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Folate, also known as vitamin B9, is an essential cofactor for a variety of enzymes and plays a crucial role in many biological processes. We previously reported that plastidial folate prevents starch biosynthesis triggered by the influx of sugar into non-starch-accumulating plastids, such as etioplasts, and chloroplasts under darkness; hence the loss of plastidial folate induces the accumulation of starch in plastids. To understand the molecular mechanism underlying this phenomenon, we screened our in-house chemical library and searched their derivatives to identify chemicals capable of inducing starch accumulation in etioplasts. The results revealed four chemicals, compounds #120 and #375 and their derivatives, compounds #120d and #375d, respectively. The derivative compounds induced starch accumulation in etioplasts and suppressed hypocotyl elongation in dark-grown Arabidopsis seedlings. They also inhibited the post-germinative growth of seedlings under illumination. All four chemicals contained the sulfonamide group as a consensus structure. The sulfonamide group is also found in sulfa drugs, which exhibit antifolate activity, and in sulfonylurea herbicides. Further analyses revealed that compound #375d induces starch accumulation by inhibiting folate biosynthesis. By contrast, compound #120d neither inhibited folate biosynthesis nor exhibited the herbicide activity. Protein and metabolite analyses suggest that compound #120d abrogates folate-dependent inhibition of starch accumulation in etioplasts by enhancing starch biosynthesis., (© The Author(s) 2023. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Chemotherapies have limited efficacy in pancreatic cancer (PC) and biliary tract cancer (BTC), underscoring the need for new regimens. Recently, tumor-agnostic approaches have been developed for some targeted therapies in advanced solid tumors; however, the frequency of alterations by clinical and genomic background is unclear in PC and BTC., Methods: To assess the frequencies of druggable gene alterations and investigate new potential therapeutic targetable genomic alterations, advanced PC and BTC patients were tested with comprehensive genomic profiling at Foundation Medicine during the course of clinical care., Results: A total of 16 913 PC patients and 3031 BTC patients were available for analyses, and frequencies of genomic alterations were stratified by age (≥40 years or <40 years), microsatellite instability status, tumor mutational burden status (high ≥10 or low <10 Muts/Mb), and select genomic alterations. Alterations in BRCA2, BRAF, ERBB2, CDK12, PIK3CA, FGFR2, EGFR, and other potential targets were seen across cohorts, with enrichment observed within particular subsets such as in PC patients lacking a KRAS mutation. In BTC patients, the rate of ERBB2 amplification was statistically significantly higher in the tumor mutational burden-high population (23.3% vs 13.7%). Interestingly, CDK12 rearrangement was observed in BTC patients with ERBB2 amplification tumors. In patients younger than 40 years, FGFR2 rearrangement (4%) was observed in PC: GATA6 amplification (11.1%) and rearrangement of BRAF (2.8%)FGFR2 (5.6%) was observed in BTC patients., Conclusions: We identified an appreciable frequency of immunotherapy biomarkers and targetable gene alterations in both PC and BTC, with notable frequencies in PC samples lacking KRAS mutations and children or adolescent and young adult populations, that should encourage comprehensive genomic profiling testing., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Castration-resistant prostate cancer shows resistance to not only androgen deprivation therapy (ADT) but also X-ray therapy. On the other hand, carbon ion beams have a high biological effect and are used for various cancers showing resistance to X-ray therapy. The purposes of this study are to clarify the difference in the sensitivity of Castration-resistant prostate cancer to X-ray and carbon ion beams and to elucidate the mechanism. The androgen-insensitive prostate cancer cell line LNCaP-LA established by culturing the androgen-sensitive prostate cancer cell line LNCaP for 2 years in androgen-free medium was used for this study. First, colony formation assays were performed to investigate its sensitivity to X-ray and carbon ion beams. Next, DNA mutation analysis on 409 cancer-related genes and comprehensive transcriptome analysis (RNA-seq) were performed with a next-generation sequencer. Lethal dose 50 values of X-rays for LNCaP and LNCaP-LA were 1.4 Gy and 2.8 Gy, respectively (P < 0.01). The Lethal dose 50 values of carbon ion beams were 0.9 Gy and 0.7 Gy, respectively (P = 0.09). On DNA mutation analysis, AR mutation was observed specifically in LNCaP-LA. From RNA-seq, 181 genes were identified as differentially expressed genes (DEGs; FDR <0.10, P < 0.00076) between LNCaP and LNCaP-LA. Function analysis suggested that cell death was suppressed in LNCaP-LA, and pathway analysis suggested that the NRF2-pathway involved in intracellular oxidative stress prevention was activated in LNCaP-LA. LNCaP-LA showed X-ray resistance compared to LNCaP and sensitivity to carbon ion beams. The AR mutation and the NRF2-pathway were suggested as causes of resistance., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Endoscopic duodenal stent placement is an alternative technique to gastrojejunostomy for gastric outlet obstruction due to pancreatic cancer. We compared the efficacy of endoscopic duodenal stent placement with that of gastrojejunostomy for treating patients with pancreatic cancer who are candidates for intensive combination chemotherapies as the first line of treatment., Methods: This retrospective observational study included 100 patients from 18 institutions in Japan. Inclusion criteria were as follows: (1) cytologically or histologically confirmed adenocarcinoma of the pancreas, (2) good performance status, (3) gastric outlet obstruction scoring system score of 0-1 and (4) no history of treatment for pancreatic cancer., Results: There was no significant difference in the background characteristics of patients in the endoscopic duodenal stent placement (n = 57) and gastrojejunostomy (n = 43) groups. The median overall survival in the endoscopic duodenal stent placement and gastrojejunostomy groups was 5.9 and 6.0 months, respectively. Clinical success was achieved in 93 cases; the median time to food intake resumption was significantly shorter in the endoscopic duodenal stent placement group (median: 3 days, n = 54) than in the gastrojejunostomy group (median: 5 days, n = 43). Chemotherapy was introduced in 63% of the patients in both groups after endoscopic duodenal stent placement or gastrojejunostomy. Chemotherapy was started earlier in the endoscopic duodenal stent placement group (median: 14 days) than in the gastrojejunostomy (median: 32 days) group., Conclusions: Endoscopic duodenal stent placement showed similar or better clinical outcomes than gastrojejunostomy. Thus, it might be a promising option in patients with good performance status., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Carbon-ion therapy by layer-stacking irradiation for static targets has been practised in clinical treatments. In order to apply this technique to a moving target, disturbances of carbon-ion dose distributions due to respiratory motion have been studied based on the measurement using a respiratory motion phantom, and the margin estimation given by the square root of the summation Internal margin2+Setup margin2 has been assessed. We assessed the volume in which the variation in the ratio of the dose for a target moving due to respiration relative to the dose for a static target was within 5%. The margins were insufficient for use with layer-stacking irradiation of a moving target, and an additional margin was required. The lateral movement of a target converts to the range variation, as the thickness of the range compensator changes with the movement of the target. Although the additional margin changes according to the shape of the ridge filter, dose uniformity of 5% can be achieved for a spherical target 93 mm in diameter when the upward range variation is limited to 5 mm and the additional margin of 2.5 mm is applied in case of our ridge filter. Dose uniformity in a clinical target largely depends on the shape of the mini-peak as well as on the bolus shape. We have shown the relationship between range variation and dose uniformity. In actual therapy, the upper limit of target movement should be considered by assessing the bolus shape., (© The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.)

