Heterometallic CuII/LnIII polymers active in the catalytic aerobic oxidation of cycloalkenes under solvent-free conditions

Heterometallic 3d-4f inorganic polymers were prepared using 3,5 pyridinedicarboxylic acid (H2PDC), {[CuLn2(PDC)2(SO4)2(H2O)6]·H2O}n (Ln: SmIII, CuSmPDC, EuIII, CuEuPDC, GdIII, and CuGdPDC). These catalysts are active in the aerobic oxidation of cycloalkenes under solvent-free conditions, with a conversion for the oxidation of cyclohexene of 71% after one hour of the reaction, and a TOF value of 1438 h-1 for CuSmPDC. On the other hand, the oxidation of cycloheptene and cyclooctene exhibited slightly lower conversions of 52% and 47%, and TOF values of 1053 and 159 h-1 after 1 and 6 hours of the reaction, respectively. The radical mechanism for the oxidation reaction of cyclohexene was assessed by Raman and EPR spectroscopy. The first evidenced the formation of Cu-O2 adducts and the second permitted is to observe the presence of the oxygen centered radical species, which act as initiators of the reaction chain to generate the products. An increase in the temperature of the reaction correlates with the adduct formation, and with the enhancement of the oxidation reaction.

Bile acid-FXRα pathways regulate male sexual maturation in mice

The bile acid receptor Farnesol-X-Receptor alpha (FRXα) is a member of the nuclear receptor superfamily. FRXα is expressed in the interstitial compartment of the adult testes, which contain the Leydig cells. In adult, short term treatment (12 hours) with FRXα agonist inhibits the expression of steroidogenic genes via the induction of the Small heterodimer partner (SHP). However the consequences of FRXα activation on testicular pathophysiology have never been evaluated. We demonstrate here that mice fed a diet supplemented with bile acid during pubertal age show increased incidence of infertility. This is associated with altered differentiation and increase apoptosis of germ cells due to lower testosterone levels. At the molecular level, next to the repression of basal steroidogenesis via the induction expression of Shp and Dax-1, two repressors of steroidogenesis, the main action of the BA-FRXα signaling is through lowering the Leydig cell sensitivity to the hypothalamo-pituitary axis, the main regulator of testicular endocrine function. In conclusion, BA-FRXα signaling is a critical actor during sexual maturation.

What will freestanding borophene nanoribbons look like? An analysis of their possible structures, magnetism and transport properties

The geometry, magnetism and electronic transport properties of nanoribbons made of the boron-based analogue of graphene are studied.

Structure, fragmentation patterns, and magnetic properties of small nickel oxide clusters

We report a comprehensive theoretical study of the structural and electronic properties of neutral and charged nickel oxide clusters, Ni_nO_m^0/± (n = 3–8 and m = 1–10), in the context of recent experiments of photodissociation and Ion Mobility Mass Spectrometry.

Radial Scar and Tubular Carcinoma

Clinical, mammographic, sonographic and pathologic examinations in 17 patients with nonpalpable stellate lesions showed radiographic findings suggestive of radial scars, with the exception of 2 cases which showed a dense central region. These findings were not sufficiently consistent to differentiate radial scar from carcinoma so that wire localization biopsy was necessary. Four patients had 7 radial scars associated with 6 tubular carcinomas, 2 of them having 3 and 2 radial scars with 2 tubular carcinomas, respectively. No characteristic radiographic findings were made in these cases. Four patients showed radial scar with punctate microcalcifications in the surrounding breast parenchyma as part of benign and premalignant conditions. Ultrasonography in 7 patients showed a hypoechoic area on 4 with acoustic shadow similar to that of carcinoma. Our study suggested that radial scar has a relationship with tubular carcinoma and surgical excision of these stellate lesions is, therefore, required.

