BACKGROUND & AIMS: The attachment protein or G protein of the A2 strain of human respiratory syncytial virus (RSV) was digested with trypsin and the resultant peptides separated by reverse-phase high-performance liquid chromatography (HPLC). One tryptic peptide produced a mass by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) corresponding to residues 152-187 with the four Cys residues of the ectodomain (residues 173, 176, 182, and 186) in disulfide linkage and absence of glycosylation. Sub-digestion of this tryptic peptide with pepsin and thermolysin produced peptides consistent with disulfide bonds between Cys173 and Cys186 and between Cys176 and Cys182. Analysis of ions produced by post-source decay of a peptic peptide during MALDI-TOF-MS revealed fragmentation of peptide bonds with minimal fission of an inter-chain disulfide bond. Ions produced by this unprecedented MALDI-induced post-source fragmentation corroborated the existence of the disulfide arrangement deduced from mass analysis of proteolysis products. These findings indicate that the ectodomain of the G protein has a non-glycosylated subdomain containing a "cystine noose."

背景与目标： 用胰蛋白酶消化人呼吸道合胞病毒 (RSV) 的A2菌株的附着蛋白或g蛋白，并通过反相高效液相色谱 (HPLC) 分离所得肽。一种胰蛋白酶肽通过基质辅助激光解吸/电离 (MALDI) 飞行时间 (TOF) 质谱 (MS) 产生了与胞外域的四个Cys残基152-187的残基 (残基173，176，182，和186) 在二硫键连接和不存在糖基化。用胃蛋白酶和嗜热菌素对这种胰蛋白酶进行亚消化，产生的肽与Cys173和Cys186之间以及Cys176和cys182之间的二硫键一致。对maldi-tof-MS期间消化肽的源后衰变产生的离子的分析表明，肽键断裂，链间二硫键的裂变最小。这种前所未有的MALDI诱导的后源断裂产生的离子证实了从蛋白水解产物的质量分析得出的二硫键排列的存在。这些发现表明g蛋白的外结构域具有包含 “胱氨酸套索” 的非糖基化亚域。

BACKGROUND & AIMS: PURPOSE:Panax notoginseng is a commonly used Chinese herb. Although a few studies have found that notoginseng shows anti-tumor effects, the effect of this herb on colorectal cancer cells has not been investigated. 5-Fluorouracil (5-FU) is a chemotherapeutic agent for the treatment of colorectal cancer that interferes with the growth of cancer cells. However, this compound has serious side effects at high doses. In this study, using HCT-116 human colorectal cancer cell line, we investigated the possible synergistic anti-cancer effects between notoginseng flower extract (NGF) and 5-FU on colon cancer cells. METHODS:The anti-proliferation activity of these modes of treatment was evaluated by MTS cell proliferation assay. Apoptotic effects were analyzed by using Hoechst 33258 staining and Annexin-V/PI staining assays. The anti-proliferation effects of four major single compounds from NGF, ginsenosides Rb1, Rb3, Rc and Rg3 were also analyzed. RESULTS:Both 5-FU and NGF inhibited proliferation of HCT-116 cells. With increasing doses of 5-FU, the anti-proliferation effect was slowly increased. The combined usage of 5-FU 5 microM and NGF 0.25 mg/ml, significantly increased the anti-proliferation effect (59.4 +/- 3.3%) compared with using the two medicines separately (5-FU 5 microM, 31.1 +/- 0.4%; NGF 0.25 mg/ml, 25.3 +/- 3.6%). Apoptotic analysis showed that at this concentration, 5-FU did not exert an apoptotic effect, while apoptotic cells induced by NGF were observed, suggesting that the anti-proliferation target(s) of NGF may be different from that of 5-FU, which is known to inhibit thymidilate synthase. CONCLUSIONS:This study demonstrates that NGF can enhance the anti-proliferation effect of 5-FU on HCT-116 human colorectal cancer cells and may decrease the dosage of 5-FU needed for colorectal cancer treatment.

