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921.
In the present study, a semiquinone glucoside derivative (SQGD) isolated from a radioresistant bacterium Bacillus sp. INM-1 was evaluated for its immunostimulatory activities. Human peripheral blood mononuclear cells (PBMCs) were stimulated by different doses (30–90 μg/ml) of SQGD for different time (3–12 h) intervals at 37 °C, and IL-12p40, IL-23p19, IL-10, RelA and c-Jun gene expression analysis was carried out by qRT-PCR method. SQGD dose dependent cytokines protein expression kinetic analysis was carried out using western blotting. As the results of SQGD (30 μg/ml) stimulation for 3 h at 37 °C, significant induction in IL-12p40, IL-23p19 and RelA gene expression was observed in PBMCs compared to unstimulated control cells. However, no such induction in IL-10 and c-Jun gene expression was observed. Time dependent protein expression study indicated significant increase in IL-12p40, IL-12p35, IL-23p19 and RelA protein expression at 3–6 h, which was found decrease at 12 h upon SQGD treatment. In contrast, IL-10 protein expression was found to enhance significantly at 12 h after SQGD treatment to the PBMCs. SQGD dose dependent study showed approximately similar level of induction in IL-12p40, IL-12p35, IL-23p19 and RelA proteins expression at all tested concentration (30–90 μg/ml) compared to control. However, no significant change in the IL-10 and c-Jun protein expression was observed at any SQGD concentration. SQGD treatment (0.25 mg/kg b wt.) was also found to enhance anti-keyhole Limpet Hemocynin (KLH) IgM antibodies significantly in the mice immunized by KLH.Thus, SQGD fraction stimulates cellular immunity by inducing immunostimulatory cytokines and humoral immunity by enhancing IgM antibodies and could be a promising immunostimulant. Further studies related to molecular mechanisms offering immunostimulation is underway, will certainly helpful to unravel its mode of action in the biological system.  相似文献   
922.
Sahu  K. K.  Doshi  A.  Mishra  A. K.  Kranis  M. 《Netherlands heart journal》2020,28(3):171-171
Netherlands Heart Journal -  相似文献   
923.
International Journal of Peptide Research and Therapeutics - Peptides test drug 1, 2, 3 and 4 coded as RK, KH, RRH, and RRK were subjected to in-vitro antioxidant screening methods for the...  相似文献   
924.
The prevalence of non-alcoholic fatty-liver disease (NAFLD) is increasing globally. NAFLD is a spectrum of related liver diseases that progressive from simple steatosis to serious complications like cirrhosis. The major pathophysiological driving of NAFLD includes elevated hepatic adiposity, increased hepatic triglycerides/cholesterol, excessive hepatic inflammation, and hepatocyte ballooning injury is a common histo-pathological denominator. Although heme-oxygenase (HO) is cytoprotective, its effects on hepatocyte ballooning injury have not been reported. We investigated the effects of upregulating HO with hemin or inhibiting it with stannous-mesoporphyrin (SnMP) on hepatocyte ballooning injury, hepatic adiposity and inflammation in Zucker-diabetic-fatty rats (ZDFs), an obese type-2-diabetic model. Hemin administration to ZDFs abated hepatic/plasma triglycerides and cholesterol, and suppressed several pro-inflammatory cytokines and chemokines including, TNF-α, IL-6, IL-1β, macrophage-inflammatory-protein-1α (MIP-1α) and macrophage-chemoattractant-protein-1 (MCP-1), with corresponding reduction of the pro-inflammatory M1-phenotype marker, ED1 and hepatic macrophage infiltration. Correspondingly, hemin concomitantly potentiated the protein expression of several markers of the anti-inflammatory macrophage-M2-phenotype including ED2, IL-10 and CD-206, alongside components of the HO-system including HO-1, HO-activity and cGMP, whereas the HO-inhibitor, SnMP abolished the effects. Furthermore, hemin attenuated liver histo-pathological lesions like hepatocyte ballooning injury and fibrosis, and reduced extracellular-matrix/profibrotic proteins implicated in liver injury such as osteopontin, TGF-β1, fibronectin and collagen-IV. We conclude that hemin restore hepatic morphology by abating hepatic adiposity, suppressing macrophage infiltration, inflammation and fibrosis. The selective enhancement of anti-inflammatory macrophage-M2-phenotype with parallel reduction of pro-inflammatory macrophage-M1-phenotype and related chemokines/cytokines like TNF-α, IL-6, IL-1β, MIP-1α and MCP-1 are among the multifaceted mechanisms by which hemin restore hepatic morphology.  相似文献   
925.
