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1.
Med ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38677287

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in children and adolescents, particularly those with obesity. NAFLD is considered a hepatic manifestation of the metabolic syndrome due to its close associations with abdominal obesity, insulin resistance, and atherogenic dyslipidemia. Experts have proposed an alternative terminology, metabolic dysfunction-associated fatty liver disease (MAFLD), to better reflect its pathophysiology. This study aimed to develop consensus statements and recommendations for pediatric MAFLD through collaboration among international experts. METHODS: A group of 65 experts from 35 countries and six continents, including pediatricians, hepatologists, and endocrinologists, participated in a consensus development process. The process encompassed various aspects of pediatric MAFLD, including epidemiology, mechanisms, screening, and management. FINDINGS: In round 1, we received 65 surveys from 35 countries and analyzed these results, which informed us that 73.3% of respondents agreed with 20 draft statements while 23.8% agreed somewhat. The mean percentage of agreement or somewhat agreement increased to 80.85% and 15.75%, respectively, in round 2. The final statements covered a wide range of topics related to epidemiology, pathophysiology, and strategies for screening and managing pediatric MAFLD. CONCLUSIONS: The consensus statements and recommendations developed by an international expert panel serve to optimize clinical outcomes and improve the quality of life for children and adolescents with MAFLD. These findings emphasize the need for standardized approaches in diagnosing and treating pediatric MAFLD. FUNDING: This work was funded by the National Natural Science Foundation of China (82070588, 82370577), the National Key R&D Program of China (2023YFA1800801), National High Level Hospital Clinical Research Funding (2022-PUMCH-C-014), the Wuxi Taihu Talent Plan (DJTD202106), and the Medical Key Discipline Program of Wuxi Health Commission (ZDXK2021007).

2.
World J Gastroenterol ; 30(15): 2128-2142, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38681988

RESUMO

BACKGROUND: The prognosis for hepatocellular carcinoma (HCC) in the presence of cirrhosis is unfavourable, primarily attributable to the high incidence of recurrence. AIM: To develop a machine learning model for predicting early recurrence (ER) of post-hepatectomy HCC in patients with cirrhosis and to stratify patients' overall survival (OS) based on the predicted risk of recurrence. METHODS: In this retrospective study, 214 HCC patients with cirrhosis who underwent curative hepatectomy were examined. Radiomics feature selection was conducted using the least absolute shrinkage and selection operator and recursive feature elimination methods. Clinical-radiologic features were selected through univariate and multivariate logistic regression analyses. Five machine learning methods were used for model comparison, aiming to identify the optimal model. The model's performance was evaluated using the receiver operating characteristic curve [area under the curve (AUC)], calibration, and decision curve analysis. Additionally, the Kaplan-Meier (K-M) curve was used to evaluate the stratification effect of the model on patient OS. RESULTS: Within this study, the most effective predictive performance for ER of post-hepatectomy HCC in the background of cirrhosis was demonstrated by a model that integrated radiomics features and clinical-radiologic features. In the training cohort, this model attained an AUC of 0.844, while in the validation cohort, it achieved a value of 0.790. The K-M curves illustrated that the combined model not only facilitated risk stratification but also exhibited significant discriminatory ability concerning patients' OS. CONCLUSION: The combined model, integrating both radiomics and clinical-radiologic characteristics, exhibited excellent performance in HCC with cirrhosis. The K-M curves assessing OS revealed statistically significant differences.


Assuntos
Carcinoma Hepatocelular , Hepatectomia , Cirrose Hepática , Neoplasias Hepáticas , Aprendizado de Máquina , Recidiva Local de Neoplasia , Tomografia Computadorizada por Raios X , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Feminino , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/cirurgia , Estudos Retrospectivos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Idoso , Tomografia Computadorizada por Raios X/métodos , Prognóstico , Valor Preditivo dos Testes , Curva ROC , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Estimativa de Kaplan-Meier , Adulto , Fígado/diagnóstico por imagem , Fígado/patologia , Fígado/cirurgia , Fatores de Risco , Radiômica
3.
J Int Med Res ; 52(2): 3000605241232916, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38422024

RESUMO

Traumatic testicular dislocation is rare and usually occurs in patients after a traumatic motor accident. Manual reduction or surgical exploration is the main treatment for this condition. We report a rare case of unilateral traumatic testicular dislocation in a man with an ectopic testis in the middle of the penis after a motorcycle crash injury. On the sixth day of hospitalization, the patient found a lump in the middle of his penis. Doppler ultrasound showed an ectopic testicle in the middle of the penis with good blood flow. After consultation, a manual reduction was successfully performed. A careful physical examination should be performed in patients with multiple injuries from the first medical exam. Early detection and timely reduction are critical to protect testicular function.


