Karen Hubbard

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Seventy fecal samples from spotted hyenas (Crocuta crocuta) in the Masai Mara National Reserve, Kenya were examined for parasite eggs and oocysts using sugar flotation. A total of nine parasite genera were identified, and all samples were positive for at least one parasite species. Most individuals were infected with Ancylostoma sp. and Spirometra sp., and(More)
Heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) is a RNA binding protein that plays important role in the biogenesis of mRNA, such as alternative splicing and mRNA stability. We have previously demonstrated that hnRNP A1 has diminished protein levels and shows cytoplasmic accumulation in senescent human diploid fibroblasts. Recent reports showed that(More)
OBJECTIVE To test the hypothesis that mitochondrial DNA (mtDNA) deletions are more prevalent in granulosa cells from women of advanced reproductive age than from younger women undergoing IVF. DESIGN Granulosa cells screened for presence or absence of the 4977-bp deletion in human mtDNA. SETTING University-based fertility clinic. PATIENT(S) Twenty-four(More)
Solar radiation can lead to changes affecting DNA metabolism resulting in loss of DNA integrity. Skin specimens obtained from melanoma patients treated at the Memorial Sloan-Kettering Cancer Center were used to study patterns of DNA fragmentation using the comet assay and levels of deletions in mitochondrial DNA (mtDNA) using real-time PCR. Skin specimens(More)
Heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) is an RNA-binding protein that modulates splice site usage, polyadenylation, and cleavage efficiency. This protein has also been implicated in mRNA stability and transport from the nucleus. We have previously demonstrated that hnRNP A1 had diminished protein levels and showed cytoplasmic accumulation in(More)
Cellular senescence is a terminal growth phase characteristic of normal human diploid fibroblasts. Altered gene expression during cellular senescence is numerous compared to that of younger proliferative cells in culture. We have previously reported that the levels and activities of hnRNP A1 and A2 RNA binding proteins are decreased in senescent human(More)
Chemotherapy is associated with long-term cognitive deficits in breast cancer survivors. Studies suggest that these impairments result in the loss of cognitive reserve and/or induce a premature aging of the brain. This study has been aimed to determine the potential underlying mechanisms that induce cognitive impairments by chemotherapeutic agents commonly(More)
Cellular senescence is an irreversible growth phase characteristic of normal cells. We have found that human senescent fibroblasts can be induced to undergo programmed cell death (apoptosis) by ceramide, TNF-alpha, or okadaic acid. The most profound effects were induced by TNF-alpha and okadaic acid treatment. In the present study, we also evaluated the(More)
We measured the cellular levels of two types of mitochondrial DNA (mtDNA) deletions--the 4977-bp common deletion and recently identified UVB-induced deletion of 5128 bp--in apparently normal skin obtained from wide excisions in melanoma patients. The number of deleted mtDNAs as well as the total mtDNA copy number was highly variable, but the number of(More)
Spatial properties of cell assays obtained by monitoring morphological characteristics of incubated cancer cells are studied as cell apoptosis indicators. Human colon carcinoma cells were cultured in 3d in-vitro microenvironment with FOLFOX treatment to experimentally evaluate cell viability for multiple days. With a 3D cell tracking algorithm guiding an(More)