• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.166-171
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• 2013

While high-dose ionizing radiation results in long term cellular cytotoxicity, chronic low-dose (<0.2 Gy) of X- or ${\gamma}$-ray irradiation can be beneficial to living organisms by inducing radiation hormesis, stimulating immune function, and adaptive responses. During chronic low-dose-rate radiation (LDR) exposure, whole body of mice is exposed to radiation, however, it remains unclear if LDR causes changes in gene expression of the whole brain. Therefore, we aim to investigate expressed genes (EGs) and signaling pathways specifically regulated by LDR-irradiation ($^{137}Cs$, a cumulative dose of 1.7 Gy for total 100 days) in the whole brain. Using microarray analysis of whole brain RNA extracts harvested from ICR and AKR/J mice after LDR-irradiation, we discovered that two mice strains displayed distinct gene regulation patterns upon LDR-irradiation. In ICR mice, genes involved in ion transport, transition metal ion transport, and developmental cell growth were turned on while, in AKR/J mice, genes involved in sensory perception, cognition, olfactory transduction, G-protein coupled receptor pathways, inflammatory response, proteolysis, and base excision repair were found to be affected by LDR. We validated LDR-sensitive EGs by qPCR and confirmed specific upregulation of S100a7a, Olfr624, and Gm4868 genes in AKR/J mice whole brain. Therefore, our data provide the first report of genetic changes regulated by LDR in the mouse whole brain, which may affect several aspects of brain function.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5401-5406
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• 2015

Background: Brain metastases are the most common intra-cranial neoplasms. The incidence is on a rise due to advanced imaging techniques. Aims: The objective of the study was to analyse the clinical and demographic profile of patients with brain metastases from primary solid tumors. Materials and Methods: This is a retrospective single institutional study covering 130 consecutive patients with brain metastases from January 2007 to August 2014. Results: Some 64.6% of the patients were females. The majority were in the sixth decade of life. The site of the primary tumor was the lungs in 50.8% of the cases. The overall median time from the diagnosis of the primary malignancy to detection of brain metastases was 21.4 months. Survival was found to be significantly improved in patients with solitary brain lesions when compared to patients with multiple brain metastases, and in patients undergoing surgical excision with or without cranial irradiation when compared to whole brain irradiation alone. The majority of the cases belonged to the recursive partitioning analysis class II group. Whole brain radiation therapy was delivered to 79% of the patients. Conclusions: Most of the patients with brain metastases in the study belonged to recursive partitioning analysis classes II or III, and hence had poor prognosis. Most of the patients in the Indian context either do not satisfy the indications for surgical excision or are incapable of bearing the high cost associated with stereotactic radiosurgery. Treatment should be tailored on an individual basis to all these patients.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.37-40
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• 1983

Whole brain irradiation is one mode in the treatment of brain cancer and brain metastasis, but it might cause brain injury such as brain necrosis. It has been studied whether the dose distribution could be a cause of brain injury. The dose distribution in whole brain irradiated by Co-60 beam has been measured by means of calibrated TLD chips inserted in the brain of Humanoid phantom. The following results were obtained. 1. Dose distribution on each transverse section of the brain was uniform. 2. On the midsagital plane of the brain, the dose was highest in upper portion and lowest in lower portion, varying 8 from 104% to 90%. 3. When the radiation field includes free space of 2cm or more width out of the head, the dose distribution in the whole brain is almost independent of the field width. 4. It is important to determine adequate shielding area and to set shielding block exactly in repetition of treatment.

• Korean Journal of Veterinary Research
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• v.7 no.2
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• pp.13-18
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• 1967

1. Within experimental chromatin, the total protein: DNA ratio did not vary in the same organs of control and irradiated rats. However, the amount of RNA and total protein associated with the DNA varied considerably among the different types of chromatin. In particular, the content of chromatin was the control tissue. RNA and total protein ratio of chromatins from brtain, liver, testis and spleen declined with experimental I organs. 2. There was the same quantitative relationship between the amount of RNA and the amount of histone-protein associated with DNA in chromatin. 3. RNA: DNA ratio of chromatin showed 1.5-2 times increas in the irradiated organs except brain. However, RNA: DNA ratio was decreased in chromatin by irradiation. 4. Histone-protein:residual protein ratio was greatly varied among the organs. However, the effect was not found by irradiation. 5. Priming activity of chromatin showed a higher value in testis and the activity was greater in organs with higher metabolic activity: 6. Inhibition of Actinomycin D is observable in chromatin from testis, liver, spleen and brain declined without relationship between irradiated and non-irradiated conditions. Ammonium sulfate showed increased priming activity by the electrostatic dissociation of DNA and histone in chromatin on the stimulation depending on property of chromatins. 7. It is suggested that the results support a proposal that testis and spleen of highly sensitive to irradiation should an increase in the priming activity whereas brain and liver of lower sensitivity decreased in the activity.

