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1.
Int J Mol Sci ; 25(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38673996

RESUMO

Gene function verification is a crucial step in studying the molecular mechanisms regulating various plant life activities. However, a stable and efficient homologous genetic transgenic system for herbaceous peonies has not been established. In this study, using virus-induced gene silencing technology (VIGS), a highly efficient homologous transient verification system with distinctive advantages was proposed, which not only achieves true "intact-plant" infiltration but also minimizes the operation. One-year-old roots of the representative species, Paeonia lactiflora Pall., were used as the materials; prechilling (4 °C) treatment for 3-5 weeks was applied as a critical precondition for P. lactiflora to acquire a certain chilling accumulation. A dormancy-related gene named HOMEOBOX PROTEIN 31 (PlHB31), believed to negatively regulate bud endodormancy release (BER), was chosen as the target gene in this study. GFP fluorescence was detected in directly infiltrated and newly developed roots and buds; the transgenic plantlets exhibited remarkably earlier budbreak, and PlHB31 was significantly downregulated in silenced plantlets. This study established a homologous transient silencing system featuring intact-plant infiltration and minimized manipulation for gene function research, and also offers technical support and serves as a theoretical basis for gene function discovery in numerous other geophytes.


Assuntos
Regulação da Expressão Gênica de Plantas , Inativação Gênica , Raízes de Plantas , Plantas Geneticamente Modificadas , Plantas Geneticamente Modificadas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Paeonia/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo
2.
Phys Rev Lett ; 130(9): 095101, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930918

RESUMO

We report on charge state measurements of laser-accelerated carbon ions in the energy range of several MeV penetrating a dense partially ionized plasma. The plasma was generated by irradiation of a foam target with laser-induced hohlraum radiation in the soft x-ray regime. We use the tricellulose acetate (C_{9}H_{16}O_{8}) foam of 2 mg/cm^{3} density and 1 mm interaction length as target material. This kind of plasma is advantageous for high-precision measurements, due to good uniformity and long lifetime compared to the ion pulse length and the interaction duration. We diagnose the plasma parameters to be T_{e}=17 eV and n_{e}=4×10^{20} cm^{-3}. We observe the average charge states passing through the plasma to be higher than those predicted by the commonly used semiempirical formula. Through solving the rate equations, we attribute the enhancement to the target density effects, which will increase the ionization rates on one hand and reduce the electron capture rates on the other hand. The underlying physics is actually the balancing of the lifetime of excited states versus the collisional frequency. In previous measurement with partially ionized plasma from gas discharge and z pinch to laser direct irradiation, no target density effects were ever demonstrated. For the first time, we are able to experimentally prove that target density effects start to play a significant role in plasma near the critical density of Nd-glass laser radiation. The finding is important for heavy ion beam driven high-energy-density physics and fast ignitions. The method provides a new approach to precisely address the beam-plasma interaction issues with high-intensity short-pulse lasers in dense plasma regimes.

3.
Gynecol Oncol ; 171: 1-8, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36804610

RESUMO

OBJECTIVE: To analyze the methods, feasibility, efficiency, and fertility outcomes of fertility-sparing treatment for patients with placental site trophoblastic tumor (PSTT). METHODS: Clinical data of patients diagnosed with PSTT between April 1998 and April 2020 from Peking Union Medical College Hospital (PUMCH) were retrospectively collected. The clinical features, treatment, and outcomes of patients received fertility-sparing treatment were analyzed and compared with patients suffered hysterectomy. RESULTS: In total, 126 patients were included in the study and 29 of them received fertility-sparing treatment. Besides significantly younger age and lower proportion of antecedent term delivery were seen in fertility-sparing group than hysterectomy group, no significant differences were observed in stage, serum ß-hCG level, or interval from antecedent pregnancy between the two groups. Conservative surgery was selected individualized and none of them suffered salvage hysterectomy. Patients with clinical or pathological high-risk factors received adjuvant chemotherapy, yet the fertility-sparing treatment did not significantly lengthen chemotherapy duration. All patients in fertility-sparing group achieved complete remission without relapse after 36 to 176 months of follow-up and had sixteen healthy term delivery more than one year after the treatment. CONCLUSIONS: Fertility-sparing treatment for PSTT can be considered for young patients with localized uterine lesions who strongly desire to preserve their fertility potential. With individualized conservative surgery and selected adjuvant chemotherapy, fertility-sparing treatment will not influence the risk of relapse or overall survival and patients will achieve favorable pregnancy and live birth outcomes.


