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Li X, Ahammed GJ, Zhang YQ, Zhang GQ, Sun ZH, Zhou J, Zhou YH, Xia XJ, Yu JQ, Shi K. Carbon dioxide enrichment alleviates heat stress by improving cellular redox homeostasis through an ABA-independent process in tomato plants. PLANT BIOLOGY (STUTTGART, GERMANY) 2015; 17:81-9. [PMID: 24985337 DOI: 10.1111/plb.12211] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 04/18/2014] [Indexed: 05/18/2023]
Abstract
Plant responses to elevated CO₂ and high temperature are critically regulated through a complex network of phytohormones and redox homeostasis. However, the involvement of abscisic acid (ABA) in plant adaptation to heat stress under elevated CO₂ conditions has not been thoroughly studied. This study investigated the interactive effects of elevated CO₂ (800 μmol·mol(-1) ) and heat stress (42 °C for 24 h) on the endogenous level of ABA and the cellular redox state of two genotypes of tomato with different ABA biosynthesis capacities. Heat stress significantly decreased maximum photochemical efficiency of PSII (Fv/Fm) and leaf water potential, but also increased levels of malondialdehyde (MDA) and electrolyte leakage (EL) in both genotypes. Heat-induced damage was more severe in the ABA-deficient mutant notabilis (not) than in its parental cultivar Ailsa Craig (Ailsa), suggesting that a certain level of endogenous ABA is required to minimise the heat-induced oxidative damage to the photosynthetic apparatus. Irrespective of genotype, the enrichment of CO₂ remarkably stimulated Fv/Fm, MDA and EL in heat-stressed plants towards enhanced tolerance. In addition, elevated CO₂ significantly strengthened the antioxidant capacity of heat-stressed tomato seedlings towards a reduced cellular redox state for a prolonged period, thereby mitigating oxidative stress. However, elevated CO₂ and heat stress did not alter the endogenous level of ABA or the expression of its biosynthetic gene NCED2 in either genotype, indicating that ABA is not involved in elevated CO₂ -induced heat stress alleviation. The results of this study suggest that elevated CO₂ alleviated heat stress through efficient regulation of the cellular redox poise in an ABA-independent manner in tomato plants.
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Xiong XJ, Liu W, Yang XC, Feng B, Zhang YQ, Li SJ, Li XK, Wang J. Ginkgo biloba extract for essential hypertension: a systemic review. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:1131-6. [PMID: 24877716 DOI: 10.1016/j.phymed.2014.04.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 03/20/2014] [Accepted: 04/20/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND Ginkgo biloba extract (GBE), a traditional natural herbal product, is often used in the treatment of essential hypertension (EH) as complementary therapy in China and European countries. AIM To critically assess the current clinical evidence of efficacy and safety of GBE for EH. METHODS 7 electronic databases (Cochrane Library, PubMed, EMBASE, VIP, CBM, Wanfang data, and CNKI) were searched to identify randomized controlled trials (RCTs) of GBE for EH. Methodological quality was assessed independently using the Cochrane Handbook for Systematic Reviews of Interventions. RESULTS A total of 9 RCTs with 1012 hypertensive patients were identified and reviewed. Most RCTs were of high risk of bias with flawed study design and poor methodological quality. 6 trials demonstrated potential positive effect of GBE as complementary therapy on BP reduction when compared with antihypertensive drug therapy; however, it was not associated with a statistically significant effect on both SBP and DBP reduction in 3 other trials. Despite the positive findings, there were so many methodological limitations and significant clinical heterogeneity. Most of the trials did not report adverse effects, and the safety of GBE is still uncertain. CONCLUSION No confirmative conclusions on the efficacy and safety of GBE for EH could be drawn. More rigorous trials are warranted to support their clinical use.
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Zhang YQ, Guan L, Zhong ZY, Chang M, Zhang DK, Li H, Lai W. The anti-inflammatory effect of cherry blossom extract (Prunus yedoensis) used in soothing skincare product. Int J Cosmet Sci 2014; 36:527-30. [PMID: 25065693 DOI: 10.1111/ics.12149] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Accepted: 06/15/2014] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Previous investigations suggested that cherry blossoms could provide valuable bioactive materials. However, few observations regarding the anti-inflammatory effect of cherry blossoms were reported. This study was to explore the anti-inflammatory effect of cherry blossom extract (CBE), which was used as a soothing ingredient in skincare product. METHODS In vitro study, the anti-inflammatory effect of CBE on the nitric oxide (NO) inhibition assay in lipopolysaccharide (LPS)-treated RAW 264.7 cells was investigated. In vivo study, 40 volunteers were included in a randomized, single-blinded, placebo-controlled trial. 24-hour-occlusive test chambers were applied on the flexor side of the forearm with 3% sodium lauryl sulphate (SLS). Subsequently, the test areas were treated on 9 subsequent days with a cream containing 3% CBE or a placebo. Evaluation included a visual score and determination of erythema value (E value). RESULTS In vitro study, 2% CBE reduced NO production by 31.83% compared to the placebo. In the SLS irritant patch test, the visual score and erythema value of CBE were lower than that of the placebo on D5 and D9. CONCLUSION Cherry blossom extract shows good anti-inflammatory effect in vitro and in vivo and represents a promising functional ingredient in soothing skincare product by reducing skin inflammation.