Nonpalpable Breast Lesion

One hundred and fifty-six patients with suspect nonpalpable breast lesion underwent stereotaxic core needle aspiration biopsy (SCNAB) with a single pass in an upright “add-on” stereotaxic device using a manual 1.6-mm needle (16 G), to determine whether the results were comparable to results of SCNAB with a multiple-pass technique. Of the 69 carcinomas, 51 (74%) were correctly diagnosed and definitive surgical therapy, without surgical biopsy, was performed in 42 of the 50 invasive carcinomas (84%) and in 9 of the 19 noninvasive carcinomas (47%). Ten noninvasive carcinomas and 4 invasive carcinomas, discovered by microcalcifications or distortion on the mammograms, form 78% of the false-negative results. There were no false-positive results. Vasovagal reactions occurred in 11% of the procedures. Although the results were acceptable in patients with invasive carcinoma, more than one needle pass is necessary for greater diagnostic accuracy of SCNAB, especially in patients with only microcalcifications or distortion on the mammogram.

Implementing Algorithm-Guided Warfarin Dosing in an Ethnically Diverse Patient Population Using Electronic Health Records and Preemptive CYP2C9 and VKORC1 Genetic Testing

Implementation of pharmacogenetic-guided warfarin dosing has been hindered by inconsistent results from reported clinical trials and a lack of available algorithms that include alleles prevalent in non-white populations. However, current evidence indicates that algorithm-guided dosing is more accurate than empirical dosing. To facilitate multiethnic algorithm-guided warfarin dosing using preemptive genetic testing, we developed a strategy that accounts for the complexity of race and leverages electronic health records for algorithm variables and deploying point-of-care dose recommendations.

Spin-polarized transport in hydrogen-passivated graphene and silicene nanoribbons with magnetic transition-metal substituents

We present a systematic theoretical study of the electronic transport in hydrogen passivated zigzag graphene and silicene nanoribbons with between zero and four neighboring H atoms on one edge replaced by magnetic transition metals (Fe, Co, and Ni). The calculations were performed using equilibrium transport and density-functional theory with the generalized gradient approximation to exchange and correlation. We considered the magnetic moments of the two edges aligned both ferromagnetically (Ferro-F form) and antiferromagnetically (Ferro-A form). The Ferro-A graphene-based ribbons were all semiconducting and would support moderate spin-polarized currents of either sign by applying positive or negative gate voltages. The Ferro-F graphene-based ribbons were all metallic; the most interesting for possible spintronic applications being that with a single Ni atom, in which strong spin-filtering at low bias resulted from a deep trough in the transmission of one spin component around the Fermi level. By contrast, in the Si-based analog this trough was split, partially eliminating the polarization of the current. This splitting was found to be related to the buckled structure of the Si-based nanoribbon, which has its origin in its preference for sp(3)-like hybridization.

Crescentic glomerulonephritis: data from the Spanish Glomerulonephritis Registry

BACKGROUND

Crescentic glomerulonephritis (CGN) is a histological finding that implies rapid deterioration of renal function and can be related to different diseases, such as type 1 or anti-glomerular basement membrane antibody (Goodpasture) disease, type 2 or immune complex CGN and type 3 or pauci-immune disease.

AIM

The present study describes CGN and its characteristics based on the data from the Spanish Glomerulonephritis Registry.

METHODS

An analysis was made of all native renal biopsies obtained from patients during 1994-2013 and classified as CGN. A patient epidemiological and clinical data questionnaire was completed by the 120 centres involved.

RESULTS

A total of 21,774 biopsies was performed, of which 2089 (8.1%) corresponded to CGN (211 type 1, 177 type 2 and 1701 type 3). Renal function was poorer in type 1 compared with types 2 and 3, and proteinuria was higher in type 2 compared to types 1 and 3. Patients diagnosed with CGN type 3 were older than those with types 1 and 2, but less hypertensive than the type 2 patients. No differences in the urine test findings were found between types 1 and 2. Microhaematuria was the most frequent feature in general, as well as in type 3 compared with types 1 and 2. The main indication for biopsy was acute renal injury. Age was the only difference between type 1 patients with and without alveolar haemorrhage (53 [33-67] vs 64 [46-73], P = 0.008).

CONCLUSION

Although classified as the same entity, the different types of CGN have different features that must be taken into account.