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1.
Skin Res Technol ; 30(5): e13720, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38743384

RESUMEN

BACKGROUND: Sensitive skin is hypersensitive to various external stimuli and a defective epidermal permeability barrier is an important clinical feature of sensitive skin. Claudin-5 (CLDN5) expression levels decrease in sensitive skin. This study aimed to explore the impact of CLDN5 deficiency on the permeability barrier in sensitive skin and the regulatory role of miRNAs in CLDN5 expression. MATERIALS AND METHODS: A total of 26 patients were retrospectively enrolled, and the CLDN5 expression and permeability barrier dysfunction in vitro were assessed. Then miRNA-224-5p expression was also assessed in sensitive skin. RESULTS: Immunofluorescence and electron microscopy revealed reduced CLDN5 expression, increased miR-224-5p expression, and disrupted intercellular junctions in sensitive skin. CLDN5 knockdown was associated with lower transepithelial electrical resistance (TEER) and Lucifer yellow penetration in keratinocytes and organotypic skin models. The RNA-seq and qRT-PCR results indicated elevated miR-224-5p expression in sensitive skin; MiR-224-5p directly interacted with the 3`UTR of CLDN5, resulting in CLDN5 deficiency in the luciferase reporter assay. Finally, miR-224-5p reduced TEER in keratinocyte cultures. CONCLUSION: These results suggest that the miR-224-5p-induced reduction in CLDN5 expression leads to impaired permeability barrier function, and that miR-224-5p could be a potential therapeutic target for sensitive skin.


Asunto(s)
Claudina-5 , MicroARNs , Permeabilidad , Piel , Adulto , Femenino , Humanos , Masculino , Claudina-5/genética , Claudina-5/metabolismo , Queratinocitos/metabolismo , MicroARNs/metabolismo , MicroARNs/genética , Estudios Retrospectivos , Piel/metabolismo
2.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1526-1539, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621936

RESUMEN

This study aims to investigate the component variations and spatial distribution of ginsenosides in Panax quinquefolium roots during repeated steaming and drying. Ultra performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was employed to identify the ginsenosides in the root extract. Matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) was employed to visualize the spatial distribution and spatiotemporal changes of prototype ginsenosides and metabolites in P. quinquefolium roots. The UPLC results showed that 90 ginsenosides were identified during the steaming process of the roots, and polar ginsenosides were converted into low polar or non-polar ginsenosides. The content of prototype ginsenosides decreased, while that of rare ginsenosides increased, which included 20(S/R)-ginsenoside Rg_3, 20(S/R)-ginsenoside Rh_2, and ginsenosides Rk_1, Rg_5, Rs_5, and Rs_4. MALDI-MSI results showed that ginsenosides were mainly distributed in the epidermis and phloem. As the steaming times increased, ginsenosides were transported to the xylem and medulla. This study provides fundamental information for revealing the changes of biological activity and pharmacological effect of P. quinquefolium roots that are caused by repeated steaming and drying and gives a reference for expanding the application scope of this herbal medicine.


Asunto(s)
Ginsenósidos , Panax , Ginsenósidos/análisis , Espectrometría de Masas en Tándem , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Panax/química , Cromatografía Líquida de Alta Presión/métodos , Raíces de Plantas/química
3.
Hum Reprod ; 38(3): 334-351, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36728671

