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1.
J Mech Behav Biomed Mater ; 151: 106356, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38181571

RESUMEN

In this paper, the effects of different composite plates on the healing of femoral fractures were studied by numerical simulation. The healing model of femoral fracture was established by ABAQUS display solver. Based on the fuzzy logic theory, the process of callus differentiation at femoral fracture was considered under the joint action of biological variables and mechanical stimulation, and the healing process of femur was simulated. Compare the stress on the screw, concentration of callus bone and cartilage, and callus healing performance of the carbon/epoxy composite (WSN3k) plate, glass/polypropylene composite (Twintex) plate, and stainless steel plate at various stages of bone healing, and investigate the impact of composite plates on the bone healing process. The results showed that the modulus of the plate had a notable impact on bone healing. Compared to stainless steel plate, the composite plate (due to its lower stiffness) exhibiting superior healing performance. Altering the sequence of composite laminates may modify the bone healing efficiency, and the wsn3k [0]18 composite plate exhibits superior healing performance.


Asunto(s)
Fracturas del Fémur , Acero Inoxidable , Humanos , Fracturas del Fémur/cirugía , Cicatrización de Heridas , Fémur/diagnóstico por imagen , Placas Óseas , Callo Óseo , Curación de Fractura , Fijación Interna de Fracturas/métodos , Fenómenos Biomecánicos
2.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1022831

RESUMEN

Objective:To evaluate the optical performance of two aspheric intraocular lenses (IOL) AcrySof IQ SN60WF and Proming A1-UV with identical negative spherical aberration values, using the optical bench OptiSpheric IOL R&D through an in vitro study. Methods:The optical performance of + 20.0 D blue-light filtering SN60WF and monofocal high-order aspheric non blue-light filtering A1-UV IOL was evaluated through cornea models with the spherical aberration of 0 μm (ISO-1) and + 0.28 μm (ISO-2) under apertures of 3.0 mm and 4.5 mm via the optical bench OptiSpheric IOL R&D.The modulation transfer function (MTF) and USAF 1951 resolution test chart were employed to measure the IOL with centering, decentration of 0.3, 0.5, 0.7, 0.9 and 1.1 mm, as well as tilt of 3°, 5°, 7°, 9° and 11°.The spectral transmittance of IOL was measured with the UV-3300 UV-VIS spectrophotometer.Results:Compared with the A1-UV IOL, the spectral transmittance of SN60WF for blue light with wavelengths of 400-500 nm was significantly reduced, which effectively reduced the passage of blue light.At an aperture of 3.0 mm, the MTF values at 100 lp/mm spatial frequency for the centered SN60WF and A1-UV were 0.576 and 0.598 under ISO-1 corneal measurement conditions, 0.564 and 0.563 under ISO-2 conditions.At an aperture of 4.5 mm, the MTF values were 0.238 and 0.404 under ISO-1 corneal measurement conditions, and 0.438 and 0.339 under ISO-2 conditions.The MTF values of A1-UV and SN60WF at 3.0 mm aperture and 100 lp/mm spatial frequency under ISO-1 corneal measurement conditions were larger than those under ISO-2 corneal measurement conditions.Under ISO-1 corneal measurement conditions with a 3.0 mm aperture, A1-UV had a better optical quality compared to SN60WF, whereas under ISO-2 corneal measurement conditions, the optical quality of both IOLs was similar.Under the 3.0 mm aperture, the MTF values of SN60WF and A1-UV at a decentration of 0.3 mm and 100 lp/mm spatial frequency were 0.414 and 0.571 under ISO-1 corneal measurement conditions, 0.438 and 0.512 under ISO-2 corneal measurement conditions, respectively.The MTF values of SN60WF and A1-UV at a tilt of 3° were 0.522 and 0.597 under ISO-1 corneal measurement conditions, and 0.532 and 0.531 under ISO-2 corneal measurement conditions.The MTF values and USAF resolution test chart of A1-UV had no significant change between the two corneal measurement conditions.When subjected to equal degrees of decentration or tilting, except for the ISO-1 corneal measurement conditions at a 4.5 mm aperture, the MTF values of A1-UV showed a gradual decline across various spatial frequencies compared to SN60WF.With the increase in aperture size, the impact of IOL decentration or tilting on MTF values and USAF 1951 resolution test chart became more notable for A1-UV relative to SN60WF.Conclusions:The SN60WF IOL effectively filters blue light within the wavelength range of 400-500 nm.However, when both IOL experience decentration greater than 0.3 mm or tilting beyond 3°, the optical quality of the IOL will decline.A1-UV has a distinct advantage over SN60WF in terms of resistance to both decentration and tilting-induced optical performance degradation in vitro.

