RESUMEN
Modern Lab-on-a-chip (LOC) platforms for genomic applications integrate several biological tasks in a single device. Combination of these processes into a single device minimizes sample loss and contamination problems as well as reducing analysis time and costs. Here we present a study of a microchip platform aimed at analyzing issues arising from the combination of different functions, such as DNA purification from blood, target amplification by PCR and DNA detection in a single silicon-based device. DNA purification is realized through two different strategies: 1) amine groups coating microchannel surfaces and 2) magnetic nanoparticles coated by chitosan. In the first strategy silicon/Pyrex microdevices coated with 3-aminopropyltriethoxysilane (APTES) or 3-2-(2-aminoethylamino)-ethylamino]-propyltrimethoxysilane (AEEA) were examined and their efficiency in human genomic DNA adsorption/desorption was evaluated. APTES treatment was the most suitable for the purification of a reasonable amount of DNA in a state suitable for the following PCR step. The second strategy has instead the main advantage of avoiding an elution step, since the DNA adsorbed on the magnetic nanoparticles can be used as PCR template. On-chip PCR was performed in a custom thermocycler, while the detection of PCR products was carried out by fluorescence reading. A complete genetic analysis was demonstrated on the monolithic silicon/Pyrex microchip, starting from less than 1 [Formula: see text]L of human whole blood and arriving at SNPs identification. The successful integration of DNA purification, amplification and detection on a single microdevice was proven without the need for biological passivation steps and possibly simplifying the realization of genomic detection devices.
Asunto(s)
ADN/aislamiento & purificación , Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Silicio/química , Quitosano/química , Diseño de Equipo/instrumentación , Eritrocitos/química , Eritrocitos/citología , Genoma Humano , Humanos , Nanopartículas/química , Reacción en Cadena de la Polimerasa/instrumentación , Reacción en Cadena de la Polimerasa/métodos , Propilaminas , Silanos/metabolismoRESUMEN
With the development of contact sidefiring fibers, urologists have gained a valuable tool to deliver laser energy more precisely into prostatic tissue. Contact laser prostatectomy can now be viewed as a well-established procedure that offers several distinct advantages over conventional methods such as transurethral resection of the prostate. The results of experimental and clinical studies are presented, supporting the value of this new modality.
Asunto(s)
Cistoscopios , Terapia por Láser/métodos , Prostatectomía/métodos , Animales , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Tecnología de Fibra Óptica , Humanos , Terapia por Láser/instrumentación , Masculino , Prostatectomía/instrumentaciónRESUMEN
The appeal of laser therapy is rooted in its absence of complications relative to the gold standard of transurethral electroresection. As in any evaluation of a new medical intervention, efficacy must be weighed against the degree of complications that accompany it. Although there has been a relative paucity of literature specifically addressing the safety of this new modality, several studies are presented testifying to the clinical efficacy and relative absence of complications of laser prostatectomy.
Asunto(s)
Terapia por Láser/efectos adversos , Prostatectomía/efectos adversos , Hiperplasia Prostática/cirugía , Humanos , Masculino , Complicaciones Posoperatorias , Prostatectomía/métodosRESUMEN
Butorphanol/diazepam was compared with thiopental for induction of anesthesia, and the thiopental-sparing effects of butorphanol/diazepam determined. One hundred women, American Society of Anesthesiology physical status class I, undergoing ambulatory, elective termination of pregnancy were randomized to receive either butorphanol 2 mg plus diazepam 10 mg, or thiopental, until loss of the lid reflex occurred. The butorphanol/diazepam group received supplemental thiopental as necessary to attain adequate induction of anesthesia. The combination of butorphanol and diazepam significantly reduced the thiopental dose required to produce loss of the lid reflex, from 4.2 +/- 0.8 to 0.8 +/- 0.6 mg/kg (p less than 0.005), with 22 percent of the patients not requiring supplemental thiopental. The intraoperative course and anesthetic requirements were similar between the two groups. Lower recovery room rating scale values upon arrival at the recovery room were attributed to significantly higher weight-normalized doses of butorphanol (p = 0.004) and diazepam (p = 0.005). The duration of the recovery room stay was 68.8 +/- 24.9 min for the control group, and 80.8 +/- 29.0 min for the butorphanol/diazepam-treated patients (p = 0.026). There were no clinically significant differences in anesthesia or postanesthesia recovery. The combination of butorphanol and diazepam has a significant thiopental-sparing effect, and is a useful induction technique for short, ambulatory surgical procedures.