RESUMEN

Extracellular vesicles (EVs) are nano-sized membrane-bounded particles, released by all cells and capable of transporting bioactive cargoes, proteins, lipids, and nucleic acids, to regulate a variety of biological functions. Seminal plasma is enriched in EVs, and extensive evidence has revealed the role of EVs (e.g. prostasomes and epididymosomes) in the male genital tract. Recently, EVs released from testicular cells have been isolated and identified, and some new insights have been generated on their role in maintaining normal spermatogenesis and steroidogenesis in the testis. In the seminiferous tubules, Sertoli cell-derived EVs can promote the differentiation of spermatogonial stem cells (SSCs), and EVs secreted from undifferentiated A spermatogonia can inhibit the proliferation of SSCs. In the testicular interstitium, EVs have been identified in endothelial cells, macrophages, telocytes, and Leydig cells, although their roles are still elusive. Testicular EVs can also pass through the blood-testis barrier and mediate inter-compartment communication between the seminiferous tubules and the interstitium. Immature Sertoli cell-derived EVs can promote survival and suppress the steroidogenesis of Leydig cells. Exosomes isolated from macrophages can protect spermatogonia from radiation-induced injury. In addition to their role in intercellular communication, testicular EVs may also participate in the removal of aberrant proteins and the delivery of antigens for immune tolerance. EVs released from testicular cells can be detected in seminal plasma, which makes them potential biomarkers reflecting testicular function and disease status. The testicular EVs in seminal plasma may also affect the female reproductive tract to facilitate conception and may even affect early embryogenesis through modulating sperm RNA. EVs represent a new type of intercellular messenger in the testis. A detailed understanding of the role of testicular EV may contribute to the discovery of new mechanisms causing male infertility and enable the development of new diagnostic and therapeutic strategies for the treatment of infertile men.


Asunto(s)
Vesículas Extracelulares , Infertilidad Masculina , Masculino , Femenino , Humanos , Testículo/metabolismo , Células Endoteliales , Semen , Espermatogénesis/fisiología , Espermatogonias , Células de Sertoli/metabolismo , Infertilidad Masculina/metabolismo
4.
J Assist Reprod Genet ; 40(9): 2251-2266, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37553495

RESUMEN

PURPOSE: To reveal the underlying roles that pyroptosis-related genes (PRGs) played in human spermatogenic dysfunction. METHODS: One discovery set and three validation sets were employed to inspect the previously reported 33 PRGs in the human testis with different status of spermatogenesis. PRGs that differentially expressed in all sets were considered as key differentially expressed pyroptosis-related genes (PR-DEGs). The relationships between key PR-DEGs and samples' clinicopathological, therapeutic, and immune patterns were respectively studied. Single-cell RNA sequencing (scRNS-seq) analyses were conducted to show the expression changes and related mechanisms of key PR-DEGs at a single-cell resolution. RESULTS: CASP4 and GPX4 were identified as two key PR-DEGs. These two genes were significantly dysregulated in spermatogenic dysfunctional samples, but with opposite tendency. CASP4 was negatively correlated with Johnsen scores but positively correlated with follicle-stimulating hormone (FSH) levels (all p < 0.05), while GPX4 exhibited significant positive correlations with Johnsen scores and negative relevance with FSH. For treatments, both molecules showed a prospective value of being predictors for sperm retrieval surgeries. Moreover, CASP4 and GPX4 were potential immunoregulators in the testicular immune microenvironment and showed significant correlations to testicular macrophages and mast cell infiltration. In scRNA-seq analyses, GPX4 was highly expressed in germ cells, which therefore suffered a sharp reduction with the loss of germ cells in spermatogenic dysfunction. On the other hand, CASP4 were basically somatic cell-derived, and the proportion of CASP4-positive Leydig cells significantly increased in disease testes (p = 0.0001). CONCLUSION: In all, we revealed two key PRGs of human testes that might be functional in spermatogenic dysfunction.


Asunto(s)
Piroptosis , Testículo , Humanos , Masculino , Testículo/metabolismo , Estudios Prospectivos , Piroptosis/genética , Semen , Espermatogénesis/genética , Hormona Folículo Estimulante/metabolismo
5.
Mol Hum Reprod ; 28(2)2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-35088858

