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141.
PSP (parotid secretory protein)/SPLUNC2 (short palate, lung and nasal epithelium clone 2) is expressed in human salivary glands and saliva. The protein exists as an N-glycosylated and non-glycosylated form and both appear to induce agglutination of bacteria, a major antibacterial function for salivary proteins. Both forms of PSP/SPLUNC2 bind LPS (lipopolysaccharide), suggesting that the protein may also play an anti-inflammatory role. Based on the predicted structure of PSP/SPLUNC2 and the location of known antibacterial and anti-inflammatory peptides in BPI (bactericidal/permeability-increasing protein) and LBP (LPS-binding protein), we designed GL13NH2 and GL13K, synthetic peptides that capture these proposed functions of PSP/SPLUNC2. GL13NH3 agglutinates bacteria, leading to increased clearance by macrophages and reduced spread of infection in a plant model. GL13K kills bacteria with a minimal inhibitory concentration of 5-10 μg/ml, kills bacteria in biofilm and retains activity in 150?mM NaCl and 50% saliva. Both peptides block endotoxin action, but only GL13K appears to bind endotoxin. The peptides do not cause haemolysis, haemagglutination in serum, inhibit mammalian cell proliferation or induce an inflammatory response in macrophages. These results suggest that the GL13NH2 and the modified peptide GL13K capture the biological activity of PSP/SPLUNC2 and can serve as lead compounds for the development of novel antimicrobial and anti-inflammatory peptides.  相似文献   
142.

Back ground

Although phlebotomy is a common procedure, there is limited information concerning to documented complications of venipuncture.

Case presentation

A 45 year old left- handed woman was refered for elecrodiagnostic study with dysesthesia and pain in left medial forearm. She noted these symptoms three weeks after phelebotomy. Electrodiagnostic study showed severe involvement of left side Medial Antebrachial Cutaneous nerve (MAC nerve).

Conclusion

Phelebotomy is a cause of MAC nerve injury. Electrodiagnostic testing can be helpful in evaluating cases of sensory disturbance after phlebotomy.  相似文献   
143.

Background

Nonalcoholic steatohepatitis (NASH), a progressive stage of nonalcoholic fatty liver disease (NAFLD), is characterized by steatosis (accumulation of triacylglycerols within hepatocytes) along with inflammation and ballooning degeneration. It has been suggested that oxidative stress may play an important role in the progress of NAFLD to NASH. The aim of present study was to determine whether antioxidant supplementations using EUK-8, EUK-134 and vitamin C could improve the biochemical and histological abnormalities associated with diet-induced NASH in rats.

Methods

NASH was induced in male N-Mary rats by feeding a methionine - choline deficient (MCD) diet. The rats were fed either normal chow or MCD diet for 10 weeks. After NASH development, the MCD-fed rats were randomly divided into four groups of six: the NASH group that received MCD diet, the EUK-8 group which was fed MCD diet plus EUK-8, the EUK-134 group which was fed MCD diet plus EUK-134 and the vitamin C group which received MCD diet plus vitamin C. EUK-8, EUK-134 and vitamin C (30 mg/kg body weight/day) were administered by gavage for eight weeks.

Results

Treatment of MCD-fed rats with salens reduced the sera aminotransferases, cholesterol, low density lipoprotein contents, the extent of lipid peroxidation and protein carbonylation whereas the HDL-C cholesterol levels were significantly increased. In addition, EUK-8 and EUK-134 improved steatosis, ballooning degeneration and inflammation in liver of MCD-fed rats.