Background: The combination of the fast-metabolizing alcohol dehydrogenase-1B (ADH1B*2 allele) and inactive heterozygous aldehyde dehydrogenase-2 (ALDH2*1/*2) increases susceptibility to macrocytic anemia and leukocytopenia in alcoholics due to severe acetaldehydemia. More than half of Japanese drinkers with esophageal cancer have this genotype combination., Methods: To assess the recovery of hematologic abnormalities after drinking cessation, changes in blood erythrocyte indices and leukocyte count during 8-week hospital stay were evaluated in 925 Japanese alcoholic men. We used four categories in ascending order for high blood acetaldehyde exposure from drinking: A, ADH1B*1/*1 plus ALDH2*1/*1; B, ADH1B*2 plus ALDH2*1/*1; C, ADH1B*1/*1 plus ALDH2*1/*2; and D, ADH1B*2 plus ALDH2*1/*2., Results: Mean values of hemoglobin and hematocrit were the lowest, and those of mean corpuscular volume (MCV) were markedly the highest in the D group on admission, and returning toward normal after abstinence, but the inter-group differences remained significant throughout the 8 weeks. The mean leukocyte count was the lowest in the D group on admission, but increased during 4-week abstinence when the inter-group differences were no longer significant. Frequencies of MCV ≥110 fl (50.5%), hemoglobin levels <11.5 g/dL (32.7%), hemoglobin levels <10.0 g/dL (9.9%) and leukocytopenia <4000/μL (22.8%) were the highest in the D group on the admission day and decreased at the 4-week abstinence (28.7%, 18.8%, 4.0% and 7.9%, respectively). The inter-group differences in frequencies of the severe anemia and leukocytopenia disappeared after 4-week abstinence., Conclusions: Drinking cessation before surgery and/or chemoradiation treatment for esophageal cancer may be effective for recovery from anemia and leukocytopenia in drinkers belonging to the D group., (© The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Aims: Alcohol consumption increases the risk of colorectal adenoma and cancer. The fecal immunochemical test (FIT) is a widely used screening method for detecting colorectal neoplasia. We evaluated the results of screening and risk factors for colorectal neoplasia in individuals with alcohol dependence., Methods: Total colonoscopic screening was performed for 1006 Japanese men with alcohol dependence (462 FIT-positive and 544 FIT-negative). Advanced neoplasia was defined as neoplasia ≥10 mm, villous or tubulovillous adenoma, high-grade adenoma, or carcinoma., Results: The detection rates for non-advanced adenoma, advanced neoplasia and intramucosal or invasive carcinoma were 38.7%, 39.4% and 9.7% for the FIT-positive group, and 33.3%, 10.8% and 2.2% for the FIT-negative group, respectively. Advanced neoplasia, especially carcinoma, was detected more frequently in the distal colon than in the proximal colon in the FIT-positive group. The respective multivariate odds ratios (ORs; 95% confidence interval) for non-advanced adenoma and advanced neoplasia were 2.83 (2.06–3.88) and 9.13 (6.19–13.5) for a positive FIT (vs. negative), 1.68 (1.39–2.02) and 1.83 (1.45–2.30) for age (per +10 years), 1.54 (1.06–2.23) and 1.88 (1.17–3.03) for current smoking (vs. non-smokers), and 1.35 (0.96–1.92) and 1.59 (1.02–2.48) for the presence of marked macrocytosis (mean corpuscular volume ≥106 fl vs. <106 fl). Genetic polymorphisms of alcohol dehydrogenase-1B and aldehyde dehydrogenase-2 did not affect the risk of colorectal neoplasia., Conclusion: The detection rate for advanced colorectal neoplasia was extremely high in the FIT-positive group but remained high even in the FIT-negative group. An older age, smoking and macrocytosis were predictors of advanced colorectal neoplasia., Short Summary: Total colonoscopic screening was performed for 1006 Japanese alcoholic men (462 fecal immunochemical test [FIT]-positive and 544 FIT-negative). The detection rate for advanced colorectal neoplasia was extremely high in the FIT-positive group (39.4%) and high in the FIT-negative group (10.8%). Ageing, smoking and macrocytosis were predictors of advanced colorectal neoplasia., (© The Author 2016. Medical Council on Alcohol and Oxford University Press. All rights reserved.)