Assuntos
Criptorquidismo , Luxações Articulares , Traumatismo Múltiplo , Masculino , Humanos , Pênis/diagnóstico por imagem , Pênis/cirurgia , Pelve/lesões
4.
Int J Ophthalmol ; 16(12): 1952-1961, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111929

RESUMO

AIM: To investigate the genetic and clinical characteristics of patients with a large heterozygous copy number deletion on 7q31.31-7q31.32. METHODS: A family with familial exudative vitreoretinopathy (FEVR) phenotype was included in the study. Whole-exome sequencing (WES) was initially used to locate copy number variations (CNVs) on 7q31.31-31.32, but failed to detect the precise breakpoint. The long-read sequencing, Oxford Nanopore sequencing Technology (ONT) was used to get the accurate breakpoint which is verified by quantitative real-time polymerase chain reaction (QPCR) and Sanger Sequencing. RESULTS: The proband, along with her father and younger brother, were found to have a heterozygous 4.5 Mb CNV deletion located on 7q31.31-31.32, which included the FEVR-related gene TSPAN12. The specific deletion was confirmed as del(7)(q31.31q31.32)chr7:g.119451239_123956818del. The proband exhibited a phase 2A FEVR phenotype, characterized by a falciform retinal fold, macular dragging, and peripheral neovascularization with leaking of fluorescence. These symptoms led to a significant decrease in visual acuity in both eyes. On the other hand, the affected father and younger brother showed a milder phenotype. CONCLUSION: The heterozygous CNV deletion located on 7q31.31-7q31.32 is associated with the FEVR phenotype. The use of long-read sequencing techniques is essential for accurate molecular diagnosis of genetic disorders.

5.
J Cardiovasc Dev Dis ; 10(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37887879

RESUMO

(1) Background: Epidemiological studies on the relationship between serum copper and hypertension are contradictory. We assessed the relationship between serum copper and blood pressure among adults in the United States. (2) Methods: We divided hypertension into two categories: treated hypertension and untreated hypertension. Linear or logistic regression analysis was applied to investigate the association between serum copper concentrations and blood pressure levels. (3) Results: As compared to quartile 1, the odds ratios (ORs) for untreated hypertension in quartiles 2, 3, and 4 were 1.02 (0.74-1.42), 1.23 (0.88-1.72), and 1.08 (0.74-1.58), respectively, in multivariable analysis (all p > 0.05). In non-hypertension, as compared with quartile 1, the ß (95% CI) of systolic blood pressure for quartiles 2, 3, and 4 was -0.92 (-2.07-0.23), -0.05 (-1.30-1.20), and -0.48 (-1.83-0.88), respectively, in multivariable analysis (all p > 0.05). As compared to quartile 1, the ORs for treated hypertension in quartiles 2, 3, and 4 were 1.36 (0.88-2.10), 1.35 (0.87-2.09), and 1.56 (0.98-2.47), respectively, upon multivariable analysis including antihypertensive medication use as a covariate (all p > 0.05). Furthermore, 1SD increase in serum copper was non-significantly associated with 1.16 (0.97-1.37)-fold increased risk of hypertension in multivariable analysis (p = 0.096). (4) Conclusion: In the present study, we discovered that the serum copper concentration was not related with hypertension or blood pressure levels. Antihypertensive drug use may distort the correlation between copper and blood pressure levels. Information on antihypertensive drug use may be taken into account when identifying new risk factors for hypertension.

