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Background and objectives: Medicinal plants have long been considered as one of the most important pillars of traditional medicine. Existing challenges in the treatment of diseases, particularly infectious diseases, are major drivers for herbal medicine studies. Tribulus terrestris has been widely used in traditional medicine to treat various diseases. This study aimed to investigate in vitro antibacterial effect of the aqueous extract of T. terrestris on several oral bacteria.

Methods: In this experimental study, after preparing the aqueous extract of T. terrestris, minimum inhibitory and bactericidal concentrations (MIC and MBC) of the extract were determined against standard strains of Streptococcus mutans, Staphylococcus aureus, Klebsiella pneumoniae and Streptococcus pyogenes using the broth microdilution method. The experiments were repeated three times and the results were analyzed with SPSS 22 using the one-way analysis of variance (ANOVA) and LSD statistical tests with the significance level set at 0.05.

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Background and objectives: Diagnosis glucose intolerance in pregnancy is very important in preventing maternal and fetal complications. In this study, we compared hematological and biochemical characteristics of healthy pregnant women and women with gestational diabetes mellitus (GDM) to find predisposing and prognostic variables of GDM.

Methods: In this study, 80 pregnant women (at 24-28 weeks of pregnancy) were divided into a GDM group and non-GDM group by performing oral glucose tolerance test using 75 g glucose according to the International Association of the Diabetes and Pregnancy Study Groups criteria.
Results: The mean age of women with GDM was significantly higher than those without GDM (p=0.048). Other variables including body mass index, gestational age and daily sleep duration did not differ significantly between the two groups (P>0.05). There was a significant association between family history of diabetes and incidence of GDM (p=0.040). In addition, the C-peptide level was significantly higher in pregnant women with GDM (p=0.004).
Conclusion: Considering the role of C-peptide in predicting metabolic syndrome, it is suggested to use this factor for identification of GDM patients.

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Background and objectives: Antibiotic resistance is a global health challenge that affects both individuals and the health system in many ways. The aim of this study was to evaluate the antibiotic resistance pattern in isolates from patients admitted to the intensive care unit (ICU) of a hospital in Qazvin, Iran.
Methods: This descriptive and retrospective study was performed on urine and blood samples collected from 1318 ICU patients in the Velayat Hospital of Qazvin (Iran) during 2017-2019. Data were collected from patients’ medical records. All statistical analyses were performed using SPSS software (version 25).
Results: Based on the findings, 65.2% of the samples were related to urinary tract infections and 34.7% to bloodstream infections. Escherichia coli (68.6%) and Stenotrophomonas (41.0%) were the most common bacteria isolated from urinary tract infections and bloodstream infections, respectively. Moreover, the rate of antibiotic resistance was higher among Acinetobacter, Escherichia coli, Stenotrophomonas, Enterococcus and Pseudomonas isolates.
Conclusion: The rate of drug resistance in isolates from ICU patients is alarmingly high and requires immediate attention. It is recommended to modify antibiotic prescriptions in the hospital based on the results of antibiotic resistance pattern, particularly for treatment of infections caused by E. coli and Stenotrophomonas.

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Background and objectives: Coronavirus disease 2019 (COVID-19) is a global health problem. Laboratory professionals are at a higher risk of contracting the disease during the COVID-19 pandemic. This study was conducted to examine lab professionals' perceptions and satisfaction with organizational processes during the COVID-19 outbreak.
Methods: This cross-sectional survey was carried out on 53 medical laboratory professionals working at laboratories in Tripoli (Libya) between November 2020 and January 2021. Data were collected via face-to-face questionnaire. Responses to questions were scored based on a five-point Likert scale (1=strongly disagree, 2= disagree, 3=neutral, 4=agree and 5=strongly agree). Data were presented as frequency and percentages using the Microsoft Excel 2016.
Results: Most participants were female (81.2%) and with less than five years of work experience (39.6%). The majority of respondents (79.3%) had a bachelor’s degree. Most healthcare workers (75.5%) were unaware whether the lab would provide medical care if they were tested positive for COVID-19, while 13.2% of them perceived that they will get free medical care. Owing to social distancing, 20 subjects (37.7%) felt that their social activities have been altered during break time.  Only 3.7% of the participants believed that their motivation level decreased due to the COVID-19 outbreak.
Conclusion: The outcomes of this study provide laboratorians’ perspective in the COVID-19 crisis as well as specific lessons for future unpredicted crises.