背景与目标：

BACKGROUND & AIMS: :Etanercept is a recombinant human soluble tumor necrosis factor (TNF-alpha) receptor fusion protein that inhibits TNF-alpha, a major mediator in the pathogenesis of graft-versus-host disease (GVHD). The purpose of our study was to evaluate the safety and efficacy of etanercept therapy in 21 patients with steroid-refractory acute GVHD (aGVHD) (n = 13) and chronic GVHD (cGVHD) (n = 8). Etanercept 25 mg was given subcutaneously twice weekly for 4 weeks followed by 25 mg weekly for 4 weeks. At the time of initiation of etanercept, 14 patients had skin, 13 had gastro-intestinal, 5 had liver, 5 had pulmonary, and 4 had oral involvement. Twelve patients (57%) completed 12 doses of therapy. Overall, 11 of 21 patients (52%) responded to the treatment with etanercept, including 6 patients (46%) with aGVHD [n = 4 complete response (CR), n = 2 partial response (PR)] and 5 patients (62%) with cGVHD (n = 1 CR, n = 4 PR). Clinical responses were most commonly seen in patients with refractory gut aGVHD with 55% of the patients having a CR and 9% having a PR. CMV reactivation occurred in 48% of patients, bacterial infections in 14% of patients, and fungal infections in 19% of patients. Fourteen patients (67%) were alive after a median follow-up of 429 days (range 71-1007 days) since initiation of etanercept. Seven patients died, 3 of infections, 2 of refractory aGVHD, and 2 of disease progression. In conclusion, our preliminary data indicate that etanercept is well tolerated and can induce a high response rate in patients with steroid-refractory aGVHD and cGVHD, particularly in the setting of GI involvement.

背景与目标： : 依那西普是一种重组人可溶性肿瘤坏死因子 (TNF-α) 受体融合蛋白，可抑制TNF-α，TNF-α 是移植物抗宿主病 (GVHD) 发病机理中的主要介质。我们研究的目的是评估依那西普治疗21例类固醇难治性急性GVHD (aGVHD) (n = 13) 和慢性GVHD (cGVHD) (n = 8) 患者的安全性和有效性。依那西普25 mg，每周皮下注射两次，持续4周，然后每周注射25 mg，持续4周。在开始使用依那西普时，14例患者有皮肤，13例有胃肠道，5例有肝脏，5例有肺部，4例有口腔受累。12名患者 (57%) 完成12剂治疗。总体而言，21例患者中有11例 (52%) 对依那西普治疗有反应，其中6例 (46% 例) aGVHD [n = 4完全缓解 (CR)，n = 2部分缓解 (PR)] 和5例 (62%) cGVHD (n = 1 CR，n = 4 PR)。临床反应最常见于难治性肠道aGVHD患者，其中55% 患者具有CR，9% 患者具有PR。48% 患者发生CMV再激活，14% 患者发生细菌感染，19% 患者发生真菌感染。自依那西普开始以来，中位随访429天 (范围71-1007天) 后，有14名患者 (67%) 还活着。7例患者死亡，3例感染，2例难治性aGVHD，2例疾病进展。总之，我们的初步数据表明，依那西普具有良好的耐受性，并且可以在类固醇难治性aGVHD和cGVHD患者中诱导高反应率，尤其是在GI受累的情况下。

BACKGROUND & AIMS: :Finding work and/or re-entering the workforce can be extremely challenging for persons living with HIV/AIDS. Also difficult is assisting them in the process, mostly because there is little documentation or resources about programs that provide vocational services specifically for this population. In response to this dilemma and because it was perceived as a win/win situation, three urban residential community organizations serving the HIV/AIDS population, decided independently to create in-house work opportunities for their clients. All of these organizations are a variation of the same theme: transitional/supportive housing for persons with HIV/AIDS that were formerly homeless and are now interested in becoming increasingly self-sufficient. This article will present a program description that addresses unique manner in which these three sites created in-house job programs in the areas of receptionist, kitchen, and maintenance work. More specifically, this paper will address the strengths, limitations, and ethical considerations that guided program development.

背景与目标： : 对于艾滋病毒/艾滋病感染者来说，找到工作和/或重新进入劳动力队伍可能极具挑战性。协助他们的过程也很困难，主要是因为关于专门为该人群提供职业服务的计划的文档或资源很少。为了应对这一困境，并因为这被认为是双赢的局面，为艾滋病毒/艾滋病人口服务的三个城市居民社区组织独立决定为其客户创造内部工作机会。所有这些组织都是同一主题的变体: 为以前无家可归的艾滋病毒/艾滋病患者提供过渡/支持性住房，现在对变得越来越自给自足感兴趣。本文将介绍一个程序描述，该程序描述了这三个站点在接待员，厨房和维护工作领域创建内部工作程序的独特方式。更具体地说，本文将讨论指导计划开发的优势，局限性和道德考虑因素。

