Significant advances have been made in the past decade in the field of mass spectrometry imaging (MS imaging). It is a relatively unestablished technique aimed at direct, high-sensitive and spatially exclusive detection of biological molecules from the surface of tissue sections, so that semi-quantitative distribution map of the analyte can be reconstituted from the mass spectra obtained. There...

Since emerging in the late 19(th) century, formaldehyde fixation has become a standard method for preservation of tissues from clinical samples. The advantage of formaldehyde fixation is that fixed tissues can be stored at room temperature for decades without concern for degradation. This has led to the generation of huge tissue banks containing thousands of clinically significant samples. Here...

Background: Anogenital wart is a common sexually transmitted disease affecting both genders. The aim of this study was to evaluate human papilloma virus types of anogenital warts with Polymerase Chain Reaction (PCR). Method: 65 formalin fixed paraffin embedded (FFPE) tissue blocks of the anogenital warts obtained from the pathology lab of Loghman Hakim hospital were included in this study. Resu...

BACKGROUND Current reference methods for evaluating gene amplification and expression of ERBB2 (also known as HER-2)--cell-based fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC)--are subjective and influenced by methods of tissue preparation and fixation. We developed and evaluated a novel, quantitative liquid-based FISH (L-FISH) assay that uses flow cytometry to detect ...

Formalin-fixed paraffin-embedded (FFPE) samples represent a valuable resource for clinical researches. However, FFPE samples are usually considered an unreliable source for gene expression analysis due to the partial RNA degradation. In this study, through comparing gene expression profiles between FFPE samples and paired fresh-frozen (FF) samples for three cancer types, we firstly showed that ...

Background: Formalin-fixed paraffin-embedded (FFPE) specimen archives are a valuable source of sample material for molecular biological analysis. However, the DNA isolated from FFPE samples is usually low in concentration and fragmented. Thus, it necessary to optimize extraction protocol obtain best results. Proteinase K incubation undoubtedly crucial procedures, but this step often not well ex...

KRAS mutation has been unambiguously identified as a marker of resistance to cetuximab-based treatment in metastatic colorectal cancer (mCRC) patients. However, most studies of KRAS mutation analysis have been performed using homogenously archived CRC specimens, and studies that compare freshly frozen specimens and formalin-fixed paraffin-embedded (FFPE) specimens of CRC are lacking. The aim of...

Formalin-fixed paraffin-embedded (FFPE) tissue samples represent a potentially invaluable resource for transcriptomic-based research into the molecular basis of disease. However, use of FFPE samples in gene expression studies has been limited by technical challenges resulting from degradation of nucleic acids. Here we evaluated gene expression profiles derived from fresh-frozen (FRO) and FFPE m...

Few data are available regarding the reliability of fluorescence in-situ hybridization (FISH), especially for chromosomal deletions, in high-throughput settings using tissue microarrays (TMAs). We performed a comprehensive FISH study for the detection of chromosomal translocations and deletions in formalin-fixed and paraffin-embedded (FFPE) tumor specimens arranged in TMA format. We analyzed 46...

BACKGROUND Rickettsia rickettsii, Rickettsia parkeri, and Rickettsia akari are the most common causes of spotted fever group rickettsioses indigenous to the United States. Infected patients characteristically present with a maculopapular rash, often accompanied by an inoculation eschar. Skin biopsy specimens are often obtained from these lesions for diagnostic evaluation. However, a species-spe...