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Proliferating cells known as neoblasts include pluripotent stem cells (PSCs) that sustain tissue homeostasis and regeneration of lost body parts in planarians. However, the lack of markers to prospectively identify and isolate these adult PSCs has significantly hampered their characterization. We used single-cell RNA sequencing (scRNA-seq) and single-cell transplantation to address this long-standing issue. Large-scale scRNA-seq of sorted neoblasts unveiled a novel subtype of neoblast (Nb2) characterized by high levels of PIWI-1 mRNA and protein and marked by a conserved cell-surface protein-coding gene, tetraspanin 1 (tspan-1). tspan-1-positive cells survived sub-lethal irradiation, underwent clonal expansion to repopulate whole animals, and when purified with an anti-TSPAN-1 antibody, rescued the viability of lethally irradiated animals after single-cell transplantation. The first prospective isolation of an adult PSC bridges a conceptual dichotomy between functionally and molecularly defined neoblasts, shedding light on mechanisms governing in vivo pluripotency and a source of regeneration in animals. VIDEO ABSTRACT.
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Proteínas Argonautas/metabolismo , Proteínas de Helminto/metabolismo , Planárias/fisiologia , Tetraspaninas/metabolismo , Animais , Proteínas Argonautas/antagonistas & inibidores , Proteínas Argonautas/genética , Ciclo Celular/efeitos da radiação , Regulação da Expressão Gênica , Proteínas de Helminto/antagonistas & inibidores , Proteínas de Helminto/genética , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/transplante , Análise de Componente Principal , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , RNA de Helmintos/química , RNA de Helmintos/isolamento & purificação , RNA de Helmintos/metabolismo , Regeneração/genética , Análise de Sequência de RNA , Análise de Célula Única , Tetraspaninas/genética , Irradiação Corporal TotalRESUMO
Degradation and collapse of stalled replication forks are main sources of genomic instability, yet the molecular mechanisms for protecting forks from degradation/collapse are not well understood. Here, we report that human CST (CTC1-STN1-TEN1) proteins, which form a single-stranded DNA-binding complex, localize at stalled forks and protect stalled forks from degradation by the MRE11 nuclease. CST deficiency increases MRE11 binding to stalled forks, leading to nascent-strand degradation at reversed forks and ssDNA accumulation. In addition, purified CST complex binds to 5' DNA overhangs and directly blocks MRE11 degradation in vitro, and the DNA-binding ability of CST is required for blocking MRE11-mediated nascent-strand degradation. Our results suggest that CST inhibits MRE11 binding to reversed forks, thus antagonizing excessive nascent-strand degradation. Finally, we uncover that CST complex inactivation exacerbates genome instability in BRCA2 deficient cells. Collectively, our findings identify the CST complex as an important fork protector that preserves genome integrity under replication perturbation.
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Replicação do DNA/genética , Proteína Homóloga a MRE11/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla , DNA Helicases/metabolismo , Reparo do DNA/genética , DNA de Cadeia Simples/genética , Proteínas de Ligação a DNA/metabolismo , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Ligação Proteica/genética , Proteínas de Ligação a Telômeros/metabolismoRESUMO
Fork reversal is a conserved mechanism to prevent stalled replication forks from collapsing. Formation and protection of reversed forks are two crucial steps in ensuring fork integrity and stability. Five RAD51 paralogs, namely, RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3, which share sequence and structural similarity to the recombinase RAD51, play poorly defined mechanistic roles in these processes. Here, using purified BCDX2 (RAD51BCD-XRCC2) and CX3 (RAD51C-XRCC3) complexes and in vitro reconstituted biochemical systems, we mechanistically dissect their functions in forming and protecting reversed forks. We show that both RAD51 paralog complexes lack fork reversal activities. Whereas CX3 exhibits modest fork protection activity, BCDX2 significantly synergizes with RAD51 to protect DNA against attack by the nucleases MRE11 and EXO1. DNA protection is contingent upon the ability of RAD51 to form a functional nucleoprotein filament on DNA. Collectively, our results provide evidence for a hitherto unknown function of RAD51 paralogs in synergizing with RAD51 nucleoprotein filament to prevent degradation of stressed replication forks.
