مجله دانشکده پزشکی دانشگاه علوم پزشکی تهران
سال هفتاد و نهم شماره 4 (پیاپی 244، تیر 1400)

Classifying patients with low back pain into homogeneous and distinct categories by organizing similar manifestations among individuals can be helpful to attain better results for treatments. Providing homogenous categories of patients with low back pain would improve benefits produced by treatments. To gain a greater understanding of the proposed multi-stage process and validate diagnostic categories, the current research was designed to conduct a review about this process. We aimed to validate movement system impairment (MSI) based categories of people with chronic low back pain. MSI-based classification uses a standardized approach for classifying people with low back pain into 1 of 5 subgroups. For the present narrative review, computerized databases of EMBASE, Google Scholar, MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed and Science Direct were searched for articles published between January 1990 and December 2018. For electronic searches, keywords and terms used were: “Reliability”, “Validity”, “Classification”, “low back pain" and “Human Movement System”. Fourteen full-text research reports that have been undertaken to add clinical, laboratory and outcome validity to MSI-based classification of low back pain were included in the review. Five studies were categorized as clinical validity studies which investigated the accuracy of examinations for patients with low back pain, 5 studies categorized as laboratory validity studies and 4 studies categorized as outcome validity studies which included randomized control trials. The results of this review revealed that novice users can learn the diagnosis algorithm of MSI-based categories of low back pain and by practicing, their inter-tester reliability and precision in applying the classification algorithm would be comparable to that of described for experienced expert raters. The laboratory-based tests, including 3D motion analysis, indicated that there are differences in movement patterns of the lumbar spine between low back pain subgroups. Also, for people with low back pain, classification-specific treatments based on the MSI model resulted in better outcomes. In conclusion, this review indicated the validity of the MSI classification system in people with chronic low back pain.

Posturography is a method in which the postural stability of adults is evaluated by measuring the center of pressure sway. This study aims to evaluate the reproducibility of measuring the center of pressure oscillation in standing position with internal perturbation in healthy young women with and without hyperkyphosis.

Ten women with dorsal hyperkyphosis with the mean age of 23.5±2.65 years and 10 healthy women with the mean age of 21.9±1.3 years (October 2018 to February 2019) were recruited for the study. Subjects were asked to perform rapid bilateral arm elevation while standing on a force plate. Standard deviation of the amplitude and The standard deviation of the velocity of the center of pressure sway in anterior-posterior, Medio-lateral directions and the area of sway were used for statistical analysis. Measurements were carried out by one examiner with a 1-day interval in The Biomechanics laboratory of The School of Rehabilitation Sciences, Shahid Beheshti University of Medical Sciences. The relative reproducibility of the measurements was calculated by Intra-class Correlation Coefficient (ICC), standard error of measurement (SEM) and minimal detectable changes (MDC).

The intra-rater reliability of standard deviation of the center of pressure sway velocity and amplitude of both directions in both groups were more than 0.75. The intra-rater reliability of the area of the center of pressure sway in the healthy and hyperkyphosis group were 0.42 and 0.38 respectively.

Standard deviation of the amplitude and standard deviation of the velocity of the center of pressure sway can be considered as reliable variables for assessing static balance in young women with and without dorsal hyperkyphosis in future studies. However, the inconsistency of sway area especially in women with hyperkyphosis suggests that the use of it for differentiation between subjects and the assessment of the outcome of any interventions on the postural stability should be considered with caution.

Since pulmonary angiography is the only non-invasive method for diagnosing pulmonary embolism, the use of radiation reduction methods without affecting the quality of images seems necessary. One of the simplest reasons for unnecessarily increasing of patient exposure is repetitive imaging due to poor image quality. Therefore, it is necessary to identify and eliminate the factors that reduce the image quality, which leads to duplication of imaging or reduced accuracy.  In this study, the reasons for decreasing the image quality of pulmonary computed tomography (CT) angiography were investigated.

This cross-sectional study was performed over a period of 6 months (May to November 2018) in a university-affiliated hospital. Data of 75 patients suspected of pulmonary embolism who were referred for CT angiography were collected. All CT scans were performed by a 16-slice CT scanner (Lights Speed, GE Healthcare) with fixed imaging parameters including 100 kVp and 100 mA. In order to evaluate the adequacy of pulmonary artery enhancement, the Hounsfield unit (HU) of the main pulmonary artery was measured in the aortic arch, upper, and lower segmental parts. Also, 8 factors affecting the image quality were examined.

