, first congeneric with the myrtle rust pathogen .

In 1895 and 2001, rust fungi affecting trees (Chrysobalanchaceae) in Brazil were described as by Hennings in the state of Goiás and as by Ferreira et al. in the state of Amazonas, respectively. Recently, a rust fungus collected close to the Amazonian type location sharing symptoms with the former two species was subjected to morphological examinations and molecular phylogenetic analyses using 28S nuc rDNA (ITS2-28S) and cytochrome oxidase subunit III (CO3) gene sequences.

ALL-tRNAseq enables robust tRNA profiling in tissue samples.

Transfer RNAs (tRNAs) are small adaptor RNAs essential for mRNA translation. Alterations in the cellular tRNA population can directly affect mRNA decoding rates and translational efficiency during cancer development and progression. To evaluate changes in the composition of the tRNA pool, multiple sequencing approaches have been developed to overcome reverse transcription blocks caused by the stable structures of these molecules and their numerous base modifications.

Retarding mechanism of Zn species in geopolymer material using Raman spectroscopy and DFT calculations.

Geopolymers are the most promising alternative to Ordinary Portland Cement for oil-well cementing and well abandonment. To that end, the slurry needs a required pumping time ensured by the addition of retarders. Although zinc has been widely known to prolong the setting time of geopolymers, its mechanism of action has yet to be fully elucidated.

Dual action of pyroligneous acid in the eco-friendly synthesis of bactericidal silver nanoparticles.

In the present study, we demonstrate that pyroligneous acid (PA), also known as wood vinegar, functions efficiently as both reducing and stabilizing agent in the synthesis of silver nanoparticles (AgNPs). The synthesis and stabilization of AgNPs take place in the following fashion: 1) in alkaline environment, oxygenated species (phenols in the present case) contained in PA reduce silver ions to metallic silver; 2) acetic acid, abundantly present in PA, adsorb onto the AgNPs conferring electrostatic stabilization. This mechanism is supported by GC-MS and RAMAN analysis, with the former revealing the compounds lacking in PA after nanoparticle synthesis and the latter demonstrating acetic acid adsorbed on the nanoparticles.

First report of Fusarium kalimantanense causing Fusarium wilt on banana tree in Brazil.

Banana (Musa spp.) is the second most-consumed fruit in Brazil, the fourth-largest producer globally, with 7 million tons in 2021 (IBGE 2021). Studies about the morphological and pathogenic characteristics revealed that the etiology of Fusarium wilt in banana cultivars in Brazil had been related to the Fusarium oxysporum f.

Pyroligneous acid and antibacterial activity: criticism of a paper by Araújo et al. (2018).

Aims: A paper by Araújo et al. (2018) claims that a variety of compounds present in pyroligneous acid (guaiacol, phenols and furfural) are responsible for the observed antimicrobial activity. We show, on the other hand, that the low pH due to acetic acid present in pyroligneous acid is the real cause of the activity.

Biospectroscopy and chemometrics as an analytical tool for comparing the antibacterial mechanism of silver nanoparticles with popular antibiotics against Escherichia coli.

Despite the fact that silver nanoparticles (AgNPs) have been widely studied in medical and correlated fields, details on their mechanisms are yet to be fully understood. Herein we present the first study on the combination of infrared spectroscopy and chemometrics as an analytical tool to investigate the mechanism of action of AgNPs against Escherichia coli by comparison with popular and commercially available antibiotics. The rationale behind this study is that the selected antibiotics act on bacteria in specific and distinct manners (DNA, cell membrane, mitochondria, etc.

Effect of Gold Nanoparticle on 5-Fluorouracil-Induced Experimental Oral Mucositis in Hamsters.

Background: Oral mucositis (OM) is a severe inflammation of the oral mucosal cells associated with chemotherapy and/or radiotherapy-induced toxicity, resulting in epithelial ulcers and higher risk of death from sepsis. The aim of the present study was to evaluate the nanoparticle (AuNp) effect on OM induced in hamsters.

