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1.
Nature ; 616(7955): 96-103, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36813965

RESUMO

Rapid demographic ageing substantially affects socioeconomic development1-4 and presents considerable challenges for food security and agricultural sustainability5-8, which have so far not been well understood. Here, by using data from more than 15,000 rural households with crops but no livestock across China, we show that rural population ageing reduced farm size by 4% through transferring cropland ownership and land abandonment (approximately 4 million hectares) in 2019, taking the population age structure in 1990 as a benchmark. These changes led to a reduction of agricultural inputs, including chemical fertilizers, manure and machinery, which decreased agricultural output and labour productivity by 5% and 4%, respectively, further lowering farmers' income by 15%. Meanwhile, fertilizer loss increased by 3%, resulting in higher pollutant emissions to the environment. In new farming models, such as cooperative farming, farms tend to be larger and operated by younger farmers, who have a higher average education level, hence improving agricultural management. By encouraging the transition to new farming models, the negative consequences of ageing can be reversed. Agricultural input, farm size and farmer's income would grow by approximately 14%, 20% and 26%, respectively, and fertilizer loss would reduce by 4% in 2100 compared with that in 2020. This suggests that management of rural ageing will contribute to a comprehensive transformation of smallholder farming to sustainable agriculture in China.


Assuntos
Distribuição por Idade , Agricultura , Fazendeiros , Fazendas , Segurança Alimentar , População Rural , Desenvolvimento Sustentável , Humanos , Agricultura/economia , Agricultura/educação , Agricultura/métodos , Agricultura/organização & administração , China , Fazendeiros/educação , Fazendeiros/estatística & dados numéricos , Fazendas/economia , Fazendas/organização & administração , Fazendas/estatística & dados numéricos , Fazendas/tendências , Fertilizantes/análise , Fatores Etários , Segurança Alimentar/economia , Segurança Alimentar/métodos , Desenvolvimento Sustentável/economia , Desenvolvimento Sustentável/tendências , População Rural/estatística & dados numéricos , População Rural/tendências , Eficiência , Poluentes Ambientais
2.
Opt Express ; 32(5): 8129-8145, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439478

RESUMO

Photocathodes play a crucial role in photoelectronic imaging and vacuum electronic devices. The quantum efficiency of photocathodes, which determines their performance, can be enhanced through materials engineering. However, the quantum efficiency of conventional planar photocathodes remains consistently low, at around 25%. In this paper, we propose what we believe is a novel structure of AlGaN nanowire array to address this issue. We investigate the photoemission characteristics of the nanowire array using the "four-step" process, which takes into account optical absorption, electron transportation, electron emission, and electron collection. We compare the quantum efficiency of nanowire arrays with different structure sizes and Al components. After studying the effect of incident light at various angles on the nanowire array photocathode, we identify the optimal dimensional parameters: a height of 400∼500 nm and a wire width of 200∼300 nm. Furthermore, we improved the collection efficiency of the photocathode by introducing a built-in/external electric field, and obtained a 104.4% enhancement of the collection current with the built-in electric field, meanwhile the photocurrent was increased by 87% compared to the case without the external electric field. These findings demonstrate the potential of optimizing photocathode performance through the development of a novel model and adjustment of parameters, offering a promising approach for photocathode applications.

3.
J Anesth ; 38(3): 377-385, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38441686

RESUMO

PURPOSE: More literature studies have reported that alfentanil is safe and effective for labor analgesia. However, there is no unified consensus on the optimal dosage of alfentanil used for epidural analgesia. This study explored the concentration at 90% of minimum effective concentration (EC90) of alfentanil combined with 0.075% ropivacaine in patients undergoing epidural labor analgesia to infer reasonable drug compatibility and provide guidance for clinical practice. METHODS: In this prospective, single-center, double-blind study, a total of 45 singleton term primiparas with vaginal delivery who volunteered for epidural labor analgesia were recruited. The first maternal was administered with 3 µg/mL alfentanil combined with 0.075% ropivacaine with the infusion of 10 mL of the mixture every 50 min at a background dose of 3 mL/h. In the absence of PCEA, a total of 15 mL of the mixture is injected per hour. The subsequent alfentanil concentration was determined on the block efficacy of the previous case, using an up-down sequential allocation with a bias-coin design. 30 min after epidural labor analgesia, the block of patient failed with visual analog score (VAS) > 3, the alfentanil concentration was increased in a 0.5 µg/mL gradient for the next patient, while the block was successful with VAS ≤ 3, the alfentanil concentration was remained or decreased in a gradient according to a randomized response list for the next patient. EC90 and 95% confidence interval were calculated by linear interpolation and prediction model with R statistical software. RESULTS: In this study, the estimated EC90 of alfentanil was 3.85 µg/mL (95% confidence interval, 3.64-4.28 µg/mL). CONCLUSION: When combined with ropivacaine 0.075%, the EC90 of alfentanil for epidural labor analgesia is 3.85 µg/mL in patients undergoing labor analgesia.


