The purpose of the present study was to investigate the antibiotic resistance of culturable bacteria following the increase of three commonly used antibiotics in three agricultural, rangeland, and mine soils with different amounts of heavy metals.Antibiotics amoxicillin, cefixime, and metronidazole were used in amounts of 100 and 200 mg per kilogram of agricultural, rangeland, and mine soils. Then, in a short time incubation (zero, 1, 3, and 7 days), the abundance of bacteria in nutrient agar medium and the percentage of resistant bacteria in nutrient agar medium with antibiotics (16 µg of amoxicillin, 2 µg of cefixime, 8 µg of gentamicin, 16 µg of metronidazole and 8 µg of tetracycline per milliliter of nutrient agar) were counted and estimated.The percentage of bacteria resistant to cefixime, gentamicin, and tetracycline in mine soil, especially rangeland soil, which had high contamination with heavy metals, was higher than in agricultural soil, and only the percentage of bacteria resistant to amoxicillin and metronidazole was higher in agricultural soil than mine soil. In rangeland soil, 100% of bacteria were resistant to the tested antibiotics except for tetracycline. Treatment of soils with amoxicillin caused an increase in the number of resistant bacteria, which was especially evident in agricultural soils at a concentration of 200 mg.kg-1. The same finding was also seen in the application of cefixime, but in mine soil, the high concentration of this antibiotic showed a decrease, and the percentage of resistant bacteria in both rangeland and agricultural soils was close to 100%, but in mine soil, it reached less than 20%. There was a significant increase in the number of resistant bacteria in the soils treated with metronidazole compared to control soils. But, in this treatment, the response of agricultural soil bacteria to a concentration of 200 mg.kg-1 was decreased, and mine soil did not show such a response.In all treatments, the bactericidal power of tetracycline and then gentamicin in the concentrations used in the culture medium was higher compared to the three antibiotics of amoxicillin, cefixime, and metronidazole. Antibiotic resistance of soil bacteria is dependent on soil contamination with heavy metals and diversity of soil bacteria, genetic pool, and ability to move resistance genes between them. The increase of antibiotics in the soil, depending on the characteristics of the soil and the antibiotic causes the dominance of special and resistant species, which increases the transfer of resistance genes and their abundance in the environment.IntroductionAntibiotics are widely used in medicine, agriculture, and animal husbandry. The continuous increase of antibiotics in dry and wet ecosystems causes chemical pollution, and the emergence and spread of antibiotic stability genes and antibiotic-resistant bacteria. The spread of antibiotic resistance is a global threat to human health. Bacteria with various mechanisms can remain stable against antibiotics and at the same time against heavy metals. Although antibiotic resistance can occur naturally, biocontaminants, such as metals (and metalloids), can increase the development of antibiotic resistance by stressing bacteria through the co-selection of genes and traits that protect bacteria from both antibiotics and metals. Many studies have shown that metal pollution has a positive correlation with antibiotic stability genes in polluted habitats. In most of the studies, it has been stated that heavy metals can affect the abundance of antibiotic stability genes in the habitat. This research was conducted with the aim of investigating the transformation of the percentage of stable soil bacteria in the face of different concentrations of antibiotics in soils with different sizes of heavy metals. Materials and MethodsThree commonly used antibiotics, amoxicillin (betalactam), cefixime (cephalosporin), and metronidazole (nitroimidazole) were purchased from Hamedan pharmacy. In the beginning, the tablet and the contents inside the capsule (amoxicillin capsule (500 mg), cefixime tablet (400 mg) and metronidazole tablet (500 mg)) were weighed for all three antibiotics, and the equivalent weight of the pure substance of the antibiotic was obtained. After that, the required weight was used to prepare solutions with a concentration of 100 and 200 mg of the antibiotic per kg of dry soil.Aqueous solutions of three antibiotics, amoxicillin, cefixime, and metronidazole, were added separately to the equivalent weight of dry soil and mixed well. Then sterilized distilled