Survival curves were constructed from dose-incidence curves for apoptosis in the crypts of mouse small intestine, using the number of apoptotic cells after high doses (N{sub M}) as maximum cell population size. The mean lethal doses (D{sub 0}) for the dose range 0-0.5 Gy were calculated for each time of day. A circadian rhythm in both D{sub 0} and N{sub M} values was detected, indicating that both the number and sensitivity of radiation-induced apoptosis were changing throughout the day. (author).
Inactivation of the RB tumor suppressor and activation of the MYC family of oncogenes are frequent events in a large spectrum of human cancers. Loss of RB function and MYC activation are thought to...Full Text Available
Ionizing radiation is a standard treatment for various human solid tumors. However, several clinical studies showed that a significant proportion of patients undergoing radiotherapy for hepatocellular carcinoma (HCC) develop intrahepatic and extrahepatic metastasis. Understanding of radiation-induced cancer cell invasiveness and behavior is essential and of great important for developing suitable treatment strategies to contain cancer spread. Therefore, in this study we evaluated the effectiveness of using swept source optical coherence tomography (SS-OCT) to monitor the enhancement of HCC cell invasiveness by radiation. SS-OCT images were acquired and recorded to obtain three-dimensional data sets per four hours in 48 hours after irradiating HepG2 cells with 7.5 Gy. The cell migration behavior in three-dimensional tissue models was quantified from images of radiation-induced and sham-irradiated cells.
The effect of exposure to gamma rays on LPO contents in liver, spleen and kidney of mice and the anti-lipid-peroxidation of preparations of chinonin, tannic acid and squalene were reported. All these preparations were given by intragastric perfusion. For LPO, a modified method of TBA spectrophotometry was used for determination. The results show that LPO contents in tissues increased 72 h after whole-body exposure of mice to gamma rays, that in range of 0-4 Gy, there was a linear relationship between radiation doses and LPO contents, and that all three preparations were effective in reduction of the LPO content in liver, spleen and kidney of mice, with chinonin (at dose of 0.35 mg/mouse#centre dot#day) being more effective than tannic acid (at dose of 15 mg/mouse#centre dot#day) and squalene (at dose of 0.6 mg/mouse#centre dot#day).
This study was carried out to evaluate the biochemical and morphological effects of ionizing radiation on ovary. Immature mice (ICR, 3 week-old) were irradiated at a dose of LD{sub 80(30)} at KAERI. The ovaries were collected after 6 hours, 12 hours, 1 day, and 2 days post irradiation. To analyze the morphological changes, histological staining with hematoxylin-eosin, immuno- histochemical preparation using in situ 3'-end labeling was performed. DNA fragmentation analysis and flowcytometric evaluation of DNA extracted from whole ovary were performed. As a result of DNA fragmentation analysis, DNA fragments with 185, 370, and 555 base pairs were clearly shown at 6 hours post irradiation. The percentage of A{sub 0} cell cycle was significantly increased in the irradiated group than control. In situ 3'-end labeled follicles were increased at 6 hours post irradiation. The radiation-induced follicular atresia was taken place via an apoptotic ...
Previous behavioral and pharmacological studies have implicated endorphins in radiation-induced locomotor hyperactivity of the C57BL/6J mouse. However, the endogenous opiate(s) responsible for this behavioral change have not been identified. The present study measured beta-endorphin-like immunoreactivity (beta-END-LI) in brain, blood, and combined brain and pituitary samples from irradiated and sham-irradiated C57BL/6J mice. After radiation exposure, levels of beta-END-LI decreased significantly in the brain. A similar, but not statistically significant, decline was measured in combined brain and pituitary samples. Concentrations of blood beta-END-LI were not changed by irradiation. These radiogenic changes in beta-END-LI are in some ways similar to those observed after other stresses. However, radiation-induced locomotor hyperactivity may be mediated more by alterations of beta-END-LI in the brain than in the periphery. ...
We have been investigating radiation-induced neoplastic transformants of C3H 10T1/2 mouse fibroblasts for evidence of heritable changes. C3H 10T1/2 cells were treated with 8 Gy X rays. After approximately 8 weeks of culture, type II/III foci were isolated from the monolayer using cloning rings. Cell lines developed from these foci, and clones established from these cell lines, were examined for DNA content. The isolated focus-derived populations and derived clones often display aneuploidy and/or polyploidization. In one instance a clone (derived from a single cell) displayed multiple polyploidies. During passage the ploidy of many of the anomalous populations gradually reverted to the ploidy of the non-neoplastically transformed state. The morphological features associated with the neoplastic transformation event were nevertheless retained. The results demonstrate that exposure to radiation can induce, in association with morphological ...
The process of mouse skin tumor formation is subdivided into three operational stages. These stages include initiation, promotion and progression. Ionizing radiation has been found to be a weak initiating agent in the production of malignant squamous cell carcinomas, a complete carcinogen and an agent effective in causing tumor progression. Four skin tumor histologies have been seen with ionizing radiation: benign papillomas, squamous (SCC) and basal (BCC) cell carcinomas and fibrosarcomas. Distinct non-ras transforming genes have been detected in radiation initiated SCCs. A benign papilloma cell line (308) was used as a model system to study ionizing radiationinduced progression. A variant 308 cell line (308 10 Gy 5) derived by irradiation of the parental 308 cell has been characterized. The 308 10 Gy 5 cells unlike the parental 308 cells from malignant tumors in athymic nude mice upon subcutaneous injection. The variant ...
In experiments designed to detect new mutations affecting hemoglobin, we irradiated the male or female parent in reciprocal crosses of two mouse strains that differ in alleles at the hemoglobin (Hba, Hbb) loci as well as at five other specific loci. Offspring were analyzed for hemoglobin properties (electrophoretic pattern, solubility, crystal pattern), serum albumin differences, erythrocyte lysis, reticulocyte count, and external appearance. Five hemoglobin variants were found among the mutants. In three, the genetic contribution from the irradiated father was not expressed with regard to the #alpha#-chain; one carried a tandem duplication (the first known case in the mouse) involving Hbb; and one probably resulted from double nondisjunction of chromosome 7. The finding that major chromosome aberratios can mimic hemoglobin mutations indicates the need, in similar experiments, to follow F_1 screening with thorough cytogenetic analysis. The ...
Cancer cells recruit monocytes, macrophages and other inflammatory cells by producing abundant chemoattractants and growth factors, such as macrophage colony-stimulating factor (M-CSF/CSF-1) and monocyte chemoattractant protein-1 (MCP-1/CCL2), to promote tumor growth and dissemination. An understanding of the mechanisms that target cancer cells and regulate tumor microenvironment is essential in designing anticancer therapies. Here, we showed that serum amyloid-A (SAA) and cathelicidin (LL-37) stimulated M-CSF and MCP-1 expression with or without lipopolysaccharide (LPS) administration; conversely, lipoxin-A4 (LXA4) and annexin-A1 (ANXA1) inhibited LPS-induced M-CSF and MCP-1 production by human (HepG2) and mouse (H22) hepatocellular carcinoma cells (HCCs). The effects of LXA4, ANXA1, SAA ...
Mitotic delay is described as a classical response to radiation; however, circadian rhythmicity in cell division in vivo has not been considered by many authors. The present study investigated the relation between fluctuations reported as mitotic delay and recovery in vivo and circadian oscillations in mitotic index in mouse corneal epithelium. One aspect involved single doses (approximately 600 rad) given to mice at different circadian stages. The normal circadian rhythm in cell division was never obliterated. Inhibition of mitosis was evident but unpredictable, ranging from 6 to 15 hr after irradiation. Recovery was evident only during the daily increase in mitotic index of controls. The classical interpretation of recovery from mitotic delay may be in an in vitro phenomenon not reflecting in vivo responses, which are apparently strongly circadian stage dependent. The second portion of the study demonstrated a dose-response effect on length of mitotic delay and, ...
Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has very limited therapeutic options. Recently, it has been found that hyaluronic acid (HA) shows selective binding to CD44 receptors expressed in most cancer histotypes. Since the trend in cancer treatment is the use of targeted radionuclide therapy, the aim of this research was to label HA with rhenium-188 and to evaluate its potential use as a hepatocarcinoma therapeutic radiopharmaceutical. Methods: {sup 188}Re-HA was prepared by a direct labelling method to produce a ReO(O-COO){sub 2}-type coordination complex. {sup 188}Re-HA protein binding and its stability in saline, phosphate buffer, human serum and cysteine solutions were determined. Biokinetic and dosimetric data were estimated in healthy mice (n=60) using the Medical Internal Radiation Dose methodology and mouse model beta-absorbed fractions. To evaluate liver toxicity, alanine aminotranferase (AST) and ...
BackgroundTo investigate the significance of Aurora B expression in hepatocellular carcinoma (HCC).MethodsThe Aurora B and Aurora...Full Text Available
Full text: The general population is daily exposed to chronic, low doses of ionizing radiation (IR) from both natural and artificial sources. The biological consequences of acute, high dose IR exposure can be readily determined; however, the nature and significance of low dose, low dose-rate IR effects are still the subject of debate. Confounding the issue, are the phenomena collectively referred to as the Radiation-induced Bystander Effect (RIBE). The RIBE describes a collection of in vitro observations that suggest the presence of a soluble, transmissible factor(s) released from irradiated cells that can induce a biological response in un-irradiated cells. The induction, nature and magnitude of the RIBE varies between cell culture systems, radiation sources and end-points measured. Efforts to confirm the presence of the RIBE in vivo have been confined to in vivo-like culture systems and limited work with tumour and bone-marrow transplantation models. Validation ...
The present study was designed to assess the radioprotective effects of amifostine on ovarian follicles. Three week-old female mice with or without pretreatment of amifostine were irradiated with 6.42 Gy of #gamma# -ray. Ovaries were collected 0 and 6h after irradiation. DNA fragmentation pattern and expression of genes and activity of proteins related with apoptosis were investigated by means of RT-PCR and Western blot. Proliferation of granulosa cells was reduced and incidence rate of follicular atresia was increased in ovarian follicles in #gamma# -ray irradiated mice compared to those in control or amifostine-treated group. DNA fragmentation was increased in time-dependent manner in granulosa cells of all irradiated groups. However, no difference between amifostine pre-treated group and irradiated groups was found and the expression of p53 as tumor suppressor gene and Bax as one of pro-apoptotic Bcl-2 family was increased in irradiated mice ovaries. PARP as DNA damage sensor was ...
Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to ...
Treatment with sorafenib prolongs both the median survival and time to progression by nearly 3 months in patients with advanced hepatocellular carcinoma. Although the effects of combining sorafenib...Full Text Available
Transcatheter arterial chemoembolization (TACE) has become the standard treatment modality for unresectable hepatocellular carcinoma (HCC). Nonetheless, the clinical outcomes in patients with unresectable...Full Text Available
Hepatitis B virus (HBV) is clearly a factor in the development of hepatocellular carcinoma, but its mechanism of action remains obscure. One possibility is that the HBV integration event alters the...Full Text Available
Background:Liver resection of large hepatocellular carcinomas (HCC), measuring at least 10 cm remains a controversial debate. Multiple studies on HCCs treated with surgical resection...Full Text Available
For many years, epidemiological studies have demonstrated a strong link between chronic hepatitis B virus (HBV) infection and the development of primary hepatocellular carcinoma (PHC). Other hepatocarcinogens...Full Text Available
The National Cancer Institute Laboratory of Human Carcinogenesis is seeking statements of capability or interest from parties interested in collaborative research to further develop, evaluate, or commercialize a gene signature for prognosis of hepatocellular carcinoma in patients.
Hepatocellular carcinoma (hcc) is an uncommon tumour, but its incidence is increasing in Canada and elsewhere. Currently, there are no Canadian recommendations for diagnosis and treatment of...Full Text Available
Hepatocellular carcinoma (HCC) is one of the most critical global health issues. With frequent association of viral liver disease, HCC is highly complex, harboring both cancer and chronic liver disease....Full Text Available
γ-Radiation-induced tumors of Arabidopsis thaliana L. have been produced as a novel approach to isolation of genes that regulate plant development. Tumors excised from irradiated...Full Text Available
Development of mouse models representing human spontaneous ovarian cancer has been hampered by the lack of understanding of the etiology of this very complex disease. Mouse models representing the different...Full Text Available
A 38 year old male dentist developed an oligodendroglioma of the left medial temporal lobe and parasellar region 12 years after radiotherapy with 6600 rads for acromegaly. The 30 cases of radiation-induced gliomas reported in the English literature are reviewed and analysed. The criteria for defining radiation-induced tumours of the central nervous system are proposed as follows: the tumour has a long quiescent ''latency period'', a location in the previously irradiated field, a verified histological difference from a primary condition, and does not arise from a primary condition associated with a genetic syndrome such as neurofibromatosis or tuberous sclerosis. The reported case fulfilled these criteria but appears to be the only reported radiation-induced oligodendroglioma.
AbstractThe elucidation of the human and mouse genome sequence and developments in high-throughput genome analysis, and in computational tools, have made it possible to profile entire...Full Text Available
To capitalize on the response of tumor cells to ionizing radiation, we developed a controlled-release nanoparticle drug delivery system using a targeting peptide that recognizes a radiation-induced...Full Text Available
Purpose: This paper reviews and reassesses the internationally accepted niches or ‘targets’ in bone marrow that are sensitive to the induction of leukaemia and primary...Full Text Available
IntroductionIrradiation of normal, non-malignant bone during cancer therapy can lead to atrophy and increased risk of fracture at several skeletal sites, particularly...Full Text Available
PurposeRadiation-induced heart disease (RIHD) is a severe side effect of thoracic radiotherapy. This study examined the effects of PTX and α-tocopherol on...Full Text Available
IntroductionRadiotherapy outcomes might be further improved by a greater understanding of the individual variations in normal tissue reactions that determine tolerance. Most published...Full Text Available
By using EPR measurements of radiation-induced radicals it is possible to utilize human fingernails to estimate radiation dose after-the-fact. One of the potentially limiting factors in this...Full Text Available
Epizootics of neoplasms in freshwater fish species are considered in relation to circumstantial and experimental evidence that suggest that some epizootics of neoplasia of hepatocellular, cholangiocellular,...Full Text Available
Monolithic N-channel junction field effect transistors (NJFETs) dc characteristics, small signal parameters and noise have been studied from 300 K down to cryogenic temperatures before and after irradiation with {sup 60}Co {gamma}-rays and fast neutrons (1 MeV). Radiationinduced effects on dc parameters and noise are reviewed. Noise spectral density measurements performed at various temperatures have shown that the radiationinduces a noise increase which is temperature and frequency dependent. (orig.). 14 refs.
The resistance of six tropical hardwoods to fungal degradation by two wild-type strains of Phanerochaete chrysosporium Burdsall was investigated using vermiculite burial and wood-block weight loss techniques. Radiation-induced wood-polymer composites (WPC), based on two hardwoods Ramin and Rubberwood with methyl methacrylate, were prepared, and samples were also exposed to the wood-rotting fungus. A significant improvement in resistance to fungal decay was observed in the WPC. Scanning-electron micrographs of the two woods and their composites after fungal degradation are presented and discussed.
The results of theoretical and experimental investigations, describing the effect of ionizing radiation on wood and its main components and methods for production of wood-plastic composites by means of radiation-induced chemical modification are generalized. Domestic and foreign experience in their production is systematized; physico-mechanical characteristics of new material, simulation and calculation of irradiating devices, as well as calculation and experimental study of #gamma#-radiation attenuation both by wood material and by wood of different species are given. Gamma sources ("6"0Co isotope, a hot loop of a nuclear reactor) as well as electron accelerators are considered as ionizing radiation sources.
Polytetrafluoroethylene was obtained by radiationinduced polymerization of tetrafluoroethylene in acetone at 195 K. An average diameter of the products was very small compared with commercial one; it was about 0.3 micro-meters. The yield was reached to 100% with a dose of 4 kGy. The crystallinity of the products is decreasing with increasing dose. The products become amorphous, for higher irradiation doses. It was found that PTFE obtained by irradiation of TFE in acetone at 195 K has branching structure. This was demonstrated by means of "1"9F MAS NMR. (Author)
The electronic structure of the clusters (V/sub 3/Si/sub 4/)/sup 12 -/, (Nb/sub 3/Sn/sub 4/)/sup 12 -/(Mo/sub 3/Ge/sub 4/)/sup 15 -/ in crystalline V/sub 3/Si, Nb/sub 3/Sn, Mo/sub 3/Ge compounds is calculated by the Extended Hueckel method. The influence of different types of radiationinduced defects on the density of states at the Fermi level (the anti-site defects, the displacement of atoms in linear chains, the vacancy-interstitial type defects) is considered.
The electronic structure of the clusters [V_3Si_4]"1"2"-, [Nb_3Sn_4]"1"2"-[Mo_3Ge_4]"1"5"- in crystalline V_3Si, Nb_3Sn, Mo_3Ge compounds is calculated by the Extended Hueckel method. The influence of different types of radiationinduced defects on the density of states at the Fermi level (the anti-site defects, the displacement of atoms in linear chains, the vacancy-interstitial type defects) is considered. (author).
We reported a relevant activity of the combination between sorafenib and octreotide long-acting release (LAR) in advanced hepatocellular carcinoma (HCC) patients. In this work, we have studied if oxidative...Full Text Available
This opinion presents an overview of recent developments in the diagnosis and treatment of hepatocellular carcinoma (HCC) in Japan. The use of Ethiodol (iodized ethyl ester of the fatty acid of poppyseed oil) for hepatic angiography in diagnosing and treating (combined with chemotherapeutic agents) HCC has been reported. Ethiodol has been found to localize in HCC and remain there for long periods. The implications of these findings are discussed.
Background: the fact that therapeutic irradiation can induce significant stenosis in the arteries of the head, neck, and chest, as welt as in the aorta and the iliac arteries, is familiar in daily practice and well documented in the literature. By contrast, radiation-induced renal artery stenosis seems to be a less widely known complication. Patients and methods: the sudden onset of medically refractory arterial hypertension and coma in a 27-year-old man is reported, who had been treated at age 20 with chemotherapy and radiotherapy for Ewing's sarcoma in the lumbar region. This treatment had been performed at the hospital of Sion, Switzerland in 2001. Also, the relevant literature from 1965 to 2007 is reviewed to underscore various aspects of this problem and to demonstrate the clinical relevance of renal artery stenosis as a potential long-term sequela of radiotherapy. Conclusion: radiation-induced renal artery stenosis has only rarely been ...
Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that inhibit the expression ...
Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that inhibit the expression ...
Mouse genetic resources include inbred strains, recombinant inbred lines, chromosome substitution strains, heterogeneous stocks, and the Collaborative Cross (CC). These resources were generated through...Full Text Available
The mouse is the leading organism for disease research. A rich resource of genetic variation occurs naturally in inbred and special strains owing to spontaneous mutations. However, one can also obtain...Full Text Available
Mouse lines with behavioral phenotypes relevant to symptoms in neurodevelopmental disorders may provide models to test hypotheses about disease etiology and to evaluate potential treatments....Full Text Available
The Pde6brd10 (rd10) mouse has a moderate rate of photoreceptor degeneration and serves as a valuable model for human autosomal recessive retinitis pigmentosa...Full Text Available
BackgroundThe dystrophin glycoprotein complex is disrupted in Duchenne muscular dystrophy and many other neuromuscular diseases. The principal heterodimeric partner of dystrophin...Full Text Available
A new strain of mouse hepatitis virus (MHV) was isolated from pooled gut suspensions from an epizootic of lethal enteritis in newborn mice. Negative-contrast electron microscopy showed an abundance...Full Text Available
Recently, there has been significant progress in the development of genetically-engineered mouse (GEM) models. By introducing genetic alterations and/or signaling alterations of human pancreatic cancer...Full Text Available
The first cell lineage specification in mouse embryo development is the formation of trophectoderm (TE) and inner cell mass (ICM) of the blastocyst. This article is to review and discuss the...Full Text Available
Normal mouse epidermis constitutively expresses prostaglandin-H synthase 1 (PGHS-1) but no PGHS-2. Acute inflammation and epidermal hyperplasia, (hyperplastic transformation), as evoked in adult mouse...Full Text Available
The cellular receptor for murine coronavirus mouse hepatitis virus (MHV)-A59 is a member of the carcinoembryonic antigen (CEA) family of glycoproteins in the immunoglobulin superfamily. We isolated...Full Text Available
Recombinant mouse UDP-glucose pyrophosphatase (UGPPase), encoded by the Nudt14 gene, was produced in Escherichia coli and purified close to homogeneity. The...Full Text Available
Reaggregated cells from 6- to 8-day-old mouse cerebella have been used to raise antibodies in rabbits. The interaction of these antibodies with cerebellar cell surface components was assessed by cytotoxicity...Full Text Available
In preimplantation mouse development, the first cell lineages to be established are the trophectoderm (TE) and inner cell mass. TE possesses epithelial features, including apical-basal cell polarity...Full Text Available
Transgenic mouse models have contributed considerably to our understanding of the cellular and molecular mechanisms by which androgens control spermatogenesis. Cell-selective ablation of the androgen...Full Text Available
Radiofrequency electromagnetic fields (EMF) are harmful to public health, but the certain anti-irradiation mechanism is not clear yet. The present study was performed to investigate the possible protective effects of green tea polyphenols against electromagnetic radiation-induced injury in the cultured rat cortical neurons. In this study, green tea polyphenols were used in the cultured cortical neurons exposed to 1800?MHz EMFs by the mobile phone. We found that the mobile phone irradiation for 24?h induced marked neuronal cell death in the MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-tetrazolium bromide) and TUNEL (TdT mediated biotin-dUTP nicked-end labeling) assay, and protective effects of green tea polyphenols on the injured cortical neurons were demonstrated by testing the content ...
Abstract: The ability of melatonin as a potent antioxidant was used as a rationale for testing its antiapoptotic ability in normal cells. Recently, melatonin was shown to possess proapoptotic action by increasing reactive oxygen species in certain cancer cells. The modification of radiation-induced apoptosis by melatonin and the expression of apoptosis-associated upstream regulators were studied in normal mice splenocytes and Jurkat T leukemia cells. C57BL/6 mice were exposed to a single whole body X-ray radiation dose of 2 Gy with or without 250 mg/kg melatonin pretreatment. The Jurkat cells were divided into four groups of control, 1 mm melatonin alone, 4 Gy irradiation-only and melatonin pretreatment before irradiation. The highest level of apoptosis in the normal splenic white pulp was...
The radiationinduced reactions in LDPE in the presence of phenolic type antioxidants have been studied. It was shown that various antioxidants can influence the polyethylene network formation and the radical yield in different ways. The dependence of network structure on absorbed doses was determined by gel analysis, hot-set test and extraction of antioxidants for samples irradiated with accelerated electrons. It was found that the antioxidants eluted from polyethylene in higher percentage influence polymer crosslinking to a smaller degree. The ESR studies of #gamma#-irradiated blends of polyethylene with antioxidant indicate the presence of alkyl and phenoxyl radicals. The role of antioxidant molecules on radiationinduced reactions in polyethylene-antioxidant systems is considered. The correlation between the network structure and the type of additive in polyethylene is also discussed. (author).
The formation of nanoparticles during the radiation-induced chemical reduction of silver ions, copper ions, and nickel ions in films based on poly(acrylic acid)-poly(ethylenimine) complexes are studied via electron microscopy. This approach allows preparation of composites containing nanoparticles that are randomly distributed in the polymer matrix and materials with a regular spatial distribution of nanoparticles across the film thickness and in subsurface layers. The structure of metal-polymer hybrid materials is dependent on the irradiation conditions, the type of reduced metal ions, and their initial content in polymer matrices. The ratio between the rate of nucleation and the rate of growth of nanoparticles in the matrices of interpolyelectrolyte complexes depends on the intensity of ...
Miriplatin, a cisplatin derivative with a high affinity for iodized oil, is a novel chemotherapeutic agent designed for use in the transarterial treatment of hepatocellular carcinoma. This case report...Full Text Available
BackgroundGlycochenodeoxycholate (GCDA) is one of the major human bile salts. Bile salts stimulate cell survival and proliferation through the mitogen-activated protein kinase, but...Full Text Available
BackgroundTransarterial chemoembolization (TACE) therapy is an effective locoregional treatment in hepatocellular cancer (HCC) patients. For early modification of therapy, markers...Full Text Available
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. We have investigated whether common cellular DNA domains might be rearranged, possibly...Full Text Available
Using plasma glutathione S-transferase measurements hepatocellular integrity was assessed in groups of hyperthyroid and hypothyroid patients before and after treatment. Ten of 14 hyperthyroid patients...Full Text Available
... protein is abundant in cytosolic portions of malignant epithelial tissue (Fig. 3A). In contrast, the degree of CCTβ staining in normal epithelial tissue (Fig. 3B) or connective tissues was much weaker ......
ContextResponse Evaluation Criteria in Solid Tumors [RECIST (unidimensional)], World Health Organization [WHO (bi-dimensional)] and European Association for Study...Full Text Available
BackgroundHepatitis C virus is a major cause of chronic liver diseases which can lead to permanent liver damage, hepatocellular carcinoma and death. The presently available treatment...Full Text Available
Chromosomal translocation, deletion, and inversion/duplication directly linked to hepatitis B virus (HBV) DNA integration occur frequently in host DNA of human hepatocellular carcinomas. To test the...Full Text Available
BackgroundTo compare the differences in dose-volume data among coplanar intensity modulated radiotherapy (IMRT), noncoplanar IMRT, and helical tomotherapy (HT) among patients with...Full Text Available
The discovery that hepatitis B virus (HBV) integrates into host chromosomes raises the question of whether such viral DNA integration correlates directly with the activation of specific oncogenes or...Full Text Available
Here we describe a Sleeping Beauty (SB) transposition system that utilizes a conditional SB transposase allele, which can be activated by Cre...Full Text Available
Hepatocellular carcinoma (HCC) is a primary malignancy of the liver, which is closely related to hepatitis C and cirrhosis. The molecular mechanisms underlying the hepatocarcinogenesis induced by HCV...Full Text Available
Sixty-six cases of histologically proven hepatocellular carcinomas (HCC) were studied by MRI. Detectability was better by MRI than by CT, especially in the tumor under 2 cm in diameter. The capsule was detected in all cases of HCC over 3 cm in diameter. The capsule was able to be diagnosed only by dynamic MRI study in some cases. High intensity on the T1-weighted image and iso or low intensity on the T2-weighted image suggested that the nodule was adenomatous hyperplasi (AH) or well differentiated HCC. MRI is concluded to be an essential modality in the diagnosis of HCC. (author).
While bone metastases producing photon deficient defects on bone scintigraphy have previously been reported, this finding has not been emphasized for hepatocellular carcinoma (HCC). Furthermore, ''filling-in'' of such photon deficient defects with 67Ga at skeletal sites of metastatic HCC has not been described. In this case report, the combination of a photon deficient defect on bone scintigraphy and avid accumulation of 67Ga in this same area was of value in confirming the diagnosis of metastatic HCC.
Pulmonary embolism complicated by transcatheter arterial chemoembolization (TACE) in known to be due to the use of large amount of lipiodol as an embolic agent. To our knowledge, massive tumoral pulmonary embolism following TACE and confirmed by surgery has not been described in the literature. In this report, we detail the cas of a 49-year-old man in whom cyanosis and hypotension developed abruptly on the day of TACE.. Chest CT revealed diffuse low-attenuated lesions in both pulmonary arteries. Histopathological specimens after emergent pulmonary arterial embolectomy confirmed the presence of massive tumor emboli of hepatocellular carcinoma.
The incidence of hepatocellular carcinoma (HCC) is increasing in developed countries and the general status of HCC patients is now by far better than a few years ago, allowing physicians to propose some different treatments of these patients. Among these treatments, intra-arterial injection of 131-iodine-labelled Lipiodol could be used in palliative, curative or adjuvant settings. After a brief summary of the modalities of this treatment, requiring the collaboration of Gastro-enterologists, Oncologists, Radiologists and Nuclear Medicine physicians, the different possibilities of therapeutic uses of this new approach are described and an outlook of these developments is proposed. (author)
Several compounds were evaluated in nonhuman primates for their potential to induce neoplasms, especially hepatocellular carcinoma (HCC). The compounds can be classified into three groups: food contaminants, model rodent carcinogens, and nitrosamines. All three compounds in the food contaminants group, namely, aflatoxin B1, sterigmatocystin, and methylazoxymethanol acetate, induced HCC. None of the model rodent carcinogens tested consistently induced HCC in rhesus and cynomolgus monkeys. Three of four nitrosamines evaluated induced HCC in rhesus and cynomolgus monkeys. One nitrosamine, diethylnitrosamine, is a predictable and potent inducer of HCC and is useful for establishment of a nonhuman primate model for numerous oncologic studies.
We demonstrated that the intensity levels and lifetimes of two-photon autofluorescences (2PAF) in human liver tissues can be exploited to diagnose hepatocellular carcinoma (HCC). Excited by an infrared femtosecond laser, we suppressed the two-photon autofluorescences of most endogenous fluorophores and made red autofluorescences more specific to particular molecules in the cryo-sectioned human livers. Using such fluorescence contrast, we found HCC tissues have reduced levels of 2PAF and longer fluorescence lifetime.
Radicals formed in gamma-irradiated crystals of galactose and glycine were found, upon dissolution, to cause mutagenesis of Salmonella typhimurium strains TA-98 and TA-100. Although the reproducibility of the results has not been adequately determined, they suggest the possibility of developing a test to measure the mutagenic-carcinogenic potential of radiation-induced free radicals with a microbial system.
The effect on an oscillator moving in a medium produced by that part of the radiative force which does not perform work but creates and angular moment is considered. It is shown that the radiative torque turns the dipole toward the axis along which it is moving. Near the axis of motion the dipole executes small oscilltions. The frequency of the oscillations is determined. This effect leads to spontaneous alignment of the dipole moments on moving through the medium. The feasibility of observing the effect experimentally is discussed.
The influence of additionally injected short-wavelength photobleaching light on the radiation hardness of Ge-doped graded index fibers working at 1,300 nm wavelength is investigated. Predictions are complicated by the fact that more efficient shortwave bleaching light experiences higher radiation-induced loss. Promising results are found for low fiber temperatures (approx-lt -50 C) and bleaching light of about 835 nm wavelength.
Radiation hardening and radiation-induced chromium (Cr) depletion were related to intergranular stress corrosion cracking (IGSCC) response among various stainless steels (SS). Available data on neutron-irradiated materials were analyzed and correlations developed between fluence, yield strength, grain-boundary Cr concentration, and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in the critical fluence (0.2 neutrons/cm"2 to 2.5 x 10"2"1 neutrons/cm"2) for IGSCC were documented. Variability often was consistent with yield strength differences among irradiated materials. IGSCC correlated better to yield strength than to fluence for most heats, suggesting a possible role for radiation-induced hardening (and microstructure) on cracking. However, isolated heats revealed a wide range of yield strengths (450 MPa to 800 MPa) necessary to promote IGSCC which could not be explained by strength effects alone. ...
Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.
Epidemiological studies will not solve the shape of the dose effect curve for stochastic effects in the low dose range. Unicellular processes are necessary for the primary processes so that no threshold dose exists. This is evident for somatic and genetic mutations. Not clearly solved is this question for the complex carcinogenesis. These processes develop with manifold interacting molecular and cellular steps. (orig.).
Phospholipid vesicles were found to be lysed by exposure to free radicals derived from irradiated glycine and galactose. The decomposition yield increased with vesicle concentration, and attained values of 0.0006 vesicles destroyed per radical added. Ionic charge at the phospholipid end groups was found to be more important than degree of unsaturation in determining this yield. Radicals derived from irradiated serine and alanine had no detectable lytic action at the vesicle concentrations tested.
Post-irradiation annealing was used to help identify the role of radiation-induced segregation (RIS) in irradiation-assisted stress corrosion cracking (IASCC) by preferentially removing dislocation loop damage from proton-irradiated austenitic stainless steels while leaving the RIS of major and minor alloying elements largely unchanged. The goal of this study is to better understand the underlying mechanisms of IASCC. Simulations of post-irradiation annealing of RIS and dislocation loop microstructure predicted that dislocation loops would be removed preferentially over RIS due to both thermodynamic and kinetic considerations. To verify the simulation predictions, a series of post-irradiation annealing experiments were performed. Both a high purity 304L (HP-304L) and a commercial purity 304 (CP-304) stainless steel alloy were irradiated with 3.2 MeV protons at 360 deg. C to doses of 1.0 and 2.5 dpa. Following irradiation, post-irradiation anneals were performed at ...
Tow experiments were carried out in 1981 and 1982 growth seasons at the greenhouse of the department of agriculture for soils and water researches, atomic energy authority, at inshas, to investigate the responses of two mutation derived lines of sesame and the local cultivar giza 25 to the application of micro nutrients. The possible effect of radiation on germination and growth of sesame seed was also studied in a separate experiment conducted in 1985 season, at inshas.
The three mammalian transforming growth factor (TGF)-β isoforms (TGF-β1, TGF-β2, and TGF-β3) differ in their putative roles in radiation-induced fibrosis in intestine...Full Text Available
Cell death after irradiation occurs by apoptosis in certain cell populations in tissues. The phenomenon also occurs after high linear energy transfer (LET) irradiation, and the relative biological effectiveness (RBE) is 3 to 4 (with respect to low-LET radiation and apoptosis in intestinal crypts) for neutrons with energies of 14 MeV and up to 600 MeV. It is thought that p53 plays a role in the phenomenon, as radiation-induced apoptosis is not observed in p53-null animals. (orig.).
Deer Elk Bighorn Sheep American Pronghorn Moose Deer Mouse Carnivores Bobcat American Badger River Otter Red Fox Long-Tailed Weasel Coyote Grizzly Bear Mountain Lion Amphibians...
