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1.
Anat Rec (Hoboken) ; 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32175693

RESUMO

The functional regulation of the orexin system in the central nervous system is closely related to the occurrence and development of psychotic disorders. Abnormal changes in the lateral region of the hypothalamus are associated with the comorbidity of depression and physical symptoms, and how the traditional Chinese formula Xiaoyaosan regulates these changes may reveal aspects of the pathogenesis of depression. This study aimed to establish a rat model of depression in order to examine changes in Orexin A/OxR1 expression in the lateral region of the hypothalamus and the effects of Xiaoyaosan. Sixty specific pathogen-free (SPF) male healthy Sprague-Dawley (SD) rats were used in the experiment and randomly divided into the control group, the model group, the Xiaoyaosan group and the fluoxetine group. The depression model was established by 21-day chronic immobilization stress (CIS). Food intake and body weight were recorded, and the sucrose preference test (SPT) and open field test (OFT) were used to evaluate the model. Then, the expression of Orexin A/OxR1 in the hypothalamus was measured by ELISA, Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) analysis. The expression of Orexin A and OxR1 in the lateral hypothalamic area was significantly down regulated in the model group, compared with the control group. Xiaoyaosan significantly reversed these changes with obvious curative effects. Abnormal changes in Orexin A/OxR1 in the lateral hypothalamic area of rats with depression caused by chronic stress are closely related to the pathogenesis of depression accompanied by physical symptoms. Xiaoyaosan can improve depression accompanied by physical symptoms by regulating Orexin A/OxR1.

3.
Curr Osteoporos Rep ; 18(1): 57-66, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31955352

RESUMO

PURPOSE OF REVIEW: To provide an overview on recent technical development for quantifying marrow composition using magnetic resonance imaging (MRI) and spectroscopy (MRS) techniques, as well as a summary on recent findings of interrelationship between marrow adipose tissue (MAT) and skeletal health in the context of osteoporosis. RECENT FINDINGS: There have been significant technical advances in reliable quantification of marrow composition using MR techniques. Cross-sectional studies have demonstrated a negative correlation between MAT and bone, with trabecular bone associating more strongly with MAT than cortical bone. However, longitudinal studies of MAT and bone are limited. MAT contents and composition have been associated with prevalent vertebral fracture. The evidence between MAT and clinical fracture is more limited, and, to date, no studies have reported on the relationship between MAT and incident fracture. Increasing evidence suggests a dynamic role of marrow fat in skeletal health. Reliable non-invasive quantification of marrow composition will facilitate developing novel treatment strategies for osteoporosis.

5.
Mater Sci Eng C Mater Biol Appl ; 108: 110196, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924020

RESUMO

With the rapid development of dye and textile industry, the pollution of dye wastewater has aroused widespread public concern due to the potential risk to human health. Therefore, it is of significance for the removal of dye pollutants from wastewater. In this work, a green and efficient bio-adsorbent, graphene oxide modified persimmon tannin (PT-GO), has been fabricated through glutaraldehyde crosslinking method for efficient adsorption of methylene blue (MB) from aqueous solutions. The prepared PT-GO bio-adsorbent was analyzed by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, x-ray photoelectron spectra (XPS) and Brunauer-Emmett-Teller (BET) analysis. The adsorption behavior of the PT-GO bio-adsorbent towards MB dye in a batch adsorption process was investigated. The maximum MB adsorption capacity achieved 256.58 mg g-1 with MB concentration of 35 mg L-1 at 323 K. The Freundlich equilibrium isotherm and the pseudo-second order model fit the adsorption behavior very well. Thermodynamics data revealed that the adsorption of MB onto PT-GO bio-adsorbent was feasible, spontaneous and endothermic. Redox reactions, electrostatic interactions and π-π interactions dominated the adsorption of MB onto PT-GO bio-adsorbent. In addition, the regeneration of the PT-GO was efficiently achieved and MB removal efficiency remained high (88.3%) after fifth cycles. All these results indicated that PT-GO bio-adsorbent could be a promising biomass adsorbent for the removal of organic dye contaminants with non-toxic, efficient and low cost.

