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Steven Wang

Publications and source records attributed to Steven Wang.

13 recordsLinked to original sources
PubMed2026

Cell-free DNA genomic and fragmentomic features for early outcome prediction in large B cell lymphoma.

Curative-intent immunochemotherapy fails in ∼30% of patients with large B cell lymphoma (LBCL), yet no validated molecular tool enables early identification of high-risk individuals to guide treatment intensification. Using shallow whole-genome sequencing (sWGS) of plasma cell-free DNA from 190 LBCL patients, we develop and validate the ACT score (aberrations, composition of fragments, and terminal motif analyses), a composite classifier integrating genomic and fragmentomic features from a single post-cycle-1 sample. ACT-positive patients have worse 2-year outcomes versus ACT-negative patients: time-to-progression 29% vs. 83% (hazard ratio [HR]: 4.4, 95% confidence interval [CI]: 1.9-10.0; p = 1.5 × 10-4) and overall survival 47% vs. 93% (HR: 8.7, 95% CI: 3.0-25.4; p = 1.8 × 10-6). The ACT score is independently prognostic of the International Prognostic Index, and their combination identifies the highest risk patients. Unlike mutation-based approaches, this assay requires neither tumor tissue, germline control, nor a baseline plasma sample. Built on open-source tools and sWGS, the ACT score offers a feasible, scalable strategy for early risk stratification in aggressive LBCL.

Humans↗
PubMed2006

Wheat bran oil and its fractions inhibit human colon cancer cell growth and intestinal tumorigenesis in Apc(min/+) mice.

This study was designed to investigate the cancer preventive activities of wheat bran (WB) oil. We studied the colon cancer preventive effects of WB oil and its subfractions in the Apc(min/+) mouse model, a recognized mouse model for human colorectal cancer, and used human colon cancer cell lines (HCT-116 and HT-29) to identify possible active fractions in WB oil. Our results showed that the oil fraction of WB was more active than the water fraction against the growth of human colon cancer cell lines and that 2% WB oil significantly inhibited the overall tumorigenesis by 35.7% (p < 0.0001) in the Apc(min/+) mouse model. The WB oil was further fractioned into nonpolar lipids and phytochemicals and the phytochemical fraction was fractionated into phytosterols and phytosterol ferulates, 5-alk(en)ylresorcinols, and unidentified constituents by normal phase silica gel column chromatography. Results on cell culture showed that the phytochemical fraction had a higher inhibitory effect on HCT-116 human colon cancer cells than that of WB oil, whereas the nonpolar lipid fraction had less growth inhibitory effectiveness. However, neither fractions showed a stronger inhibition than WB oil in the Apc(min/+) mouse model. The current results demonstrate, for the first time, the intestinal cancer preventive activity of WB oil. The active ingredients, however, remain to be identified.

Animals↗
PubMed2006

"Fat fingers:" a clue in the dermoscopic diagnosis of seborrheic keratoses.

"Fat fingers" are thick digitate linear, curvilinear, branched, or oval/circular dermoscopic structures typically seen in seborrheic keratoses where they represent the gyri of their cerebriform surfaces. Their recognition is very useful in the diagnosis of these lesions, especially when the classic features (eg, milia, comedo-like openings) are absent. Histologically and by confocal microscopy the "fat finger" gyri are accentuated by pigmented keratin filling the sulci. "Fat fingers" must be differentiated from other linear structures such as "network-like structures"; branched streaks; network; globules; pigmented ovoid-nests; and streaks/pseudopods seen in different melanocytic and non-melanocytic lesions.

Adult↗
PubMed2005

A qualitative examination of primary care providers' and physician managers' uses and views of research evidence.

