RESUMO
BACKGROUND: For patients with rotator cuff tear (RCT), the contra-lateral shoulders have higher risk of RCT than general population. It has been proved by several previous studies. The focus of this study is to obtain the data of contra-lateral rotator cuff tear in Chinese population, and to find the rules of contra-lateral rotator cuff tear through statistical analysis. METHODS: From March 2016 to January 2020, patients who underwent shoulder arthroscopic surgery were included in the study, we conduct bilateral shoulder ultrasound before surgery, patients information collection include gender, age, occupation and whether received contra-lateral rotator cuff surgery within 1-3 years. The above information was statistically analyzed. RESULTS: According to the inclusion and exclusion criteria, 401 patients were included. The incidence of contra-lateral rotator cuff tear was 24.3%, 5.58% of them underwent contra-lateral rotator cuff repair surgery within 3 years. The degree of contra-lateral rotator cuff tear was positively correlated with the degree of the primary side; Patients with full-thickness rotator cuff tear were more likely to have contra-lateral rotator cuff tear than patients with partial rotator cuff tear. For patients with supraspinatus tendon tear, the contra-lateral rotator cuff tear risk increases, For patients with subscapularis muscle tear, the contra-lateral rotator cuff tear risk doesn't increases. Contra-lateral rotator cuff tear is related to age, the risk of contra-lateral rotator cuff tear is higher in elderly patients. CONCLUSIONS: The contra-lateral RCT data obtained in our study was 24.3%, significantly lower than that of previous studies. The reasons may include ethnic variation, lifestyle, and proportion of heavy physical labor. The condition of contra-lateral rotator cuff is closely related to affected side rotator cuff tear.
RESUMO
Objective To explore the optimal administration route of tranexamic acid (TXA) in shoulder arthroscopic surgery. Methods Patients undergoing arthroscopic rotator cuff repair were randomly divided into four groups: control group (without TXA treatment), intravenous group (TXA was intravenously administered 10 minutes before surgery), irrigation group (TXA was added to the irrigation fluid during subacromial decompression and acromioplasty), and intravenous plus irrigation group (TXA was applied both intravenously and via intra-articular irrigation). The primary outcome was visual clarity assessed with visual analog scale (VAS) score, and the secondary outcomes included irrigation fluid consumption and time to subacromial decompression and acromioplasty procedure. Results There were 134 patients enrolled in the study, including 33 in the control group, 35 in the intravenous group, 32 in the irrigation group, and 34 in the intravenous plus irrigation group. The median and interquartile range of VAS scores for the intravenous, irrigation, and intravenous plus irrigation groups were 2.70 (2.50, 2.86) (Z = -3.677, P = 0.002), 2.67 (2.50, 2.77) (Z = -3.058, P < 0.001), and 2.91 (2.75, 3.00) (Z = -6.634, P < 0.001), respectively, significantly higher than that of the control group [2.44 (2.37, 2.53)]. Moreover, the control group consumed more irrigation fluid than the intravenous group, irrigation group, and intravenous plus irrigation group (all P < 0.05). The intravenous plus irrigation group consumed less irrigation fluid than either the intravenous group or the irrigation group (both P < 0.001). There was no difference in subacromial decompression and acromioplasty operative time among the four groups. Conclusion TXA applied both topically and systematically can improve intraoperative visual clarity, and the combined application is more effective.
Assuntos
Ácido Tranexâmico , Humanos , Ácido Tranexâmico/uso terapêutico , Ombro , Artroscopia/métodos , Descompressão Cirúrgica/métodos , Resultado do TratamentoRESUMO
Though chiral pool synthesis is widely accepted as a powerful strategy in complex molecule synthesis, the effectiveness of the approach is intimately linked to the range of available chiral building blocks and the functional groups they possess. To date, there is still a pressing need for new remote functionalization methods that would allow the installation of useful chemical handles on these building blocks to enable a broader spectrum of synthetic manipulations. Herein, we report the engineering of a P450BM3 variant for the regioselective C-H oxidation of sclareol at C6. The synthetic utility of the resulting product was demonstrated in a formal synthesis of ansellone B, the first total synthesis of the 2,3-seco-labdane excolide B, and a model study toward (+)-pallavicinin.
