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51.
The 37-kDa laminin receptor precursor/67-kDa laminin receptor (LRP/LR, also known as ribosomal protein SA, RPSA) has been reported to be involved in cancer development and prion internalization. Previous studies have shown that the LRP/LR is expressed in a wide variety of tissues. In particular, expression of LRP/LR mRNA may be closely related to the degree of PrPSc propagation. This study presents a detailed investigation of the LRP/LR mRNA expression levels in eleven normal ovine tissues. Using real-time quantitative PCR, the highest LRP/LR expression was found in neocortex (p < 0.05). Slightly lower levels were found in the heart and obex. Intermediate levels were seen in hippocampus, cerebellum, spleen, thalamus, mesenteric lymph node, and the lowest levels were present in liver, kidney, and lung. In general, the LRP/LR mRNA levels were much higher in neuronal tissues than in peripheral tissues. The observation that differences in LRP/LR mRNA expression levels are consistent with the corresponding variation in PrPSc accumulation suggests that the 37-kDa/67-kDa laminin receptor may be involved in the regulation of PrPSc propagation.  相似文献   
52.
Hemodynamic instability is a common condition during extra-cranial carotid angioplasty and stenting (CAS). We evaluated the safety and efficacy of prophylactic placement of temporary cardiac pacemaker during extra-cranial CAS for the prevention of hemodynamic instability. For this, forty-seven carotid artery stents were deployed in 41 high-risk patients. Temporary transvenous cardiac pacemakers were inserted before CAS procedure. The pacers were set to capture a heart rate <60 bpm. Clinical symptoms, blood pressure, heart rate, and pacing activation were monitored and data were collected. We found that pacing occurred in 25 carotid lesions during balloon predilatation; pacemakers were activated transiently in 25 patients. The longest pacing continued for 1 day. Among cases with pacemaker activation, 1 patient developed post-procedural symptomatic hypotension that lasted for 4 days. No related complications were observed. It was, therefore, concluded that pacing was technically effective in producing electrical ventricular responses and was hemodynamically effective in 25 carotid lesions which underwent balloon predilatation. The prophylactic use of a temporary transvenous cardiac pacemaker during CAS was rapid and effective in controlling peri-operative hemodynamic instability and preventing stroke and other complications. The prophylactic use of temporary pacemaker is particularly recommended for patients at high risk for developing hemodynamic instability.  相似文献   
53.
Caenorhabditis elegans is a leading model organism for studying the basic mechanisms of aging. Progress has been limited, however, by the lack of an automated system for quantitative analysis of longevity and mean lifespan. To address this barrier, we developed ‘WormFarm’, an integrated microfluidic device for culturing nematodes. Cohorts of 30–50 animals are maintained throughout their lifespan in each of eight separate chambers on a single WormFarm polydimethylsiloxane chip. Design features allow for automated removal of progeny and efficient control of environmental conditions. In addition, we have developed computational algorithms for automated analysis of video footage to quantitate survival and other phenotypes, such as body size and motility. As proof‐of‐principle, we show here that WormFarm successfully recapitulates survival data obtained from a standard plate‐based assay for both RNAi‐mediated and dietary‐induced changes in lifespan. Further, using a fluorescent reporter in conjunction with WormFarm, we report an age‐associated decrease in fluorescent intensity of GFP in transgenic worms expressing GFP tagged with a mitochondrial import signal under the control of the myo‐3 promoter. This marker may therefore serve as a useful biomarker of biological age and aging rate.  相似文献   
54.

Introduction

Osteoarthritis (OA) is a degenerative joint disease affecting a large population of people. The mechanism of this highly prevalent disease is not fully understood. Currently there is no effective disease-modifying treatment for OA. The purpose of this study was two-fold: 1) to investigate the role of MMP13 in the development of OA; and 2) to evaluate the efficacy of the MMP13 inhibitor CL82198 as a pharmacologic treatment for preventing OA progression.

Methods

To investigate the role of the endogenous Mmp13 gene in OA development, tamoxifen was administered to two-week-old Col2CreER;Mmp13fx/fx (Mmp13Col2ER) and Cre-negative control mice for five days. OA was induced by meniscal-ligamentous injury (MLI) when the mice were 10 weeks old and MLI or sham-operated joints were harvested 4, 8, 12, or 16 weeks after surgery. To evaluate the efficacy of CL82198, MLI surgery was performed on 10-week-old wild type mice. CL82198 or saline was administered to the mice daily beginning immediately after the surgery for up to 16 weeks. The joint tissues collected from both experiments were evaluated by cartilage grading, histology/histomorphometry, immunohistochemistry (IHC), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The ability of CL82198 to inhibit MMP13 activity in vitro was confirmed by ELISA.

