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S Masunaga

Publications and source records attributed to S Masunaga.

At least 19 recordsLinked to original sources
PubMed2006

The usefulness of a continuous administration of tirapazamine combined with reduced dose-rate irradiation using {gamma}-rays or reactor thermal neutrons.

We clarified the usefulness of the continuous administration of tirapazamine (TPZ) in combination with reduced dose-rate irradiation (RDRI) using gamma-rays or reactor thermal neutrons. Squamous cell carcinoma (SCC) VII tumour-bearing mice received a continuous administration of 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) cells. Then, they received a single intraperitoneal injection or 24 h continuous subcutaneous infusion of TPZ in combination with conventional dose-rate irradiation (CDRI) or RDRI using gamma-rays or thermal neutrons. After irradiation, the tumour cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labelling ( = quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total tumour cells was determined using tumours that were not pre-treated with BrdU. The sensitivity of both total and Q cells, especially of Q cells, was significantly reduced with RDRI compared with CDRI. Combination of TPZ increased the sensitivity of both populations, with a slightly more remarkable increase in Q cells. Furthermore, the continuous administration of TPZ raised the sensitivity of both total and Q cell populations, especially the former, more markedly than the single administration, whether combined with CDRI or RDRI using gamma-rays or thermal neutrons. From the viewpoint of solid tumour control as a whole, including intratumour Q-cell control, the use of TPZ, especially when administered continuously, combined with RDRI, is useful for suppressing the reduction in the sensitivity of tumour cells caused by the decrease in irradiation dose rate in vivo.

Animals↗
PubMed2005

The usefulness of continuous administration of hypoxic cytotoxin combined with mild temperature hyperthermia, with reference to effects on quiescent tumour cell populations.

To evaluate the usefulness of continuous administration of hypoxic cytotoxins in terms of targeting acute hypoxia in solid tumours and the significance of combination with mild temperature hyperthermia (MTH) (40 degrees C, 60 min), the cytotoxic effects of singly or continuously administered tirapazamine (TPZ) and TX-402 were examined in combination with or without MTH in vivo. Further, the effects were also analysed on total (=proliferating (P)+quiescent (Q)) and Q cell populations in solid tumours with the method for selectively detecting the Q cell response. C3H/He mice bearing SCC VII tumours received a continuous administration of 5-bromo-2'-deoxyuridine (BrdU) for 5 days to label all P cells. The tumour-bearing mice then received a single intra-peritoneal injection or 24 h continuous subcutaneous infusion of hypoxic cytotoxin, TPZ or TX-402, with or without MTH. On the other hand, to detect the changes in the hypoxic fraction (HF) in the tumours by MTH, another group of mice with or without MTH received a series of test doses of gamma-rays while alive or after tumour clamping. After each treatment, the tumour cells were isolated and incubated with a cytokinesis blocker (=cytochalasin-B) and the micronucleus (MN) frequency in cells without BrdU labelling (=Q cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total tumour cells was determined from the tumours that were not pre-treated with BrdU. The sensitivity to TX-402 was slightly higher than that to TPZ in both total and Q tumour cells. Continuous administration elevated the sensitivity of both total and Q cells, especially total cells. MTH raised the sensitivity of Q cells more remarkably than that of total cells in both single and continuous administrations. It was thought to be probably because of the higher dose distribution of hypoxic cytotoxin in intermediately hypoxic areas derived mainly from chronic hypoxia through MTH. From the viewpoint of tumour control as a whole including both total and Q tumour cells, the continuous administration of hypoxic cytotoxin combined with MTH may be useful for sensitizing tumour cells in vivo.

Animals↗
PubMed2004

Temporal trends of organochlorine pesticides in prawn (Macrobrachium nipponense) from Lake Kasumigaura, Japan, during 1978-2000.

Temporal trends of organochlorine pesticides such as beta-hexachlorocyclohexane (beta-HCH), hexachlorobenzene (HCB), and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE), were determined in freshwater prawn (Macrobrachium nipponense) collected from Lake Kasumigaura in 1978 to 2000. The organochlorine pesticides elucidated a 72.4% decrease in beta-HCH, from 42 (1978) to 11.6 ng/g fat (2000); an 89.6% decrease in HCB, from 1.64 (1978) to 0.17 ng/g fat (2000); and an 87.3% decrease in p,p'-DDE, from 97.5 (1978) to 12.4 ng/g fat (1992). After organochlorine pesticide prohibition in 1971, the declining trend of beta-HCH, HCB, and p,p'-DDE concentrations persisting in the prawns could be approximated by exponential equations.

