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Veronica peregrina has a wide range of types of constituents with various pharmacological properties. Here in this study, we isolated protocatechuic acid (PCA) from V. peregrina and examined PCAs effects on the lifespan and stress tolerance using Caenorhabditis elegans model system. We found that lifespan of wild-type worms was significantly lengthened in the presence of PCA in a dose dependent manner. PCA also elevated tolerance of worms against osmotic, heat shock, and oxidative stress. We also demonstrated antioxidant capacity of PCA by checking intracellular reactive oxygen species level and antioxidant enzyme activities such as catalase and superoxide dismutase. We further investigated several factors including pharyngeal pumping rate and progeny production that might influence prolonged lifespan and enhanced stress tolerance by PCA. Interestingly, both factors were significantly reduced after PCA exposure, indicating PCA exerts longevity activity by shifting food intake and reproduction at least in part. In addition, PCA-treated aged worms showed increased body movement compared to untreated controls suggesting PCA could enhance healthspan as well as lifespan.  相似文献   
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Development of stable protein formulations needs intimate knowledge of the proteins?? physicochemical properties. More specifically, understanding the mechanisms of protein degradation is important in designing and evaluating protein formulations. This review describes briefly the different types of interactions of the major protein degradation pathways. The analytical methods to detect protein degradation are included, along with generalized strategies to suppress protein instability with relevant excipients. With an appreciation of the current practices for stable formulations, the development process will be facilitated in a more efficient way.  相似文献   
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Chin tuck has been has been widely used to prevent aspiration in the patients with dysphagia. This study was performed to investigate the effectiveness and the degree of optimal neck flexion of chin tuck. Ninety-seven patients who showed aspiration in the videofluoroscopic swallow study (VFSS). Participants were grouped into the effective (patients who showed effect with chin tuck) and ineffective group (those who did not show effect with chin tuck). VFSS was performed in neutral and chin tuck position and findings were compared between the groups. Severity of aspiration was assessed by the point penetration-aspiration scale. Duration of dysphagic symptoms, history of tracheostomy, and other possible contributing factors were also compared. Neck flexion angle was measured to find appropriate posture in which aspiration was prevented with chin tuck. Aspiration was reduced or eliminated in only 19 patients (19.6 %) with chin tuck. Oral transit time, pharyngeal delayed time and pharyngeal transit time were significantly shortened in both groups (p < 0.05), but the difference between the groups was not significant. Female sex and absence of residue in pyriform sinus favored the effect of chin tuck (p < 0.05). At least 17.5° of neck flexion was required to achieve an effect with chin tuck. The effectiveness of chin tuck was less than anticipated. Patients without residue in pyriform sinus were more likely to benefit from chin tuck. Sufficient neck flexion was important in chin tuck to prevent aspiration.  相似文献   
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Spontaneous intramural esophageal dissection is a rare disorder characterized by a lengthy laceration between the mucosal and submucosal layers of the esophageal wall, without perforation. The majority of previously reported cases of spontaneous intramural esophageal dissection were partial, and the circumferential type of intramural esophageal dissection has not been reported previously. Most spontaneous intramural esophageal dissection responds to conservative management, and usually it dose not lapse into a long protracted course of dealing with sequelae. We report an unusual case of circumferential intramural esophageal dissection, in which initial conservative management failed to alleviate the patient's dysphagia, necessitating the use of several endoscopic treatments, including incision of the septum between the false and true lumens, transection of the true esophageal wall, balloon dilatation, and metal stent insertion.  相似文献   
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