Assuntos
Diterpenos , Terpenos , OxirreduçãoRESUMO
OBJECTIVE: To explore the value of virtual touch imaging and quantification (VTIQ) shear wave elastography (SWE) in diagnosis of supraspinatus tendon tear. METHODS: Eighty patients with unilateral supraspinatus tendon tear underwent shoulder arthroscopy were prospective studied. Tendinopathy, partial-thickness tear or full-thickness tear of supraspinatus tendon were diagnosed according 2D ultrasound examination. Sensitivity, specificity and accuracy of ultrasonic diagnosis of supraspinatus tendon tear were calculated by arthroscopy as the gold standard. VTIQ was applied to measure the shear-wave velocity (SWV) of both normal and affected supraspinatus tendon. The differences of SWV in three types of supraspinatus tendon tear and receiver operating characteristic (ROC) curves were analyzed. RESULTS: Among 80 patients, there were 20 tendinopathy, 31 partial tears and 29 full-thickness tears diagnosed by shoulder arthroscopy. Sensitivity, specificity and accuracy of 2D ultrasound in diagnosis of tendinopathy, partial tear and full-thickness tear groups were 78%, 90%and 83%; 71%, 86%and 73%; 86%, 88%and 88%, respectively. SWV of 80 supraspinatus tendon tears was 4.59±1.00âm/s, which was lower than that of normal supraspinatus tendon (4.59±1.00âm/s vs. 6.68±1.05âm/s, Pâ<â0.01). SWV of supraspinatus tendon in tendinopathy, partial tear and full-thickness tear groups respectively were 5.66±0.97, 4.66±1.00, and 3.78±0.55âm/s, all lower than that of the contralateral normal supraspinatus tendon (all Pâ<â0.05). In addition, the analysis of variance and pairwise comparison showed that SWV of supraspinatus tendon among three different degree of injury was statistically significant (all Pâ<â0.001). The cutoff thresholds of SWV was 4.83âm/s to identify tendinopathy tear from partial tear and was 4.08âm/s to identify full-thickness tear from partial-thickness tear. CONCLUSION: VTIQ SWE with SWV might identify degree of supraspinatus tendon tear and improve the value of ultrasonography, which should be further evaluated in large multicenter studies.
Assuntos
Técnicas de Imagem por Elasticidade , Lesões do Manguito Rotador , Traumatismos dos Tendões , Humanos , Estudos Prospectivos , Manguito Rotador/diagnóstico por imagem , Lesões do Manguito Rotador/diagnóstico por imagem , Lesões do Manguito Rotador/cirurgia , Traumatismos dos Tendões/diagnóstico por imagem , Ultrassonografia/métodosRESUMO
OBJECTIVE: To investigate and evaluate the accuracy of ultrasound (US) imaging for measurement of ischiofemoral space (IFS) compared with magnetic resonance imaging (MRI). METHODS: Twenty-five hips of 16 patients with hip pain and ipsilateral quadratus femoris muscle (QFM) edema were recruited to the IFI group, and 19 hips of 19 patients without hip pain and QFM edema were recruited as the control group. IFS of both groups was measured by US and MRI. The correlations and differences between US and MRI measurements were then assessed. Last, the receiver operating characteristic (ROC) data analysis was performed. RESULTS: The US results revealed a decreased IFS in IFI hips compared with controls (Pâ<â0.001), suggesting that US were valuable in identifying IFI. IFS measured by US and MRI showed positive correlations in both the IFI group (râ=â0.409, Pâ=â0.042) and control group (râ=â0.575, Pâ=â0.01). There were no statistically significant differences between IFS measured by US and MRI in the control group (Pâ=â0.657), while IFS measurements in the IFI group performed with US were significantly greater than those with MRI (Pâ<â0.001). ROC curve analysis revealed that the cutoff value of IFS measured with US was 2.14âcm, with a sensitivity of 92.0% and specificity of 68.4%, while measured by MRI was 1.87âcm, with a sensitivity of 96.0% and specificity of 84.2%. CONCLUSIONS: IFS measurements obtained with US are very similar to those obtained with MRI. Therefore, US provides a low-cost and easy-to-operate alternative imaging modality to measure IFS.
