فهرست مطالب

  • سال بیست و پنجم شماره 3 (پیاپی 112، پاییز 1399)
  • تاریخ انتشار: 1399/07/28
  • تعداد عناوین: 8
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  • Mohammadsadegh Nadimifar, Mohammad Rostami Nejad, Mehran Habibi-Rezaei, Mohammad Reza Zali, Ali Akbar Moosavi-Movahedi* Pages 171-178

    Coeliac disease, or celiac sprue, is an autoimmune disorder of the small intestine with a genetic background. As a result of immunological responses to gluten consumption, small bowel villi will have damaged and cause malabsorption of nutrients. The symptoms of this disorder appeared due to presence of Gluten, a stored protein in the endosperm of grains such as wheat, barley and rye in the patient’s diet. Gluten made up of two protein components called gliadin and glutinine. An alcohol-soluble component, gliadin, is the main cause of Coeliac disease symptoms. The "N" terminal of gliadin usually has repetitive sequence rich in glutamine, proline, phenylalanine, and tyrosine. Due to the mechanism of Coeliac disease, trans-glutaminease and glutamic acid in the N terminal of Gluten are played very important role. On the other hand, a human leukocyte antigen, HLA-DQ2, as an internal factor, plays a major role in the immunological response. In this study, in addition to introducing the mechanism of celiac disease, the molecular structure of gluten and it interacts with HLA-DQ2 will be reviewed.

    Keywords: Celiac Disease, Gluten, Gliadin, Glutamic Acid, Trans-Glutaminease, HLA-DQ2
  • Parastoo Saniee*, Marzieh Raoofimanesh, Farideh Siavoshi, Sara Kadkhodaee, Gelareh Poostizadeh Pages 179-187
    Background

    Helicobacter pylori (H. pylori) exhibits considerable genetic diversity, which contributes to adaptation to the new host, wide spread, and its ability to cause various gastrointestinal diseases. In this study, the possibility of the presence of H. pylori strains with different genetic and antibiotic resistance patterns in a single host was investigated.

    Material and Methods

    Gastric biopsy samples of 10 H. pylori-positive patients were cultured on selective brucella agar and incubated microaerobically. Four single colonies per patient were picked from the primary culture and sub-cultured to obtain pure H. pylori isolates. Antibiotic susceptibility/resistance of primary culture, as well as pure H. pylori, isolates to nine common antibiotics in eradication (in MIC) was assessed by agar dilution method. Genotyping was performed by amplification of cagA and signal (s1 and s2) and middle (m1 and m2) regions of vacA genes.

    Results

    Heteroresistance was observed in seven patients to tetracycline, in five patients to levofloxacin, in five patients to metronidazole, in three patients to ofloxacin, in five patients to rifampin, in two patients to furazolidone, in one patient to amoxicillin, and in one patient to clarithromycin. Considering the cagA gene and vacA s and vacA m alleles, four patients carried H. pylori isolates with two different genotypes and three patients carried the isolates with three different genotypes.

    Conclusions

    The presence of heterogeneous and heteroresistance H. pylori strains in a single host can have a direct impact on the treatment outcome of the infection. In this regard, in order to have accurate information on H. pylori infection in each individual, sampling of several gastric areas along with examining of 3-10 single colonies from the primary culture is recommended.

    Keywords: Helicobacter pylori, Antibiotic resistance, Genetic diversity
  • Hamed Zamanian, Ahmad Shalbaf* Pages 188-197
    Background

    One of the common diseases is fatty liver disease, which can be seen significantly in patients with excessive obesity as well as patients with diabetes. Using ultrasound imaging methods, it can be possible to identify and evaluate patients affected by this disease. The aim of this study was to use advanced machine learning algorithms for better and more accurate classification of the acquired images from different patients affected by fatty liver disease.

    Materials and Methods

    In this study, the acquired ultrasound images of 55 patients suspicious as having fatty liver disease have been used. The level of fat for different patients was labeled by biopsy sampling. Based on this experiment, the patients were predicated as having a fatty liver when more than 5% of their liver hepatocytes were accompanied by infiltration of fat. Then, we utilized some pre-trained convolutional neural networks, including Inception-ResNetV2, GoogleNet, and AlexNet to extract high-level features of the collection of the acquired images. After that, a SoftMax layer was implemented to classify the images that indicated fatty liver.

    Results

    The resulted precisions for Inception-ResNetV2, GoogleNet, and AlexNet pre-trained convolutional networks were 0.8108, 0.9459, and 0.9932, respectively. Also, the area under the curve of receiver operating characteristics (AUC) for these networks were 0.9757, 0.9960, and 0.9963, respectively.

    Conclusions

    The proposed intelligent algorithm can help sonography experts to recognize the liver tissues with fat automatically and accurately without the need for a specialist to assign the region of interest for evaluation.

