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Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran.

Background: Toxoplasmosis is a worldwide endemic disease. In congenitally infected infants and AIDS patients, toxoplasmosis causes high rates of morbidity and mortality. In these cases antibody detection is difficult; so detection of parasite or its components could be useful tool for early detection and following treatment of the infection.Methods: Sixty-three BALB/c mice were injected intra-peritoneal with 5×103 tachyzoites of Toxoplasma gondii RH strain, nine mice were sacrificed daily for 7 days. Fourteen mice were in­jected with phosphate buffer saline as control group. Dot-ELISA was performed for detection of T.gondii antigen in mice sera and capture - ELISA was done as golden standard assay too.Results : Toxoplasma gondii antigen was detected from day 2 in mice sera ; 22% of mice sera on day 2, 33% on day 3,77% on day 4 and 100% on day 5 till their death on day 7 had shown antigene­mia by dot - ELISA, no positive result was detected in control mice by dot- ELISA.Conclusion: Dot-ELISA is a sensitive method for diagnosis of T. gondii infection in the animal model; also, this technique is more rapid and easy to perform method in comparison with cap­ture-ELISA.

BACKGROUND AND OBJECTIVE: Due to the relationship between small bowel parasites and dyspepsia, investigation on the prevalence of such parasites among dyspeptic patients seems to be important. The aim of this study was to investigate the prevalence of small bowel parasites within a group of dyspeptic patients who have been referred to endoscopy ward of selected hospitals in Tehran, Iran. METHODS: This analytical study was performed on 130 patients who had undergone upper gastrointestinal endoscopy in endoscopy ward of Baghiatollah, Valiasr and Imam Khomeini hospitals of Tehran during 2004-2006. Duodenal aspiration, duodenal biopsy, and stool exam (S/E) were hired to find any infection with such parasites. Moreover, rapid urease test was used in order to find infection with Helicobacter pylori. These patients had no history of malignancy, genetic and/or metabolic diseases, and any history of treatment with antibiotics at least for 3 consecutive days within past month. FINDINGS: Stool exam was obtained from 105 patients, however all 130 patients had undergone duodenal aspiration and duodenal biopsy giardia was isolated from 4 patients (3.9%). Duodenal aspiration and biopsy were positive for giardia among 2(1.5%) and 1(0.8%) patients respectively. No infection with cryptosporidium, isospora, and cyclospora was detected. According to rapid urease test 61 patients (46.9%) were infected with Helicobacter pylori. Those with giardiasis were simultaneously infected with helicobacter pylori. CONCLUSION: It seems that giardiasis and infection with other small bowel parasites are not so important among dyspeptic patients, while Helicobacter pylori play an important role among such patients. In addition, larger number of stool exam infected with giardia can be diagnosed with formalin ether concentration method.

Background: Strongyloides stercoralis, the etiological agent of strongyloidiasis, is one of the most common parasitic nema­tode with the unique ability to complete its life cycle and proliferate within the host. Although it is an endemic parasite in Iran, no molecular characterization is available on isolates originated from the country. Therefore, this study was con­ducted for molecular identification of human Strongyloides isolates in the three most prevalent provinces."nMethods: After microscopical examination and agar plate culture of nearly 1500 stool samples, 20 isolates of S. stercoralis filari­form larvae were recovered from (Gilan and Mazandaran in north and Khouzestan in south) of Iran. The genomic DNA was extracted from all these samples and two primer sets were selected for amplification. ITS1 region of the rDNA gene was amplified by a nested Polymerase Chain Reaction (nested-PCR). The PCR prod­ucts were sequenced and analyzed in compari­son with the sequences deposited in GenBank."nResults: DNA sequence analysis of ITS1 region showed that all the 20 isolates were S. stercoralis. There was slight varia­tion in the ITS1 region among the isolates. "nConclusion: ITS1 sequencing seems to be a valid target for molecular identification of S. stercoralis.

