2-Cyanoethylzinc iodide: A new reagent with reactivity umpolung

2-Cyanoethylzinc iodide 1 generated in over 90% yield from 3-iodopropionitrile and zinc in THF can be transmetallated to the copper and titanium derivatives 3 and 4 which react in good yields, respectively, with acyl chlorides, enones, allylic halides and benzaldehyde.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27612/1/0000656.pd

A Mild Oxidation of 1.1 - Diorganometallics to Ketones and Aldehydes. A New Stereoselective Aunroach to Aldol products - Part 1

The 1,1-diorganometallics of magnesium and zinc 1 are converted by the reaction with Me3SnCl to the 1,1-diorganometallics of tin and zinc 2 which are readily oxidized by dry air at -10[deg] to 0[deg]C to afford the corresponding aldehydes and ketones 3 in 57-91% yield. This mild oxidation reaction allows a new stereoselective approach to aldol products. An extension of the reaction to 1,1-diorganometallics of silicon and zinc is described.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27621/1/0000665.pd

The reaction of the highly functionalized copper reagents RCu(CN)ZnI.BF3 with aldehydes

The new copper reagent RCu(CN)ZnI 2, which may contain important functional groups like the ester, nitrile, enoate or imide group, react in the presence of BF3.OEt2 with aldehydes to afford polyfunctional secondary alcohols in good yields (68-93%).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27616/1/0000660.pd

Synthesis and characterization of new fluorescent two-photon absorption chromophores{

A series of dipolar and quadrupolar type two-photon absorption (TPA) compounds has been synthesized and TPA cross sections (s) were measured by Ti:sapphire femtosecond laser excitation fluorescence (l = 800 nm). Among them, the compound ) can be achieved. One quadrupolar molecule (13) possessing an arylamine donor and a pyridazine acceptor has both a high s value (1442 GM) and s/MW (1.97 GM/g)

Management of Hepatic Angiomyolipoma

Preoperative diagnosis of hepatic angiomyolipoma is difficult, and the treatment for it remains controversial. The aim of this study is to review our experience in the treatment of hepatic angiomyolipoma and to propose a treatment strategy for this disease. We retrospectively collected the clinical, imaging, and pathological features of patients with hepatic angiomyolipoma. Immunohistochemical studies with antibodies for HMB-45, actin, S-100, cytokeratin, vimentin, and c-kit were performed. Treatment experience and long-term follow-up results are summarized. During a period of 9 years, 10 patients with hepatic angiomyolipoma were treated at our hospital. There was marked female predominance (nine patients). Nine patients received surgical resection without complications. One patient received nonoperative management with biopsy and follow-up. One patient died 11 months after surgery because of recurrent disease. We propose all symptomatic patients should receive surgical resection for hepatic angiomyolipoma. Conservative management with close follow-up is suggested in patients with asymptomatic tumors and meet the following criteria: (1) tumor size smaller than 5 cm, (2) angiomyolipoma proved through fine needle aspiration biopsy, (3) patients with good compliance, and (4) not a hepatitis virus carrier

Emergence of the rtA181T/sW172* mutant increased the risk of hepatoma occurrence in patients with lamivudine-resistant chronic hepatitis B

<p>Abstract</p> <p>Background</p> <p>Development of the hepatitis B virus (HBV) rtA181T/sW172* mutant could occur during prolonged lamivudine (LAM) therapy, conferring cross resistance to adefovir. Recent studies demonstrated an increased oncogenic potential of this mutant in NIH3T3 cells. In this study, we aimed to investigate the clinical significance of this finding.</p> <p>Methods</p> <p>Serum samples from 123 LAM-resistant chronic hepatitis B patients were submitted for virological assays. A highly sensitive amplification created restriction enzyme site (ACRES) method was devised to detect small amounts of the rtA181T mutant in the serum. Virological factors including HBV-DNA level, genotype, precore G1896A, BCP A1762T/G1764A, rtM204I/V, rtA181T and pre-S internal deletion mutations as well as clinical variables including subsequent use of rescue drugs were submitted for outcome analysis.</p> <p>Results</p> <p>By use of the highly sensitive ACRES method, the rtA181T mutant was detectable in 10 of the 123 LAM-resistant patients. During the mean follow-up period of 26.2 ± 16.4 months (range 2 to 108 months), 3 of the 10 (30.0%) rtA181T-positive patients and 2 of the 113 (1.8%) rtA181T-negative patients developed hepatocellular carcinoma (HCC). Kaplan-Meier analysis indicated that the presence of rtA181T mutation (P < 0.001), age > 50 years (P = 0.001), and liver cirrhosis (P < 0.001) were significantly associated with subsequent occurrence of HCC. All 5 HCC patients belonged to the older age and cirrhosis groups.</p> <p>Conclusions</p> <p>Emergence of the rtA181T/sW172* mutant in LAM-resistant patients increased the risk of HCC development in the subsequent courses of antiviral therapy.</p

