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1.
This study was designed to use multiple reaction monitoring (MRM) for accurate quantification of contact lens protein deposits. Worn lenses used with a multipurpose disinfecting solution were collected after wear. Individual contact lenses were extracted and then digested with trypsin. MRM in conjunction with stable-isotope-labeled peptide standards was used for protein quantification. The results show that lysozyme was the major protein detected from both lens types. The amount of protein extracted from contact lenses was affected by the lens material. Except for keratin-1 (0.83?±?0.61 vs 0.77?±?0.20, p?=?0.81) or proline rich protein-4 (0.11?±?0.04 vs 0.15?±?0.12, p?=?0.97), the amounts of lysozyme, lactoferrin, or lipocalin-1 extracted from balafilcon A lenses (12.9?±?9.01, 0.84?±?0.50 or 2.06?±?1.6, respectively) were significantly higher than that extracted from senofilcon A lenses (0.88?±?0.13, 0.50?±?0.10 or 0.27?±?0.23, respectively) (p?相似文献   

2.
Tear film protein deposition on contact lens hydrogels has been well characterized from the perspective of bacterial adhesion and viability. However, the effect of protein deposition on lens interactions with the corneal epithelium remains largely unexplored. The current study employs a live cell rheometer to quantify human corneal epithelial cell adhesion to soft contact lenses fouled with the tear film protein lysozyme. PureVision balafilcon A and AirOptix lotrafilcon B lenses were soaked for five days in either phosphate buffered saline (PBS), borate buffered saline (BBS), or Sensitive Eyes Plus Saline Solution (Sensitive Eyes), either pure or in the presence of lysozyme. Treated contact lenses were then contacted to a live monolayer of corneal epithelial cells for two hours, after which the contact lens was sheared laterally. The apparent cell monolayer relaxation modulus was then used to quantify the extent of cell adhesion to the contact lens surface. For both lens types, lysozyme increased corneal cell adhesion to the contact lens, with the apparent cell monolayer relaxation modulus increasing up to an order of magnitude in the presence of protein. The magnitude of this increase depended on the identity of the soaking solution: lenses soaked in borate-buffered solutions (BBS, Sensitive Eyes) exhibited a much greater increase in cell attachment upon protein addition than those soaked in PBS. Significantly, all measurements were conducted while subjecting the cells to moderate surface pressures and shear rates, similar to those experienced by corneal cells in vivo.  相似文献   

3.
4.
This study aimed at establishing a sensitive multiple reaction monitoring‐mass spectrometry (MRM‐MS) method for the quantification of the drug metabolizing cytochrome P450 (CYP)3A4 enzyme in human liver homogenates. Liver samples were subjected to trypsin digestion. MRM‐MS analyses were performed using three transitions optimized on one purified synthetic peptide unique to CYP3A4 and the standardizing protein, calnexin. Coefficient of variations for the precision and reproducibility of the MRM‐MS measurement were also determined. The method was applied to liver samples from ten non‐cholestatic donors and 34 cholestatic patients with primary biliary cholangitis (n = 12; PBC), primary sclerosing cholangitis (n = 10; PSC) or alcoholic liver disease (n = 12; ALD). The established method presented high sensitivity with limit of detection lower than 5 fmol, and was successfully applied for the absolute and relative quantification of CYP3A4 in both whole liver homogenate and microsomal fractions. When all groups were analyzed together, a significant correlation was observed for the MRM‐based CYP3A4 protein quantification in homogenates and microsomes (r = 0.49, p < 0.001). No statistically significant difference was detected between CYP3A4 levels in PSC, PBC, ALD and control samples. Finally, the MRM‐MS quantification of CYP3A4 in homogenates also correlated (r = 0.44; p < 0.05) with the level of enzyme activity in the same samples, as determined by measuring the chenodeoxycholic to hyocholic acid conversion. The established method provides a sensitive tool to evaluate the CYP3A4 protein in human liver homogenates from patients with normal or chronic/severe hepatic injury.  相似文献   

