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101.
Besides regulating calcium homeostasis, the effects of vitamin D on vascular tone and metabolic disturbances remain scarce in the literature despite an increase intake with high-fructose corn syrup worldwide. We investigated the effects of calcitriol, an active form of vitamin D, on vascular relaxation, glucose tolerance, and visceral fat pads in fructose-fed rats. Male Wistar-Kyoto rats were divided into 4 groups (n = 6 per group). Group Con: standard chow diet for 8 weeks; Group Fru: high-fructose diet (60% fructose) for 8 weeks; Group Fru-HVD: high-fructose diet as Group Fru, high-dose calcitriol treatment (20 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding; and Group Fru-LVD: high-fructose diet as Group Fru, low-dose calcitriol treatment (10 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding. Systolic blood pressure was measured twice a week by the tail-cuff method. Blood was examined for serum ionized calcium, phosphate, creatinine, glucose, triglycerides, and total cholesterol. Intra-peritoneal glucose intolerance test, aortic vascular reactivity, the weight of visceral fat pads, adipose size, and adipose angiotensin II levels were analyzed at the end of the study. The results showed that the fructose-fed rats significantly developed hypertension, impaired glucose tolerance, heavier weight and larger adipose size of visceral fat pads, and raised adipose angiotensin II expressions compared with the control rats. High- and low-dose calcitriol reduced modestly systolic blood pressure, increased endothelium-dependent aortic relaxation, ameliorated glucose intolerance, reduced the weight and adipose size of visceral fat pads, and lowered adipose angiotensin II expressions in the fructose-fed rats. However, high-dose calcitriol treatment mildly increased serum ionized calcium levels (1.44 ± 0.05 mmol/L). These results suggest a protective role of calcitriol treatment on endothelial function, glucose tolerance, and visceral adiposity in fructose-fed rats.  相似文献   
102.
Yao J  Xu Y  Ji F  Wang C  Zhang Y  Ni J  Wang R 《Peptides》2011,32(5):1047-1054
The monocyte locomotion inhibitory factor (MLIF) is an anti-inflammatory oligopeptide produced by Entamoeba histolytica. Among its different effects, it inhibits locomotion of human monocytes, hence its original name. The carboxyl-terminal end group Cys-Asn-Ser is the pharmacophore of anti-inflammatory peptide Met-Gln-Cys-Asn-Ser. In this study, the N-terminal of Cys-Asn-Ser was modified. With the aim to enhance the antioxidant ability and penetrability of Cys-Asn-Ser, we designed and synthesized two tetrapeptides Tyr-Cys-Asn-Ser and His-Cys-Asn-Ser. The neuroprotective effects of Tyr-Cys-Asn-Ser and His-Cys-Asn-Ser on focal ischemia reperfusion were investigated, and their pharmacological activities compared with Cys-Asn-Ser were studied. In order to study the mechanism of neuroprotective effect of these peptides, the level of oxidative stress markers malondialdehyde (MDA) and superoxide dismutase (SOD) and pro-inflammatory factors interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and myeloperoxidase (MPO) were detected in brain tissue homogenate.  相似文献   
103.
This study sought to determine whether invariant NKT (iNKT) cells play an essential role in inflammation-induced preterm delivery. Preterm delivery and fetal death rates were determined in wild-type (WT) C57BL/6 mice and iNKT cell-deficient Jα18(-/-) mice injected i.p. with LPS. The percentages of decidual immune cells, including activated subsets, and costimulatory molecule expression were analyzed by flow cytometry. Th1 and Th2 cytokine production in the culture supernatants of decidual mononuclear cells was measured by ELISA. To some extent, Jα18(-/-) mice were resistant to LPS-induced preterm delivery. The proportions of decidual CD3(+) and CD49b(+) cells were slightly lower in Jα18(-/-) mice than in WT Jα18(+/+) mice, whereas almost no CD3(+)CD49b(+) cells could be found in Jα18-null mice. The percentages of activated decidual DCs, T cells, and NK cells were significantly lower in LPS-treated Jα18(-/-) mice than in WT mice. The CD40, CD80, and CD86 expression levels on decidual CD11c(+) cells from Jα18(-/-) mice were also significantly lower than in WT mice. Mean concentrations of Th1 cytokines IFN-γ and IL-12p70 in the culture supernatants of decidual mononuclear cells from LPS-treated Jα18(-/-) mice were apparently lower than those of LPS-induced WT mice. Additionally, the proportions of activated CD11c(+) cells, CD3(+) cells, and CD49b(+) cells in LPS-induced preterm delivery mice were strikingly higher in both WT and null mice when compared with the control PBS group and LPS-injected but normally delivered mice. Our results suggest that iNKT cells may play an essential role in inflammation-induced preterm birth.  相似文献   
104.
Altered levels of global DNA methylation and gene silencing through methylation of promoter regions can impact cancer risk, but little is known about their environmental determinants. We examined the association between lifestyle factors and levels of global genomic methylation and IL-6 promoter methylation in white blood cell DNA of 165 cancer-free subjects, 18–78 years old, enrolled in the COMIR (Commuting Mode and Inflammatory Response) study, New York, 2009–2010. Besides self-administrated questionnaires on diet and physical activity, we measured weight and height, white blood cell (WBC) counts, plasma levels of high sensitivity C-reactive protein (hs-CRP), and genomic (LINE-1) and gene-specific methylation (IL-6) by pyrosequencing in peripheral blood WBC. Mean levels of LINE-1 and IL-6 promoter methylation were 78.2% and 57.1%, respectively. In multivariate linear regression models adjusting for age, gender, race/ethnicity, body mass index, diet, physical activity, WBC counts and CRP, only dietary folate intake from fortified foods was positively associated with LINE-1 methylation. Levels of IL-6 promoter methylation were not significantly correlated with age, gender, race/ethnicity, body mass index, physical activity or diet, including overall dietary patterns and individual food groups and nutrients. There were no apparent associations between levels of methylation and inflammation markers such as WBC counts and hs-CRP. Overall, among several lifestyle factors examined in association with DNA methylation, only dietary folate intake from fortification was associated with LINE-1 methylation. The long-term consequence of folate fortification on DNA methylation needs to be further evaluated in longitudinal settings.  相似文献   