Antimetastatic Effects of Norcantharidin on Hepatocellular Carcinoma by Transcriptional Inhibition of MMP-9 through Modulation of NF-kB Activity

The rate of morbidity and mortality of hepatocellular carcinoma (HCC) in Taiwan has not lessened because of difficulty in treating tumor metastasis. Norcantharidin (NCTD) is currently used as an anticancer drug for hepatoma, breast cancer, and colorectal adenocarcinoma. NCTD possesses various biological anticancer activities, including apoptosis. However, detailed effects and molecular mechanisms of NCTD on metastasis are unclear. Thus, HCC cells were subjected to treatment with NCTD and then analyzed to determine the effects of NCTD on cell metastasis.Modified Boyden chamber assays revealed that NCTD treatment inhibited cell migration and invasion capacities of HCC cells substantially. Results of zymography and western blotting showed that activities and protein levels of matrix metalloproteinase-9 (MMP-9) and urokinase plasminogen activator (u-PA) were inhibited by NCTD. Western blot analysis showed that NCTD inhibits phosphorylation of ERK1/2. Testing of mRNA level, quantitative real-time PCR, and promoter assays evaluated the inhibitory effects of NCTD on MMP-9 and u-PA expression in HCC cells. The chromatin immunoprecipitation (ChIP) assay for analyzing the genomic DNA sequences bound to these proteins was reactive to the transcription protein nuclear factor (NF)-kappaB, which was inhibited by NCTD. The expression of NF-kappa B was measured by western blot analysis, which revealed decreased nuclear-factor DNA-binding activity after NCTD treatment.NCTD inhibited MMP-9 and u-PA expression through the phosphorylation of ERK1/2 and NF-kappaB signaling pathway which serves as a powerful chemopreventive agent in HCC cell metastasis

Paraoxonase-1 Is Not a Major Determinant of Stent Thrombosis in a Taiwanese Population

BACKGROUND: Clopidogrel is a prodrug that undergoes in vivo bioactivation to show its antiplatelet effects. Recent studies have shown that cytochrome P450 (CYP), ATP-binding cassette transporters (ABCB1), and paraoxonase-1 (PON1) play crucial roles in clopidogrel bioactivation. Here, we aim to determine the effects of genetic polymorphisms of CYP (CYP 2C19*2, CYP 2C19*3, and CYP 2C19*17), ABCB1 (ABCB1 3435C>T, ABCB1 129T>C, and ABCB1 2677G>T/A), and PON1 (PON1 Q192R, PON1 L55M, and PON1 108C>T) on the development of stent thrombosis (ST) in patients receiving clopidogrel after percutaneous coronary intervention (PCI). METHODS AND RESULTS: We evaluated the incidence of ST (0.64%) in 4964 patients who were recruited in the CAPTAIN registry (Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions). The presence of genetic polymorphisms was assessed in 20 subjects who developed ST after aspirin and clopidogrel therapy and in 40 age- and sex-matched control subjects who did not develop ST, which was documented after 9 months of angiographic follow-up. ST was acute in 5 subjects, subacute in 7, late in 7, and very late in 1. The presence of CYP 2C19*2 allele was significantly associated with ST (adjusted odds ratio [ORadj]: 4.20, 95% confidence interval [CI], 1.263-9.544; P = 0.031). However, genetic variations in PON1 and ABCB1 showed no significant association with ST. CONCLUSION: We conclude that in a Taiwanese population, PON1 Q192R genotype is not associated with ST development after PCI. However, the presence of CYP 2C19*2 allele is a risk factor for ST development after PCI

Diagnosis and treatment delay among pulmonary tuberculosis patients identified using the Taiwan reporting enquiry system, 2002–2006

