Tehran University Medical Journal

A parasitological study of blood, skin, and alimentary tract of conventionally maintained laboratory mice and rat

Baharak Akhtardanesh

Background: Efforts have been made worldwide to identify and to study parasites of laboratory animals, aiming at the achievement of proper procedures for eradication of parasitic infestations, considering the important role of these animals in scientific research. There is no sufficient data about parasitic infestations of Laboratory animals which are kept in conventional systems in Iran. In this scope, peresent study was designed to investigate the presence of ectoparasites and endoparasites in conventionally maintained laboratory rats (Rattus norvegicus) and in mices (Mus musculus).
Methods: A descriptive cross-sectional study was performed on 240 randomly selected rats and mice from two different animal houses in Kerman city, Iran. Skin scraping blood samples and alimentary tract contents of all animals were fully examined for the presence of parasitic infections.
Results: In the first animal house, Nosopsylla fasciatus (flea), Hymenolepis dimminuta, Entamoeba muris and Cryptosporidium spp. infestation were diagnosed respectively in 35.41%, 36.1%, 3.57%, and 1.25% of rat colonies but only Entamoeba muris infestation was detected in 4.58% of mice colonies. In the second animal house, 2.5% and 2% of rat and mice colonies were infected by Entamoeba muris.
Conclusion: Based to presence of asymptomatic parasitic infection in conventionally maintained laboratory animals, regular periodical samplings, precise sanitary monitoring of barrier maintained system, environment and food seem necessary in animal houses. Eradication of parasites could eliminate the confounding effects of these infections on researches and additionally decrease the risk of zoonotic disease transmission to investigators and animal house personnel's.

Association study between HLA-DRB, HLA-DQA1, HLA-DQB1 and breast cancer in Iranian women

Majid Mahmoodi

Background: Based on the reports, high frequency of special alleles of HLA class II genes might be associated with susceptibility to or protective from a particular cancer. These alleles might vary depending on the geographical region. Here we investigate the association between alleles of HLA class II genes and breast cancer in Iranian women.
Methods: 100 patients with pathologically proved breast cancer who referred to Cancer Institute, Tehran University of Medical Sciences in Tehran, Iran, were divided to two groups based on ages (40 years old and less/ or more than 40 years old) and were randomly selected and compared with a group of 80 healthy blood donor subjects. HLA class II alleles were determined by amplification of DNA with polymerase chain reaction (PCR) method followed by HLA-typing using sequence-specific primer (SSP) for each allele.
Results: The most frequent alleles in the DR and DQ regions in group 1 (40 years old and less) in comparison with control group were HLA-DQA1*0301 (p=0.002) and HLA-DQB1*0302 (p>0.05). In contrast HLA-DQA1*0505 (p=0.004) had significantly lower frequency in this group compared with control group. Patients of group two (more than 40 years old) had a higher frequencies of HLA-DQA1*0301 (p=0.001) and HLA-DRB1*1303 (p=0.02) and a lower frequency of HLA-DQA1*0101 (p=0.002) compared to healthy control.
Conclusion: These findings provide information of a positive and negative association between certain alleles of HLA class II and breast cancer in our population and also might support that the pattern of inheritance in the early and late onset of breast cancer differ substantially.

Serum pneumolysin antibody and urinary pneumococcal antigens (Binax) level in children with upper respiratory tract infection versus normal controls

Samileh Noorbakhsh

Background: Streptococcus pneumoniae is a common cause of respiratory infection. Pneumococcal upper respiratory tract infection (URTI) in children is seldom bacteremic. Determination the prevalence of S.pneumoniae infections in children with URTI using rapid urinary antigen test (BINAX now) and titration of serum pneumolysin antibody (added to conventional culture) was the object of this study.
Methods: A cross sectional, case-control study done in ENT & pediatric departments of Rasoul Hospital in Tehran, Iran, (2008 -2010) upon 133 cases with upper respiratory tract infection (otitis media, sinusitis and tracheitis). The nosocomial infection omitted in first step. 60 remaining cases followed for S.pneumoniae infection by culture and rapid urinary antigen test (Binax Now). Serum pneumolysin antibody titers compared between 45 cases and 66 controls.
Results: Positive culture (S.pneumoniae, H.influenza) obtained in 4/60 URTI cases. Positive urinary S.pneumoniae antigen detected in 50% (30/60) of cases and 6% (4/66) of controls (p=0.01). The pneumolysin antibody level with cut-off level 525pg/ml was higher in URTI cases than controls (982±441 Vs. 525±42, p<0.0001). Area under the ROC curve for pneumolysin antibody was 0.923 (95%CI 0.86-0.97, p<0.0001) and had 87% sensitivity and 82% specificity for differentiation between cases and controls.
Conclusions: The high pneumolysin antibody level in cases with URTI strongly indicates the pneumococcal infection. Pneumolysin antibody level even in little amounts (525pg/ml) with 87% sensitivity and 82% specificity is a suitable test for diagnosis of pneumococcal infection in children with URTI, but this test should be added to conventional culture (gold standard) and rapid urinary antigen test.

