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How to develop highly informative serology assays to evaluate the quality of immune protection against coronavirus disease‐19 (COVID‐19) has been a global pursuit over the past years. Here, a microfluidic high‐plex immuno‐serolomic assay is developed to simultaneously measure50 plasma or serum samples for50 soluble markers including 35proteins, 11 anti‐spike/receptor binding domian (RBD) IgG antibodies spanningmajor variants, and controls. This assay demonstrates the quintuplicate test in a single run with high throughput, low sample volume, high reproducibilityand accuracy. It is applied to the measurement of 1012 blood samples including in‐depth analysis of sera from 127 patients and 21 healthy donors over multiple time points, either with acute COVID infection or vaccination. The protein analysis reveals distinct immune mediator modules that exhibit a reduced degree of diversity in protein‐protein cooperation in patients with hematologic malignancies or receiving B cell depletion therapy. Serological analysis identifies that COVID‐infected patients with hematologic malignancies display impaired anti‐RBD antibody response despite high level of anti‐spike IgG, which can be associated with limited clonotype diversity and functional deficiency in B cells. These findings underscore the importance to individualize immunization strategies for these high‐risk patients and provide an informative tool to monitor their responses at the systems level. [ABSTRACT FROM AUTHOR]

Choroideremia is an X‐linked recessive retinal degeneration predominantly affecting hemizygous males. It is caused by mutations in the CHM gene that encodes the Rab escort protein‐1. Characteristic features include early nyctalopia followed by progressive constriction of peripheral visual fields and sparing of the central vision until late in life with a distinct fundoscopic appearance. We present the case of a 17‐year‐old male with a c.282delT in exon 4 of CHM that has not previously been reported. Phenotypically this patient presented with an atypical choroideremia phenotype of early central macular degeneration in addition to the classic peripheral fundus characteristic findings. [ABSTRACT FROM AUTHOR]

A locus on human chromosome 11q23 tagged by marker rs3802842 was associated with colorectal cancer (CRC) in a genome-wide association study; this finding has been replicated in case-control studies worldwide. In order to identify biologic factors at this locus that are related to the etiopathology of CRC, we used microarray-based target selection methods, coupled to next-generation sequencing, to study 103 kb at the 11q23 locus. We genotyped 369 putative variants from 1,030 patients with CRC (cases) and 1,061 individuals without CRC (controls) from the Ontario Familial Colorectal Cancer Registry. Two previously uncharacterized genes, COLCA1 and COLCA2, were found to be co-regulated genes that are transcribed from opposite strands. Expression levels of COLCA1 and COLCA2 transcripts correlate with rs3802842 genotypes. In colon tissues, COLCA1 co-localizes with crystalloid granules of eosinophils and granular organelles of mast cells, neutrophils, macrophages, dendritic cells and differentiated myeloid-derived cell lines. COLCA2 is present in the cytoplasm of normal epithelial, immune and other cell lineages, as well as tumor cells. Tissue microarray analysis demonstrates the association of rs3802842 with lymphocyte density in the lamina propria ( p = 0.014) and levels of COLCA1 in the lamina propria ( p = 0.00016) and COLCA2 (tumor cells, p = 0.0041 and lamina propria, p = 6 × 10-5). In conclusion, genetic, expression and immunohistochemical data implicate COLCA1 and COLCA2 in the pathogenesis of colon cancer. Histologic analyses indicate the involvement of immune pathways. [ABSTRACT FROM AUTHOR]