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Replicação do DNA , Rad51 Recombinase , Linhagem Celular , Cromossomos/metabolismo , DNA/genética , DNA/metabolismo , Nucleoproteínas/genética , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , HumanosRESUMO
The long non-coding telomeric RNA transcript TERRA, in the form of an RNA-DNA duplex, regulates telomere recombination. In a screen for nucleases that affects telomere recombination, mutations in DNA2, EXO1, MRE11 and SAE2 cause severe delay in type II survivor formation, indicating that type II telomere recombination is mediated through a mechanism similar to repairing double-strand breaks. On the other hand, mutation in RAD27 results in early formation of type II recombination, suggesting that RAD27 acts as a negative regulator in telomere recombination. RAD27 encodes a flap endonuclease that plays a role in DNA metabolism, including replication, repair and recombination. We demonstrate that Rad27 suppresses the accumulation of the TERRA-associated R-loop and selectively cleaves TERRA of R-loop and double-flapped structures in vitro. Moreover, we show that Rad27 negatively regulates single-stranded C-rich telomeric DNA circles (C-circles) in telomerase-deficient cells, revealing a close correlation between R-loop and C-circles during telomere recombination. These results demonstrate that Rad27 participates in telomere recombination by cleaving TERRA in the context of an R-loop or flapped RNA-DNA duplex, providing mechanistic insight into how Rad27 maintains chromosome stability by restricting the accumulation of the R-loop structure within the genome.
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Endonucleases Flap , Estruturas R-Loop , Proteínas de Saccharomyces cerevisiae , DNA Helicases/genética , DNA de Cadeia Simples , Endonucleases Flap/genética , Endonucleases Flap/metabolismo , Recombinação Genética , RNA/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Telômero/genética , Telômero/metabolismoRESUMO
BACKGROUND AND AIMS: Radiofrequency ablation (RFA) is an important curative therapy in hepatocellular carcinoma (HCC), but recurrence rate remains as high as all the other HCC therapeutic modalities. Methyltransferase 1 (METTL1), an enzyme for m 7 G tRNA modification, was reported to promote HCC development. Here, we assessed the role of METTL1 in shaping the immunosuppressive tumor microenvironment after insufficient RFA (iRFA). APPROACH AND RESULTS: By immunohistochemistry and multiplex immunofluorescence (mIF) staining, we showed that METTL1 expression was enhanced in post-RFA recurrent HCC, accompanied by increased CD11b + CD15 + polymorphonuclear-myeloid-derived suppressor cells (PMN-MDSCs) and decreased CD8 + T cells. Mechanistically, heat-mediated METTL1 upregulation enhanced TGF-ß2 translation to form the immunosuppressive environment by induction of myeloid-derived suppressor cell. Liver-specific overexpression or knockdown of Mettl1 significantly affected the accumulation of PMN-MDSCs and subsequently affected CD8 + T cell infiltration. Complete RFA successfully eliminated the tumor, whereas iRFA-treated mice exhibited enhanced tumor growth and metastasis with increased PMN-MDSC accumulation and decreased CD8 + T cells compared to sham surgery. Interrupting METTL1-TGF-ß2-PMN-MDSC axis by anti-Ly6G antibody, or knockdown of hepatoma-intrinsic Mettl1 or Tgfb2 , or TGF-ß signaling blockade significantly mitigated tumor progression induced by iRFA and restored CD8 + T cell population. CONCLUSIONS: Our study sheds light on the pivotal role of METTL1 in modulating an immunosuppressive microenvironment and demonstrated that interrupting METTL1-TGF-ß2-PMN-MDSC axis could be a therapeutic strategy to restore antitumor immunity and prevent HCC recurrence after RFA treatment, meriting further clinical studies.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Células Supressoras Mieloides , Camundongos , Animais , Carcinoma Hepatocelular/metabolismo , Células Supressoras Mieloides/metabolismo , Neoplasias Hepáticas/patologia , Fator de Crescimento Transformador beta2/metabolismo , Microambiente TumoralRESUMO
