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961.

Background

Hepatitis C virus (HCV) infection is the main cause of chronic liver disease and to date there has been no vaccine development to prevent this infection. Among non-structural HCV proteins, NS3 protein is an excellent goal for a therapeutic vaccine, due to its large size and less variation in conserved regions. The immunogenic properties of heat shock proteins (HSPs) for instance GP96 have prompted investigations into their function as strong adjuvant to improve innate and adaptive immunity.

Objectives

The aim of this study was to examine additive effects of recombinant GP96 (rGP96) fragments accompanied by rNS3 on expression levels of α5integrin and pro-inflammatory cytokines, IL-12 and TNFα, in Antigen Presenting Cells (APCs).

Materials and Methods

Recombinant viral proteins (rNS3 and rRGD-NS3), N-terminal and C-terminal fragments of GP96 were produced and purified from E. coli in order to treat the cells; mouse spleen Dendritic Cells (DCs) and THP-1 macrophages.

Results

Our results showed that rNT-GP96 alone significantly increases the expression level of IL-12, TNFα and α5integrin in THP-1 macrophages and DCs, while IL-12 and TNFα expression levels were unaffected by either rNS3 or rRGD-NS3. Interestingly, the co-addition of these recombinant proteins with rNT-GP96 increased IL-12, TNFα and α5integrin expression. Pearson Correlation showed a direct association between α5integrin with IL-12 and TNF-α expression.

