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1.
In order to establish a venom fingerprint and a peptide profile of the Lasiodora parahybana tarantula venom gland, we used conventional methods such as reversed phase liquid chromatography coupled to an electrospray-ionisation hybrid quadrupole time of flight mass spectrometer (LC/ESI-QqTOFMS), matrix-assisted laser desorption/ionization time-of-flight-MS (MALDI-TOFMS) and direct study of L. parahybana venom by nanospray-ionization QqTOFMS (nanoESI-QqTOFMS) and a new technology for the direct analysis of fresh tissues using MALDI-TOFMS. The analysis of the crude venom allowed the characterization of specific juvenile and adult biomarkers. In situ MALDI analysis of L. parahybana venom gland sections revealed different peptide expression levels all along the gland and non-processed peptide precursors, demonstrating the power of the method for the dynamic investigation of peptide evolution in the venom gland of spiders.  相似文献   
2.
BACKGROUND: Acne is a multifactorial disease exhibiting distinct clinical presentations. Among them, the catamenial type is a matter of concern for young women. Some oral contraceptives may help without, however, clearing the skin condition. AIM: The present open study aimed at evaluating the effect of overnight applications of a paste made of petrolatum,15% zinc oxide and 0.25% miconazole nitrate. METHOD: The split-face trial was conducted in 35 women. A non-medicated cream was used as control. Clinical evaluations and biometrological assessments on cyanoacrylate follicular biopsies were performed monthly for 3 months. Comedometry and the density in autofluorescent follicular casts were used as analytical parameters. In addition, the five most severe cases at inclusion were tested at the completion of the study for follicular bacterial viability using dual flow cytometry. RESULTS: Compared with baseline and to the control hemi-face, the medicated paste brought significant improvement of acne. The number of papules and their redness were reduced beginning with the first treatment phase. A reduction in the follicular fluorescence was yielded beginning with the second treatment phase. The ratios between injured and dead bacteria, on the one hand, and live bacteria, on the other hand were significantly increased at completion of the study. CONCLUSION: A miconazole paste applied for 1 week at the end of the ovarian cycle has a beneficial effect on catamenial acne.  相似文献   
3.
The hypothesis that the release of vasopressin-associated neurophysin (hNpI) or oxytocin-associated neurophysin (hNpII) is modified by a course of electroconvulsive therapy (ECT) was tested by the measurement of serum neurophysins before and after the first and last ECTs given to 17 unipolar depressed patients. Neither basal nor ECT-induced neurophysin release changed between the first and last ECTs. Data from the present study were combined with data from a previous published study to provide a sample of 29 unipolar depressed patients. In this extended sample, the release of hNpII after the first ECT was significantly correlated with improvement in symptoms of depression over a course of ECT as measured by the Hamilton Rating Scale for Depression and the Montgomery-Asberg Depression Rating Scale.  相似文献   
4.
Blood lactate response to overtraining in male endurance athletes   总被引:2,自引:0,他引:2  
Many physiological markers vary similarly during training and overtraining. This is the case for the blood lactate concentration ([La]b), since a right shift of the lactate curve is to be expected in both conditions. We examined the possibility of separating the changes in training from those of overtraining by dividing [La]b by the rating of perceived exertion ([La]b/RPE) or by converting [La]b into a percentage of the peak blood lactate concentration ([La]b,peak). Ten experienced endurance athletes increased their usual amount of training by 100% within 4 weeks. An incremental test and a time trial were performed before (baseline) and after this period of overtraining, and after 2 weeks of recovery (REC). The [La]b and RPE were measured during the recovery of each stage of the incremental test. We diagnosed overtraining in seven athletes, using both physiological and psychological criteria. We found a decrease in mean [La]b,peak from baseline to REC [9.64 (SD 1.17), 8.16 (SD 1.31) and 7.69 (SD 1.84) mmol · l−1, for the three tests, respectively; P < 0.05] and a right shift of the lactate curve. Above 90% of maximal aerobic speed (MAS) there was a decrease of mean [La]b/RPE from baseline to REC [at 100% of MAS of 105.41 (SD 17.48), 84.61 (SD 12.56) and 81.03 (SD 22.64) arbitrary units, in the three tests, respectively; P < 0.05), but no difference in RPE, its variability accounting for less than 25% of the variability of [La]b/RPE (r=0.49). Consequently, [La]b/RPE provides little additional information compared to [La]b alone. Expressing [La]b as a %[La]b,peak resulted in a suppression of the right shift of the lactate curve, suggesting it was primarily the consequence of a decreased production of lactate by the muscle. Since the right shift of the curve induced by optimal training is a result of improved lactate utilization, the main difference between the two conditions is the decrease of [La]b,peak during overtraining. We propose retaining it as a marker of overtraining for long duration events, and repeating its measurement after a sufficient period of rest to make the distinction with overreaching. Accepted: 26 September 2000  相似文献   
