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Background Patients with membranous nephropathy (MN) and poor kidney function or active disease despite previous immunosuppression are underrepresented in clinical trials. It is unknown how effective rituximab is in this population. Methods This prospective, multi-centre, single-arm, real-world study of patients with active MN [urine protein-creatinine ratio (uPCR) >350 mg/mmol and serum albumin <30 g/L, or a fall in estimated glomerular filtration rate (eGFR) of at least 20% or more over at least 3 months] evaluated rituximab in those with contraindications to calcineurin inhibitors and cytotoxic therapy. The primary outcome was change in rate of eGFR decline before and after rituximab. Complete or partial remission were defined as uPCR <30 mg/mmol or uPCR <350 mg/mmol with a ≥50% fall from baseline, respectively. Results A total of 180 patients [median age 59 years, interquartile range (IQR) 48–68] received rituximab and were followed up for a median duration of 17 months. Seventy-seven percent had prior immunosuppression. Median eGFR and uPCR at baseline were 49.2 mL/min/1.73 m2 (IQR 34.4–80.6) and 766 mg/mmol (IQR 487–1057), respectively. The annual rate of decline of eGFR fell from 13.9 to 1.7 mL/min/1.73 m2/year following rituximab (Z score = 2.48, P < .0066). At 18 months 12% and 42% of patients were in complete or partial remission, respectively. Rituximab was well tolerated; patient survival was 95.6% at 2 years and in patients in whom eGFR was available, kidney survival was 93% at 2 years. Conclusion Rituximab significantly reduced the rate of eGFR decline in active MN including those who had received prior immunosuppression or with poor baseline kidney function. [ABSTRACT FROM AUTHOR]

Objectives: Delayed post-gadolinium magnetic resonance imaging (MRI) detects changes of endolymphatic hydrops (EH) within the inner ear in Meniere's disease (MD). A systematic review with meta-analysis was conducted to summarise the diagnostic performance of MRI descriptors across the range of MD clinical classifications. Materials and methods: Case-controlled studies documenting the diagnostic performance of MRI descriptors in distinguishing MD ears from asymptomatic ears or ears with other audio-vestibular conditions were identified (MEDLINE, EMBASE, Web of Science, Scopus databases: updated 17/2/2022). Methodological quality was evaluated with Quality Assessment of Diagnostic Accuracy Studies version 2. Results were pooled using a bivariate random-effects model for evaluation of sensitivity, specificity and diagnostic odds ratio (DOR). Meta-regression evaluated sources of heterogeneity, and subgroup analysis for individual clinical classifications was performed. Results: The meta-analysis included 66 unique studies and 3073 ears with MD (mean age 40.2–67.2 years), evaluating 11 MRI descriptors. The combination of increased perilymphatic enhancement (PLE) and EH (3 studies, 122 MD ears) achieved the highest sensitivity (87% (95% CI: 79.92%)) whilst maintaining high specificity (91% (95% CI: 85.95%)). The diagnostic performance of "high grade cochlear EH" and "any EH" descriptors did not significantly differ between monosymptomatic cochlear MD and the latest reference standard for definite MD (p = 0.3; p = 0.09). Potential sources of bias were case-controlled design, unblinded observers and variable reference standard, whilst differing MRI techniques introduced heterogeneity. Conclusions: The combination of increased PLE and EH optimised sensitivity and specificity for MD, whilst some MRI descriptors also performed well in diagnosing monosymptomatic cochlear MD. Key Points: • A meta-analysis of delayed post-gadolinium magnetic resonance imaging (MRI) for the diagnosis of Meniere's disease is reported for the first time and comprised 66 studies (3073 ears). • Increased enhancement of the perilymphatic space of the inner ear is shown to be a key MRI feature for the diagnosis of Meniere's disease. • MRI diagnosis of Meniere's disease can be usefully applied across a range of clinical classifications including patients with cochlear symptoms alone. [ABSTRACT FROM AUTHOR]