Assuntos
Tumor Trofoblástico de Localização Placentária , Neoplasias Uterinas , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/cirurgia , Tumor Trofoblástico de Localização Placentária/cirurgia , Recidiva Local de Neoplasia , Placenta/patologia
4.
Postgrad Med J ; 99(1172): 529-534, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319161

RESUMO

Lumbar disc herniation (LDH) is one of the most common causes of lumbocrural pain. In the past 20 years, the incidence of LDH has increased dramatically. There are many treatments for LDH, including conservative treatment (such as acupuncture and physiotherapy), minimally invasive interventional treatment (such as collagenase chemonucleolysis and radiofrequency ablation) and surgical treatment. The main purpose of this paper is to review the development process and application status of collagenase chemonucleolysis in the treatment of LDH at home and abroad and provide a reference for clinical treatment.


Assuntos
Quimiólise do Disco Intervertebral , Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/tratamento farmacológico , Deslocamento do Disco Intervertebral/cirurgia , Dor/tratamento farmacológico , Tratamento Conservador , Colagenases/uso terapêutico , Resultado do Tratamento
5.
Postgrad Med J ; 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37035936

RESUMO

Lumbar disc herniation (LDH) is one of the most common causes of lumbocrural pain. In the past 20 years, the incidence of LDH has increased dramatically. There are many treatments for LDH, including conservative treatment (such as acupuncture and physiotherapy), minimally invasive interventional treatment (such as collagenase chemonucleolysis and radiofrequency ablation) and surgical treatment. The main purpose of this paper is to review the development process and application status of collagenase chemonucleolysis in the treatment of LDH at home and abroad and provide a reference for clinical treatment.

6.
Sensors (Basel) ; 23(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37430614

RESUMO

To improve the quality and efficiency of robot grinding, a design and a control algorithm for a robot used for grinding the surfaces of large, curved workpieces with unknown parameters, such as wind turbine blades, are proposed herein. Firstly, the structure and motion mode of the grinding robot are determined. Secondly, in order to solve the problem of complexity and poor adaptability of the algorithm in the grinding process, a force/position hybrid control strategy based on fuzzy PID is proposed which greatly improves the response speed and reduces the error of the static control strategy. Compared with normal PID, fuzzy PID has the advantages of variable parameters and strong adaptability; the hydraulic cylinder used to adjust the angle of the manipulator can control the speed offset within 0.27 rad/s, and the grinding process can be carried out directly without obtaining the specific model of the surface to be machined. Finally, the experiments are carried out, the grinding force and feed speed are maintained within the allowable error range of the expected value, and the results verify the feasibility and effectiveness of the position tracking and constant force control strategy in this paper. The surface roughness of the blade is maintained within Ra = 2~3 µm after grinding, which proves that the grinding quality meets the requirements of the best surface roughness required for the subsequent process.