    Keywords: Fatty liver, Ultrasound imaging, Machine learning, Deep transfer learning networks
  • Mohaddeseh Zojaji, Alireza Sharifi, Ahmad Hormati*, Faezeh Alemi, Mahboubeh Afifian, Seyed Hassan Abedi Pages 198-207
    Background

    Helicobacter pylori infection is one of the most common bacterial infections that is affecting approximately half of the world's population. This bacterial infection causes gastrointestinal diseases, including gastritis and peptic ulcers. It is also the only microbial agent with definite association with gastrointestinal cancers such as adenocarcinoma and gastric mucosal lymphoma. The prevalence of this infection in Iran is reported to be 36% to 90% in different regions. Therefore, eradication of this germ is of great importance and has always been of interest to clinical researchers.

    Objective

    The aim of this study was to evaluate the antibiotic resistance of Helicobacter pylori infection in different regions of Iran based on previous studies. Also, introducing the most effective antibiotics based on antibiotic susceptibility in Iran is the ultimate goal of this study.

    Material and Methods

    Many studies have been done in different regions of Iran to show the antibiotic resistance of Helicobacter pylori, but no comprehensive review of these studies has been done until 2019. It is worth noting that the prevalence of resistance to antimicrobial therapies is increasing. Therefore, we conducted a review of these studies to obtain comprehensive results on the antibiotic susceptibility of Helicobacter pylori. We searched the databases of Google Scholar, Scopus, and PubMed and reviewed the studies in Iran until 2019 with more emphasis on the last five years.

    Results

    A total of 48 articles were reviewed, the results are summarized in the tables, and the best antibiotics to affect on Helicobacter pylori infection were also identified. It is worth noting that eradication rates in different regions of Iran based on different treatment regimens of three, four, and concomitant drugs in different studies have also been shown in tables, separately.

    Conclusions

    According to available data, the best first-line eradication regimen in Iran appears to be a 14-day quadruple therapy with amoxicillin, clarithromycin, bismuth, and a proton pump inhibitor (PPI). Cases of treatment failure should also be treated with a combination of amoxicillin and levofloxacin, or amoxicillin and rifabutin in combination with a PPI after evaluation and determination of antibiotic resistance.

    Keywords: Helicobacter pylori, Gastritis, Antibiotic resistance, Eradication, Iran
  • Fatemeh Keyfi*, Veys Hashemnia, Farzaneh Hosseinzade, Hurie Tajik, Abdolreza Varasteh, Nurie Sharifi Pages 208-215
    Background

    Vitamin D is a fat-soluble metabolite, which can be mainly obtained from skin exposure to the sunlight. Foodstuffs containing vitamin D such as oily fish, eggs, and mushrooms are other sources for this vitamin. Vitamin D plays its role in the body via its intracellular receptor. The discovery of vitamin D receptors on a wide range of body tissues indicates the broad effects of this metabolite on the human body. The aim of this study was to investigate vitamin D mechanisms and measurement methods.

    Materials and Methods

    In this study, out of 72 primary articles searched in PubMed and Google Scholar databases from  2012 to 2017, 16 articles with the keywords vitamin D, gold-standard methods, pharmaceutical forms, and body organs were selected and studied.  

    Results

    Studies have shown the effects of vitamin D on almost all body organs, including skin, bone, liver, intestine, and muscles. Some hormonal functions are also correlated with vitamin D. Since vitamin D deficiency may interfere with numerous mechanisms in the body, taking vitamin D supplements would have significant effects on preventing many diseases.  

    Conclusions

     As vitamin D deficiency is quite common worldwide, it is recommended to measure vitamin D levels annually and to take vitamin D supplements under the supervision of a physician. The reference method used for vitamin D concentration assessment is liquid chromatography-tandem mass spectrometry. Other measurement techniques have also been used in order to quantify this metabolite, such as immunoassays and chemiluminescence assays.

    Keywords: Vitamin D, Gold standard methods, Pharmaceutical forms, Vitamin D mechanism of action
  • Enayatollah Noori, Habib Farahmand, Jafar Ahmadi, Afshin Tahmasebi, Sajad Rezvan*, Morteza Khademalhosseini Pages 216-221

