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202. Genomic loci susceptible to systematic sequencing bias in clinical whole genomes

Author

Freeman, Timothy M., Wang, Dennis, and Harris, Jason

Abstract

Accurate massively parallel sequencing (MPS) of genetic variants is key to many areas of science and medicine, such as cataloging population genetic variation and diagnosing genetic diseases. Certain genomic positions can be prone to higher rates of systematic sequencing and alignment bias that limit accuracy, resulting in false positive variant calls. Current standard practices to differentiate between loci that can and cannot be sequenced with high confidence utilize consensus between different sequencing methods as a proxy for sequencing confidence. These practices have significant limitations, and alternative methods are required to overcome them. We have developed a novel statistical method based on summarizing sequenced reads from whole-genome clinical samples and cataloging them in “Incremental Databases” that maintain individual confidentiality. Allele statistics were cataloged for each genomic position that consistently showed systematic biases with the corresponding MPS sequencing pipeline. We found systematic biases present at ∼1%–3% of the human autosomal genome across five patient cohorts. We identified which genomic regions were more or less prone to systematic biases, including large homopolymer flanks (odds ratio = 23.29–33.69) and the NIST high confidence genomic regions (odds ratio = 0.154–0.191). We confirmed our predictions on a gold-standard reference genome and showed that these systematic biases can lead to suspect variant calls within clinical panels. Our results recommend increased caution to address systematic biases in whole-genome sequencing and alignment. This study provides the implementation of a simple statistical approach to enhance quality control of clinically sequenced samples by flagging variants at suspect loci for further analysis or exclusion.

Published
2020
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204. Training and Assessment of Clinician’s Utilization of the Los Angeles Classification for Reflux Esophagitis

Author

Dadgar, Kayla, Wang, Dennis, Yuan, Yuhong, Sinclair, Paul, Sharma, Prateek, and Armstrong, David

Abstract

Background: Endoscopic recognition of reflux esophagitis is critical for the evaluation and treatment of patients with gastroesophageal reflux disease; however, there are limited data on the need for education to minimize interobserver disagreement in clinical practice.Methods: We created an educational program for the LA classification on the International Working Group for the Classification of Oesophagitis (IWGCO)website that included endoscopic video recordings of the distal esophagus. Participants completed an entry survey before the training module and were able to proceed to subsequent training videos once they provided the correct LA classification. Participants then completed a test module—an 80% score was required to pass. Descriptive analyses and regression analyses were performed to analyze data.Results: In the entry survey, 83/90 (92%) participants reported using the LA classification for the majority or all patients with reflux symptoms. However, only 31/90 (34%) participants reported feeling very or completely confident in the use of the LA classification. Only 3/71 (4.2%) participants correctly classified all 9 training videos on their first attempt. The testing module was completed by 60 participants, 16 (26.7%) of whom passed after one attempt, with 32 (53.3%), 8 (13.3%), and 1 (1.7%) passing after 2, 3, and 4 attempts, respectively. There was no significant correlation between the number of attempts to successfully pass the testing module and participant characteristics.Conclusion: Even after a training module, >75% of participants required more than one attempt to correctly classify the test videos. Further structured education around the LA classification is needed.

Published
2024
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206. SOX2 and PI3K Cooperate to Induce and Stabilize a Squamous-Committed Stem Cell Injury State during Lung Squamous Cell Carcinoma Pathogenesis

Author

Kim, Bo Ram, primary, Van de Laar, Emily, additional, Cabanero, Michael, additional, Tarumi, Shintaro, additional, Hasenoeder, Stefan, additional, Wang, Dennis, additional, Virtanen, Carl, additional, Suzuki, Takaya, additional, Bandarchi, Bizhan, additional, Sakashita, Shingo, additional, Pham, Nhu An, additional, Lee, Sharon, additional, Keshavjee, Shaf, additional, Waddell, Thomas K., additional, Tsao, Ming-Sound, additional, and Moghal, Nadeem, additional