5.
A prospective survey was conducted on 862 Enterobacteriaceae isolates with reduced susceptibility to carbapenems. The Carba NP test, UV spectrophotometry, and a DNA microarray were used to detect carbapenemase producers, and the results were compared to those from PCR and sequencing. The 172 carbapenemase producers were detected using the Carba NP test and UV spectrophotometry, whereas the DNA microarray failed to detect IMI producers. The use of the Carba NP test as a first screening, followed by the use of molecular techniques, has been determined to be an efficient strategy for identifying carbapenemase-producing Enterobacteriaceae.  相似文献   
6.
Purpose: We created an epilepsy patient database that can be accessed via the Internet by neurologists from anywhere in the world. The database was designed to enroll and follow large cohorts of patients with specific epilepsy syndromes, and to facilitate recruitment of patients for investigator‐initiated clinical trials. Methods: The EpiNet database records physician‐derived information regarding seizure type and frequency, epilepsy syndrome, etiology, drug history, and investigations. It can be accessed from any country by approved investigators via a secure, password‐protected Website. All data are encrypted. The database is for both research and clinical purposes. Investigators were invited to register any patient with epilepsy, but were particularly encouraged to register patients when uncertain of the optimal management. Participation required approval from investigators’ ethics committees and institutional review boards, and all patients or their caregiver provided written informed consent. Patients were not enrolled in clinical trials in this pilot study. Key Findings: The international pilot study recruited patients from September 2010 to November 2011. Sixty‐four investigators or research assistants from 25 centers in 13 countries registered 1,050 patients. Patients with a wide range of epilepsy syndromes and etiologies were registered. Patients’ ages ranged from 2 weeks to 90 years. Significance: The Website was successfully used by doctors working in different health systems. The pilot study confirmed that this low‐cost, collaborative approach to research has great potential. Large, multicenter cohort studies will commence in 2012, and randomized clinical trials are being planned. All epileptologists are invited to join this project.  相似文献   
7.
BACKGROUND Liver transplantation(LT) is the best treatment for patients with liver cancer or end stage cirrhosis, but it is still associated with a significant mortality. Therefore identifying factors associated with mortality could help improve patient management. The impact of iron metabolism, which could be a relevant therapeutic target, yield discrepant results in this setting. Previous studies suggest that increased serum ferritin is associated with higher mortality.Surprisingly iron deficiency which is a well described risk factor in critically ill patients has not been considered.AIM To assess the impact of pre-transplant iron metabolism parameters on posttransplant survival.METHODS From 2001 to 2011, 553 patients who underwent LT with iron metabolism parameters available at LT evaluation were included. Data were prospectively recorded at the time of evaluation and at the time of LT regarding donor and recipient. Serum ferritin(SF) and transferrin saturation(TS) were studied as continuous and categorical variable. Cox regression analysis was used to determine mortality risks factors. Follow-up data were obtained from the local and national database regarding causes of death.RESULTS At the end of a 95-mo median follow-up, 196 patients were dead, 38 of them because of infections. In multivariate analysis, overall mortality was significantly associated with TS 75% [HR: 1.73(1.14; 2.63)], SF 100 μg/L [HR: 1.62(1.12;2.35)], hepatocellular carcinoma [HR: 1.58(1.15; 2.26)], estimated glomerular filtration rate(CKD EPI Cystatin C) [HR: 0.99(0.98; 0.99)], and packed red blood cell transfusion [HR: 1.05(1.03; 1.08)]. Kaplan Meier curves show that patients with low SF( 100 μg/L) or high SF( 400 μg/L) have lower survival rates at 36 mo than patients with normal SF(P = 0.008 and P = 0.016 respectively). Patients with TS higher than 75% had higher mortality at 12 mo(91.4% ± 1.4% vs 84.6% ±3.1%, P = 0.039). TS 75% was significantly associated with infection related death [HR: 3.06(1.13; 8.23)].CONCLUSION Our results show that iron metabolism imbalance(either deficiency or overload)is associated with post-transplant overall and infectious mortality. Impact of iron supplementation or depletion should be assessed in prospective study.  相似文献   
8.