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Background and objectives: In recent years, analytical error rates in medical laboratories have decreased significantly. It has been demonstrated that the majority of errors occur outside of the laboratory in the pre-analytical and post-analytical phases. Our study aimed to evaluate the specimen rejections that occur for various reasons in the central clinical laboratory of a teaching hospital.   
Methods: The study included all specimens (emergency and routine) that were sent from different units of the hospital to the central laboratory between January and December 2019.
Results: Based on the results, 3483 (0.27%) out of 1,307,013 specimens were rejected. The rejection rate was highest for specimens from the intensive care unit (0.69%) and lowest for specimens from the outpatient clinic (0.18%). The specimen rejection rate was 0.42% and 0.22% for specimens from the service unit and emergency department, respectively. The rejection rate for specimens from the intensive care unit was significantly higher than that for specimens from the emergency department (p<0.001), outpatient clinic (p<0.001), and service unit (p=0.010). Although the number of specimens from the intensive care unit was lowest, it had the highest rate of specimen rejection. In our study, most analysis requests were from the outpatient clinic. However, the specimen rejection rate was lowest in this unit.
Conclusion: The results indicate that the reasons for specimen rejection may be influenced by the health status of the patient rather than the patient population.

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Background and objectives: Microscopic agglutination test is the gold standard sero-diagnostic method for detection of leptospirosis. Moreover, it helps identify serovars and their titers in serum samples. For obtaining accurate titer results, proper sampling, collection, storage, and transportation of samples are crucial while maintaining the cold chain. Since storage for long periods and the subsequent deterioration of samples may affect the final titers, we proposed an alternative method of MAT testing using filter paper-dried serum samples. We also evaluated sensitivity and specificity of the MAT test by using filtered-dried serum samples compared with the conventional MAT test.
Methods: This experimental study was performed on human and animal serum samples that were sent to a reference leprospirosis laboratory in 2020. Overall, 142 positive samples (with 289 titers for different strains) and 15 negative samples were used for MAT test using filtered-dried serum. For this purpose, each sample was dried on a filter paper (Whatman 903, GE Healthcare) at room temperature (20-30 °C) and kept for four days. On the fifth day, the filter papers were cut into small pieces, soaked in phosphate buffer saline, vortexed, and slowly mixed on shaker for two hours to elute antibodies. The MAT tests were performed simultaneously and under the same environmental conditions.
Results: The new MAT test using dried serum samples showed 79% sensitivity and 100% specificity. The test also had positive predictive value of 92% and negative predictive value of 24% when compared with the gold standard MAT test.
Conclusion: Filter-dried serum can be used for MAT test to overcome serum storage and transportation problems.

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Background and objectives: Voluntary blood donation is the main source of blood and its components globally. Blood transfusion is essential for management of various diseases but remains as one of the most important causes of disease transmission. In this study, we screened donated blood samplesfor haemoparasites in the University of Calabar Teaching Hospital, Nigeria.
Methods: This cross-sectional study was performed on 200 blood samples taken from donors who had been asymptomatic for haemoparasite infections. The blood samples were analyzed microscopically for the presence of malaria parasites using Giemsa stained thin smears and thick smears. The Knott concentration technique was used to detect microfilaria. To evaluate presence of trypanosomes, triple centrifugation was carried out and the resulting sediment was used to prepare wet and smears stained with 10% Giemsa solution.
Results: The prevalence of malaria parasites, microfilaria, and trypanosome was 38% (76/200), 5% (10/200), and nil (0/200), respectively. The prevalence of malaria infection was highest among females, individuals aged 18–25 years and those with O+ blood type. Most donors had malaria parasite density of 200–4000/µl. Microfilaria was only found in males and more common among subjects between 26 and 33 years of age as well as those with O+ blood type.
Conclusion: The findings revealed the presence of malaria and microfilaria infections and the absence of trypanosomes among blood donors in Calabar, Nigeria. This accentuates the need to screen all blood donors for haemoparasites in order to reduce the spread of the parasites and minimize its effects on the recipients.

