituitary function.It is, however, associated with the important side effects ofweight loss and pychiatric complications which should be drawnto the attention of clinicians.     

Measurement of free drug in phase I: is it useful?

Summary— Early investigation of protein binding of a new drug is mandatory. The following questions have to be answered: is unbound fraction constant over tested concentrations? Which proteins are involved? What are the binding parameters? Can the drug compete with other therapeutic agents for the binding sites or in other words can drug displacements be predicted? What is the interindividual variability in protein binding? Is the binding stereoselective? All this information is necessary in predicting the pharmacokinetic behaviour of the drug and in assisting in the design of future pharmacokinetic protocols in phases II and III. The use of free drug concentration should also be considered when comparing the bioavailability of regular vs sustained release dosage forms of drugs exhibiting concentration-dependent binding and when studying concentration-effect relationships.     

脐血单个核细胞成功培养的相关影响因素

目的:脐血来源丰富且免疫原性低,移植后排斥反应低的特性决定其具有临床应用的可行性。实验拟验证脐血单个核细胞数量与孕妇年龄条件、脐血量及制备因素的相关性,并证实其在体外培养的最佳条件。方法:实验于2006-03/2007-01在辽宁省血液中心输血医学研究所细胞研究中心完成。①实验材料:300份脐血均来源于足月分娩的健康孕妇,全部签署知情同意书。孕妇年龄20～35岁,其中≤25岁36例,>25岁264例;脐血采集量15～130mL,其中<33mL18例,≥33mL282例;采集到制备时间差为2～24h,其中>12h30例,≤12h270例。红细胞裂解液由本实验室自制,主要成分为高渗盐水和三蒸水。②实验方法:人脐血用枸橼酸钠抗凝,采用密度梯度离心法分离得到脐血单个核细胞,锥虫蓝染色结果表明活细胞比率达95%～100%。将脐血单个核细胞分别按1×106,5×106,1×107的密度接种,以未加细胞因子作为对照组,在无血清DMEM/F12培养液中加入20μg/L神经生长因子和2%神经营养因子B27作为扩增诱导组,于培养后的1,3,7d进行换液,培养周期选择5d、7～10d和15d。③实验评估:分别对脐血单个核细胞数与孕妇年龄、脐血采集量、采集到制备时间差的相关性进行分析。倒置荧光显微镜下观察细胞形态、细胞因子作用及最佳的种植密度、首次换液时间、培养周期。观察使用红细胞裂解液后对脐血单个核细胞增殖和分化的影响。结果:①脐血细胞的生长及形态特征:脐血单个核细胞刚接种时为散在的圆形细胞,2d贴壁,为散在的单个或数个细胞,呈长梭形,形态均一。3d左右细胞突起增加,细胞数量增多。随着培养时间的延长,可见多个细胞之间形成网络,诱导后出现神经样细胞形态。②脐血单个核细胞数的影响因素:脐血单个核细胞数与孕妇年龄不相关(r<0.3),与脐血量、采集到制备时间差均具有相关性(r>0.8)。③脐血单个核细胞培养影响因素:种植密度为5×106L-1、首次换液时间在3d左右、培养周期为7～10d的细胞生长状态较好。扩增诱导组脐血单个核细胞增殖和分化状态好于对照组。④红细胞对脐血单个核细胞生长分化的影响:红细胞裂解的最佳时间为45～50s,并发现红细胞对脐血单个核细胞的生长有一定程度影响,且破骨细胞较多。红细胞裂解后的脐血单个核细胞增殖分化较好,细胞形态较为均一。结论:①采集量为33mL、且采集到制备的时间差为12h的脐血制备单个核细胞数量超过1×108的成功例数较高。②5×106L-1接种密度、首次换液时间为3d、培养周期7～10d的脐血单个核细胞生长状态较好,神经细胞生长因子可促进其增殖分化。③红细胞裂解后脐血单个核细胞增殖分化更好,破骨细胞较少。     