BACKGROUND & AIMS: :The prevalence of IgG antibodies against Mycobacterium leprae recombinant culture filtrate protein-10 (rCFP-10) was investigated in serum samples from 56 leprosy patients, 15 tuberculosis (TB) patients, 14 other skin-diseased patients and 20 healthy subjects. On classifying the patients into bacterial index (BI)-positive and BI-negative groups, the assay showed 83.3 % (15/18) sensitivity for detection of BI-positive leprosy patients. On the other hand, the sensitivity for detection of BI-negative patients was 18.4 % (7/38). None of the 15 TB patients and 14 other skin-diseased patients was positive; however, only one out of 20 healthy individuals was positive, indicating that antibody response to culture filtrate protein-10 (CFP-10) was highly specific (98.0 %; 48/49). Statistically, the performance of the CFP-10-based assay was found to be comparable (P>0.05) with that of an anti-phenolic glycolipid-I (PGL-I) antibody-detecting assay. Thus, M. leprae CFP-10 is potentially a specific antigen for measuring antibody response in BI-positive leprosy patients. Being a secreted antigen, CFP-10 may act as a marker for the viability of M. leprae inside the host, and hence its serological potential is worth exploring for application in monitoring the response of patients with BI-positive leprosy (a highly infectious form) during the course of chemotherapy. When comparing the bacteriological and serological results, an agreement of 82.1 % showed that seropositivity to M. leprae CFP-10 corresponded well with bacteriological criteria. Hence, CFP-10 seems to be a suitable antigen for classification of leprosy patients into BI-positive and BI-negative groups.

背景与目标： : 在56名麻风病患者，15名结核病 (TB) 患者，14名其他皮肤病患者和20名健康受试者的血清样本中，研究了针对麻风分枝杆菌重组培养滤液蛋白10 (rCFP-10) 的IgG抗体的患病率。在将患者分为细菌指数 (BI) 阳性和BI阴性组时，该测定显示了检测BI阳性麻风病患者的83.3% (15/18) 敏感性。另一方面，检测双阴性患者的灵敏度18.4% (7/38)。15个TB患者和14个其他皮肤疾病患者中没有一个是阳性的; 然而，20个健康个体中只有一个是阳性的，表明对培养滤液蛋白10 (CFP-10) 的抗体反应是高度特异性的 (98.0%; 48/49)。统计学上，发现CFP-10-based测定的性能与抗-酚糖脂-I (pgl-i) 抗体检测测定的性能相当 (P>0.05)。因此，麻风分枝杆菌CFP-10潜在地是用于测量双阳性麻风病患者的抗体应答的特异性抗原。作为一种分泌的抗原，CFP-10可以作为宿主内麻风支原体生存能力的标志物，因此其血清学潜力值得探索，用于监测双阳性麻风病 (一种高度感染形式) 患者在化疗过程中的反应。当比较细菌学和血清学结果时，82.1% 的一致性表明麻风分枝杆菌的血清阳性CFP-10与细菌学标准非常吻合。因此，CFP-10似乎是用于将麻风病患者分为双阳性和双阴性组的合适抗原。

BACKGROUND & AIMS: :Iminodisuccinate (IDS) epimerase catalyzes the epimerisation of R,R-, S,S- and R,S- iminodisuccinate, one step in the biodegradation of the chelating agent iminodisuccinate by Agrobacterium tumefaciens BY6. The enzyme is a member of the MmgE/PrpD protein family, a diverse and little characterized class of proteins of prokaryotic and eukaryotic origin. IDS epimerase does not show significant overall amino acid sequence similarity to any other protein of known three-dimensional structure. The crystal structure of this novel epimerase has been determined by multi-wavelength diffraction to 1.5 A resolution using selenomethionine-substituted enzyme. In the crystal, the enzyme forms a homo-dimer, and the subunit consists of two domains. The larger domain, not consecutive in sequence and comprising residues Met1-Lys266 and Leu400-Pro446, forms a novel all alpha-helical fold with a central six-helical bundle. The second, smaller domain folds into an alpha+beta domain, related in topology to chorismate mutase by a circular permutation. IDS epimerase is thus not related in three-dimensional structure to other known epimerases. The fold of the IDS epimerase is representative for the whole MmgE/PrpD family. The putative active site is located at the interface between the two domains of the subunit, and is characterized by a positively charged surface, consistent with the binding of a highly negatively charged substrate such as iminodisuccinate. Docking experiments suggest a two-base mechanism for the epimerisation reaction.

