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Acute liver injury is liver cell injury that occurs rapidly in a short period of time. Caffeine has been shown to maintain hepatoprotective effect with an unclear mechanism. Endoplasmic reticulum stress (ERS) has significant effects in acute liver injury. Induction of GRP78 is a hallmark of ERS. Whether or not caffeine's function is related to GRP78 remains to be explored.Acute liver injury model was established by LPS-treated L02 cells and in vivo administration of LPS/D-Gal in mice. Caffeine was pre-treated in L02 cells or mice. Gene levels was determined by real-time PCR and western blot. Cell viability was tested by CCK-8 assay and cell apoptosis was tested by flow cytometry. The interaction of GRP78 and NEDD4L was determined by Pull-down and co-immunoprecipitation (Co-IP) assay. The ubiquitination by NEDD4L on GRP78 was validated by in vitro ubiquitination assay.Caffeine protected liver cells against acute injury induced cell apoptosis and ERS both in vitro and in vivo. Suppression of GRP78 could block the LPS-induced cell apoptosis and ERS. NEDD4L was found to interact with GRP78 and ubiquitinate its lysine of 324 site directly. Caffeine treatment induced the expression of NEDD4L, resulting in the ubiquitination and inhibition of GRP78.Caffeine mitigated the acute liver injury by stimulating NEDD4L expression, which inhibited GRP78 expression via ubiquitination at its K324 site. Low dose of caffeine could be a promising therapeutic treatment for acute liver injury.

Chang-Shou She,1 Yue-Lin Deng,1 Guo-Qing Huang,1 Chao Cheng,2 Fang-Jie Zhang1,3 1Department of Emergency Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China; 2Department of Clinical Laboratory, Lixian People’s Hospital, Changde, Hunan, People’s Republic of China; 3National Clinical Research Center for Geriatric Disorders (Xiangya Hospital), Changsha, Hunan, People’s Republic of ChinaCorrespondence: Fang-Jie Zhang, Department of Emergency Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, People’s Republic of China, Tel +86 15116256248, Email zhangfj@csu.edu.cnPurpose: This study’s goal was to explore risk factors affecting short-term prognosis of cardiorenal syndrome type 1 (CRS1) in acute myocardial infarction (AMI) patients.Methods: In this retrospective analysis of CRS1 in AMI patients hospitalized from January 2011 to December 2014, the patients were classified into deceased or survivor groups. Clinical data, including demographics, laboratory results, and 28-day outcomes, were collected.Results: The incidence rate of CRS1 in AMI patients was 15.2% (274 in 1801). Ultimately, 88 patients were enrolled and 25 (28.4%) were classified into the deceased group, while 63 were classified into the survivor group. There were statistically significant differences between the groups for hypertension, mechanical ventilation, KIDGO stage, NT-proBNP, Hb, ALB, PCI, decreased LVEF, 7th-day SCr value, and the highest SCr value recorded within 7 days (all P < 0.05). Multivariate logistic regression showed that the following factors were significantly related to whether a patient died: requiring mechanical ventilation, increased NT-proBNP levels and 7th-day SCr values, and decreased LVEFs. The APACHE II, SOFA, and SASP II scores on the 7th day were significantly higher in the deceased group (all P < 0.05). The accuracy of APACHE II, SOFA, and SASP II scores on the 7th day for predicting death were 84.1%, 78.4% and 79.5%, respectively. The AUC of 7th-day APACHE II, SOFA, and SASP II scores was 0.844, 0.803, and 0.827, respectively, with no statistically significant differences between the three scores (P > 0.05).Conclusion: The mortality rate of CRS1 in AMI patients was 28.4% (25 in 88) within 28 days. Mechanical ventilation, increased NT-proBNP levels, the 7th-day SCr value, and decreased LVEF were related to death in AMI patients with CRS1. APACHE II, SOFA, and SAPS II scores on the 7th day were satisfactorily accurate in predicting death within 28 days.Keywords: acute myocardial infarction, cardiorenal syndrome type 1, APACHE II, SOFA, SAPS II, mortality