Background: The aim of this study was to verify the occurrence of intestinal parasitic infections in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients in Iran in comparison with non-HIV individuals. Methods: A total of HIV+/AIDS patients (Group I) and 1220 clinically healthy individuals (Group II) were submitted to coproparasitological examination from 2003 to 2005. Results: The overall prevalence of intestinal parasites in group I and group II was 11.4% and 11.6%, respectively, without significant difference between two groups. The prevalence of infection for each helminth and pathogenic protozoan, in every group, was as follows: Group I: Blastocystis hominis (6.1%); Giardia lamblia (4.2%); Cryptosporidium spp. (0.9%); Isospora belli (0.26%); Strongyloides stercoralis (0.26%); Hymenolepis nana (0.13%); and Rhabditis axei (0.13%). Group II: Blastocystis hominis (6.5%); Giardia lamblia (4.1%); Strongyloides stercoralis (0.33%); Hymenolepis nana (0.16%); and Trichostrongylus sp. (0.16%). Although the prevalence of infection for extracellular parasites was not statistically different between two groups, however, the infection rates for enteric coccidians including Cryptosporidium spp. and I. belli were significantly higher in patients at AIDS stage than Group II. Conclusion: The results emphasize the needs for especial consideration of enteropathogenic intracellular coccidians in immunocompromised patients.

Cryptosporidium is an apicomplexan parasite of humans and a wild range of domestic as well as wild animals. An 833-bp fragment of the 18S-rRNA gene was used to identify Cryptosporidium spp. recovered from children and adult patients, in human immunodeficiency virus (HIV) positive and negative patients in Iran. Initial identification of cryptosporidiosis was carried out by Ziehl-Neelsen acid-fast staining method of stool samples. The samples, then, were identified specifically by nested PCR, targeting the most polymorphic region of the 18S-rRNA gene. The genotype encountered was detected by restriction endonuclease digestion of the nested-PCR product. Among 17 analyzed isolates, two different genotypes of Cryptosporidium were identified; 24% of the isolates belonged to C. parvum human genotype, and 76% to the potentially zoonotic species of C. parvum bovine genotype. The results of the present study showed that in contrast to HIV negative individuals, HIV positive individuals were more likely to be infected with zoonotic genotypes of the parasite; it was also confirmed the fact that zoonotic transmission of the parasite in Iran was as frequent as the transmission of anthroponotic origin. These outcomes are helpful for researchers to establish the corresponding prevention and treatment measures.

Toxoplasmosis is a wide distributed opportunistic infection caused by Toxoplasma gondii. This was a cross-sectional study of T. gondii antibody titer, which was conducted from June 2003 to August 2004 on renal transplant recipients in Iran. A total of 551 serum samples were obtained from randomly selected population referred from different areas all over the country to Shafa Central Clinic in Tehran. Patient’s information was recorded in a questionnaire before sampling. Two samples of finger-prick blood were collected from each person and antibody titer against Toxoplasma was assessed by Indirect Fluorescence Antibody (IFA) technique on serum samples. Totally 39 cases (7.1%) of samples were positive for antibody by the titer of 1: 20 and higher. On investigation of risk factors, no significant difference was found between consumption of under-cooked meat, close contact with animals, and the source of drinking water and seropositivity rate of toxoplasmosis. The relatively low seroprevalence rate of Toxoplasma infection shows the successful approaches to awareness of transplant recipients about the potential risks of acquisition of infectious diseases due to regular administration of suppressive drugs. However, the regular surveillance through serological screening of Toxoplasma antibody in kidney transplant recipients is advisable.