Brevibacillus massiliensis strain phRT sp. nov. is the type strain of B. massiliensis sp. nov., a new species within the genus Brevibacillus. This strain was isolated from the fecal flora of a woman suffering from morbid obesity. B. massiliensis is a Gram-positive aerobic rod-shaped bacterium. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 5,051,018 bp long genome (1 chromosome but no plasmid) contains 5,051 protein-coding and 84 RNA genes, and exhibits a G+C content of 53.1%.  相似文献   
926.
The human dopamine D2 receptor long isoform (D2L) has significant implications in neurological and neuropsychiatric disorders such as Parkinson's disease and schizophrenia. Detailed structural knowledge of this receptor is limited owing to its highly hydrophobic nature, which leads to protein aggregation and host toxicity when expressed in cellular systems. The newly emerging field of cell‐free protein expression presents numerous advantages to overcome these challenges. This system utilizes protein synthesis machinery and exogenous DNA to synthesize functional proteins outside of intact cells. This study utilizes two different cell‐free systems for the synthesis of human dopamine D2L receptor. These include the Escherichia coli lysate‐based system and the wheat‐germ lysate‐based system. The bacterial cell‐free method used pET 100/D‐TOPO vector to synthesize hexa‐histidine‐tagged D2L receptor using a dialysis bag system; the resulting protein was purified using nickel‐nitrilotriacetic acid affinity resin. The wheat germ system used pEU–glutathione‐S‐transferase (GST) vector to synthesize GST‐tagged D2L receptor using a bilayer translation method; the resulting protein was purified using a GST affinity resin. The presence and binding capacity of the synthesized D2L receptor was confirmed by immunoblotting and radioligand competition assays, respectively. Additionally, in‐gel protein sequencing via Nano LC‐MS/MS was used to confirm protein synthesis via the wheat germ system. The results showed both systems to synthesize microgram quantities of the receptor. Improved expression of this highly challenging protein can improve research and understanding of the human dopamine D2L receptor. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:601–608, 2013  相似文献   
927.
Under natural conditions, plants have to cope with numerous stresses, including light-stress and herbivory. This raises intriguing questions regarding possible trade-offs between stress defences and growth. As part of a program designed to address these questions we have compared herbivory defences and damage in wild type Arabidopsis thaliana and two “photoprotection genotypes”, npq4 and oePsbS, which respectively lack and overexpress PsbS (a protein that plays a key role in qE-type non-photochemical quenching). In dual-choice feeding experiments both a specialist (Plutella xylostella) and a generalist (Spodoptera littoralis) insect herbivore preferred plants that expressed PsbS most strongly. In contrast, although both herbivores survived equally well on each of the genotypes, for oviposition female P. xylostella adults preferred plants that expressed PsbS least strongly. However, there were no significant differences between the genotypes in levels of the 10 most prominent glucosinolates; key substances in the Arabidopsis anti-herbivore chemical defence arsenal. After transfer from a growth chamber to the field we detected significant differences in the genotypes’ metabolomic profiles at all tested time points, using GC-MS, but no consistent “metabolic signature” for the lack of PsbS. These findings suggest that the observed differences in herbivore preferences were due to differences in the primary metabolism of the plants rather than their contents of typical “defence compounds”. A potentially significant factor is that superoxide accumulated most rapidly and to the highest levels under high light conditions in npq4 mutants. This could trigger changes in planta that are sensed by herbivores either directly or indirectly, following its dismutation to H2O2.  相似文献   
928.