5.
BackgroundHomocysteine (Hcy) induced vascular endothelial dysfunction is known to be closely associated with oxidative stress and impaired NO system. 1,8-Dihydroxy-3-methoxy-6-methylanthracene-9,10-dione (physcion) has been known to has antioxidative and anti-inflammatory properties.PurposeThe purpose of the present study was to define the protective effect of physcion on Hcy-induced endothelial dysfunction and its mechanisms involved.Study Design and MethodsHyperhomocysteinemia (HHcy) rat model was induced by feeding 3% methionine. A rat thoracic aortic ring model was used to investigate the effects of physcion on Hcy-induced impairment of endothelium-dependent relaxation. Two doses, low (L, 30 mg/kg/day) and high (H, 50 mg/kg/day) of physcion were used in the present study. To construct Hcy-injured human umbilical vein endothelial cells (HUVECs) model, the cells treated with 3 mM Hcy. The effects of physcion on Hcy-induced HUVECs cytotoxicity and apoptosis were studied using MTT and flow cytometry. Confocal analysis was used to determine the levels of intracellular Ca2+. The levels of protein expression of the apoptosis-related markers Bcl-2, Bax, caspase-9/3, and Akt and endothelial nitric oxide synthase (eNOS) were evaluated by western blot.ResultsIn the HHcy rat model, plasma levels of Hcy and malondialdehyde (MDA) were elevated (20.45 ± 2.42 vs. 4.67 ± 1.94 μM, 9.42 ± 0.48 vs. 3.47 ± 0.59 nM, p < 0.001 for both), whereas superoxide dismutase (SOD) and nitric oxide (NO) levels were decreased (77.11 ± 4.78 vs. 115.02 ± 5.63 U/ml, 44.51 ± 4.45 vs. 64.18 ± 5.34 μM, p < 0.001 and p < 0.01, respectively). However, treatment with physcion significantly reversed these changes (11.82 ± 2.02 vs. 20.45 ± 2.42 μM, 5.97 ± 0.72 vs. 9.42 ± 0.48 nM, 108.75 ± 5.65 vs. 77.11 ± 4.78 U/ml, 58.14 ± 6.02 vs. 44.51 ± 4.45 μM, p < 0.01 for all). Physcion also prevented Hcy-induced impairment of endothelium-dependent relaxation in HHcy rats (1.56 ± 0.06 vs. 15.44 ± 2.53 nM EC50 for ACh vasorelaxation, p < 0.05 vs. HHcy). In Hcy-injured HUVECs, physcion inhibited the impaired viability, apoptosis and reactive oxygen species. Hcy treatment significantly increased the protein phosphorylation levels of p38 (2.26 ± 0.20 vs. 1.00 ± 0.12, p <0.01), ERK (2.11 ± 0.21 vs. 1.00 ± 0.11, p <0.01) and JNK. Moreover, physcion reversed the Hcy-induced apoptosis related parameter changes such as decreased mitochondrial membrane potential (MMP) and Bcl-2/Bax protein ratio, and increased protein expression of caspase-9/3 in HUVECs. Furthermore, the downregulation of Ca2+, Akt, eNOS and NO caused by Hcy were recovered with physcion treatment in HUVECs.ConclusionPhyscion prevents Hcy-induced endothelial dysfunction by activating Ca2+- and Akt-eNOS-NO signaling pathways. This study provides the first evidence that physcion might be a candidate agent for the prevention of cardiovascular disease induced by Hcy.  相似文献   

6.
7.
Kinetics of proton transfer between lysozyme and a pH indicator p-nitrophenol (p-Np) were measured by the temperature-jump method in a pH range of 6.0–7.0. Two well-defined relaxation processes were observed. The fast process (τ ? 15 μsec) was also observed for a lysozyme derivative succinylated at the terminal α-amino group of Lys 1. Therefore, the fast process was found to be attributable to the proton transfer reaction of His 15 with p-Np. The slow process (τ ? 50 μsec) was found to be characteristic of the proton transfer reaction of Glu 35, because it disappeared completely in solution containing a lysozyme derivative having an ester crosslink between the carboxyl group of Glu 35 and indol C-2 of Trp 108. The rate constants for proton transfer from Glu 35 and His 15 to p-Np were found to be 9 × 106/sec/M (±65%, 23°C) and 3 × 108/sec/M (±20%, 25°C), respectively. These data indicate that the proton of the carboxyl group of Glu 35 is kinetically stabilized in lysozyme.  相似文献   

