Repository of Research and Investigative Information Isfahan University of Medical Sciences
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Dengue virus: Etiology, epidemiology, pathobiology, and developments in diagnosis and control - A comprehensive review
No full textDengue flavivirus (DENV) is the virus that causes dengue, one of the most dangerous and common viral diseases in humans that are carried by mosquitoes and can lead to fatalities. Every year, there are over 400 million cases of dengue fever worldwide, and 22,000 fatalities. It has been documented in tropical and subtropical climates in over 100 nations. Unfortunately, there is no specific treatment approach, but prevention, adequate awareness, diagnosis in the early stages of viral infection and proper medical care can reduce the mortality rate. The first licensed vaccine for dengue virus (CYD Denvaxia) was quadrivalent, but it is not approved in all countries. The primary barriers to vaccine development include inadequate animal models, inadequate etiology mechanistic studies, and adverse drug events. This study provides current knowledge and a comprehensive view of the biology, production and reproduction, transmission, pathogenesis and diagnosis, epidemiology and control measures of dengue virus
MRI-based radiomics for prediction of biochemical recurrence in prostate cancer: a systematic review and meta-analysis
No full textBackground and purpose Biochemical recurrence (BCR) following prostate cancer (PCa) treatment is a significant indicator of metastasis and mortality. Early prediction of BCR can guide treatment decisions, and optimize patient management strategies. MRI is essential for the diagnosis and surveillance of PCa. This study aimed to assess the accuracy and quality of MRI radiomics-based machine learning (ML) models for predicting post-treatment BCR in PCa. Methods A systematic literature search was conducted across five electronic databases (PubMed, Scopus, Embase, Web of Science, and IEEE) up to December 23, 2024, to identify studies developing ML models based on MRI-derived radiomics features for the prediction of BCR in PCa. Studies were assessed for quality using the QUADAS-2 and METRICS tools. A meta-analysis of radiomics, clinical, and clinical-radiomics models in validation cohorts was performed to pool sensitivity, specificity, and area under the curve (AUC) using a bivariate random-effects model. Results A total of 24 studies were incorporated into the systematic review, with 14 included in the meta-analysis. The pooled AUC, sensitivity, and specificity for radiomics-based ML models were 0.75, 72, and 78, respectively. Clinical-radiomics models showed the highest performance with a pooled AUC of 0.88, sensitivity of 85, and specificity of 79. QUADAS-2 revealed significant methodological biases, particularly in the index test and flow and timing domains. The mean METRICS score across studies was 65.68, ranging from 43.8 to 82.2, showing overall good quality but highlighting methodological gaps in some domains. Conclusion MRI-based radiomics demonstrates potential for predicting BCR in PCa, especially when integrated with clinical variables. However, it is still far from widespread clinical use, necessitating further standardization and key methodological improvements for better generalizability and robustness. Future studies should adopt multi-center designs and conduct thorough external validation to enhance applicability across diverse patient populations
Health risk assessment and Sobol' sensitivity analysis of power plant air pollution (SO2 and NOX): the effect of power plant fuel change
No full textThis study aimed to evaluate the concentrations of sulfur dioxide (SO2) and nitrogen oxides (NOX) around the Qom (a province in Iran) combined cycle power plant in relation to seasonal variations and fuel type from December 2014 to May 2015. Passive sampling was used in three monitoring sites around the power plant to assess noncarcinogenic health risks associated with exposure to SO2 and NOX. Results showed the higher concentrations of NOX and SO2 in winter than in spring. The highest concentrations of NOX in winter (when power plants used gasoil) and spring (when power plants used gas fuel) were 52.70 +/- 21.70/52.70 +/- 13.20 and 22.10 +/- 7.00 mu g/m(3). Similarly, the highest concentrations of SO2 in winter and spring were 5.00 +/- 0.20 and 3.90 +/- 0.70 mu g/m(3). There was a moderately significant correlation between NOx and SO2 concentrations when the power plant consumed gasoil (Spearman rho