Amebiasis caused by Entamoeba histolytica is still mentioned as one of the major health problems in tropical and subtropical areas. E. histolytica has recently been redescribed as two distinct species; E. histolytica and E. dispar. In the present study, we characterized the 70 kDa Heat Shock Protein (HSP70) of E. dispar at molecular level and compared it with that of E. histolytica. With these findings, we were able to distinguishe E. dispar from the infectious E. histolytica. Pairs of 21 nucleotide primers were designed from highly conserved regions of the same gene in other eukaryotic cells. Mentioned primers were utilized in PCR by using isolated genomic DNA template of E. dispar and the PCR fragments were then sequenced. By the time, 1020 nucleotides have been sequenced and characterized within open reading frame of this new gene which encode a polypeptide with 337 amino acids. Nucleotide sequence comparison in gene data banks (NCBI, NIH) for both the partial DNA and its deduced amino acid sequence revealed significant homology with members of the eukaryotic 70 kDa HSP family. Small parts of the mentioned sequences from E. dispar were about 100% identical to the sequences of 70 kDa HSP from E. histolytica other eukaryotic cells. The new partial gene fragment and its encoded protein have been submitted to the gene data banks (NCBI, NIH) and registered under the accession number of AY763790.

Entamoeba histolytica is the etiological agent of invasive amoebiasis, the third leading parasitic cause of mortality in the world. Our aim was to find a molecular correlation between a glucosephosphate isomerase zymodeme analyses in E. histolytica zymodemes. It was demonstrated that natural and recombinant glucosephosphate isomerase enzymes of E. histolytica comigrated in the starch gel electrophoresis, indicating that the isoenzyme pattern of E. histolytica glucosephosphate isomerase could be explained from the primary sequences alone and means that expression of the polypeptides of the described sequences in Escherichia coli are able to reproduce the classical glucosephosphate isomerase isoenzyme patterns.

The determination of Toxoplasma gondii prevalence in a variety of domestic birds is thought as a good indicator of distribution of T.gondii ooccyts in the environment. To verify the potential role of domestic birds in circulating toxoplasmosis in Iran, the present study was conducted in Mazandaran Provinces, northern Iran. Latex agglutination test (LA) antibodies were found in 25 of 58 free-ranging chickens (Gallus domesticus) and ducks (Anas sp.). Also, viable T. gondii was isolated from 7 of 25 seropositive chickens and ducks by bioassay of their brains and hearts into mice. Most of the isolated strains were avirulant to mice. Genotyping of T.gondii isolates using Multiplex PCR for 5 microsatellite markers indicated that 7 isolates were type III. In this study type II and III isolates and mixed genotypes were not found. This study showed that domestic birds could have a potential role in transmitting toxoplasmosis to humans in Iran.

Acanthamoeba keratitis is a vision-threatening infection caused by pathogenic species of the genus Acanthamoeba. In this study, 13 Acanthamoeba keratitis cases were diagnosed among 52 keratitis patients. To confirm the identity of Acanthamoeba at the genus level, a PCR-based method was used, and their pathogenic potential was determined using in vitro cytotoxicity assays on human corneal epithelial cells. Twelve (92.3%) of Acanthamoeba keratitis patients were contact lens wearers; among them eleven (91.7%) wore soft contact lenses. 11/13 (84.6%) isolates were axenised in liquid culture medium, of which 10 (90.9%) isolates disrupted corneal cells. Nine (69.2%) isolates showed Acanthamoeba sp. group II, and four (30.8%) showed group III morphology. To our knowledge this is the first report of determination of Acanthamoeba pathogenicity in Iran. This study confirms the importance of determination of pathogenic potential of Acanthamoeba isolates for clinical purposes.

Enterobiasis is undoubtedly one of the most common human helminths infections through the world, with an estimate of 1000 million cases worldwide. Although adult worms and their eggs are frequently found in inflamed appendices, but the role of the parasite in producing appendicitis in humans still remains controversial. Although acute appendicitis may occur at any age, but it is relatively rare at the extremes of age. A histopathological study of infested appendices with Enterobius vermicularis was performed in Khuzestan province, south western Iran, during 2001 to 2003. All 40 samples had surgically been removed during the emergency operations and histopathological process with (H&E) staining has been performed for each. One of the main objects of this work was to collect more data about the possible role of this highly prevalent human round worm as a causative agent of appendicitis in humans, leading to different types of appendicitis in this part of the country. In this occasion over the slide examinations of the tissue sections, fewer cases than expected, with worm infested appendices were seen exclusively affected with this parasite.