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Ma RQ, He F, Wen HS, Li JF, Mu WJ, Liu M, Zhang YQ, Hu J, Qun L. Polymorphysims of CYP17-I Gene in the Exons Were Associated with the Reproductive Endocrine of Japanese Flounder (Paralichthys olivaceus). ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 25:794-9. [PMID: 25049628 PMCID: PMC4093092 DOI: 10.5713/ajas.2011.11489] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 02/03/2012] [Accepted: 01/17/2012] [Indexed: 11/27/2022]
Abstract
The cytochrome P450c17-I (CYP17-I) is one of the enzymes critical to gonadal development and the synthesis of androgens. Two single nucleotide polymorphisms (SNPs) were detected within the coding region of the CYP17-I gene in a population of 75 male Japanese flounder (Paralichthys olivaceus). They were SNP1 (c.C445T) located in exon2 and SNP2 (c.T980C (p.Phe307Leu)) located in exon5. Four physiological indices, which were serum testosterone (T), serum 17β-estradiol (E2), Hepatosomatic index (HSI), and Gonadosomatic index (GSI), were studied to examine the effect of the two SNPs on the reproductive endocrines of Japanese flounder. Multiple comparisons revealed that CT genotype of SNP1 had a much lower T level than CC genotype (p<0.05) and the GSI of individuals with CC genotype of SNP2 was higher than those with TT genotype (p<0.05). Four diplotypes were constructed based on the two SNPs and the diplotype D3 had a significantly lower T level and GSI. In conclusion, the two SNPs were significantly associated with reproductive traits of Japanese flounder.
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Xiong XJ, Li SJ, Zhang YQ. Massage therapy for essential hypertension: a systematic review. J Hum Hypertens 2014; 29:143-51. [PMID: 24990417 DOI: 10.1038/jhh.2014.52] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Revised: 05/14/2014] [Accepted: 05/22/2014] [Indexed: 01/12/2023]
Abstract
Massage, an ancient Chinese healing art, is widely practiced for symptom relief in hypertensive patients with anxiety, depression, headache, vertigo, chronic pain in neck, shoulder and back. A large number of case series and clinical trials have been published. However, it is still unclear whether massage can be recommended as an effective therapy for essential hypertension (EH). We estimated the current clinical evidence of massage for EH. Articles published before 10 December 2013 were searched using Cochrane Library, PubMed, EMBASE, Chinese Scientific Journal Database (VIP), Chinese Biomedical Literature Database, Wanfang data and Chinese National Knowledge Infrastructure. Randomized controlled trials comparing massage with any type of control intervention were included. Trials testing massage combined with antihypertensive drugs versus antihypertensive drugs were included as well. Meta-analysis was performed on the effects on blood pressure (BP). Twenty-four articles involving 1962 patients with EH were selected. Methodological quality of most trials was evaluated as generally low. Meta-analyses demonstrated that massage combined with antihypertensive drugs may be more effective than antihypertensive drugs alone in lowering both systolic BP (SBP; mean difference (MD): -6.92 (-10.05, -3.80); P<0.0001) and diastolic BP (MD: -3.63 (-6.18, -1.09); P=0.005); massage appears beneficial for reducing SBP (MD: -3.47 (-5.39, -1.56); P=0.0004) for hypertensive patients as compared with antihypertensive drugs. Safety of massage is still unclear. There is some encouraging evidence of massage for EH. However, because of poor methodological quality, the evidence remains weak. Rigorously designed trials are needed to validate the use of massage in future.
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Zhou PH, Li QL, Yao LQ, Xu MD, Chen WF, Cai MY, Hu JW, Li L, Zhang YQ, Zhong YS, Ma LL, Qin WZ, Cui Z. Peroral endoscopic remyotomy for failed Heller myotomy: a prospective single-center study. Endoscopy 2013; 45:161-6. [PMID: 23389963 DOI: 10.1055/s-0032-1326203] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND STUDY AIMS Recurrence/persistence of symptoms occurs in approximately 20 % of patients after Heller myotomy for achalasia. Controversy exists regarding the therapy for patients in whom Heller myotomy has failed. The aim of the current study was to evaluate the efficacy and feasibility of peroral endoscopic myotomy (POEM), a new endoscopic myotomy technique, for patients with failed Heller myotomy. PATIENTS AND METHODS A total of 12 patients with recurrence/persistence of symptoms after Heller myotomy, as diagnosed by established methods and an Eckardt score of ≥ 4, were prospectively included. The primary outcome was symptom relief during follow-up, defined as an Eckardt score of ≤ 3. Secondary outcomes were procedure-related adverse events, lower esophageal sphincter (LES) pressure on manometry, reflux symptoms, and medication use before and after POEM. RESULTS All 12 patients underwent successful POEM after a mean of 11.9 years (range 2 - 38 years) from the time of the primary Heller myotomy. No serious complications related to POEM were encountered. During a mean follow-up period of 10.4 months (range 5 - 14 months), treatment success was achieved in 11/12 patients (91.7 %; mean score pre- vs. post-treatment 9.2 vs. 1.3; P < 0.001). Mean LES pressure was 29.4 mmHg pre-treatment and 13.5 mmHg post-treatment (P < 0.001). One patient developed mild reflux symptoms and required intermittent medication with proton pump inhibitors. CONCLUSIONS POEM seems to be a promising new treatment for failed Heller myotomy resulting in short-term symptom relief in > 90 % of cases. Previous Heller myotomy may make subsequent endoscopic remyotomy more challenging, but does not prevent successful POEM.
