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71.
Manvir Kaur Anil Kumar Gupta Vikramjit Kaur Zhawar 《Journal of plant biochemistry and biotechnology.》2014,23(1):18-30
Two wheat (Triticum aestivum) cultivars, C306 (drought tolerant) and PBW343 (drought susceptible) were compared for their response to exogenous ABA, water stress (WS) and combined (ABA plus WS) during their seedlings growth. Their responses were studied in the form of seedlings growth, antioxidant potential of roots and shoots and expression levels of LEA genes in shoots. ABA treatment led to increase in levels of ascorbate, ascorbate to dehydroascorbate ratio, antioxidant enzymes and decreases in levels of dehydroascorbate, malondialdehyde (MDA). Decrease in biomass, ascorbate contents, ascorbate to dehydroascorbate ratios and antioxidant enzymes was more in PBW343 than in C306 under WS. Dehydroascorbate and MDA levels were higher in PBW343 than in C306 under WS. ABA plus WS improved some of these features from their levels under WS in PBW343. Proline contents were not increased significantly under ABA in both cultivars. Out of ten LEA genes studied, six LEA genes were induced more under WS than under ABA in C306 but equally induced in PBW343. Four LEA genes were induced earlier in PBW343 but later in C306. Wdhn13 was induced more under ABA than under WS in C306 while it was non-responsive to both stresses in PBW343. 相似文献
72.
73.
The plants of genus Cipadessa, which are distributed across India and southwest of China, have been used as natural insecticides, as well as folk medicines for the treatment of a range of maladies such as diabetes, dysentery, malaria, piles, snake poison, rheumatism, etc. This article reviews the chemical constituents that have been isolated from Cipadessa species to date, including their biological activities. The compounds listed are tetranortriterpenoids (limonoids), diterpenoids, sesquiterpenoids, flavonoids, steroids, and some others. 相似文献
74.
Lan R Geng H Polichnowski AJ Singha PK Saikumar P McEwen DG Griffin KA Koesters R Weinberg JM Bidani AK Kriz W Venkatachalam MA 《American journal of physiology. Renal physiology》2012,302(9):F1210-F1223
We investigated the signaling basis for tubule pathology during fibrosis after renal injury. Numerous signaling pathways are activated physiologically to direct tubule regeneration after acute kidney injury (AKI) but several persist pathologically after repair. Among these, transforming growth factor (TGF)-β is particularly important because it controls epithelial differentiation and profibrotic cytokine production. We found that increased TGF-β signaling after AKI is accompanied by PTEN loss from proximal tubules (PT). With time, subpopulations of regenerating PT with persistent loss of PTEN (phosphate and tension homolog) failed to differentiate, became growth arrested, expressed vimentin, displayed profibrotic JNK activation, and produced PDGF-B. These tubules were surrounded by fibrosis. In contrast, PTEN recovery was associated with epithelial differentiation, normal tubule repair, and less fibrosis. This beneficial outcome was promoted by TGF-β antagonism. Tubule-specific induction of TGF-β led to PTEN loss, JNK activation, and fibrosis even without prior AKI. In PT culture, high TGF-β depleted PTEN, inhibited differentiation, and activated JNK. Conversely, TGF-β antagonism increased PTEN, promoted differentiation, and decreased JNK activity. Cre-Lox PTEN deletion suppressed differentiation, induced growth arrest, and activated JNK. The low-PTEN state with JNK signaling and fibrosis was ameliorated by contralateral nephrectomy done 2 wk after unilateral ischemia, suggesting reversibility of the low-PTEN dysfunctional tubule phenotype. Vimentin-expressing tubules with low-PTEN and JNK activation were associated with fibrosis also after tubule-selective AKI, and with human chronic kidney diseases of diverse etiology. By preventing tubule differentiation, the low-PTEN state may provide a platform for signals initiated physiologically to persist pathologically and cause fibrosis after injury. 相似文献
75.
