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1.
Phytother Res ; 37(9): 3939-3950, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37114508

RESUMO

The present study aimed to evaluate anti-rheumatoid arthritis (RA) effect of Lonicerin (LON), a safe compound with anti-inflammatory and immunomodulatory properties. Nevertheless, the exact role of LON in RA remains elusive. In this test, the anti-RA effect of LON was evaluated in collagen-induced arthritis (CIA) mouse model. Relevant parameters were measured during the experiment; ankle tissue and serum were collected at the end of the experiment for radiology, histopathology, and inflammation analysis. ELISA, qRT-PCR, immunofluorescence, and western blot were used to explore the effect of LON on the polarization of macrophages and related signal pathways. It was discovered that LON treatment attenuated the disease progression of CIA mice with lower paw swelling, clinical score, mobility, and inflammatory response. LON treatment significantly decreased M1 marker levels in CIA mice and LPS/IFN-γ-induced RAW264.7 cells, while slightly increasing M2 marker levels in CIA mice and IL-4-induced RAW264.7 cells. Mechanistically, LON attenuated the activation of the NF-κB signaling pathway, which contributes to M1 macrophage polarization and inflammasome activation. In addition, LON inhibited NLRP3 inflammasome activation in M1 macrophages, thereby reducing inflammation by inhibiting IL-1ß and IL-18 release. These results indicated that LON might exert anti-RA effects by regulating the polarization of M1/M2 macrophage, especially by inhibiting macrophage polarization toward M1.


Assuntos
Artrite Experimental , Artrite Reumatoide , Camundongos , Animais , NF-kappa B/metabolismo , Artrite Experimental/tratamento farmacológico , Inflamassomos/metabolismo , Macrófagos , Transdução de Sinais , Artrite Reumatoide/tratamento farmacológico , Inflamação/metabolismo
2.
Clin Orthop Relat Res ; 479(10): 2228-2235, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33787525

RESUMO

BACKGROUND: Teleradiology has become one of the most important approaches to virtual clinical diagnosis; its importance has only grown during the coronavirus 2019 pandemic. In developing countries, asking patients to take photographs of their images using a smartphone can facilitate the process and help keep its costs down. However, the images taken by patients with smartphones often are of poor quality, and there is no regulation or standard instruction about how to use smartphones to take photographs of medical examination images effectively. These problems limit the use of smartphones in remote diagnosis and treatment. QUESTIONS/PURPOSES: To formulate a set of guidelines for the most appropriate and effective use of smartphones to capture images (radiographs, CT images, and MR images), and to determine whether these guidelines are more effectively adopted by patients of differing ages and genders. METHODS: In this prospective study, a set of step-by-step instructions was created with the goal of helping patients take better smartphone photographs of orthopaedic diagnostic images for transfer to telemedicine services. Following the advice of surgeons, experts in smartphone technology, imaging experts, and suggestions from patients, the instructions were modified based on clinical experience and finalized with the goals of simplicity, clarity, and convenience. Potentially eligible patients were older than 18 years, had no cognitive impairment, and used smart phones. Based on that, 256 participants (patients or their relatives and friends) who visited the orthopaedic department of our hospital from June to October 2020 potentially qualified for this study. A total of 11% (29) declined to participate, leaving 89% (227) for analysis here. Their mean age was 36 ± 11 years, 50% were women (113 of 227), and the patient himself/herself represented in 34% (78 of 227) of participants while relatives or friends of patients made up 66% (149 of 227) of the group. In this study, the diagnoses included spinal stenosis (47% [107 of 227]), disc herniation without spinal stenosis (31% [71 of 227]), vertebral fractures (14% [32 of 227]), and other (7% [17 of 227]). Each study participant first took photographs of their original medical images based on their own knowledge of how to use the smartphone camera function; each participant then took pictures of their original images again after receiving our instructional guidance. Three senior spine surgeons (YZ, TQL, TCM) in our hospital analyzed, in a blinded manner, the instructed and uninstructed imaging files based on image clarity (the content of the image is complete, the text information in the image is clearly visible, there is neither reflection nor shadow in the image) and image position (it is not tilted, curled, inverted, or reversed). If either of these conditions was not satisfied, the picture quality was deemed unacceptable; two of three judges' votes determined the outcome. Interobserver reliability with kappa values for the three judges were 0.89 (YZ versus TQL), 0.92 (YZ versus TCM), and 0.90 (TQL versus TCM). RESULTS: In this study, the overall proportion of smartphone medical images deemed satisfactory increased from 40% (91 of 227) for uninstructed participants to 86% (196 of 227) for instructed participants (risk ratio 2.15 [95% CI 1.82 to 2.55]; p<0.001). The proportion of acceptable-quality images in different age groups improved after instruction, except for in patients aged 51 years or older (3 of 17 uninstructed participants versus 8 of 17 instructed participants; RR 2.67 [95% CI 0.85 to 8.37]; p = 0.07). The proportion of acceptable-quality images in both genders improved after instruction, but there was no difference between the genders. CONCLUSION: We believe our guidelines for patients who wish to take smartphone photographs of their medical images will decrease image transmission cost and facilitate orthopaedic telemedicine consultations. However, it appears that patients older than 50 years are more likely to have difficulty with this approach, and if so, they may benefit from more hands-on assistance from clinic staff or younger relatives or friends. The degree to which our findings are culture-specific should be verified by other studies in other settings, but on the face of it, there is little reason to believe our findings would not generalize to a reasonable degree. Other studies in more heterogeneous populations should also evaluate factors related to levels of educational attainment and wealth differences, but in the meantime, our findings can give clinical teams an idea of which patients may need a little extra assistance. LEVEL OF EVIDENCE: Level II, therapeutic study.