6.
Eur J Med Chem ; 186: 111851, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761381

RESUMO

Forty-eight analogues of CP-31398, an antitumor agent modulated the mutant p53 gene were synthesized and their cytotoxicities against four cancer cell lines with different p-53 status including bladder cell T24 (w-p53), gastric cell MGC-803 (m-p53), prostate cell DU145 (m-p53), prostate cell PC-3 (null-p53), lung cell A549 (w-p53) and normal liver cell line HL-7702 (w-p53) were examined. (E)-2-(4-Nitrostyryl)-4-(3-dimethylaminopropyl)-aminoquinazoline (10ah) was identified as the most potent compound in anti-proliferation against MGC-803 cells, with IC50 lowed to 1.73 µM, far potency than that of CP-31398. Molecular mechanism study revealed that 10ah and CP-31398 differ greatly in mechanism to exert their antitumor properties. 10ah could intercalate into DNA and resulted in significant DNA double-strand break. 10ah-treatment in MGC-803 cells increased the expression of p53, phosphorylated p53 (p-p53), CDK4, p21 to cause cell cycle arrest at G2/M phase, significantly up-regulated the levels of pro-apoptosis proteins Bak, Bax, Bim while down-regulated the anti-apoptosis proteins Bcl-2, Bcl-xL and the levels of cyclin B1, fluctuated the intracellular reactive oxygen species (ROS), Ca2+ and mitochondrial membrane potential, activated Caspase-9 and Caspase-3 to induce apoptosis. 10ah also displayed potent anticancer efficiency against MGC-803 xenograft tumors models, with tumor growth inhibition (TGI) up to 61.8% at 20 mg/kg without obvious toxicity.


Assuntos
Antineoplásicos/farmacologia , Quinazolinas/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Clivagem do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Quinazolinas/síntese química , Quinazolinas/química , Relação Estrutura-Atividade , Proteína Supressora de Tumor p53/genética
7.
Psychiatry Res ; 284: 112691, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31791704

RESUMO

Emerging evidence indicates that disruption of the intestinal flora play an important role in the pathogenesis of depression. As one of the causes of such disturbances, the role of antibiotics in depression risk is gradually being revealed. Herein, we review recent findings showing that the use of both single and multiple antibiotic regimens may be related to depression by changing the gut microbiota and the brain-gut axis. Based on recent discoveries, we also suggest that several brain-gut interactive mechanisms (particularly those involving nerve and glial cells, neurotransmitters, brain neurotrophic factors, inflammatory factors, short-chain fatty acids, circulating metabolites, blood-brain barrier, and oxidative stress) may help understand the effects of antibiotics on intestinal flora and its relationship with depression.

8.
J Bone Miner Res ; 35(2): 326-332, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31618468

RESUMO

Bone marrow adiposity (BMA) is associated with aging and osteoporosis, but whether BMA can predict bone loss and fractures remains unknown. Using data from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study, we investigated the associations between 1 H-MRS-based measures of vertebral bone marrow adipose tissue (BMAT), annualized change in bone density/strength by quantitative computed tomography (QCT) and DXA, and secondarily, with incident clinical fractures and radiographic vertebral fractures among older adults. The associations between BMAT and annualized change in bone density/strength were evaluated using linear regression models, adjusted for age, body mass index (BMI), diabetes, estradiol, and testosterone. Cox proportional hazards models were used to evaluate the associations between baseline BMAT and incident clinical fractures, and logistic regression models for incident vertebral fractures. At baseline, mean ± SD age was 80.9 ± 4.2 and 82.6 ± 4.2 years in women (n = 148) and men (n = 150), respectively. Mean baseline BMAT was 55.4% ± 8.1% in women and 54.1% ± 8.2% in men. Incident clinical fractures occurred in 7.4% of women over 2.8 years and in 6.0% of men over 2.2 years. Incident vertebral fractures occurred in 12% of women over 3.3 years and in 17% of men over 2.7 years. Each 1 SD increase in baseline BMAT was associated with a 3.9 mg2 /cm4 /year greater loss of spine compressive strength index (p value = .003), a 0.9 mg/cm3 /year greater loss of spine trabecular BMD (p value = .02), and a 1.2 mg/cm3 /year greater loss of femoral neck trabecular BMD (p value = .02) in women. Among men, there were no associations between BMAT and changes in bone density/strength. There were no associations between BMAT and incident fractures in women or men. In conclusion, we found greater BMAT is associated with greater loss of trabecular bone at the spine and femoral neck, and greater loss of spine compressive strength, in older women. © 2019 American Society for Bone and Mineral Research.

