Catalytic α-Hydroarylation of Acrylates and Acrylamides via an Interrupted Hydrodehalogenation Reaction

The palladium-catalyzed, α-selective hydroarylation of acrylates and acrylamides is reported. Under optimized conditions, this method is highly tolerant of a wide range of substrates including those with base sensitive functional groups and/or multiple enolizable carbonyl groups. A detailed mechanistic study was undertaken, and the high selectivity of this transformation was shown to be enabled by the formation of a [PdII(Ar)(H)] intermediate, which performs selective hydride insertion into the β-position of α,β-unsaturated carbonyl compounds.

Diverticulitis in HIV-infected patients within the United States

OBJECTIVES

Diverticulitis in patients on immunosuppressant therapy has been associated with increased mortality, but there are no data for HIV-infected patients. Our aim was to compare the outcomes of hospitalizations for diverticulitis in patients with and without HIV infection.

METHODS

Cross-sectional study of hospitalizations in the United States accessed through the Nationwide Inpatient Sample, Healthcare Cost and Utilization Project. Patients hospitalized for diverticulitis in 2007-2011 were included in the analysis. The primary outcomes of interest were mortality and surgical therapy rates. Patients from 2003 to 2011 were utilized to analyse trends in prevalence.

RESULTS

There were 2375 patients with HIV infection hospitalized for diverticulitis and 1 160 391 patients without HIV infection hospitalized for diverticulitis from 2007 to 2011. The patients with HIV infection were younger and more likely to be male and nonwhite (P < 0.001 for all). There were also differences in insurance types (P < 0.001) and hospitals [size (P = 0.008), type (P < 0.001) and location (P < 0.001)]. After multivariate analysis, patients with diverticulitis and HIV infection had a significantly increased in-hospital mortality rate [odds ratio (OR) 3.94 (95% confidence interval, CI, 1.52-10.20)] and a lower rate of surgical intervention [OR 0.74 (95% CI 0.57-0.95)]. From 2003 to 2011, there was a linear increasing trend in the prevalence of HIV infection among patients hospitalized for diverticulitis (P < 0.001).

CONCLUSIONS

HIV-infected patients with diverticulitis had increased mortality and received less surgical treatment in comparison to the general population. Diverticulitis in HIV-infected patients increased in prevalence over the study period.

Prevalence, treatment, and outcomes of the hepatic artery stenosis after liver transplantation

INTRODUCTION

Hepatic artery stenosis (HAS) after liver transplantation can lead to altered hepatic function and/or thrombosis, there by increasing morbidity and mortality. The prevalence of HAS in the literatures varies from 4% to 11%.

OBJECTIVE

We sought to describe the prevalence and treatment of hepatic artery stenosis.

METHODS

We performed a descriptive retrospective analysis of 253 liver transplantations from March 1998 to May 2007, including patients with suspected HAS owing to increased hepatic enzymes, altered Doppler ultrasound (us) and hepatic biopsy. The confirmation of HAS was achieved through areriography.

RESULTS

Nine patients were identified to have HAS, a 3.5% prevalence. Among the HAS patients, seven were male and two female. Their average age was 35.5 years (range, 65 to 53). The average time between the diagnosis and transplantation was 14.2 months (range, 9 to 68). The increase in hepatic enzymes among this group averaged: aspartate aminotransferase 131 U/L (range, 26 to 412) and alanine aminotransferase 192 U/L (range, 35 to 511). Doppler US showed alteration in the resistance level index. All patients underwent areriography; only one could not be treated owing to severe hepatic artery spasm, which also occurred during another attempt weeks after the first one. Among the eight patients, six were treated with stents and two with angioplastis. All treated patients displayed improvements in parameters. Four patients treated with stents required retreatment: two underwent angioplasty and two, a thrombolytic. One graft rethrombosed but evolved in compensated fashion with recanalization by collaterals. There has been no graft loss or mortality in this population. The average time of posttreatment follow-up was 31.28 (range, 9 to 68) months.

CONCLUSION

The prevalence of HAS in our unit was within that reported in the literature. Treatment with a stent or angioplasty proved to be efficient to control this complication, considering that hepatic function recovered and that there was neither graft nor patient loss.

Prevalence, treatment, and outcomes of the hepatic artery stenosis after liver transplantation

INTRODUCTION

Hepatic artery stenosis (HAS) after liver transplantation can lead to altered hepatic function and/or thrombosis, there by increasing morbidity and mortality. The prevalence of HAS in the literatures varies from 4% to 11%.