Assuntos
Diagnóstico por Imagem/normas , Fotografação/normas , Smartphone/normas , Telerradiologia/normas , Adulto , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Prospectivos , SARS-CoV-2
3.
Neural Plast ; 2020: 8842110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299396

RESUMO

Musculoskeletal pain (MSP) is one of the most severe complaints in women undergoing menopause. The prevalence of MSP varied when taking the menopausal state and age factor into consideration. This study investigated the prevalence of MSP in perimenopausal women and its association with menopausal state. The MEDLINE, Embase, Web of Science, and PubMed databases were searched from inception to July 2020, and 16 studies were retrieved for the current meta-analysis. The primary outcome measure was the MSP Odds Ratio (OR). The estimated overall prevalence of MSP among perimenopausal women was 71% (4144 out of 5836, 95% confidence interval (CI): 64%-78%). Perimenopausal women demonstrated a higher risk for MSP than premenopausal ones (OR: 1.63, 95% CI: 1.35-1.96, P = 0.008, I 2 = 59.7%), but similar to that in postmenopausal ones (OR: 1.07, 95% CI: 0.95-1.20, P = 0.316, I 2 = 13.4%). The postmenopausal women were at a higher risk of moderate/severe MSP than the premenopausal ones (OR: 1.45, 95% CI: 1.21-1.75, P = 0.302, I 2 = 16.5%) or the perimenopausal ones (OR: 1.40, 95% CI: 1.09-1.79, P = 0.106, I 2 = 55.4%). In conclusion, the perimenopause is a state during which women are particularly predisposed to develop MSP. As to moderate to severe degrees of MSP, the odds increase linearly with age, from premenopause to peri- and then to postmenopause.


Assuntos
Menopausa/fisiologia , Dor Musculoesquelética/fisiopatologia , Perimenopausa/fisiologia , Pré-Menopausa/fisiologia , Humanos , Dor Musculoesquelética/epidemiologia , Pós-Menopausa/fisiologia , Prevalência
4.
Ann Plast Surg ; 84(5S Suppl 3): S165-S170, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32282414

RESUMO

OBJECTIVE: This study aimed to present the use of flow-through free anterolateral thigh (ALT) flap for the reconstruction of severe limb injury. PATIENTS AND METHODS: Four patients (2 male and 2 female subjects), with an average age of 26 (9-39) years, were included. These injuries referred to upper and lower limbs, including bone, soft tissue, nerve, and arterial segments. Two patients experienced large soft tissue defects in the lower limb and were repaired by double flow-through ALT flaps. The sizes of damaged soft tissues in the remaining 2 patients were 14 × 10 cm and 21 × 13 cm, respectively. Three patients had bone fractures, in which one of them experienced bone shortening during operation. The arterial injury was observed in 2 patients and the lengths of defects were 5 and 12 cm, respectively. Flow-through free ALT flap was applied for all 4 patients. RESULTS: Patients were followed up for 18 months. All the flaps have survived successfully without any vascular crisis or infection. All incision wounds were under primary healing stage, without any severe complications. The flaps showed better appearance, color, texture, and satisfactory sensation. All patients had satisfactory functional recovery of their injured limbs. CONCLUSIONS: The flow-through free ALT flap assists in overcoming complex traumatic injuries with severe soft tissue and arterial defects in the limbs. This flow-through ALT flap can be an effective alternative for reconstruction of severe limb injury.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Adulto , Feminino , Humanos , Masculino , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Coxa da Perna/cirurgia , Resultado do Tratamento
5.
Med Sci Monit ; 25: 7370-7375, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31571675

