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1.
Int Immunopharmacol ; 101(Pt A): 108167, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34607232

RESUMO

BACKGROUND: Sepsis is a systemic inflammatory response syndrome, associated with high risk of acute kidney injury (AKI) and in-hospital mortality. Thymosin beta-4 (Tß4) is an actin-sequestering protein that can prevent inflammation in several tissues. Thus, we studied the role of Tß4 in sepsis. METHODS: The Tß4 concentrations were prospectively measured in 191 patients within 6 h of the intensive care units (ICU) admission with diagnosis of sepsis. The cohort was divided into Tß4 concentration tertiles: 1.19-7.11 ng/ml (n = 64), 7.12-11.01 ng/ml (n = 64), and 11.02-28.10 ng/ml (n = 63). RESULTS: Of 191 patients, 92 patients developed AKI, 24 of whom received continuous renal replacement therapy (CRRT), 29 patients died within 7 days, and 53 patients died within 28 days. Lower Tß4 stages were correlated with poor prognosis, including AKI(odds ratio [OR], 2.102 per stage lower; 95% confidence interval [CI], 1.448 to 3.050; P < 0.001), CRRT(OR, 2.346 per stage lower; 95% CI, 1.287 to 4.276; P = 0.005), 7-day mortality(OR, 1.755 per stage lower; 95% CI, 1.050 to 2.935; P = 0.032), and 28-day mortality(OR, 1.821 per stage lower; 95% CI, 1.209 to 2.743; P = 0.004). Kaplan-Meier analysis also demonstrated that patients with lower Tß4 stages had a high risk of AKI and death. In addition, the area under the curve (AUC) of Tß4 for predicting AKI, CRRT, 7-day mortality, and 28-day mortality were, respectively, 0.702 (95% CI 0.628-0.776), 0.717 (95% CI 0.592-0.842), 0.694 (95% CI 0.579-0.808), and 0.682 (95% CI 0.598-0.767). CONCLUSIONS: Lower Tß4 stages are associated with higher odds of poor prognosis in ICU patients with sepsis.

2.
Eur Spine J ; 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34668050

RESUMO

OBJECTIVE: The aim of the study was to compare total en bloc spondylectomy (TES) and separation surgery with postoperative stereotactic radiosurgery (SSRS) for isolated metastatic patients with spinal cord compression by assessing recurrence-free survival (RFS), overall survival (OS), postoperative complications, and quality of life scores (QoL). METHODS: From October 2013 to December 2020, 52 isolated spinal metastasis patients with cord compression were selected and separated into two groups based on the surgical method used (TES group, n = 26; and SSRS group, n = 26). Indexes for evaluation included postoperative Frankel grade, postoperative ECOG-PS, RFS, OS, postoperative complications, operation time, intraoperative blood loss, and QoL. RESULTS: The average follow-up duration was 31.44 months. There was no significant difference (P > 0.05) in postoperative complications and OS between the two groups. However, a significant difference in operation time, intraoperative blood loss, postoperative ECOG-PS, RFS, and mental health domain (6 months after surgery) was found between the two groups (P < 0.05). According to The Spine Oncology Study Group Outcomes Questionnaire assessment, the total pain and physical function domains scores were also elevated after surgery in both groups. However, no significant difference was observed between groups A and B (p = 0.450 and 0.446, respectively). CONCLUSIONS: TES and SSRS were efficient methods for treating solitary spinal metastasis patients with metastatic spinal cord compression. Better local tumor control and mental health were found in the TES group, and most patients felt as if they were free of spinal tumors. Compared with TES, the SSRS caused less operation-related trauma. However, there was no significant difference in OS between the two groups.

