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41.
Praziquantel derivatives I: Modification of the aromatic ring 总被引:1,自引:0,他引:1
Ronketti F Ramana AV Chao-Ming X Pica-Mattoccia L Cioli D Todd MH 《Bioorganic & medicinal chemistry letters》2007,17(15):4154-4157
Several analogues of the potent anthelmintic praziquantel were prepared with variation in the aromatic ring. The biological activity of these analogues was evaluated and compared against known analogues. Amination of the ring was tolerated while other variations were not. These results have important implications for drug development for schistosomiasis. 相似文献
42.
Proprioception plays an important role in appropriate sensation of spine position, movement, and stability. Previous research has demonstrated that position sense error in the lumbar spine is increased in flexed postures. This study investigated the change in position sense as a function of altered trunk flexion and moment loading independently. Reposition sense of lumbar angle in 17 subjects was assessed. Subjects were trained to assume specified lumbar angles using visual feedback. The ability of the subjects to reproduce this curvature without feedback was then assessed. This procedure was repeated for different torso flexion and moment loading conditions. These measurements demonstrated that position sense error increased significantly with the trunk flexion (40%, p < .05) but did not increase with moment load (p = .13). This increased error with flexion suggests a loss in the ability to appropriately sense and therefore control lumbar posture in flexed tasks. This loss in proprioceptive sense could lead to more variable lifting coordination and a loss in dynamic stability that could increase low back injury risk. This research suggests that it is advisable to avoid work in flexed postures. 相似文献
43.
Mesenchymal Stem Cells from Rat Bone Marrow Downregulate Caspase-3-mediated Apoptotic Pathway After Spinal Cord Injury in Rats 总被引:6,自引:0,他引:6
Mesenchymal stem cells have been intensively studied for their potential use in reparative strategies for neurodegenerative
diseases and traumatic injuries. We used mesenchymal stem cells (rMSC) from rat bone marrow to evaluate the therapeutic potential
after spinal cord injury (SCI). Immunohistochemistry confirmed a large number of apoptotic neurons and oligodendrocytes in
caudal segments 2 mm away from the lesion site. Expression of caspase-3 on both neurons and oligodendrocytes after SCI was
significantly downregulated by rMSC. Caspase-3 downregulation by rMSC involves increased expression of FLIP and XIAP in the
cytosol and inhibition of PARP cleavage in the nucleus. Animals treated with rMSC had higher Basso, Beattie, Bresnahan (BBB)
locomotor scoring and better recovery of hind limb sensitivity. Treatment with rMSC had a positive effect on behavioral outcome
and histopathological assessment after SCI. The ability of rMSC to incorporate into the spinal cord, differentiate and to
improve locomotor recovery hold promise for a potential cure after SCI.
Special issue in honor of Naren Banik. 相似文献
44.
Yeast two-hybrid and Far Western analyses were used to detect interactions between Bacillus subtilis spores' nutrient germinant receptor proteins and proteins encoded by the spoVA operon, all of which are involved in spore germination and located in the spores' inner membrane. These analyses indicated that two subunits of the GerA nutrient germinant receptor interact, consistent with previous genetic data, and that some GerA proteins interact with SpoVAD and some with SpoVAE. SpoVA proteins appear to be involved in the release of the spore's dipicolinic acid during spore germination, an event triggered by the binding of nutrient germinants to their receptors. Consequently, these new findings suggest that nutrient germinant receptors physically contact SpoVA proteins, and presumably this is a route for signal transduction during spore germination. 相似文献
45.
Gao Xiang Uno Kenichi Sarr Papa Saliou Yoshihashi Tadashi Zhu Yiyong Subbarao Guntur Venkata 《Plant and Soil》2022,477(1-2):793-805
Plant and Soil - Rapid nitrification leads to loss of nitrogen (N) fertilizer in agricultural systems. Plant produced/derived biological nitrification inhibitors (BNIs) are an effective... 相似文献
46.
47.
Virus‐induced gene silencing of Withania somnifera squalene synthase negatively regulates sterol and defence‐related genes resulting in reduced withanolides and biotic stress tolerance 下载免费PDF全文
48.