105.
Preimplantation genetic diagnosis (PGD) is employed increasingly to allow transfer of embryos to the uterus in assisted reproduction procedures. There are three stages of biopsy: polar bodies, one or two blastomeres from the cleavage-stage embryos, and trophectoderm cells (∼5 cells) from the blastocyst-stage embryos. Validation of polymerase chain reaction (PCR)-based assays are challenging because only limited genetic material can be obtained for PGD. In the current study, we modified a valid single-cell PCR protocol for PGD using real-time PCR assay with fluorescence resonance energy transfer (FRET) hybridization probes followed by melting curve analysis. We optimized and clinically applied the protocol, permitting molecular genetic analysis to amplify a specific region on the beta-globin (HBB) gene for a couple, carriers of two mutations: c.-78A>G and c.52A>T. Among a total of eight embryos obtained after ovarian stimulation, a single blastomere per embryo at the six- to eight-cell stage was biopsied. This PGD method showed that four embryos were unaffected, two embryos were selected for transfer, and one pregnancy was achieved. Finally, a healthy male baby was delivered at 38 weeks’ gestation. The results obtained using the new method, FRET hybridization probes, were compared with findings using an existing method, primer extension minisequencing.  相似文献   
106.
107.
Fifty normal noninfarct patients and 12 cases with infarcts of the cerebrum were examined with routine magnetic resonance imaging and echo-planar diffusion-weighted imaging. The diffusion-weighted three-dimensional images were reconstructed with volume-rendering processing on workstation. Precentral gyrus, post-central gyrus, superior parietal lobule, superior frontal gyrus, precentral sulcus, central sulcus, postcentral sulcus, intraparietal sulcus and superior frontal sulcus were best shown of all structures with an arbitrary score of 2.61–2.77. Supramarginal gyrus, middle frontal gyrus, inferior frontal gyrus and lateral sulcus were clearly shown in the majority of the cerebra with average scores of 2.0–2.49; angular gyrus, inferior frontal sulcus and superior temporal gyrus were not demonstrated satisfactorily and their average scores were 1.67–1.89. Middle temporal gyrus, inferior temporal gyrus, superior temporal sulcus and inferior temporal sulcus were difficult to identify, and thus had average scores of 0.87–1.26. Brain surface structures were better displayed in the older group of individuals than in the younger group. The structures in the 12 cases with acute or chronic cerebrum infarcts were also satisfactorily demonstrated with this new technique.  相似文献   
108.
探讨枸杞多糖(Lycium barbarum polysaccharide,LBP)作为佐剂对H5亚型流感病毒全病毒灭活疫苗的体液免疫增强效果。将流感病毒A/Vietnam/1194/2004(H5N1)灭活疫苗与不同剂量的枸杞多糖混合后以腹腔注射的方式共同免疫小鼠,免疫后三周收集血清用于特异性抗体检测。实验中设立氢氧化铝佐剂组作对照共同评价LBP作为佐剂的免疫增强效果。结果显示,小鼠血清中针对H5灭活疫苗的特异性抗体水平在一定范围内随着LBP剂量的增加而提高。LBP在800μg剂量时血清特异性抗体水平较无佐剂组显著增强,并与氢氧化铝佐剂组大致相当。因而,LBP有可能成为一种有效的流感灭活疫苗免疫佐剂。  相似文献   
109.
Experimental residual dipolar couplings (RDCs) in combination with structural models have the potential for accelerating the protein backbone resonance assignment process because RDCs can be measured accurately and interpreted quantitatively. However, this application has been limited due to the need for very high-resolution structural templates. Here, we introduce a new approach to resonance assignment based on optimal agreement between the experimental and calculated RDCs from a structural template that contains all assignable residues. To overcome the inherent computational complexity of such a global search, we have adopted an efficient two-stage search algorithm and included connectivity data from conventional assignment experiments. In the first stage, a list of strings of resonances (CA-links) is generated via exhaustive searches for short segments of sequentially connected residues in a protein (local templates), and then ranked by the agreement of the experimental 13Cα chemical shifts and 15N-1H RDCs to the predicted values for each local template. In the second stage, the top CA-links for different local templates in stage I are combinatorially connected to produce CA-links for all assignable residues. The resulting CA-links are ranked for resonance assignment according to their measured RDCs and predicted values from a tertiary structure. Since the final RDC ranking of CA-links includes all assignable residues and the assignment is derived from a “global minimum”, our approach is far less reliant on the quality of experimental data and structural templates. The present approach is validated with the assignments of several proteins, including a 42 kDa maltose binding protein (MBP) using RDCs and structural templates of varying quality. Since backbone resonance assignment is an essential first step for most of biomolecular NMR applications and is often a bottleneck for large systems, we expect that this new approach will improve the efficiency of the assignment process for small and medium size proteins and will extend the size limits assignable by current methods for proteins with structural models.  相似文献   
110.