3.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-931092

RESUMEN

Objective:To investigate the repeatability and correlation in tilt and decentration measurement of crystalline lens and intraocular lens (IOL) under non-mydriatic and mydriatic conditions using swept-source ocular coherence tomography CASIA2.Methods:A diagnostic test study was conducted.A total of 109 cataract patients (157 eyes) who received phacoemulsification with IOL implantation surgery in the Affiliated Hospital of North Sichuan Medical College from March to July 2020 were enrolled.The decentration and tilt of crystalline lens and IOL under non-mydriatic and mydriatic conditions were measured for three times by a single examiner using CASIA2 before and one week after surgery.The 0.5% compound tropicamide eye drops were used to dilate.Repeatability was evaluated by within-standard deviation, test-retest repeatability (TRT), coefficient of variation (CoV) and intraclass correlation coefficient (ICC). The correlation in decentration and tilt of crystalline lens and IOL between before and after mydriasis was assessed by Pearson correlation coefficient.This study adhered to the Declaration of Helsinki, and the study protocol was approved by an Ethics Committee of the Affiliated Hospital of North Sichuan Medical College (No.2020ER030-1). Written informed consent was obtained from all subjects before any medical examination.Results:The decentration of crystalline lens under non-mydriatic and mydriatic conditions was (0.217±0.112)mm and (0.220±0.110)mm, respectively, and the tilt was (5.017±1.422)° and (5.310±1.645)°, respectively.The decentration of IOL under non-mydriatic and mydriatic conditions was (0.245±0.136)mm and (0.250±0.145)mm, respectively, and the tilt was (5.144±1.345)° and (5.437±1.646)°, respectively.No significant difference was found between non-mydriatic and mydriatic conditions (all at P>0.05). Under both non-mydriatic and mydriatic conditions, the crystalline lenses of both eyes decentered and tilted toward the inferotemporal direction, and the IOL of right eyes decentered toward the inferior and tilted toward the inferotemporal direction, and the IOL of left eyes decentered and tilted toward the inferotemporal direction.Except the crystalline lens decentration, the measurement repeatability of crystalline lens tilt, IOL decentration and tilt in cataract patients before and after mydriasis was good, with ICC range in 0.815-0.984, TRT<50% and CoV≤14.840%.The measurement repeatability of crystalline lens decentration was poor, and the measurement repeatability of decentration axis, tilt and tilt axis of crystalline lens, and the repeatability of decentration and tilt of IOL were good in both eyes, with ICC range in 0.757-0.998, TRT<50% and CoV≤17.763%.There were good correlations in decentration, decentration axis, tilt and tilt axis of crystalline lens and IOL between non-mydriatic and mydriatic conditions (all r≥0.679, all at P<0.01). Conclusions:The measurement repeatability of decentration axis, tilt and tilt axis of crystalline lens and IOL, as well as the decentration of IOL by CASIA2 before and after mydriasis is good.The correlations of the measured parameters before and after mydriasis are good.

4.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20070219

RESUMEN

BackgroundThick-section CT scanners are more affordable for the developing countries. Considering the widely spread COVID-19, it is of great benefit to develop an automated and accurate system for quantification of COVID-19 associated lung abnormalities using thick-section chest CT images. PurposeTo develop a fully automated AI system to quantitatively assess the disease severity and disease progression using thick-section chest CT images. Materials and MethodsIn this retrospective study, a deep learning based system was developed to automatically segment and quantify the COVID-19 infected lung regions on thick-section chest CT images. 531 thick-section CT scans from 204 patients diagnosed with COVID-19 were collected from one appointed COVID-19 hospital from 23 January 2020 to 12 February 2020. The lung abnormalities were first segmented by a deep learning model. To assess the disease severity (non-severe or severe) and the progression, two imaging bio-markers were automatically computed, i.e., the portion of infection (POI) and the average infection HU (iHU). The performance of lung abnormality segmentation was examined using Dice coefficient, while the assessment of disease severity and the disease progression were evaluated using the area under the receiver operating characteristic curve (AUC) and the Cohens kappa statistic, respectively. ResultsDice coefficient between the segmentation of the AI system and the manual delineations of two experienced radiologists for the COVID-19 infected lung abnormalities were 0.74{+/-}0.28 and 0.76{+/-}0.29, respectively, which were close to the inter-observer agreement, i.e., 0.79{+/-}0.25. The computed two imaging bio-markers can distinguish between the severe and non-severe stages with an AUC of 0.9680 (p-value< 0.001). Very good agreement ({kappa} = 0.8220) between the AI system and the radiologists were achieved on evaluating the changes of infection volumes. ConclusionsA deep learning based AI system built on the thick-section CT imaging can accurately quantify the COVID-19 associated lung abnormalities, assess the disease severity and its progressions. Key ResultsA deep learning based AI system was able to accurately segment the infected lung regions by COVID-19 using the thick-section CT scans (Dice coefficient [≥] 0.74). The computed imaging bio-markers were able to distinguish between the non-severe and severe COVID-19 stages (area under the receiver operating characteristic curve 0.968). The infection volume changes computed by the AI system was able to assess the COVID-19 progression (Cohens kappa 0.8220). Summary StatementA deep learning based AI system built on the thick-section CT imaging can accurately quantify the COVID-19 infected lung regions, assess patients disease severity and their disease progressions.

