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1.
Bleeding complication and abnormal platelet functions are associated with liver cirrhosis. The aim of the present investigation was to assess the functional integrity of platelets in terms of lipids like cholesterol and phospholipids, glycoproteins and membrane-bound enzymes. Liver cirrhotic patients with bleeding complications were studied. Age and sex matched normal healthy volunteers were also involved in this study as a control group. Levels of cholesterol, phospholipids, glycoproteins and adenosine triphosphatases were assessed in isolated platelet membrane fraction. The level of glycoproteins and the activity of adenosine triphosphatases were found to be decreased significantly in cirrhotic patients. The cholesterol/phospholipid ratio was found to be altered significantly, indicating an alteration in the fluidity of platelet membrane. The results of this study reveal that the functional impairment of platelets in liver cirrhotic patients which is responsible for their bleeding tendency might also be due to altered lipid and enzyme levels in platelet membrane.  相似文献   
2.
Various forms of stress have been shown to alter natural killer (NK) cell activity and tumorigenesis; however, few studies have measured these two variables simultaneously. Isolation of mice was utilized as a model of stress by which to study NK cell activity and pulmonary metastatic response following a tumor challenge. Male C3H mice were group or individually housed for 3 weeks, after which CIRAS 3 fibrosarcoma tumor cells or the tumor vehicle was injected intravenously (tail vein), NK cell activity, pulmonary metastasis, and plasma corticosterone were measured 1, 7, and 21 days following tumor cell inoculation. Individually housed mice, irrespective of tumor or vehicle condition, had a higher NK response on Day 1 relative to group-housed animals (P less than 0.001). By Day 21, tumor condition, rather than housing, was the major significant factor affecting NK activity (P less than 0.001). Nevertheless, individually housed, tumor-injected mice still had higher NK activity compared with the other treatment groups on Day 21. No effect of housing condition was present for the incidence of pulmonary metastases or frequency of metastases in affected animals. Plasma corticosterone levels generally increased over the study period, with no housing or injection effects at Days 1 and 7. Individually housed, vehicle-injected mice had higher corticosterone levels at Day 21 (P less than 0.01). These data suggest that in response to housing condition, NK cell activity differs in tumor-bearing mice and vehicle controls. Furthermore, CIRAS 3 pulmonary tumor formation is not affected by differences in NK activity consequent to housing condition. Plasma corticosterone does not appear to be a major in vivo regulator of NK activity in this experimental tumor system. Finally, the interpretation of housing effects on NK activity and plasma corticosterone levels depends on the temporal window in which sampling occurs.  相似文献   
3.
Multi-protein complexes, termed “inflammasomes,” are known to contribute to neuronal cell death and brain injury following ischemic stroke. Ischemic stroke increases the expression and activation of nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) Pyrin domain containing 1 and 3 (NLRP1 and NLRP3) inflammasome proteins and both interleukin (IL)-1β and IL-18 in neurons. In this study, we provide evidence that activation of either the NF-κB and MAPK signaling pathways was partly responsible for inducing the expression and activation of NLRP1 and NLRP3 inflammasome proteins and that these effects can be attenuated using pharmacological inhibitors of these two pathways in neurons and brain tissue under in vitro and in vivo ischemic conditions, respectively. Moreover, these findings provided supporting evidence that treatment with intravenous immunoglobulin (IVIg) preparation can reduce activation of the NF-κB and MAPK signaling pathways resulting in decreased expression and activation of NLRP1 and NLRP3 inflammasomes, as well as increasing expression of anti-apoptotic proteins, Bcl-2 and Bcl-xL, in primary cortical neurons and/or cerebral tissue under in vitro and in vivo ischemic conditions. In summary, these results provide compelling evidence that both the NF-κB and MAPK signaling pathways play a pivotal role in regulating the expression and activation of NLRP1 and NLRP3 inflammasomes in primary cortical neurons and brain tissue under ischemic conditions. In addition, treatment with IVIg preparation decreased the activation of the NF-κB and MAPK signaling pathways, and thus attenuated the expression and activation of NLRP1 and NLRP3 inflammasomes in primary cortical neurons under ischemic conditions. Hence, these findings suggest that therapeutic interventions that target inflammasome activation in neurons may provide new opportunities in the future treatment of ischemic stroke.  相似文献   
4.