    Liver abscess can be defined as an accumulation of secretions within the liver parenchyma, which may be caused by bacterial, fungal, or parasitic microorganisms. In this study, we reported a case of liver microabsorption in a 16-year-old girl with no history of underlying diseases, which could ultimately lead to the diagnosis of Crohn's disease in this patient. The patient was a 16-year-old girl presenting with nausea, vomiting, diarrhea, and anorexia. Of the accompanying symptoms, she mentioned two occasions of fever and chills. The patient was also hospitalized a week ago and in the tests performed, the number of white blood cells was 12,400 and the positive occult blood test in the fecal test was 8-10 red blood cells and 4-45 white blood cells. She was treated with a diagnosis of gastroenteritis and was discharged with partial recovery. There was nothing special in the examination. The only ultrasonography revealed the presence of free fluid in the loop near the ovaries. The patient-specific tests that were requested were all normal. Repeat ultrasonography of the patient reported normal liver with numerous hypovaccal nodules in the entire parenchymal artery, which had increased in size and number compared with the previous assessment. Finally, the patient was discharged 5 days after the fever stopped and due to the improvement of her general condition with the prescription of levofloxacin and metronidazole, and was referred to the clinic one week later In this case, we attempted to review the literature on the etiology, diagnosis, and treatment of hepatic abscess for a physician.

    Keywords: Micro-abscess, Liver, Underlying cause
  • Noushin Bazrafshan, Sahar Ravanshad, Mitra Ahadi, Ali Beheshti namdar* Pages 224-228
    Background

     Colorectal cancer is one of the most common cancers among men and women worldwide. Patients who are diagnosed at the early stages of the disease have a significantly better prognosis, lower mortality, and lower burden of the disease. Thus, screening methods, namely colonoscopy, and fecal occult blood test are effective means of a timely diagnosis. However, there are pearls and pitfalls among doctors in the decision to participate and implement these methods. This article aims to evaluate and discuss the attitude and behavior of physicians toward colonoscopy screening.

    Materials and Methods

    This cross-sectional study was performed on 81 physicians working in academic hospitals of Mashhad University of Medical Sciences, Iran, between February and May 2019. Data were gathered using demographic information checklists and a researcher-developed checklist to evaluate the attitude of physicians towards the benefits and necessity of colonoscopy. Data were analyzed using SPSS software version 23, and p<0.05 was considered statistically significant.

    Results

    81 physicians with a mean age of 58.9±6.6 years were studied. Most of the participants were male (n=60, 74.1%), married (n=79, 97.5%), and had fellowships in their specialty (n=44, 54.3%). When asked about barriers against colonoscopy, most physicians mentioned unwillingness (n=24, 29.6%) and lack of time (n=14, 17.3%). There was no significant association between physicians’ sex and their screening colonoscopy history (p=0.98). Moreover, no significant association was detected between the physicians’ level of education and undertaking colonoscopy (p=0.15).

    Conclusions

    This study revealed that a large number of physicians are not willing to undergo screening colonoscopy despite the fact that they have a positive attitude towards the method. Although physicians are knowledgeable about the benefits of colonoscopy, it is not sufficient, and creating the right cultural context is also needed.

    Keywords: Colonoscopy, Screening, Colon Cancer, Attitude, Physicians, Faculty, Barrier
  • Hossein Keyvani*, Fahimeh Safarnezhad Tameshkel, Mohammad Hadi Karbalaie Niya, Mahshid Panahi, Mehdi Alamrajabi, Zahra Tajik, Naeimeh Roshanzamir, Hossein Ajdarkosh, Farhad Zamani, Behnaz Bouzari Pages 229-234
    Background

    Colorectal cancer (CRC) as a major health problem has increased globally. The etiology of CRC is among the critical issues. Smoking, obesity, and infectious diseases are probable risk factors of CRC. Meanwhile, chronic infections, such as chronic hepatitis B (CHB) is under investigation.

    Objectives

    The aim of the present study was to determine the rate of HBV genome infection in patients with CRC compared with healthy subjects’ colon tissues.

    Materials and Methods

    Archived formalin-fixed paraffin-embedded (FFPE) blocks of 157 patients who underwent total colonoscopy that were referred to hospitals affiliated to Iran University of Medical Sciences, Tehran, IR Iran, were enrolled. They were categorized into 66 CRC cases and healthy colon tissues as the control group. After DNA extraction from FFPE specimens a Syber Green Real-time polymerase chain reaction (PCR) method was carried out. SPSS software version 16 was used for statistical analysis.

    Results

    Of a total of 157 specimens, the mean age ± std. deviation of 66 patients with CRC was 59.3 ± 14.4, and 57.6% (38/66) of them were males. The mean age ± std. deviation of 91 healthy controls was 57.2 ± 14.6, and 57.1% (52) of them were males. By using real-time PCR we found that there were 6.4% (10/157) HBV positive, of them 9% (6/66) had CRC, and 4.4% (4/91) were healthy controls. Different variables did not have any significant differences.

    Conclusions

    Although some studies reported the association between HBV infection and CRC outcome, we could not prove it. It suggests the role of other risk factors in colorectal cancer incidence. Further studies with larger sample size and different study populations are recommended.

    Keywords: Colorectal cancer (CRC), Chronic hepatitis B (CHB), Hepatitis B virus (HBV)