Themed collection Optical Diagnosis (2014)

Malgorzata Baranska and Hugh J. Byrne, co-chairs of SPEC 2014, welcome you to this themed issue on the topic of Optical Diagnosis which focuses on recent developments of in-vivo, ex-vivo and in-vitro clinical applications of vibrational spectroscopy.

Vibrational spectroscopy for biomedical applications has shown great promise although its translation into clinical practice has, as yet, been relatively slow. This Editorial assesses the challenges facing the field and the potential way forward.

A new optical system has recently been developed that enables infrared images to be obtained with a pixel resolution of 1 micron on a bench-top instrument using a thermal source.

Mucin density is rapidly visualized in unstained, paraffin-embedded mouse colon tissue by means of mid-infrared spectroscopy using quantum cascade lasers.

Confocal Raman microspectroscopy was used in this study to identify hepatic stellate cells (HSCs) from healthy mice and mice with untreated and treated liver steatosis.

(DSC) and (TGA) investigations, acetate electrophoresis (CAE), infrared spectrometry (FTIR), scanning electron microscopy (SEM) and microbiological procedures were all carried out after heating the samples to a temperature sufficient for simulating a burn incident.

The effect of sample preparation and substrate choice in the apoptosis of dorsal root ganglion neurons using FTIR widefield microscopy.

“Large” nanoparticles potentially are a good starting point in order to derive informative NIR/IR SERS analysis of biological samples.

FTIR spectroscopy may provide a specific, rapid, and inexpensive method for the successful classification of Colletotrichum coccodes isolates into vegetative compatibility groups.

In this paper we have presented the first example of multiplexing pH and redox responsive SERS nanosensors for intracellular live single cell measurement on a cell by cell basis.

We discussed the potential of lipid droplets in nonmalignant and malignant human breast epithelial cell lines as a prognostic marker in breast cancer.

Chiroptical spectroscopy is able to discriminate colon cancer patients from healthy controls.

We present the results of Raman studies in the temperature range of 293–77 K on vibrational properties of linoleic and oleic acids and Raman microspectroscopy of human breast tissues at room temperature.

This paper introduces algorithms for identifying overlapping observations between Raman and fluorescence microscopic images of one and the same sample.

We provide evidence that phenylalanine/tyrosine (Phe/Tyr) ratio analysis by Raman spectroscopy discriminate endothelial dysfunction in ApoE/LDLR^−/− mice as compared to control animals.

FTIR microspectroscopy coupled with UCP1 immunohistological staining enables the detection of obesity-related molecular alterations and transdifferentiations in visceral and subcutaneous adipose tissues in spontaneously obese mice lines.

Differential distribution of paraffin in a normal colon tissue section after various de-Waxing procedures in comparison to a paraffinized tissue.

In this study, ketogenic diet-induced biochemical changes occurring in normal and epileptic hippocampal formations were compared.

Modern medical treatment can be improved by nanotechnology methods for preparing nanocomposites with novel physical, chemical and biological properties.

FTIR microscopy of adjacent sections of tissue measured by transmission and transflection shows comparable images after UHCA.

Tissue phantoms were created with embedded biomineral-simulating inclusions of varying size and depth, and formed of different mixtures of CaCO₃ and hydroxyapatite, for comparison of deep Raman spectroscopy techniques.

FTIR imaging from samples using translation rather than transmission mode leads to increased variance in the spectra. Whether this matters for spectral pathology is still a matter of debate.

Results of a study comparing infrared imaging data sets collected on different instruments or instrument platforms are reported, along with detailed methods developed to permit such comparisons.

We report results on a statistical analysis of an infrared spectral dataset comprising a total of 388 lung biopsies from 374 patients.

FTIR as a new approach to screen a rare disease.

Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) and Raman spectroscopy were used to compare chloroquine (CQ)-treated and untreated cultured Plasmodium falciparum-infected human red blood cells (iRBCs).

Raman spectroscopy highlights biochemical changes that are spectrally or spatially related to the presence of the malaria pigment, hemozoin, inside macrophage cells, during the initial stages of exposure.

The hierarchical double application of crisp cluster validity indices for automated spectral histology of a normal human colon.

Clostridium difficile infection (CDI) has become one of the major public health threats in the last two decades.

We developed an in vitro model of early neural cell development.

The paper demonstrates that Raman imaging has reached a clinically relevant level in regard to breast cancer diagnosis applications.

This work focuses on obtaining unique representative FTIR spectrum characteristic for one type of cells architecture. Presented idea is based on using of HCA for data evaluation to search for uniform patterns within samples from the perspective of FTIR spectra.

Novel high spatial resolution (1 × 1 μm pixel) FTIR imaging with commercial benchtop instrument yields data comparable to that from synchrotron sources.

In this work FTIR studies on blood plasma in the rat models of hypertension are reported.

Anthracycline antibiotics display genotoxic activity towards cancer cells but their clinical utility is limited by their cardiac and vascular toxicity.

Chiroptical spectroscopy is able to detect conformational changes of plasmatic biomolecules during type 1 diabetes mellitus.

In this study, we established how the depth of penetration into cartilage varies throughout the NIR frequency range (4000–10 000 cm⁻¹).

Serum Raman spectroscopy was explored for prediction of oral cancer recurrence in before surgery and after surgery blood samples. Findings suggest RS of post-surgery samples may help in prediction of recurrence.

In this study Raman spectral data from peripheral blood mononuclear cells (PBMCs) is used for the competitive evaluation of three data-mining models in discriminating a highly pure population of T-cell lymphocytes from other myeloid cells within the PBMCs fraction.

We report results from a study utilizing infrared spectral cytopathology (SCP) to detect abnormalities in exfoliated esophageal cells.

Infrared spectra of cell smears change in shape with cell density.

Breast cancer cell lines in 2D (top) and 3D (bottom) culture: H&H, unstained bright field, and IR images.

FTIR imaging can identify the main cell types of melanoma tumors and can help identify primary melanomas with the highest risk of metastases.

In the drive towards biomedical applications of Raman spectroscopy, it is critically important to validate the data analysis tools.

Raman microspectroscopy was applied to characterize the local and global biochemical changes associated with calcification in human stenotic aortic valves.

Peripheral blood cytotoxic T cells (CD8+), helper T cells (CD4+) and regulatory T cells (T reg) have unique spectral signatures in the mid-infrared.

Fourier transform infrared (FTIR) microspectroscopy is assessed in terms of two techniques (i.e., transmission and transflection) as a method for rapid measurements of blood plasma.

FTIR imaging enables to effectively discriminate lymphocyte subpopulations without antibody labelling.

Protein-related changes associated with the development of human brain gliomas are of increasing interest in modern neuro-oncology.

The composition of mice lung tissue was investigated using Raman confocal microscopy at 532 nm excitation wavelength supported with different experimental staining techniques as well as DFT calculations.

Automated detection of lung cancer adenocarcinoma subtypes by FTIR imaging is presented in this study for the first time.

The intracellular pH plays an important role in various cellular processes.

Alterations in the α-helix and β-sheet content and the lipid-to-protein ratio are the most striking features of hypertension development in the vascular endothelium.

FTIR spectroscopy is a widely used technique that provides insights into disease processes at the molecular level.

Preliminary FTIR measurements of adrenal gland biocomposition as the first step to find a spectral biomarker of malignancy phenotype.

The applications of optical spectroscopic methods in cancer detection open new possibilities in oncological diagnostics.

Permutation testing in the evaluation of the statistical significance for infrared based classification of biological samples.

Analysis of urine by Raman spectroscopy (RS) as an alternative screening and diagnostic tool for breast cancer..