Published
2016
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207. Molecular heterogeneity of non-small cell lung carcinoma patient-derived xenografts closely reflect their primary tumors

Author

Wang, Dennis, primary, Pham, Nhu-An, additional, Tong, Jiefei, additional, Sakashita, Shingo, additional, Allo, Ghassan, additional, Kim, Lucia, additional, Yanagawa, Naoki, additional, Raghavan, Vibha, additional, Wei, Yuhong, additional, To, Christine, additional, Trinh, Quang M., additional, Starmans, Maud H.W., additional, Chan-Seng-Yue, Michelle A., additional, Chadwick, Dianne, additional, Li, Lei, additional, Zhu, Chang-Qi, additional, Liu, Ni, additional, Li, Ming, additional, Lee, Sharon, additional, Ignatchenko, Vladimir, additional, Strumpf, Dan, additional, Taylor, Paul, additional, Moghal, Nadeem, additional, Liu, Geoffrey, additional, Boutros, Paul C., additional, Kislinger, Thomas, additional, Pintilie, Melania, additional, Jurisica, Igor, additional, Shepherd, Frances A., additional, McPherson, John D., additional, Muthuswamy, Lakshmi, additional, Moran, Michael F., additional, and Tsao, Ming-Sound, additional

Published
2016
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208. Identification of Pharmacodynamic Transcript Biomarkers in Response toFGFRInhibition by AZD4547

Author

Delpuech, Oona, primary, Rooney, Claire, additional, Mooney, Lorraine, additional, Baker, Dawn, additional, Shaw, Robert, additional, Dymond, Michael, additional, Wang, Dennis, additional, Zhang, Pei, additional, Cross, Sarah, additional, Veldman-Jones, Margaret, additional, Wilson, Joanne, additional, Davies, Barry R., additional, Dry, Jonathan R., additional, Kilgour, Elaine, additional, and Smith, Paul D., additional

Published
2016
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211. Abstract 4186: Syngenomic fingerprint: the biomic characterization of the mouse syngeneic tumor models

Author

Prime, John E., primary, Mosely, Suzanne, additional, Koopmann, Jens-Oliver, additional, Wang, Dennis YQ, additional, Greenawalt, Danielle, additional, Harper, James, additional, Ahdesmaki, Miika J., additional, Leyland, Rebecca, additional, Harris, Olivia, additional, Stewart, Ross, additional, Brohawn, Philip, additional, Higgs, Brandon, additional, Langford, Bryony, additional, Herath, Athula, additional, Kozarski, Robert, additional, Coates-Ulrichsen, Jane, additional, Anderton, Judith, additional, Morrow, Michelle, additional, Sainson, Richard C. A, additional, and Wilkinson, Robert W., additional

Published
2016
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212. PinchFun

Author

Wang, I-Fang, primary, Wang, Dennis, additional, Chen, Chia-Yu, additional, and Jheng, Jyun-Fong, additional

Published
2016
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215. Breaking into China

Author

Li, Ji, Qian, Gongming, Lam, Kevin, and Wang, Dennis

Subjects
Business -- Research, Business, Business, general, Economics
Abstract

International firms can adopt different strategies when breaking into an emerging market such as China. This article studies three strategic choices facing multinational corporations (MNCs): labour-intensive vs. capital- and technology-intensive; coastal vs. inland location; and joint venture vs. wholly-owned investment. Using hierarchical regression analysis on data from 223 large, foreign-invested electronics firms in China, we offer interesting findings as to how and why different strategies affect the performance of foreign direct investment. We show that MNCs pursuing a capital- and technology-intensive strategy in China have a significantly better performance than those pursuing a labour-intensive strategy. Our study also documents significant interaction effects between ownership arrangements and technology intensity on firm performance. On the other hand, the effect of a firm's location and ownership arrangements appear insignificant. To compete successfully in China today, firms cannot just focus on cheap labour and the production of low value-added goods; a capital- and technology-intensive strategy is more rewarding., International firms can adopt different strategies when breaking into an emerging market such as China. This article studies three strategic choices facing multinational corporations (MNCs): labour-intensive vs. capital- and technology-intensive; coastal vs. inland location; and joint venture vs. wholly-owned investment. Using hierarchical regression analysis on data from 223 large, foreign-invested electronics firms in China, we offer interesting findings as to how and why different strategies affect the performance of foreign direct investment. We show that MNCs pursuing a capital- and technology-intensive strategy in China have a significantly better performance than those pursuing a labour-intensive strategy. Our study also documents significant interaction effects between ownership arrangements and technology intensity on firm performance. On the other hand, the effect of a firm's location and ownership arrangements appear insignificant. To compete successfully in China today, firms cannot just focus on cheap labour and the production of low value-added goods; a capital- and technology-intensive strategy is more rewarding.