Aims: The importance of ethanol oxidation by intestinal aerobes and facultative anaerobes under aerobic conditions in the pathogenesis of ethanol-related colorectal cancer has been proposed. However, the role of obligate anaerobes therein remains to be established, and it is still unclear which bacterial species, if any, are most important in the production and/or elimination of carcinogenic acetaldehyde under such conditions. This study was undertaken to address these issues., Methods: More than 500 bacterial strains were isolated from the faeces of Japanese alcoholics and phylogenetically characterized, and their aerobic ethanol metabolism was studied in vitro to examine their ability to accumulate acetaldehyde beyond the minimum mutagenic concentration (MMC, 50 µM)., Results: Bacterial strains that were considered to potentially accumulate acetaldehyde beyond the MMC under aerobic conditions in the colon and rectum were identified and referred to as 'potential acetaldehyde accumulators' (PAAs). Ruminococcus, an obligate anaerobe, was identified as a genus that includes a large number of PAAs. Other obligate anaerobes were also found to include PAAs. The accumulation of acetaldehyde by PAAs colonizing the colorectal mucosal surface could be described, at least in part, as the response of PAAs to oxidative stress., Conclusion: Ethanol oxidation by intestinal obligate anaerobes under aerobic conditions in the colon and rectum could also play an important role in the pathogenesis of ethanol-related colorectal cancer., (© The Author 2016. Medical Council on Alcohol and Oxford University Press. All rights reserved.)

