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3499 citation(s) found for "Xu, Timothy".

Genetic Variation in Tumor Necrosis Factor and the Nuclear Factor-κB Canonical Pathway and Risk of Non-Hodgkin's Lymphoma
Cerhan, James R. , Liu‐Mares, Wen, Fredericksen, Zachary S., Novak, Anne J. , Cunningham, Julie M. , Liebow, Mark , Wang, Alice H., Call, Timothy G. , Ansell, Stephen M. , Kay, Neil E. , Doǧan, Ahmet , Habermann, Thomas M. , Slager, Susan L. , Cerhan, James R

Cancer Epidemiology, Biomarkers & Prevention | November 6, 2008 | Volume: 17 | Issue: 11 | Pages: 3161-3169

10.1158/1055-9965.epi-08-0536 | PMID 18990758 Get It

Abstract Non-Hodgkin's lymphoma (NHL) is a cancer closely associated with immune function, and the tumor necrosis factor (TNF) G-308A promoter polymorphism, which influences immune function and regulation, was recently reported by the InterLymph Consortium to be associated with NHL risk. TNF signaling activates the nuclear factor-κB (NF-κB) canonical pathway, leading to transcriptional activation of multiple genes that influence inflammation and immune response. We hypothesized that, in addition to TNF signaling, common genetic variation in genes from the NF-κB canonical pathway may affect risk of NHL. We genotyped 54 single nucleotide polymorphisms (SNP) within TNF, lymphotoxin A LTA, and nine NF-κB genes from the canonical pathway (TNFRSF1A, TRADD, TRAF2, TRAF5, RIPK1, CHUK, IKBKB, NFKB1, and REL) in a clinic-based study of 441 incident cases and 475 frequency-matched controls. Tagging SNPs were selected from HapMap supplemented by putative functional SNPs for LTA/TNF. We used principal components and haplo.stats to model gene-level associations and logistic regression to model SNP-level associations. Compared with the wild-type (GG), the AA genotype for the TNF promoter polymorphism G-308A (rs1800629) was associated with increased risk of NHL [odds ratio (OR), 2.14; 95% confidence interval (95% CI), 0.94-4.85], whereas the GA genotype was not (OR, 1.00; 95% CI, 0.74-1.34). This association was similar for follicular lymphoma and diffuse large B-cell lymphoma. A previously reported LTA/TNF haplotype was also associated with NHL risk. In gene-level analysis of the NF-κB pathway, only NFKB1 showed a statistically significant association with NHL (P = 0.049), and one NFKB1 tagSNP (rs4648022) was associated with NHL risk overall (ordinal OR, 0.59; 95% CI, 0.41-0.84; Ptrend = 0.0037) and for each of the common subtypes. In conclusion, we provide additional evidence for the role of genetic variation in TNF and LTA SNPs and haplotypes with risk of NHL and also provide some of the first preliminary evidence for an association of genetic variation in NFKB1, a downstream target of TNF signaling, with risk of NHL. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3161–9)
A Phase I Study of Intravenous Oncolytic Reovirus Type 3 Dearing in Patients with Advanced Cancer
Vidal, Laura , Pandha, Hardev , Twigger, Katie, Vile, Richard G. , Melcher, Alan , Harrington, Kevin J. , Bono, Johann S. de , Yap, Timothy Anthony , White, Christine L. , Coffey, Matt C. , Melcher, Alan A , Harrington, Kevin , de Bono, Johann

Clinical Cancer Research | November 3, 2008 | Volume: 14 | Issue: 21 | Pages: 7127-7137