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Zhang YQ, Cao XA. Evaluation of all-inorganic CdSe quantum dot thin films for optoelectronic applications. NANOTECHNOLOGY 2012; 23:275702. [PMID: 22705470 DOI: 10.1088/0957-4484/23/27/275702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Exchanging the original organic ligands of colloidal CdSe quantum dots (QDs) with inorganic metal chalcogenide SnS(4) ligands resulted in absorption peak redshifts and complete photoluminescence (PL) quenching in QD solids. The SnS(4)-capped QDs, meanwhile, were able to retain strong excitonic absorption. After the ligand exchange, the ITO/QDs/Al structure showed much higher electrical conductivity and reduced space-charge limited current. Its photocurrent spectral response increased by over two orders of magnitude and closely resembled the absorption spectrum of the QDs. However, it was found that mild thermal treatment above 200 °C transformed the SnS(4)-capped QD film into to a more conductive assembly, degrading its absorption and photocurrent generation. These results suggest that the inorganic ligands considerably enhanced the inter-dot electronic coupling in QD solids, leading to facile charge separation and transport. Our study thus demonstrates the potential applicability of colloidal QDs with metal chalcogenide ligands processed at low temperatures for efficient photodetection and solar energy conversion.
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Qiu ZY, Li G, Zhang YQ, Liu J, Hu W, Ma J, Zhang SM. Fine structure analysis and sintering properties of Si-doped hydroxyapatite. Biomed Mater 2012; 7:045009. [PMID: 22652464 DOI: 10.1088/1748-6041/7/4/045009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Si-doped hydroxyapatite (Si-HA) has been intensively investigated as a promising bone biomaterial because of the biomineralization and bone formation benefit from silicon addition. In the current work, Si-HA samples were synthesized by the aqueous precipitation method. The sintering property of Si-HA was studied in terms of phase composition and transition, which was influenced by the Si doping percentage and sintering temperature. The results indicate that all the as-prepared and sintered low Si doping samples (Si% ≤ 1.6 wt%) possess HA phases; while the high Si doping samples (Si% ≥ 2 wt%) present amorphous phases as prepared, and largely or even completely transform to β-tricalcium phosphate (β-TCP) phase after sintering at 1250 °C. The Rietveld refinement on x-ray diffraction patterns was conducted to determine the particle sizes, microstrain factors and anisotropic distributions. According to the refined results, the calculated anisotropic particle sizes correspond to the observations made by transmission electron microscopy. The microstrains also present anisotropic distributions in all refinements. The accurate variation in the fine structure of Si-HA has been studied by the improved refinements after considering the anisotropic distribution.
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Zhang YQ, Wu QP, Zhang JM, Yang XH. Effects of ozone on membrane permeability and ultrastructure in Pseudomonas aeruginosa. J Appl Microbiol 2011; 111:1006-15. [PMID: 21790913 DOI: 10.1111/j.1365-2672.2011.05113.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To examine the mechanism of ozone-induced damage to cytoplasmic membrane and cell ultrastructure of Pseudomonas aeruginosa ATCC27853. METHODS AND RESULTS Cell suspensions of Ps. aeruginosa ATCC27853 were treated with ozonated water. The leakages of cellular potassium (K⁺), magnesium (Mg²⁺) and adenosine triphosphate (ATP), determined by inductively coupled plasma/mass spectrometry (ICP/MS) and a commercial bioluminescence assay kit, were to assess ozone-induced damage to the cytoplasmic membrane. Maximum leakages of K⁺ and Mg²⁺ were attained, respectively, at 0·53 mg l⁻¹ ozone after 0·5 and 2 min with > 99% inactivation of culturable bacteria, while that of ATP was achieved at 0·67 mg l⁻¹ ozone after 1 min. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed that treated cells retained intact shapes and cytoplasm agglutinations and vacuoles occurred. CONCLUSIONS Ozone inactivates Ps. aeruginosa ATCC27853 by the combined results of increased cytoplasmic membrane permeability and cytoplasm coagulation, rather than by severe membrane disruption and cell lysis. SIGNIFICANCE AND IMPACT OF THE STUDY Pseudomonas aeruginosa is a common water-related pathogen. These insights into the leakage of cytoplasmic components and ultrastructural changes provide evidence for the mechanisms of ozone-mediated inactivation.
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Lee AS, Ghoreishi M, Cheng WK, Chang TYE, Zhang YQ, Dutz JP. Toll-like receptor 7 stimulation promotes autoimmune diabetes in the NOD mouse. Diabetologia 2011; 54:1407-16. [PMID: 21340621 DOI: 10.1007/s00125-011-2083-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 01/10/2011] [Indexed: 12/28/2022]
Abstract
AIMS/HYPOTHESIS The role of Toll-like receptor 7 (TLR7), a sensor of viral and self RNA, in promoting autoimmune diabetes remains unclear. Our goal was to determine the effect of TLR7 stimulation on the priming and activation of diabetogenic CD8(+) T cells. METHODS We explored the effects of CL097 (TLR7/8 agonist) and immunoregulatory sequence 661 (IRS661, TLR7 inhibitor) on bone marrow-derived dendritic cells (BMDCs), diabetogenic CD8(+) T cell function and autoimmune diabetes onset in NOD and 8.3 NOD T cell receptor transgenic mice (8.3 NOD mice). RESULTS TLR7 stimulation of NOD BMDCs increased activation and production of proinflammatory cytokines. In vivo administration of CL097 activated T cells and dendritic cells and increased levels of proinflammatory cytokines and type 1/2 IFNs in NOD mice. In vivo antigen-specific cytotoxicity studies revealed enhanced cytotoxicity against islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP, an islet autoantigen) peptide pulsed targets in NOD mice treated with CL097 plus CD40 agonist. This combination treatment accelerated the onset of autoimmune diabetes in 8.3 NOD mice. Likewise, topical treatment of NOD mice with a TLR7 agonist accelerated diabetes onset. Spontaneous disease in 8.3 NOD mice and accelerated disease in CL097+CD40 agonist-treated 8.3 NOD mice were delayed by IRS661 treatment, which is associated with inhibition of the endogenous upregulation of IFN-α levels within the pancreatic lymph nodes. CONCLUSIONS/INTERPRETATION TLR7 stimulation accelerates the spontaneous onset of autoimmune diabetes in 8.3 NOD and NOD mice. Conversely, TLR7 inhibition prevents the early events associated with diabetogenesis.