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Background and objectives: Garlic is a medicinal plant with various health promoting properties including antimicrobial effects. In this study, we investigated in vitro antibacterial effects of garlic hydro-alcoholic extract against enterohemorrhagic Escherichia coli (EHEC).
Methods: Garlic hydro-alcoholic extract was prepared by maceration method.  Phytochemical analysis of the extract was carried out using gas chromatography-mass spectrometry. Minimum inhibitory concentration (MIC) of the extract against EHEC was determined by micro-dilution assay. Cytotoxic effect of the garlic extract on human colon adenocarcinoma cell line (SW480) was assessed using MTT assay. Micro-dilution assay was also used to determine the MIC of the extract against EHEC when co-cultured with SW480 cells.
Results: The amount of organosulfur in garlic extract was 70.91% and the most common organosulfur compounds were trisulfide, di-2-propenyl (34.8%) and diallyl disulfide (14.83%). The MIC of garlic hydro-alcoholic extract on EHEC alone and when co-cultured with SW480 was 12.5 mg/ml. Concentrations of 12.5 mg/ml and 25 mg/ml of the extract significantly reduced the viability of SW480 cells compared to control and concentration of 6.25 mg/ml of garlic extract (p <0.0001).
Conclusion: The garlic hydro-alcoholic extract has inhibitory effects on EHEC in vitro. Therefore, it can be considered a suitable candidate for controlling infections caused by EHEC.

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Background and objectives: Neutralized electrolyzed water (NEW) is a novel natural disinfectant. It has been suggested that application of NEW can improve the shelf life of fish. This study aimed to investigate effect of NEW incorporated in alginate coating on growth of Escherichia coli O₁₅₇: H₇ on salmon fillets over a period of 12 days.
Methods: Fish fillets were inoculated with E. coli O₁₅₇:H₇ and divided into six different treatment groups: control (no coating), distilled water, alginate, EW, EW & alginate (Samples coated with alginate solution prepared by EW), and EW+ alginate (samples immersed in EW, then coated with alginate solution). The fillets were kept at 4 °C, and the bacterial count was determined on days: 0, 2, 4, 8, and 12. Data analysis was performed using repeated ANOVA and Bonferroni post-hoctest at statistical significance of 0.05.
Results: Treatment with alginate coating and EW alone could significantly reduce E. coli O₁₅₇: H₇ count on the salmon fillets. However, maximum reduction (1.27 log CFU/g) of bacteria was achieved when using alginate coating combined with EW.
Conclusion: According to the results, the combination of alginate coating with EW can be applied as a natural antimicrobial for increasing safety of food products, especially fish, against pathogenic bacteria such as E. coli O157: H7.

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Background and objectives: The incidence of candiduria caused by Candida spp. has increased in recent years, particularly in hospitalized patients. Candiduria is most commonly caused by Candida albicans; however, an increase in the prevalence of non-albicans species has been observed during last decades. This study aimed at molecular identification of Candida species isolated from candiduria in hospitalized patients.
Methods: This cross-sectional study was conducted on 530 hospitalized patients in two hospitals in the Mazandaran Province, Iran. Midstream urine specimens were collected and then cultured on CHROMagar Candida medium. Molecular identification of common Candida species was carried out using the polymerase chain reaction-restriction fragment length polymorphism method after enzymatic digestion with MspI. C. albicans and Candida parapsilosis species complexes were identified by amplification of the HWP1 and intein-containing vacuolar ATPase precursor genes, respectively.
Results: The frequency of candiduria was estimated at 14% among hospitalized patients. Of 74 samples positive for candiduria, 65 (87.8%) were isolated from females. The most common predisposing factor to candiduria was diabetes (n=36; 48.6%). The most frequent isolates were C. albicans complex (n=44; 59.4%), followed by Candida glabrata (n= 16; 21.6%), Candida tropicalis (n= 10; 13.5%), Candida Krusei (n= 3; 4%) and C. parapsilosis (n= 1; 1.3%).
Conclusion:  Based on the results, the conventional and molecular methods produced similar results for identification of Candida species. However, accurate identification of Candida spp. requires the use of molecular techniques such as PCR-RFLP, HWP1, and intein-containing vacuolar ATPase precursor genes. Nevertheless, chromogenic methods such as CHROMagar Candida can be used for diagnosis of Candida spp. in laboratories with limited resources.