Results

The OA progression was decelerated in Mmp13Col2ER mice 8, 12, and 16 weeks post-surgery. Cartilage grading by blinded observers confirmed decreased articular cartilage degeneration in Mmp13Col2ER mice at 8, 12 and 16 weeks compared to Cre-negative mice. Histomorphometric analysis demonstrated that Mmp13Col2ER mice had a higher articular cartilage area and thickness at 12 and 16 weeks post-surgery compared to the control mice. Results of IHC revealed greater type II collagen and proteoglycan expression in Mmp13Col2ER mice. Chondrocyte apoptosis, as determined by TUNEL staining, was higher in control mice compared to Mmp13Col2ER mice. CL82198 inhibited MMP13 activity in conditioned media from vehicle (> 85%) or bone morphogenetic protein 2 (BMP2)-treated (> 90%) primary murine sternal chondrocytes. Intraperitoneal injection of CL82198 decelerated MLI-induced OA progression, increased type II collagen and proteoglycan levels, and inhibited chondrocyte apoptosis compared to saline treatment as determined by OA grading, histology, histomorphometry, IHC, and TUNEL staining, respectively.

Conclusions

Mmp13 is critical for OA progression and pharmacologic inhibition of MMP13 is an effective strategy to decelerate articular cartilage loss in a murine model of injury-induced knee OA.  相似文献   
55.
Choristopsychidae, established by Martynov in 1937 with a single isolated forewing, is a little known extinct family in Mecoptera. Since then, no new members of this enigmatic family have been described. Based on 23 well-preserved specimens with complete body and wings from the Middle Jurassic of northeastern China, we report one new genus and three new species of Choristopsychidae, two new species of the genus Choristopsyche Martynov, 1937: Choristopsyche perfecta sp. n. and Choristopsyche asticta sp. n.; one new species of Paristopsyche gen. n.: Paristopsyche angelineae sp. n.; and re-describe Choristopsyche tenuinervis Martynov, 1937. In addition, we emend the diagnoses of Choristopsychidae and Choristopsyche. Analyzing the forewing length/width ratios of representative species in Mecoptera, we confirm that choristopsychids have the lowest ratio of forewing length/width, meaning broadest forewings. These findings, the first fossil choristopsychids with well-preserved body structure and the first record of Choristopsychidae in China, shed light on the morphology of these taxa and broaden their distribution from Tajikistan to China, while increasing the diversity of Mesozoic Mecoptera in China.  相似文献   
56.
Nodose ganglia are composed of A-, Ah- and C-type neurons. Despite their important roles in regulating visceral afferent function, including cardiovascular, pulmonary, and gastrointestinal homeostasis, information about subtype-specific expression, molecular identity, and function of individual ion transporting proteins is scarce. Although experiments utilizing the sliced ganglion preparation have provided valuable insights into the electrophysiological properties of nodose ganglion neuron subtypes, detailed characterization of their electrical phenotypes will require measurements in isolated cells. One major unresolved problem, however, is the difficulty to unambiguously identify the subtype of isolated nodose ganglion neurons without current-clamp recording, because the magnitude of conduction velocity in the corresponding afferent fiber, a reliable marker to discriminate subtypes in situ, can no longer be determined. Here, we present data supporting the notion that application of an algorithm regarding to microscopic structural characteristics, such as neuron shape evaluated by the ratio between shortest and longest axis, neuron surface characteristics, like membrane roughness, and axon attachment, enables specific and sensitive subtype identification of acutely dissociated rat nodose ganglion neurons, by which the accuracy of identification is further validated by electrophysiological markers and overall positive predictive rates is 89.26% (90.04%, 76.47%, and 98.21% for A-, Ah, and C-type, respectively). This approach should aid in gaining insight into the molecular correlates underlying phenotypic heterogeneity of nodose ganglia. Additionally, several critical points that help for neuron identification and afferent conduction calibration are also discussed.  相似文献   
57.
Normal hematopoiesis is suppressed during the development of leukemia. In the T-ALL leukemia mouse model described in our recent study (Hu X, et al. Blood 2009), the impacts of leukemic environment on normal hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were distinct, in that normal HSCs were preserved in part because of increased mitotic quiescence of HSCs and resulting exhaustion of HPCs proliferation. Stem cell factor (SCF) secreted by leukemic cells in Nalm6 B-ALL model was previously suggested to force normal HSCs/HPCs out of their bone marrow niches and allow leukemic cells to occupy the niches (Colmone A, et al. Science 2008). Here we found that stem cell factor (SCF) expression in PB and BM of T-ALL model was increased, but SCF mRNA and protein levels in normal hematopoietic cells were higher than those in leukemia cells, which suggested that upregulated SCF was mainly contributed by non-leukemic cells in response to the leukemia development. To further elucidate the molecular mechanisms, microarray analysis was conducted on normal HSCs in this model and verified by real-time RT-PCR. The expression of Hes1 and its downstream target p21 were elevated in normal HSCs, whereas their expression showed no significant alteration in HPCs. Interestingly, although overexpression of Hes1 by retroviral infection inhibited the in vitro colony formation of normal hematopoietic cells, in vivo results demonstrated that normal Lin- cells and HSPCs were better preserved when normal Lin- cells with Hes1 overexpression were co-transplanted with T-ALL leukemia cells. Our results suggested that the differential expression of Hes1 between HSCs and HPCs resulted in the distinct responses of these cells to the leukemic condition, and that overexpression of Hes1 could enhance normal HSPCs in the leukemic environment.  相似文献   
58.
Rosiglitazone (RGL), a synthetic agonist for peroxisome proliferator activated receptor γ (PPARγ), exhibits a potent anti-inflammatory activity by attenuating local infiltration of neutrophils and monocytes in the renal interstitium. To evaluate the mechanisms that account for inhibiting inflammatory cells infiltration, we investigated the effect of RGL on chemokines secretion and nuclear factor-kappa B (NF-κB) activation in human renal proximal tubular cells (PTCs). We demonstrated that RGL significantly inhibited lipopolysaccharide (LPS)-induced interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) production in a dose-dependent manner, without appreciable cytotoxicity. Chromatin immunoprecipitation (ChIP) assays clearly revealed that, RGL inhibited p65 binding to IL-8/MCP-1 gene promoters in LPS-stimulated PTCs. Interestingly, further experiments showed RGL reversed LPS-induced nuclear receptor corepressor (NCoR) degradation. In addition, knockdown of protein inhibitor of activated STAT1 (PIAS1), an indispensable small ubiquitin-like modifier (SUMO) ligase, abrogated the effects of RGL on antagonizing LPS-induced IL-8/MCP-1 overexpression and NCoR degradation. These findings suggest that, RGL activates PPARγ SUMOylation, inhibiting NCoR degradation and NF-κB activation in LPS-stimulated PTCs, which in turn decrease chemokines expression. The results unveil a new mechanism triggered by RGL for prevention of tubular inflammatory injury.  相似文献   
59.

