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61.
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63.
Baljit Singh Vikrant Sharma Anil Kumar Sanjay Kumar 《International journal of biological macromolecules》2009,45(4):338-347
Psyllium is a medicinally important polysaccharide and its modification with methacrylamide through radiation crosslinked polymerization will develop hydrogels meant for drug delivery applications. The present paper deals with the preparation of hydrogels and their characterization by SEMs, FTIR, TGA and swelling studies. The release dynamics of model antibiotic drug rifampicin from the hydrogels has been studied for the evaluation of the release mechanism. The values of the diffusion exponent ‘n’ have been obtained (0.64, 0.58 and 0.57), respectively, in distilled water, pH 2.2 buffer and pH 7.4 buffer. The release of the drug from the hydrogels occurred through non-Fickian diffusion mechanism. 相似文献
64.
Shinde P Dass RS Garg AK Chaturvedi VK Kumar R 《Biological trace element research》2006,112(3):247-262
Forty weaned male guinea pigs of 208.20±6.62 g mean body weight were divided into 4 groups of 10 animals in a randomized block
design. All of the guinea pigs were fed a basal diet [25% ground maize hay, 30% ground maize grain, 22% ground chickpea (Cicer arietinum L.), 9.5% deoiled rice bran, 6% soybean meal, 6% fish meal, 1.45% mineral supplement (without Zn) and 0.05% ascorbic acid]
and available green fodder. Group I served as the control (no Zn supplementation), whereas 20 ppm Zn was added in the diet
in groups II, III, and IV either as zinc sulfate (ZnSO4), zinc amino acid complex (ZAAC), and ZnSO4
+ ZAAC in equal parts, respectively. Experimental feeding lasted for 70 d, including a 3-d digestibility trial. Blood was collected
through cardiac puncture from four animals in each group at d 0 and subsequently at the end of experimental feeding. After
40 d of experimental feeding, four animals from each group were injected with 0.4 mL of Brucella abortus cotton strain-19 vaccine to assess the humoral immune response of the animals. After 10 wk of study, four animals from each
group were sacrificed to study the concentration of Zn, Cu, Co, Fe, and Mn in the liver, pancreas and spleen. Results revealed
no significant difference in the feed intake, body weight gain, and digestibility of the nutrients, except for crude protein
(CP) digestibility, which was significantly (p<0.05) lower in group IV. Although concentrations of serum glucose, Ca, and P and the albumin:globulin (A:G) ratio were similar
in the different groups, the total protein, albumin, and serum alkaline phosphatase activity were higher in all of the Zn-supplemented
groups on d 70. The serum Zn levels at the end of experimental feeding were significantly higher in groups II and III, whereas
serum Mn levels were found to be significantly (p<0.05) higher in groups III and IV. The organ weights (as percentage of body weights) did not show any differences among the
treatment groups. Although the Mn concentration was significantly (p<0.05) higher in the pancreas, the Cu concentration was significantly (p<0.05) reduced in the spleen in all of the Zn-supplemented groups. The humoral immune response (antibody titer values) on
d 14 of vaccination was significantly (p<0.05) higher in all of the Zn-supplemented groups. It was concluded that the 20-ppm level of Zn in the diet might be adequate
for growth and nutrient utilization in guinea pigs, but supplementation of 20-ppm zinc significantly improved the immune response
and impact was more prominent with the ZAAC (organic source) compared to ZnSO4 (inorganic source). 相似文献
65.
Infection with the Lyme disease pathogen suppresses innate immunity in mice with diet‐induced obesity 下载免费PDF全文
Nataliya Zlotnikov Ashkan Javid Mijhgan Ahmed Azad Eshghi Tian Tian Tang Anoop Arya Anil Bansal Fatima Matar Maitry Parikh Rhodaba Ebady Adeline Koh Nupur Gupta Peng Song Yang Zhang Susan Newbigging Gary P. Wormser Ira Schwartz Robert Inman Michael Glogauer Tara J. Moriarty 《Cellular microbiology》2017,19(5)
Obesity is a major global public health concern. Immune responses implicated in obesity also control certain infections. We investigated the effects of high‐fat diet‐induced obesity (DIO) on infection with the Lyme disease bacterium Borrelia burgdorferi in mice. DIO was associated with systemic suppression of neutrophil‐ and macrophage‐based innate immune responses. These included bacterial uptake and cytokine production, and systemic, progressive impairment of bacterial clearance, and increased carditis severity. B. burgdorferi‐infected mice fed normal diet also gained weight at the same rate as uninfected mice fed high‐fat diet, toll‐like receptor 4 deficiency rescued bacterial clearance defects, which greater in female than male mice, and killing of an unrelated bacterium (Escherichia coli) by bone marrow‐derived macrophages from obese, B. burgdorferi‐infected mice was also affected. Importantly, innate immune suppression increased with infection duration and depended on cooperative and synergistic interactions between DIO and B. burgdorferi infection. Thus, obesity and B. burgdorferi infection cooperatively and progressively suppressed innate immunity in mice. 相似文献
66.