RESUMEN

Reciprocal communication between Sertoli and Leydig cells occurs in the testes; however, the detailed mechanisms involved are not completely understood. Exosomes can communicate within neighboring or distant cells to regulate cell function. Our aim was to determine whether exosomes released from Sertoli cells can regulate the survival of Leydig cells. We found that exosomes released from rat primary Sertoli cells could be internalized by Leydig cells in vitro, and promote the survival of Leydig cells, as assessed by optical density at 450 nm, compared to untreated control (mean ± SD: 0.95 ± 0.04 vs 0.79 ± 0.03, P < 0.05). When the exosomes were injected into the interstitial area of rat testis, they could also be internalized by Leydig cells in vivo. To investigate if exosomes released from Sertoli cells can reach Leydig cells in vivo, exosomes were injected into the efferent duct, from where they entered the interstitial space from seminiferous tubules, which indicated that they may cross the blood-testis barrier (BTB). Further in vitro studies found that exosomes released from Sertoli cells significantly increased CC-chemokine ligand 20 (Ccl20) mRNA (mean ± SD: 2.79 ± 0.08 vs 0.98 ± 0.04, P < 0.01) and protein (mean ± SD: 1.08 ± 0.06 vs 0.53 ± 0.05 ng/ml, P < 0.01) levels in Leydig cells, compared to the untreated Leydig cells. CCL20 promoted the phosphorylation of AKT (protein kinase B) in Leydig cells, compared to untreated control (mean ± SD: 0.074 ± 0.002 vs 0.051 ± 0.002, P < 0.01). In conclusion, our results demonstrated that exosomes released by Sertoli cells may cross the BTB and promote the survival of Leydig cells. The findings may add new evidence for Sertoli-Leydig cell communication.


Asunto(s)
Exosomas , Células de Sertoli , Animales , Células Intersticiales del Testículo , Masculino , Ratas , Túbulos Seminíferos , Células de Sertoli/fisiología , Testículo/fisiología
6.
J Sep Sci ; 38(8): 1419-25, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25676868

RESUMEN

A method combining accelerated solvent extraction with dispersive liquid-liquid microextraction was developed for the first time as a sample pretreatment for the rapid analysis of phenols (including phenol, m-cresol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol) in soil samples. In the accelerated solvent extraction procedure, water was used as an extraction solvent, and phenols were extracted from soil samples into water. The dispersive liquid-liquid microextraction technique was then performed on the obtained aqueous solution. Important accelerated solvent extraction and dispersive liquid-liquid microextraction parameters were investigated and optimized. Under optimized conditions, the new method provided wide linearity (6.1-3080 ng/g), low limits of detection (0.06-1.83 ng/g), and excellent reproducibility (<10%) for phenols. Four real soil samples were analyzed by the proposed method to assess its applicability. Experimental results showed that the soil samples were free of our target compounds, and average recoveries were in the range of 87.9-110%. These findings indicate that accelerated solvent extraction with dispersive liquid-liquid microextraction as a sample pretreatment procedure coupled with gas chromatography and mass spectrometry is an excellent method for the rapid analysis of trace levels of phenols in environmental soil samples.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Extracción Líquido-Líquido , Fenoles/química , Suelo/química , Solventes/química , Acetona/química , Clorobencenos/química , Clorofenoles/química , Cresoles/química , Cinética , Límite de Detección , Reproducibilidad de los Resultados
7.
Anal Bioanal Chem ; 406(15): 3787-93, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24748445

RESUMEN

This study aims to investigate the feasibility of etched sand particles being used as solid-phase extraction adsorbents to enrich polychlorinated biphenyls (PCBs), which are typical persistent organic pollutants in the environment, at trace levels. Gas chromatography-tandem mass spectrometry was selected to detect the compounds. Etched sand particles exhibited excellent merits on the enrichment of PCBs. Related important factors affecting extraction efficiencies were investigated and optimized in detail. Under optimized conditions, low limits of detection (0.42 to 3.69 ng L(-1)), wide linear range (10 to 1,000 ng L(-1)), and high repeatability (1.9 to 8.2%) were achieved. The developed method was validated with several real water samples, and satisfactory results were obtained. All of these findings indicate that etched sand particles would be useful for the enrichment and determination of organic pollutants at trace levels in water samples.