Conclusion

Antioxidant (EUK-8, EUK-134 and vitamin C) supplementation reduces NASH-induced biochemical and histological abnormalities, pointing out that antioxidant strategy could be beneficial in treatment of NASH.  相似文献   
144.
A computational framework was developed to simulate the bone remodelling process as a structural topology optimisation problem. The mathematical formulation of the Level Set technique was extended and then implemented into a coronal plane model of the proximal femur to simulate the remodelling of internal structure and external geometry of bone into the optimal state. Results indicated that the proposed approach could reasonably mimic the major geometrical and material features of the natural bone. Simulation of the internal bone remodelling on the typical gross shape of the proximal femur, resulted in a density distribution pattern with good consistency with that of the natural bone. When both external and internal bone remodelling were simulated simultaneously, the initial rectangular design domain with a regularly distributed mass reduced gradually to an optimal state with external shape and internal structure similar to those of the natural proximal femur.  相似文献   
145.
A series of eight novel diamminetetrakis(carboxylato)platinum(IV) complexes was synthesized and characterized by multinuclear (1) H-, (13) C-, (15) N-, and (195) Pt-NMR spectroscopy. Their antiproliferative potency was evaluated in three human cancer cell lines representing ovarian (CH1), lung (A549), and colon carcinoma (SW480). In cisplatin-sensitive CH1 cancer cells, cytotoxicity was found in the low micromolar range, whereas, in inherently cisplatin-resistant A549 and SW480 cells, the activity was very low or negligible. Astonishingly, raise in lipophilicity of the complexes, as found in the case of cisplatin analogs, did not result in a significant enhancement of the cytotoxic effect.  相似文献   
146.
Formation of the ventral furrow in the Drosophila embryo relies on the apical constriction of cells in the ventral region to produce bending forces that drive tissue invagination. In our recent paper we observed that apical constrictions during the initial phase of ventral furrow formation produce elongated patterns of cellular constriction chains prior to invagination and argued that these are indicative of tensile stress feedback. Here, we quantitatively analyze the constriction patterns preceding ventral furrow formation and find that they are consistent with the predictions of our active-granular-fluid model of a monolayer of mechanically coupled stress-sensitive constricting particles. Our model shows that tensile feedback causes constriction chains to develop along underlying precursor tensile stress chains that gradually strengthen with subsequent cellular constrictions. As seen in both our model and available optogenetic experiments, this mechanism allows constriction chains to penetrate or circumvent zones of reduced cell contractility, thus increasing the robustness of ventral furrow formation to spatial variation of cell contractility by rescuing cellular constrictions in the disrupted regions.  相似文献   
147.
A bench-scale integrated process based on submerged aerobic powdered activated carbon-membrane bioreactor (PAC-MBR) has been utilized and established for the treatment of landfill leachate. The results showed that the submerged PAC-MBR system effectively removed biodegradable trace organic compounds by the average removal rate about 71 % at optimum food to microorganism (F/M) ratio of 0.4 gCOD/g day under a HRT of 24 h. Adding nanofiltration (NF) process increased the treatment efficiency up to 99 %. Further, adding powdered activated carbon to activated sludge (AS) resulted in a higher adsorption capacity in comparison with AS. Adsorption isotherms were investigated and fitted by the Langmuir and Freundlich isotherm models in which the Langmuir model performed better. The specific oxygen uptake rate (SOUR) showed that adding PAC reduces the effects of COD on microorganism activities. NH3–N, TKN and Heavy metals removal efficiency amounted to 97 ± 2, 96 ± 2, and 99 ± 2 %, respectively.  相似文献   
148.
149.
BACKGROUND: Our objective was to evaluate the use of special education services by children with orofacial clefts (OFCs). METHODS: We linked the birth certificates of children born from 1982–2001 in five counties of metropolitan Atlanta to a population‐based birth defects surveillance system to identify children with OFCs, and to the special education files for the school years 1992–2004 to identify children who used special education services. The special education data contained exceptionalities and services rendered for each school year. Prevalence ratios (PRs) and 95% CIs were calculated. The data were stratified by race/ethnicity, maternal education, type of OFC, and the presence of associated major malformations. In addition, we assessed the age at which special education began and the amount of time spent receiving services. RESULTS: Of the 777 children with OFCs, 201 (26%) were in special education at least 1 year compared with 8% of the children who had no major birth defects, yielding a PR of 3.2 (95% CI: 2.9–3.6). The most common exceptionality or service for children with an OFC was speech and language services. Compared with children with no birth defects, children with an OFC were four times more likely to be in this exceptionality (PR 3.8; 95% CI: 3.3–4.3). After excluding children in speech and language services, children with OFCs were still more likely to use special education services (PR 2.4; 95% CI: 1.7–3.2). CONCLUSIONS: Children with OFCs used special education services more often than children without birth defects. This information can help in planning for future population needs. Birth Defects Research (Part A), 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
150.
The global soil carbon pool is approximately three times larger than the contemporary atmospheric pool, therefore even minor changes to its integrity may have major implications for atmospheric CO2 concentrations. While theory predicts that the chemical composition of organic matter should constitute a master control on the temperature response of its decomposition, this relationship has not yet been fully demonstrated. We used laboratory incubations of forest soil organic matter (SOM) and fresh litter material together with NMR spectroscopy to make this connection between organic chemical composition and temperature sensitivity of decomposition. Temperature response of decomposition in both fresh litter and SOM was directly related to the chemical composition of the constituent organic matter, explaining 90% and 70% of the variance in Q10 in litter and SOM, respectively. The Q10 of litter decreased with increasing proportions of aromatic and O‐aromatic compounds, and increased with increased contents of alkyl‐ and O‐alkyl carbons. In contrast, in SOM, decomposition was affected only by carbonyl compounds. To reveal why a certain group of organic chemical compounds affected the temperature sensitivity of organic matter decomposition in litter and SOM, a more detailed characterization of the 13C aromatic region using Heteronuclear Single Quantum Coherence (HSQC) was conducted. The results revealed considerable differences in the aromatic region between litter and SOM. This suggests that the correlation between chemical composition of organic matter and the temperature response of decomposition differed between litter and SOM. The temperature response of soil decomposition processes can thus be described by the chemical composition of its constituent organic matter, this paves the way for improved ecosystem modeling of biosphere feedbacks under a changing climate.  相似文献   
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