We extend the continuity of microblade technology in the Indian Subcontinent to 45 ka, on the basis of optical dating of microblade assemblages from the site of Mehtakheri, (22° 13'' 44″ N Lat 76° 01'' 36″ E Long) in Madhya Pradesh, India. Microblade technology in the Indian Subcontinent is continuously present from its first appearance until the Iron Age (~3 ka), making its association with modern humans undisputed. It has been suggested that microblade technology in the Indian Subcontinent was developed locally by modern humans after 35 ka. The dates reported here from Mehtakheri show this inference to be untenable and suggest alternatively that this technology arrived in the Indian Subcontinent with the earliest modern humans. It also shows that modern humans in Indian Subcontinent and SE Asia were associated with differing technologies and this calls into question the “southern dispersal” route of modern humans from Africa through India to SE Asia and then to Australia. We suggest that modern humans dispersed from Africa in two stages coinciding with the warmer interglacial conditions of MIS 5 and MIS 3. Competitive interactions between African modern humans and Indian archaics who shared an adaptation to tropical environments differed from that between modern humans and archaics like Neanderthals and Denisovans, who were adapted to temperate environments. Thus, while modern humans expanded into temperate regions during warmer climates, their expansion into tropical regions, like the Indian Subcontinent, in competition with similarly adapted populations, occurred during arid climates. Thus modern humans probably entered the Indian Subcontinent during the arid climate of MIS 4 coinciding with their disappearance from the Middle East and Northern Africa. The out of phase expansion of modern humans into tropical versus temperate regions has been one of the factors affecting the dispersal of modern humans from Africa during the period 200–40 ka.  相似文献   
929.
Epigenetic cellular memory mechanisms that involve polycomb and trithorax group of proteins are well conserved across metazoans. The cis-acting elements interacting with these proteins, however, are poorly understood in mammals. In a directed search we identified a potential polycomb responsive element with 25 repeats of YY1 binding motifthatwe designate PRE-PIK3C2B as it occurs in the first intron of human PIK3C2B gene. It down regulates reporter gene expression in HEK cells and the repression is dependent on polycomb group of proteins (PcG). We demonstrate that PRE-PIK3C2B interacts directly with YY1 in vitro and recruits PRC2 complex in vivo. The localization of PcG proteins including YY1 to PRE-PIK3C2B in HEK cells is decreased on knock-down of either YY1 or SUZ12. Endogenous PRE-PIK3C2B shows bivalent marking having H3K27me3 and H3K4me3 for repressed and active state respectively. In transgenic Drosophila, PRE-PIK3C2B down regulates mini-white expression, exhibits variegation and pairing sensitive silencing (PSS), which has not been previously demonstrated for mammalian PRE. Taken together, our results strongly suggest that PRE-PIK3C2B functions as a site of interaction for polycomb proteins.  相似文献   
930.
Several deleterious intra-acinar phenomena are simultaneously triggered on initiating acute pancreatitis. These culminate in acinar injury or inflammatory mediator generation in vitro and parenchymal damage in vivo. Supraphysiologic caerulein is one such initiator which simultaneously activates numerous signaling pathways including non-receptor tyrosine kinases such as of the Src family. It also causes a sustained increase in cytosolic calcium- a player thought to be crucial in regulating deleterious phenomena. We have shown Src to be involved in caerulein induced actin remodeling, and caerulein induced changes in the Golgi and post-Golgi trafficking to be involved in trypsinogen activation, which initiates acinar cell injury. However, it remains unclear whether an increase in cytosolic calcium is necessary to initiate acinar injury or if injury can be initiated at basal cytosolic calcium levels by an alternate pathway. To study the interplay between tyrosine kinase signaling and calcium, we treated mouse pancreatic acinar cells with the tyrosine phosphatase inhibitor pervanadate. We studied the effect of the clinically used Src inhibitor Dasatinib (BMS-354825) on pervanadate or caerulein induced changes in Src activation, trypsinogen activation, cell injury, upstream cytosolic calcium, actin and Golgi morphology. Pervanadate, like supraphysiologic caerulein, induced Src activation, redistribution of the F-actin from its normal location in the sub-apical area to the basolateral areas, and caused antegrade fragmentation of the Golgi. These changes, like those induced by supraphysiologic caerulein, were associated with trypsinogen activation and acinar injury, all of which were prevented by Dasatinib. Interestingly, however, pervanadate did not cause an increase in cytosolic calcium, and the caerulein induced increase in cytosolic calcium was not affected by Dasatinib. These findings suggest that intra-acinar deleterious phenomena may be initiated independent of an increase in cytosolic calcium. Other players resulting in acinar injury along with the Src family of tyrosine kinases remain to be explored.  相似文献   
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