فصلنامه پاتوبیولوژی مقایسه ای
سال هفدهم شماره 70 (زمستان 1399)

Ice cream as a popular dairy product used in summer, due to its unique physical and chemical nature, is a suitable environment for growth of microorganisms. Therefore, the aim of this study was to investigate the level of microbial contamination of traditional ice creams provided in East Azarbaijan province. In this study, microbial contamination of the traditional ice creams provided in East Azerbaijan province during 2018-2019 was investigated. A total of 274 ice creams were randomly collected from ice cream supply centers and studied to identify coagulase-positive Staphylococci, Escherichia coli, Salmonella, and total microorganism and Enterobacteriaceae count according to the Iranian National Standard. All tests were cultured according to the Iranian National Standard and were identified and counted by confirmatory tests. A total of 234 samples (85.4%) were not usable, according to the standard limit reported by the Iranian standard Department. In 18.2% and 10.9% of the samples, coagulase-positive Staphylococci and E. coli were isolated, respectively. In addition, 72.2% and 80.2% of the samples, showed the total Enterobacteriaceae and total microorganism count of higher than the limits, respectively. None of the samples were infected with Salmonella. The results showed a high microbial contamination of the studied samples. Accordingly, applying strict standards by the relevant organizations associated with food production, and also providing strict hygiene supervision and a comprehensive control over all stages of ice cream production are essential. The results also indicated the need for health education for ice cream makers.

Trichophyton rubrum and Trichophyton mentagrophytes are important causes of human and animal skin infections that cause infection by expressing pathogenic genes. The aim of this study was to investigate the presence and role of pathogenic genes in the pathogenesis of these fungies. In this study, 48 approved samples were obtained from the mycology collection of Pasteur Institute of Tehran. The fungies were grown in specific media and differential tests were performed for both dermatophytes. DNA extraction was performed using a special kit. Multiplex PCR was performed using specific primers to evaluate the presence of target genes. The results obtained from Multiplex PCR showed that in the studied strains mep4 and mep1,2,4 showed the highest presence in Trichophyton rubrum and Trichophyton mentagrophytes, respectively. The results of Multiplex PCR for ScpA, B and Np genes indicated that NP gene was present in approximately 80% of both dermatophyte strains. The presence of ScpA gene was observed in 6 strains of Trichophyton rubrum and 14 strains of Trichophyton mentagrophytes. The data of this study confirmed the synergistic effect of pathogenic genes in the pathogenesis process. The present study also proved that the Multiplex PCR method is an accurate and precise method that can increase the chances of treatment in patients with this disease by significant reducing the time of diagnosis of dermatophytosis.

Citrinine is a nephrotoxic metabolite that damages the kidneys in animals. Therefore, the development of detoxification methods during the food process is important. Quantum devices, using a single source of excitation, are excited by individual wavelengths and produce different emission peaks. In this study, a new bioconjugation-based sensor consisting of quantum dot semiconductor nanocrystals and anti-citrinin antibody was used to determine the amount of citrinin toxins using the FRET (Fluorescence Resonance Energy Transfer) system. Semiconductor nanocrystals or quantum materials (CdTe, CdTe / CdS) were synthesized in the laboratory using reflux method by reducing tellurium powder under a stream of nitrogen gas. The fluorescence intensity of quantum data was determined using a spectrofluorimetric device. Antibody activity in nanobioconjugate was also measured by spectrofluorimetry. The citrinin-albumin conjugate was then attached to the fluorescence compound rhodamine 123, which is a highly affinity immunological reaction between the anti-citrinin-quantum antibody (donor) and the citrinin-rhodamine 123 (receptor) label used as fluorophora. After adding the nanobioconjugated solution to the cuvette, which contains a certain amount of phosphate buffer, citrinin was added to it in different concentrations, and after a few minutes, changes in the intensity of quantum dot fluorescence were observed. A regular decrease in fluorescence intensity was obtained by increasing the citrinin concentration. Due to the collective effects of mycotoxins on human and animal health, it is better to determine the extent of food contamination with mycotoxins, including citrinin, using nanobiosensors as a specific method that results from the use of monoclonal antibodies. Unlike conventional methods such as ELISA and HPLC, these designed nanobiosensors are homogeneous, simple, fast, and inexpensive and do not require much separation or rinsing.

