Introducing a simple tissue equivalent anthropomorphic phantom for radiation dosimetry in diagnostic radiology and radiotherapy

       It is important to measure organ dose in diagnostic radiology & radiotherapy. Because measurement on patients has some limitations, phantoms are being constructed to be implemented. One kind of several phantoms which is being used so far is anthropomorphic phantom which is similar to a man. In this work, using human natural bone as phantom skeletal tissue & paraffin plus NaCl (as impurity) as soft tissue substitute an anthropomorphic phantom was constructed which consists of three parts: 1. head & neck 2.torso 3.hip. Phantom dimensions were selected from the standard man. To measure absorbed dose in tissues, at the sites of parotid, thyroid, sternum, diaphragm, abdomen and hip some cylinders were inserted which were constructed from phantom material and had some cavities to insert TLDs in different depths. Due to importance of photoelectric effect in diagnostic radiology & Compton effect in radiotherapy, two important parameters which should be considered in construction of a phantom is effective atomic number and electronic density were6.57& 3.36×1023 electron.gr-1 , respectively

Protective Role of GnRH Antagonist on Chemotherapy-induced Spermatogenesis Disorder: A Morphological Study

Purpose: Anti cancer drugs is one of the most important chemotherapeutic factors which can influence spermatogenesis process and germinal epithelium. Since dividing cells are mainly affected by anticancer drugs, the aim of the present study is to investigate thepreventive effect of GnRH antagonist on spermatogenic defect produced by anticancer drugs. Methods: In the present study thirty adult male mice aging 6-8 weeks were divided into 3 groups as: Control, Experimental 1 and Experimental 2. Experimental 1 group received Cisplatin for 5 days as 2.5 mg/kg intraperitoneally and Experimental 2group received 0.25 mg/kg cetrorelix (GnRH antagonist) one week before cisplatin treatment and continued for 3 weeks. The mice in all groups were sacrificed 35 days after the last injection and testis specimens were fixed in boueins, formaldehyde fixativeand 2.5% Glutaraldehide then prepared for light and electron microscopic examination. Results: Light microscopy (LM) study showed that the number of spermatogonial cells, thickness of germinal epithelium, was decreased in Experimental 1group. Electronmicroscopy revealed that in this group several intercellular spaces appeared between spermatogenic cells and secretory granules in interstitial cells was increased. There were several vacuolated mitochondria and destroyed organelles in spermatogonial cells but inExperimental 2 group condition was similar to control group. Conclusion: These results indicate that the cetrorelix administration before cancer treatment may protect germinal epithelium against side effects of cisplatin

MRI based morphometry of caudate nucleus in normal persons

Because of continuous changing of anatomy, function and metabolism of the human brain, age- related change is a major risk factor in most prevalent neurodegenerative diseases, including Parkinsons and Huntingtons disease. Therefore, knowing patterns of age-related atrophy of brain tissue can identify causes and possible role of diseases in decreasing brain function with age. The aim of this study was to determine the age, sex, and hemispheric differences in volume of the human neostriatum (striatum) nucleus in right-handed healthy humans. This study was performed on 120 normal human subjects (60 males, 60 females) 15–65 years old that was divided into young (<40 years) and old (≥40 years) groups. The sectional brain images obtained via magnetic resonance imaging (MRI) was analyzed and processed using the Image-J software and the caudate volume was calculated using the Cavalieri’s principle. The analyses revealed bilateral age-related changes in the caudate volume of both sexes and the caudate nucleus was significantly smaller in older than younger subjects (P<0.001). There were statistically significant volume differences between males and females (P<0.05) and there was a significant negative correlation between age and volume of the caudate nucleus. Our results provide useful baseline data on age and gender-related changes of caudate volume in neurodegenerative diseases such as Parkinsons and Huntingtons, which has the potential to diagnose neurodegenerative disease before the appearance of typical clinical symptoms. 

Antioxidant effect of genistein on ovarian tissue morphology, oxidant and antioxidant activity in rats with induced polycystic ovary syndrome

Background: Oxidative stress is the most frequent cause of female infertility disorders including polycystic ovary syndrome (PCOS). Genistein as a major component of soybean isoflavone scavenges free radicals by antioxidant activities. Objective: The present study examines the antioxidant effects of genistein on ovarian tissue following experimental PCOS in rats. Materials and Methods: Twenty female Wistar rat were randomly divided into the following groups (n=5 each group): (I) control group (no treatment); (II) induced PCOS (injection of estradiol valerate); (III) genistein-treated non-PCOS (received genistein); and (IV) genistein-treated PCOS groups. The weight of rats were measured and the blood samples collected and centrifuged. The oxidant and antioxidant activity of plasma and ovaries were measured. All rats were sacrificed under anesthesia, and ovaries were collected and weighted. Histological examination and follicular qualitywere assessed by staining. Results: In histological observation, the induced PCOS rats displayed more number of atretic follicles and the follicular quality in genistein-treated rats was similar to the control groups. The plasma and ovaries malondialdehyde levels significantly increased in PCOS rats (p < 0.001), while the total antioxidant capacity levels, glutathione peroxidase, and superoxide dismutase activities significantly decreased (p < 0.001). The plasma and ovary  malondialdehyde levels significantly decreased in PCOS rats that were treated with genistein (p < 0.001) and the total antioxidant capacity (p < 0.05), glutathione peroxidase, and superoxide dismutase activities significantly increased (p < 0.001). Conclusion: Treatment with genistein preserved follicular quality by increasing antioxidant activities and scavenging oxidant levels in PCOS rats. Key words: Genistein, Antioxidant, Ovary, Polycystic, Follicle, Rats