Asunto(s)
Monitoreo del Ambiente/métodos , Ácido Fluorhídrico/análisis , Bifenilos Policlorados/análisis , Purificación del Agua/métodos , Adsorción , Cromatografía de Gases , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Límite de Detección , Dióxido de Silicio , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Agua , Contaminantes Químicos del Agua/análisis , Contaminación del Agua
8.
J Sep Sci ; 37(12): 1496-502, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24723552

RESUMEN

We have investigated the feasibility of bamboo charcoal@iron oxide black for the headspace solid-phase microextraction of polychlorinated biphenyls in environmental water samples. Bamboo charcoal@iron oxide black was prepared and used as a solid-phase microextraction coating material, and gas chromatography with tandem mass spectrometry was used for detection. Several important factors affecting the extraction efficiency were systematically investigated and optimized. Under the optimum conditions, the experimental data exhibited wide linear range over the range 0.2-1000 ng/L and low limits of detection in the range of 4.7-22.2 pg/L. The novel coating was successfully used for the enrichment and determination of polychlorinated biphenyls in real environmental water samples. All these results indicated that bamboo charcoal@iron oxide black-based headspace solid-phase microextraction coupled to gas chromatography with tandem mass spectrometry was an excellent alternative for the sensitive analysis of polychlorinated biphenyls at ultratrace levels in the environment.


Asunto(s)
Bifenilos Policlorados/aislamiento & purificación , Microextracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Bambusa/química , Carbón Orgánico/química , Compuestos Férricos/química , Cromatografía de Gases y Espectrometría de Masas , Bifenilos Policlorados/química , Sensibilidad y Especificidad , Microextracción en Fase Sólida/instrumentación , Contaminantes Químicos del Agua/química , Contaminación Química del Agua/análisis
9.
Zhonghua Nan Ke Xue ; 20(7): 586-94, 2014 Jul.
Artículo en Zh | MEDLINE | ID: mdl-25095614

RESUMEN

Male infertility is a common and complex disease in urology and andrology, and for many years there has been no effective surgical treatment. With the emergence of microsurgery and assisted reproductive medicine (IVF/ICSI), rapid development has been achieved in the treatment of male infertility. The Center for Male Reproductive Medicine and Microsurgery at Weill Cornell Medical College of Cornell University has been playing an important leading role in developing microsurgical techniques for the management of male infertility. The development of microsurgical treatment of male infertility in China has experienced the 3 periods of emerging, making, and boosting ever since its systematic introduction from Weill Cornell Medical College 15 years ago. At present, many Chinese hospitals have adopted microsurgery in the management of male infertility, which has contributed to the initial establishment of a microsurgical treatment system for male infertility in China. However, some deficiencies do exist concerning microsurgical treatment of male infertility, as in normalized technical training programs for competent surgeons, unified criteria for evaluation of surgical outcomes, and detailed postoperative follow-up data. This article presents an overview on the 15-year development of microsurgical management of male infertility in China, points out the existing deficiencies, and offers some propositions for the promotion of its development.


Asunto(s)
Infertilidad Masculina/cirugía , Microcirugia , China , Humanos , Masculino
10.
J Hazard Mater ; 465: 133468, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38219584

RESUMEN

Microporous organic networks (MONs) are highly porous materials that are particularly useful in analytical chemistry. However, the use of these materials is often limited by the functional groups available on their surface. Here, we described the polymerization of a sea urchin-like structure material at ambient temperature, that was functionalized with hydroxyl, carboxyl, and triazine groups and denoted as OH-COOH-MON-TEPT. A substantial proportion of OH-COOH-MON-TEPT was intricately decorated EDA-Fe3O4, creating a well-designed configuration (EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC) for superior adsorption of the target analytes phenylurea herbicides (PUHs) via magnetic solid-phase extraction (MSPE). The proposed method showed remarkably low limits of detection ranging from 0.03 to 0.22 ng·L-1. Experimental investigations and theoretical analyses unveiled the adsorption mode between EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC and PUHs. These findings establish a robust foundation for potential applications of EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC in the analysis of various polar contaminants.