Osteoarthritis (OA) is the main joint disease associated with aging. Previous studies have confirmed that both osteopontin (OPN) and αvβ3 integrin are involved in the progression of knee OA. The purpose of this study was to determine the expression of OPN and αvβ3 integrin and chondrocyte senescence levels in OA. Forty-six cartilage tissues from normal and knee OA patients were divided into 4 groups of normal, minor, moderate, and severe lesions based on the Mankin score. Immunohistochemistry and western blotting were used to determine the expression of αvβ3, OPN, and senescent-associated-β-galactosidase (SAβ-gal) in articular cartilage. Then, Spearman's correlation was used to analyze the correlations between the Mankin scores and αvβ3, OPN and SAβ-gal. Pearson correlation analysis was used to analyze the correlations among αvβ3, OPN, and SAβ-gal. The expression of OPN, αvβ3, and SAβ-gal in articular cartilage was explored. αvβ3, OPN, and SAβ-gal proteins were all elevated in OA cartilage, and the correlation coefficient between the Mankin score and the average optical density value of αvβ3, OPN, SAβ-gal were r =0.60, r =0.75, and r =0.87, respectively, all P0.001; the correlation between the average optical density value of αvβ3 and OPN was r =0.3191, P0.05; the correlation between αvβ3 and SAβ-gal was r =0.4955, P0.001; and the correlation between OPN and SAβ-gal was r =0.7821, P0.001. The correlations among αvβ3, OPN, and SAβ-gal expression in articular cartilage might be important in OA progression and pathogenesis. Nonetheless, more research is needed to elucidate the exact contribution of αvβ3, OPN, and SAβ-gal to the degenerative process of OA.

The aim of the present study was to investigate the effect of ulinastatin (UTI) alone or combined with mild therapeutic hypothermia (MTH) on intestinal barrier dysfunction following cardiopulmonary resuscitation (CPR) in rats. A total of 25 adult male Sprague-Dawley rats were randomly organized into five groups: Sham; control; UTI; MTH; and the combined group. The latter four groups were induced with the asphyxiated cardiac arrest rat model and treated with different interventions. After 6 h of treatment, the intestinal tissues of the rats were examined by electron microscopy, and the levels of intestinal malondialdehyde (MDA) and superoxide dismutase (SOD) were determined. The results of the present study indicated that the target temperature had successfully been attained in MTH and the combined group, and the other three groups of rats all survived at a normal temperature. In the rats treated with UTI or MTH, the epithelial cells exhibited pathological changes in their tight junctions and epithelial cell surface microvilli compared with the sham group. In the rats treated with a combination of UTI and MTH, whilst the epithelial cells exhibited a few slight changes, including mitochondrial edema, they were largely similar to the normal epithelial cells. However, there were significant differences in the levels of MDA and SOD between the different treatment groups. UTI combined with MTH may serve a protective role by suppressing oxidative stress in the small intestinal mucosa following CPR in rats compared with either UTI or MTH treatment alone.

Objectives: Our goal in this study was to determine 1) whether there are any differences in clinical characteristics between Chinese and Western patients with aortic dissection (AD), and 2) the mortality rate of AD patients in the emergency department (ED) and identify the risk predictors for death. Methods: We retrospectively analyzed patients who were diagnosed with AD and admitted to our ED between September 1, 2017–August 31, 2020. Data on age, gender, clinical manifestation, medical history, routine blood tests, liver and kidney function, coagulation, myocardial enzymology, and mortality were collected. Results: We enrolled 535 AD patients (422 men and 113 women) with a mean age of 54.7±14.1 years. Type A AD constituted 40% of the total number of AD cases, while type B AD constituted 60%. The proportion of those who were females, 10-92 years, with type A AD, and hypertension in the Chinese population was lower than that in the Western population (P