Demographic and clinical variables affecting mid‐ to late‐life trajectories of plasma ceramide and dihydroceramide species 下载免费PDF全文
Michelle M. Mielke Veera Venkata Ratnam Bandaru Dingfen Han Yang An Susan M. Resnick Luigi Ferrucci Norman J. Haughey 《Aging cell》2015,14(6):1014-1023
It has been increasingly recognized at the basic science level that perturbations in ceramide metabolism are associated with the development and progression of many age‐related diseases. However, the translation of this work to the clinic has lagged behind. Understanding the factors longitudinally associated with plasma ceramides and dihydroceramides (DHCer) at the population level and how these lipid levels change with age, and by sex, is important for the clinical development of future therapeutics and biomarkers focused on ceramide metabolism. We, therefore, examined factors cross‐sectionally and longitudinally associated with plasma concentrations of ceramides and DHCer among Baltimore Longitudinal Study of Aging participants (n = 992; 3960 total samples), aged 55 years and older, with plasma at a mean of 4.1 visits (range 2–6). Quantitative analyses were performed on a high‐performance liquid chromatography‐coupled electrospray ionization tandem mass spectrometer. Linear mixed models were used to assess the relationships between plasma ceramide and DHCer species and demographics, diseases, medications, and lifestyle factors. Women had higher plasma concentrations of most ceramide and DHCer species and showed steeper trajectories of age‐related increases compared to men. Ceramides and DHCer were more associated with waist–hip ratio than body mass index. Plasma cholesterol and triglycerides, prediabetes, and diabetes were associated with ceramides and DHCer, but the relationship showed specificity to the acyl chain length and saturation. These results demonstrate the importance of examining the individual species of ceramides and DHCer, and of establishing whether intra‐individual age‐ and sex‐specific changes occur in synchrony to disease onset and progression. 相似文献
49.
Pallapolu VR Lee YY Garlock RJ Balan V Dale BE Kim Y Mosier NS Ladisch MR Falls M Holtzapple MT Sierra-Ramirez R Shi J Ebrik MA Redmond T Yang B Wyman CE Donohoe BS Vinzant TB Elander RT Hames B Thomas S Warner RE 《Bioresource technology》2011,102(24):11115-11120
The objective of this work is to investigate the effects of cellulase loading and β-glucosidase supplementation on enzymatic hydrolysis of pretreated Dacotah switchgrass. To assess the difference among various pretreatment methods, the profiles of sugars and intermediates were determined for differently treated substrates. For all pretreatments, 72 h glucan/xylan digestibilities increased sharply with enzyme loading up to 25 mg protein/g-glucan, after which the response varied depending on the pretreatment method. For a fixed level of enzyme loading, dilute sulfuric acid (DA), SO2, and Lime pretreatments exhibited higher digestibility than the soaking in aqueous ammonia (SAA) and ammonia fiber expansion (AFEX). Supplementation of Novozyme-188 to Spezyme-CP improved the 72 h glucan digestibility only for the SAA treated samples. The effect of β-glucosidase supplementation was discernible only at the early phase of hydrolysis where accumulation of cellobiose and oligomers is significant. Addition of β-glucosidase increased the xylan digestibility of alkaline treated samples due to the β-xylosidase activity present in Novozyme-188. 相似文献
50.
Ram Reddy T Srinivasula Reddy L Rajeshwar Reddy G Nuthalapati VS Lingappa Y Sandra S Kapavarapu R Misra P Pal M 《Bioorganic & medicinal chemistry letters》2011,21(21):6433-6439
A multi component based synthesis involving palladium catalyzed C-C bond forming reaction has been developed as a new strategy to access systematically modified functionalized 2-aminochromenes. This MCR involves the use of bromobenzaldehyde as a key component and is highlighted by generating a new compound library. Many of these compounds showed Mycobacterium tuberculosis H37Rv chorismate mutase inhibiting properties in vitro representing the lead example of chorismate mutase inhibition by heteroarene based compounds. 相似文献