OBJECTIVE: To examine the reasons and search strategies related to physicians' search for evidence and to compare clinician and physician manager approaches. DESIGN: Qualitative analysis of verbatim transcripts of four focus groups in 2002. Study setting. Clinicians and managers in community practices in Southern California. PARTICIPANTS: Pediatricians, family practitioners, and general internists (i.e. child and adult primary care providers) in non-academic practice and physician managers whose primary responsibility involved making management decisions within a moderate to large sized health care delivery system (e.g. health plan, community hospital, large group practice). MAIN OUTCOME MEASURES: Themes related to clinician and manager reasons for using evidence and approach to selecting among evidence sources. RESULTS: Clinicians and managers differed substantially in their reasons for using evidence. Whereas clinicians consistently invoked clinical intuition as a guide to most routine clinical decisions, managers articulated both motivation and interest in using medical research to guide decision-making, most commonly prompted by cost. Both clinicians and managers rated trustworthiness as a paramount consideration in arbitrating between evidence sources, because neither group evinced comfort with the complexity of primary literature. Both groups expressed a preference for tested, convenient, and respected evidence sources such as expert colleagues and professional societies. CONCLUSIONS: Because clinicians invoke intuition in confronting the challenges of daily practice, evidence-based medicine interventions that target managers are likely to have larger effects on health outcomes than those that target primary care providers and individual patient treatment. Ensuring trustworthiness of evidence is of the utmost importance. Because both groups express discomfort with the format of primary evidence sources, strategies should probably not rely on individual appraisal.

Adult↗
PubMed2005

Prolonged treatment of genetically obese mice with conjugated linoleic acid improves glucose tolerance and lowers plasma insulin concentration: possible involvement of PPAR activation.

BACKGROUND: Studies in rodents and some studies in humans have shown that conjugated linoleic acid (CLA), especially its trans-10, cis-12 isomer, reduces body fat content. However, some but not all studies in mice and humans (though none in rats) have found that CLA promotes insulin resistance. The molecular mechanisms responsible for these effects are unclear, and there are conflicting reports on the effects of CLA on peroxisomal proliferator-activated receptor-gamma (PPARgamma) activation and expression. We have conducted three experiments with CLA in obese mice over three weeks, and one over eleven weeks. We have also investigated the effects of CLA isomers in PPARgamma and PPARalpha reporter gene assays. RESULTS: Inclusion of CLA or CLA enriched with its trans-10, cis-12 isomer in the diet of female genetically obese (lepob/lepob) mice for up to eleven weeks reduced body weight gain and white fat pad weight. After two weeks, in contrast to beneficial effects obtained with the PPARgamma agonist rosiglitazone, CLA or CLA enriched with its trans-10, cis-12 isomer raised fasting blood glucose and plasma insulin concentrations, and exacerbated glucose tolerance. After 10 weeks, however, CLA had beneficial effects on glucose and insulin concentrations. At this time, CLA had no effect on the plasma TNFalpha concentration, but it markedly reduced the plasma adiponectin concentration. CLA and CLA enriched with either isomer raised the plasma triglyceride concentration during the first three weeks, but not subsequently. CLA enriched with its trans-10, cis-12 isomer, but not with its cis-9, trans-11 isomer, stimulated PPARgamma-mediated reporter gene activity; both isomers stimulated PPARalpha-mediated reporter gene activity. CONCLUSIONS: CLA initially decreased but subsequently increased insulin sensitivity in lepob/lepob mice. Activation of both PPARgamma and PPARalpha may contribute to the improvement in insulin sensitivity. In the short term, however, another mechanism, activated primarily by trans-10, cis-12-CLA, which probably leads to reduced adipocyte number and consequently reduced plasma adiponectin concentration, may decrease insulin sensitivity.

Adiponectin↗
PubMed2004

Topiramate, carbamazepine, and valproate monotherapy: double-blind comparison in children with newly diagnosed epilepsy.

In a novel double-blind trial, topiramate was compared with the investigator's choice of carbamazepine or valproate as first-line therapy in patients as young as 6 years of age with newly diagnosed epilepsy. Among 613 patients enrolled in the trial, 119 (19%) were children or adolescents (6-16 years of age). No differences between fixed doses of topiramate (100 and 200 mg/day) and carbamazepine (600 mg/day) or valproate (1250 mg/day) were observed in efficacy measures: time to exit, time to first seizure, and the proportion of patients who were seizure free during the last 6 months of treatment. Topiramate 100 mg/day (2.0 mg/kg/day in this study population) was associated with the fewest discontinuations owing to side effects. Based on efficacy and tolerability, the recommended target dose for topiramate as first-line therapy in children and adolescents is 100 mg/day.

Adolescent↗
PubMed2003

A signalling role for 4-hydroxy-2-nonenal in regulation of mitochondrial uncoupling.