coefficient, 0.68, p < .05). A significant difference was observed between gas concentration and fuel type (p < .05). The hazard quotient values for SO2 exposure were below 1 for all age groups, whereas those for NOx were above 1 for infants and children. The hazard index for NOX was above 1, indicating an unacceptable risk to human health. Sobol' sensitivity analysis identified the inhalation rate and NOX concentration as the most significant factors determining the noncarcinogenic risks across age groups. In conclusion, the use of gasoil by power plants increases the emission of pollutants, thereby raising the health risks for residents in these regions, particularly vulnerable demographics like children. Therefore, prioritizing air quality management such as using cleaner fuels and emission control technologies in power plants as well as continuous air quality monitoring are of utmost importance
The association between global and prime diet quality scores and the risk of bacterial vaginosis: a secondary analysis of case-control study
No full textIntroductionThe present aimed to examine the relationship between Global Diet Quality (GDQ) and Prime Diet Quality (PDQ) scores and the likelihood of bacterial vaginosis (BV) among women.MethodsThis case-control study was conducted among patients referred to a gynecological clinic in Tehran using the convenience sampling method. All the participants were examined by a gynecologist to rule out BV based on the presence of three or four of Amsel criteria. A valid semi-quantitative food frequency questionnaire (FFQ) containing 168 food items was used to estimate participants' dietary intake. To calculate the GDQ score, 25 food groups were considered, while 21 food groups were used for the PDQ score, based on the of daily consumption (in grams). All statistical analysis were performed using SPSS, and the association between GDQ and PDQ scores and the odds of BV was evaluated using binary logistic regression.ResultsAfter adjusting for age, energy intake, fat intake, BMI, physical activity, familial history of BV, pregnancy history, menstrual cycle, smoking history, and the number of sexual partners in the previous month, significant associations remained between highest tertile of GDQ total (odds ratio (OR) = 0.219, confidence interval (CI) 95: 0.101-0.475) and positive score (OR = 0.235, CI 95: 0.103-0.533), as well as PDQ total (OR = 0.277, CI 95: 0.131-0.583) and healthy score (OR = 0.397, CI 95: 0.185-0.854) with the odds of BV, compared to the first tertile.ConclusionA high diet quality, as indicated by high GDQ and PDQ scores, was associated with decreased risk of BV. These findings suggest that dietary intervention may be a viable strategy for the prevention and management of BV
Implants with or without Leukocyte- and Platelet-Rich Fibrin (L-PRF): A Systematic Review on Dental Implant Stability
No full textBackgroundTo examine the impact of applying leukocyte- and platelet-rich fibrin (L-PRF) on the stability of dental implants using implant stability quotient (ISQ) measurements.MethodsA systematic search of the main databases was conducted to source the literature. Studies that met the established inclusion and exclusion criteria were selected for this review. The focus was solely on randomized controlled trials (RCTs) and controlled clinical trials (CCTs).ResultsAfter conducting a comprehensive search, a total of 1984 studies were identified. Following evaluation based on our inclusion and exclusion criteria, a refined selection of 7 studies was chosen for detailed review in this analysis.ConclusionsOur findings indicate that the use of leukocyte- and platelet-rich fibrin (L-PRF) may enhance the stability of implants following surgical procedures. This suggests that L-PRF may accelerate the healing process, reduce the loading time, and improve outcomes for patients undergoing implant surgery, potentially reducing the risk of implant failures and complications
Uncovering cerebral blood flow patterns corresponding to Amyloid-beta accumulations in patients across the Alzheimer's disease continuum using the arterial spin labeling
