The metabolite 1 alpha,25-dihydroxyvitamin D3 enhances lymphokine- mediated activation of the oxidative metabolism of the U937 cell line and phosphorylation of a 48-kD respiratory burst-associated protein

U937 cells respond to a variety of stimuli with increased differentiation as manifested by reduced growth, increased adherence, increased expression of several surface receptors, and increased capacity for phagocytosis and formation of reactive oxygen intermediates. In the present study the effects of lymphocyte conditioned media, recombinant interferon-gamma (IFN-gamma), and 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the ability to form reactive oxygen intermediates by U937 cells were measured by using the luminol-dependent luminescence (LDL) assay. Neither 1,25(OH)2D3 alone nor IFN-gamma alone enhanced competence for phorbol myristate acetate- stimulated LDL. Cells were capable of moderate LDL after exposure to lymphocyte conditioned media, and this was enhanced by 1,25(OH)2D3 (10(- 8) mol/L) and other vitamin D metabolites at higher concentrations. This effect was not secondary to accelerated production of myeloperoxidase, which is important in the LDL assay. Enhanced phorbol myristate acetate-stimulated phosphorylation of a 48-kd substrate was observed in 32P-labeled intact cells treated with 1,25(OH)2D3 alone or in combination with IFN-gamma. Treatment of cells with IFN-gamma or lymphocyte conditioned media did not alter phosphorylation. These results support the concept that 1,25(OH)2D3 plays a role in phagocyte differentiation and activation beyond the effects of lymphokines. Protein kinase C-mediated phosphorylation reactions may be necessary for the ability of U937 cells to reduce O2 and required for maximal activity under some conditions of incubation.     

Pathology of human intestinal transplantation

BACKGROUND & AIMS: Intestinal transplantation is a developing therapeutic option for patients with irreversible intestinal failure or short bowel syndrome. The aim of this study was to delineate the histopathology of human intestinal allografts and to define the features of intestinal rejection. METHODS: The histological features of 3015 endoscopic biopsy specimens and 23 allograft specimens from 62 intestinal recipients were analyzed retrospectively and correlated with clinical findings. RESULTS: Acute allograft rejection was characterized by a varying combination of crypt injury, mucosal infiltration primarily by mononuclear cells (including blastic lymphocytes), and increased crypt cell apoptosis (more than 2 per 10 crypts). It represented a patchy, often ileal-centered process that could progress to mucosal ulceration; later episodes (more than 100 days posttransplant) tended to show lesser cellular infiltration and greater apoptosis than earlier episodes. Correlation with clinical rejection was good (false-positive rate of 9%; false-negative rate of 26%). Two resected specimens showed obliterative arteriopathy indicative of chronic rejection. In other specimens, preservation injury, cytomegalovirus infection, post-transplant lymphoproliferative disorder, and nonspecific features of active or past mucosal injury could be recognized. CONCLUSIONS: Mucosal biopsy specimens are a useful means of monitoring intestinal allografts. Based on features validated by clinical correlation, acute rejection can be identified reliably and can be differentiated from the other pathological processes affecting the intestinal allograft. (Gastroenterology 1996 Jun;110(6):1820-34)     

Bile duct stones: percutaneous transhepatic removal

Percutaneous transhepatic intervention for transduodenal removal of biliary stones was performed 38 times in 34 patients with obstructive jaundice, biliary colic, and cholangitis. The technique entailed the percutaneous transhepatic placement of a modified Dormia basket in the common duct with the flexible tip in the duodenum. The stones were passed into the duodenum and were crushed, or were crushed in the common duct and passed as fragments into the duodenum. In addition to the snare procedure, monooctanoin was used 18 times to dissolve remaining fragments of stone and sludge that could not be snared and passed into the duodenum. The average time for completion of the procedure was 10 days. There were no deaths from the procedure. The complication rate was 21%--probably no greater than would occur with surgery in a similar patient population. The procedure can be performed when endoscopic retrograde cholangiopancreatography and sphincterotomy with stone removal is technically impossible or refused, and in patients who have previously undergone choledochojejunostomy.     