Published
2000

218. Clinical Utility of Patient-Derived Xenografts to Determine Biomarkers of Prognosis and Map Resistance Pathways in EGFR-Mutant Lung Adenocarcinoma

Author

Stewart, Erin L., primary, Mascaux, Celine, additional, Pham, Nhu-An, additional, Sakashita, Shingo, additional, Sykes, Jenna, additional, Kim, Lucia, additional, Yanagawa, Naoki, additional, Allo, Ghassan, additional, Ishizawa, Kota, additional, Wang, Dennis, additional, Zhu, Chang-Qi, additional, Li, Ming, additional, Ng, Christine, additional, Liu, Ni, additional, Pintilie, Melania, additional, Martin, Petra, additional, John, Tom, additional, Jurisica, Igor, additional, Leighl, Natasha B., additional, Neel, Benjamin G., additional, Waddell, Thomas K., additional, Shepherd, Frances A., additional, Liu, Geoffrey, additional, and Tsao, Ming-Sound, additional

Published
2015
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220. The Wide-Field Imager for Solar Probe Plus (WISPR)

Author

Vourlidas, Angelos, primary, Howard, Russell A., additional, Plunkett, Simon P., additional, Korendyke, Clarence M., additional, Thernisien, Arnaud F. R., additional, Wang, Dennis, additional, Rich, Nathan, additional, Carter, Michael T., additional, Chua, Damien H., additional, Socker, Dennis G., additional, Linton, Mark G., additional, Morrill, Jeff S., additional, Lynch, Sean, additional, Thurn, Adam, additional, Van Duyne, Peter, additional, Hagood, Robert, additional, Clifford, Greg, additional, Grey, Phares J., additional, Velli, Marco, additional, Liewer, Paulett C., additional, Hall, Jeffrey R., additional, DeJong, Eric M., additional, Mikic, Zoran, additional, Rochus, Pierre, additional, Mazy, Emanuel, additional, Bothmer, Volker, additional, and Rodmann, Jens, additional

Published
2015
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221. Cell surface marker profiling of human tracheal basal cells reveals distinct subpopulations, identifies MST1/MSP as a mitogenic signal, and identifies new biomarkers for lung squamous cell carcinomas

Author

Van de Laar, Emily, primary, Clifford, Monica, additional, Hasenoeder, Stefan, additional, Kim, Bo Ram, additional, Wang, Dennis, additional, Lee, Sharon, additional, Paterson, Josh, additional, Vu, Nancy M, additional, Waddell, Thomas K, additional, Keshavjee, Shaf, additional, Tsao, Ming-Sound, additional, Ailles, Laurie, additional, and Moghal, Nadeem, additional

Published
2014
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224. The relationship between serum uric acid and metabolic syndrome in premenopausal and postmenopausal women in the Jinchang Cohort.