Assuntos
Alfentanil , Analgesia Epidural , Analgesia Obstétrica , Analgésicos Opioides , Anestésicos Locais , Ropivacaina , Humanos , Ropivacaina/administração & dosagem , Feminino , Método Duplo-Cego , Alfentanil/administração & dosagem , Gravidez , Analgesia Epidural/métodos , Estudos Prospectivos , Adulto , Anestésicos Locais/administração & dosagem , Analgesia Obstétrica/métodos , Analgésicos Opioides/administração & dosagem , Relação Dose-Resposta a Droga , Medição da Dor/métodos , Medição da Dor/efeitos dos fármacos
4.
Exp Cell Res ; 414(1): 113095, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35259401

RESUMO

Kinesin-14 KIFC1 regulates spindle assembly and centrosome clustering in diverse organisms during cell division. KIFC1 proteins are essential for spindle assembly and chromosome alignment in mitosis. However, the roles and mechanisms of KIFC1 proteins in male spermatocytes remain largely unknown. In this study, we reveal that KIFC1 proteins mainly accumulate at the centrosomes and central spindle in mouse spermatocytes both in vitro and in vivo. We utilize two KIFC1 specific inhibitors, AZ82 and CW069, for the inhibition of KIFC1 in mouse spermatogenic cells and cultured GC-2 spd(ts) cells. We find that KIFC1 inhibition results in the increase of spermatocytes with micronuclei, the disorganization of the meiotic spindles, and the formation of multiple centrosomes. Furthermore, we demonstrate that KIFC1 inhibition leads to spindle defects, chromosome misalignment and the formation of aneuploidy in cultured GC-2 spd(ts) cells. In this study, we reveal that KIFC1 proteins are critical for centrosome maintenance and chromosome stability in mouse spermatocytes.


Assuntos
Segregação de Cromossomos , Cinesinas , beta Carioferinas/metabolismo , Animais , Centrossomo/metabolismo , Cinesinas/genética , Masculino , Meiose , Camundongos , Mitose , Espermatócitos , Fuso Acromático/metabolismo
5.
Sensors (Basel) ; 23(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38139625

RESUMO

As technologies like the Internet, artificial intelligence, and big data evolve at a rapid pace, computer architecture is transitioning from compute-intensive to memory-intensive. However, traditional von Neumann architectures encounter bottlenecks in addressing modern computational challenges. The emulation of the behaviors of a synapse at the device level by ionic/electronic devices has shown promising potential in future neural-inspired and compact artificial intelligence systems. To address these issues, this review thoroughly investigates the recent progress in metal-oxide heterostructures for neuromorphic applications. These heterostructures not only offer low power consumption and high stability but also possess optimized electrical characteristics via interface engineering. The paper first outlines various synthesis methods for metal oxides and then summarizes the neuromorphic devices using these materials and their heterostructures. More importantly, we review the emerging multifunctional applications, including neuromorphic vision, touch, and pain systems. Finally, we summarize the future prospects of neuromorphic devices with metal-oxide heterostructures and list the current challenges while offering potential solutions. This review provides insights into the design and construction of metal-oxide devices and their applications for neuromorphic systems.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(11): 1150-1155, 2023 Nov 15.
Artigo em Zh | MEDLINE | ID: mdl-37990460

