Journal of Studies in Medical Sciences
Volume:35 Issue: 12, 2025

 Chemoresistance, particularly to topotecan (TPT), remains a major obstacle in colorectal cancer treatment. As a topoisomerase I inhibitor, TPT's efficacy is limited by P-glycoprotein (P-gp)-mediated drug resistance. This study examined melatonin's potential to overcome TPT resistance in SW480/TPT cells and its underlying mechanisms.

SW480 and drug-resistant SW480/TPT cells were maintained in RPMI-1640/10% FBS. Cells were treated with TPT (0.1-5 μM) alone or combined with melatonin (1-20 μM) in serum-free medium for 48 hours. Apoptosis was quantified using the Cell Death Detection ELISA™ kit. MDR1 expression and P-gp levels were assessed after melatonin treatment (10 μM, 48h). All experiments included ≥3 biological replicates, with data analyzed by one-way ANOVA.

Melatonin synergistically enhanced TPT efficacy, reducing the IC50 from 2.8±0.3 μM to 0.8±0.1 μM (71.4% reduction, p<0.001). Combination therapy increased apoptosis from 15±2% (TPT alone) to 45±4% (3-fold increase, p<0.001). Mechanistically, melatonin downregulated MDR1 expression by 65±5% and decreased P-gp levels by 58±4% versus untreated controls (p<0.001).

Melatonin significantly reverses TPT resistance in colorectal cancer cells by suppressing P-gp/MDR1. These findings position melatonin as a promising adjuvant for combination chemotherapy, warranting further investigation in preclinical models and clinical trials.

Telocytes are a novel type of mesenchymal cell characterized by a small cell body and distinctive, long extensions called telopods. They are found in many tissues throughout the body. Telopods enable telocytes to communicate with other cells over long distances. Functionally, telocytes play a vital role in maintaining tissue homeostasis, modulating the immune response, promoting tissue repair, and regulating the activity of other cell types. Although definitive markers for identifying telocytes are not yet fully established, they commonly express proteins such as CD34, c-kit, and vimentin. The study of these cells is important for several reasons. Understanding the role of telocytes in various diseases can help develop new treatments. Identifying specific receptors and signaling molecules of telocytes can lead to the development of new drugs to treat diseases. Due to their role in tissue repair, telocytes have significant potential for use in regenerative medicine. However, challenges remain in identifying and understanding the precise function of telocytes in different tissues. The functional diversity of telocytes in different tissues makes their study complex, and the precise molecular mechanisms of telocyte function are not yet fully understood. As a new and exciting research area, telocytes have significant potential to increase our understanding of tissue physiology and diseases.

  Infection is a cause of fever and seizures, and urinary tract infections are common in childhood. Delayed diagnosis may lead to severe complications. Given the conflicting results in studies examining the relationship between febrile seizures and urinary tract infection in children, this study aimed to investigate the prevalence of urinary tract infections in children with fever and seizures at the Shahid Motahari Educational Center, Urmia.

This retrospective cross-sectional study included 790 patients aged 6–60 months with fever and seizures who were referred to Shahid Motahari Hospital, Urmia, between April 2021 and March 2022. Demographic characteristics and clinical parameters were extracted and analyzed from the patient records. Urinary tract infections were characterized by the presence of more than 100,000 bacterial colonies per milliliter of urine.

The prevalence of urinary tract infections in children with fever and seizures was 9.87%. The mean age of patients with urinary tract infection was 35.85±12.96 months, with a urinary tract infection frequency of 57.69% in boys and 42.30% in girls. Fever of 38.5–39°C was most frequent, and the mean duration was 31.59±10.63 hours, with most patients experiencing high fever for 24 to 36 hours. The interval between fever onset and seizures was 12.97±3.09 hours, with most seizures occurring within 9 to 12 hours of fever onset. Escherichia coli was the most prevalent urinary microorganism. Among the patients, 6 (7.69%) had a family history of fever and seizures, 9 (11.53%) had a history of fever and seizures, and 14 (17.94%) had a history of urinary tract infection.