Author

He, Shi-Jiao, Chan, Cynthia, Xie, Zhi-Dong, Shi, Dian, Hu, Xiao-Bin, Li, Hai-Yan, Wang, Dennis, Wang, Min-Zhen, and Bai, Ya-Na

Subjects
URIC acid, METABOLIC syndrome, POSTMENOPAUSE, COHORT analysis, METAL industry, PERIODIC health examinations, EMPLOYEES
Abstract

Copyright of Gynecological Endocrinology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2017
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225. Integrated Omic analysis of lung cancer reveals metabolism proteome signatures with prognostic impact

Author

Li, Lei, primary, Wei, Yuhong, additional, To, Christine, additional, Zhu, Chang-Qi, additional, Tong, Jiefei, additional, Pham, Nhu-An, additional, Taylor, Paul, additional, Ignatchenko, Vladimir, additional, Ignatchenko, Alex, additional, Zhang, Wen, additional, Wang, Dennis, additional, Yanagawa, Naoki, additional, Li, Ming, additional, Pintilie, Melania, additional, Liu, Geoffrey, additional, Muthuswamy, Lakshmi, additional, Shepherd, Frances A., additional, Tsao, Ming Sound, additional, Kislinger, Thomas, additional, and Moran, Michael F., additional

Published
2014
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227. Abstract 1184: Modeling mechanisms of resistance of epidermal growth factor receptor (EGFR) mutations to targeted drugs through patient-derived xenografts (PDX) of non-small cell lung cancer (NSCLC)

Author

Stewart, Erin L., primary, Mascaux, Celine, additional, Shakashita, Shingo, additional, Panchal, Devang, additional, Wang, Dennis, additional, Li, Ming, additional, Pham, Nhu-An, additional, Leighl, Natasha, additional, Liu, Geoffrey, additional, Shepherd, Frances A., additional, and Tsao, Ming-Sound, additional

Published
2014
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229. Role of Macrophage CCAAT/Enhancer Binding Protein Delta in the Pathogenesis of Rheumatoid Arthritis in Collagen-Induced Arthritic Mice

Author

Chang, Ling-Hua, Chang, Ling-Hua, Huang, Huei-Sheng, Wu, Po-Ting, Jou, I-Ming, Pan, Min-Hsiung, Chang, Wen-Chang, Wang, Dennis Ding Hwa, Wang, Ju-Ming, Aprikyan, Andranik Andrew, Chang, Ling-Hua, Chang, Ling-Hua, Huang, Huei-Sheng, Wu, Po-Ting, Jou, I-Ming, Pan, Min-Hsiung, Chang, Wen-Chang, Wang, Dennis Ding Hwa, Wang, Ju-Ming, and Aprikyan, Andranik Andrew

Published
2012

230. Editorial: The Role of Neurovascular Unit in Neurodegeneration.

Author

Zhou, Zhi Dong, Wang, Dennis Qing, and Tan, Eng-King

Subjects
PERICYTES, BLOOD-brain barrier, CEREBRAL circulation, NEURODEGENERATION, BRAIN injuries
Abstract

Keywords: blood-brain barrier; cerebral blood flow; cerebral vasculature system; neurovascular unit (NVU); neurovascular coupling (NC); pathogenesis and therapy EN blood-brain barrier cerebral blood flow cerebral vasculature system neurovascular unit (NVU) neurovascular coupling (NC) pathogenesis and therapy 1 2 2 04/21/22 20220419 NES 220419 The neurovascular unit (NVU) is a novel concept which refers to the dynamic multicellular complex and functional interactions between brain tissues and blood vessels (Schaeffer and Iadecola, [3]). It is suggested that the NVU modulates neurovascular coupling (NVC) and maintains blood-brain barrier (BBB) functions, which are vital to brain homeostasis and functions (Bell et al., [1]). Cerebral vasculature system, pathogenesis and therapy, blood-brain barrier, cerebral blood flow, neurovascular unit (NVU), neurovascular coupling (NC). [Extracted from the article]

Published
2022
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231. Development and test of an active pixel sensor detector for heliospheric imager on solar orbiter and solar probe plus

