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81.

Background  

Identification of novel drug targets and their inhibitors is a major challenge in the field of drug designing and development. Diaminopimelic acid (DAP) pathway is a unique lysine biosynthetic pathway present in bacteria, however absent in mammals. This pathway is vital for bacteria due to its critical role in cell wall biosynthesis. One of the essential enzymes of this pathway is dihydrodipicolinate synthase (DHDPS), considered to be crucial for the bacterial survival. In view of its importance, the development and prediction of potent inhibitors against DHDPS may be valuable to design effective drugs against bacteria, in general.  相似文献   
82.
The aim of the present work was to study the effects of an unilateral ischaemic-reperfusion injury on Na+, K+-ATPase activity, α1 and β1 subunits protein and mRNA abundance and ATP content in cortical and medullary tissues from postischaemic and contralateral kidneys. Right renal artery was clamped for 40 min followed by 24 and 48 h of reperfusion. Postischaemic and contralateral renal function was studied cannulating the ureter of each kidney. Postischaemic kidneys after 24 (IR24) and 48 (IR48) hours of reperfusion presented a significant dysfunction. Na+, K+-ATPase α1 subunit abundance increased in IR24 and IR48 cortical tissue and β1 subunit decreased in IR48. In IR24 medullary tissue, α1 abundance increased and returned to control values in IR48 while β1 abundance was decreased in both periods. Forty minutes of ischaemia without reperfusion (I40) promoted an increment in α1 mRNA in cortex and medulla that normalised after 24 h of reperfusion. β1 mRNA was decreased in IR24 medullas. No changes were observed in contralateral kidneys. This work provides evidences that after an ischaemic insult α1 and β1 protein subunit abundance and mRNA levels are independently regulated. After ischaemic-reperfusion injury, cortical and medullary tissue showed a different pattern of response. Although ATP and Na+, K+-ATPase activity returned to control values, postischemic kidney showed an abnormal function after 48 h of reflow.  相似文献   
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The breeding habitat of sandflies is a little studied and poorly understood phenomenon. More importantly, oviposition behaviour is a largely neglected aspect of sandfly biology and this knowledge gap further undermines our understanding of the biology of sandflies. Pheromones released by the eggs play an important role in identifying good sites for oviposition by female insects. Several recent studies have examined the oviposition pheromone. The present study provides a preliminary report on the oviposition behaviour of Phlebotomus argentipes, the only vector of kala-azar (or visceral leishmaniasis) on the Indian sub-continent. Sandflies prefer to oviposit their eggs on surfaces that contain organic substances, especially substances with an odour of decaying animal products and the remains of conspecific eggs. The results presented here suggest that the odour released by the organic substances of old sandfly colony remains that contain dead flies, old unhatched eggs, larval food containing vertebrate faeces, frass and other organic matter serves as an attractant for the ovipositing females of P. argentipes and hence greatly increases the number of oviposited eggs compared to eggs deposited in controlled oviposition pots. This result will be helpful in maintaining an efficient colony of P. argentipes and may be a promising tool for monitoring and controlling the target insect as part of a synergistic approach.  相似文献   
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Abstract

