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Enterovesical fistula (EVF) is a rare complication of diverticulitis, as well as Crohn's disease, intestinal malignancy, radiotherapy and trauma. EVF formation is associated with inflammation of the involved bowel segments. The current study presents the case of a 35-year-old man with non-Hodgkin's lymphoma who developed pneumaturia, fecaluria and recurrent urinary tract infections following chemotherapy, accompanied by regressive change of the lymphoma. Abdominal computed tomography scans revealed that the terminal ileum had adhered to the bladder wall. The patient underwent exploratory laparotomy and partial resection of the terminal ileum, and EVF was confirmed. Histological examination revealed an inflammatory response but no evidence of residual lymphoma. The diagnosis of EVF is occasionally difficult and requires appropriate radiographic examination. Surgical treatment is recommended. [ABSTRACT FROM AUTHOR]

This essay is a reflection on the ways we understand East Asia, as well as how East Asia is related to our knowledge construction. In spite of the personal tone, which I use strategically to formulate arguments in a carefully designed narrative flow, the article remains critical throughout and its conclusion is clear: exploration of the essence of East Asian civilization can constitute a meaningful effort to reevaluate and even restructure our current world of knowledge. [ABSTRACT FROM AUTHOR]

BACKGROUND: The polymorphic CAG repeats of the androgen receptor (AR) gene have been suggested to affect the risk of breast cancer, but the results are controversial. In addition, the relationship between patients' CAG genotype and the prognosis has not been investigated. OBJECTIVE: The purpose of this study is to access the association between the polymorphic CAG repeats and the incidence and prognosis of breast cancer. METHODS: One hundred and fifty-six breast cancer cases and 108 healthy controls from Taipei Veteran General Hospital were enrolled. The length of CAG repeats was analyzed among by means of PCR amplification. The logistic regression model was used for cross-sectional analyses of prevalent breast cancer. Furthermore, we categorized the cases according to the average length of both CAG alleles (CAGn ≥ 23 versus < 23). Outcomes were disease-free survival and mortality. The Cox proportional hazards model and Kaplan-Meier estimate were used for survival analysis. RESULTS: The median age was 56 (51-64) and 46 (37-52) in breast cancer patients and healthy controls, respectively. The median of CAGn was 22.5 (21.5-24) in study group and 23 (21.5-24) in controls. Our study showed the length of CAG repeats did not contribute to breast cancer or benign breast tumors (HR 1.01; 95% CI, 0.90-1.13). In the median follow-up of 6.59 years, we found the CAGn ≥ 23 (n = 75) could be a poor prognosis (adjust HR, 3.08; 95% CI, 1.42-6.67, p = 0.004). CONCLUSION: The CAG polymorphism is not associated with development of breast cancer, but patients with more CAG repeats of the AR gene are prone to poor prognoses. [ABSTRACT FROM AUTHOR]

Preparation of new types of highly functional benzofurans, benzothiophenes, and indoles is realized via intramolecular Wittig reactions with the corresponding ester, thioester, and amide functionalities. The key intermediates, phosphorus ylides, presumably result from the addition of Bu3P toward aldehydes followed by acylation and deprotonation. Synthesis of functional benzofurans directly starting from salicylic aldehyde derivatives with acid chlorides in a one-step procedure is also developed. [ABSTRACT FROM AUTHOR]

Ketol-acid reductoisomerase (EC 1.1.1.86) is involved in the biosynthesis of the branched-chain amino acids. It is a bifunctional enzyme that catalyzes two quite different reactions at a common active site; an isomerization consisting of an alkyl migration, followed by an NADPH-dependent reduction of a 2-ketoacid. The 2-ketoacid formed by the alkyl migration is not released. Using the pure recombinantEscherichia colienzyme, we show that the isomerization reaction has a highly unfavourable equilibrium constant. The reductase activity is shown to be relatively nonspecific and is capable of utilizing a variety of 2-ketoacids. The active site of the enzyme contains eight conserved polar amino acids and we have mutated each of these in order to dissect their contributions to the isomerase and reductase activities. Several mutations result in loss of the isomerase activity with retention of reductase activity. However, none of the 17 mutants examined have the isomerase activity only. We suggest a reason for this, involving direct reduction of a transition state formed during the isomerization, which is necessitated by the unfavourable equilibrium position of the isomerization. Our mechanism explains why the two activities must occur in a single active site without release of a 2-ketoacid and provides a rationale for the requirement for NADPH by the isomerase. [ABSTRACT FROM AUTHOR]

Focuses on the catalysis of acetohydroxyacid synthase for the formation of branched amino acids. Combination of protein with the catalytic subunit of Arabidopsis thaliana; Reconstitution of catalytic subunit; Synergical effects of leucine and valine.