7.
Eur Arch Otorhinolaryngol ; 279(9): 4595-4604, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35581439

RESUMO

PURPOSE: To investigate the prognostic value of histopathological differentiation for the survival of patients with laryngeal squamous cell carcinoma (LSCC). MATERIALS AND METHODS: Retrospective clinical and histopathological differentiation data on consecutive cases of LSCC from a single institution over a 10-years period were collected and analyzed in this study. Oncological outcomes were assessed based on disease-specific survival (DSS), disease-free survival (DFS), and overall survival (OS) using the Kaplan-Meier method and Cox proportional hazards regression analysis. Propensity score matching (PSM) was performed to reduce or eliminate the bias due to confounding variables. RESULTS: A total of 998 LSCC cases were identified in this study. As compared to well to moderately differentiated LSCC, poorly differentiated tumors had adjusted hazard ratios (aHRs) of 1.78 (95% confidence interval [CI] 1.31-2.43), 2.00 (95% CI 1.51-2.65), and 1.72 (95% CI 1.28-2.31) for DSS, DFS, and OS, respectively. The new patient cohort consisted of 138 patients with well to moderately differentiated LSCC and 138 patients with poorly differentiated LSCC after PSM. The survival outcomes of patients with well to moderately differentiated LSCCs were significantly better than those of patients with poorly differentiated tumors in DSS (aHR 1.91; 95% CI 1.24-2.95), DFS (aHR 2.07; 95% CI 1.37-3.12), and OS (aHR 2.14; 95% CI 1.39-3.28). CONCLUSION: This study showed that survival outcomes of patients with poorly differentiated LSCC were significantly worse than those of patients with well to moderately differentiated LSCC. In addition, histopathological differentiation is an important prognostic factor for LSCC survival. Therefore, further treatment plans should focus on poorly differentiated LSCC to improve the survival outcomes.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Carcinoma de Células Escamosas/patologia , Humanos , Neoplasias Laríngeas/cirurgia , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
8.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430818

RESUMO

The growing region of herbaceous peony (Paeonia lactiflora) has been severely constrained due to the intensification of global warming and extreme weather events, especially at low latitudes. Assessing and selecting stress-tolerant and high-quality peony germplasm is essential for maintaining the normal growth and application of peonies under adverse conditions. This study proposed a modified multi-criteria decision-making (MCDM) model for assessing peonies adapted to low-latitude climates based on our previous study. This model is low-cost, timesaving and suitable for screening the adapted peony germplasm under hot and humid climates. The evaluation was conducted through the analytic hierarchy process (AHP), three major criteria, including adaptability-related, ornamental feature-related and growth habits-related criteria, and eighteen sub-criteria were proposed and constructed in this study. The model was validated on fifteen herbaceous peonies cultivars from different latitudes. The results showed that 'Meiju', 'Hang Baishao', 'Hongpan Tuojin' and 'Bo Baishao' were assessed as Level I, which have strong growth adaptability and high ornamental values, and were recommended for promotion and application at low latitudes. The reliability and stability of the MCDM model were further confirmed by measuring the chlorophyll fluorescence of the selected adaptive cultivars 'Meiju' and 'Hang Baishao' and one maladaptive cultivar 'Zhuguang'. This study could provide a reference for the introduction, breeding and application of perennials under everchanging unfavorable climatic conditions.


Assuntos
Paeonia , Reprodutibilidade dos Testes , Melhoramento Vegetal , Plantas
9.
Cancer Invest ; 39(9): 734-740, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34232825

RESUMO

BACKGROUND: The purpose of this study was to compare survival outcomes in patients with perineural invasion (PNI)-positive laryngeal squamous cell carcinoma (LSCC) and patients with PNI-negative LSCC. METHODS: A total of 1,272 patients with LSCC, diagnosed between 2008 and 2017, were included in this study. LSCC Patients with and without PNI were matched based on possible confounding factors. Survival analysis was performed using Kaplan-Meier estimates and the Cox proportional hazards model. RESULTS: Of the 1,272 LSCC patients, 118 (9.28%) were positive for PNI. Compared to PNI-negative patients, PNI-positive LSCC patients had significantly worse overall survival (OS) (p = 0.017), disease-specific survival (DSS) (p = 0.034) and recurrence-free survival (RFS) (p = 0.002). After pair matching, cohorts consisted of 118 patients in the PNI-positive group and 118 in the PNI-negative group. Significantly increased risk of OS (HR, 2.17; 95% confidence interval [CI], 1.29-3.61, p = 0.003), DSS (HR, 2.07; 95% CI, 1.32-3.24, p = 0.004) and RFS (HR, 2.65; 95% CI, 1.59-4.40, p < 0.001) was observed after adjustment for prognostic variables. CONCLUSIONS: Patients with PNI-positive LSCC have significantly worse survival outcomes compared to patients with PNI-negative LSCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Laríngeas/patologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Nervos Periféricos/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Prognóstico , Modelos de Riscos Proporcionais
10.
BMC Cancer ; 21(1): 845, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294055