The mean HU of the main pulmonary arteries was 312 in the range of 124 to 677. The mean HU in patients with and without pulmonary embolism was 358 and 302, respectively. Most CT images (61%) had poor quality for the diagnosis of pulmonary embolism. Only 2% of the images were acceptable compared to standard images and protocols. Late imaging was the most common quality confounding factor in this study.

A low-quality image reduces the accuracy of the physicianchr('39')s diagnosis that leads to misdiagnosis. Besides, sometimes poor image quality leads to repetitive imaging, which results in increased patient exposure and therefore increased radiation hazards. Therefore, modifiable confounding factors must be identified and corrected which one of the most important ones is wrong imaging timing protocols after contrast injection.

SLC39A6 Protein (solute carrier family 39) or LIV-1 is a zinc transporter protein that is overexpressed in positive estrogen cancers such as breast cancer. The LIV-1 protein transfer zinc into the cytoplasm through the plasma membrane. Today it is known that just as a decrease in the concentration of zinc in the cell can cause cancer, an excessive increase in the concentration of zinc can also stimulate irregular cell division and caused cancer. Thus, inhibition of zinc transporter protein may play a role in preventing malignancies and metastasis. It can also be used as a diagnostic marker in the diagnosis of cancers in various laboratory methods. The present study was performed to prepare a polyclonal camel antibody for the detection of LIV-1 protein at the cell surface.

This study was started in the Pasture Institute of Iran in 2018 September and finished in February 2020. An expression construct containing the human LIV-1 gene was prepared and transferred to the E.coli BL21 by chemical (CaCl2) and heat shock method. The expression of the protein was induced by IPTG and then protein was purified by affinity (Ni-NTA) chromatography. After preparing recombinant protein one female camel was immunized, 6 times at two weeks intervals with Freundchr('39')s adjuvant. After immunization, the isolated polyclonal antibody was evaluated by ELISA, western blotting and flow cytometry in the detection of LIV-1 protein.

The result showed that LIV-1 protein was well purified and also the camel polyclonal antibody was able to detect LIV-1 protein in ELISA, western blot and also it can detect LIV-1 on the cell surface as shown by flow cytometry test.

In recent years, LIV-1 has been shown to be a good candidate as a marker in breast cancer, so polyclonal antibodies against LIV-1 can be used for early detection of breast cancer by various diagnostic methods. In this study, it has been shown that polyclonal camel antibodies can be used in laboratory methods and can be considered for immunological tests and therapeutic applications.

Low-Molecular-Weight Heparin (LMWH) is recommended as the first-line treatment in patients with active cancer and venous thromboembolism (VTE), but many patients prefer to take oral anticoagulants and non-injectable forms with more reasonable price. Venous thromboembolism is a very common comorbidity in patients with cancer. Therefore, the aim of this study was to evaluate the efficacy and safety of the rivaroxaban compared with enoxaparin in patients with cancer and VTE.

This randomized clinical trial was conducted on 50 patients with non-hematologic cancer and deep vein thrombosis (DVP) or pulmonary thromboembolism (PTE) enrolled into Imam Khomeini hospital, from November 2019 to March 2020 in Ahvaz. The participants randomly assigned in two treatment groups (25 patients in each group) of rivaroxaban (15 mg every 12 hours for the first three weeks and then orally at 20 mg daily) or enoxaparin (1 mg/kg by subcutaneous injection every 12 hours) and followed for 6 months to evaluate the efficacy, complications and safety (incidence of recurrent VTE, major bleeding and deaths) of these therapies in Ahvaz.

The three most common cancer diagnoses were breast (n=11, 22%), colon (n=10, 20%), and lung (n=7, 14%). Major bleeding at 6 months was only seen in one patient (4%) in the enoxaparin group and did not occur in the rivaroxaban group (P>0.05). Minor bleeding occurred in 1 patient (4%) in the rivaroxaban group and did not occur in the enoxaparin group (P>0.05). One patient in the enoxaparin group died because of fever and neutropenia. The prevalence of DVT and PTE in cancer patients was not significantly different based on patient age (P=0.154), gender (P=0.430), BMI (P=0.490), underlying disease (P=0.294), smoking (P=0.955), type of cancer (P=0.527), and metastatic cancer (P=0.280).

The results of this study suggest that the efficacy of rivaroxaban is not less than that of enoxaparin and therefore can be a potential option for patients with non-hematologic cancer and VTE. However, further randomized, controlled trials are needed to confirm these results.