RESUMO

BACKGROUND Many clinical studies have assessed the association of laminoplasty opening size (LOS) with sagittal canal diameter (SCD) based on single-door cervical laminoplasty (SDCL). Nevertheless, the "worn-off" lamina extracted in SDCL was neglected in these reports. We aimed to develop a simple mathematical model to analyze the relationship between the effective LOS and SCD, taking into consideration the worn-off lamina. MATERIAL AND METHODS A total of 106 patients treated by SDCL at our hospital were included in this study. Pre-operative and post-operative SCDs were assessed using a picture archiving and communication system (PACS) based on computed tomography scans. Mini-plate sizes as well as drill bit diameters were recorded in detail in order to determine the effective LOS for each vertebral lamina involved. RESULTS SCD in all patients was increased significantly after SDCL (P<0.01). A linear correlation was found between effective LOS and the post-operative SCD increment from C3 to C7 (R²>0.933, P<0.001). The 12 mm mini-plate was most often used in SDCL, accounting for 64.45% of all cases, whereas 10 mm and 16 mm mini-plates were the least used, accounting for 3.85% and 3.00%, respectively. CONCLUSIONS There is a strong linear correlation between effective LOS and the post-operative SCD increment. The SCD was increased by about 0.5 mm per mm increase in effective LOS. Thus, post-operative SCD could be precisely calculated and predicted, enabling the selection of optimal mini-plate prior to SDCL.


Assuntos
Vértebras Cervicais/cirurgia , Laminectomia/métodos , Laminoplastia/métodos , Placas Ósseas , China , Humanos , Modelos Teóricos , Canal Medular/cirurgia , Estenose Espinal/cirurgia
6.
Arch Phys Med Rehabil ; 100(10): 1872-1880, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30684486

RESUMO

OBJECTIVE: To assess the survival and the predictors of mortality in patients with severe cervical spinal cord injuries (CSCI). DESIGN: Retrospective study. PARTICIPANTS: From January 1, 2010, to May 31, 2018, patients who suffered from severe CSCIs in Western China were enrolled in this study (N=222). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Survival rates and mortality risk factors. Measures were calculated by the product-limit method (Kaplan-Meier) and the Cox model. RESULTS: The overall 1-year, 3-year, 5-year, and 8-year postoperative mortalities were 24.4%, 30.6%, 33.3%, 36.2%, and 39.0%, respectively. Most deaths occurred within 36 months after the injury. According to the Cox proportional hazards model, the significant predictors of survival were as follows: (1) age; (2) neurologic level; (3) treatment options (surgical or conservative); (4) ventilator support (P<.05). The 8-year mortality for older patients (>50y) was 50.2%, which was significantly higher than that for younger patients (32.4%, <50y). The risk of death was 2.053 times higher in higher levels of injury (C1-C4) than in lower levels of injury (C5-C8) (P<.05). Compared with conservative treatment, patients who received surgical treatment (either anterior or posterior decompression) had a lower risk of death (P<.05). No significant difference was detected in the risk of death between early surgery (<3d) and mid-term surgery (3-7d) (P>.05). However, patients who received late-term surgery (>7d) had a higher mortality risk (P<.05). The overall 8-year mortality risk of patients who needed ventilator support was much higher than those who did not need ventilator support (P<.05). CONCLUSIONS: Age, neurologic level, ventilator dependence, treatment options, and timing to surgery were main risk factors for mortality in patients with severe CSCIs. Better understanding of the predictors for survival could possibly contribute to the improvement of survival rates.