RESUMO

BACKGROUND: The understanding of molecular changes in mCRC during treatment could be used to personalise therapeutic strategies. The aim of our study was to explore the association of circulating tumour DNA (ctDNA) with clinical outcome in metastatic colorectal cancer (mCRC). METHODS: Sequential patients with mCRC receiving standard first-line chemotherapy were included prospectively. Both plasma ctDNA and serum CEA were assessed in samples obtained before treatment and after 4 cycles of chemotherapy (C4). Computed tomography (CT) scans were carried out at baseline and post-C4 (8-10 weeks) and were assessed using Response Evaluation Criteria In Solid Tumours version 1.1 (RECIST v1.1). Target-capture deep sequencing with a panel covering 1021 genes was performed to detected somatic mutations in ctDNA. RESULTS: A total of 20 patients were prospectively included and treated with either leucovorin, fluorouracil, and oxaliplatin (FOLFOX) (15/20) or leucovorin, fluorouracil, and irinotecan (FOLFIRI) (5/20). Median follow-up was 6.9 months (range 1.6-26.6). Somatic mutations for baseline ctDNA analysis were identified in 85% (17/20) of the patients. Mutation variations of ctDNA after chemotherapy were tested in 16/20 (80.0%) of the patients. In multivariate analyses, a high baseline molecular tumour burden index (mTBI) in ctDNA was associated with a higher risk of disease progression, as well as emergence of new mutations in ctDNA during chemotherapy. Patients with newly detected mutations had shorter progression-free survival (PFS) compared to those without (median 3.0 versus 7.3 months; hazard ratio (HR), 5.97; 95% confidence interval (CI), 0.70-50.69; P = 0.0003). Fold changes in mTBI from baseline to post-C4 were obtained in 80.0% (16/20) of the patients, which were also related to PFS. Patients with fold reduction in mTBI above 0.8-fold had longer PFS compared to those below (median 9.3 versus 4.1 months; HR, 4.51; 95% CI, 1.29-15.70; P = 0.0008). CONCLUSIONS: Newly detected mutations in ctDNA during treatment might potentially be associated with clinical outcome in mCRC and may provide important clinical information.


Assuntos
Biomarcadores Tumorais , DNA Tumoral Circulante , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Mutação , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/tratamento farmacológico , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Tomografia Computadorizada por Raios X
11.
BMC Anesthesiol ; 21(1): 284, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34781876

RESUMO

BACKGROUND: Suboptimal tissue perfusion and oxygenation may be the root cause of certain perioperative complications in neonates and infants having complicated aortic coarctation repair. Practical, effective, and real-time monitoring of organ perfusion and/or tissue oxygenation may provide early warning of end-organ mal-perfusion. METHODS: Neonates/infants who were scheduled for aortic coarctation repair with cardiopulmonary bypass (CPB) and selective cerebral perfusion (SCP) from January 2015 to February 2017 in Children's Hospital of Nanjing Medical University participated in this prospective observational study. Cerebral and somatic tissue oxygen saturation (SctO2 and SstO2) were monitored on the forehead and at the thoracolumbar paraspinal region, respectively. SctO2 and SstO2 were recorded at different time points (baseline, skin incision, CPB start, SCP start, SCP end, aortic opening, CPB end, and surgery end). SctO2 and SstO2 were correlated with mean arterial pressure (MAP) and partial pressure of arterial blood carbon dioxide (PaCO2). RESULTS: Data of 21 patients were analyzed (age=75±67 days, body weight=4.4±1.0 kg). SstO2 was significantly lower than SctO2 before aortic opening and significantly higher than SctO2 after aortic opening. SstO2 correlated with leg MAP when the measurements during SCP were (r=0.67, p<0.0001) and were not included (r=0.46, p<0.0001); in contrast, SctO2 correlated with arm MAP only when the measurements during SCP were excluded (r=0.14, p=0.08 vs. r=0.66, p<0.0001). SCP also confounded SctO2/SstO2's correlation with PaCO2; when the measurements during SCP were excluded, SctO2 positively correlated with PaCO2 (r=0.65, p<0.0001), while SstO2 negatively correlated with PaCO2 (r=-0.53, p<0.0001). CONCLUSIONS: SctO2 and SstO2 have distinct patterns of changes before and after aortic opening during neonate/infant aortic coarctation repair. SctO2/SstO2's correlations with MAP and PaCO2 are confounded by SCP. The outcome impact of combined SctO2/SstO2 monitoring remains to be studied.