9.
Infect Control Hosp Epidemiol ; 41(2): 187-193, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31818336

RESUMO

OBJECTIVE: To estimate the effects of continuous daily treatment with different acid suppressants on the risk of ventilator-associated events in critically ill patients. DESIGN: Retrospective cohort study. PATIENTS: Adult critically ill patients who underwent mechanical ventilation for ≥3 days during an inpatient admission between January 2006 and December 2014. METHODS: We estimated the 30-day cumulative risk ratios (RRs) for ventilator-associated events comparing daily proton pump inhibitor (PPI) versus daily histamine-2-receptor antagonist (H2RA) strategies while controlling for time-fixed and time-varying confounding and accounting for competing events. RESULTS: Of 6,133 patients, on ventilation day 3, 58.8% received H2RAs, 26.1% received PPIs, and 4.1% received sucralfate. Patients frequently changed treatment throughout follow-up. Among 4,595 patients receiving PPIs or H2RAs on day 3, we found no differences in risk estimates for ventilator mortality and extubation alive comparing daily PPI versus daily H2RA strategies: RR, mortality, 1.03 (95% CI, 0.89-1.22); extubation alive, 1.00 (95% CI, 0.96-1.03). We found similar results after accounting for PPI dose. For possible ventilator-associated pneumonia (PVAP) and infection-related ventilator-associated complication (IVAC), point estimates were larger, but the 95% CIs crossed 1.0: RR PVAP, 1.25 (95% CI, 0.80-1.94); IVAC, 0.89 (95% CI, 0.64-1.17). The magnitude of effect estimates depended on PPI dose. The RR for PVAP, high-dose PPI versus H2RA, was 1.53 (95% CI, 0.82-2.51), and for low-dose PPI versus H2RA, the RR was 0.97 (95% CI, 0.47-1.63). For IVAC, high-dose PPI versus H2RA, the RR was 1.01 (95% CI, 0.66-1.42), and for low-dose PPI versus H2RA, the RR was 0.78 (95% CI, 0.50-1.11). CONCLUSIONS: We estimated no effect of daily PPI versus daily H2RA on risk of mortality or extubation alive in critically ill patients. Further investigation with larger samples is warranted for PVAP and IVAC.

10.
Complement Med Res ; 27(1): 47-54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31394544

RESUMO

BACKGROUND: Xiaoyaosan (XYS) has achieved definite curative effects in clinic. However, the mechanism is not clear. Previous studies of our team indicated XYS improved anxiety-like behaviors through inhibiting c-Jun N-terminal kinase (JNK) signaling pathway of hippocampus. OBJECTIVES: In the study, we explored whether the JNK signaling pathway is involved in the mechanism of XYS treating depression. METHOD: Forty-eight rats were divided randomly into 4 groups (n = 12): the control group (deionized water, p.o.), the model group (deionized water, p.o.), the fluoxetine group (2.08 mg/kg/day, p.o.), and the XYS group (3.9 g/kg/day, p.o.). All rats except for the control group were given continuous 21 days of chronic immobilization stress (CIS; 3 h/day). On day 29, the body weights and the behavioral tests, including the novelty suppressed feeding test, the open field test, and the elevated plus maze test, were measured. On day 30, all the rats were sacrificed, and three indices of the JNK signaling pathway were tested by Western blot. RESULTS: The body weight and behavioral tests of all groups indicated that 21 days of CIS induced depression-like behaviors. After 21 days of treatment with fluoxetine and XYS, changes were seen in body weight, behaviors, and JNK, phosphorylated JNK (P-JNK), and phosphorylated c-Jun (P-c-Jun) levels in the hippocampus. CONCLUSIONS: XYS ameliorated the depression-like behaviors, potentially through affecting the JNK signaling pathway in the hippocampus.