Assuntos
Fêmur/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Ísquio/diagnóstico por imagem , Adulto , Artralgia/diagnóstico por imagem , Artralgia/patologia , Edema/diagnóstico por imagem , Edema/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Quadríceps/diagnóstico por imagem , Sensibilidade e Especificidade , UltrassonografiaRESUMO
We report on our accomplishment of the asymmetric synthesis of hispidaninâ A and its natural precursor, a labdane diterpenoid. In the first generation of synthesis, a semi-synthesis strategy was employed to construct a labdane-type diterpenoid, a natural precursor of hispidaninâ A, in which Barton's photolytic remote functionalization was employed as a key transformation. In addition, the totarane-type dienophile counterpart was derived from commercially available (-)-scalareol. In the second generation of synthesis, key elements included an iron-catalyzed radical cascade to access the labdane-type diene on the basis of hydrogen atom transfer, and an enantioselective cationic polyene cyclization furnished the totarane-type dienophile. Reaction optimization and mechanistic analysis of the radical cascade reaction was conducted. Furthermore, the [4+2] cycloaddition reaction was achieved in excellent yield and selectivity under thermal conditions, which has been rationalized by using DFT transition-state analysis and paved the way for final accomplishment of the total synthesis of hispidaninâ A.
RESUMO
The syntheses of members of a family of lindenane sesquiterpenoid [4+2] dimers led to the total syntheses of sarcandrolideâ J and shizukaolâ D. Inspired by a modified biosynthetic pathway, a cascade featuring furan formation/alkene isomerization/Diels-Alder cycloaddition was devised to construct the congested polycyclic architecture of the target molecules with the correct stereochemistry. This study presents a pioneering synthetic entry to this family of natural products and paves the way for fully exploring their biological functions.
Assuntos
Dimerização , Sesquiterpenos/síntese química , Triterpenos/síntese química , Reação de Cicloadição , Conformação Molecular , Sesquiterpenos/química , Estereoisomerismo , Triterpenos/químicaRESUMO
Asymmetric total synthesis of the dimeric diterpenoid hispidaninâ A was accomplished by non-catalytic Diels-Alder cycloaddition at room temperature. The synthesis relies on iron-catalyzed coupling to construct a Z-configured trisubstituted alkene, an iron-catalyzed radical cascade to generate a labdane-type diene, and both Yamamoto cationic polyene cyclization and palladium-catalyzed Stille coupling to generate a totarane-type dienophile.
Assuntos
Alcenos/química , Diterpenos/síntese química , Ferro/química , Paládio/química , Catálise , Ciclização , Diterpenos/química , Estrutura MolecularRESUMO
The first synthesis of a labdane-type diterpenoid isolated from Isodon yuennanensis was achieved in fourteen steps from commercially available starting material, (+)-sclareolide. The synthesis features the Barton nitrite ester reaction to introduce an oxime at the angular methyl group and the Jones oxidation to construct the lactone segment. By comparison of the optical rotation of our synthetic sample and the natural sample, the absolute stereochemistry of the natural diterpenoid has been determined.
Assuntos
Diterpenos/química , Diterpenos/síntese química , Metacrilatos/química , Nitratos/química , Rizoma/química , Fluoreto de Sódio/química , Diterpenos/isolamento & purificação , Conformação Molecular , EstereoisomerismoRESUMO
Illicium verum was a medicinal plant containing many valuable active ingredients. However, the rich extracts from its fruit are invariably wasted for inefficient separation processes. To further utilize these resources, the four extracts were obtained. The results showed that the optimum extraction times for methanol/ethanol, ether/ethanol, benzene/ethanol, and petroleum ether/ethanol extraction were 3, 5, 9, and 5 h for each single extraction, respectively. Among the four methods, the third method was found to be optimum, and gave a maximum yield of 31.63%. It was suggested that the extracts could be used as rare spices, biomedicines, liquid bioenergy, etc.
