Comparison of Cell Wall Polysaccharide Hydrolysis by a Dilute Acid/Enzymatic Saccharification Process and Rumen Microorganisms

Evaluation of biomass crops for breeding or pricing purposes requires an assay that predicts performance in the bioenergy conversion process. Cell wall polysaccharide hydrolysis was compared for a dilute sulfuric acid pretreatment at 121°C followed with cellulase hydrolysis for 72?h conversion assay (CONV) with in vitro rumen microflora incubation for 72?h (RUMEN) for a set of maize (Zea mays L.) stover samples with a wide range in cell wall composition. Residual polysaccharides from the assays were analyzed for sugar components and extent of hydrolysis calculated. Cell wall polysaccharide hydrolysis was different for all sugar components between the CONV and RUMEN assays. The CONV assay hydrolyzed xylose-, arabinose-, galactose-, and uronic acid-containing polysaccharides to a greater degree than did the RUMEN assay, whereas the RUMEN assay was more effective at hydrolyzing glucose- and mannose-containing polysaccharides. Greater hydrolysis of hemicelluloses and pectins by CONV can be attributed to the acid hydrolysis mechanism of the CONV assay for noncellulosic polysaccharides, whereas the RUMEN assay was dependent on enzymatic hydrolysis. While CONV and RUMEN hydrolysis were correlated for most polysaccharide components, the greatest correlation was only r?=?0.70 for glucose-containing polysaccharides. Linear correlations and multiple regressions indicated that polysaccharide hydrolysis by the RUMEN assay was negatively associated with lignin concentration and ferulate ether cross linking as expected. Corresponding correlations and regressions for CONV were less consistent and occasionally positive. Use of rumen microbial hydrolysis to characterize biomass performance in a conversion process may have some limited usefulness for genetic evaluations, but such assays would be unreliable for biomass pricing.     

Protection Induced by Simultaneous Subcutaneous and Endobronchial Vaccination with BCG/BCG and BCG/Adenovirus Expressing Antigen 85A against Mycobacterium bovis in Cattle

The incidence of bovine tuberculosis (bTB) in the GB has been increasing since the 1980s. Immunisation, alongside current control measures, has been proposed as a sustainable measure to control bTB. Immunisation with Mycobacterium bovis bacillus Calmette-Guerin (BCG) has been shown to protect against bTB. Furthermore, much experimental data indicates that pulmonary local immunity is important for protection against respiratory infections including Mycobacterium tuberculosis and that pulmonary immunisation is highly effective. Here, we evaluated protection against M. bovis, the main causative agent of bTB, conferred by BCG delivered subcutaneously, endobronchially or by the new strategy of simultaneous immunisation by both routes. We also tested simultaneous subcutaneous immunisation with BCG and endobronchial delivery of a recombinant type 5 adenovirus expressing mycobacterial antigen 85A. There was significantly reduced visible pathology in animals receiving the simultaneous BCG/BCG or BCG/Ad85 treatment compared to naïve controls. Furthermore, there were significantly fewer advanced microscopic granulomata in animals receiving BCG/Ad85A compared to naive controls. Thus, combining local and systemic immunisation limits the development of pathology, which in turn could decrease bTB transmission.     

AHNAK controls 53BP1-mediated p53 response by restraining 53BP1 oligomerization and phase separation

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The Protective Action of Rubus sp. Fruit Extract Against Oxidative Damage in Mice Exposed to Lipopolysaccharide

Neurochemical Research - Neuroinflammation is an event that occurs in several pathologies of brain. Rubus sp. (blackberry) is a powerful antioxidant fruit, and its extract has neuroprotective...     

Glutathione depletion switches nitric oxide neurotrophic effects to cell death in midbrain cultures: implications for Parkinson's disease

Nitric oxide (NO) exerts neurotrophic and neurotoxic effects on dopamine (DA) function in primary midbrain cultures. We investigate herein the role of glutathione (GSH) homeostasis in the neurotrophic effects of NO. Fetal midbrain cultures were pretreated with GSH synthesis inhibitor, l ‐buthionine‐(S,R)‐sulfoximine (BSO), 24 h before the addition of NO donors (diethylamine/nitric oxide‐complexed sodium and S‐nitroso‐N‐acetylpenicillamine) at doses tested previously as neurotrophic. Under these conditions, the neurotrophic effects of NO disappeared and turned on highly toxic. Reduction of GSH levels to 50% of baseline induced cell death in response to neurotrophic doses of NO. Soluble guanylate cyclase (sGC) and cyclic GMP‐dependent protein kinase (PKG) inhibitors protected from cell death for up to 10 h after NO addition; the antioxidant ascorbic acid also protected from cell death but its efficacy decreased when it was added after NO treatment (40% protection 2 h after NO addition). The pattern of cell death was characterized by an increase in chromatin condensed cells with no DNA fragmentation and with breakdown of plasmatic membrane. The inhibition of RNA and protein synthesis and of caspase activity also protected from cell death. This study shows that alterations in GSH levels change the neurotrophic effects of NO in midbrain cultures into neurotoxic. Under these conditions, NO triggers a programmed cell death with markers of both apoptosis and necrosis characterized by an early step of free radicals production followed by a late requirement for signalling on the sGC/cGMP/PKG pathway.     

Archenteron cells are responsible for the increase in ribosomal RNA synthesis in sea urchin gastrulae

Paracentrotus lividus embryos were continuously labeled with P32 from hatching blastula to pluteus. The archenteron cells were then separated from the rest of the embryo and the radioactivity accumulated into the ribosomal RNA of the two cell groups measured. The results clearly indicate that the bulk of ribosomal RNA is mainly if not entirely, synthesized in this time interval by the archenteron cells.     

Equine and Canine Anaplasma phagocytophilum Strains Isolated on the Island of Sardinia (Italy) Are Phylogenetically Related to Pathogenic Strains from the United States

The presence of Anaplasma phagocytophilum, a tick-transmitted zoonotic pathogen, was investigated in Sardinia using a molecular approach. Phylogenetic analysis revealed that Sardinian strains are genetically distinct from the two lineages previously described in Europe and are closely related to strains isolated in different areas of the United States.     

Reproductive modes and life cycles of freshwater planarians (Platyhelminthes, Tricladida, Paludicula) from southern Brazil

Abstract. Life cycles, ploidy levels, reproductive modes, and regeneration capacities of laboratory populations of the southern Brazil freshwater planarians Girardia tigrina and Girardia schubarti were studied. The mating behavior and life cycle of different populations from both species were analyzed regarding their karyotype, body size, modes of reproduction, and regeneration potential. Reproduction was evaluated according to fecundity, fertility, and fissiparity indices. In both species we observed that diploid planarians are ∼25% larger than triploid or mixoploid ones and that sexually reproducing populations have more offspring than asexual ones. Cocoon incubation time was shorter for G. tigrina , and G. schubarti showed a higher frequency of spontaneous malformations. G. tigrina was both more fecund (produced more cocoons) and more fertile (produced more hatchlings) than G. schubarti . The effects of alternative food sources (liver or egg yolk), demographic density, and water–salt concentration were evaluated in different populations of both species. All evaluated environmental factors had effects on fecundity and fertility indices and were more prominent for G. schubarti than for G. tigrina . Our data suggest that the populations of G. schubarti were more sensitive to environmental factors, and thus may be useful as bioindicators.