ABSTRACT
       Background and objectives: Contamination of food products with mycotoxins is a public health problem. The International Agency for Research on Cancer has identified mycotoxins as hepatotoxic and carcinogenic agents to humans (Group 1). The Kurdistan Province is the ninth largest producer of wheat in Iran. We aimed to determine the level of contamination with total aflatoxin (TAF), aflatoxin B₁ (AFB₁) and ochratoxin A (OTA) in 66 wheat samples randomly selected from 11 wheat flour factories in spring and summer.
       Methods: The level of toxins was measured by microtiter plate enzyme-linked immunosorbent assay (ELISA) using a microtitre plate ELISA reader and total AF, AFB₁ and OTA commercial kits.
      Results: Overall, the level of TAF and AFB in 16.67% of the samples exceeded the maximum tolerable limit set by the Institute of Standard and Industrial Research of Iran (ISIRI). However, the level of OTA contamination did not exceed the maximum tolerable limit set by the ISIRI. In addition, the level of TAF, AFB₁ and OTA exceeded the maximum tolerable limit set by the EU in 68.18, 90.91 and 36.36% of the samples, respectively. The level of contamination with these mycotoxins differed significantly in spring and summer (P<0.05).
      Conclusion: The level of mycotoxin contamination in wheat samples produced in the Kurdistan Province is alarmingly high and appropriate measures should be taken to eliminate the causes of this issue.
         KEYWORDS: Aflatoxin, Aflatoxin B_1, Ochratoxin A, Wheat, ELISA.

ABSTRACT
         Background and Objectives: Elevated blood lipid levels are correlated with risk of cardiovascular disease, especially in overweight individuals. The beneficial effect of strength training on lipid profile has been well documented. However, the effect of strength training with flow blood restriction has not been established. The purpose of this study was to compare the effect of eight weeks of strength training with and without blood flow restriction on some of the cardiovascular risk factors in overweight females.
         Methods: In this study, 28 overweight females aged 18 to 24 years were randomly assigned into three groups of blood flow restriction strength training (BFRT), traditional strength training (TRT) and control. Participants in the BFRT group performed eight weeks of strength training three sessions per week at 30% of 1-repetetion maximum, while participants in the TRT group performed the training at 65-80% of 1-repetetion maximum. Cardiovascular variables, systolic blood pressure and diastolic blood pressure were measured before and after the exercise training. Data was analyzed using descriptive statistics, paired t-test and one-way analysis of variance.
          Results: Triglyceride level decreased significantly in the BFRT (p=0.022) and TRT (p=0.038) groups compared with the control group. Moreover, there were no significant differences in the body mass, waist-to-hip ratio, body mass index, high-density lipoprotein, low-density lipoprotein, and cholesterol levels between the study groups (P≥0.05).
           Conclusion: Our findings suggest that the BFRT and TRT may not be suitable for preventing or even reversing the physiological changes induced by obesity.
         Keywords: Resistance Training, Lipids, lipoprotein, overweight.

ABSTRACT
           Background and Objectives: Local cheese made from raw milk is one of the most commonly consumed dairy products in the world. Mycotoxin contamination of foodstuff and its transmission to consumers are extremely important public health issues. The purpose of this survey was to determine the level of aflatoxin M1 (AFM1) residues in Koupeh cheese, a traditional fermented Iranian cheese produced in spring and summer.
           Methods: We randomly collected 48 local cheese samples produced in Mahabad (northwest of Iran) during spring and summer. The level of AFM1 was measured by enzyme-linked immunosorbant assay using commercial kits and a microplate reader.
           Results: All samples contained measurable amounts of AFM1. Cow milk cheese samples contained higher level of AFM1 compared to sheep milk cheese samples. The level of AFM1 in the samples from both animals was lower in summer. There was no significant difference between the mean level of AFM1 in summer and spring. Moreover, 33.3% of cow milk cheese samples collected in spring and 16.6% of the samples collected in summer contained toxin levels higher than the maximum allowed concentration set by the European Commission (250 ng/Kg) and by the Institute of Standards and Industrial Research of Iran (200 ng/Kg).
           Conclusion: The results of this study show that the level of AFM1in Koupeh cheese is influenced by the livestock type and production season, in a way that the level of contamination is higher in spring.
           Keywords: Cheese, Cultured Milk Products, Aflatoxin M1, ELISA.