Introduction

Skin and soft tissue infections (SSTIs) are common infections occurring in ambulatory and inpatient settings. The extent of complications associated with these infections by diabetes status is not well established.

Methods

Using a very large repository database, we examined medical and pharmacy claims of individuals aged 0–64 between 2005 and 2010 enrolled in U.S. health plans. Diabetes, SSTIs, and SSTI-associated complications were identified by ICD-9 codes. SSTIs were stratified by clinical category and setting of initial diagnosis.

Results

We identified 2,227,401 SSTI episodes, 10% of which occurred in diabetic individuals. Most SSTIs were initially diagnosed in ambulatory settings independent from diabetes status. Abscess/cellulitis was the more common SSTI group in diabetic and non-diabetic individuals (66% and 59%, respectively). There were differences in the frequencies of SSTI categories between diabetic and non-diabetic individuals (p<0.01). Among SSTIs diagnosed in ambulatory settings, the SSTI-associated complication rate was over five times higher in people with diabetes than in people without diabetes (4.9% vs. 0.8%, p<0.01) and SSTI-associated hospitalizations were 4.9% and 1.1% in patients with and without diabetes, respectively. Among SSTIs diagnosed in the inpatient setting, bacteremia/endocarditis/septicemia/sepsis was the most common associated complication occurring in 25% and 16% of SSTIs in patients with and without diabetes, respectively (p<0.01).

Conclusions

Among persons with SSTIs, we found SSTI-associated complications were five times higher and SSTI-associated hospitalizations were four times higher, in patients with diabetes compared to those without diabetes. SSTI prevention efforts in individuals with diabetes may have significant impact on morbidity and healthcare resource utilization.  相似文献   
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