BACKGROUND: The purpose of this propensity score matching (PSM) analysis was to compare the effects of preoperative transcatheter arterial chemoembolization (TACE) and non-TACE on the long-term survival of patients who undergo radical hepatectomy. METHODS: PSM analysis was performed for 387 patients with hepatocellular carcinoma (HCC) (single > 3 cm or multiple) who underwent radical resection of HCC at our centre from January 2011 to June 2018. The patients were allocated to a preoperative TACE group (n = 77) and a non-TACE group (n = 310). The main outcome measures were progression-free survival (PFS) and overall survival (OS) since the treatment date. RESULTS: After PSM, 67 patients were included in each of the TACE and non-TACE groups. The median PFS times in the preoperative TACE and non-TACE groups were 24.0 and 11.3 months, respectively (p = 0.0117). The median OS times in the preoperative TACE and non-TACE groups were 41.5 and 29.0 months, respectively (p = 0.0114). Multivariate Cox proportional hazard regression analysis revealed that preoperative TACE (hazard ratio, 1.733; 95% CI, 1.168-2.570) and tumour thrombosis (hazard ratio, 0.323; 95% CI, 0.141-0.742) were independent risk factors significantly associated with OS. CONCLUSIONS: Preoperative TACE is related to improving PFS and OS after resection of HCC. Preoperative TACE and tumour thrombus volume were also found to be independent risk factors associated with OS.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Pontuação de Propensão , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Intrahepatic cholangiocarcinoma (ICC) is a deadly cancer with rapid tumor progression. While hyperactive mRNA translation caused by mis-regulated mRNA or tRNA modifications promotes ICC development, the role of rRNA modifications remains elusive. Here, we found that 18S rRNA m6A modification and its methyltransferase METTL5 were aberrantly upregulated in ICC and associated with poorer survival (log rank test, p < 0.05). We further revealed the critical role of METTL5-mediated 18S rRNA m6A modification in regulation of ICC cell growth and metastasis using loss- and gain-of function assays in vitro and in vivo. The oncogenic function of METTL5 is corroborated using liver-specific knockout and overexpression ICC mouse models. Mechanistically, METTL5 depletion impairs 18S rRNA m6A modification that hampers ribosome synthesis and inhibits translation of G-quadruplex-containing mRNAs that are enriched in the transforming growth factor (TGF)-ß pathway. Our study uncovers the important role of METTL5-mediated 18S rRNA m6A modification in ICC and unravels the mechanism of rRNA m6A modification-mediated oncogenic mRNA translation control.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Animais , Camundongos , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , Colangiocarcinoma/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/metabolismo , Biossíntese de Proteínas , Linhagem Celular TumoralRESUMO
BACKGROUND: This study was to compare the safety and efficacy of different lymphadenectomy methods in patients with pancreatic head cancer undergoing pancreaticoduodenectomy (PD). MATERIAL AND METHODS: A total of 150 patients were included in this study. Patients were divided into Group A (n = 79), Group B (n = 44), and Group C (n = 27) according to the different lymphadenectomy methods. The clinical endpoint was time to progression (TTP) and overall survival (OS). Postoperative complications of different lymphadenectomy methods were compared respectively. TTP and OS of the three groups were compared by Kaplan-Meier curves. RESULTS: There were no significant differences between the three groups in operative time (P = 0.300), death in the hospital (P = 0.253), postoperative hemorrhage (P = 0.863), postoperative pancreatic fistula (POPF) B/C (P = 0.306), bile leakage (P = 0.215), intestinal fistula (P = 0.177), lymphatic leakage (P = 0.267), delayed gastric emptying [(DGE) (P = 0.283)], ICU stay (P = 0.506), and postoperative hospital stay [(PHS) (P = 0.810)]. Median TTP in Groups B and C was significantly longer than in Group A (log-rank test, A vs B: P = 0.0005, A vs C: P = 0.0001). Median OS between the three groups has no statistical difference (P = 0.1546). CONCLUSIONS: Extended lymphadenectomy methods based on the TRIANGLE do not increase perioperative complications significantly and can effectively delay tumor progression in patients with pancreatic head cancer.