Nuclear transfer technology can be applied to produce autologous differentiated cells for therapeutic purposes, a concept termed therapeutic cloning. Countless articles have been published on the ethics...Full Text Available
The extent (density and diameter) of the native (preexisting) collateral circulation in healthy tissues and the capacity of collaterals to enlarge/remodel in obstructive arterial disease are important...Full Text Available
In mammals, primordial germ cells (PGCs) are generated in the extra-embryonic epiblast, and thereafter migrate into the developing gonads. Following the development of the gonads to the testes or ovaries, germ cells mature into sperms or eggs. In the present study, we report production and characterization of monoclonal antibodies (MAb) that recognize PGCs. Extracts from E12.5 mouse embryonic gonads were immunized as an antigen, and hybridomas were generated using the rat medial iliac lymph node method. The hybridoma supernatants were screened by immunohistochemical analyses of E12.5 mouse embryonic sections. The antibody, referred to herein as MAb 5B5, provided strong signals on PGCs. Moreover, immunofluorescence analyses using a variety of the tissue sections of mouse embryos revealed th...
These proceedings collect papers on the subject of lymphokines. Topics include: DNA-cloning of mouse and human lymphokine genes, inteferons, interleukins, gene expression, tumor necrosis factors, and recombinant DNA.
... accidentally released from a Soviet military laboratory (Meselson ... Robert Koch and Louis Pasteur worked to introduce ... species (eg, rat, mouse, dog, monkey) for ...
In a previous study, to identify genes of importance for hepatocellular carcinogenesis, and especially for processes involved in malignant transformation, the authors investigated differences in gene expression between adenomas and carcinomas by DNA microarray. In the present study, the authors investigated AW434047, one of the sequences that was upregulated in carcinomas. The investigation led to the identification of a novel gene, which the authors named hepatocyte malignant transforming factor (HMTF), of unknown function whose expression was increased in hepatocellular carcinomas. Northern blot and in situ hybridization also demonstrated high levels of HMTF in rat hepatocellular carcinoma (HCC) cell lines, lymphocytes in the spleen, colon mucosal epithelia, spermatocytes, and granule cells of the hippocampus. Reduction of HMTF by RNA interference (RNAi) in N1 cells, an HCC cell line, caused suppression of cell ...
Abstract Background & aims: Hepatitis B or C virus infection is considered to be the main cause of hepatocellular carcinoma (HCC) in Japan. Aflatoxin B1 (AFB1) is a carcinogen associated with HCC in regions with high exposure. Mutations in codon 249, exon 7 are a hallmark of AFB1 exposure. Therefore, to clarify the role of AFB1 in hepatocarcinogenesis, we examined AFB1-DNA in liver tissue and sequenced TP53 in Japanese patients with HCC. Methods: Hepatocyte AFB1-DNA adducts were determined immunohistochemically and direct sequencing of TP53 was done to determine mutations in 188 of 279 patients who underwent hepatic resection for HCC. We assessed hepatitis C virus antibodies (HCV Ab) and HBSAg expression; patients without either were defined as having non-B non-C hepatocellular carcinoma (...
The contribution of US, CT and MR imaging was investigated in 25 cirrhotic patients with hepatocellular carcinoma. The following parameters were considered: lesion detection, site and size of the lesion, daughter nodules, location and/or infiltration of intrahepatic vessels, patency of portal vein and collateral vessels, signs of chronic liver disease, steatosis, ascitis, and lymphadenopathy. The results confirm the value of US, which also allowed lesion biopsy in all cases. CT was as accurate as US in detecting the lesion and even superior in demonstranting daughter nodules. MR imaging, with conventional SE and IR sequences, was inferior since it missed 3 lesions due to motion artifacts; more over, a smaller number of daughter nodules was seen than with CT. The authors conclude that, at present, MR imaging cannot replace US and CT; the latter, if combined with artheriography, using either hidrosoluble or liposoluble contrast agents, gives the best results in the ...
In this paper the structural and functional changes of gamma irradiated bovine hemoglobin are presented. Aqueous solutions/1%/of HbO_2 were irradiated in air with doses ranging from 1 to 4 Mrad. Isoelectric focusing indicated change of the charge of irradiated hemoglobin. The isoelectric point of hemoglobin was displaced towards more acid values with increasing doses, up from 1 Mrad. Fingerprint analysis and peptide column chromatography of irradiated hemoglobin demonstrated disturbances increasing with the dose. These changes were confirmed by amino acid analysis which showed that Cys, Met, Trp, His, Pro and Tyr residues were destroyed or modified following irradiation. At doses exceeding 1 Mrad the irradiated solutions of hemoglobin showed a decrease of heme-heme interaction and an increase of affinity for oxygen. Differences observed in oxygen-dissociation curves seem to be correlated with the radiationinduced destruction of amino acid ...
Two local repair procedures, one without (9) and the other with (14) a bulbocavernosus muscle graft were performed on 20 patients with a radiationinduced rectovaginal fistula. Four patients had two procedures successively. The initial success rate of both procedures was 7/9 and 14/14 respectively. Though the initial result of the bulbocavernosus graft was obviously better, in many of the local repair procedures, subclinical radiation damage progressed, resulting in recurrence of rectovaginal fistula (5), rectovesical fistula (4), pararectal abscess (2) etc. After a mean follow up of around 10 years, the success rate of fistula repair decreased to 5/9 and 13/14 and only 2/9 and 6/14 finally remained without a colostomy. A local repair operation should be restricted to carefully selected cases. The musculus gracilis is proposed as a better vascular graft. If the general condition of the patient does not allow more aggressive reconstructive ...
Tensile specimens 60 ..mu..m thick of Ni-8 at. % Si have been bombarded at 475/sup 0/C to doses of 0.1 to 0.3 dpa with either 7 MeV proton or 28 MeV alpha particle beams. Deliberate embrittlement by high temperature (700/sup 0/C) preimplantation of helium was required to produce intergranular fracture. Depth profile sputtering and analysis in a Scanning Auger Microprobe was then used to study radiation-induced segregation of silicon both at the external surfaces and at internal interfaces. The external surfaces exhibited a strongly silicon-enriched zone for the first 10 to 20 nm followed by a broad (approx.200 nm), shallow silicon-depleted region. Segregation of silicon to grain boundaries varied from interface to interface and possibly from region to region on a given interface. In general, however, depth profiles of silicon content with distance from internal boundaries showed no noticeable depletion zone and a more gradual fall-off compared to the profiles from ...
Purpose Radiation-induced heart disease (RIHD) is a severe side effect of thoracic radiotherapy. This study examined the effects of pentoxifylline (PTX) and a-tocopherol on cardiac injury in a rat model of RIHD. Methods and Materials Male Sprague-Dawley rats received fractionated local heart irradiation with a daily dose of 9 Gy for 5 days and were observed for 6 months after irradiation. Rats were treated with a combination of PTX, 100 mg/kg/day, and a-tocopherol (20 IU/kg/day) and received these compounds either from 1 week before until 6 months after irradiation or starting 3 months after irradiation, a time point at which histopathologic changes become apparent in our model of RIHD. Results Radiation-induced increases in left ventricular diastolic pressure (in mm Hg: 35 +- 6 after sham...
This report concerns investigations in the title conducted by 8 groups of National Institute of Radiological Sciences (NIRS) during the period of 1998-2000. The groups are for investigation of: Effects of p53 tumor suppressor gene in radiation-induced leukemia, Role of atm-gene in dose rate effect of ionizing radiation, Function of DNA-dependent protein kinase catalytic subunit (DNA-PK{sub cs}), Functional complementation of radiation-sensitive mutant M10 cell line by human XRCC4 cDNA expression, Role of radiation-induced apoptosis in digital defects in embryonic mice, Functional analysis of S-phase specific novel nuclear protein NP95 by gene targeting, Role of chemokine in T cell development and lymphomagenesis, and establishment of production techniques of gene-modified mice using embryonic stem cells for genetic analysis of radiation-sensitive genes. The groups describe summaries of their studies and published original articles are also ...
Radiation necrosis of normal CNS tissue represents one of the main risk factors of brain irradiation, occurring more frequently and earlier at higher total doses and higher doses per fraction. At present, it is believed that the necrosis results due to increasing capillary permeability caused by cytokine release leading to extracellular edema. This process is sustained by endothelial dysfunction, tissue hypoxia, and subsequent necrosis. Consequently, blocking the vascular endothelial growth factor (VEGF) at an early stage could be an option to reduce the development of radiation necrosis by decreasing the vascular permeability. This might help to reverse the pathological mechanisms, improve the symptoms and prevent further progression. A patient with radiation-induced necrosis was treated with an anti-VEGF antibody (bevacizumab), in whom neurologic signs and symptoms improved in accordance with a decrease in T1-weighted fluid-attenuated inversion recovery signals. ...
Fatty acid esters such as Lipiodol or Ethiodol are known to selectively localize in vascular hepatocellular carcinomas (HCC), following intraarterial hepatic administration. Lipiodol was labeled with radioactive /sup 131/I and administered in 47 patients with HCC for both imaging and therapy. The short term preliminary results suggest radiolabeled Lipiodol is effective in eliminating ascites, shrinking the tumor by a high internal radiation dose, and in improving symptomatology of these tumors. In the future, /sup 90/Y, which is a stronger pure beta-emitter (maximum beta energy of 2.27 MeV, a half life of 64 h, and a maximum penetration or beta range of 11mm), than /sup 131/I will be used for more effective treatment of HCC.
Hepatocellular carcinoma (HCC) is considered to be one of the most common malignancies worldwide, and the most common one in Africa and Asia. Over the last decade, a rising incidence of up to 10-15/100,000 per population has been seen in the Western world, with an estimate of 250,000 deaths and more than a million worldwide per year. By the year 2010, the World Health Organization expects that HCC will be the leading cause of cancer mortality surpassing lung cancer. This increasing incidence is most likely related to an increasing prevalence of chronic hepatitis C (HC) and B (HB) virus infections and other diseases inducing chronic inflammation (Befeler and Di Bisceglie 2002; Llovet et al. 2003).
...comAbstract: Hepatocellular carcinoma (HCC), once thought to be a rare tumor in North America, is a rapidly increasing type of cancer in recent years in the United States. Current treatment modalities to halt the disease progression are only marginally effective. The mainstay treatment ...In addition, NM was shown to down-regulate urokinase plasminogen activator (by fibrin zymography) and up-regulate tissue inhibitors of metalloproteinases (by reverse zymography) in another HCC cell line, Sk-Hep-1. MMP-2 and MMP-9 activities were further modulated by cytokines, inducers and inhibitors, including NM. In ... Our results suggest that NM is an excellent candidate for therapeutic use in the treatment HCC by inhibiting critical parameters in cancer development and progression, such as proliferation, invasion and metastasis, and by inducing apoptosis. Last update: 2 September 2011 JavaScript seems ...
Hepatocellular carcinoma (HCC) represents a major health problem as it afflicts an increasing number of patients worldwide. Albeit most of the risk factors for HCC are known, this is a deadly syndrome with a life expectancy at the time of diagnosis of less than 1?year. Definition of the molecular principles governing the neoplastic transformation of the liver is an urgent need to facilitate the clinical management of patients, based on innovative methods to detect the disease in its early stages and on more efficient therapies. In the present study, we have combined the analysis of a murine model and human samples of HCC to identify genes differentially expressed early in the process of hepatocarcinogenesis, using a microarray-based approach. Expression of 190 genes was impaired in murine ...
The thermal properties of five types of radiation-induced wood-polymer composites based on a tropical hardwood, rubberwood (Hevea braziliensis), was studied by oxygen index measurement, differential thermal analysis (DTA) and thermogravimetry (TG). The DTA and TG curves of composites were different from those of rubberwood, which can be attributed to the presence of the incorporated polymers. Of the five composites, the one impregnated with bis(2-chloroethyl)vinyl phosphonate reduced the initial temperature of decomposition, increased the peak temperatures of exothermic reactions, and increased the char yield. Comparison with physical blends of rubberwood and the corresponding polymer provided some evidence of chemical interaction of wood and polymer in some of the composites. (author).
This is a preliminary study on the sound absorption properties of two tropical hardwoods, Light Red Meranti and Ramin, and their wood-polymer composites. Sound absorption is measured using a standing wave apparatus. The samples are of one thickness (7 mm) and cut longitudinally. Wood-polymer composites are made by impregnating the samples with methyl methacrylate which is polymerized in situ through #gamma#-irradiation. Both woods and their composites are better sound absorbers at higher sound frequencies. With partial impregnation, the absorption coefficients are improved upon particularly in the region between 1-3 kHz. (author).
In future experiments the readout electronics for pixel detectors is required to be resistant to a very high radiation level. In this paper we report on irradiation tests performed on several preFPIX2 prototype pixel readout chips for the BTeV experiment exposed to a 200 MeV proton beam. The prototype chips have been implemented in commercial 0.25 {micro}m CMOS processes following radiation tolerant design rules. The results show that this ASIC design tolerates a large total radiation dose, and that radiationinduced Single Event Effects occur at a manageable level.
Polymerizing effects of high energy radiation has been found suitable for preparation of wood-polymer composites. In the present work after evaluating polymer products that have been obtained by irradiation method, wood-polymer composites have been prepared by in situ polymerization of vinyl acetate, acrylic acid and acrylic acid/styrene mixture using two samples of Iranian hardwoods, Beech and Hornbeam. These woods and their composites have been tested for their physical and mechanical properties. The results have shown that chemical bonding between polymer and the cell wall component lead to better strength properties in the composites. (author).
A wood/polymer composite was produced by impregnating Ramin wood with methyl methacrylate monomer and subsequently polymerizing it by gamma irradiation. To assess the improvement in compression strength of the wood caused by the polymer impregnation, a microbuckling compression failure mechanism was used to model the compression failure of the composite. Such a mechanism was found to predict a linear relationship between the compression strength and the percentage polymer impregnation (by weight). Uniaxial compression test results at 45({plus minus}5)% and 90({plus minus}5)% relative humidity levels, after being statistically analysed, showed that such a linear relationship was valid for up to 100% polymer impregnation. (author).
A wood/polymer composite was produced by impregnating Ramin wood with methyl methacrylate monomer and subsequently polymerizing it by gamma irradiation. To assess the improvement in compression strength of the wood caused by the polymer impregnation, a microbuckling compression failure mechanism was used to model the compression failure of the composite. Such a mechanism was found to predict a linear relationship between the compression strength and the percentage polymer impregnation (by weight). Uniaxial compression test results at 45(#+-#5)% and 90(#+-#5)% relative humidity levels, after being statistically analysed, showed that such a linear relationship was valid for up to 100% polymer impregnation. (author).
Wood-plastic composites (WPC) have been prepared with five low-grade woods, native to Syria, using three monomer systems; acrylamide, butylmethacrylate, and styrene, with methanol as the swelling solvent. Polymerization was induced at various radiation doses (10, 20, and 30 kGy) at a dose rate of 3.5 kGy/h using a {sup 60}Co gamma radiation source. Some physical properties of WPC, namely polymer loading and compression strength have been measured. The polymer loading decreases approximately with increasing density of the wood species used.
Wood-plastic composites (WPC) have been prepared with five low-grade woods, native to Syria, using three monomer systems; acrylamide, butylmethacrylate, and styrene, with methanol as the swelling solvent. Polymerization was induced at various radiation doses (10, 20, and 30 kGy) at a dose rate of 3.5 kGy/h using a "6"0Co gamma radiation source. Some physical properties of WPC, namely polymer loading and compression strength have been measured. The polymer loading decreases approximately with increasing density of the wood species used.
Wood-plastic composites (WPC) have been prepared with five low-grade woods, native to Syria, using three monomer systems; acrylamide, butylmethacrylate, and styrene, with methanol as the swelling solvent. Polymerization was induced at various radiation doses (10, 20, and 30 kGy) at a dose rate of 3.5 kGy/h using a "6"0Co gamma radiation source. Some physical properties of WPC, namely polymer loading and compression strength have been measured. The polymer loading decreases approximately with increasing density of the wood species used. (author)
Spectra of e.p.r. radicals in cellulose and timber gamma-irradiated at 77 and 300 K have been measured. Radiation yields and the kinetics of radicals accumulation have been studied. The effect of ionizing radiation on cellulose is the appearance of radicals resulting from rupture of C-H bonds in positions 1 and 4. Timber, additionally, forms ''lignin'' radicals. A mechanism of cellulose and timber radiolysis is suggested. ''Lignin''-type compounds present in timber protect polysaccharides from radiation-induced destruction.
This short survey focuses on the main radiation-induced base lesions that have been identified within cellular DNA. For this purpose, sensitive assays that are aimed at measuring a few modifications per 10{sup 7} normal bases were set-up. In that respect high performance liquid chromatography - tandem mass spectrometry (CLHP-MS/MS) was found to be able to single out the formation of 9 oxidized nucleosides and two modified nucleo-bases out of the 70 oxidative base lesions that have been identified in model systems. As a striking result, it was found that in the DNA of {gamma}-irradiated human monocytes, the formamide-pyrimidine derivative of guanine is produced in a higher yield than the ubiquitous 8-oxo-7,8-dihydro-guanine damage, both arising from the same radical precursor. However, relatively high doses of ionizing radiation (> 20 Gy) have to be applied in order to detect an increase in the level of the damage. This is due to the low efficiency for both ...
Radiation-induced enteritis is a well-recognized sequel of therapeutic irradiation. Therefore we examined the radioprotective properties of Punica granatum peel extract (PPE) on the oxidative damage in the ileum. Rats were exposed to a single whole-body X-ray irradiation of 800 cGy. Irradiated rats were pretreated orally with saline or PPE (50 mg/kg/day) for 10 days before irradiation and the following 10 days, while control rats received saline or PPE but no irradiation. Then plasma and ileum samples were obtained. Irradiation caused a decrease in glutathione and total antioxidant capacity, which was accompanied by increases in malondialdehyde levels, myeloperoxidase activity, collagen content of the tissue with a concomitant increase 8-hydroxy-2'-deoxyguanosine (an index of oxidative DNA damage). Similarly, pro-inflammatory cytokines (TNF-?, IL-1? and IL-6) and lactate dehydrogenase were elevated in irradiated groups as compared to control. PPE treatment reversed ...
This paper explores for the first time the post-radiation-induced-graft polymerization on solid substrate using reversible addition-fragmentation transfer (RAFT) mechanism. Radiation-induced graft polymerization onto polymers is a potentially interesting technique to create easily new materials from highly resistant polymers, e.g. surface graft polymerization of acrylic acid (AA) onto poly(vinylidene difluoride) (PVDF) improves its surface properties without losing its excellent mechanical properties. As a consequence of the radical nature of the polymerization processes it is difficult to control molecular weight of grafted chains, and therefore design and standardize the properties of the final product. RAFT polymerization is a suitable method to obtain monodisperse polymers. The ability of the RAFT agents to control the polymer chain length could be an interesting approach to improve the grafted polymers obtained by ...
Full text: DNA rearrangement events leading to chromosomal aberrations are central to ionizing radiation-induced cell death. Although DNA double-strand breaks are probably the lesion that initiates formation of chromosomal aberrations, little is understood about the molecular mechanisms that generate and modulate DNA rearrangement. Examination of the sequences that flank sites of DNA rearrangement may provide information regarding the processes and enzymes involved in rearrangement events. Accordingly, we developed a method using inverse PCR that allows the detection and sequencing of putative radiation-induced DNA rearrangements in defined regions of the human genome. The method can detect single copies of a rearrangement event that has occurred in a particular region of the genome and, therefore, DNA rearrangement detection does not require survival and continued multiplication of the affected cell. Ionizing ...
Apoptosis, or programmed cell death (PCD), is a fundamental process that protects organismal integrity. In earlier work, we demonstrated that over-expression of either of two anti-apoptotic members of the BCL-2 family (BCL-2 or BCL-X L could elevate the frequency of radiation-induced mutations at the autosomal TK1 locus in human TK6 lymphoblasts that express wild-type TP53. Ectopic expression of BCL-X L also elevated the frequencies of double-strand break-induced gene conversion. The purpose of this study is to determine if BCL-2 family proteins promote radiation mutagenesis indirectly through their suppression of PCD, or whether the 'pro-mutagenic' function of these proteins can be separated from their anti-apoptotic function. We developed stable transfectants of TK6 cells that express a mutated form of BCL-X L with a single amino acid substitution in the BH1 domain that is known to interfere with the ability to suppress PCD (BCL-X L gly159ala). We also developed ...
Two monoclonal antibodies, TAL-1B5 and TAL-3C3, specific for human Ia alpha-chain subunits have been produced by fusing P3/NSI/1-Ag4-1 mouse myeloma cells with spleen cells from a BALB/c mouse immunized...Full Text Available
Genome sequences are essential tools for comparative and mutational analyses. Here we present the short read sequence of mouse chromosome 17 from the Mus musculus domesticus derived...Full Text Available
Cadmium (Cd) exposure causes glucosuria (glucose in the urine). Previously, it was shown that Cd exposure of primary cultures of mouse kidney cells (PMKC) decreased mRNA levels of the glucose...Full Text Available
PurposeTo characterize differences in retinal ganglion cell (RGC) function in mouse strains relevant to disease models. C57BL/6J (B6) and DBA/2J (D2) are the two most common mouse...Full Text Available
The human smooth muscle myosin heavy chain locus (MYH11) was mapped by fluorescence in situ hybridization to the middle of the p arm of chromosome 16 using a genomic cosmid clone containing coding sequences of the gene as probe. Probe from coding sequence, when applied to Southern blots of a panel of hybrids containing different portions of human chromosome 16, localized the gene to 16p13.13-13.12. Coding sequence PCR primers, when used on the DNA from a CHO-mouse hybrid clone mapping panel informative for mouse chromosomes, showed that the gene was located on mouse chromosome 16. These results correct a recent assignment of MYH11 from 16q12.2 to the region of the 16p-arm inversion breakpoint seen in acute myelomonocytic leukemia (AMML) M4Eo and demonstrate that the conflicting data do not result from the presence of additional MYH genes on the q arm of the chromosome. Also, a new region of conserved synteny between human ...
The loss of #alpha#-globin gene transcriptional activity rarely occurs as an acquired abnormality during the evolution of myeloproliferative disease or preleukemia. To test whether the mutation responsible for the loss of #alpha#-globin gene expression (hemoglobin H disease) in these patients is linked with the #alpha#-globin genes on chromosome 16, the authors transferred chromosome 16 from preleukemic patients with acquired hemoglobin H disease to mouse erythroleukemia cells and measured the transcriptional activity of the human #alpha#-globin genes. After transfer to mouse erythroleukemia cells, the expression of human #alpha#-globin genes from the peripheral blood or marrow cells of preleukemic patients with acquired hemoglobin H disease was similar to that of human #alpha#-globin genes transferred to mouse erythroleukemia cells from normal donors. These data showed that factor(s) in the mouse ...
More data about TACE and pTACE seem necessary to better define the global treatment strategy for HCC. Aim of our analysis was to evaluate the role of TACE, either with lipiodol (traditional) or drug-eluting...Full Text Available
Two integrated hepatitis B virus (HBV) DNA molecules were cloned from two primary hepatocellular carcinomas each containing only a single integration. One integration (C3) contained a single linear...Full Text Available
BackgroundHepatitis C virus (HCV) infection is the leading cause of chronic hepatitis which progresses to hepatocellular carcinoma (HCC) afflicting > 170 million people worldwide....Full Text Available
Apoptosis and Proliferation During DicWoroacetic Acid (DCA) Induced Hepatocellular Carcinogenesis in the F344 Male Rat Chlorine, introduced into public drinking \\\\'ater supplies for disinfection, can react with organic compounds in surface waters to form toxic by-prod...
Maintenance of genomic integrity in embryonic cells is pivotal to proper embryogenesis, organogenesis and to the continuity of species. Cultured mouse embryonic stem cells (mESCs), a model for early embryonic cells, differ from cultured somatic cells in their capacity to remodel chromatin, in their repertoire of DNA repair enzymes, and in the regulation of cell cycle checkpoints. Using 129XC3HF1 mESCs heterozygous for Aprt, we characterized loss of Aprt heterozygosity after exposure to ionizing radiation. We report here that the frequency of loss of heterozygosity mutants in mESCs can be induced several hundred-fold by exposure to 5-10Gy of X-rays. This induction is 50-100-fold higher than the induction reported for mouse adult or embryonic fibroblasts. The primary mechanism underlying the...
Abstract Crouzon syndrome is characterized by premature fusion of sutures and synchondroses. Recently, the first mouse model of the syndrome was generated, having the mutation Cys342Tyr in Fgfr2c, equivalent to the most common human Crouzon/Pfeiffer syndrome mutation. In this study, a set of micro-computed tomography (CT) scannings of the skulls of wild-type mice and Crouzon mice were analysed with respect to the dysmorphology caused by Crouzon syndrome. A computational craniofacial atlas was built automatically from the set of wild-type mouse micro-CT volumes using (1) affine and (2) non-rigid image registration. Subsequently, the atlas was deformed to match each subject from the two groups of mice. The accuracy of these registrations was measured by a comparison of manually placed landma...
Virtually all biomedical research makes use of a relatively small pool of laboratory-adapted, inbred, isogenic stocks of mice. Although the advantages of these models are many, there are a number of...Full Text Available
Significant emphasis has recently been placed on the characterization of the human cancer genome. This effort has been assisted by the development of new DNA sequencing technologies that allow...Full Text Available
Dominant mutations in sarcomere protein genes cause hypertrophic cardiomyopathy, an inherited human disorder with increased ventricular wall thickness, myocyte hypertrophy, and disarray. To understand...Full Text Available
The role of IGF-I in the negative regulation of GH expression and release is demonstrated by in vitro and in vivo models; however, the targets and mechanisms of IGF-I...Full Text Available
Advances in laboratory animal imaging have provided new resources for noninvasive biomedical research. Among these technologies is microcomputed tomography (microCT) which is widely used to obtain high...Full Text Available
BackgroundXenotropic Murine Leukemia Virus-related (XMRV) virus is a recently identified mouse gammaretrovirus that has the ability to infect certain human cells. In this study,...Full Text Available
As part of a combined study of the responses of the mouse adrenal gland and kidney to X-irradiation, the weight of adrenal glands, the relative volumes of the cortex and medulla and the aldosterone output were measured at predetermined times after irradiation of the left organs only.
Taste cells use multiple signaling mechanisms to generate appropriate cellular responses to discrete taste stimuli. Some taste stimuli activate G protein coupled receptors (GPCRs) that cause calcium...Full Text Available
This unit presents two basic protocols that offer rapid assessments of anosmia (the absence of a sense of smell) in mice. The buried food test is used to check for the ability to smell volatile...Full Text Available
The effects of muscarinic agonists and diisopropylfluorophosphate (DFP) on muscarinic receptor density and muscarinic receptor-mediated responses was assessed in mouse brain and mouse neuroblastoma cells (clone N1E-115). Utilizing the antagonist ({sup 3}H)quinuclidinyl benzilate (({sup 3}H)QNB), there was no difference in the maximal binding capacity (B{sub max}) or equilibrium dissociation constant (K{sub d}) between untreated and 24 hour DFP-treated mice. However, one administration of DFP produced a 24% and 33% decrease in B{sub max} measured by ({sup 3}H)N-methylscopolamine (({sup 3}H)NMS) after 18 and 24 hours which was rapidly reversible within 36 hours after DFP treatment. The loss of ({sup 3}H)NMS binding sites following acute DFP treatment was not accompanied by a change in a particular muscarinic receptor binding conformation. Furthermore, the magnitude of muscarinic receptor-mediated phosphoinositide hydrolysis was unchanged ...
AbstractStudies performed to identify early events of ovarian cancer and to establish molecular markers to support early detection and development of chemopreventive regimens have been...Full Text Available
... from Dr. Austin Smith of the Institute for Stem Cell Research, University of Edinburgh) was modified from the CGR8 ... to thank Dr. Austin Smith, the Institute for Stem Cell Research, University of Edinbu...
Genomic disorders are conditions that result from DNA rearrangements, such as deletions or duplications. The identification of the dosage-sensitive gene(s) within the rearranged genomic interval is...Full Text Available
The activity of mice in their home cage is influenced greatly by the cycle of light and dark. In addition, home-cage activity shows remarkable time-dependent changes that result in a prominent temporal...Full Text Available
We have studied the functions of the intracellular RNAs of mouse mammary tumor virus (MMTV) by purification and translation in vitro. Two major size classes of MMTV RNA, 35S and 24S RNA, were isolated...Full Text Available
Trichloroethylene (TCE) is both acutely toxic and carcinogenic to the mouse lung following exposure by inhalation. In contrast, it is not carcinogenic in the rat lung and is markedly less toxic following...Full Text Available
Recent reports suggested that phosphatase of regenerating liver (PRL)-3 might be involved in colorectal carcinoma metastasis with an unknown mechanism. Here we demonstrated that PRL-3 expression was...Full Text Available
Idiopathic pulmonary fibrosis (IPF) is a progressive disease with poor survival. The identification of therapeutic targets is essential to improving outcomes. Previous studies found that expression...Full Text Available
BackgroundSeasonal influenza A infection affects a significant cohort of the global population annually, resulting in considerable morbidity and mortality. Therapeutic strategies...Full Text Available
Mouse models for the study of autistic-like behaviors are increasingly needed to test hypotheses about the causes of autism, and to evaluate potential treatments. Both the automated 3-chambered...Full Text Available
Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome type B) is a metabolic disorder with devastating clinical characteristics starting in early childhood and leading to premature death. A...Full Text Available
Vulnerability to abused drugs is influenced by multiple genes unique to each drug as well as to risk genes for polydrug abuse. If several inbred mouse strains respond to different drugs similarly,...Full Text Available
The integration sites for viral DNA in cells infected with Moloney murine leukemia virus (M-MuLV) were studied by restriction endonuclease cleavage of cellular DNA followed by electrophoresis in agarose...Full Text Available
PurposeThe size of neuronal populations is modulated by gene variants that influence cell production and survival, in turn influencing neuronal connectivity, function,...Full Text Available
Background:Nicotine alters auditory event-related potentials (ERPs) in rodents and humans and is an effective treatment for smoking cessation. Less is known about the effects of...Full Text Available
Early detection of precancerous tissue has significantly improved survival of most cancers including colorectal cancer (CRC). Animal models designed to study the early stages of cancer are valuable...Full Text Available
The formation of mammalian secondary palate requires a series of developmental events such as growth, elevation and fusion. Despite recent advances in the field of palate development, the process...Full Text Available
BackgroundMacrophages (MΦs) utilize macropinocytosis to integrate immune and metabolic signals in order to initiate an effective immune response. Diabetes is characterized...Full Text Available
The effect of Photofrin-based photodynamic therapy (PDT) and adjuvant treatment with serum vitamin D3-binding protein-derived macrophage-activating factor (DBPMAF) was examined using a mouse SCCVII...Full Text Available
Purpose: Small animal micro-CT imaging is being used increasingly in preclinical biomedical research to provide phenotypic descriptions of genomic models. Most of this imaging is coincident...Full Text Available
In addition to its role in megakaryocyte production, signaling initiated by thrombopoietin (TPO) activation of its receptor, myeloproliferative leukemia virus protooncogene (c-Mpl, or Mpl), controls...Full Text Available
BackgroundApolipoprotein E (ApoE), a cholesterol carrier associated with atherosclerosis, is a major risk factor for Alzheimer's disease (AD). The low-density lipoprotein receptor...Full Text Available
The AKR mouse strain is characterized by a high incidence of spontaneous thymic lymphoma that appears in older animals (greater than 6 months of age) and is associated with novel provirus integrations...Full Text Available
There is increasing consensus that the uterotrophic estrogenicity assay should be coupled with other morphometric or molecular end points that might enhance its sensitivity. We have previously shown...Full Text Available
Insulin resistance in skeletal muscle is a key phenotype associated with type 2 diabetes (T2D) for which the molecular mediators remain unclear. We therefore conducted an expression analysis of human...Full Text Available
Mouse models have dramatically improved our understanding of cancer development and tumor biology. However, these models have shown limited efficacy as tractable systems for unbiased genetic...Full Text Available
Using a syngeneic p53-null mouse mammary gland tumor model that closely mimics human breast cancer, we have identified, by limiting dilution transplantation and in vitro mammosphere assay, a Lin(-)CD29(H)CD24(H) subpopulation of tumor-initiating cells. Upon subsequent transplantation, this subpopulation generated heterogeneous tumors that displayed properties similar to the primary tumor. Analysis of biomarkers suggests the Lin(-)CD29(H)CD24(H) subpopulation may have arisen from a bipotent mammary progenitor. Differentially expressed genes in the Lin(-)CD29(H)CD24(H) mouse mammary gland tumor-initiating cell population include those involved in DNA damage response and repair, as well as genes involved in epigenetic regulation previously shown to be critical for stem cell self-renewal. These studies provide in vitro and in vivo data that support the cancer stem cell (CSC) hypothesis. Furthermore, this p53-null mouse mammary ...