There is a critical need to evaluate lithium–sulfur (Li–S) batteries with practically relevant high sulfur loadings and minimal electrolyte. Under such conditions, the concentration of soluble polysulfide intermediates in the electrolyte drastically increases, which can alter the fundamental nature of the solution‐mediated discharge and thereby the total sulfur utilization. In this work, an investigation into various high donor number (DN) electrolytes that allow for increased polysulfide dissolution is presented, and the way in which this property may in fact be necessary for increasing sulfur utilization at low electrolyte and high loading conditions is demonstrated. The solvents dimethylacetamide, dimethyl sulfoxide, and 1‐methylimidazole are holistically evaluated against dimethoxyethane as electrolyte co‐solvents in Li–S cells, and they are used to investigate chemical and electrochemical properties of polysulfide species at both dilute and practically relevant conditions. The nature of speciation exhibited by lithium polysulfides is found to vary significantly between these concentrations, particularly with regard to the S3?? species. Furthermore, the extent of the instability in conventional electrolyte solvents and high DN solvents with both lithium metal and polysulfides is thoroughly investigated. These studies establish a basis for future efforts into rationally designing an optimal electrolyte for a lean electrolyte, high energy density Li–S battery.  相似文献   
5.
Intensive studies of an advanced energy material are reported and lithium polyacrylate (LiPAA) is proven to be a surprisingly unique, multifunctional binder for high‐voltage Li‐ion batteries. The absence of effective passivation at the interface of high‐voltage cathodes in Li‐ion batteries may negatively affect their electrochemical performance, due to detrimental phenomena such as electrolyte solution oxidation and dissolution of transition metal cations. A strategy is introduced to build a stable cathode–electrolyte solution interphase for LiNi0.5Mn1.5O4 (LNMO) spinel high‐voltage cathodes during the electrode fabrication process by simply using LiPAA as the cathode binder. LiPAA is a superb binder due to unique adhesion, cohesion, and wetting properties. It forms a uniform thin passivating film on LNMO and conducting carbon particles in composite cathodes and also compensates Li‐ion loss in full Li‐ion batteries by acting as an extra Li source. It is shown that these positive roles of LiPAA lead to a significant improvement in the electrochemical performance (e.g., cycle life, cell impedance, and rate capability) of LNMO/graphite battery prototypes, compared with that obtained using traditional polyvinylidene fluoride (PVdF) binder for LNMO cathodes. In addition, replacing PVdF with LiPAA binder for LNMO cathodes offers better adhesion, lower cost, and clear environmental advantages.  相似文献   
6.
Quantitative trait loci (QTL) analysis of yield influencing traits was carried out in Brassica juncea (AABB) using a doubled haploid (DH) mapping population of 123 lines derived from a cross between Varuna (a line representing the Indian gene pool) and Heera (representing the east European gene pool) to identify potentially useful alleles from both the parents. The existing AFLP based map of B. juncea was further saturated with RFLP and SSR markers which led to the identification of the linkage groups belonging to the A (B. rapa) and B (B. nigra) genome components of B. juncea. For QTL dissection, the DH lines were evaluated at three different environments and phenotyped for 12 quantitative traits. A total of 65 QTL spread over 13 linkage groups (LG) were identified from the three environments. QTL analysis showed that the A genome has contributed more than the B genome to productivity (68% of the total QTL detected) suggesting a more prominent role of the A genome towards domestication of this crop. The east European line, Heera, carried favorable alleles for 42% of the detected QTL and the remaining 58% were in the Indian gene pool line, Varuna. We observed clustering of major QTL in a few linkage groups, particularly in J7 and J10 of the A genome, with QTL of different traits having agronomically antagonistic allelic effects co-mapping to the same genetic interval. QTL analysis also identified some well-separated QTL which could be readily transferred between the two pools. Based on the QTL analysis, we propose that improvement in yield could be achieved more readily by heterosis breeding rather than by pure line breeding. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
7.
For the transfer of genes from B. tournefortii (TT) to the allotetraploid oilseed brassicas, B. juncea AABB, B. carinata BBCC and B. napus AACC, B. tournefortii was first crossed with the three basic diploid species, B. campestris (AA), B. nigra (BE) and B. oleracea (CC), to produce the allodiploids TA, TB and TC. These were tetraploidized by colchicine treatment to produce the allotetraploids TTAA, TTBB and TTCC, which were further crossed with B. juncea and B. napus to produce three-genome hybrids with substitution-type genomic configurations: TACC, TBAA and TCAA. These hybrids along with another hybrid TCBB produced earlier, the three allodiploids, their allotetraploids and the four diploid parent species were studied for their male meiotic behaviour. The diploid parent and the allotetraploids (TTAA, TTBB and TTCC) showed regular meiosis although the pollen viability was generally low in the allotetraploids. In the allodiploids (TA, TB and TC) only some end-to-end associations were observed without any clearly discernible chiasmata or exchange points. Chromosomes involved in end-to-end associations were randomly distributed at the metaphase/anaphase-I stages. In contrast, the three-genome hybrids (TACC, TBAA, TCAA and TCBB) showed normal bivalents whose number exceeded the expected bivalent values. Bivalents arising out of homoeologous pairing were indistinguishable from normal pairs by their disjunction pattern but could be distinguished on the basis of the heteromorphy of the homoeologous chromosomes. The three-genome hybrids could be backcrossed to allotetraploid oilseed brassicas as they had some fertility. In contrast, the allodiploids could neither be selfed nor back-crossed. On the basis of their meiotic stability, in terms of more pronounced homoeologous pairing and fertility for backcrossing, the three-genome configurations provide the best possible situation for the introgression of alien genes from the secondary gene pool to the allotetraploid oilseed crops B. juncea, B. napus and B. carinata.  相似文献   
8.