• Journal of Korean Neurosurgical Society
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• v.56 no.6
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• pp.504-508
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• 2014

A 59-year-old male patient had 5-month history of gait disturbance and memory impairment. His initial brain computed tomography scan showed $3.5{\times}2.8cm$ sized mass with high density in the pineal region. The tumor was hypointense on T2 weighted magnetic resonance images and hyperintense on T1 weighted magnetic resonance images with heterogenous enhancement of central portion. The tumor was totally removed via the occipital transtentorial approach. Black mass was observed in the operation field, and after surgery, histopathological examination confirmed the diagnosis of malignant melanoma. Whole spine magnetic resonance images and whole body 18-fluoro-deoxyglucose positron emission tomography could not demonstrate the primary site of this melanoma. Scrupulous physical examination of his skin and mucosa was done and dark pigmented lesion on his left leg was found, but additional studies including magnetic resonance images and skin biopsy showed negative finding. As a result, final diagnosis of primary pineal malignant melanoma was made. He underwent treatment with the whole brain radiotherapy and extended local boost irradiation without chemotherapy. His preoperative symptoms were disappeared, and no other specific neurological deficits were founded. His follow-up image studies showed no recurrence or distant metastasis until 26 weeks after surgery. Primary pineal malignant melanomas are extremely rare intracranial tumors, and only 17 cases have been reported since 1899. The most recent case report showed favorable outcome by subtotal tumor resection followed by whole brain and extended local irradiation without chemotherapy. Our case is another result to prove that total tumor resection with radiotherapy can be the current optimal treatment for primary malignant melanoma in the pineal region.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.4
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• pp.379-383
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• 2014

The purpose of this study is to investigate the effects of silkworm extracts (SWE) on reactive oxygen species formation in mice (C57BL/6). Mice were administrated intraperitoneally with SWE (20 mg/kg/day) for 14 days. All animals were sacrificed 24 hours after the last SWE treatment and then extracted the blood and brain tissue in mouse. The researcher measured several parameters related to reactive oxygen species formation, malondialdehyde (MDA) and hydrogen peroxide ($H_2O_2$) contents in serum, whole brain, cerebral cortex and cerebellum. The results showed that MDA content of pre-SWE treatment was decreased significantly in serum, mitochondrial and cytosolic fraction of whole brain and cerebellum (P<0.01). The $H_2O_2$ content of pre-SWE treatment was decreased significantly in mitochondrial fraction of whole brain, cerebral cortex and cerebellum (P<0.01). These results suggest that SWE plays an important role for inhibition of oxidative damage of cells as well as antioxidant effect, aging delay and cells protected from irradiation.

• Journal of Korean Neurosurgical Society
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• v.66 no.5
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• pp.511-524
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• 2023

Objective : This animal model aimed to compare the rat group that received brain irradiation and did not receive additional treatment (only saline) and the rat group that underwent brain irradiation and received Granulocyte colony stimulating factor (G-CSF) treatment. In addition, the effects of G-CSF on brain functions were examined by magnetic resonance (MR) imaging and histopathologically. Methods : This study used 24 female Wistar albino rats. Drug administration (saline or G-CSF) was started at the beginning of the study and continued for 15 days after whole-brain radiotherapy (WBRT). WBRT was given on day 7 of the start of the study. At the end of 15 days, the behavioral tests, including the three-chamber sociability test, open field test, and passive avoidance learning test, were done. After the behavioral test, the animals performed the MR spectroscopy procedure. At the end of the study, cervical dislocation was applied to all animals. Results : G-CSF treatment positively affected the results of the three-chamber sociability test, open-space test and passive avoidance learning test, cornu Ammonis (CA) 1, CA3, and Purkinje neuron counts, and the brain levels of brain-derived neurotrophic factor and postsynaptic density protein-95. However, G-CSF treatment reduced the glial fibrillary acidic protein immunostaining index and brain levels of malondialdehyde, tumor necrosis factor-alpha, nuclear factor kappa-B, and lactate. In addition, on MR spectroscopy, G-CSF had a reversible effect on brain lactate levels. Conclusion : In this first designed brain irradiation animal model, which evaluated G-CSF effects, we observed that G-CSF had reparative, neuroprotective and anti-neurodegenerative effects and had increased neurotrophic factor expression, neuronal counts, and morphology changes. In addition, G-CSF had a proven lactate-lowering effect in MR spectroscopy and brain materials.