No full textBackgroundAlzheimer's disease (AD) is a progressive neurodegenerative disorder ranging from mild cognitive impairment (MCI) to AD dementia. Abnormal cerebral perfusion alterations, influenced by amyloid-beta (A beta) accumulations, have been implicated in cognitive decline along this spectrum.ObjectiveThis study investigates the relationship between cerebrospinal fluid (CSF) A beta 1-42 levels and regional cerebral blood flow (CBF) changes across the AD continuum using the Arterial Spin Labeling (ASL) technique.MethodsWe analyzed data from 229 participants extracted from the ADNI cohort, comprising of 50 cognitively normal (CN), 13 subjective memory complaints (SMC), 83 early MCI (EMCI), 52 late MCI (LMCI), and 31 AD participants with complete ASL and CSF data. Correlations between A beta 1-42 levels and regional mean CBF values were assessed. Multiple linear regression models accounted for confounders, including age, gender, and education level.ResultsPreliminary unadjusted analyses revealed strong positive correlations between A beta 1-42 levels and CBF in multiple regions, predominantly in the AD group. After adjusting for confounders, significant correlations in AD participants emerged in the left pars triangularis and left caudal middle frontal cortex. In the LMCI group, significant associations were identified in the right lateral occipital cortex, right inferior parietal cortex, and left amygdala.ConclusionThese findings highlight the critical role of A beta-driven CBF alterations in regions associated with higher cognitive functions and suggest that these patterns may serve as potential biomarkers for diagnosing and monitoring disease progression
Autophagy and the peroxisome proliferator-activated receptor signaling pathway: A molecular ballet in lipid metabolism and homeostasis
No full textLipids, which are indispensable for cellular architecture and energy storage, predominantly consist of triglycerides (TGs), phospholipids, cholesterol, and their derivatives. These hydrophobic entities are housed within dynamic lipid droplets (LDs), which expand and contract in response to nutrient availability. Historically perceived as a cellular waste disposal mechanism, autophagy has now been recognized as a crucial regulator of metabolism. Within this framework, lipophagy, the selective degradation of LDs, plays a fundamental role in maintaining lipid homeostasis. Dysregulated lipid metabolism and autophagy are frequently associated with metabolic disorders such as obesity and atherosclerosis. In this context, peroxisome proliferator-activated receptors (PPARs), particularly PPAR-gamma, serve as intracellular lipid sensors and master regulators of gene expression. Their regulatory influence extends to both autophagy and lipid metabolism, indicating a complex interplay between these processes. This review explores the hypothesis that PPARs may directly modulate autophagy within the realm of lipid metabolism, thereby contributing to the pathogenesis of metabolic diseases. By elucidating the underlying molecular mechanisms, we aim to provide a comprehensive understanding of the intricate regulatory network that connects PPARs, autophagy, and lipid homeostasis. The crosstalk between PPARs and other signaling pathways underscores the complexity of their regulatory functions and the potential for therapeutic interventions targeting these pathways. The intricate relationships among PPARs, autophagy, and lipid metabolism represent a pivotal area of research with significant implications for understanding and treating metabolic disorders
Renal Denervation Effects on Blood Pressure in Resistant and Uncontrolled Hypertension: A Meta-Analysis of Sham-Controlled Randomized Clinical Trials
No full textBackground: Although some guidelines recommend Renal denervation (RDN) as an alternative to anti-HTN medications, there are concerns about its efficacy and safety. We aimed to evaluate the benefits and harms of RDN in a systematic review and meta-analysis of sham-controlled randomized clinical trials (RCT). Methods: Databases were searched until September 10th, 2024, to identify RCTs evaluating RDN for treating URH versus sham control. The primary outcomes were the change in office and ambulatory 24-h systolic (SBP) and diastolic blood pressure (DBP). Secondary outcomes were changes in daytime and nighttime SBP and DBP, home BP, number of anti-HTN drugs, and related complications. Mean differences (MD) and relative risks (RR) described the effects of RDN on BP and complications, respectively, using random effects meta-analyses. GRADE methodology was used to assess the certainty of evidence (COE). Results: We found 16 included sham-controlled RCTs RDN (n = 1594) vs. sham (n = 1225). RDN significantly reduced office SBP (MD -4.26 mmHg, 95% CI: -5.68 to -2.84), 24 h ambulatory SBP (MD -2.63 mmHg), office DBP (MD -2.15 mmHg), 24-h ambulatory DBP (MD -1.27 mmHg), and daytime SBP and DBP (MD -3.29 and 2.97 mmHg), compared to the sham. The rate of severe complications was low in both groups (0%-2%). The heterogeneity was high among most indices, and CoE was very low for most outcomes. Conclusion: RDN significantly reduced several SBP and DBP outcomes versus sham without significantly increasing complications. This makes RDN a potentially effective alternative to medications in URH