3.
J Econ Entomol ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34546358

RESUMO

Uridine diphosphate glucosyltransferases (UGTs), which are phase II detoxification enzymes, are found in various organisms. These enzymes play an important role in the detoxification mechanisms of plant allelopathy and in insects. Artemisia vulgaris L. (Asterales: Asteraceae: Artemisia) essential oil has strong contact toxicity to Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) larvae. However, the effect of A. vulgaris essential oil on UGTs is unclear. In this study, A. vulgaris essential oil was shown to significantly induce the expression of the TcUgt86Dg transcript. Furthermore, treatment of TcUgt86Dg-silenced individuals with A. vulgaris essential oil resulted in higher mortality than for the control individuals, indicating that TcUgt86Dg is involved in detoxification of A. vulgaris essential oil in T. castaneum. The developmental expression profile showed that the expression of TcUgt86Dg in late adults was higher than in other developmental stages. Furthermore, the expression profile in adult tissues revealed higher expression of TcUgt86Dg in the head, antenna, fat body, and accessory gland than in other tissues. These data show that TcUgt86Dg may be involved in the metabolism of exogenous toxins by T. castaneum; thus, our results have elucidated one possible mechanism of resistance to A. vulgaris essential oil and provide a theoretical basis for a control scheme for T. castaneum.

4.
Sensors (Basel) ; 21(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502570

RESUMO

A novel wearable button antenna sensor is proposed for the concept of simultaneous wireless information and power transfer (SWIPT). This integrates two working modes for the transfer of power and information, respectively, and optimizes transfer efficiency. An omni-directional radiation pattern is achieved in the 3.5 GHz World Interoperability for Microwave Access (WiMAX) band to support on-body wireless communications, while a circularly polarized broadside radiation pattern is obtained in the 5 GHz wireless local area networks (WLAN) band to harvest power. The measured -10 dB return loss bandwidths are 4.0% (3.47-3.61 GHz) in the lower band, and 25.0% (4.51-5.80 GHz) in the higher band, respectively. An artificial magnetic conductor (AMC) structure with wideband characteristics is applied to obtain a low-profile design and to increase the stability of the antenna sensor. A high radiation efficiency of over 80% in the whole working band is observed. The specific absorption rate (SAR) of the proposed antenna sensor is below 0.509 W/kg at 3.55 GHz, and below 0.0532 W/kg at 5.5 GHz, respectively, which is much lower than the European standard threshold of 2 W/kg. All these characteristics make the designed antenna sensor suitable for on-body information transmission and off-body energy harvesting. The antenna sensor has been prototyped. Simulations and measurements agree well, proving the validity of the new concept.


Assuntos
Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Desenho de Equipamento , Redes Locais , Micro-Ondas
5.
Chempluschem ; 86(9): 1267-1282, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34472731

RESUMO

Phase-change materials (PCMs) play a key role in thermal energy storage owing to their high-energy storage density and small temperature fluctuation during the phase-transition stage. Polymers, either as a supporting material to prevent liquid leakage during the phase-change process or used with specific target, have been widely recognized in the fabrication of PCM composites. In the meantime, due to the continued demand for variety of PCMs, a single thermal energy storage function seems to be insufficient to meet these needs. Thanks to the good compatibility with PCMs and the structural adjustable properties of polymers, they have been broadly used as the second component in the multifunctional PCMs composite. In this Review, strategies for multifunctional PCMs supported by polymers and their potential energy applications, such as thermal energy harvesting and storage, shape memory, wearable devices, self-cleaning, and other forms of applications, are summarized comprehensively. The future research directions and challenges of multifunctional PCMs with polymers are also discussed.