BackgroundThe zinc-finger transcription factor GLI3 is an important mediator of Sonic hedgehog signaling and crucial for patterning of many aspects of the vertebrate body plan. In...Full Text Available
BackgroundDue to the high morbidity and mortality of fulminant hepatitis, early diagnosis followed by early effective treatment is the key for prognosis improvement. So far, little...Full Text Available
BackgroundRecessive mutations in guanylate cyclase-1 (Gucy2d) are associated with severe, early onset Leber congenital amaurosis-1(LCA1). Gucy2d...Full Text Available
Fibroblast cell population kinetics in the developing molar periodontal ligament was investigated in 10, 12, 16 and 20 days old mice by autoradiography after the administration of [3H]thymidine. Labelled...Full Text Available
BackgroundNon-small cell lung cancer (NSCLC) is the foremost cause of cancer-related death in Western countries, which is due partly to the propensity of NSCLC cells to metastasize....Full Text Available
BackgroundBrevican is a member of the lectican family of aggregating extracellular matrix (ECM) proteoglycans that bear chondroitin sulfate (CS) chains. It is highly expressed in...Full Text Available
In the present study we have used the alkaline elution technique to study the effect of misonidazole (MISO) on the initial amount of DNA cross-linking in various normal and neoplastic tissues of C3H...Full Text Available
During asymmetric mitosis, both in male Drosophila germline stem cells and in mouse embryo neural progenitors, the mother centrosome is retained by the self-renewed cell; hence suggesting...Full Text Available
BackgroundDiurnal fluctuation of bile acid (BA) concentrations in the enterohepatic system of mammals has been known for a long time. Recently, BAs have been recognized as signaling...Full Text Available
While pleiotropic adaptive mutations are thought to be central for evolution, little is known on the downstream molecular effects allowing adaptation to complex ecologically relevant environments. Here...Full Text Available
Oocyte-cumulus cell bidirectional communication is essential for normal development of the oocyte and cumulus cells (CCs) within the follicle. We showed recently that addition of recombinant growth...Full Text Available
NG2 chondroitin sulfate proteoglycan is a surface marker of oligodendroglial progenitor cells (OPCs) in various species. In contrast to well-studied rat OPCs, however, we found that purified...Full Text Available
A novel therapeutic compound was found to induce bladder tumors in male rats. Given the location of the tumors and the increased amounts of calcium- and magnesium-containing solids found in the urine...Full Text Available
Uncoupling protein 2 (UCP2) maps to a region on distal mouse chromosome 7 that has been linked to the phenotypes of obesity and type II diabetes. We recently reported that UCP2 expression is increased...Full Text Available
A tk{sup +/-} mouse embryonic stem (ES) cell line, designated 1G2, has been created in which one allele of the thymidine kinase (tk) gene was inactivated by targeted homologous recombination. This line is an analog of the mouse lymphoma tk{sup +/-} L5178Y cell line, which is used widely to assess the mutagenicity of chemical agents. Treatment of 1G2 cells with the alkylating agent N-ethyl-N-nitrosourea (ENU) resulted in a dose-related increase in tribluorothymidine-resistant colonies. Mutant frequencies of 152 and 296 per 10{sup 6} cells were determined for 0.1 and 0.3 mg/ml doses of ENU, compared with a spontaneous mutant frequency of 15 per 10{sup 6} cells. The data indicate that tk{sup +/-} 1G2 ES cells may be useful for the creation of a transgenic mouse model for assessing in vivo mutation using an endogenous autosomal gene. 45 refs., 2 figs., 1 tab.
OBJECTIVEPrevious studies showed that genetic deletion or pharmacological blockade of the receptor for advanced glycation end products (RAGE) prevents the early structural changes...Full Text Available
Spontaneous mouse models of cancer show promise to more accurately recapitulate human disease and predict clinical efficacy. Transgenic mice or viral vectors have been required to generate spontaneous...Full Text Available
Changes in the number of chromosomes, but also variations in the copy number of chromosomal regions have been described in various pathological conditions, such as cancer and aneuploidy, but also in...Full Text Available
Self-renewal of spermatogonial stem cells (SSCs) is the foundation for maintenance of spermatogenesis throughout life in males and for continuation of a species. The molecular mechanism underlying stem...Full Text Available
BackgroundMammalian antimicrobial peptides (AMPs) are effectors of the innate immune response. A multitude of signals coming from pathways of mammalian pathogen/pattern recognition...Full Text Available
Mice were killed 7, 11, 19, and 27 weeks after infection with strains of Schistosoma mansoni from Puerto Rico, Brazil, St Lucia, and Tanzania. The percentage recovery of adult worms...Full Text Available
We report the isolation of cDNA clones for the mouse {alpha}7 neuronal nicotinic acetylcholine receptor subunit (gene symbol Acra7), the only nicotinic receptor subunit known to bind a-bungarotoxin in mammalian brain. This gene may have relevance to nicotine sensitivity and to some electrophysiologic findings in schizophrenia. The mouse {alpha}7 subunit gene encodes a protein of 502 amino acids with substantial identity to the rat (99.6%), human (92.8%), and chicken (87.5%) amino acid sequences. The {alpha}7 gene was mapped to mouse chromosome 7 near the p locus with the following gene order from proximal to distal: Myod1-3.5 {+-}1.7 cM-Gas2-0.9 cM {+-} 0.9 cM-D7Mit70-1.8 {+-} 1.2 cM- Acra7-4.4 {+-}1.0 cM-Hras1-ps11/Igf1r/Snrp2a. The human gene was confirmed to map to the homologous region of human chromosome 15q13-q14. 26 refs., 3 figs.
During blastocyst formation the segregation of the inner cell mass (ICM) and trophectoderm is governed by the mutually antagonistic effects of the transcription factors Oct4 and Cdx2. Evidence indicates...Full Text Available
We sought to determine the effects of activation of peroxisome proliferator-activated receptor-γ (PPAR-γ) on multilocularization of adipocytes in adult white adipose tissue (WAT). Male...Full Text Available
BackgroundA fundamental requirement for the exploitation of embryonic stem (ES) cells in regenerative medicine is the ability to reproducibly derive sufficient numbers of cells of...Full Text Available
Cultured mouse or human embryonic stem (ES) cells provide access to all of the genes required to elaborate the fundamental components and physiological systems of a mammalian cell. Chemical or insertional...Full Text Available
BackgroundStorage of RBCs is necessary for an adequate blood supply. However, reports have identified potential negative sequelae of transfusing stored RBCs. An animal...Full Text Available
SUMMARYAmeloblastin (AMBN) is the second most abundant extracellular matrix protein produced by the epithelial cells called ameloblasts and is found mainly in forming dental enamel....Full Text Available
Large-scale cancer genome projects will soon be able to sequence many cancer genomes to comprehensively identify genetic changes in human cancer. Genome-wide association studies have also identified...Full Text Available
Radiationinduced polymerization of methylmethacrylate and copolymerization of styrene-acrylonitrile mixture in mamrase Carpinus betulus was carried out by means of #gamma#-ray, under different moisture levels and additives. Under all conditions the degree of polymerization was as high as 60%. No pronounced differences were observed in the kinetics of the polymerization of MMA either with moisture content of wood nor with kind and amount of additives. At high moisture (80% RH) content the dimensional stability of wood-PMMA was increased four fold as compared with untreated wood. The hardness increased about 100% for a weight conversion of monomer of about 30 to 40%. Hardness of this wood-polymer composite is comparable to that of the best noble woods in the world. (author).
Most plans for the disposition of surplus nuclear materials involve storage in sealed containers where the evolution of gases from reactions of adsorbed water could present both pressure and flammability hazards[l] . Despite efforts such as calcining the material to minimize the water content prior to packaging, both residual moisture and readsorbed water may be present in the final containers . Given the anticipated temperature excursions during transportation and storage, this water may thermally desorb, increasing the pressure, and/or thermally dissociate to produce H2 gas, increasing flammability hazards . In addition, the radiation from the nuclear material may induce radiolysis of the water with the likely products being water vapor, H2, 02 and H2O2. In order to better understand the relative importance of the thermal- and radiationinduced chemistry, we have studied the interactions of water on single crystals of uranium dioxide .
The process of radiationinduced electron capture by protons or deuterons producing new ultra low momentum neutrons and neutrinos may be theoretically described within the standard field theoretical model of electroweak interactions. For protons or deuterons in the neighborhoods of surfaces of condensed matter metallic hydride cathodes, such conversions are determined in part by the collective plasma modes of the participating charged particles, e.g. electrons and protons. The radiation energy required for such low energy nuclear reactions may be supplied by the applied voltage required to push a strong charged current across a metallic hydride surface employed as a cathode within a chemical cell. The electroweak rates of the resulting ultra low momentum neutron production are computed from these considerations.
Elevation of zinc protoporphyrin (ZPP) levels in the blood has served as an indicator of lead poisoning and iron deficiency anemia for many years. We have discovered that sublethal doses of whole body irradiation with x-rays also elevates ZPP 2-3-fold over normal levels. The ZPP level does not begin to increase until days 12-14 postirradiation and peaks between days 18 and 20 before returning to normal levels between days 28 and 35. Increasing the radiation dose delays the onset of the rise in ZPP, but does not affect the magnitude of the elevation. At lethal doses, ZPP elevation is not observed. Neither of the two previously described mechanisms that cause elevations of ZPP, namely iron deficiency and inhibition of ferrochelatase, are responsible for the radiation-induced elevation of ZPP. The elevation of ZPP appears to be correlated with the recovery of the hematopoietic system from radiation injury.
Irradiation of EP-823 (16Cr12MoWsiVNbB) ferritic-martensitic steel with 7-MeV Ni++ ions and with 30- and 70-keV He+ ions at a temperature of 500?C was followed by an increase in the microhardness, which was due to both radiation point defects and changes in the phase composition and the dislocation structure of the steel. It was found that the dependence of the largest relative increase in the microhardness on the concentration of radiation-induced point defects in the near-surface region of the steel under irradiation with different ions correlated with an analogous dependence of the surface segregation of silicon and chromium.
The synthetic process of polyethylene cation exchange capillary via radiation grafting polystyrene by simultaneous irradiation with "6"0Co #gamma#-ray source and sulfonation with concentrated H_2SO_4 was studied. The effects of dose, dose rate, monomer concentration, solvents, temperature and crosslinking agents on the graft copolymerization of styrene with polyethylene capillary were illustrated. The relationship between the radiation grafting conditions and the properties of ion-exchange capillary were examined. A polyethylene cation exchange capillary with I.D. 0.8 mm, length 20 m, exchange capacity 0.7 Meq/g 60% capacity in 10 s (flow rate 20 ml/min) was prepared. No significant loss of copacity was found from this ion-exchange capillary after 200 adsorption/regeneration cycles.
We study CP-violating phenomena in the production, mixing and decay of a coupled system of CP-violating neutral Higgs bosons at {gamma}{gamma} colliders, assuming a Minimal Supersymmetric Standard Model (MSSM) Higgs sector in which CP violation is radiativelyinduced by phases in the soft supersymmetry-breaking gaugino masses and third-generation trilinear squark couplings. We discuss CP asymmetries in the production and decays of {mu}{sup +}{mu}{sup -}, {tau}{sup +}{tau}{sup -}, b-bar b and t-bar t pairs. We find large asymmetries when two (or all three) neutral Higgs bosons are nearly degenerate with mass differences comparable to their decay widths, as happens naturally in the CP-violating MSSM for values of tan{beta}-bar 5 (30) and large (small) charged Higgs-boson masses.
We study CP-violating phenomena in the production, mixing and decay of a coupled system of CP-violating neutral Higgs bosons at #gamma##gamma# colliders, assuming a Minimal Supersymmetric Standard Model (MSSM) Higgs sector in which CP violation is radiativelyinduced by phases in the soft supersymmetry-breaking gaugino masses and third-generation trilinear squark couplings. We discuss CP asymmetries in the production and decays of #mu#"+#mu#"-, #tau#"+#tau#"-, b-bar b and t-bar t pairs. We find large asymmetries when two (or all three) neutral Higgs bosons are nearly degenerate with mass differences comparable to their decay widths, as happens naturally in the CP-violating MSSM for values of tan#beta#-bar 5 (30) and large (small) charged Higgs-boson masses.
Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features of these two cases ...
Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features of these two cases ...
The first part of the study contains a literature compilation of more than 50 original publications reporting the radiationinduced effects in 17 different high polymer materials and glass which are relevant in the manufacturing of medical devices or packing materials. The results collected demonstrate that high energy radiation, i.e. gamma- or X-rays, causes various physical and chemical alterations in high polymer materials. A detailed summary and discussion of the results of the original publications is not included in the present report, it will be presented in the second part of the study. Furthermore, the second part of the study will refer to the aspect of wholesomeness of irradiated medical devices or packing materials in a more general manner of representation. (orig.).
Photoluminescence spectroscopy measurements were carried out for silicon 50{mu}m BSFR space solar cells irradiated with 1MeV electrons with a fluence exceeding 1 x 10{sup 16} e/cm{sup 2} and 10MeV protons with a fluence exceeding 1 x 10{sup 13} p/cm{sup 2}. The results were compared with the previous result performed in a relative low fluence region, and the radiation-induced defects which cause anomalous degradation of the cell performance in such large fluence regions were discussed. As far as we know, this is the first report which presents the PL measurement results at 4.2K of the large fluence radiation irradiated silicon solar cells. (author)
Electrodynamic properties of processes involving charged tachyons are considered in connection with the real superluminal Lorentz transformations. These transformations are interpreted without making use of a tachon corridor and so that the interaction of tachyons from subluminal sources with ordinary matter is Lorentz invariant. Transformations of the electromagnetic fields are deduced from the extended principle of relativity. They are necessary in order to obtain the field equations that are satisfied by fields obeying Maxwell equations relative to superluminal inertial frames with respect to subluminal inertial frames. The field equations allow one to get the dependence of the field energy density and its current on the field strengths. The resulting equations are applied in a discussion of plane electromegnetic waves, sent out by a superluminal source. The obtained electrodynamics allows the existence of charged tatric charges do not behave as magnetic monopoles. At last the ...
Nickel ion radiation at 500 C was shown to have a strong effect on the surface electrochemistry and intergranular corrosion (IGC) of stainless steel (SS). Measured current densities in a 1 N sulfuric acid solution at room temperature were increased at active-passive, passive, and transpassive potentials. Radiation effects on the current decay behavior and susecptibility to IGC were similar for a fine-grained (FG) S alloy and for a very large-grained (LG) SS. Radiation-induced segregation (RIS) at the surface was believed to promote higher currents at short times, whereas segregation at grain boundaries was responsible for IG attack. Analytical electron microscopy (AEM) measurements revealed chromium and iron depletion plus Ni and silicon enrichment at grain boundaries in irradiated specimens. Si enhanced dissolution at transpassive potentials, whereas Cr depletion did the same at active-passive and passive potentials.
Counting characteristics of X-ray detectors fabricated from indium-doped, gallium-doped, and chlorine-doped CdTe have been investigated. The detectors fabricated from indium-doped and gallium-doped crystals showed radiation-induced polarization, namely, a progressive decrease of count rate with an increase of photon fluence in the high-photon-fluence region, while the detectors fabricated from chlorine-doped crystals did not. Results from current-voltage characteristics of the detectors indicated that the different counting characteristics of these detectors originated from the difference in internal electric fields in each detector.
Increased levels of epidermal growth factor receptor have been reported in a variety of tumors, including pulmonary squamous cell carcinomas in man. The purpose of this study was to determine if increased levels of epidermal growth factor (EGFR) were present in lung tumors from Beagle dogs that had been exposed to "2"3"9PuO_2- Using immunohistochemical techniques, sections from 17 lung tumors were examined for the presence of EGFR. Seven of the tumors were strongly positive for EGFR; the remainder of the tumors and the normal lung sections were negative. The positive immunostaining could not be correlated with the histologic phenotype of the tumors. Work is in progress to determine the level of EGFR in preneoplastic, proliferative epithelial foci in the Iung. (author)
Bent specimens of A533B steel (0.16wt% Cu) were irradiated at 290degreeC to 1dpa with 6.4MeV Fe3+ ions. Calculated tensile stresses at the irradiated surface were set to 0, 250, 500 and 750MPa. The specimens were subjected to hardness measurements, transmission electron microscopy (TEM) observations and three-dimensional atom probe (3DAP) analysis. The radiation-induced hardening decreased with increasing stress to 500MPa which was near the yield strength. TEM and 3DAP results showed that well-defined dislocation loops and solute clusters were formed. The diameter of dislocation loops increased and the number density decreased when the stress was applied, whereas the diameter and number density of solute clusters decreased. The hardening was mainly attributed to solute cluster formation. A...
A review of the deep-level defects observed in both electron- and proton-irradiated GaAs solar cells is presented. Studies of the effects of periodic and continuous thermal annealing on the radiation-induced electron and hole traps and the recombination parameters in GaAs solar cells were made for a wide range of electron and proton energies, fluence, annealing temperature and annealing time. A refined model for numerical simulations of the displacement damage was developed for computing the defect density and the cell parameters in the electron- and proton-irradiated GaAs solar cells. Excellent agreement was obtained between the calculated values and the experimental data for the proton-irradiated GaAs solar cells. (orig.).
Data are presented to support the hypothesis that the initial step in the morphologic transformation of irradiated rodent (BALB/3T3) cells is a frequent cellular event involving a large fraction of the irradiated population. This process appears to involve DNA damage, but not to represent a targeted mutation in specific structural gene(s). Morphologic transformation and immortalization appear to be distinct steps in the overall process of transformation. In contradistinction to rodent cells, immortalization is a very rare event in human diploid cells which is induced at extremely low frequencies. The hypothesis is presented that immortality develops among clones of cells bearing stable chromosomal rearrangements which emerge during the proliferation of a population of radiation damaged cells.
Application of gamma radiation as a physical method of disinfestations against melon flies was recognized as a potential quarantine treatment. At 50 Gy, oocytes showed degeneration one day after treatment whereas seven-day-old oocytes did not differ greatly in appearance from control groups. Abnormal enlargement of trophocyte cells and vacuolization of oocytes occurred predominantly following the treatment with 100 and 150 Gy. One day after treatment with 150 Gy trophocytes underwent hypertrophy and hyperplasia. Irradiation at 100 and 150 Gy reduced the fertility to almost zero percent in the female melon flies.(authors)
The content and biosynthesis of glycosaminoglycans (GAGs) were studied in pig thigh muscle after acute local {gamma}-irradiation. Seven months following irradiation, the muscular tissue next to the irradiation cone was replaced by severe mutilating fibrosis delimited by an intermediary perifibrotic zone. Results showed a parallel increase of collagen and GAG content in perifibrotic and fibrotic tissues. Sulphated GAGs, heparan sulphate and dermatan sulphate were preferentially accumulated in fibrotic tissue, while the hyaluronic acid content increased only slightly. Synthesis of sulphated GAGs was more elevated in fibrotic tissue than in perifibrotic zone as compared with normal muscle. Seven months after irradiation well-developed fibrotic tissue continued to synthesize and to accumulate extracellular matrix macromolecules. (Author).
The dependence of the carrier concentrations, of the resistivity and of the Hall coefficient of irradiated silicon on the neutron fluences has been investigated, starting from the supposition that the main phenomena induced by irradiation in the semiconductor bulk are shallow-donor removal and deep-centres creation. The free parameters of the model are initial doping of the starting material, the permitted energy level values of the radiation-induced centres in the semiconductor band gap and their introduction rates. The influence of each parameter on the calculated dependences is studied in detail, for three cases: one deep acceptor-like centre, two deep acceptors and one deep acceptor plus one deep donor-like centre. each of the three cases is discussed in correspondence with different experimental results.
The neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene structure. The murine {alpha}7 shares amino acid identity of 99% and 93% with the rat and human {alpha}7 ...
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. The authors have investigated whether common cellular DNA domains might be rearranged, possibly by HBV integration, in human primary liver tumors. Unique cellular DNA sequences adjacent to an HBV integration site were isolated from a patient with hepatitis B surface antigen-positive hepatocellular carcinoma. These probes detected rearrangement of this cellular region of chromosomal DNA in 3 of 50 additional primary liver tumors studied. Of these three tumor samples, two contained HBV DNA, without an apparent link between the viral DNA and the rearranged allele; HBV DNA sequences were not detected in the third tumor sample. By use of a panel of somatic cell hybrids, these unique cellular DNA sequences were shown to be located on chromosome 4. Therefore, this region of chromosomal DNA might be implicated in the formation of different ...
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. The authors have investigated whether common cellular DNA domains might be rearranged, possibly by HBV integration, in human primary liver tumors. Unique cellular DNA sequences adjacent to an HBV integration site were isolated from a patient with hepatitis B surface antigen-positive hepatocellular carcinoma. These probes detected rearrangement of this cellular region of chromosomal DNA in 3 of 50 additional primary liver tumors studied. Of these three tumor samples, two contained HBV DNA, without an apparent link between the viral DNA and the rearranged allele; HBV DNA sequences were not detected in the third tumor sample. By use of a panel of somatic cell hybrids, these unique cellular DNA sequences were shown to be located on chromosome 4. Therefore, this region of chromosomal DNA might be implicated in the formation of different ...
We investigated possible mechanism(s) where honokiol induces apoptosis in human hepatocellular carcinoma SMMC-7721 cells. MTT assay showed that honokiol has strong inhibition on SMMC-7721 cells in a dose-dependent manner. SMMC-7721 cells after honokiol treatment display morphological characteristics such as cell shrinkage, detachment from the culture plate, formation of apoptotic bodies, change to a round shape, and marked nuclear condensation and fragmentation after 32258 staining. Cell apoptosis was measured by Annexin-V/PI staining and alternatively, by the subG0/G1 percentage of the cell cycle analysis followed by FACS. An obvious loss of ??(m) and a quick burst of ROS was detected when honokiol reached 4?g/ml, which was coincident with the high apoptosis percentage in our previous research. Up-regulation of Bax and down-regulation of Bcl-2 were observed, suggesting that honokiol-induced apoptosis was associated with reactive oxygen species (ROS) production and ...
{sup 99m}Tc-N-pyridoxyl-5-methyl-tryptophan (PMT) scintigraphy, which exhibits highly specific for the diagnosis of primary hepatocellular carcinoma (HCC), was performed for recurrent HCC following non-surgical treatment. Eighty-four patients (total 351 examinations) were selected for the study. The ability of PMT scintigraphy to diagnose recurrent HCC after treatment was compared with that of computed tomography, ultrasonography and angiography. The results showed that sixty-three (75%) of 84 cases demonstrated positive findings during our follow-up period, most of the tumors initially showing positive findings remained PMT positive when they recurred and PMT studies shortly after treatment demonstrated wider tracer uptake rather than the actual tumor area. In conclusion, PMT scintigraphy for patients with HCC after non-surgical treatment exhibited high accuracy in identifying viable HCC only for tumors indicating positive findings. (author)
Our purpose was to investigate the usefulness of Lipiodol-CT for detection of residual viable neoplastic tissue in hepatocellular carcinoma (HCC) lesions treated by means of percutaneous ethanol injection (PEI). An emulsion of 5 to 20 ml iodized oil and 50 to 70 mg doxorubicin hydrochloride was intraarterially injected in 18 patients with 25 HCC lesions treated by means of PEI one to 24 months before. At CT performed 3 to 5 weeks after injection, retention of Lipiodol was observed in 9 of 13 tumors that still contained viable neoplastic tissue and in 2 of 12 tumors proven to have undergone complete necrosis after PEI. The sensitivity and specificity of Lipiodol-CT were 69.2% and 83.3%, respectively. Thus, Lipiodol-CT seems to have limited diagnostic value after PEI, probably as a consequence of the alcohol-induced vascular damage, accounting for both false-negative and false-positive results. (orig.).
Early diagnosis of hepatocellular carcinoma (hepatoma) along with surgical resection is the most appropriate therapeutic modality. For this purpose, there have been many reports concerning the diagnostic value of Lipiodol-CT scan. The authors selected 45 patients with hepatoma during the period of Feb.1986 to Jan. 1988 who received a conventional CT scan, hepatic angiography and a Lipiodol-CT scan. The results were as follows: 1. There was no statistical significant between serum AFP level and mass size, morphology and amount of necrosis. 2. Tumor necrosis was observed in a single massive and multinodular type when the tumor size exceeded 5 cm. 3. Pattern II on Lipiodol-CT, homogenous accumulation of Lipiodol except for the area of inner necrosis, was most frequently demonstrated, which means that a tumor mass with hypervascularity and increased blood flow will attract Lipiodol better. 4. Lipiodol-CT was superior to conventional CT in detecting small, daughter ...
Glypican-3 (GPC3), a membrane-bound heparan sulfate proteoglycan, is found to be overexpressed in hepatocellular carcinoma (HCC). The purpose of the present study was to investigate the possible role of GPC3 in the development of HCC. In this study, RNA interference (RNAi) with a GPC3 small hairpin RNA (GPC3 shRNA) was used to identify the effects of GPC3 on the regulation of malignant behaviors of HCC. MHCC97-H, a highly metastatic human HCC cell line in which GPC3 mRNA and protein levels were detected as the highest among the 4 HCC cell lines assessed in this study, and was thus selected as a cell model for in vitro and in vivo experiments. The results showed that down-regulation of GPC3 can significantly inhibit the proliferative and invasive ability of MHCC97-H. Compared with the parental HCC cells, GPC3-silenced cells exhibited attenuated capacities in developing tumors in nude mice, while the growth of tumor xenografts derived from these cells dramatically ...
The liver is a primary target of growth hormone (GH). GH signals are mediated by the transcription factor signal transducer and activator of transcription 5 (STAT5). Here, we focus on recent discoveries about the role of GH-STAT5 signaling in hepatic physiology and pathophysiology. We discuss roles of the GH-STAT5 axis in body growth, lipid metabolism, and the cell cycle pertaining to hepatosteatosis, fibrosis, and hepatocellular carcinoma. Finally, we discuss recent discoveries about the role of GH-STAT5 in sex-specific gene expression and bile acid, steroid, and drug metabolism.
Faced with increasing indications for the use of iodine-131 labelled lipiodol in the treatment of hepatocellular carcinoma (HCC), it appears essential to develop an individualized dosimetrY so we can predict the potential effectiveness of this treatment and adjust the activity to be injected. We developed a dosimetric protocol based on imagery and dedicated to calculation of the tumoral dose during the treatment of hepatocellular carcinoma by iodine-131 labelled lipiodol. This concept was developed on a SPECT- CT gantry, and integrates corrections for the phenomena of attenuation, diffusion and dead time. The dose is calculated according to the formalism proposed by the Medical Internal Radiation Dose Committee (MIRD). This protocol was applied to a series of 41 patients in the framework of a retrospective study. The results obtained in terms of biodistribution are compatible with previously published data. The total biological response rate is ...
A prospective pilot trial was performed in 20 patients randomised to receive either {sup 131}I-Lipiodol therapy alone (n=10) or {sup 131}I-Lipiodol combined with a short low-dose cisplatin infusion (n=10), the aim being to evaluate the possible positive influence of a radiosensitiser on toxicity and tumour response. An activity of 1,354-2,128 MBq (mean 1,824 MBq) [36.6-57.5 mCi (mean 49.3 mCi)] {sup 131}I-labelled Lipiodol was administered by selective instillation in the hepatic artery. Cisplatin was given in a dose of 30 mg/m{sup 2} at day -1 and day +6 (day 0: {sup 131}I-Lipiodol). The primary endpoint of this trial was toxicity of therapy; points of secondary interest were tumour response and survival at 6 months. With the use of cisplatin we found a higher percentage of stable or diminished tumour size (90%, vs 40% without). A benefit in group survival at 6 months was not evident. Low-grade stomatitis in one patient and minor changes in peripheral blood count were probably ...
Hepatocellular carcinoma (HCC) is characterized by tumor vascularization from the hepatic artery. The objective of our work was to compare color Doppler ultrasonography (CDU), including power Doppler ultrasonography (PDU) with radiographic imagings with contrast medium in regard to the detection of the arterial tumor vascularity of small hepatocellular carcinomas (HCC). We examined 42 small HCC lesions 2 cm or less in diameter in 37 patients for arterial tumor vascularity by conventional CDU, PDU, dynamic computed tomography (dCT), digital subtraction angiography (DSA), and CT hepatic arteriography (CTA). Color images were detected in 25 (59.5%) and 28 (66.7%) of the 42 lesions with conventional CDU and PDU, respectively, and tumor vascularity was detected in 26 (61.9%) by dCT, 23 (54.8%) by DSA, and 29 (69.0%) by CTA. Tumor vascularity could be detected in 51.9% by PDU and CTA, more than by conventional CDU, dCT, and DSA (44.4, 44.4, and ...
On 21 October 1994, three brothers entered a waste repository at Tammiku, Estonia, without authorization and removed a metal container enclosing a caesium-137 source. During the removal the source was dislodged and fell to the ground. One of the men picked up the source, placed it in his pocket and took it to his home in the nearby village of Kiisa. Very soon after entry into the repository he began to feel ill, and few hours later he began to vomit. The man was subsequently admitted to hospital with severe injuries to his leg and hip and died on 2 November 1994. The injury and subsequent death were not attributed to radiation exposure, and the source remained in the man's house with his wife and stepson and the boy's great-grandmother. The boy was hospitalized on 17 November with severe burns on his hands, and these were identified by a doctor as radiationinduced. The authorities were alerted, and the Estonian Rescue Board recovered the ...
Metal oxide semiconductor (MOS) integrated circuits, with the benefits of low power consumption, represent the state of the art technology for implantable medical devices. Three significant sources of radiation are classified as having the ability to damage or alter the behavior of implantable electronics; Secondary neutron cosmic radiation, alpha particle radiation from the device packaging and therapeutic doses(up to 70 G{gamma}) of high energy radiation used in radiation oncology. The effects of alpha particle radiation from the packaging may be eliminated by the use of polyimide or silicone rubber die coatings. The relatively low incidence of therapeutic radiation incident on an implantable device and the use of die coating leaves cosmic radiationinduced secondary neutron single event upset (SEU) as the main pervasive ionising radiation threat to the reliability of implantable devices. A theoretical model which predicts the susceptibility ...
Endothelial dysfunction and increased platelet aggregation may be involved in the pathogenesis of normal tissue radiation toxicity. This study assessed clopidogrel, an inhibitor of ADP-induced platelet aggregation, as a modulator of intestinal radiation injury (radiation enteropathy). Rat small intestine was exposed to 21 Gy X-radiation. Clopidogrel (20 mg/kg/day) or vehicle was administered from 2 days before to 10 days after irradiation. Structural radiation injury, neutrophil infiltration, smooth muscle cell proliferation, collagen content, and TGF-beta1 expression were assessed 2 weeks (early phase) and 26 weeks (delayed phase) after irradiation, using quantitative histology and immunohistochemistry, morphometry, and real-time fluorogenic probe RT-PCR. Irradiated intestine exhibited significant histopathologic injury, reduced mucosal surface area, vascular sclerosis, intestinal wall fibrosis, increased collagen content, and increased TGF-beta1 expression. Clopidogrel reduced ...
In-reactor testing of bolt-loaded compact tension specimens was performed in 360 C water to determine the irradiation-assisted stress corrosion cracking (IASCC) behavior of HTH Alloy X-750 and direct-aged Alloy 625. New data confirm previous results showing that high irradiation levels reduce SCC resistance in Alloy X-750. Heat-to-heat variability correlates with boron content, with low boron heats showing improved IASCC properties. Alloy 625 is resistant to IASCC, as no cracking was observed in any Alloy 625 specimens. Microstructural, microchemical and deformation studies were performed to characterize the mechanisms responsible for IASCC in Alloy X-750 and the lack of an effect in Alloy 625. The mechanisms under investigation are: boron transmutation effects, radiation-induced changes in microstructure and deformation characteristics, and radiation-induced segregation. Irradiation of Alloy X-750 caused significant strengthening and ductility ...
7,959 patients were examined by radionuclide in-vivo methods within one year, 1,228 of them by application of "1"3"1I-iodide (radioiodine test and scintigraphy of the thyroid gland). In compliance with the ICRP publications 26 and 27 the somatically effective equivalent dose H/sub s,eff/ was ascertained for several examining methods, derived from it the collective dose S/sub s,eff/ and considering a part of manifestation resulting from the age distribution of patients, the somatic risk regarding radiation-induced malignoma with fatal termination. For the patients examined by "1"3"1I-iodide the collective dose was 79.9 man x Sv and the mean somatic risk 30 x 10"-"5 with a part of manifestation of 0.39 accordig to 0.37 radiation-induced malignomas with fatal termination. For all patients examined by other radiopharmaceuticals the collective dose was 14.07 man x Sv, the mean somatic risk 1.7 x 10"-"5 according to 0.11 malignomas. The average ...
Correlation between mechanical stress and hydrogen effects on radiation damage in polycide-gate MOS capacitors was investigated as a function of gate-oxide thickness. The compressive stress magnitude was altered by varying the silicide (TiSi/sub 2/ or WSi/sub 2/) thickness in the polycide-gate electrode, and hydrogen introduction into gate-SiO/sub 2/ film was carried out by diffusion from plasma-deposited silicon-nitride passivation film (SiN-Cap). In a MOS capacitor without passivation film (No-Cap sample), it was found that compressive stress on gate-SiO/sub 2/ reduces both positive charge build-up (..delta..Qot) and interface-trap generation (..delta..Dit). Radiationinduced shift, ..delta..Qot exhibits a smaller stress effect as compared with ..delta..Dit. As gate-SiO/sub 2/ thickness decreases, the stress effect on ..delta..Qot increases, while this effect on ..delta..Dit remains nearly constant. This compressive stress effect was ...
Jittery (ji) is a recessive mouse mutation on Chromosome 10 characterized by progressive ataxic gait, dystonic movements, spontaneus seizures, and death by dehydration/starvation before fertility. Recently, a viable neurological recessive mutation, hesitant, was discovered. It is characterized by hesitant, uncoordinated movements, exaggerated stepping of the hind limbs, and reduced fertility in males. In a complementation test and by genetic mapping we have shown here that hesitant and jittery are allelic. Using several large intersubspecific backcrosses and intercrosses we have genetically mapped ji near the marker Amh and microsatellite markers D10Mit7, D10Mit21, and D10Mit23. The linked region of mouse Chromosome 10 is homologous to human 19p13.3, to which several human ataxia loci have recently been mapped. By excluding genes that map to human 21q22.3 (Pfkl) and 12q23 (Nfyb), we conclude that jittery is not likely to be a genetic ...