Assuntos
Illicium/química , Extratos Vegetais/análise , FrutasRESUMO
Objective: To explore the value of dual-accelerated simultaneous multi-slice (SMS) imaging in diffusion tensor imaging (DTI) of glioma. Methods: Thirty-four patients with glioma who underwent magnetic resonance imaging (MRI) in our hospital from January 2022 to March 2023 were randomly selected. The results of dual-accelerated SMS-DTI and conventional DTI were retrospectively analyzed. All patients were scanned using a uMR790 3.0T MRI scanner, and the scanning technicians followed a predefined sequence to ensure consistency in scan parameters. The images were subjectively evaluated using a Likert 5-point scoring system. Objective evaluation was performed by measuring the required values of the images with b-value = 1000 s/mm2, primarily measuring the signal intensity in the tumor region and the contralateral normal brain white matter region. The standard deviation values were used to calculate the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the same encoding direction as the background noise. The number of generated fiber pathways, fractional anisotropy (FA), and mean diffusivity (MD) were measured and analyzed using post-processing software. The relative FA (rFA) and relative MD (rMD) were calculated. Results: The results of conventional DTI and SMS-accelerated DTI were compared. In terms of subjective evaluation, including overall image quality, tumor edge clarity, and magnetic sensitivity artifacts, both techniques showed no significant differences, indicating comparable diagnostic performance in anatomical visualization. In terms of objective evaluation and quantitative parameter measurement, there were statistically significant differences in SNR and CNR values, with slightly lower values in the dual-accelerated SMS-DTI compared with conventional DTI, a significant reduction in scanning time can be achieved through a slight loss in image quality. The number of fiber pathways and the rFA and rMD values did not show typical differences between the two techniques. The correlation between these measures was highly similar, with no significant differences observed. Conclusion: The application of dual-accelerated simultaneous multi-slice imaging in DTI of glioma is feasible.
RESUMO
Nimbolide, a ring seco-C limonoid natural product, was recently found to inhibit the poly(ADP)-ribosylation (PARylation)-dependent ubiquitin E3 ligase RNF114. In doing so, it induces the 'supertrapping' of both PARylated PARP1 and PAR-dependent DNA-repair factors. PARP1 inhibitors have reshaped the treatment of cancer patients with germline BRCA1/2 mutations partly through the PARP1 trapping mechanism. To this end, modular access to nimbolide analogues represents an opportunity to develop cancer therapeutics with enhanced PARP1 trapping capability. Here we report a convergent synthesis of nimbolide through a late-stage coupling strategy. Through a sulfonyl hydrazone-mediated etherification and a radical cyclization, this strategy uses a pharmacophore-containing building block and diversifiable hydrazone units to enable the modular synthesis of nimbolide and its analogues. The broad generality of our synthetic strategy allowed access to a variety of analogues with their preliminary cellular cytotoxicity and PARP1 trapping activity reported.
RESUMO
Ni-based superalloys are widely used in aerospace applications. However, traditional constitutive equations often lack the necessary accuracy to predict their high-temperature behavior. A novel constitutive model, utilizing Taylor series expansions and partial derivatives, is proposed to predict the high-temperature flow behavior of a nickel-based superalloy. Hot compression tests were conducted at various strain rates (0.01 s-1, 0.1 s-1, 1 s-1, and 10 s-1) and temperatures (850 °C to 1200 °C) to gather comprehensive experimental data. The performance of the new model was evaluated against classical models, specifically the Arrhenius and Hensel-Spittel (HS) models, using metrics such as the correlation coefficient (R), root mean square error (RMSE), sum of squared errors (SSE), and sum of absolute errors (SAE). The key findings reveal that the new model achieves superior prediction accuracy with an R value of 0.9948 and significantly lower RMSE (22.5), SSE (16,356), and SAE (5561 MPa) compared to the Arrhenius and HS models. Additionally, the stability of the first-order partial derivative of logarithmic stress with respect to temperature (∂lnσ/∂T) indicates that the logarithmic stress-temperature relationship can be approximated by a linear function with minimal curvature, which is effectively described by a second-degree polynomial. Furthermore, the relationship between logarithmic stress and logarithmic strain rate (∂lnσ/∂lnεË) is more precisely captured using a third-degree polynomial. The accuracy of the new model provides an analytical basis for finite element simulation software. This helps better control and optimize processes, thus improving manufacturing efficiency and product quality. This study enables the optimization of high-temperature forming processes for current superalloy products, especially in aerospace engineering and materials science. It also provides a reference for future research on constitutive models and high-temperature material behavior in various industrial applications.