11.
Anal Bioanal Chem ; 405(14): 4993-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23529412

RESUMEN

This study demonstrates the potential of bamboo charcoal as a novel and inexpensive solid-phase microextraction (SPME) coating material for enrichment and determination of organic pollutants in water samples. Bamboo charcoal was prepared and used as a SPME coating material. Eleven phthalate esters (PAEs) were used as model analytes, and gas chromatography-mass spectrometry was used for separation and detection. Important extraction conditions (ionic strength, stirring rate, and extraction time) and desorption conditions (desorption temperature and time) were systematically investigated and optimized. Linearity of 0.1-100 µg L(-1) and correlation coefficients of 0.9992-0.9998 were obtained under optimum conditions. Inter-day and intra-day repeatability were 2.15-9.93 % and 1.89-9.85 %, respectively, and fiber-to-fiber reproducibility was 5.42-9.66 %. On the basis of a chromatographic signal-to-baseline noise ratio of three, the limits of detection reached 0.004-0.023 µg L(-1). Satisfactory results were achieved when the bamboo coating was used for determination of 11 PAEs in real water samples. The experimental results indicate that bamboo charcoal has significant potential as a SPME coating material for rapid enrichment and sensitive determination of organic pollutants in environmental samples.

12.
Zhonghua Nan Ke Xue ; 19(3): 236-40, 2013 Mar.
Artículo en Zh | MEDLINE | ID: mdl-23700730

RESUMEN

OBJECTIVE: To assess the efficacy and safety of the Osbon ErecAid Vacuum Therapy System in the treatment of erectile dysfunction (ED) that fails to respond to PDE-5i. METHODS: This study included 70 cases of ED not responding to the medication of PDE-5i. The patients were aged 25 -66 (38.9 +/- 9.1) years. Under our direction, the patients used the Osbon ErecAid Vacuum Therapy System for a month to increase blood oxygenation to the corpora cavernosa, and then employed the vacuum constriction device (VCD) to maintain penile erection for sexual intercourse. We compared their IIEF-5 scores and their and their partners' sexual satisfaction before and 3 months after treatment, and evaluated the safety and effect of the vacuum therapy. RESULTS: The mean IIEF-5 scores of the patients were significantly increased from 10.2 +/- 4.0 before treatment to 13.3 +/- 4.7 at 3 months after the vacuum therapy (P < 0.05). The rate of therapeutic effectiveness was 77.1% (54/70), and the rates of sexual satisfaction of the patients and their partners were 64.3% (45/70) and 65.7% (46/70), CONCLUSION: Vacuum therapy for ED that does not respond to PDE-5i can significantly improve the patients' erectile function as well as their and their partners'sexual satisfaction, and therefore deserves clinical application.


Asunto(s)
Disfunción Eréctil/terapia , Pene , Adulto , Anciano , Disfunción Eréctil/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Insuficiencia del Tratamiento , Resultado del Tratamiento , Vacio
13.
Int J Biol Sci ; 19(7): 2167-2197, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37151874

RESUMEN

So far there has been no comprehensive review using systematic literature search strategies to show the application of single-cell RNA sequencing (scRNA-seq) in the human testis of the whole life cycle (from embryos to aging males). Here, we summarized the application of scRNA-seq analyses on various human testicular biological samples. A systematic search was conducted in PubMed and Gene Expression Omnibus (GEO), focusing on English researches published after 2009. Articles related to GEO data-series were also retrieved in PubMed or BioRxiv. 81 full-length studies were finally included in the review. ScRNA-seq has been widely used on different human testicular samples with various library strategies, and new cell subtypes such as State 0 spermatogonial stem cells (SSC) and stage_a/b/c Sertoli cells (SC) were identified. For the development of normal testes, scRNA-seq-based evidence showed dynamic transcriptional changes of both germ cells and somatic cells from embryos to adults. And dysregulated metabolic signaling or hedgehog signaling were revealed by scRNA-seq in aged SC or Leydig cells (LC), respectively. For infertile males, scRNA-seq studies revealed profound changes of testes, such as the increased proportion of immature SC/LC of Klinefelter syndrome, the somatic immaturity and altered germline autophagy of patients with non-obstructive azoospermia, and the repressed differentiation of SSC in trans-females receiving testosterone inhibition therapy. Besides, the re-analyzing of public scRNA-seq data made further discoveries such as the potential vulnerability of testicular SARS-CoV-2 infection, and both evolutionary conservatism and divergence among species. ScRNA-seq analyses would unveil mechanisms of testes' development and changes so as to help developing novel treatments for male infertility.