Apoptosis is a pattern of cell death involving nuclear pycnosis, cytoplasmic condensation, and karyorrhexis. Apoptosis induced by continuous irradiation with gamma rays (externally given by a 137Cs source) or with beta rays (from tritiated water injected ip) was quantified in the crypts of two portions of mouse bowel, the small intestine and descending colon. The time-course change in the incidence of apoptosis after each type of radiation could be explained on the basis of the innate circadian rhythm of the cells susceptible to apoptotic death and of the excretion of tritiated water (HTO) from the body. For 6-h continuous gamma irradiation at various dose rates (0.6-480 mGy/h) and for 6 h after injection of HTO of various radioactivities (0.15-150 GBq per kg body wt), the relationships between dose and incidence of apoptosis were obtained. Survival curves were then constructed from the curves for dose vs incidence of apoptosis. For the calculation of the absorbed ...
We cloned and characterized horse preproendothelin-2 (PPET-2) cDNA from intestinal tissue. The cDNA encoded 178 amino acids of the PPET-2 polypeptide, in which a 21-amino-acid mature endothelin-2 peptide and a 16-amino acid endothelin-2-like peptide were found. For the open reading frame the correspondence of horse PPET-2 cDNA with those of the ferret, human, dog, mouse and rat was 85.1%, 84.9%, 82.1%, 77.8% and 77.2%, respectively. Analysis of the organ distribution of PPET-2 mRNA by reverse transcription-polymerase chain reaction demonstrated that the kidney, stomach and small intestine are major sites of expression of the PPET-2 gene. Surprisingly, the mRNA is not detected in the large intestine, where high expression is demonstrated in the mouse and rat. This difference may result from the underlying functional differences of the large intestine between a herbivore (horse) and an omnivore (mouse and rat). PMID:15838341
Yeast artificial chromosome (YAC) libraries have been difficult to construct with average insert sizes >400 kilobase pairs when DNA is size-fractionated in low-melting-point agarose. By using yeast chromosomes in mock cloning experiments, the authors found that polyamines should be present whenever agarose containing high molecular weight DNA is melted to protect DNA from degradation. By incorporating polyamines during the cloning procedure, they constructed YAC libraries from mouse and human DNA with average insert sizes of 700 and 620 kilobase pairs, respectively. Several genome equivalents of these YAC libraries were replicated onto the surface of many duplicate agar plates using a 40,000 multipin transfer device. High-density filter replicas were screened by hybridization, and 70 mouse YAC clones from 31 loci and 132 human YAC clones from 49 loci were isolated.
The retinal degeneration 10 (rd10) mouse is a well-characterized model of autosomal recessive retinitis pigmentosa (RP), which carries a spontaneous mutation in the ? subunit of rod cGMP-phosphodiesterase (PDE?). Rd10 mouse exhibits photoreceptor dysfunction and rapid rod photoreceptor degeneration followed by cone degeneration and remodeling of the inner retina. Here, we evaluate whether gene replacement using the fast-acting tyrosine-capsid mutant AAV8 (Y733F) can provide long-term therapy in this model. AAV8 (Y733F)-smCBA-PDE? was subretinally delivered to postnatal day 14 (P14) rd10 mice in one eye only. Six months after injection, spectral domain optical coherence tomography (SD-OCT), electroretinogram (ERG), optomotor behavior tests, and immunohistochemistry showed tha...
Objective: To study the effects of minocycline hydrochloride (MINO) on the formation of tartrate-resistant acid phosphatase (TRAP) staining-positive multinucleated osteoclast-like cells in mouse bone marrow cells (BMCs) treated with 1@a,25(OH)"2D"3 or soluble receptor activator of nuclear factor-@kB ligand (s-RANKL). Materials and methods: Mouse BMCs were cultured in alpha-modified minimum essential medium containing foetal calf serum (10%) and tetracyclines (2.5, 5 and 10@mM), such as MINO, tetracycline hydrochloride (TC), oxytetracycline hydrochloride (OXT) or doxycycline (DOXY) in the presence of 1@a,25(OH)"2D"3 (10nM) or s-RANKL (20ng/ml) for 7 days, and the number of TRAP staining-positive osteoclast-like cells was counted. In RNA isolated from BMCs treated with 1@a,25(OH)"2D"3 or s-R...
Attention deficit disorder (ADHD) is a complex biobehavioral phenotype which affects up to 8% of the general population and often impairs social, academic, and job performance. Its origins are heterogeneous, but a significant genetic component is suggested by family and twin studies. The murine strain, coloboma, displays a spontaneously hyperactive phenotype that is responsive to dextroamphetamine and has been proposed as a genetic model for ADHD. Coloboma is a semi-dominant mutation that is caused by a hemizygous deletion of the SNAP-25 and other genes on mouse chromosome 2q. To test the possibility that the human homolog of the mouse coloboma gene(s) could be responsible for ADHD, we have carried out linkage studies with polymorphic markers in the region syntenic to coloboma (20p11-p12). Five families in which the pattern of inheritance of ADHD appears to be autosomal dominant were studied. Segregation analysis of the traits studied suggested ...
We used a 13-year time series of abundance estimates of breeding Northern Saw-whet Owls (Aegolius acadicus), and of small mammals from central Ontario, Canada, to assess the numerical response of the owls to small-mammal prey species. We found that the finite rate of increase of breeding owls was directly related to estimates of red-backed vole (Myodes gapperi) abundance. Thus, it appeared that the owls were nomadic, and made decisions about where to breed based on vole supply. The owls showed a much weaker response to deer mouse (Peromyscus maniculatus) abundance. Across all years, 55% of variation in owl rate of increase could be uniquely attributed to vole abundance, whereas only 3% could be attributed to mouse abundance. Consistent with the model of nomadism, there was only a weak rela...
The yellow Iranian scorpion Odontobuthus doriae can cause fatal envenoming, but its mechanism of action is unclear. One of the reported manifestations of envenoming is moderate to severe involuntary tremor of skeletal muscle. In order to understand better the mechanism of action of this venom on skeletal muscle function, we examined the effects of the venom in vitro on chick biventer cervicis (CBC) and mouse hemidiaphragm (MHD) nerve muscle preparations. O. doriae venom (0.3-10mg/ml) initially increased and then decreased twitch height. The venom also caused contracture in both preparations. In mouse triangularis sterni preparations, used for all intracellular recording techniques, the venom enhanced the release of acetylcholine and induced repetitive firing of nerve action potentials and ...
The present study was aimed at investigating effects of nickel (NiCl2) on secretion of testosterone (T), cell viability, ultrastructure and apoptosis in mouse Leydig cells. Testosterone release was measured after 48h of culture with 15.67, 31.25, 62.5, 125, 250, 500 and 1000mmol/L NiCl2 or without NiCl2 using radioimmunoassay. Cell viability was assessed by a MTT (metabolic activity assay). Quantification of apoptotic cells was performed using TUNEL assay and the ultrastructural changes were analyzed using transmission electron microscopy. The viability was decreased after addition of >=250mmol/L NiCl2. A concentration-dependent depression of T production was observed. The percentage of apoptotic cells was significantly increased only after addition of 125, 250 and 1000mmol/L NiCl2. After ...
The 50th anniversary of Mary Lyon?s 1961 Nature paper, proposing random inactivation in early embryonic life of one of the two X chromosomes in the cells of mammalian females, provides an opportunity to remember and celebrate the work of those involved. While the hypothesis was initially put forward by Lyon based on findings in the mouse, it was founded on earlier studies, notably the work of Susumu Ohno; it was also suggested independently by Beutler and colleagues using experimental evidence from a human X-linked disorder, glucose-6-phosphate dehydrogenase deficiency, and has proved to be of as great importance for human and medical genetics as it has for general mammalian genetics. Alongside the hypothesis itself, previous cytological studies of mouse and human chromosomes, and the obse...
Background Identifying susceptibility genes for endophenotypes by studying analogous behaviors across species is an important strategy for understanding the pathophysiology underlying psychiatric disorders. This approach provides novel biological pathways plus validated animal models critical for selective drug development. One such endophenotype is avoidance behavior. Methods In the present study, novel automated registration methods for longitudinal behavioral assessment in home cages are used to screen a panel of recently generated mouse chromosome substitution strains that are very powerful in quantitative trait loci (QTL) detection of complex traits. In this way, we identified chromosomes regulating avoidance behavior (increased sheltering preference) independent of motor activity lev...
Prepulse inhibition (PPI) is a measure of sensorimotor gating, a pre-attentional inhibitory brain mechanism that filters extraneous stimuli. Prepulse inhibition is correlated with measures of cognition and executive functioning, and is considered an endophenotype of schizophrenia and other psychiatric illnesses in which patients show PPI impairments. As a first step toward identifying genes that regulate PPI, we performed a quantitative trait locus (QTL) screen of PPI phenotypes in a panel of mouse chromosome substitution strains (CSSs). We identified five CSSs with altered PPI compared with the host C57BL/6J strain: CSS-4 exhibited decreased PPI, whereas CSS-10, -11, -16 and -Y exhibited higher PPI compared with C57BL/6J. These data indicate that A/J chromosomes 4, 10, 11, 16 and Y harbor...
Research on hematological disorders relies on suitable animal models. We retrospectively evaluated the use of the hematological parameters hematocrit (HCT), hemoglobin (HGB), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), red blood cell count (RBC), white blood cell count (WBC), and platelet count (PLT) in the phenotype-driven Munich N-ethyl-N-nitrosourea (ENU) mouse mutagenesis project as parameters for the generation of novel animal models for human diseases. The analysis was carried out on more than 16,000 G1 and G3 offspring of chemically mutagenized inbred C3H mice to detect dominant and recessive mutations leading to deviations in the levels of the chosen parameters. Identification of animals exhibiting altered valu...
The expression of motor activity levels in response to novel situations is under complex genetic and environmental control. Several genetic loci have been implicated in the regulation of this behavioral phenotype, but their relationship to epigenetic and epistatic interactions is relatively unknown. Here, we report on a quantitative trait locus (QTL) on mouse chromosome 1 for novelty-induced motor activity in the open field, using chromosome substitution strains derived from a high active host strain (C57BL/6J) and a low active donor strain (A/J). The QTL for open field (horizontal distance moved) peaked at the location of Kcnj9, however, QTL detection was initially masked by an interplay of both grandparent genetic origin and genetic co-factors influencing behavior on chromosome 1. Our fi...
Purpose Evaluation of the all-trans retinoic acid (t-RA) effects on in vitro maturation (IVM) and in vitro fertilization (IVF) of immature mouse oocytes in the presence and absence of granulosa cell monolayer. Methods Denuded oocytes isolated from mice ovaries and matured in IVM medium alone (Control I), IVM medium in the presence of granulosa cells (Control II), IVM medium with t-RA (Experimental I) and IVM medium simultaneously with t-RA and granulosa cells (Experimental II). After 24?h, matured oocytes were fertilized in T6 medium and their development was followed until the blastocyst stage. Metaphase II oocytes ploidy were evaluated by chromosome counting. Results The t-RA group compared to the control groups showed no obvious abnormalities. Additionally maturation and embryo developm...
Please cite this paper as: Ectopic mineralization of connective tissue in Abcc6-/- mice: effects of dietary modifications and a phosphate binder - a preliminary study. Experimental Dermatology 2008; 17: 203-207. Abstract: Pseudoxanthoma elasticum (PXE), a heritable multisystem disorder, is caused by mutations in the ABCC6 gene. We have developed a murine model for PXE by targeted inactivation of the corresponding mouse gene. A feature of this mouse model is ectopic mineralization of connective tissue capsule surrounding the bulb of vibrissae. This study was designed to investigate the effect of dietary sevelamer hydrochloride (Renagel), a phosphate binder, and specific mineral modifications on ectopic mineralization of connective tissue in Abcc6-/- mice. Three groups were fed a specific di...
Excessive physical activity plays an important role in the progression of anorexia nervosa (AN) by accelerating weight loss during dietary restriction. To search for mechanisms underlying this trait, a panel of mouse chromosome substitution strains derived from C57BL/6J and A/J strains was exposed to a scheduled feeding paradigm and to voluntary running wheel (RW) access. Here, we showed that A/J chromosomes 4, 12 and 13 contribute to the development of a disrupted RW activity in response to daily restricted feeding. This pattern is characterized by intense RW activity during the habitual rest phase and leads to accelerated body weight loss. Regions on mouse chromosomes 4, 12 and 13 display homology with regions on human chromosomes linked with anxiety and obsessionality in AN cohorts. The...
Two lines of mouse tumor cells were shown to be capable of aggregating mouse and rabbit platelets in vitro. This process required higher Mg/sup 2 +/ concentrations than were needed by other commonly used platelet-aggregating agents. Platelet-aggregating activity was also found in tumor cell membrane fragments. This membrane-bound platelet-aggregating material contained protein, lipid, and carbohydrate moieties. The presence of all three appeared to be essential for stimulating platelet aggregation. Destruction of any component abolished its activity. Platelet aggregation induced by tumor cell membrane fragments was associated with a secretory release reaction. In this process, growth-promoting activity for tumor cells was also released from platelets. These results underline the importance of platelets in establishing tumor metastases.
The purpose of this paper is to report the personal experience with helical CT evaluation of hepatocellular carcinoma treated with various percutaneous interventional procedures. From December 1996 to September 1998 it were examined with helical CT 41 patients (73 nodules in all) with hepatocellular carcinoma treated with percutaneous ablation therapies: conventional ethanol injection in 18 subjects (31 nodules), one-shot ethanol injection 3 (8 nodules), radiofrequency thermal ablation in 16 (25 nodules), and combined chemo embolization and ethanol injection in 4 (9 nodules). CT performed was 4-27 days after the last session, acquiring biphasic volumetric images in 14 patients and triphasic volumetric images in 27. A second treatment with subsequent CT study was performed for 28 lesions; 15 underwent 3 serial studies and 6 underwent 4 studies. Compared with pretreatment findings, the diameter was unchanged in 62% of the nodules and increased in ...
The "1"3"1-radioiodine use in Guanabara area, during 1972-1973, is analysed. References are made to the radiation levels delivered to thyroid, bone marrow and gonads in a population of 27000 people examined by tracer techniques, 190 submitted to hyperthyroidism treatment and 50 treated for thyroid cancer. The pertinent literature gives some data concerning radiationinduced cancer (leukaemia and thyroid cancer). By this, it was possible to estimate the probability of tumour occurrence in that population, assuming a linear relationship between dose and effect. The conclusions are the followings: 1 - there are many duties in this field at the present; 2 - the leukaemia incidence related to the 131-radioiodine use is negligible, either in diagnostic or therapeutic modalities; 3 - the possibility of thyroid tumors induced by radiation is real, specially in hyperthyroidism treatment; 4 - the use of tracer techniques that cause lower irradiation to ...
A series of copolymers based on the cellulose acetate/propionate-g.co-acrylic acid system has been prepared under radiation-induced control. These copolymers have been assessed for their water-retention capacity both in an unmodified state and after ''decrystallization'' or ''neutralization'' treatments. The grafting of acrylic acid onto the cellulose acetate/propionate had little effect on the water retention power of the cellulose acetate/propionate. However, improvements to the water retentivity was obtained after ''decrystallization'' procedures had been carried out on the copolymers using selected alkali metal salts with methanol as the continuous medium. The water-retentivity of the copolymers increased with increase in the extent of grafting, though the effect is less pronounced at high graft levels. Neutralization of the functional groups of the ...
Ionizing radiation, mainly in the form of #gamma#-rays from the radioisotope cobalt 60, is being used increasingly for the inactivation of contaminants in cosmetic and toiletry preparations. The treatment is applied to the product in its final pack, and therefore, it is important to recognize that the properties of the packaging materials could be affected, particularly if high radiation doses are used. The stability of a wide range of materials is discussed. The nature and extent of chemical and physical changes in plastics very much depends on the presence of antioxidants and other additives, and on the environmental conditions during irradiation. Some useful information is available from research into the use of radiation for the preservation of food - many films and laminates have been cleared for use in the United States. The low radiation doses used for the control of contaminants in cosmetic products are quite unlikely to cause changes in packaging materials which will limit the ...
The effects of the structure of a carboxylic acid on the processes of oxidation and reduction of iron ions in irradiated aqueous solutions were directly observed during irradiation. The solutions contained the mono- or dicarboxylic acid, H/sub 2/SO/sub 4/, Fe(NH/sub 4/)/sub 2/(SO/sub 4/)/sub 2/ and O/sub 2/. Th e ferrous oxidation was rather independent of the acid and its concentration, but the reduction of ferric was possible in the presence of formic, oxalic, or valeric acid only. The radical formed from the valeric acid acts similar to those formed from hydrocarbons. The G-values of oxidation and reduction of the iron ions were established. The molar extinction coefficients for oxalic and malonic complexes of ferric ions were determined. (auth)
The spectral energy-dependence of the radiation-induced ESR signal has been studied in ovine cortical bone. Crushed bone samples were irradiated using photon beams with effective energies in the range from 0.06 to 6 MeV, and electron beams with mean energies in the range from 2 to 10 MeV. The photon and electron data were normalized to a dose to bone of 50 Gy and the results are reported as response relative to the ESR signal for photon irradiation at 1.25 MeV ("6"0Co). The photon irradiation results show that the ESR response is greatest at low energies with a relative value of 1.2 at 0.06 MeV. The relative response decreases, as the energy increases, to approximately 0.85 in the region of 2 to 3 MeV. These variations in the relative ESR responses are significantly less than the ESR energy-dependent responses reported in the literature for human tooth enamel and synthetic hydroxyapatite. An explanation for this difference is offered. For electron beam ...
To determine if barbiturates would protect brain at high doses of radiation, survival rates in rats that received whole-brain x-irradiation during pentobarbital- or lidocaine-induced anesthesia were compared with those of control animals that received no medication and of animals anesthetized with ketamine. The animals were shielded so that respiratory and digestive tissues would not be damaged by the radiation. Survival rates in rats that received whole-brain irradiation as a single 7500-rad dose under pentobarbital- or lidocaine-induced anesthesia was increased from between from 0% and 20% to between 45% and 69% over the 40 days of observation compared with the other two groups (p less than 0.007). Ketamine anesthesia provided no protection. There were no notable differential effects upon non-neural tissues, suggesting that pentobarbital afforded protection through modulation of ambient neural activity during radiation exposure. Neural suppression during high-dose cranial irradiation ...
The high-energy radiation-induced degradation of an H-acid derivative azo dye, Apollofix-Red SF-28 (AR-28) was studied in aqueous solution by using pulse radiolysis with kinetic spectroscopic detection for transient measurements. Gamma radiolysis with UV-VIS spectroscopy and gradient ionpair HPLC separation with diode array detection were applied for following the destruction of AR-28 and measuring the products. The reactions of hydrated electron (e_a_q "-) and hydroxyl ("#centre dot#OH) radical were investigated separately. "#centre dot#OH reacts with the unsaturated bonds of the molecule. In the further reactions of the "#centre dot#OH adduct radicals, the AR-28 molecules partly reform with a slightly modified structure. The products formed in the first reaction of "#centre dot#OH and AR-28 molecules have also high reactivity towards the "#centre dot#OH radicals. For these reasons the efficiency of "#centre dot#OH radicals in discolouration of the solution is ...
Current bioartificial extra-corporeal systems are bioreactors where cells are separated from the surrounding media by porous polymeric membranes. The present work focuses on the design of membranes that allow the differential diffusion of plasma metabolites and proteins such as immunoglobulin (IgG). This design will improve catabolites removal and reduce possible immune response and virus infection. We demonstrate the feasibility to synthesize the hydrogels confined to the macroporous structure of membranes by radiation-induced in situ polymerization. The hollow-fiber membranes were soaked in aqueous monomeric solution, rinsed and irradiated while submerged in oil. This procedure confined the hydrogel to the void internal volume of the pores of the membrane. Hydrogels of polyacrylamide and polyHEMA were synthesized this way by irradiation at 10 kGy. Hydraulic permeability and diffusion of glucose, albumin and IgG were measured in these hydrogel-filled membranes. ...
Poly(methyl methacrylate), PMMA, Acrigel, a Brazilian polymer, is used in the manufacture of medical supplies sterelizable by ionizing radiation. However, when PMMA is gamma-irradiated it undergoes main chain scissions, which promote molecular degradation causing reduction in its mechanical properties. Therefore, radiolytic of PMMA is important for it to become commercially radiosterizable. In this work some commercial additives, originally used in photo-and thermo-oxidate stabilization of polymers, were tested. Only two additives, type HALS (Hindered Amine Light Stabilizer), denoted Scavenger, showed a good protective quality. The investigation of radiation-induced main scissions was carried out by viscosimetric method. The most effective additive, added to the polymer system at 0.3 w/w%, promotes a great molecular radioprotection of 93%. That means a reduction of G-value (scissions/100 eV) from 0.611 to 0.053. In addition, the glassy transition temperature (T{sub ...
The atomic explosions in Hiroshima and Nagasaki made the name radiation itself become a nightmare. Notwithstanding this, radiation continued to serve the mankind specially in diagnosis of several human diseases and in the treatment of intractable malignancies. With their latest research tools biologists have now shown a significant shift in the earlier paradigm; even the concept that radiation initiates cancer appears to be no longer tenable. On the contrary, selective radiation doses inhibit growth of cancer cells and radiation in combination with many chemotherapeutic drugs, radiosensitizing chemicals and/or hyperthermia, is emerging as a new modality for cancer treatment which offers high therapeutic advantages. In addition, the deleterious effects of radiation can now be strategically counter poised by the use of many drugs and chemicals. This has been possible by the newer insights gained in the mechanism of biological effects of radiation. The fate of ...
Color formation in aqueous solutions of the ditetrazolium salt blue tetrazolium (BT{sup 2+}) in the absence or presence of oxygen is a complex radiation chemical reaction. The final stable product is the poorly soluble diformazan violet to blue pigment having a broad spectral absorption band ({lambda}{sub max}=552 nm). The reaction of BT{sup 2+} with the hydrated electron proceeds by rapid reduction of BT{sup 2+} followed by protonation at the nitrogen closest to the unsubstituted phenyl group, via the two intermediate tetrazolinyl radicals shared by the ditetrazole ring nitrogens. The effect of solution pH, N{sub 2}O saturation, and the presence of the reducing agent dextrose are examined. The system serves as a radiochromic sensor and a dosimeter of ionizing radiations. Solutions of 5 mmol l{sup -1} BT{sup 2+} at pH 7.3 serve as dosimeters over an absorbed-dose range of approximately 0.2-6 kGy (dearated, with a range of 1-8 mmol l{sup -1} dextrose) and of about 1-15 kGy (aerated, ...
We investigated the effect of irradiation on the kinetic characteristics of amino acid and glucose transport, and the effect on the activity of the cell membrane-bound enzyme 5'-nucleotidase and on the receptor-mediated stimulation of cyclic adenosine monophosphate synthesis by prostaglandin E1. Irradiation inhibited the sodium-dependent amino acid transport by a reduced binding of the amino acid to the transport unit. The transport of glucose, which appeared to be a sodium-independent process, was temporarily stimulated by increased maximal velocity of the transport. No effect was found on the binding to the transport unit. Irradiation increased the 5'-nucleotidase activity and decreased the prostaglandin E1-stimulated cyclic adenosine monophosphate synthesis 48 h after exposure to 20 Gy. It is concluded that irradiation decreases sodium-dependent transport by impairment of the transport unit, does not impair a sodium-independent process, and has opposite effects on ...
Wood sawdust has been applied to manufacture the sawdust-clay-plastic composite (SDCPC) by radiation process for the purpose of disposing large amount of wood sawdust waste material. The process comprises the impregnation of liquid vinyl monomers into the completely dried molded sawdust-clay specimens followed by exposure to Co-60 gamma-radiation to induce graft-copolymerization of the impregnated vinyl monomers onto the sawdust-clay matrix. The comonomer system of unsaturated polyester and vinyl compounds was found to be the ideal impregnating monomer for the preparation of the SDCPC from the viewpoint of the technological and economical advantages. The SDCPC material has a variety of the sawdust content which enables the composite to have wide range of mechanical properties, e.g., 410 to 1100 kg/cm/sup 2/ in compressive strength, 120 to 380 kg/cm/sup 2/ in tensile strength and 0.32 to 4.41 kg/mm/sup 2/ in static bending strength. The SDCPC having higher content of clay (more than 50% ...
A brain weight deficit of about 70 mg was induced at doses of approximately 75-mGy and a deficit of 60 mg was induced at 100 mGy. This confirms the effects projected and observed by Wanner and Edwards. Although the data do not demonstrate a clear dose-response relationship between the 75-mGy and 100-mGy groups, the data are statistically consistent with a dose-response effect because of the overlapping confidence intervals. The lack of a statistically significant observation is most likely related to the small difference in doses and the limited numbers of animals examined. There are several factors that can influence the brain weight of guinea pig pups, such as caging and housing conditions, the sex of the animal, and litter size. These should be taken into account for accurate analysis. Dam weight did not appear to have a significant effect. The confirmation of a micrencephalic effect induced x rays at doses of 75-mGy during this late embryonic stage of development is consistent with ...
The in situ assembly states of the glucose transport carrier protein in the plasma membrane and in the intracellular (microsomal) storage pool of rat adipocytes were assessed by studying radiation-induced inactivation of the D-glucose-sensitive cytochalasin B binding activities. High energy radiation inactivated the glucose-sensitive cytochalasin B binding of each of these membrane preparations by reducing the total number of the binding sites without affecting the dissociation constant. The reduction in total number of binding sites was analyzed as a function of radiation dose based on target theory, from which a radiation-sensitive mass (target size) was calculated. When the plasma membranes of insulin-treated adipocytes were used, a target size of approximately 58,000 daltons was obtained. For adipocyte microsomal membranes, we obtained target sizes of approximately 112,000 and 109,000 daltons prior to and after insulin treatment, respectively. In the case of ...
Conditions for radiationinduced grafting with butyl acrylate dispersed in water emulsion onto chrome-tanned pig skins have been worked out for #gamma#-rays and electron beam irradiations. The highest yield of grafting was observed at monomer concentration approximately 25% (w/w), dose equal to 25 kGy and dose rate not exceeding 10 MGy/h. At these conditions the yield of grafting attained a value approximately 25% and content of homopolymer in the leather amounted to 6%. The efficiency of monomer to polymer conversion decreases when the concentration of monomer in emulsion and dose rate increases. Yield of homopolymer is independent of the dose rate. An explanation of the observed relations has been proposed. The physical and used properties of grafted leathers were tested. Radiation processed leathers were found superior to samples finished by traditional methods. One has to point to better tolerance against chemical cleaning and reduced water ...
Total-dose irradiation seriously damages MOS devices and their circuit performance. Threshold voltage shifts, transconductance degradation and increase in off-state leakage current are generally observed for irradiated devices. These instabilities are essentially due to positive and/or negative charge trapping in SiO_2 and interface trap generation at the SiO_2/Si interface. Radiation hardening of CMOS VLSIs is to eliminate these trapping effects, and for this purpose, special considerations for fabrication processes and layout design are necessary. In this paper, basic mechanisms for radiation-induced charge trapping and related effects on MOS devices are reviewed. Also discussed are radiation-hardening technologies from both fabrication-process and layout-design viewpoints. Using these technologies, 1 #mu#m radiation-hard CMOS gate arrays have been successfully developed. Experimental data taken for 2k-gate test chips indicate that radiation hardness of these ...
We present changes in the p53 gene in a group of 70 thyroid tumours and 40 blood samples obtained from children from Belarus. Three thyroid tumours show a polymorphism in exon 6 (codon 213) and 5 tumours show a polymorphism in intron 6, 37 bp upstream to the 5'-end of exon 7. Only one patient has a mutation in exon 7 (codon 258) resulting in an amino acid substitution in the protein p53. The distribution of polymorphisms in the 40 blood samples was as follows: three patients had a polymorphism in exon 6 and two persons had a polymorphism in intron 6. One polymorphism in intron 6 was also found in the group of 30 healthy children from Belarus. The fact that the differences in the sequence in p53 found in the tumours was also seen in the blood of these patients demonstrates that they are polymorphisms not induced by radiation exposure. It is difficult to conclude, if the polymorphisms found by us could be associated with the predisposition to radiation-induced ...
The adverse effect of moisture diffusion on the properties of wood has been one of the main weaknesses of wood. Using a gamma irradiation method, wood-polymer composites have been produced which exhibit significant improvement in mechanical properties like compression, creep deformation and creep rupture particularly at high humidity. It has been thought that the impregnation of polymer into the wood has affected the moisture diffusion in the wood, so that its adverse effects on the mechanical properties has been reduced. In this report the apparent diffusion coefficients of a Ramin wood impregnated with varying amounts of polymethyl methacrylate (PMMA) were determined using a Fick's law approach. An initial linear relationship was found for impregnation of up to 70% PMMA, after which the diffusion coefficient levels off to a maximum value, for the three environmental relative humidity levels of 40, 60 and 90({plus minus}5)%. The phenomenon could be explained by means of a ...
The adverse effect of moisture diffusion on the properties of wood has been one of the main weaknesses of wood. Using a gamma irradiation method, wood-polymer composites have been produced which exhibit significant improvement in mechanical properties like compression, creep deformation and creep rupture particularly at high humidity. It has been thought that the impregnation of polymer into the wood has affected the moisture diffusion in the wood, so that its adverse effects on the mechanical properties has been reduced. In this report the apparent diffusion coefficients of a Ramin wood impregnated with varying amounts of polymethyl methacrylate (PMMA) were determined using a Fick's law approach. An initial linear relationship was found for impregnation of up to 70% PMMA, after which the diffusion coefficient levels off to a maximum value, for the three environmental relative humidity levels of 40, 60 and 90(#+-#5)%. The phenomenon could be explained by means of a cylindrical model ...
The electrical conductivity of Vitox-alumina (99.2%), Wesgo-alumina (99.9%) and AlN (99.6%) has been measured during and after irradiation with an experimental set-up which allows fusion relevant loading conditions. All irradiations were performed in high vacuum at 450 C using a 104 MeV {alpha}-particle beam with an applied DC electric field of 100 kV/m. In the high purity Vitox-alumina the in-situ and postirradiation bulk conductivities {sigma} and {sigma}{sub 0} show the highest irradiation induced electrical breakdown ever observed. The saturation level near 4 x 10{sup -2} ({Omega}m){sup -1}, reached already after 0.015 dpa (O-sublattice), is already above the critical value necessary to avoid MHD pressure drop with 10 {mu}m coatings in flowing liquid metal coolants. Under the same conditions no radiationinduced electrical degradation at all has been found in Wesgo-alumina and AlN. (orig.).
Thermoluminescence (TL) dosimetry was used to measure dose effects on the raw stock material of borosilicate container glass from different geographical locations. Effects were studied at times up to 60 days post-irradiation at doses from 0.15 to 20 Gy. The minimum detectable dose using this technique was estimated to be 0.15 Gy which is roughly equivalent to a 24 hr irradiation 1 cm from a 50 ng source of 60Co. Two peaks were identified in the TL glow curve, a relatively unstable peak around 125 C and a more stable peak around 225 C. Differences in TL glow curve shape and intensity were also observed for the glasses from different geographical origins. We investigate radiationinduced defects in glass to further develop the technique of intrinsic dosimetry - the measurement of the total absorbed dose received by the walls of a container holding radioactive material. Intrinsic dosimetry is intended to be used as an interrogation tool to provide ...
Chemical analyses were done on the abnormal hemoglobins of the five (101 x SEC)F_1 offspring of X- irradiated adult SEC mice to determine which hemoglobin genes were expressed in each hemoglobin variant. Three offspring of irradiated SEC males did not express either of the two kinds of #alpha#-chains normally found in all SEC mice. The deficient #alpha#-chain synthesis caused these mice to exhibit an #alpha#-thalassemia similar to human #alpha#-thalassemia. Scanning electron microscopy was used to show that many erythrocytes of mice with #alpha#-thalassemia have bizarre shapes; e.g. many erythrocytes appeared flattened or had thorny projections (acanthocytes). One mutant with a tandem duplication of a segment of chromosome 7 (site of locus determining #beta#-chain structure) produced twice as much SEC as 101 #beta#-chain polypeptides. One mutant that probably arose by non-disjunction of chromosome 7's in its unirradiated 101 mother and loss of chromosome 7 from the gamete of its ...
For an assessment of the future US spallation neutron source (SNS) target performance, radiationinduced hardening and microstructural evolution were investigated as a function of ion dose for EC316LN stainless steel. Irradiation was carried out using 3.5 MeV Fe{sup +}, 360 keV He{sup +}, and 180 keV H{sup +} simultaneous ion-beams at 200 deg. C to simulate the damage, He and H production in the SNS target vessel wall. At low dose (< 1 dpa), the predominant defects were black dots whose number density saturated rapidly within a few dpa. This was followed by the evolution of interstitial loops whose number density saturated below 15 dpa. Although He-bubbles were not visible, severely scalloped loops suggested that the implanted He/H atoms existed in the form of small clusters. Comparison with reported neutron irradiation data showed that hardening and ductility loss occurred mostly in the black dot regime (< 1 dpa), but that good ...
For an assessment of the future US spallation neutron source (SNS) target performance, radiationinduced hardening and microstructural evolution were investigated as a function of ion dose for EC316LN stainless steel. Irradiation was carried out using 3.5 MeV Fe"+, 360 keV He"+, and 180 keV H"+ simultaneous ion-beams at 200 deg. C to simulate the damage, He and H production in the SNS target vessel wall. At low dose (< 1 dpa), the predominant defects were black dots whose number density saturated rapidly within a few dpa. This was followed by the evolution of interstitial loops whose number density saturated below 15 dpa. Although He-bubbles were not visible, severely scalloped loops suggested that the implanted He/H atoms existed in the form of small clusters. Comparison with reported neutron irradiation data showed that hardening and ductility loss occurred mostly in the black dot regime (< 1 dpa), but that good ductility (>20% ...
