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1.
J Matern Fetal Neonatal Med ; 36(2): 2227310, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37385781

RESUMEN

BACKGROUND: There is ongoing interest in glucocorticoid treatment during oocyte stimulation to treat infertility in women who have undergone Assisted Reproductive Technology (ART). OBJECTIVE: This meta-analysis was performed to evaluate the efficiency and safety of adjuvant glucocorticoid therapy on pregnancy outcomes in infertile women undergoing ART cycles. STUDY DESIGN: A literature search was performed in PubMed, EMBASE, Web of Science, and the Cochrane Library up to December 2022. To assess the efficacy and safety of additional glucocorticoid treatment during ovulation induction in women who underwent IVF or ICSI treatment, only randomized controlled trials were included. RESULTS: Overall, glucocorticoid therapy during ovulation showed a nonsignificant effect of prednisolone improving the live birth rate (OR = 1.03, 95% CI [.75, 1.43], I2 = .0%, p = .84), abortion rate (OR = 1.14, 95% CI [.62, 2.08], I2 = 31%, p = .68), and implantation rate (OR = 1.1, 95% CI [.82, 1.5], I2 = 8%, p = .52) of infertile women compared to the control group. The present meta-analysis revealed that the clinical pregnancy rate per cycle tended to increase after glucocorticoid treatment (OR = 1.29, 95% CI [1.02, 1.63], I2 = 8%, p = .52). CONCLUSIONS: The present meta-analysis suggested that ovarian stimulation prednisolone therapy does not significantly improve clinical outcomes in women undergoing IVF/ICSI. Although the results indicated that adjuvant glucocorticoid therapy during ovarian stimulation may increase the clinical pregnancy rate, subgroup analysis showed that it was affected by infertility factors, dose schedules, and length of treatment. Therefore, these results should be interpreted with caution.


Asunto(s)
Glucocorticoides , Infertilidad Femenina , Femenino , Embarazo , Humanos , Glucocorticoides/uso terapéutico , Infertilidad Femenina/terapia , Inducción de la Ovulación , Prednisolona , Adyuvantes Farmacéuticos , Suplementos Dietéticos
2.
Carbohydr Res ; 521: 108676, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36126413

RESUMEN

Cellulose and pectin are the important components of tobacco (Nicotiana tabacum L.) cell wall, which affect the formation of undesirable compounds. Their contents are closely related to the harmfulness of tobacco. But the simultaneous quantitative analysis of cellulose and pectin is hard to be achieved for traditional analytical methods. A solid-state 13C cross-polarization by multiple contact periods (multiCP) NMR method was developed for the simultaneous quantification of cellulose and pectin in tobacco. The multiCP spectrum at optimal parameters agreed well with the direct polarization (DP) spectrum within one-thirtieth of the measurement time and provided satisfactory signal to noise ratio (SNR). After three simple procedures of sample preparation and spectra deconvolution, simultaneous quantification of cellulose and pectin extracted from tobacco was effectively achieved. Compared with the chemical method, this interesting method was rapid, practicable, and very promising, which provided the technical support for the simultaneous quantification of cell wall substances in biological sample.


Asunto(s)
Celulosa , Pectinas , Pared Celular/química , Celulosa/química , Espectroscopía de Resonancia Magnética/métodos , Pectinas/química , Nicotiana
3.
Int J Anal Chem ; 2022: 5486290, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35371261

RESUMEN

Polyphenols are secondary metabolites of plants and used as effective antioxidants in dietary supplements, whose main sources are fruits, vegetables, and grains. To clarify the content and distribution of polyphenols in different fruit species samples accurately, a rapid and sensitive ultrahigh-pressure liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method combining dispersive liquid-liquid microextraction (DLLME) was developed for quantitative determination of fifteen polyphenol compounds in fruit juice. In this method, the targets were first extracted from 1 g of fruit juice sample using 10 mL of 80% ethanol solution by ultrasonic-assisted extraction (UAE). Then, 1.0 mL of UAE extracted solution, 60 µL of n-octanol and 2.0 mL of H2O were performed in the following DLLME procedure. A C18 reversed-phase column, ZORBAX SB (100 × 4.6 mm, 3.5 µm), was proposed under gradient elution with 0.1% formic acid aqueous solution and methanol mobile phases for the determination of 15 polyphenols, allowing us to obtain polyphenolic profiles in less than 23.0 min. Under the optimum conditions, the enrichment factors ranged from 162 to 194. The results showed that the 15 polyphenols had linear correlation coefficients (R 2) more than 0.99. The limits of detection (LODs) were between 18.3 and 103.5 ng/g, and the average recoveries were between 96.9 and 116.3% with interday relative standard deviations (RSDs) ranging from 4.4 to 8.2% in all cases. The method was successfully applied to the analysis of real fruit juice samples and presented itself as a simple, rapid, practical, and environment-friendly technique.