6.
World J Gastrointest Endosc ; 15(9): 564-573, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37744321

RESUMO

BACKGROUND: We invented Endoscopic Ruler, a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension. AIM: To assess the feasibility and safety of Endoscopic Ruler, and evaluate the agreement on identifying large oesophageal varices (OV) between Endoscopic Ruler and the endoscopists, as well as the interobserver agreement on diagnosing large OV using Endoscopic Ruler. METHODS: We prospectively and consecutively enrolled patients with cirrhosis from 11 hospitals, all of whom got esophagogastroduodenoscopy (EGD) with Endoscopic Ruler. The primary study outcome was a successful measurement of the size of varices using Endoscopic Ruler. The secondary outcomes included adverse events, operation time, the agreement of identifying large OV between the objective measurement of Endoscopic Ruler and the empirical reading of endoscopists, together with the interobserver agreement on diagnosing large OV by Endoscopic Ruler. RESULTS: From November 2020 to April 2022, a total of 120 eligible patients with cirrhosis were recruited and all of them underwent EGD examinations with Endoscopic Ruler successfully without any adverse event. The median operation time of Endoscopic Ruler was 3.00 min [interquartile range (IQR): 3.00 min]. The kappa value between Endoscopic Ruler and the endoscopists while detecting large OV was 0.52, demonstrating a moderate agreement. The kappa value for diagnosing large OV using Endoscopic Ruler among the six independent observers was 0.77, demonstrating a substantial agreement. CONCLUSION: The data demonstrates that Endoscopic Ruler is feasible and safe for measuring the size of varices in patients with cirrhosis and portal hypertension. Endoscopic Ruler is potential to promote the clinical practice of the two-grade classification system of OV.

8.
ACS Nano ; 17(17): 16633-16643, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37458508

RESUMO

Bismuth oxyselenide (Bi2O2Se) is a two-dimensional (2D) layered semiconductor material with high electron Hall mobility and excellent environmental stability as well as strong spin-orbit interaction (SOI), which has attracted intense attention for application in spintronic and spin optoelectronic devices. However, a comprehensive study of spin photocurrent and its microscopic origin in Bi2O2Se is still missing. Here, the helicity-dependent photocurrent (HDPC) was investigated in Bi2O2Se nanosheets. By analyzing the dependence of HDPC on the angle of incidence, we find that the HDPC originates from surface states with Cs symmetry in Bi2O2Se, which can be attributed to the circular photogalvanic effect (CPGE) and circular photon drag effect (CPDE). It is revealed that the HDPC current almost changes linearly with the source-drain voltage. Furthermore, we demonstrate effective tuning of HDPC in Bi2O2Se by ionic liquid gating, indicating that the spin splitting of the surface electronic structure is effectively tuned. By analyzing the gate voltage dependence of HDPC, we can unambiguously identify the surface polarity and the surface electronic structure of Bi2O2Se. The large HDPC in Bi2O2Se nanosheets and its efficient electrical tuning demonstrate that 2D Bi2O2Se nanosheets may provide a good platform for opto-spintronics devices.

9.
Chinese Journal of Trauma ; (12): 299-308, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-992602

RESUMO

The acute combination fractures of the atlas and axis in adults have a higher rate of neurological injury and early death compared with atlas or axial fractures alone. Currently, the diagnosis and treatment choices of acute combination fractures of the atlas and axis in adults are controversial because of the lack of standards for implementation. Non-operative treatments have a high incidence of bone nonunion and complications, while surgeries may easily lead to the injury of the vertebral artery, spinal cord and nerve root. At present, there are no evidence-based Chinese guidelines for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults. To provide orthopedic surgeons with the most up-to-date and effective information in treating acute combination fractures of the atlas and axis in adults, the Spinal Trauma Group of Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field of spinal trauma to develop the Evidence-based guideline for clinical diagnosis and treatment of acute combination fractures of the atlas and axis in adults ( version 2023) by referring to the "Management of acute combination fractures of the atlas and axis in adults" published by American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) in 2013 and the relevant Chinese and English literatures. Ten recommendations were made concerning the radiological diagnosis, stability judgment, treatment rules, treatment options and complications based on medical evidence, aiming to provide a reference for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults.

10.
Chinese Journal of Trauma ; (12): 204-213, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-992589

RESUMO

Ankylosing spondylitis (AS) combined with spinal fractures with thoracic and lumbar fracture as the most common type shows characteristics of unstable fracture, high incidence of nerve injury, high mortality and high disability rate. The diagnosis may be missed because it is mostly caused by low-energy injury, when spinal rigidity and osteoporosis have a great impact on the accuracy of imaging examination. At the same time, the treatment choices are controversial, with no relevant specifications. Non-operative treatments can easily lead to bone nonunion, pseudoarthrosis and delayed nerve injury, while surgeries may be failed due to internal fixation failure. At present, there are no evidence-based guidelines for the diagnosis and treatment of AS combined with thoracic and lumbar fracture. In this context, the Spinal Trauma Academic Group of Orthopedics Branch of Chinese Medical Doctor Association organized experts to formulate the Clinical guideline for the diagnosis and treatment of adult ankylosing spondylitis combined with thoracolumbar fracture ( version 2023) by following the principles of evidence-based medicine and systematically review related literatures. Ten recommendations on the diagnosis, imaging evaluation, classification and treatment of AS combined with thoracic and lumbar fracture were put forward, aiming to standardize the clinical diagnosis and treatment of such disorder.