Purpose

This study was intended to identify the disease causing genes in a large Chinese family with autosomal dominant retinitis pigmentosa and macular degeneration.

Methods

A genome scan analysis was conducted in this family for disease gene preliminary mapping. Snapshot analysis of selected SNPs for two-point LOD score analysis for candidate gene filter. Candidate gene PRPF31 whole exons'' sequencing was executed to identify mutations.

Results

A novel nonsense mutation caused by an insertion was found in PRPF31 gene. All the 19 RP patients in 1085 family are carrying this heterozygous nonsense mutation. The nonsense mutation is in PRPF31 gene exon9 at chr19:54629961-54629961, inserting nucleotide “A” that generates the coding protein frame shift from p.307 and early termination at p.322 in the snoRNA binding domain (NOP domain).

Conclusion

This report is the first to associate PRPF31 gene''s nonsense mutation and adRP and JMD. Our findings revealed that PRPF31 can lead to different clinical phenotypes in the same family, resulting either in adRP or syndrome of adRP and JMD. We believe our identification of the novel “A” insertion mutation in exon9 at chr19:54629961-54629961 in PRPF31 can provide further genetic evidence for clinical test for adRP and JMD.  相似文献   
60.

Background

In centenarian populations, application of the positive biology approach (examination of positive phenotypes in aging) has revealed that mitochondrial DNA (mtDNA) mutation accumulation may be linked to human longevity; however, the role of guanine nucleotide-binding protein (G protein) abnormalities modulated by G-protein beta-3 (GNB3) and nitrate (NO2) production associated with endothelial nitric oxide synthase (eNOS), commonly appearing in age-related diseases, remains undetermined.

Objective

The association between the mtDNA 5178A/C, mtDNA 10398A/G, GNB3 C825T, and eNOS polymorphisms and longevity in a Uygur population (Xinjiang region, China) were investigated.

Methods

A total of 275 experimental subjects aged ≥100 or with 4 generations currently living were screened for inclusion in the centenarian (>100 years) and nonagenarian groups (90–100 years), and 112 65–70 year old control subjects were selected. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine mtDNA 5178A/C, mtDNA 10398A/G, GNB3 C825T, and eNOS. Associations between polymorphic loci, genotypes, and longevity were analyzed.

Results

165 included subjects (M∶F = 107∶58; mean age = 97±3 years; mean age 100–113 years) were assigned to the centenarian (M∶F = 46/19; n = 65) and nonagenarian groups (M∶F = 61/39; n = 100). Associations between mtDNA C5178A and A10398G polymorphisms with longevity in the centenarian group with mtDNA genotype frequencies 5178A and 10398G were 66.79% and 36.8%.

Conclusions

Applying the overwhelming longevity observed in Uygur populations, these findings demonstrate that mtDNA 5178A/C and 10398A/G, GNB3 C825T, and eNOS polymorphisms are useful as a genetic basis for longevity.  相似文献   
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