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111.
Neonatal neutrophils (PMN) show a well-documented defect in chemotaxis that is associated with several abnormalities of PMN structure and function, including deficient surface expression of CR3 (CD11b), a critical adhesion molecule, on chemoattractant-activated PMN. After activation of PMN with additional stimuli including calcium ionophores, we also found deficient surface CR3 (but normal CR1) expression on neonatal PMN suggesting that abnormal signaling mechanisms are not likely to explain the deficient CR3 expression on activated neonatal PMN. Therefore, we hypothesized that deficient surface expression of CR3 on stimulated neonatal neutrophils is caused by a deficiency in total cell content of CR3. We tested this hypothesis using three different methods to compare the total quantity of CR3 in neonatal versus adult PMN. Western blotting of serial twofold dilutions of PMN lysates from five adult and neonatal pairs, using a monoclonal antibody (MoAb) against CR3 (21PM19C), consistently showed diminished CR3 content in neonatal PMN. A sandwich enzyme-linked immunosorbent assay, in which the CR3 heterodimers in PMN lysates were captured by MoAb to the beta-chain, CD18 (R15.7), then detected with a biotinylated MoAb to the alpha-chain, CD11b (anti-Mac-1), showed that neonatal PMN lysates contain about 66% of adult PMN levels of CR3 (P < 0.03; n = 6). PMN fixed with paraformaldehyde and permeabilized with saponin were studied by immunofluorescence flow cytometry to determine total (surface plus intracellular) CR3 content using phycoerythrin-conjugated MoAb to CR3 (anti-Leu15). Mean total cell CR3 content (in relative fluorescence units) was 58 +/- 14 for adult PMN and 27 +/- 6 for neonatal PMN (n = 5; P = 0.013). In each method, total cell content of CR1 was equivalent for neonatal versus adult PMN. We conclude that neonatal PMN are markedly deficient in total cell CR3 content compared with adult PMN. This result provides a primary explanation for deficient CR3 surface expression on activated neonatal PMN that, in turn, may be important in the chemotactic defect of these cells. 相似文献
112.
Globular adiponectin increases GLUT4 translocation and glucose uptake but reduces glycogen synthesis in rat skeletal muscle cells 总被引:10,自引:0,他引:10
Aims/hypothesis The aim of this study was to determine whether adiponectin elicits glucose uptake via increased GLUT4 translocation and to investigate the metabolic fate of glucose in skeletal muscle cells treated with globular adiponectin.Materials and methods Basal and insulin-stimulated 2-deoxy-d-[3H]glucose uptake, cell surface myc-tagged GLUT4 content, production of 14CO2 by oxidation of d-[U-14C]glucose and [1-14C]oleate, and incorporation of d-[U-14C]glucose into glycogen and lactate were measured in the presence and absence of globular adiponectin.Results RT-PCR and Western blot analysis revealed that L6 cells and rat skeletal muscle cells express AdipoR1 mRNA and protein. Globular adiponectin increased both GLUT4 translocation and glucose uptake by increasing the transport Vmax of glucose without altering the Km. Interestingly, the incorporation of d-[U-14C]glucose into glycogen under basal and insulin-stimulated conditions was significantly decreased by globular adiponectin, whereas lactate production was increased. Furthermore, globular adiponectin did not affect glucose oxidation, but enhanced phosphorylation of AMP kinase and acetyl-CoA carboxylase, and fatty acid oxidation.Conclusions/interpretation The present study is the first to show that globular adiponectin increases glucose uptake in skeletal muscle cells via GLUT4 translocation and subsequently reduces the rate of glycogen synthesis and shifts glucose metabolism toward lactate production. These effects are consistent with the increased phosphorylation of AMP kinase and acetyl-CoA carboxylase and oxidation of fatty acids induced by globular adiponectin. 相似文献
113.
