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991.
992.
Decrease of the insulin‐like growth factor‐1 bioavailability in spontaneously hypertensive rats with erectile dysfunction 下载免费PDF全文
We investigated the role of insulin‐like growth factor‐1 (IGF‐1) in spontaneously hypertensive rats with erectile dysfunction. Firstly, we evaluated intracavernous pressure. The bioavailability of IGF‐1 at both mRNA and protein levels were measured by quantitative real‐time PCR and Western blot respectively. Then, cavernous cyclic guanosine monophosphate concentrations were detected by enzyme‐linked immunosorbent assay. The cavernosal pressure was significantly decreased in the hypertensive and the propranolol treatment groups compared to the normal control group (P < 0.01). Cavernous IGF‐1 bioavailability and the concentrations of cavernous cyclic guanosine monophosphate were both significantly decreased in the hypertensive and the propranolol treatment groups compared to the normal control group (P < 0.01). This study suggests that an obvious decrease in cavernous IGF‐1 levels might play an important role in spontaneously hypertensive rats with erectile dysfunction. 相似文献
993.
Targeting formyl peptide receptor 1 of activated macrophages to monitor inflammation of experimental osteoarthritis in rat 下载免费PDF全文
Xinlin Yang Mahendra D. Chordia Xuejun Du John L. Graves Yi Zhang Yong‐Sang Park Yongfei Guo Dongfeng Pan Quanjun Cui 《Journal of orthopaedic research》2016,34(9):1529-1538
Macrophages play a crucial role in the pathogenesis of osteoarthritis (OA). In this study, the feasibility of a formyl peptide receptor 1 (Fpr1)‐targeting peptide probe cFLFLF‐PEG‐64Cu via positron emission tomography (PET) imaging was investigated for detection of macrophage activity during development of OA. Monoiodoacetate (MIA) was intraarticularly injected into the knee joint of Sprague–Dawley rats to induce OA. Five days later, cFLFLF‐PEG‐64Cu (~7,400 kBq/rat) was injected into the tail vein and microPET/CT imaging was performed to assess the OA inflammation by detecting infiltration of macrophages by Fpr1 expression. In addition, a murine macrophage cell line RAW264.7 and two fluorescent probes cFLFLF‐PEG‐cyanine 7 (cFLFLF‐PEG‐Cy7) and cFLFLF‐PEG‐cyanine 5 (cFLFLF‐PEG‐Cy5) were used to define the binding specificity of the peptide to macrophages. It was found with the MIA model that the maximal standard uptake values (SUVmax) for right (MIA treated) and left (control) knees were 17.96 ± 5.45 and 3.00 ± 1.40, respectively. Histological evaluation of cryomicrotome sections showed that Fpr1 expression, cFLFLF‐PEG‐Cy5 binding, and tartrate‐resistant acid phosphatase activity were elevated in the injured synovial membranes. The in vitro experiments demonstrated that both fluorescent peptide probes could bind specifically to RAW264.7 cells, which was blocked by cFLFLF but not by the scramble peptide. The findings highlighted the use of cFLFLF‐PEG‐64Cu/PET as an effective method potentially applied for detection and treatment evaluation of OA. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1529–1538, 2016. 相似文献
994.
Cartilage degeneration and excessive subchondral bone formation in spontaneous osteoarthritis involves altered TGF‐β signaling 下载免费PDF全文
Weiwei Zhao Ting Wang Qiang Luo Yan Chen Victor Y. L. Leung Chunyi Wen Mohammed F. Shah Haobo Pan KwongYuen Chiu Xu Cao William W. Lu 《Journal of orthopaedic research》2016,34(5):763-770
Transforming growth factor‐β (TGF‐β) has been demonstrated as a potential therapeutic target in osteoarthritis. However, beneficial effects of TGF‐β supplement and inhibition have both been reported, suggesting characterization of the spatiotemporal distribution of TGF‐β during the whole time course of osteoarthritis is important. To investigate the activity of TGF‐β in osteoarthritis progression, we collected knee joints from Dunkin–Hartley (DH) guinea pigs at 3, 6, 9, and 12‐month old (n = 8), which develop spontaneous osteoarthritis in a manner extraordinarily similar to humans. Via histology and micro‐computed tomography (CT) analysis, we found that the joints exhibited gradual cartilage degeneration, subchondral plate sclerosis, and elevated bone remodeling during aging. The degenerating cartilage showed a progressive switch of the expression of phosphorylated Smad2/3 to Smad1/5/8, suggesting dual roles of TGF‐β/Smad signaling during chondrocyte terminal differentiation in osteoarthritis progression. In subchondral bone, we found that the locations and age‐related changes of osterix+ osteoprogenitors were in parallel with active TGF‐β, which implied the excessive osteogenesis may link to the activity of TGF‐β. Our study, therefore, suggests an association of cartilage degeneration and excessive bone remodeling with altered TGF‐β signaling in osteoarthritis progression of DH guinea pigs. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:763–770, 2016. 相似文献
995.