The application of robotics for repair, refurbishing or dismantling of nuclear installations implies eventually severe radiation resistance requirements on embarked components and subsystems. This is particularly critical when optical sensing is considered. Optoelectronic components and optical fibers are indeed quite sensitive to radiation, and without special design are rapidly out-of-operation in such an environment. This paper reports the results of a series of #gamma# irradiation experiments on such devices, and identify their behavior under radiation. Test results show that carefully selected optical fibers can keep their radiationinduced attenuation lower than 0.3 dB/m even up to a total dose of 10 MGy. Temperature annealing can even lower this attenuation down to 0.1 dB/m. On the other hand, commercially available light emitting diodes and photodiodes present attenuations figures up to 15 dB, even after a gamma irradiation as low as ...
The D2 antidopaminergic drug Domperidone was evaluated singly and in combination with synthetic adrenocorticoid and an H2 antihistamine for its ability to reduce the acute emetic effects of /sup 60/Co whole-body radiation. Random-source adult male dogs were fasted 12 hours, fed a standard meal, injected 44 minutes later and irradiated 47 minutes after that. Four groups of dogs were radiated after drug injections as follows: saline (Con), domperidone (Dom), cimetidine + thiethylperazine (Cim+Thi), and dexamethasone + domperidone + cimetidine (Dex+Dom+Cim). Drug quantities for dogs represented 10 mg Dom, 10 mg Thi, 20 mg Dex, and 300 mg Cim for an average human (70 ka, 1.8 m2). Subjects were exposed on an up-down schedule to determine the radiation necessary to produce vomiting in 50% (ED50) of each group. Emesis onset times, offset times, and number of episodes were recorded. The ED50 of Dex+Dom+Cim was higher than Con. Dom produced more emetic episodes than Con or Dex+Dom+Cim. This ...
Aluminum nitride has been proposed as electrically insulating coating in connection with blankets made of vanadium alloys. Irradiations were performed with an applied DC electric field of 100 kV/m, using a 104 MeV {alpha}-particle beam. The dose achieved were 0.1 dpa at 300 C, 0.05 dpa at 400 C, and 0.06 dpa at 500 C. The out-of-beam conductivity {sigma}{sub 0} decreased at all temperatures employed during early stage of irradiation. Before 0.02 dpa had been reached, {sigma}{sub 0} dropped to low values of typically (2-4) x 10{sup -11} ({Omega} m){sup -1}. Although a moderate increase can be observed during further irradiation, {sigma}{sub 0} remained below the initial value of the unirradiated specimen for all temperatures. That is, there is no significant evidence for radiationinduced electrical degradation. The in-beam conductivity {sigma}, measured continuously during irradiation, also decreased by at least one order of magnitude. Relevant ...
The effects of gamma and e-beam irradiation on mechanical and structural properties of nylon 66 (Ny 66), nylon 6 (Ny 6) and poly(ethylene terephthalate) (PET) fabrics used in tyres were investigated. The untreated (greige), treated cords and calendered fabrics were irradiated at different doses. It is found that the effects of high energy irradiation on greige, treated cords and calendered fabrics are similar. No protective effect of compounds used in calendering was observed against radiation-induced oxidative degradation. The deterioration effect of gamma irradiation on mechanical properties is much higher than that of e-beam irradiation for all types of samples. Limiting viscosity numbers of both gamma and e-beam irradiated nylon 6 and nylon 66 cords were found to decrease with increasing dose. It is concluded that PET calendered fabric has higher resistance to ionizing radiation. Ny 6 and Ny 66 calendered fabrics are more sensitive even at low doses. Therefore, ...
Effect of radiation dose and carbon nanotubes (CNT) on the mechanical properties of standard Malaysian rubber (SMR) was investigated in this study. SMR nanocomposites containing 1-7 phr CNT were prepared using the solvent casting method and the nanocomposites were radiated at doses of 50-200 kGy. The change in mechanical properties, especially, tensile strength (Ts), elongation at break (Eb), hardness and tensile modulus at 100% elongation (M{sub 100}) were studied as a function of radiation dose. The structure and morphology of reinforced natural rubber was investigated by FESEM, TEM and AFM in order to gain further evidence on the radiation-induced crosslinking. It was found that the Ts, M{sub 100} and the hardness of the SMR/CNT nanocomposites significantly increased with radiation dose; the elongation at break exhibited an increase up to 100 kGy, and a downward trend thereafter. Results on gel fraction further confirmed the crosslinking of SMR/CNT ...
Ionising radiationinduces stable free radicals in chicken bones and in the shell of chicken eggs which can be detected, by the electrons spin resonance (ESR) technique, well beyond the shelf-life of the food and can be used for dosimetry. The method usually adopted to evaluate ``a posteriori`` the dose given during the ionising radiation treatment of food, is the dose additive method. To assess the dose, the ESR signal amplitude of the irradiated food (bone or egg shell in the present case) is measured and then the dose-effect relationship is obtained by re-irradiating the sample with some additive doses (usually of 1 kGy). The dose-effect curve is back-extrapolated and the initial given dose determined. At the Istituto Superiore di Sanita (ISS), Rome, Italy, a research programme was approved two years ago aimed to, (1) study new methodological approaches for ESR dose assessment, and (2) analyse the factors which may influence the ESR readout ...
Alloy HT-9 is being used for both duct and cladding applications in advanced liquid-metal reactor (LMR) experiments. This tempered martensitic steel was selected for use as an LMR core component material primarily because of its excellent resistance to radiation-induced swelling. Experiments conducted in the Fast Flux Test Facility (FFTF) at 410 degree C and exposures in the range of 150 to 175 displacements per atom (dpa) have shown that Ht-9 exhibits only a 0.2 to 0.3% increase in volume. Cold-worked austenitic steels exhibit volumetric increases of 20 to 30% at 410 degree C, Alloy HT-9 is being used for a series of fuel pin experiments in the FFTF, and these tests have achieved a burnup of 175 MWd/kg metal and a fluence of 25 x 10"2"2 n/cm"2 (E > 0.1 MeV) without fuel pin breach. The high confidence placed in HT-9 is based on a wide series of in- and ex-reactor experiments. Test results for these experiments are summarized in this paper.
Studies were conducted on mating behaviour and reproductive performance of a) Earias vittella (F.) males rendered sterile by exposing them to 300 Gy gamma rays and b) F_1 sterile males obtained by exposing parent male to 100 Gy gamma rays. For the study, males were allowed only one mating with a normal female. Results revealed that premating period, period in copula and per cent insects mating were not adversely affected in case of both types of sterile males and fecundity also remained unaffected. However, in both types of sterile males, incidence of spermatophore transfer without sperm was very large and such an occurrence (including reduced spermatophore transfer) was significantly higher in case of radiation sterilized males compared to the F_1 sterile males. Inability to produce and transfer spermatophore and/or sperm appeared to be a major cause behind the reduced mating competitiveness of both types of males. (author). 22 refs., 2 tabs.
The work scope of 'Biological Research for the Radiation Protection' had contained the research about ornithine decarboxylase and its controlling proteins, thioredoxin, peroxiredoxin, S-adenosymethionine decarboxylase, and glutamate decarboxylase 67KD effect on the cell death triggered ionizing radiation and H_2O_2(toxic agents). In this study, to elucidate the role of these proteins in the ionizing radiation (or H_2O_2)-induced apoptotic cell death, we utilized sensesed (or antisensed) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation and H_2O_2(or paraquat). We also investigated whether genisteine(or thiamine) may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation (may enhance the preventing effect radiation or paraquat-induced damage) because such compounds are able to potentiate the cell-killing or cell protecting effects. ...
The overall objective of this project has been to develop immunochemical methods to quantitate unique DNA base damages in order to facilitate studies on radiation-induced damage production and repair. Specifically, we have been using antibodies raised to damaged bases to quantitate unique lesions in model systems in order to evaluate their potential biological consequences. Our approach has been to synthesize modified nucleotides or nucleosides, conjugate them to protein carriers, and use the conjugates as immunogens in rabbits or to prepare monoclonal antibodies. We have been studying damages that are stable radiolysis products found in X-irradiated DNA and thus of potential biological consequence. Our aim is to build an in vitro and in vivo data base on the interactions between model DNA lesions and such cellular enzymes as DNA polymerases and repair endonucleases. Initial studies have focused on pyrimidine ring saturation products (thymine glycol.and ...
The overall objective of this project has been to develop immunochemical methods to quantitate unique DNA base damages in order to facilitate studies on radiation-induced damage production and repair. Specifically, we have been using antibodies raised to damaged bases to quantitate unique lesions in model systems in order to evaluate their potential biological consequences. Our approach has been to synthesize modified nucleotides or nucleosides, conjugate them to protein carriers, and use the conjugates as immunogens in rabbits or to prepare monoclonal antibodies. We have been studying damages that are stable radiolysis products found in X-irradiated DNA and thus of potential biological consequence. Our aim is to build an in vitro and in vivo data base on the interactions between model DNA lesions and such cellular enzymes as DNA polymerases and repair endonucleases. Initial studies have focused on pyrimidine ring saturation products (thymine glycol.and ...
The aim of this work was to study acute alterations of the enterohepatic recirculation (EHR) of bile acids 3 days after an 8-Gy radiation exposure in vivo in the rat by a washout technique. Using this technique in association with HPLC analysis, the EHR of the major individual bile acids was determined in control and irradiated animals. Ex vivo ileal taurocholate absorption was also studied in Ussing chambers. Major hepatic enzyme activities involved in bile acid synthesis were also measured. Measurements of bile acid intestinal content and intestinal absorption efficiency calculation from washout showed reduced intestinal absorption with significant differences from one bile acid to another: absorption of taurocholate and tauromuricholate was decreased, whereas absorption of the more hydrophobic taurochenodeoxycholate was increased, suggesting that intestinal passive diffusion was enhanced, whereas ileal active transport might be reduced. Basal hepatic secretion was increased only for ...
Iodized oil has been used as a contrast agent in lymphangiography. One of the commercially available compounds is Lipidol Ultra-fluid(LUF) which contains 38% iodine by weight. Nakakuma et al(1979) reported that LUF was selectively retained in the hypervascular hepatocellular carcinoma when injected directly into the ligated hepatic artery. Since that time, it has been widely utilized in the detection as well as the therapeutic attempts of hepatocellular carcinoma, where it has been mixed with chemotherapeutic agents or labeled with radioactive I-131. Like all significant advances, the mechanism of lipid retention within the hepatocellular carcinoma is not clearly understood, and also there is a lack of information about the biodistribution and kinetics of I-131 Lipiodol. The apparent safety of this technique require confirmation. The present study was aimed to assess the biodistribution and kinetics of intraarterially ...
Aim To better define the indications for adrenalectomy for adrenal metastasis we have analysed factors predicting survival in our institutional series. Methods A consecutive series of 30 patients undergoing adrenalectomy for metastasis (1996-2007), excluding patients with simultaneous ipsilateral renal cell carcinoma (RCC), was studied. Metastases were regarded as synchronous (6 mo), depending on the interval after primary surgery. Survival was calculated from time of adrenalectomy and factors influencing survival were identified. Results The tumour diagnoses were RCC n = 9, malignant melanoma n = 5, non-small-cell lung cancer n = 5, colorectal carcinoma n = 4, foregut carcinoid n = 2, adrenocortical carcinoma, breast cancer, hepatocellular carcinoma, urothelial c...
The photocytotoxic effect of hypericin (Hyp) targeted by two different delivery techniques, namely, liposomes and anti-hepatocyte specific antigen (anti-HSA) was investigated. Optical absorption and steady-state fluorescence were used to analyze the conjugation of Hyp with anti-HSA model and to evaluate the encapsulation capacity and drug release in a liposome model. Particle size and thermal analysis of the prepared liposomes were performed using laser-light scattering and differential scanning calorimetry (DSC), respectively. Viability study of HepG2 cells exposed to Hyp in the two delivery systems, in the dark and following visible light irradiation, was performed in comparison to free Hyp. The intracellular uptake and localization of Hyp in HepG2 cells were analyzed by means of spectro...
Polycyclic aromatic hydrocarbons (PAHs) are ubiquious in the environment both as natural products and as environmental contaminants. Among PAHs, phenanthrene (PH) that is ubiquitously distributed throughout the environment was subjected in this study. Although environmental distribution and metabolism of PH have been well reported, there are only a few studies examined the expression of mRNA and their functions on PH-induced toxicity. A new paradigm in toxicity screening, toxicogenomic technology represents a useful approach for evaluating the toxic properties of environmental pollutants. In this respect, we elicited the genes which were changed more than 2-fold by analysis of gene expression profiles in human hepatocellular carcinoma (HepG2) cells, exposed to PH by using human oligonucleo...
We evaluated the relation between the lipiodol accumulative pattern on CT 1 month after 1st Lp-TAE and the effect of Lp-TAE and recurrence of hepatocellular carcinoma (HCC) in 70 cases undergoing Lp-TAE twice. The lipiodol accumulative pattern on CT can be classified into four types (I: homogeneous, II: defect, III: inhomogeneous, IV: no or slight). In the type I, recurrence of the main tumor was 26.7%, daughter was 73.7%, suggesting a good effect of Lp-TAE. In the types II, III and IV, recurrence of the main tumor was seen in 66.7%, 83.3% and 83.3%, respectively, suggesting that the effect of Lp-TAE was worse according to the lipiodol accumulative pattern on CT. The lipiodol accumulative pattern on CT is useful for the detection of recurrence and assessment of the effect of Lp-TAE. (author).
The iodinated oil lipiodol is commonly used as a carrier for in situ delivery of drugs or radioactivity to hepatic tumors. Recently, we reported a new kit formulation for high-activity labeling of lipiodol with the {beta}-emitting radionuclide Re-188. Since the whole preparation involves different steps and complex manipulations of high-activity samples, we describe here an automated synthesis module that allows the easy preparation of sterile and pyrogen-free samples of Re-188 lipiodol ready to be administered to the patient. Important advantages include the possibility to incorporate high Re-188 activity into the lipiodol hydrophobic phase and a sharp reduction of radiation exposure of the operator assisting the labelling procedure. Application of this modular reaction system could be also extended to the preparation of other Re-188 radiopharmaceuticals and to compound labelled with different {beta}-emitting therapeutic radionuclides.
Population residing in the northern part of the Chelyabinsk oblast and the south eastern part of the Sverdlovsk oblast of Russia affected to accidental exposure since 1957. The territory (East Ural Radioactive Trace - EURT) was contaminated after explosion of container with highly radioactive wastes at the Mayak Production Association. Studies of health effects of exposure in the southern, head part of EURT are conducted in the Ural Research and Practical Center of Radiation Medicine (U.R.P.R.M.). In the 1990's U.R.P.C.R.M. formed a cohort of EURT within Chelyabinsk oblast (14,500 cases and 19,400 external controls). The cohort was followed in 1957-1987 and the results of the study are discussed by Crestinina et al. First results of study on exposure late health effects among rural population in the northern part of the EURT are presented in this paper. Firstly, or the period 1958-2000 a statistically significant increase in cancer mortality associated with accidental exposure ...
c-Jun N-terminal kinase 2 (JNK2) isoforms are transcribed from the jnk2 gene and are highly homologous with jnk1 and jnk3 transcriptional products....Full Text Available
Hypoxia causes abnormal neonatal pulmonary artery remodeling (PAR) and inhibition of alveolar development (IAD). Transforming growth factor (TGF)-β is an important regulator of lung development...Full Text Available
West Nile virus (WNV) is a mosquito-borne flavivirus that infects the central nervous system of humans and other animals. In this study, we found that C3H/HeN (C3H) mice exhibited a higher morbidity...Full Text Available
RNA interference (RNAi) is an effective tool for studying gene function in oocytes, but no studies have targeted somatic cells of primary cultured cumulus cell-oocyte complexes (COCs). This...Full Text Available
The management of CNS tumors is limited by the blood-brain barrier (BBB), a vascular interface that restricts the passage of most molecules from the blood into the brain. Here we show that phage particles...Full Text Available
A novel class of pyrrolidinyl-acetyleneic thieno[3,2-d]pyrimidines has been identified which potently inhibit the EGFR and ErbB-2 receptor tyrosine kinases. Synthetic modifications of the pyrrolidine carbamate moiety result in a range of effects on enzyme and cellular potency. In addition, the impact of the absolute stereochemical configuration on cellular potency and oral mouse pharmacokinetics is described.
Stromal cells from DBA/2 mouse bone marrow have been shown to be susceptible to cytotoxicity induced by several redox-active metabolites of benzene, including hydroquinone (HQ). Treatment with HQ also...Full Text Available
Stearoyl-coenzyme A desaturase (SCD) is the rate-limiting enzyme necessary for the biosynthesis of monounsaturated fatty acids. In this study, we investigated the regulation of mouse SCD1 by liver X...Full Text Available
Current information suggests that chemical carcinogenesis is a multistep process with one of the best studied models in this regard being the two-stage carcinogenesis system using mouse skin. The effects of several carcinogens and tumor promoters in various sequences of application were studied to examine the nature of the process. The actions of several tumor inhibitors were compared. (ACR)
We present a drawing package optimised for Feynman diagrams. These can be constructed interactively with a mouse-driven graphical interface or from a script file, more suitable to work with a diagram generator. It provides most features encountered in Feynman diagrams and allows to modify every part of a diagram after its creation. Special attention has been paid to obtain a high quality printout as easily as possible. This package is written in Tcl/Tk and in C. (orig.).
The past three years of work for the Air Force Office of Scientific Research has resulted in the development of a congenic mouse model of JP-8 jet fuel exposure, the role of substance P in the JP-8 jet fuel-induced lung injury process, and development of ...
Cordycepin has been shown to interfere with a myriad of molecular processes from RNA elongation to kinase activity, and prevents numerous inflammatory processes in animal models. Here we show in a mouse...Full Text Available
Two cellular DNA regions representing common domains for proviral DNA integration ( Mlvi -1 and Mlvi -2) have been identified in Moloney murine leukemia virus-induced rat thymic lymphomas. Cellular...Full Text Available
There is significant interest in using computed tomography (CT) for in vivo imaging applications in mouse models of disease. Most commercially available mouse x-ray CT scanners utilize a charge-coupled device (CCD) detector coupled via fibre optic taper to a phosphor screen. However, there has been little research to determine if this is the optimum detector for the specific task of in vivo mouse imaging. To investigate this issue, we have evaluated four detectors, including an amorphous selenium (a-Se) detector, an amorphous silicon (a-Si) detector with a gadolinium oxysulphide (GOS) screen, a CCD with a 3:1 fibre taper and a GOS screen, and a CCD with a 2:1 fibre taper and both GOS and thallium-doped caesium iodide (CsI:Tl) screens. The detectors were evaluated by measuring the modulation transfer function (MTF), noise power spectrum (NPS), detective quantum efficiency (DQE), stability over multiple exposures, and noise ...
Environmental and occupational exposures to heavy metals such as methylmercury (MeHg) and cadmium (Cd) pose significant health risks to humans, including neurotoxicity. The underlying mechanisms of...Full Text Available
4.5S RNA is a group of RNAs 90 to 94 nucleotides long (length polymorphism due to a varying number of UMP residues at the 3' end) that form hydrogen bonds with poly(A)-terminated RNAs isolated from...Full Text Available
The present investigation was aimed to assess the usefulness of biliary agents scintigraphy in the diagnosis of hepatocellular carcinoma (HCC) and to ascertain the relationship between the uptake of these agents and the degree of HCC differentiation. Forty-four patients with this hepatic cancer were included in the study. Liver scans were performed 20 min and 3 hr after the administration of 99mTc diisopropyliminodiacetic acid (DISIDA). DISIDA scintigraphy could not be assessed in six cases. In 16 (42%) out of the remaining 38 patients, the tumor exhibited equal or greater radioactivity uptake than the surrounding liver. In six out of these 16 patients, tumor uptake was apparent in the early and delayed hepatic scans, while in the other ten subjects radioactivity uptake by the HCC could only be detected in the 3-hr delayed scans. In the remaining 22 patients, HCC appeared as a cold area. Tumor location by this technique did not differ from that observed by ...
PURPOSE: Hepatocellular carcinoma (HCC) is a highly virulent malignancy with no effective treatment thus requiring innovative and effective targeted therapies. The oncogene Astrocyte elevated gene-1 (AEG-1) plays a seminal role in hepatocarcinogenesis and profoundly downregulates insulin-like growth factor binding protein-7 (IGFBP7). The present study focuses on analyzing potential tumor suppressor functions of IGFBP7 in HCC and the relevance of IGFBP7 downregulation in mediating AEG-1 function.EXPERIMENTAL DESIGN: IGFBP7 expression was detected by immunohistochemistry in HCC tissue microarray and real-time PCR and ELISA in human HCC cell lines. Dual Fluorescence in situ hybridization was performed to detect loss of heterozygosity at IGFBP7 locus. Stable IGFBP7-overexpressing clones were established in the background of AEG-1-overexpressing human HCC cells and were analyzed for in vitro proliferation and senescence and in vivo tumorigenesis and ...
Hemodynamic characteristics were studied by using in vivo vascular imaging techniques in 17 resected early stage hepatocellular carcinoma (e-HCC) by comparing them with 49 resected advanced HCCs (ad-HCC) less than 3 cm in diameter. In this study, e-HCC was defined as the nodule being uniformly composed of well-differentiated HCC or adenomatous hyperplastic nodule containing well-differentiated HCC foci within the nodule. In vivo vascular imaging techniques are as follows; US angiography with intraarterial CO{sub 2} microbubbles were performed to assess the tumor arterial vascularity, and CT during arterial portography (CTAP) was performed to assess the portal perfusion within the nodule. Of 17 e-HCC nodules 5 were hypervascular, 5 were isovascular, 4 were hypovascular, and 3 were vascular spot in hypovascular pattern in contrast to 49 ad-HCC nodules, 43 of which were hypervascular and 6 were isovascular. Of 14 e-HCCs, 9 nodules showed perfusion defect and 5 did not ...
Inferior vena cava (IVC) obstruction is a well-described clinical entity. Most IVC obstructions from malignant neoplasms are a direct result of tumor compression [Oviedo J, Cerda S. Vascular invasion by hepatocellular carcinoma. Arch Pathol Lab Med 2001;125: 454-5; Furui S, Sawada S, et al. Gianturco stent placement in malignant caval obstruction: analysis of factors for predicting the outcome. Radiology 1995;195:147-52; Fletcher WS, Lakin PC, et al. Results of treatment of inferior vena cava syndrome with expandable metallic stents. Arch Surg 1998;133:935-8]. The symptoms of IVC obstruction include progressive ascites, scrotal edema and lower body edema. These constellations of symptoms are described as IVC syndrome and are devastating to a patient with end-stage cancer. We describe a palliative therapy utilizing Luminexx nitinol self-expanding stents to treat intracaval hepatoma thrombus obstructing the IVC. The procedure is rapidly performed, technically ...
Lipiodol CT is a important modality for the diagnosis of hepatocellular carcinoma and compared is usually performed at 2-3 week after Lipiodol injection. Therefore, we assessed and the diagnostic value and merits of immediate CT after chemoembolization from there of 2-3 week delayed Lipiodol CT. Thirty three cases of chemoembolization which were performed both immediate CT after chemoembolization and 2-3 week delayed Lipiodol CT were reviewed retrospectively. They were divided into four grades according to pattern of lipiodol uptake by three radiologists. The diagnostic value of immediate Lipiodol CT was compared to delayed Lipiodol CT. Grade 0 was two cases(3.0%) and Grade 1 was seven cases(21.2%). In the cases of Grade 2(23/33, 69.7%), tumor uptake could be dishing wished from parenchymal uptake of Lipiodol by its density and pattern, Tumor uptake showed dense and homogeneous pattern, but parenchymal uptake revealed less dense and hepatogram-like wedge shaped ...
To assess whether ring enhancements of liver metastases on Mn-DPDP enhanced, early MR images were well visualized on delayed images, as compared with those of hepatocellular carcinomas (HCC), and to investigate the detection accuracy and conspicuity of each tumor. Twenty patients with liver metastases and 15 with HCC were studied by Mn-DPDP enhanced, T1-weighted MR images. Peripheral ring enhancement and conspicuity were investigated. Differences in detection accuracy and frequency of ring enhancement in liver metastases and HCC were assessed. In liver metastases (n= 69), 44 cases (63.8%) without ring enhancement and 25 (36.2%) with were noted on early images. Sixteen cases (23.2%) without ring enhancement, 38 (55.1%) with ring enhancement similar to the early images, and 15 (21.7%) with prominent ring enhancement were noted on delayed images. In HCC (n=37), 36 cases (97.3%) without ring enhancement and 1 case (2.7%) with were noted on early images. There was no ...
Although the radioisotope liver scan has primarily been of use in the detection of the intra-hepatic space occupying lesions, there has been an increasing awareness of its use in evaluation of liver function. In this study, the degree of hepatomegaly, changes in shape and mottling radiodensity on each lobe and splenic visualization in the liver scans done with colloidal radiogold were numerically expressed as scores under the arbitrary standard in 210 patients with liver cirrhosis. The clinical value of this scoring system was studied with special regards to the correlation between the radiogold hepatic uptake half time and conventional liver function tests. Following were the results; 1) The normal scan appeared in 6.7% of 210 patients with liver cirrhosis. 2) The colloidal radiogold hepatic uptake half time was abnormally and progressively prolonged in parallel to severity of hepatocellular dysfunction. The mean hepatic uptake half time in cirrhosis showing ...
Mutations in the mouse formin (Fmn) gene, formerly known as the limb deformity (ld) gene, give rise to recessively inherited limb deformities and renal malformations or aplasia. The Fmn gene encodes many differentially processed transcripts that are expressed in both adult and embryonic tissues. To study the genomic organization of the Fmn locus, we have used Fmn probes to isolate and characterize genomic clones spanning 500 kb. Our analysis of these clones shows that the Fmn gene is composed of at least 24 exons and spans 400 kb. We have identified two novel exons that are expressed in the developing embryonic limb bud as well as adult tissues such as brain and kidney. We have also used a microsatellite polymorphism from within the Fmn gene to map it genetically to a 2.2-cM interval between D2Mit58 and D2Mit103. 36 refs., 6 figs., 1 tab.
The purpose was to study the toxicity of drugs known to generate free radicals on isolated pancreatic islets. The accumulattion of "8"6Rb"+ by mouse pancreatic islets was measured in vitro. Exposing the islets to 6-hydroxydopamine, minhydrin, or phenazine methosulphate + NADH inhibited the Rb"+ uptake, whereas paraquat or acetylphenylhydrazine had no effect. This effect of 6-hydroxydopamine was prevented by either of the hydroxyl radical scavengers, sodium benzoate and mannitol, but not by the non-scavenger,urea; ninhydrin was partially protected against by mannitol but not by benzoate. Protection against 6-hydroxydopamine was also afforded by D-glucose but not by L-glucose or 3-O-methyl-D-glucose; none of the sugars protected against ninhydrin. In damaging islet beta-cells and in being protected against by D-glucose, 6-hydroxydopamine closely resembles the diabetogenic drug, alloxan. It is suggested that protection against alloxan may involve both glucose ...
A rickettsia related to but distinct from the spotted fever agent, Rickettsia rickettsii, has been detected in 167 (18.9%) of 884 Rhipicephalus sanguineus taken off dogs in central and northern Mississippi. The organisms could readily be isolated in male meadow voles (Microtus pennsylvanicus), where it produced massive infections in the tissues of tunica vaginalis. It was practically nonpathogenic for male guinea pigs, although inoculation of these animals with infected tunica vaginalis of voles afforded in 30 of 38 instances solid immunity to challenge with virulent R. rickettsii. The Rhipicephalus rickettsia grew well in monolayers of chicken embryo fibroblast, Vero, mouse L, and HeLa cells. Cytopathogenic effects were minimal unless large concentrations of rickettsiae were used as inocula. It also could be established in embryonated hen eggs but only after injection of massive doses of L cell-propagated organisms. Serological tests (complement fixation, ...
Results reported are for single dose exposures and refer to "6"0Co-#gamma#-irradiation. The RBE determined by V79 cell survival and based on the Do ratio was found to be 1.70#+-#0.4 ranging from 1.5 to 1.8. In the case of the regeneration of mouse jejunal crypts the RBE was calculated at ten cell curvival and was found to be 1.68. The maximum acute mouse skin reaction at a skin score of 2.0 was found to be 2.1 while the average skin reaction was 1.7. Growth retardation of Vicia faba bean roots measured at the level of 50% indicated an average RBE of 3.0 and a range of 2.7 to 3.7. The OER obtained for V79 cell survival was found to be 1.7 to 1.8. Comparison is made with the RBE and OER measurements for the neutron facilities at Clatterbridge, Fermilab and Louvain-la-Neuve which produce neutrons by the same nuclear reaction and whose physical specifications closely resemeble those of the Faure neutrons. This comparison indicates that the Faure ...
The studies reported here used genetic differences in susceptibility of C57BL/6N and C3H/HeN mice and exacerbation of the disease by nitrogen dioxide (NO/sub 2/) as tools in assessing the role of early host responses in the pathogenesis of MRM. The two strains did not differ in susceptibility to infection, but C3H/HeN mice were more susceptible to and had increased severity of lung lesions 14 days after intranasal inoculation as determined by 50% biological endpoints and morphometric analysis of tissues. Exposure to NO/sub 2/ for 4 hours prior to exposure to infectious aerosols exacerbated murine respiratory mycoplasmosis (MRM) by 7 days after exposure in both mouse strains. NO/sub 2/ appeared to affect host lung defense mechanisms responsible for limiting mycoplasmal growth in the lungs. The NO/sub 2/ exposure concentration required for this effect varied with the genetic background of the host, the dose of mycoplasmas administered, and the endpoint measured. ...
Goosecoid is a homeobox gene first isolated from a Xenopus dorsal lip cDNA library. Homologous genes have been isolated from mouse, zebrafish, and chick. In all species examined, the gene is expressed and plays an important role during the process of gastrulation in early embryonic development. The authors report here the cloning of the human goosecoid (GSC) from a genomic library and the sequence of its encoded protein. The genomic organization and protein sequence of the human gene are highly conserved with respect to those of its Xenopus and mouse counterparts: all three genes consist of three exons, with conserved exon-intron boundaries. The sequence of the homeo-domain is 100% conserved in most vertebrates. Using somatic cell hybrid and chromosomal in situ hybridization, the gene was mapped to chromosome 14q32.1. 30 refs., 3 figs., 2 tabs.
Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A total of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of ...
The endothelin-B (ETB) receptor is a G-protein-coupled receptor that binds endothelin ligands and is essential for the development of epidermal melanocytes and enteric neurons. Recent reports indicate that ETB is localized to nuclei in cardiac ventricular myocytes, although it has been thought that ETB is localized mainly on the plasma membrane. It remains unknown, however, whether this unique distribution of ETB occurs in other tissues. To elucidate the subcellular distribution of ETB in the intestine, we performed immunofluorescence of ETB in mouse intestine using a specific antibody. ETB-like immunoreactivity was detected in both the mucosal and muscle layers. In the mucosal layer, villous epithelial cells, stromal cells of the lamina propria, and cryptic cells were immunostained. Subcellularly, ETB is localized mainly to the nuclei of villous epithelial cells. In the muscle layer, immunoreactivity of ETB was localized to the myenteric plexus. These findings ...
Water and mud samples were collected from canals and rivers which were adjacent to outlets discharging warm water of 3 power plants in Berlin. Downstream samples from 1 bathing resort were also collected. Free living amoebae were isolated from 138 water and 69 mud samples. From these respectively 156 and 73 strains could be cultured and were administered intranasally to mice for pathogenicity tests. Two Acanthamoeba strains from water and 7 from mud could be reisolated from mouse brain and or lungs, although no pathological disorders could be observed. Five Naegleria strains were negative in mouse inoculation tests. Four Acanthamoeba strains which were positive in mice were cultured at + 45 degrees C; no cytopathogenic effects were observed in tissue cultures. Acanthamoeba infective for mice could also be isolated from samples at low water temperatures. Further investigations have to show, whether changes in virulence of amoebic strains are of ...
The effects of mouse epidermal growth factor (EGF) on bone formation and resorption were examined in male mice. EGF administration (2-200 ng.g-1.day-1 ip for 7 days) induced a dose-dependent rise in plasma EGF levels that remained within physiological range. Histomorphometric analysis of caudal vertebrae showed that EGF (20 and 200 ng.g-1.day-1) reduced the endosteal matrix and mineral appositional rates after 5 days of treatment as measured by double (3H)proline labeling and double tetracycline labeling, respectively. This effect was transitory and was not observed after 7 days of EGF administration. EGF administered for 7 days induced a dose-dependent increase in the periosteal osteoblastic and tetracycline double-labeled surfaces. At high dosage (200 ng.g-1.day-1) EGF administration increased the osteoclastic surface and the number of acid phosphatase-stained osteoclasts, although plasma calcium remained normal. The results show that EGF administration at ...
Thymic epithelial cells (TECs) constitute a major component of the thymic stroma which provides a microenvironment critical for developing thymocytes. We have previously demonstrated that doxycycline (Dox), a tetracycline derivative, enhances the proliferation of the mouse thymic epithelial cell line 1 (MTEC1) via MAPK/ERK signal pathway. Herein we provide evidence that Dox also has profound impact on the cytokine production by MTEC1. Specifically, the expression of IL-6 and GM-CSF, both at mRNA and protein levels, was found to be increased in a time- and dose-dependent manner with the addition of Dox. Western blotting analysis revealed that treatment with Dox-induced phosphorylation of the p65 subunit of NF-kB and ERK. Notably, Dox-induced up-regulation of IL-6 and GM-CSF was largely abol...
