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Understanding the refractive profile, amblyopia prevalence, binocular status, and head position in patients with Brown syndrome help clinicians become more familiar with this syndrome. Brown syndrome is identified as an active and passive restricted elevation of the eye in adduction. There is little information on clinical features, including refractive status, amblyopia, abnormal head posture (AHP), and types of deviation in these patients. This study retrospectively evaluated records of 100 Brown syndrome patients from 2015 to 2022 at Farabi Eye Hospital, Iran. The mean age was 6.99 ± 6.33 years, including 48 (48%) males. A congenital source was found in 74 (74%) and 96 (96%) patients had unilateral involvement. The mean CDVA for the affected and non-affected eyes were 0.05 ± 0.11 and 0.03 ± 0.06 logMAR, respectively (P = 0.31). In unilateral cases, hyperopia, myopia, and emmetropia were observed in 55 (57.29%), 2 (2.08%), and 39 (40.63%) affected eyes, respectively. The most common type of deviation was pure hypotropia, which was found in 53 (53%) cases, followed by 'combined exotropia and hypotropia' observed in 26 (26%) patients. The mean angle of hypotropia and horizontal deviation in the primary position at distance was 12.10 ± 8.50 and 8 ± 13.20 prism dioptre, respectively. A V-pattern was found in 76 (76%) patients. Amblyopia was observed in 13 (21.67%) of 60 cooperative patients, and AHP was noticed in 66 (66%) patients, in which "combined chin up and contralateral face turn" was the most common type. About 75% of cases were congenital, 50% had pure hypotropia, 75% showed V-pattern, 20% had amblyopia, and AHP was observed in 67% of patients. The remarkable prevalence of amblyopia alongside the high occurrence of AHP should alert clinicians to carefully assess patients with Brown syndrome for sensory fusion and amblyopia. [ABSTRACT FROM AUTHOR]

The development of a conventional cumulative entropy was reported in this research within a fuzzy domain. For this purpose, the cumulative entropy and its estimators were developed based on fuzzy random variables to explore the predictability of the failure time of a system. Some common properties of the proposed fuzzy cumulative entropy and fuzzy empirical cumulative entropy were also discussed. The developed fuzzy entropies were illustrated via several numerical evaluations. [ABSTRACT FROM AUTHOR]

There are several studies on fuzzy univariate hypothesis tests corresponding to a normal distribution. A fuzzy statistical test was proposed in this study for mean and variance–covariance matrix of a multivariate normal with fuzzy random variables. For this purpose, a notion of fuzzy multivariate normal random variable with fuzzy mean and non-fuzzy variance–covariance matrix was first developed. Then, the concepts of the fuzzy type-I error, fuzzy type-II error, fuzzy power, non-fuzzy significance level and fuzzy p-value were extended. A degree-based criterion was also suggested to compare the fuzzy p-values as well as a specific significance level to decide whether accepting or rejecting the underlying hypotheses. The effectiveness of the proposed fuzzy hypothesis test was also examined through some numerical examples. [ABSTRACT FROM AUTHOR]

Background and objective: Huntington's disease (HD) is an autosomal dominant disorder that mainly affects adults. Although mutations in the IT15 gene have been known as the main cause of the disease, patients with HD like (HDL) syndrome have mutations in genes other than the IT15 gene. In this study, we investigate the frequency of mutations in SCA17/TBP, JPH3 and PRNP genes in patients with HDL syndrome. Methods: The frequency of mutations in SCA17/TBP, JPH3 and PRNP genes was studied in 56 patients with HDL phenotype but without trinucleotide expansion in the IT15 gene. DNA was extracted from peripheral whole blood by the salting out method. PCR was performed using specific primers for each gene. PCR products were separated on polyacrylamide gel. Sequencing was performed on some samples to confirm the PCR results. Results: We found neither trinucleotide expansion in the JPH3 and SCA17, nor octapeptide insertion in the PRNP gene. Conclusion: Based on the results, Iranian patients with HDL syndrome do not have mutation in the TBP, JPH3 and PRNP genes. However, this result may be due to population differences, rarity of the mutations in the studied genes and the small number of study subjects. Therefore, studies with a larger study population that investigate other mutations, such as point mutations in the mentioned genes may help clarify the exact cause of HDL phenotype in Iranian patients. [ABSTRACT FROM AUTHOR]

