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131.
Uniquely modified heptoses found in surface carbohydrates of bacterial pathogens are potential therapeutic targets against such pathogens. Our recent biochemical characterization of the GDP-6-deoxy-d-manno- and GDP-6-deoxy-d-altro-heptose biosynthesis pathways has provided the foundation for elucidation of the more complex l-gluco-heptose synthesis pathway of Campylobacter jejuni strain NCTC 11168. In this work we use GDP-4-keto,6-deoxy-d-lyxo-heptose as a surrogate substrate to characterize three enzymes predicted to be involved in this pathway: WcaGNCTC (also known as Cj1427), MlghB (Cj1430), and MlghC (Cj1428). We compare them with homologues involved in d-altro-heptose production: WcaG81176 (formerly WcaG), DdahB (Cjj1430), and DdahC (Cjj1427). We show that despite high levels of similarity, the enzymes have pathway-specific catalytic activities and substrate specificities. MlghB forms three products via C3 and C5 epimerization activities, whereas its DdahB homologue only had C3 epimerase activity along its cognate pathway. MlghC is specific for the double C3/C5 epimer generated by MlghB and produces l-gluco-heptose via stereospecific C4 reductase activity. In contrast, its homologue DdahC only uses the C3 epimer to yield d-altro-heptose via C4 reduction. Finally, we show that WcaGNCTC is not necessary for l-gluco-heptose synthesis and does not affect its production by MlghB and MlghC, in contrast to its homologue WcaG81176, that has regulatory activity on d-altro-heptose synthesis. These studies expand our fundamental understanding of heptose modification, provide new glycobiology tools to synthesize novel heptose derivatives with biomedical applications, and provide a foundation for the structure function analysis of these enzymes.  相似文献   
132.
Pseudoterranova decipiens larva is a rare cause of anisakiasis. Indeed, prior to the present study, there had been only 12 reports of larval P. decipiens infection in the Republic of Korea. In June 2011, an anisakid larva, 32.1 mm in length and 0.88 mm in width, and finally identified as the third stage larva of P. decipiens owing to the presence of an intestinal cecum but lacking ventricular appendage, was discovered in a 61-year-old woman during the course of endoscopy executed as a part of routine physical examinations. The patient had eaten raw a rockfish 13 hr prior to the endoscopy, but showed no symptoms of anisakiasis. This paper is the 13th report of P. decipiens infection in Korea.  相似文献   
133.
134.
The seed-feeding jewel bug, Agonosoma trilineatum (F.), is an introduced biological control agent for bellyache bush, Jatropha gossypiifolia L. To quantify the damage potential of this agent, shadehouse experiments were conducted with individual bellyache bush plants exposed to a range of jewel bug densities (0, 6 or 24 jewel bugs/plant). The level of abortion of both immature and mature seed capsules and impacts on seed weight and seed viability were recorded in an initial short-term study. The ability of the jewel bug to survive and cause sustained damage was then investigated by measuring seed production, the survival of adults and nymph density across three 6-month cycles. The level of seed capsule abortion caused by the jewel bug was significantly affected by the maturity status of capsules and the density of insects present. Immature capsules were most susceptible and capsule abortion increased with jewel bug density. Similarly, on average, the insects reduced the viability of bellyache bush seeds by 79% and 89% at low and high densities, respectively. However, sustaining jewel bug populations for prolonged periods proved difficult. Adult survival at the end of three 6-month cycles averaged 11% and associated reductions in viable seed production ranged between 55% and 77%. These results suggest that the jewel bug has the potential to reduce the number of viable seeds entering the soil seed bank provided populations can be established and maintained at sufficiently high densities.  相似文献   
135.
Chiu HC  Lin TL  Wang JT 《Helicobacter》2007,12(1):74-81
BACKGROUND: Pre-cleaning and soaking in glutaraldehyde is the necessary procedure to disinfect endoscopes. However, some chemical-solvent-tolerant bacteria may survive after incomplete endoscopic disinfection. The goal of this study was to identify glutaraldehyde resistance-related genes in Helicobacter pylori. MATERIALS AND METHODS: Lambda-Zap phagemid expression library of H. pylori strain NTUH-C1 was selected with 0.1% glutaraldehyde. The minimal inhibitory concentration (MIC) of glutaraldehyde-resistant DNA fragments of H. pylori NTUH-C1 strain were determined. Imp/OstA recombinant protein was expressed, purified, and used to generate anti-Imp/OstA polyclonal antibody. Imp/ostA knockout, deletion, and complementation strains were constructed. The function of Imp/OstA was monitored by organic solvent tolerance assay, antibiotics susceptibility test, and N-phenylnapthylamine assay. RESULTS: Using Imp/ostA polyclonal antibody against cell lysate of wild-type and imp/ostA mutant showed that it is not essential in H. pylori. Organic solvent tolerance assay demonstrated the role of Imp/ostA in n-hexane tolerance. MIC test showed that the mutation of imp/ostA was susceptible to hydrophobic and beta-lactam antibiotics. NPN assay demonstrated that the level of outer membrane permeability was increased by 50% in mutant strain comparing to wild-type strain (p < .001). CONCLUSIONS: We have identified an Imp/OstA protein that was associated with glutaraldehyde resistance in our clinical strain H. pylori NTUH-C1 by screening of lambda-Zap expression library. Disruption of this protein results in altering membrane permeability, sensitivity to organic solvent, and susceptibility to antibiotics.  相似文献   
136.