Materials And Methods: 5-fluorouracil (5FU) was used on the first and second day of the experimental model in Golden sirian hamsters, and on the fourth day, mechanical trauma was applied to induce OM.

Rutin-modified silver nanoparticles as a chromogenic probe for the selective detection of Fe in aqueous medium.

The development of nanoprobes for selective detection of metal ions in solution has attracted great attention due to their impact on living organisms. As a contribution to this field, this paper reports the synthesis of silver nanoparticles modified with rutin in the presence of ascorbic acid and their successful use as a chromogenic probe for the selective detection of Fe in aqueous solution. Limits of detection and quantification were found to be 17 nmol L and 56 nmol L, respectively.

Co-culture of Human Stem Cell Derived Neurons and Oligodendrocyte Progenitor Cells.

Crosstalk between neurons and oligodendrocytes is important for proper brain functioning. Multiple co-culture methods have been developed to study oligodendrocyte maturation, myelination or the effect of oligodendrocytes on neurons. However, most of these methods contain cells derived from animal models.

Astrocyte Subtype Vulnerability in Stem Cell Models of Vanishing White Matter.

Objective: Astrocytes have gained attention as important players in neurological disease. In line with their heterogeneous character, defects in specific astrocyte subtypes have been identified. Leukodystrophy vanishing white matter (VWM) shows selective vulnerability in white matter astrocytes, but the underlying mechanisms remain unclear.

Processing of nanomaterials in Layer-by-Layer films: Potential applications in (bio)sensing and energy storage.

Abstract: The study and preparation of new nanostructures involving the integration of distinct nanomaterials have been important for the development of new electrochemical devices for (bio)sensing and energy storage. Such devices envisage miniaturized or flexible electronic equipment for emerging technologies, including adaptive displays, artificial skin and wearable devices. In this way, the processing of specific nanomaterials may lead to nanostructures with properties that permit the fabrication of multifunctional devices for different applications, including sensors and supercapacitors.

Neuron-Glia Interactions Increase Neuronal Phenotypes in Tuberous Sclerosis Complex Patient iPSC-Derived Models.

Tuberous sclerosis complex (TSC) is a rare neurodevelopmental disorder resulting from autosomal dominant mutations in the TSC1 or TSC2 genes, leading to a hyperactivated mammalian target of rapamycin (mTOR) pathway, and gray and white matter defects in the brain. To study the involvement of neuron-glia interactions in TSC phenotypes, we generated TSC patient induced pluripotent stem cell (iPSC)-derived cortical neuronal and oligodendrocyte (OL) cultures. TSC neuron mono-cultures showed increased network activity, as measured by calcium transients and action potential firing, and increased dendritic branching.

Patterning factors during neural progenitor induction determine regional identity and differentiation potential in vitro.

The neural tube consists of neural progenitors (NPs) that acquire different characteristics during gestation due to patterning factors. However, the influence of such patterning factors on human pluripotent stem cells (hPSCs) during in vitro neural differentiation is often unclear. This study compared neural induction protocols involving in vitro patterning with single SMAD inhibition (SSI), retinoic acid (RA) administration and dual SMAD inhibition (DSI).

On the synergy between silver nanoparticles and doxycycline towards the inhibition of growth.

In a previous paper (, 2015, , 66886-66893), we showed that the combination of silver nanoparticles (NanoAg) with doxycycline (DO) culminated in an increased bactericidal activity towards . Herein we further investigated the metabolic changes that occurred on upon exposure to NanoAg with the help of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) coupled with multivariate data analysis. It has been discovered that the combination of DO with NanoAg produced metabolic changes in that were not simply the overlap of the treatments with DO and NanoAg separately.

Apoptosis in human liver carcinoma caused by gold nanoparticles in combination with carvedilol is mediated via modulation of MAPK/Akt/mTOR pathway and EGFR/FAAD proteins.

In cancers, apoptosis signaling pathways and cell survival and growth pathways responsible for resistance to conventional treatments, such as Pi3K/Akt/mTOR and mitogen-activated protein kinase (MAPK) become dysregulated. Recently, alternative treatments to promote tumor cell death have become important. The present study reports on the antitumor and cytoprotective action of gold nanoparticles (GNPs) and carvedilol in combination and in isolated application.

