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901.
1-Glycosyl-4-phenyl triazoles have been prepared via a copper-mediated [3+2] cycloaddition of glycosyl azides with phenylacetylene. These triazoles have been evaluated for their ability to inhibit the enzymatic activity of glycosidases.  相似文献   
902.
Individuals value information that improves decision making. When social interactions complicate the decision process, acquiring information about others should be particularly valuable. In primate societies, kinship, dominance, and reproductive status regulate social interactions and should therefore systematically influence the value of social information, but this has never been demonstrated. Here, we show that monkeys differentially value the opportunity to acquire visual information about particular classes of social images. Male rhesus macaques sacrificed fluid for the opportunity to view female perinea and the faces of high-status monkeys but required fluid overpayment to view the faces of low-status monkeys. Social value was highly consistent across subjects, independent of particular images displayed, and only partially predictive of how long subjects chose to view each image. These data demonstrate that visual orienting decisions reflect the specific social content of visual information and provide the first experimental evidence that monkeys spontaneously discriminate images of others based on social status.  相似文献   
903.
Cucumber fruit mottle mosaic tobamovirus (CFMMV) causes severe mosaic symptoms and yellow mottling on leaves and fruits and, occasionally, severe wilting of cucumber (Cucumis sativus L.) plants. No genetic source of resistance against this virus has been identified in cucumber. The gene coding for the putative 54-kDa replicase gene of CFMMV was cloned into an Agrobacterium tumefaciens binary vector, and transformation was performed on cotyledon explants of a parthenocarpic cucumber cultivar. R1 seedlings were screened for resistance to CFMMV by symptom expression, back inoculation on an alternative host and ELISA. From a total of 14 replicase-containing R1 lines, eight resistant lines were identified. Line I44 – homozygous for the putative 54-kDa replicase gene – was immune to CFMMV infection by mechanical and graft inoculation, and to root infection following planting in CFMMV-infested soil. A substantial delay of symptom appearance was observed following infection by three additional cucurbit-infecting tobamoviruses. When used as a rootstock, line I44 protected susceptible cucumber scions from soil infection by CFMMV. This paper is the first report on protection of a susceptible cultivar against a soil-borne viral pathogen, by grafting onto a transgenic rootstock.  相似文献   
904.
905.

Background

Patients with type 1 diabetes (T1DM) have increased mortality from cardiovascular disease (CVD). Risk factors for CVD include an elevation of LDL (LDLp) and small HDL (sHDLp) particles, and a decrease in reverse cholesterol transport i.e. HDL-cholesterol efflux capacity (CEC). Our objective was to compare lipoprotein particles and CEC between T1DM and healthy controls (HC) and to explore the associations between NMR lipid particles and cholesterol efflux.

Methods

78 patients with T1DM and 59 HC underwent fasting lipoprotein profile testing by NMR and measurements of CEC by cell-based method. The associations between NMR lipid particles with CEC were analyzed using multivariable linear regression models.

Results

Youth with T1DM had higher total LDLp 724 [(563–985) vs 622 (476–794) nmol/L (P?=?0.011)] (Maahs et al. in Circulation 130(17):1532–58, 2014; Shah et al. in Pediatr Diabetes 16(5):367–74, 2015), sHDLp [11.20 (5.7–15.3) vs 7.0 (3.2–13.1) μmol/L (P?=?0.021)], and lower medium HDLp [11.20 (8.5–14.5) vs 12.3 (9–19.4), (P?=?0.049)] and lower CEC (0.98?±?0.11% vs 1.05?±?0.15%, P?=?0.003) compared to HC. Moreover, CEC correlated with sHDLp (β?=???0.28, P?=?0.045) and large HDLp (β?=?0.46, P?<?0.001) independent of age, sex, ethnicity, BMIz, HbA1c, hsCRP and total HDLp in the diabetic cohort.

Conclusions

Youth with T1DM demonstrated a more atherogenic profile including higher sHDL and LDLp and lower CEC. Future efforts should focus on considering adding lipoprotein particles and CEC in CVD risk stratification of youth with T1DM.Trial registration Clinical Trials Registration Number NCT02275091
  相似文献   
906.
The effect of a potent antimicrobial compound bearing 1,2,3‐triazole core and a tryptophan tail, triazole‐tryptophan hybrid (TTH), with bovine serum albumin (BSA) have been explored using various spectroscopic and molecular docking methods. Studies revealed that TTH strongly quenches the intrinsic fluorophore of BSA by a static quenching mechanism. Time‐resolved fluorescence spectra further confirmed the involvement of static quenching for TTH–BSA system. The calculated thermodynamic parameters; ΔH, ΔS, and ΔG showed that the binding process was spontaneous, exothermic and entropy driven. Synchronous fluorescence, three‐dimensional (3D) fluorescence and circular dichroism data revealed that TTH induces the structural alteration in BSA and enhances its stability. In silico study of TTH–BSA system showed that it binds with BSA at the site I of subdomain IIA. Both the experimental and in silico study showed that the hydrophobic and electrostatic interactions play a major role in TTH–BSA binding.  相似文献   
907.