Multi‐lineage differentiation and angiogenesis potentials of pigmented villonodular synovitis derived mesenchymal stem cells ‐ pathological implication 下载免费PDF全文
En‐Rung Chiang Hsiao‐Li Ma Jung‐Pan Wang Chien‐Lin Liu Tain‐Hsiung Chen Shih‐Chieh Hung 《Journal of orthopaedic research》2016,34(3):395-403
Pigmented villonodular synovitis (PVNS) is a benign tissue proliferation characterized by its hyper‐vascularity within the lesion. The true etiology and cell source of this disease entity still remain unclear. Mesenchymal stem cells (MSCs) exist in various tissues of human body. However, it has not been clarified whether MSCs could be isolated from tissue of PVNS. Here, we isolated MSCs from PVNS (PVNS‐SCs), and by comparing to the MSCs from normal synovium (Syn‐SCs) of the same individual, we investigated whether PVNS‐SCs differed in the capacity for multi‐differentiation and inducing angiogenesis. We first demonstrated that PVNS‐SCs existed in the lesion of PVNS of three individuals. Moreover, we showed PVNS‐SCs had better osteogenic differentiation potential than Syn‐SCs, whereas Syn‐SCs had better capacity for adipogenic and chondrogenic differentiation. By genome–wide analysis of gene expression profile using a complementary DNA microarray and comparing to Syn‐SCs, we identified in PVNS‐SCs a distinct gene expression profile characterized by up‐regulation of genes involved in angiogenesis. In vitro and in vivo studies further confirmed that PVNS‐SCs had better capacities for promoting angiogenesis. In summary, the identification of PVNS‐SCs in PVNS tissue and their distinct angiogenic potential may help elucidate the underlying etiology of this disease. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:395–403, 2016. 相似文献
996.
Quantity of lymph nodes correlates with improvement in lymphatic drainage in treatment of hind limb lymphedema with lymph node flap transfer in rats 下载免费PDF全文
997.
Jiatong Hou Ping Yu Huijuan Zhu Hui Pan Naishi Li Hongbo Yang 《Gynecological endocrinology》2016,32(1):9-13
The effects of maternal hypothyroidism on neonatal outcomes were not definitely confirmed. We conduct a systematic review of the literatures on the impact of maternal hypothyroidism on neonatal outcomes. We searched Pubmed, Embase and the Cochrane Controlled Trials Register databases complemented by manual searches in article references without language restrictions published from 1946 to April 2015. Nine trials are included. For preterm birth in pregnancies of hypothyroidism women, there is an increased tendency (RR 1.18; 95% CI 0.99 to 1.40; p?=?0.06). The same result is seen relating to the low birth weight (RR 1.31; 95% CI 1.00 to 1.72; p?=?0.05). Regarding small for gestational age there is no significant increase. Children who were born from mothers with hypothyroidism during pregnancy have increased birth weight (MD 32.35, 95% CI 7.46 to 57.24; p?=?0.01). The impact of maternal hypothyroidism shows a trend of reduced risk of large for gestational age (RR 1.17; 95% CI 0.99 to 1.38; p?=?0.06). Our review suggests that mothers with hypothyroidism during pregnancy are more likely to give birth to children with higher birth weight or LGA, and L-T4 supplementation should be recommended. The risk of preterm birth and low birth weight also tends to be higher in children with hypothyroidism mothers. 相似文献
998.