Aims: To identify determinants of hyperuricemia in alcoholics., Methods: The serum uric acid (UA) levels of 1759 Japanese alcoholic men (≥40 years) were measured on their first visit or within 3 days after admission; ADH1B and ALDH2 genotyping on blood DNA samples were performed. Dipstick urinalyses for ketonuria and serum UA measurements were simultaneously performed for 621 men on their first visit., Results: Serum UA levels of >416 μmol/l (7.0 mg/dl) and ≥535 μmol/l (9.0 mg/dl) were observed in 30.4 and 7.8% of the subjects, respectively. Ketonuria was positive in 35.9% of the subjects, and a multivariate analysis revealed that the ketosis level was positively associated with the UA level. The presence of the ADH1B*2 allele and the ALDH2*1/*1 genotype increased the odds ratio (OR; 95% confidence interval) among subjects with a high UA level of >416 μmol/l (vs. ≤416 μmol/l; 2.04 [1.58-2.65] and 1.48 [1.09-2.01], respectively) and those with a high UA level of ≥535 μmol/l (vs. ≤416 μmol/l; 2.29 [1.42-3.71] and 3.03 [1.51-6.08], respectively). The ADH1B*2 plus ALDH2*1/*1 combination yielded the highest ORs (2.86 [1.61-5.10] and 6.21 [1.49-25.88] for a UA level of >416 μmol/l and ≥535 μmol/l, respectively), compared with the ADH1B*1/*1 plus ALDH2*1/*2 combination. The presence of diabetes and the consumption of Japanese sake rather than beer were negatively associated with the UA levels., Conclusions: The faster metabolism of ethanol and acetaldehyde by the ADH1B*2 allele and ALDH2*1/*1 genotype and higher ketosis levels were associated with higher UA levels in alcoholics, while diabetes and the consumption of sake were negative determinants., (© The Author 2015. Medical Council on Alcohol and Oxford University Press. All rights reserved.)