Assuntos
Coartação Aórtica/cirurgia , Saturação de Oxigênio/fisiologia , Oxigênio/metabolismo , Pressão Arterial/fisiologia , Dióxido de Carbono/sangue , Ponte Cardiopulmonar/métodos , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pressão Parcial , Estudos Prospectivos
12.
Arch Gynecol Obstet ; 304(4): 1043-1053, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33751209

RESUMO

OBJECTIVE: The aim of the study was to investigate the relative risk factors associated with the prognosis and effective treatments of alpha-fetoprotein (AFP)-producing epithelial ovarian carcinoma (EOC). METHOD: We presented three cases of AFP-producing EOC and performed a brief review to summarize the clinicopathological features and prognostic factors of 24 cases that have been previously reported. We evaluated the correlations among prognostic and clinical parameters, such as stage, pathology and chemotherapy regimens. In addition, a retrospective review of these 27 cases was conducted, and survival curves were estimated using the Kaplan-Meier method. RESULTS: The patients were aged between 23 and 77 years. The median overall survival was 10 months, and ten (37.04%) patients died within 18 months. We compared the overall mean survival times of all patients in different stages, and the results suggest that the postoperative pathological staging is hardly correlated with prognosis (P = 0.76). There was a correlation between pathology and prognosis (P = 0.0018). The mean survival time was longer for patients who had undergone chemotherapy than for those without chemotherapy (14.88 vs 0.65 months) (P < 0.0001). Moreover, although patients had a good response to the regimens for PEB and TC (P = 0.004), there was no significant difference between PEB and TC (P = 0.386). CONCLUSIONS: AFP-producing EOC is uncommon and regarded as an extremely malignant type of tumor. Patients with chemotherapy may have a longer survival time; additionally, PEB and TC may be an optimal selection for this kind of tumor. Further large-scale studies are needed to confirm our findings.


Assuntos
Neoplasias Ovarianas , alfa-Fetoproteínas , Adulto , Idoso , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
13.
Environ Toxicol ; 36(4): 520-529, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33166055

RESUMO

Colorectal cancer stem cell (CSC) has been regarded to be the root of colorectal cancer progression. However, there is still no effective therapeutic method targeting colorectal CSC in clinical application. Here, we investigated the effects of dichloroacetate (DCA) on colorectal cancer cell stemness. We showed that DCA could reduce colorectal cancer cell stemness in a dose-dependent manner, which is evident by the decreased expression of stemness markers, tumor cell sphere-formation and cell migration ability. In addition, it was found that DCA trigerred the ferroptosis of colorectal CSC, which is characterized as the upregulation of iron concentration, lipid peroxides, and glutathione level, and decreased cell viability. Mechanistic studies demonstrated that DCA could sequester iron in lysosome and thus trigger ferroptosis, which is necessary for DCA-mediated attenuation on colorectal cancer cell stemness. Taken together, this work suggests that DCA might be a colorectal CSC-killer.