The present investigation was aimed to determine the anti-pathogenic, antibiofilm, and technological properties of fermented food associated Staphylococcus succinus strain AAS2. The anti-pathogenic attribute of cell-free neutralized supernatant (CFNS) of strain AAS2 was assessed against food-borne and enteric pathogens that revealed promising activity against Staphylococcus aureus and Enterobacter aerogenes with high arbitrary unit of 220.25?±?3.3 and 170.2?±?4.6?AU/mL, respectively. Furthermore, the antibiofilm and time-kill assay of CFNS of strain AAS2 depicted remarkable reduction in biofilm formation of indicator pathogens in a dose-dependent manner. Moreover, time-kill assay data revealed the drastic reduction in the viability (log cfu/mL) of S. aureus and E. aerogenes in the presence of varied minimum inhibitory concentration ranges of CFNS. The distinct technological properties of strain AAS2 were demonstrated using standard methodologies. Reported results estimated moderate level of exopolysaccharide (41.3?±?0.6?mg/L) and lipase production (8.3?±?0.3?mm), followed by remarkable autolytic (30.1?±?1.2–43.1?±?1.3%), catalase (13.82?±?0.3?AU), and nitrate reductase (10.25?±?0.3?mM nitrite/mg dry weight) activities under standard conditions. Most importantly, the strain cleared the specific in vitro safety assessment tests. The described anti-pathogenic and technological traits of strain AAS2 paved the way to utilize it in pharmaceutical as well as food processing industries as starter/adjunct culture.  相似文献   
88.
New carbohydrate-conjugated heterobimetallic complexes [C(32)H(62)N(10)O(8)NiSn(2)Cl(4)]Cl(2)(1) and [C(32)H(62)N(10)O(8)CuSn(2)Cl(4)]Cl(2) (2) were synthesized and characterized by spectroscopic (IR, (1)H, (13)C, and (119)Sn NMR, EPR, UV-vis, ESI-MS) and analytical methods. The interaction studies of 2 with CT DNA were studied by using various biophysical techniques, which showed high binding affinity of 2 toward CT DNA. The extent of interaction was further confirmed by the interaction of 2 with the nucleotides viz.; 5'-AMP, 5'-CMP, 5'-GMP, and 5'-TMP, by absorption titration. (1)H, (31)P, (119)Sn NMR spectroscopy further validated the interaction mode of 2 with 5'-GMP. The electrophoresis pattern observed for 2 with supercoiled pBR322 DNA, exhibited significantly good nuclease activity following oxidative pathway. The preferential selectivity of 2 toward the major groove was observed on interaction of 2 with pBR322 DNA, in the presence of standard groove binders viz.; DAPI and methyl green. Additionally, in vitro antitumor activity of 2 was evaluated on a panel of human cancer cell lines, exhibiting remarkable cytotoxicity activity against Colo205 (colon) and MCF7 (breast) cell lines with GI(50) values <10 μg/mL.  相似文献   
89.
The precise functions of most of the ~200 assembly factors and 79 ribosomal proteins required to construct yeast ribosomes in vivo remain largely unexplored. To better understand the roles of these proteins and the mechanisms driving ribosome biogenesis, we examined in detail one step in 60S ribosomal subunit assembly-processing of 27SA(3) pre-rRNA. Six of seven assembly factors required for this step (A(3) factors) are mutually interdependent for association with preribosomes. These A(3) factors are required to recruit Rrp17, one of three exonucleases required for this processing step. In the absence of A(3) factors, four ribosomal proteins adjacent to each other, rpL17, rpL26, rpL35, and rpL37, fail to assemble, and preribosomes are turned over by Rat1. We conclude that formation of a neighbourhood in preribosomes containing the A(3) factors establishes and maintains stability of functional preribosomes containing 27S pre-rRNAs. In the absence of these assembly factors, at least one exonuclease can switch from processing to turnover of pre-rRNA.  相似文献   
90.

Background

We have previously investigated the microlocalisation of M1 and M2 macrophages in NSCLC. This study investigated the non-macrophage (NM) expression of proteins associated with M1 and M2 macrophages in NSCLC.

Methods

Using immunohistochemistry, CD68+ macrophages and proteins associated with either a cytotoxic M1 phenotype (HLA-DR, iNOS, and MRP 8/14), or a non-cytotoxic M2 phenotype (CD163 and VEGF) were identified. NM expression of the markers was analysed in the islets and stroma of surgically resected tumours from 20 patients with extended survival (ES) (median 92.7 months) and 20 patients with poor survival (PS) (median 7.7 months).

Results

The NM expression of NM-HLA-DR (p<0.001), NM-iNOS (p = 0.02) and NM-MRP 8/14 (p = 0.02) was increased in ES compared to PS patients in the tumour islets. The tumour islet expression of NM-VEGF, was decreased in ES compared to PS patients (p<0.001). There was more NM-CD163 expression (p = 0.04) but less NM-iNOS (p = 0.002) and MRP 8/14 (p = 0.01) expression in the stroma of ES patients compared with PS patients. The 5-year survival for patients with above and below median NM expression of the markers in the islets was 74.9% versus 4.7% (NM-HLA-DR p<0.001), 65.0% versus 14.6% (NM-iNOS p = 0.003), and 54.3% versus 22.2% (NM-MRP 8/14 p = 0.04), as opposed to 34.1% versus 44.4% (NM-CD163 p = 0.41) and 19.4% versus 59.0% (NM-VEGF p = 0.001).

Conclusions

Cell proteins associated with M1 and M2 macrophages are also expressed by other cell types in the tumour islets and stroma of patients with NSCLC. Their tissue and cellular microlocalisation is associated with important differences in clinical outcome.  相似文献   
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