s.h. hekmati moghaddam

Introdction: Patulin is a dangerous toxin produced by various fungi. Hence, the current study aimed to evaluate adsorption of Patulin by nanocellulose conjugated with Poly-guanine in contaminated apple juice.
Firstly, nanocellulose was synthesized, and then it was bonded to poly-guanine by a cross-linker. Then, concentration serial of Patulin was prepared in the apple juice, conjugated nanoparticles were added to them, and all were incubated at 37 ºC. After incubation, the Patulin concentration was measured by HPLC, and finally the adsorption percentage was calculated for each tube. Regarding molecular simulation, the initial structures of Patulin and nanocellulose conjugated with Poly-guanine were inserted into Hyperchem software, and their intermolecular energy was calculated during 50 picoseconds.
The results of the present study demonstrated that there was a significant direct correlation between the initial concentration of Patulin and the adsorption percentage of toxin. In addition, the adsorption maximum was reported 70±5 %, and the intermolecular energy between two structures was -20.3 Kcal/mol based on the computational simulation.
It can be concluded that nanocellulose conjugated with Poly-guanine seems to be a good adsorbent for Patulin, which is demanded to be used in the future studies in regard with its application.

Aflatoxin leads to liver cancer, its removal in the foodstuff is very important. The aim of this study is to investigate the adsorption of aflatoxin B1 by nanocellulose conjugated with aptamer in acidic, alkali, and neutral conditions.
First, nanocellulose was synthesized by acid hydrolysis and then conjugated with aptamer by cross-linker. Then, serial concentrations of conjugated nanocellulose (0.6, 1.25, 2.5, 5, and 10 mg/mL) were separately mixed with aflatoxin solution (1000µg/mL), and incubated at 37 °C for 0.5 h at pH of 1, 7, and 13. Then, the percentage of aflatoxin adsorption was measured at 340 nm.
The decrease of pH led to increase of adsorption up to 40%. Statistically, there was significant difference between the quantity of adsorption at acidic condition and the quantity of adsorption at alkali and neutral conditions (P Aflatoxin could be adsorbed by conjugated nanocellulose, and this power of adsorption is increased at acidic condition.

Allicin is extracted from Garlic, and can attach to the tiol groups of proteins by tiosulfanate group. This attachment leads to damage of various proteins and enzymes of microbes, and can affect wide spectrum of viruses, bacteria, fungi, and parasites. The aim of this study was to investigate the stability, toxicity and antimicrobial effect of allicin solution. First, serial concentrations of allicin solution were prepared, and exposed to suspension of standard isolates of bacteria (Escherichia coli, Staphylococcus aureus, andPsodomonasaerogina) and fungi (Aspergillusnige rand Candida albicans).The minimum inhibitory concentration(MIC50 and MIC90) of this compound against each isolate was determined. To evaluate the toxicity of allicin solution, the suspension of skin cells of Balb/C mice was prepared, and incubated with serial concentrations of allicin for 6, 12 and 24 h. Then, cell viability was calculated by MTT assay, based on control. To evaluate stability of allicin solution,some pieces of sterilized marble were prepared, and their surfaces were treated with the solution of allicin. After 6, 12 and 24 h,marbles were sampled, inoculated on the nutrient agar, and incubated for 48 h at 37 °C. Finally, the number of colonies grown on each plate was counted. The micro-dilution test showed that allicin solution had antimicrobial effecton the all bacterial and fungal isolates which studied. This study also showed that the toxicity of allicin solution slightly dependent on the time and concentration, but increase the time until 24 h had nota significant impact on the reducing of stability. The allicin solution has antimicrobial activity and its toxicity is negligible. Also, this material has high stability in the environmental conditions.

Silica nanoparticles could enter the living animals and humans through inhalation، ingestion، injection and skin، exerting potentially adverse effects on health and environment. The aim of this experimental laboratory study was to evaluate toxicities of silica nanoparticles in the form of wire، rod and sphere with different sizes (20، 50 and 100 nm) on rat pulmonary cells after 6 and 24 hours of exposure، using from 3- (4،5-Dimethylthiazol-2-y1) -2،5diphenyltetrazolium bromide (MTT) and 3- (4،5-dimethylthiazol-2-yl) -5- (3-carboxymethoxyphenyl) -2- (4-sulfophenyl) -tetrazolium (MTS) cytotoxicity tests.

Two male Wistar rats were anesthetized، their blood was completely replaced with Crebs solution، and their lungs removed to be digested for preparation of single cell suspensions in medium culture. Cell suspensions were separately treated with the above-mentioned nanoparticles at concentration of 500 µg/mL and 37 ºC incubation، and cell viability was assessed after 6 and 24 hours.

This study showed that smaller (20 nm) nanoparticles had more cytotoxic properties than larger ones. Also، spherical nanoparticles induced more cytotoxicity compared with other forms. Longer (24 hours vs. 6 hours) exposure resulted in slightly more cell death.

Cytotoxicity of nanoparticles depends on their shape، size and exposure duration.

Direct observation of cell behavior is involved in vivo and ex vivo study. The aim of this study was to investigate the effect of magnesium oxide nanoparticles on isolated rat lung alveolar pneumocyte cells، after severance and determine the amount of no-effect nanoparticles. In this lab trial study، in addition to determine the viability of isolated cells with Trepan blue، the morphological changes of cells exposed to 1، 6 and 24 hours (hr) with magnesium oxide nanoparticle concentration of 0. 1، 1، 10، 100، 500 and 1000µg/ml were evaluated using light microscopy. Trepan blue staining (93%) showed that 93% of live alveolar pneumocytes were isolated. According to the results obtained after separation of cells treated with nanoparticle، with exception of fairly alteration in 1000µg/mL concentration، no any morphological changes in cytoplasm، nucleus and membrane was observed after 1 and 6 hr exposure. When time exposure increased to 24hr، the mild and severe alteration occurred in concentration of 100µg/ml and afterward. The (NOAEL) values for MgO nanoparticle after 6 and 24hr exposure، were determined 1000 and 100µg/ml، respectively. In this study it was shown that magnesium oxide nanoparticles in low concentrations and short exposure time has little effect on lung cells، but the increase in both concentration and duration of exposure to magnesium oxide nanoparticles was enhance morphological cell alteration.