5.
Journal of Chinese Physician ; (12): 546-550, 2018.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-705866

RESUMEN

Objective To induce a novel temperate bacteriophage from staphylococcus haemolyticus strain SA98,observe the morphology and size,complete the whole genome sequencing,analyse the structure of genome and evolutionary relationship.Methods The mitomycin C was used to induce the temperate phage from staphylococcushaemolyticus strain SA98,the induced phage was observed by transmission electron microscopy after be concentrated and purified.The genome DNA was extracted and high through sequenced.The feature of whole genome and evolutionary relationship was analyzed.Results A temperate phage IME-SA4 was successfully induced from staphylococcus haemolyticus strain SA98.Transmission electron microscopy analysis indicated that IME-SA4 had an isometric head and a non-contractile long tail.The whole genome of IME-SA4 was long as 41 843 bp,and the whole genome blast result indicated IME-SA4 shared only 13% homology with most related strain phiRS7.Conclusions A novel staphylococcus haemolyticus temperate phage with low homology with other staphylococcusphages was successfully induced from staphylococcus haemolyticus strain SA98.The research of its morphology,whole genome sequencing and comparative genome analysis make the foundation for further study of staphylococcus phages' properties and practical application.

6.
China Journal of Endoscopy ; (12): 15-17, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-612190

RESUMEN

Objective To evaluate the value of utility of bronchoscopy in human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) patients with Bacteria sputum negative pulmonary tuberculosis.Methods Bronchoscopy was conducted to 65 AIDS patients with bacteria sputum negative pulmonary tuberculosis in the first hospital of Changsha. The patients’ bronchoalveolar lavage fluid through the electronic bronchoscopy, mycobacterium tuberculosis (MTB) culture, brushings and biopsy pathology were analyzed.Results 65 cases, bronchoscope alveolar lavage lfuid smear positive acid-fast stain 14 cases (21.54%), BAL mycobacterium tuberculosis culture positive 20 cases (30.76%), a bronchoscope brush positive 24 cases (36.92%), 35 cases of bronchoscopy biopsy, according to the performance under the bronchoscope positive 21 cases (60.00%), bronchoscopy combined different methods conifrmed 43 cases (66.15%).Conclusions Bronchoscopy in AIDS with bacteria sputum negative pulmonary tuberculosis diagnosis, it has important application value.

7.
Tianjin Medical Journal ; (12): 426-429, 2016.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-486433

RESUMEN

Objective To observe the effects of different concentrations of SB203580, the inhibitor of P38MAPK, in process of high glucose (GS)-induced renal tubular epithelial-myofibroblast transdifferentiation (TEMT). Methods The cultured human renal tubular epithelial cells (HK-2) were divided into control group (5.5 mmol/L GS), GS (30 mmol/L GS) group and different concentrations of SB203580 (30 mmol/L GS +5, 10, 20 and 30 μmol/L SB203580) groups. The treat?ments were for 48 hours. MTT assay was used to observe cell proliferation. The median inhibiting concentration (IC50) was cal?culated. Western blot assay was used to detect the expressions of P38MAPK, P-P38MAPK andα-smooth muscle actin (α-SMA) in control group, high-glucose group and S30 group. The expression ofα-SMA was also detected by the method of im?munofluorescence. Results 1.Compared with control group, there was no significant inhitory effect on proliferation rate in DMSO group (P>0.05). There were increased HK-2 cells in high glucose group and S5group (P0.05). 3. Compared with control group, the expression ofα-SMA was signifi?cantly increased in high glucose group and S30 group (P<0.05). Compared with high glucose group, the expression of α-SMA was significantly decreased in S30 group (P < 0.05). Conclusion The 30 mmol/L GS can lead to TEMT in HK-2 cells. The more suitable inhibitory concentration of SB203580 in the process of TEMT is 30μmol/L. SB203580 can slow down the process of TEMT by inhibiting P38MAPK activation and inhibiting proliferation and the expression ofα-SAM s of HK-2 cells.