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Qu D, Song Y, Li WM, Pei XW, Wang ZX, Jia SR, Zhang YQ. Isolation and characterization of the organ-specific and light-inducible promoter of the gene encoding rubisco activase in potato (Solanum tuberosum). GENETICS AND MOLECULAR RESEARCH 2011; 10:621-31. [PMID: 21491372 DOI: 10.4238/vol10-2gmr1088] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Constitutive promoters have been widely used in crop biotechnology applications. Tissue-specific or inducible promoters, however, have advantages in some cases. We isolated the 731-bp 5' flanking sequence of a potato (Solanum tuberosum) gene, encoding ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) activase (RCA), which was isolated by genome walking. By using GUS as a reporter and with Northern blot analysis, the 702-bp fragment (referred to as StRCAp), ranging from nt -731 to -30 relative to the initiation code of the RCA gene, was analyzed in transgenic tobacco plants. The activity of StRCAp in leaves was 0.4-fold less than that of cauliflower mosaic virus 35S promoter, and was expressed throughout the green part of the light-grown transgenic T(1) seedlings, including cytoledons, leaves and young stems, but not roots. Further deletion analysis revealed that a shorter fragment (nt -249 to -30, StRCAp2) retained light-inducible features in cytoledons and leaves, but showed no detectable activity in young stems and roots. Although the activity of StRCAp2 in leaves was reduced significantly compared with that of StRCAp, the overall data indicated that cis-elements sufficient to regulate organ-specific and light-inducible transcription are within the 220-bp fragment. There is potential for application of StRCAp in plant genetic engineering.
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Zhang YQ, He DC, Meng QX. Effect of a mixture of steam-flaked corn and soybeans on health, growth, and selected blood metabolism of Holstein calves. J Dairy Sci 2010; 93:2271-9. [PMID: 20412943 DOI: 10.3168/jds.2009-2522] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Accepted: 01/07/2010] [Indexed: 12/16/2023]
Abstract
The objective of the experiment was to evaluate the effects of steam-flaked corn grains and soybeans on calf health, growth, and selected blood parameters. Holstein bull calves (n=30, approximately 7+/-3 d of age) were purchased from local dairy farms and offered milk, starter diets, and hay, and were then assigned to the experiment at 21+/-3 d of age. Calves were blocked into 3 treatments by birth date and body weight and randomly assigned to receive fresh milk and a commercial pelleted starter containing extruded corn and soybeans (ECS), steam-flaked corn and soybeans (SFCS), or ground corn and soybeans (GCS). The experiment was conducted with calves from 3 to 13 wk of age. Body weight, calf starter intake, milk intake, total dry matter intake, and body structural growth were not significantly influenced by corn and soybean processing during the study; however, feed efficiency was significantly improved by the SFCS treatment. Average daily gain generally decreased during the weaning week for all treatments, but did not differ significantly among treatments. Health incidences for calves fed the SFCS starter were lower than those fed the other 2 treatments. The blood hematocrit was higher for calves fed the SFCS starter than for those fed the GCS and ECS starters during wk 6 to 11. The concentration of plasma beta-hydroxybutyrate was higher for the calves fed the GCS and SFCS treatments than for those fed the ECS treatment during wk 6 to 13, but lower during wk 4 and 5. Plasma glucose concentrations decreased remarkably with increasing calf age but were not affected by corn and soybean processing. Plasma nonesterified fatty acids were influenced by calf age, and higher NEFA concentration was observed in the SFCS treatment than in the other 2 treatments during wk 5 to 9. Calves consuming the SFCS starter had similar average daily gain, milk intake, starter intake, total dry matter intake, and body structure, but had improved feed efficiency when compared with animals consuming the GCS and ECS starters. The SFCS starter decreased incidence of diarrhea during the postweaning period and required less veterinary treatment. These data suggest that the steam-flaking of corn and soybeans can influence the growth performance and the selected blood parameters of calves and that, in this study, the extrusion of corn and soybeans had no beneficial effect on the growth performance of calves.
