In vitro Culture and Multilocus Genotyping of Giardia duodenalis Trophozoites Obtained from Human Fecal Samples in Southwest of Iran

INTRODUCTION

The enteric protozoa, Giardia duodenalis (G. duodenalis), consists of eight distinct assemblages (A-H) with identical morphological characteristics and a direct life cycle. Successful axenic cultivation of this parasite is an important preliminary step for biological, drug resistance and phylogenetic studies. Moreover, G. duodenalis exhibits great genetic and biotypic diversity.

AIM

The current study aimed to evaluate in vitro culture and multilocus genotyping of G. duodenalis trophozoites obtained from human fecal samples in southwest Iran.

METHODS

Thirty human fecal specimens containing G. duodenalis cysts were collected from Ahvaz city (southwest of Iran). The purification of cysts was carried out by the sucrose flotation technique. The cysts were inoculated in a modified TYI-S-33 medium and was daily monitored for the development and viability of trophozoites. After extracting DNA, gdh, bg and tpi genes were evaluated using molecular techniques (the semi-nested PCR for gdh gene and the nested PCR for tpi and bg genes). Eventually, the amplified fragments were sequenced and then, the phylogenetic tree was drawn.

RESULTS

Of 30, the trophozoites were encysted from five samples. All three genes were detected in two cases of five samples using molecular techniques. The multilocus phylogenetic analysis demonstrated that all the two samples belonged to assemblage A and sub-assemblage AІІ.

CONCLUSION

Our findings indicated the presence of different numbers of trophozoites with variable development and survival rates in modified TYI-S-33 medium. Furthermore, the multilocus genotyping showed that these trophozoites belonged to assemblage A and sub-assemblage AІІ.

The Effect of Hydroalcoholic Extract of Quercus brantii and Artemisia aucheri Boiss Against Trichomonas vaginalis In vitro

Objective

Trichomoniasis is the most common sexually transmitted protozoan infection worldwide. Metronidazole is widely considered as the drug of choice for treating of trichomoniasis but considering its potential side effects, we aimed to assess the therapeutic influences of hydro-alcoholic extracts of Quercus brantii and Artemisia aucheri Boiss as alternative medications against Trichomonas vaginalis (T. vaginalis).

Methods

The trophozoites were cultured in TYI-S-33 medium at a density of 5x105 trophozoites/mL. Subsequently, they were incubated with varying concentrations of the plant extracts (32, 64, 125, 250, 500, and 1,000 μg/mL) and metronidazole (16, 32, 64, 125, 250, and 500 μg/mL), as the positive control. The number of trophozoites in each well plate was quantified after 2, 4, 6, 24, 48, and 72 hours using trypan blue staining. Finally, the viability of the parasite was assessed by vital methylene blue staining.

Results

The hydro-alcoholic extracts of Q. brantii and A. aucheri Boiss at concentrations of 125, 250, 500, and 1,000 μg/mL demonstrated significant efficacy against the parasite. Our findings indicated that the minimum effective concentrations were 125 μg/mL and hydro-alcoholic extracts of Q. brantii and A. aucheri Boiss have the ability to effectively eliminate T. vaginalis after 48 and 72 hours of treatment.

Conclusion

The findings of the present study showed that hydro-alcoholic extract of Q. brantii and A. aucheri Boiss can induce death in T. vaginalis. However, further complementary in vivo studies are needed to assess the components of these plants in the treatment of T. vaginalis.

Prevalence of Intestinal Protozoan Infection in Patients with Ulcerative Colitis (UC) in Isfahan, Iran

Background:

Determination of the prevalence of intestinal protozoan infection is a fundamental step to set up an effective control program to improve the health status of society and to establish efficient strategies. Intestinal pathogen and even non-pathogen protozoa consider as major causes of disease in patients with gastrointestinal problems. The objective of this study is to determine the prevalence of intestinal protozoan infection in patients with ulcerative colitis (UC) in Isfahan, Iran.

Methods:

The descriptive cross-sectional study carried out from 2013 to 2018 in Isfahan, Iran. One thousand nine hundred and sixty-five samples of feces from patients with UC collected and each sample examined using direct wet mounting with normal saline and iodine and sedimentation tests such as formol-ethyl acetate concentration and trichrome-staining methods.