Comparison of Septocolumellar Suture (SCS) and Lateral Crural Overlay (LCO) methods on nasal tip projection and rotation in rhinoplasty

Ghasemali Khorasani

Background: Proper nasal tip control is a difficult step in rhinoplasty. The aim of this study was to compare the effects of two cartilage modifying methods, Septocolumellar Suture (SCS) and Lateral Crural Overlay (LCO), on nasal tip projection and rotation.
Methods: In a single-blinded clinical trial, 36 patients who were scheduled for nasal tip deprojection were enrolled. A profile photograph of face was taken from all the patients before and three months post operation. Nasofacial angles, TP:Ln ratio for assessing nasal tip projection, tip columellar angle and nasolabial angles for nasal tip rotation assessment were measured by a computer software. The patients were randomly divided into two groups that underwent open rhinoplasty.
Results: Both the LCO and SCS methods were accompanied by a significant reduction in nasofacial angle and TP:Ln ratio, there was raised nasolabial and rotation angle in comparison to preoperative values. The use of LCO method in comparison to SCS resulted in more increase in the nasolabial angle (11.83±3.05 Vs. 4.56±1.62 degree) and Rotation Angle (11.44±3.22 Vs. 1.56±1.04 degree) and resulted in more reduction in post-operative TP:Ln ratio in comparison to preoperative measures (-0.05±0.01 Vs. -0.03±0.01), however, the difference in the nasofacial angle was not significant.
Conclusion: Both cartilage modifying techniques resulted in significant reduction in the projection and increasing in the tip rotation. Lateral Crural Overlay (LCO) seems to be more effective than Septocolumellar Suture (SCS). Therefore, the SCS method is recommended for patients who need more nasal tip rotation and deprojection in rhinoplasty.

3-Dimentional radiotherapy versus conventional treatment plans for gastric cancer

Maryam Moshtaghi

Background: The current standard of adjuvant management for gastric cancer after curative resection based on the results of intergroup 0116 is concurrent chemoradiation. Current guidelines for designing these challenging fields still include two-dimensional simulation with simple AP-PA parallel opposed design. However, the implementation of radiotherapy (RT) remains a concern. Our objective was to compare three-dimensional (3D) techniques to the more commonly used AP-PA technique.
Methods: A total of 24 patients with stages II-IV adenocarcinoma of the stomach were treated with adjuvant postoperative chemoradiation with simple AP-PA technique, using Cobalt-60. Total radiation dose was 50.4Gy. Landmark-based fields were simulated to assess PTV coverage. For each patient, three additional radiotherapy treatment plans were generated using three-dimensional (3D) technique. The four treatment plans were then compared for target volume coverage and dose to normal tissues (liver, spinal cord, kidneys) using dose volume histogram (DVH) analysis.
Results: The three-dimensional planning techniques provided 10% superior PTV coverage compared to conventional AP-PA fields (p<0.001). Comparative DVHs for the right kidney, left kidney and spinal cord demonstrate lower radiation doses using the 3D planning techniques (p<0.0001), the liver dose is higher (p=0.03), but is still well below liver tolerance.
Conclusion: Despite the department protocol using conventional planning, 3D radiotherapy provides 10% superior PTV coverage. It is associated with reduced radiation doses to the kidneys and spinal cord compared to AP-PA techniques with the potential to reduce treatment toxicity.

Correlation between FEF25-75/FVC ratio and methacholin challenge test in diagnosis of bronchial hyperresponsiveness

Khatereh Amiri

Background: Because bronchial hyper responsiveness (BHR) has been shown to be a risk factor for asthma and lung function decline, interest has focused on diagnosing BHR. The aim of our study was to measure the association between airway caliber relative to lung size expressed as the ratio between forced expiratory flow, mid expiratory phase, divided by forced vital capacity (FEF25-75/FVC) and BHR measured by methacholine challenge test (MCT) to obtain a cutoff for this ratio and positive MCT.
Methods: We carried out a cross- sectional study on general Iranian population in 376 subjects aged 7-73 years who were referred to Shariati hospital in Tehran, Iran in an outpatient setting. There were 190 male (50.5%) and 186 female (49.5%) subjects. They had chronic respiratory symptoms such as cough and dyspnea. The physical examination was normal. Baseline spirometry was normal or equivocal. MCT was done for all subjects over a two year period (2009- 2010). Positive MCT was defined by PC 20≤4mg/ml.
Results: The methacholine challenge test was positive in 191 (50.8%) and negative in 185 (49.2%) patients. The mean of FEF25-75/FVC in positive MCT was 0.86±0.27 Vs. 0.91±0.28 in the negative ones (p=0.070). The sensitivity and specificity of FEF25-75/FVC for prediction of MCT results were 57.1% and 60.2% based on cutoff point of 0.85 in all patients, and 87.5% and 70.7% based on cut off point of 1 in allergic patients, respectively.
Conclusion: The FEF25-75/FVC appears to be a useful predictive ratio in allergic patients but not in general population.