6.
Comput Methods Programs Biomed ; 209: 106331, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34418813

RESUMO

BACKGROUND AND OBJECTIVE: In this study, we tried to create a machine-learning method that detects disease lesions from chest X-ray (CXR) images using a data set annotated with extracted CXR reports information. We set the nodule as the target disease lesion. Manually annotating nodules is costly in terms of time. Therefore, we used the report information to automatically produce training data for the object detection task. METHODS: First, we use semantic segmentation model PSP-Net to recognize lung fields described in the CXR reports. Next, a classification model ResNeSt-50 is used to discriminate the nodule in segmented right and left field. It also can provide attention map by Grad-Cam. If the attention region corresponds to the location of the nodule in the CXR reports, an attention bounding box is generated. Finally, object detection model Faster-RCNN was performed using generated attention bounding box. The bounding boxes predicted by Faster-RCNN were filtered to satisfy the location extracted from CXR reports. RESULTS: For lung field segmentation, a mean intersection of union of 0.889 was achieved in our best model. 15,156 chest radiographs are used for classification. The area under the receiver operating characteristics curve was 0.843 and 0.852 for the left and right lung, respectively. The detection precision of the generated attention bounding box was 0.341 to 0.531 depending on the binary setting for attention map. Through object detection process, the detection precisions of the bounding boxes were improved to 0.567 to 0.800. CONCLUSION: We successfully generated bounding boxes with nodule on CXR images based on the positional information of the diseases extracted from the CXR reports. Our method has the potential to provide bounding boxes for various lung lesions which can reduce the annotation burden for specialists. SHORT ABSTRACT: Machine learning for computer aided image diagnosis requires annotation of images, but manual annotation is time-consuming for medical doctor. In this study, we tried to create a machine-learning method that creates bounding boxes with disease lesions on chest X-ray (CXR) images using the positional information extracted from CXR reports. We set the nodule as the target lesion. First, we use PSP-Net to segment the lung field according to the CXR reports. Next, a classification model ResNeSt-50 was used to discriminate the nodule in segmented lung field. We also created an attention map using the Grad-Cam algorithm. If the area of attention matched the area annotated by the CXR report, the coordinate of the bounding box was considered as a possible nodule area. Finally, we used the attention information obtained from the nodule classification model and let the object detection model trained by all of the generated bounding boxes. Through object detection model, the precision of the bounding boxes to detect nodule is improved.


Assuntos
Diagnóstico por Computador , Neoplasias Pulmonares , Algoritmos , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Radiografia
7.
Front Pharmacol ; 12: 726528, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421620

RESUMO

Dendrobium officinale, a well-known plant used as a medicinal and food homologous product, has been reported to contain various bioactive components, such as polysaccharides, bibenzyls, phenanthrenes, and flavonoids. It is also widely used as a traditional medicine to strengthen "Yin", nourish heart, tonify five viscera, remove arthralgia, relieve fatigue, thicken stomach, lighten body, and prolong life span. These traditional applications are in consistent with modern pharmacological studies, which have demonstrated that D. officinale exhibits various biological functions, such as cardioprotective, anti-tumor, gastrointestinal protective, anti-diabetes, immunomodulatory, anti-aging, and anti-osteoporosis effects. In this review, we summarize the research progress of D. officinale from November 2016 to May 2021 and aim to better understand the botany, traditional use, phytochemistry, and pharmacology of D. officinale, as well as its quality control and safety. This work presents the development status of D. officinale, analyzes gaps in the current research on D. officinale, and raises the corresponding solutions to provide references and potential directions for further studies of D. officinale.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34360064

RESUMO

China and other emerging market countries have suffered from the problem of environmental pollution while developing rapidly in the past few decades. In recent years, many countries have introduced strict environmental regulations in order to achieve sustainable development. This paper discusses the relationship between environmental regulations and corporate green innovation from the perspective of regional leaders' promotion pressure. The empirical results show that direct policy regulation within the region stimulates green innovation on the part of enterprises, and the promotion pressure of city leaders has a further positive moderating effect on the positive correlation between environmental regulations and enterprises' green innovation. The conclusion of the study proves that a strict environmental policy can promote the effectiveness of an environmental performance appraisal system in the sustainable development plans of cities and enterprises. This paper not only reveals the influence path of official promotion pressure on the sustainable development of enterprises in the administrative area from the micro perspective but also sheds some light that may improve government governance and promote the transformation of enterprises.