Yinbing?Pan Xiaodi?Sun Lai?Jiang Liang?Hu Hong?Kong Yuan?Han Cheng?Qian Chao?Song Yanning?Qian Wentao?LiuEmail author 《Journal of neuroinflammation》2016,13(1):294
Background
Tolerance seriously impedes the application of morphine in clinical medicine. Thus, it is necessary to investigate the exact mechanisms and efficient treatment. Microglial activation and neuroinflammation in the spinal cord are thought to play pivotal roles on the genesis and maintaining of morphine tolerance. Activation of adenosine monophosphate-activated kinase (AMPK) has been associated with the inhibition of inflammatory nociception. Metformin, a biguanide class of antidiabetic drugs and activator of AMPK, has a potential anti-inflammatory effect. The present study evaluated the effects and potential mechanisms of metformin in inhibiting microglial activation and alleviating the antinociceptive tolerance of morphine.Methods
The microglial cell line BV-2 cells and mouse brain-derived endothelial cell line bEnd3 cells were used. Cytokine expression was measured using quantitative polymerase chain reaction. Cell signaling was assayed by western blot and immunohistochemistry. The antinociception and morphine tolerance were assessed in CD-1 mice using tail-flick tests.Results
We found that morphine-activated BV-2 cells, including the upregulation of p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation, pro-inflammatory cytokines, and Toll-like receptor-4 (TLR-4) mRNA expression, which was inhibited by metformin. Metformin suppressed morphine-induced BV-2 cells activation through increasing AMPK phosphorylation, which was reversed by the AMPK inhibitor compound C. Additionally, in BV-2 cells, morphine did not affect the cell viability and the mRNA expression of anti-inflammatory cytokines. In bEnd3 cells, morphine did not affect the mRNA expression of interleukin-1β (IL-1β), but increased IL-6 and tumor necrosis factor-α (TNF-α) mRNA expression; the effect was inhibited by metformin. Morphine also did not affect the mRNA expression of TLR-4 and chemokine ligand 2 (CCL2). Furthermore, systemic administration of metformin significantly blocked morphine-induced microglial activation in the spinal cord and then attenuated the development of chronic morphine tolerance in mice.Conclusions
Metformin significantly attenuated morphine antinociceptive tolerance by suppressing morphine-induced microglial activation through increasing AMPK phosphorylation.999.
HLA‐A,HLA‐B,HLA‐DRB1 allele and haplotype frequencies of 14 529 Chinese Han bone marrow donors living in Dalian,China 下载免费PDF全文
L. N. Shao S. T. Zhang W. J. Yu S. H. Zhou Y. Duan L. Z. Pan N. Wang Y. Hu 《International journal of immunogenetics》2016,43(2):79-85
We investigated the allele and haplotype frequencies of HLA‐A, HLA‐B and HLA‐DRB1 loci in Dalian Chinese Han population using blood samples of unrelated marrow donors who live in Dalian. The genetic relationship between Dalian and different regions worldwide was further explored based on HLA status of different populations. A total of 14 529 samples were genotyped at 2‐digit level only by sequence‐specific oligonucleotide and sequence‐based typing methods. Allele frequencies of HLA‐A, HLA‐B and HLA‐DRB1 were calculated by the direct counting method. Haplotype frequencies and linkage disequilibrium (LD) values were calculated by the maximum likelihood method. FST values were calculated by allele frequency data of each locus. Phylogeny tree of Nei's DA genetic distances was constructed by the UPGMA method. HLA‐A*02 was the most frequent allele at HLA‐A locus followed by A*11 and A*24. Alleles at HLA‐B locus ranked in decreasing order by frequency were B*40, B*15 and B*13. The three highest frequency alleles were DRB1*15, DRB1*09 and DRB1*12 at HLA‐DRB1 locus. A*30‐B*13‐DRB1*07 was the most frequent three‐locus haplotype. For the population relationships, Dalian had a relative close genetic relationship with Liaoning and Yantai‐Weihai and a relative distant genetic relationship with Australia. The information obtained in this study may provide useful information for anthropological studies, for disease‐association studies and helping bone marrow transplantation patients to search HLA‐matched donors. 相似文献
1000.
Purpose: Traumatic optic neuropathy (TON) is a serious complication of head trauma with the incidence
rate of 0.5%e5%. The aim of this study was to investigate the therapeutic efficacy of endoscopic
decompression of the optic canal for optic nerve injuries.
Methods: In this study, 11 patients treated in our hospital from January 2009 to January 2015 with the visual loss resulting from TON were retrospectively reviewed for preoperative vision, visual evoked potential (VEP) scan, surgical approach, postoperative visual acuity, complications, and follow-up results.
Results: All these patients received endoscopic decompression of the optic canal. At the 3-month followup, the visual acuity improvement rate of the 11 patients was 45.5%. The vision acuity of 2 cases improved from hand movement to 0.08 and 0.3 after operation. Another patient''s vision acuity returned to 0.05 compared to light sensation preoperatively. Two cases had finger counting before surgery but they had a vision acuity of 0.4 and light sensation respectively after surgery. However, the other 6 cases'' vision did not improve after surgery.
Conclusion: Endoscopic decompression of the optic canal is an effective way to cure TON. VEP could be
used as an important reference for preoperative and prognosis evaluation. Operative time after trauma is only a relative condition that may affect the therapeutic effect of optic canal decompression. Poor results of this procedure may be related to the severity of the optic nerve injury. 相似文献