Aims: Alcoholic ketosis and ketoacidosis are metabolic abnormalities often diagnosed in alcoholics in emergency departments. We attempted to identify determinants or factors associated with alcoholic ketosis., Methods: The subjects of this cross-sectional survey were 1588 Japanese alcoholic men (≥40 years) who came to an addiction center within 14 days of their last drink., Results: The results of the dipstick urinalyses revealed a prevalence of ketosis of 34.0% (±, 21.5%; +, 8.9%; and 2+/3+; 3.6%) in the alcoholics. Higher urine ketone levels were associated with higher serum total bilirubin, aspartate transaminase (AST), alanine transaminase and gamma-glutamyl transpeptidase levels. A multivariate analysis by the proportional odds model showed that the odds ratio (95% confidence interval) for an increase in ketosis by one category was 0.94 (0.84-1.06) per 10-year increase in age, 0.93 (0.89-0.97) per 1-day increase in interval since the last drink, 1.78 (1.41-2.26) in the presence of slow-metabolizing alcohol dehydrogenase-1B (ADH1B*1/*1), 1.61 (1.10-2.36) and 1.30 (1.03-1.65) when the beverage of choice was whiskey and shochu, respectively (distilled no-carbohydrate beverages vs. the other beverages), 2.05 (1.27-3.32) in the presence of hypoglycemia <80 mg/dl, 0.91 (0.88-0.94) per 1-kg/m(2) increase in body mass index (BMI), 1.09 (1.00-1.18) per +10 cigarettes smoked, and 2.78 (2.05-3.75) when the serum total bilirubin level was ≥2.0 mg/dl, and 1.97 (1.47-2.66) when the serum AST level was ≥200 IU/l., Conclusion: Ketosis was a very common complication and frequently accompanied by alcoholic liver injury in our Japanese male alcoholic population, in which ADH1B*1/*1 genotype, consumption of whiskey or shochu, hypoglycemia, lower BMI and smoking were significant determinants of the development of ketosis., (© The Author 2014. Medical Council on Alcohol and Oxford University Press. All rights reserved.)

Tissue factor pathway inhibitor-2 (TFPI-2) is a major inhibitor of extracellular matrix degradation. Decreases in TFPI-2 contribute to malignant tumor cell production, and TFPI-2 is a presumed tumor suppressor. TFPI-2 gene transcription is regulated by two epigenetic mechanisms: DNA methylation of the promoter and K4 methylation of histone 3 (H3). Lysine-specific demethylase 1 (LSD1) and LSD2 demethylate H3K4me2/1. LSD1 has been implicated in TFPI-2 regulation through both epigenetic mechanisms, but the involvement of LSD2 remains unknown. We prepared a monoclonal anti-LSD2 antibody that clearly distinguishes LSD2 from LSD1. Knockdown of LSD1 or LSD2 by siRNAs increased TFPI-2 protein and mRNA. Simultaneous knockdown of both LSD1 and LSD2 showed additive effects. Bisulfite sequencing revealed that CpG sites in the TFPI-2 promoter region were unmethylated. These results indicate that LSD2 also contributes to TFPI-2 regulation through histone modification, and that further studies of the involvement of LSD2 in tumor malignancy are warranted.

Aims: Genetic polymorphisms of alcohol dehydrogenase-1B (ADH1B, rs1229984) and aldehyde dehydrogenase-2 (ALDH2, rs671) affect ethanol (EtOH) metabolism and susceptibility to alcoholism., Methods: We evaluated associations between ADH1B/ALDH2 genotypes and the blood EtOH levels of 805 Japanese alcoholic men in the morning after they had drunk within the previous 34 h., Results: Age-adjusted usual alcohol consumption did not differ according to ADH1B/ALDH2 genotypes. Higher blood EtOH levels persisted for longer periods in the ADH1B*1/*1 carriers (n = 246) than in the ADH1B*2 carriers (n = 559). Blood EtOH levels did not differ by ALDH2 genotype. The blood EtOH levels ≥ 0.3 mg/ml (criterion for drunk driving in Japanese law) were observed (40% vs. 14-17%, P < 0.0001) in a higher proportion of the ADH1B*1/*1 carriers than of the ADH1B*2 carriers after a 12.1-to-18-h interval since the last drink. Multivariate analyses showed that the EtOH levels heightened by 0.500 mg/ml in the presence of ADH1B*1*1 and by 0.248 mg/ml in the presence of cirrhosis, and lowered by 0.120 mg/ml per 10-year age increase, by 0.087 mg/ml per 10-kg body-weight increase and by 0.673 mg/ml per 10-h interval since the last drink. The odds ratio (95% confidence interval) for an EtOH level ≥ 0.3 mg/ml was 3.44 (2.34-5.04) in the presence of ADH1B*1/*1, 2.01 (1.28-3.14) in the presence of cirrhosis, 0.59 (0.49-0.71) per 10-year age increase, 0.80 (0.68-0.95) per 10-kg body-weight increase and 0.10 (0.07-0.15) per 10-h interval since the last drink., Conclusion: The longer-than-expected EtOH lingering in the blood of the ADH1B*1/*1 alcoholics may exacerbate alcohol-related problems, including drunk driving.