Introduction

POEMS syndrome (polyneuropathy, organomegaly, endocrynopathy, M-protein, and skin changes) is a rare multisystem disease associated with plasma cell dyscrasia. The efficacy of autologous peripheral blood stem cell transplantation (auto-PBSCT) reported in case series has been mainly based on hematologic criteria and clinical recovery of peripheral neuropathy dysfunctions but has not been specifically evaluated. This retrospective study aimed to analyze the efficacy of auto-PBSCT on disability and electrophysiological patterns in patients with POEMS syndrome.

Methods

Five patients presenting with POEMS syndrome received auto-PBSCT. Disability was evaluated before treatment and at 6 and 12 months using the Overall Neuropathy Limitation Scale (ONLS) and MRC sumscore of 28 muscles. Nerve conduction studies were performed before and one year after treatment, on median, ulnar, fibular and tibial nerves.

Results

Mean age was 60.6 years (49–70). Disease duration between first symptoms and auto-PBSCT was 15.4 months (2–33). Before auto-PBSCT, mean ONLS score was 4.2 (1–10) and mean MRC sumscore 115.8/140 (74–140). At M6, mean ONLS score decreased and mean MRC sumscore increased; both were improved in all patients at M12: mean ONLS score 3 (range 0–8) at M6 and 2.2 (range 0–7) at M12; mean MRC sumscore 118/140 (77–140) at M6 and 122.4/140 (80–140) at M12. Significant recovery in electrophysiological patterns was observed in all patients on ulnar and median nerves: before-after treatment differences were observed for motor conduction velocities (34.41 vs. 45.47 m/s; P < 0.001), distal CMAP amplitudes (5.04 vs. 5.96 mV; P = 0.004), and sensory conduction velocities (43.20 vs. 49.20 m/s; P = 0.001). Distal CMAP amplitude remained low in fibular and tibial nerves (0.41 vs. 0.17 mV).

Conclusions

Clinical and electrophysiological improvement is obvious in POEMS syndrome peripheral neuropathy within one year after treatment with auto-PBSCT, undoubtedly resulting from extensive remyelinisation and axonal regeneration. Further studies are required to examine long-term outcome in patients with POEMS syndrome given auto-PBSCT.  相似文献   
9.
(1)O(2) (singlet oxygen) is a reactive O(2) species produced from triplet excited chlorophylls in the chloroplasts, especially when plants are exposed to excess light energy. Similarly to other active O(2) species, (1)O(2) has a dual effect: It is toxic, causing oxidation of biomolecules, and it can act as a signal molecule that leads to cell death or to acclimation. Carotenoids are considered to be the main (1)O(2) quenchers in chloroplasts, and we show here that light stress induces the oxidation of the carotenoid β-carotene in Arabidopsis plants, leading to the accumulation of different volatile derivatives. One such compound, β-cyclocitral, was found to induce changes in the expression of a large set of genes that have been identified as (1)O(2) responsive genes. In contrast, β-cyclocitral had little effect on the expression of H(2)O(2) gene markers. β-Cyclocitral-induced reprogramming of gene expression was associated with an increased tolerance to photooxidative stress. The results indicate that β-cyclocitral is a stress signal produced in high light that is able to induce defense mechanisms and represents a likely messenger involved in the (1)O(2) signaling pathway in plants.  相似文献   
10.
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