A non-invasive method for an in vivo assessment of corneal epithelium permeability through tetrapolar impedance measurements

Ischemic myocardial injury causes timed recruitment of neutrophils and monocyte/macrophages, which produce significant amounts of myeloperoxidase (MPO). MPO leads to the formation of reactive chlorinating species capable of oxidizing proteins. We developed a small molecule based MPO substrate for MRI, Gd-bis-5-HT-DPTA, which is first radicalized, and then oligomerized and covalently bound to matrix proteins, all leading to enhanced R1-relaxivity and delayed wash out kinetics. Mice were subjected to coronary artery ligation and injected with 0.3mmol/kg Gd-bis-5-HT-DPTA (or Gd-DTPA as control). We performed T1-weighted cardio-respiratory gated MRI 10–120min later, followed by immunoreactive staining for MPO. 3 mice each were studied at day 1, 2, 4, 8, and >1 month after MI. Subsequently, MPO tissue activity was determined with the guaiacol method. MPO activity peaked 2 days after MI (contrast-to-noise-ratio (CNR) day 1, 26+/−4; day 2, 39+/−10; day 4, 29+/−3), and tissue levels of MPO over time correlated well with probe activity in vivo (r2=0.65, p<0.01). CNR following Gd-DTPA peaked ten minutes after injection (10.5+/−0.2), and returned to pre-injection values at 60min. In contradistinction, following injection Gd-bis-5-HT-DPTA, CNR was higher and peaked later (p<0.05 vs. Gd-DTPA, arrows depict MI in figure ). Immunoreactive staining for MPO correlated well with enhancement (r2=0.92, p<0.05). Gd-bis-5-HT-DPTA facilitates in-vivo assessment of MPO activity in injured myocardium. This approach allows non-invasive probing of the inflammatory response to ischemia and has the potential to guide the development and application of novel cardioprotective therapies.

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Design of an Ingestible Capsule With Wireless Communication and Powering Function for Obesity Treating

Volume 10: Micro- and Nano-Systems Engineering and Packaging ◽

10.1115/imece2013-63599 ◽

2013 ◽

Author(s):

Liang Yan ◽

Tianyi Wang ◽

Zongxia Jiao ◽

Juanjuan Peng

Keyword(s):

Morbid Obesity ◽

Wireless Communication ◽

In Vitro Experiments ◽

Non Invasive ◽

Removal Process ◽

Wireless Control ◽

Invasive Method ◽

Energy Shortage

Intra-gastric balloons have been and effective and non-invasive method for morbid obesity treating since it is proposed. However, traditional balloons lead to complications such as nausea and sickness caused by insertion and removal endoscopes. Despite free of endoscope-guide insertion and removal process, wireless controlled balloons still have to face the problem of energy shortage. This paper proposes a novel wireless controlled and powered endoscope capsule of edible size. The performance of wireless control and powering are tested respectively. In addition, in-vivo and in-vitro experiments are conducted for further evaluation and shows feasibility for treating morbid obesity. This study may contribute to the development of endoscopic devices and surgery as well.

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A Non-Invasive Method For Measuring Platelet Aggregation In Vivo

10.1055/s-0038-1652351 ◽

1981 ◽

Author(s):

J Morley ◽

P M Hoyle ◽

J Leyton ◽

O J Davies

Keyword(s):

Graphical Form ◽

Functional Disturbance ◽

Non Invasive ◽

Hind Limbs ◽

Minute Period ◽

Invasive Method ◽

Crystal Scintillation ◽

Indium 111 ◽

Aggregation And Disaggregation

In experimental animals, intravenous injection of ADP produces platelet accumulation in the lungs, together with thrombocytopenia. Since platelets can be isotopically labelled without gross functional disturbance, we have sought to develop a method for measurement of aggregation and disaggregation of labelled platelets in vivo.Guinea-pig platelets are labelled with Indium-111 and injected into narcotised animals (Sagital, 37 mg/kg). Two collimated crystal scintillation probes are used to monitor the thoracic region (heart and lung) (Cl) and the vascular compartment (hind limbs) (C2). An indwelling cannula (25 SWG) is inserted into a foot vein and kept patent by small volumes of heparin (100 u/ml). Intravenous ADP (10 mg/kg) causes transient accumulation of platelets within the lung, as well as thrombocytopenia, within a two minute period. During a response, counts are monitored from both probes and retained in a dedicated microcomputer, so as to permit rapid display of results in tabular and graphical form. Usually, ninety consecutive 4 sec. counts are recorded, results being expressed both as a paired difference (C1-C2) and as a ratio (C1/C2). Repeated challenge can be made with ADP and a dose-related response is obtained over the range 10-30 mg/kg. Treatment with sulphinpyrazone or prostacyclin inhibits aggregation.

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