Animals↗
PubMed2004

The usefulness of 2-nitroimidazole-sodium borocaptate-10B conjugates as 10B-carriers in boron neutron capture therapy.

We evaluated the usefulness of five new (10)B-compounds (TX-2016, TX-2017, TX-2018, TX-2041, and TX-2042) as (10)B-carriers in boron neutron capture therapy (BNCT). They are 2-nitroimidazole-sodium borocaptate-(10)B (BSH) conjugates, that is, hybrid compounds that have both hypoxic tumor cell sensitizing unit under gamma-ray irradiation, 2-nitroimidazoles, and thermal neutron-sensitizing unit, BSH. (10)B distribution analyses in tumors and blood indicated that TX-2041 has the most favorable characteristics for localizing a sufficient amount of (10)B into tumors and keeping the (10)B concentration high during neutron beam irradiation. In addition, TX-2041 showed a significantly higher radio-sensitization effect with reactor thermal neutron beams than BSH on both total (=proliferating (P) + quiescent (Q)) and hypoxia-rich Q cell populations in solid tumors. Further, TX-2041 clearly demonstrated a radio-sensitization effect with gamma-rays on both cell populations, which could never be achieved by BSH. (10)B-carriers with a hypoxic tumor cell-sensitizing effect on tumors with gamma-rays as well as the potential to selectively localize and keep (10)B in tumors, such as TX-2041, are promising for use in actual BNCT.

Animals↗
PubMed2002

Polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in livers of birds from Japan.

Concentrations of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non- and mono-ortho-chlorine-substituted polychlorinated biphenyls (dioxin-like PCBs) were measured in livers of 17 species of birds collected from Japan. Birds were grouped according to their feeding habits as granivores, piscivores, omnivores, and predators for discussions. Livers of granivores contained relatively low concentrations of PCDD/DFs (80-660 pg/g) followed in increasing order by omnivores (2,300-8,000 pg/g), piscivores (61-12,000 pg/g) and predators (480-490,000 pg/g on a fat weight basis). Especially, one species of predatory bird (mountain hawk eagle) contained elevated concentrations of PCDDs, PCDFs, and dioxin-like PCBs, and the measured concentration is one of the highest reported to date. Homolog and congener patterns of PCDDs and PCDFs varied among species; hence, the results suggested that feeding habits, specific elimination, and metabolism influence contamination pattern. Concentrations of dioxin-like PCBs were in the order of granivores (32-83 ng/g) < predators [excluding mountain hawk eagle] (32-2,500 ng/g) < piscivore (61-12,000 ng/g) < omnivores (1,800-67,000 ng/g on a fat weight basis). Mountain hawk eagle contained the highest concentration of dioxin-like PCBs (55,000 ng/g fat weight). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalents (TEQs) ranged from 53-450,000 pg/g fat weight. 23478-PeCDF, 2378-TCDD/TCDF, and PCB congeners IUPAC 126 and 77 were major contributors to TEQs in birds. To our knowledge, this is the first study of PCDD/DFs and dioxin-like PCBs in livers of several species of Japanese birds.

Animals↗
PubMed2002

Radiobiological characteristics of solid tumours depending on the p53 status of the tumour cells, with emphasis on the response of intratumour quiescent cells.

Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/mTP53) or with a neo vector as a control (SAS/neo) were inoculated subcutaneously (s.c.) into both hind legs of Balb/cA nude mice. Mice bearing tumours received 5-bromo-2'-deoxyuridine (BrdU) continuously to label all proliferating (P) cells in the tumours. The mice then received gamma-ray irradiation. Another group of mice received a series of test doses of gamma-rays while alive or after tumour clamping to obtain hypoxic fractions (HFs) in the tumours. Right after irradiation, the tumour cells were isolated and incubated with a cytokinesis blocker. The micronucleus (MN) frequency in the cells without BrdU labelling (=quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. Meanwhile, 6 h after irradiation, tumour cell suspensions obtained in the same manner were used for determining the frequency of apoptosis in the Q cells. The MN frequency and apoptosis frequency in total (P+Q) tumour cells were determined from the tumours that were not pretreated with BrdU. In total cell populations, SAS/mTP53 cells were more radioresistant than SAS/neo cells in clonogenic survival. Q tumour cells exhibited a significantly lower apoptosis and MN frequency, probably due to their much larger HF, than total cells. In both total and Q cell fractions, SAS/mTP53 cells were less susceptible to apoptosis and more susceptible to micronucleation than SAS/neo cells. Obviously, TP53 status had the potential to influence the radiosensitivity of not only the total cells, but also the Q cells. However, irrespective of the TP53 status, significant differences in radiosensitivity between total and Q tumour cells were consistently observed. From the viewpoint of tumour control as a whole, including intratumour Q tumour cell control, a treatment modality for enhancing the Q cell response has to be considered.

Animals↗
PubMed2001

Evaluation of apoptosis and micronucleation induced by reactor neutron beams with two different cadmium ratios in total and quiescent cell populations within solid tumors.

PURPOSE: Response of quiescent (Q) and total tumor cells in solid tumors to reactor neutron beam irradiation with two different cadmium (Cd) ratios was examined in terms of micronucleus (MN) frequency and apoptosis frequency, using four different tumor cell lines. METHODS AND MATERIALS: C57BL mice bearing EL4 tumors, C3H/He mice bearing SCC VII or FM3A tumors, and Balb/c mice bearing EMT6/KU tumors received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. Thirty min after i.p. injection of sodium borocaptate-10B (BSH), or 3 h after oral administration of p-boronophenylalanine-10B (BPA), the tumors were irradiated with neutron beams. The tumors without 10B-compound administration were irradiated with neutron beams or gamma-rays. This neutron beam irradiation was performed using neutrons with two different Cd ratios. The tumors were then excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the MN frequency in cells without BrdU labeling (=Q cells) was determined using immunofluorescence staining for BrdU. Meanwhile, for apoptosis assay, 6 h after irradiation, tumor cell suspensions obtained in the same manner were fixed, and the apoptosis frequency in Q cells was also determined with immunofluorescence staining for BrdU. The MN and apoptosis frequencies in total (P + Q) tumor cells were determined from the tumors that were not pretreated with BrdU. RESULTS: Without 10B-compounds, the sensitivity difference between total and Q cells was reduced by neutron beam irradiation. Under our particular neutron beam irradiation condition, relative biological effectiveness (RBE) of neutrons was larger in Q cells than in total cells, and the RBE values were larger for low Cd-ratio than high Cd-ratio neutrons. With 10B-compounds, both frequencies were increased for each cell population, especially for total cells. BPA increased both frequencies for total cells more than BSH did. Nevertheless, the sensitivity of Q cells treated with BPA was lower than that of Q cells treated with BSH. Whether based on the MN frequency or the apoptosis frequency, similar results concerning the sensitivity difference between total and Q cells, the values of RBE, and the enhancement effect by the use of 10B-compound were obtained. CONCLUSION: Apoptosis frequency, as well as the MN frequency, can be applied to our method for measuring the Q cell response to reactor neutron beam irradiation within solid tumor in which the ratio of apoptosis to total cell death is relatively high, as in EL4 tumor. The absolute radiation dose required to achieve the same endpoint for Q cells is much higher than that for total cells when combined with 10B-compound, especially with BPA.

Animals↗
PubMed2001

Polychlorinated dibenzo-p-dioxins, dibenzofurans, and polychlorinated biphenyls in human tissues, meat, fish, and wildlife samples from India.

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and non- and mono-ortho-substituted polychlorinated biphenyls (dioxin-like PCBs) were measured in tissues of humans, fishes, chicken, lamb, goat, predatory birds, and Ganges River dolphins collected from various locations in India. PCDDs/DFs were found in most of the samples analyzed with the liver of spotted owlet containing the highest concentration of 3,300 pg/g, fat wt. 2,3,7,8-Substituted PCDDs and PCDFs were found in human fattissues at concentrations ranging from 170 to 1,300 pg/g, fat wt. Concentrations of PCDDs were generally greaterthan those of PCDFs in human tissues, fishes, animal fat, and dolphin. Among fishes, meat, and wildlife samples analyzed, concentrations of PCDDs/DFs were found in the following order: country chicken < goat/lamb fat < fishes < river dolphins < predatory birds. Hepta-CDDs and OCDD were the major PCDD homologues found in humans, fishes, meat products, and dolphins. 2,3,7,8-Tetrachlorodibenzo-p-dioxin equivalents of PCDDs/DFs were greater than those of PCBs in selected fish, dolphin, and human samples. To our knowledge, this is the first report of PCDDs and PCDFs in human tissues, fishes, meat, and wildlife collected from India.