RESUMO

OBJECTIVES: To investigate the expression and significance of jumonji domain-containing protein 2B (JMJD2B) and hypoxia-inducible factor-1α (HIF-1α) in non-Hodgkin's lymphoma (NHL) tissues in children. METHODS: Immunohistochemistry was used to detect the expression of JMJD2B and HIF-1α in lymph node tissue specimens from 46 children with NHL (observation group) and 24 children with reactive hyperplasia (control group). The relationship between JMJD2B and HIF-1α expression with clinicopathological characteristics and prognosis in children with NHL, as well as the correlation between JMJD2B and HIF-1α expression in NHL tissues, were analyzed. RESULTS: The positive expression rates of JMJD2B (87% vs 21%) and HIF-1α (83% vs 42%) in the observation group were higher than those in the control group (P<0.05). The expression of JMJD2B and HIF-1α was correlated with serum lactate dehydrogenase levels and the risk of international prognostic index in children with NHL (P<0.05). The expression of JMJD2B was positively correlated with the HIF-1α expression in children with NHL (rs=0.333, P=0.024). CONCLUSIONS: JMJD2B and HIF-1α are upregulated in children with NHL, and they may play a synergistic role in the development of pediatric NHL. JMJD2B can serve as a novel indicator for auxiliary diagnosis, evaluation of the severity, treatment guidance, and prognosis assessment in pediatric NHL.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Linfoma não Hodgkin , Humanos , Criança , Prognóstico , Hipóxia
7.
Nanotechnology ; 32(38)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34102620

RESUMO

Ultraviolet photodetector has a variety of applications in medical diagnosis, civilian testing and military security. The enhancement of photo response has far been a hot topic regrading to the performance improvement of the devices. In this study, we proposed a self-powered photodetector based on AlxGa1-xN nanowire arrays (NWAs) utilizing axial pn junction integrating with gradient Al component. The merit of the coupling structure is demonstrated by theoretical model and simulations. The photoelectric conversion model is built based on a continuity equation derived by its corresponding boundary conditions. The photocurrent for a single nanowire and NWAs are respectively obtained. According to the simulation results of a single nanowire, the optimal nanowire height is obtained with a photocurrent enhancement up to 330%. For NWAs, the aspect ratio of NWAs and incident angle of light synergistically determine the output photocurrent. The optimal aspect ratio for NWAs is 1:1 with an optimal incident angle of 57°. This study provides a reliable method for the design of photodetectors with micro-nano structures.

8.
Nanotechnology ; 31(2): 025201, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31539893

RESUMO

GaN has interesting prospects in applications for spectrum-tunable solid-state devices with photoelectric conversion function. Similarly, single nanowires or nanowire arrays (NWAs) proceed to exhibit good photon absorbance and photoemission characteristics as vacuum devices based on the external photoelectric effect. However, the collection of photoelectrons emitted from a nanowire surface has become the greatest impediment to the progress of GaN NWAs photocathodes. In this study, a field-assisted GaN NWA photocathode is proposed. The photoemission efficiency and electron collection efficiency of the field-assisted GaN NWA photocathode are derived. The results suggest that the external field can effectively enhance the photoemission capacity and electron collection efficiency of the photocathode. Based on the theoretical model, the structural parameters of NWAs and the field intensity are optimized. When the field intensity is 1 V µm-1, the collected photocurrent of the GaN NWA photocathode reaches a maximum. For NWAs with an aspect ratio of 1:1, the optimal incident angle of light is 70°. This study provides a theoretical guide for the incorporation of an external field in a GaN NWA photocathode with the purpose of enhancing photoemission and electron collection capacity.