RESUMO
BACKGROUND: More than 40% of patients with resectable esophageal squamous cell cancer (ESCC) achieve pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT), who have favorable prognosis and may benefit from an organ-preservation strategy. Our study aims to develop and validate a machine learning model based on MR radiomics to accurately predict the pCR of ESCC patients after nCRT. METHODS: In this retrospective multicenter study, eligible patients with ESCC who underwent baseline MR (T2-weighted imaging) and nCRT plus surgery were enrolled between September 2014 and September 2022 at institution 1 (training set) and between December 2017 and August 2021 at institution 2 (testing set). Models were constructed using machine learning algorithms based on clinical factors and MR radiomics to predict pCR after nCRT. The area under the curve (AUC) and cutoff analysis were used to evaluate model performance. RESULTS: A total of 155 patients were enrolled in this study, 82 in the training set and 73 in the testing set. The radiomics model was constructed based on two radiomics features, achieving AUCs of 0.968 (95%CI 0.933-0.992) in the training set and 0.885 (95%CI 0.800-0.958) in the testing set. The cutoff analysis resulted in an accuracy of 82.2% (95%CI 72.6-90.4%), a sensitivity of 75.0% (95%CI 58.3-91.7%), and a specificity of 85.7% (95%CI 75.5-96.0%) in the testing set. CONCLUSION: A machine learning model based on MR radiomics was developed and validated to accurately predict pCR after nCRT in patients with ESCC.
Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Terapia Neoadjuvante , Radiômica , AlgoritmosRESUMO
Hot tensile tests of the GH3625 superalloy were carried out under the temperature range of 800-1050 °C and strain rates of 0.001, 0.01, 0.1, 1, and 10 s-1 on a Gleeble-3500 metallurgical processes simulator. The effect of temperature and holding time on grain growth was investigated to determine the proper heating schedule of the GH3625 sheet in hot stamping. The flow behavior of the GH3625 superalloy sheet was analyzed in detail. The work hardening model (WHM) and the modified Arrhenius model, considering the deviation degree R (R-MAM), were constructed to predict the stress of flow curves. The results showed that WHM and R-MAM have good prediction accuracy by evaluating the correlation coefficient (R) and the average absolute relative error (AARE). Additionally, the plasticity of the GH3625 sheet at elevated temperature drops with the increasing temperature and decreasing strain rate. The best deformation condition of the GH3625 sheet in the hot stamping is in the range of 800~850 °C and 0.1~10 s-1. Finally, a hot stamped part of the GH3625 superalloy was produced successfully, which had higher tensile strength and yield strength than the as-received sheet.
RESUMO
Numerical simulations and experiments were utilized to study the removal of oxide scale formed on 300 M steel special-shaped hot forging surfaces during heating at elevated temperature by a high-pressure water descaling process. Specifically, the experimental setup of the special-shaped hot forging was designed and manufactured according to the descaling parameters and simulation results obtained from the hot rolling process. The force states of three typical hot forging surfaces impinged by high-pressure water jets were analyzed. Moreover, the mechanism of the high-pressure water descaling process was proposed based on the research results. The numerical simulations and experimental results revealed that the velocity distribution of the high-pressure water jets is relatively different in various areas of the special-shaped hot forging surfaces. Therefore, the descaling performance is synergistically influenced by the velocity of the high-pressure water jet and the shape of the special-shaped hot forging. Given a certain spray pressure, the value of impact force Fi plays a significant role in the descaling of the typical hot forging. The larger the value of Fi on the typical hot forging surface, the easier it is to remove the oxide scale, and vice versa. Accordingly, the difficulty of removing the oxide scale formed on the 300 M steel special-shaped hot forging surfaces during heating at elevated temperature by a high-pressure water descaling process is in the following order: plane surface < convex surface < concave surface. Additionally, only the inner-layer FeO of the oxide scale remained after the high-pressure water descaling process due to the appearance of FeO-Fe2SiO4 eutectic in the FeO layer.