Amoebiasis is one of the most important human diseases in many countries especially in tropical and sub-tropical regions. This study was carried out from August 1999 to February 2002 in order to determine the ratio of Entamoeba histolytica / Entamoeba dispar in some regions of Iran. A total of 16,592 stool samples were randomly collected from different agegroups in central, northern and southern Iran both from urban and rural areas. The samples were examined by direct and formalin-ether concentration methods. Two hundred and twenty six samples (1.36%) were positive for E. histolytica/E. dispar cyst (C.I = 1.18-1.54%). The prevalence of infection with E. histolytica/E. dispar was 0.78%, 3.9% and 4.6% for central, northern and southern part of Iran, respectively. The minimum rate of prevalence was 0.6% in Tehran, Yazd and Ardekan (central Iran), while the highest rate (8.3%) was seen in rural areas of Ahwaz (southern Iran).The study showed that ratio of E. histolytica /E. dispar was higher in southern regions (tropical and subtropical) than other regions. It seems that more sanitary facilities and health trainings are needed in different parts of the country, especially in southern Iran, where the rate of infection is high.

Giardia is one of the most common human parasites and causes a lengthly course of nonbacterial diarrhea. Disease outbreaks due to Giardia infection are often attributed to contaminated water supplies. A major problem associated with detection for this organism is the lack of sensitive and reliable methods. PCR has the potential to address many of the limitations.We have performed a PCR-based method for sensitive detection of Giardia cysts. Because the sensitivity of PCR is a function of the efficiency of DNA extraction from cysts, we have also compared some different methods for DNA extraction from the cysts. Giardia cysts were collected from infected human, partially purified and serially diluted samples were prepared. DNA was extracted by 3 different methods and we found that simple repeated freezing and thawing was the best method for extraction of DNA from the cysts. A 163 bp conserved fragment related to the giardial heat shock protein (HSP70) gene was used as the target for PCR amplification. We were able to detect as few as 5 cysts in the samples. The results suggest the potential utilities of PCR for sensitive detection of Giardia in water sources.

In 1926 for the first time Dobell and laid low synthesized and used Hsre+ s ( horse serum, ringer, egg+ starch rice) as a culture medium for growth of E.histolytica. since then this medium along with tens of other media have been used for growth of E.histolytica and other intestinal microorganisms. This medium has been used worldwide in many diagnostic and research laboratories. In Iran, in the past two decades they have used this medium in the school of public health and Institute of public health research. Rezaeian and (1989) simplified the original formula by not using the albumin of the egg and they found the same efficiency for the cultivation of Amoeba in HSr+ s medium. Since Oct.1996 , we have used HSr+ s medium for cultivation and diagnosis of Entamoeba histolytica. Eighty five percent of stool culture with Entamoeba ( cyst or trophozoite) have been positive, furthermore E. histolytica were cultured in the medium, with the average growth rate of 100000/ ml which indicates an efficient growth rate.

Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran.

Background: Toxoplasmosis is a worldwide endemic disease. In congenitally infected infants and AIDS patients, toxoplasmosis causes high rates of morbidity and mortality. In these cases antibody detection is difficult; so detection of parasite or its components could be useful tool for early detection and following treatment of the infection. Methods: Sixty-three BALB/c mice were injected intra-peritoneal with 5×103 tachyzoites of Toxoplasma gondii RH strain, nine mice were sacrificed daily for 7 days. Fourteen mice were in­jected with phosphate buffer saline as control group. Dot-ELISA was performed for detection of T.gondii antigen in mice sera and capture - ELISA was done as golden standard assay too. Results : Toxoplasma gondii antigen was detected from day 2 in mice sera ; 22% of mice sera on day 2, 33% on day 3,77% on day 4 and 100% on day 5 till their death on day 7 had shown antigene­mia by dot - ELISA, no positive result was detected in control mice by dot- ELISA. Conclusion: Dot-ELISA is a sensitive method for diagnosis of T. gondii infection in the animal model; also, this technique is more rapid and easy to perform method in comparison with cap­ture-ELISA.