This study indicated a significant prevalence of urinary tract infections in children with febrile seizures and provided insights into the demographic and clinical characteristics of this population. These findings emphasize the importance of routine screening for urinary tract infections in children with febrile seizures and the need for prompt treatment to prevent recurrent episodes and associated complications.

 Medicinal plants serve as a valuable resource for novel approaches to alleviating dementia symptoms. In Persian medicine manuscripts, Melilotus officinalis (sweet clover) was proposed as a treatment for dementia-related symptoms. This study aimed to evaluate the cholinesterase inhibitory activity of sweet clover extracts and essential oil using Ellman’s method.

The essential oil from the aerial parts of sweet clover was obtained via hydrodistillation. Phytochemical composition of the volatile oil was analyzed by GC-MS. Additionally, the plant material was extracted using two solvent systems: (1) petroleum ether, ethyl acetate, and methanol; and (2) n-hexane, dichloromethane, and ethanol. The extracts were dehydrated via oven-drying and freeze-drying. Acetylcholinesterase inhibitory activity of the volatile oil and extracts was assessed using Ellman’s test. A preliminary phytochemical analysis of the ethanolic extract was performed by TLC.

GC-MS analysis of the volatile oil identified 45.67% of its phytoconstituents, comprising 18 compounds, including hexyl butyrate, phytol, octyl butyrate, and hexahydrofarnesyl acetone. Ellman’s test revealed that the volatile oil exhibited no inhibitory activity, whereas the freeze-dried ethanolic extract (200 µg/mL) showed 70.9% inhibition. The freeze-dried extract demonstrated significantly higher inhibitory activity than the oven-dried extract. TLC analysis of the ethanolic extract confirmed the presence of phenolic compounds and coumarins, which are likely responsible for its bioactivity.

The freeze-dried ethanolic extract exhibited the strongest acetylcholinesterase inhibitory activity, suggesting that freeze-drying is the preferred dehydration method for sweet clover extracts. Phenolic compounds and coumarins are probable contributors to this inhibitory effect.

 Sea cucumbers belong to the phylum Echinodermata and have applications in fisheries, food, pharmaceuticals, and medical industries. Additionally, the use of metal nanoparticles in drug delivery systems (nanodrugs) has contributed to innovations in dosage forms by improving therapeutic effects and physicochemical properties over the past several years. The aim of this study is to investigate and compare the cytotoxic activity of the alcoholic extract of the sea cucumber species Holothuria leocuspilota, based on its bioactive compounds, and to evaluate the effectiveness of plasmonic hybrid nanocarriers at different doses in treating colon cancer.

This study was conducted in vitro. Samples were collected from the intertidal zone of Lark Island in 2018, transferred to plastic containers containing seawater, and analyzed for their anticancer effects. The extract, obtained using methanol as a solvent, was tested alongside gold nanoparticles against the colon cancer cell line (HCT116).

Toxicity assessments conducted at 24, 48, and 72 hours revealed that cytotoxic effects increased proportionally with both extract and nanoparticle concentration, as well as with the duration of exposure. The best result was observed after 72 hours at a concentration of 500 micrograms of extract and 9 nanograms of nanoparticles. The IC50 value recorded during this period was 125 micrograms/ml.

Due to the significant cytotoxicity of the methanol extract against the cancer cell line, these compounds hold potential as viable candidates for anticancer drug development following further purification. Additionally, the plasmonic hybrid nanocarrier, which has demonstrated remarkable anticancer properties, could be extensively utilized in medical and pharmaceutical applications.

 Patellofemoral pain syndrome (PFPS) is a common condition in women, characterized by diffuse anterior or retropatellar knee pain. This systematic review aimed to evaluate the effectiveness of lower limb muscle strengthening in reducing pain among women with PFPS, with secondary outcomes assessing improvements in functional ability and balance.

A systematic review was conducted following the PRISMA guidelines. Studies published in Persian and English between January 2000 and January 2025 were retrieved from databases including SID, Web of Science, PubMed, Scopus, and Google Scholar. Eleven articles meeting the inclusion criteria (e.g., focus on lower limb strengthening interventions, female participants, and quantitative outcome reporting) were selected for final analysis.