In this article, we introduce a new model derived from Pólya–Eggenberger urn model. This model is defined by considering a delay in collecting information. The mathematical formulation of this model is done through four parameters; the number of balls in the first structure (N0), the number of white balls in the first structure (W0), the number of rewarded balls of the color of the ball withdrawn (a), and the length of the delay (i). As the first attempt to deal with point estimation in this model, we consider at any time one of the parameters separately as unknown conditioned to knowing the other three parameters, and find its estimation. Accordingly, we introduce a sufficient estimator for this model, and found on it, obtain the maximum likelihood estimators for each of the four parameters. In addition, moment estimators for N0 and W0 are calculated. Also, for the other parameters, we obtain estimators based on the correlation coefficient of consecutive withdrawals. To evaluate the performance of the obtained estimators and compare their accuracy, we apply five simulations of the delayed Pólya urn model. The simulations have been done with the software Matlab R2015b. According to the simulation study, the estimators obtained from the method of moments are preferable to maximum likelihood estimators. [ABSTRACT FROM AUTHOR]

Recent advances in medical instruments, information technology, and unprecedented data sharing allowed scientists to investigate, trace, and monitor the COVID-19 pandemic faster than any previous outbreak. This extraordinary speed makes COVID-19 a medical revolution that causes some unprecedented analyses, discussions, and models. Modeling the dependence between the number of tests and the positivity rate is one of these new issues. Using four classes of copulas (Clayton, Frank, Gumbel, and FGM), this study is the first attempt tom model the dependency. The estimation of the parameters of the copulas is obtained using the maximum likelihood method. To evaluate the goodness of fit of the copulas, we calculate AIC. The computations are conducted on Matlab R2015b, R 4.0.3, Maple 2018a, and EasyFit 5.6. Findings indicate that at the beginning of a typical epidemic, the number of tests is relatively low and the proportion of positivity is high. As time passes, the number of tests increases, and the positivity rate decreases. The epidemic peaks are occasions that violate the stated general rule –due to the early growth of the number of tests. Also, during both peak and non-peak times, the rising number of tests is accompanied by decreasing the positivity rate. We find that the proportion of positivity is more proportional than the number of tests to the number of infected cases. Therefore, the changes in the positivity rate can be considered a representative of the level of the spreading. Approaching zero positivity rate is a good criterion to scale the success of a healthcare system in fighting against an epidemic. Accordingly, the number and accuracy of tests can play a vital role in the quality level of epidemic data. [ABSTRACT FROM AUTHOR]

Pólya urn models are of the well-known probabilistic concepts and stochastic processes. The proportion of the colors is the question of the most interest in these models. Always, the structure (The number of all the balls in the urn and the proportion of the colors) of the urn at the beginning is given. Also, in the studies where the outcome of certain withdrawals is known, these withdrawals are connected to the first structure, and there is no gap between the known structure and the additional information about the color of the withdrawn balls. The existing gap between the first structure and any relevant information motivates this paper. In the present article, we consider the Pólya-Eggenberger urn model. We prove that an urn with an initial known structure after some unknown withdrawals – conditioned to meet an assumption – behaves like an urn with a known structure. By the results of the present paper, we overcome the complexity and ambiguity caused by the unknown withdrawals, and in spite of the lack of information concerning some withdrawals, we deal with the urn as a process that behaves like a completely determined structure. To illustrate the truth of the obtained results, we simulate several urns and survey the variation in the probabilities of the colors. [ABSTRACT FROM AUTHOR]