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Background and objectives: Developing scaffolds is important for tissue engineering and repairing damaged tissues. The present study aimed to investigate effects of pre-incubation of an electrospun silk fibroin scaffold in complete and serum-free media on proliferation and survival of cells seeded on the scaffold.
Methods: After removing sericin from the silk cocoon and preparing the fibroin solution (3% w/v), the electrospun silk fibroin scaffold was fabricated and its morphology was evaluated by scanning electron microscopy. The scaffolds were pre-incubated in complete and serum-free Dulbecco's Modified Eagle media for one hour (short-term) and 10 days (long-term), and the hydrophilicity of scaffolds was evaluated by measuring the water contact angle. Rat bone marrow mesenchymal stem cells were seeded onto the scaffolds, and cell survival and genomic DNA concentration were evaluated after 21 days.
Results: The short-time pre-incubation of electrospun silk fibroin scaffolds in the complete medium increased the proliferation of seeded cells because of serum protein adsorption. In addition, long-term pre-incubation of the scaffolds in the complete and serum-free media increased cell proliferation due to the increased hydrophilicity of the scaffold (p<0.05). However, only long-term pre-incubation of the scaffolds in the complete medium had a significant effect on cell survival.
Conclusion: The results demonstrated that long-term pre-incubation of the scaffolds in the complete medium have more profound positive effects on cell survival and proliferation compared to short-term pre-incubation.

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Background and objectives: Hypertension is associated with vascular remodeling, which is supported by the protein disulfide isomerase A1 (PDIA1). Exercise training has beneficial effects on vascular function in subjects with hypertension. Alpha lipoic acid (ALA) is a powerful biological antioxidant. However, the role of exercise training and ALA on PDIA1 are not well understood. The aim of the present study was to investigate effects of training with different intensities and ALA supplementation on PDIA1 expression in cardiomyocytes of hypertensive rats.
Methods: In this experimental study, 35 male Wistar rats (age: eight weeks, weight: 190-220 g) were randomly divided into seven groups: control, hypertensive, hypertensive+ALA, hypertensive+high intensity interval training (HIIT), hypertensive+moderate-intensity training (MIT), hypertensive+HIIT+ALA, and hypertensive+MIT+ALA. Hypertension was induced by three weeks of L-NAME administration (40 mg/kg/day). The HIIT and MIT protocols was performed five days a week for six weeks. The HIIT protocol consisted of 10 bouts of four minute-running at 80–85% of Vmax, and the MIT protocol consisted of 13 bouts of four minute-running at 55–60% of Vmax. In the supplementation groups, 20 mg/kg of ALA was administered orally once a day. Immunohistochemistry staining was used to study protein expression.
 Results: Induction of hypertension significantly decreased PDIA1 expression compared to the control group (p=0.001). Moreover, PDIA1 expression increased significantly in the hypertensive+ALA (p=0.023), HIIT (p=0.001), MIT (p=0.007), MIT+ hypertensive+ALA (p=0.0001) and HIIT+ hypertensive+ALA (p=0.0001) group compared to the control group.
Conclusion: Hypertension is associated with decreased cardiac PDIA1 level, and both HIIT and MIT along with ALA supplementation are effective in increasing cardiac PDIA1 expression in hypertension.

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Background and objectives: Bacteriocins are generally active antimicrobial peptides effective against bacteria closely related to the producer. Escherichia coli produce two bacteriocins: colicins and microcins. Microcin J25 (Mcc J25) is an antibacterial peptide that inhibits bacterial transcription by disrupting the nucleotide-uptake channel of bacterial RNA polymerase. The objective of this study was to evaluate antimicrobial activity of MccJ25 produced by the bacteriocinogenic E. coli.
Methods: In this experimental study, 120 clinical specimens were selected from private diagnostic laboratories in Isfahan (Iran) in 2020. Antagonistic activity of isolates was tested by adopting agar plug method. Total DNA was extracted from clinical specimens and polymerase chain reaction (PCR) was performed using specific primers for amplification of the complete sequence of MccJ25 gene. Accuracy of the PCR products was confirmed by direct sequencing. Homology analysis was performed by using BLAST. Data were analyzed with Chromasv2.1.1 software.
Results: Overall, 120 E. coli strains were isolated from the clinical specimens. The antibiotic activity of Mcc J25 was mainly directed at Enterobacteriaceae, including several pathogenic E. coli strains of which 25 had positive well test samples, and about 5 (20%) of the collected clinical samples that were infected with E. coli had the MccJ25 gene.
Conclusions: Based on the results, Mcc J25 has favorable antibacterial potential, which can be further exploited as an alternative to chemical antibiotics.