8.
Urinary excretion of 17-ketosteroid (17-KS) was assessed in male pre-pubertal subjects aged (8–11 years; n = 90). Children living near sewage treatment plant and solid waste disposal plant (Group P) showed significantly higher levels of urinary 17-KS (Group P: 3.27 ± 1.63 µg/mL/CRE; p < 0.01) than children living in cleaner area (0.50 ± 0.53 µg/mL/CRE; Group C). Occurrence of urinary dibutyl phthalate in representative subjects of Group P (odds ratio: 9; p < 0.05; 95% of Confidence interval (CI) 1.93–72.99) was higher compared to Group C. Urinary concentrations of Cd (0.85 µg/g CRE ± 0.11), Mn (24.25 µg/g CRE ± 6.11) and Pb (12.39 µg/g CRE ± 2.86) in Group P were significantly (p < 0.01) higher than those found in Group C (Cd (0.28 µg/g CRE ± 0.03), Mn (13.33 µg/g CRE ± 3.20) and Pb (5.67 µg/g CRE ± 0.53)). Analyses of ambient air samples (PM10) in polluted area revealed major occurrence of phthalates, whereas derivatives of trifluoromethyl, dione, etc. were identified in PM2.5 fraction. Metal (Cd, Co, Mn and Pb) concentrations in ambient air (24 h, PM10) were higher in polluted area compared to cleaner area. We conclude that elevated levels of urinary 17-KS in Group P could be attributed to higher exposure of these subjects to Endocrine disrupting chemicals (EDCs) compared to Group C.  相似文献   

9.
The present study was designed to investigate the effect of Ramadan fasting on feelings, dietary intake, rating of perceived exertion (RPE) and repeated high-intensity short-term maximal performance. Thirteen physically active men (age: 21.2 ± 2.9 years, height: 175.6 ± 5.6 cm, body-mass: 72.4 ± 8.6 kg) performed a 5-m shuttle run test (6 × 30-s + 35-s of recovery in-between) during five experimental periods: fifteen days before Ramadan (BR), the first ten days of Ramadan (FR), the last ten days of Ramadan (ER), ten days after Ramadan (AR10) and 20 days after Ramadan (AR20). The study was carried out in Tunisia during the 2016 Ramadan month. During the 5-m shuttle run test, higher distance (HD), total distance (TD) and fatigue index (FI) were recorded. RPE was determined after a 5-min warm-up and after each repetition of the 5-m shuttle run test (the mean RPE score during the test was calculated). Moreover, a feelings scale (FS) was used after the warm-up and after the end of the 5-m shuttle run test. During the five experimental periods, dietary intake was assessed. The results showed that HD, TD and FI during the 5-m shuttle run test were not affected by Ramadan observance (p > 0.05). Likewise, FS scores recorded after the warm-up and the 5-m shuttle run test were not affected by Ramadan fasting (p > 0.05). However, mean RPE scores during the 5-m shuttle run test were significantly lower at ER (4.06 UA), AR10 (3.86 UA) and AR20 (3.71 UA) in comparison to BR (4.51 UA) (p < 0.05). The results showed also that Ramadan fasting has no adverse effect on energy intake, protein (g and %), fat (g and %) and carbohydrate (g). However, the fractional contribution of carbohydrate was significantly higher AR10 than FR (53.1% vs. 45.8%) and ER (53.1% vs. 46.5%) and AR20 than FR (5.92% vs. 45.8%) (p < 0.05). In conclusion, Ramadan fasting has no adverse effect on feelings, dietary intake, and short-term maximal performance. However, the RPE during repeated high intensity short-term maximal exercise was reduced AR20 in comparison to ER.