Assuntos
Neoplasias Colorretais/patologia , Ácido Dicloroacético/farmacologia , Ferroptose/efeitos dos fármacos , Ferro/metabolismo , Lisossomos/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Sequestrantes/farmacologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Relação Dose-Resposta a Droga , Células HCT116 , Células HT29 , Humanos , Lisossomos/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia
14.
Sensors (Basel) ; 21(8)2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33920238

RESUMO

Due to the fixed size of the structure or the possibility of only simple manual adjustment, the traditional toilet wheelchair cannot easily be adapted to the size of the user or the toilet. In this paper, a planar two-degree-of-freedom parallel mechanism with coupling branch chains is proposed to enable both seat height adjustment and body posture adjustment of a toilet chair, solving the problems of posture adaptability between the user and the machine, and height matching in the process of using the wheelchair-assisted toilet. The model of the parallel mechanism was designed after analyzing the general rules of posture transformation in the human body before and after the toilet process, and the dimensions of each linkage were then determined according to the constraint conditions. By analyzing the degree of freedom, kinematics, workspace, singularity and position of the center of gravity, the rationality of the design was ensured. The weighted average function was used to find the optimal fixed point of the horizontal moving slider, and the actual trajectory at the end of the single driving mode was close to the ideal trajectory. The experimental results show that the adjustable seat height range is 290~550 mm and the adjustable angle range is 0~90°, which can enable disabled people to use the toilet independently.


Assuntos
Aparelho Sanitário , Pessoas com Deficiência , Cadeiras de Rodas , Fenômenos Biomecânicos , Desenho de Equipamento , Humanos , Postura
15.
Sensors (Basel) ; 21(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34770562

RESUMO

A new method of kinematic analysis and singularity analysis is proposed for a 7-DOF redundant manipulator with three consecutive parallel axes. First, the redundancy angle is described according to the self-motion characteristics of the manipulator, the position and orientation of the end-effector are separated, and the inverse kinematics of this manipulator is analyzed by geometric methods with the redundancy angle as a constraint. Then, the Jacobian matrix is established to derive the conditions for the kinematic singularities of the robotic arm by using the primitive matrix method and the block matrix method. Then, the kinematic singularities conditions in the joint space are mapped to the Cartesian space, and the singular configuration is described using the end poses and redundancy angles of the robotic arm, and a singularity avoidance method based on the redundancy angles and end pose is proposed. Finally, the correctness and feasibility of the inverse kinematics algorithm and the singularity avoidance method are verified by simulation examples.


Assuntos
Algoritmos , Fenômenos Biomecânicos , Simulação por Computador , Movimento (Física)
16.
Int J Mol Sci ; 22(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34445086

RESUMO

The introduction of herbaceous peony (Paeonia lactiflora Pall.) in low-latitude areas is of great significance to expand the landscape application of this world-famous ornamental. With the hazards of climate warming, warm winters occurs frequently, which makes many excellent northern herbaceous peony cultivars unable to meet their chilling requirements (CR) and leads to their poor growth and flowering in southern China. Exploring the endodormancy release mechanism of underground buds is crucial for improving low-CR cultivar screening and breeding. A systematic study was conducted on P. lactiflora 'Meiju', a screened cultivar with a typical low-CR trait introduced from northern China, at the morphological, physiological and molecular levels. The CR value of 'Meiju' was further verified as 677.5 CUs based on the UT model and morphological observation. As a kind of signal transducer, reactive oxygen species (ROS) released a signal to enter dormancy, which led to corresponding changes in carbohydrate and hormone metabolism in buds, thus promoting underground buds to acquire strong cold resistance and enter endodormancy. The expression of important genes related to ABA metabolism, such as NCED3, PP2C, CBF4 and ABF2, reached peaks at the critical stage of endodormancy release (9 January) and then decreased rapidly; the expression of the GA2ox8 gene related to GA synthesis increased significantly in the early stage of endodormancy release and decreased rapidly after the release of ecodormancy (23 January). Cytological observation showed that the period when the sugar and starch contents decreased and the ABA/GA ratio decreased was when 'Meiju' bud endodormancy was released. This study reveals the endodormancy regulation mechanism of 'Meiju' buds with the low-CR trait, which lays a theoretical foundation for breeding new herbaceous peony cultivars with the low-CR trait.


