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1.
Biosensors (Basel) ; 13(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37998153

RESUMO

The swine fever virus seriously affects pork production, and to improve pork production, pig breeding efficiency needs to be improved, and the detection of boar sperm activity is an important part of the pig breeding process. Traditional laboratory testing methods rely on bulky testing equipment, such as phase-contrast microscopes, high-speed cameras, and computers, which limit the testing scenarios. To solve the above problems, in this paper, a microfluidic chip was designed to simulate sperm in the oviduct with a channel thickness of 20 um, which can only accommodate sperm for two-dimensional movement. A miniature microscope system which can be used in combination with a smartphone is designed that is only the size of the palm of the hand and has a magnification of about 38 times. An intelligent diagnostic app was developed using Java language, which can automatically identify and track boar sperm with a recognition rate of 96.08% and an average tracking rate of 86%. The results show that the proposed smartphone-based hand-held platform can effectively replace the traditional microscope compound computer to diagnose sperm activity. In contrast, the platform is smaller, easier to use and is not limited by the usage scenarios.


Assuntos
Smartphone , Motilidade dos Espermatozoides , Humanos , Feminino , Suínos , Masculino , Animais , Sêmen , Espermatozoides , Tubas Uterinas
2.
Steroids ; 71(2): 96-101, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16289174

RESUMO

The 7-substituted-5-androstene derivatives 2a-10a and 2b-10b were prepared by reaction of 3beta,17beta-di(tert-butyldimethylsilyloxy)-5-androsten-7-one 1 with different organic halides. The resulting 7alpha- and 7beta-isomers were carefully separated by column chromatography. The structural assignments of the 7alpha- and 7beta-isomers were determined by 13C-NMR.


Assuntos
Androstenos/síntese química , Iodetos/química , Samário/química , Isótopos de Carbono , Cromatografia/métodos , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular , Estereoisomerismo
3.
J Org Chem ; 68(4): 1603-6, 2003 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-12585916

RESUMO

The 7beta-methyl-5-androstene derivatives 11a-c were prepared in good yield with high stereoselectivities starting from 3beta-acetoxyandrost-5-en-17-one 4. The addition of methylmagnesium iodide to the 7-carbonyl group of 7a-c gave, after hydrolysis, two isomers 9a-c and 10a-c, which were stereoselectively deoxygenated by means of an ionic hydrogenation to afford the compounds 11a-c.


Assuntos
Androstenos/síntese química , Técnicas de Química Combinatória , Catálise , Hidrólise , Metilação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oxirredução , Estereoisomerismo , Difração de Raios X
4.
Zhonghua Zhong Liu Za Zhi ; 24(2): 129-32, 2002 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12015032

RESUMO

OBJECTIVE: To study the reversal effect of nomegestrol acetate (NOM) on mutidrug resistance (MDR) in MCF7/ADR and its mechanism. METHODS: Using tetrazolium dye assay, effects of various concentrations of NOM on sensitivity to ADR in MCF7/ADR was studied. Expression of MDR related genes MDR1, glutathoine S-transferase Pi (GSTpi), Topoisomerase II alpha (Topo II alpha) and MDR related protein (MRP) were assayed by reverse transcription-polymerase chain reaction (RT-PCR) and immunocytochemistry assay. Using flow cytometry (FCM), intracellular ADR concentration effects on cell cycle were observed. RESULTS: NOM significantly reversed MDR in MCF7/ADR. After NOM 20, 10 and 5 micromol/L treatment, the chemosensitivity to ADR increased to 21, 12 and 8 times. The reversal activity of NOM was stronger than that of the precursor compound megestrol acetate, and was comparable to that of verapamail. After treatment with NOM 5 micromol/L both MDR1 and GSTpi mRNA genes expression began to decline on D2 (P < 0.05, & P < 0.01) and reached the lowest level on D3 (both P < 0.01), but the expression levels began to rise on D6 again (both P < 0.05). The expression of MRP and Topo II alpha gave no significant change. Changes of P-gp and GSTpi protein expressions were similar to those of their mRNA expressions, showing early decline and late rise. Two hours after NOM 20, 10, and 5 micromol/L treatment, intracellular ADR concentration increased 2.7, 2.3 and 1.5 times, respectively. FCM data showed that after forty-eight hours, combined administration of NOM (20 micromol/L) and ADR (from low concentration to high concentration), MCF7/ADR cells showed gradual arrest in the G(2)M phase with the increase of ADR dose. CONCLUSION: NOM has strong reversal effects on MDR in MCF7/ADR. The reversal takes place via different routes, i.e. down regulating mRNA and protein expression levels of MDR1 and GSTpi, increasing intracellular drug concentration, and enhancing the arrest of ADR in cells at G(2)M phase.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Neoplasias da Mama/genética , Megestrol , Norpregnadienos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antígenos de Neoplasias , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glutationa S-Transferase pi , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Imuno-Histoquímica , Concentração Inibidora 50 , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Congêneres da Progesterona/farmacologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Verapamil/farmacologia
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