Several interpretations have been proposed so far for fuzzy random variables to describe imprecision and randomness. In this paper, a novel notion of fuzzy random variable was proposed to model fuzziness and randomness in a statistical procedure. For this purpose, a frequently used family of probability distributions called location and scale were first employed as the origin of randomness. Then, α-values of fuzzy numbers were combined with randomness to describe the fuzziness in the nature of the processes to produce a new concept of fuzzy random variable called location and scale fuzzy random variables. Then, some essential statistical features of the proposed fuzzy random variables including fuzzy cumulative distribution function, fuzzy expectation, exact variance and imprecise probability of an interval were discussed. The classical method of moment estimator was also developed to estimate the location and scale parameters. The developed technique was illustrated via several numerical evaluations. As an real-life application of the proposed fuzzy random variable, the reliability functions of k-out-of-n system and some reliability evaluation criteria were introduced and interpreted. Some numerical examples were also presented to illustrate the calculation of the proposed fuzzy system reliability criteria. [ABSTRACT FROM AUTHOR]

Background: Quality assessment and service delivery processes for cancer patients are the major components of palliative care. This study intends to explore stakeholder's perceptions of palliative care process challenges for cancer patients in Iran. Method: In this qualitative study, we conducted 22 semi-structured interviews from February 2016 to August 2017 in hospitals located in Tehran, Iran. Participants were selected through purposive sampling and included cancer patients, their family caregivers, healthcare providers, and policy-makers. The interviews were analyzed by qualitative directed content analysis based on the Donabedian model. In order to assess the accuracy and validity of the study, we used Lincoln and Guba's four criteria. Results: After analysis of the interviews, we categorized the codes into a main category, "process", and three identified subcategories - "weakness of stakeholders' engagement policies", "standardized care", and "applying educational and research approaches". Conclusion: Palliative care in Iran is a recent discipline. The results have shown that the process of providing services requires the attention of the health system to the standard models for providing palliative care services. In addition, it is necessary to train human resources in generalist and specialist palliative care groups, design palliative medicine curricula, inform general public about cancer, and empower patients and caregivers. [ABSTRACT FROM AUTHOR]

Ischemic stroke is an important cause of death and disability in the world. Brain ischemia causes damage to brain cell, and among brain neurons, pyramidal neurons of the hippocampal CA1 region are more susceptive to ischemic injury. Recent findings suggest that neurotrophic factors protect against ischemic cell death. A dietary component of Rosa damascene extract possibly is associated with expression of neurotrophic factors mRNA following ischemia, so it can have therapeutic effect on cerebral ischemia. The present study attempts to evaluate the neuroprotective effect of Rosa damascene extract on adult rat hippocampal neurons following ischemic brain injury. Forty-eight adult male Wistar rats (weighing 250±20 gr and ages 10-12 weeks) used in this study, animals randomly were divided into 6 groups including Control, ischemia/reperfusion (IR), vehicle and three treated groups (IR+0.5, 1, 2 mg/ml extract). Global ischemia was induced by bilateral common carotid arteries occlusion for 20 minutes. The treatment was done by different doses of Rosa damascena extract for 30 days. After 30 days cell death and gene expression in neurons of the CA1 region of the hippocampus were evaluated by Nissl staining and real time PCR assay. We found a significant decrease in NGF, BDNF and NT3 mRNA expression in neurons of CA1 region of the hippocampus in ischemia group compared to control group (P<0.0001). Our results also revealed that the number of dark neurons significantly increases in ischemia group compared to control group (P<0.0001). Following treatment with Rosa damascene extract reduced the number of dark neurons that was associated with NGF, NT3, and BDNF mRNA expression. All doses level had positive effects, but the most effective dose of Rosa damascena extract was 1 mg/ml. Our results suggest that neuroprotective activity of Rosa damascena can enhance hippocampal CA1 neuronal survival after global ischemia. [ABSTRACT FROM AUTHOR]