A highly chemoselective PPh3-catalyzed three-component reaction of an imine, alkyl vinyl ketone, and phthalimide or succinimide is developed. Various highly functional adducts with high diastereoselectivities can be generated via aza-Morita--Baylis--Hillman reactions of aryl-substituted imines and alkyl vinyl ketones followed by Michael additions of imides and then epimerization. [ABSTRACT FROM AUTHOR]

The increased prevalence of drug-resistant human pathogenic fungal diseases poses a major threat to global human health. Thus, new drugs are urgently required to combat these infections. Here, we demonstrate that acetohydroxyacid synthase (AHAS), the first enzyme in the branched-chain amino acid biosynthesis pathway, is a promising new target for antifungal drug discovery. First, we show that several AHAS inhibitors developed as commercial herbicides are powerful accumulative inhibitors of Candida albicans AHAS (Ki values as low as 800 pM) and have determined high-resolution crystal structures of this enzyme in complex with several of these herbicides. In addition, we have demonstrated that chlorimuron ethyl (CE), a member of the sulfonylurea herbicide family, has potent antifungal activity against five different Candida species and Cryptococcus neoformans (with minimum inhibitory concentration, 50% values as low as 7 nM). Furthermore, in these assays, we have shown CE and itraconazole (a P450 inhibitor) can act synergistically to further improve potency. Finally, we show in Candida albicans-infected mice that CE is highly effective in clearing pathogenic fungal burden in the lungs, liver, and spleen, thus reducing overall mortality rates. Therefore, in view of their low toxicity to human cells, AHAS inhibitors represent a new class of antifungal drug candidates. [ABSTRACT FROM AUTHOR]

A new highly efficient three-component reaction of alkyl acrylate, aldehyde and dialkyl malonate using ethyl diphenylphosphine as organocatalyst has been described. Various highly functional compounds bearing hydroxyl groups and the ester functions can be easily prepared in moderate to good yields according to our one-step procedure. The reactions are believed to proceed via Morita-Baylis-Hillman reactions of alkyl acrylate and aldehydes, followed by the Michael addition reactions of dialkyl malonates. Our reactions indicated that the intermediate species formed in the phosphine-catalyzed MBH reaction are an effective organic base to catalyze the Michael addition reactions of dialkyl malonates to the preformed MBH adducts. [ABSTRACT FROM AUTHOR]

Acetohydroxyacid synthase (AHAS; EC 2.2.1.6) catalyzes the first common step in branched-chain amino acid biosynthesis. The enzyme is inhibited by several chemical classes of compounds and this inhibition is the basis of action of the sulfonylurea and imidazolinone herbicides. The commercial sulfonylureas contain a pyrimidine or a triazine ring that is substituted at both meta positions, thus obeying the initial rules proposed by Levitt. Here we assess the activity of 69 monosubstituted sulfonylurea analogs and related compounds as inhibitors of pure recombinant Arabidopsis thaliana AHAS and show that disubstitution is not absolutely essential as exemplified by our novel herbicide, monosulfuron (2-nitro- N-(4′-methyl-pyrimidin−2′-yl) phenyl-sulfonylurea), which has a pyrimidine ring with a single meta substituent. A subset of these compounds was tested for herbicidal activity and it was shown that their effect in vivo correlates well with their potency in vitro as AHAS inhibitors. Three-dimensional quantitative structure–activity relationships were developed using comparative molecular field analysis and comparative molecular similarity indices analysis. For the latter, the best result was obtained when steric, electrostatic, hydrophobic and H-bond acceptor factors were taken into consideration. The resulting fields were mapped on to the published crystal structure of the yeast enzyme and it was shown that the steric and hydrophobic fields are in good agreement with sulfonylurea-AHAS interaction geometry. [ABSTRACT FROM AUTHOR]