Wound healing is a complicated process involving the proliferation of the epithelial cells, deposition of granulation tissue as well as recruitment of inflammatory cells. It also is a hot topic of research for trauma, orthopedics and general surgery studies. There are many forms of cells involved in this process. This study aimed to design a tissue-engineered wound dressing consisting of chitosan fibers containing silver ion bioactive nanoparticles for wound healing.

The present study is an experimental study that was conducted in the research laboratory of the Department of Biology of Mohaghegh Ardabili University from April to November 2019. All experiments of this study have been performed under the ethical guideline of Helsinki and in accordance with the Ethics Committee of the Mohaghegh Ardabili University of Ardabil (Iran). The wound dressing of nanofibers was prepared by the sol-gel method. Cytotoxicity was assessed by MTT assay. Then the antimicrobial properties of nanofibers were determined by the disk diffusion method. SEM and AFM images were obtained from nanofibers. Finally, nanofibers were analyzed by the FTRI method.

Results of the prepared tissue-engineered wound dressing consisting of chitosan fibers containing silver ion-doped bioactive nanoparticles showed that cytotoxicity was at an appropriate level. The nanofibers prepared with 2% silver nanoparticles produced a 10 mm inhibition zone against Staphylococcus aureus and a 9 mm inhibition zone against Escherichia coli. Therefore, the best percentage of scaffolds in the present study was 2%. Also, results of the SEM micrographs and AFM image analysis of the scaffolds showed that the nanofibers had good roughness and a proper structure for cell seeding and attachments. Besides that, FTIR analysis also showed that the prepared nanofibers had standard bonds.

Chitosan-Silver nanoparticles scaffold have antimicrobial activity on Gram-negative and positive bacteria. The results of the toxicity test also showed that it did not have much toxicity on the cultured cells. Therefore, it can be considered for therapeutic applications, such as wound dressing.

Multiple Sclerosis (MS) is one of the most debilitating disease among young adults. Understanding the disability score (Expanded Disability Status Scale (EDSS)) of these patients is helpful in choosing their treatment process. Calculating EDSS takes a lot of time for Neurologists, so having a way to estimate EDSS can be helpful. This study aimed to estimate the EDSS score of MS patients using statistical models including Artificial Neural Network (ANN) and Decision Tree (DT) models.

This cross-sectional study was performed on MS registry study data of Kermanshah province from April 2017 to November 2018. From the total data available in the registry system, The 12 variables including demographic information, information about MS disease and their EDSS score were extracted. EDSS scores were also estimated using ANN and DT models. The performance of the models was compared in terms of estimation error, correlation and mean of an estimated score. Data were analyzed using Weka software version 3.9.2 and SPSS software version 25 with a significance level of 0.05.

In this study, 353 people were studied. The mean age of the patients was 36.47±9.1 years, the mean age of onset was 9.2±30.34 years, the mean duration of the disease was 6.20±5.7 years and the mean EDSS score was 2.46±1.8. Estimation errors in the DT model were lower than in the ANN model. The real EDSS score was significantly correlated with scores estimated by DT (r=0.571) and ANN (r=0.623). The mean EDSS estimated by the DT model (2.46±1.1) was not significantly different from the real EDSS mean (P=0.621) but the mean EDSS estimated by the ANN model (2.87±1.3) was significantly higher than the real EDSS mean. (P<0.05).

The DT model could better estimate the EDSS score of MS patients than the ANN model and made predictions that were closer to the actual EDSS scores. Therefore, the DT model can accurately estimate the EDSS score of MS patients.

lumbar disc degeneration is a multifactorial degenerative disease which is affected by genetic inheritance and environmental factors. Type XI collagen is important for organization of the extracellular matrix and cartilage collagen construction. Rs1676486 is a SNP that causes the conversion of C-T, resulting in a change in the expression of the collagen 11 alpha chain. The T allele reduces the alpha 1 chain transcription of collagen 11 and ultimately leads to an imbalance in gene expression.

