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2.
Langmuir ; 29(2): 667-72, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23268689

RESUMEN

Emulsifier-free emulsion polymerization was employed to synthesize polystyrene (PS) microspheres, which were then self-assembled into an ordered periodic structure. A photochromic film was formed by adding polydimethylsiloxane (PDMS) around the self-assembly of PS microspheres on a PDMS substrate. During polymerization, the PS microspheres shrunk depending on the amount of the hydrophilic comonomer, sodium 4-styrenesulfonate (NaSS). Variation in structural color was strongly affected by the size of the PS microspheres. Scanning electron microscopy was used to observe the surface and cross sections of the self-assembled microspheres. Results showed that the order and stacking thickness of microspheres were dependent on the drawing rate of the substrate and suspension concentration. High-transmittance photochromic films could be prepared when the drawing rate was lower than 1 µm/s and the suspension concentration was 20 wt %. PDMS surrounding the vacant space between regularly arranged PS microspheres could not only protect them but also increase the degree of matching between the refractive indices of PS and PDMS. The stability of the reflected structural color increased, and the optical transmittance of the photochromic film approached 95% after PDMS was poured between the PS microspheres. A special pattern could be designed and embedded inside the photochromic film. The PS/PDMS photochromic films can also be applied in decorative painting as well as in security devices, color-changing false nails, and privacy filters.


Asunto(s)
Materiales Biomiméticos/química , Dimetilpolisiloxanos/química , Poliestirenos/química , Color , Interacciones Hidrofóbicas e Hidrofílicas , Luz , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Microesferas , Propiedades de Superficie
3.
J Virol Methods ; 151(2): 298-300, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18571737

RESUMEN

The impact of 6-month storage of cervical specimens under alkaline conditions that occurs as the result of Hybrid Capture 2 testing on human papillomavirus (HPV) genotyping is not well documented. To examine this issue, 143 frozen hc2-positive specimens in specimen transport medium were selected at random from each of the following groups: specimens stored for 6 months, 4 months, and 2.5 months under alkaline pH (pH 12-13) and specimens stored 1 month at neutral pH (pH 6-7) as controls. Specimens were tested in a masked fashion for 20 HPV genotypes (HPV6, 11, 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 73, and 82) using a prototype, research-use-only GP5+/6+ L1 consensus PCR method and multiplex hybridization using Luminex xMAP for detection of specific HPV genotypes One control specimen had missing test results. There were no statistical differences in the number of HPV genotypes detected, number of carcinogenic HPV genotypes detected, or in the signal strength among HPV-positive results across groups. Six-month frozen storage of cervical specimens at alkaline pH had little impact on testing for HPV genotypes among hc2-positive women using this HPV genotyping method.


Asunto(s)
Alphapapillomavirus/genética , Cuello del Útero/virología , Infecciones por Papillomavirus/diagnóstico , Alphapapillomavirus/aislamiento & purificación , Femenino , Congelación , Genotipo , Humanos , Concentración de Iones de Hidrógeno , Manejo de Especímenes/métodos
4.
J Clin Microbiol ; 46(6): 1901-6, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18400913

RESUMEN

Hepatitis C virus (HCV) genotyping is a tool used to optimize antiviral treatment regimens. The newly developed Versant HCV genotype assay (LiPA) 2.0 uses sequence information from both the 5' untranslated region and the core region, allowing distinction between HCV genotype 1 and subtypes c to l of genotype 6 and between subtypes a and b of genotype 1. HCV-positive samples were genotyped manually using the Versant HCV genotype assay (LiPA) 2.0 system according to the manufacturer's instructions. For the comparison study, Versant HCV genotype assay (LiPA) 1.0 was used. In this study, 99.7% of the samples could be amplified, the genotype of 96.0% of samples could be determined, and the agreement with the reference method was 99.4% when a genotype was determined. The reproducibility study showed no significant differences in performance across sites (P = 0.43) or across lots (P = 0.88). In the comparison study, 13 samples that were uninterpretable or incorrectly genotyped with Versant HCV genotype assay (LiPA) 1.0 were correctly genotyped by Versant HCV genotype assay (LiPA) 2.0. Versant HCV genotype assay (LiPA) 2.0 is a sensitive, accurate, and reliable assay for HCV genotyping. The inclusion of the core region probes in Versant HCV genotype assay (LiPA) 2.0 results in a genotyping success rate higher than that of the current Versant HCV genotype assay (LiPA) 1.0.