The reviewed studies demonstrated that lower limb muscle strengthening significantly reduces pain and improves functional outcomes in women with PFPS. Hydrotherapy, particularly in deep water, was identified as an effective adjunct therapy, contributing to pain alleviation and balance enhancement. Evidence suggests that hydrotherapy may yield superior short-term results compared to land-based exercises. Furthermore, combining strengthening exercises with motor pattern re-education, stretching, and neuromuscular training provided additional benefits in pain reduction, functional improvement, and gait modification.

Lower limb muscle strengthening is a core therapeutic strategy for pain management and functional recovery in women with PFPS. Adjunctive interventions such as hydrotherapy and multimodal approaches may enhance treatment efficacy. Future research should prioritize long-term follow-ups and direct comparisons between therapeutic modalities to optimize clinical guidelines.

 Breast cancer remains the most prevalent malignancy, the leading cause of cancer-related mortality, and a significant public health challenge among women worldwide. This study aimed to investigate the epidemiological characteristics and contributing factors of breast cancer in Ardabil city during 2011-2022.

This cross-sectional analytical study examined all breast cancer cases identified in Ardabil County between 2011-2022. Primary data were extracted from medical records of patients initially diagnosed at Imam Khomeini Educational-Therapeutic Center. Supplementary information was collected using a researcher-designed checklist encompassing >40 demographic, clinical, lifestyle, and environmental variables from health center records. Data analysis was performed using SPSS-18, employing descriptive statistics (frequency, percentage, mean, SD) and analytical tests (Pearson correlation, logistic regression).

The annual incidence averaged 55 cases during the study period. Age-adjusted incidence rates were 14.3 and 15.3 per 100,000 women in 2011 and 2022, respectively. Patients' mean age was 53.6 years, with >99% being female and >96% married. Parity ranged from 0-11 children (mean: 4.5). Multivariate analysis identified two significant predictive factors: age >50 years (p<0.05) and exclusive breastfeeding duration <1 year (p<0.05), while other variables showed no significant association.

The incidence of breast cancer in Ardabil appears lower than national rates. Among risk factors, only advanced age and short breastfeeding duration demonstrated significant predictive value. We recommend: 1) Enhancing cancer registry systems with standardized risk factor documentation, 2) Establishing efficient referral networks between treatment centers and public health departments, and 3) Implementing continuous professional education programs for healthcare providers to improve case detection and data completeness.

 Given the clinical importance and frequent use of oxytocin in serum and pharmaceutical products, along with the significant impact of improper dosage on both the therapeutic efficacy and adverse effects, this study aimed to develop and validate a dispersive liquid-liquid microextraction (DLLME) method for the rapid and precise measurement of oxytocin concentrations in these matrices.

In this study, a DLLME method was optimized using carbon tetrachloride as the extraction solvent and acetonitrile as the dispersing solvent. Various parameters, including temperature and stirring speed, were systematically investigated and optimized. Analyses were conducted using gas chromatography with flame ionization detection (GC-FID). The materials utilized included oxytocin, ethanol, methanol, acetone, dichloromethane, carbon tetrachloride, acetonitrile, and calcitonin (as the internal standard).

Analysis of oxytocin concentrations in serum and commercial vials (5 and 10 IU/mL doses) from two domestic manufacturers (Company A and B) revealed that Company A’s products more closely matched their labeled concentrations compared to those of Company B. Method validation using a German reference standard (Rotexmedica) demonstrated comparable results for domestic samples, with no statistically significant differences observed. The analytical method showed excellent performance characteristics, with a linear detection range of 0.02–60 IU/mL, a calibration equation of A = 190731C − 21483, and a correlation coefficient (R²) of 0.999.

The developed DLLME method proved to be a simple, cost-effective, and reliable technique for quality control of oxytocin pharmaceutical preparations and the measurement of serum oxytocin levels. The findings revealed significant variations in oxytocin concentrations between different commercial products available in the Iranian market and demonstrated the method’s capability for accurate quantification in biological samples.