ABSTRACT
         Background and Objectives: Silver nanoparticles (AgNPs) have physical and surface properties that could threaten human and environmental health. AgNPs are classified as ‘very toxic’ to eukaryotic organisms and are less toxic to bacteria. The aim of the present study was to study the effects of different sub-minimum inhibitory concentrations (MICs) of AgNPs on some virulence factors of Staphylococcus aureus as a pathogenic bacterial model.
         Methods: Tube double serial dilution method was used to determine MIC of AgNPs against standard strain and ten field isolates of S. aureus. Tube cultures of isolates in LB broth were supplemented with different concentrations of AgNPs and were incubated at 37 °C with constant shaking under aerobic conditions. Samples from each tube were streaked on blood agar plates and assay for hemolysins, coagulase and DNase production were performed.
         Results: The MIC of AgNPs against all examined isolates was determined as 50 µg/mL. The results showed that 1/2, 1/4 and 1/8 MIC of AgNPs had no negative effect on DNase and coagulase production but inhibited alpha- and beta-hemolysin production in most isolates (64-91%). In addition, production of delta-hemolysin was inhibited by 1/2 MIC of AgNPs.
         Conclusion: The effects of sub-MIC of AgNPs on bacterial growth appear at 4-8 hours post-exposure and then the bacteria follow a normal growth trend. This toxic effect may affect ecosystems species.
         Keywords: Silver particles, Minimum inhibitory concentration, Virulence factors, Staphylococcus aureus.

ABSTRACT
             Background and Objectives: Efflux-based systems may play a role in resistance to fluoroquinolones in Gram-negative pathogenic bacteria. Extracts of some medicinal plants contain molecules that can act as efflux pumps inhibitors. In this study, we aimed to evaluate antibacterial activities of ethanolic and chloroform extracts of Cinnamomum zeylanicum and their possible synergistic activity with ciprofloxacin against some Gram-negative pathogenic bacteria. We also analyzed the extracts for presence of efflux pump inhibitors against the examined bacteria.
             Methods:  Powdered dried leaves and branches of C. zeylanicum were extracted with ethanol (85%) and chloroform by the maceration method. Minimum inhibitory concentrations of the extracts alone or combined with ciprofloxacin and phenylalanine-arginine β-naphthylamide (an efflux pump inhibitor) were determined against Pseudomonas aeruginosa, Acinetobacter bummani, Escherichia coli and Salmonella enteritidis using the double serial microdilution method.
             Results: The extracts of C. zeylanicum inhibited the growth of all studied bacteria. Synergistic effects were noted between the extracts and ciprofloxacin against all tested bacteria other than P. aeruginosa. Ciprofloxacin efflux pumps in E. coli, S. enteritiditis and A. baumannii were inhibited by the extracts of C. zeylanicum.
             Conclusion: The extracts of C. zeylanicum could be used as ciprofloxacin-potentiating agents against some Gram-negative pathogens.
             Keywords: Anti-bacterial agents, Cinnamomum zeylanicum, Bacterial pathogens, Efflux pumps.

ABSTRACT
            Background and Objectives: Vitamin D is an essential secosteroid that plays a crucial role in the homeostasis of a few mineral elements, particularly calcium. Since vitamin D deficiency and thyroid diseases are two important global health problems, we aimed to investigate a possible relationship of vitamin D and calcium levels with hypothyroidism in an Iranian population.
            Methods: This case-control study was conducted on 175 subjects with hypothyroidism (75 males and 100 females) and 175 euthyroid controls (85 males and 90 females) who were referred to a laboratory in Gorgan, Iran. Serum levels of 25-hydroxyvitamin D, calcium, thyroid-stimulating hormone (TSH), free triiodothyronine (free T3) and thyroxine (total T4) were measured in all participants.
            Results: Vitamin D and calcium were significantly lower in patients with hypothyroidism (P<0.0001). Free T3 and calcium levels differed significantly among hypothyroid patients based on their vitamin D status (P<0.0001), but vitamin D levels were within sufficient range in all groups. Moreover, there was a positive correlation between free T3 with vitamin D (r= 0.337, P<0.0001) and calcium (r= 0.361, P<0.0001) levels.
            Conclusions: Our results suggest that there may be a relationship between decreased vitamin D levels and thyroid function parameters.
            Keywords: Vitamin D Deficiency, Hypocalcemia, Hypothyroidism, Thyrotropin, Thyroxine.