11.
Acta Pharmacol Sin ; 41(2): 229-236, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31431733

RESUMO

In chronic infectious diseases caused by gram-negative bacteria, such as osteomyelitis, septic arthritis, and periodontitis, osteoclastic activity is enhanced with elevated inflammation, which disturbs the bone homeostasis and results in osteolysis. Lipopolysaccharide (LPS), as a bacteria product, plays an important role in this process. Recent evidence shows that an antimalarial drug artesunate attenuates LPS-induced osteolysis independent of RANKL. In this study we evaluated the effects of artesunate on LPS-induced osteoclastogenesis in vitro and femur osteolysis in vivo, and explored the mechanisms underlying the effects of artesunate on LPS-induced osteoclast differentiation independent of RANKL. In preosteoclastic RAW264.7 cells, we found that artesunate (1.56-12.5 µM) dose dependently inhibited LPS-induced osteoclast formation accompanied by suppressing LPS-stimulated osteoclast-related gene expression (Fra-2, TRAP, Cathepsin K, ß3-integrin, DC-STAMP, and Atp6v0d2). We showed that artesunate (3.125-12.5 µM) inhibited LPS-stimulated nuclear factor of activated T cells c1 (NFATc1) but not NF-κB transcriptional activity; artesunate (6.25, 12.5 µM) significantly inhibited LPS-stimulated NFATc1 protein expression. Furthermore, artesunate treatment markedly suppressed LPS-induced Ca2+ influx, and decreased the expression of PP2B-Aα (calcineurin) and pPLCγ1 in the cells. In addition, artesunate treatment significantly decreased the expression of upstream signals TLR4 and TRAF6 during LPS-induced osteoclastogenesis. Administration of artesunate (10 mg/kg, ip) for 8 days effectively inhibited serum TNF-α levels and ameliorated LPS (5 mg/kg, ip)-induced inflammatory bone loss in vivo. Taken together, artesunate attenuates LPS-induced inflammatory osteoclastogenesis by inhibiting the expression of TLR4/TRAF6 and the downstream PLCγ1-Ca2+-NFATc1 signaling pathway. Artesunate is a valuable choice to treat bone loss induced by gram-negative bacteria infection or inflammation in RANKL-independent pathway.

12.
Electrophoresis ; 41(3-4): 175-182, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31743461

RESUMO

We report the first application of hydrophobic interaction between graphene oxide (GO) and negatively charged enzymes to fabricate CE-integrated immobilized enzyme microreactors (IMERs) by a simple and reliable immobilization procedure based on layer by layer assembly. L-lactate dehydrogenase (L-LDH), which is negatively charged during the enzymatic reaction, is selected as the model enzyme. Various spectroscopic techniques, including SEM, FTIR, and UV-vis are used to characterize the fabricated CE-IMERs, demonstrating the successful immobilization of enzymes on the negatively charged GO layer in the capillary surface. The IMER exhibits excellent repeatability with RSDs of inter-day and batch-to-batch less than 3.49 and 6.37%, respectively, and the activity of immobilized enzymes remains about 90% after five-day usage. The measured Km values of pyruvate and NADH of the immobilized L-LDH are in good agreement with those obtained by free enzymes. The results demonstrate that the hydrophobic interactions and/or π-π stacking is significant between the GO backbone and the aromatic residues of L-LDH and favorable to fabrication of CE-integrated IMERs. Finally, the method is successfully applied to the determination of pyruvate in beer samples.