Degenerative Effect of Cisplatin on Testicular Germinal Epithelium

Purpose: The present study was designed to explore the effect of intraperitoneal administration of cisplatin in germinal epithelium of mice. There are few reports on the side effect of cisplatin on spermatogenesis when are used as anticancer drug. Therefore, in the present study the effect of cisplatin on spermatogenesis was evaluated by electron microscopy. Methods: Twenty balb/c mice aging 6-8 weeks was used in this study. The mice were divided into two groups, control and cysplatin treated. cysplatin was injected for five days as 2.5 mg /kg. The mice were sacrificed after 5 weeks and testicular specimens were removed, fixed in boueins, formaldeyd fixative and 2.5% Glutaraldehide then prepared for light and electron microscopic study. Results: Observation with optic microscope in treated group thickness of germinal epithelium was reduced a lot and increased the number of apoptotic cells. In some seminiferous tubules only sertoli cells were observed and nucleus of spermatogony cells was hetrochromatin. The electron microscopic observations showed some irregularity waviness and thickening in basal layer. Also myoid cells of this group were thick and contracted. In this group many apoptotic cells and damaged organelles were seen. Conclusion: It was indicated that cisplatin affected testicular germinal epithelium by both cytotoxic effect and induction of apoptosis

Terminal Deoxynucleotidyl Transferase (TdT) Inhibiti on of Cord Blood Derived B and T Cells Expansion

Purpose: Terminal deoxynucleotidyl transferase(TdT) is a DNA polymerase that is present in immature pre-B and pre-T cells. TdT inserts N-nucleotides to the V (D) J gene segment during rearrangements of genes, therefore, it plays a vital role in the development and variation of the immune system in vertebrates. Here we evaluated the relationship between cytokines like interleukin-2 (IL-2), interleukin-7 (IL-7), and interleukin-15 (IL-15) and TdT expression in cord blood mononuclear cells and also effect of inhibition in the expansion of B and T cells derived from cord blood. Methodes: The cord blood mononuclear cells were cultured with different combination of cytokines for 21days, which they were harvested in definite days (7, 14 and 21) and evaluated by flow cytometry. Results: Our data indicated that TdT expression increased in cord blood mononuclear cells using immune cell key cytokines without being dependent on the type of cytokines. TdT inhibition reduced both the expansion of B and T cells derived from cord blood and also declined the apoptosis and proliferation. Considered together, TdT played an important role in the control of the expansion of B and T cells derived from cord blood. Conclusion: considered together, it was observed that TdT expression was increased by cytokines and TdT inhibition not only reduced B and Tcells derived from cord blood, but it also affected the rate of apoptosis and proliferation

Comparison of ultrastructure and morphology of mouse ovarian follicles after conventional and direct cover vitrification using different concentrations of ethylene glycol

Background: Many attempts have done to improve cryopreservation of mammalian ovaries using simple, economical and efficient technique “vitrification”. Objective: The aim of the present study was to compare the mouse ovaries cryopreservation by direct cover vitrification (DCV) using different concentrations of ethylene glycol (EG) with conventional vitrification methods (CV). Materials and Methods: Ninety NMRI mice were sacrificed by cervical dislocation; their ovaries were divided into three main experimental groups: control or non-vitrified group, CV group and DCV groups with 4, 6 and 8M EG as cryoprotectant. After vitrification-warming, the viability of mechanically isolated follicles and the morphology of ovarian follicles by light and electron microscopes were studied. Results: The normality of primary and preantral follicles in non-vitrified and CV groups were higher than those achieved by DCV groups (p<0.001). The survival rates of isolated follicles in non-vitrified, CV and DCV groups with 4M, 6M and 8M ethylene glycol were 98.32, 96.26, 84.10, 85.46 and 84.56 %, respectively and in DCV groups it was lower than other groups (p<0.001). The ultrastructure of ovarian follicles was well preserved in CV technique. The follicles in DCV groups appeared to have vacuolated oocyte with nuclear shrinkage and irregular distribution of cytoplasmic organelles. Their mitochondria were located mainly in the sub cortical part of the oocyte and the granulosa cells demonstrated some signs of degeneration. Conclusion: DCV of mouse ovarian tissue using only EG has induced some alteration on the fine structure of follicles. The integrity of mouse ovarian tissue was affected by DCV technique more than CV

Morphometric and volumetric study of caudate and putamen nuclei in normal individuals by MRI : effect of normal aging, gender and hemispheric differences

Background: The aim of this study was to determine age, gender, and hemispheric differences in the volume of the human neostriatum (striatum) nucleus in healthy humans. Material/Methods: This study was performed on 120 normal human subjects (60 males, 60 females, right-handed) 15-65 years old, divided into two groups: young (<40 yrs) and old (=≥40 yrs). Sectional brain images were obtained via magnetic resonance imaging (MRI), analyzed and processed using the Image-J software, and the striatum volume was calculated using the Cavalieri's principle, retrospectively. Results: The analyses revealed bilateral age-related shrinkage of the putamen in both genders and the putamen and caudate nucleus were significantly smaller in older than in younger subjects (P-value <0.001). The age-related shrinkage of the caudate and putamen nucleus in men and women was about 5%, 5% and 4%, 4%, respectively, and there were statistically significant volume differences between males and females (P-value <0.05). In both genders, a significant rightward asymmetry was observed in the caudate and putamen nucleus (3.89%, 4.21% in men and 4.51%, 3.32% in women). Conclusions: Bilateral age-related shrinkage and rightward asymmetry of the striate nucleus was found in healthy adults and there were significant volume differences between men and women. Obtained results provide useful baseline data on age and gender-related changes of the volume of the striatum