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Ammonia is a metabolite of amino acids in dietary proteins. Excess ammonia is toxic to the man body and causes central nervous system dysfunctions. Therefore, it is catabolized into urea, a non-toxic substance, by the urea cycle in the liver. Measurements of blood ammonia levels are used to clinically detect liver dysfunctions; however, the methods currently used to assess ammonia levels have a number of limitations and require complex technical methods as well as expensive analytical instruments. In the present study, we attempted to develop a quick and easy method to detect ammonia using a spectrophotometer. We observed color changes and analyzed the absorption spectrum of aqueous ammonia after the addition of phenol and sodium hypochlorite pentahydrate (NaOCl·5H2O), which is a strong oxidant. We also examined the oxidation reaction of ammonia using liquid chromatography time-of-flight mass spectrometry (LC/TOF-MS). The results obtained showed that aqueous ammonia turned blue in color and showed unique absorption and mass spectra following the addition of phenol and NaOCl·5H2O. This spectrophotometric method may enable ammonia to be detected in sample solutions without expensive analytical instruments or complex methods. アンモニアは，飲食物中のタンパク質に含まれるアミノ酸が体内で代謝される過程で生成される．しかし，過剰なアンモニアは人体にとって毒性が高く，中枢神経系障害を引き起こす．そのため，アンモニアは肝臓における尿素サイクルの働きにより，毒性のない尿素に代謝され尿中に排泄される．このように，アンモニアは肝臓で代謝されるため，血中アンモニア濃度は肝機能を反映する指標の一つとして利用されているが，現在のアンモニア測定法は煩雑な手技や高価な分析装置を必要とする等の制限がある．本研究では，分光光度計を用いた簡易・迅速なアンモニア測定法の開発を目的とし，強力な酸化剤である次亜塩素酸ナトリウム五水和物（NaOCl·5H2O）およびフェノールをアンモニア水に添加後，色調変化の観察や分光法により吸光度を測定した．さらに，液体クロマトグラフィー飛行時間型質量分析（LC/TOF-MS）によりアンモニアの発色反応を解析した．本研究により，フェノールおよびNaOCl·5H2Oを添加したアンモニア水は青色に変化し，特徴的な吸光度およびマススペクトルを示すことが明らかとなった．以上の結果から，高価な分析装置や煩雑な手技を必要とすることなく，検体中のアンモニアを簡易に測定する検査法の開発には，本法が有用である可能性が示唆された．

To establish the best technique for thoracoscopic pneumonectomy in the rat and to analyze the differences in perioperative immune response between open and video-assisted thoracoscopic surgery (VATS) in a rat model.The four experimental groups studied were as follows: VATS pneumonectomy, open pneumonectomy, thoracoscopic observation, and open observation. We measured the immunocyte counts and serum cytokine levels postoperatively in each group.The CD3+, CD4+, and CD8+ lymphocyte counts were decreased significantly 12-24 h postoperatively in all groups. Immunosuppression peaked later in the open approach groups than in the VATS groups. The interleukin-6 level was significantly higher in the open approach groups than in the VATS groups.From the viewpoint of immunity, in this rat model VATS was less invasive than open surgery, and open surgery caused greater immunosuppression than VATS, irrespective of organ resection.

症例は16歳, 男性.既往歴として4歳時に漏斗胸に対して胸骨翻転術を施行され, 14歳時にMarfan症候群と診断された.1994年に右自然気胸に対し胸腔鏡下肺部分切除術を施行した.1996年2月に右気胸を再発し保存的に加療したが, 同年4月に右気胸を再々発し, 小開胸下に肺部分切除術を施行した.1997年2月15日に左背部痛と呼吸困難が出現し, 当科を受診した.胸部レントゲン写真にて左自然気胸と診断した.胸腔ドレーンを留置して保存的に加療するも改善しないため, 2月20日胸腔鏡下手術を施行した.肺尖部にブラが多発しており, これを切除した.Marfan症候群は気胸の合併率が高く, 本例のように体格の成長に伴って気胸を繰り返し再発することもあり, 注意深い経過観察が必要と思われた.

