Indolent T-cell lymphoproliferative disease of the gastrointestinal tract after treatment with adalimumab in resistant Crohn's colitis.

We report a case of intestinal indolent T-cell lymphoproliferative disease (TCLPD) occurring after the initiation of tumor necrosis factor-α (TNF-α) inhibitor therapy for resistant Crohn's disease. A prominent T-cell infiltrate positive for CD8, TIA-1, and T-cell receptor-ßF1 was associated with the foci of active inflammation. T-cell receptor gene clonality studies (BIOMED-2) demonstrated monoclonality. After the TNF-α inhibitor treatment was withdrawn, the T-cell infiltrates regressed, but 2 years later, the same monoclonal T-cell infiltrate reappeared at the only site of active inflammation. To the best of our knowledge, this report is the first to show a link between active inflammation and the TCLPD. In addition, it suggests a possible influence of the TNF-α inhibitor treatment on the evolution of the TCLPD. A high degree of suspicion is required in the presence of any unusual lymphoid infiltrate in inflammatory bowel disease to avoid overlooking an indolent TCLPD or misdiagnose an aggressive lymphoma.

Acellular cardiac extracellular matrix as a scaffold for tissue engineering: in vitro cell support, remodeling, and biocompatibility.

We have developed an efficient decellularization process for the isolation of extracellular matrix (ECM) from native cardiac tissue. The isolated ECM exhibited desirable mechanical properties in terms of elasticity, strength and durability-properties required from scaffolds used for cardiac tissue repair. This study further investigates the potential use of this scaffold for cardiac tissue engineering in terms of interactions with seeded cells and biocompatibility. We used the commonly studied fibroblasts, cardiomyocytes, and mesenchymal stem cells, which were isolated and seeded onto the scaffold. Cell density and distribution were followed by 3,3'-dioctadecyloxacarbocyanine perchlorate staining, and their proliferation and viability were assessed by AlamarBlue assay and fluorecein-diacetate/propidium iodide staining. Fibroblast-seeded scaffolds shrank to 1-2 mm(3) spheroids, and their glycosaminoglycans significantly increased by 23%. The expression of ECM remodeling-related mRNAs of collagens I and III, matrix metalloproteinase 2, and type 1 tissue inhibitor of metalloproteinases was quantified by real-time polymerase chain reaction, and was found significantly elevated in fibroblast-seeded scaffold, compared with the control cells on plates. Fibroblast-seeded scaffolds lost some flexibility, yet gained strength compared with the acellular scaffolds, as shown by mechanical testing. Scaffold seeded with cardiomyocyte began to beat in concert few days after seeding, and the myocytes expressed typical functional cardiac markers such as alpha-actinin, troponin I, and connexin43. The cells revealed aligned elongated morphology, as presented by immunofluorescent staining and scanning electron microscopy. Mesenchymal stem cell-seeded scaffolds maintained viability over 24 days in culture. These findings further strengthen the potential use of acellular cardiac ECM as a biomaterial for heart regeneration.

Direct micro-haplotyping by multiple double PCR amplifications of specific alleles (MD-PASA).

Analysis of haplotypes is an important tool in population genetics, familial heredity and gene mapping. Determination of haplotypes of multiple single nucleotide polymorphisms (SNPs) or other simple mutations is time consuming and expensive when analyzing large populations, and often requires the help of computational and statistical procedures. Based on double PCR amplification of specific alleles, described previously, we have developed a simple, rapid and low-cost method for direct haplotyping of multiple SNPs and simple mutations found within relatively short specific regions or genes (micro-haplotypes). Using this method, it is possible to directly determine the physical linkage of multiple heterozygous alleles, by conducting a series of double allele-specific PCR amplification sets with simple analysis by gel electrophoresis. Application of the method requires prior information as to the sequence of the segment to be haplotyped, including the polymorphic sites. We applied the method to haplotyping of nine sites in the chicken HSP108 gene. One of the haplotypes in the population apparently arose by recombination between two existing haplotypes, and we were able to locate the point of recombination within a segment of 19 bp. We anticipate rapidly growing needs for SNP haplotyping in human (medical and pharmacogenetics), animal and plant genetics; in this context, the multiple double PCR amplifications of specific alleles (MD-PASA) method offers a useful haplotyping tool.