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Pâncreas , Neoplasias Pancreáticas , Humanos , Pâncreas/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Fístula Pancreática/etiologia , Complicações Pós-Operatórias/etiologia , Excisão de Linfonodo/métodosRESUMO
PURPOSE: The aim of this study was to investigate the distribution of coronal plane alignment of the knee (CPAK) classification and functional knee phenotypes in a Chinese osteoarthritis (OA) population and to compare different lower limb alignment targets according to the distribution characteristics to find suitable total knee arthroplasty (TKA) bone cut strategies for the Chinese OA patients. METHODS: The computed tomography (CT) images were retrospectively collected and the three-dimensional (3D) models were reconstructed from 434 Chinese OA patients, including 93 males and 341 females, with a mean age of 66.4 ± 9.3 years. Femoral mechanical angle (FMA), tibial mechanical angle (TMA) and mechanical hip-knee-ankle angle (mHKA) were measured on the 3D models. Arithmetic hip-knee-ankle angle (aHKA) was calculated using FMA plus TMA, and joint line obliquity was calculated as 180 + TMA-FMA. The CPAK according to MacDessi and the functional knee phenotypes according to Hirschmann were performed. In addition, the suitable TKA bone cut strategies were explored according to the phenotypes and based on the characteristics of different alignment targets, such as mechanical alignment, anatomic alignment (AA), kinematic alignment, restricted KA (rKA) and adjusted MA (aMA). Statistical differences were determined using the independent-samples t-test or the two independent-samples Wilcoxon test, with p < 0.05 considered statistically significant. RESULTS: The Chinese OA population showed a varus alignment tendency (mHKA = 172.1° ± 7.2°), to which the TMA was a major contributor (TMA = 84.7° ± 4.4° vs. FMA = 91.3° ± 3.2°). The mHKA was on average 3.9° more varus than the aHKA. A total of 140 functional knee phenotypes were found and 45.6% were concentrated in VARFMA3°-NEUFMA0° to VARTMA3°-NEUTMA0°. More than 70% of patients had different FMA and TMA phenotypes. There were 92.9% of CPAK distributed in types I to IV, with type I accounting for 53.9%. The FMA phenotypes were less changed if the aMA and rKA were chosen, and the TMA phenotypes were less changed if the AA and rKA were chosen. CONCLUSION: Compared with the CPAK, the functional knee phenotypes were more suitable for the Chinese OA population with a wide distribution and a varus tendency, and it seemed more appropriate to choose aMA and rKA as TKA alignment targets for resection. LEVEL OF EVIDENCE: Level â ¢.
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Artroplastia do Joelho , Imageamento Tridimensional , Osteoartrite do Joelho , Fenótipo , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Idoso , Osteoartrite do Joelho/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Pessoa de Meia-Idade , Artroplastia do Joelho/métodos , Estudos Retrospectivos , China , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Povo Asiático , População do Leste AsiáticoRESUMO
Acupoint drug delivery is a traditional external therapy of traditional Chinese medicine(TCM). Guided by the meridian and collateral theory in TCM, it applies medications to the skin at acupoints, exerting a dual therapeutic effect by stimulating the acupoints and the conduction of meridians. Acupoint drug delivery is widely used in clinical practice. Different from traditional oral admi-nistration and injection, it absorbs medications through the skin, effectively avoiding the first-pass effect of drugs and the toxic side effects caused by injection. Acupoint selection and transdermal drug absorption are pivotal factors affecting the efficacy of acupoint drug delivery. Recent research on acupoint drug delivery mainly focuses on the evaluation of clinical efficacy, yet the systematic investigations on acupoint selection and pharmacodynamic factors are scarce. This study reviews the mechanism, efficacy evaluation and application status of acupoint drug delivery. It integrates the theory of TCM with modern medicine to explore the mechanism of acupoint drug delivery, evaluate its clinical efficacy, and assess the transdermal penetration in vivo and in vitro. The application status of acupoint drug delivery is also summarized, including the selection of acupoints, application dosage form, application time and the absorption of acupoints. This review aims to offer insights and references for the research, development and clinical application of acupoint drug delivery products.