Author

Korendyke, Clarence M., primary, Vourlidas, Angelos, additional, Plunkett, Simon P., additional, Howard, Russell A., additional, Wang, Dennis, additional, Marshall, Cheryl J., additional, Waczynski, Augustyn, additional, Janesick, James J., additional, Elliott, Thomas, additional, Tun, Samuel, additional, Tower, John, additional, Grygon, Mark, additional, Keller, David, additional, and Clifford, Gregory E., additional

Published
2013
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232. The solar and heliospheric imager (SoloHI) instrument for the solar orbiter mission

Author

Howard, Russell A., primary, Vourlidas, Angelos, additional, Korendyke, Clarence M., additional, Plunkett, Simon P., additional, Carter, Michael T., additional, Wang, Dennis, additional, Rich, Nathan, additional, McMullin, Donald R., additional, Lynch, Sean, additional, Thurn, Adam, additional, Clifford, Greg, additional, Socker, Dennis G., additional, Thernisien, Arnaud F., additional, Chua, Damien, additional, Linton, Mark G., additional, Keller, David, additional, Janesick, James R., additional, Tower, John, additional, Grygon, Mark, additional, Hagood, Robert, additional, Bast, William, additional, Liewer, Paulett C., additional, DeJong, Eric M., additional, Velli, Marco M. C., additional, Mikic, Zoran, additional, Bothmer, Volker, additional, Rochus, Pierre, additional, Halain, Jean-Philippe, additional, and Lamy, Philippe L., additional

Published
2013
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235. CCAAT/Enhancer Binding Protein δ in Macrophages Contributes to Immunosuppression and Inhibits Phagocytosis in Nasopharyngeal Carcinoma

Author

Hsiao, Yu-Wei, primary, Li, Chien-Feng, additional, Chi, Jhih-Ying, additional, Tseng, Joseph T., additional, Chang, Yao, additional, Hsu, Li-Jin, additional, Lee, Chien-Hsun, additional, Chang, Tsung-Hao, additional, Wang, Shao-Ming, additional, Wang, Dennis Ding Hwa, additional, Cheng, Hung-Chi, additional, and Wang, Ju-Ming, additional

Published
2013
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239. Polymorphisms in complement genes and risk of preeclampsia in Taiyuan, China.

Author

Wu, Weiwei, Yang, Hailan, Feng, Yongliang, Zhang, Ping, Li, Shuzhen, Wang, Xin, Peng, Tingting, Wang, Fang, Xie, Bingjie, Guo, Pengge, Li, Mei, Wang, Ying, Zhao, Nan, Wang, Dennis, Wang, Suping, and Zhang, Yawei

Subjects
RISK factors of preeclampsia, IMMUNE response, EPIDEMIOLOGY, GENETIC polymorphisms, PREECLAMPSIA, GENETICS
Abstract

Altered immune response may be a part of the pathogenesis of preeclampsia. The few epidemiologic studies that have investigated the associations between genetic variations in the complement system genes and preeclampsia risk have reached inconsistent results. The aim of this study is to determine if polymorphisms in the complement system genes could influence the risk of preeclampsia. Methods: We examined 51 SNPs in the C3, C5, C6, MASP1, MBL2 and CD55 genes and the risk of preeclampsia and its clinical subtypes in a nested case-control study of 203 preeclampsia cases and 233 controls. Results: Both C6 and MASP1 were associated with the risk of preeclampsia. C6 (rs7444800, rs4957381) and MASP1 (rs1108450, rs3774282, rs698106) polymorphisms were associated with the risk of early-onset preeclampsia and severe preeclampsia, while MASP1 (rs1357134, rs698090) polymorphisms were associated with the risk of late-onset preeclampsia and severe preeclampsia. Conclusions: Our study provided novel evidence that genetic variations in complement genes C6 and MASP1were associated with preeclampsia risk, and that the risk varied by preeclampsia subtypes. [ABSTRACT FROM AUTHOR]

Published
2016
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240. Interaction between HCMV infection and PAX9 gene polymorphisms in low birth weight infants.