9.
J Clin Lab Anal ; 34(11): e23463, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32648293

RESUMO

BACKGROUND: The extracellular calcium-sensing receptor (CASR) controls body calcium homeostasis. Increased levels of calcium are associated with protecting against colorectal cancer (CRC). This study aimed to determine the relationship between CASR gene rs1801725 polymorphism and CRC risk and prognosis. METHODS: We conducted a hospital-based case-control study and a meta-analysis to evaluate the association of CASR gene rs1801725 polymorphism with CRC susceptibility. RESULTS: This study proved that CASR rs1801725 polymorphism was associated with a higher risk to develop CRC (TT vs GG: OR 1.92, 95% CI [1.03-3.59], P = .042; T vs G: OR 1.30, 95% CI [1.03-1.64], P = .030). Subgroup analysis showed that this polymorphism increased the risk of CRC among smokers, and those aged ≥60 years (TT vs GG: OR 3.37, 95% CI [1.12-10.14], P = .034). We also found that this polymorphism was associated with the tumor size, TNM stage, and lymph node metastasis of CRC (GT vs GG: OR 2.03, 95% CI [1.32-3.10], P = .001). In addition, CASR gene rs1801725 polymorphism correlated with the survival of CRC patients. Further meta-analysis also obtained a significant association between this SNP and CRC risk (TT + GT vs GG: OR 1.28, 95% CI [1.01, 1.63], P = .041). Subgroup analyses by ethnicity observed a link between rs1801725 polymorphism and CRC risk in Asians, but not in Caucasians and mixed populations. CONCLUSION: In conclusion, this case-control study and meta-analysis showed that CASR rs1801725 polymorphism increased the risk of CRC. Further studies from other races are urgently needed.


Assuntos
Neoplasias Colorretais , Predisposição Genética para Doença/genética , Receptores de Detecção de Cálcio/genética , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
10.
Proc Natl Acad Sci U S A ; 114(23): E4631-E4640, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28533408

RESUMO

Like many complex human diseases, esophageal squamous cell carcinoma (ESCC) is known to cluster in families. Familial ESCC cases often show early onset and worse prognosis than the sporadic cases. However, the molecular genetic basis underlying the development of familial ESCC is mostly unknown. We reported that SLC22A3 is significantly down-regulated in nontumor esophageal tissues from patients with familial ESCC compared with tissues from patients with sporadic ESCCs. A-to-I RNA editing of the SLC22A3 gene results in its reduced expression in the nontumor esophageal tissues of familial ESCCs and is significantly correlated with lymph node metastasis. The RNA-editing enzyme ADAR2, a familial ESCC susceptibility gene identified by our post hoc genome-wide association study, is positively correlated with the editing level of SLC22A3 Moreover, functional studies showed that SLC22A3 is a metastasis suppressor in ESCC, and deregulation of SLC22A3 facilitates cell invasion and filopodia formation by reducing its direct association with α-actinin-4 (ACTN4), leading to the increased actin-binding activity of ACTN4 in normal esophageal cells. Collectively, we now show that A-to-I RNA editing of SLC22A3 contributes to the early development and progression of familial esophageal cancer in high-risk individuals.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Edição de RNA , Actinina/metabolismo , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Adulto , Idoso , Animais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular , Progressão da Doença , Regulação para Baixo , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/secundário , Carcinoma de Células Escamosas do Esôfago , Esôfago/citologia , Esôfago/metabolismo , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla , Humanos , Metástase Linfática/genética , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Proteínas de Transporte de Cátions Orgânicos/deficiência , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Risco
11.
J Cell Physiol ; 234(8): 12714-12726, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30523632

RESUMO

KCNQ/M potassium channels play a vital role in neuronal excitability; however, it is required to explore their pharmacological modulation on N-Methyl- d-aspartic acid receptors (NMDARs)-mediated glutamatergic transmission of neurons upon ischemic insults. In the current study, both presynaptic glutamatergic release and activities of NMDARs were measured by NMDAR-induced miniature excitatory postsynaptic currents (mEPSCs) in cultured cortical neurons of C57 mice undergoing oxygen and glucose deprivation (OGD) or OGD/reperfusion (OGD/R). The KCNQ/M-channel opener, retigabine (RTG), suppressed the overactivation of postsynaptic NMDARs induced by OGD and then NO transient; RTG also decreased OGD-induced neuronal death measured with MTT assay, suggesting the beneficial role of KCNQ/M-channels for the neurons exposed to ischemic insults. However, when the neurons exposed to the subsequent reperfusion, KCNQ/M-channels played a differential role from its protective effect. OGD/R increased presynaptic glutamatergic release, which was further augmented by RTG or decreased by KCNQ/M-channel blocker, XE991. Reactive oxygen species (ROS) were produced partly in a NO-dependent manner. In addition, XE991 decreased neuronal injuries upon reperfusion measured with DCF and PI staining. Meanwhile, the addition of RTG upon OGD or XE991 upon reperfusion can reverse OGD or OGD/R-reduced mitochondrial membrane potential. Our present study indicates the dual role of KCNQ/M-channels in OGD and OGD/R, which will decide the fate of neurons. Provided that activation of KCNQ/M-channels has differential effects on neuronal injuries during OGD or OGD/R, we propose that therapy targeting KCNQ/M-channels may be effective for ischemic injuries but the proper timing is so crucial for the corresponding treatment.