water was added to the soil samples to make the soil moisture close to the agricultural capacity. The treated soil samples were kept in the dark and at laboratory temperature (about 25°C). Then, at four heating times of zero (without heating), 1, 3, and 7 days, the abundance of bacteria in nutrient agar cultures without antibiotics and nutrient agar with 5 antibiotics amoxicillin, cefixime, gentamicin, metronidazole, and tetracycline were counted as below. The average number of bacteria in treated and untreated soils was estimated separately at zero, 1, 3, and 7 days for short-term heating (7 days), and the percentage of stable bacteria was statistically analyzed.This research was conducted as four separate tests of treated soil and treated soil with three antibiotics amoxicillin, cefixime, and metronidazole. Each experiment is in a factorial form with three factors: three types of soil (uncontaminated agricultural, mine-contaminated, and pasture near the mine), two antibiotic concentrations of 100 and 200 mg per kg of dry soil, and five types of antibiotics used in nutrient agar culture in short-term heating (7 Fasting) was done with a randomized complete design in three replications. Sampling was done at four times (zero, 1, 3, and 7 days) and then their average was processed and analyzed for each soil. Excel 2010 software was used to process the data of each experiment and draw graphs, and SPSS 20 software was used for statistical tests. The normality of data distribution was checked by the Shapiro-Wilk test. After standardization with Z-score, the effect of each treatment and their interaction was evaluated by analysis of variance. The mean test of each of the mentioned characteristics in the used treatments was performed with Tukey's method at the base of five percent. Research FindingsAbundance and percentage of stable bacteria in treated soils: The variance analysis of the logarithm of the abundance of bacteria counted in the soils showed that the simple effect of soil type on the number of bacteria was significant (P<0.01). The test of the average logarithm of abundance of bacteria in soils is shown in Figure 1. As can be seen, agricultural soil has the highest logarithm of abundance, which is not significantly different from pasture soil; But in both soils, it was significantly more than mine soil. It should be remembered that the characteristics of these soils were very close to each other. But their heavy metal concentrations were very different. Iron in agricultural, pasture, and mine soil is 22,691, 20,708, and 73,110 mg/kg respectively, lead in them is 33/20, 67/79, and 9749/66 mg/kg respectively, zinc is 58/33, 89/16, and 3839/20 respectively. mg/kg, cadmium respectively 0.75, 1.54, and 37.53 mg/kg, copper respectively 16.45, 18.70 and 89.58 mg/kg, manganese respectively 387.50, 837.50 and 66/ 9816 mg/kg and magnesium was 6052.08, 11166.67 and 4697.32 mg/kg, respectively; Therefore, except for magnesium, the highest amount of metals was found in the soil sampled from the mine. The order of contamination of the soils was according to the type of mine soil more or closer to the pasture soil and more than the agricultural soil. The high amount of heavy metals in the pasture soil can be related to the structure of the parent material of the soil, which is near the mine. However, the abundance of bacteria in it is not significantly different from agricultural soil.  Discussion of Results and ConclusionsAbundance and percentage of antimicrobial stability of microorganisms in test soils: Among the three test soils, mine soil had the lowest abundance of microorganisms. This could be related to more severe mine soil contamination or unsuitable soil habitat for bacterial growth.Indication of amoxicillin use in soil: In mine soil, the percentage of stable bacteria was lower; But the addition of amoxicillin, especially at a lower concentration (100 mg/kg soil), increased the percentage of stable bacteria in the soil, and nearly 100% of the bacteria in both agricultural and pasture soils by adding both concentrations of 100 and 200 amoxicillin compared to amoxicillin, cefixime, and metronidazole. They showed stability.Indication of the use of Cefixime in soil: By adding Cefixime (both 100 and 200 concentrations) to agricultural soil, the least stability of bacteria against tetracycline was seen. The stability of agricultural soil bacteria against the other four antibiotics added to the culture was not significantly different. Also, by increasing the concentration of cefixime in the soil to 200 mg, the