Assuntos
Vértebras Cervicais/lesões , Traumatismos da Medula Espinal/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Vértebras Cervicais/cirurgia , China/epidemiologia , Tratamento Conservador , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Modelos de Riscos Proporcionais , Respiração Artificial , Estudos Retrospectivos , Fatores de Risco , Traumatismos da Medula Espinal/terapia , Taxa de Sobrevida , Tempo para o Tratamento , Adulto Jovem
7.
Eur Spine J ; 28(10): 2302-2310, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31053937

RESUMO

PURPOSE: To build a mathematical model which could calculate the desired laminoplasty opening size (LOS) based on the target sagittal canal diameter (SCD) before single-door cervical laminoplasty (SDCL) when taking the effects of surgery drill into consideration. METHODS: The model was based on geometric analysis on deformation of spinal canal; the formula was derived and characterized as: y (mm) = 2 [Formula: see text] × sin(ß/2) = c - d (y is the size of LOS, [Formula: see text] the size of transverse canal diameter, ß the size of laminoplasty opening size, c the size of mini-plate and d the diameter of the drill bit used during the surgery operation). The parameters of pre- and postoperative computed tomography scans of 20 patients who had undergone SDCL were measured by the picture archiving and communication system (PACS) software and a new instrument named as Lei's ruler, respectively. RESULTS: The effects of surgery SDCL were very significant; for each patient, the SCD was enlarged dramatically after the surgery (P < 0.01). The differences between the data obtained by PACS and Lei's ruler were no statistically significant (P > 0.05). According to the derived formula, the 95% confidence intervals of SCD after the surgery were within the range of 14 mm and 14.5 mm. CONCLUSION: Applying the mathematical model and derived formula, the desired LOS could be calculated according to the target SCD which could help the surgeon select an optimum mini-plate before SDCL. At the same time, a new measuring device named Lei's ruler is designed for the convenience of the derived formula. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Vértebras Cervicais/cirurgia , Laminoplastia/métodos , Modelos Teóricos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Med Sci Monit ; 24: 7438-7443, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30334549

RESUMO

BACKGROUND The incidence of hip fracture is steadily increasing. We aimed to establish a creative approach to precisely estimate the risk of hip fracture by exploring the relationship between hip fracture and bone mineral density (BMD)/femur geometry. MATERIAL AND METHODS Sixteen samples of cadaveric female proximal femora were randomly selected. Experiments were performed experimental measurement of the femoral neck BMD and geometric parameters (including neck length, neck diameter, head diameter, and neck-shaft angle). In addition, the experimental measurements contain the failure load, which represents the mechanical strength of the femoral neck, and we calculated the correlation coefficient among BMD, geometric parameters, and failure load. RESULTS Significant correlations were discovered between femoral mechanical properties and femoral neck BMD (r=0.792, r²=0.628, P<0.001), trochanteric BMD (r=0.749, r²=0.560, P=0.001), and head diameter (r=0.706, r²=0.499, P=0.002). Multiple linear regression analyses indicated that the best predictor of hip fracture was the combination of femoral neck BMD, head diameter, and neck diameter (r²=0.844, P<0.001). CONCLUSIONS The results confirmed that, compared with BMD alone, the combination of BMD and geometric parameters of proximal femur is a better estimation of hip fracture. The geometry of the proximal femur played an important role in assessing the biomechanical strength of femur. This method greatly assists in predicting the risk of hip fracture in clinical trials and will assist studies on why the incidence of hip fracture varies among races.


Assuntos
Fêmur/anatomia & histologia , Fraturas do Quadril/etiologia , Fraturas do Quadril/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Densidade Óssea/fisiologia , Cadáver , China , Feminino , Fêmur/fisiologia , Colo do Fêmur/anatomia & histologia , Colo do Fêmur/fisiologia , Humanos , Masculino , Osteoporose Pós-Menopausa , Ossos Pélvicos , Fatores de Risco
9.
IEEE Trans Neural Netw Learn Syst ; 34(9): 6263-6275, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34982697

RESUMO

Deep clustering refers to joint representation learning and clustering using deep neural networks. Existing methods can be mainly categorized into two types: discriminative and generative methods. The former learns representations for clustering with discriminative mechanisms directly, and the latter estimate the latent distribution of each cluster for generating data points and then infers cluster assignments. Although generative methods have the advantage of estimating the latent distributions of clusters, their performances still significantly fall behind discriminative methods. In this work, we argue that this performance gap might be partly due to the overlap of data distribution of different clusters. In fact, there is little guarantee of generative methods to separate the distributions of different clusters in the data space. To tackle these problems, we theoretically prove that mutual information maximization promotes the separation of different clusters in the data space, which provides a theoretical justification for deep generative clustering with mutual information maximization. Our theoretical analysis directly leads to a model which integrates a hierarchical generative adversarial network and mutual information maximization. Moreover, we further propose three techniques and empirically show their effects to stabilize and enhance the model. The proposed approach notably outperforms other generative models for deep clustering on public benchmarks.