背景与目标： : 亚氨基二琥珀酸酯 (IDS) 差向异构化催化R，R-，S，S-和R，S-亚氨基二琥珀酸酯的差向异构化，这是根癌农杆菌对螯合剂亚氨基二琥珀酸酯生物降解的第一步。该酶是MmgE/PrpD蛋白家族的成员，MmgE/PrpD蛋白家族是原核和真核来源的多种多样且特征很少的蛋白质。IDS差向异构酶与已知三维结构的任何其他蛋白质没有显示出明显的总体氨基酸序列相似性。该新型差向异构酶的晶体结构已通过多波长衍射确定，以使用硒代蛋氨酸取代的酶1.5分辨率。在晶体中，酶形成同型二聚体，亚基由两个结构域组成。较大的结构域不是连续的并且包含Met1-Lys266和Leu400-Pro446的残基，形成具有中心六螺旋束的新型全 α-螺旋折叠。第二个较小的结构域折叠成 α β 结构域，在拓扑上通过环状排列与脉络酸突变酶有关。因此，IDS差向异构酶在三维结构上与其他已知的差向异构酶无关。IDS差向异构酶的折叠代表整个MmgE/PrpD家族。推定的活性位点位于亚基的两个结构域之间的界面处，其特征在于带正电的表面，与高度带负电的底物 (例如亚氨基二琥珀酸酯) 的结合一致。对接实验提出了向异构化反应的两基机制。

BACKGROUND & AIMS: BACKGROUND:This study was undertaken to obtain differentially expressed genes related to human glioma by cDNA microarray and the characterization of a novel full-length gene. METHODS:Total RNA was extracted form human glioma and normal brain tissue, and mRNA was used as a probe. The results of hybridization procedure were scanned with the computer system. The gene named 507E08 cone was subsequently analyzed by northern blot, bioinformatic approach, and protein expression. RESULTS:Fifteen differentially expressed genes were obtained from human glioma by hybridization and scanning for four times. Northern blot analysis confirmed that the 507E08 clone was low expressed in human brain tissue and over expressed in human glioma tissues. The analysis of BLASTn and BLASTx showed that the 507E08 clone was a novel full-length gene, which codes 203 amino acid of protein and is called human ribosomal protein 14.22 gene. The nucleotide sequence had been submitted to the GenBank with the accession number of AF329277. After expression in E. coli., protein yielded a major band of apparent molecular mass 22 kDa on an SDS-PAGE gel. CONCLUSIONS:cDNA microarray technology can be successfully used to identify differentially expressed genes. The novel full-length gene of human ribosomal protein 13.22 may be correlated with the development of human glioma.

背景与目标：

BACKGROUND & AIMS: Malnutrition is a common complication of HIV infection and plays a significant and independent role in morbidity and mortality. Many studies have been conducted to assess the appropriate role of nutrition in the clinical management of HIV infection. The complex nature of AIDS wasting, however, requires individualized strategies when providing nutritional support. Algorithms to assist in the diagnosis and treatment of malnutrition in HIV infection serve as general guidelines.

背景与目标： 营养不良是HIV感染的常见并发症，在发病率和死亡率中起着重要而独立的作用。已经进行了许多研究，以评估营养在HIV感染的临床管理中的适当作用。然而，艾滋病浪费的复杂性要求在提供营养支持时采取个性化策略。协助诊断和治疗HIV感染中营养不良的算法是一般指南。

BACKGROUND & AIMS: There is evidence that neutrophil functions such as chemotaxis and oxygen radical formation are disturbed in rheumatoid arthritis (RA). Medication might also influence these functions. Cyclic formation and depolymerisation of actin microfilaments is crucial in cell motility, but this phenomenon has not been studied in RA. The aim of this study was to investigate basal and dynamic (formyl-methionyl-leucyl-phenylalanine (fMLP)-induced) neutrophil actin polymerisation in ten RA patients (a) during therapy with non-steroidal anti-inflammatory drugs (NSAIDS) and (b) after stopping NSAIDS> The results were compared with those of ten age-matched controls. Basal F-actin content in RA patients with NSAIDS was significantly lower than in RA patients without NSAIDS and controls35.5 (25.0-49.0), 50.5 (27.0-75.0) and 52.5 (32.0-85.0), respectively. Conversely, upon stimulation with fMLP, the actin polymerisation curve of RA patients with NSAIDS was higher than for RA patients without NSAIDS and controls. These results suggest that, in RA, the effects orf NSAIDS on neutrophil functions might be related to changes in the actin polymerisation-depolymerisation cycle.