Oxidative stress and mitochondrial dysfunction are associated with disease and aging. Oxidative stress results from overproduction of reactive oxygen species (ROS), often leading to peroxidation of membrane phospholipids and production of reactive aldehydes, particularly 4-hydroxy-2-nonenal. Mild uncoupling of oxidative phosphorylation protects by decreasing mitochondrial ROS production. We find that hydroxynonenal and structurally related compounds (such as trans-retinoic acid, trans-retinal and other 2-alkenals) specifically induce uncoupling of mitochondria through the uncoupling proteins UCP1, UCP2 and UCP3 and the adenine nucleotide translocase (ANT). Hydroxynonenal-induced uncoupling was inhibited by potent inhibitors of ANT (carboxyatractylate and bongkrekate) and UCP (GDP). The GDP-sensitive proton conductance induced by hydroxynonenal correlated with tissue expression of UCPs, appeared in yeast mitochondria expressing UCP1 and was absent in skeletal muscle mitochondria from UCP3 knockout mice. The carboxyatractylate-sensitive hydroxynonenal stimulation correlated with ANT content in mitochondria from Drosophila melanogaster expressing different amounts of ANT. Our findings indicate that hydroxynonenal is not merely toxic, but may be a biological signal to induce uncoupling through UCPs and ANT and thus decrease mitochondrial ROS production.

Animals↗
PubMed2003

Effect of rosiglitazone on the differential expression of obesity and insulin resistance associated proteins in lep/lep mice.

Peroxisome proliferator-activated receptors (PPARs) participate in the molecular mechanism of pathologies with altered lipid homeostasis such as type 2 diabetes or obesity. The insulin sensitizer drug, rosiglitazone, has been shown to bind and activate PPAR-gamma1 in adipocytes and PPAR-gamma2 in hepatocytes. The identification of new molecular targets associated with fatty acid oxidation and PPAR-gamma nuclear receptor regulation in insulin resistance tissues is a key research goal. In the present study, we have used a proteomic approach to identify such targets. Lean and obese C57 Bl/6J lep/lep mice were given BRL49653, rosiglitazone, 10 mg/kg diet, by dietary admixture for 7 days. Rosiglitazone normalized the impaired glucose tolerance and dyslipidemia in lep/lep mice but had no significant effect in the lean mice. Samples of liver, white and brown adipose tissue, and muscle proteins were obtained and 100 microg of proteins was arrayed by two-dimensional gel electrophoresis. Thirty-four polypeptides were differentially expressed (p < 0.05) between lep/lep and lean mice and eleven were significantly (p < 0.05) modulated by rosiglitazone treatment of the obese mice. None of the proteins was modulated by rosiglitazone treatment of the lean mice. The identity of these differentially expressed proteins was made using tandem mass spectrometric analysis and revealed components of fatty acid and carbohydrate metabolism as well as proteins with unknown function.

Animals↗
PubMed2002

Effect of rosiglitazone on the differential expression of diabetes-associated proteins in pancreatic islets of C57Bl/6 lep/lep mice.

The insulin sensitizer drug, rosiglitazone, has been shown to have a protective effect on pancreatic islet cell structure and function in animal models of type 2 diabetes. The identification of new molecular targets associated both with islet cell dysfunction and protection is a crucial research goal. In the present study, a proteomics approach has been used to identify such targets. Obese C57Bl/6J lep/lep mice and lean littermates were given the insulin sensitizer drug BRL49653, rosiglitazone. It normalized the impaired glucose tolerance in lep/lep mice but had no significant effect on glucose tolerance in the lean mice. Pancreatic islet polypeptides were arrayed by a two-dimensional gel electrophoresis system that separated more than 2500 individual spots. Three overexpressed and six underexpressed proteins were significant (p < 0.05) between lep/lep and lean mice, and four were modulated significantly (p < 0.05) by the rosiglitazone treatment of the obese mice. The identity of these differentially expressed proteins was made using mass spectrometric analysis and provided evidence that differential expression of actin-binding proteins may be an important aspect of defective islet function. Rosiglitazone increased carboxypeptidase B expression in both lep/lep and normal mice suggesting that this might be an independent effect of rosiglitazone that contributes to improved insulin processing.

Animals↗
PubMed2002

Biodistribution of a 153 Gd-folate dendrimer, generation = 4, in mice with folate-receptor positive and negative ovarian tumor xenografts.