Due to the side effects of chemical drugs in pain relief, the use of herbal medicines is increasing. Red algae have antioxidant, antibacterial, antifungal, antitumor, and antimicrobial properties. The present study aimed to investigate the effect of Red Algae ethanolic extract and its possible neural interactions on formalin-induced pain in mice. 125 adult male mice allocated in 6 experiments. In the first experiment, mice were injected intraperitoneally with saline, red algae extract (2.5, 5, and 10 mg/kg), and morphine (5 mg/kg). In the second experiment, mice received intraperitoneal injections of saline, red algae extract (10 mg/kg), naloxone (non-selective opioid antagonist, 2 mg/kg), and naloxone + red algae extract. Experiments 4 to 6 were similar to the second experiment but injected with flumazenil (non-selective GABA receptor antagonist, 5 mg/kg), cyproheptadine (non-selective serotonin receptor antagonist, 2 mg/kg), chlorpheniramine (histamine H1receptors antagonist, 20 mg/kg) and cimetidine (histamine H2receptors antagonist, 12.5 mg/kg) were used instead of naloxone. After 30 minutes, subcutaneous injection of formaldehyde was performed on the plantar surface of the right foot, and the time of licking, chewing, and biting (Licking Time) was measured. According to the results, morphine significantly reduced pain time compared to the control group (P<0.05). Red algae extract in a dose-dependent manner reduced pain compared to the control group (P<0.05). Injection of naloxone + red algae extract significantly reduced the analgesic effects of red algae extract compared to the group of red algae extract (P<0.05). Flumazenil + red algae extract significantly reduced the analgesic effects of red algae extract (P<0.05). Injection of cyproheptadine + red algae extract significantly enhanced the analgesic effects of red algae extract (P<0.05). Injection of chlorpheniramine + red algae extract significantly reduced the analgesic effects of red algae extract (P<0.05). The results showed that the analgesic effects of red algae are mediated by opioidergic, serotonergic, GABAergic and histaminergic pathways.

Leishmania infantum parasite is the main causative agent of visceral leishmaniasis (VL) which threatens a wide range of humans and dogs in Iran. Our objective was to investigate Leishmania parasite species in Ardebil Province a well-known VL foci targeting ITS-rDNA gene, sequencing and phylogenetic analysis. Vacuum EDTA tubes were used for blood collection of asymptomatic dogs using non-invasive methods in Ardabil, northwestern Iran in August 2019. Phenol-chloroform DNA extraction, ITS-rDNA gene PCR and sequencing were performed. Leishmania species was accurately identified based on sequences and Maximum likelihood phylogenic analyzes. 11 of 31 asymptomatic dogs were definitively infected with L. infantum. Under 5 years old age group had the highest infection rate, which showed that this group is more sensitive to VL in this area and also the infection was mainly observed in male sheepdogs. These findings show that non-invasive sampling and molecular methods are reliable and convenient in the diagnosis of visceral leishmaniasis. Regarding the 35.5% infection ratio in the area control and monitoring measures of human individuals and canine reservoirs should be taken to consideration.

Anaplasmosis, babesiosis and theileriosis is parasitic diseases that can cause significant damage to the livestock industry. Despite the importance of the pathogenicity of theileriosis, babesiosis and anaplasmosis in large animal populations, in Iran, studies have been performed mainly on small ruminants. So, the aim of this study was to the diagnosis of the frequency of Theileria, Babesia and Annapalsma infections from cattle in Alborz province using microscopic examination and PCR (Polymerase Chain Reaction). For this purpose, out of 130 dairy cattle were taken blood samples and stained with Giemsa dye. Positive smear samples were incorporated for molecular detection. DNA was extracted from blood samples with phenol-chloroform and performed PCR using 18S rRNA, 16S rRNA and TamS primers to identify of the genus and species. The results of this study showed that frequency of piroplasmic form was observed in 9.23% of cases. The 18S rRNA PCR findings revealed 5.38%, were confirmed infection with Theileria and Babesia. Also, Tams1 PCR results were indicated Theileria anulata infection in all cases. 16S rRNA PCR was detected in 3.85% for Anaplasma. No case of Babesia was observed. Considering the cases of infection with T. anulata and Babesia and the importance of some species of Babesia, the importance of further studies to evaluate these diseases in order to improve the livestock industry seems necessary.

One of the most important metabolic abnormalities in the early lactation period is ketosis. The gold standard test for the diagnosis of ketosis is the measurement of beta-hydroxybutyrate (BHB) in the blood. In this study, the diagnostic value of the electronic ketone meter, Novavet, for diagnosing cows with ketosis was evaluated in comparison with the standard laboratory method. Blood samples were taken from 68 cows in the period of 7-14 days after calving. In the laboratory, serum BHB was measured by spectrophotometry and Randox kit.  At the time of blood sampling, the amount of BHB in whole blood was determined with ketone meter in the same cows. BHB values obtained from the two methods were analyzed by T-test and Pearson correlation statistical models. In order to determine the best cut points of BHB using Novavet machine, which can make the best distinction between healthy and ketosis cows (based on reference test), also to estimate the sensitivity and specificity of Novavet, the ROC analysis is used. The amount of BHB in whole blood in the manual method is significantly higher than the laboratory method. However, there is a significant and good correlation between these two methods. Also, Novavet at the cut point of 1.2 mmol/l has the highest combination of sensitivity and specificity (100 and 41.9%) compared to the standard test. Due to the good and significant correlation between the Novavet test and its high sensitivity, it can be said that this method has an acceptable accuracy for diagnosing hyperketonemic cows.