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Niu J, Zhang YQ, Torner J, Nevitt M, Lewis CE, Aliabadi P, Sack B, Clancy M, Sharma L, Felson DT. Is obesity a risk factor for progressive radiographic knee osteoarthritis? ACTA ACUST UNITED AC 2009; 61:329-35. [PMID: 19248122 DOI: 10.1002/art.24337] [Citation(s) in RCA: 183] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To examine whether obesity increases the risk of progression of knee osteoarthritis (OA). METHODS We used data from the Multicenter Osteoarthritis Study, a longitudinal study of persons with or at high risk of knee OA. OA was characterized at baseline and 30 months using posteroanterior fixed-flexion radiographs and Kellgren/Lawrence (K/L) grading, with alignment assessed on full-extremity films. In knees with OA at baseline (K/L grade 2 or 3), progression was defined as tibiofemoral joint space narrowing on the 30-month radiograph. In knees without OA at baseline (K/L grade 0 or 1), incident OA was defined as the development of radiographic OA at 30 months. Body mass index (BMI) at baseline was classified as normal (<25 kg/m(2)), overweight (25-<30 kg/m(2)), obese (30-<35 kg/m(2)), and very obese (>or=35 kg/m(2)). The risk of progression was tested in all knees and in subgroups categorized according to alignment. Analyses were adjusted for age, sex, knee injury, and bone density. RESULTS Among the 2,623 subjects (5,159 knees), 60% were women, and the mean +/- SD age was 62.4 +/- 8.0 years. More than 80% of subjects were overweight or obese. At baseline, 36.4% of knees had tibiofemoral OA, and of those, only one-third were neutrally aligned. Compared with subjects with a normal BMI, those who were obese or very obese were at an increased risk of incident OA (relative risk 2.4 and 3.2, respectively [P for trend < 0.001]); this risk extended to knees from all alignment groups. Among knees with OA at baseline, there was no overall association between a high BMI and the risk of OA progression; however, an increased risk of progression was observed among knees with neutral but not varus alignment. The effect of obesity was intermediate in those with valgus alignment. CONCLUSION Although obesity was a risk factor for incident knee OA, we observed no overall relationship between obesity and the progression of knee OA. Obesity was not associated with OA progression in knees with varus alignment; however, it did increase the risk of progression in knees with neutral or valgus alignment. Therefore, weight loss may not be effective in preventing progression of structural damage in OA knees with varus alignment.
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Englund M, Niu J, Guermazi A, Roemer FW, Hunter DJ, Lynch JA, Lewis CE, Torner J, Nevitt MC, Zhang YQ, Felson DT. Effect of meniscal damage on the development of frequent knee pain, aching, or stiffness. ACTA ACUST UNITED AC 2007; 56:4048-54. [PMID: 18050201 DOI: 10.1002/art.23071] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
Background. RNA interference, a conserved mechanism in which a sequence‐specific gene‐silencing process is mediated by small interfering RNA (siRNA), is a promising method of gene therapy in treating a variety of viral diseases. Aim. To investigate the antiviral effects of siRNA on herpes simplex virus type 1 (HSV‐1) replication in Vero cells. Methods. The antiviral effects of siRNA duplexes targeting the VP16 and DNA polymerase genes of HSV‐1 were evaluated by yield‐reduction and plaque‐reduction assays. The effect of siRNA on the expression of target genes was measured by real‐time quantitative reverse transcription PCR. Results. Two siRNA duplexes (siRNA‐1, targeting VP16, and siRNA‐4, targeting DNA polymerase), were found to be highly effective in inhibiting HSV‐1 replication. siRNA‐1 and siRNA‐4 reduced HSV‐1 replication by around 2 log10 and 1 log10 in the yield‐‐reduction assay and by ∼85% and ∼70% in the plaque‐reduction assay, respectively. Significant decreases in the mRNA level of VP16 and DNA polymerase genes were detected after viral infection in the Vero cells pretreated with siRNA‐1 and siRNA‐4, respectively. Conclusion. These results indicate that siRNA can potently inhibit HSV‐1 replication in vitro, suggesting that siRNA‐based antiviral therapy may be a potential effective therapeutic alternative for patients with HSV‐1 infection.
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Hunter DJ, Zhang YQ, Niu JB, Felson DT, Kwoh K, Newman A, Kritchevsky S, Harris T, Carbone L, Nevitt M. Patella malalignment, pain and patellofemoral progression: the Health ABC Study. Osteoarthritis Cartilage 2007; 15:1120-7. [PMID: 17502158 PMCID: PMC2042530 DOI: 10.1016/j.joca.2007.03.020] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Accepted: 03/29/2007] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Patellofemoral (PF) joint osteoarthritis (OA) is strongly correlated with lower extremity disability and knee pain. Risk factors for pain and structural progression in PF OA are poorly understood. Our objective was to determine the association between patella malalignment and its relation to pain severity, and PF OA disease progression. METHODS We conducted an analysis of data from the Health ABC knee OA study. Health ABC is a community based, multi-center cohort study of 3075 Caucasian and Black men and women aged 70-79 at enrollment. Weight bearing skyline knee X-rays were obtained in a subset (595) of subjects, with and without knee pain, at year 2 and year 5 (mean follow-up 36 months). Films were read paired, and PF osteophytes (OST) and joint space narrowing (JSN) were scored on a 0-3 scale using the Osteoarthritis Research Society International atlas. We defined progression of PF OA as any increase in JSN score. Three measures of patella malalignment were made: sulcus angle; patella tilt angle; and patella subluxation medially or laterally (bisect offset). Knee symptoms were assessed using a knee specific Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) knee pain subscale. We assessed the relationship between baseline patella malalignment and pain severity (linear regression for WOMAC) and compartment specific PF OA progression (logistic regression for dichotomous outcomes). We classified continuous measures of patella alignment into quartile groups. We performed multivariable adjusted logistic regression models, including age, gender and body mass index (BMI) to assess the relation of baseline patella alignment to the occurrence of PF JSN progression using generalized estimating equations (GEE). RESULTS The subjects had a mean age 73.6 (SD 2.9), BMI 28.8 (SD 4.9), 40.3% male, and 46% were Black. Medial displacement of the patella predisposed to medial JSN progression; odds for each quartile 1, 1.2, 1.2, 2.2 (P for trend=0.03), whilst protecting from lateral JSN progression; odds for each quartile 1, 0.7, 0.6, 0.4 (P for trend=0.0004). Increasing patella tilt protected from medial JSN progression; odds for each quartile 1, 0.8, 0.5, 0.2 (P<0.0001) and trended to increasing pain severity (P=0.09). CONCLUSION Patella malalignment is associated with PF disease progression. Medial displacement and tilt of the patella predisposes to medial JSN progression, whilst lateral displacement is predictive of lateral JSN progression. The influence of patella malalignment has important implications since it is potentially modifiable through footwear, taping and/or knee bracing.