Assuntos
Paeonia/crescimento & desenvolvimento , Dormência de Plantas , Clima , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Paeonia/genética , Paeonia/fisiologia , Melhoramento Vegetal , Estações do Ano
17.
Breast Cancer Res Treat ; 178(2): 275-281, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31388934

RESUMO

PURPOSE: Human epidermal growth factor receptor 2 (HER2) status is both an independent prognostic factor and a predictive factor for the efficacy of targeted therapy for breast cancer, so it is critical to accurately detect HER2 protein expression and/or gene amplification. According to the recommendations of the 2013 American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP) guidelines for HER2 breast cancer testing, an additional test should be pursued on a different block from the same tumor as one of the options for patients with immunohistochemistry (IHC) 2+ and a HER2/CEP17 ratio of < 2.0 with an average HER2 signals per tumor cell of ≥ 4.0 and < 6.0 by reflex test using dual-probe fluorescence in situ hybridization (FISH) (double-equivocal HER2). Our aim in this study is to explore the consistency of HER2 status between the two blocks. METHODS: We retrospectively analyzed 5685 primary invasive breast cancers between April 2015 and January 2019 from Peking Union Medical College Hospital. For cases with double-equivocal HER2 revealed in initial blocks, HER2 gene status was evaluated by FISH in a different block from the same tumor. The FISH score was interpreted according to the 2013 ASCO/CAP guidelines for HER2 testing. RESULTS: In our cohort of 5685 specimens, the overall HER2 IHC3+, 2+, 1+ and 0 cases were 20.5%, 31.8%, 28.3%, and 19.5%, respectively. Then, 13.7%, 66.3%, and 20.0% of HER2 amplification, non-amplification, and equivocation rates were found, respectively, in IHC2+ patients (n = 1777) by reflex FISH assay. For specimens with double-equivocal HER2 (n = 333), HER2 status was assessed in another block from the same tumor by FISH and then the frequency of HER2 positive, negative, and equivocation was estimated at 5.7%, 22.5%, and 71.8%, respectively. Because double-equivocal HER2 cases are classified in the HER2 negative category by the 2018 ASCO/CAP HER2 testing guidelines, only 1.3% (19/1511) of HER2 positive patients were determined through additional HER2 testing in another block from the HER2 negative population. CONCLUSIONS: HER2 status in different blocks from the same tumor in primary invasive breast cancer was highly concordant. Our data supported the recommendation of the 2018 ASCO/CAP HER2 testing guidelines in breast cancer to remove the suggestion for additional HER2 testing using another block contained in the previous version.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Povo Asiático , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , China/epidemiologia , Feminino , Amplificação de Genes , Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Neoplasias , Receptor ErbB-2/genética
18.
J Surg Res ; 236: 352-358, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30683458

RESUMO

BACKGROUND: Expanded polytetrafluoroethylene (ePTFE), an ideal bioimplant material, is commonly used in surgical repair to treat soft tissue defects and deformities. However, the main disadvantage of ePTFE is that its distinctive porous ultrastructure is prone to bacterial adhesion that gives rise to infection and chronic inflammation, resulting in functional failure. Herein, a potentially promising approach to ePTFE autologous vascularization (AV-ePTFE) in vivo was established and developed to enhance the material's antibacterial properties. METHODS: Hematoxylin and eosin (H&E) staining and visual observation were performed to validate the intensity of the inflammatory response and related histological changes in surgical wounds after AV-ePTFE implantation. In addition, the antibacterial activities of AV-ePTFE were assessed by an in vitro bacterial adhesion assay and scanning electron microscope observation. RESULTS: The optimal time point of AV-ePTFE was 12 weeks after implantation. AV-ePTFE relieved inflammation based on an inflammation grading evaluation and expedited wound healing. Furthermore, AV-ePTFE effectively reduced the number of bacterial adhesions, inhibited bacterial biofilm formation, and prevented the occurrence of infection. CONCLUSIONS: We conclude that autologous vascularization is an effective method to improve the antibacterial adhesion properties and biocompatibility of ePTFE after implantation and that it may have a significant effect on clinical application of future porous biomaterials.


