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951.

Background

The aquaporins (AQPs) are a family of 13 small hydrophobic integral transmembrane water channel proteins involved in transcellular and transepithelial water movement, transport of fluid and cell migration.

Scope of the review

This review article summarizes our knowledge concerning the involvement of AQPs in tumor growth, angiogenesis and metastatic process.

Major conclusions

Tumor cells types express AQPs and a positive correlation exists between histological tumor grade and the AQP expression. Moreover, AQPs are involved also in tumor edema formation and angiogenesis in several solid and hematological tumors.

General significance

AQPs inhibition in endothelial and tumor cells might limit tumor growth and spread, suggesting a potential therapeutic use in the treatment of tumors. This article is part of a Special Issue entitled Aquaporins.  相似文献   
952.
Chimeric antigen receptors (CARs), which combine an antibody-derived binding domain (single chain fragment variable) with T-cell-activating signaling domains, have become a promising tool in the adoptive cellular therapy of cancer. Retro- and lenti-viral transductions are currently the standard methods to equip T cells with a CAR; permanent CAR expression, however, harbors several risks like uncontrolled auto-reactivity. Modification of T cells by electroporation with CAR-encoding RNA to achieve transient expression likely circumvents these difficulties. We here present a GMP-compliant protocol to activate and expand T cells for clinical application. The protocol is optimized in particular to produce CAR-modified T cells in clinically sufficient numbers under full GMP-compliance from late-stage cancer patients. This protocol allows the generation of 6.7 × 108 CAR-expressing T cells from one patient leukapheresis. The CAR-engineered T cells produced pro-inflammatory cytokines after stimulation with antigen-bearing tumor cells and lysed tumor cells in an antigen-specific manner. This functional capacity was maintained after cryopreservation. Taken together, we provide a clinically applicable protocol to transiently engineer sufficient numbers of antigen-specific patient T cells for use in adoptive cell therapy of cancer.  相似文献   
953.
The mechanisms of inflammation in acne are currently subject of intense investigation. This study focused on the activation of adaptive and innate immunity in clinically early visible inflamed acne lesions and was performed in two independent patient populations. Biopsies were collected from lesional and non-lesional skin of acne patients. Using Affymetrix Genechips, we observed significant elevation of the signature cytokines of the Th17 lineage in acne lesions compared to non-lesional skin. The increased expression of IL-17 was confirmed at the RNA and also protein level with real-time PCR (RT-PCR) and Luminex technology. Cytokines involved in Th17 lineage differentiation (IL-1β, IL-6, TGF-β, IL23p19) were remarkably induced at the RNA level. In addition, proinflammatory cytokines and chemokines (TNF-α, IL-8, CSF2 and CCL20), Th1 markers (IL12p40, CXCR3, T-bet, IFN-γ), T regulatory cell markers (Foxp3, IL-10, TGF-β) and IL-17 related antimicrobial peptides (S100A7, S100A9, lipocalin, hBD2, hBD3, hCAP18) were induced. Importantly, immunohistochemistry revealed significantly increased numbers of IL-17A positive T cells and CD83 dendritic cells in the acne lesions. In summary our results demonstrate the presence of IL-17A positive T cells and the activation of Th17-related cytokines in acne lesions, indicating that the Th17 pathway is activated and may play a pivotal role in the disease process, possibly offering new targets of therapy.  相似文献   
954.
The African lion has declined to <35,000 individuals occupying 25% of its historic range. The situation is most critical for the geographically isolated populations in West Africa, where the species is considered regionally endangered. Elevating their conservation significance, recent molecular studies establish the genetic distinctiveness of West and Central African lions from other extant African populations. Interventions to save West African lions are urgently required. However formulating effective conservation strategies has been hampered by a lack of data on the species'' current distribution, status, and potential management deficiencies of protected areas (PAs) harboring lions. Our study synthesized available expert opinion and field data to close this knowledge gap, and formulate recommendations for the conservation of West African lions. We undertook lion surveys in 13 large (>500 km2) PAs and compiled evidence of lion presence/absence for a further eight PAs. All PAs were situated within Lion Conservation Units, geographical units designated as priority lion areas by wildlife experts at a regional lion conservation workshop in 2005. Lions were confirmed in only 4 PAs, and our results suggest that only 406 (273–605) lions remain in West Africa, representing <250 mature individuals. Confirmed lion range is estimated at 49,000 km2, or 1.1% of historical range in West Africa. PAs retaining lions were larger than PAs without lions and had significantly higher management budgets. We encourage revision of lion taxonomy, to recognize the genetic distinctiveness of West African lions and highlight their potentially unique conservation value. Further, we call for listing of the lion as critically endangered in West Africa, under criterion C2a(ii) for populations with <250 mature individuals. Finally, considering the relative poverty of lion range states in West Africa, we call for urgent mobilization of investment from the international community to assist range states to increase management effectiveness of PAs retaining lions.  相似文献   
955.
956.

