Mind-altering with the gut: Modulation of the gut-brain axis with probiotics

It is increasingly evident that bidirectional interactions exist among the gastrointestinal tract, the enteric nervous system, and the central nervous system. Recent preclinical and clinical trials have shown that gut microbiota plays an important role in these gut-brain interactions. Furthermore, alterations in gut microbiota composition may be associated with pathogenesis of various neurological disorders, including stress, autism, depression, Parkinson’s disease, and Alzheimer’s disease. Therefore, the concepts of the microbiota-gut-brain axis is emerging. Here, we review the role of gut microbiota in bidirectional interactions between the gut and the brain, including neural, immune-mediated, and metabolic mechanisms. We highlight recent advances in the understanding of probiotic modulation of neurological and neuropsychiatric disorders via the gut-brain axis.     

Microorganisms associated with the retting of flax treated with the herbicide glyphosate

Greater numbers of fungi were isolated from stems of flax following treatment with the herbicide glyphosate than from untreated stems although there was also a general increase in numbers with time. The fungal genera isolated were the same from both treated and untreated plants, the most common being Cladosporium, Aureobasidium, Epicoccum and Botrytis with Cladosporium being predominant. Populations of bacteria were generally not enhanced after glyphosate treatment. Partial dew-retting of crops resulted in the reduction in numbers of Cladosporium compared with conventionally-treated flax. The increase in numbers of fungi was associated with an increase in retting. Overretting also occurred, particularly in discrete pale areas on the stem. These were associated with colonisation by Botrytis cinerea and the tensile strength of fibres from these areas was 15 times weaker than from surrounding darker areas of the stem. Light microscopy showed death of cells after glyphosate application, followed by invasion and degradation of the epidermis and cortex by fungi and other microorganisms. Fibre bundles were partially dissociated but the individual fibres remained largely intact as did the xylem and medulla.     

生物素标记寡核苷酸探针检测B群轮状病毒

用５′端接氨基标记法,用生物素对Ｂ群轮状病毒（ＧＢＲＶ）ＩＤＩＲ株具有群特异性的３片段基因上２３ｂｐ寡核苷酸序列进行标记,经高效薄层层析板（ＨＰＴＬＣ）纯化,制备了Ｂ群轮状病毒生物素寡核苷酸探针,探针显色灵敏度达１０Ｐｇ,与ＧＢＲＶ、ＫＢ６３株基因杂交可检测到１００ｐｇ靶序列,而与Ａ群和Ｃ群轮状病毒及无关基因均不产生杂交信号,该探针可用于Ｂ群轮状病毒的检测、鉴定,以及同群不同毒株间基因相关性研究。     

Hunting with Polar Bears: Problems with the Passive Properties of the Commons

Inuit in Canada’s Arctic conceptualize both human hunters and their polar bear prey as active participants in the hunt and as part of a larger socio-economic system requiring the involvement of both humans and animals. Although often treated through the lens of common-pool resource theory, the Inuit viewpoint conflicts with Western wildlife management systems that typically treat animals, and nature in general, as passive. When polar bears are understood as active participants in the hunt, the rights associated with common property regimes and assumptions about collective-choice decisions in common-pool resource management require significant revision. In this paper we argue that common-pool resource theories which assume natural resources are inherently passive cannot adequately account for the system of active relationships operating among Inuit in Arctic Canada. The co-management system of Nunavut Territory, Canada, uses a flexible quota approach, which, while following conservation guidelines, allows some space for the traditional Inuit-polar bear system to operate. This example shows how common-pool resources may be managed sustainably without the attendant assumption that natural resources exist passively outside of common-pool resource regimes.     

Regeneration of the acorn worm pygochord with the implication for its convergent evolution with the notochord

The origin of the notochord is a central issue in chordate evolution. This study examined the development of the acorn worm pygochord, a putative homologue of the notochord. Because the pygochord differentiates only after metamorphosis, the developmental was followed process by inducing regeneration after artificial amputation in Ptychodera flava. It was found that although the regeneration of the posterior part of the body did not proceed via formation of an obvious regeneration bud, pygochord regeneration was observed within a few weeks, possibly via trans-differentiation of endoderm cells. The expression of the fibrillary collagen gene (Fcol) and elav in the pygochord during regeneration was detected. This indicates that pygochord cells are not part of gut epithelial cells, but that they differentiated as a distinct cell type. Our gene expression analyses do not provide supporting evidence for the homology between the pygochord and notochord, but rather favored the convergent evolution between them.     

Advancement in the derivatizations of the amino groups with the o-phthaldehyde-thiol and with the 9-fluorenylmethyloxycarbonyl chloride reagents

An overview is presented on the advancement of the two most frequently used derivatization protocols applying the o-phthalaldehyde (OPA)-thiol and the fluorenylmethyloxycarbonyl (FMOC) chloride reagents, prior to the high performance liquid chromatographic analysis of amino acids. This review pays special attention (i) to the blank value, to the composition, to the stability and to the life time of the reagents, (ii) to the optimum pH conditions for the interactions and derivatives' elutions, (iii) to the characteristics and behavior of those amino acids which might provide more than one derivative correlating with the molar ratios of the reagent to the reactants, and (iv) on the practical applicability of the optimized protocols.     

Modification of albumin with different degrees of the oxidation of SH-groups in the reaction with glucose

A molecule of the major blood protein albumin contains 34 cysteine residues involved in disulfide bonds and one unpaired SH-group of residue Cys34. Normally, 20–30% of these SH-groups are oxidized and form disulfide bonds or the derivatives of sulfenic, sulfinic, and sulfonic acids. The goal of the present work was to study the influence of the degree of oxidation of sulfhydryl groups on the capacity of albumin for glycation. Commercially available human albumin containing 0.4 moles of sulfhydryl groups per 1 mole of the protein (nonmercaptalbumin) was used. Disulfide bonds in this preparation were reduced with dithiothreitol to 0.7 mole/mole to give mercaptalbumin. The preparations were incubated for three weeks with glucose at a concentration of 5 and 50 mM. The content of ketoamine, a glycation product, was determined by the colorimetric method, the content of pentosidine (glycation end product) was analyzed by fluorescence, and the content of SH-groups was determined using the Ellman’s reagent. Changes in the structure and properties of the protein during glycation were studied by fluorescence and HPLC. During the incubation of both albumin preparations with 5 mM glucose, no significant increase in the ketoamine content was observed, whereas the incubation with 50 mM glucose was accompanied by a considerable accumulation of ketoamine. It was found that the greatest amount of ketoamine under these conditions forms in nonmercaptalbumin; in this case, the intensity of tryptophan fluorescence decreases. The intensity of pentosidine fluorescence increases with increasing content of ketoamine. The results obtained enable the conclusion that the oxidation of free SH-groups of the protein changes its conformation; as a result, the glycation of earlier hidden sites becomes possible, and the degree of protein glycation increases.     

Condensin goes with the family but not with the flow

Condensin and cohesin are loaded onto yeast chromosomes by a common mechanism at RNA polymerase III transcribed genes. Whereas cohesin translocates from these loading sites to mediate cohesion at secondary locations, condensin remains, bringing distant sites together into clusters.