resistance against four antibiotics, amoxicillin, cefixime, gentamicin, and metronidazole, reached nearly 100%. In the mine soil treated with cefixime (concentration of 100 mg/kg), the resistance against five antibiotics added to the culture was not significant. But by increasing the concentration of cefixime in the soil to 200 mg/kg, the stability of bacteria decreased, which was significant for three antibiotics in the culture (amoxicillin, cefixime, and metronidazole). In other words, increasing the concentration of cefixime in the soil decreased the stability of mine soil bacteria.Indication of metronidazole application in soil: In the agricultural soil treated with metronidazole, the lowest stability against tetracycline was seen, and by increasing the concentration of metronidazole from 100 to 200 mg/kg of soil, this stability against the antibiotics added to the culture decreased significantly. The bacteria of this soil had 100% stability against four antibiotics: amoxicillin, cefixime, gentamicin, and metronidazole at a concentration of 100 metronidazole. In contrast, mine soil bacteria treated with metronidazole at a concentration of 100 mg/kg were resistant to all five antibiotics; however, by increasing the concentration of metronidazole to 200 mg/kg, the response of bacteria to four antibiotics, amoxicillin, cefixime, gentamicin, and metronidazole was still stable; but they had a significant decrease against tetracycline. In pasture soil treated with metronidazole (both 100 and 200 concentrations), the lowest stability against tetracycline was seen.In this study, the percentage of stable bacteria in agricultural soil against amoxicillin and metronidazole was higher than in mine soil; but it never reached their size in pasture soil, and in line with previous studies, the percentage of stable bacteria in soils contaminated with metals, especially in pasture soil, was higher than in agricultural soil.Adding amoxicillin, cefixime, and metronidazole antibiotics to each of the soils, especially at a concentration of 100 mg/kg, caused a significant increase in the percentage of resistant bacteria against the five antibiotics used in the farm. This stability was significantly reduced especially in cefixime and metronidazole treatments by increasing the concentration of antibiotics to 200 mg/kg of soil, and mine soil bacteria had a more specific response in cefixime soil treatment. Pasture soil bacteria, like the treated soil, in both concentrations of the three soil treatments of amoxicillin, cefixime, and metronidazole, except for tetracycline, had high stability against the antibiotics added to the culture.In general, the pattern of stability of soil bacteria against antibiotics was Amoxicillin > Cefixime > Metronidazole > Gentamicin, and 100% stability of bacteria was not seen against tetracycline; Therefore, among the five antibiotics added to the slaughterhouse, tetracycline was the most lethal, followed by gentamicin. Only mine soil bacteria treated with 100 mg/kg metronidazole had significant resistance to tetracycline.Therefore, the response of bacteria to the antibiotics added to the soil and their stability in the studied soils are not the same and depend on the characteristics of the antibiotic, the soil, and their bacteria. Therefore, the percentage of stable bacteria in pasture soil was high; However, the percentage of bacteria resistant to tetracycline in the mine soil was higher than in the other two soils, especially at zero and 100 concentrations of the used antibiotics.

This cross-sectional descriptive study was undertaken to know the rate of intestinal parasites infestations in our school children population. A sum of 1155 fecal samples were analyzed from an equal number of children whose age were between 6-11 years old. The percentage of infestations were: Giardia lamblia (14.11%), Hymenolepis nana (1.21%), Ascaris lumbricoides (0.08%) and Enterobius vermiculairs (0.08%). We found no differences with regard to sex, age, father and mother levels of education, family size, body mass index (BMI) and the erythrocyte sedimentation rate (ESR) between the stools positive and the stools negative cases. Nearly all cases of giardiasis (99.4%) were symptomatic. Eosinophilia was seen in (5.5%) of the infested children with giardiasis and in (0.5%) of the non-infested children, the difference was statistically non significant (p=0.056).All cases of giardiasis (n=163) were treated with metronidazole 15 mg/kg/day in 3 divided doses for 7 days. Metronidazol was effective in (92.2%) of the treated children.