Background: The aim of this study was to verify the occurrence of intestinal parasitic infections in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients in Iran in comparison with non-HIV individuals. Methods: A total of HIV+/AIDS patients (Group I) and 1220 clinically healthy individuals (Group II) were submitted to coproparasitological examination from 2003 to 2005. Results: The overall prevalence of intestinal parasites in group I and group II was 11.4% and 11.6%, respectively, without significant difference between two groups. The prevalence of infection for each helminth and pathogenic protozoan, in every group, was as follows: Group I: Blastocystis hominis (6.1%); Giardia lamblia (4.2%); Cryptosporidium spp. (0.9%); Isospora belli (0.26%); Strongyloides stercoralis (0.26%); Hymenolepis nana (0.13%); and Rhabditis axei (0.13%). Group II: Blastocystis hominis (6.5%); Giardia lamblia (4.1%); Strongyloides stercoralis (0.33%); Hymenolepis nana (0.16%); and Trichostrongylus sp. (0.16%). Although the prevalence of infection for extracellular parasites was not statistically different between two groups, however, the infection rates for enteric coccidians including Cryptosporidium spp. and I. belli were significantly higher in patients at AIDS stage than Group II. Conclusion: The results emphasize the needs for especial consideration of enteropathogenic intracellular coccidians in immunocompromised patients.

Toxoplasmosis is a wide distributed opportunistic infection caused by Toxoplasma gondii. This was a cross-sectional study of T. gondii antibody titer, which was conducted from June 2003 to August 2004 on renal transplant recipients in Iran. A total of 551 serum samples were obtained from randomly selected population referred from different areas all over the country to Shafa Central Clinic in Tehran. Patient’s information was recorded in a questionnaire before sampling. Two samples of finger-prick blood were collected from each person and antibody titer against Toxoplasma was assessed by Indirect Fluorescence Antibody (IFA) technique on serum samples. Totally 39 cases (7.1%) of samples were positive for antibody by the titer of 1: 20 and higher. On investigation of risk factors, no significant difference was found between consumption of under-cooked meat, close contact with animals, and the source of drinking water and seropositivity rate of toxoplasmosis. The relatively low seroprevalence rate of Toxoplasma infection shows the successful approaches to awareness of transplant recipients about the potential risks of acquisition of infectious diseases due to regular administration of suppressive drugs. However, the regular surveillance through serological screening of Toxoplasma antibody in kidney transplant recipients is advisable.

The COVID-19 pandemic has had an enormous impact on the healthcare systems. Along with its common complications, novel complications such as Rectus Sheath Hematoma (RSH) have been reported. We present 2 cases of RSH. (A) A 63-year-old woman with a known case of COVID-19 with severe cough presented sudden tachycardia and hypogastric pain; on physical examination, a huge lower abdominal tender mass was noticed. All the differential diagnoses were ruled out. (B) A 57-year-old woman with COVID-19 started complaining of tachycardia, pain, and a mass in the lower abdomen. On the physical examination, a lower abdominal tender mass was noticed. Both of the patients underwent an abdomen CT scan which confirmed a huge RSH. Conservative treatment and cessation of anticoagulant medications were continued. Both of them recovered and no evidence of further expansion was seen after 4 weeks of follow-up., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