Anti-inflammatory, analgesic and anti-tumor properties of gold nanoparticles.

Background: Gold nanoparticles (GNPs) are regarded as potential platforms for drug delivery. However, their interaction with live organisms must be understood prior to their utilization as drug carriers. The present study reports the anti-inflammatory, analgesic and anti-tumor effects of GNPs.

Virulence and genetic diversity among isolates of Mycosphaerella fijiensis in two regions of Brazil.

Black sigatoka, caused by the fungus Mycosphaerella fijiensis (anamorphic stage: Paracercospora fijiensis), was first detected in Brazil in early 1998 in the Benjamin Constant and Tabatinga municipalities in the State of Amazonas, near to where the borders of Brazil, Colombia, and Peru converge. Understanding how cultivars react to the pathogen, and characterizing the genetic variability of isolates from two distant and distinct banana-producing regions, are important for determining the virulence of M. fijiensis.

Body composition as a frailty marker for the elderly community.

Background: Body composition (BC) in the elderly has been associated with diseases and mortality; however, there is a shortage of data on frailty in the elderly.

Objective: To investigate the association between BC and frailty, and identify BC profiles in nonfrail, prefrail, and frail elderly people.

Methods: A cross-sectional study comprising 235 elderly (142 females and 93 males) aged ≥65 years, from the city of Amparo, State of São Paulo, Brazil, was undertaken.

New insights into the formation mechanism of Ag, Au and AgAu nanoparticles in aqueous alkaline media: alkoxides from alcohols, aldehydes and ketones as universal reducing agents.

In this report we present new insights into the formation mechanism of Ag, Au and AgAu nanoparticles with alcohols, aldehydes and ketones in alkaline medium at room temperature. We selected methanol, ethanol, glycerol, formaldehyde, acetaldehyde and acetone to demonstrate their capability of reducing gold and silver ions under the above-mentioned conditions. We showed that the particles are also formed with potassium tert-butoxide in the absence of hydroxides.

Genetic diversity of Mycosphaerella fijiensis in Brazil analyzed using an ERIC-PCR marker.

The Enterobacterial repetitive intergenic consensus (ERIC) marker was used to analyze the genetic variability of Mycosphaerella fijiensis, the causative agent of Black Sigatoka disease in banana plants. A total of 123 isolates were used, which were divided into populations based on their original hosts and collection sites in Brazil. A total of 9 loci were amplified, 77.

Dendrimer-carbon nanotube layer-by-layer film as an efficient host matrix for electrogeneration of PtCo electrocatalysts.

In this paper we demonstrate that layer-by-layer (LbL) films of polyamidoamine (PAMAM) dendrimers and single-walled carbon nanotubes (SWCNTs) are efficient for controlling the morphology of electrogenerated cobalt (Co) and the platinum-cobalt (PtCo) alloy. While Co grew to the micrometer scale and poorly covered the ITO substrate, with the LbL matrix it was kept in the nanoscale regime and provided full substrate coverage. Pt-decorated Co nanoparticles were then generated by applying a single potential pulse in a solution containing simultaneously Co and Pt ions.

Electrogeneration of platinum nanoparticles in a matrix of dendrimer-carbon nanotubes.

Hybrid materials with enhanced properties can now be obtained by combining nanomaterials such as carbon nanotubes and metallic nanoparticles, where the main challenge is to control fabrication conditions. In this study, we demonstrate that platinum nanoparticles (PtNps) can be electrogenerated within layer-by-layer (LbL) films of polyamidoamine (PAMAM) dendrimers and single-walled carbon nanotubes (SWCNTs), which serve as stabilizing matrices. The advantages of the possible control through electrogeneration were demonstrated with a homogeneous distribution of PtNps over the entire surface of the PAMAM/SWCNT LbL films, whose electroactive sites could be mapped using magnetic force microscopy.