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91.

Objective

To determine whether erythropoietin given during hemorrhagic shock (HS) ameliorates organ injury while improving resuscitation and survival.

Methods

Three series of 24 pigs each were studied. In an initial series, 50% of the blood volume (BV) was removed in 30 minutes and normal saline (threefold the blood removed) started at minute 90 infusing each third in 30, 60, and 150 minutes with shed blood reinfused at minute 330 (HS-50BV). In a second series, the same HS-50BV protocol was used but removing an additional 15% of BV from minute 30 to 60 (HS-65BV). In a final series, blood was removed as in HS-65BV and intraosseous vasopressin given from minute 30 (0.04 U/kg min−1) until start of shed blood reinfusion at minute 150 (HS-65BV+VP). Normal saline was reduced to half the blood removed and given from minute 90 to 120 in half of the animals. In each series, animals were randomized 1∶1 to receive erythropoietin (1,200 U/kg) or control solution intraosseously after removing 10% of the BV.

Results

In HS-50BV, O2 consumption remained near baseline yielding minimal lactate increases, 88% resuscitability, and 60% survival at 72 hours. In HS-65BV, O2 consumption was reduced and lactate increased yielding 25% resuscitability. In HS-65BV+VP, vasopressin promoted hemodynamic stability yielding 92% resuscitability and 83% survival at 72 hours. Erythropoietin did not affect resuscitability or subsequent survival in any of the series but increased interleukin-10, attenuated lactate increases, and ameliorated organ injury based on lesser troponin I, AST, and ALT increases and lesser neurological deficits in the HS-65BV+VP series.

