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41.
BackgroundOur previous studies showed increased angiotensin I-converting enzyme (ACE) activity in chronic schizophrenia patients compared with healthy control (HC) volunteers, and the relevance of combining ACE genotype and activity for predicting schizophrenia was suggested.MethodsACE activity was measured in plasma of ACE insertion/deletion (I/D) genotyped HC volunteers (n = 53) and antipsychotic-naïve first-episode psychosis (FEP) patients (n = 45) assessed at baseline (FEB-B) and also after 2 months (FEP-2M) of treatment with the atypical antipsychotic risperidone.ResultsACE activity measurements showed significant differences among HC, FEP-B, and FEP-2M groups (F = 5.356, df = 2, P = .005) as well as between HC and FEP-2M (post-hoc Tukey’s multiple comparisons test, P = .004). No correlation was observed for ACE activity increases and symptom severity reductions in FEP as assessed by total Positive and Negative Syndrome Scale (r = −0.131, P = .434). FEP subgrouped by ACE I/D genotype showed significant ACE activity increases, mainly in the DD genotype subgroup. No correlation between ACE activity and age was observed in FEP or HC groups separately (r = 0.210, P = .392), but ACE activity level differences observed between these groups were influenced by age.ConclusionsThe importance of measuring the ACE activity in blood plasma, associated with ACE I/D genotyping to support the follow-up of FEP patients, did not show correlation with general symptom amelioration in the present study. However, new insights into the influence of age and I/D genotype for ACE activity changes in FEP individuals upon treatment was demonstrated.  相似文献   
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43.
Starfish can regenerate entire arms following their loss by both autotomic and traumatic amputation. Although the overall regenerative process has been studied several times in different asteroid species, there is still a considerable gap of knowledge as far as the detailed aspects of the repair phase at tissue and cellular level are concerned, particularly in post‐traumatic regeneration. The present work is focused on the arm regeneration model in the Mediterranean red starfish Echinaster sepositus; to describe the early cellular mechanisms of arm regeneration following traumatic amputation, different microscopy techniques were employed. In E. sepositus, the repair phase was characterized by prompt wound healing by a syncytial network of phagocytes and re‐epithelialisation followed by a localized subepidermal oedematous area formation. Scattered and apparently undifferentiated cells, intermixed with numerous phagocytes, were frequently found in the wound area during these first stages of regeneration and extensive dedifferentiation phenomena were seen at the level of the stump, particularly in the muscle bundles. A true localized blastema did not form. Our results confirm that regeneration in asteroids mainly relies on morphallactic processes, consisting in extensive rearrangement of the existing tissues which contribute to the new tissues through cell dedifferentiation, redifferentiation, and/or migration.  相似文献   
44.

Purpose

The treatment of urinary tract infections (UTI) with antibiotics is commonly used, but recurrence and antibiotic resistance have been growing and concerning clinicians. We studied whether the rapid onset of a protective biofilm may be responsible for the lack of effectiveness of antibiotics against selected bacteria.

Materials and Methods

Two established uropathogenic Escherichia coli strains, UTI89 and CFT073, and two Pseudomonas aeruginosa strains, PA01 and Boston-41501, were studied to establish a reliable biofilm formation process. Bacterial growth (BG) was determined by optical density at 600 nm (OD 600) using a spectrophotometer, while biofilm formation (BF) using crystal violet staining was measured at OD 550. Next, these bacterial strains were treated with clinically relevant antibiotics, ciprofloxacin HCl (200 ng/mL and 2 μg/mL), nitrofurantoin (20 μg/mL and 40 μg/mL) and ampicillin (50 μg/mL) at time points of 0 (T0) or after 6 hours of culture (T6). All measurements, including controls (bacteria -1% DMSO), were done in triplicates and repeated three times for consistency.

Results

The tested antibiotics effectively inhibited both BG and BF when administered at T0 for UPEC strains, but not when the antibiotic administration started 6 hours later. For Pseudomonas strains, only Ciprofloxacin was able to significantly inhibit bacterial growth at T0 but only at the higher concentration of 2 μg/mL for T6.