The aim of the present study was to investigate the in vitro effect of osteopontin (OPN) on the expression of hypoxia-inducible factor-2α (HIF-2α) in chondrocytes and the role of OPN in osteoarthritis (OA). Cartilage was purified from the tibial surfaces of patients with OA of the knee and cultured in vitro to obtain chondrocytes. Recombinant human OPN (rhOPN) and OPN small interfering RNA (siRNA) were used to treat the chondrocytes, and the changes in the expression levels of the HIF-2α gene were measured. An anti-CD44 blocking monoclonal antibody (mAb) was used to determine the probable ligand-receptor interactions. Reverse transcription-quantitative polymerase chain reaction assays were designed and validated with SYBR® Green dyes for the simultaneous quantification of the mRNA expression levels of OPN and HIF-2α. The mRNA expression level of HIF-2α was markedly decreased in the rhOPN-treated group compared with that in the control group; by contrast, OPN siRNA increased HIF-2α gene expression. CD44 blocking mAb suppressed the inhibitory effect of OPN on HIF-2α mRNA expression. The results of the present study suggest that OPN may play a protective role in OA by inhibiting HIF-2α gene expression in osteoarthritic chondrocytes through CD44 interaction.

Previous studies have demonstrated that osteopontin (OPN) levels are elevated in the synovial fluid and articular cartilage, and are associated with the severity of knee osteoarthritis (OA). However, the role of OPN in the pathogenesis of OA has yet to be elucidated. The present study aimed to investigate the effects of OPN on the expression of the aggrecanases, a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)4 and ADAMTS5, in human OA chondrocytes, as they serve a key function in aggrecan degradation. Human OA chondrocytes were obtained from the knees of 16 patients with OA, and subsequently cultured in a monolayer. The chondrocytes were divided into three groups, which included the control (no treatment), N-OPN (treated with 100 ng/ml OPN, the normal circulating OPN concentration) and the H-OPN groups (treated with 1 µg/ml OPN, a high OPN concentration). Reverse transcription-quantitative polymerase chain reaction was performed to quantify the relative mRNA expression levels of ADAMTS4, ADAMTS5 and aggrecan in the chondrocytes. The mRNA expression levels of ADAMTS4 were significantly reduced in the N-OPN and H-OPN groups when compared with the control group (P0.05). Furthermore, the mRNA expression levels of aggrecan were higher in the N-OPN and H-OPN groups when compared with the control group (P

Chemerin is a novel adipokine, which is linked to adipogenesis and chemotaxis of the innate immune system. This study aimed to evaluate the relationship between preoperative plasma chemerin level and prognosis of gastric cancers. One hundred ninety-six patients and 196 age- and gender-matched healthy individuals were recruited. Fasting venous blood samples were collected 2 days prior to surgery for the gastric cancer patients and at the physical examination day for the healthy volunteers. Recorded clinicopathological information included invasion depth, lymph node metastasis, distant metastasis, peritoneal dissemination, tumor size and tumor-node metastasis stage. Plasma chemerin levels were determined using enzyme-linked immunosorbent assay. Plasma chemerin levels were statistically significantly in all patients than in healthy controls (53.1 ± 19.0 ng/mL vs. 31.3 ± 11.3 ng/mL; P0.001). And it was identified as an independent predictor for 5-year mortality [odds ratio (OR), 2.718; 95% confidence interval (CI), 1.201-4.229; P = 0.005) and adverse event (OR, 2.982; 95% CI, 1.223-4.879; P = 0.003) of gastric cancer, and had high area under receiver operating characteristic curve (AUC) for prediction of 5-year mortality (AUC, 0.808; 95% CI, 0.745-0.860) and adverse event (AUC, 0.787; 95% CI, 0.723-0.842). It also emerged as an independent predictor for overall survival (Hazard ratios, 1.788; 95% CI, 1.200-2.663; P = 0.002) and disease-free survival (Hazard ratios, 2.016; 95% CI, 1.312-3.125; P = 0.004). Thus, our results suggest that high plasma chemerin levels are associated with long-term poor prognosis and survival of gastric cancer as well as may play a role as prognostic biomarker in gastric cancer survival.