Results:

From 655 patients, 185 (28.2%) infected with Giardia lamblia followed by Blastocystis hominis (27.3%), Endolimax nana (14.4%), Entamoeba coli (11.5%), Iodamoba butschlii (4.7%), Entamoeba histolytica (1.4%), and Chilomastix mesnili (0.6%).

Conclusions:

This study revealed a high prevalence of infection with at least one or six non-pathogenic and pathogenic intestinal protozoa in UC patients in the Isfahan region. Intestinal protozoa are a challenging public health problem wherever health care is limited in the area. The emergence of UC in the world results in the need to study etiologic factors. In order to obtain further information about the etiology of disease, we investigated the prevalence of intestinal protozoan infection in patients with UC in Isfahan, Iran.

Cancer Risk Assessment for Workers Exposed to Pollution Source, a Petrochemical Company, Iran

Background:

Air pollution have led to severe problem of adverse health effect in the world. This study aimed to conduct the health risk assessment, cancer risk analysis, and non-cancer risk for exposure to volatile organic compounds (VOCs) and hydrogen sulfide (H ₂ S) in petrochemical industry.

Methods:

In this cross-sectional research, 123 samples were collected in the ambient air in Iran during winter 2016. For sampling and analysis of VOCs and H ₂ S, 3 methods (numbers 1500, 1501, and 6013) presented by the National Institute of Occupational Safety and Health (NIOSH) were used. For determination of risk assessment of chemical pollutants, semi-quantitative method presented by the Occupational Safety and Health Division, Singapore was used. Finally, for calculation of cancer risk analysis, Chronic Daily Intake (CDI) and calculation of non-cancer risk, Exposure Concentration (EC) were used.

Results:

Average concentration of benzene (2.12±0.95) in breathing zone of workers were higher than the Threshold Limit Values-Time Weighted Average (TLV-TWA) (P<0.05). Among chemical substance, benzene had very high rank of risk in petrochemical industry. Rank of risk for H ₂ S, toluene, and xylene present in the breathing zone of workers was low. The mean cancer risk for workers exposed to benzene was estimated 8.78×10^−3, in other words, 8.7 cancer per 1000 i.e. higher than the acceptable standard of 10⁻⁶. In our study, non-cancer risk for BTX was higher than the acceptable standard of 1.

Conclusion:

In particular, overall cancer and toxic risk can be associated with long term exposure to benzene.

A new effective antiplasmodial compound: Nanoformulated pyrimethamine

OBJECTIVES

The aim of this study was to evaluate the efficacy of pyrimethamine-loaded poloxamer 407 nanomicelles on Plasmodium berghei strain NICD in vivo.

METHODS

Pyrimethamine-loaded nanomicelles were prepared and their zeta potential, particle size and polydispersity index were measured. For antiplasmodial assessment, 54 mice were randomly divided into six groups. Four groups were infected intraperitoneally with P. berghei, whereas the two remaining groups did not receive the parasite (negative controls). Three of the P. berghei-infected groups received treatment with either pyrimethamine-loaded nanomicelles (2 mg/kg), pyrimethamine (2 mg/kg) or empty nanomicelles (2 mg/kg); the fourth group remained untreated (positive control). The parasitaemia rate, survival rate and histopathological changes in the liver, spleen and kidneys were examined and were compared with the negative and positive control groups.

RESULTS

The mean parasitaemia rate differed significantly between the nanoformulated pyrimethamine group and each of the other groups (P<0.05). Moreover, the survival rate of mice in the nanoformulated pyrimethamine group (7/9; 78%) was significantly higher compared with each of the other groups (P<0.01). The main histopathological changes, including hepatic necrosis in the liver, lymphoid hypoplasia in the spleen, and tubular nephrosis and perivascular and interstitial lymphocytic infiltration in the kidneys, were considerably lower in the nanoformulated pyrimethamine group than in the pyrimethamine and positive control groups.

CONCLUSION

Pyrimethamine-loaded nanomicelles showed potent antimalarial activity and can be considered as a potential candidate for further examination of their suitability as an antimalarial drug.