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Pontos de Acupuntura , Sistemas de Liberação de Medicamentos , Humanos , Sistemas de Liberação de Medicamentos/métodos , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Absorção Cutânea/efeitos dos fármacos , Meridianos , Medicina Tradicional Chinesa , Administração CutâneaRESUMO
This paper investigates the impact of Pd/Ni modification on the photocatalytic hydrogen production performance of SrTiO3(STO). STO catalysts were synthesized using a hydrothermal method, and Pd/Ni modification was applied on the surface of STO through chemical deposition. Experimental results demonstrate that the hydrogen evolution rate of Pd/Ni-modified STO (Pd/Ni-STO) reaches 2232.14µmol g-1h-1. X-ray absorption fine structure spectroscopy analysis reveals substitutional doping of Ni with Ti and coordination of Pd with surface O. X-ray photoelectron spectroscopy analysis indicates the introduction of oxygen vacancies due to Pd/Ni doping. Density functional theory calculations suggest that Ni doping activates neighboring Ti atoms, leading to the formation of bimetallic catalytic sites composed of oxygen vacancies and Ti atoms, greatly enhancing the photocatalytic hydrogen evolution performance. This study not only provides an effective catalyst for photocatalytic applications but also offers insights into the underlying mechanism, which may stimulate the development of metal-doped catalytic materials and have implications for a range of other applications.
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BACKGROUND AND OBJECTIVE: Laparoscopic hepatectomy approaches, including major hepatectomy, were rapidly developed in the past decade. However, standard laparoscopic left hemihepatectomy (LLH) is still only performed in high-volume medical centres. In our series, we describe our technical details and surgical outcomes of LLH. METHODS: Thirty-nine patients who underwent LLH in our institute were enrolled in the study. Among these, 13 patients underwent LLH guided by real-time ICG fluorescence imaging using the Arantius-first approach (ICG-LLH group), and the other 26 underwent conventional LLH (conventional LLH group). Demographic characteristics and perioperative data were retrospectively collected and analysed. We compared the technical and postoperative short-term outcomes of the two groups. RESULTS: There were no significant differences in the demographic or clinicopathological characteristics of the patients in the two groups. ICG-LLH required significantly fewer pringle manoeuvres (1 vs. 3 times, p < 0.0001), had a shorter parenchyma dissection time (26 vs. 78 min, p < 0.001), and required fewer vessel clips (18 vs. 28, p < 0.001). Although there was no significant difference, the ICG-LLH group had less bile leakage (0 vs. 5, p = 0.09) and less blood loss (120 vs. 165, p = 0.119). There were no significant differences in the overall complication or R0 resection rates between the two groups. CONCLUSION: Our data demonstrate that laparoscopic left hemihepatectomy guided by real-time ICG fluorescence imaging using the Arantius-first approach is safe and feasible in selected patients, thus improving the fluency of the surgical procedure and postoperative short-term outcomes.
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Hepatectomia , Laparoscopia , Humanos , Verde de Indocianina , Estudos Retrospectivos , Imagem ÓpticaRESUMO
BACKGROUND AND OBJECTIVE: It is controversial whether wrapping around the pancreaticojejunostomy (PJ) could reduce the rate of postoperative pancreatic fistula (POPF), especially in laparoscopic pancreaticoduodenectomy (LPD). This study aims to summarize our single-center initial experience in wrapping around PJ using the ligamentum teres hepatis (LTH) and demonstrate the feasibility and safety of this method. METHODS: Patients who underwent LPD applying the procedure of wrapping around the PJ were identified. The cohort was compared to the cohort with standard non-wrapping PJ. A 1:1 propensity score matching (PSM) was performed to compare the early postoperative outcomes of the two cohorts. Risk factors for POPF were determined by using univariate and multivariate logistic regression analysis. RESULTS: Overall, 143 patients were analyzed (LPD without wrapping (n = 91) and LPD with wrapping (n = 52)). After 1:1 PSM, 48 patients in each cohort were selected for further analysis. Bile leakage, DGE, intra-abdominal infection, postoperative hospital stays, harvested lymph nodes, and R0 resection were comparable between the two cohorts. However, the wrapping cohort was associated with significantly less POPF B (1 vs 18, P = 0.003), POPF C (0 vs 8, P = 0.043), and Clavien-Dindo classification level III-V (5 vs 26, P = 0.010). No patients died due to the clinically relevant POPF in the two cohorts. No patients who underwent the LTH wrapping procedure developed complications directly related to the wrapping procedure. After PSM, whether wrapping was an independent risk factor for POPF (OR = 0.202; 95%CI:0.080-0.513; P = 0.001). CONCLUSIONS: Wrapping the LTH around the PJ technique for LPD was safe, efficient, and reproducible with favorable perioperative outcomes in selected patients. However, further validations using high-quality RCTs are still required to confirm the findings of this study.