Conclusions

Erythropoietin given during HS in swine failed to alter resuscitability and 72 hour survival regardless of HS severity and concomitant treatment with fluids and vasopressin but attenuated acute organ injury. The studies also showed the efficacy of vasopressin and restrictive fluid resuscitation for hemodynamic stabilization and survival.  相似文献   
92.
Three pseudomonad strains (MKRh1, MKRh3, and MKRh4) isolated from rhizospheres showed a high growth potential in the presence of cadmium, with a minimal inhibitory concentration of 7 mM for cadmium chloride (CdCl2). Among them, isolate MKRh3 was specifically chosen as the most favorable cadmium-resistant plant growth-promoting rhizobacterium based on its higher 1-aminocyclopropane carboxylic acid deaminase activity, siderophore production, phosphate solubilization, and auxin synthesis and the in vivo growth increment of black gram plants. 16S ribosomal RNA gene sequencing identified MKRh3 as Pseudomonas aeruginosa. The effect of cadmium on black gram plants was studied in soil amended with a gradient of CdCl2 concentration and the toxicity was evident from stunted growth, poor rooting, and cadmium accumulation. Application of isolate MKRh3 by seed coating overcomes the cadmium toxicity; plants showed lessened cadmium accumulation, extensive rooting, and enhanced plant growth. Further research and development of this promising innate strategy for scale-up to higher-efficiency and large-scale application will be a potent tool to prevent accumulation of cadmium in plants, thereby ensuring food security for humans.  相似文献   
93.
The medicinal and physicochemical properties of nanoscale materials are strong functions of the particle size and the materials used in their synthesis. The nanoparticle shape also contributes significantly to their medicinal properties. Several shapes ranging from oval, spherical, rods, to teardrop structures may be obtained by chemical methods. Triangular and hexagonal nanoparticles have been synthesized by using a pine cone extract (PCE). Here, we report the discovery that PCE, when reacted with silver nitrate ions, yields a high percentage of thin, flat, single-crystalline nanohexagonal and nanotriangular silver nanoparticles. The nanohexagonal and nanotriangular nanoparticles appear to grow by a process involving rapid reduction with assembly at room temperature at a high pH. The nanoparticles were characterized by UV–Vis absorption spectroscopy, SEM-EDS, TEM, FTIR, and X-ray diffraction analyses. The anisotropy of the nanoparticle shape results in large near-infrared absorption by the particles. Highly anisotropic particles are applicable in various fields, including agriculture and medicine. The obtained silver nanoparticles (Ag NPs) had significant antibacterial action on both Gram classes of bacteria associated with agriculture. Because the Ag NPs are encapsulated with functional group-rich PCE, they can be easily integrated in various applications.  相似文献   
94.
Starch grains present in the endosperm of grains of common buckwheat (Fagopyrum esculentum Moench) show a monomodal distribution with size ranging from 4 to 10 μm. SDS-PAGE analysis of starch granule bound proteins revealed the presence of a single band corresponding to molecular mass of 59.7 kDa. The protein is localized within the central core of the starch grains. Antisera raised against the 59.7 kDa protein cross reacted with the 61 kDa GBSS-I from endosperm starches of maize and the 60 kDa GBSS-I from endosperm starches of rice and wheat, thereby indicating serological homology between the 59.7 kDa buckwheat starch granule bound protein and GBSS-I of wheat, maize and rice. 2D-PAGE of starch granule bound proteins of common buckwheat resolved the fraction into 7 spots with pI ranging from 5.2 to 5.6. N-terminal amino acid sequence for 25 residues of two immunoreactive proteins separated by 2D PAGE showed 94 % homology with N-terminal amino acid sequence of GBSS-I from Hordeum vulgare, Triticum spp. and Phaseolus vulgaris. Even though analysis of the sequence alignment revealed a clear diversification into monocotyledonous and dicotyledonous groups, the protein from buckwheat showed similarities with GBSS-I from both dicots as well as monocots. As is the case with dicots, the sequence of GBSS-I from buckwheat has valine as the 11th residue. GBSS-I from majority of monocots has methionine at this position. The sequence also showed similarities with monocots with valine at P’5 from the N-terminus. GBSS-I from majority of dicots has isoleucine at this position. The significance of these substitution remains to be ascertained.  相似文献   
95.
Biogeochemical and microbiological characterization of marine sediments taken from the Yellow Sea of South Korea was carried out. One hundred and thirty six bacterial strains were isolated, characterized and phylogenetic relationship was evaluated. The gene sequences of 16S rDNA regions were examined to study the phylogenetic analysis of bacterial community in the marine sediments. Among 136 isolates, 5 bacterial isolates were identified as novel members, remaining 131 isolates were fall into 5 major linkages of bacterial phyla represented as follows: Firmicutes, alpha, gamma-Proteobacteria, High G + C and Bacteroidetes. Bacterial community in sediments mainly dominated by Firmicutes (58.77%) and followed by gamma-Pateobacteria (38.16%). Gamma-Proteobacteria domain highly diverged and mainly consists of the genera Vibrio, Marinobacterium, Photobacterium, Pseudoalteromonas, Oceanisphaera, Halomonas, Alteromonas, Stenotrophomonas and Pseudomonas. Total N and Organic matter content in Yellow Sea of South Korea were relatively high. The Total-N content in the sediments was varied from 177.31 to 1974.96 (mg/kg) and organic matter ranged from 0.82 to 4.23 (g/100 g). The current research work provides clear explanation obtained for the phylogenetic affiliation of the culturable bacterial community in sediments of South Korean Yellow Sea and revealed the relationship with biogeochemical characteristics of the sediments.  相似文献   
96.
Archives of Microbiology - Acinetobacter baumannii has emerged worldwide as a leading cause of hospital-acquired infections. Although A. baumannii was initially regarded...  相似文献   
97.
Human Fc receptors (FcγR) are membrane glycoproteins that are expressed on all immunologically active cells and have a well-defined role in regulating innate and adaptive immune responses by binding to the immunoglobulin G (IgG) antibody. Among the several classes of Fc receptors, FcγRIIa is the most widely expressed, and it serves as an important reagent in antibody engineering. Here, we report on high cell density cultivations (HCDC) of Escherichia coli for preparative scale production of FcγRIIa in a 6.6L bioreactor. Briefly, a pH-stat feeding strategy was employed, and two different cell densities (OD(600) of 46 and 100) were examined for the induction of FcγRIIa gene expression. When cells were induced at a high cell density (OD(600) of 100), the cell density increased to an OD(600) of 234 within 9h after induction, and a 2-fold higher production yield was obtained compared with that of induction at low cell density (OD(600) of 46). After simple purification steps including denaturation and refolding, 87.7 mg of soluble FcγRIIa that was more than 95% pure was obtained from a 20-mL culture with high recovery yield (≈54%). The biological activity of purified FcγRIIa was also confirmed by evaluating its interaction with all subclasses of IgG antibodies using an ELISA bioassay.  相似文献   
98.
99.
4-[(1Z)-1-(2-carbamothioylhydrazinylidene)ethyl]phenyl acetate [Ace semi],4-[(1Z)-1-(2-carbamothioylhydrazinylidene)ethyl]phenyl propanoate [Pro semi] from the family of thiosemicarbazones derivative has been newly synthesized. It has good anticancer activity as well as antibacterial and it is also less toxic in nature, its binding characteristics are therefore of huge interest for understanding pharmacokinetic mechanism of the drug. The binding of thiosemicarbazone derivative to human serum albumin (HSA) has been investigated by studying its quenching mechanism, binding kinetics and the molecular distance (r) between donor (HSA) and acceptor (thiosemicarbazone derivative) was estimated according to Forster’s theory of non-radiative energy transfer using fluorescence spectroscopy. The binding dynamics has been elaborated using synchronous fluorescence spectroscopy, and the feature of thiosemicarbazone derivative induced structural changes of HSA has been studied by circular dichorism, Fourier transform infrared spectroscopy. Molecular modelling simulations explore the hydrophobic interaction and hydrogen bonding which stabilizes the interaction.  相似文献   
100.
This study highlights the ability of nitrate-reducing Bacillus subtilis EWP-46 cell-free extract used for preparation of silver nanoparticles (AgNPs) by reduction of silver ions into nano silver. The production of AgNPs was optimized with several parameters such as hydrogen ion concentration, temperature, silver ion (Ag+ ion) and time. The maximum AgNPs production was achieved at pH 10.0, temperature 60 °C, 1.0 mM Ag+ ion and 720 min. The UV–Vis spectrum showed surface plasmon resonance peak at 420 nm, energy-dispersive X-ray spectroscopy (SEM–EDX) spectra showed the presence of element silver in pure form. Atomic force microscopy (AFM) and transmission electron microscopy images illustrated the nanoparticle size, shape, and average particle size ranging from 10 to 20 nm. Fourier transform infrared spectroscopy provided the evidence for the presence of biomolecules responsible for the reduction of silver ion, and X-ray diffraction analysis confirmed that the obtained nanoparticles were in crystalline form. SDS-PAGE was performed to identify the proteins and its molecular mass in the purified nitrate reductase from the cell-free extract. In addition, the minimum inhibitory concentration and minimum bactericidal concentration of AgNPs were investigated against gram-negative (Pseudomonas fluorescens) and gram-positive (Staphylococcus aureus) bacteria.  相似文献   
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