Author

Cheng, Ning, Wang, Dennis, Zhou, Zhihui, Cheng, Zhiyuan, Dong, Li, Zhang, Rongqiang, Zhang, Yawei, Zheng, Tongzhang, and Bai, Yana

Subjects
*HUMAN cytomegalovirus diseases, *GENETIC polymorphism research, *LOW birth weight, *MOLECULAR epidemiology, *POLYMERASE chain reaction, *COMPARATIVE studies, *CYTOMEGALOVIRUS diseases, *GENETIC polymorphisms, *RESEARCH methodology, *MEDICAL cooperation, *PROTEINS, *RESEARCH, *EVALUATION research, *CASE-control method
Abstract

Objective: To investigate the interaction between human cytomegalovirus infection and PAX9 gene polymorphisms in low birth weight (LBW) infants.Methods: Nested-PCR was used to detect human cytomegalovirus (HCMV) infection and restriction fragment length polymorphism PCR (RFLP-PCR) was then used to detect polymorphisms at rs2073244 and rs4904210 on the PAX9 gene in 65 HCMV-positive infant cases and 65 HCMV-negative infant controls. Cases and controls were compared for differences in the rates of LBW using the χ(2) test. Genetic and environmental interactions were assessed by comparing rates of LBW between the cases and controls in stratified analyses and logistic regressions.Results: The study confirmed that HCMV infection is significantly associated with LBW (OR = 5.519, χ(2) = 20.924, p < 0.05) and suggested that some PAX9 polymorphisms may promote the induction of LBW by HCMV infection. The AG and GG genotypes at rs2073244 and the CC genotype at rs4904210, with interaction coefficients greater than unity suggest that they may strengthen the association between HCMV infection and LBW.Conclusions: Congenital HCMV infection can cause LBW and some PAX9 polymorphisms can increase the risk of LBW in HCMV-infected infants. The results may provide new clues into the relationship among HCMV infection, PAX9 polymorphisms and LBW as well as a foundation for additional molecular epidemiological and biochemical research in the future. [ABSTRACT FROM AUTHOR]

Published
2016
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241. Prevalence and mortality of cancer among HIV-infected inpatients in Beijing, China.

Author

Jun Yang, Shu Su, Hongxin Zhao, Dennis Wang, Jiali Wang, Fujie Zhang, Yan Zhao, Yang, Jun, Su, Shu, Zhao, Hongxin, Wang, Dennis, Wang, Jiali, Zhang, Fujie, and Zhao, Yan

Subjects
CANCER-related mortality, DISEASE prevalence, HIV-positive persons, CANCER risk factors research, ANTIRETROVIRAL agents, HIV infection complications, HOSPITAL care, LONGITUDINAL method, TUMORS, LOGISTIC regression analysis, PROPORTIONAL hazards models, RETROSPECTIVE studies, KAPLAN-Meier estimator
Abstract

Background: Cancer is responsible for elevated HIV-related morbidity and mortality. Research on HIV-infected patients with concurrent cancer is rare in China. The purpose of our study was to investigate the prevalence and risk factors associated with cancer among HIV-infected inpatients in Beijing, and to investigate the mortality and risk factors among HIV-infected inpatients with cancer.Methods: Hospital records from a total of 1946 HIV-infected patients were collected from the Beijing Ditan Hospital. The data, from 2008 to 2013, were collected retrospectively. The cancer diagnoses included AIDS-defining cancers (ADC) and non-AIDS defining cancers (NADC). Logistic regression was used to identify risk factors predicting the concurrence of cancer with HIV. Mortality was examined using Kaplan-Meier estimates and Cox proportional hazards models.Results: 7.7 % (149 cases) of all HIV-infected inpatients had concurrent cancer at their first hospital admission; of those, 33.6 % (50 cases) had ADCs, and 66.4 % (99 cases) had NADCs. The most prevalent NADCs were Hodgkin's lymphoma, gastrointestinal cancer, liver cancer, and lung cancer. Patients who did not accept antiretroviral therapy (ART) were more likely to suffer from cancer [AOR = 2.07 (1.42-3.01), p = 0.001]. Kaplan-Meier curves indicated that the survival probability of HIV-positive cancer patients was significantly lower than that of HIV-positive cancer-free patients (log-rank test, p < 0.001). For patients diagnosed with cancer, the mortality was also higher among those who did not receive ART [AHR = 2.19 (1.84-2.61), p < 0.001].Conclusion: The prevalence of cancer concurrence among hospitalized HIV-infected patients was 7.7 %. Concurrent cancer also increased mortality among HIV-infected patients. ART was protective against concurrent cancer as well as mortality among HIV-infected cancer patients. These results highlight the importance of promoting cancer screening and early ART initiation among HIV-infected patients. [ABSTRACT FROM AUTHOR]

