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The standard practice to mitigate high-dose methotrexate (HD-MTX)-induced nephrotoxicity (HMN) in acute lymphoblastic leukemia (ALL) is to monitor levels until serum MTX falls below a predefined threshold. It is not feasible in most resource-constrained centers. Literature on the various factors affecting HMN in these centers is limited, retrospective, and heterogeneous. Though hypoalbuminemia has been postulated as a risk factor for HMN, the relationship of undernutrition with HMN has not been studied.This prospective observational study consecutively enrolled children 12 years old with ALL receiving HD-MTX. Children with preexisting renal disease and exposed to nephrotoxic drugs two weeks preceding HD-MTX infusion were excluded. HD-MTX was administered over 24 hours (BFM-2009 protocol) with 12 hours of prehydration. Solitary MTX levels at 36 hours (MTX36) were outsourced, and 6-8 doses of leucovorin were given six-hourly. Hydration was continued till last dose of leucovorin. Various factors affecting HMN (rise in creatinine to 1.5 times baseline) were recorded: age, sex, type of ALL, risk group of ALL, first dose of MTX, dose of MTX, undernourishment, serum protein, and albumin along with C-reactive protein and MTX36 levels.Forty-four children who received 150 HD-MTX cycles were analyzed. HMN was seen in 14% of cycles. On univariate analysis, undernourishment, MTX36 levels, hypoproteinemia, and hypoalbuminemia were significantly associated with HMN. On multivariate analysis, hypoalbuminemia and MTX36 levels significantly predicted the development of HMN with odds ratios of 4.71 and 1.45.Hypoalbuminemia and solitary serum MTX levels predict HMN in centers where serial MTX level monitoring is not feasible.

Earlier research on the biogeochemical factors affecting natural attenuation in coal-tar contaminated groundwater, at South Glens Falls, NY, revealed the importance of anaerobic metabolism and trophic interactions between degrader and bacterivore populations. Field-based characterizations of both phenomena have proven challenging, but advances in stable isotope probing (SIP), single-cell imaging and shotgun metagenomics now provide cultivation-independent tools for their study. We tracked carbon from (13)C-labeled naphthalene through microbial populations in contaminated surface sediments over six days using respiration assays, secondary ion mass spectrometry imaging and shotgun metagenomics to disentangle the contaminant-based trophic web. Contaminant-exposed communities in hypoxic/anoxic groundwater were contrasted with those from oxic surface sediments to identify putative features of anaerobic catabolism of naphthalene. In total, six bacteria were responsible for naphthalene degradation. Cupriavidus, Ralstonia and Sphingomonas predominated at the earliest stages of SIP incubations and were succeeded in later stages by Stenotrophomonas and Rhodococcus. Metagenome-assembled genomes provided evidence for the ecological and functional characteristics underlying these temporal shifts. Identical species of Stenotrophomonas and Rhodococcus were abundant in the most contaminated, anoxic groundwater. Apparent increases in bacterivorous protozoa were observed following exposure to naphthalene, though insignificant amounts of carbon were transferred between bacterial degraders and populations of secondary feeders.

Robust nanoarchitectures based on surfactant-free ultrafine Pd nanoparticles (NPs) (2.7–8.2±0.5 nm) have been developed by using the incipient wetness impregnation method with subsequent reduction of PdII species encaged in the 1,3,5-triazine-functionalized nitrogen-rich porous organic polymer (POP) by employing NaBH4, HCHO, and H2 reduction routes. The Pd-POP materials prepared by the three different synthetic methods consist of virtually identical chemical compositions but have different physical and texture properties. Strong metal–support interactions, the nanoconfinement effect of POP, and the homogeneous distribution of Pd NPs have been investigated by performing 13C cross-polarization (CP) solid-state magic angle spinning (MAS) NMR, FTIR, and X-ray photoelectron spectroscopy (XPS), along with wide-angle powder XRD, N2 physisorption, high-resolution (HR)-TEM, high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), and energy-dispersive X-ray (EDX) mapping spectroscopic studies. The resulting Pd-POP based materials exhibit highly efficient catalytic performance with superior stability in promoting biomass refining (hydrodeoxygenation of vanillin, a typical compound of lignin-derived bio-oil). Outstanding catalytic performance (≈98 % conversion of vanillin with exclusive selectivity for hydrogenolysis product 2-methoxy-4-methylphenol) has been achieved over the newly designed Pd-POP catalyst under the optimized reaction conditions (140 °C, 10 bar H2 pressure), affording a turnover frequency (TOF) value of 8.51 h−1 and no significant drop in catalytic activity with desired product selectivity has been noticed for ten successive catalytic cycles, demonstrating the excellent stability and reproducibility of this catalyst system. A size- and location-dependent catalytic performance for the Pd NPs with small size (1.31±0.36 and 2.71±0.25 nm) has been investigated in vanillin hydrodeoxygenation reaction with our newly designed Pd-POP catalysts. The presence of well-dispersed electron-rich metallic Pd sites and highly rigid cross-linked amine-functionalized POP framework with high surface area is thought to be responsible for the high catalytic activity and improvement in catalyst stability.

An efficient heterogeneous catalytic method for oxidative amination of azoles with amines have been developed. This environmentally benign amination reaction was carried out without using any external base or acid, only molecular oxygen was used as a green oxidant. The catalyst is easy to separate from the reaction mixture and can be reused for several times. The aminated azoles are important pharmacophore with biological activity.