Programmed cell death 2 (PDCD2) is a highly conserved nuclear protein, and aberrant PDCD2 expression alters cell apoptosis. The present study aimed to investigate PDCD2 expression in gastric cancer. Tissue specimens from 34 gastric cancer patients were collected for analysis of PDCD2 expression using immunohistochemistry, western blotting and qRT-PCR. Gastric cancer cell lines (a p53-mutated MKN28 line and a wild-type p53 MKN45 line) were used to assess the effects of PDCD2 overexpression. p53-/- nude mice were used to investigate the effect of PDCD2 on ultraviolet B (UVB)-induced skin carcinogenesis. The data showed that PDCD2 expression was reduced in gastric cancer tissue specimens, and loss of PDCD2 expression was associated with the poor survival of patients. PDCD2 expression induced gastric cancer cell growth arrest at the early S phase of the cell cycle and apoptosis. The antitumor effects of PDCD2 expression were dependent on p53 expression in gastric cancer cells. Moreover, PDCD2 expression inhibited activity of the ATM/Chk1/2/p53 signaling pathway. In addition, PDCD2 expression suppressed UVB-induced skin carcinogenesis in p53+/+ nude mice, but not in p53-/- mice. The data from the present study demonstrated that loss of PDCD2 expression could contribute to gastric cancer development and progression and that PDCD2-induced gastric cancer cell growth arrest at the early S phase of the cell cycle and apoptosis are p53-dependent.

Tissue inhibitors of metalloproteinases (TIMPs) regulate the activity of matrix metalloproteinases (MMPs) and enzymes from the a disintegrin and metalloproteinase domain with thrombospondin motifs family in osteoarthritis (OA). Elevated osteopontin (OPN) levels in plasma, synovial fluid and articular cartilage are associated with progressive OA joint damage; however, the role of OPN in the pathological changes of knee OA remains undetermined. The present study was undertaken to examine the effect of OPN on the expression of TIMP-1 and TIMP-2 mRNA in chondrocytes from 16 patients with knee OA. In this study, following the stimulation of human chondrocytes with recombinant human OPN (rhOPN; 100 ng/ml and 1 μg/ml, respectively) for 48 h, MTT assay was used to determine cell viability while the quantitative polymerase chain reaction (PCR) was used to detect the alterations in TIMP-1 and TIMP-2 levels. The results illustrated that neither 100 ng/ml nor 1 μg/ml rhOPN caused cytotoxicity or apoptosis of chondrocytes and that the relative mRNA expression of TIMP-1 and TIMP-2 was significantly increased in the 1 μg/ml rhOPN group compared with that in the control group (P=0.022 and P=0.003, respectively). However, no significant difference in expression was revealed between the 100 ng/ml rhOPN and control groups (P=0.998 and P=0.209, respectively). In conclusion, OPN may have a protective effect against pathological changes in advanced-stage OA.

Reactive metabolites have been putatively linked to many adverse drug reactions including idiosyncratic toxicities for a number of drugs with black box warnings or withdrawn from the market. Therefore, it is desirable to minimize the risk of reactive metabolite formation for lead molecules in optimization, in particular for non-life threatening chronic disease, to maximize benefit to risk ratio. This article describes our effort in addressing reactive metabolite issues for a series of 3-amino-2-pyridone inhibitors of BTK, e.g. compound 1 has a value of 459 pmol/mg protein in the microsomal covalent binding assay. Parallel approaches were taken to successfully resolve the issues: establishment of a predictive screening assay with correlation association of covalent binding assay, identification of the origin of reactive metabolite formation using MS/MS analysis of HLM as well as isolation and characterization of GSH adducts. This ultimately led to the discovery of compound 7 (RN941) with significantly reduced covalent binding of 26 pmol/mg protein.

A new approach to the synthesis of 2,2″-biflavanones by the reductive dimerization of flavones is reported. The products, the racemate and meso biflavanones, have been separated and their structures have been determined on the basis of their spectral data. The configuration of 3b has been determined by X-ray crystallography as well.

The reaction of 2′-hydroxychalcones with I2-H2SO4-DMSO system has been studied. The results obtained by us are entirely different from those reported in the literature. The mechanism of this reaction has also been investigated.