Background

Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication of allogeneic hematopoietic cell transplantation (HCT). Epstein-Barr virus (EBV) reactivation (detectable DNAemia) predisposes to the development of PTLD.

Methods

We retrospectively studied 306 patients monitored for EBV DNAemia after Thymoglobulin-conditioned HCT to determine the utility of the monitoring in the management of PTLD. DNAemia was monitored weekly for ≥12 weeks post-transplantation.

Results

Reactivation was detected in 82% of patients. PTLD occurred in 14% of the total patients (17% of patients with reactivation). PTLD was treated with rituximab only when and if the diagnosis was established. This allowed us to evaluate potential DNAemia thresholds for pre-emptive therapy. We suggest 100,000–500,000?IU per mL whole blood as this would result in unnecessary rituximab administration to only 4–20% of patients and near zero mortality due to PTLD. After starting rituximab (for diagnosed PTLD), sustained regression of PTLD occurred in 25/25 (100%) patients in whom DNAemia became undetectable. PTLD progressed or relapsed in 12/17 (71%) patients in whom DNAemia was persistently detectable.

Discussion

In conclusion, for pre-emptive therapy of PTLD, we suggest threshold DNAemia of 100,000–500,000?IU/mL. Persistently detectable DNAemia after PTLD treatment with rituximab appears to have 71% positive predictive value and 100% negative predictive value for PTLD progression/relapse.  相似文献   
908.
909.
A series of lH-pyrazolo[3,4-b]quinolin-3-amine derivatives were synthesized and evaluated for anticancer efficacy in a panel of ten cancer cell lines, including breast (MDAMB-231 and MCF-7), colon (HCT-116, HCT-15, HT-29 and LOVO), prostate (DU-145 and PC3), brain (LN-229), ovarian (A2780), and human embryonic kidney (HEK293) cells, a non-cancerous cell line. Among the eight derivatives screened, compound QTZ05 had the most potent and selective antitumor efficacy in the four colon cancer cell lines, with IC50 values ranging from 2.3 to 10.2?µM. Furthermore, QTZ05 inhibited colony formation in HCT-116 cells in a concentration-dependent manner. Cell cycle analysis data indicated that QTZ05 caused an arrest in the sub G1 cell cycle in HCT-116 cells. QTZ05 induced apoptosis in HCT-116 cells in a concentration-dependent manner that was characterized by chromatin condensation and increase in the fluorescence of fluorochrome-conjugated Annexin V. The findings from our study suggest that QTZ05 may be a valuable prototype for the development of chemotherapeutics targeting apoptotic pathways in colorectal cancer cells.  相似文献   
910.
Renin angiotensin system (RAS) comprising Angiotensin converting enzyme (ACE), Angiotensin II (Ang II) and its receptor Angiotensin II receptor type I (AGTR1), plays a critical role in several diseases including cancer. A single nucleotide polymorphism (SNP) A1166C located in 3′ untranslated region (UTR) of AGTR1 and an insertion/deletion (I/D) polymorphism present in intron 16 of ACE gene have been associated with many diseases, but their association with Breast cancer (BCa) is still debatable. Here, we for the first time investigated the association of these polymorphisms in a North Indian BCa cohort including 161 patients and 152 healthy women. The polymorphisms were evaluated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) respectively. The association between these polymorphisms and BCa risk was estimated by calculating Odds Ratio (OR) and chi-square (χ2) test. The DD genotype/D allele of ACE (I/D) polymorphism and “AC and CC” genotype/C allele of AGTR1 (A1166C) polymorphism were associated with higher risk of BCa when evaluated independently. Furthermore, interaction analysis of “AC and CC” and DD genotype and combination of “C and D” alleles of both polymorphisms revealed significantly greater BCa risk than that observed independently. Conclusively, women harboring “AC or CC” genotype/C allele for AGTR1 (A1166C) polymorphism and DD genotype/D allele for ACE (I/D) polymorphisms have a predisposition to develop more aggressive disease with advanced staging and larger tumor size. Our study indicates importance of genetic screening based on these polymorphisms for women, who may have higher risk of BCa.  相似文献   
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