Clinical studies of multiple endocrine neoplasia type 1 (MEN1) [published erratum appears in QJM 1996 Dec;89(12):957-8]

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the combined occurrence of parathyroid, pancreatic islet and anterior pituitary tumours. To facilitate a screening programme for MEN1, we investigated 709 people (364 males and 345 females, age range 1-84 years) from 62 MEN1 families, and 36 non- familial MEN1 patients. Of those investigated, 220 (95 males and 125 females, age range 8-79 years) suffered from MEN1. Parathyroid, pancreatic and pituitary tumours occurred in 95%, 41% and 30% of the patients, respectively. Parathyroid tumours were the first manifestation of MEN1 in 87% of patients, and amongst the pituitary and pancreatic tumours, somatotrophinomas and gastrinomas were more common in patients above the age of 40 years, whilst insulinomas occurred more frequently in patients below the age of 40 years. Biochemical screening indicated that the penetrance of MEN1 by the ages of 20, 35 and 50 years was 43%, 85% and 94%, respectively, and that the development of MEN1 was confined to first-degree relatives in 91% of patients and to second-degree relatives in 9% of patients. These findings have helped to define a proposed screening programme for MEN1.      

退变性第4腰椎椎体滑脱治疗中精确预弯钛棒的可行性分析

目的:用钉-棒内固定系统治疗退变性腰椎滑脱时,术中反复折棒会降低钛棒抗疲劳性并延长手术时间。分析折棒的影响因素并依据术前影像学显示的腰前凸角、滑脱角和滑移百分比探讨精确预折弯钛棒的可行性。方法:选择2006-02/09新疆自治区中医医院脊柱外科病房收治的31例Ⅰ度、Ⅱ度(Meyerding分度)退变性L4椎体滑脱需手术治疗的患者,均为女性,年龄40～70岁,平均58.3岁。测量术前腰前凸角、滑脱角和滑移百分比,术中置入依据相应标准折弯的钛棒,将研究对象假想为刚体,建立应变量(折棒角)与自变量(腰前凸角、滑脱角、滑移百分比)的多元线性回归方程,对各变量进行统计学分析与评价。数据的统计分析用SPSS13.0软件包处理结果:31例均进入结果分析。折棒角度与腰前凸角、滑脱角及椎体滑移百分比有相关性,多元线性回归方程:Y(折棒角)=0.1390-0.32756logx1(术前腰前凸角) 0.463689x2(术前滑脱角) 0.288186x32(术前滑移百分比),经方差分析方程有统计学意义(F=7.708,P=0.001)。常数0.1390有统计学意义(P=0.000477),x1的回归系数-0.32756有统计学意义(P=0.028383),x2的回归系数0.463689有统计学意义(P=0.003096),x3的回归系数0.288186有统计学意义(P=0.047435),决定系数R2=0.704257。结论:折棒角与腰前凸角、滑脱角、滑移百分比有相关性,折棒角变化的70.43%可由术前腰前凸角、滑脱角和滑移百分比来解释。术前将钛棒预弯成较精确的弯度,从而减小钛棒损耗是可行的。     

A pilot study of continuous ambulatory electrocardiography in patients donating blood for autologous use in elective coronary artery bypass grafting

BACKGROUND: A pilot study was conducted to evaluate the impact of a single autologous blood donation on the presence or absence of myocardial ischemic episodes in patients with coronary artery disease. STUDY DESIGN AND METHODS: Fifty patients scheduled for elective coronary artery bypass grafting underwent two 24-hour periods of ambulatory electrocardiogram monitoring, one before and one after their first autologous blood donation. The presence or absence and the number, duration, and integral area of episodes of ST segment depression for each 24-hour monitoring period were determined. RESULTS: Forty-two patients had legible electrocardiogram recordings for both monitoring periods. Of these, 36 patients (86%) had at least one episode of ST segment depression during any monitoring period. The number of patients who had at least one episode of ST segment depression before donation was not significantly different from the number of those who had at least one episode after donation (31 and 33 patients, respectively; p = 0.73). CONCLUSION: Donating a unit of blood had no demonstrable effect on the presence or absence of myocardial ischemic episodes in this sample of 42 autologous blood donors with coronary artery disease. The results of this study should be validated in further trials.     