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Sun S, Cao H, Han M, Li TT, Zhao ZQ, Zhang YQ. Evidence for suppression of electroacupuncture on spinal glial activation and behavioral hypersensitivity in a rat model of monoarthritis. Brain Res Bull 2007; 75:83-93. [PMID: 18158100 DOI: 10.1016/j.brainresbull.2007.07.027] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 07/18/2007] [Accepted: 07/26/2007] [Indexed: 12/18/2022]
Abstract
Our previous study demonstrated that single intrathecal (i.t.) application of fluorocitrate, a glial metabolic inhibitor, synergized electroacupuncture (EA) antagonizing behavioral hypersensitivity in complete Freund's adjuvant (CFA)-induced monoarthritic rat. To further investigate the relationship between spinal glial activation and EA analgesia, the present study examined the effects of multiple EA on spinal glial activation evoked by monoarthritis (MA). The results showed that (1) unilateral intra-articular injection of CFA produced a robust glial activation on the spinal cord, which was associated with the development and maintenance of behavioral hypersensitivity; (2) multiple EA stimulation of ipsilateral "Huantiao" (GB30) and "Yanglingquan" (GB34) acupoints or i.t. injection of fluorocitrate (1 nmol) significantly suppressed spinal glial activation; (3) inhibitory effects of EA on spinal glial activation and behavioral hypersensitivity were significantly enhanced when EA combined with fluorocitrate, indicating that disruption of glial function may potentiate EA analgesia in inflammatory pain states. These data suggested that analgesic effects of EA might be associated with its counter-regulation to spinal glial activation, and thereby provide a potential strategy for the treatment of arthritis.
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Abstract
The genesis and development of tumor are closely connected with immune system and neuroendocrine system. To investigate the changes of neuroendocrine and immune system in leukemia patients and their probable connection with leukemia, we studied five groups of patients including leukemia patients with normal temperature, leukemia patients with high temperature and infection (high-leukocyte count group and low leukocyte count group), general patients with fever and healthy Chinese adult blood donors as control group. We determined their blood cell counts by blood count meter, determined their arginine vasopressin (AVP) levels in blood plasma by radioimmunoassay and their cross-reacting protein (CRP), and lipopolysaccharide (LPS) levels by immunoturbidimetry. Then we studied the difference and association among these indexes. Our results revealed a significant increase of AVP, LPS, and CRP levels in the blood of leukemia patients with normal temperature vs. normal people; Individual leukemia patients had high AVP levels although they had normal LPS and CRP levels; In the group of leukemia patients with high temperature and low leukocyte counts, the CRP level is significantly higher than some of other groups, while there was no significant increase in its AVP level. We conclude that no matter the temperature is normal or not, there were always neuroendocrine disturbance, inflammation, and inapparent infection in leukemia patient; To the leukemia patients with low leukocyte counts, the relationship between inflammation and neuroendocrine is more complicated.
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169
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Liu HH, Zhang YQ, Zhou Q, Molz FJ. An interpretation of potential scale dependence of the effective matrix diffusion coefficient. JOURNAL OF CONTAMINANT HYDROLOGY 2007; 90:41-57. [PMID: 17067718 DOI: 10.1016/j.jconhyd.2006.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2005] [Revised: 09/05/2006] [Accepted: 09/11/2006] [Indexed: 05/12/2023]
Abstract
Matrix diffusion is an important process for solute transport in fractured rock, and the matrix diffusion coefficient is a key parameter for describing this process. Previous studies have indicated that the effective matrix diffusion coefficient values, obtained from a large number of field tracer tests, are enhanced in comparison with local values and may increase with test scale. In this study, we have performed numerical experiments to investigate potential mechanisms behind possible scale-dependent behavior. The focus of the experiments is on solute transport in flow paths having geometries consistent with percolation theories and characterized by multiple local flow loops formed mainly by small-scale fractures. The water velocity distribution through a flow path was determined using discrete fracture network flow simulations, and solute transport was calculated using a previously derived impulse-response function and a particle-tracking scheme. Values for effective (or up-scaled) transport parameters were obtained by matching breakthrough curves from numerical experiments with an analytical solution for solute transport along a single fracture. Results indicate that a combination of local flow loops and the associated matrix diffusion process, together with scaling properties in flow path geometry, seems to be an important mechanism causing the observed scale dependence of the effective matrix diffusion coefficient (at a range of scales).
