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71.

Rationale

There is increasing evidence to suggest the possible efficacy of Crocus sativus (saffron) in the management of Alzheimer’s disease (AD).

Objective

The purpose of the present investigation was to assess the efficacy of C. sativus in the treatment of patients with mild-to-moderate AD.

Methods

Fifty-four Persian-speaking adults 55 years of age or older who were living in the community were eligible to participate in a 22-week, double-blind study of parallel groups of patients with AD. The main efficacy measures were the change in the Alzheimer’s Disease Assessment Scale—cognitive subscale and Clinical Dementia Rating Scale—Sums of Boxes scores compared with baseline. Adverse events (AEs) were systematically recorded. Participants were randomly assigned to receive a capsule saffron 30 mg/day (15 mg twice per day) or donepezil 10 mg/day (5 mg twice per day).

Results

Saffron at this dose was found to be effective similar to donepezil in the treatment of mild-to-moderate AD after 22 weeks. The frequency of AEs was similar between saffron extract and donepezil groups with the exception of vomiting, which occurred significantly more frequently in the donepezil group.

Conclusion

This phase II study provides preliminary evidence of a possible therapeutic effect of saffron extract in the treatment of patients with mild-to-moderate Alzheimer’s disease. This trial is registered with the Iranian Clinical Trials Registry (IRCT138711051556N1).  相似文献   
72.
BACKGROUND: Scaling and root planing in combination with oral hygiene monitoring are still considered the therapeutic standards for periodontitis. Although this treatment concept customarily results in satisfactory clinical improvements, treatment outcome may become less favorable predominantly when full access to periodontal defects is compromised, thereby leaving accretions behind. The purpose of this study was to investigate, over a 9-month period, the clinical benefits of a treatment strategy for chronic periodontitis based on a combination of sequential scaling and root planing and subgingival chlorhexidine varnish administration. METHODS: This randomized controlled, single blind, parallel trial included 26 volunteers with chronic periodontitis. The control group received oral hygiene instructions and was scaled and root planed in two sessions. The test group received the same instructions and treatment; however, all pockets were additionally disinfected using a highly concentrated chlorhexidine varnish. Clinical response parameters were recorded at baseline and at 1, 3, 6, and 9 months. The impact of the initial strategy on the decision-making process for supplementary therapy at 9 months was investigated based on treatment decisions made by five independent clinicians. RESULTS: Both treatment strategies showed significant reductions in probing depth and gains in clinical attachment at study termination in comparison with baseline (P<0.001). However, combination therapy resulted in a significant additional pocket reduction of 0.62 mm (P<0.001). Initially deep pockets (>or=7 mm) around multirooted teeth seemed to benefit most from the combination strategy, resulting in an additive pocket reduction of 1.06 mm (P=0.009) and a clinical attachment gain of 0.54 mm (P=0.048) in comparison to scaling and root planing alone. A trend toward a reduction of surgical treatment needs following the varnish-implemented strategy was found (P=0.076). CONCLUSION: These findings suggest that the outcome of initial periodontal therapy may benefit from the adjunctive subgingival administration of a highly concentrated chlorhexidine varnish.  相似文献   
73.
Several techniques exist for the surgical placement of dental implants. The aim of this study was to assess systematically, the efficacy of these protocols by the evidence-based perspective. Five best-case studies involving 607 early/immediately loaded implants and 300 conventionally loaded implants were identified by examining the available literature and rigorous inclusion/exclusion criteria. Overall analyses demonstrated a 98.4 percent success rate for the early/immediate procedure and a 95.3 percent for the conventional protocol. Success rates in the articles reviewed were based on implant survival over a follow-up period of between one to two years. A meta-analysis was generated to evaluate the presented evidence and to aid in decision-making. Despite its common implementation, this technique presents many caveats, among which publication bias is one of the most common. To investigate the possible presence of publication bias, a funnel plot analysis complemented several statistical tests. By means of the systematic investigation of dental implants, the authors' results confirm the presence of publication bias in implant dentistry literature, which strongly suggests that clinicians ought not base their decisions solely on the results presented by a few published studies. Rather, it is recommended that clinicians cautiously draw conclusions and seek studies that present accountable and clinically relevant results. Furthermore, it is suggested that clinicians attend seminars to learn of the effective advances in evidence-based dentistry, so as to develop the ability to easily detect inadequate literature due to attempted correlation with the most current research. It is also recommended that additional research is necessary to analyze which fields of research are more prone to bias, thus forewarning clinicians before formulating clinical conclusions.  相似文献   
74.
During last decades, diphtheria has remained as a serious disease that still outbreaks and can occur worldwide. Recently, new vaccine delivery systems have been developed by using the biodegradable and biocompatible polymers such as alginate. Alginate nanoparticles as a carrier with adjuvant and prolong release properties that enhance the immunogenicity of vaccines. In this study diphtheria toxoid loaded nanoparticles were prepared by ionic gelation technique and characterized with respect to size, zeta potential, morphology, encapsulation efficiency, release profile, and immunogenicity. Appropriate parameters (calcium chloride and sodium alginate concentration, homogenization rate and homogenization time) redounded to the formation of suitable nanoparticles with a mean diameter of 70±0.5 nm. The loading studies of the nanoparticles resulted in high loading capacities (>90%) and subsequent release studies showed prolong profile. The stability and antigenicity of toxoid were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and ouchterlony test and proved that the encapsulation process did not affect the antigenic integrity and activity. Guinea pigs immunized with the diphtheria toxoid-loaded alginate nanoparticles showed highest humoral immune response than conventional vaccine. It is concluded that, with regard to the desirable properties of nanoparticles and high immunogenicity, alginate nanoparticles could be considered as a new promising vaccine delivery and adjuvant system.  相似文献   
75.