ABSTRACT
           Background and Objectives: Probiotics are live microorganisms that function through  various mechanisms  and affect the alteration of the commensal microbiota against pathogens. Nowadays,  given the problems associated with antibiotics use, probiotic strains  offer a novel and  appropriate  alternative for the treatment of diseases such as diarrhea. The aim of this study was to investigate the antibacterial synergism of Lactobacillus spp., Bifidobacterium spp. and Escherichia coli strain Nissle 1917 (ECN) on the clinical sample of diarrheagenic E.coli and Campylobacter jejuni.
           Methods: A paper disk-diffusion technique was used to evaluate the antibacterial activity. Sterile 6 mm paper disks were saturated with probiotic suspensions made by settling probiotic medications into distilled water. Three kinds of disk were prepared. One disk was prepared for Lactobacillus spp. and Bifidobacterium spp., another for ECN, and the third was made by combined probiotics. Clinical samples of diarrheagenic E.coli and Campylobacter jejuni were cultivated on Muller Hinton agars, and disks were placed on the inoculated Muller Hinton agars. All plates were incubated under microaerophilic and appropriate conditions.
           Results: The zone of inhibition (ZOI) of the bacterial growth was measured. All pathogenic microorganisms showed sensitivity to the probiotic disks. The combined disks had better effects against pathogens compared with single disks.
           Conclusion: A considerable synergistic effect was observed in the results of combined probiotics; therefore, combined strains can be more efficient against intestinal pathogens in comparison with single probiotics.
           Keywords: Probiotic, Lactobacillus, Bifidobacterium, Escherichia coli Nissle, Diarrhea, Campylobacter jejun.i.

 

Background: Acute ischemic stroke occurs when blood clots obstruct blood vessels within the brain. Platelets (Plts) are integral to the pathophysiology of stroke. This research aimed to explore the relationship between Plt quality and Plt indices in the context of acute ischemic stroke.
Methods: This cross-sectional investigation involved 100 patients diagnosed with acute ischemic stroke at Kosti Teaching Hospital and Alyammama Hospitals. The diagnosis was confirmed using brain CT imaging and electrocardiography (ECG). Blood samples were collected in EDTA-containing tubes within 24 hours following the commencement of treatment and were subsequently analyzed for Plt count, mean Plt volume (MPV), Plt distribution width (PDW), and plateletcrit (PCT) utilizing a hematological analyzer. Data were analyzed using GraphPad Prism software.
Results: Platelet counts negatively correlated with PDW [r=-0.074, P=0.459; R=-0.023, P=0.815], MPV [r=-0.130, P=0.194; R=-0.081, P=0.417], and diastolic blood pressure [r= -0.023, P=0.818; R= -0.024, P=0.805]; and positively correlated with PCT [r= 0.103, P=0.308; R=0.143, P=0.155] and diastolic blood pressure [r=0.022, P=0.823; R= 0.008, P=0.932]. Moreover, PDW positively correlated with systolic blood pressure [r=0.105, P=0.298; R= 0.147, P=0.148] and diastolic blood pressure [r=0.146, P=0.145; R=0.173, P=0.084]. Based on Spearman but not Pearson correlation, PDW showed a negative correlation with PCT [r=-0.005, P=0.959; R=0.010, P=0.929].
Conclusion: The study shows a correlation between Plt count and indices in ischemic stroke patients. The research also presented evidence concerning the relationship between diastolic and systolic blood pressure and Plt counts and indices.