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170
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Ji RR, Kawasaki Y, Zhuang ZY, Wen YR, Zhang YQ. Protein kinases as potential targets for the treatment of pathological pain. Handb Exp Pharmacol 2007:359-89. [PMID: 17087130 DOI: 10.1007/978-3-540-33823-9_13] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pathological pain or clinical pain refers to tissue injury-induced inflammatory pain and nerve injury-induced neuropathic pain and is often chronic. Pathological pain is an expression of neural plasticity that occurs both in the peripheral nervous system (e.g., primary sensory nociceptors), termed peripheral sensitization, and in the central nervous system (e.g., dorsal horn and brain neurons), termed central sensitization. Our insufficient understanding of mechanisms underlying the induction and maintenance of injury-induced neuronal plasticity hinders successful treatment for pathological pain. The human genome encodes 518 protein kinases, representing one of the largest protein families. There is growing interest in developing protein kinase inhibitors for the treatment of a number of diseases. Although protein kinases were not favored as targets for analgesics, studies in the last decade have demonstrated important roles of these kinases in regulating neuronal plasticity and pain sensitization. Multiple protein kinases have been implicated in peripheral and central sensitization following intense noxious stimuli and injuries. In particular, mitogen-activated protein kinases (MAPKs), consisting of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK), are downstream to many kinases and are activated in primary sensory and dorsal horn neurons by nociceptive activity, growth factors and inflammatory mediators, contributing to the induction and maintenance of pain sensitization via posttranslational, translational, and transcriptional regulation. MAPKs are also activated in spinal glial cells (microglia and astrocytes) after injuries, leading to the synthesis of inflammatory mediators/neuroactive substances that act on nociceptive neurons, enhancing and prolonging pain sensitization. Inhibition of multiple kinases has been shown to attenuate inflammatory and neuropathic pain in different animal models. Development of specific inhibitors for protein kinases to target neurons and glial cells will shed light on the development of new therapies for debilitating chronic pain.
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Hunter DJ, Zhang YQ, Tu X, Lavalley M, Niu JB, Amin S, Guermazi A, Genant H, Gale D, Felson DT. Change in joint space width: hyaline articular cartilage loss or alteration in meniscus? ACTA ACUST UNITED AC 2006; 54:2488-95. [PMID: 16868968 DOI: 10.1002/art.22016] [Citation(s) in RCA: 209] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To explore the relative contribution of hyaline cartilage morphologic features and the meniscus to the radiographic joint space. METHODS The Boston Osteoarthritis of the Knee Study is a natural history study of symptomatic knee osteoarthritis (OA). Baseline and 30-month followup assessments included knee magnetic resonance imaging (MRI) and fluoroscopically positioned weight-bearing knee radiographs. Cartilage and meniscal degeneration were scored on MRI in the medial and lateral tibiofemoral joints using a semiquantitative grading system. Meniscal position was measured to the nearest millimeter. The dependent variable was joint space narrowing (JSN) on the plain radiograph (possible range 0-3). The predictor variables were MRI cartilage score, meniscal degeneration, and meniscal position measures. We first conducted a cross-sectional analysis using multivariate regression to determine the relative contribution of meniscal factors and cartilage morphologic features to JSN, adjusting for body mass index (BMI), age, and sex. The same approach was used for change in JSN and change in predictor variables. RESULTS We evaluated 264 study participants with knee OA (mean age 66.7 years, 59% men, mean BMI 31.4 kg/m(2)). The results from the models demonstrated that meniscal position and meniscal degeneration each contributed to prediction of JSN, in addition to the contribution by cartilage morphologic features. For change in medial joint space, both change in meniscal position and change in articular cartilage score contributed substantially to narrowing of the joint space. CONCLUSION The meniscus (both its position and degeneration) accounts for a substantial proportion of the variance explained in JSN, and the change in meniscal position accounts for a substantial proportion of change in JSN.
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Pang JL, Wu BL, He WX, Zhang YQ, Zhao HP, Xie ZH. Effect of antisense oligonucleotide against mouse dentine matrix protein 1 on mineralization ability and calcium ions metabolism in odontoblast-like cell line MDPC-23. Int Endod J 2006; 39:527-37. [PMID: 16776757 DOI: 10.1111/j.1365-2591.2006.01104.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM To study the mineralization ability and the dynamic changes of intracellular and extracellular concentrations of calcium ions in the odontoblast-like cell line MDPC-23 affected by antisense oligonucleotide (AS-ODN) against mouse dentine matrix protein 1 (DMP1). METHODOLOGY The expression of DMP1 in MDPC-23 cells was detected by an immunohistochemical method and its blocking outcome by the Western blot method. The alkaline phosphatase (ALP) activity, size and number of mineralized nodules, and the intracellular free ([Ca2+]if), total ([Ca2+]it) and the extracellular ([Ca2+]e) calcium ion concentrations in MDPC-23 cells in the experimental group affected with AS-ODN were compared with those in the control group (paired-samples t-test). RESULTS Dentine matrix protein 1 was stably expressed in a stable way in MDPC-23 cells; the expression was only just detectable at 12 h and became negative after 24 h affected by AS-ODN. Compared with the control groups, ALP activity of MDPC-23 cells in the AS-ODN group was decreased (P < 0.05), and both the number and size of mineralized nodules were smaller than those in the control group. [Ca2+]if in the AS-ODN group increased and then decreased after 24 h. [Ca2+]it dropped substantially to the lowest point at 24 h (P < 0.01). [Ca2+]e increased before treatment for 24 h and then dropped, however, it was still higher than that of the control group. CONCLUSIONS Antisense oligonucleotide against DMP1 could decrease mineralization ability and affect the intracellular and extracellular concentrations of calcium ions in MDPC-23 cells. This would indicate that DMP1 regulates the metabolism and transportation of calcium ions in odontoblasts, and thus boosts dentine mineralization.
