Ruthenium on phosphorous-modified alumina as an effective and stable catalyst for catalytic transfer hydrogenation of furfural

Supported ruthenium was used in the liquid phase catalytic transfer hydrogenation of furfural. To improve the stability of Ru against leaching, phosphorous was introduced on a Ru/Al₂O₃ based catalyst upon impregnation with ammonium hypophosphite followed by either reduction or calcination to study the effect of phosphorous on the physico-chemical properties of the active phase. Characterization using X-ray diffraction, solid state ³¹P nuclear magnetic resonance spectroscopy, X-ray absorption spectroscopy, temperature programmed reduction with H₂, infrared spectroscopy of pyridine adsorption from the liquid phase and transmission electron microscopy indicated that phosphorous induces a high dispersion of Ru, promotes Ru reducibility and is responsible for the formation of acid species of Brønsted character. As a result, the phosphorous-based catalyst obtained after reduction was more active for catalytic transfer hydrogenation of furfural and more stable against Ru leaching under these conditions than a benchmark Ru catalyst supported on activated carbon.

Phosphorous induces structural changes in Ru/Al₂O₃ that make it more active and more stable for liquid phase hydrogenation of furfural.     

Determination of 1-phenyl-2-propanone (P2P) by HS-GC/MS in a material sold as “wet amphetamine”

In this paper, we describe the approach to the characterization of an unusual material seized by the judicial authority, near Brescia City in Northern Italy. Usual analyses such as thin-layer chromatography, gas chromatography (GC)–flame ionization detection, and GC/mass spectrometry (MS) did not show the presence of drugs of abuse, in particular amphetamine-like compounds. The major solid component was identified as cornstarch; then taking into account the strong aromatic scent of the seized material; a preliminary experiment for volatile organic compounds was carried out by headspace (HS)-GC/MS. This analysis tentatively evidenced the presence of 1-phenyl-2-propanone (P2P), an amphetamine precursor. Therefore, we developed and optimized a new analytical method for determination of P2P in seized materials by HS-GC/MS. We also synthesized P2P, with the permission of the Ministry of Health, to have it as reference standard, because of its being illegal and the difficulty in obtaining it. This case had some analogies with the cases referred to as “wet amphetamine” by the judicial authority, in which amphetamines are sold mixed with P2P. The possible use of the material could be the production of tablets made of cornstarch with an aromatic scent similar to that of amphetamines to deceive consumers and to sell them as a drug of abuse.     

Human sperm express a functional androgen receptor: effects on PI3K/AKT pathway

BACKGROUND: Results from mice lacking the androgen receptor (AR) showed that it is critical for the proper development and function of the testes. The aim of this study was to investigate whether a functional AR is present in human sperm. METHODS: The expression of AR and its effects on sperm were evaluated by RT-PCR, Western Blot, Immunocytochemistry, PI3Kinase and DNA laddering assays. RESULTS: We showed in human sperm that AR is located at the head region. Dihydrotestosterone (DHT), in a dose-dependent manner, leads to the rapid phosphorylation of the AR on tyrosine, serine and threonine residues and this effect was reduced by the AR antagonist hydroxyflutamide (OH-Flut). The effects of AR were evaluated on the phosphoinositide-3 kinase/protein kinase B (PI3K/AKT) pathway. Specifically, 0.1 and 1 nM DHT stimulated PI3K activity, whereas 10 nM DHT decreased PI3K activity and levels of p-AKT S473 and p-AKT T308, p-BCL2, and enhanced phosphatase and tensin homologue (PTEN) phosphorylation. In addition, 10 nM DHT was able to induce the cleavage of caspases 8, 9 and 3 and cause DNA laddering, and these effects were reversed either by casodex or OHFlut. By using wortmannin, a specific PI3K inhibitor, the cleavage of caspase 3 was reproduced, confirming that in sperm the PI3K/AKT pathway is involved in caspase activation. CONCLUSIONS: Human sperm express a functional AR that have the ability to modulate the PI3K/AKT pathway, on the basis of androgen concentration.     

Opioids and renal function.

Opioids, both endogenous and exogenous, have a strong influence on the renal function through different mechanisms, producing changes in the renal excretion of water and sodium. Several studies have demonstrated that opioids influence renal function, according to the agonist profile used. Mu, kappa, and delta agonists produce different renal effects, although the mechanisms remain unclear. Experimental data have given the input for a possible therapeutic role of kappa agonists for some specific conditions, for example, in treating water retention or hyponatremia occurring in patients who have hepatic cirrhosis with ascites. On the other hand, changes in renal function might strongly condition the use of opioids in the clinical setting, and the knowledge of the relationship between opioids and renal function is mandatory for a tailored approach to accommodate the individual responses in terms of pain intensity, tolerance, and adverse effects experienced by these groups of patients. The influence of renal function when using different opioids in the clinical setting is reviewed, as well as problems related to transplantation, renal damage induced by opioid addiction, and problems related to the use of opioid antagonists in such conditions. PERSPECTIVE: Endogenous opioids exert physiologic effects on renal function, and the use of opioids may have an influence on renal activity. Renal impairment has a serious impact on the clearance of most opioids used in the clinical setting. Biochemical and clinical monitoring is mandatory to prevent serious complications.