Asunto(s)
COVID-19 , Infertilidad Masculina , Adulto , Humanos , Masculino , Anciano , Testículo/metabolismo , Espermatogénesis/genética , COVID-19/metabolismo , Proteínas Hedgehog/metabolismo , SARS-CoV-2/genética , Infertilidad Masculina/metabolismo , Análisis de Secuencia de ARN
14.
Cell Biosci ; 13(1): 94, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221631

RESUMEN

BACKGROUND: Spermatogenic dysfunction is an important cause of azoospermia. Numerous studies have focused on germ-cell-related genes that lead to spermatogenic impairment. However, based on the immune-privileged characteristics of the testis, the relationship of immune genes, immune cells or immune microenvironment with spermatogenic dysfunction has rarely been reported. RESULTS: Using integrated methods including single-cell RNA-seq, microarray data, clinical data analyses and histological/pathological staining, we found that testicular mast cell infiltration levels were significantly negatively related to spermatogenic function. We next identified a functional testicular immune biomarker, CCL2, and externally validated that testicular CCL2 was significantly upregulated in spermatogenic dysfunctional testes and was negatively correlated with Johnsen scores (JS) and testicular volumes. We also demonstrated that CCL2 levels showed a significant positive correlation with testicular mast cell infiltration levels. Moreover, we showed myoid cells and Leydig cells were two of the important sources of testicular CCL2 in spermatogenic dysfunction. Mechanistically, we drew a potential "myoid/Leydig cells-CCL2-ACKR1-endothelial cells-SELE-CD44-mast cells" network of somatic cell-cell communications in the testicular microenvironment, which might play roles in spermatogenic dysfunction. CONCLUSIONS: The present study revealed CCL2-relevant changes in the testicular immune microenvironment in spermatogenic dysfunction, providing new evidence for the role of immunological factors in azoospermia.

15.
Food Chem ; 404(Pt B): 134681, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36327505

RESUMEN

This study synthesized a conjugated microporous polymer (CMP) at room temperature, which has high surface area, large conjugate system, and nitrogen-rich features. The material was explored as a solid-phase extraction (SPE) column, and it showed a higher extraction efficiency for nitro-musks compared to most commercial columns. Under optimal SPE conditions, a sensitive and efficient method for determining five nitro-musks was established based on gas chromatography-mass spectrometry (GC-MS). The method showed excellent linearity (R2 ≥ 0.996), low limits of detection (0.13-0.57 ng·L-1), good repeatability (1.1-4.0 %, n = 6) and was applied to the detection of trace nitro-musks in water and milk samples. The mechanism was further discussed combined with a simulation calculation. The advantages of the proposed method were mainly reflected in the extraction efficiency and sensitivity, which also indicated the potential of CMPs as a sample pretreatment material.


Asunto(s)
Nitrógeno , Polímeros , Polímeros/química , Temperatura , Extracción en Fase Sólida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos
16.
J Agric Food Chem ; 71(22): 8656-8664, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37246392

RESUMEN

A magnetic molecularly imprinted polymer (MMIP) coupled nanospray ion source was developed for analysis of cephalosporin antibiotics in food samples. MIP coated Fe3O4 nanospheres were prepared for magnetic solid-phase extraction (MSPE) of the antibiotics in the extract of samples and then integrated into the nanospray capillary for further desorption and mass spectrometry analysis. The developed device combines the advantages of high extraction efficiency of MSPE, unique selectivity of MIPs, and fast analysis speed of ambient ionization mass spectrometry (AIMS). Five cephalosporin antibiotics in milk, egg, and beef samples were analyzed using the developed methods. High sensitivities with limits of detection (LODs) from 0.3 to 0.5 µg kg-1 were achieved for cephalosporin antibiotics in milk, egg, and beef samples, respectively. Good linearity, determination coefficient values (R2 > 0.992), and precision (RSD < 15%) with recoveries ranging from 72.6% to 115.5% were obtained using the spiked milk, egg, and beef sample matrices.