Direct demonstration of an HLA-DR allotypic determinant on the low molecular weight (beta) subunit using a mouse monoclonal antibody specific for DR3

A murine monoclonal antibody directed against a human B cell surface antigen with the characteristics of HLA-DR is described. The antigen detected is tightly linked to HLA and is correlated with the alloantigen HLA-Dw/DR3. Reactivity with a fraction of Dw/DRw6 cells is also observed. The determinant recognized by this antibody has been shown to be present on the smaller molecular weight β subunit of the HLA-DR antigen.     

A multicenter study on the efficiency of white cell reduction by filtration of red cells

To evaluate accurately the current performance of filtration, the French Produits Sanguins Labiles study group, composed of 21 transfusion teams, conducted a large-scale 6-month study involving over 1400 filtrations and 3000 controls. Some 745 standard red cell concentrates (RBC concentrates) and 690 concentrates previously white cell (WBC)-reduced by removal of buffy coat (BC-poor RBC concentrates) were filtered using six commercially available filters: at least 170 results were collected per filter, spread among a minimum of three teams. Prefiltration controls show that the removal (manual and automated) of the buffy coat results in an initial WBC reduction of approximately 63 percent, along with a hemoglobin loss of 4 g (7%). After filtration, residual WBCs were counted in the Nageotte manual counting chamber. The reliability of this counting method, which is simple and adapted to low WBC concentrations, was characterized in this study by a 25-percent coefficient of variation (CV) for a concentration of 2.5 WBCs per microL (i.e, 0.6 x 10(6) WBCs/filtered unit). The analysis of the results shows that, for five of six filters (1 filter was excluded), the postfiltration median value of residual WBCs was 1.1 x 10(6) in filtered RBC concentrates (n = 590), whereas it was 0.34 x 10(6) in filtered BC-poor RBC concentrates (n = 581). The difference is significant (p less than 10(-8), Wilcoxon test). Hemoglobin loss due to filtration varies according to the filter, from 5.7 +/- 2.2 to 17.3 +/- 2.5 g.(ABSTRACT TRUNCATED AT 250 WORDS)     

Abnormal membrane physical properties of red cells in McLeod syndrome

McLeod red cells (RBCs) lack Kx antigens and have weak expression of the Kell antigens. Individuals who carry the McLeod phenotype have acanthocytic RBCs and a compensated hemolytic state. To elucidate the role of the protein on which the Kx antigens reside in maintaining membrane deformability, the rheologic properties of McLeod RBCs were determined by ektacytometry. RBCs were obtained from normal individuals and from four patients with McLeod syndrome. Osmotic gradient deformability profiles of McLeod RBCs showed decreased whole cell deformability. Resealed ghosts from McLeod RBCs also showed decreased deformability, partly because of the decreased cell surface area and partly because of an intrinsic membrane stiffness in this syndrome. For the measurement of membrane mechanical stability, resealed ghosts were subjected to constant high shear stress in the ektacytomer, and deformability was recorded continuously as the deformable ghosts fragmented into rigid spherical vesicles. Membranes from McLeod RBCs showed a noticeable increase in mechanical stability. Acquired causes of acanthocytosis, such as liver disease, did not cause the rheologic abnormalities observed in McLeod cells. Other abnormalities noted in McLeod RBCs were decreased RBC potassium content and an increased number of dense RBCs, as determined by centrifugation on a discontinuous density gradient. The data indicate that McLeod RBCs are rigid and have decreased surface area and that their membranes are intrinsically rigid with increased mechanical stability. These abnormalities may account for the reduced RBC survival observed in McLeod syndrome. The protein that carries the Kx surface antigen seems to be required for the maintenance of the normal physical function of RBC skeletal proteins.