Antonino Tuttolomondo Rosaria Pecoraro Alessandra Casuccio Domenico Di Raimondo Carmelo Buttà Giuseppe Clemente Vittoriano della Corte Giuliana Guggino Valentina Arnao Carlo Maida Irene Simonetta Rosario Maugeri Rosario Squatrito Antonio Pinto 《Medicine》2015,94(20)
CD4+ CD28− T cells also called CD28 null cells have been reported as increased in the clinical setting of acute coronary syndrome. Only 2 studies previously analyzed peripheral frequency of CD28 null cells in subjects with acute ischemic stroke but, to our knowledge, peripheral frequency of CD28 null cells in each TOAST subtype of ischemic stroke has never been evaluated. We hypothesized that CD4+ cells and, in particular, the CD28 null cell subset could show a different degree of peripheral percentage in subjects with acute ischemic stroke in relation to clinical subtype and severity of ischemic stroke.The aim of our study was to analyze peripheral frequency of CD28 null cells in subjects with acute ischemic stroke in relation to TOAST diagnostic subtype, and to evaluate their relationship with scores of clinical severity of acute ischemic stroke, and their predictive role in the diagnosis of acute ischemic stroke and diagnostic subtypeWe enrolled 98 consecutive subjects admitted to our recruitment wards with a diagnosis of ischemic stroke. As controls we enrolled 66 hospitalized patients without a diagnosis of acute ischemic stroke. Peripheral frequency of CD4+ and CD28 null cells has been evaluated with a FACS Calibur flow cytometer.Subjects with acute ischemic stroke had a significantly higher peripheral frequency of CD4+ cells and CD28 null cells compared to control subjects without acute ischemic stroke. Subjects with cardioembolic stroke had a significantly higher peripheral frequency of CD4+ cells and CD28 null cells compared to subjects with other TOAST subtypes. We observed a significant relationship between CD28 null cells peripheral percentage and Scandinavian Stroke Scale and NIHSS scores. ROC curve analysis showed that CD28 null cell percentage may be useful to differentiate between stroke subtypes.These findings seem suggest a possible role for a T-cell component also in acute ischemic stroke clinical setting showing a different peripheral frequency of CD28 null cells in relation of each TOAST subtype of stroke. 相似文献
114.
Vincenzo Bottino Maria Grazia Esposito Arianna Mottola Giampaolo Marte Vittorio Di Maio Valerio Sciascia Marco Nunziante Giovanni Fregola Salvatore Cuzzovaglia Francesco Galante Federica Andreoli Alfredo Breglia Maria Elena Giuliano Domenico Papaleo Paola Della Rocca Pietro Maida 《BMC surgery》2012,12(Z1):S8
Background
The aim of this study was to define any benefits in terms of early outcome for laparoscopic colectomy in patients over 75 years old (OP) compared with the outcomes of a younger populations (YP).Methods
Forty elderly patients undergoing laparoscopic colectomy for colorectal cancer between 2007-2011 were studied, the patients are divided for gender, age, year of surgery, site of cancer, and comorbidity on admission and compared with 40 younger patients.Results and discussion
Mean (standard deviation) age was 81.3 in OP and 68.3 YP Conversion rate was the same between the two groups. There was no difference in operative mean time . The overall mortality rate was 0% percent. The surgical morbidity rate was the same but there was an increased in cardiologic e bronchopneumonia complications in older population. Patients treated with laparoscopic approach had a faster recovery of bowel function and a significant reduction of the mean length of hospital stay not age related. Laparoscopy allowed a better preservation of postoperative independence status.Conclusions
Laparoscopic colectomy for cancer in elderly patients is safe and beneficial including preservation of postoperative independence and a reduction of length of hospital stay.115.
Giuseppe Cabibbo Marcello Maida Chiara Genco Pietro Parisi Marco Peralta Michela Antonucci Giuseppe Brancatelli Calogero Cammà Antonio Craxì Vito Di Marco 《World journal of hepatology》2012,4(9):256-261