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are part of the preferred treatment regimens for individuals infected with HIV. These NNRTI-based regimens are efficacious, but the most popular NNRTIs have a low genetic barrier to resistance and have been associated with adverse events. There is therefore still a need for efficacious antiviral medicines that facilitate patient adherence and allow durable suppression of viral replication. As part of an extensive program targeted toward the discovery of NNRTIs that have favorable pharmacokinetic properties, good potency against NNRTI-resistant viruses, and a high genetic barrier to drug resistance, we focused on the optimization of a series of diaryl ether NNRTIs. In the course of this effort, we employed molecular modeling to design a new set of NNRTIs that that are active against wild-type HIV and key NNRTI-resistant mutant viruses. The structure-activity relationships observed in this series of compounds provide insight into the structural features required for NNRTIs that inhibit the replication of a wide range of mutant viruses. Selected compounds have promising pharmacokinetic profiles.

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are recommended components of preferred combination antiretroviral therapies used for the treatment of HIV. These regimens are extremely effective in suppressing virus replication. Structure-based optimization of diaryl ether inhibitors led to the discovery of a new series of pyrazolo[3,4-c]pyridazine NNRTIs that bind the reverse transcriptase enzyme of human immunodeficiency virus-1 (HIV-RT) in an expanded volume relative to most other inhibitors in this class.The binding mode maintains the beta13 and beta14 strands bearing Pro236 in a position similar to that in the unliganded reverse transcriptase structure, and the distribution of interactions creates the opportunity for substantial resilience to single point mutations. Several pyrazolopyridazine NNRTIs were found to be highly effective against wild-type and NNRTI-resistant viral strains in cell culture.

Gastric cancer was the third cause of death in China. In this study, we found that the APOBEC3 (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3) expression was higher in gastric cancer tissues than that in normal tissues and confirmed APOBEC3B expression was correlated with the unfavorable prognosis of the patients with gastric cancer. Furthermore, APOBEC3B expression was associated with gender, tumor size, histological grade, T stage, and TNM staging of the patients with gastric cancer. Down-regulation of APOBEC3B expression in MNK28 cells could enhance the cytotoxicity of PDCD2. No editing took place in PDCD2 positive MKN28 cells with APOBEC3B shRNA. These results indicated that loss of function of PDCD2 may be partly caused by APOBEC3B-induced extensive mutagenesis.

Syntheses of sterically crowded derivatives of benzo[ s ]picene and naphtho[1,2,3,4- rst ]pentaphene and their bis -dihydrodiol metabolites via a method that involves in the key steps double Suzuki coupling of aryl bis -boronic acid and o -bromoaryl aldehyde precursors are described.

Wnt inhibitory factor (WIF)-1 is a potent extracellular Wnt antagonist which may be used as a potential molecular therapy for the treatment of inflammatory and autoimmune diseases. Although previous studies have demonstrated that WIF-1 has a protective role in experimental studies of arthritis, its role in the various disease grades of osteoarthritis (OA) remains unclear. A total of 40 patients with various stages of primary OA of the knee and 10 control subjects were enrolled in the present study. Articular cartilage specimens were harvested from subjects following total knee arthroplasty or knee above amputation. Disease severity was determined according to Modified Mankin score and cartilage tissues were ascribed to four groups: Normal, mild, moderate and severe lesions. WIF-1 expression levels in articular cartilage were measured using immunohistochemical techniques. WIF-1 expression levels were detected in all cartilage tissues. As compared with the controls, patients with OA exhibited significantly decreased WIF-1 expression levels in the articular cartilage (0.19±0.05 vs. 0.26±0.04; P

The tri-peptide [14C]-glutathione ([14C]-GSH) was synthesized in a single step by GSH synthetase catalyzed reaction of L-γ-glutamyl-L-cysteine and [14C]-glycine. Preparative reverse phase HPLC afforded [14C]-GSH in 30% yield and 98% purity. Preparation of GSH synthetase from E. coli via recombinant DNA and the interconversion of [14C]-GSH to the disulfide [14C]-GSSG for storage are discussed. Copyright © 2010 John Wiley & Sons, Ltd.

The synthesis, structures, and mutagenic properties of benzo[a]pyrene-deoxyadenosine adducts in a sequence context related to the p53 gene are described.

