Cyberdyne and EKSO’s Bionic Skeleton

Cyberdyne, a Japanese company, received CE mark for it’s HAL (hybrid assistive limb) for rehab use. It is designed to help people with lower-body disability to walk. The current model is for rehab use only, not to be taken home for daily use.

Similarly, an American company called EKSO Bionics has developed a bionic suit to enable individuals with various levels of paralysis to hemiparesis to stand up and walk.

The skeleton suit has multiple walk modes to actuates steps with a button, to steps via user control, to achieve next step by moving hips, or to step by user’s weight shift..

Circulating Tumor Cells

What is circulating tumor cells?

Circulating tumor cells are the lurking foes shed from primary tumor mess into a cancer patient's circulation systems, including blood and lymphatic systems.  circulating tumor cells (CTCs) are rare. How rare? In a metastatic cancer patient, typically it’s only 1 CTC per billions of red blood cells, or a single digit per 10 ml of blood. However, the rare CTCs act like dangerous seeds, lurking in the circulation and seeking new sites to lodge and grow. The tumor transfer to remote organs is called metastasis. 

Shocking Facts

 Metastatic carcinoma is the main cause of death in cancer patients. And the metastases are taking place via circulating tumor cells. In advanced colorectal cancer, patients with a CTC count >3 per 7.5ml blood had a worse therapeutic outcome [1]. In breast cancer, patients had CTC count of >5 per 7.5ml blood had significant shorter median survival (6.7 months) and overall survival (13.2 months). A study published in New England Journal of Medicine even revealed that the progression-free survival is only 2.7 months for patients who had CTC count >5 [2]. 

A Little More to Know

The only FDA approved CTC counting method is CellSearch (https://www.cellsearchctc.com/) CTC test. CellSearch system use magnetic beads coated with anti-EpCAM antibodies to target CTCS for enrichment and with immune-fluorescence labeling for identifying and counting. There is no approved method or drug to specifically kill CTCs inside human body.

The CELLSEARCH® System is the result of a commitment to innovation that began in 1999 and led to the first standardized, FDA-cleared, semi-automatic system that can capture and quantify circulating tumor cells from a 7.5-mL blood sample with a high level of sensitivity and specificity (adapted from CELLSEARCH website).

Current research work focuses on capturing, enumerating, and characterizing CTCs in blood samples [4]. The most commonly way to capture CTCs relies on the antibody that binds to surface protein. Through immune-labeling with either magnetic or fluorescence tags, CTCs can be isolated for imaging and analysis to recognize its molecular signature.

CTCs are seeding cells originated from primary tumor mass. Current research efforts on CTCs focus on methods of capturing, isolating, and identifying the cells for the purpose of diagnosis and characterization of phenotype signature. Lodging of the rare lurking foes results in the metastases of a tumor to remote organs and leads to fatal consequences. However, it’s still very hard to effectively find and capture the dangerous seeds. The figure shows a brief of recent research work [3].  

Another brief review of capturing cancer cells reported in The Scientist in April 2014 can be found at: http://www.the-scientist.com/?articles.view/articleNo/39503/title/Capturing-Cancer-Cells-on-the-Move/

Citations

[1] J Clin Oncol 26:3213-3221, 2008

[2] N Engl J Med 351; 8 781-791, 2004

[3] Science Vol.327, 26 Feb., 2010

[4] D. R. Parkinson et al., Considerations in the development of circulating tumor cell technology for clinical use. J Translational Medicin 10:138, 2012. 

Intuitive Surgical Released Their New Robotic Surgical System, da Vinci Xi.

On April 1^st (hope this is not a joke), 2014, Intuitive Surgical announce their new da Vinci Xi surgical system, which is a robotic surgical system intended for minimal invasive surgeries in gynecology, urology, thoracic, cardiac, and general surgery. The company was once elected as one of the 5 worst performing medical device firms of 2013, mainly because of their lawsuits regarding the induced injuries and casualties with the use of the system. Now the company is seeking a better year in 2014 with the new robot system. Even though the first quarter of 2014 didn't show a strong rebound on sales, the imperative robotic surgical technique rendered by Intuitive Surgical will push the use of robots in surgical suite an inevitable solution to provide a better quality of patient's life. 

More reading at: http://www.intuitivesurgical.com/

A Confocal Endoscope for Medical Use

A new confocal endoscope from MGH (Tearney’s group) published in Biomedical Optics Express (V4 No10, 2013, doi: 10.1364/BOE.4.001925). Over 5 decades after Marcin Minsky, a Harvard scientist, invented confocal microscopy, the imaging technology has been delivered through catheters for minimally invasive interrogation. Confocal endoscope has been applied in gastrointestinal and colonoscopic imaging. A traditional confocal scanning probe can provide fluorescence images through a work channel of a colonoscope, for example, and provide clear imaging with the aid of water and air jets from the scope, such as a Pentax EC-3870CIFK colonoscope.

This work published in Biomedical Optics Express adapted a method termed spectrally encoded confocal microscopy (SECM). The SECM diffracts each wavelength into one-to-one point via a grating, and thus form a 1-D spectrally encoded image. The line image is formed stationally to increase imaging speed and imaging stability without the use of a scanning motion. The result of the image is a reflectance image instead of fluorescence image.

In this publication, it is demonstrated in the application of Barrett’s esophagus, a precursor of esophageal adenocarcinoma, which is a rare but particularly deadly form of cancer.   

A schematic of spectrally encoded confocal microscopy (SECM) probe optics and system (CL = collimation lens, and BS = beamsplitter). SECM is being developed for possible clinical applications. Courtesy of DongKyun Kang et al (2013), ‘Endoscopic probe optics for spectrally encoded confocal microscopy.’

Swallowable Tethered Capsule OCT Endomicroscopy

Targeting Barrett’s esophagus and gastrointestinal (GI) tract diagnosis, Dr. Gary Tearney and Michalina Gora and their colleagues from Wellman Center for Photomedicine at MGH have developed a wired capsule imager to screen a patent’s esophagus. OCT has been proved to be effective on imaging esophageal carcinoma. The device involves optical frequency domain OCT technology — a rapidly rotating laser tip emitting a beam of near-infrared light and sensors that record light reflected back from the esophageal lining.

The device provides painless (if their report is true), well-tolerated, accurate, and inexpensive method for screening and monitoring of disease progression in the upper gastrointestinal tract. To date, they have performed trials on 40 patients, imaging esophageal disorders and the first portion of small intestine (duodenum) to show the application for diagnosis. Multiple journal papers have been published in 2013 and 2014 about the progress and applications of this technology.  

By manipulating the plastic ball attached to the flexible tether (lower, right hand) the system operator can control the position of the endomicroscopy capsule in a patient’s esophagus (credit: Michalina Gora, PhD and Kevin Gallagher/Wellman Center for Photomedicine, Massachusetts General Hospital)

Tethered capsule endomicroscopy. (a) Overview of the tethered capsule endomicroscopy device. (b) Expanded schematic of the capsule. (Credit: Michalina Gora, PhD and Kevin Gallagher/Wellman Center for Photomedicine, Massachusetts General Hospital)

More reading material regarding this work:

Journal paper: Imaging the Upper Gastrointestinal Tract in Unsedated Patients Using Tethered Capsule Endomicroscopy, Gastroenterology. Vol.145(4), 2013. Tethered capsule endomicroscopy enables less invasive imaging of gastrointestinal tract microstructure, Nature Medicine, Vol.19(2), 2013.

News when it first came out:  http://scitechdaily.com/ingestible-pill-sized-imaging-system-provides-3d-view-of-the-esophageal-wall/