10.1158/1078-0432.ccr-08-0524 | PMID 18981012 Get It

Abstract Purpose: To determine the safety and feasibility of daily i.v. administration of wild-type oncolytic reovirus (type 3 Dearing) to patients with advanced cancer, assess viral excretion kinetics and antiviral immune responses, identify tumor localization and replication, and describe antitumor activity. Experimental Design: Patients received escalating doses of reovirus up to 3 × 1010 TCID50 for 5 consecutive days every 4 weeks. Viral excretion was assessed by reverse transcription-PCR and antibody response by cytotoxicity neutralization assay. Pretreatment and post-treatment tumor biopsies were obtained to measure viral uptake and replication. Results: Thirty-three patients received 76 courses of reovirus from 1 × 108 for 1 day up to 3 × 1010 TCID50 for 5 days, repeated every four weeks. Dose-limiting toxicity was not seen. Common grade 1 to 2 toxicities included fever, fatigue, and headache, which were dose and cycle independent. Viral excretion at day 15 was not detected by reverse transcription-PCR at 25 cycles and only in 5 patients at 35 cycles. Neutralizing antibodies were detected in all patients and peaked at 4 weeks. Viral localization and replication in tumor biopsies were confirmed in 3 patients. Antitumor activity was seen by radiologic and tumor marker (carcinoembryonic antigen, CA19.9, and prostate-specific antigen) evaluation. Conclusions: Oncolytic reovirus can be safely and repeatedly administered by i.v. injection at doses up to 3 × 1010 TCID50 for 5 days every 4 weeks without evidence of severe toxicities. Productive reoviral infection of metastatic tumor deposits was confirmed. Reovirus is a safe agent that warrants further evaluation in phase II studies.
KCNJ11 knockout morula re-engineered by stem cell diploid aggregation
Nelson, Timothy J. , Martinez‐Fernandez, Almudena , Terzic, André , Nelson, Timothy J

Philosophical Transactions of the Royal Society B: Biological Sciences | October 31, 2008 | Volume: 364 | Issue: 1514 | Pages: 269-276

10.1098/rstb.2008.0179 | PMID 18977736 Get It

KCNJ11 -encoded Kir6.2 assembles with ATP-binding cassette sulphonylurea receptors to generate ATP-sensitive K + (K ATP ) channel complexes. Expressed in tissues with dynamic metabolic flux, these evolutionarily conserved yet structurally and functionally unique heteromultimers serve as high-fidelity rheostats that adjust membrane potential-dependent cell functions to match energetic demand. Genetic defects in channel subunits disrupt the cellular homeostatic response to environmental stress, compromising organ tolerance in the adult. As maladaptation characterizes malignant K ATP channelopathies, establishment of platforms to examine progression of K ATP channel-dependent adaptive behaviour is warranted. Chimeras provide a powerful tool to assay the contribution of genetic variance to stress intolerance during prenatal or post-natal development. Here, KCNJ11 K ATP channel gene knockout↔wild-type chimeras were engineered through diploid aggregation. Integration of wild-type embryonic stem cells into zona pellucida-denuded morula derived from knockout embryos achieved varying degrees of incorporation of stress-tolerant tissue within the K ATP channel-deficient background. Despite the stress-vulnerable phenotype of the knockout, ex vivo derived mosaic blastocysts tolerated intrauterine transfer and implantation, followed by full-term embryonic development in pseudopregnant surrogates to produce live chimeric offspring. The development of adult chimerism from the knockout↔wild-type mosaic embryo offers thereby a new paradigm to probe the ecogenetic control of the K ATP channel-dependent stress response.
Pilot Study of Transesophageal Endoscopic Surgery: NOTES Esophagomyotomy, Vagotomy, Lymphadenectomy
Woodward, Timothy A., McCluskey, David, Wallace, Michael B. , Raimondo, Massimo , Mannone, John, Smith, C. Daniel , Wallace, Michael B

Journal of Laparoendoscopic & Advanced Surgical Techniques | September 26, 2008 | Volume: 18 | Issue: 5 | Pages: 743-745

10.1089/lap.2008.0226 | PMID 18803520 Get It

Reply to “Quality of life after tonsillectomy in children with recurrent tonsillitis”
Goldstein, Nira A. , Stewart, Michael G. , Witsell, David L., Hannley, Maureen, Weaver, Edward M. , Yueh, Bevan , Smith, Timothy L. , Orvidas, Laura J.