11.
J Phys Chem Lett ; 13(50): 11689-11695, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36512319

RESUMO

A spin-related photocurrent excited by circularly polarized light is observed near the electrodes on a few-layer ReS2 sample at room temperature. For both electrodes, the spatial distribution of the spin photocurrent shows a feature of two wings, with one positive and the other negative. In this work, it is suggested that this phenomenon arises from the inverse spin Hall effect due to the local electric field near the electrode. Bias voltage that modulates this field further controls the sign and magnitude of the spin photocurrent. Our research shows that the electric field near the electrodes has a significant impact on the spin transmission operation, and hence it could be taken into account for manufacturing spintronic devices in the future.

12.
Front Surg ; 9: 981025, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36003281

RESUMO

Background: Gorham-Stout syndrome is an uncommon condition with a varied clinical presentation and unclear cause that is characterised by a proliferation of lymphatic capillaries and severe regional osteolysis. Spinal and visceral involvement increases the syndrome's morbidity and mortality rates. Here, we report about a male patient with Gorham's disease who developed local kyphosis and neurological disorders due to massive osteolysis. Case presentation: A 13-year-old male patient presented with progressive kyphosis and massive osteolysis of the thoracic vertebrae. Halo-pelvic traction and vertebral column resection osteotomy were performed to reconstruct the spine and prevent disease progression. The entire lesion was resected, and an artificial vertebra filled with allograft bone was used to achieve temporary stability. Although the patient presented with chylothorax following surgery, which required thoracic drainage, the patient did achieve a satisfying outcome. Conclusions: Limited by the number of GSS cases with spinal involvement and chylothorax manifestations, halo-pelvic distraction as a preoperative preparation and vertebral column resection osteotomy provide a novel avenue for managing this disease.

13.
J Nerv Ment Dis ; 210(10): 754-759, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35849536

RESUMO

ABSTRACT: Virtual reality therapy (VRT) is a new psychotherapeutic approach integrating virtual reality technology and psychotherapy. This case series aimed to study effectiveness of VRT in treating psychological problems. We described four cases of first-line health care professionals with emerging clinically significant early psychological problems during the COVID-19 outbreak, and specifically received the VRT treatment. We compared the Patient Health Questionnaire 9 items (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), PHQ-15, and Athens Insomnia Scale to evaluate psychological symptoms and sleep quality before and after sessions. All four cases showed a reduction in scale comparison. General scores of the PHQ-9 reduced 65%, GAD-7 reduced 52.17%, PHQ-15 decreased 38.17%, and scores of the Athens Insomnia Scale reduced 67.44%. Meanwhile, a reduction in depression, anxiety, psychosomatic, and sleeping symptoms was also found, which decreased 76.92% in general. These results are highly significant statistically. This case series demonstrated the effectiveness of VRT on psychological problems as a promising approach to apply on various psychological distress and disorders.


Assuntos
COVID-19 , Distúrbios do Início e da Manutenção do Sono , Realidade Virtual , Ansiedade/psicologia , Depressão/psicologia , Pessoal de Saúde/psicologia , Humanos , Pandemias , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/terapia
14.
Front Med (Lausanne) ; 9: 854788, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646985

RESUMO

Objective: The long-term impact of COVID-19 on patient health has been a recent focus. This study aims to determine the persistent symptoms and psychological conditions of patients hospitalized with COVID-19 15 months after onset, that patients first developed symptoms. The potential risk factors were also explored. Methods: A cohort of COVID-19 patients discharged from February 20, 2020 to March 31, 2020 was recruited. Follow-ups were conducted using validated questionnaires and psychological screening scales at 15 months after onset to evaluate the patients' health status. The risk factors for long-term health impacts and their associations with disease severity was analyzed. Findings: 534 COVID-19 patients were enrolled. The median age of the patients was 62.0 years old (IQR 52.0-70.0) and 295 were female (55.2%). The median time from onset to follow-up was 460.0 (451.0-467.0) days. Sleep disturbance (18.5%, 99/534) and fatigue (17.2%, 92/534) were the most common persistent symptoms. 6.4% (34/534) of the patients had depression, 9.2% (49/534) were anxious, 13.0% (70/534) had insomnia and 4.7% (25/534) suffered from post-traumatic stress disorder (PTSD). Multivariate adjusted logistic regression analysis showed that glucocorticoid use during hospitalization (OR 3.58, 95% CI 1.12-11.44) was significantly associated with an increased risk of fatigue. The OR values for anxiety and sleep disorders were 2.36 (95% CI 1.07-5.20) and 2.16 (95% CI 1.13-4.14) in females to males. The OR value of PTSD was 25.6 (95% CI 3.3-198.4) in patients with persistent symptoms to those without persistent symptoms. No significant associations were observed between fatigue syndrome or adverse mental outcomes and disease severity. Conclusions: 15-month follow-up in this study demonstrated the need of extended rehabilitation intervention for complete recovery in COVID-19 patients.

