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1.

Background

In the past twenty years, codeine-containing cough syrups (CCS) was recognized as a new type of addictive drugs. However, the exact neurobiologic mechanisms underlying CCS-dependence are still ill-defined. The aims of this study are to identify CCS-related modulations of neural activity during the resting-state in CCS-dependent individuals and to investigate whether these changes of neural activity can be related to duration of CCS use, the first age of CCS use and impulse control deficits in CCS-dependent individuals. We also want to observe the impact of gray matter deficits on these functional results.

Methodology/Principal Findings

Thirty CCS-dependent individuals and 30 control subjects participated. Resting-state functional MRI was performed by using gradient-echo echo-planar imaging sequence. Regional homogeneity (ReHo) was calculated by using REST software. Voxel-based analysis of the ReHo maps between controls and CCS-dependent groups was performed using two-sample t tests (p<0.05, corrected for multiple comparisons). The Barratt Impulsiveness Scale 11 (BIS.11) was surveyed to assess participants'' impulsivity trait soon after MR examination. Abnormal clusters revealed by group comparison were extracted and correlated with impulsivity, duration of CCS use, and age of first CCS use. ReHo was diminished in the bilateral medial orbitofrontal cortex (mOFC) and left dorsal striatum in CCS-dependent individuals. There were negative correlations between mean ReHo in the bilateral medial OFC, left dorsal striatum and duration of CCS use, BIS.11 total scores, and the subscale of attentional impulsivity in CCS-dependent individuals. There was a significantly positive correlation between mean ReHo in the left dorsal striatum and age of first CCS use in CCS-dependent individuals. Importantly, these results still remain significant after statistically controlling for the regional gray matter deficits.