Organophosphates use in agriculture and concern about their effects on human is increasing. This study was conducted to investigate the activity of blood cholinesterase in sprayers. In a descriptive and analytical cross-sectional study، 60 (30 sprayers and 30 control individuals) with age range of 29-62 years، mean age of 44. 33±8. 55 years were studied and the results were analyzed using SPSS version 11. The average and standard deviation of erythrocyte cholinesterase (AchE) and plasma cholinesterase (PchE) concentration was 5573. 2± 1229. 51 U/L and 144. 73±52. 3 IU/grHgb، respectively. Minimum and Maximum activity of erythrocyte cholinesterase was also 71. 07 and 291. 9 IU /gr، respectively. The average concentration of both erythrocyte cholinesterase (AchE) and plasma cholinesterase (PchE) in the case group was lower than the control group. A significant difference was observed between two groups (p<0. 05). In conclusion، high exposure to organophosphates was observed and it is needed to implement the occupational health program for prevention of health effects.

Major endemic foci of cutaneous leishmaniasis are present in different areas of Iran, including the city of Yazd, and it is one of the important parasitic diseases in tropical and subtropical regions. The first step in reduction of the disease cases is acknowledging its epidemiologic status. The present descriptive cross-sectional study was performed during 6 years, from autumn of 2000 to autumn of 2006 on the 1020 cases referred for diagnosis to the Yazd Central (reference) Medical Laboratory. The scraping method was used for preparation of direct smears, which were stained with Giemsa. From the 1020 cases suspected of cutaneous leishmaniasis (450 males and 570 females, comprising 44.1% and 55.9% of them, respectively), in 615 patients (60.3%) the amastigote form of parasites were found, of them 290 patients (47.2%) were males and 325 patients (52.8%) were females, showing no significant difference (P value=0.22). The most common location of the lesion was hand (In 148 patients or 24% of cases), followed by face, forearm, foot, arm, and trunk. In 394 patients (64%) there was a single ulcer, and 221 cases (36%) had more than one lesion, including a patient with 16 lesions. The most commonly affected age groups were 10-19 years (23.5%) and 20-29 years (21.5%). Also it was shown that the most common areas of residence in patients (in 155 cases, or 25.2%) was in the Imam Khomeini street (Hazira and Ghale Asadan areas) of Yazd city, where there are many ancient houses located on destroyed water channels and the resident people are in a low socioeconomic status. Considering the high (60.3%) positivity rate of leishmaniasis in referred cases from the physicians, it seems necessary to raise the clinical index of suspicion in cutaneous ulcers. It can also be suggested that health system officials pay more attention to detection of vectors and reservoirs of leishmania, in addition to educating the people at risk, for recognition of cutaneous leishmaniasis and its ways of control.

Diagnosis and treatment of parasitic infections are very important because of pathologic changes and clinical symptoms produced in the host, and for taking measures against them. These diseases have more adverse effects and more importance in children. This study was aimed at determining the prevalence of intestinal parasites and their clinical manifestations in children 0-14 years old referred to Yazd Central Laboratory. The present cross- sectional descriptive study was performed during the April 2005 to September 2006, with data obtained from the stool samples of 1500 children, using both wet mount smear (physiologic saline and Lugol΄s solutions) and formalin-ethyl acetate concentration method for detection of the intestinal parasites and also with the tape test for eggs of Enterobius vermicularis and Taenia. From 1500 examined stool samples, 128(8.5%) cases were positive for one of the intestinal parasites, including 67(52.3%) females and 61(47.7%) males. Ninety five percent of positive cases were infected with protozoa and 5% with helminths. The most frequent protozoans were Blastocystis hominis 41.3%, Giardia lamblia 33.6%, and Entamoeba coli 14.7%. Enterobius vermicularis (4.3%) and Hymenolepis nana (0.7%) were the helminth species. The most abundant infection rate was shown in the 5-9 years old group, with a significant difference compared with other age groups (P< 0.05). About 87% of children infested with Blastocystis hominis showed more than 5 Blastocystis per 400x microscope fields, and 100% of children infested with Giardia lamblia and Chilomastix mesnili had clinical symptoms. In this study, lower contamination rates in comparison with the similar studies conducted in other regions of the country was seen, which may be as a result of the hot and dry climate and improved personal hygiene and public health services. There is a need for further studies about the prevalence and clinical symptoms of some parasites such as Blastocystis hominis and Chilomastix mesnili.

Infection with Strongyloides stercoralis, an intestinal nematode of humans and some animals, is rare in dry climates such as Yazd. This article presents a patient with this infection who was mistakenly under treatment for ulcerative colitis, which recovered after proper diagnosis and anti-helminthic therapy. A 32 years-old man from Qeshm referred to Yazd Central Laboratory in August 2005, when many rhabditiform larvae of S. stercoralis were found in stool exam. Until then, he was under treatment with sulfasalazine and other drugs for ulcerative colitis. Treatment with tiabendazole was completely effective at relieving intestinal symptoms, without recurrence in 15 months of follow-up. All lab reports and documents are available. Careful attention is necessary because delayed diagnosis of S. stercoralis may lead to severe and fatal strongyloidiasis, and this parasite can manifest itself with symptoms similar to other intestinal diseases, such as ulcerative colitis.