The Coronavirus 2019 (COVID-19) pandemic placed significant pressure on healthcare systems across the globe, with many clinicians redeployed in unfamiliar specialties or disciplines. In England, a just-in-time interprofessional training and education programme was rapidly established to upskill nearly 2,500 people who volunteered to work at the NHS Nightingale London Hospital. Of the 488 respondents in our evaluation, representing a 20% response rate, most felt confident and safe to start work in NHS Nightingale London. Key findings were: streaming of learners should be driven by predicted shared roles in the workplace and previous experience; in situ training to experience how teams work together in the real clinical setting was well received; and online learning should be focused on essential learning. A just-in-time interprofessional training programme can be effective in upskilling and redeploying healthcare staff in emergency situations, and can be useful for supporting staff redeployment or upskilling across the NHS more widely., Competing Interests: The research team (GE, MP, MR and SN) were all independent of the NHS Nightingale London faculty. Two of the researchers (SN and GE) had attended several days at the O2 arena and ExCeL to observe the training and participate in some of the hospital/faculty liaison groups and faculty feedback huddles. LT was a member of the core team for the programme and advised on the design of the survey and provided context, but was not involved in the analysis of the survey data. JC was lead of the Education and Training work stream at NHS Nightingale London, but was not involved in the analysis or interpretation of survey data., (© Royal College of Physicians 2023. All rights reserved.)

Backgrounds: N-acetylcysteine (NAC) has broadly been used as an anti-oxidant agent in various types of diseases. This study aimed to assess the effect of NAC on the systemic lupus erythematosus (SLE) disease activity and outcome., Methods: In this randomized, double-blind clinical trial study, 80 SLE patients were recruited that were classified into two groups: 40 patients received NAC (1800 mg/day; 3 times per day with 8-h intervals) for 3 months and 40 patients as the control group received normal therapies. Laboratory measurements and disease activity based on the British Isles Lupus Assessment Group (BILAG) and SLE Disease Activity Index (SLEDAI) were determined before the initiation of treatment and after the study time period., Results: A statistically significant decrease in BILAG (P= 0.023) and SLEDAI (P= 0.034) scores after receiving NAC for a 3-month period was observed. BILAG (P= 0.021) and SLEDAI (P= 0.030) scores were significantly lower in NAC-receiving patients compared to the control group after 3 months. The disease activity in each organ based on BILAG score after treatment indicated a significant decrease in the NAC group compared to the baseline level in general (P=0.018), mucocutaneous (P=0.003), neurological (P=0.015), musculoskeletal (P=0.048), cardiorespiratory (P=0.047), renal (P=0.025), and vascular (P=0.048) complications. Analysis indicated a significant increase in CH50 level in the NAC group after treatment compared to the baseline level (P=0.049). No adverse event was reported by the study subjects., Conclusions: It appears that the administration of 1800 mg/day NAC to SLE patients can decrease the SLE disease activity and its complications., (© 2023. The Author(s).)

Background: Acanthamoebae are a causative agent of Acanthamoeba keratitis (AK) in immunocompetent individuals. Since access to propamidine isethionate (Brolene®) as a first-line treatment has been limited in recent years, in the current study, we examined the effects of pentamidine isethionate against trophozoite and cyst forms of Acanthamoeba ., Methods: This experimental study was conducted in the Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran, during 2019-2020. Pentamidine isethionate at concentrations of 50, 100, 200, 400, 600, 800, and 1000 μM were tested against trophozoites and cyst stages of T4 genotype, at 24- and 48-hour incubation period, and the viability was determined by trypan blue staining. In addition, the cytotoxic effect of the drug was examined in Vero cells using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay., Results: The 50% inhibitory concentration (IC50) of pentamidine isethionate on trophozoite after 24 and 48h were 97.4 μM and 60.99 μM. These results on cyst after 24 and 48h were 470 μM and 175.5 μM, respectively. In MTT assay, the drug showed an inhibitory effect on Vero cell growth with IC50 values of 115.4 μM and 87.42 μM after 24h and 48h, respectively., Conclusion: Pentamidine isethionate exhibited an inhibitory effect on trophozoite and cyst. Given that the trophozoicidal activity of the drug is in the safe dose, it could be suggested as an alternative in patients with AK; however, further investigation is needed in an animal model to confirm the data., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2021 Behnia et al. Published by Tehran University of Medical Sciences.)