OBJECTIVE

We sought to describe the prevalence and treatment of hepatic artery stenosis.

METHODS

We performed a descriptive retrospective analysis of 253 liver transplantations from March 1998 to May 2007, including patients with suspected HAS owing to increased hepatic enzymes, altered Doppler ultrasound (us) and hepatic biopsy. The confirmation of HAS was achieved through areriography.

RESULTS

Nine patients were identified to have HAS, a 3.5% prevalence. Among the HAS patients, seven were male and two female. Their average age was 35.5 years (range, 65 to 53). The average time between the diagnosis and transplantation was 14.2 months (range, 9 to 68). The increase in hepatic enzymes among this group averaged: aspartate aminotransferase 131 U/L (range, 26 to 412) and alanine aminotransferase 192 U/L (range, 35 to 511). Doppler US showed alteration in the resistance level index. All patients underwent areriography; only one could not be treated owing to severe hepatic artery spasm, which also occurred during another attempt weeks after the first one. Among the eight patients, six were treated with stents and two with angioplastis. All treated patients displayed improvements in parameters. Four patients treated with stents required retreatment: two underwent angioplasty and two, a thrombolytic. One graft rethrombosed but evolved in compensated fashion with recanalization by collaterals. There has been no graft loss or mortality in this population. The average time of posttreatment follow-up was 31.28 (range, 9 to 68) months.

CONCLUSION

The prevalence of HAS in our unit was within that reported in the literature. Treatment with a stent or angioplasty proved to be efficient to control this complication, considering that hepatic function recovered and that there was neither graft nor patient loss.

Direct administration of interleukin-1 and interferon-gamma to rat pancreas leads to the in vivo production of nitric oxide and expression of inducible nitric oxide synthase and inducible cyclooxygenase

INTRODUCTION

Proinflammatory cytokines may play a pivotal role in the pathogenesis of insulin-dependent diabetes mellitus (IDDM). In vitro, the formation of nitric oxide (NO) catalyzed by inducible NO synthase (iNOS) has been shown to be involved in the cytotoxic effects of cytokines on pancreatic beta cells. Cytokines have also been shown to cause the expression of inducible cyclooxygenase (COX-2) in isolated islets.

AIMS

To describe a novel in vivo model that allows investigation of the effects of direct cytokine administration to the pancreas.

METHODOLOGY AND RESULTS

By using this method, we demonstrate that administration of interleukin-1beta and interferon-gamma to rat pancreas results in the generation of NO in the treated pancreata as detected by NO trapping and electron paramagnetic resonance spectroscopy. Beta cells were identified as the source of the formed NO. Reverse transcription and polymerase chain reaction analyses showed that administration of cytokines to the pancreas leads to the expression of iNOS and COX-2 mRNA in the pancreas tissue as well as the islets isolated from such tissues. The compound phenyl N-tert-butylnitrone, which protects mice against streptozotocin-induced IDDM, inhibits NO formation and downregulates both iNOS and COX-2 mRNA levels.

Inhibition of the cytokine-mediated inducible nitric oxide synthase expression in rat insulinoma cells by phenyl N-tert-butylnitrone

Cytokines and nitric oxide (NO) have been implicated in the pathogenesis of insulin-dependent diabetes mellitus (IDDM). We have shown that the spin-trapping agent phenyl N-tert-butylnitrone (PBN) protects against streptozotocin (STZ)-induced IDDM in mice. In order to gain more insights into the mechanism(s) of the protective action of PBN against IDDM, we have investigated the effect of this compound on the cytokine-induced NO generation (measured as nitrite) in rat insulinoma RIN-5F cells. Our results demonstrate that PBN cotreatment prevents the generation of nitrite by RIN-5F cells induced by treatment with tumor necrosis factor-alpha, interleukin 1beta, and interferon-gamma in a dose-dependent fashion. The generation of NO as a result of cytokine treatment and the inhibitory effect of PBN were further confirmed by electron paramagnetic resonance spectroscopy. Aminoguanidine, a selective inhibitor of inducible nitric oxide synthase (iNOS), abolished the cytokine-induced nitrite generation whereas N-nitro-l-arginine, an inhibitor more selective for other NOS isoforms, was significantly less effective. Western and Northern analyses demonstrated that PBN inhibits the cytokine-mediated expression of iNOS at the transcriptional level. Cytokine-induced nitrite formation was also inhibited by the two antioxidant agents alpha-lipoic acid and N-acetylcysteine. These results indicate that PBN protects against IDDM at least in part by prevention of cytokine-induced NO generation by pancreatic beta-cells.