Assuntos
Procedimentos de Cirurgia Plástica/efeitos adversos , Politetrafluoretileno/efeitos adversos , Infecção da Ferida Cirúrgica/prevenção & controle , Alicerces Teciduais/efeitos adversos , Enxerto Vascular/métodos , Animais , Bactérias/isolamento & purificação , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/química , Biofilmes/crescimento & desenvolvimento , Modelos Animais de Doenças , Feminino , Humanos , Testes de Sensibilidade Microbiana , Politetrafluoretileno/química , Porosidade , Ratos , Ratos Sprague-Dawley , Procedimentos de Cirurgia Plástica/instrumentação , Tela Subcutânea/irrigação sanguínea , Tela Subcutânea/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Alicerces Teciduais/química , Alicerces Teciduais/microbiologia , Transplante Autólogo/métodos , Resultado do Tratamento
19.
Jpn J Clin Oncol ; 49(7): 620-627, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220306

RESUMO

OBJECTIVE: Recurrent hydatidiform moles are reportedly biparental complete moles and related to mutated NLRP7 and KHDC3L. This study was designed to identify mutations of gene NLRP7 and KHDC3L in biparental complete moles. METHODS: In this study, we have screened NLRP7 and KHDC3L mutations in five patients with recurrent moles and five with sporadic moles. Molar tissues and blood samples were collected from patients and their partners. Genotypes of the molar tissues were determined based on short tandem repeat polymorphism. The coding exons of NLRP7 and KHDC3L were sequenced. RESULTS: Two patients with recurrent moles had biparental complete moles, while all other patients had androgenetic complete moles. Three non-synonymous variants in NLRP7 (c.955 G>A, c.1280 T>C and c.1441 G>A) and one in KHDC3L (c.602 C>G) were identified in patients with recurrent moles. NLRP7 c.1441 G>A and c.1280 T>C were mutations found in the Chinese population, while c.1441 G>A was only detected in patients with biparental complete moles in this study. CONCLUSIONS: Genotyping can be used to differentiate biparental complete moles from androgenetic moles and to predict the risk of recurrent moles in future pregnancies. NLRP7 c.1441 G>A may associate with biparental complete moles. Biparental complete moles exhibit genetic heterogeneity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Povo Asiático/genética , Mola Hidatiforme/genética , Mutação/genética , Recidiva Local de Neoplasia/genética , Proteínas/genética , Neoplasias Uterinas/genética , Adulto , Sequência de Bases , Feminino , Humanos , Mola Hidatiforme/patologia , Masculino , Repetições de Microssatélites/genética , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Gravidez
20.
BMC Anesthesiol ; 19(1): 84, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117960

RESUMO

BACKGROUND: Pierre Robin Sequence (PRS) patients are known for their triad of micrognathia, glossoptosis, and airway obstruction. Their airway can be a challenge even for the most experienced pediatric anesthesiologist. CASE PRESENTATION: We report the case of a 9 day old 3.5 kg boy diagnosed with PRS, cleft palate, and a vallecular cyst with severe upper airway obstruction. The combination of PRS, cleft palate and the presence of vallecular cyst made this a cascade reaction of difficult airway. Due to his unique anatomy, we didn't appreciate how difficult his airway was until multiple attempts with high-tech equipment failed. Ultimately it was the finger guide intubation, this old technique without any equipment, that rescued this patient from lose of airway. CONCLUSIONS: The boy was successfully rescued by finger guided intubation. Finger guide intubation should be added to the anesthesiologist's newborn rescue intubation training.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico por imagem , Obstrução das Vias Respiratórias/cirurgia , Intubação Intratraqueal/métodos , Síndrome de Pierre Robin/diagnóstico por imagem , Síndrome de Pierre Robin/cirurgia , Índice de Gravidade de Doença , Obstrução das Vias Respiratórias/etiologia , Fissura Palatina/complicações , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/cirurgia , Humanos , Imageamento Tridimensional/métodos , Recém-Nascido , Masculino , Síndrome de Pierre Robin/complicações
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