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.
Drug Delivery Systems ; instrumentation ; methods ; Endoscopes, Gastrointestinal ; classification ; Endoscopy, Gastrointestinal ; methods ; Humans ; Hydrogen-Ion Concentration ; Minimally Invasive Surgical Procedures ; instrumentation ; methods

BACKGROUNDA 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.

METHODSThis 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.

RESULTSThe 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.

CONCLUSIONSThe 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.

Adult ; Aminophylline ; administration & dosage ; pharmacokinetics ; Capsules ; administration & dosage ; pharmacokinetics ; Colon ; metabolism ; Humans ; Intestine, Small ; metabolism ; Male ; Young Adult

BACKGROUNDAtrial fibrillation (AF) is one of the most common arrhythmia after coronary artery bypass grafting (CABG), which not only increases the suffering of the patients, but also prolongs hospital stay and enhances cost of care, especially for patients older than 70 years. This study was designed to evaluate the efficacy and safety of low-dose amiodarone in the prevention of AF after CABG, especially for the elderly.

METHODSTwo hundred and ten senile patients undergoing off-pump CABG were included in this prospective, randomized, double-blind and placebo controlled study. Patients were given 10 mg/kg of amiodarone (low-dose amiodarone group, n = 100) or placebo (control group, n = 110) daily for 7 days before surgery and followed by 200 mg of amiodarone or placebo daily for 10 days postoperatively.

RESULTSPostoperative AF occurred in 16 patients (16%) receiving amiodarone and in 36 (37.7%) patients receiving placebo (P = 0.006). AF occurred at (58.13 +/- 16.63) hours after CABG in the low-dose amiodarone group and at (45.03 +/- 17.40) hours in the control group (P = 0.018). The maximum ventricular rate during AF was significantly slower in the low-dose amiodarone group ((121.42 +/- 28.91) beats/min) than in the control group ((134.11 +/- 30.57) beats/min, P = 0.036). The duration of AF was (10.92 +/- 9.56) hours for the low-dose amiodarone group compared with (14.81 +/- 10.37) hours for the control group (P = 0.002). The postoperative left ventricular ejection fraction (LVEF) was significantly improved in the low-dose amiodarone group (from (59.9 +/- 10.3)% to (63.4 +/- 11.4)%, P = 0.001), and significantly higher compared with the control group ((58.5 +/- 10.7)%, P = 0.002). Both groups had a similar incidence of complication other than rhythm disturbances (12.0% vs 16.4%, P = 0.368). The low-dose amiodarone group patients had shorter hospital stays ((11.8 +/- 3.2) days vs (13.8 +/- 4.7) days, P = 0.001) and lower cost of care (RMB (79 115 +/- 16 673) Yuan vs RMB (84 997 +/- 21 587) Yuan, P = 0.031) than that of control group patients. The in-hospital mortality was not significantly different between the two groups (1.0% vs 0.9%, P = 0.946).

CONCLUSIONSPerioperative low-dose oral amiodarone appeared to be cost-effective in the prevention and delay of new-onset postoperative AF in aged patients. It significantly reduced ventricular rate and duration of AF after CABG, decreased hospital cost and stay, as well as promoted the amelioration of left ventricular systolic function. Furthermore, low-dose amiodarone was safe to use and well tolerated with low toxic and side effects, and did not increase the risk of complications and mortality. It is proved to be a first-line therapy and as routine prophylaxis for AF after CABG, especially for elderly patients complicated with left ventricular dysfunction.

Aged ; Amiodarone ; administration & dosage ; Anti-Arrhythmia Agents ; administration & dosage ; Atrial Fibrillation ; etiology ; prevention & control ; Coronary Artery Bypass ; adverse effects ; Double-Blind Method ; Drug Administration Schedule ; Female ; Humans ; Male ; Treatment Outcome

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.
Capsule Endoscopes ; Equipment Design ; Wireless Technology