Assuntos
Glucose/metabolismo , Canais de Potássio KCNQ/metabolismo , Neurônios/metabolismo , Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Carbamatos/farmacologia , Feminino , Ácido Glutâmico/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Fenilenodiaminas/farmacologia
12.
J Nanosci Nanotechnol ; 18(6): 4397-4402, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442794

RESUMO

In this work, we demonstrate the feasibility of preparing Au/TiO2 nanorods via a dc magnetron sputtering at room temperature and heat-treatment at 500 °C in air for 2 h. The heat treatment leads to the migration of Au atoms into TiO2 nanofilm to form Au/TiO2 nanorods with Au nanoparticles embedded in the TiO2 nanorods of anatase phase. The Au nanoparticles in the TiO2 nanorods suppress the charge recombination. These Au/TiO2 nanorods showed high absorption and intensive response to the visible light and had improved photocatalytic properties in comparison with pure TiO2 nanoparticles formed by using similar method.

13.
J Asian Nat Prod Res ; 18(9): 897-907, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27256478

RESUMO

A water-soluble polysaccharide (named RAP) was newly isolated from the stems of Rubus amabilis. Structural confirmation of the polysaccharide was provided by hydrolysis, periodate oxidation, Smith degradation, and methylation analysis, combined with nuclear magnetic resonance (NMR), capillary electrophoresis (CE), infrared spectroscopy (IR), and gas chromatography-mass spectra (GC-MS). In vitro immunological enhancement activity was characterized using the proliferative activity of spleen lymphocytes and phagocytic activity of peritoneal macrophages in mice. The polysaccharide was mainly composed of xylose, arabinose, glucose, rhamnose, galactose, mannose, glucuronic acid, and galactocuronic acid in the molar ratio of 1.0:6.9:0.8:1.1:6.9:0.3:0.5:3.3, with the average molecular weight of 26.2 kDa. The linkage types of netural monosaccharides were as follows: the arabinose was →2) Ara (1→ and galactose were Gal (1→, →3) Gal (1→, →3,6) Gal (1→, →2,3,6) Gal (1→ and →2,3,6) Galf (1→. Xyl (1→, →6) Glc (1→, →2) Glc (1→, →3) Rha (1→, Rha (1→ and Man (1→ were also found in the structure. RAP-B-2 could improve the proliferative activity of spleen T cells and B cells and boost phagocytic activity of peritoneal macrophages at the concentration of 50 µg/ml (p < 0.05, p < 0.01).


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Rubus/química , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Galactose , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Manose , Camundongos , Estrutura Molecular , Peso Molecular , Ressonância Magnética Nuclear Biomolecular , Oxirredução , Ácido Periódico , Caules de Planta/química , Polissacarídeos/química
14.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(2): 118-21, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25760833

RESUMO

OBJECTIVE: To study the changes and significance of plasma cardiotrophin-1 (CT-1) in neonates with hypoxic-ischemic encephalopathy (HIE) complicated by myocardial ischemic injury. METHODS: Forty-five neonates with HIE (15 mild cases, 24 moderate cases and 6 severe cases) were enrolled and divided into two subgroups based on the presence of myocardial injury (n=19) and not (n=26). Twenty healthy neonates were used as the control group. Plasma CT-1 levels were measured using double-antibody sandwich enzyme immunoassay method. Serum creatinine kinase MB (CK-MB) and cardiac troponin I (CTnI ) levels were also measured. RESULTS: Plasma CT-1 levels in the mild HIE (169±20 pg/mL) and moderate/severe HIE subgroups (287±44 pg/mL) were significantly higher than those in the control group (30±8 pg/mL), and plasma CT-1 levels were associated with the severity of HIE (P<0.01). Plasma CT-1 levels were positively correlated with serum CK-MB and CTnI levels in neonates with HIE in the acute phase (r=0.565 and 0.621 respectively; P<0.01). Plasma CT-1 levels in neonates with myocardial injury were significantly higher than those without myocardial injury (249 ±35 pg/mL vs 177±26 pg/mL; P<0.01). Plasma CT-1 levels were significantly reduced in neonates with myocardial injury in the convalescent phase (157±19 pg/mL) compared with those in the acute phase (249±35 pg/mL; P<0.01). CONCLUSIONS: Detection of plasma CT-1 levels may be useful in the diagnosis of myocardial ischemic injury and the severity evaluation of HIE.


