Challenges in the noninvasive detection of body composition using near-infrared spectroscopy

Noninvasive detection of body composition plays a significant role in the improvement of life quality and reduction in complications of the patients,and the near-infrared(NIR)spectroscopy,with the advantages of painlessness and convenience,is considered as the most promising tool for the online noninvasive monitoring of body composition.However,quite different from other fields of online detection using NIR spectroscopy,such as food safety and environment monitoring,noninvasive detection of body composit ion demands higher precision of the instruments as well as more rigor-ousness of measurement conditions.Therefore,new challenges emerge when NIR spectroscopy is applied to the noninvasive detection of body composition,which,in this paper,are first concluded from the aspects of measurement methods,measurement conditions,instrument precision,multi-component influence,individual difference and novel weak signal extraction method based on our previous research in the cutting edge field of NIR noninvasive blood glucose detection.Moreover,novel ideas and approaches of our group to solve these problems are introduced,which may provide evidence for the future development of noninvasive blood glucose detection,and further contibute to the noninvasive detection of other body compositions using NIR spectroscopy.

Noninvasive Detection and Imaging of Matrix Metalloproteinases for Cancer Diagnosis

Matrix metalloproteinases(MMPs)are important cancer biomarkers and the sensitive detection of MMPs is of great importance to improve clinical diagnosis and therapy of cancer at its early stage.Molecular imaging,including fluorescent optical imaging,radiolabeled imaging,and magnetic resonance imaging,is a powerful tool to visualize and characterize biological processes at the cellular and molecular level.The recognition of MMPs via imaging strategies by utilizing MMP-responsive probes has been a hot pursuit in recent years.Probes designed for MMP detection commonly have two features:(1)off-thenon state in detection signal response to the appearance of MMPs,which has been applied in optical imaging and magnetic resonance imaging;(2)specific retention upon sensing MMPs,which has been applied in radiolabeled imaging.The development of theory and technology in the field of biomarker probes will be beneficial to the accurate diagnosis and effective treatment of cancer.

Adaptive deep learning for head and neck cancer detection using hyperspectral imaging

It can be challenging to detect tumor margins during surgery for complete resection.The purpose of this work is to develop a novel learning method that learns the difference between the tumor and benign tissue adaptively for cancer detection on hyperspectral images in an animal model.Specifically,an auto-encoder network is trained based on the wavelength bands on hyperspectral images to extract the deep information to create a pixel-wise prediction of cancerous and benign pixel.According to the output hypothesis of each pixel,the misclassified pixels would be reclassified in the right prediction direction based on their adaptive weights.The auto-encoder network is again trained based on these updated pixels.The learner can adaptively improve the ability to identify the cancer and benign tissue by focusing on the misclassified pixels,and thus can improve the detection performance.The adaptive deep learning method highlighting the tumor region proved to be accurate in detecting the tumor boundary on hyperspectral images and achieved a sensitivity of 92.32%and a specificity of 91.31%in our animal experiments.This adaptive learning method on hyperspectral imaging has the potential to provide a noninvasive tool for tumor detection,especially,for the tumor whose margin is indistinct and irregular.

Noninvasive Surface Detection of Papillary Thyroid Carcinoma by Fourier Transform Infrared Spectroscopy

Previously Fourier transform infrared（FTIR） spectroscopy has been applied to detecting thyroid cancer during operations and to discriminating cervical metastatic ones from non-metastatic lymph nodes. This study explored the possibility of establishing a sensitive, accurate and noninvasive screen or diagnosis by preoperative FTIR spectroscopy. 111 patients undergone a thyroid operation and 50 healthy volunteers were enrolled in the study. The FTIR spectra were obtained by two mid-infrared optical fibers with an attenuated total reflectance（ATR） probe closely contacting the subjects＇ skin on the thyroid nodules. The FTIR spectra obtained from normal thyroid, nodular goiter（NG） and papillary thyroid carcinoma（PTC） patients were compared. A Fisher＇s discriminant analysis was created based on these data. There were 41 PTC patients and 70 NG patients according to their histopathological examinations. A total of 23（of 39） parameters were statistically different among the three groups（P〈0.05）. The Fi300 and F1080 parameters were significantly different between the three groups. In total, 9 out of 39 FTIR parameters were selected as independent factors by the Wilks＇ lambda stepwise discriminant analysis. The discrimination accuracy of papillary thyroid carcinoma in the three groups was 88.8%. Surface detection of PTC by FTIR spectroscopy is feasible. FTIR spectroscopy can be used for rapid and noninvasive PTC screen and auxiliary diagnosis.

Noninvasive blood glucose detection using a miniature wearable Raman spectroscopy system

Nowadays, there are about 415 million adults suffering from diabetesN. At present, the treatment for diabetes patients is monitoring their blood glucose level frequently and then taking the appropriate amount of oral hypogly- cemic drugs and insulin to control their blood glucose level.

Sensing nanomaterials of wearable glucose sensors

The metabolic disorder of glucose in human body will cause diseases such as diabetes and hyperglycemia.Hence the determination of glucose content is very important in clinic diagnosing.In recent years,researchers have proposed various non-invasive wearable sensors for rapid and real-time glucose monitoring from human body fluids.Unlike those reviews which discussed performances,detection environments or substrates of the wearable glucose sensor,this review focuses on the sensing nanomaterials since they are the key elements of most wearable glucose sensors.The sensing nanomaterials such as carbon,metals,and conductive polymers are summarized in detail.And also the structural characteristics of different sensing nanomaterials and the corresponding wearable glucose sensors are highlighted.Finally,we prospect the future development requirements of sensing nanomaterials for wearable glucose sensors.This review would give some insights to the further development of wearable glucose sensors and the modern medical treatment.

Multispectral light scattering endoscopic imaging of esophageal precancer

Esophageal adenocarcinoma is the most rapidly growing cancer in America.Although the prognosis after diagnosis is unfavorable,the chance of a successful outcome increases tremendously if detected early while the lesion is still dysplastic.Unfortunately,the present standard-of-care,endoscopic surveillance,has major limitations,since dysplasia is invisible,often focal,and systematic biopsies typically sample less than one percent of the esophageal lining and therefore easily miss malignancies.To solve this problem we developed a multispectral light scattering endoscopic imaging system.It surveys the entire esophageal lining and accurately detects subcellular dysplastic changes.The system combines light scattering spectroscopy,which detects and identifies invisible dysplastic sites by analyzing light scattered from epithelial cells,with rapid scanning of the entire esophageal lining using a collimated broadband light beam delivered by an endoscopically compatible fiber optic probe.Here we report the results of the first comprehensive multispectral imaging study,conducted as part of routine endoscopic procedures performed on patients with suspected dysplasia.In a double-blind study that characterized the system’s ability to serve as a screening tool,55 out of 57 patients were diagnosed correctly.In addition,a smaller double-blind comparison of the multispectral data in 24 patients with subsequent pathology at locations where 411 biopsies were collected yielded an accuracy of 90%in detecting individual locations of dysplasia,demonstrating the capability of this method to serve as a guide for biopsy.