Abbreviations:

AR: After Ramadan; AR10: Ten days after Ramadan; AR20: Twenty days after Ramadan; BR: Fifteen days before Ramadan; ER: Last ten days of Ramadan; FI: Fatigue index; FR: First ten days of Ramadan; FS: Feelings scale; HD: Higher distance; PSQI: The Pittsburgh Sleep Quality Index; RPE: Rating of Perceived Exertion Scale; TD: Total distance  相似文献   


10.
ABSTRACT

Previous findings suggest that performing strength training (ST) in the evening may provide greater benefit for young individuals. However, this may not be optimal for the older population. The purpose of this study was to compare the effects of a 12-week ST program performed in the morning vs. evening on strength, functional capacity, metabolic biomarker and basal hormone concentrations in older women. Thirty-one healthy older women (66 ± 4 years, 162 ± 4 cm, 75 ± 13 kg) completed the study. Participants trained in the morning (M) (07:30, n = 10), in the evening (E) (18:00, n = 10), or acted as a non-training control group (C) (n = 11). Both intervention groups performed whole-body strength training with 3 sets of 10–12 repetitions with 2–3 minutes rest between sets. All groups were measured before and after the 12-week period with; dynamic leg press and seated-row 6-repetition maximum (6-RM) and functional capacity tests (30-second chair stands and arm curl test, Timed Up and Go), as well as whole-body skeletal muscle mass (SMM) (kg) and fat mass (FM-kg, FM%) assessed by bioelectrical impedance (BIA). Basal blood samples (in the intervention groups only) taken before and after the intervention assessed low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), blood glucose (GLU), triglycerides (TG), high-sensitive C-reactive protein (hsCRP) concentrations and total antioxidant status (TAS) after a 12 h fast. Hormone analysis included prolactin (PRL), progesterone (P) estradiol (ESTR), testosterone (T), follicle stimulating hormone (FSH), and luteinizing hormone (LH). While C showed no changes in any variable, both M and E significantly improved leg press (+ 46 ± 22% and + 21 ± 12%, respectively; p < 0.001) and seated-row (+ 48 ± 21% and + 42 ± 18%, respectively; p < 0.001) 6-RM, as well as all functional capacity outcomes (p < 0.01) due to training. M were the only group to increase muscle mass (+ 3 ± 2%, p < 0.01). Both M and E group significantly (p < 0.05) decreased GLU (–4 ± 6% and –8 ± 10%, respectively), whereas significantly greater decrease was observed in the E compared to the M group (p < 0.05). Only E group significantly decreased TG (–17 ± 25%, p < 0.01), whereas M group increased (+ 15%, p < 0.01). The difference in TG between the groups favored E compared to M group (p < 0.01). These results suggest that short-term “hypertrophic” ST alone mainly improves strength and functional capacity performance, but it influences metabolic and hormonal profile of healthy older women to a lesser extent. In this group of previously untrained older women, time-of-day did not have a major effect on outcome variables, but some evidence suggests that training in the morning may be more beneficial for muscle hypertrophy (i.e. only M significantly increased muscle mass and had larger effect size (M: g = 2 vs. E: g = 0.5).  相似文献   

