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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(11): 1862-1868, 2023 Nov 06.
Artigo em Chinês | MEDLINE | ID: mdl-38008578

RESUMO

This study used machine learning techniques combined with routine blood cell analysis parameters to build preliminary prediction models, helping differentiate patients with depression from healthy controls, or patients with anxiety. A multicenter study was performed by collecting blood cell analysis data of Beijing Chaoyang Hospital and the First Hospital of Hebei Medical University from 2020 to 2021. Machine learning techniques, including support vector machine, decision tree, naïve Bayes, random forest and multi-layer perceptron were explored to establish a prediction model of depression. The results showed that based on the blood cell analysis results of healthy controls and depression group, the accuracy of prediction model reached as high as 0.99, F1 was 0.975. Receiver operating characteristic curve area and average accuracy were 0.985 and 0.967, respectively. Platelet parameters contributed mostly to depression prediction model. While, to random forest differential diagnosis model based on the data from depression and anxiety groups, prediction accuracy reached 0.68 and AUC 0.622. Age, platelet parameters, and average volume of red blood cells contributed the most to the model. In conclusion, the study researched on the prediction model of depression by exploring blood cell analysis parameters, revealing that machine learning models were more objective in the evaluation of mental illness.


Assuntos
Depressão , Aprendizado de Máquina , Humanos , Teorema de Bayes , Máquina de Vetores de Suporte , Contagem de Células Sanguíneas
2.
Nature ; 620(7976): 961-964, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37339734

RESUMO

Spider pulsars are neutron stars that have a companion star in a close orbit. The companion star sheds material to the neutron star, spinning it up to millisecond rotation periods, while the orbit shortens to hours. The companion is eventually ablated and destroyed by the pulsar wind and radiation1,2. Spider pulsars are key for studying the evolutionary link between accreting X-ray pulsars and isolated millisecond pulsars, pulsar irradiation effects and the birth of massive neutron stars3-6. Black widow pulsars in extremely compact orbits (as short as 62 minutes7) have companions with masses much smaller than 0.1 M⊙. They may have evolved from redback pulsars with companion masses of about 0.1-0.4 M⊙ and orbital periods of less than 1 day8. If this is true, then there should be a population of millisecond pulsars with moderate-mass companions and very short orbital periods9, but, hitherto, no such system was known. Here we report radio observations of the binary millisecond pulsar PSR J1953+1844 (M71E) that show it to have an orbital period of 53.3 minutes and a companion with a mass of around 0.07 M⊙. It is a faint X-ray source and located 2.5 arcminutes from the centre of the globular cluster M71.

3.
Zhonghua Nei Ke Za Zhi ; 61(9): 1023-1030, 2022 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-36008295

RESUMO

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ2 test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.


Assuntos
Carcinoma de Células Pequenas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Histiocitoma Fibroso Maligno , Melanoma , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Masculino
5.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 54(11): 843-849, 2019 Nov 07.
Artigo em Chinês | MEDLINE | ID: mdl-31795546

RESUMO

Objective: The aging model of guinea pigs induced by D-galactose was set up to investigate the changes of BK(Ca) expression and function on cochlear pericytes and their relationship with age-related hearing loss. Methods: Thirty healthy 8-week-old guinea pigs were randomly divided into three groups, with 10 in each group: D-galactose aging model group, subcutaneous injection of D-galactose (500 mg/kg) daily for 6 weeks; saline control group, the same amount of saline was injected into the neck of the aging model group for 6 weeks; the blank control group, no treatment was performed. The threshold of auditory brainstem response (ABR) was detected. The content of BK(Ca) in the perivascular cells of the guinea pig cochlear cells was detected by immunofluorescence technique. The changes of peripheral current density and BK(Ca) current were detected by patch clamp technique. The data were analyzed by GraphPad Prism software. Results: Compared with the saline group and the control group, the ABR threshold and the amplitude of the wave I were significantly decreased in the aging model group, and the difference was statistically significant (P<0.01). Compared with the control group, the expression of BK(Ca) in the vascular pericytes of guinea pigs in the aging model group was significantly reduced (1.00±0.08 vs 0.27±0.03,the difference was statistically significant P<0.01), and the cell current density and BK(Ca) net current value were also significantly reduced with statistically significant (P<0.01). Conclusions: D-galactose can successfully induce guinea pig aging model, in which BK(Ca) expression decreases and net current value decreases in pericytes of cochlear striavascularis, and changes in BK(Ca) expression and function may be related to age-related hearing loss.