Previous studies have clearly shown that 2 weeks standard triple (Metronidazole + Bismuth + Tetracycline) or ranitidine + triple therapy (RMBT) always resulted in eradication of <80% in Iranian HP infected DU Patients. This is probably due to Metronidazole resistant rate of >40% in our DU Patients. The aim of this study was to compare 2 weeks clarithromycin - based regimen (Clarithroiycin + Bismuth + Tdracycline + Omeprazole= DCBT) with 2 or 3 weeks RMBT therapy and to elucidate which strategies. prolongation of treatment. Duration or replacement of Metronidazole by Clarithromycin) ,are more efficacious in HP eradication in DU patients in Iran.221 Patients with endoscopically proven DU ami positive rapid urease test in biopsy specimens presenting consecutively over;, 6 months period, were randomly allocated to three groups and recleved following regimens: A Omeprazole 2X20 mg, Clarithromycin 2x20 mg. Bismuth subcitrate 2X240 mg and Tetracycline 2X500 mg daily for Two weeks (OCBT). B: Ranitidine 2X300 mg. Bismuth subcitrate 2X240 mg, Metronidazole 2X500 mg and Tetracycline 2X500 mg daily for two weeks (RMBT). C: the same regimen as B but for 3 weeks. Eradication of HP was assessed at least S weeks after the completion of therapy with C 14 - urea breath test (UBT). The patients underwent a second endoscopy only if they had a positive UBT or were still symptomatic.221 patients were enrolled, and 205 patients had completed the 8 weeks follow-up (67 in A, 6S in Band 70 in C). Demographic data and endoscopic findings were comparable in all groups. Compliance was good with only one dropout in group B and one in C. Significant side effects were reported by 6.4%, of patients in A 17.7% in Band 14.2% in C; all of them were tolerable. Per protocol eradication rates of H. Pylori were as following: A (88.1%) higher than B (73.5 %) and C (71.4%) (A Versus B or C P<0.0). Eradication rates by intention to treat were as following: A (79.7%). B (67.65%) and C (68.5%).Prolongation of Ranitidinc + triple therapy from 2 to 3 weeks does not result in higher eradication rate of H.Pylori. Replacement of Metronidazole by Clarithromycin in OCBT regimen is clearly better than 2 or 3 weeks quadruple therapy, The 2 week OCBT therapy with 88.1% eradication rate by per protocol analysis in Iranian DU patients is still not the optimal and effective regimen required for HP eradication in other countries

For comparing the role of single dose of Metronidazole versus ceftizoxim as a standard, in prophylaxis of infection in the abdominal hysterectomy, a randomized clinical trial was done on 68 cases of elective abdominal hysterectomy in Mirsa Kochak Chan Hospital. After informed patients about study, they randomized undergoing received intra vaginal Metronidazole suppositories (1 gram) (34 cases) or intravenous ceftizoxim before surgery (34 cases). 4 cases of Metronidazole group and one of ceftizoxime exit the study because of some sterility problem during operation.There weren't any statistically significant differences between two group about age, weight, parity, during of hospitalization and Hemoglobine before operation, the kind of Incision, remove the Adenexa, duration of operation and the amount of bleeding in operation time. The method of repair of cuff was different between two group (p < 0.005). The complications after abdominal hysterctomy such as febrile morbidlity, urinary tract infection and wound infection weren't statistically significant different.It has been showed that metronidazole as a single dose prophylaxis in abdominal hysterectomy, is similar to ceftizoxim as standard prophylaxis.

Bacteria and their products play a major role in initiation and perpetuation of pulpo-periapical pathosis, and therefore the most important phase of endodontic treatment is the elimination or reduction of bacteria from root canal system.The purpose of this study was to compare the antimicrobial effects of two intracanal agents, an antibiotic combination and calcium hydroxide on infected dentinal tubules.Dentinal tubules of 60 root canal specimens of human teeth were infected with Enterococcus faecalis (RITCC 1918) for 3 weeks, and then exposed to a calcium hydroxide / saline paste or a mixure of ciprofloxacin, Metronidazole and tetracycline (25 microgram/ml of each drug) for periods of 24h, 48h, 7days.The bacteriological samples were taken by shaving the inner dentine from root canal with dental bur. Powder samples were incubated and the quantity of bacteria present assessed using spectrophotometry. Furthermore, the target organisms were cultured on blood agar plates and total numbers of colony forming units/m1 (CPU/m1) were counted.Results indicated that the drug combination effectively kills bacteria in the tubules after a 24h period of exposure, in contrast calcium hydroxide was in effective against E.faecalis even after 1 week of exposure.

OBJECTIVE: Helicobacter pylori eradication is recommended in gastric and duodental ulcer and MALT lymphoma management. For following up of patients after treatment of h.pylori infection, invasive and non-invasive procedures can be performed. The objective of this study was to compare invasive and non-invasive procedures. METHODS: 150 patients with h.pylori positive were selected for our study and divided into three groups. In all groups quadriple therapy (omeprazole, bismuth, metronidazole and amoxicillin) was done. One month later endoscopy and biopsy, serology (H.pylori ELISA IgA) and serology (H.pylori ELISA IgG) were done in first, second and third group respectively and compared for h.pylori eradication. FINDINGS: 127 patients remained as subjects in our study. In first group, endoscopy and biopsy was done again and we found no h.pylori in 70.7% of the cases of the first group, 35.7% and 20.5% of the cases of the second and third group respectively and this difference was statistically meaningful (p<0.001). CONCLUSION: In spite of the fact that endoscopy and biopsy in comparison to serology is an invasive procedure, it is recommended for short term follow up of patients (one month).