10.
World Neurosurg ; 170: e441-e454, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36396060

RESUMO

BACKGROUND: Tandem spinal stenosis (TSS) refers to simultaneous spinal canal stenosis of noncontiguous regions. There is no consensus in the surgical strategies for patients with symptomatic TSS because of the confusing clinical manifestations. This meta-analysis aimed to compare the outcomes of 1-stage and 2-stage decompression of all stenotic regions (cervical and lumbar/thoracic segments) in patients with TSS. METHODS: A systematic review was conducted, and a comprehensive literature search with the Japanese Orthopedic Association score, was carried out using MEDLINE, Web of Science, and PubMed databases from inception to September 13, 2022. Observational studies reporting the outcomes after 1-stage or 2-stage decompression of all symptomatic regions were included. Possible heterogeneity among studies was assessed by the Higgins I2 test, and heterogeneity was statistically investigated using the Q statistic. RESULTS: Thirteen retrospective observational studies were included in this meta-analysis. Meta-analysis showed that there was no significant difference in the Japanese Orthopedic Association score improvement in patients with TSS involving either the cervical-thoracic or cervical-lumbar segments. Regarding the surgical parameters and complications, 1-stage decompression showed comparable operation time, blood loss, and major complications to 2-stage decompression in patients with cervical and lumbar TSS. In patients with cervical and thoracic TSS, 1-stage decompression had significant advantages compared with 2-stage decompression in operation time, blood loss, and major complications. CONCLUSIONS: For patients with cervical and lumbar TSS, 2-stage decompression showed slight advantages in clinical outcome without exposing patients to unnecessary surgical risks. For patients with cervical and thoracic TSS, 1-stage decompression showed comparable clinical outcome, although with better operative parameters and lower complication rate than in simultaneous decompression.


Assuntos
Estenose Espinal , Humanos , Estenose Espinal/complicações , Constrição Patológica/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Vértebras Cervicais/cirurgia , Descompressão Cirúrgica/efeitos adversos , Vértebras Lombares/cirurgia , Estudos Observacionais como Assunto
11.
IEEE Trans Pattern Anal Mach Intell ; 45(4): 4335-4354, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35939469

RESUMO

Existing detection methods commonly use a parameterized bounding box (BBox) to model and detect (horizontal) objects and an additional rotation angle parameter is used for rotated objects. We argue that such a mechanism has fundamental limitations in building an effective regression loss for rotation detection, especially for high-precision detection with high IoU (e.g., 0.75). Instead, we propose to model the rotated objects as Gaussian distributions. A direct advantage is that our new regression loss regarding the distance between two Gaussians e.g., Kullback-Leibler Divergence (KLD), can well align the actual detection performance metric, which is not well addressed in existing methods. Moreover, the two bottlenecks i.e., boundary discontinuity and square-like problem also disappear. We also propose an efficient Gaussian metric-based label assignment strategy to further boost the performance. Interestingly, by analyzing the BBox parameters' gradients under our Gaussian-based KLD loss, we show that these parameters are dynamically updated with interpretable physical meaning, which help explain the effectiveness of our approach, especially for high-precision detection. We extend our approach from 2-D to 3-D with a tailored algorithm design to handle the heading estimation, and experimental results on twelve public datasets (2-D/3-D, aerial/text/face images) with various base detectors show its superiority.