Background and Aims

The virus/host interplay mediates liver pathology in chronic HBV infection. MiRNAs play a pivotal role in virus/host interactions and are detected in both serum and HBsAg-particles, but studies of their dynamics during chronic infection and antiviral therapy are missing. We studied serum miRNAs during different phases of chronic HBV infection and antiviral treatment.

Methods

MiRNAs were profiled by miRCURY-LNA-Universal-RT-miRNA-PCR (Exiqon-A/S) and qPCR-panels-I/II-739-miRNA-assays and single-RT-q-PCRs. Two cohorts of well-characterized HBsAg-carriers were studied (median follow-up 34–52 months): a) training-panel (141 sera) and HBsAg-particles (32 samples) from 61 HBsAg-carriers and b) validation-panel (136 sera) from 84 carriers.

Results

Thirty-one miRNAs were differentially expressed in inactive-carriers (IC) and chronic-hepatitis-B (CHB) with the largest difference for miR-122-5p, miR-99a-5p and miR-192-5p (liver-specific-miRNAs), over-expressed in both sera and HBsAg-particles of CHB (ANOVA/U-test p-values: <0.000001/0.000001; <0.000001/0.000003; <0.000001/0.000005, respectively) and significantly down-regulated during- and after-treatment in sustained-virological-responders (SVR). MiRNA-profiles of IC and SVR clustered in the heatmap. Liver-miRNAs were combined with miR-335, miR-126 and miR-320a (internal controls) to build a MiR-B-Index with 100% sensitivity, 83.3% and 92.5% specificity (−1.7 cut-off) in both training and validation cohorts to identify IC. MiR-B-Index (−5.72, −20.43/14.38) correlated with ALT (49, 10/2056 U/l, ρ = −0.497, p<0.001), HBV-DNA (4.58, undetectable/>8.3 Log10 IU/mL, ρ = −0.732, p<0.001) and HBsAg (3.40, 0.11/5.49 Log10 IU/mL, ρ = −0.883, p<0.001). At multivariate analysis HBV-DNA (p = 0.002), HBsAg (p<0.001) and infection-phase (p<0.001), but not ALT (p = 0.360) correlated with MiR-B-Index. In SVR to Peg-IFN/NUCs MiR-B-Index improved during-therapy and post-treatment reaching IC-like values (5.32, −1.65/10.91 vs 6.68, 0.54/9.53, p = 0.324) beckoning sustained HBV-immune-control earlier than HBsAg-decline.

