Stability of crude ligninases: Effect of different hydrogen peroxide concentrations in the presence of aromatic alcohols

Summary In absence of veratryl alcohol (VA),Phanerochaete chrysosporium ligninases were extensively inactivated by H₂O₂ concentrations as low as 5.0 μM (1 hr exposure time, pH 4.5, 38°C). In the presence of 2.5 mM VA (but not 2.5 mM benzyl alcohol), protection occurred below 500 μM H₂O₂.     

A painful journey to antivenom: The therapeutic itinerary of snakebite patients in the Brazilian Amazon (The QUALISnake Study)

Access to antivenoms is not guarranteed for vulnerable populations that inhabit remote areas in the Amazon. The study of therapeutic itineraries (TI) for treatment of snakebites would support strategies to provide timely access to users. A TI is the set of processes by which individuals adhere to certain forms of treatment, and includes the path traveled in the search for healthcare, and practices to solve their health problems. This study aims to describe TIs of snakebite patients in the Brazilian Amazon. This study was carried out at the Fundação de Medicina Tropical Doutor Heitor Vieira Dourado, in Manaus, state of Amazonas, Brazil. The itinerary from the moment of the bite to the patient’s admission to the reference unit was analyzed. Sample size was defined by saturation. After an exploratory survey to collect epidemiological variables, in-depth interviews were conducted following a semi-structured guide. Patients originated from rural areas of 11 different municipalities, including ones located >500 kilometers from Manaus. A great fragmentation was observed in the itineraries, marked by several changes of means of transport along the route. Four themes emerged from the analysis: exposure to snakebite during day-to-day activities, use of traditional therapeutic practices, and personal perception of the severity, as well as the route taken and its contingencies. Access to healthcare requires considerable effort on the part of snakebite patients. Major barriers were identified, such as the low number of hospitals that offer antivenom treatment, poor access to healthcare due to long distances and geographic barriers, low acceptability of healthcare offered in countryside, lack of use of personal protective equipment, common use of ineffective or deleterious self-care practices, late recognition of serious clinical signs and resistance to seeking medical assistance. Health education, promotion of immediate transport to health centers and decentralization of antivenom from reference hospitals to community healthcare centers in the Brazilian Amazon are more effective strategies that would to maximize access to antivenom treatment.     

Original Equipment Manufacturers’ Participation in Take‐Back Initiatives in Brazil

Lax legislation and increasing demand for electronics are driving relentless growth in electronic waste (e‐waste) in the developing world. To reduce the damage caused by e‐waste and recover value from end‐of‐life (EoL) electronics, original equipment manufacturers (OEMs) have created, over the past decades, programs to divert e‐waste from landfills to recycling and reuse. Although the subject of intense debate, little is known about such initiatives in terms of levels of participation by OEMs or the extent to which they have succeeded in reducing e‐waste in developing economies. To broaden our understanding of these issues, we investigate take‐back initiatives in the thriving market of personal computers (i.e., desktop and laptop computers) in Brazil. Using a multimethod approach (electronic archival data collection and semistructured interviews with manufacturers), we find evidence that large multinational manufacturers are at the forefront of take‐back programs. However, these initiatives in many ways lag behind those implemented in the United States, a more developed market as far as product take‐back is concerned. We find the main reasons for the low levels of participation by OEMs in take‐back programs to be high collection costs, low residual values, and lax, unclear, and conflicting legislation. Moreover, we propose new avenues of research, in light of our scant knowledge of country‐specific, company‐specific, and product‐specific determinants that moderate participation.     

Regionalized phosphorus fate factors for freshwater eutrophication in Bahia,Brazil: an analysis of spatial and temporal variability

The International Journal of Life Cycle Assessment - Fate factors, for freshwater eutrophication, represent the route of a limiting-nutrient, phosphorus or nitrogen, and their degradation in the...     

Cellular localization of androgen synthesis in equine granulosa-theca cell tumors: Immunohistochemical expression of 17α-hydroxylase/17,20-lyase cytochrome P450

Elevated blood testosterone concentrations, often accompanied by male-typical behaviors, is a common signalment of mares with granulosa-theca cell tumors (GCTCs), but no definitive information exists regarding the cellular differentiation of tumors associated with androgen secretion. This study was conducted to localize and thereby define the cellular expression of 17α-hydroxylase/17,20-lyase cytochrome P450 (P450c17), the enzyme most directly responsible for androgen synthesis, in 30 GTCTs and control tissues (gonads and adrenal glands) using immuno-histochemistry (IHC). Immuno-reactivity for P450c17 was evident in approximately half of 30 specimens examined, was most consistent in the interstitial cells surrounding existing or developing cysts, and was less intense in cells within cysts in the smaller proportion of specimens where this was observed. In control tissues, the expression of P450c17 was localized primarily in theca interna of normal ovarian follicles, in theca-lutein cells of some corpora lutea, but not in granulosa-lutein cells. Testicular interstitial cells and islands of adreno-cortical cells located in the adrenal medulla of the adrenal cortex further established the specificity of the antisera used. These data provided the first substantive evidence that polyhedral cells identified previously in GTCTs by histopathology have the potential to synthesize and secrete androgens, similar to theca interna and theca lutein cells in normal equine ovaries.     

Mitochondrial GPX1 silencing triggers differential photosynthesis impairment in response to salinity in rice plants

The physiological role of plant mitochondrial glutathione peroxidases is scarcely known. This study attempted to elucidate the role of a rice mitochondrial isoform(GPX1) in photosynthesis under normal growth and salinity conditions. GPX1 knockdown rice lines(GPX1s) were tested in absence and presence of 100 mM NaCl for 6 d.Growth reduction of GPX1 s line under non-stressful conditions, compared with non-transformed(NT) plants occurred in parallel to increased H_2O_2 and decreased GSH contents. These changes occurred concurrently with photosynthesis impairment, particularly in Calvin cycle's reactions, since photochemical efficiency did not change.Thus, GPX1 silencing and downstream molecular/metabolic changes modulated photosynthesis differentially. In contrast, salinity induced reduction in both phases of photosynthesis, which were more impaired in silenced plants.These changes were associated with root morphology alterations but not shoot growth. Both studied lines displayed increased GPX activity but H_2O_2 content did not change in response to salinity. Transformed plants exhibited lower photorespiration, water use efficiency and root growth, indicating that GPX1 could be important to salt tolerance. Growth reduction of GPX1 s line might be related to photosynthesis impairment, which in turn could have involved a cross talk mechanism between mitochondria and chloroplast originated from redox changes due to GPX1 deficiency.     

Exome analysis and functional classification of identified variants in racing Quarter Horses

The main objectives of this study were to identify and functionally classify SNPs and indels by exome sequencing of animals of the racing line of Quarter Horses. Based on the individual genomic estimated breeding values (GEBVs) for maximum speed index (SImax) obtained for 349 animals, two groups of 20 extreme animals were formed. Of these individuals, 20 animals with high GEBVs for SImax and 19 with low GEBVs for SImax had their exons and 5′ and 3′ UTRs sequenced. Considering SNPs and indels, 105 182 variants were identified in the expressed regions of the Quarter Horse genome. Of these, 72 166 variants were already known and 33 016 are new variants and were deposited in a database. The analysis of the set of gene variants significantly related (P_adjusted < 0.05) to extreme animals in conjunction with the predicted impact of the changes and the physiological role of protein product pointed to two candidate genes potentially related to racing performance: SLC3A1 on ECA15 and CCN6 on ECA10.