Secondary Prevention Medications in 17 Countries Grouped by Income Level (PURE) A Prospective Cohort Study
No full textBACKGROUND It is unclear whether global use of medications for secondary cardiovascular (CVD) prevention is improving over time. OBJECTIVES This study across 17 high-, middle- and low-income countries described variations in secondary CVD prevention medication use over a median follow-up of 12 years. METHODS In the multinational PURE (Prospective Urban Rural Epidemiology) cohort study, we conducted a repeated cross-sectional analysis to examine temporal variations in the use of secondary prevention medications in participants with CVD. In participants with coronary artery disease, we focused on antiplatelet agents, statins, renin-angiotensin system (RAS) inhibitors, and b-blockers. In participants with stroke, we focused on antiplatelet agents, statins, RAS inhibitors, and other blood pressure-lowering drugs. Medications were collected at baseline and on 4 subsequent followup visits. RESULTS The analysis included 7,409 participants with a diagnosis of CVD at the baseline visit, 8,792 at the second visit, 9,236 at the third visit, 11,082 at the fourth visit, and 11,677 at the last visit. The median age at baseline was 58.0 years, and 52.9 of the participants were female. The median follow-up was 12 years, with the median year of the baseline visit in 2007 and the fifth visit in 2019. Over this period, use of 1 or more classes of medications for secondary CVD prevention was 41.3 (95 CI: 40.2-42.4) at baseline, peaked at 43.1 (95 CI: 42.0-44.1), and then decreased to 31.3 (95 CI: 30.4-32.1) by the last study visit. In high-income countries, this use decreased from 88.8 (95 CI: 86.6-91.0) to 77.3 (95 CI: 74.9-79.6). In upper-middle-income countries, this use increased from 55.0 (95 CI: 52.8-57.3) to 61.1 (95 CI: 59.1-63.1). In lower-middle-income countries, use of at least 1 class of medications was 29.5 (95 CI: 28.1-30.9) at baseline, peaked at 31.7 (95 CI: 30.4-33.1), and then decreased to 13.4 (95 CI: 12.5-14.2) by the last visit. In low-income countries, use of at least 1 class of medications was 20.8 (95 CI: 18.1-23.5) at baseline, peaked at 47.3 (95 CI: 44.8-49.9), and then decreased to 27.5 (95 CI: 25.2-29.9) by the last study visit. CONCLUSIONS Globally and in most country income-level groups, the use of medications for secondary CVD prevention has been low, with little improvement over time. (JACC. 2025;85:436-447) (c) 2025 by the American College of Cardiology Foundation
Engineering Folic Acid-Modified Nanoparticles to Enhance Letrozole's Anticancer Action
No full textThe development of biodegradable nanoparticles (NPs) for delivering anticancer drugs, such as letrozole (LTZ), offers a targeted approach for cancer therapy. In this study, we synthesized poly(epsilon-caprolactone)-co-poly(ethylene glycol) (PCL-co-PEG) and fabricated LTZ-loaded PCL-co-PEG NPs (LTZ-NPs) via emulsion-solvent evaporation. Folic acid (FA), a folate receptor-targeting molecule, was conjugated to the LTZ-loaded NPs (LTZ-FNPs) to enhance treatment efficacy against hormone receptor-positive breast cancer cells. Both NPs and FNPs exhibited a spherical morphology (60-90 nm), with FNPs showing higher drug entrapment efficiency and controlled release. LTZ release was minimal at physiological pH but increased in acidic, cancer-like environments, following the Korsmeyer-Peppas model, indicating a combination of Fickian and non-Fickian diffusion. In cytotoxicity assays, LTZ-FNPs exhibited higher toxicity against MCF-7 cells than LTZ-NPs. Controlled LTZ release altered gene expression, reducing B-cell leukemia/lymphoma 2 protein (Bcl2) and increasing caspase 8 (Casp8), promoting apoptosis. A shift to the SubG1 phase further confirmed enhanced LTZ-FNP-mediated cell death. Furthermore, p53 expression increased, while matrix metalloproteinase 9 (MMP-9) decreased, inhibiting cell invasion. This study introduces a biodegradable system with FA-functionalized, pH-sensitive NPs for the targeted and controlled delivery of LTZ. This approach holds great potential for selective, efficient treatment while minimizing systemic toxicity in breast cancer therapy