Coal tar is a complex mixture that exhibits high carcinogenic potency in lungs of animals when administered in the diet. Studies have noted that lung tumor induction does not correlate with the benzo[a]pyrene content of coal tar, suggesting that other hydrocarbons may be involved in the observed tumorigenicity. Our previous studies have demonstrated that a major 'unknown' chemical-DNA adduct is formed in the lung of mice exposed to coal tar. We have used an in vitro rat microsomal activation system to generate the 'unknown' adduct with neat coal tar and fractions of coal tar obtained by chemical fractionation and HPLC. Chemical-DNA adduct formation was evaluated by (32)P-postlabeling using both multi-dimensional TLC and HPLC. GC-MS analysis of the coal tar fractions obtained from HPLC, which produced the 'unknown' adduct in vitro, demonstrated that the adducting hydrocarbon had a mass of 216. A careful evaluation of candidate hydrocarbons led to the conclusion that a benzofluorene derivative may be responsible for forming the 'unknown' chemical-DNA adduct. Comparative in vitro and in vivo studies on the adducting properties of all three isomers of benzofluorene indicated that 7H-benzo[c]fluorene is responsible for producing the 'unknown' adduct observed in the lung of mice ingesting coal tar. Animal feeding studies also demonstrated that 7H-benzo[c]fluorene formed considerably more lung DNA adducts than 11H-benzo[a]fluorene and 11H-benzo[b]fluorene. These data indicate that the four-ring polycyclic aromatic hydrocarbon 7H-benzo[c]fluorene, a hydrocarbon not previously shown to form DNA adducts in lung, is in fact a potent lung DNA adductor and is a candidate PAH for causing lung tumors in animals treated with coal tar.

Evidence concerning the role of dihydrodiol dehydrogenase-catalyzed formation of quinone metabolites in the mechanism in PAH carcinogenesis is reviewed and methods for the synthesis of the adducts formed by reaction of PAH quinone metabolites with DNA are reported.

Mutations in the human p53 tumor suppressor gene are prominently linked to sporadic cancers in breast, lung and other tissues. Recent research has shown that tobacco-associated cancer in the human lung is related to mutation of the p53 gene mediated by the carcinogen benzo[a]pyrene (BaP), and the mutations are targeted to DNA "hot spots" at specific codons. In order to gain insight into the relation between the structures of the adducts formed by BaP at these sites and their mutagenic activities, we have synthesized site-specifically modified oligo-nucleotide adducts of the active BaP diol epoxide metabolite (anti-BaPDE). This manuscript reports on the mutagenic consequences of replication past anti-BaPDE-deoxyadenosine adducts located within a sequence context related to codon 157 in exon 5 of the p53 gene. In this sequence context, the adduct derived from the carcinogenic 7R,8S-dihydrodiol 9S,10R-epoxide was much more active as a mutagen than the adduct derived from the noncarcinogenic 7S,8R-dihydrodiol 9R,10S-epoxide and the mutation found most frequently was an A-->G transition. Since previous studies in other sequence contexts have yielded somewhat different findings, these studies further emphasize the key role played by sequence context in determining the mutational properties of carcinogen-DNA adducts.

Anti benzo[s]picene 9,10-dihydrodiol 11,12-epoxide was reacted with calf thymus DNA and with its constituent deoxyribonucleotides. The origin of DNA adducts was established by comparison of their HPLC retention times and UV spectra with those of the nucleotide-derived adduct-markers. The low binding of the dihydrodiol epoxide to DNA (2%) and to deoxyguanylic and deoxyadenylic acids precluded an NMR study, and assignment of cis or trans epoxide ring opening was made by analogy to other anti dihydrodiol epoxide adducts. The adduct ratio for dGuo/dAdo in DNA was 24/76 and the ratios of dGuo cis/dGuo trans and dAdo cis/dAdo trans were 40/60 and 6/94, respectively.

The objective of this brief review is to present an overview of the bioorganic chemistry of cyclic-ADP-ribose (cADPR) with special emphasis on the methodology used for the synthesis of analogues of cADPR. New structural analogues of cADPR can be prepared using either the biomimetic method or ADP-ribosyl cyclase from Aplysia californica. For the most part, both procedures give similar product profiles, but higher yields are generally obtained with the enzymatic method. These synthetic methodologies have allowed the transformation of a variety of structurally modified analogues of NAD+ into their corresponding cyclic nucleotides. Several of these novel analogues are more potent than cADPR in inducing calcium release and are also more stable towards degradative enzymes. They could serve as valuable affinity probes for the isolation of cADPR-binding proteins.