<p>Abstract</p> <p>Background</p> <p>The tuberculosis reporting enquiry system was launched in Taiwan in 2001. Tuberculosis has been categorized as the third most important notifiable disease in Taiwan and the time required for reporting has been shortened to 7 days.</p> <p>Methods</p> <p>A total of 114,827 cases were reported using the Taiwan enquiry system between 2002 and 2006; of these, 26,027 (22.7%) were finally diagnosed as not being tuberculosis, 7,005 (8.2%) were diagnosed as extra-pulmonary tuberculosis and 3,677 (3.2%) were not a first-time diagnosis of tuberculosis, and these cases were hence excluded. Diagnosis time was defined as the length of time between the first medical examination (including chest radiography, sputum smear or sputum culture) to the diagnosis of PTB; treatment time was defined as the period from the diagnosis of PTB to the initiation of treatment. Using the cut-off at the 75^thpercentile, a period of longer than 9 days was defined as a <it>diagnosis delay </it>and a period of longer than 2 days as a <it>treatment delay</it>. Multiple logistic regression analysis was applied to analyze the risk factors associated with these delays.</p> <p>Results</p> <p>During the five-year study period, among the 78,118 new PTB patients reported in Taiwan, the mean diagnosis and treatment times were 12 and 5 days and the median times 1 day and 0 days, respectively. In total, 24.9% of the new PTB patients' diagnosis time delays were longer than 9 days and 20.3% of the patients' treatment time delays were longer than 2 days. The main factors associated with diagnosis delay included age, reporting year, living with family and a positive sputum culture (<it>p </it>< 0.0001); the risk factors significantly associated with treatment delay were increased age, an aboriginal ethnic background, a positive sputum culture and diagnosis at a non-medical center (<it>p </it>< 0.0001).</p> <p>Conclusion</p> <p>The Taiwan TB reporting enquiry system has successfully increased the confirmed PTB reporting rate from 64.4% to 71.5%. Greater age and a positive sputum culture were both found to significantly increase both diagnosis and treatment delays; treatment delay is also significantly affected by the patient having an aboriginal ethnic background and being diagnosed at a non-medical center.</p

GLUT1 gene is a potential hypoxic marker in colorectal cancer patients

<p>Abstract</p> <p>Background</p> <p>Tumor hypoxia is an important factor related to tumor resistance to radiotherapy and chemotherapy. This study investigated molecules synthesized in colorectal cancer cells during hypoxia to explore the possibility of developing molecular probes capable of detecting cell death and/or the efficiency of radiotherapy and chemotherapy.</p> <p>Methods</p> <p>At first, we incubated two human colorectal adenocarcinoma cell lines SW480 (UICC stage II) and SW620 (UICC stage III) cells in hypoxic (≤2% O₂, 93% N₂, and 5% CO₂) and normoxic conditions (20% O₂, 75% N₂, and 5% CO₂) for 24 h and 48 h. The relative expression ratio of GLUT1 mRNA in hypoxic conditions was analyzed by RT-PCR. Ten cancerous tissues collected from human colorectal cancer patients were examined. HIF-1α and HIF-2α levels were measured to indicate the degree of hypoxia, and gene expression under hypoxic conditions was determined. As a comparison, HIF-1α, HIF-2α, and GLUT1 levels were measured in the peripheral blood of 100 CRC patients.</p> <p>Results</p> <p>Hypoxia-induced lactate was found to be elevated 3.24- to 3.36-fold in SW480 cells, and 3.06- to 3.17-fold in SW620 cells. The increased relative expression ratio of GLUT1 mRNA, under hypoxic conditions was higher in SW620 cells (1.39- to 1.72-fold elevation) than in SW480 cells (1.24- to 1.66-fold elevation). HIF-1α and HIF-2α levels were elevated and GLUT1 genes were significantly overexpressed in CRC tissue specimens. The elevated ratio of GLUT1 was higher in stage III and IV CRC tissue specimens than in the stage I and II (2.97–4.73 versus 1.44–2.11). GLUT1 mRNA was also increased in the peripheral blood of stage II and III CRC patients as compared to stage I patients, suggesting that GLUT1 may serve as a hypoxic indicator in CRC patients.</p> <p>Conclusion</p> <p>In conclusion, this study demonstrated that GLUT1 has the potential to be employed as a molecular marker to indicate the degree of hypoxia experienced by tumors circulating in the blood of cancer patients.</p