Iranian Journal of Basic Medical Sciences
Year:2005 | Volume:8 | Issue:1 (25)|Papers Count:12

In radiotherapy, wedge filters are used to modify iso-dose curves and hence optimize tumor dose distribution in patient. To deliver prescribed dose, timer or monitor unit should be involved the dose with no wedged field and wedge factor. Therefore, any variation of wedge factor due to treatment parameters will affect the deliver dose to patients.Effects of field size, SSD and depth of treatment on wedge factor were studied, using universal wedge filters with nominal angles of 30°, 45° and 60°, a hand made water phantom 21×21×10 Cm and a 0.6 cc Farmer ionizing chamber, at different SSD and depth from the water surface. Wedge factors were calculated as the ratio of charge (nC) of the wedge to open beam, measured by and an electrometer model NE2571, while the dosimeter was irradiated for 60s with Picker ATC9 60Co unit.Except for 60° wedge filter, with 95% certainty, there is no meaningful relation between wfs with field size and depth. For 60° wedge filter, variation of wf for situation used in this study is about 0.55% per Cm×Cm variation in field size and 0.28% per Cm variation in depth. An inverse linear relation between wf and SSD approved with 95% certainty. Variations of wf for 30°, 45° and 60° wedge filters, for situation used in this study are 0.11%, 0.18% and 0.33% per Cm variation in SSD respectively.Dependence of wfs to FS, depth and SSD for 60o wedge filter were formulated and shows that the field size and depth of treatment has a negligible effect on wedge factor. Correction of wf for SSD, which has a large domain of variation, is appreciable in clinical usage (more than 5%) and for 60o wedge filter can be calculated as: wfc=wf [1- 0.0033(SSD-80)]   65<SSD<85 Cm

Investigation has shown that folic acid supplementation during the critical period of pregnancy is associated with a decrease in the incidence of skeletal, craniofacial and nervous system malformations; and decreasing folic acid during pregnancy results in a range spectrum of malformations. In this study we used an animal model, which displays focal cortical dysplasia around the secunda fissure of cerebellum. This malformation results from ectopic granule cells which proliferate locally just around the bottom of the secunda fissure. Although there are few studies about the effects of folic acid in prevention the risk of neural tube defects, the objective of the present study was to determine whether folic acid is able to decrease the incidence of focal displasya which possibly results from mutation in gene, Cfp-1 located on chromosome 4. If so, there may be a correlation between consumption of folic acid and laminine expression with reduction of percentage of this malformation.Young female C57BL/6J mice were kept under normal conditions and diet and mated. Next day after mating, finding the vaginal plug was designated as day zero of pregnancy and they were divided in three groups. Experimental group 1 received 0.1 mg/kg folic acid from days 7-10 of gestation; experimental group 2 received the same volume of normal saline on the same days; and the control mice were kept untreated. Each group consisted of 8, 7 and 9 animals respecectively. Pregnant mice from gestational days (E17 to E18) to postnatal days (PD 1 to 5) were sacrificed and collected in formaline-acetic-alcohol or 3.7% paraformaldhyde, serially sectioned and stained with Cresyl violet; and selected sections on PD 1 (the day before formation of malformation) were incubated with monoclonal antibody (anti-laminin). Our findings showed that the percentage of malformations decreased significantly in experimental group 1 (13.8%) compared to experimental group 2 and controls. The rate of laminin expression in folic acid exposed by special regards to secunda fissure increased significantly. These data provide evidence for the ability of folates and their important roles in preventing mice from central nervous system defects. These data might also have significance for human malformations as well.

In this study, adenosine and cyclohexyladenosine (CHA) were tested for possible anti-tumor activity using potato disc assays.MIC of adenosine and CHA were determined using microplate method. In potato disc assay, discs were cut of potato with specific diameter and transferred on 1.5% agar under a laminar air cabinet. 50 ?l of a mixture containing suspension of Agrobacterium tumefaciens and the solution of agents were inoculated on potato discs in plates. The plates were incubated in 25 °C for 21 days until the tumors were counted. Adenosine and CHA did not show any anti-bacterial activity. The IC50 values of adenosine and CHA against tumor were 93.78 and 19.56 µM, respectively. DPCPX (A1 selective adenosine receptor antagonist) inhibited the anti-tumor activity of adenosine and CHA, while itself did not show any effect against potato disc tumors. This study indicates that adenosine and CHA have anti-tumor activity, and this effect is mediated via A1 receptor exists in potato cell or A. tumefaciens.