背景与目标： 有证据表明，类风湿性关节炎 (RA) 的中性粒细胞功能 (例如趋化性和氧自由基形成) 受到干扰。药物也可能影响这些功能。肌动蛋白微丝的循环形成和解聚对细胞运动至关重要，但尚未在RA中研究这种现象。这项研究的目的是研究10名RA患者 (a) 在非甾体类抗炎药 (nsaid) 治疗期间的基础和动态 (甲酰基-甲硫氨酸-亮氨酸-苯丙氨酸 (fMLP) 诱导的) 中性粒细胞肌动蛋白聚合反应 (a) 和 (b) 停止nsaid后的结果进行比较有十个年龄匹配的对照。患有NSAIDS的RA患者的基础F-肌动蛋白含量显着低于没有NSAIDS和对照组的RA患者35.5 (25.0-49.0)，50.5 (27.0-75.0) 和52.5 (32.0-85.0)。相反，用fMLP刺激后，患有NSAIDS的RA患者的肌动蛋白聚合曲线高于没有NSAIDS的RA患者和对照组。这些结果表明，在RA中，orf nsaid对中性粒细胞功能的影响可能与肌动蛋白聚合-解聚周期的变化有关。

BACKGROUND & AIMS: :Few details are known about how the human immunodeficiency virus type 1 (HIV-1) genomic RNA is trafficked in the cytoplasm. Part of this process is controlled by the activity of heterogeneous nuclear ribonucleoprotein A2 (hnRNP A2). The role of hnRNP A2 during the expression of a bona fide provirus in HeLa cells is investigated in this study. Using immunofluorescence and fluorescence in situ hybridization techniques, we show that knockdown of hnRNP A2 expression in HIV-1-expressing cells results in the rapid accumulation of HIV-1 genomic RNA in a distinct, cytoplasmic space that corresponds to the microtubule-organizing center (MTOC). The RNA exits in the nucleus and accumulates at the MTOC region as a result of hnRNP A2 knockdown even during the expression of a provirus harboring mutations in the hnRNP A2-response element (A2RE), the expression of which results in nuclear retention of genomic RNA. We also demonstrate that hnRNP A2 expression is required for downstream trafficking of genomic RNA from the MTOC in the cytoplasm. Genomic RNA localization at the MTOC that was both the result of hnRNP A2 knockdown and the overexpression of Rab7-interacting lysosomal protein had little effect on pr55Gag synthesis but negatively influenced virus production and infectivity. These data indicate that altered HIV-1 genomic RNA localization modulates viral assembly and that the MTOC serves as a central site to which HIV-1 genomic RNA converges following its exit from the nucleus, with the host protein, hnRNP A2, playing a central role in taking it to and from this site in the cell.

背景与目标： : 关于人类免疫缺陷病毒1型 (HIV-1) 基因组RNA如何在细胞质中运输的细节知之甚少。该过程的一部分受异质核核糖核蛋白A2 (hnRNP A2) 的活性控制。本研究研究了hnRNP A2在HeLa细胞中真正的前病毒表达中的作用。使用免疫荧光和荧光原位杂交技术，我们显示了HIV-1-expressing细胞中hnRNP A2表达的敲低导致HIV-1基因组RNA在与微管组织中心 (MTOC) 相对应的独特细胞质空间中快速积累。即使在hnRNP A2-response元件 (A2RE) 中携带突变的前病毒的表达过程中，由于hnRNP A2敲除，RNA也会在细胞核中离开并在MTOC区域积累，其表达导致基因组RNA的核保留。我们还证明hnRNP A2表达是细胞质中来自MTOC的基因组RNA下游运输所必需的。hnRNP A2敲低的结果和Rab7-interacting溶酶体蛋白的过表达在MTOC上的基因组RNA定位对pr55Gag的合成几乎没有影响，但对病毒的产生和感染性产生负面影响。这些数据表明，改变的HIV-1基因组RNA定位调节病毒组装，并且MTOC充当HIV-1基因组RNA从细胞核退出后会聚的中心位点，宿主蛋白hnrnpa2在将其带到和从细胞中的该位点中起着核心作用。