15.
Opt Express ; 30(7): 11684-11692, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473107

RESUMO

Quantum interference plays an essential role in understanding the concepts of quantum physics. Moreover, the interference of photons is indispensable for large-scale quantum information processing. With the development of quantum networks, interference of photons transmitted through long-distance fiber channels has been widely implemented. However, quantum interference of photons using free-space channels is still scarce, mainly due to atmospheric turbulence. Here, we report an experimental demonstration of Hong-Ou-Mandel interference with photons transmitted by free-space channels. Two typical photon sources, i.e., correlated photon pairs generated in spontaneous parametric down conversion (SPDC) process and weak coherent states, are employed. A visibility of 0.744 ± 0.013 is observed by interfering with two photons generated in the SPDC process, exceeding the classical limit of 0.5. Our results demonstrate that the quantum property of photons remains even after transmission through unstable free-space channels, indicating the feasibility and potential application of free-space-based quantum interference in quantum information processing.

16.
Opt Express ; 30(2): 2089-2096, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209356

RESUMO

Electrically generated spin accumulation due to the spin Hall effect of Pt/GaAs is detected by circular polarized photoconductivity (CPPC), which shows electron spins with different polarizations accumulated around opposite sample boundaries. An optical absorption model incorporating spin is used to explain these features. The detailed analysis of the observed degree of circular polarization of the photocurrent strongly suggests that Pt and GaAs have the same spin accumulation length in the Pt/GaAs heterostructure.

17.
Arab J Gastroenterol ; 23(2): 82-88, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35120839

RESUMO

BACKGROUND AND STUDY AIMS: Post-hepatectomy liver failure (PHLF) is the main cause of perioperative death after hepatocellular carcinoma (HCC) resection. PHLF occurrence is related to both the hepatectomy volume and the degree of cirrhosis. Accurate preoperative assessment of the degree of cirrhosis may aid in reducing the incidence of PHLF. Several studies have shown that the liver stiffness measurement (LSM) is well correlated with cirrhosis. This study explored the relationship between LSM and PHLF occurrence after radical HCC resection and the effect on long-term prognosis. PATIENTS AND METHODS: We retrospectively analyzed the clinical data of 164 patients who underwent radical HCC resection at our center from January 2017 to January 2020. The related postoperative PHLF factors were analyzed. The LSM threshold in postoperative PHLF was calculated through receiver operating characteristic (ROC) curve analysis. Patients were grouped according to different LSM thresholds and survival analysis was performed. RESULTS: Forty-six patients experienced PHLF, of whom 19, 21, and 6 were classified as grades A, B, and C, respectively. Multivariate analysis indicated that LSM was an independent risk factor for PHLF after HCC surgery (OR = 1.174, P < 0.000). LSM (OR = 1.219, P < 0.000) and intraoperative bleeding (OR = 1.001, P = 0.047) were risk factors for grade B-C PHLF. The LSM threshold that predicted PHLF occurrence was 17.9 kPa (AUC = 0.831, P < 0.000) and 24.5 kPa (AUC = 0.867, P < 0.000) for grade B-C PHLF. LSM was correlated with PHLF severity (r = 0.439, P < 0.001). The median survival times were 32 vs 26 months (P = 0.016) for patients with LSM ≤ 17.9 kPa vs those with LSM > 17.9 kPa and 28 vs 24 months (P = 0.004) for patients with LSM ≤ 24.5 kPa vs those with LSM > 24.5 kPa. CONCLUSION: LSM is related to PHLF occurrence in patients undergoing HCC resection; a higher LSM is associated with the occurrence of more severe PHLF after surgery. In addition, LSM may aid in predicting long-term survival after liver resection in patients with HCC.


