Abstract
Plastic degradation by biological systems with re-utilization of the by-products could be a future solution to the global threat of plastic waste accumulation. Here, we report that the ...saliva of
Galleria mellonella
larvae (wax worms) is capable of oxidizing and depolymerizing polyethylene (PE), one of the most produced and sturdy polyolefin-derived plastics. This effect is achieved after a few hours’ exposure at room temperature under physiological conditions (neutral pH). The wax worm saliva can overcome the bottleneck step in PE biodegradation, namely the initial oxidation step. Within the saliva, we identify two enzymes, belonging to the phenol oxidase family, that can reproduce the same effect. To the best of our knowledge, these enzymes are the first animal enzymes with this capability, opening the way to potential solutions for plastic waste management through bio-recycling/up-cycling.
Objectives
The objective of this study was to compare waveforms obtained with a new device for the non‐invasive monitoring of intracranial pressure (ICP) in dogs with and without neurological ...disease.
Materials and Methods
This prospective study was conducted on both neurologically normal dogs and dogs with neurological diseases. First, non‐invasive ICP waveforms were recorded in normal dogs using the Braincare® BcMM 2000 monitor while the dogs were under general anaesthesia induced for procedures unrelated to this study. The dogs were positioned in lateral recumbency, and the sensor was placed over the skin of the parietal region. Secondly, non‐invasive ICP waveforms were monitored in dogs with brain and spinal disease until waveforms with characteristic peaks were acquired. All the recorded signals were amplified, filtered and digitalized, by the device, and then transferred to a computer for analysis.
Results
Normal pulse waveforms indicating normal brain complacency were observed in eight neurologically normal dogs. In six dogs with brain disease, abnormal pulse waveforms were observed suggesting increased ICP and decreased brain complacency. Four dogs with spinal disease undergoing myelography, had normal waveforms before contrast medium injection and abnormal pulse waveforms during contrast medium injection, indicating a potential increase in ICP.
Clinical Significance
Based on these preliminary observations, this method was capable of detecting abnormal pulse waveforms that suggested increased ICP.
Objectives
The objective of this study was to evaluate the ability of
Lactobacillus curvatus
CRL705, CRL1532, and CRL1533 and
Lactobacillus sakei
CRL1613 to survive under simulated gastrointestinal ...conditions. Moreover, a microencapsulation approach was proposed to improve gastrointestinal survival. Finally, experiments were performed to demonstrate that
Lactobacill
us spp. can modulate the ability of
Listeria monocytogenes
FBUNT to adhere to and invade Caco-2 cells.
Results
Lactobacillus
strains were encapsulated in alginate beads to enhance the survival of bacteria under in vitro gastrointestinal conditions. All strains hydrolyzed bile salts using chenodeoxycholic acid as a substrate and adhered to Caco-2 cells. Cell-free supernatants (CFSs) showed antimicrobial activity against
L. monocytogenes
as demonstrated by agar diffusion assays. The average percentages of
L. monocytogenes
adhesion decreased from 67.74 to 41.75 and 38.7% in the presence of 50 and 90% (v/v), respectively, for all CFSs tested. The highest concentrations of CFSs completely inhibited the
L. monocytogenes
invasion of Caco-2 cells.
Conclusions
The studied
Lactobacillus
strains have protective effects against the adhesion and invasion of
L. monocytogenes
FBUNT. Alginate encapsulation of these bacteria improved gastrointestinal tolerance such that they could be further studied as potential probiotics against intestinal pathogenic bacteria.
Among etiologic agents, rotavirus is the major cause of severe dehydration diarrhea in infant mammals. In vitro and in vivo studies have indicated that the human milk-fat globule protein lactadherin ...inhibits rotavirus binding and protects breast-fed children against symptomatic rotavirus infection. The present work was conducted to evaluate the effect of lactadherin, along with some other milk proteins and fractions, on rotavirus infections in MA104 and Caco-2 cell lines. It is shown that human, and not bovine, lactadherin inhibits Wa rotavirus infection in vitro. Human lactadherin seems to act through a mechanism involving protein-virus interactions. The reason for the activity of human lactadherin is not clear, but it might lie within differences in the protein structure or the attached oligosaccharides. Likewise, in our hands, bovine lactoferrin did not show any suppressive activity against rotavirus. In contrast, MUC1 from bovine milk inhibits the neuraminidase-sensitive rotavirus RRV strain efficiently, whereas it has no effect on the neuraminidase-resistant Wa strain. Finally, a bovine macromolecular whey protein fraction turned out to have an efficient and versatile inhibitory activity against rotavirus.
Different carbon materials were tested as precursors for the production of
C
O2
adsorbents. The chemical modification of the surface of the prepared adsorbents was studied by means of three different ...approaches: impregnation with amines, electrophilic aromatic substitution, and heat treatment in the presence of ammonia. The samples were chemically characterized and the porous texture was evaluated from the
N2
adsorption isotherms at
−196°C
. The
C
O2
adsorption capacities of the adsorbents at 25 and
100°C
were evaluated in a thermogravimetric analyzer. In general, the incorporation of basic nitrogen functionalities enhanced the
C
O2
capture capacities of the modified carbons, but this increase depended on the textural properties of the support and the surface modification methodology.
C
O2
adsorption capacities of up to
111
mg
C
O2
∕g
at room temperature were attained. All the tested samples were completely regenerated when subjected to heat treatment at
100°C
under inert atmosphere.
Rotavirus entry into a cell is a complex multistep process in which different domains of the rotavirus surface proteins interact with different cell surface molecules, which act as attachment and ...entry receptors. These recently described molecules include several integrins and a heat shock protein, which have been found to be associated with cell membrane lipid microdomains. The requirement during viral entry for several cell molecules, which might be required to be present and organized in a precise fashion, could explain the selective cell and tissue tropism of these viruses. This review focuses on recent data describing the virus–receptor interactions, the role of lipid microdomains in rotavirus infection and the mechanism of rotavirus cell entry.