Allergic reactions to plant pollens are a common problem. There are some evidences that saffron pollen has allergenic properties. Although IgE-mediated hypersensitivity has been reported, other immunologic mechanisms may be involved based on a variety of clinical manifestations in allergic cases. One of the mechanisms that have been suggested is specific IgG and its subclasses. In this study, an Enzyme-linked Immunosorbent Assay (ELISA) was developed for detection of specific IgG subclasses against saffron pollen extract. Briefly, microtiter plates were coated with crude extract of saffron pollen and then blocked with bovine serum albumin (BSA), and the sera were added to the plates which followed by the addition of anti-human IgG. TMB was used as substrate. Finally, after stopping the reaction with addition of HCl, plates read at 450 nm. The method was verified by testing two groups of samples, first, sera from individuals living near saffron farms in Khorasan and second, sera from individuals living in areas not having any saffron farms. The results indicated significant differences between the two groups.

Cryptosporidium spp. is an obligate intracellular protozoan parasite (protozoa, apicomplexa) that has been recognised worldwide as a major cause of gastrointestinal disease in a variety of mammalian hosts, including human. Cryptosporidium primarily infects epithelial cells of the gastrointestinal tract, resulting a variety of problems ranging from acute, self-limiting diarrhea to fatal cases in immunocompromised persons, particularly those with aquired immunodeficiency (AIDS). Regarding to the public health importants of this parasite, isolation and purification of Cryptosporidium spp. is essential for the detection of antigenic characterization and characteristic of various strains. In the present study, a total 480 samples from calves were collected in Isfahan province. 30 of these samples were infected with Cryptosporidium by using the Scheather’s flotation and Modified Ziel-Nelson Acid Fast methods. Fecal samples containing Cryptosporidium were purified using sucrose gradient centrifugation and were stored in 2.5% potassium dichromate solution at 4 °C.Techniques for the large-scale isolation of cryptosporidium oocytes and sporozoites, obtained from the feces of infected calves, were developed employing discontinuous sucrose gradients and isopycnic percoll gradients. The oocyst recovery method utilized 2 sequential discontinuous sucrose gradients followed by 1 percoll gradient. Recover oocytes were essentially free of debris and bacteria and represented 34% of the orginal oocyst suspension. Sporozoites were recovered from excystation mixtures on single percoll gradient. Sixty-three peacid analysis.

Finger and hand prints are formed during the late first and second trimester of fetal development, and then remain unchanged. Schizophrenia is a psychotic disease that coexists with structural and biochemical changes of CNS. It is probably under the influence of environmental and/or genetic factors. There are some suggestions that disturbance in the dermatoglyphic patterns are probably in relationship with the appearance of schizophrenia. It seems that this disturbance appears in the first and second trimesters of fetal development, which is a critical period for CNS growth. We have studied the dermatoglyphic changes in 91 schizophrenic patients (49M, 42F) in Ebne Sina Psychosis Hospital of Mashhad, and have compared them with those of 72 healthy controls (42M, 30F). The x2 test was used for quantitative and T-test for qualitative data analysis. The results showed a significant reduction of TABRC between healthy and patient .The forms of Loop and Arch are heterogeneous and compared to the control group were significant (P=.0/04 ,P=0/036). In conclusion, these results provide further evidence that abnormal dermatoglyphic patterns exist in some patients with schizophrenia, and that, the a-b ridge count can be used as a marker of this psychotic disease, and support the idea that the incidence of schizophrenia maybe due to the adverse intrauterine events. Because these events probably affect the brain, behavior and finger print patterns, dermatoglyphics would be a proper method for prognosis of some cases of schizophrenia