11.
The in vitro caecal fermentation of five substrates low in starch and protein content [d-(+)-glucose (GLU), d-cellobiose (CEL), sugar beet pectin (PEC), sugar beet pulp (SBP) and wheat straw (WS)] was investigated using soft faeces from rabbits receiving different levels of cellobiose and soluble fibre as inoculum. A total of 24 rabbits were supplemented 3 levels of cellobiose in the drinking water (0.0, 7.5, 15.0 g/l) and fed two experimental diets containing either low soluble fibre (LSF) or high soluble fibre (HSF) levels (84.0 and 130 g/kg dry matter). All substrates were subjected to a two-step pepsin/pancreatin in vitro pre-digestion, and the whole residue was used as substrate for the in vitro incubations. Gas production was measured until 144 h, and volatile fatty acid (VFA) production was determined at 24 h incubation. Experimental treatments did not affect SBP fermentation and had only a subtle influence on fermentation of WS and GLU. In contrast, cellobiose supplementation × donors’ diet interactions were detected for most gas production parameters for CEL. Both the fractional gas production (k) and maximal gas production rates were linearly increased (p ≤ 0.042) and the initial delay in the onset of gas production (Lag) linearly decreased (p < 0.001) by cellobiose supplementation with the HSF inoculum, with no differences between the 7.5 and 15.0 doses. In contrast, with the LSF inoculum cellobiose supplementation only affected k values, which were quadratically increased (p = 0.043) and had maximal values for the 7.5 dose. A quadratic effect (p ≤ 0.018) of cellobiose supplementation was observed for total VFA production at 24 h when CEL and PEC were fermented, obtaining the maximal VFA production for the 7.5 dose of cellobiose. Total VFA production for CEL was greater with LSF than with HSF inoculum (20.7 vs. 12.9 mmol/l; p = 0.014), but the opposite was found for WS (3.97 vs. 6.21 mmol/l; p = 0.005). The use of LSF inoculum for CEL fermentation sharply reduced acetate (p = 0.001) and increased butyrate proportions (p ≤ 0.001) compared with the HSF inoculum. A positive relationship between total VFA caecal concentrations in rabbits receiving the same experimental treatments and in vitro values was only observed when WS was used as substrate (r = 0.90; p = 0.015; n = 6). The results suggest that experimental factors influenced the fermentative activity of caecal digesta, but the observed response differed with the incubated substrate, being the CEL the most affected.  相似文献   

12.
Residual effects of abamectin (0.02%), propargite (0.1%), dichlorvos (DDVP) (0.15%) and pymetrozine (0.15%) were determined on Orius albidipennis at laboratory conditions. Planted cucumbers were sprayed with the highest recommended concentrations of all insecticides and experimental treatments were monitored during 20 days based on the period of pesticides residues. On the first day after spraying, the greatest of mortality belonged to dichlorvos and pymetrozine (97 ± 1.22, 57 ± 3.1, respectively, p < 0.01), while abamectin and propargite had the highest mortality after four (44 ± 1.87 and 24 ± 2.91, respectively, p < 0.01) and eight (51 ± 2.91 and 17 ± 2.23, respectively, p < 0.01) days after spraying. At day 16th, post treatment, abamectin had the highest residual mortalities on O. albidipennis (15 ± 1.58, p < 0.01) and finally mortality results at the 20th day showed there is no significant difference between insecticides (p < 0.01).  相似文献   

13.
ABSTRACT

Rest-activity circadian rhythm (RAR) is a marker of the circadian timing system. Particular attention has been given to RAR characteristics in cancer diseases. Specifically, alterations of RAR parameters have been found, at different stages of clinical pathway, in breast cancer (BC) patients. No studies to date have analyzed RAR alterations in breast cancer survivors several years after the diagnosis. The aim of this study was to determine RAR by actigraphy in a population of BC survivors at 5 years after the primary diagnosis, and to compare their RAR characteristics with healthy controls. The study sample was 28 women: 15 BC survivors at 5 years from the primary diagnosis (BC-group) and 13 healthy controls (Ctrl-group), matched for age and body mass index. All participants have been monitored for 7 days by actigraphy to evaluate RAR. A statistically significant circadian rhythm (T = 24) was found in all 28 subjects (p < .001). The group analysis revealed a significant RAR both in BC- and Ctrl-group (p < .001). The acrophase was not different between the BC- and Ctrl-group (15:09 vs. 15:01 hr:min in BC- and Ctrl-group, respectively). In contrast, the MESOR (Midline Estimating Statistic of Rhythm) and the amplitude were lower in the BC-group with respect to the Ctrl-group. Indeed, the MESOR was 192.0 vs. 276.4 activity counts in BC- and Ctrl-group, respectively (p < .001), while the amplitude was 167.0 vs. 222.6 activity counts in BC- and Ctrl-group, respectively (p < .001). These results provide the first experimental evidence of alterations in RAR parameters in BC survivors at 5 years after the primary diagnosis. Larger studies with a prospective design are needed to assess the role of RAR in the quality of life and prognosis in BC survivors.  相似文献   