目的:探讨红金消结胶囊联合米非司酮治疗子宫肌瘤的疗效及对血清血管生成素-2(Ang-2)、表皮生长因子(EGF)、核因子-κBp65(NF-κBp65)水平的影响。方法:选择我院2017年5月至2018年5月接诊的103例子宫肌瘤患者,通过随机数表法将其分为观察组53例和对照组50例。对照组给予米非司酮治疗,观察组在对照组基础上联合红金消结胶囊治疗,两组患者在月经期间停药,均连续治疗3个月。比较两组的临床疗效、治疗前后血清Ang-2、EGF、NF-κBp65、卵泡雌激素(FSH)、促黄体生成素(LH)、雌二醇(E2)水平、子宫体积与瘤体情况的变化及不良反应的发生情况。结果:治疗后,观察组临床疗效总有效率为94.34%,显著高于对照组78%,P0.05),血清Ang-2、EGF、NF-κBp65、FSH、LH、E2水平均显著低于对照组(P0.05),子宫体积和子宫肌瘤体积均小于对照组(P0.05)。两组不良反应发生率比较差异无统计学意义(P0.05)。结论:红金消结胶囊联合米非司酮治疗子宫肌瘤的临床疗效显著优于单用米非司酮治疗,其可更显著改善患者性激素水平,缩小子宫和子宫肌瘤的体积,这可能与降低血清Ang-2、EGF、NF-κBp65水平有关。  相似文献   
137.
Photoacoustic endoscopy (PAE) is an emerging imaging modality, which offers a high imaging penetration and a high optical contrast in soft tissue. Most of the developed endoscopic photoacoustic sensing systems use miniaturized contact ultrasound transducers or complex optical approaches. In this work, a new fiber‐based detection technique using speckle analysis for contact‐free signal detection is presented. Phantom and ex vivo experiments are performed in transmission and reflection mode for proof of concept. In summary, the potential of the technique for endoscopic photoacoustic signal detection is demonstrated. The new technique might help in future to broaden the applications of PAE in imaging or guiding minimally invasive laser procedures.   相似文献   
138.
A forward imaging endoscope for optical coherence tomography angiography (OCTA) featuring a piezoelectric fiber scanner is presented. Imaging is performed with an optical coherence tomography (OCT) system incorporating an akinetic light source with a center wavelength of 1300 nm, bandwidth of 90 nm and A‐line rate of 173 kHz. The endoscope operates in contact mode to avoid motion artifacts, in particular, beneficial for OCTA measurements, and achieves a transversal resolution of 12 μm in air at a rigid probe size of 4 mm in diameter and 11.3 mm in length. A spiral scan pattern is generated at a scanning frequency of 360 Hz to sample a maximum field of view of 1.3 mm. OCT images of a human finger as well as visualization of microvasculature of the human palm are presented both in two and three dimensions. The combination of morphological tissue contrast with qualitative dynamic blood flow information within this endoscopic imaging approach potentially enables improved early diagnostic capabilities of internal organs for diseases such as bladder cancer.   相似文献   
139.
摘要 目的:研究复方谷氨酰胺以及双歧杆菌三联活菌胶囊联用治疗腹泻型肠易激综合征患者的临床疗效。方法:选择2016年1月~2020年2月安徽省濉溪县医院收治的81例腹泻型肠易激综合征患者,将其随机分为两组。对照组41例患者仅口服420 mg的双歧杆菌三联活菌胶囊,每天3次;观察组40例患者加用500 mg的复方谷氨酰胺,每天3次。检测两组治疗前后的血清内毒素、二胺氧化酶活性及D-乳酸水平;血清白介素-6(Interleukin -6,IL-6)、肿瘤坏死因子-α(Tumor necrosis factor alpha,TNF-α)、白介素-8(Interleukin -8,IL-8)、高敏C反应蛋白(High sensitive C reactive protein,hs-CRP)水平;血浆生长抑素和血管活性肠肽水平并比较治疗后临床疗效及治疗过程中不良反应的发生情况。结果:治疗后,观察组的有效率为97.5%,明显高于对照组(75.61%,P<0.05);两组的血清内毒素、二胺氧化酶活性及D-乳酸、IL-6、TNF-α、IL-8、hs-CRP水平、血浆生长抑素和血管活性肠肽水平均较治疗前明显降低(P<0.05),且观察组以上指标均明显低于对照组(P<0.05)。观察组治疗期间的有2例嗜睡、头晕、乏力不适,发生率为5.00 %,对照组有2例头晕,1例头痛、口干,发生率为7.32 %,两组对比无统计学意义(P>0.05)。结论:复方谷氨酰胺联合双歧杆菌三联活菌胶囊治疗腹泻型肠易激综合征患者的临床效果明显优于单用双歧杆菌三联活菌胶囊治疗,其可有效修复肠黏膜屏障损伤,可能与其减轻炎症反应并改善胃肠激素水平有关。  相似文献   
140.
An active biomimetic system by integrating kinesin motor, microtubule, and man-made biomimetic microcapsule has been constructed. Biomimetic microcapsules were fabricated by using the layer-by-layer technique and could serve as cargos in this active biomimetic system. Both of the hollow and filled capsules as cargos can be transported by kinesin motors along microtubules. It may help to create kinesin-powered complex hybrid micro- and nanodevices.  相似文献   
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