فصلنامه علوم پزشکی دانشگاه آزاد اسلامی
سال شانزدهم شماره 1 (پیاپی 43، بهار 1385)

Enormous diversities of heavy chain immunoglobulin (IgH) & IgK molecules are generated during B- and T-lymphocyte differentiation through the rearrangement of gene segments. Additionally, random insertion and deletion of nucleotides between gene segments make unique sequences which are cell or clone specific. IgH and IgK gene rearrangements are the most and relatively common reported rearrangements in B-precursor acute lymphoblastic leukemia, respectively. The purpose of this study is to evaluate the pattern of IgH and IgK gene rearrangements using polymerase chain reaction (PCR) in BP-ALL in Iranian children. For this prospective study, bone marrow aspirates of 183 patients with the diagnosis of acute leukemia were collected at admission before any chemotherapy. Having reviewed cytomorphology (L1:44%, L2:41%) and immunophenotyping, only 140 cases with the diagnosis of B-precursor ALL were selected. Mononuclear cells including leukemic blasts were isolated by density gradient. Having DNA extracted, hyper-variable regions of IgH and IgK were amplified by consensus primers using PCR. PCR products were analyzed after heteroduplex analysis and polyacrylamide gel electrophoresis (silver stain). The DNA sequences were compared and aligned to the sequences homologous for IgH and IgK published by Gene Bank. IgH gene rearrangements were found in 114 (90.4%) of patients using consensus primers for CDR-III and CDR-I regions (monoclonal 57.8% biclonal 34.9% oligoclonal 5.5%). Four of nine patients with T-ALL had clonal rearrangements of IgH. Clonal pattern of Igκ-Kde were present in 59 (67%) of cases (biclonal 10%). VKI (25%) and VKШ (22.7%) were the most common type of rearrangements. Clonal rearrangement pattern of IgH gene was similar to other populations. Using FRI and FRIII primers in multiplex PCR increased the rate of detection and reducing turnaround time. IgK was slightly more frequent than previous reports while VKI (25%) was the most common type.

To test whether there is a common site of action for intravenous anaesthetics at the glycine receptor, the effects of binary combinations of thiopentone, pentobarbitone, and methohexitone have been tested on human α1 glycine receptors expressed in Xenopus laevis oocytes using two-electrode voltage-clamp techniques. During this interventional study, recombinant human alpha-1 receptor gene was prepared and the mRNA was injected into cytoplasmic site of Xenopus oocytes. Two-electrod voltage clamp technique used for pharmacological studies of currents of chloride channels (receptors) from the membrane of oocytes. Then, the effect of three barbiturates on currents induced by agonist on the receptors was measured. Thiopentone (5-40mM), and pentobarbitone (25-400mM), (but not methohexitone) potentiated the glycine-induced (50mM) current in a dose-dependent manner, with the maximum potentiation observed to be 220%, and 400%, respectively. In binary combination with thiopentone, or pentobarbitone, methohexitone reduced potentiation compared to that by the individual anesthetics to 180%, and 280%, respectively. Combination of thiopentone and pentobarbitone (50mM) increased potentiation, compared to that by thiopentone alone. Our results indicate that thiopentone and pentobarbitone both act as positive allosteric modulators at the alpha-1 glycine receptor. In contrast, methohexitone has no action alone but acts as a competitive antagonist to thiopentone and pentobarbitone. We suggest that these three intravenous barbiturate anaesthetics share a common site of action at the glycine receptor.

Prolongation of ventricular depolarization time (QRS duration) particularly in left bundle branch block (LBBB) is commonly associated with many cardiac diseases. Electrocardiographic study of QRS duration and electrical axis may be predictors of sever LV systolic dysfunction. In this prospective study that was conducted in CCU and out-patient clinic of Shaheed Beheshti hospital in Babol (2000-2003), 150 patients with the diagnosis of LBBB were assigned in two groups (one QRS≥160 and the other with QRS<160 millisecond.). Then relationship between QRS-duration, left axis deviation (LAD) and echocardiographic LV ejection fraction (EF) were analysed using SPSS software and T-test, chi-square and linear regression analysis in step wise manner. There was no significant correlation between age and gender with duration of QRS and LAD among patients with LBBB (NS). The mean ± standard deviation of EF in the patients with a QRS duration ≥160 millisecond was significantly lower than the mean of EF in the patients with a QRS duration <160 millisecond (%(54.50±10.55) vs. %(23.89±5.47) p<0.001). Pearson correlation between EF and LAD was lower than its value between EF and QRS duration (r=0.378 p=0.006 vs. r=0.926 p<0.001, respectively). Evaluating QRS duration in the presence of LBBB has a significant inverse relation with EF and when its value is greater than 160 millisecond, it could be a simple and appropriate marker of significant left ventricular dysfunction.

Polyvinyl chloride (PVC) is used primarily to produce home appliances however, its production without vinyl chloride (VCM) is not reproducible. VCM has harmful effects on liver when is exposed during a long term duration. We surveyed long term liver effects with exposure of mild to moderate amounts of VCM. In this case-control study, liver enzymes levels of 52 workers were compared with 48 staff employees using t-test analysis. Case group was composed of all occupied workers in PVC production unit (one of the petrochemical complex), while, the control group was chosen form administrative staff of the same petrochemical complex. The mean level of alkaline phosphatase (ALP) and gamma glutamine trans peptidase (GGT) were shown to be significantly differed between the two groups. Other measures such as AST, ALT, and direct and indirect billirubin were revealed to be higher in case group, however, their difference did not reach a statistically significant level. Results revealed that exposure to even low levels of VCM may lead to mild liver cholestatic damage, therefore, use of tests for liver cholestasis such as GGT and ALP for individuals working in PVC production units should be kept in mind periodically.