p16(INK4a) is a tumor suppressor gene frequently inactivated by aberrant promoter hypermethylation. In the present study, p16(INK4a) methylation was evaluated in non-small cell lung cancer (NSCLC) using a quantitative assay and the clinical significance of the methylation was explored.A total of 244 tumor samples from formalin-fixed paraffin-embedded archives were examined in this study. p16(INK4a) methylation was analyzed by the fluorescence-based, real-time methylation-specific PCR assay, MethyLight. The quantitative methylation value was expressed as the percentage of methylated reference (PMR).The median level of p16(INK4) methylation was 0.55 PMR (range 0.00-503.4). The p16(INK4) methylation value was significantly higher in males (p = 0.005) and in squamous cell carcinoma (p = 0.018). Prognostic analysis using the Cox proportional hazard model showed that the p16(INK4a) methylation value was a significant prognostic factor (odds ratio, 1.005; 95% CI, 1.003 to 1.008; p0.0001). The p16(INK4a) methylation value remained a significant prognostic factor (p = 0.0004) in multivariate analysis including age, gender, histological type and clinical stage. Specimens were then classified into hypermethylated or non-hypermethylated groups based on the p16(INK4a) methylation value using various cut-offs from 1 to 100 PMR. There was no significant difference in prognosis between the two groups using a cut-off value of 1 PMR. On the other hand, there was a significant difference using 6 PMR or more as the cut-off value (p0.01).These results provide clear evidence for the prognostic significance of p16(INK4a) methylation in NSCLC using quantitative DNA methylation analysis. Careful assessment of DNA methylation is needed because qualitative methylation analysis may overestimate low levels of methylation, which have less clinical significance.

Thymidylate synthase (TS) and methylenetetrahydrofolate reductase (MTHFR) play important roles in folate metabolism. Previous studies have suggested that TS expression is a prognostic factor in non-small cell lung cancer (NSCLC). The TS gene has a variable number of tandem repeats (VNTR) and single nucleotide polymorphism (SNP) in the 5'-untranslated region, which are associated with TS expression. This association suggests that the TS polymorphism is a novel prognostic factor in NSCLC. In the present study, multiple genetic polymorphisms, TS VNTR, TS SNP and MTHFR C677T, were analyzed in NSCLC and compared with clinicopathological features and patients' prognoses.Genomic DNA was isolated from 294 surgically resected NSCLC tissues. The genotypes were determined by PCR and PCR-RFLP. The TS VNTR and SNP were combined, followed by functional stratification of H/H (3G/3G), H/L (2R/3G, 3G/3C) and L/L (2R/2R, 2R/3C, 3C/3C). Patients' prognoses were compared with TS and/or MTHFR genotype groups. TS was divided into the H- (H/H, H/L) and L-groups (L/L) according to functional stratification and MTHFR C677T was divided into C- (C/C) and T-groups (C/T, T/T).TS VNTR, the SNP and the TS functional type, along with MTHFR C677T, showed no significant association with clinicopathological factors. There were no differences in prognosis between each genotype or functional group when the TS and MTHFR groups were considered separately. However, we found a unique association between prognosis and the TS functional group in stage I NSCLC, taking both TS and MTHFR groups into consideration. The patients in the TS L-group survived longer than those in the H-group when limited to stage I and MTHFR C-group (p = 0.086). This relationship between the TS genotype group and prognosis was statistically significant in the subgroup of stage IB and MTHFR C-group (p = 0.030). In contrast, the patients in the TS H-group survived longer than those in the L-group when limited to stage I and MTHFR T-group (p = 0.052).The TS and MTHFR genotypes can be prognostic factors in NSCLC, where gene-gene interactions between the genotypes may occur. Further validation and investigation of the involvement of genotypes of folate metabolizing enzymes in the prognosis of NSCLC patients are required.

Background: A daily injection of glycyrrhizin (Stronger Neo-Minophagen C (SNMC) containing 40 mg glycyrrhizin in a 20 mL ampoule) lowers alanine aminotransferase (ALT) levels in patients with chronic viral hepatitis. Methods: The therapeutic effects of intermittent administration of SNMC three times a week for 12 weeks were evaluated and compared between two doses (40 and 100 mL) in a randomized clinical trial. Results: Overall, the therapeutic response was better in the 53 patients allocated 100 mL than the 59 who were allocated to have 40 mL SNMC (P = 0.0243). At the completion of SNMC treatment, ALT levels decreased more extensively in the patients on 100 mL than those on 40 mL SNMC (−29 vs−50% in comparison with the baseline value, P = 0.0002). Minor side-effects occurred in both the patients on 100 mL (20%) and those on 40 mL (12%), but they did not require any therapies. Conclusions: Intermittent SNMC would be efficient in suppressing ALT levels in patients with chronic viral hepatitis in a dose-dependent manner. Taken along with infrequent and very mild side-effects, long-term intermittent SNMC would benefit patients with chronic hepatitis by maintaining their quality of life with easier compliance. © 2002 Blackwell Publishing Asia Pty Ltd

The effect of insulin and/or glucagon on the cumulative incorporation of tritiated thymidine was studied using normal rats with post-hepatectomized regenerating livers. Although the cumulative incorporation value was low at 20 hr and increased thereafter, a significant difference was not found between control and treated rats up to 60 hr after the operation. However, when rats were distributed according to the time the incorporation reached a maximum, there was a significant difference in the distributions between control rats and rats treated with combined insulin and glucagon (P=0.0303); more rats showed maximum incorporation at earlier times after treatment. These results suggest that a combination of the two hormones accelerates DNA synthesis in post-hepatectomized regenerating liver of normal rats.