BACKGROUND: In Brazil, dengue epidemics erupt sporadically throughout the country and it is unclear if outbreaks may initiate a sustainable transmission cycle. There are few studies evaluating the ...ability of Brazilian Aedes aegypti populations to transmit dengue virus (DENV). The aim of this study was to compare DENV susceptibility of field-captured Ae. aegypti populations from nine distinct geographic areas of the city of Belo Horizonte in 2009 and 2011. Infection Rate (IR), Vector Competence (VC) and Disseminated Infection Rate (DIR) were determined. METHODS: Aedes aegypti eggs from each region were collected and reared separately in an insectary. Adult females were experimentally infected with DENV-2 and the virus was detected by qPCR in body and head samples. Data were analyzed with the Statistical Package for the Social Sciences version 17. RESULTS: IR varied from 40.0% to 82.5% in 2009 and 60.0% to 100.0% in 2011. VC ranged from 25.0% to 77.5% in 2009 and 25.0% to 80.0% in 2011. DIR oscillated from 68.7% to 100.0% in 2009 and 38.4% to 86.8 in 2011. When the results were evaluated by a logistic model using IR as covariate, North, Barreiro, South-Central and Venda Nova showed the strongest association in 2009. In 2011, a similar association was observed for South-Central, Venda Nova, West and Northeast regions. Using VC as covariate, South-Central and Venda Nova showed the most relevant association in 2009. In 2011, South-Central, Venda Nova and Barreiro presented the greatest revelation associations. When DIR data were analyzed by logistic regression models, Pampulha, South-Central, Venda Nova, West, Northeast and East (2009) as well as South-Central, Venda Nova and West (2011) were the districts showing the strongest associations. CONCLUSIONS: We conclude that Ae. aegypti populations from Belo Horizonte exhibit wide variation in vector competence to transmit dengue. Therefore, vector control strategies should be adapted to the available data for each region. Further analysis should be conducted to better understand the reasons for this large variability in vector competence and how these parameters correlate with epidemiological findings in subsequent years.
To provide a comprehensive overview of geographical patterns (2001-2010) and time trends (1993-2012) of cancer incidence in children aged 0-19 years in Latin America and the Caribbean (LAC) and ...interpret the findings in the context of global patterns.
Geographical variations in 2001-2010 and incidence trends over 1993-2012 in the population of LAC younger than 20 years were described using the database of the third volume of the International Incidence of Childhood Cancer study containing comparable data. Age-specific incidence per million person-years (ASR) was calculated for population subgroups and age-standardized (WSR) using the world standard population.
Overall, 36 744 unique cases were included in this study. In 2001-2010 the overall WSR in age 0-14 years was 132.6. The most frequent were leukemia (WSR 48.7), central nervous system neoplasms (WSR 23.0), and lymphoma (WSR 16.6). The overall ASR in age group 15-19 years was 152.3 with lymphoma ranking first (ASR 30.2). Incidence was higher in males than in females, and higher in South America than in Central America and the Caribbean. Compared with global data LAC incidence was lower overall, except for leukemia and lymphoma at age 0-14 years and the other and unspecified tumors at any age. Overall incidence at age 0-19 years increased by 1.0% per year (95% CI 0.6, 1.3) over 1993-2012. The included registries covered 16% of population aged 0-14 years and 10% of population aged 15-19 years.
The observed patterns provide a baseline to assess the status and evolution of childhood cancer occurrence in the region. Extended and sustained support of cancer registration is required to improve representativeness and timeliness of data for childhood cancer control in LAC.
Chagas cardiomyopathy, caused by Trypanosoma cruzi infection, continues to be a neglected illness, and has a major impact on global health. The parasite undergoes several stages of morphological and ...biochemical changes during its life cycle, and utilizes an elaborated antioxidant network to overcome the oxidants barrier and establish infection in vector and mammalian hosts. Trypanothione synthetase (TryS) catalyzes the biosynthesis of glutathione-spermidine adduct trypanothione (T(SH)2) that is the principal intracellular thiol-redox metabolite in trypanosomatids.
We utilized genetic overexpression (TryShi) and pharmacological inhibition approaches to examine the role of TryS in T. cruzi proliferation, tolerance to oxidative stress and resistance to anti-protozoal drugs. Our data showed the expression and activity of TryS was increased in all morphological stages of TryShi (vs. control) parasites. In comparison to controls, the TryShi epimastigotes (insect stage) recorded shorter doubling time, and both epimastigotes and infective trypomastigotes of TryShi exhibited 36–71% higher resistance to H2O2 (50–1000 μM) and heavy metal (1–500 μM) toxicity. Treatment with TryS inhibitors (5–30 μM) abolished the proliferation and survival advantages against H2O2 pressure in a dose-dependent manner in both TryShi and control parasites. Further, epimastigote and trypomastigote forms of TryShi (vs. control) T. cruzi tolerated higher doses of benznidazole and nifurtimox, the drugs currently administered for acute Chagas disease treatment.
TryS is essential for proliferation and survival of T. cruzi under normal and oxidant stress conditions, and provides an advantage to the parasite to develop resistance against currently used anti-trypanosomal drugs. TryS indispensability has been chemically validated with inhibitors that may be useful for drug combination therapy against Chagas disease.
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•Trypanothione synthetase (TryS) is an essential enzyme for T. cruzi.•TryS-overexpression confers higher replication rate to T. cruzi epimastigotes.•TryS provides protection against oxidative stress to different parasite stages.•TryS confers resistance to current treatment drugs, benznidazole and nifurtimox.
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