Assuntos
Cóclea/metabolismo , Doenças Cocleares/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/biossíntese , Pericitos/metabolismo , Presbiacusia/metabolismo , Animais , Cóclea/patologia , Cóclea/fisiopatologia , Doenças Cocleares/induzido quimicamente , Doenças Cocleares/patologia , Doenças Cocleares/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico , Galactose/administração & dosagem , Galactose/efeitos adversos , Cobaias , Modelos Animais , Presbiacusia/induzido quimicamente , Presbiacusia/patologia , Presbiacusia/fisiopatologia , Distribuição Aleatória
6.
Proc Inst Mech Eng H ; 222(3): 377-91, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18491706

RESUMO

This study applies the methodology and procedure of process capability to investigate a solid free-form fabrication technique as a manufacturing method to produce scaffold moulds for tissue engineering. The process capability Cpk and process performance Ppk of scaffold mould manufacture using a solid free-form fabrication technique has been analysed with respect to the dimension deviations. A solid free-form fabrication machine T66 was used to fabricate scaffold moulds in this study and is able to create features that ranged from 200 microm to 1000 microm. The analysis showed that the printing process under the normal cooling conditions of the printing chamber was in statistical control but gave low process capability indices, indicating that the process was 'inadequate' for production of 'dimension-consistent' scaffold moulds. The study demonstrates that, by lowering the temperature of the cooling conditions, the capability Cpk of the printing process can be improved (about threefold) sufficiently to ensure the consistent production of scaffold moulds with dimension characteristics within their specification limits.


Assuntos
Teste de Materiais/métodos , Distribuições Estatísticas , Engenharia Tecidual/instrumentação , Engenharia Tecidual/normas , Alicerces Teciduais/normas , Materiais Biocompatíveis/normas , Interpretação Estatística de Dados , Análise de Falha de Equipamento/estatística & dados numéricos , Temperatura Alta/efeitos adversos , Humanos , Controle de Qualidade , Padrões de Referência , Valores de Referência , Engenharia Tecidual/estatística & dados numéricos , Alicerces Teciduais/estatística & dados numéricos , Pesos e Medidas
7.
J Biomed Mater Res B Appl Biomater ; 85(2): 519-28, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18076093

RESUMO

This article reports the mechanical properties and in vitro evaluation of a collagen scaffold fabricated using an indirect 3D printing technique. Collagen scaffolds, featuring predefined internal channels and capillary networks, were manufactured using phase change printing. It was observed that the collagen scaffolds featured internal channels and a hierarchical structure that varied over length scales of 10-400 microm. In vitro evaluation using hMSCs demonstrated that the resultant collagen based scaffolds have the ability to support hMSC cell attachment and proliferation; cells can migrate and survive deep within the structure of the scaffold. The cell numbers increased 2.4 times over 28 days in culture for the lysine treated scaffolds. The cells were spread along the collagen fibers to form a 3D structure and extracellular matrix was detected on the surface of the scaffolds after 4 weeks in culture. The crosslinking treatment enhanced the biostability and dynamic properties of the collagen scaffolds significantly.