Efficient syntheses of the trans-3,4-trans-9,10-tetrahydroxy-3,4,9,10-tetrahydro derivatives of benzo[s]picene and the corresponding bis-anti-diol epoxide derivatives in which the epoxide rings lie in the sterically crowded fjord regions are reported. Bis-dihydrodiols and bis-anti-diol epoxides of this type are suspected as proximate and ultimate carcinogenic metabolites, respectively, of several polycyclic aromatic hydrocarbons. These are the first examples of this class of molecules to be synthesized. The syntheses entail in the key step double oxidative photocyclization of a tetramethoxy-2,3-distyrylnaphthalene obtained from double Wittig reaction of naphthalene-2,3-dialdehyde. The bis-dihydrodiols were obtained as a mixture of meso and racemic diastereomers separable by HPLC on a reversed-phase ZORBAX ODS column. The bis-anti-diol epoxide enantiomers derived from the latter were resolved by HPLC on a chiral column.

8-(6-Aminohexyl) amino-cyclic ATPR, a new affinity probe for the study of cADPR-binding proteins, was prepared in four steps with an overall yield of 21%.

Detailed oxidation/reduction pathways that lead to the formation of 2,4,5-trihydroxyphenolic compounds during the oxidation of dopa, hydrocaffeic acid and N-acetyldopa are described. Data suggest that (i) oxidation of dopa, hydrocaffeic acid and N-acetyldopa results in the formation of their corresponding o-quinones, (ii) the o-quinones undergo intramolecular nucleophilic addition through the side chain carboxy group to form lactones under weak acid conditions, (iii) oxidation of the lactones produces their corresponding lactone-o-quinones, (iv) the lactone-o-quinones, once formed, undergo rapid hydrolysis that leads to the formation of 2-hydroxy-1,4-benzoquinones (p-quinones) as relatively stable products and (v) reduction of the p-quinones results in the formation of their corresponding 6-hydroxydopa, 6-hydroxyhydrocaffeic acid and N-acetyl-6-hydroxydopa. Data suggest that 6-hydroxydopa also can be produced by direct hydrolysis of dopa-lactone.

Cyclic ATP-ribose, synthesized by a combination of chemical and enzymatic methods, was twenty times more potent than cADPR in inducing Ca 2+ release from rat brain microsomes. It induced Ca 2+ release from the same Ca 2+ stores as that of cADPR, but different from those of IP 3 and cyclic ADP-ribose-phosphate.

Summary The cyclase of Aplysia californica catalyzed an alternative mode of cyclization of nicotinamide guanine dinucleotide (NGD) and nicotinamide hypoxanthine dinucleotide (NHD) to form cyclic-GDP-ribose (cGDPR) and cyclic-HDP-ribose (cHDPR) respectively. In these cyclic nucleotides, the newly formed glycosyl bonds are attached onto the N-7 nitrogen of the purine rings instead of the N-1 nitrogen as in cyclic ADP-ribose (cADPR).

The ADP-ribosyl cyclase of Aplysia californica catalyzed the conversion of NADP, 3′-NADP and 2′,3′-cyclic NADP into their corresponding cyclic nucleotides (established by NMR, UV, and MS analyses). Cyclic-ADP-ribose-phosphate (cADPRP) was more potent than cADPR in mobilizing calcium in the rat brain microsomal system; the EC50 for cADPRP and cADPR were 9.2 μM and 22 μM respectively.

The ADP-ribosyl cyclase from Aplysia californica catalyzed the transformation of 1,N 6 -etheno-nicotinamide-adenine dinucleotide ( 2 ) into a novel cyclic nucleotide, 3 . The newly formed glycosyl linkage is attached onto the N-1 position of the etheno-adenine ring corresponding to the N-7 position of the adenine nucleus. This alternative mode of cyclization gives more versatility in the biosynthesis of novel analogs of cADPR ( 1 ).