Adult↗
PubMed2001

Identifying sources and mass balance of dioxin pollution in Lake Shinji Basin, Japan.

On the basis of congener-specific analysis of dioxins in a dated sediment core, the sources and behavior of dioxins in Lake Shinji Basin, Japan, were estimated. The dioxins in the core showed that their deposition in the lake increased rapidly during the 1960s, peaked in the early 1970s, and then decreased gradually. Principal component analysis of the congener-specific data showed that three major sources existed: pentachlorophenol (PCP), chloronitrophen (CNP), and combustion. PCP and CNP are paddy field herbicides used extensively in the basin. The time trends of source contributions were estimated by multiple regression analysis using the source profiles. The results revealed that dioxin emission from PCP and CNP herbicides was high in the 1960s and the early 1970s, respectively. The contributions from PCP, CNP, and combustion in recent surface sediment were about 68, 16, and 16% in terms of total amount of dioxins. From the decreasing trend of dioxin deposition in the lake after extensive herbicide use, the amount of dioxins that accumulated in the agricultural soil in the basin was estimated to have decreased by about 2%/yr or a half-life of about 35 yr, indicating that dioxin runoff from agricultural fields would continue for a long time.

Agriculture↗
PubMed2001

Radiobiologic significance of apoptosis and micronucleation in quiescent cells within solid tumors following gamma-ray irradiation.

PURPOSE: To determine the frequency of apoptosis in quiescent (Q) cells within solid tumors following gamma-ray irradiation, using four different tumor cell lines. In addition, to assess the significance of detecting apoptosis in these cell lines. METHODS AND MATERIALS: C3H/He mice bearing SCC VII or FM3A tumors, Balb/c mice bearing EMT6/KU tumors, and C57BL mice bearing EL4 tumors received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received gamma-ray irradiation at a dose of 4--25 Gy while alive or after tumor clamping. Immediately after irradiation, the tumors were excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (= Q cells) was determined using immunofluorescence staining for BrdU. Meanwhile, 6 hours after irradiation, tumor cell suspensions obtained in the same manner were fixed. The apoptosis frequency in Q cells was also determined with immunofluorescence staining for BrdU. The MN and apoptosis frequency in total (P + Q) tumor cells were determined from the tumors that were not pretreated with BrdU. RESULTS: In total cells, SCC VII, FM3A, and EMT6/KU cells showed reasonable relationships between MN frequency and surviving fraction (SF). However, fewer micronuclei were induced in EL4 cells than the other cell lines. In contrast, a comparatively close relationship between apoptosis frequency and SF was found in total cells of EL4 cell line. Less apoptosis was observed in the other cell lines. Quiescent tumor cells exhibited significantly lower values of MN and apoptosis frequency probably due to their large hypoxic fraction, similar to total tumor cells on clamped irradiation. CONCLUSION: gamma-ray irradiation induced MN formation in SCC VII, FM3A, and EMT6/KU tumor cells, and the apoptosis was marked in EL4 cells compared with the other cell lines. Our method for detecting the Q cell response to gamma-ray irradiation using P cell labeling with BrdU and the MN frequency assay was also applicable to apoptosis detection assay.

Animals↗
PubMed2001

Dioxin and dioxin-like PCB impurities in some Japanese agrochemical formulations.

