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Goodman, C.

Publications and source records attributed to Goodman, C..

4 recordsLinked to original sources

Origin and Correlates of Viral Rebound in SIV-Infected Rhesus Macaques Following ART Discontinuation

The vast majority of persons living with HIV-1 who discontinue antiretroviral therapy (ART) demonstrate viral rebound, but the tissue-level events that lead to rebound viremia are poorly understood. Here we report the origin, dynamics, and correlates of viral rebound in 16 rhesus macaques (RMs) infected with molecularly barcoded SIVmac239M, treated with ART for 70 weeks, and necropsied on day 12 after ART discontinuation. Barcode analysis of plasma following ART discontinuation identified 1 to 38 rebounding barcode-defined viral lineages per animal, with 1 to 4 rebounding lineages contributing to first measurable rebound viremia. Analysis of barcode viral RNA (vRNA) expression in necropsy tissues revealed presumptive anatomic origin sites for 56 of 175 total rebounding viral lineages, with significant enrichment in the gastrointestinal (GI) tract and GI-associated lymph nodes. Daily transcriptomic and proteomic profiling in peripheral blood following ART discontinuation showed upregulation of pathways related to T cell signaling, cytokine responses, and cellular metabolism prior to detectable rebound viremia. These data suggest that viral rebound following ART discontinuation is initiated by local tissue replication of a limited number of clonal lineages, followed by systemic expansion of the initial rebounding lineages and serial initiation of replication of multiple additional clonal lineages. These findings provide mechanistic insights into the processes that result in viral rebound following ART discontinuation and will contribute to next generation HIV-1 cure strategies.

microbiology↗

Haptoglobin and glutamine synthetase may biomark cachexia induced by anti-acute myeloid leukemia chemotherapy

BackgroundAnti-cancer chemotherapy is an underappreciated contributor to cancer cachexia, an often irreversible body-wasting condition that causes 20-30% of cancer-related deaths. An obstacle to predicting, monitoring and understanding the mechanisms underlying chemotherapy cachexia is that each cancer (and sub-type) is assigned different chemotherapeutic compounds, typically in multi-agent regimens. Here, we investigate the chemotherapy induction regimen (CIR) used in the haematological cancer, acute myeloid leukemia (AML). We hypothesized that the AML CIR would induce cachexia, including loss of lean tissue mass and skeletal muscle atrophy. MethodsUsing an unbiased proteomics approach we interrogated the underlying molecular mechanisms. 3-month-old male Balb/c mice were treated with the AML CIR via intraperitoneal injections of daunorubicin (1.7 mg/kg) on days 1-3, and cytarabine (33.2 mg/kg) administered on days 1-7 or vehicle. Mice were assessed 24 hours after the last treatment, on day 8, or allowed to recover for 2 weeks and assessed on day 22. A third cohort was given access to running wheels in cages. We assessed body composition, whole body metabolism and assessed the muscle proteome using quantitative tandem mass tag labelling LC-MS/MS analysis. ResultsThe AML CIR-induced acute cachexia involved a [~]10% loss of body mass, [~]10% loss of lean mass and [~]20% reduction in skeletal muscle fibre size. Whole body metabolism and ambulatory activity declined. This cachexic phenotype did not recover over the 2-week post-CIR period (lean mass loss post-CIR: 1 week [~]7% vs 2 weeks [~]9%). In voluntarily active CIR-treated mice, body wasting was exacerbated due to unchecked loss of fat mass (CIR sedentary: [~]31% vs CIR active: [~]51%). Muscle proteome studies revealed upregulation of haptoglobin (Hp) and glutamine synthetase (Glul), which were positively correlated with body and lean mass loss. Hp was sensitive to the conditional induction, recovery and exacerbation of AML CIR-mediated cachexia, suggestive of biomarker potential. ConclusionsThe AML CIR induces an acute reduction of body, lean and fat mass underpinned by skeletal muscle atrophy, hypermetabolism and catabolism. Our data uncovered a conditionally sensitive muscle biomarker in Hp, which may be useful as a prognostic tool across other scenarios of chemotherapy-induced myopathy and cachexia or as a target for therapeutic discovery in follow-up studies.

physiology↗

Colorful Lizards and the Conflict of Collection

Invasive species threaten biodiversity and their management is economically burdensome. Research on the indirect effects of introduced species are often focused on indirect ecological effects, with little focus on the more difficult to capture but critically important societal impacts. Often understated are the social costs of invasive species such as conflicts between invasive species managers and public stakeholders. Chameleons are popular in the pet trade and have been introduced throughout Florida, and their presence often attracts private collectors. After locating a population of panther chameleons (Furcifer pardalis) within a suburban neighborhood in central Florida, we administered anonymous questionnaires to residents to explore how this introduction and the ensuing species collection has affected them. Respondents had knowledge of chameleon presence but most expressed low concern about chameleon presence. Respondents who had observed chameleons in the area expressed more concern for their safety given the activities of private collectors. Our study highlights the importance of recognizing the social impacts of species introductions in urban environments, particularly the attention these species can draw and the mixed perception of these species among stakeholders.

ecology↗

A high-throughput metabolic microarray assay reveals antibacterial effects of black and red raspberries and blackberries against Helicobacter pylori infection

Helicobacter pylori is an important bacterial pathogen that causes chronic infection of the human stomach, leading to gastritis, peptic ulcer disease and gastric cancer. Treatment with appropriate antibiotics can eliminate H. pylori infection and reduce the risk for severe disease outcomes. However, since H. pylori is becoming increasingly resistant to standard antibiotic regimens, novel treatment strategies are needed. Previous studies have demonstrated that black and red berries may have antibacterial properties. Therefore, we analyzed organic extracts and powders from black and red raspberries and blackberries and determined their antibacterial effects on multiple H. pylori strains. We used high-performance liquid chromatography to measure berry anthocyanins, which are considered the major active ingredients. To monitor antibiotic effects of the berry preparations on H. pylori, we developed a high-throughput metabolic growth assay based on the OmniLog system. All berry preparations tested had significant bactericidal effects in vitro, with MIC90 values ranging from 0.49 to 4.17%. We next used human gastric epithelial organoids to evaluate biocompatibility of the berry preparations and showed that black raspberry extract, which had the strongest antimicrobial activity, was non-toxic at the concentration required for complete bacterial growth inhibition. To determine whether dietary black raspberry application could eliminate H. pylori infection in vivo, mice were infected with H. pylori and then were placed on a diet containing 10% black raspberry powder. However, this treatment did not significantly impact bacterial infection rates or gastric pathology. In summary, our data indicate that black and red raspberry and blackberry products have potential applications in the treatment and prevention of H. pylori infection, because of their antibacterial effects and good biocompatibility. However, delivery and formulation of berry compounds needs to be optimized to achieve significant antibacterial effects in vivo.

microbiology↗