13.
Mol Imaging Biol ; 22(1): 105-114, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31065895

RESUMO

PURPOSE: Tumor necrosis factor alpha (TNFα) drives inflammation and bone degradation in patients with rheumatoid arthritis (RA). Some RA patients experience a rapid clinical response to TNFα inhibitors such as certolizumab pegol (CZP) while other patients show limited to no response. Current methods for imaging RA have limited sensitivity and do not assist in the selection of patients most likely to respond to immune-mediated therapy. Herein, we developed a novel positron emission tomography (PET) radiotracer for immuno-PET imaging of TNFα in transgenic human TNFα-expressing mice. PROCEDURES: CZP was modified with p-isothiocyanatobenzyl-deferoxamine (DFO) and radiolabeled with Zr-89. The biological activity of [89Zr]DFO-CZP was evaluated by HPLC and binding assay using human recombinant TNFα (hTNFα). The feasibility of specific immuno-PET imaging of human TNFα was assessed in a transgenic mouse model of RA that expresses human TNFα. This model resembles the progression of RA in humans by maintaining lower levels of circulating hTNFα and exhibits chronic arthritis in the forepaw and hind paw joints. The dosimetry of [89Zr]DFO-CZP in humans was estimated using microPET/CT imaging in Sprague Dawley rats. RESULTS: [89Zr]DFO-CZP was isolated with radiolabeling yields of 85 ± 6 % (n = 5) and specific activities ranging from 74 to 185 MBq/mg (n = 5). Following size exclusion purification, the radiochemical purity of [89Zr]DFO-CZP was greater than 97 %. [89Zr]DFO-CZP retained high immunoreactivity with more than 95 % of the radioactivity shifted into higher molecular weight complexes. Images showed increasing uptake of the tracer in forepaw and hind paw joints with disease progression. No uptake was observed in the model previously administered with an excess amount of unmodified CZP and in normal control mice, demonstrating in vivo specific uptake of [89Zr]DFO-CZP. CONCLUSION: The feasibility of immuno-PET imaging of human TNFα with [89Zr]DFO-CZP has been demonstrated in a preclinical model of RA.

14.
Biochem Pharmacol ; 172: 113762, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31843541

RESUMO

IKK-ß is indispensable for inflammatory osteolysis, the functional residues of IKK-ß are therapeutic drug targets for developing inhibitors to treat multiple diseases now. Thus it remains appealing to find the new residues of IKK-ß to influence osteoclasts for alleviating bone loss diseases such as rheumatoid arthritis (RA). By employing IKK-ß cysteine 46-A transgenic (IKK-ßC46A) mice, we found that mutation of cysteine 46 to alanine in IKK-ß exacerbated inflammatory bone destruction in vivo, and increased osteoclast differentiation and bone resorption ex vivo and in vitro. Consistent with these, IKK-ß kinase activity as well as c-Fos, NFATc1 were up-regulated in bone marrow macrophages (BMMs) from IKK-ßC46A mice during RANKL-induced osteoclastogenesis. Of interesting, we further identified and demonstrated that the expressions of mPGES-1 and caveolin-1 were heightened in BMMs of IKK-ßC46A mice compared to those in WT mice in RANKL-induced osteoclastogenesis. Together, it revealed that mutating cysteine 46 in IKK-ß could increase caveolin-1 and mPGES-1 expression to facilitate osteoclast differentiation and osteolysis. Cysteine 46 can serve as a novel target in IKK-ß for designing inhibitors to treat osteolysis.

15.
J Nanosci Nanotechnol ; 20(3): 1899-1906, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492359

RESUMO

Candida rugosa lipase was immobilized in this study using CaCl2/CMC nanoparticles that yielded a lipase loading capacity of 127 mg/g, with better thermal stability and activity of 91.8%. The hydrolysis of racemic 2-phenylpropionic acid isopropyl ester by free and immobilized Candida rugosa lipase was investigated in the mixed organic-solvent composed of isooctane and methyl tert-butyl ether (9.5:0.5, V/V). The optimal conditions were 35 °C and pH 7.5 for free Candida rugosa lipase hydrolysis. We obtained (S)-2-phenylpropionic acid with 44.85% conversion, 95.75% enantiomeric excess and enantiomeric ratio of 112. The CaCl2/CMC nanoparticles immobilized Candida rugosa lipase possesses high enantioselectivity, with E = 237 at 40 °C and pH 7.5. It was efficiently reusable in four cycles and appropriately enhanced enantioselectivity within 120-240.