Assuntos
Citocinas/sangue , Isquemia Miocárdica/sangue , Creatina Quinase Forma MB/sangue , Feminino , Humanos , Recém-Nascido , Masculino , Troponina I/sangue
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(6): 619-23, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-24927439

RESUMO

OBJECTIVE: To investigate the methylation status of zonula occludens-1 (ZO-1) gene promoter and its clinical significance in children with stage IV non-Hodgkin lymphoma (NHL) and to provide a basis for further etiological study and early diagnosis of this disease. METHODS: Fifty-five children with a confirmed diagnosis of stage IV NHL (40 cases of T-NHL and 15 cases of B-NHL) were selected as the case group, and 20 children with diseases other than hematologic malignancies were selected as the control group. Bone marrow samples were collected from these subjects. Methylation-specific PCR (MS-PCR) was applied to evaluate the methylation status of ZO-1 gene promoter, and the integrated optical density (IOD) was determined. RT-PCR was used to measure the mRNA expression of ZO-1. RESULTS: MS-PCR showed that the methylated bands of ZO-1 gene promoter were found in 39 (70.9%) of 55 patients in the case group before treatment, while no ZO-1 gene promoter methylation was detected in the control group. With close tracking of 47 cases in the study group, consisting of 32 cases of T-NHL and 15 cases of B-NHL, the rates of ZO-1 gene promoter methylation prior to treatment were 72% and 67%, respectively, (P>0.572). The cases of T-NHL and B-NHL showed no significant changes in methylation rate in the early and middle phases of chemotherapy (P>0.05), but they showed significant changes in methylation rate in the late phase of chemotherapy (P<0.05). RT-PCR showed that the NHL cases carrying methylated ZO-1 gene had no mRNA expression of ZO-1, while all children in the control group had mRNA expression of ZO-1. There was no linear relationship between the total number of peripheral blood leukocytes and ZO-1 gene IOD (r=0.093, P=0.575); a positive correlation was found between the number of malignant cells in bone marrow and ZO-1 gene IOD (r=0.669, P<0.001). CONCLUSIONS: ZO-1 gene shows a hypermethylation status in children with NHL, and the methylation level is positively correlated with the number of malignant cells in bone marrow. ZO-1 may be used as a novel molecular marker in early diagnosis, outcome assessment, prognostic evaluation, and detection of minimal residual disease.


Assuntos
Metilação de DNA , Linfoma não Hodgkin/genética , Proteína da Zônula de Oclusão-1/genética , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Regiões Promotoras Genéticas
16.
Artigo em Inglês | MEDLINE | ID: mdl-38471785

