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181.
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In vitro activity of milk leukocytes (viz. neutrophils, lymphocytes and macrophages) was evaluated in forty-eight (48) clinically healthy high-yielding cross-bred cows of mid-lactation stage (100–200 days of lactation), divided into four groups namely 1st parity (n = 12), 2nd parity (n = 12), 3rd parity (n = 12) and 4th and above parity (n = 12). Milk samples were taken (250 ml/cow) were taken. Milk somatic cell counts (SCC) and differential leukocyte counts (DLC) were performed microscopically. In vitro phagocytic index (PI) of milk neutrophils and macrophages was evaluated by colorimetric nitro blue tetrazolium reductive assay. Mitogen-induced milk lymphocyte blastogenic response was measured by colorimetric MTT (tetrazolium) assay after isolation of the milk leukocytes by density gradient centrifugation. Milk SCC differed significantly (p < 0.01) between different parity. Cows of 4 and above parity showed significantly (p < 0.01) higher milk SCC compared to primiparous cows. There was no significant difference in milk DLC during different parities in high-yielding cross-bred cows. There was a significant (p < 0.01) variation in lymphocyte blastogenesis amongst parity. The highest value of lymphocyte blastogenesis was seen at 3rd parity, whereas lowest value was obtained in the cows of both 1st and 4th or above parity. PI of milk neutrophils did not differ significantly between parity. PI of milk macrophages was significantly (p < 0.01) higher in 3rd parity and lower (p < 0.01) in 1st and 4th parities. The study indicated that depressed activity of milk lymphocytes and macropages was lower and SCC was higher in the cows of 4th and above parity indicating more mammary stress and hence susceptible to udder infection and mastitis. Therefore, better care and managemental interventions should be taken around these periods.  相似文献   
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Introduction: Metabolomics is a chemical process, involving the characterization of metabolites and cellular metabolism. Recent studies indicate that numerous metabolic pathways are altered in bladder cancer (BLCA), providing potential targets for improved detection and possible therapeutic intervention. We review recent advances in metabolomics related to BLCA and identify various metabolites that may serve as potential biomarkers for BLCA.

Areas covered: In this review, we describe the latest advances in defining the BLCA metabolome and discuss the possible clinical utility of metabolic alterations in BLCA tissues, serum, and urine. In addition, we focus on the metabolic alterations associated with tobacco smoke and racial disparity in BLCA.

Expert commentary: Metabolomics is a powerful tool which can shed new light on BLCA development and behavior. Key metabolites may serve as possible markers of BLCA. However, prospective validation will be needed to incorporate these markers into clinical care.  相似文献   

185.
In February 2018, the Melanoma Research Foundation and the Moffitt Cancer Center hosted the Second Summit on Melanoma Central Nervous System (CNS) Metastases in Tampa, Florida. In this white paper, we outline the current status of basic science, translational, and clinical research into melanoma brain metastasis development and therapeutic management. We further outline the important challenges that remain for the field and the critical barriers that need to be overcome for continued progress to be made in this clinically difficult area.  相似文献   
186.
Susmita Dutta 《Biomarkers》2019,24(4):317-324
Context: Pesticide poisoning and related deaths are a global concern, but there is little information about its effect on the occupationally exposed tea garden workers of North Bengal.

Objective: This study investigates the level of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the blood of the tea garden workers at risk of exposure to a mixture of pesticides.

Materials and methods: The study sample consisted of pesticide exposed workers, non-exposed (control), smokers and alcoholics. AChE and BuChE activity was measured and tested for significance.

Results: Results showed that AChE activity was half in the pesticide exposed individuals than controls (p≤ 0.001). BuChE activity was also significantly decreased in the pesticide exposed individuals than controls (p≤ 0.001), while AChE and BuChE activity in smokers and alcoholics were not different from that of controls. However, significantly decreased AChE and BuChE activities were recorded in pesticide exposed workers compared to smokers and alcoholics.

Conclusions: The results indicated that the decrease in enzyme activities in tea garden workers was due to mixed pesticides (containing organophosphates) exposure. Age was not found to influence the enzyme activities. However, the gender had little effect on the enzyme activities but the effect was not so prominent.  相似文献   

187.

RNA interference (RNAi)-based host-induced gene silencing (HIGS) is emerging as a novel, efficient and target-specific tool to combat phytonematode infection in crop plants. Mi-msp-1, an effector gene expressed in the subventral pharyngeal gland cells of Meloidogyne incognita plays an important role in the parasitic process. Mi-msp-1 effector is conserved in few of the species of root-knot nematodes (RKNs) and does not share considerable homology with the other phytonematodes, thereby making it a suitable target for HIGS with minimal off-target effects. Six putative eggplant transformants harbouring a single copy RNAi transgene of Mi-msp-1 was generated. Stable expression of the transgene was detected in T1, T2 and T3 transgenic lines for which a detrimental effect on RKN penetration, development and reproduction was documented upon challenge infection with nematode juveniles. The post-parasitic nematode stages extracted from the transgenic plants showed long-term RNAi effect in terms of targeted downregulation of Mi-msp-1. These findings suggest that HIGS of Mi-msp-1 enhances nematode resistance in eggplant and protect the plant against RKN parasitism at very early stage.

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Recent report from this lab has shown role of Rac2 in the translocation of inducible nitric oxide synthase (iNOS) to the phagosomal compartment of polymorphonuclear leukocytes (PMNs) following phagocytosis of beads. This study was undertaken to further assess the status and role of tetrahydrobiopterin (BH4), a redox-sensitive cofactor, L-arginine, and the substrate of nitric oxide synthase (NOS) in sustained nitric oxide (˙NO) production in killing of phagocytosed microbes (Escherichia coli) by human PMNs. Time-dependent study revealed consistent NO and reactive oxygen species (ROS) production in the PMNs following phagocytosis of beads. In addition, levels of L-arginine and BH4 were maintained or increased simultaneously to support the enzymatic activity of NOS in the bead activated PMNs. Moreover, translocation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) subunits along with iNOS was reconfirmed in the isolated phagosomes. We demonstrate that increase in the level of NO was supported by L-arginine and BH4 to kill E. coli, by using PMNs from NOS2?/? mice, human PMNs treated with biopterin inhibitor, N-acetyl serotonin (NAS), or by suspending human PMNs in L-arginine deficient medium. Altogether, this study demonstrates that following phagocytosis, sustained. NO production in the PMNs was well-maintained by redox sensitive cofactor, BH4 and substrate, and L-arginine to enable microbial killing. Further results suggest NO production in the human PMNs, along with ROS and myeloperoxidase (MPO) is important to execute antimicrobial activity.  相似文献   
190.
Probiotics and Antimicrobial Proteins - Considering the significance of the gut microbiota on human health, there has been ever-growing research and commercial interest in various aspects of...  相似文献   
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