AIM:To investigate the clinical course of untreatable hepatocellular carcinoma(HCC) identified at any stage and to identify factors associated with mortality.METHODS:From January 1999 to December 2010,320 out of 825 consecutive patients with a diagnosis of HCC and not appropriate for curative or palliative treatments were followed and managed with supportive therapy.Cirrhosis was diagnosed by histological or clinical features and liver function was evaluated according to Child-Pugh score.The diagnosis of HCC was performed by Ultra-Sound guided biopsy or by multiphasic contrast-enhanced computed tomography or gadolinium-enhanced magnetic resonance imaging.Data were collected for each patient including all clinical,laboratory and imaging variables necessary for the outcome prediction staging systems considered.HCC staging was performed according Barcelona Clinic Liver Cancer(BCLC) and Cancer of the Liver Italian Program scores.Follow-up time was defined as the number of months from the diagnosis of HCC to death.Prognostic baseline variables were analyzed by multivariate Cox analysis to identify the independent predictors of survival.RESULTS:Seventy-five per cent of patients had hepatitis C.Ascites was present in 169 patients(53%),while hepatic encephalopathy was present in 49 patients(15%).The Child-Pugh score was class A in 105 patients(33%),class B in 142 patients(44%),and class C in 73 patients(23%).One hundred patients(31%) had macroscopic vascular invasion and/or extrahepatic spread of the tumor.A single lesion 10 cm was observed in 34 patients(11%),while multinodular HCC was present in 189 patients(59%).Thirty nine patients(12%) were BCLC early(A) stage,55(17%) were BCLC intermediate(B) stage,124(39%) were BCLC advanced(C) stage,and 102(32%) were endstage BCLC(D).At the time of this analysis(July 2011),28(9%) patients were still alive.Six(2%) patients who were lost during follow-up were censored at the last visit.The overall median survival was 6.8 mo,and the 1-year survival was 32%.The 1-year survival according to BCLC classes was 100%,79%,12% and 0%,for BCLC A,B,C and D,respectively.There was a significant difference in survival between each BCLC class.The median survival of patients of BCLC stages A,B,C and D was 33,17.4,6.9,and 1.8 mo,respectively(P 0.05 for comparison between stages).The median survival of Child-Pugh A,B and C classes were 9.8 mo(range 6.4-13),6.1(range 4.9-7.3),and 3.7(range 1.5-6),respectively(P 0.05 for comparison between stages).By univariate analysis,the variables significantly associated to an increased liklihood of mortality were Eastern Cooperative Oncology Group performance status(PS),presence of ascites,low level of albumin,elevated level of bilirubin,international normalized ratio(INR) and Log-[(α fetoprotein(AFP)].At multivariate analysis,mortality was independently predicted by bad PS(P 0.0001),high INR values(P = 0.0001) and elevated Log-(AFP) levels(P = 0.009).CONCLUSION:This study confirms the heterogeneous behavior of untreated HCC.BCLC staging remains an important prognostic guide and may be important in decision-making for palliative treatment. 相似文献
116.
Groopman JE; Hartzband PI; Shulman L; Salahuddin SZ; Sarngadharan MG; McLane MF; Essex M; Gallo R 《Blood》1985,66(3):742-744
The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-III. We report the first two cases, one with AIDS and one with ARC, that are HTLV-III virus positive but antibody negative. Accurate diagnosis of HTLV-III infection in some cases may require direct virus culture or tests for antigen. In addition, lack of HTLV-III antibody may indicate an atypical clinical course of AIDS. 相似文献
117.
CD34 expression is regulated reciprocally with adhesion molecules in vascular endothelial cells in vitro 总被引:11,自引:1,他引:11
Delia D; Lampugnani MG; Resnati M; Dejana E; Aiello A; Fontanella E; Soligo D; Pierotti MA; Greaves MF 《Blood》1993,81(4):1001-1008
Freshly cultured vascular endothelial cells express the CD34 antigen in a diffuse cell surface pattern with some concentration on microvilli. Expression is downregulated with proliferation in continuous culture and undetectable after nine population doublings but can be maintained by restraining cell proliferation and promoting cell contact. Expression of CD34 at the antigen and mRNA levels on early passage cells is rapidly downregulated by interleukin-1 beta (IL-1 beta), interferon-gamma (INF-gamma), and tumor necrosis factor-alpha (TNF- alpha) under conditions in which these ligands upregulate the adhesion molecules: endothelial leukocyte adhesion molecule 1 (ELAM-1) and intracellular adhesion molecule 1 (ICAM-1). This reciprocal pattern of expression and the topographic distribution of CD34 molecules on the lumenal interdigitated microprocesses of adjacent endothelial cells in vivo suggest that CD34 might have a negative modulating role on adhesion functions of endothelia. 相似文献
118.
Prognostic significance of bcl-2 protein expression in aggressive non- Hodgkin's lymphoma. Groupe d'Etude des Lymphomes de l'Adulte (GELA) 总被引:9,自引:16,他引:9
Hermine O; Haioun C; Lepage E; d'Agay MF; Briere J; Lavignac C; Fillet G; Salles G; Marolleau JP; Diebold J; Reyas F; Gaulard P 《Blood》1996,87(1):265-272
119.
120.
The biochemical and clinical consequences of 2'-deoxycoformycin in refractory lymphoproliferative malignancy 总被引:4,自引:1,他引:4
Grever MR; Siaw MF; Jacob WF; Neidhart JA; Miser JS; Coleman MS; Hutton JJ; Balcerzak SP 《Blood》1981,57(3):406-417
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration. 相似文献