Conclusion

When established UPEC and Pseudomonas bacteria were allowed to culture for 6 hours before initialization of treatment, the therapeutic effect of selected antibiotics was greatly suppressed when compared to immediate treatment, probably as a result of the protective nature of the biofilm.  相似文献   
45.
OBJECTIVE: The RELIEF investigation was a 48-week, multicenter, international study comprising 2 phases. Results from the first phase, a 24-week open-label cohort study that evaluated the safety and efficacy of leflunomide, as well as predisposing factors to treatment response, are reported here. METHODS: Patients received leflunomide 100 mg once daily for 3 days, followed by 20 mg once daily thereafter. All adverse events were documented. Efficacy variables were the European League Against Rheumatism (EULAR) response criteria using the Disease Activity Score (DAS 28) responder rate and the response rate according to American College of Rheumatology (ACR) criteria. At Week 24, baseline data were analyzed to determine predictive factors for treatment response. RESULTS: A total of 969 patients were entered in the trial. No adverse events that have not previously been seen with leflunomide were reported. Among 968 evaluable patients, 673 (69.6%) completed 24 weeks of treatment and were responders according to DAS 28 response rate, and 587 (60.6%) completed 24 weeks of treatment and were responders according to ACR 20%. Thus, there was a high correlation between the EULAR and ACR criteria in determining treatment response. In addition, 240 (24.8%) patients had a low DAS 28 (< or = 3.2) and 123 (12.7%) patients fulfilled the disease remission criteria (DAS 28 < 2.6) at the end of the study. CONCLUSION: This study demonstrates that leflunomide is well tolerated, with a safety profile similar to that seen previously in Phase III studies, and confirms the efficacy of leflunomide across a range of patient categories.  相似文献   
46.
BackgroundColonoscopy demands a considerable amount of resources, and little is known about its diagnostic yield among inpatients.AimsTo assess indications, diagnostic yield and findings of colonoscopy for inpatients, and to identify risk factors for relevant findings and cancer.MethodsMulticentre, prospective, observational study including 12 hospitals. Consecutive adult inpatients undergoing colonoscopy were evaluated from February through November 2019.Results1,302 inpatients underwent colonoscopy. Diagnostic yield for relevant findings and cancer was 586 (45%) and 112 (8.6%), respectively. Adequate colon cleansing was achieved in 896 (68.8%) patients. Split-dose/same-day regimen was adopted in 847 (65%) patients. Factors associated to relevant findings were age ≥70 years (RR 1.32), male gender (RR 1.11), blood loss (RR 1.22) and adequate cleansing (RR 1.63). Age ≥70 years (RR 2.08), no previous colonoscopy (RR 2.69) and split-dose/same-day regimen (RR 1.59) significantly increased cancer detection. Implementing adequate cleansing and split-dose/same-day regimen in all patients would increase the diagnostic yield for any relevant findings and cancer from 43% to 70% and from 6% to 10%, respectively.ConclusionRelevant colorectal diseases and cancer were frequent among inpatients. Factors associated with detection of relevant findings were identified. Adequate colon cleansing and split-dose/same-day regimen significantly increased colonoscopy diagnostic yield.  相似文献   
47.
48.
OBJECTIVES:Experimental studies on sepsis have demonstrated that ethyl pyruvate is endowed with antioxidant and anti-inflammatory properties. This study aimed to investigate the effects of ethyl pyruvate on leukocyte-endothelial interactions in the mesenteric microcirculation in a live Escherichia coli-induced sepsis model in rats.METHODS:Male Wistar rats were administered an intravenous suspension of E. coli bacteria or were subjected to a sham procedure. Three hours after bacterial infusion, the rats were randomized into the following groups: a control group without treatment, a group treated with lactated Ringer''s solution (4 mL/kg, i.v.), and a group treated with lactated Ringer''s solution (4 mL/kg, i.v.) plus ethyl pyruvate (50 mg/kg). At 24 h after bacterial infusion, leukocyte-endothelial interactions were investigated using intravital microscopy, and the expression of P-selectin and intercellular adhesion molecule-1 was evaluated via immunohistochemistry. White blood cell and platelet counts were also determined at baseline and 3 h and 24 h after E. coli inoculation.RESULTS:The non-treated and lactated Ringer''s solution-treated groups exhibited increases in the numbers of rolling leukocytes (∼2.5-fold increase), adherent cells (∼3.0-fold), and migrated cells (∼3.5-fold) compared with the sham group. In contrast, treatment with Ringer''s ethyl pyruvate solution reduced the numbers of rolling, adherent and migrated leukocytes to the levels observed in the sham group. Additionally, the expression of P-selectin and intercellular adhesion molecule-1 was significantly increased on mesenteric microvessels in the non-treated group compared with the sham group (p<0.001). The expression of both adhesion molecules was reduced in the other groups, with ethyl pyruvate being more effective than lactated Ringer''s solution. Infusion of bacteria caused significant leukopenia (3 h), followed by leukocytosis with granulocytosis (24 h). There was also an intense and progressive reduction in the number of platelets. However, no differences were observed after treatment with the different solutions.CONCLUSIONS:The presented data suggest that ethyl pyruvate efficiently reduces the inflammatory response in the mesenteric microcirculation in an experimental model of sepsis induced by live E. coli and is associated, at least in part, with down-regulation of P-selectin and intercellular adhesion molecule-1.  相似文献   
49.
Pantothenamides inhibit blood-stage Plasmodium falciparum with potencies (50% inhibitory concentration [IC50], ∼20 nM) similar to that of chloroquine. They target processes dependent on pantothenate, a precursor of the essential metabolic cofactor coenzyme A. However, their antiplasmodial activity is reduced due to degradation by serum pantetheinase. Minor modification of the pantothenamide structure led to the identification of α-methyl-N-phenethyl-pantothenamide, a pantothenamide resistant to degradation, with excellent antiplasmodial activity (IC50, 52 ± 6 nM), target specificity, and low toxicity.  相似文献   
50.

Background

Capsule endoscopy has been proposed as an alternative to fibreoptic endoscopy for oesophageal varices evaluation in cirrhotics. However, it shows only moderate sensitivity compared to fibreoptic endoscopy.

Aim

To compare post-meal capsule endoscopy to fibreoptic endoscopy, based on the hypothesis that meal-induced increase of portal pressure can enhance its sensitivity.

Methods

Twenty-five patients were submitted to fibreoptic endoscopy and, after a standard meal, capsule endoscopy.

Results

Post-meal capsule endoscopy detected varices in the 18 patients in whom fibreoptic endoscopy detected varices plus 3 more subjects (sensitivity 100%, specificity 70%); large varices in the 4 patients in whom fibreoptic endoscopy graded varices as large, plus 5 more subjects; red markers in the 5 patients in whom fibreoptic endoscopy detected red markers, plus 3 more subjects. High-risk varices were identified in 11 patients by post-meal capsule endoscopy and in 10 by fibreoptic endoscopy (sensitivity 100%, specificity 93.8%).

Conclusions

Post-meal capsule endoscopy identified more varices, large varices and red markers than fibreoptic endoscopy. The two methods detected similar proportions of high-risk varices. These data suggest that a standard meal can enhance the sensitivity of capsule endoscopy in the detection and grading of oesophageal varices in cirrhotics.  相似文献   
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