Purpose

The study aims to identify the association between the baseline retinal vascular calibre and visual outcome of patients with diabetic macular oedema (DMO) treated with intravitreal ranibizumab.

Methods

The 1-M field (as defined in the ETDRS study) of the digital colour fundus photographs of DMO patients who had been treated primarily with ranibizumab in a clinical trial was assessed. Of the 84 patients, 25 had gradable retinal photographs that could be subjected to analyses by the Interactive Vessel Analysis (IVAN) software at baseline. The average retinal vascular calibre of the six largest venules (CRVE) and the six largest arterioles (CRAE) in the peripapillary area (0.5 and 1 disc diameter from the optic disc margin) was measured. The relationship between CRVE and CRAE at baseline and the change in visual acuity at month 12 was assessed using the Mann–Whitney U test.

Results

Ten eyes from 10 patients who had shown an improvement of ≥2 lines of best corrected visual acuity (BCVA) at month 12 had a wider baseline CRVE (248.3±24.5 μm) compared with the 15 eyes from 15 patients who did not show the improvement of ≥2 lines (226.6±44.8 μm, P<0.05). The baseline CRAE did not differ significantly in these patients (156.1±22.7 vs 142±17.5 μm, P=0.17).

Conclusions

A wider baseline retinal venular calibre may be a predictor of better visual outcome in DMO eyes treated with ranibizumab. Further prospective studies with a larger sample size and a broader range of disease severity and visual acuity are needed to confirm this finding.  相似文献   
76.
Leishmania major is the causative agent of zoonotic cutaneous leishmaniasis (ZCL) in which gerbils are the reservoir host. ZCL is of great public health importance in Iran. In the current investigation, nested polymerase chain reaction (PCR) protocols were used to amplify a region of the ribosomal RNA amplicon of Leishmania (ITS1-5.8S rRNA gene). The PCR assays detected L. major in three rodent species: Rhombomis opimus, Meriones lybicus and, for first time, Meriones persicus. L. major parasite was found in Natanz, Isfahan Province in the center of Iran in a focus of rural zoonotic cutaneous leishmaniasis. Four L. major infections were detected in R. opimus species, three in M. Lybicus, and two in M. persicus. All nine rodent infections of L. major were found to be the same haplotype based on the PCR detection and sequencing of parasite ITS-ribosomal DNA gene. In addition, also for the first time, the nested PCR assays detected Leishmania tropica only in one M. persicus. Allied to studies in country, the new findings mean that past conclusions about the reservoir of L. major in Iran must be treated with caution. Finding two Leishmania species in different rodent species as reservoir in Iran, therefore, careful molecular eco-epidemiological investigations will be an essential part of modeling the roles of different gerbil species in maintaining and spreading ZCL foci. An erratum to this article can be found at  相似文献   
77.
Endometrial stromal sarcomas (ESS) are the second most common uterine sarcomas. Endometrial stromal sarcomas account for 0.25% of all uterine malignancies. Uterine sarcomas most often affect postmenopausal women. The aim of this retrospective study was to review the experience in the treatment and clinical outcome of low grade malignant endometrial stromal sarcoma. Seventeen patients with histologically proven low grade ESS in department of Gynecologic Oncology of the Vali-e-Asr Hospital, Tehran-Iran, between 1999 and 2008 were included in the analysis. Demographics, pathology, treatment, time to recurrence, salvage therapy and survival information was collected. The median age of our patients was 45.35 ± 6.8 (range 36-61). The median parity of the patients was 5 (range 0-8). Most patients were diagnosed at FIGO stage I. The mean survival for patients with stage I and II was 73.5 ± 35.09 and 57.6 ± 5.37 months, respectively, with mortality rate of 5.9% through a median follow-up time of 68.82 ± 30 months. Of 17 patients, seven cases (35.29%) were disease free at 6 years after hysterectomy. Radiotherapy was administered to four patients (23.53%). Only one patient recurred at 10th month after surgery. Surgeries not preserving ovarian function were helpful to decrease the risk of recurrence compared with those sparing ovarian function.  相似文献   
78.