12.
Sci Total Environ ; 892: 164423, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37236486

RESUMO

Grazing exclusion changes soil physical-chemical characteristics, rapidly affects microbial community composition and function, and alters biogeochemical processes, e.g., carbon (C) cycle, over time. However, the temporal dynamics of CO2 emission and CH4 uptake during grassland restoration chronosequences remain poorly understood. We investigated soil CO2 emission and CH4 uptake, the genes related to CO2 and CH4 production and reduction (cbbL, cbbM, chiA, and pmoA), and associated microbial communities under different durations of grazing exclusion (0, 7, 16, 25, and 38 years) to reveal the mechanisms and potential of soil CO2 emission and CH4 uptake in a semi-arid steppe. The results showed that a proper exclusion period could significantly improve soil physical-chemical conditions, vegetation community, and soil C-cycling. The abundance of C-cycling functional genes (cbbL, cbbM, chiA and pmoA), CH4 uptake and CO2 emission rates showed a single-peak pattern with increasing duration of grazing exclusion, peaking at 16 years and then decreasing in the period between 25 and 38 years, indicating that the effect of exclusion weakened when the exclusion period was too long. The changes in C-cycling functional genes and microbial communities are primarily influenced by aboveground net primary productivity (ANPP), and are associated with CO2, CH4, soil water content (SWC), and soil organic carbon (SOC). Structural equation modeling showed that increases in SOC content and pmoA abundance caused by an increase in ANPP accelerated CO2 emission and CH4 uptake rates, respectively. Our results provide valuable insights into the critical role of grazing exclusion in promoting grassland restoration and carbon sequestration, and have potential implications for sustainable land management practices.


Assuntos
Sequestro de Carbono , Solo , Solo/química , Carbono , Dióxido de Carbono , Ciclo do Carbono , Pradaria
13.
Int J Biol Macromol ; 231: 123284, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36657538

RESUMO

Borate crosslinked guar gum gels have played a vital role in stimulating oil and gas wells for many years; however, the high dosage of guar gum in the existing fracturing fluid will increase the cost and cause more damage to the reservoir and ultimately affect the effect of stimulation. In this study, borate esters are modified onto polyethyleneimine (PEI) of different molecular weights, affording organic borate crosslinkers of different sizes. By analyzing the effect of crosslinker size on gel rheology, sand-carrying properties, and microstructure, it is observed that the crosslinking efficiency is most significantly enhanced when the crosslinker size is similar to the diameter of the guar gum molecules. This makes it possible for the gel to maintain good performance at low polymer concentrations and meet the performance requirements of fracturing, which provides new ideas for developing the next generation of economical, clean, and green fracturing fluids.


Assuntos
Boratos , Galactanos , Boratos/química , Galactanos/química , Mananas/química , Gomas Vegetais/química , Géis , Reologia
14.
Spine (Phila Pa 1976) ; 47(24): 1746-1752, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35917289

RESUMO

STUDY DESIGN: A cross-sectional study. OBJECTIVE: To quantify the severity of neurogenic intermittent claudication (NIC) for patients with lumbar spinal stenosis (LSS) based on the center of pressure trajectory. SUMMARY OF BACKGROUND DATA: NIC is one of the typical symptoms of LSS. So far, the severity level of NIC is mainly evaluated by the subjective description of patients, which might be biased by patients' background differences and thus lead to an ineffective diagnosis or inappropriate treatment for LSS. Therefore, it remains necessary to develop a reliable clinical technique for quantitative evaluation of NIC to achieve more effective therapy for LSS. MATERIALS AND METHODS: In the present study, the Footscan pressure system was used to detect the center of pressure trajectory. The real-time walking distance (rtWD) and the corresponding displacement of the medial-lateral center of pressure (ML-COP) were calculated based on the trajectory. The differences of ML-COP between LSS and control groups were analyzed using a one-way repeated measures analysis of variance. Regression and Pearson correlation analysis were used to investigate the correlation between rtWD and ML-COP, as well as the relation between the Oxford Claudication Score (OCS) and clinical evaluation indicators. RESULTS: The present study included 31 LSS patients and 31 healthy controls. There were no significant differences in demographic data between the two groups ( P >0.05). The results indicated that ML-COP would increase with the number of laps in the LSS group while not in the control group. Also, a linear relationship was identified between the ML-COP and rtWD for LSS patients ( R2 >0.80, P <0.05). Since the incremental rate of ML-COP for LSS patients was reflected by the regression coefficients of the linear regression analysis, thus the regression coefficients were defined as the claudication correlation coefficients (CCCs). In addition, it was indicated by the statistical analysis that there was a strong positive correlation between OCS and CCC ( r =0.96; P <0.001) and a medium negative correlation with final walking distance ( r =-0.67; P <0.001). It was also noticed that there was no significant correlation between the average ML-COP and OCS ( r =-0.03; P =0.864). CONCLUSIONS: The ML-COP of LSS patients would increase with the patients' walking distance. This incremental rate, characterized by the CCC, would be used as an effective indicator to quantify the severity level of the NIC for potentially more accurate and reliable diagnosis, evaluation, and treatment of LSS. LEVEL OF EVIDENCE: 3.