Conclusions

Serum miRNA profile change dynamically during the different phases of chronic HBV infection. We identified a miRNA signature associated with both natural-occurring and therapy-induced immune control of HBV infection. The MiR-B-Index might be a useful biomarker for the early identification of the sustained switch from CHB to inactive HBV-infection in patients treated with antivirals.  相似文献   
957.
958.
Martin, P., Martínez‐Ansemil, E. & Sambugar, B. (2010). The Baikalian genus Rhyacodriloides in Europe: phylogenetic assessment of Rhyacodriloidinae subfam. n. within the Naididae (Annelida). —Zoologica Scripta, 39, 462–482. Two new species of the oligochaete genus Rhyacodriloides Chekanovskaya, Rhyacodriloides aeternorum sp. n. and Rhyacodriloides latinus sp. n., are described from subterranean water bodies of Italy and Slovenia. A comparison with the known species of this genus, Rhyacodriloides abyssalis Chekanovskaya, 1975 and Rhyacodriloides gladiiseta Martin & Brinkhurst, 1998, both from Lake Baikal, shows that the enigmatic ‘cellular masses’ of the latter two species must be interpreted as different, not homologous structures. As a result, R. gladiiseta is to be ascribed to the Phallodrilinae, a primarily marine naidid subfamily, mentioned for the first time in Lake Baikal, and placed in its own genus, Phallobaikalus gen. n. The two new species are morphologically very similar, but their penial setae differ slightly. The phylogenetic relationships of R. latinus sp. n. and R. abyssalis within the Naididae (formerly the Tubificidae) were investigated using a combination of three genes, one nuclear (18S rDNA) and two mitochondrial (12S rDNA and 16S rDNA). A fragment of the mitochondrial COI gene, used as a barcode, also genetically characterized all Rhyacodriloides species. Sequences of 34 Naididae were obtained from EMBL, representative of five naidid subfamilies, and including five oligochaete outgroups. The data were analysed by parsimony, maximum likelihood and Bayesian inference. Taken in combination, the three genes investigated confirm that the two Rhyacodriloides species analysed are closer to each other than to any other naidid species. However, they are separated by 16S and COI distances that amount to 18.5% and 27.2%, respectively, suggesting an ancient separation between species, in good accordance with their present biogeographic distribution. Rhyacodriloides cannot be considered as a rhyacodriline, as assumed so far, as they never appeared related to this subfamily in any analysis considered. In contrast, they appear at the base of a naidid group, including the Tubificinae, the Phallodrilinae, the Limnodrilinae, as well as Branchiura sowerbyi, a species whose phylogenetic association with the rhyacodrilines has been questioned for a long time. Despite a lack of phylogenetic support, this position is congruent with a morphological reassessment of the Rhyacodrilinae, and strongly supports the erection of a new naidid subfamily to accommodate Rhyacodriloides.  相似文献   
959.
960.
Given ample evidence for shared cortical structures involved in encoding actions, whether or not subsequently executed, a still unsolved problem is the identification of neural mechanisms of motor inhibition, preventing “covert actions” as motor imagery from being performed, in spite of the activation of the motor system. The principal aims of the present study were the evaluation of: 1) the presence in covert actions as motor imagery of putative motor inhibitory mechanisms; 2) their underlying cerebral sources; 3) their differences or similarities with respect to cerebral networks underpinning the inhibition of overt actions during a Go/NoGo task. For these purposes, we performed a high density EEG study evaluating the cerebral microstates and their related sources elicited during two types of Go/NoGo tasks, requiring the execution or withholding of an overt or a covert imagined action, respectively. Our results show for the first time the engagement during motor imagery of key nodes of a putative inhibitory network (including pre-supplementary motor area and right inferior frontal gyrus) partially overlapping with those activated for the inhibition of an overt action during the overt NoGo condition. At the same time, different patterns of temporal recruitment in these shared neural inhibitory substrates are shown, in accord with the intended overt or covert modality of action performance. The evidence that apparently divergent mechanisms such as controlled inhibition of overt actions and contingent automatic inhibition of covert actions do indeed share partially overlapping neural substrates, further challenges the rigid dichotomy between conscious, explicit, flexible and unconscious, implicit, inflexible forms of motor behavioral control.  相似文献   
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