RESUMO

BACKGROUND AND PURPOSE: The efficacy of long-term chronic subthalamic nucleus deep brain stimulation (STN-DBS) in treating Parkinson disease (PD) exhibits substantial variability among individuals. The preoperative identification of suitable deep brain stimulation (DBS) candidates through predictive means becomes crucial. Our study aims to investigate the predictive value of characterizing individualized structural covariance networks for long-term efficacy of DBS, offering patients a precise and cost-effective preoperative screening tool. MATERIALS AND METHODS: We included 138 patients with PD and 40 healthy controls. We developed individualized structural covariance networks from T1-weighted images utilizing network template perturbation, and computed the networks' topological characteristics. Patients were categorized according to their long-term motor improvement following STN-DBS. Intergroup analyses were conducted on individual network edges and topological indices, alongside correlation analyses with long-term outcomes for the entire patient cohort. Finally, machine learning algorithms were employed for regression and classification to predict post-DBS motor improvement. RESULTS: Among the patients with PD, 6 edges (left middle frontal and left caudate nucleus, right olfactory and right insula, left superior medial frontal gyrus and right insula, right middle frontal and left paracentral lobule, right middle frontal and cerebellum, left lobule VIIb of the cerebellum and the vermis of the cerebellum) exhibited significant results in intergroup comparisons and correlation analyses. Increased degree centrality and local efficiency of the cerebellum, parahippocampal gyrus, and postcentral gyrus were associated with DBS improvement. A regression model constructed from these 6 edges revealed a significant correlation between predicted and observed changes in the unified PD rating scale (R = 0.671, P < .001) and receiver operating characteristic analysis demonstrated an area under the curve of 0.802, effectively distinguishing between patients with good and moderate improvement post-DBS. CONCLUSIONS: Our findings reveal the link between individual structural covariance network fingerprints in patients with PD and long-term motor outcome following STN-DBS. Additionally, binary and continuous cerebellum-basal ganglia-frontal structural covariance network edges have emerged as potential predictive biomarkers for DBS motor outcome.

17.
NPJ Parkinsons Dis ; 10(1): 115, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866758

RESUMO

Approximately 90% of Parkinson's patients (PD) suffer from dysarthria. However, there is currently a lack of research on acoustic measurements and speech impairment patterns among Mandarin-speaking individuals with PD. This study aims to assess the diagnosis and disease monitoring possibility in Mandarin-speaking PD patients through the recommended speech paradigm for non-tonal languages, and to explore the anatomical and functional substrates. We examined total of 160 native Mandarin-speaking Chinese participants consisting of 80 PD patients, 40 healthy controls (HC), and 40 MRI controls. We screened the optimal acoustic metric combination for PD diagnosis. Finally, we used the objective metrics to predict the patient's motor status using the Naïve Bayes model and analyzed the correlations between cortical thickness, subcortical volumes, functional connectivity, and network properties. Comprehensive acoustic screening based on prosodic, articulation, and phonation abnormalities allows differentiation between HC and PD with an area under the curve of 0.931. Patients with slowed reading exhibited atrophy of the fusiform gyrus (FDR p = 0.010, R = 0.391), reduced functional connectivity between the fusiform gyrus and motor cortex, and increased nodal local efficiency (NLE) and nodal efficiency (NE) in bilateral pallidum. Patients with prolonged pauses demonstrated atrophy in the left hippocampus, along with decreased NLE and NE. The acoustic assessment in Mandarin proves effective in diagnosis and disease monitoring for Mandarin-speaking PD patients, generalizing standardized acoustic guidelines beyond non-tonal languages. The speech impairment in Mandarin-speaking PD patients not only involves motor aspects of speech but also encompasses the cognitive processes underlying language generation.

18.
Front Oncol ; 14: 1380535, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577342

RESUMO

Purpose: The aim of this study was to establish a validated nomogram to predict risk factors for major post-operative complications in patients with rectal cancer (RC) by analyzing the factors contributing to major post-operative complications in RC patients. Methods: We retrospectively collected baseline and surgical information on patients who underwent RC surgery between December 2012 and December 2022 at a single-center teaching hospital. The entire cohort was randomly divided into two subsets (60% of the data for development, 40% for validation). Independent risk factors for major post-operative complications were identified using multivariate logistic regression analyses, and predictive models were developed. Area under the curve (AUC) was calculated using receiver operating characteristic curve (ROC) to assess predictive probability, calibration curves were plotted to compare the predicted probability of the nomogram with the actual probability, and the clinical efficacy of the nomogram was assessed using decision curve analysis (DCA). Results: Our study included 3151 patients who underwent radical surgery for RC, including 1892 in the development set and 1259 in the validation set. Forty (2.1%) patients in the development set and 26 (2.1%) patients in the validation set experienced major post-operative complications. Through multivariate logistic regression analysis, age (p<0.01, OR=1.044, 95% CI=1.016-1.074), pre-operative albumin (p<0.01, OR=0.913, 95% CI=0.866-0.964), and open surgery (p<0.01, OR=2.461, 95% CI=1.284-4.761) were identified as independent risk factors for major post-operative complications in RC, and a nomogram prediction model was established. The AUC of the ROC plot for the development set was 0.7161 (95% Cl=0.6397-0.7924), and the AUC of the ROC plot for the validation set was 0.7191 (95% CI=0.6182-0.8199). The predicted probabilities in the calibration curves were highly consistent with the actual probabilities, which indicated that the prediction model had good predictive ability. The DCA also confirmed the good clinical performance of the nomogram. Conclusion: In this study, a validated nomogram containing three predictors was created to identify risk factors for major complications after radical RC surgery. Due to its accuracy and convenience, it could contribute to personalized management of patients in the perioperative period.