WR-2721 (S-2-(3-aminopropylamino)ethylphosphorothioic acid) has been demonstrated to be cytotoxic to stem spermatogonia in the mouse. Five and 10 injections of 300 mg/kg killed sufficient numbers of stem cells to reduce sperm production 56 days after treatment by 16 and 43%, respectively. Single injections of 300 or 400 mg/kg of WR-2721 given 15 min after irradiation produced negligible toxicity to stem cells as measured by counts of repopulated tubules; 600 mg/kg reduced stem cell survival by 47%. Four daily injections of 300 mg/kg given 4, 3, 2, and 1 days prior to irradiation reduced stem cell survival by about 60%. The cytotoxic effects of WR-2721 on testicular stem cells at least partially explains the reduced protection factors observed in the testis with low doses of radiation and during fractionated treatments involving multiple injections of drug.
The photobiology of mouse melanocyte lines with different pigment genotypes was studied by measuring colony-forming ability after irradiation. The cell lines were wild-type black (melan-a) and the mutants brown (melan-b) and albino (melan-c). Four lamps emitting various UV wavelengths were used. These were germicidal (UVC, 200-280 nm), 82.3% output at 254 nm, TL01 (UVB, 280-320 nm), 64.2% at 310-311 nm, FS20, broadband with peak output at 312 nm and Alisun-S (UVA, 320-400 nm), broadband with peak output at 350-354 nm. Appropriate filtration reduced the contaminating UVC to nonlethal levels for the longer waverange lamps. It is clear from these studies that, in pigment cells, monochromatic results cannot predict polychromatic responses and that cell death from solar irradiations is a complex phenomenon that depends on more than DNA damage. (author).
Lethal yellow (A{sup y}) is a mutation at the mouse agouti locus in chromosome 2 that causes a number of dominant pleiotropic effects, including a completely yellow coat color, obesity, an insulin-resistant type II diabetic condition, and an increased propensity to develop a variety of spontaneous and induced tumors. Additionally, homozygosity for A{sup y} results in preimplantation lethality, which terminates development by the blastocyst stage. The A{sup y} mutation is the result of a 170-kb deletion that removes all but the promoter and noncoding first exon of another gene called Raly, which lies in the same transcriptional orientation as agouti and maps 280 kb proximal to the 3{prime} end of the agouti gene. The authors present a model for the structure of the A{sub y} allele that can explain the dominant pleiotropic effects associated with this mutation, as well as the recessive lethality, which is unrelated to the agouti gene.
The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of /sup 3/H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes.
The usefulness of the mouse, rat, and Syrian golden hamster as experimental models for studies of the development of respiratory tract cancer is considered. Three different application methods for examining the effects of environmental chemicals on the respiratory tract in these species are discussed: implantation, intratracheal instillation, and inhalation. The results of various investigations are presented to demonstrate that each particular method has both advantages and disadvantages. The techniques are also considered in comparison with the human situation and in the light of obtaining the most valid data for extrapolation to man. Brief attention is paid to the relevance to respiratory tract carcinogenesis of more recently developed organ and cell culture systems.
Hyaluronate (HA) distribution patterns were examined in the cranial mesenchyme underlying the mesencephalic neural folds of mouse embryos maintained in roller tube culture. Using standard image-processing techniques, the digitized images of Alcian blue-stained or 3H-glucosamine-labeled sections digested with an enzyme specific for HA, were subtracted from adjacent, undigested sections. The resultant difference picture images (DPI) accurately depicted the distribution of stained or labeled HA within the cranial mesenchyme. 3H-glucosamine-labeled HA was distributed uniformly throughout the cranial mesenchyme as 12, 18, and 24 hr of culture. By contrast, the mesenchyme was uniformly stained with Alcian blue at 12 hr, but stain intensity decreased in the central regions of the mesenchyme at 18 and 24 hr. HA distribution patterns were also examined in the cranial mesenchyme of embryos cultured in the presence of diazo-oxo-norleucine (DON), a glutamine analogue that ...
We irradiated proton beams on the ears of rabbits and the Harding-Passey mouse melanoma and observed their morphological change. We used 52 MeV proton beams from the INS-FM cyclotron. We adjusted the energy of the proton beams to be at the plateau part of the Bragg curve, at the half-way point of the Bragg peak, and at the Bragg peak. The amount of radiation was 5000rad in each case. The Harding-Passey mouse melanoma was transplanted into the subcutan of a three week old mouse. In this experiment, we used tumors, the diameter of which grew up to 1.5-2cm in 2-3 weeks after the transplantation. Using the jroscope, we observed both lightly and severely damaged cells. Using proton irradiation with the Bragg peak located at depth of 1mm in the rabbit's ears, we studied the change in the tissue. Irradiated epidermis fell off and was eroded because of radiation damage, but the rear surface of the rabbit's ears ...
BackgroundIn recent years, near-infrared fluorescence (NIRF)-labeled iron nanoparticles have been synthesized and applied in a number of applications, including the labeling of human cells for monitoring the engraftment process, imaging tumors, sensoring the in vivo molecular environment surrounding nanoparticles and tracing their in vivo biodistribution. These studies demonstrate that NIRF-labeled iron nanoparticles provide an efficient probe for cell labeling. Furthermore, the in vivo imaging studies show excellent performance of the NIR fluorophores. However, there is a limited selection of NIRF-labeled iron nanoparticles with an optimal wavelength for imaging around 800 nm, where tissue autofluorescence is minimal. Therefore, it is necessary to develop additional alternative NIRF-labeled iron nanoparticles for application in this area.ResultsThis study manufactured 12-nm DMSA-coated Fe3O4 nanoparticles labeled with a near-infrared fluorophore, IRDye800CW (excitation/emission, ...
A human cholangiocarcinoma, Ch-1, serially transplanted to nude mice was used for experimental chemotherapy, radiotherapy, and conbination chemoradiotherapy. In the group of chemotherapy with single drug, Mitomycin C (MMC) revealed greater effectiveness than Adriamycin in terms of tumor regression, histological findings, and minor side effects. MMC and radiotherapy by Linac X-ray showed exponential linear dose response curve against tumor weight. Their effects were equivalent at doses of MMC 1 mg/kg and radiation 1,000 rads/mouse in the changes of tumor weight and of histological findings which were similar to each other. Combination chemoradiotherapy showed the synergistic action when the radiation (500 rads/mouse) was performed before MMC (0.5 mg/kg) administration, whereas only the additive effect was observed when the sequence was reversed. The cell kinetic analysis was performed by the impulse cytophotometry, "3H-thymidine uptake labeling ...
Several short-lived, high-energy beta emitters are being proposed as the radionuclide components for molecular-targeted potential cancer therapeutic agents. The laboratory mice used to determine the efficacy of these new agents have organs that are relatively small compared to the ranges of these high-energy particles. The dosimetry model developed by Hui et al. was extended to provide realistic beta-dose estimates for organs in mice that received therapeutic radiopharmaceuticals containing 90Y, 188Re, 166Ho, 149Pm, 64Cu, and 177 Lu. Major organs in this model included the liver, spleen, kidneys, lungs, heart, stomach, small and large bowel, thyroid, pancreas, bone, marrow, carcass, and a 0.025-g tumor. The study as reported in this paper verifies their results for 90Y and extends them by using their organ geometry factors combined with newly calculated organ self-absorbed fractions from PEREGRINE and MCNP. PEREGRINE and MCNP agree to within 8% for the worst-case organ with average ...
A quantitative comparison of tissue distribution and excretion of an orally administered sublethal dose of [3H]diacetoxyscirpenol (anguidine) was made in rats and mice 90 min, 24 hr, and 7 days after treatment. Total recoveries of 95-100% were obtained. Approximately 90% of the dose was excreted in urine and feces during the first 24 hr with a feces:urine ratio of about 1:4.5 in both species. Carcass and tissue radioactivity dropped rapidly during the first 24 hr but remained relatively constant at low, but detectable, levels over the course of the experiment. Few substantive interspecies differences were noted in tissue distribution. At 90 min the highest percentage of dose was in tissues involved in sequestering diacetoxyscirpenol because of high body water/lipid content or the absorption, metabolism, or excretion of the toxin. The rank order of these tissues was generally stable over the course of the experiment. When data were expressed as specific radioactivity instead, the ...
Medical imaging using single gamma-ray-emitting radionuclides typically makes use of parallel hole collimators or pinholes in order to achieve good spatial resolution. However, a tradeoff in sensitivity is inherent in the use of a collimator, and modern preclinical single photon emission computed tomography (SPECT) systems detect a very small fraction of emitted gamma rays, often less than 0.1%. A system for small animal SPECT imaging which uses no collimators could potentially achieve very high sensitivity-several tens of percent-with reasonably sized detectors. This would allow two significant improvements in preclinical studies: images could be obtained more rapidly, allowing higher throughput for screening applications, or for dynamic processes to be observed with very good time resolution; and images could be obtained with less radioactive tracer, making possible the in vivo imaging of low-capacity receptor systems, aiding research into new tracer compounds, and reducing the cost ...
Two most important causes of portal hypertension are cirrhosis of liver and non-cirrhotic portal fibrosis (NCPF). The purpose of this study was to assess the scintigraphic appearances of "9"9"mTc sulfur colloid liver scan in differentiating liver cirrhosis from NCPF. Materials and Methods: Retrospective analysis records of 146 patients (91 male and 55 female) with diffuse hepatocellular disease was done for liver size, liver uptake, spleen size, spleen uptake, colloid shift to bone marrow and lungs. Results: Cirrhotic livers showed patchy and lower uptake than NCPF (59% vs. 20%, P-value 0.041). Spleen size was significantly increased in NCPF compared to cirrhosis (100% vs. 67%, P-value 0.0137). Significant colloid shift to bone marrow was noted in cirrhosis (84% vs. 7%, P-value<0.0001). Conclusion: "9"9"mTc sulfur colloid liver scan is a non-invasive procedure having a useful adjunctive role in clinical differentiation of cirrhosis from NCPF. (author)
Staging bone scans or skeletal surveys were obtained of 97 patients with endometrial carcinoma. Of the 77 patients with Stage I or II disease, no metastases were identified at staging. Three patients in the entire series demonstrated bony metastases; all of these metastases were detectable by radionuclide bone scan and radiographic bone survey. Eighty-nine patients were examined with radionuclide liver/spleen scanning at the time of staging. Four of the 89 initial scans were interpreted as demonstrating hepatocellular disease, and all four patients had abnormal liver function studies. Only one patient demonstrated a possible hepatic metastasis at initial diagnosis. This patient also had abnormal liver function studies. Based on these results, bone surveys and radionuclide bone scans are not indicated as screening procedures in endometrial carcinoma. It is suggested that screening for liver metastases in patients with endometrial carcinoma is not warranted in ...
SommarioScopo In questo studio riportiamo i dati relativi all'ablazione percutanea con Radiofrequenza (RF) di HCC e trombosi neoplastica dei vasi portali. Pazienti e metodi Dieci pazienti (pz) cirrotici, 7 maschi e 3 femmine, eta media 68 anni, con 10 noduli di HCC e trombosi neoplastica dei vasi portali sono stati sottoposti ad ablazione percutanea con RF del trombo neoplastico e dell'HCC. La RF veniva ritenuta efficace quando alla TC con mdc si osservava la necrosi completa dell'HCC e al Color Doppler si osservava la ricanalizzazione completa dei vasi portali. Risultati La necrosi completa dell'HCC e la ricanalizzazione completa dei vasi portali si osservava in 7 (70%) dei 10 pazienti. Nei rimanenti 3 (30%) la necrosi dell'HCC e la ricanalizzazione dei vasi portali non risultavano comple...
Proteomic changes in proteins secreted by human hepatocellular carcinomas (HepG2) cells exposed to butyl benzyl phthalate (BBP) were evaluated. HepG2 cells were treated with three different concentrations of BBP (0, 10, or 25 ?M) for 24 or 48 h. Following incubation, the cells were subjected to proteomic analysis using two different pI ranges (4-7 and 6-9) and large-size two-dimensional gel electrophoresis. Results showed resolution of a total of 2776 protein spots. Of these, 29, including 19 upregulated and 10 downregulated proteins, were identified by electrospray ionization-mass spectrometry-mass spectrometry (ESI-MS/MS). Among these, the identities of cystatin C, Rho guanine nucleotide dissociation inhibitor, gelsolin, DEK protein, Raf kinase inhibitory protein, triose phosphate ...
Summary.? It is widely believed that hepatocellular cancer (HCC), especially HBV associated HCC, is highly resistant to chemotherapy. To investigate the molecular influence of HBx protein on multidrug resistance (MDR) in HCC and the potential role of the NF-?B pathway in this process. We established HBx-expressing cells by liposome-mediated transfection of the HBx into the HepG2 cell line. We found that HBx expression in HCC cells induces drug resistance against multiple drugs, a significantly lower apoptosis ratio in HepG2-HBx and HepG2.2.15 cells, compared with HepG2 and HepG2-3.1 cells (P?HCC cells were downregulated by IMD-0354 treatment, which is the NF-?B pathway inhibitor. Taken together, these results suggest that HBx protein might be one of the causes for the occurrence of MDR in HCC, and the NF-?B pathway might be involved in this change. PMID:21914061
Forty resected cases of intrahepatic cholangiocarcinoma were classified into four types according to the gross appearance; type I: mass forming type (n=8), type II: mass forming with periductal infiltrating type (n=20), type III: periductal infiltrating type (n=9) and type IV: intraductal growth type (n=3). Diagnostic features of these four types were studied. Peripheral enhancement was a common angiographic feature and tumor stains were recognized in 88%, 20%, 0%, 33%, respectively. Angiography and dynamic computed tomography (D-CT) were useful in differential diagnosis with hepatocellular carcinoma. Accuracy rate in diagnosis of portal vein involvement by angiography and D-CT was 82% and 91%, respectively. MRI was more useful in tumor detection than D-CT in cases with attenuation difference, in 55% of type II and in 75% of type III. Increase of arterial involvement, biliary tract involvement and portal vein involvement, incidence of lymph nodes metastases became ...
Persistent hepatitis C virus (HCV) infection affects 170 million people worldwide. Acute HCV infection is often asymptomatic, but many infected individuals develop persistent infections that may lead to development of end-stage liver diseases, including liver cirrhosis and hepatocellular carcinoma. Thus, an HCV vaccine that could significantly lower the chronicity rate would have a major impact on the disease burden. Unfortunately, HCV is a highly mutable virus, and escape mutations can undermine vaccine-induced virus-specific immunity. Also, HCV exists as multiple genotypes, and so genotype-specific vaccines might be required to achieve broad protection. Finally, vaccine development has been hampered by the lack of a small animal model and cell culture systems, but these are currently being established. Despite these obstacles, several vaccine candidates tested in the chimpanzee HCV model have shown some encouraging results.
No-carrier-added astatine radionuclides produced in the {sup 7}Li-irradiated lead matrix were separated from bulk lead nitrate target by complexing At with insulin, followed by dialysis. The method offers simultaneous separation of At from lead as well as its complexation with insulin. The At-insulin complex might be a potential radiopharmaceutical in the treatment of hepatocellular carcinoma. The stability of At-insulin complex was checked by dialysis against deionized water and Ringer lactate (RL) solution. It has been found that the half-life of At-insulin complex is about {approx}12 h, when dialyzed against deionized water and is only 6 h, when dialyzed against RL solution having the same composition as blood serum. The 6 h half-life of this Insulin-At complex is perfect for killing cancer cells from external cell surfaces as the half-life of internalization of insulin molecule inside the cell is 7-12 h.
No-carrier-added astatine radionuclides produced in the "7Li-irradiated lead matrix were separated from bulk lead nitrate target by complexing At with insulin, followed by dialysis. The method offers simultaneous separation of At from lead as well as its complexation with insulin. The At-insulin complex might be a potential radiopharmaceutical in the treatment of hepatocellular carcinoma. The stability of At-insulin complex was checked by dialysis against deionized water and Ringer lactate (RL) solution. It has been found that the half-life of At-insulin complex is about #approx#12 h, when dialyzed against deionized water and is only 6 h, when dialyzed against RL solution having the same composition as blood serum. The 6 h half-life of this Insulin-At complex is perfect for killing cancer cells from external cell surfaces as the half-life of internalization of insulin molecule inside the cell is 7-12 h.
Summary The purpose of this study was to evaluate the efficacy of postoperative adjuvant chemotherapy with FOLFOX regimen on the outcome after LT for HCC patients who did not meet the Milan criteria. Ninety-five consecutive HCC patients with liver cirrhosis undergoing LT were enrolled. Fifty-eight who did not meet the Milan criteria were randomized to open-label treatment with or without adjuvant chemotherapy after LT (n?=?29/group). The FOLFOX chemotherapy protocol comprised 3-week cycles of oxaliplatin 100?mg/m2 on day 1, leucovorin (calcium folinate, CF) 200?mg/m2 on day 1 followed by 3-day, and 5-fluorouracil (5-FU) 2000?mg/m2 as a 48-h continuous infusion, for up to six courses in the 1st year after transplantation. Median survival was extended by 4.57?months by combination chemothera...
Purpose: To evaluate contrast-enhanced CT scan in the diagnosis of intrahepatic cholangiocarcinoma by correlating the CT appearance with pathologic specimens. Materials and methods: Twenty-eight patients with pathologically proven intrahepatic cholangiocarcinoma were examined. Unenhanced abdominal CT study were performed in 28 patients; conventional contrast-enhanced CT in 27 patients. Enhanced CT scan including fast injection, fast scan and delayed scan at the largest section of the lesion was done in 7 patients. Contiguous 10 mm CT scans of the surgical specimens were also obtained in 8 patients. The preoperative and specimen CT scans in these 8 patients were compared with the corresponding pathological sections. A total of 103 areas of the pathological sections was compared with the CT appearances. Results: All lesions contained areas of delayed contrast enhancement and/or no enhancement on CT examinations. The areas of delayed contrast enhancement corresponded to areas of extensive ...
The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to globla chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower tha 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively homogeneous areas with ...
Hyaluronic acid (HA) is a significant component of the extracellular matrix (ECM), particular interest being shown herein in synovial fluid. The present study aims to investigate the degrading effects of X-ray radiation on HA at radiotherapy doses. Measurements of viscosity and shear stresses on HA solutions have been made at different shear rates using various types of viscometer for different concentrations in the range 0.01-1% w/v of HA. The HA has been subjected to doses of 6 MV photon radiation ranging from 0 to 20 Gy, the major emphasis being on doses below 5 Gy. It is found that there is a dose-dependent relationship between viscosity and shear rate, viscosity reducing with radiation dose, this being related to polymer scissions via the action of radiation-induced free radicals. The dependency appears to become weaker at higher concentrations, possibly due to the contribution to viscosity from polymer entanglement becoming dominant over that from mean ...
Austenitic 316LN alloy was ion-irradiated using the unique Triple Ion Beam Facility (TIF) at ORNL to investigate radiation damage effects relevant to spallation neutron sources. The TIF was used to simulate significant features of GeV proton irradiation effects in spallation neutron source target materials by producing displacement damage while simultaneously injecting helium and hydrogen at appropriately high gas/dpa ratios. Irradiations were carried out at 80, 200, and 350 C using 3.5 MeV Fe{sup ++}, 360 keV He{sup +}, and 180 keV H{sup +} to accumulate 50 dpa by Fe, 10,000 appm of He, and 50,000 appm of H. Irradiations were also carried out at 200 C in single and dual ion beam modes. The specific ion energies were chosen to maximize the damage and the gas accumulation at a depth of {approximately} 1 {micro}m. Variations in microstructure and hardness of irradiated specimens were studied using transmission electron microscopy (TEM) and a nanoindentation technique, respectively. TEM ...
In this paper we discuss the results of thermoluminescence (TL) studies carried out on freshly quenched crystals of KBr doped with {approx} 50 ppm of Eu{sup 2+} ions which were X-irradiated at room temperature. The TL glow curve of this phosphor material consists of three glow peaks at 355, 376 and 398 K whose intensities increased as a function of X-irradiation time. The TL glow peaks were analyzed by the total curve-fitting method in order to obtain the characteristic parameters; activation energy, pre-exponential factor and kinetic order. The spectral character of the emission recorded during thermoluminescence was found to be the same for all glow peaks and consists of a broad band centered at {approx} 420 nm. It is proposed that the model of the TL process most consistent with our experimental results is one in which the Eu{sup 2+} impurity acts as an electron trap during the irradiation process and that the radiationinduced center ...
In this paper we discuss the results of thermoluminescence (TL) studies carried out on freshly quenched crystals of KBr doped with #approx# 50 ppm of Eu"2"+ ions which were X-irradiated at room temperature. The TL glow curve of this phosphor material consists of three glow peaks at 355, 376 and 398 K whose intensities increased as a function of X-irradiation time. The TL glow peaks were analyzed by the total curve-fitting method in order to obtain the characteristic parameters; activation energy, pre-exponential factor and kinetic order. The spectral character of the emission recorded during thermoluminescence was found to be the same for all glow peaks and consists of a broad band centered at #approx# 420 nm. It is proposed that the model of the TL process most consistent with our experimental results is one in which the Eu"2"+ impurity acts as an electron trap during the irradiation process and that the radiationinduced center (partner of an ...
Beagle dogs were given single, whole-body "6"0Co gamma-radiation exposures at one of three prenatal (8, 28, or 55 days postcoitus) or three postnatal (2, 70, or 365 days postpartum) ages to evaluate the relative radiosensitivity of various stages of brain development. A total of 387 dogs received mean doses ranging from 0.16 to 3.83 Gy, and 120 dogs were sham-irradiated. Groups of dogs were sacrificed at preselected times from 70 days to 11 years of age. Brain weight decreased significantly with increasing dose in dogs irradiated at 28 or 55 days postcoitus or at 2 days postpartum. Irradiations at 28 days postcoitus were dramatically more effective in causing a reduction in brain weight than those at 55 days postcoitus or 2 days postpartum. Among dogs given 1.0 Gy or more and followed for up to 4 years, there was a radiation effect evident at all three sensitive exposure ages. Among dogs given lower doses and followed for up to 11 years, there was a significant decrease in brain weight ...
Nitroaromatic radiosensitizers become metabolically bound preferentially to hypoxic cells and at least 10/sup 9/ adducts/cell can be tolerated as non-toxic. EMT-6 tumor cells have been incubated in hypoxia in the presence of /sup 3/H-Misonidazole and /sup 125/I-Azomycin Riboside for various times and the amount of /sup 3/H or /sup 125/I bound/cell was determined. Cells were stored as monolayers at 25"0C for up to 96 hr to accumulate radioactive decays and transferred at various times to 37"0C for colony-forming assays. No radiation inactivation was measured in cells which had incorporated at least 10/sup 6/ /sup 3/H or 10/sup 5/ /sup 125/I atoms. Previous studies had shown that -- 1% of MISO adducts to EMT-6 cells was associated with cellular DNA. These data indicate that the radiation-induced damage produced by these quantities of bound /sup 3/H or /sup 125/I causes little or not cell inactivation. The results of current studies to measure the colony-forming ...
The radiation decimal reduction dose (D_1_0) of toxigenic Vibrio cholerae O1 El Tor, Inaba was determined in vitro (0.13 kGy) and in inoculated fresh fillets of saurel (Trachurus picturatus murphyi) (0.12 kGy) and another Pacific fish species known in Peru as ''lisa'', Mugil cephalus (0.13 kGy), both of which are frequently consumed raw in ''ceviche''. The D_1_0 value was similarly determined in tails of the shrimp species Penaeus vannamei (0.13 kGy). In a second phase of the study, radiation doses in the range 1.0-4.0 kGy were evaluated for use in microbiological shelf-life extension of the selected seafood, and for adverse effects on various sensory attributes (appearance, odor, flavor, and texture). A dose of 1.0 kGy doubled the microbiological shelf-life of fish fillets during post-irradiation storage at 0-1 deg. C to approximately 30 days. This dose was deemed optimal also for preserving all sensory characteristics evaluated except appearance, due to a darkening of fillets. Best ...
In the use of doxorubicin and radiation for treatment of human malignant tumors in vivo, the relationship between treatment-induced apoptosis and Ki-67 labeling index was investigated. Four human tumor xenografts (ependymoblastoma, NNE; primitive neuroectodermal tumor, YKP; small cell lung carcinoma, GLS; glioblastoma, KYG) were transplanted under the skin of thigh of the nude mice (BALB/cA JcL-nu). The mice were given a single radiation dose of 1 Gy, or doxorubicin alone intraperitoneally at a dose of 8 mg/kg. After treatment, sections of tumor specimens were prepared from paraffin-embedded tissues. Hematoxylin and eosin staining, TUNEL staining, and immunohistochemical analysis of Ki-67 were performed. In NNE, apoptotic cells appeared most frequently after treatment compared with all other tumors, and the incidence of apoptosis in the radiation-treated group was much higher than in the doxorubicintreated group. As the incidence of apoptosis in NNE increased, the Ki-67 labeling index ...
Poly(methyl methacrylate), PMMA, Acrigel, a Brazilian polymer, is used in the manufacture of medical supplies sterilisable by ionizing radiation. However, when PMMA is gamma-irradiated it undergoes main chain scissions, which promote molecular degradation causing reduction in its physical properties. Therefore, radiolytic stabilization of PMMA is important for to become it commercially radio sterilisable. In this work we investigated the radiolytic stabilization of PMMA by using HALS (Hindered Amine Light Stabilizer) additive, commercially used for photo and thermo oxidative stabilization of polymers. The investigation of the radiation-induced main chain scissions was carried out by viscometric method. The additive added to the polymer system at 0.3 % w/w promotes a molecular radioprotection of 61%. That means a reduction of G value (scissions/100 eV) from 2.6 to 1.0. In addition, the glassy transition temperature (Tg) of PMMA (no additive), significantly changed ...
Radiation hardening in austenitic stainless steels is shown to modify deformation characteristics and correlate well with an increased susceptibility to intergranular stress corrosion cracking (IGSCC). Available data on neutron-irradiated materials have been analyzed and correlations developed between fluence, yield strength and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in the critical fluence (0.2 to 2.5 x10"2"1 n/cm"2) for IGSCC are documented. In many cases, this variability is consistent with yield strength differences among irradiated materials. IGSCC correlates better to yield strength than to fluence for most heats suggesting a possible role of radiation-induced hardening and microstructure on cracking. Microstructural evolution during proton and heavy-ion irradiation has been characterized in low-carbon 304SSs. Hardening results from a dispersion of dislocation loops in the matrix which increase in ...
Microcapsules consisting of alginate and hyaluronic acid that can be decomposed by radiation are currently under development. In this study, the composition of the microcapsule material was optimized by changing the amounts of alginate and hyaluronic acid. Solutions of 0.025%, 0.05%, 0.1%, 0.2%, or 0.4% (wt./vol.) hyaluronic acid were mixed into a 0.2% alginate solution. To these mixtures, carboplatin (0.2 mmol) was added and the resulting material was used for the capsule preparation. The capsules were prepared by spraying the material into a CaCl{sub 2} solution (0.34 mol/l) using a microatomizer. These capsules were irradiated by a single dose of 2, 5, or 10 Gy {sup 60}Co {gamma}-ray radiation. Immediately after irradiation, the releasing of core content of microcapsule was determined, using a micro particle induced X-ray emission (PIXE) camera. The average diameter of the microcapsules was 22.3 {+-} 3.3 {mu}m, and that of the liquid core was 10.2 {+-} 4.3 {mu}m. The maximum ...
Ramsar, a city in the northern Iran, has the highest level of natural background radiation in the world. It has been clearly shown that low doses of ionising radiation can induce resistance to subsequent higher exposures. This phenomenon is termed radioadaptive response. We have compared induction of cytogenetic radioadaptive response by High Natural Background Radiation (HNBR) in Ramsar and X-ray occupational exposure as conditioning doses in human peripheral blood lymphocytes. 30 healthy control individuals, living in Ramsar but in normal background radiation areas, 15 healthy individuals from Talesh Mahalleh, a region with extraordinary high level of background radiation, and 7 X-ray radiographers working in Ramsar hospital located in normal natural background ionising radiation area were evaluated. Peripheral blood samples were prepared and exposed to challenge dose of 0 and 2 Gy. Lymphocytes were scored using analysis of metaphase, for the presence of chromosomal aberrations. An ...
Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic complete remission have ...
The radiation-induced microstructural changes have been studied by cross-sectional transmission electron microscopy for single-crystal {alpha}-Al{sub 2}O{sub 3} samples irradiated with triple ion beams (0.25 MeV H{sup +}, 0.6 MeV He{sup +} and 2.4 MeV O{sup 2+}; `Triple (A)`), (0.33 MeV H{sup +}, 0.45 MeV He{sup +} and 1.3 MeV O{sup +}; `Triple (B)`) and three consecutive single ion beams (0.3 MeV H{sup +} ion followed by 0.6 MeV He{sup +} and then 0.8 MeV O{sup +} ions) at 650 C to doses in the range 0.1-8.4 dpa at the damage peak. In the specimen irradiated with Triple (A), having the same average projected range to a total peak dose of 3.7 dpa, cavities with an average diameter of 13 nm were formed between 1.2 and 1.75 {mu}m in depth causing a swelling of 0.1% at the peak, which is larger than those of the specimens irradiated with other conditions. The extent of the cavity-introduced region is some 40% smaller than observed in the damage region due to the ...
The radiation-induced microstructural changes have been studied by cross-sectional transmission electron microscopy for single-crystal #alpha#-Al_2O_3 samples irradiated with triple ion beams (0.25 MeV H"+, 0.6 MeV He"+ and 2.4 MeV O"2"+; 'Triple (A)'), (0.33 MeV H"+, 0.45 MeV He"+ and 1.3 MeV O"+; 'Triple (B)') and three consecutive single ion beams (0.3 MeV H"+ ion followed by 0.6 MeV He"+ and then 0.8 MeV O"+ ions) at 650 C to doses in the range 0.1-8.4 dpa at the damage peak. In the specimen irradiated with Triple (A), having the same average projected range to a total peak dose of 3.7 dpa, cavities with an average diameter of 13 nm were formed between 1.2 and 1.75 #mu#m in depth causing a swelling of 0.1% at the peak, which is larger than those of the specimens irradiated with other conditions. The extent of the cavity-introduced region is some 40% smaller than observed in the damage region due to the He"+ and the O"+ ions and due to the H"+ ions in the sample ...
We have observed significant differences in the response to ionizing radiation of two closely related human cell lines, and now compare the effects on these lines of both low and intermediate LET radiation. Compared to TK6, WTK1 has an enhanced X-ray survival, and is also more resistant to cell killing by {alpha}-particles. The hprt locus is more mutable in WTK1 than in TK6 by both X-rays and {alpha}-particles. WTK1 is also more mutable by {alpha}-particles than by X-rays at the hprt locus. X-ray-induced mutation at the heterozygous tk locus in WTK1 is about 25 fold higher than in TK6, while {alpha}-particle-induced mutation is nearly 50 fold higher at this locus. Also, the slowly growing tk- mutants, which comprise the majority of spontaneous and X-ray-induced tk- mutants of TK6, were not induced significantly by {alpha}-particles. Previously, we showed that TK6 has a reduced capacity for recombination compared with WTK1, and therefore, these results indicate that recombinational ...
The purified integral membrane protein, band 3, from human erythrocytes was inserted into egg lecithin liposomes. The insertion of band 3 was determined from thermal transition data from the analysis of the C-H stretching region bands recorded at temperatures from 25 to -22[sup o]C. Raman spectra show that band 3 considerably broadens and lowers the thermal transition of egg lecithin liposomes, suggesting the insertion of band 3. The band 3-inserted liposomes were irradiated with gamma-rays (40 Gy) and the radiation target groups were determined by the analysis of the structural sensitive Raman bands in the 1600-1700 cm[sup -1] (amide I), 1200-1300 cm[sup -1] (amide III) and 550-1030 cm[sup -1] (side chain amino groups) regions. The radiation-sensitive groups as identified from Raman spectra in the region 550-1030 cm[sup -1] are tyrosines and cysteines. The radiation-induced changes in the secondary structure were determined from amide I and III bands. Quantitative ...
The purified integral membrane protein, band 3, from human erythrocytes was inserted into egg lecithin liposomes. The insertion of band 3 was determined from thermal transition data from the analysis of the C-H stretching region bands recorded at temperatures from 25 to -22"oC. Raman spectra show that band 3 considerably broadens and lowers the thermal transition of egg lecithin liposomes, suggesting the insertion of band 3. The band 3-inserted liposomes were irradiated with gamma-rays (40 Gy) and the radiation target groups were determined by the analysis of the structural sensitive Raman bands in the 1600-1700 cm"-"1 (amide I), 1200-1300 cm"-"1 (amide III) and 550-1030 cm"-"1 (side chain amino groups) regions. The radiation-sensitive groups as identified from Raman spectra in the region 550-1030 cm"-"1 are tyrosines and cysteines. The radiation-induced changes in the secondary structure were determined from amide I and III bands. Quantitative estimation using the ...
Borosilicate based glass formulations have been found suitable for fixing the HLW (high level radioactive liquid waste) generated after reprocessing of the spent nuclear fuel. As the glass experiences continuous irradiation by #alpha#, #beta#a, and #gamma# radiations from the radioactive components of HLW, alteration in the glass structure may occur. Understanding of these structural evolutions of the nuclear waste glasses under irradiation is crucial to secure long term disposal and predict their behavior. In the present work, alkali based barium borosilicate glasses, having composition similar to that of Trombay Research Reactor waste glass were irradiated with high energy "1"2C beam and the radiationinduced changes were monitored by micro Raman experiment. Since a "1"2C atom can be considered as a cluster of alphas, this beam was chosen to yield linear energy losses (LET) comparable to that in case of a particles. The irradiations were ...
