Biomedical subjects

Jonathan Pollack

Publications and source records attributed to Jonathan Pollack.

5 recordsLinked to original sources

PubMed2026

High-Dose Intravenous Vitamin C and Mortality and Organ Dysfunction in Severe Burn Injury: The VICTORY Randomized Clinical Trial.

IMPORTANCE: Severe burn injury triggers systemic inflammation that can lead to multiple organ dysfunctions and death. High-dose intravenous vitamin C has been proposed to mitigate these effects, but strong evidence in patients with burn injury is lacking. OBJECTIVE: To evaluate the efficacy of high-dose intravenous vitamin C in patients with severe burn injury. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind, placebo-controlled phase 3 trial conducted across 24 burn centers in North, Central, and South America; Europe; and Asia. Adults (≥18 years) with deep second- and/or third-degree burns covering 20% or more of total body surface area and requiring skin grafting were enrolled between August 18, 2020, and September 12, 2025. Final follow-up was completed in March 2026. The trial was stopped early after the first prespecified interim analysis for futility/harm. INTERVENTIONS: Patients were randomly assigned (1:1) to receive intravenous vitamin C (50 mg/kg every 6 hours for 96 hours) or matched placebo. MAIN OUTCOMES AND MEASURES: The primary outcome was a composite of 28-day mortality and persistent organ dysfunction (defined as dependence on mechanical ventilation, kidney replacement therapy, or vasopressor/inotrope support at day 28). The main secondary outcome was time to discharge alive from hospital within 90 days. RESULTS: Among 238 patients enrolled (mean age, 48.9 [SD, 19.1] years; 79% male; mean total body surface area, 37.0% [SD, 14.6%]), 120 were assigned to vitamin C and 118 to placebo. The primary composite outcome occurred in 49 patients (40.8%) in the vitamin C group and 35 patients (29.7%) in the placebo group (adjusted risk ratio [RR], 1.28 [95% CI, 0.99-1.65]; P = .06), crossing the prespecified futility/harm threshold and prompting early trial termination. Time to discharge alive from hospital within 90 days was not improved (adjusted subdistribution hazard ratio, 0.85 [95% CI, 0.62-1.16]; P = .31). Twenty-eight-day mortality was higher in the vitamin C group (15.0% vs 7.6%; adjusted RR, 1.96 [95% CI, 1.32-2.90]; P = .001), as was hospital mortality (23.3% vs 16.1%; adjusted RR, 1.44 [95% CI, 1.03-2.00]; P = .03). CONCLUSIONS AND RELEVANCE: Among patients with severe burn injury, high-dose intravenous vitamin C did not reduce 28-day mortality and persistent organ dysfunction and is possibly harmful. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04138394.

Humans↗

PubMed2006

DNA microarray and proteomic strategies for understanding alcohol action.

This article summarizes the proceedings of a symposium presented at the 2005 annual meeting of the Research Society on Alcoholism in Santa Barbara, California. The organizer was James M. Sikela, and he and Michael F. Miles were chairs. The presentations were (1) Genomewide Surveys of Gene Copy Number Variation in Human and Mouse: Implications for the Genetics of Alcohol Action, by James M. Sikela; (2) Regional Differences in the Regulation of Brain Gene Expression: Relevance to the Detection of Genes Associated with Alcohol-Related Traits, by Robert Hitzemann; (3) Identification of Ethanol Quantitative Trait Loci Candidate Genes by Expression Profiling in Inbred Long Sleep/Inbred Short Sleep Congenic Mice, by Robnet T. Kerns; and (4) Quantitative Proteomic Analysis of AC7-Modified Mice, by Kathleen J. Grant.

Alcoholism↗

PubMed2005

Amplification of EMSY, a novel oncogene on 11q13, in high grade ovarian surface epithelial carcinomas.

OBJECTIVES: Amplification of the 11q13 locus is commonly observed in a number of human cancers including both breast and ovarian cancer. Cyclin D1 and EMS1 have been implicated as candidate oncogenes involved in the emergence of amplification at this locus. Detailed analysis of the 11q13 amplicon in breast cancer led to the discovery of four regions of amplification suggesting the involvement of other genes. Here, we investigate the role of EMSY, a recently described BRCA2 interacting protein, as a key element of the 11q13 amplicon in ovarian cancer. EMSY maps to 11q13.5 and is amplified in 13% of breast and 17% of ovarian carcinomas. METHODS: EMSY amplification was assessed by fluorescent in-situ hybridization (FISH) in 674 ovarian cancers in a tissue microarray and correlated with histopathological subtype and tumor grade. A detailed map of the 11q13 amplicon in 51 cases of ovarian cancer was obtained using cDNA-array-based comparative genomic hybridization (aCGH). To further characterize the role of EMSY within this amplicon, we evaluated both the amplification profiles and RNA expression levels of EMSY and two other genes from the 11q13 amplicon in an additional series of 22 ovarian carcinomas. RESULTS: EMSY amplification was seen in 52/285 (18%) high grade papillary serous carcinomas, 4/27 (15%) high grade endometrioid carcinomas, 3/38 (8%) clear cell carcinomas, and 3/10 (30%) undifferentiated carcinomas. aCGH mapping of 11q13 in ovarian cancer showed that EMSY localized to the region with the highest frequency of copy number gain. Cyclin D1 and EMS1 showed a lower frequency of copy number gain. A highly significant correlation between EMSY gene amplification and RNA expression was also observed (P = 0.0001). This was a stronger correlation than for other genes at 11q13 including Cyclin D1 and PAK1. CONCLUSIONS: These findings support the role of EMSY as a key oncogene within the 11q13 amplicon in ovarian cancer.

Chromosome Mapping↗

PubMed2005

A method for calling gains and losses in array CGH data.

Array CGH is a powerful technique for genomic studies of cancer. It enables one to carry out genome-wide screening for regions of genetic alterations, such as chromosome gains and losses, or localized amplifications and deletions. In this paper, we propose a new algorithm 'Cluster along chromosomes' (CLAC) for the analysis of array CGH data. CLAC builds hierarchical clustering-style trees along each chromosome arm (or chromosome), and then selects the 'interesting' clusters by controlling the False Discovery Rate (FDR) at a certain level. In addition, it provides a consensus summary across a set of arrays, as well as an estimate of the corresponding FDR. We illustrate the method using an application of CLAC on a lung cancer microarray CGH data set as well as a BAC array CGH data set of aneuploid cell strains.

Algorithms↗

PubMed2004

Lineage-specific gene duplication and loss in human and great ape evolution.

Given that gene duplication is a major driving force of evolutionary change and the key mechanism underlying the emergence of new genes and biological processes, this study sought to use a novel genome-wide approach to identify genes that have undergone lineage-specific duplications or contractions among several hominoid lineages. Interspecies cDNA array-based comparative genomic hybridization was used to individually compare copy number variation for 39,711 cDNAs, representing 29,619 human genes, across five hominoid species, including human. We identified 1,005 genes, either as isolated genes or in clusters positionally biased toward rearrangement-prone genomic regions, that produced relative hybridization signals unique to one or more of the hominoid lineages. Measured as a function of the evolutionary age of each lineage, genes showing copy number expansions were most pronounced in human (134) and include a number of genes thought to be involved in the structure and function of the brain. This work represents, to our knowledge, the first genome-wide gene-based survey of gene duplication across hominoid species. The genes identified here likely represent a significant majority of the major gene copy number changes that have occurred over the past 15 million years of human and great ape evolution and are likely to underlie some of the key phenotypic characteristics that distinguish these species.

Animals↗