BACKGROUND & AIMS: We studied changes in glutamate receptors, expression of immediate early genes, and AP-1 DNA binding activity in the brains of phenobarbital (PB)-dependent and -withdrawn rats to investigate the possible involvement of activation of glutamate receptors in PB withdrawal syndrome. PB-dependent rats were prepared by feeding drug-admixed food for 5 weeks. Autoradiographic analysis showed that binding of [3H(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imin e (MK-801), an antagonist of N-methyl-D-aspartic acid (NMDA) receptors, increased significantly in the cerebral cortices of PB-dependent and 24-h-withdrawn rats. However, [3H]MK-801 binding in the hippocampus and [3H]6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and [3H]kainic acid binding in the hippocampus and cerebral cortex were essentially unchanged in both groups. PB withdrawal seizures were followed by increased expression of c-fos mRNA in the hippocampus and cerebral cortex and of c-jun mRNA in the cerebral cortex. The induction of c-fos and c-jun mRNA was suppressed by administration of MK-801. Furthermore, PB withdrawal enhanced AP-1 DNA binding activity in the brain. The present findings suggest functional enhancement of glutamatergic neurotransmission during the development of PB withdrawal syndrome.

背景与目标： 我们研究了苯巴比妥 (PB) 依赖性和退缩大鼠大脑中谷氨酸受体的变化，即刻早期基因的表达以及AP-1的DNA结合活性，以研究谷氨酸受体激活在PB戒断综合征中的可能参与。通过喂养混合药物的食物5周制备PB依赖性大鼠。放射自显影分析显示，N-甲基-d-天冬氨酸 (NMDA) 受体拮抗剂 [3H(+)-5-甲基-10,11-二氢-5H-二苯并 [a，D] cyclohepten-5，10-敏e (MK-801) 的结合，PB依赖性和24h撤回大鼠的大脑皮层显着增加。然而，[3h] MK-801在海马和 [3H]6-氰基-7-硝基喹喔啉-2结合，海马和大脑皮层中的3-二酮 (CNQX) 和 [3H] 海藻酸结合在两组中基本上没有变化。铅戒断发作后，海马和大脑皮层中c-fos mRNA的表达增加，大脑皮层中c-6月mRNA的表达增加。诱导c-MK-801可抑制fos和c-6月mRNA。此外，铅戒断增强了大脑中的AP-1 DNA结合活性。目前的发现表明，在铅戒断综合征的发展过程中，谷氨酸能神经传递的功能增强。

BACKGROUND & AIMS: :The extracellular calcium-sensing receptor (CaR) is usually associated with systemic Ca(2+) homeostasis, but the CaR is also expressed in many other tissues, including pancreatic islets of Langerhans. In the present study, we have used human islets and an insulin-secreting cell line (MIN6) to investigate the effects of CaR activation using the calcimimetic R-568, a CaR agonist that activates the CaR at physiological concentrations of extracellular Ca(2+). CaR activation initiated a marked but transient insulin secretory response from both human islets and MIN6 cells at a sub-stimulatory concentration of glucose, and further enhanced glucose-induced insulin secretion. CaR-induced insulin secretion was reduced by inhibitors of phospholipase C or calcium-calmodulin-dependent kinases, but not by a protein kinase C inhibitor. CaR activation was also associated with an activation of p42/44 mitogen-activated protein kinases (MAPK), and CaR-induced insulin secretion was reduced by an inhibitor of p42/44 MAPK activation. We suggest that the beta-cell CaR is activated by divalent cations co-released with insulin, and that this may be an important mechanism of intra-islet communication between beta-cells.

背景与目标： : 细胞外钙感应受体 (CaR) 通常与全身Ca(2) 稳态有关，但CaR也在许多其他组织中表达，包括朗格汉斯的胰岛。在本研究中，我们使用人类胰岛和胰岛素分泌细胞系 (MIN6) 来研究使用钙拟R-568 (一种在细胞外Ca(2) 的生理浓度下激活CaR的CaR激动剂) 激活CaR的作用。CaR激活在葡萄糖的亚刺激浓度下启动了人类胰岛和MIN6细胞的显着但短暂的胰岛素分泌反应，并进一步增强了葡萄糖诱导的胰岛素分泌。磷脂酶C或钙-钙调蛋白依赖性激酶的抑制剂可减少CaR诱导的胰岛素分泌，但蛋白激酶C抑制剂不能减少。CaR激活也与p42/44丝裂原活化蛋白激酶 (MAPK) 的激活有关，并且CaR诱导的胰岛素分泌被p42/44 MAPK激活的抑制剂减少。我们建议 β 细胞CaR被与胰岛素共同释放的二价阳离子激活，这可能是 β 细胞之间胰岛内通讯的重要机制。