Otolaryngology–Head and Neck Surgery | September 25, 2008 | Volume: 139 | Issue: 4 | Pages: 608-609

10.1016/j.otohns.2008.07.012 Get It

Headache Disorders in Developing Countries: Research Over The Past Decade
Mateen, Farrah J. , Dua, Tarun , Steiner, Timothy J. , Saxena, Shekhar , Mateen, Farrah

Cephalalgia | August 22, 2008 | Volume: 28 | Issue: 11 | Pages: 1107-1114

10.1111/j.1468-2982.2008.01681.x | PMID 18727634 Get It

The majority of people with primary headache disorders live in the developing world. The contribution of low and middle income (LAMI) countries to headache research has not been previously characterized. A search was performed for clinical research publications between the years 1997 and 2006, using the search terms ‘headache’ OR ‘headache disorders’ AND ‘primary’ OR ‘migraine’ AND ‘each of the LAMI countries’ in 67 databases. Articles in English or with abstracts in English translation were included. These publications were scrutinized for study characteristics. Two hundred and twenty-seven publications from 32 LAMI countries were found. Half (50.2±) of these were from three middle-income countries (Brazil, Turkey and Iran), whereas 24 (10.6±) came from low-income countries. Most of the research focused on migraine. Only 29.5± of the articles involved treatment of headache. The understanding of headache disorders in LAMI countries is derived from a limited number of publications from relatively few countries. Identifying gaps in headache research in the developing world is strategic for targeting research policy.
Methods and processes for the reanalysis of the NINDS tissue plasminogen activator for acute ischemic stroke treatment trial
Hertzberg, Vicki , Ingall, Timothy J., O’Fallon, W. Michael, Asplund, Kjell , Louis, Thomas A. , Christianson, Teresa J., Goldfrank, Lewis R.

Clinical Trials | August 12, 2008 | Volume: 5 | Issue: 4 | Pages: 308-315

10.1177/1740774508094404 | PMID 18697845 Get It

Background Treatment group imbalances in baseline stroke severity in the NINDS intravenous t-PA for acute stroke treatment trial led to controversy regarding the efficacy of tissue plasminogen activator (t-PA) in the treatment of acute ischemic stroke. Purpose Describe the steps used to independently re-evaluate this trial. Methods NIH appointed an independent multidisciplinary committee that gained access to the original data. We undertook analyses of t-PA efficacy accounting for this imbalance, as well as analyses to identify subgroups that experienced additional harm or benefit from t-PA. Analyses of time from stroke onset to treatment (OTT), blood pressure, and intracerebral hemorrhage are given as illustrations. Results Despite subgroup imbalances in baseline stroke severity, when t-PA was administered to acute ischemic stroke patients according to study protocol, there was a statistically significant and clinically important benefit of t-PA treatment resulting in a higher likelihood of having a favorable clinical outcome at 3 months. Moreover, we were unable to identify subgroups of patients between which t-PA treatment effect differed, albeit these analyses had low power. These data failed to support the NINDS investigators' conclusion that effect of t-PA therapy diminished with increasing values of OTT within the protocol-specified 3 h time limit. In addition, the blood pressure measurements were highly variable and inconsistently determined so as to be too unreliable for inclusion in analysis. Conclusion With new NIH requirements for data-sharing, the frequency of re-analysis of clinical trial data may increase substantially. This re-evaluation provides a blueprint for future re-evaluations of other trials. These best practices include re-analysis of the study data, after suitable replication, by an independent multidisciplinary committee, including a skilled statistical programmer analyst. Primary investigators should address significant errors determined in such re-analyses. Clinical Trials 2008; 5: 308—315. http://ctj.sagepub.com
Tumor Cell and Tumor Vasculature Expression of B7-H3 Predict Survival in Clear Cell Renal Cell Carcinoma
Crispen, Paul L. , Sheinin, Yuri, Roth, Timothy J., Lohse, Christine M. , Kuntz, Susan M., Frigola, Xavier, Thompson, R. Houston, Boorjian, Stephen A. , Leibovich, Bradley C. , Blute, Michael L., Kwon, Eugene D., Dong, Haidong

Clinical Cancer Research | August 11, 2008 | Volume: 14 | Issue: 16 | Pages: 5150-5157

