Publications by authors named "Alicia Volkheimer"

A promising strategy to cure HIV infected individuals is to use latency reversing agents (LRAs) to reactivate latent viruses, followed by host clearance of infected reservoir cells. However, reactivation of latent proviruses within infected cells is heterogeneous and often incomplete. This fact limits strategies to cure HIV which may require complete elimination of viable virus from all cellular reservoirs.

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This study sought to identify neuroimaging and immunological factors associated with substance use and that contribute to neurocognitive impairment (NCI) in people with HIV (PWH). We performed cross-sectional immunological phenotyping, neuroimaging, and neurocognitive testing on virally suppressed PWH in four substance groups: cocaine only users (COC), marijuana only users (MJ), dual users (Dual), and Non-users. Participants completed substance use assessments, multimodal MRI brain scan, neuropsychological testing, and blood and CSF sampling.

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Alteration in RNA splicing is implicated in carcinogenesis and progression. Mutations in spliceosome genes and alternative splicing of other genes have been noted in chronic lymphocytic leukaemia (CLL), a common B cell malignancy with heterogeneous outcomes. We previously demonstrated that differences in the amount of SET oncoprotein (a physiological inhibitor of the serine/threonine phosphatase, PP2A) is associated with clinical aggressiveness in patients with CLL.

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Chronic lymphocytic leukaemia (CLL) is characterized by expression of CD5 on clonal B cells, and is partly driven by activated B-cell receptor (BCR) signalling. While CD5 is known to be a negative regulator of BCR signalling, it is unknown if variability in CD5 expression exists among patients and whether CLL cell CD5 expression affects CLL clinical outcomes. We assessed the extent to which CD5 expression is correlated with clinical outcomes, and whether this information adds to currently used prognostic markers.

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Objective: To determine the functional effect of missense mutations in 2 children with intellectual disability and developmental delay but no seizures.

Methods: Genomic DNA was analyzed by next-generation sequencing. variants were introduced into the Na1.

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Rituximab therapy for B cell chronic lymphocytic leukemia (B-CLL) has met with mixed success. Among several factors to which resistance can be attributed is failure to activate complement dependent cytotoxicity (CDC) due to protective complement regulatory proteins, including the soluble regulator complement factor H (CFH). We hypothesized that rituximab killing of non-responsive B-CLL cells could be augmented by a novel human monoclonal antibody against CFH.

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We earlier established that nitric oxide (NO) is protective against severe malaria and that arginine and NO levels are reduced in malaria patients. We now show that an M2-like blood monocyte phenotype is significantly associated with hypoargininemia, NO insufficiency, and disease severity in Tanzanian children with falciparum malaria. Compared to control children (n = 106), children with moderately severe (n = 77) and severe falciparum malaria (n = 129) had significantly higher mononuclear cell arginase 1 mRNA, protein, and enzyme activity; lower NOS2 mRNA; lower plasma arginine; and higher plasma IL-10, IL-13, and IL-4.

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Decreased bioavailability of nitric oxide (NO) is a major contributor to the pathophysiology of severe falciparum malaria. Tetrahydrobiopterin (BH4) is an enzyme cofactor required for NO synthesis from L-arginine. We hypothesized that systemic levels of BH₄ would be decreased in children with cerebral malaria, contributing to low NO bioavailability.

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Introduction: Impaired T cell function in sepsis is associated with poor outcome, but the mechanisms are unclear. In cancer, arginase-expressing myeloid derived suppressor cells (MDSCs) deplete arginine, impair T cell receptor CD3 zeta-chain expression and T cell function and are linked to poor clinical outcome, but their role during acute human infectious disease and in particular sepsis remains unknown. Hypoarginemia is prevalent in sepsis.

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Background: Nitric oxide (NO) bioavailability is impaired in children and adults with severe falciparum malaria (SM). Asymmetric-dimethylarginine (ADMA) limits NO production by inhibiting NO synthase and is increased in adult SM. The role of ADMA in the pathogenesis of childhood SM is unknown.

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Abstract Because of the importance of the phosphoinositide 3-kinase (PI3K)/AKT pathway in chronic lymphocytic leukemia (CLL), we evaluated in vitro cytotoxicity induced by perifosine, an AKT inhibitor, in CLL lymphocytes and found that the mean 50% effective dose (ED50) was 313 nM. We then performed a phase II trial of perifosine in patients with relapsed/refractory CLL to assess response, outcomes, toxicity and ex vivo correlative measures. After 3 months of treatment, six of eight patients showed stable disease, one achieved a partial response and one had progressive disease.

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B-cell chronic lymphocytic leukemia (CLL), an incurable leukemia, is characterized by defective apoptosis. We found that the SET oncoprotein, a potent inhibitor of the protein phosphatase 2A (PP2A) tumor suppressor, is overexpressed in primary CLL cells and B-cell non-Hodgkin lymphoma (NHL) cell line cells. In CLL, increased levels of SET correlated significantly with disease severity (shorter time to treatment and overall survival).

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Purpose: Chronic lymphocytic leukemia (CLL) is a B-cell malignancy characterized by a variable clinical course. Several parameters have prognostic capabilities but are associated with altered response to therapy in only a small subset of patients.

Experimental Design: We used gene expression profiling methods to generate predictors of therapy response and prognosis.

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Nitric oxide synthase (NOS) inhibitors induce chronic lymphocytic leukemia (CLL) cell apoptosis and have potential as CLL therapeutics. We determined the half-maximal concentration (ED(50)) of 22 NOS inhibitors that induced CLL cell death in vitro. There was a direct correlation of the NOS1 (but not NOS2) dissociation constant (K(d)) and the hydrophobicity partitioning coefficient of each NOS inhibitor and its ED(50).

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Several parameters may predict disease severity and overall survival in chronic lymphocytic leukemia (CLL). The purpose of our study of 190 CLL patients was to compare immunoglobulin heavy chain variable region (IgV(H)) mutation status, cytogenetic abnormalities, and leukemia cell CD38 and Zap-70 to older, traditional parameters. We also wanted to construct a simple, inexpensive prognosis score that would significantly predict TTT and survival in patients at the time of diagnosis and help practicing clinicians.

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Somatic mutations of immunoglobulin genes characterize mature memory B cells, and intraclonal B-cell diversification is typically associated with expansion of B-cell clones with greater affinity for antigen (antigen drive). Evidence for a role of antigen in progression of intraclonal chronic lymphocytic leukemia (CLL) cell diversification in patients with mutated immunoglobulin genes has not been previously presented. We performed a single-cell analysis of immunoglobulin heavy and light chains in 6 patients with somatically mutated CLL-cell immunoglobulin genes and identified 2 patients with multiple related (oligoclonal) subgroups of CLL cells.

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