Serum homocysteine level and gall stone disease: a case control study

Reza Afghani

Background: Gall stone is an important health problem in the world for which different risk factors have been characterized. Gall stone and cardiovascular disease have common risk factors. Homocysteine is accepted as one of the risk factors for cardiovascular disease. We aimed to study the effect of homocysteine level on gall stone formation.
Methods: 54 patients with gall stone-related diseases and 54 patients without stone (control group) were studied from January 2007 to December 2008. Control group consisted healthy subjects with ultrasound proven normal gallbladder. Serum homocysteine level was checked in both groups. Homocysteine level of equal or more than 15 mmol/l was considered as abnormally high.
Results: Cases included 43 women (79.6%) and had mean age of 50.76±15.23 years. Homocysteine level was significantly higher in patients with gallstone in comparison to control group (p=0.014). Risk of gall stone increased 3.4 times in persons who have homocysteine level equal or greater than 15mmol/l (p=0.019). The mean level of homocysteine was higher in men than women (p=0.03). The mean level of homocysteine did not differ significantly in patients with simple gallstone and patients with gallstone-related inflammation disorders (cholecystitis, cholangitis, and pancreatitis). Additionally, one unit increase in BMI level was associated with 1.12 times increase in the risk for gall stone formation (p=0.035).
Conclusion: The homocysteine level is increased in patients with gall stone-related diseases. Homocysteine may be considered as a risk factor of gall stone formation.

Acute necrotizing mediastinits: a series of four patients

Mohsen Eshraghi

Background: Acute Necrotizing Mediastinitis (ANM) is a lethal disease that without antibiotic therapy and surgical Intervention has a mortality rate about 40% in best medical centers. With development of imaging technology (spiral CT- Scan) and shortening in time of diagnosis and surgery, the outcome and prognosis of the patients are improved. The surgical modalities are trans- cervical and trans- thoracic approaches.
Case series: We present a series of four patients with acute necrotizing mediastinitis that admitted to thoracic surgery ward in vali-e-asr Hospital in Tehran, Iran, during years 2009 and 2010. A 31years old woman and three male patients with ages 21, 25 and 63 years. Odontogenic infection was the cause in two cases while pharyngeal perforation and cervical esophageal perforation were the causes of acute necrotizing mediastinitis the others.
Results: Mean±SD of hospitalization time was 24±6 days. Infection of cervical space (periviceral spaces) and the superior mediastinum were found in all patients while extension of infection below the carina was found in two of them. All patients were operated by trans- cervical approach. One patient was operated by trans- thoracic approach. All patients were discharged with good general condition.
Conclusion: Early usage of spiral CT- scan for diagnosis of acute necrotizing mediastinitis and early drainage with trans- cervical approach could be life saving in acute necrotizing mediastinitis patients with good results.

Bickerstaff’s brainstem encephalitis: a case report

Mansoureh Toghae

Background: Bickerstaff's brainstem encephalitis (BBE) is a very uncommon central nervous system disease with unknown etiology. As it is usually responsive to treatment, the diagnosis this disease is important. It seems There is no reported Bickerstaff's brainstem encephalitis case in Iran.
Case presentation: An 83 year old woman presented with vertigo, ataxia and dysarthria from a week prior to admission. Her T2 weighted MRI revealed high intensity lesions in the pons area. She received treatment with impression of ischemic stroke. After few days, lower extremities became weak symmetrically and deep tendon reflexes depressed. Deep sensory loss was noted too. The EMG-NCV studies showed acute polyneuropathy and in CSF examination increased protein content was noted. The patient improved after IVIG and corticosteroid therapy with impression of Bickerstaff's brainstem encephalitis.
Conclusion: In spite of severe initial presentation, Bickerstaff's brainstem encephalitis has a good prognosis if it diagnosed and treated properly. Although clinical features is too important, but paraclinical work up are necessary to diagnose this syndrome.

Seyed Ahmad Alinaghi

No abstract###