Parkinson's disease (PD) is a progressive neurological disorder which is emanated by dopaminergic death cell and depletion. Curcumin as a nontoxic matter has antioxidant, anti-inflammatory, and antiproliferative activities, and it involves antioxidant property same to vitamins C and E. In this study, we investigated the neuroprotective properties of the natural polyphenolic antioxidant compound, curcumin, against homocysteine (Hcy) neurotoxicity. Curcumin (50 mg/kg) was injected intraperitoneally (i.p.) once daily for a period of 10 days beginning 5 days prior to Hcy (2 μmol/μl) intracerebroventricular (i.c.v.) injection in rats. The studies included immunohistological and locomotor activity tests. These results suggest that homocysteine intracerebroventricular administration (2 μmol/μl i.c.v.) may induce changes in rat brain, and subsequently, polyphenol treatment curcumin 50 mg/kg (i.p.) was capable in improving locomotor function in insulted animal by protecting the nervous system against homocysteine toxicity.  相似文献   
79.
ObjectiveThe present study aimed at evaluating the effectiveness of an educational intervention via mobile cells on foot care knowledge and foot care practices in patients with type 2 diabetes.Material and methodsThis is an interventional quasi-experimental study carried out in 4 community health centers in Andimeshk City in Iran in 2017. Of 160 patients 80 cases were randomly assigned as intervention group and 80 patients as the control one. A three-section questionnaire completed by a face-to-face interviewing used for data collection before and after the intervention and three months after the education. Fasting Blood Sugar (FBS) and Hemoglobin A1C (HbA1c) tests were done for both groups in a single laboratory before and three months after training.ResultsThe mean age of patients in intervention group was 48.11 ± 9.7 and control group was 47.3 ± 7.9 years. The awareness of the patients related to diabetes foot care, in the intervention group after the training significantly improved (P < 0.001). The mean scores of preventive behaviors of diabetic foot significantly increased in the intervention group (P < 0.001).ConclusionThe findings indicate that educational intervention based on short message service (SMS), resulting in improve foot care knowledge, foot care practices and metabolic control in patients with diabetes type 2.  相似文献   
80.

Background

Verbal autopsy (VA) has often been used for point estimates of cause-specific mortality, but seldom to characterize long-term changes in epidemic patterns. Monitoring emerging causes of death involves practitioners' developing perceptions of diseases and demands consistent methods and practices. Here we retrospectively analyze HIV-related mortality in South Africa, using physician and modeled interpretation.

Methods

Between 1992 and 2005, 94% of 6,153 deaths which occurred in the Agincourt subdistrict had VAs completed, and coded by two physicians and the InterVA model. The physician causes of death were consolidated into a single consensus underlying cause per case, with an additional physician arbitrating where different diagnoses persisted. HIV-related mortality rates and proportions of deaths coded as HIV-related by individual physicians, physician consensus, and the InterVA model were compared over time.

Results

Approximately 20% of deaths were HIV-related, ranging from early low levels to tenfold-higher later population rates (2.5 per 1,000 person-years). Rates were higher among children under 5 years and adults 20 to 64 years. Adult mortality shifted to older ages as the epidemic progressed, with a noticeable number of HIV-related deaths in the over-65 year age group latterly. Early InterVA results suggested slightly higher initial HIV-related mortality than physician consensus found. Overall, physician consensus and InterVA results characterized the epidemic very similarly. Individual physicians showed marked interobserver variation, with consensus findings generally reflecting slightly lower proportions of HIV-related deaths. Aggregated findings for first versus second physician did not differ appreciably.

Conclusions

VA effectively detected a very significant epidemic of HIV-related mortality. Using either physicians or InterVA gave closely comparable findings regarding the epidemic. The consistency between two physician coders per case (from a pool of 14) suggests that double coding may be unnecessary, although the consensus rate of HIV-related mortality was approximately 8% lower than by individual physicians. Consistency within and between individual physicians, individual perceptions of epidemic dynamics, and the inherent consistency of models are important considerations here. The ability of the InterVA model to track a more than tenfold increase in HIV-related mortality over time suggests that finely tuned "local" versions of models for VA interpretation are not necessary.  相似文献   
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