Aims: The life-time drinking profiles of Japanese alcoholics have shown that gastrectomy increases susceptibility to alcoholism. We investigated the trends in gastrectomy and alcohol dehydrogenase-1B (ADH1B) and aldehyde dehydrogenase-2 (ALDH2) genotypes and their interactions in alcoholics., Methods: This survey was conducted on 4879 Japanese alcoholic men 40 years of age or older who underwent routine gastrointestinal endoscopic screening during the period 1996-2010. ADH1B/ALDH2 genotyping was performed in 3702 patients., Results: A history of gastrectomy was found in 508 (10.4%) patients. The reason for the gastrectomy was peptic ulcer in 317 patients and gastric cancer in 187 patients. The frequency of gastrectomy had gradually decreased from 13.3% in 1996-2000 to 10.5% in 2001-2005 and to 7.8% in 2006-2010 (P < 0.0001). ADH1B*1/*1 was less frequent in the gastrectomy group than in the non-gastrectomy group (age-adjusted prevalence: 20.4 vs. 27.6%, P = 0.006). ALDH2 genotype distribution did not differ between the two groups. The frequency of inactive ALDH2*1/*2 heterozygotes increased slightly from 13.0% in 1996-2000 to 14.0% in 2001-2005 and to 15.4% in 2006-2010 (P < 0.08). Two alcoholism-susceptibility genotypes, ADH1B*1/*1 and ALDH2*1/*1, modestly but significantly tended not to occur in the same individual (P = 0.026). The frequency of ADH1B*1/*1 decreased with ascending age groups., Conclusions: The high frequency of history of gastrectomy suggested that gastrectomy is still a risk factor for alcoholism, although the percentage decreased during the period. The alcoholism-susceptibility genotype ADH1B*1/*1 was less frequent in the gastrectomy group, suggesting a competitive gene-gastrectomy interaction for alcoholism. A gene-gene interaction and gene-age interactions regarding the ADH1B genotype were observed.

A strong association between inactive aldehyde dehydrogenase-2 (ALDH2) and risk of esophageal cancer has been demonstrated in East Asian drinkers. An alcohol flushing questionnaire asking about past and current tendency for facial flushing to occur after drinking a glass (≈180 mL) of beer predicts the presence of inactive ALDH2 among Japanese aged 40 years or older with a sensitivity and specificity of approximately 90%. We invented a health-risk appraisal (HRA) model that makes it possible to identify Japanese men who are at high risk for esophageal cancer based on their past and current alcohol flushing tendency, drinking, smoking, and intake of vegetables and fruits. Between 2008 and 2009, 2221 Japanese men aged 50 years or older filled out the HRA questionnaire before undergoing a screening examination by upper gastrointestinal endoscopy at five medical facilities. The endoscopic examination resulted in a diagnosis of esophageal cancer in 19 subjects, and 117 (5.27%) subjects had an HRA score ≥ 11. The proportion of subjects with an HRA score ≥ 11 was higher in the 50-69 age group (6.11-6.88%) than in 70-89 age group (2.84-2.86%). The esophageal cancer detection rate was 4.27% among the subjects with an HRA score ≥ 11 and only 0.67% among the other subjects. Based on a receiver operating characteristic curve analysis, when an HRA score of ≥ 9 was used for subjects aged 50-69 years and of ≥ 8 for those aged 70-89 years as the cutoff value to select individuals with a high risk for esophageal cancer, its sensitivity and false-positive rate was 52.6% and 15.2%, respectively, and the cancer detection rate was 2.91% in the high-risk group, as opposed to 0.48% in the other group. In conclusion, the high detection rates for esophageal cancer in the high-risk groups encouraged screening based on our HRA model in larger Japanese populations., (© 2012 Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.)