Reactions of the 3—iodo derivatives of flavones, thioflavones and thiochromones with finely divided copper at 200–210°C gave the title compounds respectively. Thus a new way to these compounds was provided.

The title compounds, 2-aryl-3-iodo-4H-1-benzopyrans and 2-alkyl- or 2-aryl-3-iodo-4H-1-benzothiopyrans, were prepared by reaction of the corresponding heterocyclic derivatives with the iodine-cerium(IV) ammonium nitrate system under mild conditions. The scope and proposed mechanism of the reaction were also demonstrated

8-(6-Aminohexyl) amino-cyclic ATPR, a new affinity probe for the study of cADPR-binding proteins, was prepared in four steps with an overall yield of 21%.

Efficient syntheses of the trans-3,4-trans-9,10-tetrahydroxy-3,4,9,10-tetrahydro derivatives of benzo[s]picene and the corresponding bis-anti-diol epoxide derivatives in which the epoxide rings lie in the sterically crowded fjord regions are reported. Bis-dihydrodiols and bis-anti-diol epoxides of this type are suspected as proximate and ultimate carcinogenic metabolites, respectively, of several polycyclic aromatic hydrocarbons. These are the first examples of this class of molecules to be synthesized. The syntheses entail in the key step double oxidative photocyclization of a tetramethoxy-2,3-distyrylnaphthalene obtained from double Wittig reaction of naphthalene-2,3-dialdehyde. The bis-dihydrodiols were obtained as a mixture of meso and racemic diastereomers separable by HPLC on a reversed-phase ZORBAX ODS column. The bis-anti-diol epoxide enantiomers derived from the latter were resolved by HPLC on a chiral column.

The objective of this brief review is to present an overview of the bioorganic chemistry of cyclic-ADP-ribose (cADPR) with special emphasis on the methodology used for the synthesis of analogues of cADPR. New structural analogues of cADPR can be prepared using either the biomimetic method or ADP-ribosyl cyclase from Aplysia californica. For the most part, both procedures give similar product profiles, but higher yields are generally obtained with the enzymatic method. These synthetic methodologies have allowed the transformation of a variety of structurally modified analogues of NAD+ into their corresponding cyclic nucleotides. Several of these novel analogues are more potent than cADPR in inducing calcium release and are also more stable towards degradative enzymes. They could serve as valuable affinity probes for the isolation of cADPR-binding proteins.

To investigate the expression and significance of HIF1 alpha in hepatocellular carcinoma (HCC) tissues and in hepatoma carcinoma cell line HepG2.The expression of the HIF1 alpha mRNA and protein were detected with immunohistochemistry (IHC), Western blot and RT-PCR techniques in HCC, normal liver tissues and HepG2. Their relationship with the pathological characteristics of the HCC was also analyzed.HIF1 alpha protein was obviously expressed in HCC. The positive rate of HIF1 alpha protein in HCC tissues was 76.4% and was higher than that in normal hepatic tissues. The expression of HIF1 alpha had a correlation to the differentiation degree of HCC tissues and intrahepatic and extrahepatic metastases (P0.05), but there was no correlation to the existence of portal vein tumor emboli, the status of HBsAg and the prognosis (P0.05). The results of Western blot and RT-PCR were similar to the results of IHC. The positive rate of HIF1 alpha in HepG2 was 93.6%. The levels of HIF1 alpha protein and mRNA began to increase after being treated two hours with hypoxia or with CoCl(2) (150 micromol/L).HIF1 alpha protein is obviously expressed in HCC and it is mainly affected by hypoxia. The expression of HIF1 alpha is related to the differentiation of the HCC and its intrahepatic and extrahepatic metastases but has no correlation to the existence of portal vein tumor emboli, the status of HBsAg and the prognosis.

The title compounds, 2-aryl-3-iodo-4H-1-benzopyrans and 2-alkyl- or 2-aryl-3-iodo-4H-1-benzothiopyrans, were prepared by reaction of the corresponding heterocyclic derivatives with the iodine-cerium(IV) ammonium nitrate system under mild conditions. The scope and proposed mechanism of the reaction were also demonstrated