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Background and objectives: Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease caused by the accumulation of large amounts of fat in the hepatocytes. Given that atorvastatin is effective for treatment of NAFLD, the present study investigated effects of high-fat/fructose diet (HFFD) with atorvastatin on liver enzymes and lipid profile in a NAFLD rat model.
Methods: Thirty-two male Wistar rats were divided into four groups: 1) normal control, 2) HFFD control, 3) HFFD + atorvastatin, and 4) normal + atorvastatin. The groups received HFFD for 15 weeks to induce hepatosteatosis. Atorvastatin was administrated at the dose of 10 mg/kg/day. Lipid profile and liver enzymes were measured after eight weeks of intervention.
Results: Triglyceride, cholesterol, gamma-glutamyl transferase, and aspartate transaminase were significantly reduced in the HFFD + atorvastatin group compared with the HFFD control group. In addition, cholesterol, high-density lipoprotein, alkaline phosphatase, and gamma-glutamyl transferase were significantly increased in the normal + atorvastatin group compared with the normal control group. Low-density lipoprotein increased significantly in the HFFD + atorvastatin group and the normal + atorvastatin group compared with other groups. There was a significant difference in the alanine transaminase levels between the groups taking atorvastatin. In fact, alanine transaminase level was lowest in the normal + atorvastatin group.
Conclusion: Atorvastatin improves the lipid profile and fatty liver and controls liver enzymes. Therefore, it can be used with caution to improve the lipid profile and reduce the complications of NAFLD.

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Background and objectives: Soft tissue is a non-epithelial extraskeletal tissue of the body. Soft tissue tumors (STTs) are the most commonly diagnosed neoplasms. Fine needle aspiration cytology (FNAC) is minimally invasive, quick, and a definitive diagnostic modality. Biopsy for histopathology is the gold standard method for diagnosis but is invasive. The aims of this study were to determine the utility of FNAC in the diagnosis of STTs and correlate it with histopathology and to evaluate factors that cause discrepancies between FNAC and histopathology.
Methods: This retrospective, record-based study was done on STTs received for FNAC and histopathology examinations at the Department of Pathology, MIMS, Mandya from January 2018 to June 2021.
Results: A total of 74 cases of FNAC with histopathological correlation were available. Seventy one cases (95.9%) were benign and three (4%) were malignant according to FNAC. Discordance was seen in one case of low grade myxofibrosarcoma, which was diagnosed as benign spindle cell tumor on FNAC. The sensitivity, specificity, positive predictive value, and accuracy of FNAC in diagnosing malignancy were 75%, 100%, 100%, and 98.6%, respectively.
Conclusion: Our findings indicate that FNAC is beneficial preoperatively as it differentiates between benign and malignant lesions in most cases. In the case of low grade myxofibrosarcoma, bland tumor cells led to a benign diagnosis on FNAC, but histopathology allowed sampling of a larger area of the tumor and the right diagnosis was made. Biopsy is the gold standard, but FNAC has high specificity in diagnosing malignant tumors and prevents unnecessary extensive, radical surgery for benign lesions.

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Background and objectives: Echinococcosis is a global cosmopolitan zoonotic disease and a major veterinary and public health issue. In humans, echinococcosis usually develops following close contact with infected dogs or ingestion of the parasite eggs. Until now, no effective vaccine has been commercially developed, and treatment is only focused on controlling hydatidosis. This study was conducted to evaluate the protoscolicidal activity of alcoholic extracts of pomegranate rind and barberry.
Methods: The alcoholic extracts of pomegranate rind and barberry were prepared by mixing 330 g of powdered plants with 1,000 ml of 70% ethanol. A concentrate of viable protoscolices (PCSs) was obtained from hydatid cysts found in the lungs and liver of sheep. Next, PCSs were treated with four different concentrations (5, 10, 20, 30, and mg/ml) of each extract for 10, 20, 30, and 60 minutes. The eosin exclusion test was performed to assess viability of the PCSs.
Results: The mortality rate caused by treatment with the extracts ranged between 25% and 100%. Complete inactivation of PCSs was achieved after 60 minutes of exposure to 15 mg/ml of the pomegranate rind extract and 30 mg/ml of the barberry extract.
Conclusion: Given their favorable anti-PCSs activity, combination of conventional synthetic albendazole with the alcoholic extracts of pomegranate rind and barberry might induce higher anti-PCS activity with lower side effects. It is recommended to evaluate the anti-PCSs activities of the pomegranate rind and barberry alcoholic extracts in vivo and ex vivo.