Immune prophylaxis and treatment of transplanted tissue rejection act indiscriminately, risking serious infections and malignancies. Although animal data suggest that cellular immune responses causing rejection may be rather narrow and predictable based on genetic background, there are only limited data regarding the clonal breadth of anti-donor responses in humans after allogeneic organ transplantation. We evaluated the graft-infiltrating CD8+ T lymphocytes in skin punch biopsies of a transplanted hand over 178 days. Profiling of T cell receptor (TCR) variable gene usage and size distribution of the infiltrating cells revealed marked skewing of the TCR repertoire indicating oligoclonality, but relatively normal distributions in the blood. Although sampling limitation prevented complete assessment of the TCR repertoire, sequencing further identified 11 TCR clonal expansions that persisted through varying degrees of clinical rejection and immunosuppressive therapy. These 11 clones were limited to three TCR beta chain variable (BV) gene families. Overall, these data indicate significant oligoclonality and likely restricted BV gene usage of alloreactive CD8+ T lymphocytes, and suggest that changes in rejection status are more due to varying regulation of their activity or number rather than shifts in the clonal populations in the transplanted organ. Given that controlled animal models produce predictable BV usage in T lymphocytes mediating rejection, understanding the determinants of TCR gene usage associated with rejection in humans may have application in specifically targeted immunotherapy.  相似文献   
9.
The effect of Sargassum polycystum crude extract on lipid metabolism was examined against acetaminophen-induced (800 mg/kg body wt., intraperitoneally) hyperlipidemia during toxic hepatitis in experimental rats. The animals intoxicated with acetaminophen showed significant elevation in the levels of cholesterol, triglycerides and free fatty acid in both serum and liver tissue. The levels of tissue total lipids and serum LDL-cholesterol were also elevated with depleted levels of serum HDL-cholesterol and tissue phospholipid. The acetaminophen-induced animals showed significant alterations in the activities of lipid metabolizing enzymes serum lecithin cholesterol acyl transferase (LCAT) and hepatic triglyceride lipase (HTGL). The levels of liver tissue fatty acids (saturated, mono and polyunsaturated) such as palmitic acid, stearic acid, oleic acid, linoleic acid, arachidonic acid and linolenic acid monitored by gas chromatography were considerably altered in acetaminophen intoxicated animals when compared with control animals. The prior oral administration of Sargassum polycystum (200 mg/kg body wt./day for a period of 15 days) crude extract showed considerable prevention in the severe disturbances of lipid profile and metabolizing enzymes triggered by acetaminophen during hepatic injury. Liver histology also showed convincing supportive evidence regarding their protective nature against fatty changes induced during acetaminophen intoxication. Thus the present study indicates that the protective nature of Sargassum polycystum extract may be due to the presence of active compounds possessing antilipemic property against acetaminophen challenge. (Mol Cell Biochem 276: 89–96, 2005)  相似文献   
10.
Brain edema and associated increased intracranial pressure are major consequences of traumatic brain injury (TBI). An important early component of the edema associated with TBI is astrocyte swelling (cytotoxic edema). Mechanisms for such swelling, however, are poorly understood. Ion channels/transporters/exchangers play a major role in cell volume regulation, and a disturbance in one or more of these systems may result in cell swelling. To examine potential mechanisms in TBI-mediated brain edema, we employed a fluid percussion model of in vitro barotrauma and examined the role of the ion transporter Na(+)-K(+)-2Cl(-)-cotransporter 1 (NKCC1) in trauma-induced astrocyte swelling as this transporter has been strongly implicated in the mechanism of cell swelling in various neurological conditions. Cultures exposed to trauma (3, 4, 5 atm pressure) caused a significant increase in NKCC1 activity (21%, 42%, 110%, respectively) at 3 h. At 5 atm pressure, trauma significantly increased NKCC1 activity at 1 h and it remained increased for up to 3 h. Trauma also increased the phosphorylation (activation) of NKCC1 at 1 and 3 h. Inhibition of MAPKs and oxidative/nitrosative stress diminished the trauma-induced NKCC1 phosphorylation as well as its activity. Bumetanide, an inhibitor of NKCC1, significantly reduced the trauma-induced astrocyte swelling (61%). Silencing NKCC1 with siRNA led to a reduction in trauma-induced NKCC1 activity as well as in cell swelling. These findings demonstrate the critical involvement of NKCC1 in the astrocyte swelling following in vitro trauma, and suggest that blocking NKCC1 activity may represent a useful therapeutic strategy for the cytotoxic brain edema associated with the early phase of TBI.  相似文献   
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