Background: One of the underlying mechanisms of Parkinson's disease is the aggregation of α-synuclein proteins, including amyloids and Lewy bodies in the brain. Aim: To study the inhibitory effect of doped carbon nanotubes (CNTs) on amyloid aggregation. Materials & methods: Molecular dynamics tools were utilized to simulate the influence of CNTs doped with phosphorus, nitrogen and bromine and nitrogen on the formation of α-synuclein amyloid. Results: The CNTs exhibited strong interactions with α-synuclein, with phosphorus-doped CNTs having the most substantial interactions. Conclusion: Doped-CNTs, especially phosphorus-doped carbon nanotube could effectively prevent α-synuclein amyloid formation, thus, it could be considered as a potential treatment for Parkinson's disease. However, further in vitro and clinical investigations are required.

Introduction: The study of abnormal aggregation of proteins in different tissues of the body has recently earned great attention from researchers in various fields of science. Concerning neurological diseases, for instance, the accumulation of amyloid fibrils can contribute to Parkinson's disease, a progressively severe neurodegenerative disorder. The most prominent features of this disease are the degeneration of neurons in the substantia nigra and accumulation of α-synuclein aggregates, especially in the brainstem, spinal cord, and cortical areas. Dopamine replacement therapies and other medications have reduced motor impairment and had positive consequences on patients' quality of life. However, if these medications are stopped, symptoms of the disease will recur even more severely. Therefore, the improvement of therapies targeting more basic mechanisms like prevention of amyloid formation seems to be critical. It has been shown that the interactions between monolayers like graphene and amyloids could prevent their fibrillation., Methods: For the first time, the impact of four types of last-generation graphene-based nanostructures on the prevention of α-synuclein amyloid fibrillation was investigated in this study by using molecular dynamics simulation tools., Results: Although all monolayers were shown to prevent amyloid fibrillation, nitrogen-doped graphene (N-Graphene) caused the most instability in the secondary structure of α-synuclein amyloids. Moreover, among the four monolayers, N-Graphene was shown to present the highest absolute value of interaction energy, the lowest contact level of amyloid particles, the highest number of hydrogen bonds between water and amyloid molecules, the highest instability caused in α-synuclein particles, and the most significant decrease in the compactness of α-synuclein protein., Discussion: Ultimately, it was concluded that N-Graphene could be the most effective monolayer to disrupt amyloid fibrillation, and consequently, prevent the progression of Parkinson's disease., Competing Interests: The authors report no conflicts of interest for this work., (© 2020 Alimohammadi et al.)

Sarcocystis is a genus of eucoccidian parasites, which globally infects humans and various animals. In addition to economic losses in livestock industries, the parasite is a zoonosis that infects humans through contaminated beef and pork with the parasite sarcocysts. Therefore, this study was carried out to assess Sarcocystis contamination in beef and industrial raw beef burger samples from butcheries and retail stores in Tehran, Iran. Overall, 180 samples of 90 beefs and 90 raw industrial beef burgers with at least 80% meat were randomly collected in Tehran, Iran. Samples were studied microscopically after peptic digestion. Furthermore, sample genomic DNAs were used in conventional polymerase chain reaction (PCR) to amplify approximately 900-bp fragments from 18S ribosomal DNA. Of 180 samples, 170 samples (94.4%) were microscopically and 161 samples (89.44%) were molecularly positive for Sarcocystis spp. Eucoccidial DNA fragments were detected in 161 samples (89.4%), including 78 (86.6%) beef and 83 (92.2%) beef burger samples. No significant differences were found between the beef and beef burger infestations by Sarcocystis bradyzoites using statistical analysis ( P > 0.05). Statistically significant differences were seen between the sample type and the intensity of parasites in samples ( P = 0.003). Furthermore, differences between the conventional PCR results (positive/negative) and the intensity of parasites in samples were statistically significant ( P < 0.001). The considerable prevalence of Sarcocystis spp. in beef and beef burger samples reflects high transmission of the parasite in meat producing cattle, which is important due to food hygiene. Although the most prevalent bovine species, S. cruzi , is not a zoonosis, it is highly recommended to follow guidelines on the parasite transmission prevention due to the existence of S. hominis as a zoonotic bovine species., (© 2020 Published by Elsevier Ltd.)