赛拉嗪对麻醉大鼠海马CA1区乙酰胆碱含量的影响

应用乙酰胆碱选择性微电极技术,观察到小剂量赛拉嗪(2.0和6.0mg·kg^-1)可显著增加大鼠海马CA1区ACh的含量,而大剂量赛拉嗪(10.0mg·kg^-1)及咪唑克生(0.6mg·kg^-1)则作用相反。咪唑克生虽可明显拮抗赛拉嗪的作用,但海马CA₁区ACh的含量仍显著低于正常水平。在去兰斑核的大鼠上,赛拉嗪(2.0和6.0mg·kg^-1)及咪唑克生(0.6mg·kg^-1)分别对海马CA₁区ACh的含量具有减少和增加作用,且咪唑克生拮抗赛拉嗪的作用后,海马CA₁区ACh的含量基本恢复至正常水平。结果提示,赛拉嗪对麻醉大鼠海马CA₁区ACh含量呈双相性影响,咪唑可生虽能显著拮抗赛拉嗪的作用,但海马CA₁区ACh的含量仍明显低于正常水平,可能分别与赛拉嗪和咪唑克生降低或提高中枢NE能系统的功能有关。     

Observations of vitamin A toxicity in three patients with renal failure receiving parenteral alimentation

Elevated serum retinol concentrations have been previously reported in patients with renal failure, although overt clinical toxicity has been described only rarely. We present three patients with renal failure receiving total parenteral nutrition (TPN) who developed biochemical and clinical findings of hypervitaminosis A. Improvement followed deletion of vitamin A from the TPN. These cases demonstrate that patients with renal failure may be at risk for symptomatic vitamin A toxicity if given TPN with standard retinol supplementation. Such patients should be carefully observed clinically and biochemically if supplementation is given.     

A PIL for every ill? Patient information leaflets (PILs): a review of past, present and future use

This article reviews the usefulness and importance of written information, specifically leaflets, being given to patients. Evidence suggesting how both patient and doctor may benefit from the giving of written information is reviewed. Identification of good practice relating to the content and readability of leaflets is discussed. An argument is put forward that the giving of written information is an under-utilized resource in contributing to improving patient outcomes but that this may be changing with the increasing use of patient leaflet databases. The advantages and disadvantages of computer- generated patient leaflets are discussed and desirable further areas of research on computer-generated leaflets are proposed.      

Neonatal treatment with 192 IgG-saporin produces long-term forebrain cholinergic deficits and reduces dendritic branching and spine density of neocortical pyramidal neurons

The role of basal forebrain-derived cholinergic afferents in the development of neocortex was studied in postnatal rats. Newborn rat pups received intraventricular injections of 192 IgG-saporin. Following survival periods ranging from 2 days to 6 months, the brains were processed to document the cholinergic lesion and to examine morphological consequences. Immunocytochemistry for choline acetyltransferase (ChAT) and in situ hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the cholinergic neurons in the medial septum and nucleus of the diagonal band of Broca in the basal forebrain. In situ hybridization for glutamic acid decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons. Acetylcholinesterase histochemistry demonstrates a marked reduction of the cholinergic axons in neocortex. Cholinergic axons are reduced throughout the cortical layers; this reduction is more marked in medial than in lateral cortical areas. The thickness of neocortex is reduced by approximately 10%. Retrograde labeling of layer V cortico-collicular pyramidal cells reveals a reduction in cell body size and also a reduction in numbers of branches of apical dendrites. Spine densities on apical dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated cases; no change was detected in number of spines on basal dendrites. These results indicate a developmental or maintenance role for cholinergic afferents to cerebral cortical neurons.      

共轭方向法在HPLC流动相条件优化中的应用——麻黄碱、伪麻黄碱的分离

麻黄碱与伪麻黄碱是中药麻黄的主要有效成分,也是一对化学物理性质很相似的差向异构体。二者的结构只是构象不同,用色谱方法进行分离有一定的难度。目前已有在苯基和腈基键合固定相上进行HPLC分离的报道^(1,2)。本文成功地引入共轭方向法在μBondapak C₁₈色谱柱上对流动相组成进行了条件优化,优化后的色谱条件下麻黄碱与伪麻黄碱的分离情况令人满意。