Assuntos
Colágeno , Engenharia Tecidual , Animais , Bovinos , Proliferação de Células , Células Cultivadas , Humanos , Teste de Materiais/métodos , Engenharia Tecidual/métodos
8.
Yao Xue Xue Bao ; 28(8): 572-6, 1993.
Artigo em Chinês | MEDLINE | ID: mdl-8285064

RESUMO

The protective action of Glycyrrhiza flavonoids (GF), the major components in the radix of Glycyrrhiza, on carbon tetrachloride-induced hepatotoxicity was investigated. The carbon tetrachloride-induced increases of serum glutamic-pyruvic transaminase and lactate dehydrogenase were significantly inhibited by GF dose-dependently. Carbon tetrachloride-induced necrosis in mice were ameliorated by GF pretreatment. Concomitantly, the carbon tetrachloride-induced elevation of MDA in the liver was lowered by GF. GF neither reduced the activities of the two enzymes in normal mouse sera nor directly inhibited the activities of the two enzymes in the serum. These findings suggest that the anti-lipid peroxidation effect of GF was contributed to its protective action against carbon tetrachloride-induced hepatotoxicity.


Assuntos
Intoxicação por Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Flavonoides/farmacologia , Glycyrrhiza , Fígado/patologia , Plantas Medicinais , Alanina Transaminase/sangue , Animais , Intoxicação por Tetracloreto de Carbono/metabolismo , Intoxicação por Tetracloreto de Carbono/patologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Glutationa/metabolismo , Glycyrrhiza/química , L-Lactato Desidrogenase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos
9.
Yao Xue Xue Bao ; 27(1): 5-9, 1992.
Artigo em Chinês | MEDLINE | ID: mdl-1529714

RESUMO

Astragalus Polysaccharide (APS), an active component, was isolated from the radix of Astragalus membranaceus Bge var. mongholicus (Bge) Hsiao, and the effects of APS on E. coli endotoxin-induced liver damage were investigated in mice. The results showed that when mice were pretreated with APS (30, 60, 100 mg.kg-1.d-1 x 7d, ip), the survival rate of endotoxin intoxicated mice was increased the lowering of ATP levels and adenylate energy charge in mouse liver could be prevented. APS 100 mg.kg-1 could protect the mice from death on endotoxin (25 mg.kg-1) intoxication; and the level of ATP, the value of adenylate energy charge in the protected mouse liver were almost recovered to normal range. The effects of APS were shown to be dose-dependent. Concomitantly, the increase of MDA and decrease of GSH in mouse liver could be corrected by APS pretreatment. The results revealed that APS has an antioxidative action. An ultramicroscopic examination showed that the injury of the bio-membrane and the crest of mitochondria were ameliorated by APS pretreatment. These findings suggest that the protective effects of APS on E. coli endotoxin intoxicated mice may be due to its antioxidative action to protect the mitochondria bio-membrane, therefore, the adenylate metabolism is improved in mouse liver.


Assuntos
Plantas Medicinais , Polissacarídeos/farmacologia , Toxemia/tratamento farmacológico , Trifosfato de Adenosina/metabolismo , Animais , Astragalus propinquus , Relação Dose-Resposta a Droga , Endotoxinas , Escherichia coli , Glutationa , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Mitocôndrias Hepáticas/ultraestrutura , Plantas Medicinais/química , Polissacarídeos/uso terapêutico , Toxemia/etiologia , Toxemia/metabolismo
10.
Zhongguo Yao Li Xue Bao ; 11(6): 539-41, 1990 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-1966656

RESUMO

The antiperoxidant action of berbamine (Ber) was demonstrated by colorimetric estimation of malondialdehyde (MDA) formation, and the scavenging effect of Ber on O2- was investigated by chemiluminescence method and ESR-spin trapping technique. Ber 11-100 mumol/L remarkably inhibited MDA formation induced by incubating mice liver homogenate at 37 degrees C with vibration for 1 h. Ber 1-100 mumol/L and 0.2-0.6 mmol/L effectively scavenged O2- in alkaline DMSO and xanthine/xanthine oxidase systems respectively. The results show that Ber is an antioxidant.