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Background and objectives: Aflatoxin B1 (AFB1) is the most toxic aflatoxin produced by a large number of Aspergillus species. Successful detoxification of this toxin is an important attempt to improve community health. The aim of this study was to evaluate reducing effects of yeasts isolates from kefir and traditional kefir-like fermented beverages on AFB1 in a broth medium.
Methods: Polymerase chain reaction-sequencing was carried out to identify the yeast isolates from kefir and kefir-like beverages. Effects of the isolates on AFB1 adsorption and biotransformation in peptone dexterose broth medium were evaluated by using high performance liquid chromatography.
Results: Saccharomyces cerevisiae and Kluyveromyces marxianus were isolated from kefir and kefir-like beverages and resulted in 46% and 53% AFB1 adsorption, respectively. The isolates 27Y and 2Y caused 7% toxin biotransformation, while 10% toxin biotransformation was achieved by the isolate 18Y. 
Conclusion: Our results indicate that the yeast isolates from kefir and traditional kefir-like products can bind to and detoxify AFB1, thereby reducing its harmful effects.

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Background and objectives: Human Dermal Fibroblasts (HDF) are involved in the production of the extracellular matrix, formation of the connective tissue, and wound healing. Considering the role of ciprofloxacin in the treatment of skin infections and the subsequent oxidative stress as well as the protective effects of vitamin E and low power laser against inflammation and oxidative stress, we evaluated combined effects of low power laser and vitamin E on inflammation and oxidative stress in HDF cells treated with ciprofloxacin.
Methods: Morphology of the cells was studied using an inverted microscope. Viability of the cells was assessed using the MTT assay, and the concentration of reactive oxygen species was determined after exposure of the cells to ciprofloxacin (5, 25, 50, 75, and 100 μg/ml), vitamin E (1 mg/ml), and low power laser (660 nm; power density: 30 mW.cm⁻²).
Results: The survival rate of the cells increased significantly after the treatment with ciprofloxacin, vitamin E, and low power laser compared with the cells treated with ciprofloxacin and vitamin E (p<0.001). The amount of reactive oxygen species increased in the treated cells when compared with those only treated with ciprofloxacin and vitamin E.
Conclusion: The low power laser treatment has favorable effects on the growth of HDF cells, which can be beneficial for wound healing, even in the presence of ciprofloxacin.

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Background and objectives: In recent years, exercise immunology studies have focused on key components of immune function, such as immune cells, immunoglobulins, and messenger molecules, as well as the effects of environmental and exercise factors. The aim of this study was to evaluate effects of 8 weeks of selected training on serum levels of interleukin (IL)-4, IL-6, and motor performance in elite water polo players.
Methods: For this purpose, 20 male water polo players (mean age: 23 years) were randomly divided into an experimental group (n=10, selected water polo training) and a control group (n=10, traditional water polo training). The selected water polo training was performed for 8 weeks, 6 sessions per week. The intensity of training was controlled using maximum heart rate (80-100%) and increased by 5% every week. Water polo performance tests included a record of 50 meters swimming, 100 meters high swimming, 200 meters’ breaststroke, 6 ×50 meters swimming, and 400 meters swimming. To evaluate the serum levels of IL-6 and IL-4, venous blood (5 ml) was taken in the pretest and posttest stages. The serum levels of IL-4 and IL-6 were measured by sandwich enzyme-linked immunosorbent assay. Mean values were compared using the t-test, at significant level of 0.05.
Results: The selected water polo training significantly changed IL-4 levels in elite water polo players (p<0.05). However, IL-6 levels and performance of the subjects did not change significantly.
Conclusion: The selected swimming exercises could relatively improve swimming stagnation of water polo players. However, due to the limited knowledge in this regard, there is a need for further research.