Conclusions

we have highlighted the role of rNS3 plus rNT-GP96 mediated by α5integrin in producing IL-12 and TNFα. It can be suggested that rNT-GP96 could enhance immunity characteristic of rNS3 protein via production of pro-inflammatory cytokines.  相似文献   
962.
963.
964.
There are adverse physiologic effects of pain in neonates, and effective pain management must be an essential aspect of neonatal care. In this study we assessed the effect of a nonmaternal familiar scent on the neonatal pain responses. This study included 135 neonates randomly assigned to one of three groups. During arterial puncture, one group was exposed to a vanillin scent on a gauze pad held next to their nose. They were familiarized with it the night before blood sampling by a scented gauze pad placed in the incubator next to their head for an average duration of 8.65 hours. The second group was not familiarized with the scent but was exposed to it during the procedure. The third group was neither familiarized nor exposed to the scent. The duration of crying in the familiar scent group was significantly lower than in the two other groups. Comparison of the physiologic parameters showed less variation in oxygen saturation level during arterial puncture in the familiar scent group. In this study, a familiar scent could reduce crying and oxygen consumption during arterial puncture.  相似文献   
965.
Juvenile hormone (JH) coordinates timing of female reproductive maturation in most insects. In Drosophila melanogaster, JH plays roles in both mating and egg maturation. However, very little is known about the molecular pathways associated with mating. Our behavioral analysis of females genetically lacking the corpora allata, the glands that produce JH, showed that they were courted less by males and mated later than control females. Application of the JH mimic, methoprene, to the allatectomized females just after eclosion rescued both the male courtship and the mating delay. Our studies of the null mutants of the JH receptors, Methoprene tolerant (Met) and germ cell-expressed (gce), showed that lack of Met in Met27 females delayed the onset of mating, whereas lack of Gce had little effect. The Met27 females were shown to be more attractive but less behaviorally receptive to copulation attempts. The behavioral but not the attractiveness phenotype was rescued by the Met genomic transgene. Analysis of the female cuticular hydrocarbon profiles showed that corpora allata ablation caused a delay in production of the major female-specific sex pheromones (the 7,11-C27 and -C29 dienes) and a change in the cuticular hydrocarbon blend. In the Met27 null mutant, by 48 h, the major C27 diene was greatly increased relative to wild type. In contrast, the gce2.5k null mutant females were courted similarly to control females despite changes in certain cuticular hydrocarbons. Our findings indicate that JH acts primarily via Met to modulate the timing of onset of female sex pheromone production and mating.All aspects of reproductive maturation in animals including gonad development, pheromone production for communication between the sexes, and mating behavior need to be precisely timed and coordinated to ensure reproductive success, and regulatory hormones are the key to this timing and coordination (1, 2). In most female insects, the sesquiterpenoid juvenile hormone (JH) regulates and coordinates reproductive maturation of the ovaries (2, 3) and often sex pheromone synthesis and mating behavior (4, 5). In Drosophila melanogaster, females are unreceptive to male courtship attempts just after eclosion, but by day 2, most become receptive and mate (6, 7). Implantation of JH-secreting corpora allata (CA) (6) just before eclosion or application of methoprene (8), a JH mimic (JHM), caused females to mate precociously. Decreased JH in the apterous mutant (9) or after treatment of females with precocene, a compound cytotoxic for the CA (10), reduced female mating. These findings suggest that JH may play a role in the maturation of female receptivity in D. melanogaster.The switch from an unreceptive to a receptive state requires coordination of neural activity critical for female mating behaviors with production of sex pheromones that attract the male (1113). The Drosophila sex pheromones are a subgroup of the cuticular hydrocarbons (CHC) that mediate chemical communication for both sex and species recognition (see refs. 14 and 15 for reviews). In D. melanogaster, two CHCs, (Z,Z)-7,11-C27:2 (C27) and (Z,Z)-7,11-C29:2 (C29) dienes, are female-specific; these dienes are known to play a role in mate choice preference and the onset of male courtship (1518). Overexpression of the JH esterase-binding protein DmP29 after eclosion, which is thought to reduce the JH titer, caused a reduction in the synthesis of these female-specific dienes (19). The role of JH in the biosynthesis of these CHCs is unknown.In D. melanogaster, there are two basic helix–loop–helix proteins encoded by the paralogous genes, Methoprene-tolerant (Met) and germ cell-expressed (gce), which act as JH receptors in both metamorphosis and reproductive maturation (2022). Loss of function of both receptor genes is necessary to mimic the effect of genetic ablation of the CA in larvae, which causes prepupal lethality (2325). In the adult, loss of Met causes both delayed and reduced fecundity, whereas loss of gce has only a slight effect on ovarian maturation (25). To elucidate the molecular mechanisms underlying JH’s role in the onset of mating in D. melanogaster females, we have genetically ablated the CA in the developing adult and found that the onset of mating behavior was delayed, and this delay could be rescued by JH. This action of JH was dependent only on the Met receptor and was partly due to modulation of sex pheromone production.  相似文献   
966.
A goal of regenerative medicine is to identify cardiovascular progenitors from human ES cells (hESCs) that can functionally integrate into the human heart. Previous studies to evaluate the developmental potential of candidate hESC-derived progenitors have delivered these cells into murine and porcine cardiac tissue, with inconclusive evidence regarding the capacity of these human cells to physiologically engraft in xenotransplantation assays. Further, the potential of hESC-derived cardiovascular lineage cells to functionally couple to human myocardium remains untested and unknown. Here, we have prospectively identified a population of hESC-derived ROR2+/CD13+/KDR+/PDGFRα+ cells that give rise to cardiomyocytes, endothelial cells, and vascular smooth muscle cells in vitro at a clonal level. We observed rare clusters of ROR2+ cells and diffuse expression of KDR and PDGFRα in first-trimester human fetal hearts. We then developed an in vivo transplantation model by transplanting second-trimester human fetal heart tissues s.c. into the ear pinna of a SCID mouse. ROR2+/CD13+/KDR+/PDGFRα+ cells were delivered into these functioning fetal heart tissues: in contrast to traditional murine heart models for cell transplantation, we show structural and functional integration of hESC-derived cardiovascular progenitors into human heart.  相似文献   
967.
ObjectiveWhile a Mediterranean dietary pattern (MedDiet) has been associated with favorable changes in several features of metabolic syndrome (MetS), its impact on plasma adipokine concentrations remains largely unknown. The objective of this study was to determine the impact of the MedDiet consumed under controlled feeding conditions, without (? WL) and with weight loss (+ WL), on plasma adipokine concentrations in adult men with MetS (NCEP-ATP III).Materials/MethodsThe diet of 26 men with MetS (age 24 to 62 yrs) was first standardized to a North American control diet for 5 weeks. Participants then consumed a pre-determined MedDiet for 5 weeks. Both diets were consumed under weight-maintaining isoenergetic feeding conditions. Participants then underwent a 20-week free-living caloric restriction period, after which they consumed the MedDiet again in weight stabilizing, isoenergetic feeding conditions.ResultsBody weight was reduced by 10.2% ± 2.9% and waist circumference by 8.6 ± 3.3 cm after the weight loss period and stabilization on MedDiet (P < 0.001). MedDiet ? WL had no impact on plasma concentrations of leptin, plasminogen activator inhibitor-1, resistin, visfatin, acylation stimulating protein and adiponectin. MedDiet + WL reduced plasma leptin concentrations (P < 0.01) and increased plasma adiponectin concentrations (P < 0.05) compared with the control diet and MedDiet ? WL.ConclusionData from this nutritionally controlled study suggest that short-term consumption of MedDiet has little effect on the concentrations of many adipokines in the absence of weight loss.  相似文献   
968.
Hb D-Los Angeles is characterized by the substitution of glutamine for glutamic acid at position 121 of the β-globin chain. The present investigation is the first study on the β-globin gene haplotypes associated with β-D-Los Angeles in Western Iran. Thirty two individuals from 11 unrelated families from Western Iran were studied. The Hb D-Los Angeles status of all cases was confirmed using polymerase chain reaction (PCR) followed by digestion with EcoRI. The haplotype of the β‐globin gene cluster was determined by a PCR-RFLP (restriction fragment length polymorphism) procedure. The haplotype background of the βA chromosomes was also determined in 35 normal subjects from the same geographic region. The β-globin gene haplotype analysis demonstrated that all β-D-Los Angeles genes (23 genes) were in linkage disequilibrium with haplotype I [+????++]. Among the 70 βA chromosomes, 30 chromosomes (42.9%) were associated with haplotype I. The present study indicates the unicentric origin of the β-D-Los Angeles gene in Western Iran. It seems that this mutation may have occurred at the same chromosomal background common in the local population.  相似文献   
969.
The role of reduced intensity allogeneic stem cell transplantation for the treatment of relapsed/refractory Hodgkin’s lymphoma remains controversial. We retrospectively analyzed 191 patients who underwent reduced intensity allogeneic stem cell transplantation between 1998 and 2008 for relapsed or refractory Hodgkin’s lymphoma and whose data were reported to the French registry. The median follow-up was 36 months. The estimated 3-year overall survival rate, progression-free survival rate, cumulative incidence of relapse and cumulative incidence of non-relapse mortality were 63%, 39%, 46%, and 16%, respectively. There was no difference in outcome between patients in complete response and in partial response at the time of transplantation with regards to overall survival (70% versus 74%, no significant difference) and progression-free survival (51% versus 42%, no significant difference). Patients with chemoresistant disease had a shorter overall survival (39% at 3 years; P=0.0003) and progression-free survival (18% at 3 years; P=0.001) than patients in complete remission. The use of umbilical cord blood as the source of stem cells was associated with a poor outcome with an increased risk of death with a hazard ratio of 3.49 (95% confidence interval: 1.26 to 9.63; P=0.016). The use of peripheral blood was associated with a better outcome for patients who where alive 1 year after transplantation with a hazard ratio of 0.38 (95% confidence interval: 0.17 to 0.83; P=0.016). Disease status at transplantation remains the most important risk factor for outcome. Our data suggest that the use of peripheral blood should be preferred whereas umbilical cord blood should be used with caution.  相似文献   
970.

