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61.
Objectives: HIV-related immunosuppression has been associated with the development of AIDS-defining malignancies. We examined the overall survival of HIV-infected patients who developed cancer. Design: A retrospective cohort study. Methods: Using the Taiwan Longitudinal Health Insurance Database, we compared patients diagnosed with HIV (n = 9918) between January 1, 2002, and December 31, 2007 with age-matched controls (n = 99,180). Each patient was followed until the end of 2009 (least 2 years after the initial HIV diagnosis) to evaluate the incidence of malignancies. Results: The risk of overall malignancies in the HIV-infected cohort was 1.88 times higher than the risk of a first malignancy in the age-matched non-HIV infected cohort (incidence rate ratio [IRR]) = 2.05, p < 0.0001). The diagnosis of a malignancy was negatively correlated with survival in the HIV-infected cohort (p < 0.0011), and HIV infection had a synergistic effect on the survival of patients with malignancies compared with the non-HIV infected cohort, all of who had been newly diagnosed with cancer (p < 0.0001). However, the difference in the risk of developing nasopharyngeal carcinoma (NPC), a highly prevalent malignancy in Taiwan, between the two cohorts was not significant (IRR = 0.22, 95% CI = 0.03–1.65). Conclusions: The risk of cancer in HIV-infected patients in Taiwan has increased significantly in the era of highly active antiretroviral therapy. A history of HIV significantly affected the survival of the patients in our study cohort after they developed cancer.Evidence level: 2B.  相似文献   
62.
Intrinsically photosensitive retinal ganglion cells (ipRGCs) are depolarized by light by two mechanisms: directly, through activation of their photopigment melanopsin; and indirectly through synaptic circuits driven by rods and cones. To learn more about the rod and cone circuits driving ipRGCs, we made multielectrode array (MEA) and patch-clamp recordings in wildtype and genetically modified mice. Rod-driven ON inputs to ipRGCs proved to be as sensitive as any reaching the conventional ganglion cells. These signals presumably pass in part through the primary rod pathway, involving rod bipolar cells and AII amacrine cells coupled to ON cone bipolar cells through gap junctions. Consistent with this interpretation, the sensitive rod ON input to ipRGCs was eliminated by pharmacological or genetic disruption of gap junctions, as previously reported for conventional ganglion cells. A presumptive cone input was also detectable as a brisk, synaptically mediated ON response that persisted after disruption of rod ON pathways. This was roughly three log units less sensitive than the rod input. Spectral analysis revealed that both types of cones, the M- and S-cones, contribute to this response and that both cone types drive ON responses. This contrasts with the blue-OFF, yellow-ON chromatic opponency reported in primate ipRGCs. The cone-mediated response was surprisingly persistent during steady illumination, echoing the tonic nature of both the rod input to ipRGCs and their intrinsic, melanopsin-based phototransduction. These synaptic inputs greatly expand the dynamic range and spectral bandpass of the non-image-forming visual functions for which ipRGCs provide the principal retinal input.  相似文献   
63.
Non-melanoma skin cancer (NMSC) is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser473 & thr308) were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion.  相似文献   
64.
Aberrant expression of the tripartite motif containing 59 (TRIM59) has been reported to participate in the development and progression of various human cancers. However, its expression pattern and cellular roles in pancreatic cancer (PC) remains unclear. In our study, we found that TRIM59 expression was significantly increased in PC tissues and was positively correlated with several malignant behaviors and poor overall survival of PC patients based on bioinformatics analysis and immunohistochemistry staining. Functionally, small interfering RNA–mediated TRIM59 depletion inhibited cell proliferation and migration in vitro, while TRIM59 overexpression promoted cell proliferation and migration in vitro and drove tumor growth and liver metastasis in vivo. Mechanically, TRIM59 was found to enhance glycolysis through activating the PI3K/AKT/mTOR pathway, ultimately contributing to PC progression. Taken together, our results demonstrate that TRIM59 may be a potential predictor for PC and promotes PC progression via the PI3K/AKT/mTOR-glycolysis signaling pathway, which establishes the rationale for targeting the TRIM59-related pathways to treat PC.  相似文献   
65.
Molecular and Cellular Biochemistry - Pathological cardiac hypertrophy is ultimately accompanied by cardiomyocyte apoptosis. Apoptosis mainly related to calpain-1-mediated apoptotic pathways....  相似文献   
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68.
Gallbladder carcinoma (GBC) is one of the mostly aggressive and fatal malignancies. However, little is known about the oncogenic genes that contributed to the development of GBC. Zinc finger X-chromosomal protein (ZFX) was a novel member of the Krueppel C2H2-type zinc-finger protein family and its down-regulation led to impaired cell growth in human laryngeal squamous cell carcinoma. Here, we aim to investigate the function of ZFX in GBC cell proliferation and migration. Loss of function analysis was performed on GBC cell line (GBC-SD) using lentivirus-mediated siRNA against ZFX. The proliferation, in vitro tumorigenesis (colony-formation) ability as well as cell migration was significantly suppressed after GBC-SD cells which were infected with ZFX-siRNA-expressing lentivirus (Lv-shZFX). Our finding suggested that ZFX promoted the growth and migration of GBC cells and could present a potential molecular target for gene therapy of GBC.  相似文献   
69.

Aim

Our aim was to improve the prediction of Zn bioavailability to wheat grown on low-Zn soils. The classical approach that directly relates Zn in a certain soil extract to Zn uptake has been shown to be inadequate in many cases. We tested a stepwise approach where the steps of the uptake process are characterized with, respectively, Zn solid-solution distribution, adsorption of Zn to root surface, Zn uptake into root and Zn translocation to shoot.

Methods

Two pot experiments were done with wheat grown on nine low-Zn soils varying widely in pH, clay and organic matter content. Soluble Zn concentrations in two soil extracts (DTPA and CaCl2) were measured. Free Zn ion concentrations in CaCl2 soil extracts were determined with the Donnan Membrane Technique. These Zn concentrations were then related to plant Zn uptake following both the direct and the stepwise approach.

Results

In the direct approach, Zn in the DTPA extract was a better predictor for shoot Zn uptake than Zn in the CaCl2 extract. In the stepwise approach, the relationship between Zn in CaCl2 extracts and the root surface adsorbed Zn was pH-dependent and nonlinear. Root surface adsorbed Zn was linearly related to root Zn uptake, and the latter was linearly related to the shoot Zn uptake. The stepwise approach improved the Zn uptake prediction compared to the direct approach and was also validated for different wheat cultivars.

Conclusions

The adsorption of Zn on the root surface is pH dependent and nonlinear with respect to the soil Zn concentration, and a useful proxy for bioavailable Zn over a wide range of soils.  相似文献   
70.
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