Background: The aim of the present study was to develop a simple, portable, and rapid assay for serodiagnosis of toxoplasmosis based on recombinant Toxoplasma gondii ( T. gondii ) SAG1 (rSAG1) and GRA7 (rGRA7) proteins., Methods: The rSAG1 and rGRA7 proteins were expressed in Escherichia coli ( E. coli ) and purified in a single step by immobilized metal ion affinity chromatography. The immunoreactivity of the recombinant antigens was tested in an in-house IgG and IgM Dot enzyme-linked immunosorbent assay (Dot-ELISA) for potential use in serodiagnosis of T. gondii infection., Results: Results from the comparison of in-house rSAG1-Dot-ELISA with ELISA for the detection of anti- Toxoplasma IgG and IgM include sensitivity of 83.7% and 81.2%, specificity of 90.2% and 89.3%, positive predictive values of 85.9% and 68.4%, and negative predictive values of 88.6% and 94.3%, respectively. Sensitivity of 66.2%, specificity of 81.2%, positive predictive values of 71.6%, and negative predictive values of 77.1% were concluded from in-house IgG rGRA7-Dot-ELISA. The sensitivity and specificity of IgM rGRA7-Dot-ELISA included 87.5% and 83.9%, respectively. Sensitivity and specificity of in-house Dot-ELISA for a combination of rSAG1 and rGRA7 included 87.5% and 91.1% for IgG and IgM, respectively. Sensitivity and specificity of a combination of rSAG1 and rGRA7 for the detection of IgM in suspected sera to acute toxoplasmosis were higher than those for the detection of IgG in sera with chronic infections (90.6% and 92% instead of 86.2% and 91.6%, respectively)., Conclusion: The highlighted parameters of combined recombinant proteins were more significant than those of single recombinant proteins in in-house Dot-ELISA. These data suggest that the in-house Dot-ELISA based on rSAG1 and rGRA7 combination is a promising diagnostic tool with a similar sensitivity to the native antigens of T. gondii , which can be used for the serodiagnosis of toxoplasmosis in fields as well as less equipped laboratories., Competing Interests: The authors declare no conflicts of interest in this work., (© 2019 Teimouri et al.)

Nanotechnology based drug delivery systems for cancer therapy have been the topic of interest for many researchers and scientists. In this research, we have studied the pH sensitive co-adsorption and release of doxorubicin (DOX) and paclitaxel (PAX) by carbon nanotube (CNT), fullerene, and graphene oxide (GO) in combination with N -isopropylacrylamide (PIN). This simulation study has been performed by use of molecular dynamics. Interaction energies, hydrogen bond, and gyration radius were investigated. Results reveal that, compared with fullerene and GO, CNT is a better carrier for the co-adsorption and co-release of DOX and PAX. It can adsorb the drugs in plasma pH and release it in vicinity of cancerous tissues which have acidic pH. Investigating the number of hydrogen bonds revealed that PIN created many hydrogen bonds with water resulting in high hydrophilicity of PIN, hence making it more stable in the bloodstream while preventing from its accumulation. It is also concluded from this study that CNT and PIN would make a suitable combination for the delivery of DOX and PAX, because PIN makes abundant hydrogen bonds and CNT makes stable interactions with these drugs.