Alloxan is a potent generative of reactive oxygen species (ROS), which can mediate B-cell toxicity. Reactive oxygen metabolites have been demonstrated to cause apoptotic cell death. The aim of this study was to investigate alloxan-induced morphological alterations in apoptosis. For this experimental study, wistar rats weighed 200 g were chosen and assigned into four groups of five as follows. The treatment rats received alloxan (45, 90 and 135mg/kg intraperitoneally) and control group rats received saline normal. 48 hours following the injection, pancreatic tissue samples were obtained. The selected tissue samples were fixed in 10% formalin solution and then microscopic sections with the thickness of 5-6 micron were prepared and stained with TUNEL method. Meanwhile, at 12-, 24-, 48- and 36-hour intervals blood samples were obtained from all rats to check blood sugar level. Treatment groups showed apoptotic cells in pancreatic beta cells and high blood sugar in biochemistry laboratory test in comparison with controls. Indeed, the mean number of apoptotic cells in five microscopic fields of all treated groups was significantly (p<0.001) higher than the control group. Mechanism of alloxan-induced apoptosis has not been fully understood however, evidences indicate that the pancreatic beta cell damage is mediated through the generation of cytotoxic oxygen free radicals.

Heart diseases represent the most common causes of mortality worldwide. Knowledge towards heart disease and its risk factors is an important pre-requisite for an individual to implement behavioral change leading towards heart disease prevention. The aim of the present study was to determine the effect of education on knowledge of student's parent's towards cardiovascular risk factors. This interventional study was carried out in Tehran 13th district. A well-prepared questionnaire was used to collect initial data. Data analysis was achieved by SPSS software using ANOVA, paired t-test and correlation coefficient. Totally, 432 subjects with the mean age of 34.6±5.9 years took part in our study, of whom 89.1% were householder. The mean knowledge score was significantly differed before and after education (p<0.05). Unfortunately, parent's knowledge of cardiovascular risk factors were not adequate. This study suggests that educational programs can positively influence the knowledge towards cardiovascular risk factors.

The present study survey risk factors of age-related cataract in patients admitted to selective referral centers in Tabriz. Nurses entail a preventive and educative role based on their knowledge and attitude towards the health and illness. This case-control study was carried out using a consecutive sampling. Totally 500 subjects including 250 patients with age-related cataracts and 250 with non age-related cataracts were requested to fill a prepared questionnaire. Results revealed that occupation is a personal risk factor. Meanwhile, working indoors (OR=1.56), not wearing sunglasses (OR=1.63), diabetes mellitus (OR=2.06), hypertension (OR=2.51), use of aspirin (OR=3.89), tranquilizers (OR=2.96) and corticosteroid (OR=2.01) as well as fatty meal were risk factors. On the other hand, age-related cataract was associated with positive family history, smoking, electric shock and head X-ray. Determining risk factors of age-related cataract may pave the way to postpone the morbidity of this disease.

Child abuse has different meanings in different societies however, there is no uniform definition for child abuse. The present study was conducted to survey the relationship between family, emotional, and social factors and child abuse in girl primary schools in Tehran. It was a case-control study. Initial data were obtained using child abuse, family, emotional and social questionnaires. Totally, 1300 primary girl students were randomly selected through districts 2,3,4,7 and 16. Then, 60 students scored higher the cut point were selected as the abused children (the case group) and 60 matched students scored below the cut point were served as the control group. Totally, 78.3% of abused children's fathers and 83.3% of their mothers were alive. These figures were 91.7% and 95% for non-abused children, respectively. Of abused children, 30% were abused with their mothers however, 33.3% of non-abused children were abused with their classmates. Meanwhile, 75% of abused children experienced severe physical violence. There was a significant association between child abuse and the following factors: age, occupation, level of education, economic status, number of children, divorce, drug addiction, social isolation and lack of access to social support. Results have revealed that there was a significant association between child abuse and age, occupation, level of education, economic status, number of children, divorce, drug addiction, social isolation and lack of access to social support.

Use of computer has been increased during the recent years. There are numerous factors affecting computer use in different organizations, while user’s involvement is among the most common influencing issues. The aim of the present study was to assess the relationship between computer user involvement and computer attitude and anxiety in community health centers. It was a descriptive study. Totally, 319 nurses and staff working in community health centers were included. Data were collected using a questionnaire composed of 3 parts: computer user's involvement, attitude towards the computer, and computer anxiety. Results showed that most of the respondents, 86.8%, were women and 11.6% were men. Most of the male candidates (42.9%) aged 45-54 years while most of the females (42.1%) aged 35-44 years. User's involvement induce a positive attitude towards the computer (p<0.0001). Indeed, user's involvement could increase positive attitude toward computer for patient care and patient confidentiality and can reduce computer anxiety (p<0.05). Results have revealed that in the pretest analysis, most of the subjects had a moderate attitude and knowledge, however, following the education, most of the cases acquired suitable attitude and knowledge (p<0.001), while the differences among controls were not statistically significant. For providing successful implementation and development of computerized information systems, user’s involvement is an important issue. Therefore, this factor should be considered by managers.

Neurofibromatosis is a genetic disorder presented with tumoral tissue around a nerve and other pathologic disorders. Neurofibromatosis type I (NF1) is more frequent and involves skin, central nervous system, bone and endocrine glands. Neurofibromatosis type II (NF2) is, however, presented with bilateral acoustic neuroma. Neurofiromatosis type V (NF5) is a rare disorder that has been reported in only 100 cases worldwide and presents with cutaneous neurofibromas with or without skin lesions. In the present article we have introduced 2 females aged 19 and 20 with segmental neurofibromatosis.