Assuntos
Laparoscopia , Ligamento Redondo do Fígado , Humanos , Pancreaticojejunostomia/efeitos adversos , Pancreaticojejunostomia/métodos , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Ligamento Redondo do Fígado/cirurgia , Pontuação de Propensão , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Laparoscopia/efeitos adversos , Estudos RetrospectivosRESUMO
PURPOSE: Femoral bowing influences the genesis and management of knee osteoarthritis (OA). The aim of this study was to investigate the relationship between the femoral torsion angle (FTA) and femoral bowing angle (FBA) in a southern Chinese population. It was hypothesized that a greater FTA would lead to a greater lateral FBA. METHODS: A total of 381 lower extremities from 381 osteoarthritic patients (298 women, 83 men; 201 left, 180 right; mean age 66.5 ± 8.9 years) were retrospectively reviewed. Age, sex, body mass index (BMI), side, height, femoral length (FL), hip-knee-ankle angle (HKA) and FTA were set as FBA-related factors. The three-dimensional (3D) FBA, the angle between the anatomical axis of the proximal femur and the anatomical axis of the distal femur in the plane they form, and its projection on the coronal (lateral FBA) and sagittal (anterior FBA) planes were measured on 3D computed tomography (CT) models. The correlation of the 3D, lateral and anterior FBAs with each of the FBA-related factors was explored using multiple linear regression analysis. The correlation between the FBA and FTA was explored and verified after using propensity score matching to control for the other FBA-related factors. RESULTS: The mean lateral and anterior FBAs were 5.5°, with 53.5% greater than 5°, and 12.7°, with 70.3% greater than 11°, respectively. 3D FBA was positively correlated with age (Std.Co = 0.113, P < 0.05) and HKA (Std.Co = 0.129, P < 0.05). Lateral FBA was positively correlated with age (Std.Co = 0.118, P < 0.05), female sex (Std.Co = 0.206, P < 0.05), HKA (Std.Co = 0.184, P < 0.05) and FL (Std.Co = 0.220, P < 0.05). Anterior FBA was positively correlated with age (Std.Co = 0.108, P < 0.05) and male sex (Std.Co = 0.108, P < 0.05). When the related factors were balanced between the two groups (NS), FTA did not significantly affect 3D FBA or anterior FBA (NS), while FTA was positively correlated with lateral FBA (Std.Co = 0.165, P < 0.05). CONCLUSION: External torsion of the proximal femur increases the lateral FBA by twisting a partial anterior FBA into a lateral FBA, especially in the female population. If a patient is found to have a large lateral FBA preoperatively, one should be alert to the possibility of a concomitant large FTA, as there are implications for femoral orthopedics, TKA and patellofemoral pressure distribution. LEVEL OF EVIDENCE: III.