Conclusion

Resting-state abnormalities in CCS-dependent individuals revealed in the present study may further improve our understanding about the neural substrates of impulse control dysfunction in CCS-dependent individuals.  相似文献   
2.
In this study, a lab-scale anaerobic/anoxic/zeolite biofilter-membrane bioreactor (A1/A2/ZB-MBR) was designed to treat coking wastewater. The 454 pyrosequencing was used to obtain the composition and dynamics of microbial community about the treatment system. The results showed that the system yielded stable effluent chemical oxidation demand (158.5?±?21.8 mg/L) and ammonia (8.56?±?7.30 mg/L), but fluctuant total nitrogen (31.4–165.1 mg/L) concentrations. In addition, 66,256 16S rRNA gene sequences were obtained from A2 and ZB-MBR, and the microbial diversity and richness for five samples were determined. Although community compositions in the five samples were quite different, bacteria assigned to phylum Proteobacteria and class Flavobacteria commonly existed and dominated the microbial populations. The pyrosequencing analysis revealed that the microbial community shifted in the ZB-MBR with the presence of zeolite. Some taxa began to appear in ZB-MBR and contributed to the system performance. Additionally, Nitrosomonas and Nitrobacter gradually became the dominant ammonia-oxidizing bacteria and nitrite-oxidizing bacteria during the operation, respectively, which are favorable for the stabilized ammonia removal. Our results proved that the ZB-MBR is an alternative technique for treating coking wastewater.  相似文献   
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细胞因子可介导许多生物学过程并受到机体的严格调节,其调节的失控可引发一系列疾病如自身免疫炎症和肿瘤。在过去的十几年中,一些能够有效调节细胞因子生物学作用的生物制剂如重组抗炎细胞因子、细胞因子受体以及中和性抗体等被广泛应用到由细胞因子失调引起的相关疾病的治疗。尤其是近年来,一些具有创新性的靶向细胞因子的新型生物制剂在不断涌现。文中对近年来国际上靶向炎症细胞因子(TNF-α、IL-1β、IL-6、IL-17)的生物制剂的研发和临床应用的相关进展进行了综述,指出其副作用和应用风险,并结合其他学者和自己的研究工作提出减少副作用和风险的途径和方法。利用现代生物技术提高抗细胞因子生物制剂针对炎症或肿瘤组织的特异性,是靶向炎性细胞因子生物制剂未来的重要发展方向。  相似文献   
5.
Zhao L  Wang L  Ji W  Wang X  Zhu X  Feng Q  Yang W  Yin W 《Cytokine》2007,37(1):71-75
Angiotensin-converting enzyme (ACE) plays an important role in pulmonary fibrosis and may be involved in the development of radiation-induced lung damage. The objective of this study was to evaluate the predictive value of plasma ACE in radiation pneumonitis (RP). Patients with stage I-III lung cancer were treated with radiotherapy with or without chemotherapy. ACE levels were measured using enzyme-linked immunosorbent assay before radiotherapy (pre-RT) and when a median dose of 45 Gy (Range: 40-48 Gy) was reached (during-RT). The primary end point was > or = grade 2 RP. Statistic significances were evaluated with independent T-test and chi-square. Thirty-nine patients were enrolled in this study, among which 33.3% experienced > or = grade 2 RP. ACE levels, either pre-RT or during-RT, were significantly lower in the RP group than in the non-RP group (P=0.02 and 0.03, respectively). Nine out of the 19 patients (47.4%) with pre-RT ACE levels < or = 462 ng/mL experienced RP, versus 3 of 19 (15.8%) patients with ACE levels > 462 ng/mL (P=0.04). This study suggested that plasma ACE as a predictive factor for radiation pneumonitis deserves further study.  相似文献   
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Hepatic stellate cells (HSCs) are important part of the local 'stem cell niche' for hepatic progenitor cells (HPCs) and hepatocytes. However, it is unclear as to whether the products of activated HSCs are required to attenuate hepatocyte injury, enhance liver regeneration, or both. In this study, we performed 'loss of function' studies by depleting activated HSCs with gliotoxin. It was demonstrated that a significantly severe liver damage and declined survival rate were correlated with depletion of activated HSCs. Furthermore, diminishing HSC activation resulted in a 3-fold increase in hepatocyte apoptosis and a 66% decrease in the number of proliferating hepatocytes. This was accompanied by a dramatic decrease in the expression levels of five genes known to be up-regulated during hepatocyte replication. In particular, it was found that depletion of activated HSCs inhibited oval cell reaction that was confirmed by decreased numbers of Pank-positive cells around the portal tracts and lowered gene expression level of cytokeratin 19 (CK19) in gliotoxin-treated liver. These data provide clear evidence that the activated HSCs are involved in both hepatocyte death and proliferation of hepatocytes and HPCs in acetaminophen (APAP)-induced acute liver injury.  相似文献   
8.
The success of hepatocellular therapies using stem or progenitor cell populations is dependent upon multiple factors including the donor cell, microenvironment, and etiology of the liver injury. The following experiments investigated the impact of TGF-beta1 on a previously described population of hepatic progenitor cells (HPC). The majority of the hepatic progenitor cells were resistant to endogenously produced TGF-beta1's proapoptotic and anti-proliferative effects unlike more well-differentiated cellular populations (e.g., mature hepatocytes). Surprisingly, in vitro TGF-beta1 supplementation significantly inhibited de novo hepatic progenitor cell colony formation possibly via an indirect mechanism(s). Therefore despite the HPC's direct resistance to supplemental TGF-beta1, this cytokine's inhibitory effect on colony formation could have a potential negative impact on the use of these cells as a therapy for patients with liver disease.  相似文献   
9.
骨髓基质干细胞向心肌细胞诱导分化的实验研究   总被引:1,自引:0,他引:1  
目的探讨大鼠骨髓基质干细胞在体外和体内向心肌细胞诱导分化的能力,为下一步的细胞移植治疗心肌梗死提供实验基础.方法体外诱导实验中,将不同浓度的5-氮胞苷作用于不同培养时间的骨髓基质干细胞,摸索5-氮胞苷的最佳诱导时机和浓度,观察诱导后细胞形态变化,并用免疫细胞化学染色检测心肌特异性肌钙蛋白T的表达;在体内实验中,培养扩增的骨髓基质干细胞经BrdU标记后,自体移植于正常心肌内,分别通过BrdU和心肌特异性肌钙蛋白T免疫组织化学染色检测移植细胞的存活和分化情况.结果体外诱导实验中,5-氮胞苷的诱导作用以10μmol/L的浓度对传代细胞进行两次诱导,效果最好,不仅能诱导出表达心肌特异蛋白的心肌样细胞,而且这些细胞在体外能够自发搏动.体内诱导实验中,移植的细胞在正常心肌微环境中能够存活并分化为心肌细胞.结论骨髓基质干细胞在体外化学诱导和体内心肌微环境诱导时均能分化为心肌细胞,可用于细胞移植治疗心肌梗死的实验.  相似文献   
10.
为探明长期施肥与土壤动物群落之间的关系,于2001年6月至2002年10月,在陕西黄土区对不同施肥条件下的农田土壤动物类群的群落组成和结构进行了研究.在6种不同施肥处理的小区内,即对照组(不施肥,简称CK)、撂荒(不施肥、不耕作、不种植,简称ABAND)、施氮磷钾(简称NPK)、施氮磷钾+秸秆(简称SNPK)、施氮磷钾+有机肥(简称MNPK)和施1.5倍MNPK(简称1.5MNPK),两年4次共采集了72个定点土壤样品.采用手捡法和Cobb过筛法共获得农田土壤动物标本5495个,隶属6门11纲22目61科2亚科35属.结果显示6种施肥处理中,大型农田土壤动物的个体总数从多到少依次为SNPK>1.5MNPK>NPK>ABAND>MNPK>CK,类群数依次是1.5MNPK>NPK>SNPK>CK>ABAND=MNPK.中小型农田土壤动物个体总数由多到少依次为1.5MNPK>MNPK>ABAND>SNPK>NPK>CK,类群数依次是SNPK=MNPK>CK=NPK=1.5MNPK>ABAND.大型农田土壤动物个体数和类群数分布最多的分别是SNPK和1.5MNPK处理,而中小型农田土壤动物则分别是1.5MNPK和SNPK处理.表明农田土壤动物类群分布与施肥处理有关.农田土壤动物优势类群分布以施氮磷钾(NPK)小区最多,常见类群以对照组(CK)最多,极稀有类群以施1.5倍MNPK小区最多.群落相似性指数分析结果表明,在不同施肥处理之间,农田土壤动物的相似性系数一般较低,而其群落组成的异质性较高如大型土壤动物群落在撂荒地与其他施肥处理之间的相似性明显低于其他各施肥处理之间;而中小型土壤动物群落在对照小区与其他施肥之间的相似性指数明显低于其他各施肥处理之间,反映出不同施肥处理对土壤生态系统内部环境,进而对土壤动物群落产生的影响.  相似文献   
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