10.1158/1078-0432.ccr-08-0536 | PMID 18694993 Get It

Abstract Purpose: Although the prognostic value of B7-H1 and B7-H4 expression by tumor cells in clear cell renal cell carcinoma (ccRCC) has been established, the role of B7-H3 is unknown. As such, we evaluated the association of B7-H3 expression with clinicopathologic outcomes in patients treated for ccRCC. Experimental Design: Nephrectomy specimens from 743 consecutive patients treated for ccRCC at our institution from 1990 to 1999 were evaluated for B7-H3 expression by immunohistochemical staining. Associations of B7-H3 expression with clinical and pathologic features were evaluated using χ2 and Fisher's exact tests. Associations of B7-H3 expression with death from RCC were evaluated using Cox proportional hazards regression models. Results: B7-H3 expression by tumor cells or tumor vasculature was noted in 17% and 95% of specimens, respectively. The presence of either tumor cell or diffuse tumor vasculature expression of B7-H3 was present in 46% of specimens and was associated with multiple adverse clinical and pathologic features. After multivariable adjustment, the presence of either tumor cell or diffuse tumor vasculature B7-H3 expression was significantly associated with an increased risk of death from RCC (risk ratio, 1.38; 95% confidence interval, 1.03-1.84; P = 0.029). Conclusions: Both tumor cell and tumor vasculature B7-H3 expression convey important information to predict ccRCC outcomes. Collectively, our past and present studies pertaining to B7-H ligand expression indicate that ccRCC may use redundant mechanisms to compromise host antitumoral immunity. Future studies will focus on the effect of combined B7-H ligand expression in RCC.
Patient with both Wilkie syndrome and nutcracker syndrome
Barsoum, Michel K., Shepherd, Roger F.J., Welch, Timothy J.

Vascular Medicine | August 7, 2008 | Volume: 13 | Issue: 3 | Pages: 247-250

10.1177/1358863x08092272 | PMID 18687762 Get It

Abstract Wilkie syndrome or superior mesenteric artery syndrome is a rare cause of duodenal obstruction in pediatric and adult age groups. Its manifestations are due to compression of the third portion of the duodenum between the aorta and the superior mesenteric artery. We present one case of a 29-year-old female with a recent history of epigastric pain and severe weight loss due to duodenal obstruction from superior mesenteric syndrome. She was treated conservatively with jejunostomy tube feeding to regain loss of weight. Our case is unique in that the patient has also nutcracker syndrome.
Role of N-linked oligosaccharides in the biosynthetic processing of the cystic fibrosis membrane conductance regulator
Chang, Xiu-Bao, Mengos, April, Hou, Yue-xian, Cui, Liying , Jensen, Timothy J., Aleksandrov, Andrei A. , Riordan, John R., Gentzsch, Martina

Journal of Cell Science | August 6, 2008 | Volume: 121 | Issue: 17 | Pages: 2814-2823

10.1242/jcs.028951 | PMID 18682497 Get It

The epithelial chloride channel CFTR is a glycoprotein that is modified by two N-linked oligosaccharides. The most common mutant CFTR protein in patients with cystic fibrosis, ΔF508, is misfolded and retained by ER quality control. As oligosaccharide moieties of glycoproteins are known to mediate interactions with ER lectin chaperones, we investigated the role of N-linked glycosylation in the processing of wild-type and ΔF508 CFTR. We found that N-glycosylation and ER lectin interactions are not major determinants of trafficking of wild-type and ΔF508 from the ER to the plasma membrane. Unglycosylated CFTR, generated by removal of glycosylation sites or treatment of cells with the N-glycosylation inhibitor tunicamycin, did not bind calnexin, but did traffic to the cell surface and exhibited chloride channel activity. Most importantly, unglycosylated ΔF508 CFTR still could not escape quality control in the early secretory pathway and remained associated with the ER. However, the absence of N-linked oligosaccharides did reduce the stability of wild-type CFTR, causing significantly more-rapid turnover in post-ER compartments. Surprisingly, the individual N-linked carbohydrates do not play equivalent roles and modulate the fate of the wild-type protein in different ways in its early biosynthetic pathway.