Assuntos
Organizações , Desenvolvimento Sustentável , China , Cidades , Política Ambiental , Poluição Ambiental/prevenção & controle , Humanos
10.
Exp Biol Med (Maywood) ; : 15353702211028193, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233522

RESUMO

Epithelial tissue has important functions such as protection, secretion, and sensation. Epithelial damage is involved in various pathological processes. Bone morphogenetic proteins (BMPs) are a class of growth factors with multiple functions. They play important roles in epithelial cells, including in differentiation, proliferation, and migration during the repair of the epithelium. This article reviews the functions and mechanisms of the most profoundly studied BMPs in the process of epithelial damage repair and their clinical significance.

11.
BMC Cardiovasc Disord ; 21(1): 274, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34088274

RESUMO

BACKGROUND: The morning blood pressure surge (MBPS) is related to an exaggerated risk of cardiovascular diseases and mortality. With increasing attention on circadian change in blood pressure and extensive use of ambulatory blood pressure monitoring (ABPM), chronotherapy that administration of medication according to biological rhythm, is reported to improve cardiovascular outcomes. The aim of this study is to evaluate the influence of chronotherapy of antihypertensive drugs upon MBPS in hypertensive patients. METHODS: A search strategy was applied in Ovid MEDLINE, EMBASE, Cochrane (Wiley) CENTRAL Register of Controlled Trials, Cochrane Database of Systematic Reviews, and the Chinese Biomedical literature database. No language and date restrictions. Randomized controlled trials (RCT) assessing the efficacy of evening and morning administration of the same medications in adult patients with primary hypertension were included. RESULTS: A total of ten trials, comprising 1724 participants with a mean age of 61 and 51% female, were included in this study. Combined analysis observed significant reduction of MBPS (- 5.30 mmHg, 95% CI - 8.80 to - 1.80), night-time SBP (- 2.29 mmHg, 95% CI - 4.43 to - 0.15), night-time DBP (- 1.63 mmHg, 95 %CI - 3.23 to - 0.04) and increase in night blood pressure dipping (3.23%, 95% CI 5.37 to 1.10) in evening dosage compared with traditional morning dosage of blood pressure-lowering drugs. No significant difference was found in the incidence of overall adverse effects (RR 0.65, 95% CI 0.30 to 1.41) and withdrawal due to adverse effects (RR 0.95, 95% CI 0.53 to 1.71). CONCLUSIONS: Our study suggested that evening administration of antihypertensive medications exerted better blood pressure-lowering effect on MBPS compared with conventional morning dosage. Safety assessment also indicated that the evening regimen did not increase the risk of adverse events. However, endpoint studies need to be carried out to confirm the significance and feasibility of this treatment regimen in clinical practice.

12.
Blood Cells Mol Dis ; 90: 102588, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34166998

RESUMO

We present data from our study of plerixafor mobilization (NCT02193191) relevant to the question of whether further dose escalation of plerixafor can address inconsistent adequacy of CD34+ mobilization for gene therapy of sickle cell disease (SCD). We found that, in the same patient, higher plerixafor dosing was associated with higher fold increases in PB CD34+ count, but not necessarily higher absolute CD34+ counts. Variation in pre-apheresis absolute CD34+ counts was related to intra-individual variation in baseline PB CD34+ counts and inter-individual variation in responsiveness to plerixafor. Overall, our results support further studies of continued dose escalation of plerixafor for autologous HPC collection in SCD.