A wide diversity of zoonotic intestinal parasites in domestic and stray dogs in rural areas of Kermanshah province, Iran

Dogs can act as reservoirs, carriers, and transmitters of several zoonotic intestinal parasites that can cause serious health problems for humans. The aim of this study was to determine the prevalence of intestinal parasites in dogs in Kermanshah Province, west of Iran. Faecal samples were collected from domestic and stray dogs from 30 rural areas of Kermanshah province from August 2014 to April 2015 and were analyzed by formalin-ether sedimentation, sucrose otation technique and the modied Ziehl-Neelsen method. Out of 301 dogs examined, 230 (76.4%) were infected with at least one parasite. The incidence on the different types of intestinal parasitic species recovered from domestic and stray dogs are as follows: Toxocara leonina (20.8% and 27.6%), T. canis (7.5% and 9.4%), Taenia spp. (9.2% and 9.4%), hookworm spp. (18.3% and 33.7%), Capillaria spp. (0.8 and 1.7%), Dicrocoelium dendriticum (0.8% and 3.3%), Fasciola spp. (0.8% and 2.2%), Acanthocephal spp. (3.3% and 5.5%), Trichuris vulpis (0.8% and 1.7%), Dipylidium caninum (4.2% and 3.3%), Physaloptera spp. (6.7% and 6.6%), Cryptosporidium spp.(21.7% and 25.4%), Eimeria spp. (35.0% and 34.3%), Giardia spp. (6.7% and 12.7%), Cystoisospora spp. (7.5% and 5.5%), Blastocystis spp. (18.3% and 20.4%) and Sarcocystis spp. (6.7% and 7.2%), respectively. Signicant difference in infection rates was observed between domestic and stray dogs (P>0.05). Hookworm and Eimeria spp. were the most common intestinal helminth and protozoa detected with 83 (27.6%) out of 301 and 104 (34.6%), out of 301, respectively. There was no significant difference in prevalence and distribution of intestinal parasites between male and female dogs (P>0.05). The wide range of zoonotic parasites indicated that people residing in rural areas in Kermanshah province are at risk of exposure to these pathogens. In this respect, appropriate implementation of control programs by public health authorities and veterinarians should be taken into account.

Development of a Latex Agglutination Test as a Simple and Rapid Method for Diagnosis of Trichomonas vaginalis Infection

Trichomoniasis is a worldwide infection and due to its complications rapid and accurate diagnosis of infection especially in pregnant women is very important. In this study, development of a latex agglutination test using native antigens for rapid diagnosis of trichomoniasis is investigated. Trichomonas vaginalis was harvested from TYIS33 culture medium and anti Trichomonas vaginalis antiserum was raised in rabbits. Salt precipitation method was used for antibody purification. Polyesteren latex particles coated with purified antibody and used for detection of Trichomonas vaginalis. Clinical samples of vaginal discharge were collected from 500 women and examined for Trichomonas vaginalis by using wet mount, culture and latex agglutination tests. Sensitivity and specificity of latex test was determined considering culture as golden standard. Sensitivity and specificity of latex agglutination test was 100% and 81% and those of wet mount were 33.3% and 100%, respectively. Positive and negative predictive values of latex agglutination test were 6% and 100%, respectively. Due to inconvenient sensitivity and specificity of the latex agglutination test developed in this study, further work is recommended to improve the test.

Prevalence rate of Cryptosporidium infection in hemodialysis patients in Iran

Cryptosporidium is one of the most common causes of diarrhea in the world, which can be severe and prolonged in immunocompromised patients. We compared the prevalence rate of Cryptosporidium infection in hemodialysis patients and 2 control groups (i.e., their healthy family members and normal population). Stool specimens of 104 adult outpatient chronic hemodialysis patients, their 91 healthy family members, and 140 healthy individuals were examined for the presence of Cryptosporidium oocysts by using a modified acid-fast staining method. Twelve (11.5%) dialysis patients were infected with Cryptosporidium. This was significantly higher than 4 (4.4%), and 5 (3.6%) cases in the 2 control groups, respectively (p < 0.05). There was no significant difference between the 2 control groups. The prevalence rate of Cryptosporidium infection did not correlate with patients' sex, age, duration of dialysis, history of kidney transplantation, or history of taking immunosuppressive drugs. However, it was significantly higher in diabetics vs. nondiabetics (19.4% vs. 8.3%, respectively, p < 0.05). Our results indicate that the prevalence rate of Cryptosporidium infection is considerably higher in dialysis patients than in the general population. Moreover, dialyzed diabetic patients had the highest rate of infection. As hemodialysis patients are candidates for renal transplantation, general preventive measures against acquiring Cryptosporidium infection must be considered.