Assuntos
Alcaloides/farmacologia , Antioxidantes , Benzilisoquinolinas , Animais , Espectroscopia de Ressonância de Spin Eletrônica , Sequestradores de Radicais Livres , Radicais Livres , Técnicas In Vitro , Fígado/metabolismo , Medições Luminescentes , Masculino , Malondialdeído/metabolismo , Camundongos , Oxigênio/metabolismo
11.
Zhongguo Yao Li Xue Bao ; 11(5): 466-70, 1990 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-1966652

RESUMO

The scavenging effects of sodium ferulate (SF) and glycyrrhetic acid (GA) on oxygen free radicals were studied by using spin trapping technique and chemiluminescence (CL) methods. SF 0.3 mmol/L and GA 0.3 mmol/L effectively scavenged oxygen free radicals produced by phorbol myristate acetate (PMA)-stimulated polymorphonuclear leukocytes (PMN), but had no effect on the oxygen consumption by PMN, measured with spin probe oxymetry. In 3 cell-free oxygen free radical generating systems, both SF and GA showed a remarkably scavenging effects on O2- and OH.. SF 30 mumol/L and GA 30 mumol/L prominently inhibited the CL response of PMA-stimulated PMN. The results demonstrated that SF and GA are oxygen free radical scavengers.


Assuntos
Ácidos Cumáricos/farmacologia , Sequestradores de Radicais Livres , Ácido Glicirretínico/farmacologia , Neutrófilos/efeitos dos fármacos , Oxigênio/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Humanos , Medições Luminescentes
12.
Biochem Pharmacol ; 39(11): 1673-8, 1990 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2160816

RESUMO

The scavenging effect of berbamine (Ber) on active oxygen radicals was studied, using a spin-trapping technique and a chemiluminescence (CL) method in phorbol myristate acetate (PMA) stimulated polymorphonuclear leukocytes (PMN) and in four cell-free superoxide (O2-.) or hydroxyl radical (OH.) generating systems. Ber (0.1 to 0.3 mM) effectively reduced active oxygen radicals in PMN stimulated with PMA, but had no obvious effect on oxygen consumption during the respiratory burst of PMN, measured with spin probe oxymetry. Ber (0.3 mM) prominently inhibited the CL response of PMA-stimulated PMN. The agent remarkably quenched O2-. in xanthine/xanthine oxidase and irradiation riboflavin systems and OH. in the Fenton reaction. Its scavenging action on O2-. was stronger than that of Vitamin E in the xanthine/xanthine oxidase system but the same as Vitamin E in the riboflavin system, and its action on OH. was similar to that of Vitamin E.


Assuntos
Alcaloides/farmacologia , Benzilisoquinolinas , Hidróxidos/metabolismo , Neutrófilos/metabolismo , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Óxidos N-Cíclicos/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Humanos , Radical Hidroxila , Neutrófilos/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Riboflavina/metabolismo , Marcadores de Spin , Xantina Oxidase/metabolismo
13.
Yao Xue Xue Bao ; 24(11): 807-12, 1989.
Artigo em Chinês | MEDLINE | ID: mdl-2618676

RESUMO

The antiperoxidant activity of glycyrrhiza flavonoid (FG) was studied by using colorimetric estimation of lipid peroxide (MDA) formation. The scavenging effects of FG on O2-. and OH. was investigated by using chemiluminescence method and spin trapping technique in different systems. The results were as follows: FG 2.8-25 micrograms/ml effectively inhibited MDA formation induced by incubating mice liver homogenate at 37 degrees C for 1 h; FG 0.265-26.5 micrograms/ml or 2.58-258 micrograms/ml was shown to markedly scavenge O2-. in alkaline/DMSO or xanthine/xanthine oxidase systems, respectively in a concentration-dependent manner. FG 144 micrograms/ml or 258 micrograms/ml also significantly scavenged the active oxygen radicals produced by PMN stimulation with PMA or OH. produced in Fenton's reaction respectively. The results suggest that FG may be used as an antioxidant.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Glycyrrhiza , Peroxidação de Lipídeos/efeitos dos fármacos , Plantas Medicinais , Animais , Radicais Livres , Humanos , Camundongos , Oxigênio/metabolismo
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