13.
Virus Evol ; 7(1): veab046, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34141450

RESUMO

Multiple recent outbreaks of highly pathogenic H5N8 viruses originating in aquatic birds frequently occurred in most European countries, Russia, South Korea, and Japan during the winter of 2020-21, and one zoonotic event of poultry workers infected with novel H5N8 viruses were reported in Russia. Strikingly, these novel H5N8 viruses had emerged and been co-circulating in wild birds and poultry in multiple provinces of China during 2020-21. In China, the population of aquatic birds has risen significantly in the past twenty years, and China is regarded as the largest reservoir for influenza viruses carried in aquatic birds across the globe. Hence, the co-circulation of these novel H5N8 viruses poses an alarming threat to not only poultry industry but also human health. In this study, we sequenced full-length genomes of these H5N8 viruses circulating in China. Phylogenetic analysis demonstrated that poultry-origin H5N8 viruses in China fell within wild birds-origin clade 2.3.4.4b H5N8 viruses from Europe during 2020-21, and notably, were genetically closely related to human-infecting H5N8 viruses in Russia. Moreover, they possessed several molecular markers associated with mammalian adaption. Bayesian coalescent analysis showed that these H5N8 viruses might have introduced into China during June-September 2020, suggesting that these H5N8 viruses might have introduced via wild bird migration or poultry trade. Besides, we also found that the effective population size of clade 2.3.4.4b H5N8 viruses dramatically increased during the winter season of 2020/21, as is consistent with previous increase of genetic diversity during the winter seasons of 2013/14 and 2016/17, which indicated that the wild bird migration accelerates the genetic diversity of these H5N8 viruses during the winter season of 2020/21. Notably, these novel H5N8 viruses were lethal to chickens and mice, highly transmissible to ducks, and were antigenically distinct from 2.3.4.4h H5 viruses circulating in China, posing considerable threats to public health. Our findings offer novel insights into the evolution and risk assessment of H5N8 viruses during the winter season of 2020-21.

14.
Mitochondrial DNA B Resour ; 6(7): 1937-1938, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34179473

RESUMO

The complete plastid genome of Chrysanthemum morifolium 'Orizaba', a cultivar from Holland, was determined and analyzed in this work. It is a circular chromosome and has a length of 151,060 bp. The LSC and SSC of 82,858 bp and 18,294 bp were separated by two IRs of 24,954 bp. The chloroplast genome of C. morifolium 'Orizaba' contains 125 genes, including 83 protein-coding genes, eight ribosomal RNA genes, and 34 transfer RNA genes. Phylogenetic analysis showed that C. morifolium 'Orizaba' clustered together with other Chrysanthemum varieties in the family Asteraceae. The plastome is useful for the elucidation of phylogenetics and evolution in the Asteraceae and Chrysanthemum varieties.

15.
Acta Biomater ; 131: 262-275, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34157451

RESUMO

Decellularized extracellular matrix (dECM) hydrogels are being increasingly investigated for use in bio-inks for three-dimensional cell printing given their good cytocompatibility and biomimetic properties. The osmotic pressure and stiffness of bio-ink are important factors affecting the biological functions of printed cells. However, little attention has been given to the osmotic pressure and stiffness of the dECM bio-inks. Here, we compared three types of commonly used acidic solutions in the bio-fabrication of a tendon derived dECM bio-ink for 3D cell printing (0.5 M acetic acid, 0.1 M hydrochloric acid and 0.02 M hydrochloric acid). We found that low pH value of 0.1 M hydrochloric acid could accelerate the digestion process for dECM powders. This could lead to a much softer dECM hydrogel with storage modulus less than 100 Pa. This soft dECM hydrogel facilitated the spreading and proliferation of stem cells encapsulated within it. It also showed better tendon-inducing ability compared with two others much stiffer dECM hydrogels. However, this over-digested dECM hydrogel was more unstable as it could shrink with the culture time going on. For 0.5 M acetic acid made dECM bio-ink, the hyperosmotic state of the bio-ink led to much lower cellular viability rates. Postprocess (Dilution or dialysis) to tailor the osmotic pressure of hydrogels could be a necessary step before mixed with cells. Thus, kindly choosing the type and concentration of acidic solution is necessary for dECM bio-ink preparation. And a balance should be made between the digestion period, strength of acidic solution, as well as the size and concentration of the dECM powders. STATEMENT OF SIGNIFICANCE: The dECM bio-ink has been widely used in 3D cell printing for tissue engineering and organ modelling. In this study, we found that different types of acid have different digestion and dissolution status for the dECM materials. A much softer tendon derived dECM hydrogel with lower stiffness could facilitate the cellular spreading, proliferation and tendon differentiation. We also demonstrated that the osmotic pressure should be taken care of in the preparation of dECM bio-ink with 0.5 M acetic acid. Thus, kindly choosing the type and concentration of acidic solution is necessary for dECM bio-ink preparation.