Asunto(s)
Cefalosporinas , Impresión Molecular , Animales , Bovinos , Cefalosporinas/análisis , Polímeros Impresos Molecularmente/análisis , Antibacterianos/análisis , Extracción en Fase Sólida/métodos , Fenómenos Magnéticos , Cromatografía Líquida de Alta Presión
17.
Analyst ; 137(22): 5411-9, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23042089

RESUMEN

In this paper, the potential applications of metal-organic framework (MOF) materials as fiber coatings for the solid-phase microextraction (SPME) of polycyclic aromatic hydrocarbons (PAHs) in water samples were explored. Fibers coated with MIL-53(Al, Cr, Fe) materials were fabricated by an adhesive method for SPME. The quantitation was performed by gas chromatography-tandem mass spectrometry (GC-MS/MS) using the multiple reaction monitoring mode. Among the three MIL-53(M) coatings, MIL-53(Al) showed the highest extraction efficiency towards PAHs under the current fabrication procedure. Under optimized conditions, the MIL-53(Al)-coated fiber showed good precision (relative standard deviation <12.5%), low detection limits (0.10 ng L(-1) to 0.73 ng L(-1), S/N = 3), and good linearity (R(2) > 0.98) for aqueous solutions containing 16 PAH . The fiber also offered high thermal and chemical stability. The method developed based on MIL-53(Al) SPME-GC-MS/MS was successfully applied in the analysis of real water samples. Based on the simulation results, the PAHs were adsorbed on MIL-53(Al) primarily through the hydrophobic and π-π interactions between PAHs and the organic linker of the material. The results presented in this paper indicate that water-stable MOF materials have great potential for the SPME of aromatic compounds in water samples.

18.
Anal Bioanal Chem ; 404(5): 1603-10, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22766759

RESUMEN

This paper demonstrates, for the first time, the great potential of using Zn/Al layered double hydroxide intercalated sodium dodecyl benzene sulfonate (Zn/Al-SDBS-LDH) as a solid-phase extraction (SPE) material in the extraction of persistent organic pollutants prior to the determination of gas chromatography-mass spectrometry in environmental water samples. Zn/Al-SDBS-LDH, a relatively inexpensive and simply prepared material, was synthesized and used as a SPE adsorbent to quantitatively determine the concentration of five polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Factors affecting extraction efficiency, such as, eluent type, eluent volume, flow rate of sample, sample volume, and amount of adsorbent, were investigated and optimized in detail. Experimental results indicate that there is an excellent linear relationship between peak area and the concentration of PAHs over the range of 5-500 ng L(-1), and the precisions (relative standard deviation (RSD)) were 2.5-6.3% under the optimum conditions. Based on the ratio of chromatographic signal-to-base line noise (S/N = 3), the limits of detection could reach 1.2-3.2 ng L(-1). This novel method was successfully applied to the analysis of PAHs in environmental water samples. As such, we show here that the use of Zn/Al-SDBS-LDH as SPE adsorbent materials, coupled with gas chromatography-mass spectrometry, is an excellent improvement in the routine analysis of PAHs at trace levels in the environment.