A transition metal free highly regioselective remote C−H halogenation has been developed. Oxidative halogenation (Cl, Br, I) of C5-H of 8-amido quinolone with inexpensive potassium persulfate as an oxidant and cheap halogenating agents like N-halosuccinimide (NXS) or tetrabutylammonium halides (TBAX) were employed. Two reaction conditions were developed and in both routes have advantages such as C5-selectivity, high to excellent yields (up to 98 %) and broad substrate scope. The reaction also carried out in water, open to air condition.

In the presence of molecular oxygen, a {001}-faceted nanocrystalline anatase TiO2 catalyst enabled the selective oxidation of nonactivated aliphatic alcohols to the corresponding aldehydes or ketones under visible light. The reaction shows excellent conversion and selectivity towards the formation of the carbonyl products without over-oxidation to the corresponding carboxylic acids. The exceptional reactivity of the catalyst is possibly due to the absorption of visible light originating from a stronger interaction of alcohol with the {001} facet, which facilitates the modification of the band structure of TiO2, thus facilitating the photogenerated hole transfer and subsequent oxidation processes. The experimental results have also been corroborated by first-principles quantum chemical DFT calculations.

Summary The development of pedotransfer functions (PTFs) needs to recognize and account appropriately for the underlying structure in data that is imposed by the sampling design adopted to ensure that the data support any scientific inferences. We fitted several potential PTFs for field capacity (FC) and permanent wilting point (PWP), with and without taking account of the sampling design, to data collected with a nested spatial sampling design. Leave-one-paddock-out cross-validation (LOPOCV) and the Akaike information criterion (AIC) were used to identify PTFs with strong predictive performance. The results suggest that cross-validation statistics appear to provide no additional useful information on the predictive performance of PTFs beyond that provided by the AIC and other model fitting statistics that, in contrast to LOPOCV, are based on the entire dataset. Results further suggest that PTFs derived with the sampling design accounted for had consistently smaller AICs and potentially better predictive performance than when no account was taken. We identified eight PTFs for FC and six PTFs for PWP with strong predictive performance for soil used for dryland cropping in Victoria that were derived from routinely measured soil data with the sampling design taken into account. Highlights Derivation of PTFs should be based on appropriate analysis of data that accounts for the underlying structure in data. A linear mixed effects modelling approach to derive PTFs is proposed that takes account of a nested sampling design. The PTFs derived with sampling design accounted for had consistently stronger predictive performance. Derivation of PTFs should account for the underlying structure in data with appropriate linear mixed effects models.

Hetereogeneous γ-MnO2 Catalyzed Redox Reaction of o-Nitrophenol with Benzyl Alcohols/ benzyl amines for the synthesis of 2-Arylbenzoxazoles is described here. Surface active Mn+3 species and the surface O−& O2− species were found to play an important role in the catalytic activity. Catalyst is easy to prepare, economic and can be reused for several times. The procedure is very simple and general and applicable for wide range of substrates to afford 2-aryl benzoxazole in good to excellent yield.

Cn-AMP2 is an antimicrobial peptide derived from liquid endosperm of coconut (Cocos nucifera). It consists of 11 amino acid residues and predicted to have high propensity for β-sheet formation that disposes this peptide to be amyloidogenic. In the present study, we have examined the amyloidogenic propensities of Cn-AMP2 in silico and then tested the predictions under in vitro conditions. The in silico study revealed that the peptide possesses high amyloidogenic propensity comparable with Aβ. Upon solubilisation and agitation in aqueous buffer, Cn-AMP2 forms visible aggregates that display bathochromic shift in the Congo red absorbance spectra, strong increase in thioflavin T fluorescence and fibrillar morphology under transmission electron microscopy. All these properties are typical of an amyloid fibril derived from various proteins/peptides including Aβ.

Amyloid aggregates display striking features of detergent stability and self-seeding. Human serum albumin (HSA), a preferred drug-carrier molecule, can also aggregate in vitro. So far, key amyloid properties of stability against ionic detergents and self-seeding, are unclear for HSA aggregates. Precautions against amyloid contamination would be required if HSA aggregates were self-seeding. Here, we show that HSA aggregates display detergent sarkosyl stability and have self-seeding potential. HSA dimer is preferable for clinical applications due to its longer retention in circulation and lesser oedema owing to its larger molecular size. Here, HSA was homodimerized via free cysteine-34, without any potentially immunogenic cross-linkers that are usually pre-requisite for homodimerization. Alike the monomer, HSA dimers also aggregated as amyloid, necessitating precautions while using for therapeutics.

Heterogeneous Cu-MnO-catalyzed selective monohalogenation of aromatic compounds with cheap N-halosuccinimide (NXS) as a halogenating agent in the presence of molecular oxygen as an oxidant, under irradiation with visible light is reported. Monochlorination, bromination, and iodinations were achieved in a highly selective fashion. Our developed heterogeneous Cu-MnO catalyst without any additive and ligands works well for halogenation with electron-rich substrates and also works selectively with electron poor substrates. Moreover, chlorination occurs efficiently with the more challenging substrates benzoic esters. The heterogeneous nature of the reaction was proven by hot filtration test.