The purpose of this study was to compare dose reduction to the small bowel and sacral bone by two-field and four-field techniques when the common iliac lymph node region is excluded from the radiation field in external beam radiotherapy of uterine cervical cancer. Thirteen patients with cervical cancer were entered into the study. Conventional treatment plans based on bony landmarks were made with parallel-opposed two-field technique (C2F) and four-field box technique (C4F). Modified C2F (M2F) and C4F (M4F) plans of excluding the common iliac lymph node region from the conventional radiation fields were created in reference to the bifurcations of pelvic arteries in computed tomography images. For each patient, the dose volume histograms for the small bowel and sacral bone resulting from the C2F, C4F, M2F, and M4F plans were compared. The volumes were obtained at 10 levels of prescribed dose, at increments of 10%, from 5 Gy to 50 Gy. By sparing both small bowel and sacral bone, the M2F and M4F plans were significantly better than the C2F and C4F plans at any dose level (p < 0.05), respectively. In addition, the M4F plan was significantly better than the M2F plan in sparing both small bowel at 10-50% of the prescribed dose (p < 0.05) and sacral bone at 40-100% of the prescribed dose (p < 0.05). The present study suggests that modified treatment planning could be useful for selected patients for reducing small bowel complications and insufficiency fracture after radiotherapy.

For chlortetracycline biosynthesis in Streptomyces aureofaciens, the final reduction step is essential to give an antibiotic activity to its intermediate, which is catalyzed by tetracycline dehydrogenase with 7,8-dedimethyl-8-hydroxy-5-deazariboflavin (FO) as a cofactor. We identified and cloned the gene, which is essential for the biosynthesis of 6-demethyltetracycline and participates in the final step of its biosynthesis, from the genomic DNA of the 6-demethyltetracycline producer S. aureofaciens HP77. DNA sequence analysis revealed that the gene (tchA) had an open reading frame of 455 amino acids with an estimated molecular mass of 48.1 kDa. Southern hybridization analysis revealed that the tchA gene was located external to the chlortetracycline biosynthetic gene cluster in the genome. A conserved domain search of protein sequence databases indicated that TchA showed a similarity to FbiB, which is involved in the modification of FO in Mycobacterium bovis.

We have examined the 4-hydroxylation of bunitrolol in rabbit and rat liver microsomes. Significant species differences (rabbit < rat of both sexes) and sex (male > female of both species) were observed in the formation of 4-hydroxybunitrolol from racemic bunitrolol (10 microM). The 4-hydroxylation of bunitrolol racemate and enantiomers showed biphasic kinetics, a low-Km system and a high-Km system, in liver microsomes from rabbits of both sexes. There were significant differences in Km and Vmax values [(+) > (-)] for 4-hydroxylations of (+)-bunitrolol and (-)-bunitrolol in the low-K(m) system. Furthermore, the rate of clearance (Vmax/Km) was 20- to 200-fold for the low-Km system compared with the high-Km system, indicating that enzymes in the low-Km system play a major part in the rabbit liver microsomal bunitrolol metabolism. Inhibition studies using cytochrome P450 inhibitors such as quinidine, quinine, and alpha-naphthoflavone or polyclonal antibodies raised against rat P450-2D and -1A enzymes did not make clear which P450 enzymes are involved in bunitrolol 4-hydroxylation in rabbit liver microsomes. The 4-hydroxylase activity of (+)-bunitrolol was slightly higher than that of (-)-bunitrolol in separated incubations containing male rabbit liver microsomes and an enantiomer concentration of 10 microM. However, the 4-hydroxylation of (+)-bunitrolol (10 microM) was markedly suppressed in the presence of its antipode (10 microM), whereas (-)-bunitrolol 4-hydroxylation was not affected by the presence of its antipode, resulting in a change of the stereoselectivity from (+) > (-) for enantiomer to (+) < (-) for racemate. The difference in the Michaelis constants in the low-Km system, where the Km value of (-)-bunitrolol is one-eighth that of (+)-bunitrolol, is thought to cause the change in the stereoselectivity in rabbit liver microsome-mediated bunitrolol 4-hydroxylation.