19.
World J Gastrointest Surg ; 16(5): 1344-1353, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38817280

RESUMO

BACKGROUND: Preoperative serum tumor markers not only play a role in the auxiliary diagnosis and postoperative monitoring in colorectal cancer (CRC), but also have been found to have potential prognostic value. AIM: To analyze whether preoperative serum tumor markers, including carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), affect the prognosis of CRC. METHODS: This was a retrospective study conducted in a single center. Patients with nonmetastatic CRC who underwent initial surgery between January 2011 and January 2020 were enrolled and divided into development site and validation site groups at a ratio of 7:3. The independent prognostic factors were screened by Cox regression analysis, and finally, a prognostic nomogram model was established. The newly developed model was tested by internal validation. RESULTS: Eventually, 3526 postoperative patients with nonmetastatic CRC were included in the study. There were 2473 patients at the development site and 1056 patients at the validation site. Age (P < 0.01, HR = 1.042, 95%CI = 1.033-1.051), tumor node metastasis (TNM) classification (P < 0.01, HR = 1.938, 95%CI = 1.665-2.255), preoperative CEA (P = 0.001, HR = 1.393, 95%CI = 1.137-1.707) and CA19-9 (P < 0.01, HR = 1.948, 95%CI = 1.614-2.438) levels were considered independent prognostic factors for patients with nonmetastatic CRC and were used as variables in the nomogram model. The areas under the curve of the development and validation sites were 0.655 and 0.658, respectively. The calibration plot also showed the significant performance of the newly established nomogram. CONCLUSION: We successfully constructed a nomogram model based on age, TNM stage, preoperative CEA, and CA19-9 levels to evaluate the overall survival of patients with nonmetastatic CRC.

20.
Acad Radiol ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871552

RESUMO

RATIONALE AND OBJECTIVES: to develop a deep learning radiomics graph network (DLRN) that integrates deep learning features extracted from gray scale ultrasonography, radiomics features and clinical features, for distinguishing parotid pleomorphic adenoma (PA) from adenolymphoma (AL) MATERIALS AND METHODS: A total of 287 patients (162 in training cohort, 70 in internal validation cohort and 55 in external validation cohort) from two centers with histologically confirmed PA or AL were enrolled. Deep transfer learning features and radiomics features extracted from gray scale ultrasound images were input to machine learning classifiers including logistic regression (LR), support vector machines (SVM), KNN, RandomForest (RF), ExtraTrees, XGBoost, LightGBM, and MLP to construct deep transfer learning radiomics (DTL) models and Rad models respectively. Deep learning radiomics (DLR) models were constructed by integrating the two features and DLR signatures were generated. Clinical features were further combined with the signatures to develop a DLRN model. The performance of these models was evaluated using receiver operating characteristic (ROC) curve analysis, calibration, decision curve analysis (DCA), and the Hosmer-Lemeshow test. RESULTS: In the internal validation cohort and external validation cohort, comparing to Clinic (AUC=0.767 and 0.777), Rad (AUC=0.841 and 0.748), DTL (AUC=0.740 and 0.825) and DLR (AUC=0.863 and 0.859), the DLRN model showed greatest discriminatory ability (AUC=0.908 and 0.908) showed optimal discriminatory ability. CONCLUSION: The DLRN model built based on gray scale ultrasonography significantly improved the diagnostic performance for benign salivary gland tumors. It can provide clinicians with a non-invasive and accurate diagnostic approach, which holds important clinical significance and value. Ensemble of multiple models helped alleviate overfitting on the small dataset compared to using Resnet50 alone.

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