The development of leukemia and thyroid cancer is characterized by activation of the abl oncogene and ret oncogene, respectively. In order to clarify the relationship between these gene aberrations and radiation, the pro-myelogenous leukemia-derived cell line HL60 and the thyroid cancer-derived cell line 8505C, were irradiated in vitro with 100Gy of X-rays. RNA was then extracted from 10"8 cells of the respective cell lines and examined by the reverse transcription PCR method for rearrangements of abl and ret genes. Five kinds of positive bands were observed in the HL-60 cells irradiated with 100Gy of X-ray. Similarly, six positive bands were also observed in the 8505C cells irradiated with 100Gy. In vitro X-irradiation activation of oncogenes found in radiationinduced cancers imply that gene rearrangement by X-rays is involved in the development of malignant tumors. Furthermore, in an experiment to detect radiation effects in A-bomb ...
This report summarizes work performed by Argonne National Laboratory (ANL) on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) during the six months from October 1993 to March 1994. EAC and fatigue of piping, pressure vessels, and core components in LWRs are important concerns in operating plants and as extended reactor lifetimes are envisaged. Topics that have been investigated include (a) fatigue of low-alloy steel used in piping, steam generators, and reactor pressure vessels, (b) EAC of wrought and cast austenitic stainless steels (SSs), and (c) radiation-induced segregation and irradiation-assisted stress corrosion cracking (IASCC) of Type 304 SS after accumulation of relatively high fluence. Fatigue tests have been conducted on A302-Gr B low-alloy steel to verify whether the current predictions of modest decreases of fatigue life in simulated pressurized water reactor water are valid for high-sulfur heats that show ...
The effects of the antioxidants, vitamin E, propyl gallate, 2-t-butyl-4-methoxy phenol (BHA), 2,6-di-t-butyl-4-methoxy phenol (BHT), nor-dihydroguaiaretic acid (NDGA) and diphenyl-p-phenylene diamine (DPPD) in concentrations ranging between 0.001 per cent and 0.1 per cent have been tested on lipid peroxide formation in synthetic diet mixtures containing herring oil (10 per cent) mixed with starch (90 per cent) irradiated with #gamma#-ray doses of 100 to 2000 krad. On a weight basis NDGA, DPPD, BHA and BHT were most effective and vitamin E and propyl gallate were least effective. An antioxidant concentration of 0.01 per cent normally protected against peroxide formation after a dose of 500 krad but if the dose was increased to 1000 or 2000 krad, much higher doses of antioxidant, up to 0.1 per cent, were required to give protection. Antioxidants prevented peroxide developing during post-irradiation storage even when added after irradiation. Antioxidants were partially or completely ...
We have studied in detail the gamma radiationinduced changes in the electrical properties of the (TeO_2)_0_._9 (In_2O_3)_0 _._1 thin films of different thicknesses, prepared by thermal evaporation in vacuum. The current-voltage characteristics for the as-deposited and exposed thin films were analysed to obtain current versus dose plots at different applied voltages. These plots clearly show that the current increases quite linearly with the radiation dose over a wide range and that the range of doses is higher for the thicker films. Beyond certain dose (a quantity dependent on the film thickness), however, the current has been observed to decrease. In order to understand the dose dependence of the current, we analysed the optical absorption spectra for the as-deposited and exposed thin films to obtain the dose dependences of the optical bandgap and energy width of band tails of the localized states. The increase of the current with the gamma ...
The DNA double-strand break (DSB) damage response induced by high energy charged particles on lung fibroblast cells embedded in a 3-dimensional (3-D) collagen tissue equivalents was investigated using antibodies to the DNA damage response proteins gamma-histone 2AX (#gamma#-H2AX) and phosphorylated DNA-PKcs (p-DNA-PKcs). 3-D tissue equivalents were irradiated in positions across the linear distribution of the Bragg curve profiles of 307.7 MeV/nucleon, 556.9 MeV/nucleon, or 967.0 MeV/nucleon "5"6Fe ions at a dose of 0.30 Gy. Patterns of discrete DNA damage streaks across nuclei or saturated nuclear damage were observed, with saturated nuclear damage being more predominant as samples were positioned closer to the physical Bragg peak. Quantification of the DNA damage signal intensities at each distance for each of the examined energies revealed a biological Bragg curve profile with a pattern of DNA damage intensity similar to the physical Bragg curve for the particular energy. ...
In light water reactors, austenitic stainless steels (SSs) are used extensively as structural alloys in reactor core internal components because of their high strength, ductility, and fracture toughness. However, exposure to high levels of neutron irradiation for extended periods degrades the fracture properties of these steels by changing the material microstructure (e.g., radiation hardening) and microchemistry (e.g., radiation-induced segregation). Experimental data are presented on the fracture toughness and crack growth rates (CGRs) of wrought and cast austenitic SSs, including weld heat-affected-zone materials, that were irradiated to fluence levels as high as {approx} 2x 10{sup 21} n/cm{sup 2} (E > 1 MeV) ({approx} 3 dpa) in a light water reactor at 288-300 C. The results are compared with the data available in the literature. The effects of material composition, irradiation dose, and water chemistry on CGRs under cyclic and stress corrosion cracking ...
The most important factor in assessing radiologic risk is ensuring scientific means for evaluation of the radioactive release impact upon humans and organisms. To evaluate quantitatively this impact not only knowledge of radioactivity distribution in these dynamical systems is necessary but also understanding the transfer mechanisms between ecosystem components is needed. Thus a complete radioecologic study appear to be very complex and needs defining the source term, dynamic description of radionuclides behavior in the ecosystem, estimation of radiation doses in the major components of the ecosystem and finally the effects of radiation doses upon different parts of the systems. A diagram of the steps implied in evaluation of the effects due to radioactive effluent release in the environment is presented and discussed. The following steps are described: - identification of radioactive sources, as well as their input rate. Presence of noxious materials such as heavy metals or some ...
Simulation irradiation experiments were carried out to investigate the formation processes and contribution to hardening of radiation-induced features in low alloy steels. Medium Cu (0.12 and 0.16%) and low Cu (0.03%) A533B steels were irradiated with 3 MeV Ni ions and 5 MeV electrons, and in KUR at 290degC. Irradiated steels were examined by three-dimensional atom probe, positron annihilation, high-resolution transmission electron microscopy and hardness measurements. Electron irradiation caused almost the same hardening as KUR irradiation in medium Cu steels under almost the same dose rate and dose conditions, whereas the formation of larger, denser and more Cu enriched clusters and smaller accumulation of single vacancies were confirmed for KUR irradiation. This indicated that cascade damage provides additional cluster nucleation sites to compensate for lower free point defect production. High dose rate Ni ion irradiation produced Mn-Ni-Si clusters and ...
In this paper, we propose and implement a website of post-processing system for finite element analysis (WebDFEA). Finite element analysis is a computer-aided engineering tool and is popular for static/dynamic structure analysis. It includes three processing systems where post-processing system is to graphically demonstrate the analysis result of a structure model analyzed by finite element method. WebDFEA performs as a website. It is cross-platform because it can auto-detect a client computer platform and auto-download proper OpenGL API for drawing computer graphics. It can draw precise graphics on webpage which can be free controlled by the mouse as a manner in professional software. A database server is involved to store finite element model data and its analysis result. The graphic use...
Short synthetic single-stranded oligodeoxyribonucleotides (ssODNs) can be used to introduce subtle modifications into the genome of mouse embryonic stem cells (ESCs). We have previously shown that effective application of ssODN-mediated gene targeting in ESC requires (transient) suppression of DNA mismatch repair (MMR). However, whereas transient down-regulation of the mismatch recognition protein MSH2 allowed substitution of 3 or 4 nucleotides, 1 or 2 nucleotide substitutions were still suppressed. We now demonstrate that single- or dinucleotide substitution can effectively be achieved by transient down-regulation of the downstream MMR protein MLH1. By exploiting highly specific real-time PCR, we demonstrate the feasibility of substituting a single basepair in a non-selectable gene. Howev...
Bisphenol-A (BPA) is one of the most common environmental endocrine disrupters and has a wide range of effects on central nervous system. Adolescence is another important developmental period besides the early critical prenatal and neonatal periods. In the present study, we exposed mice to BPA (40, 400 mg/kg/d) between adolescence and young adulthood for 8 weeks and investigated its effects on the non-reproductive behaviors. In open field tests, rearing and grooming sex differences were abolished by BPA exposure. In the elevated plus maze test, the number of open arm entries, the time spent in open arms, and the number of unprotected head dips in the center area were reduced in males but increased in females by BPA at 40 or 400 mg/kg/d, thus eliminating or reversing sex differences in thes...
Fgf receptor 2c (Fgfr2c) was expressed in mature adipocytes of mouse white adipose tissue (WAT). To examine the role of Fgfr2c in mature adipocytes, we generated adipocyte-specific Fgfr2 knockout (Fgfr2 CKO) mice. The hypertrophy impairment of adipocytes in the mesenteric WAT but not in the subcutaneous WAT and decreased plasma free fatty acid (FFA) levels were observed in Fgfr2 CKO mice. Although the expression of genes involved in adipocyte differentiation and lipid metabolism in the mesenteric WAT was essentially unchanged, the expression of uncoupling protein 2 potentially involved in energy dissipation was significantly increased. Among potential Fgf ligands for Fgfr2c, Fgf9 was preferentially expressed in the mesenteric WAT. The present findings indicate that Fgfr2c potentially activ...
The laboratory environment existing outside the test situation itself can have a substantial influence on results of some behavioral tests with mice, and the extent of these influences sometimes depends on genotype. For alcohol research, the principal issue is whether genotype-related ethanol effects will themselves be altered by common variations in the lab environment or instead will be essentially the same across a wide range of lab environments. Data from 20 inbred strains were used to reduce an original battery of seven tests of alcohol intoxication to a compact battery of four tests: the balance beam and grip strength with a 1.25g/kg ethanol dose and the accelerating rotarod and open-field activation tests with 1.75g/kg. The abbreviated battery was then used to study eight inbred str...
Aims: Rapamycin (sirolimus) is an antibiotic that inhibits protein synthesis through mammalian targeting of rapamycin (mTOR) signaling, and is used as an immunosuppressant in the treatment of organ rejection in transplant recipients. Rapamycin confers preconditioning-like protection against ischemic-reperfusion injury in isolated mouse heart cultures. Our aim was to further define the role of rapamycin in intracellular Ca^2^+ homeostasis and to investigate the mechanism by which rapamycin protects cardiomyocytes from hypoxic damage. Main methods: We demonstrate here that rapamycin protects rat heart cultures from hypoxic-reoxygenation (H/R) damage, as revealed by assays of lactate dehydrogenase (LDH) and creatine kinase (CK) leakage to the medium, by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-d...
Our understanding of prenatal behavior has been significantly advanced by techniques for direct observation and manipulation of unanesthetized, behaving rodent fetuses with intact umbilical connections to the mother. These techniques involve brief administration of an inhalant anesthesic, enabling spinal transection of the rat or mouse dam, after which procedures can continue with unanesthetized dams and fetuses. Because anesthetics administered to the mother can cross the placental barrier, it is possible that fetuses are anesthetized to varying degrees. We compared in perinatal rats the effects of prenatal maternal exposure to two inhalant anesthetics: ether and isoflurane. Fewer spontaneous fetal movements and first postpartum nipple attachments were observed following maternal exposure...
The findings reported in this study highlight several important features of the development of hematopoietic stem cells after transplantation into irradiated recipients. First, they demonstrate the existence of a class of primitive multipotential stem cells that can function for a significant portion of the lifetime of a mouse (15 mo). In addition, they clearly show that these primitive stem cells can be infected with recombinant retroviruses and thus would be appropriate targets for gene therapy in somatic tissues. Second, our data indicate that the progeny of some, but not all, of the primitive stem cells have fully expanded into the various hematopoietic lineages by 2 mo after reconstitution. Finally, our analysis of the secondary recipients provides strong evidence suggesting that the primitive stem cell population can actually clonally expand. Our current experiments are aimed at determining the extent to which this expansion can occur and whether or not this ...
Many organizations are challenged with the tasks of identifying customer needs and expectations for their products, anticipating future product needs, communicating a future product vision to clients, and designing with today's technology to bring a future vision to successful realization. The design evolution of plant control centres is one aspect of CANDU development that faces such challenges. The Disney Corporation is an example of an organization that has been successful in consistently meeting these challenges for over fifty years; and some of the design practices proven in moviemaking, theme park and resort layout, and vacation experience organization may be helpful and effective when applied in other domains. This paper summarizes the findings from an examination of Disney Corporation design practices, and suggests how some practices could be used to simplify and enhance the design of future CANDU control centres. (author)
Abstract Objectives: This investigation reviewed experimental studies of laser irradiation of wound healing in mice and rats published from 2003 to August 2008, respectively, to assess putative stimulatory effects of this treatment. Background: Animal models, including rodents, attempt to reflect human wound healing and associated problems such as dehiscence, ischemia, ulceration, infection, and scarring. They have played a key role in furthering understanding of underlying mechanisms involved in impaired wound healing, and in testing new therapeutic strategies including laser irradiation. Method: Original research papers investigating effects of laser or monochromatic light therapy on wound healing in mice and rats and published from January 2003 to August 2008 were retrieved from library...
Laboratory studies have been carried out to determine the toxicity of methiocarb pellets to wild trapped wood mice in order to provide some background data prior to any further evaluation of hazard in the field. In this study, wood mice were exposed to dry and to dampened methiocarb pellets in order to reproduce field trial application conditions. Field observations of methiocarb pellets indicate that the physical character changes under dry and wet weather conditions. This may affect their relative attractiveness and potential toxicity to wood mice. The laboratory assessment of exposed wood mice included measurement of brain esterase activities, methiocarb residues in selected mouse tissue, carcasses, and histological evaluation of kidney, liver and lungs.
We report for the first time a relationship between the Tpl-2/cot oncogene and Mouse Mammary Tumor Virus (MMTV) associated transformation of mammary gland cells. A sub-genomic library generated from a primary mammary gland tumor yielded a novel MMTV integration site which disrupted the Tpl-2/cot proto-oncogene between exons 7 and 8. Comparison of a cell line derived from normal mammary gland (comma-D) and a cell line established from an MMTV induced mammary tumor (GR) demonstrated similar rearrangements within Tpl-2/cot for the GR cells but not in the comma-D cells. These rearrangements in the cell line were accompanied by an increase in the level of Tpl-2/cot specific mRNA. This data suggests that Tpl-2/cot expression may be important in epithelial cell transformation or tumor progression. PMID:8934549
Sulfur mustard (HD) is an alkylating and cytotoxic chemical warfare agent, which inflicts severe skin toxicity and an inflammatory response. Effective medical countermeasures against HD-caused skin toxicity are lacking due to limited knowledge of related mechanisms, which is mainly attributed to the requirement of more applicable and efficient animal skin toxicity models. Using a less toxic analog of HD, chloroethyl ethyl sulfide (CEES), we identified quantifiable inflammatory biomarkers of CEES-induced skin injury in dose- (0.05-2 mg) and time- (3-168 h) response experiments, and developed a CEES-induced skin toxicity SKH-1 hairless mouse model. Topical CEES treatment at high doses caused a significant dose-dependent increase in skin bi-fold thickness indicating edema. Histopathological e...
The recent breakthrough in the generation of rat embryonic stem cells (rESCs) opens the door to application of gene targeting to create models for the study of human diseases. In addition, the in vitro differentiation system from rESCs into derivatives of three germ layers will serve as a powerful tool and resource for the investigation of mammalian development, cell function, tissue repair, and drug discovery. However, these uses have been limited by the difficulty of in vitro differentiation. The aims of this study were to establish an in vitro differentiation system from rESCs and to investigate whether rESCs are capable of forming terminal-differentiated cardiomyocytes. Using newly established rESCs, we found that embryoid body (EB)-based method used in mouse ESC (mESC) differentiation...
The ultimate goal of this research is to generate and apply novel technologies to speed completion and integration of the human genome map and sequence with biomedical problems. To do this, techniques were developed and genome-wide resources generated. This includes a genome-wide Mapped and Integrated BAC/PAC Resource that has been used for gene finding, map completion and anchoring, breakpoint definition and sequencing. In the last period of the grant, the Human Mapped BAC/PAC Resource was also applied to determine regions of human variation and to develop a novel paradigm of primate evolution through to humans. Further, in order to more rapidly evaluate animal models of human disease, a BAC Map of the mouse was generated in collaboration with the MTI Genome Center, Dr. Bruce Birren.
Photoacoustic microscopy (PAM) offers label-free, optical absorption contrast. A high-speed, high-resolution PAM system in an inverted microscope configuration with a laser pulse repetition rate of 100,000 Hz and a stationary ultrasonic transducer was built. Four-dimensional in vivo imaging of microcirculation in mouse skin was achieved at 18 three-dimensional volumes per second with repeated two-dimensional raster scans of 100 by 50 points. The corresponding twodimensional B-scan (50 A-lines) frame rate was 1800 Hz, and the one-dimensional A-scan rate was 90,000 Hz. The lateral resolution is 0.23+/-0.03 ?m for Au nano-wire imaging, which is 2.0 times below the diffraction limit.
Glucagon plays critical roles in regulating glucose homeostasis, mainly by counteracting the effects of insulin. Consequently, the dysregulated glucagon secretion that is evident in type 2 diabetes has significant implications in the pathophysiology of the disease. Glucagon secretion from pancreatic -cells has been suggested to be modulated by blood glucose, signals from the nervous system and endocrine components. In addition to these regulators, intraislet factors acting in a paracrine manner from neighbouring -cells are emerging as central modulator(s) of -cell biology. One of the most important of these paracrine factors, insulin, modulates glucagon secretion. Indeed, the -cell-specific insulin receptor knockout (IRKO) mouse manifests hypersecretion of glucagon in the postprandial stag...
Obesity is associated with increased susceptibility to dyslipidemia, insulin resistance, and hypertension, a combination of traits that comprise the traditional definition of the metabolic syndrome. Recent evidence suggests that obesity is also associated with the development of nonalcoholic fatty liver disease (NAFLD). Despite the high prevalence of obesity and its related conditions, their etiologies and pathophysiology remains unknown. Both genetic and environmental factors contribute to the development of obesity and NAFLD. Previous genetic analysis of high-fat, diet-induced obesity in C57BL/6J (B6) and A/J male mice using a panel of B6-ChrA/J/NaJ chromosome substitution strains (CSSs) demonstrated that 17 CSSs conferred resistance to high-fat, diet-induced obesity. One of these CSS st...
Summary Metabotropic GABAB receptors play a fundamental role in modulating the excitability of neurons and circuits throughout the brain. These receptors influence synaptic transmission by inhibiting presynaptic release or activating postsynaptic potassium channels. However, their ability to directly influence different types of postsynaptic glutamate receptors remains unresolved. Here we examine GABAB receptor modulation in layer 2/3 pyramidal neurons from the mouse prefrontal cortex. We use two-photon laser-scanning microscopy to study synaptic modulation at individual dendritic spines. Using two-photon optical quantal analysis, we first demonstrate robust presynaptic modulation of multivesicular release at single synapses. Using two-photon glutamate uncaging, we then reveal that GABAB r...
Erythroid differentiation regulator (Erdr1) was first discovered in mouse leukemia cell lines and functions as a stress-related survival factor. This study investigated whether Erdr1 regulates murine melanoma progression, as well as the mechanism involved in Erdr1-regulated metastasis. The expression of Erdr1 is negatively correlated with IL-18 expression, which has a pro-cancer effect in melanoma. To study the role of Erdr1 as an anti-cancer factor, cell migration, invasion, and proliferation were measured. Erdr1 overexpression markedly inhibited the level of cell migration, invasion, and proliferation in B16F10 cells in vitro. In addition, Erdr1 overexpression significantly suppressed melanoma lung colonization, metastasis, and tumor growth in vivo. To identify the factors involved in Er...
The effects of dietary plant and yeast cerebroside (glucosylceramide), a major sphingolipid in plants and yeast, on atopic dermatitis (AD) like symptoms were investigated in a mouse model. After 7 wk of feeding with a diet containing maize glucosylceramide, plasma IgE levels became significantly lower and in contrast, the levels of interleukin (IL)-12, which induces cellular immunity, became significantly higher in the AD mice than in the controls. However, the sphingolipid constituents of the skin fraction in the maize glucosylceramide fed group did not contain sphingoid bases of plant origin, such as 8-unsaturated sphingoid bases. The results of the present study indicated that dietary plant glucosylceramide prevented AD-like symptoms in AD model mice via regulation of Th1/Th2 balance. P...
Evolutionary conservation of DNA sequences provides a tool for the identification of functional elements in genomes. We have created a database of evolutionary conserved regions (ECRs) in vertebrate genomes entitled ECRbase that is constructed from a collection of pairwise vertebrate genome alignments produced by the ECR Browser database. ECRbase features a database of syntenic blocks that recapitulate the evolution of rearrangements in vertebrates and a collection of promoters in all vertebrate genomes presented in the database. The database also contains a collection of annotated transcription factor binding sites (TFBS) in all ECRs and promoter elements. ECRbase currently includes human, rhesus macaque, dog, opossum, rat, mouse, chicken, frog, zebrafish, and two pufferfish genomes. It is freely accessible at http://ECRbase.dcode.org.
XMRV or xenotropic murine leukemia virus-related retrovirus, a recently discovered retrovirus, has been linked to both prostate cancer and chronic fatigue syndrome (CFS). Recently, the teams of Drs. Shyh-Ching Lo and Harvey Alter discovered the presence of sequences closely related to XMRV in the blood of 86.5% of patients with CFS [1]. These findings are important because since the initial discovery of XMRV in CFS, several studies have failed to find XMRV in specimens collected from CFS patients. While the current study also did not find XMRV in CFS, Lo et al. did detect sequences that belong to polytropic mouse endogenous retroviruses (PMV), which share considerable similarity with XMRV. Criteria for future studies that will help bring greater clarity to the issue of retroviral sequences in CFS are proposed below. PMID:21994623
Purpose. The paper introduces a novel design of air-core inductive sensors in printed circuit board (PCB) technology for a tongue control system. The tongue control system provides a quadriplegic person with a keyboard and a joystick type of mouse for interaction with a computer or for control of an assistive device. Method. Activation of inductive sensors was performed with a cylindrical, soft ferromagnetic material (activation unit). Comparative analysis of inductive sensors in PCB technology with existing hand-made inductive sensors was performed with respect to inductance, resistance, and sensitivity to activation when the activation unit was placed in the center of the sensor. Optimisation of the activation unit was performed in a finite element model. Results. PCBs with air-core indu...
In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.
In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.
Amphiphysin is a protein concentrated in neuronal synapses and peripherally associated with neurotransmitter vesicles. It is expressed in many neurons of the central and peripheral nervous systems, in the adrenal medulla, in the anterior and posterior pituitary, in cell lines of the endocrine pancreas, and in spermatocytes. Its subcellular localization and tissue distribution indicate a potential involvement in mechanisms of regulated exocytosis. A role in the dynamic organization of the membrane-associated cytoskeleton is suggested by structural homology to the products of two yeast genes, RVS161 and RVS167, whose mutation results in an abnormal actin distribution, disturbs budding morphology, and impairs cell entry into stationary phase. Limited stretches of sequence similarity, including an SH3 domain, are also shared with other actin-binding proteins. Amphiphysin is the dominant autoantigen in paraneoplastic Stiff-Man syndrome, a neurological autoimmune disorder characterized by ...
Background: Some former retrospective studies have suggested that patients with Ewing's sarcoma might have a very high risk for developing secondary sarcomas if treated with radiotherapy. We have evaluated the risk of second malignancies (SM) in patients treated in the German Cooperative Ewing's Sarcoma Studies CESS 81 and CESS 86. Materials and methods: From January 1981 through June 1991, a total number of 674 patients was registered in the two multicentric Ewing's sarcoma trials CESS 81 (1981 through 1985) and CESS 86 (1986 through June 1991). The systemic treatment consisted in both studies of a four-drug-chemotherapy (VACA= vincristine, actinomycin D, cyclophosphamide and adriamycin; or VAIA= vincristine, actinomycin D, ifosfamide and adriamycin) and a total number of four courses, each lasting nine weeks, was recommended by the protocol. Local therapy was either complete surgery or surgery plus postoperative radiotherapy with 36-46Gy or definitive radiotherapy with 46 to 60Gy. ...
Background and purpose: The low density of lung tissue causes a reduced attenuation of photons and an increased range of secondary electrons, which is inaccurately predicted by the algorithms incorporated in some commonly available treatment planning systems (TPSs). This study evaluates the differences in dose in normal lung tissue computed using a simple and a more correct algorithm. We also studied the consequences of these differences on the dose-effect relations for radiation-induced lung injury. Materials and methods: The treatment plans of 68 lung cancer patients initially produced in a TPS using a calculation model that incorporates the equivalent-pathlength (EPL) inhomogeneity-correction algorithm, were recalculated in a TPS with the convolution-superposition (CS) algorithm. The higher accuracy of the CS algorithm is well-established. Dose distributions in lung were compared using isodoses, dose-volume histograms (DVHs), the mean lung dose (MLD) and the ...
There are very different views on the health hazards of DU munitions. Most of the concerns of veterans and their advisors focus on the radiological effects of DU and consequently these are the focus of this editorial. Effects on the kidney and environmental consequences are, however, considered in the second of the Royal Society reports and the main conclusions of both of the reports are outlined in the summary document published in this issue of the journal. The main radiological concerns focus on the irradiation of lung tissues from inhaled DU particles and irradiation resulting from the translocation of inhaled particles to the thoracic lymph nodes.The overwhelming scientific view, presented in the two Royal Society reports and in other independent reviews, is that the main risks of exposure to DU aerosols are an increase in lung cancer and (from chemical toxicity) damage to the kidney, although these are likely to be evident only following substantial intakes. The equivalent doses ...
The three mammalian transforming growth factor (TGF)-? isoforms (TGF-?1, TGF-?2, and TGF-?3) differ in their putative roles in radiation-induced fibrosis in intestine and other organs. Furthermore, tissue specificity of TGF-? action may result from temporal or spatial changes in production and/or activation. The present study examined shifts in the cell types expressing TGF-? mRNA relative to TGF-? immunoreactivity and histopathological injury during radiation enteropathy development. A 4-cm loop of rat small intestine was locally exposed to 0, 12, or 21-Gy single doses of x-irradiation. Sham-irradiated and irradiated intestine were procured 2 and 26 weeks after irradiation. Cells expressing the TGF-?1, TGF-?2, or TGF-?3 transcripts were identified by in situ hybridization with digoxigenin-labeled riboprobes. Intestinal wall TGF-? immunoreactivity was measured using computerized image analysis, and structural radiation injury was assessed by quantitative ...
PCR detection of genetic material of the parasites present in faeces may be an alternative for microscopic and serological tests routinely used for diagnosing parasitic enteral infections. However, small amount of target DNA combined with low efficiency of total DNA extraction, and presence of PCR inhibitors in the samples to be amplified, may cause false negative detection results. The aim of this work was to evaluate the impact of DNA isolation procedure used on the amplification of DNA fragments from the genomes of protozoan Cryptosporidium parvum and the nematode Trichinella spiralis. Two methods based on different principles of biological material lysis were evaluated; NucliSENS miniMAG employing simultaneously applied chemical lysis and mechanical disruption or mechanical disruption followed by enzymatic lysis in case of QIAamp DNA Stool Mini Kit. Both of the analyzed systems for nucleic acids purification allowed isolation of DNA from purified Cryptosporidium parvum oocysts and ...
Dose-response studies of the radiosensitivity of spermatogonial stem cells in various epithelial stages after irradiation with graded doses of fission neutrons of 1 MeV mean energy were carried out in the Cpb-N mouse. These studies on the stem cell population in stages IX-XI yielded simple exponential lines characterized by an average D0 value of 0.76 +/- 0.02 Gy. In the subsequent epithelial stages XII-III, a significantly lower D0 value of 0.55 +/- 0.02 Gy was found. In contrast to the curves obtained for stem cells in stages IX-III, the curves obtained in stages IV-VIII indicated the presence of a mixture of radioresistant and radiosensitive stem cells. In stage VII, almost no radioresistant stem cells appeared to be present and a D0 value for the radiosensitive stem cells of 0.22 +/- 0.01 Gy was derived. Previously, data were obtained on the size of colonies (in number of spermatogonia) derived from surviving stem cells. Combining these data with data from the ...
In the bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537, gamma irradiated hyaluronic acid (10 and 50 kGy) did not induce a significant increase in the number of revertant colonies in the presence of S9 metabolic activation system. In chromosomal aberration tests with CHO cells, gamma irradiated hyaluronic acid (10 and 50 kGy) did not result in an increase in the frequency of chromosomal aberrations. In vivo mouse micronucleus assay, gamma irradiated hyaluronic acid (10 and 50 kGy) did not show an increase in the frequency of polychromatic erythrocytes with micronuclei. These results indicate that hyaluronic acids irradiated at 10 and 50 kGy did not show any genotoxic effects under these experimental conditions. In order to evaluate their possible subacute toxicity, the male and female of ICR mouse were given to methanol extract of 50 kGy irradiated red ginseng and 20 kGy irradiated water extract of mistletoe for ...
The purpose of this study is to evaluate the therapeutic efficacy of the liposome encaged with vinorelbine (VNB) and "1"1"1In-oxine on human colorectal adenocarcinoma (HT-29) using HT-29/luc mouse xenografts. HT-29 cells stably transfected with plasmid vectors containing luciferase gene (luc) were transplanted subcutaneously into the male NOD/SCID mice. Biodistribution of the drug was performed when tumor size reached 500-600 mm"3. The uptakes of "1"1"1In-VNB-liposome in tumor and normal tissues/organs at various time points postinjection were assayed. Multimodalities, including gamma scintigraphy, bioluminescence imaging (BLI) and whole-body autoradiography (WBAR), were applied for evaluating the therapeutic efficacy when tumor size was about 100 mm"3. The tumor/blood ratios of "1"1"1In-VNB-liposome were 0.044, 0.058, 2.690, 20.628 and 24.327, respectively, at 1, 4, 24, 48 and 72 h postinjection. Gamma scinitigraphy showed that the tumor/muscle ratios were 2.04, ...
The sequence segment 181-200 of the Torpedo nicotinic acetylcholine receptor (nAChR) #alpha#subunit forms a binding site for #alpha#-bungarotoxin (#alpha#-BTX). Synthetic peptides corresponding to the homologous sequences of human, calf, mouse, chicken, frog, and cobra muscle nAChR #alpha#1 subunits were tested for their ability to bind "1"2"5I-#alpha#-BTX, and differences in #alpha#-BTX affinity were determined by using solution (IC_5_0s) and solid-phase (K_ds) assays. Panels of overlapping peptides corresponding to the complete #alpha#1 subunit of mouse and human were also tested for #alpha#-BTX binding, but other sequence segments forming the #alpha#-BTX site were not consistently detectable. The role of a putative vicinal disulfide bound between Cys-192 and -193, relative to the Torpedo sequence, was determined by modifying the peptides with sulfhydryl reagents. Reduction and alkylation of the peptides decreased #alpha#-BTX binding, whereas ...
Paraquat (1,1'-dimethyl-4,4'-bipyridinium) is a widely used herbicide known to induce skin toxicity. This is thought to be due to oxidative stress resulting from the generation of cytotoxic reactive oxygen intermediates (ROI) during paraquat redox cycling. The skin contains a diverse array of antioxidant enzymes which protect against oxidative stress including superoxide dismutase (SOD), catalase, glutathione peroxidase-1 (GPx-1), heme oxygenase-1 (HO-1), metallothionein-2 (MT-2), and glutathione-S-transferases (GST). In the present studies we compared paraquat redox cycling in primary cultures of undifferentiated and differentiated mouse keratinocytes and determined if this was associated with oxidative stress and altered expression of antioxidant enzymes. We found that paraquat readily undergoes redox cycling in both undifferentiated and differentiated keratinocytes, generating superoxide anion and hydrogen peroxide as well as increased protein oxidation which ...
A major regulatory element required for expression of the human [alpha]-globin genes is located 40 kb upstream of the embryonic [zeta]-globin gene. To understand how this and other locus control region (LCR) elements contribute to high-level expression in erythroid cells, we have performed high-resolution, in vivo dimethyl sulfate footprinting. In addition, we have modified the dimethyl sulfate-based ligation-mediated polymerase chain reaction in vivo footprinting procedure to permit the assessment of interactions at guanine and adenine residues, rather than guanines alone. In vivo footprinting of the human [alpha]-LCR element carried on chromosome 16 in a mouse erythroleukemia cell environment revealed protein occupancy at GATA-1, AP-1/NF-E2, and CACC/GGTGG motifs, specific differences compared with in vitro protein binding, and distinct changes in one region upon dimethyl sulfoxide-induced cellular maturation. No protein contacts were detected in nonexpressing ...
The detection and quantification of defined reaction products of chemical mutagens and carcinogens (and of many cancer chemotherapeutic agents) with DNA require highly sensitive analytical techniques. The exceptional capability of immunoglobulins to recognize subtle alterations of molecular structure (especially when monoclonal antibodies are used to maximize specificity), outstanding sensitivity of immunoanalysis by high-affinity antibodies, and the fact that radioactively-labelled agents are not required suggest the utility of a radioimmunoassay to recognize and quantitate alkylated DNA products. We have recently developed a set of high-affinity monoclonal antibodies (secreted by mouse x mouse as well as by rat x rat hybridomas; antibody affinity constants, 10"9 to > 10"1"0 lmol) specifically directed against several DNA alkylation products with possible relevance in relation to both mutagenesis and malignant transformation of mammalian ...
Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced /sup 86/Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. /sup 86/Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated /sup 86/Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine 5'-(beta, gamma-imido)triphosphate ...
Despite extensive clinical use of thallium-201 (/sup 201/Tl) for myocardial imaging, the effect of ischemia on myocardial accumulation and release of /sup 201/Tl independent of flow has not been fully defined. Therefore, myocardial accumulation of /sup 201/Tl in response to ischemic-like myocardial injury was assessed in vitro using the cultured fetal mouse heart preparation. Cultured fetal mouse hearts (n . 311) were subjected to injury simulating ischemia by deprivation of oxygen and oxidizable substrates for periods ranging from 15 minutes to 10 hours. The extent of irreversible injury was determined by the percentage of lactic dehydrogenase (LDH) lost from the hearts to the culture medium during recovery from injury. Injury was essentially reversible at 1 hour of insult. The fraction of /sup 201/Tl content in injured compared with control hearts was not significantly lower after 1 hour of insult. By 3 hours of insult, irreversible injury as ...
Duchenne and Becker muscular dystrophies are caused by defects of dystrophin, which forms a part of the membrane cytoskeleton of specialized cells such as muscle. It has been previously shown that the dystrophin-associated protein A1 (59-kDa DAP) is actually a heterogeneous group of phosphorylated proteins consisting of an acidic ({alpha}-A1) and a distinct basic ({beta}-A1) component. Partial peptide sequence of the A1 complex purified from rabbit muscle permitted the design of oligonucleotide probes that were used to isolate a cDNA for one human isoform of A1. This cDNA encodes a basic A1 isoform that is distinct from the recently described syntrophins in Torpedo and mouse and is expressed in many tissues with at least five distinct mRNA species of 5.9, 4.8, 4.3, 3.1, and 1.5 kb. A comparison of the human cDNA sequence with the GenBank expressed sequence tag (EST) data base has identified a relative from human skeletal muscle, EST25263, which is probably a human ...
The transcriptional silencing of some cell cycle inhibitors and tumor suppressors, such as p16 and retinoic acid receptor beta(2), by DNA hypermethylation at CpG islands is commonly found in human oral squamous carcinoma cells. We examined the effects of the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5-Aza; 0.25 mg/kg body weight), all-trans retinoic acid (RA; given at 100 microg/kg body weight and 1 mg/kg body weight), and the combination of 5-Aza and the low-dose RA on murine oral cavity carcinogenesis induced by the carcinogen 4-nitroquinoline 1-oxide (4-NQO) in a mouse model. All the drug treatments were done for 15 weeks after a 10-week 4-NQO treatment. Mice in all drug treatment groups showed decreases in the average numbers of neoplastic tongue lesions. The combination of 5-Aza and RA effectively attenuated tongue lesion severity. Although all drug treatments limited the increase in the percentage of proliferating cell nuclear antigen-positive ...
Purpose: To assess the benefit and the effect of intraarterial lipiodol application on histological analysis of patients suspected of having HCC. To determine whether lipiodol marking leads to a better biopsy result and how lipiodol or a transarterial chemoembolization influences the histological diagnosis. Materials and Methods: Two groups of patients were examined. Group A included 14 patients highly suspected of having an HCC which had previously been unsuccessfully biopsied. A transarterial embolization with lipiodol was performed in these patients to mark intrahepatic tumors which could not otherwise be defined in unenhanced CT. A biopsy was then repeated. Group B included 22 patients undergoing therapy using transarterial chemoembolization (TACE). A biopsy was performed to support the diagnosis of a multifocal HCC before changing the therapy. Results: The transversal diameters of the biopsied tumors were similar in both groups (A: 22 mm; B: 21 mm). The length of percutaneous ...
A retrospective review was made of 2,659 autopsy patients obtained during the past 31 years and a half in Hiroshima Atomic Bomb Hospital. Of the patients, 1,328 (49.9%) were A-bomb survivors. Five hundred and six A-bomb survivors (38.1%) had been exposed at up to 2,000 m from the hypocenter. There was no correlation between the incidence of malignancy and the presence of exposure to A-bombing. The incidence of multiple malignancy was slightly higher in A-bomb survivors exposed at the place nearer the hypocenter. In the group of A-bomb survivors, cancer of the lung was the most common for men; and cancer of the stomach was the most common for women. The incidence of malignancy has been high in the exposed group during the early eras of examination; however, this figure has recently become high in the non-exposed group. Regarding the kinds of malignancy, there was no significant difference between the exposed and non-exposed groups. The incidence of leukemia was high during the early ...
A significant challenge in proteomics biomarker research is to identify the changes that are of highest diagnostic interest, among the many unspecific aberrations associated with disease burden and inflammation. In the present study liver tissue specimens (n=18) from six experimental stages were collected from the resistant hepatocyte (RH) rat model of liver cancer and analyzed by 2D DIGE. The study included triplicates of regenerating liver, control "sham-operated" liver, three distinct premalignant stages and hepatomas. Out of 81 identified proteins two-thirds were differentially abundant in rat hepatomas compared to control rat liver and, secondly, the majority of proteins were also changed in precursor stages. This underscores the importance of adequate control samples in explorative cancer biomarker research. We confirm several proteomic changes previously identified in human hepatocellular carcinoma (HCC) and we identify novel candidate proteomic aberrations ...
Computed tomography would be a better method to detect and characterize a Thorotrast-induced liver tumour. The selective opacification of the RES by Thorotrast creates an intrinsic opacification of the liver similar in effect to contrast agents being evaluated for liver CT, such as ethoioidized oil emulsion. The computed tomographic appearance of Thorotrast-associated cholangiocarcinoma is usually a large, inhomogenous mass composed of disordered area of tissue of high density due to Thorotrast deposits, and of very low density. Thorotrast-induced cholangiocarcinoma originates in the peripheral biliary tree suprounding the highest mean concentration of Thorotrast deposition, so that visible soft tissue masses in the higher density spots in the liver are not produced in the early stage. The tendency for the opacity of the liver to decrease slowly with time and result in an uneven trabeculation and high density spots suggests that small tumors may be difficult to detect againist such an ...
Cholangiocarcinoma is synonymous with bile duct carcinoma, and can originate in a small intrahepatic bile duct (peripheral type), a major intrahepatic duct including the hepatic hills, an extrahepatic duct, or near the papilla of Vater (central type). In a sense bile duct carcinoma of the peripheral type is cholangiocarcinoma of the liver; it has the same gross configuration as hepatocellular carcinoma, resulting in difficulty to differentiate on the CT. The authors studied CT findings of 14 cases of pathologically proven peripheral type cholangiocarcinoma of the liver during the last 4 years. The results were as follows: 1. Of 14 cases, 8 were female and 6 were male, and the age ranged from 5th to 7th decades. 2. Preoperative clinical diagnosis were as follows: hepatoma 8 cases, abscess 5 cases and metastasis 1 case in order of frequency. 3. Diagnosis were confirmed by hepatic lobectomy in 7 cases, wedge resection in 5 cases and needle biopsy in 2 case. 4. ...
Lipiodol, lipid soluble contrast media, was applied to 59 patients, who was clinically suspected to have hepatic tumor, in the Department of Diagnostic Radiology, Seoul National University Hospital. The results of the clinical use of Lipiodol were as follows: 1. The clinical diagnosis was hepatocellular carcinoma (HCC) in 50 cases, cavernous hemangioma in 4 cases, metastasis in one case and others in 4 cases. 2. After hepatic arteriography, Lipiodol only was injected in 28 cases, mixture of Lipiodol and Mitomycin was injected in 22 cases and transcatheter arterial embolization was performed additionally after injection of Lipiodol and Mitomycin in 9 cases. 3. Among the 50 cases of HCC, Lipiodol was accumulated in the lesion in 49 cases. However, similar accumulation of Lipiodol occured in a metastatic cancer and cavernous hemangiomas. 4. Plain radiographic patterns of Lipiodol accumulation could be divided into fine granular type, nodular type and linear or ...
The hepatic artery chemoembolization with Lipiodol, doxorublicin. Gelfoam was performed in 14 mongrel dogs to evaluate embolic effect of these materials to normal liver parenchyma. Fourteen dogs were divided into four experimental groups according to the kinds of embolic materials. 3 dogs with 0.1ml/kg of Lipiodol (Group 1), 4 dogs with 0.1ml/kg of Lipiodol and 0.5mg/kg of doxorubicin (Group 2). 4 dogs with Lipiodol, doxorubicin and 150-300 pieces of 0.5 x 0.5cm sized Gelfoam (Group 3), 3 dogs with Gelfoam alone (Group 4). Follow-up liver function tests and liver CT were performed 1 day, 3 day, 1 week, 2 weeks and 3 weeks after embolization. Pathologic examination was performed 3 weeks after embolization. Lipiodol densities in group 1 were cleared 2 weeks after embolization, and in group 2, patch and nodular Lipiodol densities were changed to mottled and streaky densities 3 weeks after chemoembolization. In group 3, patch and nodular Lipiodol densities were still remained 3 weeks after ...
The presence of endothelin (ET)-like immunoreactivity and the cardiovascular effects of mammalian ET-1 in fish have been reported. To identify ET-related peptides in fish, we screened the cDNA library of the salmon (Oncorhynchus keta) stomach by means of rapid amplification of cDNA ends, and we cloned cDNAs encoding an ET-related peptide. The salmon ET-related sequence of 21 amino acids is identical to the trout ET-1 peptide recently purified from kidney specimens of Oncorhynchus mykiss. The deduced amino acid sequence of salmon pre-proET-1 (PPET-1) comprises 244 amino acids, including a putative signal sequence and mature ET-1, as well as big ET-1 and ET-1-like sequences. This precursor, the first reported PPET-1 sequence for Salmoniformes, Teleostei, has low homology with the sequences of human, mouse, frog (Xenopus laevis), and zebrafish (Danio rerio) PPET-1 (26%, 29%, 24%, and 39%, respectively). PMID:16740985
Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1), a cold-inducible coactivator of nuclear receptors, stimulates mitochondrial biogenesis and respiration in muscle cells. In the present study, we first cloned a rat PGC-1 gene from a brown adipose tissue cDNA library which encodes a predicted 796-amino-acid protein and exhibits respectively 98% and 95% identity with the mouse and human homologues. Next, we examined the effect of swimming exercise training on the level of expression of the PGC-1 gene in rat epitrochlearis (Epi) muscle. PGC-1 mRNA level in Epi muscle in rats that swam 2 h a day for 3 and 7 days increased dramatically by 154% and 163%, respectively, compared to the non-exercised control group. PGC-1 mRNA up-regulation was not observed in an immersion group treated at 35 degrees C during the training program but without swimming exercise. These results demonstrate that expression of the PGC-1 gene in Epi muscle is induced not only ...
Cytosine methylation in DNA is a major epigenetic signal, and plays a central role in propagating chromatin status during cell division. However the mechanistic links between DNA methylation and histone methylation are poorly understood. A multi-domain protein UHRF1 (ubiquitin-like, containing PHD and RING finger domains 1) is required for DNA CpG maintenance methylation at replication forks, and mouse UHRF1-null cells show enhanced susceptibility to DNA replication arrest and DNA damaging agents. Recent data demonstrated that the SET and RING associated (SRA) domain of UHRF1 binds hemimethylated CpG and flips 5-methylcytosine out of the DNA helix, whereas its tandom tudor domain and PHD domain bind the tail of histone H3 in a highly methylation sensitive manner. We hypothesize that UHRF1 brings the two components (histones and DNA) carrying appropriate markers (on the tails of H3 and hemimethylated CpG sites) ready to be assembled into a nucleosome after ...
The tissue distribution of "1"3"1I-transferrin ("1"3"1I-Tf) was studied in athymic nude mice having s.c. human colonic adenocarcinoma HT-29 xenografts. Four days after "1"3"1I-Tf injection, the "1"3"1I specific activity measured in the HT-29 tumor, i.e. amount of radioactivity per gram of fresh tissue, represented 0.31 #+-# 0.09% of the injected radioactivity and was 1.90 fold more than that measured in the murine colon (P < 0.05). After correction for intravascular "1"3"1I-Tf as estimated by mean of "9"9"mTc-Sn in vivo labeling of red blood cells, the "1"3"1I specific activity observed in the HT-29 tumor was 7.21 fold more than that observed in the murine colon. This subtracting method enabled us to localize a HT-29 tumor xenograft by #gamma# scintigraphy of the entire animal and demonstrated that "1"3"1I-Tf could be a non-specific but potent marker for human colon cancer. (author).
The elucidation on the metabolic products of the {sup 99}mTc-antibody conjugates may provide insights and approaches that would reduce the undesirable deposition of radioactive species in normal tissue. In this investigation, the radiolabeled species in blood, urine, bile and extracts of liver and kidney obtained at different times after the injection of a model antibody, {sup 99}mTc, into mice were analyzed with various chromatographic methods. Ninety-nine to 100% of the radioactivity in serum was associated with intact Mab 170. The radioactivity in liver homogenate extract was strictly protein-bound to either intact Mab or low molecular weight species (LMW). In kidney extracts, the majority of the radioactivity was protein bound {sup 99}mTc, with less than 8% of the activity being non- protein bound . Multiple {sup 99}mTc -containing protein and non-protein species were found in urine and bile. Evidence supporting the presence of {sup 99}mTc-cysteine and {sup 99}mTc-glutathione in ...
The ability of Yersinia pestis to forestall the mammalian innate immune response is a fundamental aspect of plague pathogenesis. In this study, we examined the effect of Ail, a 17-kDa outer membrane protein that protects Y. pestis against complement-mediated lysis, on bubonic plague pathogenesis in mice and rats. The Y. pestis ail mutant was attenuated for virulence in both rodent models. The attenuation was greater in rats than in mice, which correlates with the ability of normal rat serum, but not mouse serum, to kill ail-negative Y. pestis in vitro. Intradermal infection with the ail mutant resulted in an atypical, subacute form of bubonic plague associated with extensive recruitment of polymorphonuclear leukocytes (PMN or neutrophils) to the site of infection in the draining lymph node and the formation of large purulent abscesses that contained the bacteria. Systemic spread and mortality were greatly attenuated, however, and a productive adaptive immune ...
Understanding risks from exposures to carcinogens and other chemicals depends upon measurement of their dose to target tissues and their reactivity with critical macromolecules. The authors have used AMS detection of radio-isotopes to assess doses and reactivities at low, environmentally relevant doses. Several biomedical investigations show the effectiveness of quantification of biologically important events at extremely high sensitivity with AMS. Specifically, they have measured the addition of environmental carcinogens such as 2-amino-3,8-dimethylimidazo[4,5-f]-quinoaxaline (MelQx), a chemical found in cooked food, to DNA at concentrations relevant to human exposure. Other low level detection problems in biology, such as immunoassay assessment of small environmental chemicals, is being developed with attomole sensitivity. AMS also aids the assessment of genotoxic risks from chemicals by quantifying the binding of labeled chemicals to DNA. The very toxic and potent carcinogen, ...
Neuron-restrictive silencer factor (NRSF) binds its consensus element to repress the transcription of various genes. The dominant-negative form (dnNRSF) has a hypertrophic effect on cardiogenesis through an unidentified mechanism. We examined the involvement of transient receptor potential (TRP) channel proteins, using transgenic mice overexpressing dnNRSF (dnNRSF mice). Electrophoretic mobility-shift assays revealed an interaction between NRSF and a neuron-restrictive silencer element-like sequence in intron 4 of TRPC1 genomic DNA. According to RT-PCR and Western analyses, TRPC1 was up-regulated in dnNRSF mouse heart. Transient overexpression of TRPC1 in HEK 293T cells increased the activity of the nuclear factor in activated T cells (NFAT) promoter and stimulated store-operated Ca"2"+ channel (SOCC)-mediated Ca"2"+ entry. Transfection of TRPC1 into primary cardiomyocytes increased NFAT activity, indicating a major role for TRPC1 in NFAT activation. Our findings ...
The Thomsen-Friedenreich (T) antigen, #betta#-D-Gal-(1->3)-#alpha#-D-GalNAc, is exposed in reactive form on many human adenocarcinomata, but not on corresponding benign tissues. Peanut lectin (PNA) has a strong binding affinity for the T antigen and reportedly binds preferentially to certain malignant tissues. We investigated the potential of radio-labelled PNA as a tumour localising agent in an animal model system using a mouse lymphoma (RI) shown to bind fluorescein-labelled PNA in vitro. The radio-iodinated lectin showed good tumour localisation and rapid blood clearance. Clear images of tumours were obtained, in serial scintigraphic imaging, by 24 and 48 h. No blood background subtraction was necessary. Biodistribution studies revealed tumour to blood ratios in mice were 6:1 (at 24 h) and 17:1 (at 48 h), and tumour to muscle ratios were 34:1 (at 24 h) and 40:1 (at 48 h). Rapid in vivo breakdown of _1_2_5I-PNA led to some localisation of free iodide in the ...
The effect of adriamycin in combination with radiation on the skin reactions of mouse feet has been examined under a variety of experimental conditions including: (a) hyperthermic treatment of the foot immediately following adriamycin administration, with the former given either just before or just after x irradiation, and (b) fractionated treatments of drug and radiation in a variety of sequences over an 18-day period. In the case of the most severe hyperthermic treatment, no increased radiation reactions were observed in the presence of adriamycin. However, in the case of the less severe hyperthermic treatment a small but significant increase in skin reactions was observed. In the study of fractionated drug and radiation treatments, an enhancement of reaction in those animals receiving combined modality treatment over those receiving radiation alone was seen in those groups where the initiation of drug treatment succeeded the initiation of radiation treatment by ...
Abstract in english The tegument surface of the adult schistosome, bounded by a normal plasma membrane overlain by a secreted membranocalyx, holds the key to understanding how schistosomes evade host immune responses. Recent advances in mass spectrometry (MS), and the sequencing of the Schistosoma mansoni transcriptome/genome, have facilitated schistosome proteomics. We detached the tegument from the worm body and enriched its surface membranes by differential extraction, before subjecting t (more) he preparation to liquid chromatography-based proteomics to identify its constituents. The most exposed proteins on live worms were labelled with impearmeant biotinylation reagents, and we also developed methods to isolate the membranocalyx for analysis. We identified transporters for sugars, amino acids, inorganic ions and water, which confirm the importance of the tegument plasma membrane in nutrient acquisition and solute balance. Enzymes, including phosphohydrolases, esterases and ...
Ultra-high resolution radiographs can be obtained using synchrotron X-rays. A collaboration team consisting of K-JIST, POSTECH and YUMC has recently commissioned a new beamline (5C1) at Pohang Light Source (PLS) in Korea for medical applications using phase contrast radiology. Relatively simple image acquisition systems were set up on 5C1 beamline, and imaging studies were performed for resolution test patterns, mammographic phantom, and animals. Resolution test patterns and mammographic phantom images showed much better image resolution and quality with the 5C1 imaging system than the mammography system. Both fish and mouse images with 5C1 imaging system also showed much better image resolution with great details of organs and anatomy compared to those obtained with a conventional mammography system. A simple and inexpensive ultra-high resolution imaging system on 5C1 beamline was successfully implemented. The authors were able to acquire ultra-high resolution ...
The uncoupling protein (UCP) is a proton/anion transporter found in the inner mitochondrial membrane of brown adipocyte. Although UCP has nor been detected in mitochondria from any other tissue, it shares structural and catalytic properties with several other mitochondrial carrier proteins. Although UCP was discovered only recently it is one of the most extensively studied mitochondrial carrier proteins.More recently, the mouse, rat, and human genes encoding for UCP have been isolated and sequenced. The availability of these various tools has led to several significant observations. UCP gene expression is strongly controlled at the level of transcription by signals that are activated after the stimulation of brown adipocytes by norepinephrine. The comparison of UCP gene with the genes encoding the adenine nucleotide translocator revealed the existence of structural and evolutionary homologies. Moreover, in humans the UCP gene and one form of adenine nucleotide ...
Micropatterned materials were obtained by a controlled laser ablation of a photoimmobilised homogeneous layer of hyaluronic acid (Hyal) and its sulphated derivative (HyalS). The photoimmobilisation was performed by coating the polysaccharide, adequately functionalised with a photoreactive group, on aminosilanised glass substrate and immobilising it on the surface under UV light. Hyal or HyalS photoimmobilised samples were then subjected to laser ablation with wavelengths in the UV regions in order to drill the pattern. Four different patterns with stripes of 100, 50, 25 and 10 {mu}m were generated. A chemical characterisation by attenuated total reflection/Fourier transform infrared (ATR/FT-IR) and time of flight-secondary ions mass spectrometry (TOF-SIMS) confirmed the success of the laser ablation procedure and the presence of alternating stripes of polysaccharide and native glass. The exact dimensions of the stripes were determined by atomic force microscopy. The analysis of cell ...
Parkinson's disease (PD) is the most common neurodegenerative movement disorder. Mutations in PTEN-induced kinase 1 (PINK1) are a frequent cause of recessive PD. Autophagy, a pathway for clearance of protein aggregates or impaired organelles, is a newly identified mechanism for PD development. However, it is still unclear what molecules regulate autophagy in PINK1-silenced cells. Here we report that autophagosome formation is promoted in the early phase in response to PINK1 gene silencing by lentivirus transfer vectors expressed in mouse striatum. Reduced PP2A activity and increased phosphorylation of PP2A at Y307 (inactive form of PP2A) were observed in PINK1-knockdown dopaminergic cells and striatum tissues. Treatment with C2-ceramide (an agonist of PP2A) reduced autophagy levels in PINK...
Although it has been established that lead is transferred in milk from mother to suckling offspring, the physiological processes and parameters involved are not well understood. Single i.v. doses (0.2 mg/kg) or p.o. doses (2 mg/kg) of radiolabeled lead were administered to lactating and nonlactating female mice, and lead concentrations in blood, plasma, and milk were determined during a 21-day period. Large differences in lead elimination were observed between lactating and nonlactation mice. A significant fraction (25%) of the initial maternal dose (absorbed dose) was transferred to the suckling pups. The ratio of lead concentration in milk to lead concentration in plasma was found to be nearly constant over time. However, the milk-to-blood concentration ratios decreased during the same period. Furthermore, the concentration of lead in milk exceeded the plasma concentration by a factor of approximately 25, indicating that there is a physiological process(es) which establishes a large ...
Glycosaminoglycan synthesis by two subpopulations of a mouse mammary tumor cell line was compared. The two sublines express distinctly different growth characteristics in vitro and in vivo which indicate differences in growth regulation. Newly made glycosaminoglycans were recovered from the culture media, the cell surfaces, and residual cellular material. The cell population which grows more aggressively in vivo (+SA subline, a subline that grows in soft agarose) incorporated about 8 times more (/sup 14/C)glucosamine per cell into total glycosaminoglycans than did the slower-growing population (-SA subline, which does not grow in soft agarose). Appropriate control experiments indicated that the apparent difference in rates of synthesis was not due to discrepancies in glucosamine uptake. The main residual cellular molecule labeled was heparan sulfate, but the predominant molecule at the cell surface and in the culture fluid was hyaluronic acid. Overall, +SA cells ...
Monoclonal antibodies (MAbs) 19-9 and 73-3 specific for human colon adenocarcinoma were labelled with a high number of gadolinium atoms. Twenty five DTPA were chelated per MAb, with only slight loss of immunoreactivity. The NMR contrast agent Gd-25 DTPA-MAb 19-9 or 73-3 ((Gd) 17 mumole/kg, (MAb) 60 microM) was injected into nude mice bearing human colon adenocarcinoma (SW948). Tumors were removed 24 hr after injection and T1 was measured in vitro. T1 relaxation time varied according to MAb specificity against tumour targets; T1 decreased 20% for MAb 19-9 and MAb 73-3 with SW948 tumor. Imaging was performed with this model. Very good contrast was obtained 24 hr after Gd-25 DTPA-MAb injection.
Through DNA methylation, histone modifications, and small regulatory RNAs the epigenome systematically controls gene expression during development, both in utero and throughout life. The epigenome is also a very reactive system; its labile nature allows it to sense and respond to environmental perturbations to ensure survival during fetal growth. This pliability can lead to aberrant epigenetic modifications that persist into later life and induce numerous disease states. Endocrine-disrupting compounds (EDCs) are ubiquitous chemicals that interfere with growth and development. Several EDCs also interfere with epigenetic programming. The investigation of the epigenotoxic effects of bisphenol A (BPA), an EDC used in the production of plastics and resins, has further raised concern over the impact of EDCs on the epigenome. Using the Agouti viable yellow (A(vy)) mouse model, dietary BPA exposure was shown to hypomethylate both the A(vy) and the Cabp(IAP) metastable ...
Abnormal intracellular deposition of aggregated ?-synuclein is the characteristic feature of a number of neurological disorders, including Parkinson's disease (PD). Although ?-synuclein is typically known as a cytosolic protein, a small amount is secreted by exocytosis in both monomeric and aggregated forms. The extracellular forms of ?-synuclein in human body fluids, such as cerebrospinal fluid (CSF) and blood plasma, might be a diagnostic target for PD and related diseases. Here, we characterized a new set of monoclonal antibodies against ?-synuclein, and using different combinations of antibodies, we established ELISA systems to specifically detect human ?-synuclein, mouse and human ?-synuclein together, and multimeric forms of ?-synuclein in biological samples. By employing the Tyramide signal amplification method, the sensitivity of the assay was significantly improved to detect a concentration as low as ?12.5 pg/ml. These assays might be useful tools for ...
Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 10/sup 7/ cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 10/sup 6/ re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 10/sup 7/ cells per flask. Based on these results, a possibility that a stimulator of stem cell proliferation, released from irradiated stromal cells, is cancelled by an inhibitory factor produced by irradiated or unirradiated haemopoietic cells is postulated.
Rat lung and liver microsomes did not undergo lipid peroxidation in the absence of iron when incubated with NADPH and concentrations of paraquat ranging from 10/sup -7/ to 10/sup -2/ M. Paraquat also did not stimulate rat liver and lung microsomal peroxidation induced by added iron and NADPH, and was inhibitory at concentrations above 10 ..mu..M. Similarly, no stimulation of peroxidation was produced by paraquat in rabbit or human lung microsomes; however, under similar conditions, paraquat enhanced NADPH/iron-dependent peroxidation in mouse lung and liver microsomes obtained from rats sacrificed at 12, 18, and 24 hr following a lethal dose of paraquat (50 mg/kg, ip), there was no loss of vitamin E or increase in susceptibility to in vitro peroxidation which would be expected if lipid peroxidation had occurred in vivo although extensive lung damage developed during this time period. These results indicate that paraquat does not cause pulmonary toxicity by ...
Abstract Polycystic kidney diseases (PKD) are inherited disorders characterized by fluid-filled cysts primarily in the kidneys. We previously reported differences between the expression of Cux1, p21, and p27 in the cpk and Pkd1 null mouse models of PKD. Embryonic lethality of Pkd1 null mice limits its study to early stages of kidney development. Therefore, we examined mice with a collecting duct specific deletion in the Pkd1 gene. Cux1 was ectopically expressed in the cyst lining epithelial cells of newborn, P7 and P15 Pkd1CD mice. Cux1 expression correlated with cell proliferation in early stages of cystogenesis, however, as the disease progressed, fewer cyst lining cells showed increased cell proliferation. Rather, Cux1 expression in late stage cystogenesis was associated with increased ...
Exercise training associated with robust conditioning can be useful for the study of molecular mechanisms underlying exercise-induced cardiac hypertrophy. A swimming apparatus is described to control training regimens in terms of duration, load, and frequency of exercise. Mice were submitted to 60- vs 90-min session/day, once vs twice a day, with 2 or 4% of the weight of the mouse or no workload attached to the tail, for 4 vs 6 weeks of exercise training. Blood pressure was unchanged in all groups while resting heart rate decreased in the trained groups (8-18%). Skeletal muscle citrate synthase activity, measured spectrophotometrically, increased (45-58%) only as a result of duration and frequency-controlled exercise training, indicating that endurance conditioning was obtained. In groups which received duration and endurance conditioning, cardiac weight (14-25%) and myocyte dimension (13-20%) increased. The best conditioning protocol to promote physiological ...
Bone morphogenetic protein (BMP)-4 has a crucial role on primordial germ cells (PGCs) development in vivo which can promote stem cell differentiation to PG-like cells. In this study, we investigated the expression of Mvh as one of the specific genes in primordial germ cells after treatment with different doses of BMP4 on bone mesenchymal stem cells (BMSCs)-derived PGCs. Following isolation of BMSCs from male mouse femur and tibia, cells were cultured in medium for 72?h. Passage 4 murine BMSCs were characterized by CD90, CD105, CD34, and CD45 markers and osteo-adipogenic differentiation. Different doses of BMP4 (0, 0.01, 0.1, 1, 5, 25, 50, and 100?ng/ml) were added to BMSCs for PGCs differentiation during 4-days culture. Viability percent, proliferation rates, and expression of Mvh gene wer...
Two overlapping cDNA clones encoding human DNA topoisomerase II were identified by two independent methods. In one, a human cDNA library in phage {lambda} was screened by hybridization with a mixed oligonucleotide probe encoding a stretch of seven amino acids found in yeast and Drosophila DNA topoisomerase II; in the other, a different human cDNA library in a {lambda}gt11 expression vector was screened for the expression of antigenic determinants that are recognized by rabbit antibodies specific to human DNA topoisomerase II. The entire coding sequences of the human DNA topoisomerase II gene were determined from these and several additional clones, identified through the use of the cloned human TOP2 gene sequences as probes. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is encoded by a single-copy gene. The location of the gene was mapped to chromosome 17q21-22 by in situ hybridization of a cloned fragment to metaphase chromosomes ...
The recently described retinoid X receptors (RXRs) respond to the novel retinoid 9-cis-retinoic acid and also serve as heterodimeric partners for the vitamin D, thyroid hormone, and retinoic acid receptors (VDR, TR, and RAR, respectively). In this work, the authors report high-resolution localization of the human RXR genes within cytogenetic bands and also within a standard reference map of cosmid DNA markers on human chromosomes. They have determined the location of the human RXR genes by pairwise hybridization of the RXR cosmids and reference markers, using fluorescence in situ hybridization. They localized (i) RXR[alpha] (RXRA) to chromosome 9 band q34.3; (ii) RXR[beta] (RXRB) to chromosome 6 band 21.3; and (iii) RXR[gamma] (RXRG) to chromosome 1 band q22-q23. Six retinoid-responsive transcription factors have been identified so far, including three retinoic acid receptors in addition to the three RXRs. Interestingly, each of these receptors in human and mouse ...
This study was undertaken to investigate the effects of neonatal asphyxia on brain development, with special reference to the kinetics of neuronal proliferation by using autoradiography. For 30 minutes, two-day-old suckling mice, Jcl:ICR strain, were put into a chamber which was constantly flushed with 100% CO_2 gas. After the exposure to asphyxia, 29% of the mice survived. Cell cycle studies were carried out at two days and at seven days on the external matrix cells, the precursor of the granule cells, at the external granular layer of the cerebellum from CO_2-exposed and control mice by "3H-thymidine autoradiography. At two days the generation time of the control mice was about 15 hours, whereas that of the asphyxiated mice was about 17 hours. The prolongation of the generation time in the asphyxiated mice was caused mainly by a delay in the G2 phase. This prolongation was apparent for about five days and thereafter growth caught up. These results suggest that neonatal asphyxia has ...
A technique for delivering genes carried by recombinant retroviruses into specific cell types could have numerous applications in oncology, developmental biology, and gene therapy. As a first step toward this remote goal the authors designed a procedure allowing in vitro cell targeting by retroviruses. Biotinylated antibodies against the viral envelope protein on one side, and against specific cell membrane markers on the other side, were bridged by streptavidin and used to link the virus to the host. The method was successfully used to infect human cells with ecotropic murine retroviruses by means of major histocompatibility complex class I and class II antigens and appears easily adaptable to other cell, membrane markers. Moreover, the sequential protocol they design, although allowing infection of human cells, requires less stringent safety constraints than would handling of amphotropic virus stocks.
Computers have a direct impact on our lives nowadays. Human's interaction with the computer has modified with the passage of time as improvement in technology occurred the better the human computer interaction became. Today we are facilitated by the operating system that has reduced all the complexity of hardware and we undergo our computation in a very convenient way irrespective of the process occurring at the hardware level. Though the human computer interaction has improved but it's not done yet. If we come to the future the computer's role in our lives would be a lot more rather our life would be of the artificial intelligence. In our future the biggest resource would be component of time and wasting time for a key board entry or a mouse input would be unbearable so the need would be of the computer interaction environment that along with the complexity reduction also minimizes the time wastage in the human computer interaction. Accordingly in our future the ...
Pyrrolo[2,1-c][1,4]benzodiazepine (PBD) chemicals are antitumor antibiotics inhibiting nucleic acid synthesis. An indole carboxylate-PBD hybrid with six-carbon spacer structure (IN6CPBD) has been previously demonstrated to induce melanoma cell apoptosis and reduce metastasis in mouse lungs. This study aimed at investigating the efficacy of the other hybrid compound with four-carbon spacer (IN4CPBD) and elucidating its anti-metastatic mechanism. Human melanoma A375 cells with IN4CPBD treatment underwent cytotoxicity and apoptosis-associated assays. Transwell migration assay, Western blotting, and ELISA were used for mechanistic study. IN4CPBD exhibited potent melanoma cytotoxicity through interrupting G1/S cell cycle progression, increasing DNA fragmentation and hypodipoidic DNA contents, a...