RESUMO
Purpose: We compare the efficacy and safety of regorafenib plus immune checkpoint inhibitors (ICIs) with transarterial chemoembolization (R+ICIs+TACE) versus regorafenib plus ICIs (R+ICIs) as the second-line treatment for patients with advanced hepatocellular carcinoma (HCC). Methods: This retrospective study included patients with advanced HCC who received R+ICIs+TACE or R+ICIs as the second-line treatment from January 2019 to April 2022. Objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and treatment-related adverse events (TRAEs) were compared between the two groups. The propensity score matching (PSM) was used to reduce the influence of confounding factors on the outcomes. Factors affecting PFS and OS were analyzed using a Cox proportional-hazards regression model. Results: In total, 52 patients were included in this study, of whom 28 patients received R+ICIs+TACE and 24 patients received R+ICIs. After PSM (n=23 in each group), patients who received R+ICIs+TACE had a higher ORR (34.8% vs 4.3%, P=0.009), a longer PFS (5.8 vs 2.6 months, P<0.0001), and a longer OS (15.0 vs 7.5 months, P=0.014) than those who received R+ICIs. Age ≤ 50 years old, Child-Pugh class A6 and B7, and R+ICIs were found as independent prognostic factors for poor PFS. R+ICIs, α-fetoprotein >400 ng/mL, and platelet-to-lymphocyte ratio >133 were noted as independent prognostic factors for poor OS. The difference in the incidence of TRAEs between the two groups was not statistically significant (P> 0.05). Conclusion: Compared to regorafenib plus ICIs, regorafenib plus ICIs with TACE was tolerated and improved survival as the second-line treatment for patients with advanced HCC.
RESUMO
TC31 is a new type of high-temperature titanium alloy, but few researchers have studied the combination of forming and heat treatment of a component using this material. The component with high ribs and thin webs was studied by numerical simulation and trail production. Based on the establishment of the finite element model, the forming process was analyzed by simulation software, and the maximum forming load of the component was 1920 kN. Ultimately, there were no folding defects of the component during the forming process. The material flow law was revealed by selecting the typical section of the component, and then the forming process was verified and the fully filled component was obtained. After that, the component was subjected to post-processing, and three heat treatment methods were designed to conduct heat treatment experiments on it (heat treatment: solution treatment and aging treatment). By analyzing the influence of three heat treatment methods on mechanical properties, the optimal heat treatment method was obtained, namely a solution treatment at 960 °C for 2.5 h and aging treatment at 610 °C for 7 h. The ultimate tensile strength, yield strength, elongation, and section shrinkage of the component through forging forming and heat treatment are higher than those of original material; meanwhile, it also indicates that the designed heat treatment has a better effect on the high-temperature mechanical properties of this titanium alloy at 650 °C than that at 450 °C. The research on the combination of the forming and heat treatment of this component provides a reference for the engineering application of high-temperature titanium alloys.
RESUMO
Recent studies have pointed to PARP1 trapping as a key determinant of the anticancer effects of PARP1 inhibitors (PARPi). We identified RNF114, as a PARylation-dependent, E3 ubiquitin ligase involved in DNA damage response. Upon sensing genotoxicity, RNF114 was recruited, in a PAR-dependent manner, to DNA lesions, where it targeted PARP1 for degradation. The blockade of this pathway interfered with the removal of PARP1 from DNA lesions, leading to profound PARP1 trapping. We showed that a natural product, nimbolide, inhibited the E3 ligase activity of RNF114 and thus caused PARP1 trapping. However, unlike conventional PARPi, nimbolide treatment induced the trapping of both PARP1 and PARylation-dependent DNA repair factors. Nimbolide showed synthetic lethality with BRCA mutations, and it overcame intrinsic and acquired resistance to PARPi, both in vitro and in vivo. These results point to the exciting possibility of targeting the RNF114-PARP1 pathway for the treatment of homologous recombination-deficient cancers.