By genomic Southern blot analysis, the DNA sequences homologous to the gene cluster responsible for biosynthesis of 6-demethyl-chlortetracycline in Streptomyces aureofaciens NRRL3203 were shown to be highly conserved in independent chlortetracycline- or tetracycline producing Streptomyces strains. By contrast, oxytetracycline-producing Streptomyces strains had no hybridization with the cluster DNA.

Corynebacterium glutamicum mutants lacking ATP phosphoribosyl transferase (PRT) were selected by complementation with the Escherichia coli PRT gene. The recombinant plasmid pCH13 carrying a wild type PRT gene from C. glutamicum T106 was obtained in one of the mutants, LH13. Transformants, LH13/pCH13 and T106/pCH13, had three times higher PRT specific activity than T106. The plasmid pCH99 specifying the PRT, which was desensitized to feedback inhibition by L-histidine fifty-fold higher than the wild type PRT, was derived from pCH13. L-Histidine productivity of C. glutamicum F81, was markedly decreased by pCH13, but increased twice by pCH99. In cultivation in jar fermentors, F81/pCH99 continued to accumulate L-histidine through fermentation and yielded to the titer of 22/5 g/liter, while F81 accumulated only 11.5 g/liter due to production retardation halfway through fermentation. Moreover, F81/pCH99 had a larger production rate than F81 even in its production phase. These results indicate that the yield improvement results from amplification of the highly desensitized PRT provided by pCH99.

A useful vector, pAGE103, has been developed for the expression of cDNA in animal cells using the simian virus 40 (SV40) expression signals. cDNA could be expressed easily by inserting it into the multiple cloning sites (HindIII, SalI/AccI, XbaI, BamHI, SmaI/XmaI, KpnI/Asp718, SacI and EcoRI) of the vector, which are located between the SV40 early promoter and the SV40 early RNA processing signals for splicing and polyadenylation. In addition to the above transcription unit, pAGE103 contains the replication origin of ColE1, and a dual KmR/G418R selective gene. Several unique restriction sites are located on the boundaries between the above-mentioned three components of the vector, allowing the easy substitution or insertion of other genetic elements. The human interferon-beta gene was inserted into pAGE103 and shown to be expressed transiently in COS-1 cells and stably in several animal cell lines.

An alpha-amylase [EC 3.2.1.1] from Streptomyces praecox was purified and its characteristic action, the conversion of maltotriose (G3) to maltose (G2) without appreciable formation of glucose (G1), was investigated. Isoelectric focusing or the glycogen adsorption procedure was employed after chromatography. Isoelectric focusing showed that the enzyme preparation after chromatographic separation comprises three isozymes. The preparation from the glycogen adsorption procedure showed the highest specific activity of any preparation of this enzyme ever obtained. Product analysis with uniformly labeled G3 revealed that at a high concentration (18 mM) of G3, much more G2 is produced than G1 (the product ratio G2/G1 is over 20), while at a lower concentration (10 microM) the reaction mixture was composed of nearly equimolar amounts of glucose and maltose. Based on the product analysis of reducing end-labeled G3 in addition to the above findings, the following conversion mechanism is proposed: Streptomyces alpha-amylase catalyzes transglycosylation to produce maltotetraose (G4) as a transient product which is immediately degraded into two molecules of G2 by a subsequent hydrolytic reaction, i.e., two molecules of G3 are converted into three molecules of maltose without appreciable formation of glucose.

O-alpha-D-Glucopyranosyl-(1 leads to 4)-O-6-deoxy-6-iodo-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose (6'-MT), O-alpha-D-glucopyranosyl-(1 leads to 4)-6-deoxy-6-iodo-D-glucopyranose (6-M), and O-6-deoxy-6-iodo-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose (6'-M) were prepared and their inhibitory action against Taka-amylase A [EC 3.2.1.1, alpha-1, 4-glucan 4-glucanohydrolase, Aspergillus oryzae] was investigated. The inhibitor constants of 6'-MT and 6'-M were 10 mM and 54 mM, respectively, and both inhibitors showed mixed-type inhibition. 6-M scarcely inhibited the enzyme action.