Assuntos
Matriz Extracelular , Tinta , Hidrogéis/farmacologia , Impressão Tridimensional , Tendões , Engenharia Tecidual , Tecidos Suporte
16.
Opt Express ; 29(11): 16323-16333, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154198

RESUMO

In order to stabilize the extinction cross section measurement of a single nanoparticle, we propose to analyze the blurriness parameter of aperture edge images in real time, which provides a feedback to lock the sample position. Unlike the conventional spatial modulation spectroscopy (SMS) technique, a probe beam experiences both the spatial modulation by a piezo stage and the temporal modulation by a chopper. We experimentally demonstrate that the measurement uncertainty is one order magnitude less than that in the previous report. The proposed method can be readily implemented in conventional SMS systems and can help to achieve high stability for sensing based on light extinction by a single nanoparticle, which alleviate the impact from laboratory environment and increase the experimental sensitivity.

17.
Sci Rep ; 11(1): 12817, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140554

RESUMO

Aimed at the problem that the quality of the formation of aero-rotor blades with complex shaped structures is difficult to predict due to the coupling of each physical field in the process of electrochemical machining, a mathematical model of electrochemical machining characterized by the conductivity of the multi-physics field is established firstly by studying the coupling action mechanism of the flow field and temperature field on electric field conductivity in the machining process. Then, utilizing the Runge-Kutta method, the relationship between the conductivity and the machine path is analysed; Finally, based on this relationship, the multi-physics field electrochemical machining erosion model is compared with the traditional single electric field electrochemical machining erosion model. The results show that the error of the multi-physical field coupling prediction model proposed in this study is in the range of 1.27-2.35%, while the accuracy of the single electric field prediction model is in the range of 4.35-5.88%. The theoretical value of the multi-physics field coupling simulation is closer to the measured value of the test and can accurately simulate the actual electrochemical machining process, which can provide a theoretical basis for the design of cathode tools and parameter optimization in the actual processing process and is of great significance to improve the quality and efficiency of the electrochemical machining of aero-rotor blades.

18.
Acta Cir Bras ; 36(4): e360403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008744

RESUMO

PURPOSE: To study effects of Rehmannia glutinosa polysaccharides (RGP) on bone tissue structure and skeletal muscle atrophy in rats with disuse. METHODS: A rat model of disuse osteoporosis combined with muscle atrophy was established by removing the bilateral ovaries of rats and fixing their hind limbs for a long time. Forty SD rats were administered intragastrically for 12 weeks. The bone histomorphometry parameters and the level of oxidative stress were measured. In addition, the changes of muscle atrophy F-box (MAFbx), muscle RING-finger protein-1 (MuRF1), forkhead box O1 (FOXO1) mRNA expression in skeletal muscle of rats were observed. RESULTS: RGP significantly increased the percentage of fluorescence perimeter and bone mineralization deposition rate of the second lumbar vertebrae of rats. It also significantly increased the wet weight ratio and muscle fiber cross-sectional area of the gastrocnemius muscle of rats. At the same time, RGP significantly increased the levels of super oxide dismutase (SOD) and catalase (CAT) in the skeletal muscle of rats, and reduced the content of malondialdehyde (MDA). Rehmannia glutinosa polysaccharides also significantly reduced the expression levels of FOXO1, MAFbx and MuRF1 mRNA in rat skeletal muscle. CONCLUSIONS: RGP could improve the bone structure of osteoporotic rats. It could also improve muscle that atrophy may be related to the inhibition of FOXO1-mediated ubiquitin-proteasome pathway.