14.
Abstract

This study was conducted to investigate the effect of dietary conjugated linoleic acids (CLA) on growth performance and immune responses in broiler chicks. A total of 240 day-old Arbor Acre male broiler chicks were randomly allotted into four dietary treatments with different inclusion levels of CLA (0, 2.5, 5.0 or 10.0 g/kg) for six weeks. Growth performance, peripheral blood lymphocyte (PBL) proliferation, lysozyme activity, phagocytic activity (carbon clearance) and serum antibody titers against Newcastle disease virus (NDV) vaccine were examined. There were no significant differences in growth performance among treatments (p > 0.05). Chicks fed CLA diets produced more lysozyme activity in serum than the control group at 2 and 6 weeks of age (p < 0.05). Dietary CLA enhanced the PBL proliferation in response to concanavalin A (ConA) at the age of 42 d (p < 0.05). Phagocytic ability was also affected by dietary CLA and chicks fed CLA diets had faster carbon clearance rate (p < 0.05), but antibody titers to NDV was not influenced by dietary CLA. The results of the study suggested that dietary CLA could enhance innate and cellular immune response in broiler chicks, and not affect the growth performance.  相似文献   

15.
An improved understanding of the role of forage quality on the processes of particle dynamics and turnover is important for the development of healthier and cost-effective feeding strategies that aim at lowering the proportions of concentrates in the diets of cattle. The aim of this study was to evaluate the effects of feeding hays of different qualities on particle dynamics, digestion kinetics and turnover in the gastrointestinal tract (GIT). Three non-lactating, rumen fistulated Holstein cows were fed diets consisting exclusively of hay with either low quality [Group LH; 605 ± 12.4 g/kg neutral detergent fibre (NDF) and 63 ± 4.7 g/kg crude protein (CP)] or good quality (Group GH; 551 ± 20.1 g/kg NDF and 116 ± 3.6 g/kg CP). Data showed that in situ dry matter (DM) disappearance of the soluble fraction was greater for Group GH (p < 0.05). Feeding good quality hay also lowered the proportion of particles >1.18 mm particularly during the eating process (p < 0.05). Changes in the particle size occurring afterwards were greater for Group GH as well (p < 0.05); approximately 30% in the comminution in the particle size occurred postruminally. Feeding hay of good quality lowered DM content of solid rumen digesta (p < 0.05), accelerated (p < 0.05) the turnover rate of DM and NDF in the GIT and increased DM intake (p < 0.05). In conclusion, feeding forages of better quality significantly promoted degradation processes and kinetics in the GIT with positive effects on turnover rate of digesta and feed intake in Holstein cows.  相似文献   

16.
前期工作表明,内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)第4内含子中的27碱基 (nucleotide,nt)重复序列是27-nt microRNA的来源,并对eNOS具有重要的调节作用.为进一步探讨该内含子源性27-nt microRNA参与调节eNOS表达的分子机制及其在内皮细胞增殖中的可能作用,通过构建27-nt microRNA高表达质粒,用脂质体将该质粒转染人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVEC),Western blot和RT-PCR检测该细胞系中eNOS蛋白和mRNA表达情况以及胞核转录因子的表达改变,并观察HUVEC增殖的变化情况.结果发现:27-nt microRNA 高表达能降低eNOSmRNA的水平和蛋白质表达;同时对转录因子Sp1、Ap1的蛋白质表达也产生了不同程度的抑制作用;转染后细胞的生长速度比未转染的细胞明显减慢,尤其转染了27-nt microRNA的双倍长度突变体(pEGP-mut-54nt-mi)质粒的HUVEC,其生长倍增时间比正常对照组明显延长达49.4%.结果表明,27-nt microRNA明显抑制eNOS蛋白及其mRNA表达,同时 HUVEC增殖受到明显抑制,转录因子Sp1 和Ap1 在27-nt microRNA对eNOS的表达调节中起重要作用.实验提示,内含子源性microRNA与转录因子共同参与对内皮细胞增殖及其相关性基因的表达调节,可能是众多真核细胞中某些疾病相关性基因表达自我调节的重要机制之一.  相似文献   