Objective: The UK is one of the epicenters of coronavirus disease (COVID-19) in the world. As of April 14, there have been 93 873 confirmed patients of COVID-19 in the UK and 12 107 deaths with confirmed infection. On April 14, it was reported that COVID-19 was the cause of more than half of the deaths in London. Methods: The present paper addresses the modeling and forecasting of the outbreak of COVID-19 in the UK. This modeling must be accomplished through a 2-part time series model to study the number of confirmed cases and deaths. The period we aimed at a forecast was 46 days from April 15 to May 30, 2020. All the computations and simulations were conducted on Matlab R2015b, and the average curves and confidence intervals were calculated based on 100 simulations of the fitted models. Results: According to the obtained model, we expect that the cumulative number of confirmed cases will reach 282 000 with an 80% confidence interval (242 000 to 316 500) on May 30, from 93 873 on April 14. In addition, it is expected that, over this period, the number of daily new confirmed cases will fall to the interval 1330 to 6450 with the probability of 0.80 by the point estimation around 3100. Regarding death, our model establishes that the real case fatality rate of the pandemic in the UK approaches 11% (80% confidence interval: 8%–15%). Accordingly, we forecast that the total death in the UK will rise to 35 000 (28 000–50 000 with the probability of 80%). Conclusions: The drawback of this study is the shortage of observations. Also, to conduct a more exact study, it is possible to take the number of the tests into account as an explanatory variable besides time. [ABSTRACT FROM AUTHOR]

In this paper, we define and study a stochastic SIR model on the class of regular rooted trees, in order to describe the spread of an epidemic on a closed population. A generalized geometric random variable is defined, which is essential for our study in this stochastic process. The main objective of this paper is to obtain the distribution of random variable X , the number of infected individuals at the stopping time that a diagnosis occurs. The analyses, simulations, and figures created with the software MATLAB certify the validity of the obtained results. [ABSTRACT FROM AUTHOR]

Background: Quality of life (QOL) is one of the major factors to assessing the health and wellbeing of People living with HIV (PLWH). Likewise, improved QOL is among the prominent goals of patient treatment. This study was conducted to investigate the QOL of PLWH in Kermanshah, Iran.Methods: This cross-sectional study was conducted on 364 PLWH of Kermanshah between 2016 and 2017. Outpatients were selected as the sample through the convenience sampling method from HIV Positive Clients of Kermanshah Behavioral Diseases Counseling Center. The reasons for the selection of outpatients include: (a) some patients were substance users, homeless or did not have a fixed address to follow-up; (b) addresses and personal details that were registered on the first admission were incorrect or incomplete; (c) due to financial issues, some were forced to relocate frequently and were difficult to track; (d) some patients were convicts or prisoners, making it hard to find them after their release; (e) some of them were from other provinces, where managing access was not easy/possible. Data was collected using WHOQOL-HIV BREF questionnaire (Persian Version). Data also analyzed with STATA 14, and SPSS 23 using T-test and multiple regression.Results: This study showed that mean (SD) age of PLWH was 40.21 (10.45) years. Females had better QOL than males except for spirituality, religion and personal beliefs. The gender differences disappeared in multivariate results. A significant association was observed between education and the independence, environment, and spirituality domains of QOL. In addition, being married was correlated with overall QOL, psychological and social relationships domains of QOL of PLWH. Drug use was a behavioral factor with negative influence on the QOL.Conclusion: This study found that marital status and drug use were the main predictors of various domains of QOL. Drug use was a behavioral factor with a negative influence on the QOL. Hence, it is recommended that health professionals, planners, and policymakers take effective measures to improve the status quo. [ABSTRACT FROM AUTHOR]

Background: COVID-19 is the most informative pandemic in history. These unprecedented recorded data give rise to some novel concepts, discussions and models. Macroscopic modeling of the period of hospitalization is one of these new issues.Methods: Modeling of the lag between diagnosis and death is done by using two classes of macroscopic analytical methods: the correlation-based methods based on Pearson, Spearman and Kendall correlation coefficients, and the logarithmic methods of two types. Also, we apply eight weighted average methods to smooth the time series before calculating the distance. We consider five lags with the least distance. All the computations are conducted on Matlab R2015b.Results: The length of hospitalization for the fatal cases in the USA, Italy and Germany are 2-10, 1-6 and 5-19 days, respectively. Overall, this length in the USA is 2 days more than that in Italy and 5 days less than that in Germany.Conclusion: We take the distance between the diagnosis and death as the length of hospitalization. There is a negative association between the length of hospitalization and the case fatality rate. Therefore, the estimation of the length of hospitalization by using these macroscopic mathematical methods can be introduced as an indicator to scale the success of the countries fighting the ongoing pandemic. [ABSTRACT FROM AUTHOR]