Background

Inappropriate diagnosis and treatment of pain, agitation, and delirium (PAD) in intensive care settings results in poor patient outcomes. We designed and used a protocol for systematic assessment and management of PAD by the nurses to improve clinical intensive care unit (ICU) outcomes.

Materials and Methods

A total of 201 patients admitted to 2 mixed medical-surgical ICUs were randomly allocated to protocol and control groups. A multidisciplinary team approved the protocol. Pain was assessed by Numerical Rating Scale and Behavioural Pain Scale, agitation by Richmond Agitation Sedation Scale, and delirium by Confusion Assessment Method in ICU. The Persian version of the scales was prepared and tested for validity, reliability, and feasibility in a preliminary study. The patients in the protocol group were managed pharmacologically according to the protocol, whereas those in the control group were managed according to the ICU routine.

Results

The median (interquartile range) for the duration of mechanical ventilation in the protocol and control groups was 19 (9.3-67.8) and 40 (0-217) hours, respectively (P = .038). The median (interquartile range) length of ICU stay was 97 (54.5-189) hours in the protocol group vs 170 (80-408) hours in the control group (P < .001). The mortality rate in the protocol group was significantly reduced from 23.8% to 12.5% (P = .046).

Conclusion

The current randomized trial provided evidence for a substantial reduction in the duration of need to ventilatory support, length of ICU stay, and mortality rates in ICU-admitted patients through protocol-directed management of PAD.  相似文献   
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