European Society of Toxicologic Pathology (Pathology 2.0 Molecular Pathology Special Interest Group): Review of In Situ Hybridization Techniques for Drug Research and Development

In situ hybridization (ISH) is used for the localization of specific nucleic acid sequences in cells or tissues by complementary binding of a nucleotide probe to a specific target nucleic acid sequence. In the last years, the specificity and sensitivity of ISH assays were improved by innovative techniques like synthetic nucleic acids and tandem oligonucleotide probes combined with signal amplification methods like branched DNA, hybridization chain reaction and tyramide signal amplification. These improvements increased the application spectrum for ISH on formalin-fixed paraffin-embedded tissues. ISH is a powerful tool to investigate DNA, mRNA transcripts, regulatory noncoding RNA, and therapeutic oligonucleotides. ISH can be used to obtain spatial information of a cell type, subcellular localization, or expression levels of targets. Since immunohistochemistry and ISH share similar workflows, their combination can address simultaneous transcriptomics and proteomics questions. The goal of this review paper is to revisit the current state of the scientific approaches in ISH and its application in drug research and development.

Microbiological Etiology of Chronic Skin Lesions in Type 2 Diabetic Subjects

INTRODUCTION

Skin lesions represent lesions that result in loss of tissues and their joints and often this cutaneous process is a primary or secondary consequence of structural changes in the same skin surface. Type 2 diabetic subjects developing chronic skin lesions in the lower limbs in the western world are steadily increasing. We conducted a study on the etiologic incidence of chronic skin lesions in type II diabetic subjects in the lower limbs compared to subjects with chronic skin lesions (controls).

MATERIALS AND METHODS

Thirty subjects (group "A") with Chronic Skin Lesions (CSL controls) (19 F-11M, mean age 67.5±7.2) in the lower limbs were admitted to our study according to a randomization scheme and compared a thirty (group "B") type II diabetic patients (18F-12M, mean age 73.5±4.9) with chronic skin lesions (CSL). These two groups "A" and "B" have been studied and compared on the basis of infectious etiology responsible for the infectious skin process.

RESULT

In the subjects of the "A" group we found a positive bacteriological colony test of 9 examinations corresponding to the total 30.0%. In the group called "B" we obtained a colony test positive of 12 subjects over 30 corresponding to 40.0% of the examinations. For the number of bacterial species identified in the "A" group we obtained 7 monomicrobial and 2 poly microbial bacteriological tests, while in the "B" group we observed 3 mono microbial and 9 poly microbial tests. All bacteriological isolates showed "in vitro" sensitivity to satisfactory aminoglycosides with MICs range of 0.78- 1.56mg/L.

CONCLUSIONS

Data from this study show a different etiology among diabetic subjects than nondiabetic subjects. In fact, in the "B" group, more poly microbial bacteriological findings are found in positive culture studies with subjects in group "A". This phenomenon confirms an alteration of the skin microbiome of diabetic subjects with modification of the "opportunistic role" of some species of the skin bacterial flora.