The profile and amount of dioxin impurity in agrochemicals were studied through detailed analysis of historic Japanese formulations. The chemicals analyzed include pentachlorophenol (PCP), 2,4,6-trichlorophenyl-4'-nitrophenyl ether (chloronitrofen, CNP), 2,4-dichlorophenyl-4'-nitrophenyl ether (nitrofen, NIP), tetrachloro-iso-phthalonitrile (chlorothalonil, TPN), 2-methyl-4-chloro-phenoxyacetic acid (MCP) and 2,4-dichlorophenoxyacetic acid (2,4-D). Among the six, two herbicides, PCP and CNP, produced during the 1960s and 1970s, contained very high concentrations of PCDD/DFs and TEQ. Others contained relatively low concentrations of PCDD/DFs. Dioxin-like PCB concentrations in all chemicals studied were low and their contributions to TEQ were negligible. The total dioxin emissions from the use of agrochemicals in Japan during the past 40 years (1955-1995) were estimated to be about a few hundred thousand kg of PCDD/DFs and 250 kg of WHO-TEQ from PCP and 190 x 10(3) kg of PCDD/DFs and 440 kg of WHO-TEQ from CNP. The major dioxin congeners present in PCP formulations were highly chlorinated PCDD/DFs that can be formed by the coupling of PCP and/or 2,3,4,6-tetrachlorophenol, and those in the CNP formulations were tetra- to hexa-chlorinated PCDD/DFs that can be formed from 2,4,6-trichlorophenol and/or 2,3,4,6-tetrachlorophenol.

Agriculture↗
PubMed2001

Atmospheric deposition of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in the Kanto Region, Japan.

The atmospheric bulk (dry and wet) deposition of dioxins was investigated at four locations (Tokyo, Yokohama, Tsukuba, and Tanzawa) in the Kanto region (in Japan) over one year using a stainless-steel pot. Annual average polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) deposition fluxes were estimated to be from 450 to 1300 ng/m2/yr, and the annual average TEQ fluxes from 5.7 to 17 ng-TEQ/m2/yr at the four locations. The PCDD/PCDF deposition flux was higher in winter than in summer. The deposition flux could be related to ambient temperature, particularly for less chlorinated PCDDs/PCDFs, while the deposition flux is not necessarily related to the amount of precipitation. The PCDD/PCDF deposition flux increased as the particle deposition flux increased, for the winter samples. Based on the ratio of the PCDD/PCDF deposition fluxes to the particle deposition fluxes, the contribution of the reentrainment of soil particles to the TEQ of PCDD/PCDF deposition was considered to be negligible in this region. Based on the air concentrations monitored near our deposition sampling points by the municipalities, the ratio of the annual deposition flux to the annual average air concentration was roughly estimated to be 0.082 cm/s. The range of deposition flux in the Kanto region was estimated to be from 1.5 to 31 (median: 9.8) ng-TEQ/m2/yr based on the range of air concentration data measured by the municipalities. The total annual deposition flux in the entire Kanto region was estimated to range from 50 to 900 g-TEQ/yr (median 320 g-TEQ/yr). This estimated flux was of the same order as the sum of estimated emissions from municipal solid waste incinerators and industrial waste incinerators in the Kanto region. The contributions of dioxin-like PCBs in Yokohama, Tsukuba, and Tanzawa depositions were less than 10% of the total TEQ; however, in Tokyo it was almost equal to or more than 50%.

Air Pollutants↗
PubMed2001

Chlorinated persistent organic pollutants in black-tailed gulls (Larus crassirostris) from Hokkaido, Japan.

Concentrations and patterns of several chlorinated persistent organic pollutants (POPs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) and DDTs, HCHs, CHLs and HCB were determined in black-tailed gulls (Larus crassirostris) from breeding grounds in Hokkaido, Japan. Subcutaneous fat of five adult gulls was analyzed, which had different concentrations of target compounds, whereas gull eggs contained similar concentrations of target compounds. Similar congener profiles were found between adult gulls and eggs. The concentrations of non-ortho PCBs varied from 3.4 to 13.5 ng/g lipid weight (lw) in the fat of black-tailed gulls and from 2.4 to 7.4 ng/g lw in their eggs. 2,3,7,8-PCDD/Fs occurred at relatively lower concentrations than non-ortho PCB congeners in both adult gulls and eggs. The total TEQs (toxic equivalents, PCDD/Fs+ non-ortho PCB) ranged from 0.26 to 1.0 ng/g lw in adult gulls and ranged from 0.19 to 0.58 ng/g lw in eggs.

Adipose Tissue↗
PubMed2001

Congener-specific characterization of PCDDs/PCDFs in atmospheric deposition: comparison of profiles among deposition, source, and environmental sink.