V Viswanathan S Kumpatla V Aravindalochanan R Rajan C Chinnasamy R Srinivasan JM Selvam A Kapur 《PloS one》2012,7(7):e41367
Background
Diabetes mellitus (DM) is recognised as an important risk factor to tuberculosis (TB). India has high TB burden, along with rising DM prevalence. There are inadequate data on prevalence of DM and pre-diabetes among TB cases in India. Aim was to determine diabetes prevalence among a cohort of TB cases registered under Revised National Tuberculosis Control Program in selected TB units in Tamil Nadu, India, and assess pattern of diabetes management amongst known cases.Methods
827 among the eligible patients (n = 904) underwent HbA1c and anthropometric measurements. OGTT was done for patients without previous history of DM and diagnosis was based on WHO criteria. Details of current treatment regimen of TB and DM and DM complications, if any, were recorded. A pretested questionnaire was used to collect information on sociodemographics, habitual risk factors, and type of TB.Findings
DM prevalence was 25.3% (95% CI 22.6–28.5) and that of pre-diabetes 24.5% (95% CI 20.4–27.6). Risk factors associated with DM among TB patients were age (31–35, 36–40, 41–45, 46–50, >50 years vs <30 years) [OR (95% CI) 6.75 (2.36–19.3); 10.46 (3.95–27.7); 18.63 (6.58–52.7); 11.05 (4.31–28.4); 24.7 (9.73–62.7) (p<0.001)], positive family history of DM [3.08 (1.73–5.5) (p<0.001)], sedentary occupation [1.69 (1.10–2.59) (p = 0.016)], and BMI (18.5–22.9, 23–24.9 and ≥25 kg/m2 vs <18.5 kg/m2) [2.03 (1.32–3.12) (p = 0.001); 0.87 (0.31–2.43) (p = 0.78); 1.44 (0.54–3.8) (p = 0.47)]; for pre-diabetes, risk factors were age (36–40, 41–45, 46–50, >50 years vs <30 years) [2.24 (1.1–4.55) (p = 0.026); 6.96 (3.3–14.7); 3.44 (1.83–6.48); 4.3 (2.25–8.2) (p<0.001)], waist circumference [<90 vs. ≥90 cm (men), <80 vs. ≥80 cm (women)] [3.05 (1.35–6.9) (p = 0.007)], smoking [1.92 (1.12–3.28) (p = 0.017)] and monthly income (5000–10,000 INR vs <5000 INR) [0.59 (0.37–0.94) (p = 0.026)]. DM risk was higher among pulmonary TB [3.06 (1.69–5.52) (p<0.001)], especially sputum positive, than non-pulmonary TB.Interpretation
Nearly 50% of TB patients had either diabetes or pre-diabetes. 相似文献76.
Li L Cao XH Chen SR Han HD Lopez-Berestein G Sood AK Pan HL 《The Journal of biological chemistry》2012,287(8):6002-6013
High voltage-activated calcium channels (HVACCs) are essential for synaptic and nociceptive transmission. Although blocking HVACCs can effectively reduce pain, this treatment strategy is associated with intolerable adverse effects. Neuronal HVACCs are typically composed of α(1), β (Cavβ), and α(2)δ subunits. The Cavβ subunit plays a crucial role in the membrane expression and gating properties of the pore-forming α(1) subunit. However, little is known about how nerve injury affects the expression and function of Cavβ subunits in primary sensory neurons. In this study, we found that Cavβ(3) and Cavβ(4) are the most prominent subtypes expressed in the rat dorsal root ganglion (DRG) and dorsal spinal cord. Spinal nerve ligation (SNL) in rats significantly increased mRNA and protein levels of the Cavβ(3), but not Cavβ(4), subunit in the DRG. SNL also significantly increased HVACC currents in small DRG neurons and monosynaptic excitatory postsynaptic currents of spinal dorsal horn neurons evoked from the dorsal root. Intrathecal injection of Cavβ(3)-specific siRNA significantly reduced HVACC currents in small DRG neurons and the amplitude of monosynaptic excitatory postsynaptic currents of dorsal horn neurons in SNL rats. Furthermore, intrathecal treatment with Cavβ(3)-specific siRNA normalized mechanical hyperalgesia and tactile allodynia caused by SNL but had no significant effect on the normal nociceptive threshold. Our findings provide novel evidence that increased expression of the Cavβ(3) subunit augments HVACC activity in primary sensory neurons and nociceptive input to dorsal horn neurons in neuropathic pain. Targeting the Cavβ(3) subunit at the spinal level represents an effective strategy for treating neuropathic pain. 相似文献
77.