16.
J Sci Food Agric ; 100(1): 184-192, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472017

RESUMO

BACKGROUND: Slight acidic electrolyzed water (SAEW) has been widely used in cleaning systems of fruit and vegetables. It strongly reduces microbial contamination. However, no information is available on whether SAEW offers the potential for fresh jujube cleaning. The purposes of this study were, first, to compare the effectiveness of SAEW with commercial sanitizers (i.e. sodium hypochlorite (NaClO) or calcium hypochlorite (Ca(ClO)2 )) on 'Jiancui' jujube; second, to determine the response of fruit decay, tissue calcium (Ca) content, and quality attributes to dip application of calcium nitrate (Ca(NO3 )2 ) by concentration; and third, to investigate the effects of SAEW combined with Ca(NO3 )2 or calcium acetate (Ca(OAc)2 )) on fruit Ca uptake, quality attributes, and bioactive compounds. RESULTS: Fruits washed with NaClO, Ca(ClO)2 , or an SAEW solution showed no difference in reduction of decay incidence. In contrast to NaClO treatment, SAEW or Ca(ClO)2 significantly retarded losses in fruit firmness (FF), green color (hue angle), and skin lightness (L*), and maintained intact pericarp tissue structure during storage at 1 °C. Application of Ca(NO3 )2 at 5-10 g L-1 effectively promoted Ca2+ uptake and minimized declines in FF and L* value but had no effect on decay development. Adding 10 g L-1 Ca(NO3 )2 or Ca(OAc)2 to SAEW provided an additional benefit in increasing decay resistance, increasing Ca2+ into fruit and increasing levels of bioactive compounds in jujube fruit. CONCLUSION: SAEW in combination with Ca(NO3 )2 or Ca(OAc)2 has commercial potential for fresh jujube disinfection and improving storage quality as a result of the cleaning processes. © 2019 Society of Chemical Industry.


Assuntos
Acetatos/farmacologia , Compostos de Cálcio/farmacologia , Cálcio/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/química , Nitratos/farmacologia , Ziziphus/efeitos dos fármacos , Eletrólise , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Controle de Qualidade , Água/química , Ziziphus/química
17.
J Orthop Res ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31788845

RESUMO

The current study looks to: (i) investigate postural stability following anterior cruciate ligament (ACL) reconstruction, as assessed by Y-Balance Test, by comparing single-leg balance of the injured limb against those of controls and the uninjured limb; (ii) analyze the relationship between postural stability symmetry with localized cartilage matrix changes and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Bilateral knee MRI of 36 patients who underwent ACL reconstruction were performed before surgery, 6 months, 1 year, and 2 years, postoperatively. Postural stability was evaluated based on Y-Balance Test at 1 and 2 years. ACL patients were also split into three groups based on postural stability symmetry at 2 years and symmetry thresholds associated with elevated risks of lower extremity injury. Voxel-based relaxometry employing analysis of covariance was used to analyze localized differences in cartilage composition at all time-points (using quantitative magnetic resonance [MR] T1ρ and T2 mapping) between the three groups. The ACL patients displayed no significant deficits in postural stability. Compared with symmetric patients, those with asymmetric postural stability at 2 years had significantly prolonged cartilage T1ρ-indicating deterioration of the cartilage matrix-specifically in the injured knee's medial tibia as early as 6-month post-reconstruction. Prolonged T1ρ in asymmetric patients persisted up to 2 years, where the group also reported worse KOOS. Our results demonstrate an association between early stages of cartilage matrix deterioration and postural stability symmetry that may manifest in elevated lower extremity injury risk and worse patient-reported outcomes. Quantitative MR, in combination with local analysis performed with voxel-based relaxometry, is a tool to further study this relationship. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

18.
Magn Reson Med ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31793071

RESUMO

PURPOSE: Fully automatic tissue segmentation is an essential step to translate quantitative MRI techniques to clinical setting. The goal of this study was to develop a novel approach based on the generative adversarial networks for fully automatic segmentation of knee cartilage and meniscus. THEORY AND METHODS: Defining proper loss function for semantic segmentation to enforce the learning of multiscale spatial constraints in an end-to-end training process is an open problem. In this work, we have used the conditional generative adversarial networks to improve segmentation performance of convolutional neural network, such as UNet alone by overcoming the problems caused by pixel-wise mapping based objective functions, and to capture cartilage features during the training of the network. Furthermore, the Dice coefficient and cross entropy losses were incorporated to the loss functions to improve the model performance. The model was trained and tested on 176, 3D DESS (double-echo steady-state) knee images from the Osteoarthritis Initiative data set. RESULTS: The proposed model provided excellent segmentation performance for cartilages with Dice coefficients ranging from 0.84 in patellar cartilage to 0.91 in lateral tibial cartilage, with an average Dice coefficient of 0.88. For meniscus segmentation, the model achieves 0.89 Dice coefficient for lateral meniscus and 0.87 Dice coefficient for medial meniscus. The results are superior to previously published automatic cartilage and meniscus segmentation methods based on deep learning models such as convolutional neural network. CONCLUSION: The proposed UNet-conditional generative adversarial networks based model demonstrated a fully automated segmentation method with high accuracy for knee cartilage and meniscus.