Teucrium polium (locally known as chez or kalporeh in Khuzestan Province, Iran) is used traditionally as remedy for treatment of headache, convulsion and dysmenorrheal; and also its hypoglycemic, hypolipidemic and antibacterial effects has been reported. But its spasmolytic effect on uterine smooth muscle remained to be identified. The aim of the present study was to investigate the effect of Teucrium polium aqueous extract (TPAE) on virgin rat uterus contractions evoked by some stimulants. Freshly dried aerial parts of plant were extracted. Contractile responses were recorded isometrically in an organ bath containing Tyrode’s or De Jalon solutions under 1g initial tension. Results indicated that extract (0.125, 0.25, 0.5, 1, 2, 4 and 8 mg/ml) reduced the uterus contractions induced by KCl (60mM), oxytocin (10mU/ml) and BaCl2 (4mM) dose dependently and significantly (P<0.0001). The spasmolytic effect of extract was totally reversible in less than 10min. The spasmolytic effect of TPAE was unaffected by L-NAME (300 and 100 µM) in KCl- or oxytocin-induced contractions receptively. Spasmolytic effect of extract was unaffected by propranolol (1µM for 5 min) in KCl-induced contractions but, reduced significantly in oxytocin-induced contraction. In normal calcium De Jalon solution, the contractions-induced by BaCl2, were more attenuated by extract than in calcium free solution. The data presented seem to suggest that the spasmolytic effect of Teucrium polium aqueous extract is partially induced via blocking the voltage dependent calcium channels and remaining effect is through involvement of the 3-adrenoceptors and stimulating the cAMP synthesis. In this inhibitory effect, NO is not involved.

Carnitine is a vital biologic substance transporting fatty acids into myocytes and facilitates fatty acids -oxidation for energy production.There is little findings about its cardio protective effects on cardiac arrhythmias during ischemia / reperfusion. So in this study, effects of L-Carnitine on cardiac arrhythmias in the ischemic reperfused isolated rat hearts were investigated.Male Sprague-Dawley rats (270-330g) divided into 4 groups randomly and were anesthetized by Sodium Pentobarbital (50-60 mg/kg-ip). The hearts were removed and quickly mounted on a Langendorff apparatus and were perfused by a modified Krebs-Henseleit solution under constant pressure at 37 C. In control group (n=6), the hearts were perfused only by normal Krebs -Henseleit solution at stabilization, 30 min regional ischemia and 30 min reperfusion time, while in the treated groups (n=6 in each group), the hearts during ischemia / reperfusion were perfused with 0.5,2.5 and 5mM/L of L-Carnitine - enriched Krebs-Henseleit solution. ECG was recorded during the experiment. During ischemia and reperfusion, cardiac arrhythmias were analyzed based on Lambeth Convention. At the ischemic phase, number, duration and incidence of Ventricular Tachycardia (VT) were decreased with doses of 2.5 and 5mM/L L-Carnitine (p<0.05).L-Carnitine in doses of 2.5 and 5mM/L reduced the number of VT considerably (p<0.05) at the reperfusion phase. But duration of VT was not decreased significantly. Total Ventricular Ectopic Beats (VEBs: Single + Salvos + VT) also were reduced in treated groups by 0.5-5mM/L of L-Carnitine (p<0.05). However, single VEBs and duration of Reversible Ventricular Fibrilation (Rev VF) were decreased only by 5mM/L L-Carnitine. There were no significant differences between control and treated groups in the time to onset of Rev VF and incidences of VF and VT at the reperfusion phase.Considering these results, we conclude that L-carnitine has a protective effect against ischemia reperfusion injuries as a reduction of cardiac arrhythmias.

Since several evidences exist that the nucleus paragigantocellularis (PGi), located in the rostral ventrolateral medulla, is one of the major afferent to the nucleus locus coeruleus (LC), in this study the effect of reversible anesthesia of PGi nucleus with 4% lidocaine (0.5µl/rat) on local EEG amplitude of LC and behavioral signs of morphine-induced witdrawal was investigated. The local EEG amplitude of LC nucleus was significantly decreased by administration of lidocaine in control and morphine-dependent rats. Also, in LC nucleus of morphine-dependent rats, the amplitude and behavioral signs increased significantly following administration of naloxone (10mg/kg; s.c.). In addition, microinjection of lidocaine into the PGi before administration of naloxone reversed the local EEG amplitude of LC to the amount of controls and decreased the behavioral signs of withdrawal syndrome, significantly. There was no significant change in the amplitude in morphine-dependent rat after chronic exposure to morphine than before. These results indicated that during withdrawal syndrome, activation of LC neurons and behavioral signs of it likely arise from PGi nucleus and are mediated by LC neurons. In addition, no changes in the amplitude of LC and/ or elsewhere were appeared in LC activity. The findings are consistent with the hypothesis that during morphine withdrawal, there is an increased in unit activity of the PGi afferents to the LC or an increased release of excitatory transmitter from their terminals in the LC.