RESUMEN

Single nucleotide polymorphism (SNP) was associated with many human diseases, therefore, SNP detection was important for early diagnosis and clinical prognosis. Herein, a simple and accurate method for visual detection SNP sites (A/A, G/G, A/G) in CYP1A1 gene related to cancers based on colloidal gold nucleic acid strip biosensor and primer-specific polymerase chain reaction (PCR) was established. This method could directly distinguish SNP sites on strip biosensor by introducing twice PCR amplifications. The second PCR (primer-specific PCR) was performed using specific product of the first PCR as template, thus this twice PCR could reduce non-specific amplification greatly and obtain target product. In addition, single-strand or double-strand DNA (ssDNA or dsDNA) was accurately produced by introducing mismatched base at the 3' end of forward primers in primer-specific PCR. The designed strip biosensor could only combine with the ssDNA, thus visual detection of SNP could be achieved within 10 min by color difference of a pair of strips. 61 human blood samples by this method were identical with those of pyrosequencing. This method had the advantages of rapid, visual and low-cost and was expected to be applied in medical diagnosis.

Asunto(s)

Técnicas Biosensibles/métodos , Citocromo P-450 CYP1A1/genética , ADN/sangre , Oro Coloide/química , Polimorfismo de Nucleótido Simple , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Colorimetría/métodos , ADN/genética , Sondas de ADN/química , Oro/química , Humanos , Nanopartículas del Metal/química , Reacción en Cadena de la Polimerasa/métodos

RESUMEN

Despite burgeoning development of nanoplatform made in the past few years, it remains a challenge to produce drug nanocarrier that enables requested on/off drug release. Thus, this study aimed to develop an ideal near-infrared light-triggered smart nanocarrier for targeted imaging-guided treatment of cancer that tactfully integrated photothermal therapy with chemotherapy to accurately control drug release time and dosage. Methods: This delivery system was composed of Ag2S QD coating with dendritic mesoporous silica (DMSN), which acted as nanocarrier of doxorubicin localized inside pores. To provide the nanocarrier with controlled release capability, a polypeptide-engineered that structure was reversible to photothermal effect of Ag2S QD, was covalently grafted to the external surface of drug-loaded DMSN. Results: This nanocarrier with the size of 40~60 nm had satisfactory biocompatibility and photothermal conversion efficiency up to 28.35%. Due to acidity-triggered charge reversal of polypeptide, which significantly extended circulation time and improved targeting ability, fluorescence and photoacoustic signals were still obvious at tumor site post-24 h by tail vein injection and chemo-photothermal synergistic therapy obviously enhanced antitumor efficacy. Mild PTT with multiple short-term exposures not only reduced the side effect of overdose drug but also avoided skin damage caused by long-term irradiation. Conclusion: By adjusting irradiation time and on/off cycle, multiple small amount local drug release reduced the side effect of overdose drug and skin damage. This novel approach provided an ideal near-infrared light-triggered nanocarrier with accurate control of area, time, and especially dosage.

Asunto(s)

Portadores de Fármacos/química , Nanopartículas/química , Péptidos/química , Animales , Línea Celular Tumoral , Terapia Combinada/métodos , Doxorrubicina/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de los fármacos , Fluorescencia , Células HeLa , Humanos , Rayos Infrarrojos , Células MCF-7 , Ratones , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Dióxido de Silicio/química

RESUMEN

Objective@#To explore associated factors of mobile phone dependence and its relation with psychological resilience among college students.@*Methods@#College students from 5 universities in Hefei were randomly selected through multi-stage sampling (stratified clustering) and investigated with questionnaires. A total of 2 502 college students were included in the analysis.@*Results@#Mobile phone dependence among college students differed by gender (χ2=18.25, P<0.01), residence (χ2=17.71, P<0.01), whether in a relationship(χ2=8.09, P<0.01), grade(χ2=19.58, P<0.01), only child(χ2=7.48, P<0.01), family economic status (χ2=17.43, P<0.01) and time spent in mobile phone (χ2=73.46，P<0.01) while no similar differences were found by family structure and length of mobile phone ownership. Spearman correlation showed negative correlation (P<0.01) between mobile phone dependence and psychological resilience. Logistic regression model results showed that female, not in a relationship, lower grade, less time spent in mobile phone and high psychological resilience were negatively correlated with mobile phone dependence. Compared with students from rural areas, urban area was positively associated with mobile phone dependence. Emotional control, family support, and interpersonal assistance associated with lower risk for mobile phone dependence.@*Conclusion@#Mobile phone dependence is affected by gender, relationship status, grade, usage duration, and residence. High psychological resilience associated negatively with risk for mobile phone dependence.