The requirement of Akt for cell proliferation and oncogenesis is mammalian target of rapamycin complex 1 (mTORC1) dependent. SV40 large T expression in Akt-deficient cells restores cell proliferation rate, but is insufficient for exiting contact inhibition and oncogene-induced anchorage-independent growth, because of a failure to promote Skp2 mRNA translation. Skp2 mRNA and protein are induced upon exiting contact inhibition, which enables entry into mitosis. While Skp2 mRNA is induced in Akt-deficient cells, it is not translated, preventing entry into mitosis. Restoring Skp2 expression in Akt-deficient cells is sufficient to restore exit from contact inhibition and oncogenesis. Skp2 mRNA translation is dependent on mTORC1 and the eukaryotic translation initiation factor 4E (eIF4E). Thus, the requirement of Akt for exiting contact inhibition is mediated by the induction of Skp2 mRNA translation in eIF4E-dependent mechanism. These results provide a new insight into the role of the Akt/mTORC1/eIF4E axis in tumourigenesis. Akt-dependent Skp2 mRNA translation is also required for mitotic clonal expansion (MCE)-the earliest event in adipogenesis. Skp2 re-expression in Akt-deficient preadipocytes, which are impaired in adipogenesis, is sufficient to restore adipogenesis. These results uncover the mechanism by which Akt mediates adipogenesis. [ABSTRACT FROM AUTHOR]

Azacitidine and decitabine are cytidine analogues that inhibit DNA methylation, and are used to treat myeloid haematological malignancies. Hydroxycarbamide (HC) (also known as hydroxyurea), a ribonucleotide reductase (RR) inhibitor, blocks the conversion of ribonucleotides to deoxyribonucleotides, and is also used to treat leukaemia and sickle-cell disease. Azacitidine is a ribonucleoside and decitabine is a deoxyribonucleoside; therefore, we hypothesized that inhibition of RR by HC would be antagonistic to azacitidine and synergistic to decitabine. HL-60 and T24 cancer cell lines were treated with azacitidine or decitabine in combination with HC and DNA methylation of LRE1, MAGEA1 and CDKN2A was quantitatively measured by bisulphite-polymerase chain reaction pyrosequencing. Surprisingly, we found that HC blocked the ability of both azacitidine and decitabine to inhibit DNA methylation and this antagonistic effect was attributable to the arrest of the cell cycle induced by HC. However, this antagonism could be avoided with sequential treatment of HC followed by azacitidine or decitabine. This data suggest that concurrent combination of HC blocks the ability of azacitidine and decitabine to inhibit DNA methylation and therefore these drugs should be used sequentially. [ABSTRACT FROM AUTHOR]

Deals with a study which characterized the presence of nuclear matrix metalloproteinase-2 (MMP-2) activity and hypothesize that its role may include degradation of the nuclear matrix protein poly (ADP-ribose) polymerase (PARP). Determination of the subcellular localization of MMP-2; Comparison of the amino acid sequence of bovine PARP with various MMP-2 cleavage recognition sequences.

The article discusses a dual-setting mentoring program for female medical students at Queen's University School of Medicine in Kingston, Ontario. It describes how the mentoring program was designed to address the increasing numbers of female medical trainees and the limited number of female physician mentors using the dual-setting, or large- and small-group model.

Azacitidine and decitabine are cytidine analogues that inhibit DNA methylation, and are used to treat myeloid haematological malignancies. Hydroxycarbamide (HC) (also known as hydroxyurea), a ribonucleotide reductase (RR) inhibitor, blocks the conversion of ribonucleotides to deoxyribonucleotides, and is also used to treat leukaemia and sickle-cell disease. Azacitidine is a ribonucleoside and decitabine is a deoxyribonucleoside; therefore, we hypothesized that inhibition of RR by HC would be antagonistic to azacitidine and synergistic to decitabine. HL-60 and T24 cancer cell lines were treated with azacitidine or decitabine in combination with HC and DNA methylation of LRE1, MAGEA1 and CDKN2A was quantitatively measured by bisulphite-polymerase chain reaction pyrosequencing. Surprisingly, we found that HC blocked the ability of both azacitidine and decitabine to inhibit DNA methylation and this antagonistic effect was attributable to the arrest of the cell cycle induced by HC. However, this antagonism could be avoided with sequential treatment of HC followed by azacitidine or decitabine. This data suggest that concurrent combination of HC blocks the ability of azacitidine and decitabine to inhibit DNA methylation and therefore these drugs should be used sequentially.