This study aims to determine the genetic variant of alpha1 type11 collagen is associated with the progress of intervertebral disc degeneration. All patients were selected from the AL-Zahra Hospital of medical university of Isfahan, Iran, between April 2016 and September 2017. SNP rs1676486 of alpha1 type11 collagen was genotyped in 100 patients and 100 healthy controls. The inclusion criteria for patients were: individuals who had typical clinical and imaging symptoms and signs of intervertebral disc degeneration. Exclusion criteria were: patients with trauma, metabolic and neuromuscular diseases, and congenital disorder of the spine. The Genomic DNA was extracted from peripheral blood samples by a Whole Blood Genomic DNA Extraction Kit. The chi-square test and fisher’s exact test were evaluated to determine differences of genotype and allele distributions between intervertebral disc degeneration patients and healthy controls. To compare the relationship between genotypes and clinical features the Mann-Whitney U test was used.

The mean age was 39.54±9.52 years for the patients and 28.14±5.32 years for the controls, respectively. The mean BMI were 26.3±3.18 kg/m2 and 27.3±3.52 kg/m2 for the patients and the controls, respectively. In addition, the results showed that the prevalence of surgical disc in patients with L4-L5 levels was 52.1% and L5-S1, with 31.1%. This study showed, rs1676486 in alpha1 type11 collagen gene was associated with modified intervertebral disc degeneration at age ≤50 years and this gene increases intervertebral disc degeneration risk at age >50 years. SNP rs1676486 had the significant association with the intervertebral disc degeneration (P=0.019), and patients were found to have higher frequency of AA than the controls.

This observation shows that type XI collagen is related to age and genetic factor in intervertebral disc degeneration disease.

Long-term and intensive physical exercise can change the function of different cells in the immune system in athletes, predisposing them to viral infections such as coronavirus disease (COVID-19). The purpose of this brief report was to provide protocols related to the immune system in athletes to prevent infectious diseases.

To examine immune system responses to sports activities, articles were collected from all databases: Science Direct, PubMed, Scopus, Web of Science, Springer, Google Scholar, SID, and the most recent articles were selected.

High-intensity and long-term physical exercise can be effective in suppressing immune responses. Therefore, moderate-intensity exercise can be an effective strategy. Maintaining the function of the immune system in athletes was dependent on nutritional strategies, sleep control, stress management, and strict adherence to proper exercise principles and health protocols. Athletes are more prone to viral infections in the early hours after strenuous, prolonged physical exercise; and they should be limited in contact with people who may increase their risk of infectious diseases. We should mention that moderate-intensity physical exercise can improve the function of immunoglobulins, anti-inflammatory cytokines, neutrophils, natural killer cells, cytotoxic T cells, and immature B cells. Maintaining social distance, especially immediately after strenuous exercise, is also recommended for athletes due to the increased risk of infectious diseases. The immune system has been considered an effective part of sports activities in athletes in recent years. The prevalence of viral diseases such as COVID-19 has not been and will not be for the first and last time in life. Therefore, using questionnaires and initial monitoring (adherence to diets, corona testing, adherence to health protocols) can be the first step.

Finally Due to the pandemic of coronary heart disease and its unknowingness, providing some health and nutrition guidelines for starting exercises and sports competitions to prevent the transmission of this disease is on the agenda of this article.

The median nerve is one of the most important branches of the brachial plexus. Due to the role of the median nerve in sensory and motor innervation of the forearm and hand in the upper limbs, its blood supply is very important. Awareness of variations in the blood supply pattern to this nerve reduces the incidence of necrosis and ischemia of the nerve during surgical and diagnostic procedures.

During routine dissection of the cadaver of a 65-year-old man fixed in formalin (10%), in the Department of Anatomy and Reproductive Biology, Shahid Beheshti University of Medical Sciences, a rare variation was observed in the median nerve nutritional artery at the distal end of the left forearm. After dissection of the skin, superficial and deep fascia, anterior compartment forearm muscles, nerves and blood vessels were exposed from surrounding tissues. The median nerve passed through the two heads of the pronator teres muscle and left the cubital fossa in the depth of the flexor digitorum superficialis and the surface of the flexor digitorum profundus in the forearm. It was observed that at the distal end of the left forearm between the flexor carpi radialis and the flexor digitorum superficialis, a relatively thick branch originates from the radial artery and supplies blood to the median nerve. This branch was separated from the radial artery (before the artery enters the anatomical snuffbox) and crossed the surface of the flexor carpi radialis muscle and inserted into the median nerve sheath. In the forearm, this branch was the only artery supplying blood to the median nerve.

Due to the superficial position of the median nerve at the distal end of the forearm, physical damage to the nerve and its nutritional artery leads to necrosis and ischemia of the nerve, and ultimately disturbed the transmission of sensory and motor messages.