Assuntos
Carcinoma Hepatocelular , Falência Hepática , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Humanos , Cirrose Hepática/patologia , Falência Hepática/etiologia , Neoplasias Hepáticas/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Retrospectivos
18.
Sensors (Basel) ; 22(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35009939

RESUMO

Circularly polarized photocurrent, observed in p-doped bulk GaAs, varies nonlinearly with the applied bias voltage at room temperature. It has been explored that this phenomenon arises from the current-induced spin polarization in GaAs. In addition, we found that the current-induced spin polarization direction of p-doped bulk GaAs grown in the (001) direction lies in the sample plane and is perpendicular to the applied electric field, which is the same as that in GaAs quantum well. This research indicates that circularly polarized photocurrent is a new optical approach to investigate the current-induced spin polarization at room temperature.

19.
Injury ; 53(4): 1361-1367, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35082056

RESUMO

BACKGROUND: Osteonecrosis of femoral head (ONFH) is a pathological state caused by lack of blood supply in femoral head. This study aimed to explore the function of Lycium barbarum polysaccharide (LBP), an antioxidant agent extracted from L. barbarum, on ONFH. METHODS: Osteonecrosis rat model was generated using lipopolysaccharide (LPS) and methylprednisolone followed by examination of body weight, blood glucose, morphology, and BMSC osteoblast differentiation. The effect and underlying mechanism of LBP on the proliferation, apoptosis, and osteoblast differentiation of BMSC were determined with or without LPS or hypoxia treatment using CCK-8. Alizarin Red S staining, flow cytometry, and western blot, respectively. RESULT: LBP could protect against glucocorticoid-induced ONFH in rats, resulting in improved sparse trabecular bone, empty lacunae and bone cell coagulation. Moreover, LBP promoted the proliferation and osteoblast differentiation of bone mesenchymal-derived stem cells (BMSCs) in a dose-dependent manner. Furthermore, LBP enhanced osteoblast differentiation of BMSCs under hypoxia condition. Mechanistically, we found that LBP treatment enhanced Runx2 and ALP expression in BMSCs. LBP restored the expression of Runx2 and ALP under hypoxia, suggesting that LBP might be involved in regulating Runx2/ALP expression and contributed to osteoblast differentiation. Knockdown of Runx2 significantly inhibited BMSCs proliferation, while LBP treatment did not rescue the osteoblast differentiation ability of BMSCs with Runx2 knockdown. CONCLUSION: Our findings suggested that LBP protects against ONFH via regulating Runx2 expression, which could be utilized to treat patients suffering ONFH.


Assuntos
Medicamentos de Ervas Chinesas , Necrose da Cabeça do Fêmur , Animais , Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core , Medicamentos de Ervas Chinesas/efeitos adversos , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/prevenção & controle , Humanos , Osteogênese , Ratos
20.
Huan Jing Ke Xue ; 43(2): 663-674, 2022 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-35075840

RESUMO

The PM2.5 forecast models of 95 cities in Beijing-Tianjin-Hebei and its surrounding cities (BTH); the Fenwei Plain (FWP); the border area of Jiangsu, Anhui, Shandong, and Henan (JASH); and the Yangtze River Delta (YRD) regions were established using BP neural network models, and the forecast was carried out for the next seven days in the autumn and winter in 2020. By comparing the forecast results of the BP neural network models, numerical model, and artificial correction, the PM2.5 forecast effects of the three methods were analyzed and evaluated. The results showed:① The performance of the short-term forecast based on the BP neural network was relatively good but was reduced in the medium and long term and systematically overestimated in four regions. The numerical model effects were lower than those of the BP neural network models. ② The accuracy rates of the PM2.5 forecast concentration by the three methods were generally low in the four regions, with an average of less than 50%, and the accuracy values in order from high to low were the BP neural network models, artificial correction, and the numerical model. The accuracy rates of IAQI levels of PM2.5 were significantly improved by the three methods, and the averages were above 65% in the first four days. The effects of the BP neural network models and artificial correction were similar, which were generally higher than those of the numerical model. ③ The numerical model had good effects in the BTH, JASH, and YRD regions, whereas it was the worst when forecasting moderately and above-polluted days in the FWP region. The BP neural network model had a good performance when forecasting short-term PM2.5 in the BTH, JASH, and FWP regions, whereas it was poor in the YRD region. In general, the performance of artificial correction was relatively good when forecasting moderate-level days and was close to the BP neural network model when forecasting heavily polluted days.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Redes Neurais de Computação , Material Particulado/análise
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