Assuntos
Estenose Espinal , Humanos , Estenose Espinal/complicações , Estenose Espinal/diagnóstico , Estenose Espinal/terapia , Claudicação Intermitente/diagnóstico , Estudos Transversais , Marcha , Perna (Membro) , Vértebras Lombares
15.
Br J Sports Med ; 45(4): 270-4, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21047841

RESUMO

OBJECTIVE: How to organise an appropriate team to provide quality dental care during the Olympic Games has become an important consideration for each successive host country. The aims of this study were to document dental services provided at the Olympic Games and to provide data for planning future events. SET-UP OF THE DENTAL CARE DEPARTMENT: There were six dental chairs in six independent treatment rooms, one technical laboratory, a sterilising room and an x-ray room equipped with one digital panoramic screening machine and one intraoral x-ray machine in the polyclinic in the Olympic Village in Beijing. Shifts comprised 80 dentists and 28 nurses who were organised into three shifts working from 08:00 until 23:00. RESULTS: In the 2008 Olympic Games, there were 1607 cases involving 1126 patients requiring dental care: 795 cases from 516 athletes; 483 cases from 370 coaches and other staff; and 99 cases from volunteers. Endodontic treatments, permanent fillings, oral hygiene, mouthguards and treatment of pericoronitis were the most frequent procedures in dental care. The Mouthguard Service was extremely popular and well utilised. 122 athletes received new custom-made mouthguards in Beijing. CONCLUSIONS: As the utilisation of the dental service grows, and the burden of providing care for such a large cohort increases, a well-organised dental team becomes increasingly important. More general-practice dentists were needed in the team. Different kinds of specialist were suggested for working in the team-for example, oral and maxillofacial surgeons, sport dentists for mouthguards and endodontists.


Assuntos
Assistência Odontológica/organização & administração , Esportes/estatística & dados numéricos , China , Assistência Odontológica/estatística & dados numéricos , Restauração Dentária Permanente/estatística & dados numéricos , Humanos , Protetores Bucais/estatística & dados numéricos , Visita a Consultório Médico/estatística & dados numéricos , Higiene Bucal/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Tratamento do Canal Radicular/estatística & dados numéricos , Fatores de Tempo
16.
J Digit Imaging ; 24(1): 86-95, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19937083

RESUMO

Intracranial aneurysms represent a significant cause of morbidity and mortality. While the risk factors for aneurysm formation are known, the detection of aneurysms remains challenging. Magnetic resonance angiography (MRA) has recently emerged as a useful non-invasive method for aneurysm detection. However, even for experienced neuroradiologists, the sensitivity to small (<5 mm) aneurysms in MRA images is poor, on the order of 30~60% in recent, large series. We describe a fully automated computer-aided detection (CAD) scheme for detecting aneurysms on 3D time-of-flight (TOF) MRA images. The scheme locates points of interest (POIs) on individual MRA datasets by combining two complementary techniques. The first technique segments the intracranial arteries automatically and finds POIs from the segmented vessels. The second technique identifies POIs directly from the raw, unsegmented image dataset. This latter technique is useful in cases of incomplete segmentation. Following a series of feature calculations, a small fraction of POIs are retained as candidate aneurysms from the collected POIs according to predetermined rules. The CAD scheme was evaluated on 287 datasets containing 147 aneurysms that were verified with digital subtraction angiography, the accepted standard of reference for aneurysm detection. For two different operating points, the CAD scheme achieved a sensitivity of 80% (71% for aneurysms less than 5 mm) with three mean false positives per case, and 95% (91% for aneurysms less than 5 mm) with nine mean false positives per case. In conclusion, the CAD scheme showed good accuracy and may have application in improving the sensitivity of aneurysm detection on MR images.