Background
Precision medicine aims to combat the variability of the therapeutic response to a given medicine by delivering the right medicine to the right patient. However, the application of precision medicine is predicated on a prior quantitation of the variance of the reference range of normality. Airway pathophysiology provides a good example due to a very variable first line of defence against airborne assault. Humans differ in their susceptibility to inhaled pollutants and pathogens in part due to the magnitude of trans-epithelial resistance that determines the degree of epithelial penetration to the submucosal space. This initial ‘set-point’ may drive a sentinel event in airway disease pathogenesis. Epithelia differentiated in vitro from airway biopsies are commonly used to model trans-epithelial resistance but the ‘reference range of normality’ remains problematic. We investigated the range of electrophysiological characteristics of human airway epithelia grown at air-liquid interface in vitro from healthy volunteers focusing on the inter- and intra-subject variability both at baseline and after sequential exposure to drugs modulating ion transport.Methodology/Principal Findings
Brushed nasal airway epithelial cells were differentiated at air-liquid interface generating 137 pseudostratified ciliated epithelia from 18 donors. A positively-skewed baseline range exists for trans-epithelial resistance (Min/Max: 309/2963 Ω·cm2), trans-epithelial voltage (-62.3/-1.8 mV) and calculated equivalent current (-125.0/-3.2 μA/cm2; all non-normal, P<0.001). A minority of healthy humans manifest a dramatic amiloride sensitivity to voltage and trans-epithelial resistance that is further discriminated by prior modulation of cAMP-stimulated chloride transport.Conclusions/Significance
Healthy epithelia show log-order differences in their ion transport characteristics, likely reflective of their initial set-points of basal trans-epithelial resistance and sodium transport. Our data may guide the choice of the background set point in subjects with airway diseases and frame the reference range for the future delivery of precision airway medicine. 相似文献67.
We report here a PCR-based cloning methodology that requires no post-PCR modifications such as restriction digestion and phosphorylation of the amplified DNA. The advantage of the present method is that it yields only recombinant clones thus eliminating the need for screening. Two DNA amplification reactions by PCR are performed wherein the first reaction amplifies the gene of interest from a source template, and the second reaction fuses it with the designed expression vector fragments. These vector fragments carry the essential elements that are required for the fusion product selection. The entire process can be completed in less than 8 hours. Furthermore, ligation of the amplified DNA by a DNA ligase is not required before transformation, although the procedure yields more number of colonies upon transformation if ligation is carried out. As a proof-of-concept, we show the cloning and expression of GFP, adh, and rho genes. Using GFP production as an example, we further demonstrate that the E. coli T7 express strain can directly be used in our methodology for the protein expression immediately after PCR. The expressed protein is without or with 6xHistidine tag at either terminus, depending upon the chosen vector fragments. We believe that our method will find tremendous use in molecular and structural biology. 相似文献
68.
Design of liposome to improve encapsulation efficiency of gelonin and its effect on immunoreactivity and ribosome inactivating property 总被引:1,自引:0,他引:1
Anis Alam S. R. K. Bhuri Anil K. Mavila Vinod Singh 《Molecular and cellular biochemistry》1992,112(2):97-109
Gelonin, purified from the seeds of Gelonium multiflorum, using cation-exchange and gel-filtration chromatography was characterised for its purity, homogeneity and molecular weight by reverse-phase HPLC (RP-HPLC) and SDS-PAGE analysis. The HPLC purified gelonin was used for entrapment studies in the liposomes. Liposomes were prepared by reverse phase evaporation (REV) technique using three different types of lipid composition in the same molar ratio. The method resulted in 75–80% entrapment efficiency of gelonin in the liposomes. Entrapped and unentrapped gelonin was characterized for physico-chemical, immunochemical and biological properties. The immunoreactivity of entrapped gelonin was fully preserved but the ribosome-inactivating property was slightly inhibited. The method involved mild conditions, highly reproducible and the liposomes produced appeared to be stable for several months. It has important implications in the development of cell type specific cytotoxic agents where a chemical cross-linking is involved which significantly inhibits both immunoreactivity and ribosome-inactivating ability of the toxin. 相似文献
69.
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
70.
K. P. Shyma Sachin Kumar Anil Kumar Sharma D. D. Ray S. Ghosh 《Experimental & applied acarology》2012,58(4):471-481
The multi host tick, Hyalomma anatolicum, is the commonest Hyalomma species in India and cattle serves as the main host of this species. A study to evaluate the acaricide resistance of H. anatolicum to deltamethrin, cypermethrin and diazinon was conducted in 20 areas located in three agro climatic regions known to have abundance of the species. Results obtained by the “larval packet test” (LPT) showed a low grade resistance (level-I, RF?<5) in the tick species to both deltamethrin and cypermethrin in 10 areas and higher grade resistance (level-II, RF?<25) to deltamethrin in one area, where intensive use of synthetic pyrethroids are practiced for tick control. Low grade resistance to diazinon (level I) was recorded in six areas where organophosphates compounds are extensively used for agricultural practices allowing increased exposure of the moulting instars of the ticks to these chemicals. Biochemical analysis of the samples suggested involvement of esterase and alterations of acetylcholinesterase in the resistance mechanisms. 相似文献