4.
Int J Biol Sci ; 17(1): 163-177, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33390841

RESUMEN

Cellular communication can be mediated by the exchange of biological information, mainly in the form of proteins and RNAs. This can occur when extracellular vesicles, such as exosomes, secreted by a donor cell are internalized by an acceptor cell. Exosomes bear specific repertoires of proteins and RNAs, indicating the existence of mechanisms that control the sorting of molecules into them. Knowledge about loadings and processes and mechanisms of cargo sorting of exosomes is essential to shed light on the physiological and pathological functions of these vesicles as well as on clinical applications involving their use and/or analysis. In this review, we will discuss the molecular mechanisms associated with exosome secretion and their specific cargo sorting, with special attention to the sorting of RNAs and proteins, and thus the outcome and the emerging therapeutic opportunities of the communication between the exosome-producer and recipient cells.


Asunto(s)
Exosomas/metabolismo , Biogénesis de Organelos , Vías Secretoras , Terapia Biológica , Biomarcadores , Humanos
5.
Wei Sheng Yan Jiu ; 35(3): 355-6, 2006 May.
Artículo en Chino | MEDLINE | ID: mdl-16921767

RESUMEN

OBJECTIVE: To establish a method of determining orlistat in health food by on line HPLC-UV-ESI/MS. METHODS: The separation was completed on an analytical Spherigel C8 column (5 microm, 200 mm x 4.6 mm) with acetonitrile (0.1% formic acid) : water (0.1% formic acid) = 80 : 20 as mobile phase, the detection wavelength was 2003 mm. RESULTS: Good linearity between peak areas and concentrations was obtained during rag of 0.3 - 0.6 mg/ml. CONCLUSION: The method is simple and can be used to determine orlistat in the health food for controlling body weight accurately.


Asunto(s)
Fármacos Antiobesidad/análisis , Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Lactonas/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Humanos , Orlistat
6.
Ann Chim ; 96(5-6): 309-16, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16856760

RESUMEN

In this investigation, a novel two-step simultaneous distillation and solvent extraction (two-step SDE) method was developed to isolate both free and bound aroma in tobacco. Firstly, free aroma were extracted into dichloromethane by SDE for 4 h with SDE sample solution at pH 5.5. Then the SDE sample solution was adjusted to pH 2.5, bound aroma were hydrolyzed, and released as free aroma extracted by fresh dichloromethane. Following, both the free and bound aroma were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The whole isolation procedure of both free and bound aroma was carried out in one SDE apparatus and using one same sample. Especially, the procedure of isolation of bound aroma was greatly simplified. To apply and validate the proposed two-step SDE method, a traditional method were also used to isolate the bound aroma. The total bound aroma obtained by the proposed two-step SDE method and the traditional method were 119.83 mg kg(-1) and 88.9 mg kg(-1), respectively. For isolation of bound aroma, the proposed two-step SDE method was of better extraction recovery, less labourious, solvent and time consuming than the traditional method.


Asunto(s)
Nicotiana/química , Odorantes/análisis , Solventes/química , Cromatografía de Gases/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Extractos Vegetales/aislamiento & purificación , Valores de Referencia , Factores de Tiempo , Volatilización
7.
Anal Bioanal Chem ; 383(5): 869-74, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16211380

RESUMEN

A novel method combining matrix solid phase dispersion (MSPD) with Soxhlet simultaneous extraction clean-up (SSEC) was developed. Being a single-step extraction and clean-up procedure, it could be used instead of multistep solvent extraction and Florisol column clean-up. It not only reduces sample contamination during the procedure, but it also decreases the amount of organic solvent needed. The retention times of standards were used to qualitatively assess the method, and the external standard method was used to quantitatively assess it. Residues of organochlorine pesticides (OCP) in tobaccos were determined by gas chromatography-electron capture detection (GC-ECD), and their identities were confirmed by the standard addition method (SAM). The performance of the method was evaluated and validated: the detection limit was 0.01-0.02 microg g(-1), relative standard deviations were 5-26%, and recoveries were 72-99% at fortification levels of 0.10, 1.00 and 10.0 microg g(-1). The analytical characteristics of MSPD-SSEC compared very favorably with the results from the classical multistep solvent extraction and Florisol column clean-up method.