17.
Heterologous protein expression levels in transgenic plants are of critical importance in the production of plant-made pharmaceuticals (PMPs). We studied a puroindoline b promoter and signal peptide (Tapur) driving human lysozyme expression in rice endosperm. The results demonstrated that human lysozyme expressed under the control of the Tapur cassette is seed-specific, readily extractable, active, and properly processed. Immuno-electron microscopy indicated that lysozyme expressed from this cassette is localized in protein bodies I and II in rice endosperm cells, demonstrating that this non-storage promoter and signal peptide can be used for targeting human lysozyme to rice protein bodies. We successfully employed a strategy to improve the expression of human lysozyme in transgenic rice grain by combining the Tapur cassette with our well established Gt1 expression system. The results demonstrated that when the two expression cassettes were combined, the expression level of human lysozyme increased from 5.24 ± 0.34 mg−1 g flour for the best single cassette line to 9.24 ± 0.06 mg−1 g flour in the best double cassette line, indicating an additive effect on expression of human lysozyme in rice grain.  相似文献   

18.
Abstract

Candida albicans is a leading cause of catheter-associated urinary tract infections and elimination of these biofilm-based infections without antifungal agents would constitute a significant medical advance. A novel urinary catheter prototype that utilizes on-demand surface deformation is effective at eliminating bacterial biofilms and here the broader applicability of this prototype to remove fungal biofilms has been demonstrated. C. albicans biofilms were debonded from prototypes by selectively inflating four additional intralumens surrounding the main lumen of the catheters to provide the necessary surface strain to remove the adhered biofilm. Deformable catheters eliminated significantly more biofilm than the controls (>90% eliminated vs 10% control; p < 0.001). Mechanical testing revealed that fungal biofilms have an elastic modulus of 45 ± 6.7 kPa with a fracture energy of 0.4–2 J m?2. This study underscores the potential of mechanical disruption as a materials design strategy to combat fungal device-associated infections.  相似文献   

19.
Proteins from the fresh roots of Stemona tuberosa (Stemonaceae) were extracted into 20 mM phosphate buffer, pH 7.2/0.1 M NaCl, precipitated with 90% saturation ammonium sulfate, and enriched by diethylaminoethanol (DEAE) cellulose. The protein eluted as a single main peak from the unbound fractions (ST-1), and appeared as a single band with superoxide dismutase (SOD) activity after native polyacrylamide gel electrophoresis (PAGE) resolution and zymogram development. ST-1 was classified as SOD due to its strong inhibition by HCN and H2O2. The amino acid sequence of three tryptic peptides of ST-1 matched with the SOD isozymes from Ananas comosus and Solanum lycopersicum. The SOD consisted of at least two heterologous protein subunits with molecular mass of 17.6 and 31.5 kD, respectively, and had an optimal SOD activity at pH 5 and over a temperature range of 0–50°C. MgCl2, MnCl2, and HgCl2 were strongly inhibitory at all concentrations tested. The SOD activity was completely negated in the presence of 0.5 mM SDS or 5 mM HgCl2. The relationship between riboflavin and nitroblue tetrazolium (NBT) on SOD activity was linear, giving K m and V max values of the purified SOD of 62.414 ± 0.015 M and 101.010 ± 0.022 µmol/min/mg protein for NBT and 27.389 ± 0.032 M and 38.167 ± 0.021 µmol/min/mg protein for riboflavin, respectively.  相似文献   

20.
A new diploid (2n?=?30) species, Rhaponticoides calabrica, is described from Calabria and Basilicata (southern Italy). This species differs from the closely related R. centaurium – an endemic of Apulia and northern Basilicata – by different flower colour (white in the former, purplish in the latter), width of membranous margin of phyllaries (1.8?±?0.4 mm vs 0.8?±?0.3 mm) and pappus length (6.8?±?0.9 mm vs 9.1?±?1.0 mm). The two species are completely allopatric and seem to have also different chromosome numbers.  相似文献   

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