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51.
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   
52.

Background

The aim of this study was to evaluate whether arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) can reliably quantify perfusion deficit as compared to dynamic susceptibility contrast (DSC) perfusion MRI.

Methods

Thirty-nine patients with acute ischemic stroke in the anterior circulation territory were recruited. All underwent ASL and DSC MRI perfusion scans within 30 hours after stroke onset and 31 patients underwent follow-up MRI scans. ASL cerebral blood flow (CBF) and DSC time to maximum (Tmax) maps were used to calculate the perfusion defects. The ASL CBF lesion volume was compared to the DSC Tmax lesion volume by Pearson''s correlation coefficient and likewise the ASL CBF and DSC Tmax lesion volumes were compared to the final infarct sizes respectively. A repeated measures analysis of variance and least significant difference post hoc test was used to compare the mean lesion volumes among ASL CBF, DSC Tmax >4–6 s and final infarct.

Results

Mean patient age was 72.6 years. The average time from stroke onset to MRI was 13.9 hours. The ASL lesion volume showed significant correlation with the DSC lesion volume for Tmax >4, 5 and 6 s (r = 0.81, 0.82 and 0.80; p<0.001). However, the mean lesion volume of ASL (50.1 ml) was significantly larger than those for Tmax >5 s (29.2 ml, p<0.01) and Tmax >6 s (21.8 ml, p<0.001), while the mean lesion volumes for Tmax >5 or 6 s were close to mean final infarct size.

Conclusion

Quantitative measurement of ASL perfusion is well correlated with DSC perfusion. However, ASL perfusion may overestimate the perfusion defects and therefore further refinement of the true penumbra threshold and improved ASL technique are necessary before applying ASL in therapeutic trials.  相似文献   
53.
Increasing evidence indicates that antibody-dependent cellular cytotoxicity (ADCC) contributes to the control of HIV/SIV infection. However, little is known about the ADCC function of natural killer (NK) cells in non-human primate model. Here we demonstrated that ADCC function of NK cells was significantly compromised in chronic SIV/SHIV infection, correlating closely with the expression of FcγRIIIa receptor (CD16) on NK cells. CD32, another class of IgG Fc receptors, was identified on NK cells with higher expression in the infected macaques and the blockade of CD32 impacted the ability of NK cells to respond to antibody-coated target cells. The inhibition of matrix metalloproteases (MMPs), a group of enzymes normally involved in tissue/receptor remodeling, could restore NK cell-mediated ADCC with increased CD16 expression on macaque NK cells. These data offer a clearer understanding of NK cell-mediated ADCC in rhesus macaques, which will allow us to evaluate the ADCC repertoire arising from preclinical vaccination studies in non-human primates and inform us in the future design of effective HIV vaccination strategies.  相似文献   
54.
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   
55.

Objective

This study determined the prevalence and factors associated with peripheral neuropathy (PN) in subjects with diabetes mellitus, impaired glucose regulation (IGR), and normal glucose tolerance (NGT) in a community-based Chinese population.

Research Design and Methods

A total of 2035 subjects in Shanghai were classified as having NGT, IGR, or diabetes. All subjects underwent complete foot examination. PN was assessed according to the neuropathy symptom and neuropathy disability scores. Binary logistic regression was performed to analyze the contributions of factors to PN.

Results

The prevalence of PN was 8.4%, 2.8%, and 1.5% in diabetes mellitus, IGR, and NGT subjects, respectively (P<0.05 for diabetes vs. NGT, and IGR). The subjects with known diabetes had the highest frequency of PN (13.1%). Among the subjects without diabetes, those with PN were older, had a higher waist circumference and 2-h postprandial plasma glucose levels, and were more likely to be hypertensive. Among the IGR subjects, other than age, the 2-h postprandial plasma glucose level was an independent factor significantly associated with PN. Meanwhile, among the subjects with diabetes, PN was associated with fasting plasma glucose, duration of diabetes, and decreased estimated glomerular filtration rate.

Conclusions

The prevalence of PN is slightly higher in individuals with IGR than that in individuals with NGT, but small fibre damage in IGR as the earliest nerve fibre deficit may be underestimated in our study. As an independent risk factor, postprandial plasma glucose level may be an important target for strategies to prevent or improve PN in IGR subjects.  相似文献   
56.
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   
57.
Positive species interactions are ubiquitous in natural communities, but the mechanisms through which they operate are poorly understood. One proposed mechanism is resource conversion – the conversion by a benefactor species of a resource from a resource state that is inaccessible to a potential beneficiary species into a resource state that is accessible. Such conversion often occurs as a byproduct of resource consumption, and sometimes in exchange for non-resource benefits to the benefactor species. At least five known classes of interactions, including both facilitative and mutualistic ones, may be classified as resource conversion interactions. We formulated a generalizable mathematical model for resource conversion interactions and examined two model variants that represent processing chain and nurse plant interactions. We examined the conditions under which these conformed to the stress-gradient hypothesis (SGH), which predicts increased interaction benefits in more stressful environments. These yielded four key insights: 1) resource conversion interactions can be positive (towards the resource recipient) only when facilitator-mediated resource conversion is more efficient than the baseline, spontaneous, facilitator-independent resource conversion; 2) the sign of resource conversion interaction outcomes never switches (e.g. from net positive to net negative) with changing levels of resource availability, when all other parameters are kept constant; 3) processing chain interactions at equilibrium can never be positive in a manner that conforms to the SGH; 4) nurse plant interactions can be positive and conform to the SGH, although the manner in which they do depends largely on how resource stress is defined, and the environmental supply rate of surface soil moisture. The first two insights are likely to be generalizable across all resource conversion interactions. The general agreement of the model with empirical studies suggest that resource conversion is the mechanism underlying the aforementioned interactions, and an ecologically meaningful way of classifying these previously unassociated positive species interactions.  相似文献   
58.
Plant Cell, Tissue and Organ Culture (PCTOC) - Tree peony (Paeonia sect. Moutan) is a world famous ornamental and economically important species, but it is recalcitrant to in vitro regeneration....  相似文献   
59.
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   
60.
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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