BACKGROUND & AIMS: :Biological mineralization of tissues in living organisms relies on proteins that preferentially nucleate minerals and control their growth. This process is often referred to as "templating," but this term has become generic, denoting various proposed mineral-organic interactions including both chemical and structural affinities. Here, we present an approach using self-assembled networks of elastin and fibronectin fibers, similar to the extracellular matrix. When induced onto negatively charged sulfonated polystyrene surfaces, these proteins form fiber networks of approximately 10-mum spacing, leaving open regions of disorganized protein between them. We introduce an atomic force microscopy-based technique to measure the elastic modulus of both structured and disorganized protein before and during calcium carbonate mineralization. Mineral-induced thickening and stiffening of the protein fibers during early stages of mineralization is clearly demonstrated, well before discrete mineral crystals are large enough to image by atomic force microscopy. Calcium carbonate stiffens the protein fibers selectively without affecting the regions between them, emphasizing interactions between the mineral and the organized protein fibers. Late-stage observations by optical microscopy and secondary ion mass spectroscopy reveal that Ca is concentrated along the protein fibers and that crystals form preferentially on the fiber crossings. We demonstrate that organized versus unstructured proteins can be assembled mere nanometers apart and probed in identical environments, where mineralization is proved to require the structural organization imposed by fibrillogenesis of the extracellular matrix.

背景与目标： : 生物体组织的生物矿化依赖于优先使矿物质成核并控制其生长的蛋白质。此过程通常称为 “模板”，但该术语已成为通用术语，表示各种拟议的矿物-有机相互作用，包括化学和结构亲和力。在这里，我们提出了一种使用弹性蛋白和纤连蛋白纤维的自组装网络的方法，类似于细胞外基质。当在带负电荷的磺化聚苯乙烯表面上诱导时，这些蛋白质形成约10-mum间距的纤维网络，在它们之间留下无序蛋白质的开放区域。我们介绍了一种基于原子力显微镜的技术，用于在碳酸钙矿化之前和过程中测量结构化和杂乱无章的蛋白质的弹性模量。在矿化的早期阶段，矿物引起的蛋白质纤维的增稠和硬化得到了清楚的证明，早在离散的矿物晶体足够大以通过原子力显微镜成像之前。碳酸钙选择性地使蛋白质纤维变硬，而不会影响它们之间的区域，从而强调了矿物质与有组织的蛋白质纤维之间的相互作用。通过光学显微镜和二次离子质谱进行的后期观察表明，Ca沿蛋白质纤维集中，并且晶体优先在纤维交叉上形成。我们证明，有组织的蛋白质与非结构化的蛋白质可以仅在纳米之间组装并在相同的环境中进行探测，在这种环境中，矿化被证明需要由细胞外基质的原纤维形成所施加的结构组织。

BACKGROUND & AIMS: CD4+ anti-tumor T cells reactive with rat adenocarcinoma 13762 kill tumor in vitro and cause regression of tumor in vivo. The role of various host immune cells in CD4+ T-cell-mediated tumor elimination in vivo was investigated by adoptive transfer of anti-tumor T cell clones to recipients that were selectively depleted of individual immune cell types. By these means, macrophages and NK cells were found to be required for tumor killing. Depletion of host CD4+ T cells, CD8+ T cells, or neutrophils was without effect on tumor elimination by anti-tumor T cells. An essential role for antigen receptor-negative NK cells is likely dependent upon secretion of IFN-gamma from NK cells since treatment of tumor recipients with anti-IFN-gamma antibody prior to adoptive transfer and tumor challenge abrogated T cell killing, resulting in progressive tumor growth. Viability of adenocarcinoma 13762 or anti-tumor T cells was unaffected by treatment with either IFN-gamma or anti-IFN-gamma antibody in vitro, but cell surface MHC class II expression was induced in tumor cells by exposure to IFN-gamma. In addition, tumor cells were isolated from tumor-bearing animals by absorption using anti-MHC class II antibody, demonstrating that 13762 tumor expresses cell surface MHC class II antigens in situ. However, if hosts were depleted of NK cells before tumor challenge, MHC class II+ tumor was not recovered. Collectively these results suggest that adenocarcinoma 13762 is eliminated by MHC class II-restricted CD4+ T cells by direct tumor killing.