• Radiation Oncology Journal
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• v.2 no.1
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• pp.33-39
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• 1984

One hundred and twenty patients with brain metastases were seen and evaluated in the Dept. of Therapeutic Radiology, Seoul National University Hospital between 1979 and 1983. Of these, 90 Patients received whole brain irradiation with 2,000 ra4 in 1 week or 3,000 rad in 2 weeks for Palliative Purpose and 30 patients failed to complete the planned treatment. Carcinoma of the lung(44 cases), choriocarcinoma(11 cases), breast(8 cases) were common Primary tumors of 90 patients receiving planned treatment. Symptomatic subjective response was obtained in $92\%$ of Patients and meurologic functional improvement was obtained in $42\%$ of patients. Median survival was 6.4 months in patients with complete treatment an·d less than 2 months in Patients with incomplete treatment, overall survival rate at 1 year and 2 year were $26\%,\;16\%$ in Patients with complete treatment and $8\%,\;0\%$ in patients with incomplete treatment. Primary site, extent of metastases and interval from diagnosis of primary tumor to brain metastases were identified as prognostic factors.

• Molecules and Cells
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• v.27 no.2
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• pp.263-268
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• 2009

Gamma knife surgery (GKS) is used for the treatment of various human brain disorders. However, the biological effects of gamma ray irradiation on both the target area, and the surrounding tissues are not well studied. The effects of gamma ray exposure to both targeted and untargeted regions were therefore evaluated by monitoring gene expression changes in the unilateral irradiated (60 Gy) and contralateral un-irradiated striata in the rat. Striata of irradiated and control brains were dissected 16 hours post-irradiation for analysis using a whole genome 44K DNA oligo microarray approach. The results revealed 230 induced and 144 repressed genes in the irradiated striatum and 432 induced and 239 repressed genes in the unirradiated striatum. Out of these altered genes 39 of the induced and 16 of the reduced genes were common to both irradiated and un-irradiated tissue. Results of semiquantitative, confirmatory RT-PCR and western blot analyses suggested that ${\gamma}$-irradiation caused cellular damage, including oxidative stress, in the striata of both hemispheres of the brains of treated animals.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.125-138
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• 1998

Purpose : To evaluate the late effect(3 and 6 months) of cis-diarnrninedichlo-roplatinum(II)(cisplatin) on the radiation brain damage when the cisplatin was intraperitoneally infused immediately after whole brain irradiation in the rats. Materials and Methods : The histolopathological findings of the brain were examined in rat brains at 3 and 6 months after the treatment. The rats were irradiated(20 or 22.5 Gy, RT) or cisplatin was injected intraperitoneally(2,4, or 8mg/kg, CT) and in combined treatment group, cisplatin(2mg/kg) was injected immediately after irradiation(20 or 22.5 Gr). Histopathological examination was done mostly in irradiation or cisplatin alone groups, because the rats in combined group died during experimental period except 2 rats. Results : The rats treated with cisplatin showed marked epithelial vacuolation with perivascular edema and vascular dilatation in choroid plexus at 3 months as well as multifocal necrosis involving fimbria and cerebellar hemispheres at 3 and 6 months. The changes were more prominent in rats with 2mg/kg injection compared to rats with 8mg/kg injection. The rats with RT and combined CT and RT showed characteristic delayed irradiation effects such as focal coagulation necrosis and vascular changes, which were more marked than previous reports Prominent perivascular and leptomenin-geal astrocytic Proliferation was well documented by anti-GFAP antibody. Cisplatin treatment did not enhance the effect of radiation-induced changes of blood vessels and astrocytic proliferation. Conclusion : The focal necrosis was the most consistently noted finding in this study, it suggested the possibility to use this as an evaluation factor for combined effects of RT and cisplatin.