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Genu Varum , Osteoartrite do Joelho , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
Contamination, hazard level and source of 10 widely concerned potentially toxic metal(loid)s (PTMs) Co, As, Pb, Cr, Cu, Zn, Ni, Mn, Ba, and V in fine dust with particle size below 63 µm (FD63) were investigated to assess the environmental quality of college campuses and influencing factors. PTMs sources were qualitatively analyzed using statistical methods and quantitatively apportioned using positive matrix factorization. Probabilistic contamination degrees of PTMs were evaluated using enrichment factor and Nemerow integrated enrichment factor. Eco-health risk levels of content-oriented and source-oriented for PTMs were evaluated using Monte Carlo simulation. Mean levels of Zn (643.8 mg kg-1), Pb (146.0 mg kg-1), Cr (145.9 mg kg-1), Cu (95.5 mg kg-1), and Ba (804.2 mg kg-1) in FD63 were significantly larger than soil background values. The possible sources of the concerned PTMs in FD63 were traffic non-exhaust emissions, natural source, mixed source (auto repair waste, paints and pigments) and traffic exhaust emissions, which accounted for 45.7%, 25.4%, 14.5% and 14.4% of total PTMs contents, respectively. Comprehensive contamination levels of PTMs were very high, mainly caused by Zn pollution and non-exhaust emissions. Combined ecological risk levels of PTMs were low and moderate, chiefly caused by Pb and traffic exhaust emissions. The non-cancer risks of the PTMs in FD63 to college students fell within safety level, while the carcinogenic PTMs in FD63 had a certain cancer risks to college students. The results of source-specific health risk assessment indicated that Cr and As were the priority PTMs, and the mixed source was the priority pollution source of PTMs in FD63 from college campuses, which should be paid attention to by the local government.
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Metais Pesados , Poluentes do Solo , Humanos , Metais Pesados/análise , Monitoramento Ambiental/métodos , Poeira/análise , Chumbo , Método de Monte Carlo , Poluentes do Solo/análise , Medição de Risco , China , CidadesRESUMO
OBJECTIVE: To establish a method for the determination of three furfural compounds in coffee and its products by gas chromatography-tandem mass spectrometry. METHODS: The samples were extracted with ethanol water(1â¶2, Vâ¶V) solution, ultrasonic with 10% Na_2CO_3 solution for 5 min, purified with 100 mg C_(18), 50 mg Srong Cation exchang(SCX), 150 mg anhydrous MgSO_4, separated by HP-INNOWAX capillary column(30 m×0.25 mm, 0.25 µm), detected by gas chromatography-tandem mass spectrometry, and quantified by isotope internal standard method. RESULTS: The correlation coefficients(r) of the three furfural compounds were all greater than 0.999, the limits of detection were 0.004-0.011 mg/kg, and the limits of quantitation were 0.013-0.031 mg/kg. The average recoveries were 86.0%-112% and the relative standard deviations were 4.1%-10.6%(n=6), at 3 supplemental levels in 3 different coffee substrates. Nine samples of coffee beans, instant coffee and coffee drinks were tested, and all three components to be tested were detected. CONCLUSION: The method is simple, rapid, sensitive, with good accuracy and precision. It is suitable for the determination of three furfural compounds in coffee and its products.
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Furaldeído , Espectrometria de Massas em Tandem , Cromatografia Gasosa-Espectrometria de Massas , Alimentos , Isótopos , Cromatografia Líquida de Alta PressãoRESUMO
Molecular catalysts (metal complexes), with molecularly defined uniform active sites and atomically precise structural tailorability allowing for regulating catalytic performance through metal- and ligand-centered engineering and elucidating reaction mechanisms via routine photoelectrochemical characterizations, have been increasingly explored for electrocatalytic CO2 reduction (ECR). However, their poor stability and low catalytic current density are undesirable for practical applications. Heterogenizing discrete molecular catalysts can potentially surmount these issues, and the resulting integrated catalysts largely share catalytical properties with their discrete molecular counterparts, which bridge the gap between heterogeneous and homogeneous catalysis and combine their advantages. This minireview surveys advances in design and regulation of molecular catalysts such as porphyrin, phthalocyanine, and bipyridine-based metal complexes and their integrated catalytic materials for selective ECR.
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BACKGROUND: There is the most common method for arthroscopic anterior cruciate ligament (ACL) reconstruction by using the semitendinosus and gracilis tendons and single-tunnel technique. However, anatomic translocation of hamstring tendon attachment is very rare. CASE PRESENTATION: A 45-year-old male who need to receive right knee ACL reconstruction due to sprain injury while playing table tennis was found to have a translocation at tibial attachment of semitendinosus tendon. The tibial insertion of left semitendinosus was then explored by ultrasound and found to be identical to the contralateral limb. The patient has a history of bilateral tibial lengthening. CONCLUSIONS: This is the first case as far as we know that reported anatomic translocation of the tibial attachment of the hamstring tendon after tibial lengthening. Surgeons should be aware of this specific situation when hamstring tendon need to be harvested to avoid unnecessary complications.
Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Músculos Isquiossurais , Tendões dos Músculos Isquiotibiais , Masculino , Humanos , Pessoa de Meia-Idade , Tendões dos Músculos Isquiotibiais/diagnóstico por imagem , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/métodos , Tendões/cirurgia , Tendões/transplante , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Lesões do Ligamento Cruzado Anterior/cirurgiaRESUMO
In recent years, more and more countries are focusing on the control of mining sites and the surrounding ecological environment, and the new environmental concept of green mines has been proposed. By investigating the ecological background of a mine site, pollution and ecological imbalances in the mine can be predicted, managed or transformed. This study investigated the effects of rare earth elements on plant growth in the Baotou Bayan Obo Rare Earth Mine and evaluated soil contamination and subsequent remediation through the measured plant height. Using linear regression, BP(Back Propagation) neural networks, GA-BP(Genetic Algorithm- Back Propagation) neural networks, ELM(Extreme Learning Machine) and GA-ELM(Genetic Algorithm- Extreme Learning Machine) model prediction instruments, the different rare earth solution concentrations were set as input values and the heights of Artemisia desertorum, which as the model plant, were set as output values in the prediction. The results showed that the linear regression predicted the standard error of single La(III), Ce(III) solution and compound La(III) + Ce(III) solution for Artemisia desertorum growth stress was on the high side, 7.02%- 8.92%; the efficiency range of each group of models under BP neural network, GA-BP neural network and ELM neural network were 1.15%- 2.53%, 0.85%- 1.28%, 1.76%- 3.53%; while the efficiency range under GA-ELM neural network was 0.59%- 0.68%, with average error values and predicted values close to the true values. Among them, the MAPE of GA-ELM neural network are significantly lower than other models, and the error decreases with increasing concentration of the compound solution. So GA-ELM neural network can be used as an efficient, fast and reasonable optimal model for predicting the growth stress of Artemisia desertorum in Bayan Obo mining area. The experimental results can provide a theoretical basis for assessing the risk of soil rare earth contamination in the area, evaluating the expectation of later remediation, and provide a degree of new ideas for the construction of green mines.
Assuntos
Artemisia , Aprendizagem , Modelos Lineares , Redes Neurais de Computação , Desenvolvimento VegetalRESUMO
PURPOSE: To achieve the desired alignment more accurately and improve postoperative outcomes, new techniques such as computer navigation (Navigation), patient-specific instruments (PSI) and surgical robots (Robot) are applied in Total Knee Arthroplasty (TKA). This network meta-analysis aims to compare the radiological and clinical outcomes among the above-mentioned techniques and conventional instruments (CON). METHODS: A PRISMA network meta-analysis was conducted and study protocol was published online at INPLASY (INPLASY202060018). Three databases (PubMed, EMBASE and Cochrane) were searched up to June 1, 2020. Randomised controlled trials (RCTs) comparing any two of the four techniques were included. A Bayesian network meta-analysis was performed focusing on radiological and clinical outcomes. The odds ratio (OR) or mean difference (MD) in various outcomes were calculated, and the interventions were ranked by the surface under the cumulative ranking area (SUCRA) value. RESULTS: Seventy-three RCTs were included, with a total of 4209 TKAs. Navigation and Robot could significantly reduce the occurrence of malalignment and malposition compared with PSI and CON, and Navigation could obtain higher medium-and-long-term KSS knee scores than CON. Robot had the greatest advantage in achieving the desired alignment accurately, followed by Navigation; Navigation had the greatest advantage in the KSS score. CONCLUSION: Navigation and Robot did improve the accuracy of alignment compared with PSI and conventional instrument in TKA, but the above four techniques showed no clinical significance in postoperative outcomes. LEVEL OF EVIDENCE: I.