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Sengupta M, Zhang YQ, Niu JB, Guermazi A, Grigorian M, Gale D, Felson DT, Hunter DJ. High signal in knee osteophytes is not associated with knee pain. Osteoarthritis Cartilage 2006; 14:413-7. [PMID: 16442316 DOI: 10.1016/j.joca.2005.11.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Accepted: 11/28/2005] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Our understanding of the local source of pain in osteoarthritis (OA) remains unclear. We undertook this study to determine if the presence of high-signal osteophytes on magnetic resonance imaging (MRI) was associated with pain presence, location or severity. METHODS Subjects were chosen from the Boston Osteoarthritis of the Knee Study, a natural history study of symptomatic knee OA. Assessments included knee MRI, pain assessments and information on weight and height. Osteophyte signal was defined as areas of increased signal intensity in the osteophyte on fat-suppressed T2 weighted images, and graded in the joint margins where osteophyte size is graded. All patients were evaluated with the frequent knee symptoms question for pain presence, the Western Ontario McMasters Osteoarthritis Index (WOMAC) for pain severity, and location of self-reported pain was recorded as present or absent based on locations identified on a standardized diagram. The osteophyte signal measures anywhere within one given knee were summed, creating an osteophyte signal aggregate. Logistic regression was conducted with quartile of osteophyte signal aggregate as the independent predictor and frequent knee symptom question as the dependent outcome. Association between quartile of osteophyte signal aggregate and pain severity on WOMAC was assessed using a linear regression. Logistic regression was used to evaluate the association between compartment-specific high-signal osteophytes aggregates (independent variable) and compartment-specific knee pain (dependent variable). Analyses were adjusted for gender, body mass index (BMI), and age. RESULTS Two hundred and seventeen subjects were included in this analysis. They were predominantly male and 75% of subjects had radiographic tibio-femoral (TF) OA, and the remainder had patello-femoral (PF) radiographic OA. We did not find any association of high-signal osteophytes with presence of pain, pain severity or self-reported pain location. CONCLUSION High-signal osteophytes detected on MRI are not associated with the presence of pain, pain severity or the self-reported location of pain.
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Hunter DJ, Zhang YQ, Niu JB, Tu X, Amin S, Clancy M, Guermazi A, Grigorian M, Gale D, Felson DT. The association of meniscal pathologic changes with cartilage loss in symptomatic knee osteoarthritis. ACTA ACUST UNITED AC 2006; 54:795-801. [PMID: 16508930 DOI: 10.1002/art.21724] [Citation(s) in RCA: 363] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To explore the role of meniscal tears and meniscal malposition as risk factors for subsequent cartilage loss in subjects with symptomatic osteoarthritis (OA). METHODS Study subjects were patients with symptomatic knee OA from the Boston Osteoarthritis of the Knee Study. Baseline assessments included knee magnetic resonance imaging (MRI) with followup MRI at 15 and 30 months. Cartilage and meniscal damage were scored on MRI in the medial and lateral tibiofemoral joints using the semiquantitative whole-organ magnetic resonance imaging score. Tibiofemoral cartilage was scored on MR images of all 5 plates of each tibiofemoral joint, and the meniscal position was measured using eFilm Workstation software. A proportional odds logistic regression model with generalized estimating equations was used to assess the effect of each predictor (meniscal position factor and meniscal damage as dichotomous predictors in each model) on cartilage loss in each of the 5 plates within a compartment. Models were adjusted for age, body mass index (BMI), tibial width, and sex. RESULTS We assessed 257 subjects whose mean +/- SD age was 66.6 +/- 9.2 years and BMI was 31.5 +/- 5.7 kg/m2; 42% of subjects were female, and 77% of knees had a Kellgren/Lawrence radiographic severity grade > or = 2. In the medial tibiofemoral joint, each measure of meniscal malposition was associated with an increased risk of cartilage loss. There was also a strong association between meniscal damage and cartilage loss. Since meniscal coverage and meniscal height diminished with subluxation, less coverage and reduced height also increased the risk of cartilage loss. CONCLUSION This study highlights the importance of an intact and functioning meniscus in patients with symptomatic knee OA, since the findings demonstrate that loss of this function has important consequences for cartilage loss.
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Zhang YQ, Limbird LE. Hetero-oligomers of alpha2A-adrenergic and mu-opioid receptors do not lead to transactivation of G-proteins or altered endocytosis profiles. Biochem Soc Trans 2005; 32:856-60. [PMID: 15494033 DOI: 10.1042/bst0320856] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Complexes of alpha(2A)-ARs (alpha(2A)-adrenergic receptors) and MORs (mu-opioid receptors), probably hetero-oligomers, were detected by co-immunoisolation after extraction from HEK-293 cells (human embryonic kidney 293 cells). Functional communication between these receptors is revealed by alpha(2A)-AR activation of a pertussis toxin-insensitive G(i)alpha subunit (termed as G(i)1) when fused with the MOR and evaluated in membranes from pertussis toxin-treated cells. However, the alpha(2A)-AR does not require transactivation through MOR, since quantitatively indistinguishable results were observed in cells co-expressing alpha(2A)-AR and a fusion protein of G(i)1 with the first transmembrane span of MOR (myc-MOR-TM1). Functional cross-talk among these alpha(2A)-AR-MOR complexes does not occur for internalization profiles; incubation with adrenaline (epinephrine) leads to endocytosis of alpha(2A)-AR but not MOR, while incubation with DAMGO ([D-Ala,NMe-Phe,Gly-ol]enkephalin) leads to endocytosis of MOR but not alpha(2A)-AR in cells co-expressing both the receptors. Hence, alpha(2A)-AR and MOR hetero-oligomers, although they occur, do not have an obligatory functional influence on one another in the paradigms studied.
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