RATIONALE AND OBJECTIVES: An important characteristic of targeted contrast agents is how they are tolerated in a biologic environment and their localization in the surrounding tissues in addition to target tissue. We evaluate the biodistribution of a gadolinium Gd 153-folate-dendrimer in high affinity folate-receptor (hFR) positive and negative ovarian tumor xenografts. METHODS: The 153Gd-folate-dendrimer chelate was prepared by exchanging 153Gd with nonradioactive gadolinium for 1 week, followed by extensive filtration. Athymic mice with hFR-positive (n = 3) and negative tumors (n = 3) were injected intravenously and counted using a whole-body counting system with a 80 to 150 keV counting window. RESULTS: The hFR-positive tumors accumulate 3.6% +/- 2.8% injected dose/g, whereas only background counts were found in hFR-negative tumors. The folate-dendrimer's tumor-to-blood ratio of 12.6, in hFR-positive tumors, was approximately 5.7 to 17.0 fold better than those obtained with monoclonal antibodies targeted to the folate receptor. CONCLUSIONS: Biodistribution studies confirm previous MRI findings and show that the accumulation of the folate-dendrimer requires the expression of the hFR.

Animals↗
PubMed2002

Enhanced diabetogenic effect of streptozotocin in mice overexpressing UCP-3 in skeletal muscle.

Diabetic patients exhibit varying degrees of increased muscle UCP-3 expression in skeletal muscle and, in rodents, the pancreatoxin streptozotocin (STZ) upregulates UCP-3 mRNA in skeletal and cardiac muscles. We have investigated the development of STZ-induced diabetes in transgenic mice overexpressing UCP-3 in skeletal muscle in order to provide further insight on the functional role of muscle UCP-3. UCP-3 transgenic mice treated with STZ (UCP3-STZ) showed a significant increase in blood glucose concentration 3 days after the last dose of STZ with a progressive induction of diabetes, attaining blood glucose concentrations of 24.7 +/- 1.5 mmol/L on day 17. Wild-type mice treated with STZ (WT-STZ) only started to show an increase in blood glucose concentration 6 days after the last dose of STZ and peaked on day 17 at a lower concentration than in the UCP-STZ mice. The pancreatic insulin content of UCP-3 control mice (UCP3-CON) was decreased relative to wild-type control mice (WT-CON), and STZ reduced the total pancreatic insulin content by 72% in WT-STZ mice and by 88% in UCP3-STZ mice. In an insulin tolerance test, blood glucose concentrations declined more in the UCP-3 transgenic mice than in the wild-type mice. Mice overexpressing UCP-3 in skeletal muscle have a lower pancreatic insulin content, but tend to be more insulin-sensitive. These twin actions result in an increased susceptibility to STZ-induced diabetes in UCP-3 transgenic mice.

Animals↗
PubMedDate not supplied

Topiramate for migraine prevention in adolescents: a pooled analysis of efficacy and safety.

OBJECTIVE: To characterize the efficacy and safety of topiramate for migraine prevention in adolescents from 3 randomized, 26-week, double-blind, placebo-controlled trials. BACKGROUND: Limited information is available regarding the efficacy and safety of prophylactic medications for treatment of adolescent migraine, a significant health problem. In studies that included adults and children, topiramate 100 and 200 mg/day were effective and generally well-tolerated in the prevention of migraine headache. METHODS: We performed a post hoc subset analysis of the efficacy and safety data from the 51 patients, ages 12-17 years, enrolled in 3 pivotal trials of topiramate for migraine prophylaxis. RESULTS: Daily treatment with topiramate 50, 100, and 200 mg for 26 weeks reduced monthly migraine frequency from baseline 46% (P= .07), 63% (P= .02), and 65% (P= .04), respectively, compared with placebo (16%). Similarly, topiramate reduced both the monthly mean number of migraine days (1, 4, and 5 days for topiramate 50, 100, and 200 mg/day, respectively, vs 1 day for placebo) and percentage of days during which acute migraine medications were administered (59%, 54%, and 67% for topiramate 50, 100, and 200 mg/day, respectively, vs 42% for placebo), although the treatment differences did not reach nominal statistical significance. Topiramate 200 mg/day did not appear to offer greater efficacy than 100 mg/day. Treatment was generally well-tolerated, although adverse events were most frequent in the 200 mg/day dose group. CONCLUSIONS: This post hoc subset analysis suggests that topiramate 100 and 200 mg/day, and possibly 50 mg/day, administered prophylactically for 26 weeks may reduce migraine in adolescents.

Adolescent↗