19.
Zhonghua Nan Ke Xue ; 18(5): 428-31, 2012 May.
Artículo en Zh | MEDLINE | ID: mdl-22741442

RESUMEN

OBJECTIVE: To explore the therapeutic effect of natural vitamin E (VitE) on oligospermia and asthenospermia in in- fertile men. METHODS: We conducted a prospective multi-centered randomized controlled study on 64 infertile men with oligospermia (31 as controls treated with Tamoxifen 10 mg bid and 33 as experimental cases treated with Tamoxifen 10 mg bid + VitE 100 mg tid) and 42 cases of asthenospermia (20 as controls treated with Levocarnitine oral solution 1 bottle bid and 22 as experimental cases treated with Levocarnitine oral solution 1 bottle bid + VitE 100 mg tid). We compared the control and experimental groups in sperm concentration and percentage of progressively motile sperm before and 3 months after medication, as well as the rate of clinical pregnancy and adverse events. RESULTS: Among the oligospermia patients, the average sperm concentrations in the control and experimental groups were 8.00 x 10(6)/ml and 10.66 x 10(6)/ml before medication (P > 0.05). After medication, the numbers of cases evaluated as with no, slight, moderate and marked improvement in sperm concentration were 10 and 9 (P > 0.05), 16 and 14 (P > 0.05), 5 and 4 (P > 0.05) and 0 and 0 (P >0.05); and the numbers of natural pregnancies were 0 and 6 in the control and experimental groups (P < 0.01). Among the asthenospermia patients, the average rates of progressively motile sperm were 17.00% and 18.10% in the control and experimental groups before medication (P > 0.05). After medication, the numbers of cases evaluated as with no, slight, moderate and marked improvement in the percentage of progressively motile sperm were 7 and 2 (P < 0.01), 4 and 8 (P < 0.01), 3 and 2 (P > 0.05) and 1 and 1 (P > 0.05), and the numbers of natural pregnancies were 5 and 9 in the two groups (P < 0.01), but no adverse events were observed. CONCLUSION: As a safe and effective adjuvant agent for the treatment of oligospermia and asthenospermia, vitamin E can improve sperm concentration, the percentage of progressively motile sperm, and finally the rate of natural pregnancy.


Asunto(s)
Astenozoospermia/tratamiento farmacológico , Oligospermia/tratamiento farmacológico , Vitamina E/uso terapéutico , Adulto , Carnitina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Índice de Embarazo , Estudios Prospectivos , Tamoxifeno/uso terapéutico , Resultado del Tratamiento , Adulto Joven
20.
Asian J Androl ; 24(3): 299-304, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34677147

RESUMEN

The extent of spermatogenic impairment on intracytoplasmic sperm injection (ICSI) outcomes and the risk of major birth defects have been little assessed. In this study, we evaluated the relationship between various spermatogenic conditions, sperm origin on ICSI outcomes, and major birth defects. A total of 934 infertile men attending the Center for Reproductive Medicine of Ren Ji Hospital (Shanghai, China) were classified into six groups: nonobstructive azoospermia (NOA; n = 84), extremely severe oligozoospermia (esOZ; n = 163), severe oligozoospermia (sOZ, n = 174), mild oligozoospermia (mOZ; n = 148), obstructive azoospermia (OAZ; n = 155), and normozoospermia (NZ; n = 210). Rates of fertilization, embryo cleavage, high-quality embryos, implantation, biochemical and clinical pregnancies, abortion, delivery, newborns, as well as major birth malformations, and other newborn outcomes were analyzed and compared among groups. The NOA group showed a statistically lower fertilization rate (68.2% vs esOZ 77.3%, sOZ 78.0%, mOZ 73.8%, OAZ 76.6%, and NZ 79.3%, all P < 0.05), but a significantly higher implantation rate (37.8%) than the groups esOZ (30.1%), sOZ (30.4%), mOZ (32.6%), and OAZ (31.0%) (all P < 0.05), which was similar to that of Group NZ (38.4%). However, there were no statistically significant differences in rates of embryo cleavage, high-quality embryos, biochemical and clinical pregnancies, abortions, deliveries, major birth malformations, and other newborn outcomes in the six groups. The results showed that NOA only negatively affects some embryological outcomes such as fertilization rate. There was no evidence of differences in other embryological and clinical outcomes with respect to sperm source or spermatogenic status. Spermatogenic failure and sperm origins do not impinge on the clinical outcomes in ICSI treatment.


Asunto(s)
Azoospermia , Oligospermia , Azoospermia/terapia , China , Femenino , Humanos , Recién Nacido , Masculino , Oligospermia/terapia , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Recuperación de la Esperma , Espermatogénesis , Espermatozoides
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