19.
Front Pharmacol ; 10: 1344, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824310

RESUMO

Osteoporosis is a bone disease characterized by increasing osseous fragility and fracture due to the reduced bone mass and microstructural degradation. Primary pharmacological strategies for the treatment of osteoporosis, hormone replacement treatment (HRT), and alendronate therapies may produce adverse side-effects and may not be recommended for long-term usage. Some classic and bone-specific natural Chinese medicine are very popularly used to treat osteoporosis and bone fracture effectively in clinical with their potential value in bone growth and development, but with few adverse side-effects. Current evidence suggests that the treatments appear to improve bone metabolism and attenuate the osteoporotic imbalance between bone formation and bone resorption at a cellular level by promoting osteoblast activity and inhibiting the effects of osteoclasts. The valuable therapies might, therefore, provide an effective and safer alternative to primary pharmacological strategies. Therefore, the purpose of this article is to comprehensively review these classic and bone-specific drugs in natural Chinese medicines for the treatment of osteoporosis that had been deeply and definitely studied and reported with both bone formation and antiresorption effects, including Gynochthodes officinalis (F.C.How) Razafim. & B.Bremer (syn. Morinda officinalis F.C.How), Curculigo orchioides Gaertn., Psoralea corylifolia (L.) Medik Eucommia ulmoides Oliv., Dipsacus inermis Wall. (syn. Dipsacus asperoides C.Y.Cheng & T.M.Ai), Cibotium barometz (L.) J. Sm., Velvet Antler, Cistanche deserticola Ma, Cuscuta chinensis Lam., Cnidium monnieri (L.) Cusson, Epimedium brevicornum Maxim, Pueraria montana (Lour.) Merr. and Salvia miltiorrhiza Bunge., thus providing evidence for the potential use of alternative Chinese medicine therapies to effectively treat osteoporosis.

20.
J Orthop Res ; 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31868948

RESUMO

T1 ρ and T2 magnetic resonance imaging (MRI) may allow for a noninvasive assessment of ligamentization after anterior cruciate ligament (ACL) reconstruction. We hypothesized that ACL graft T1 ρ and T2 relaxation times would decrease over time, that T1 ρ and T2 relaxation times would be inversely correlated with Knee Osteoarthritis Outcome Scores (KOOS), and that T1 ρ and T2 values would be lower for autograft relative to allograft reconstruction. Thirty-nine patients (age: 30.5 ± 8.2 years) were followed prospectively after ACL reconstruction with hamstring autograft (N = 27) or soft-tissue allograft (N = 12). Magnetic resonance (MR) imaging and KOOS surveys were completed at 6, 12, 24, and 36 months after surgery. ACL graft was segmented to define T1 ρ and T2 relaxation times. Relaxation times were compared between time points with ANOVA tests. Log-transformed autograft and allograft relaxation times were compared with the Student t tests. The relationship between KOOS and relaxation times at 24 months was investigated with Spearman's rank correlation. ACL graft T1 ρ relaxation times were significantly higher at 6 months relative to 12 months (P = .042), 24 months (P < .001), and 36 months (P < .001). ACL graft T2 relaxation times were significantly higher at 6 months relative to 12 months (P = .036), 24 months (P < .001), and 36 months (P < .001). T1 ρ and T2 relaxation times were significantly lower for autograft reconstruction vs allograft reconstruction at 24 months postreconstruction. Two-year KOOS Sports, Pain, and Symptoms were significantly inversely correlated with T1 ρ and T2 relaxation times. T1 ρ and T2 sequences may offer a noninvasive method for monitoring ACL graft maturation that correlates with patient-reported knee function after ACL reconstruction.

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