Assuntos
Rehmannia , Animais , Osso e Ossos , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Polissacarídeos/farmacologia , Ratos , Ratos Sprague-Dawley
19.
Int Orthop ; 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34041582

RESUMO

PURPOSE: Our research developed a novel approach to quantitatively evaluate the boundary of necrotic lesions in osteonecrosis of the femoral head (ONFH) and to explore its diagnostic value in predicting bone collapse of the femoral head. METHODS: A retrospective cross-sectional study was conducted in our institution, and 146 hips (121 cases) identified as ONFH were recruited. The anterior and lateral boundaries of each enrolled subject were measured in standard anteroposterior (AP) view and frog-leg (FL) view of plain radiographic images, the intact rate of which was then calculated and presented as the anteroposterior view intact ratio (APIR) and frog-leg view intact ratio (FLIR), respectively. Univariate and multivariate logistic regression analyses were performed to identify risk factors for collapse. A receiver operating characteristic (ROC) curve analysis was performed to determine the sensitivity, specificity and cutoff value of the APIR and FLIR. A Kaplan-Meier (K-M) analysis was applied to calculate the survival rate of the femoral head, and bone collapse of the femoral head was regarded as the endpoint. RESULTS: Femoral head collapse was observed in 61 hips during the follow-up period. Patients with or without femoral head collapse were categorized into the collapse group and non-collapse group, respectively. The mean follow-up time was 3.7 years (2-9) for the collapse group and 7.7 years (5-20) for the non-collapse group. Univariate and multivariate logistic regression analysis and ROC analysis showed that APIR (< 25.61%) and FLIR (< 24.43%) were significantly associated with femoral head collapse. The K-M survival curves indicated that the overall survival rate of APIR (≥ 25.61%) was 94.8% at 7.5 years and 76.6% at 10 years, while that of FLIR (≥ 24.43%) was 87.3% at 7.5 years and ten years. CONCLUSION: The present study demonstrates that APIR and FLIR are of high diagnostic value in the early and middle stages of ONFH. APIR and FLIR can be used to predict the occurrence of femoral head collapse in patients with JIC classification types B and C1. The measurement of these two parameters in plain radiography images may contribute to the selection of a proper hip preservation strategy.

20.
Arthroscopy ; 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34052387

RESUMO

PURPOSE: To investigate the kinematics differences between round-tunnel (ROT) and flat-tunnel (FLT) techniques in anterior cruciate ligament (ACL) reconstruction when using hamstring graft. METHODS: Nine matched pairs of fresh-frozen cadaveric knees were evaluated for the kinematics of intact, ACL-sectioned, and either ROT or FLT reconstructed knees. The graft bundles for FLT technique were separately tensioned. A 6 degrees of freedom robotic system was used to assess knee laxity: (1) 134-N anterior tibial load at 0°, 15°, 30°, 60°, and 90°of knee flexion; (2) 10 Nm of valgus torque followed by 5 Nm of internal rotation torque simulates a pivot-shift test at 15° and 30°; (3) 5-Nm internal and external rotation torques at 0°, 15°, 30°, 60°, and 90°; (4) 10-Nm varus and valgus torques at 15° and 30°. RESULTS: Significant differences were found for ROT versus FLT techniques in terms of the simulated pivot-shift test at 15° (2.5 mm vs 1.4 mm, respectively, difference from intact; P =.039) and the internal rotation test at 15° (2.5° vs 0.5°, respectively, difference from intact; P =.034) and 30° (2.0° vs 0.4°, respectively, difference from intact; P =.014). No significant differences were found between groups during 134-N anterior tibial load, external rotation and valgus/varus rotation. Neither technique was able to reproduce the intact state during an anterior tibial load and simulated pivot-shift test. CONCLUSIONS: The FLT technique with independently tensioned bundles shows the same anterior control as the ROT technique but better restores rotational stability in terms of the simulated pivot-shift test and the internal rotation test in anatomic ACL reconstruction at time zero. CLINICAL RELEVANCE: The FLT technique with independently tensioned bundles of ACL reconstruction appears to be a viable, more anatomic technique than the ROT technique in mimicking flat anatomy and rotational stability of native ACL.

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