8.
Chinese Journal of Nephrology ; (12): 50-55, 2016.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-488924

RESUMEN

Objective To explore the effect and the possible pathway of different concentrations of QLT0267,which was the inhibitor of the integrin-linked kinase (ILK),on the process of high glucose-induced tubularepithelial-myofibroblast transdifferentiation (TEMT) in human renal tubular epithelial cells (HK-2).Methods HK-2 cells were exposed to 30 mmol/L GS,and TEMT model was established.After excluding the effect of high osmotic in TEMT,HK-2 cells were divided into 6 groups by different concentrations of GS and QLT0267 for 48 hours.The rate of the cell proliferation was calculated by MTT.The expression of ILK and α-smooth muscle actin (α-SMA) were determined by immunofluorescence and Western blot,and the expression of protein kinase B (AKT),phosphorylated protein kinase B (p-AKT),and E-cadherin were determined by Western blot.Results (1) The expression of ILK,p-AKT,and α-SMA in HK-2 cells were unregulated and the expression of E-cadherin was downregulated for 48 hours with glucose treating vs control (P < 0.05);(2) The proliferation rate in high glucose group was higher than the group which concentration of QLT0267 was greater than 5 μmol/L (P < 0.05);(3) With the concentrations of QLT0267 increased,the expression of p-AKT,α-SMA was gradually decreased (all P < 0.05),and the expression of E-cadherin was gradually increased (all P < 0.05).Conclusions 30 μmol/L of GS can lead to TEMT in HK-2 cell.The QLT0267 with concentration greater than 5 μmol/L may prevent the activation of ILK downstream proteins,then partially inhibits cell proliferation and TEMT in HK-2 cell.

9.
Tianjin Medical Journal ; (12): 1089-1092, 2015.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-478698

RESUMEN

Objective To investigate the effects of 1,25-dihydroxyvitamin D3[1,25 (OH)2D3] on cell proliferation in hu?man glomerular mesangial cells and it′s effects on the regulation of mTOR/p70s6K signaling pathway in this cell line. Meth?ods The cultured human mesangial cells at passage 3-7 were divided into four groups:control group,VD group (addition of 10-8 mol/L of 1,25-dihydroxyvitamin D3 ),R group (addition of 5 mg/L of rapamycin) and R+VD group(addition of 5 mg/L ra?pamycin combined with 10-8 mol/L of 1,25-dihydroxyvitamin D3). Drug incubation last 48 h. The effect of mesangial cell pro?liferation was measured by CCK-8 colorimetric assay. The cell cycles were measured by flow cytometry. The expression of mTOR and p70s6K were detected by immunofluorescence. Results (1) The absorbance of A450 was higher in control group than that in VD group than that in R group than that in R+VD group. But the inhibition rate (IR) was lower in control group than that in VD group than that in R group than that in R+VD group. All comparisons were of statistic significance. ( 2) Cells in G1 phase were higher while cells in G2/M and S phases as well as proliferation rate (PI) were lower in control group than those in VD group than those in R group than those in R+VD group. All comparisons were of statistic significance except in?dexes between group R and group VD. (3) mTOR and p30s6K expressions in mesangial cells were higher in control group than those in VD group than those in R group than those in R+VD group. All comparisons were of statistic significance ex?cept indexes between group R and group VD. Conclusion 1,25-dihydroxyvitamin D3 might inhibit mesangial cell prolifera?tion significantly through mTOR/p70s6K signaling pathways.

10.
Chongqing Medicine ; (36): 4387-4389, 2013.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-440150

RESUMEN

Objective Through observing and treating the ovulation dysfunction patients with birth demand ,to study the clinic characteristics and therapy strategy .Methods 630 clinical cases including natural cycles and controlled ovarian stimulated cycles . monitored by transvaginal B-ultrasonography from April 2008 to April 2012 ,The common reasons ,clinical manifestation ,and out-come undergoing different treatment strategies were analyzed .Results In the natural cycles ,41 .61% patients suffered ovulation dysfunction ,PCOS patients occupied the most .Through the therapy of controlled ovarian stimulating on these patients ,60 .84% of ovulation dysfunction patients recovered normal ovulation .The therapeutic regimen of clomiphene citrate (CC) 50 mg and of CC combined with human menopausal gonadotropin(HMG) showed a higher ovulation rate ,66 .49% and 67 .57% respectively(P<0 .05) .Anovulia was the most commonly type of the ovulation dysfunction ,followed small follicle ovulation and luteinizing unrup-tured follicle .Conclusion Ovulation dysfunction is frequent in infertility patients .Understanding the clinical characteristic and the disease cause ,working out the favourable and effective therapeutic regimen can increase their conception possibility .

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