In order to examine the input of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs) from various airborne sources to environmental sinks, the atmospheric deposition of congener-specific PCDDs/PCDFs was investigated. Homologue and congener profiles of atmospheric depositions were compared with those of sources and environmental sinks to identify the relationship among atmospheric depositions, sources, and environmental sinks. Moreover, factor analysis was used to detect similarities, differences, and relationships of the variations in deposition fluxes among congeners within the same and different homologues. The results showed that the congener profiles of the atmospheric depositions were primarily determined by those of combustion emissions. Several congeners in some specific samples showed higher proportions within each homologue compared with representative depositions. This result can be partly explained by the influence of impurities in herbicides, 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP) and pentachlorophenol (PCP). The congener profiles of combustion emissions, representative depositions, and urban soils were very similar although their homologue profiles varied. This implied that PCDDs/PCDFs in the urban soils originate from the deposition of combustion emissions and that all congeners within each homologue behave identically in air and soil. Although the congener profiles of the representative depositions were different from those of the sediments in Tokyo Bay and the soil of a paddy field, the combination of congener profiles of the representative depositions and of the impurities in herbicides. CNP and PCP, can explain the congener profiles of the sediments and the paddy field. This study showed that congener-specific data are useful for source identification.

Agriculture↗
PubMed2001

Enhancement of the therapeutic outcome of radio-immunotherapy by combination with whole-body mild hyperthermia.

To enhance the effect of radio-immunotherapy for solid cancers, whole-body mild hyperthermia was added, and its effects on the pharmacokinetics of radiolabelled antibody, outcome of radio-immunotherapy, and radiosensitivity of the tumour were investigated. Nude mice bearing human colon cancer xenografts were heated to 40 degrees C for 3 or 6 h. After heating, mice received intravenous (i.v.) injections of [131I]-labelled anti-carcinoembryonic antigen (CEA) monoclonal antibody. Although 6-h heating did not alter the biodistribution of the radiolabelled antibody, and alone did not show any therapeutic effect on tumour growth, when combined with radio-immunotherapy, the therapeutic effect on tumour growth was significantly enhanced. Three-hour heating also significantly enhanced the effect of radio-immunotherapy. Colony formation assay showed that the radiosensitivity of the tumour was significantly enhanced after heating, which was achieved by a reduction of the hypoxic fraction of the tumour. In conclusion, the addition of whole-body mild hyperthermia significantly enhanced the therapeutic effect of radio-immunotherapy by increasing the radiosensitivity of the tumour.

Animals↗
PubMed2001

Polychlorinated naphthalenes, biphenyls, dibenzo-p-dioxins, and dibenzofurans as well as polycyclic aromatic hydrocarbons and alkylphenols in sediment from the Detroit and Rouge Rivers, Michigan, USA.

Sediment from the upper Detroit and lower Rouge Rivers in southeastern Michigan, USA, were analyzed to examine the distribution of polychlorinated naphthalenes (PCNs), biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) as well as polycyclic aromatic hydrocarbons (PAHs) and alkylphenolic compounds such as butylphenol, octylphenol, and nonylphenol (NP). Sediments from a non-point source location in Lake Michigan were also analyzed for target compounds. Concentrations of target compounds in the upper Detroit and lower Rouge Rivers varied considerably among locations, and notable spatial variation existed. Concentrations of PCNs and PCDDs/PCDFs in sediments from the upper Detroit and lower Rouge Rivers ranged from 0.08 to 187 ng/g and 69 to 1420 pg/g dry weight, respectively. Total PCBs, PAHs, and NP concentrations ranged from 8 to 25,000, 17 to 44,000, and < 10 to 60,000 ng/g dry weight, respectively. Concentrations of all target compounds except PCNs were significantly correlated with total organic carbon content of sediments. Similarly, concentrations of PCBs, PCDDs, and PCDFs were significantly correlated with each other. The distribution of organic contaminants in the upper reaches of the Detroit River and lower Rouge River suggested the presence of localized, but multiple, sources of contamination for each compound class. Conners Creek combined sewer overflow has been identified as one of the potential sources for the upper Detroit River, where the highest concentrations PCBs and PCDDs/PCDFs were found. Polycyclic aromatic hydrocarbon and NP concentrations were consistently high in sediment from the lower Rouge River. Analysis of data from selected locations suggested that PCNs contributed a greater proportion of the dioxin-like activity than PCBs and PCDDs/PCDFs contributed.

Benzofurans↗