RESUMEN
According to the World Health Organization (WHO), 1.37 million people died of lung cancer all around the world in 2008, occupying the first place in all cancer-related deaths. However, this number might be decreased if patients were detected earlier and treated appropriately. Unfortunately, traditional imaging techniques are not sufficiently satisfactory for early detection of lung cancer because of limitations. As one alternative, breath volatile organic compounds (VOCs) may reflect the biochemical status of the body and provide clues to some diseases including lung cancer at early stage. Early detection of lung cancer based on breath analysis is becoming more and more valued because it is non-invasive, sensitive, inexpensive and simple. In this review article, we analyze the limitations of traditional imaging techniques in the early detection of lung cancer, illustrate possible mechanisms of the production of VOCs in cancerous cells, present evidence that supports the detection of such disease using breath analysis, and summarize the advances in the study of E-noses based on gas sensitive sensors. In conclusion, the analysis of breath VOCs is a better choice for the early detection of lung cancer compared to imaging techniques. We recommend a more comprehensive technique that integrates the analysis of VOCs and non-VOCs in breath. In addition, VOCs in urine may also be a trend in research on the early detection of lung cancer.
Asunto(s)
Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico , Compuestos Orgánicos Volátiles , Técnicas Biosensibles/métodos , Pruebas Respiratorias/métodos , Diagnóstico por Imagen/métodos , Nariz Electrónica , Humanos , Neoplasias Pulmonares/orina , Compuestos Orgánicos Volátiles/orinaRESUMEN
In clinical practice, examination of the hemorrhagic spot (HS) remains difficult. In this paper, we describe a remote controlled capsule (RCC) micro-system with an automated, color-based sensor to identify and localize the HS of the gastrointestinal (GI) tract. In vitro testing of the detecting sensor demonstrated that it was capable of discriminating mimetic intestinal fluid (MIF) with and without the hemoglobin (Hb) when the concentration of Hb in MIF was above 0.05 g/ml. Therefore, this RCC system is able to detect the relatively accurate location of the HS in the GI tract.
Asunto(s)
Hemorragia Gastrointestinal/diagnóstico , Sistemas Microelectromecánicos/instrumentación , Diseño de Equipo , HumanosRESUMEN
BACKGROUND: A patented remote controlled capsule (RCC) has recently been developed to provide noninvasive drug delivery to selected sites in the human gut that allows assessment of regional gastrointestinal (GI) drug absorption under a normal physiological environment. The objective of this study was to investigate the rate and extent of aminophylline absorption after site-specific delivery of the drug in the GI tract using RCC and a magnetic marker monitoring (MMM) technique. METHODS: This study was conducted in twelve healthy male subjects, in a three-treatment, randomized, crossover manner with a 7-day washout. Eligible subjects received a 150 mg aminophylline dose through an oral administration, or via a remote controlled capsule, delivered to the small bowel or ascending colon. MMM was employed to monitor the GI transit of the RCC, and the radio-frequency signal was used to activate capsules at target sites. Blood samples were obtained at regular intervals until 24 hours post dose/activation. Plasma theophylline concentrations were measured by a TDx System Analyzer. A comparison of the PK profile with the oral dosing route of aminophylline was performed after delivery to the small bowel and colon. RESULTS: The RCC was well tolerated in volunteers. The mean capsule activation time for the small bowel and ascending colon was 2.07 hours and 6.08 hours post dose. Aminophylline had similar absorption profiles from the small bowel compared with the stomach, with an area under the curve (AUC(t)) ratio of 92% vs. the stomach, but a lower absorption profile from the ascending colon, with an AUC(t) ratio of 47.2% vs. the stomach. CONCLUSIONS: The proprietary of the RCC and MMM technique offer the opportunity to obtain data on the intestinal absorption of a drug in humans under noninvasive conditions. Aminophylline is rapidly and efficiently absorbed from the small bowel. While colonic absorption was limited by the poor water condition although effective absorption was observed from the ascending colon. This provides an opportunity for rational development of modified-release formulations as well as alternative dosage forms.
Asunto(s)
Aminofilina/administración & dosificación , Aminofilina/farmacocinética , Cápsulas/administración & dosificación , Cápsulas/farmacocinética , Colon/metabolismo , Intestino Delgado/metabolismo , Adulto , Humanos , Masculino , Adulto JovenRESUMEN
The capsule-style micro-system is a hot spot of minimally-invasive medical instruments. Progresses of some typical capsule-style micro-systems, such as the wireless endoscope, site specific delivery capsule (SSDC), alimentary tract sampling capsule, PH capsule, etc. are introduced here in detail. The research activities in China and the developing trend of capsule-style micro-systems are discussed too.
Asunto(s)
Endoscopios Gastrointestinales , Endoscopía Gastrointestinal/métodos , Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/métodos , Endoscopios Gastrointestinales/clasificación , Humanos , Concentración de Iones de Hidrógeno , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodosRESUMEN
The swallowable camera-capsule,described in the aper, 11 mm in diameter and 30 mm in length , contains a CMOS image sensor, an optical system, a battery, a light source, a transmitter, a antenna and so on. The CMOS image sensor and its driving circuit can be miniaturized with MEMS technology. Image signal can be transmitted by analog or digital way. Image signal can be wirelessly transmitted through serial data interface. Finally, the processing technics of the capsule's crust is introduced.