Search

Chronic liver diseases progressively lead to cirrhosis, liver failure, and other complications. Fourier Transform Infrared (FTIR) spectroscopy and microspectroscopy imaging are rapidly advancing techniques with multiple benefits for early diagnosis, grading, and monitoring of a broad spectrum of liver diseases. FTIR provides a biochemical overview of a sample, which can be used to determine the need for further in-depth investigations. Numerous studies have showed that infrared imaging offers a great promise for understanding of disease pathogenesis compared to that of common histopathological investigations. Moreover, high-throughput infrared characterization of biofluids has attracted increased interests for a wide array of pathologic diagnosis. The use of infrared spectroscopy and microspectroscopy for diagnosis, grading, and monitoring of liver diseases requires an understanding of infrared microspectroscopy, sample preparation, data collection, analysis, and interpretation. This review provides a comprehensive and up-to-date review of FTIR spectroscopy and microspectroscopy characterization of biofluids and tissues related to hepatic diseases. Each section of this review highlights practical problems and solutions for conducting FTIR spectroscopy and microspectroscopy studies. [ABSTRACT FROM AUTHOR]

There is a continuous change in cell wall composition and organization during cotton fiber development. Cotton fiber strength correlates to the molecular weight (MW) and molecular weight distribution (MWD), and organization of cellulose chains in the secondary cell wall. These parameters change drastically during fiber development. This study reports on the MW, MWD, and organization of cellulose in cotton fibers harvested from two cotton cultivars of Gossypium hirsutum L., (Texas Marker-1 and TX55) at different levels of maturity. Fiber dissolution is necessary to estimate the molecular properties of cellulose. Cellulose in mature cotton fibers is larger in MW and highly crystalline and, therefore, poorly dissolves in common solvent systems. To facilitate the dissolution, fibers were first pretreated with 23% sodium hydroxide and then dissolved in a dimethylacetamide/lithium chloride solvent system. Gel permeation chromatography of dissolved fibers indicated that cellulose in both cultivars reaches its maximum MW around 30 days post anthesis. Fourier transform infrared microspectroscopy imaging in the transmission mode indicates changes in cellulose distribution in cotton fibers with fiber development. The distributions of infrared vibrations of cellulose at 897 (β-linkage of cellulose), 1161 (anti-symmetrical C-O-C stretching of cellulose), and 1429 cm−1 (CH2 scissoring of cellulose) provided information on cellulose deposition in intact cotton fibers. [ABSTRACT FROM AUTHOR]