Kalabis J Wong GS Vega ME Natsuizaka M Robertson ES Herlyn M Nakagawa H Rustgi AK 《Nature protocols》2012,7(2):235-246
This protocol describes the isolation and characterization of mouse and human esophageal epithelial cells and the application of 3D organotypic culture (OTC), a form of tissue engineering. This model system permits the interrogation of mechanisms underlying epithelial-stromal interactions. We provide guidelines for isolating and cultivating several sources of epithelial cells and fibroblasts, as well as genetic manipulation of these cell types, as a prelude to their integration into OTC. The protocol includes a number of important applications, including histology, immunohistochemistry/immunofluorescence, genetic modification of epithelial cells and fibroblasts with retroviral and lentiviral vectors for overexpression of genes or RNA interference strategies, confocal imaging, laser capture microdissection, RNA microarrays of individual cellular compartments and protein-based assays. The OTC (3D) culture protocol takes 15 d to perform. 相似文献
78.
Boyer SJ Burke J Guo X Kirrane TM Snow RJ Zhang Y Sarko C Soleymanzadeh L Swinamer A Westbrook J Dicapua F Padyana A Cogan D Gao A Xiong Z Madwed JB Kashem M Kugler S O'Neill MM 《Bioorganic & medicinal chemistry letters》2012,22(1):733-737
A series of inhibitors for the 90 kDa ribosomal S6 kinase (RSK) based on an 1-oxo-2,3,4,5-tetrahydro-1H-[1,4]diazepino[1,2-a]indole-8-carboxamide scaffold were identified through high throughput screening. An RSK crystal structure and exploratory SAR were used to define the series pharmacophore. Compounds with good cell potency, such as compounds 43, 44, and 55 were identified, and form the basis for subsequent kinase selectivity optimization. 相似文献
79.
Saxena AK Rao J Chakrabarty R Saxena M Srimal RC 《Bioorganic & medicinal chemistry letters》2007,17(6):1708-1712
A series of 1-[3-(4-substituted phenylthio) propyl]-4-(substituted phenyl) piperazines has been synthesized and evaluated for hypotensive activity. The QSAR studies indicate that resonance and hydrophobic parameters of the aryl substituents are important for hypotensive activity. The similar role of resonance parameter in describing the variance of 5-HT(2A) receptor binding affinities of these compounds suggests a possible role of 5-HT(2A) receptors in mediating the hypotensive action of title compounds. 相似文献
80.
Although well known for delivering various pharmaceutical agents, liposomes can be prepared to entrap gas rather than aqueous media and have the potential to be used as pressure probes in magnetic resonance imaging (MRI). Using these gas-filled liposomes (GFL) as tracers, MRI imaging of pressure regions of a fluid flowing through a porous medium could be established. This knowledge can be exploited to enhance recovery of oil from the porous rock regions within oil fields. In the preliminary studies, we have optimized the lipid composition of GFL prepared using a simple homogenization technique and investigated key physico-chemical characteristics (size and the physical stability) and their efficacy as pressure probes. In contrast to the liposomes possessing an aqueous core which are prepared at temperatures above their phase transition temperature (T(c)), homogenization of the phospholipids such as 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1,2-distearoyl-sn-glycero-3-phosphocoline (DSPC) in aqueous medium below their T(c) was found to be crucial in formation of stable GFL. DSPC based preparations yielded a GFL volume of more than five times compared to their DPPC counter part. Although the initial vesicle sizes of both DSPC and DPPC based GFL were about 10 microm, after 7 days storage at 25 degrees C, the vesicle sizes of both formulations significantly (p < 0.05) increased to 28.3 +/- 0.3 mum and 12.3 +/- 1.0 microm, respectively. When the DPPC preparation was supplemented with cholesterol at a 1:0.5 or 1:1 molar ratio, significantly (p < 0.05) larger vesicles were formed (12-13 microm), however, compared to DPPC only vesicles, both cholesterol supplemented formulations displayed enhanced stability on storage indicating a stabilizing effect of cholesterol on these gas-filled vesicles. In order to induce surface charge on the GFL, DPPC and cholesterol (1: 0.5 molar ratio) liposomes were supplemented with a cationic surfactant, stearylamine, at a molar ratio of 0.25 or 0.125. Interestingly, the zeta potential values remained around neutrality at both stearylamine ratios suggesting the cationic surfactant was not incorporated within the bilayers of the GFL. Microscopic analysis of GFL confirmed the presence of spherical structures with a size distribution between 1-8 microm. This study has identified that DSPC based GFL in aqueous medium dispersed in 2% w/v methyl cellulose although yielded higher vesicle sizes over time were most stable under high pressures exerted in MRI. 相似文献