Asunto(s)
Hepacivirus/clasificación , Hepacivirus/genética , Hibridación de Ácido Nucleico/métodos , Juego de Reactivos para Diagnóstico , Regiones no Traducidas 5'/genética , Genotipo , Hepatitis C/virología , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Factores de Tiempo , Proteínas del Núcleo Viral/genética
6.
J Virol Methods ; 146(1-2): 80-5, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17673302

RESUMEN

Human papillomavirus (HPV) genotyping could be clinically useful, depending on the results of large, prospective studies like the HPV persistence and progression (PaP) cohort. The cohort is based on genotyping and follow-up of Hybrid Capture-positive women at Kaiser Permanente, Northern California. HPV DNA testing by Hybrid Capture 2 requires denaturation with alkali, possibly damaging the DNA for optimal PCR-based genotyping. A feasibility study was conducted on paired aliquots of anonymized specimens from 100 women with low-grade intraepithelial lesion cytology. Test aliquots were left in denaturant for 10 or 18h at 4 degrees C and then neutralized; comparison aliquots were not denatured but diluted to match the timing, temperature, concentration and salt conditions of the treated specimens. The masked aliquots were tested using a commercialized PCR-based assay that detects of 37 HPV genotypes. There was no overall effect of treatment on test positivity or number of types. HPV16 was marginally more likely to be detected in untreated versus treated aliquots (P=0.09) but HPV45 was marginally more likely to be detected in treated than untreated aliquots (P=0.07), suggesting that these differences represented chance (intra-test variability). It can be concluded that residual Hybrid Capture-positive specimens can be genotyped by PCR after Hybrid Capture 2 processing.


Asunto(s)
Cuello del Útero/virología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa/métodos , Enfermedades del Cuello del Útero/virología , Displasia del Cuello del Útero/virología , Estudios de Cohortes , Femenino , Genotipo , Humanos , Papillomaviridae/clasificación , Papillomaviridae/genética , Neoplasias del Cuello Uterino/virología
7.
Arch Phys Med Rehabil ; 86(9): 1884-6, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16181959

RESUMEN

Anejaculation and poor semen quality are 2 major causes of infertility in men with spinal cord injury (SCI). The low motility of retrieved sperm often results in use of intracytoplasmic sperm injection (ICSI) to achieve fertilization. Pregnancy is a challenging event for women with SCI. Herein we report a pregnancy after ICSI with cryopreserved electroejaculate sperm for a couple both with SCI. The husband had T10 paraplegia with a neurogenic bladder. He underwent 2 electroejaculations. The concentration of sperm was 0.1 x 10(6)/mL to 0.3 x 10(6)/mL, with a motility of 5% to 20%. ICSI was considered the best choice for the couple. His wife had L2 paraplegia with cauda equina syndrome. She underwent controlled ovarian hyperstimulation, and 10 oocytes were retrieved. Eight mature oocytes were injected using thawed sperm, which resulted in 5 normal zygotes. Conception was achieved by the transfer of 4 embryos into the uterus. A healthy female baby was delivered vaginally at 39 weeks of gestation. This woman had never undergone any other assisted reproductive technology (ART) procedures. With the advancement of ART and prenatal care, this couple achieved a successful pregnancy. The use of cryopreserved electroejaculated sperm for ICSI can avoid the inconvenience or cost to the patient of repeated electroejaculations.


Asunto(s)
Criopreservación , Resultado del Embarazo , Embarazo/fisiología , Preservación de Semen/métodos , Inyecciones de Esperma Intracitoplasmáticas , Traumatismos de la Médula Espinal/complicaciones , Adulto , Eyaculación/fisiología , Estimulación Eléctrica/métodos , Femenino , Humanos , Masculino , Vértebras Torácicas , Resultado del Tratamiento
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