背景与目标： 与大鼠腺癌反应的CD4 + 抗肿瘤T细胞13762在体外杀伤肿瘤并在体内引起肿瘤的消退。通过将抗肿瘤T细胞克隆过继转移到选择性耗尽个体免疫细胞类型的受体，研究了各种宿主免疫细胞在体内CD4 T细胞介导的肿瘤消除中的作用。通过这些方法，发现巨噬细胞和NK细胞是杀死肿瘤所必需的。宿主CD4 T细胞，CD8 T细胞或中性粒细胞的耗竭对抗肿瘤T细胞消除肿瘤没有影响。抗原受体阴性NK细胞的重要作用可能取决于NK细胞中IFN-γ 的分泌，因为在过继转移和肿瘤挑战之前用抗IFN-γ 抗体治疗肿瘤接受者消除了T细胞杀伤，导致进行性肿瘤生长。腺癌13762或抗肿瘤T细胞的活力在体外不受IFN-γ 或抗IFN-γ 抗体治疗的影响，但细胞表面mhcii类表达通过暴露于IFN-γ 在肿瘤细胞中诱导。此外，通过使用抗MHC II类抗体吸收从荷瘤动物中分离肿瘤细胞，证明13762肿瘤原位表达细胞表面MHC II类抗原。但是，如果宿主在肿瘤激发之前耗尽了NK细胞，则MHC II类肿瘤将无法恢复。这些结果共同表明，通过直接杀伤肿瘤，MHC II类限制性CD4 T细胞消除了腺癌13762。

BACKGROUND & AIMS: :Detergent-solubilized plasma membrane protein of either adult bovine or calf lens and high-performance liquid chromatography-purified major intrinsic protein (MIP) of the lens were reconstituted into unilamellar vesicles and planar lipid bilayers. Freeze-fracture studies showed that the density of intramembrane particles in the vesicles was proportional to the protein/lipid ratio. At high ratios, these particles crystallized into tetragonal arrays as does MIP in lens fibers. Channels induced by either purified MIP or detergent-solubilized protein had essentially identical properties. The conductance of multichannel membranes was maximal near 0 mV and decreased to 0.49 +/- 0.08 of the maximum value at voltages greater than 80 mV. The dependence of the conductance on voltage was well fit by a two-state Boltzmann distribution. Voltage steps greater than 30 mV elicited an ohmic current step followed by a slow (seconds) biexponential decrease. The amplitudes and time constants depended on the magnitude but not the sign of the voltage. Steps from 100 mV to voltages less than 30 mV caused the channels to open exponentially with a millisecond time constant. Analysis of latency to first closure after a voltage step gave nearly the same time constants as multichannel kinetics. Single-channel conductance is proportional to salt concentration from 0.1 to 1.0 M in KCl. In 0.1M KCl, the channel had two preferred conductance states with amplitudes of 380 and 160 pS, as well as three additional substates. Multi- and single-channel data suggest that the channel has two kinetically important open states. The channel is slightly anion selective. The properties of the channel do not vary appreciably from pH 7.4 to 5.8 or from pCa 7 to 2. We propose that a channel with these properties could contribute to maintenance of lens transparency and fluid balance.

背景与目标： : 成年牛或小牛晶状体的去污剂溶解的质膜蛋白和高效液相色谱纯化的晶状体的主要内在蛋白 (MIP) 重构为单层囊泡和平面脂质双层。冷冻断裂研究表明，囊泡中膜内颗粒的密度与蛋白质/脂质比率成正比。在高比率下，这些颗粒像透镜纤维中的MIP一样结晶成四方阵列。由纯化的MIP或去污剂溶解的蛋白质诱导的通道具有基本相同的特性。多通道膜的电导在0 mV附近最大，并且在大于80 mV的电压下降至最大值的0.49 +/- 0.08。两态玻尔兹曼分布很好地拟合了电导对电压的依赖性。大于30 mV的电压阶跃引起欧姆电流阶跃，随后缓慢 (秒) 双指数下降。振幅和时间常数取决于幅度，而不取决于电压的符号。从100 mV到电压小于30 mV的阶跃导致通道以毫秒时间常数呈指数打开。对电压阶跃后首次闭合的潜伏期进行分析，得出的时间常数与多通道动力学几乎相同。单通道电导与KCl中0.1至1.0 M的盐浓度成正比。在0.1M KCl中，通道具有两个优选的电导状态，其幅度为380和160 pS，以及三个额外的子状态。多通道和单通道数据表明该通道具有两个在动力学上重要的开放状态。通道具有轻微的阴离子选择性。通道的性质在pH 7.4至5.8或pca7至2之间没有明显变化。我们建议具有这些特性的通道可以有助于维持镜片的透明度和流体平衡。