Assuntos
Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico , Angiografia por Ressonância Magnética , Angiografia Digital , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Sensibilidade e Especificidade
17.
Polymers (Basel) ; 13(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34503012

RESUMO

A quaternary polymer (HGP) was prepared by the free-radical polymerization of acrylamide, acrylic acid, maleic anhydride functionalized ß-cyclodextrin (MAH-ß-CD), and N-(3-methacrylamidopropyl)-N, N-dimethylnaphthalen-1-aminium chloride (NAP). It was found that host-guest behavior occurred most effectively at a molar rate of NAP and CD with 1:1, which exhibited better solubility than hydrophobically associative polymer. Moreover, the as-prepared polymer has superior salt tolerance, shear resistance, and viscoelasticity due to host-guest strategy. More importantly, the HGP solution simulates the distribution of formation water in the Bohai SZ1-1 oilfield has good rheological properties at 120 °C. All results show that the proposed polymer could be a competitive candidate in oilfield applications such as fracturing fluids, displacement fluids, and drilling fluids.

18.
Top Curr Chem (Cham) ; 379(2): 13, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33624162

RESUMO

The burgeoning interest in synthesis and biological applications of 1,6-naphthyridines reflects the importance of 1,6-naphthyridines in the synthetic as well as medicinal chemistry fields. Specially, 1,6-naphthyridines are pharmacologically active, with variety of applications such as anticancer, anti-human immunodeficiency virus (HIV), anti-microbial, analgesic, anti-inflammatory and anti-oxidant activities. Although collective recent synthetic developments have paved a path to a wide range of functionalized 1,6-naphthyridines, a complete correlation of synthesis with biological activity remains elusive. The current review focuses on recent synthetic developments from the last decade and a thorough study of the anticancer activity of 1,6-naphthyridines on different cancer cell lines. Anticancer activity has been correlated to 1,6-naphthyridines using the literature on the structure-activity relationship (SAR) along with molecular modeling studies. Exceptionally, at the end of this review, the utility of 1,6-naphthyridines displaying activities other than anticancer has also been included as a glimmering extension.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Naftiridinas/síntese química , Naftiridinas/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Naftiridinas/química , Relação Estrutura-Atividade
19.
Biomed Res Int ; 2020: 5043583, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685495

RESUMO

Lumbar spinal stenosis (LSS) is a common disease in the elderly population; it has been reported that patients with LSS have an abnormal gait pattern due to symptom such as neurogenic intermittent claudication (NIC); however, no detailed reports exist on the plantar pressure distributions in LSS patients with NIC. To analysis the plantar pressure characteristics of LSS patients, the Footscan® pressure system was used to perform dynamic plantar pressure measurements in 20 LSS patients (age, 69.5 ± 7.2 years) before and after the occurrence of NIC. The contact time (CT), foot progression angle (FPA), pressure-time integral (PTI), and contact area (CA) were collected and compared between the LSS patients and age-matched healthy subjects in each measurement. The LSS group showed an increase in forefoot CT%, PTI, and CA% in both measurements compared with those in the control group. After the occurrence of NIC in the LSS group, CT%, PTI, and CA% of the forefoot increased further compared with those before the occurrence of NIC. In addition, after the occurrence of NIC, the PTI and CA% of the forefoot shifted from the medial foot to the lateral foot. The results suggested that the plantar pressure distributions of patients with LSS differs from normal subjects due to the posture of waking with lumbar forward flexion, and the forefoot bears a higher relative load. In addition, the occurrence of NIC could affect the plantar pressure distribution of the patients with LSS, predicting the patient's risk of falling to the anterior direction and to the symptomatic side.


Assuntos
Marcha , Claudicação Intermitente/fisiopatologia , Vértebras Lombares/fisiopatologia , Pressão , Estenose Espinal/fisiopatologia , Idoso , Estudos Transversais , Feminino , Pé/fisiopatologia , Humanos , Claudicação Intermitente/patologia , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Estenose Espinal/patologia
20.
Polymers (Basel) ; 12(4)2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32325993

RESUMO

Three kinds of drag reducer were synthesized by inverse emulsion polymerization and named PHWAM-1, PHWAM-2, and PHWAM-3. Drag reduction (DR) tests showed that the three drag reducers have different DR characteristics in fresh water and various saline waters because of their different types of hydrophobic monomers. PHWAM-1, without hydrophobic monomers, performs better in fresh water, while PHWAM-2 and PHWAM-3, with hydrophobic monomers, perform better in brine. In addition, PHWAM-3, which has twin-tailed hydrophobic monomers, performs best in high-concentration brine. Measurements of micro-particle size and observations of spatial structure suggest that although the stronger hydrophobic polymer has no DR advantage over a linear polymer in fresh water, the molecular chains form a mutually associative supporting structure that improves the DR performance over that of a linear polymer in high-concentration brine.

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