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía de Gases/métodos , Hidrocarburos Clorados/análisis , Nicotiana/química , Plaguicidas/análisis , Extractos Vegetales/análisis , Hojas de la Planta/química , Contaminantes Ambientales/análisis , Transición de Fase , Polvos
8.
J Chromatogr A ; 1066(1-2): 89-95, 2005 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-15794558

RESUMEN

A high-performance liquid chromatographic method coupled with ultraviolet detection and electrospray ionization mass spectrometry (HPLC-UV-ESI-MS) was developed for simultaneous determination of banned additives-sildenafil, vardenafil and tadalafil in dietary supplements for male sexual potency. The separation was achieved on a C18 column with acetonitrile and aqueous solution (20 mmol ammonium acetate, 0.2% formic acid) as mobile phase at a flow rate of I ml/min with a linear gradient program. UV detection was at 292 nm. Identification of drugs was accomplished using ESI-MS. Good linearity between response (peak area) and concentration was found over a concentration range of 0.8-80 microg/ml for sildenafil; 2.25-225 microg/ml for vardenafil; and 1.1-110 microg/ml for tadalafil, with regression coefficient is better than 0.999. The recovery of the method ranged from 93.3 to 106.1%, and the relative standard deviation varied from 2.0 to 5.6% (n = 6). The method has been successfully applied to the analysis of practical samples of natural dietary supplements.


Asunto(s)
Carbolinas/análisis , Suplementos Dietéticos/análisis , Contaminación de Medicamentos , Imidazoles/análisis , Inhibidores de Fosfodiesterasa/análisis , Piperazinas/análisis , Sulfonas/análisis , Triazinas/análisis , Cromatografía Líquida de Alta Presión , Purinas , Citrato de Sildenafil , Espectrometría de Masa por Ionización de Electrospray , Tadalafilo , Diclorhidrato de Vardenafil
9.
J Pharm Biomed Anal ; 34(3): 695-704, 2004 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-15127826

RESUMEN

A reverse phase high performance liquid chromatography (RP-HPLC) separation coupled with photo diode array detection (DAD) and electrospray ionization mass spectrometry (ESI-MS) detection was established for the analyzing of multiple bioactive compounds in tea and tea extracts. Theanine, chlorogenic acid, purine alkaloids and catechins were identified with authentic standard compounds and with MS-spectra. The content of theanine and catechins was measured by employing DAD and caffeine, chlorogenic acid, theobromine and theopylline by protonated molecular ion on selective ion recording (SIR) mode. The unity of LC/ESI-MS provides more qualitative and quantitative information comparing with general HPLC in the analysis of multi-components in tea, and complex extraction or sample pretreatment is unnecessary. The chromatogram acquired by using this method can be used as a bioactive components fingerprint for the quality control of tea and its extracts. With the help of multi-dimension information of HPLC-DAD-ESIMS, the compounds owning different chemical structure such as amino acid, catechins, etc. in tea and its extracts could be identified and determined in one run successfully.


Asunto(s)
Catequina/análisis , Ácido Clorogénico/análisis , Glutamatos/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , , Alcaloides/análisis , Alcaloides/química , Catequina/química , Ácido Clorogénico/química , Cromatografía Líquida de Alta Presión/métodos , Glutamatos/química , Extractos Vegetales/análisis , Extractos Vegetales/química , Purinas/análisis , Purinas/química
10.
Wei Sheng Yan Jiu ; 33(1): 108-10, 2004 Jan.
Artículo en Chino | MEDLINE | ID: mdl-15098493

RESUMEN

The volatile fragrant components in hawthorn tincture were analyzed by GC/MS. 38 components were identified. The relative content of these constituents were determined with area mormalizing method and the identification ratio was 97.19%. The main components were 3-Hexen-1-ol(370.59 micrograms/g), Eugenol(320.95 micrograms/g), Butanedioic acid hydroxy, diethyl ester(191.25 micrograms/g), 2-Methyl-pentenoic acid(164.83 micrograms/g) and citric acid(80.87 micrograms/g) etc. The method is simple, rapid and highly sensitive and suitable for routine analysis and quality control.


Asunto(s)
Crataegus/química , Eugenol/análisis , Hexanoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/análisis , Extractos Vegetales/análisis , Pirimetamina , Control de Calidad , Sensibilidad y Especificidad , Ácido Succínico/análisis
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