Published
2016
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244. Role of dopamine in the pathophysiology of Parkinson's disease.

Author

Zhou, Zhi Dong, Yi, Ling Xiao, Wang, Dennis Qing, Lim, Tit Meng, and Tan, Eng King

Subjects
*PARKINSON'S disease, *DOPAMINERGIC neurons, *DOPAMINE, *PATHOLOGICAL physiology, *REACTIVE oxygen species
Abstract

A pathological feature of Parkinson's disease (PD) is the progressive loss of dopaminergic neurons and decreased dopamine (DA) content in the substantia nigra pars compacta in PD brains. DA is the neurotransmitter of dopaminergic neurons. Accumulating evidence suggests that DA interacts with environmental and genetic factors to contribute to PD pathophysiology. Disturbances of DA synthesis, storage, transportation and metabolism have been shown to promote neurodegeneration of dopaminergic neurons in various PD models. DA is unstable and can undergo oxidation and metabolism to produce multiple reactive and toxic by-products, including reactive oxygen species, DA quinones, and 3,4-dihydroxyphenylacetaldehyde. Here we summarize and highlight recent discoveries on DA-linked pathophysiologic pathways, and discuss the potential protective and therapeutic strategies to mitigate the complications associated with DA. [ABSTRACT FROM AUTHOR]

Published
2023
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245. Bilateral treatment of the masseter with botulinum toxin: Consequences for mastication, muscle force and the mandibular condyle.

Author

Liu, Zi‐Jun, Rafferty, Katherine L., Wang, Dennis B., Owart, Birkin, and Herring, Susan W.

Subjects
*BOTULINUM toxin, *MANDIBULAR condyle, *BODY weight, *PTERYGOID muscles, *MASTICATORY muscles, *ANIMAL experimentation, *MASSETER muscle, *RABBITS, *DIET, *DENTAL occlusion, *COMPARATIVE studies, *MASTICATION, *RESEARCH funding, *WEIGHT loss, *BONE density, *ELECTROMYOGRAPHY, *COMPUTED tomography
Abstract

Background: Clinical use of botulinum neurotoxins (BoNTs) in masticatory muscles is usually bilateral, but most studies on the functional consequences of BoNT treatment have used unilaterally treated animals. Objectives: To test the hypothesis that bilateral BoNT treatment of the rabbit masseter hampers mastication and to assess its effects on bone density of the mandibular condyles. Methods: Ten 5‐month‐old female rabbits received injections of BoNT into both masseter muscles and nine sham animals received saline. Body weight, incisor bite force during masseter tetany, and surface and fine‐wire electromyography (EMG) of the masseter and medial pterygoid muscles were assessed at regular intervals. Half the sample was terminated after 4 weeks and the remainder after 12 weeks. Muscles were weighed and mandibular condyles were scanned with microCT to analyse bone density. Results: BoNT rabbits lost weight and required a soft‐food diet. Incisor occlusal force plummeted after BoNT injection and remained lower than the shams. The duration of masticatory cycles was increased in the BoNT rabbits for 5 weeks, with most of the increase due to the adductor burst. Masseteric EMG amplitude began to improve at Week 5, but remained low on the working side throughout the experiment. At the 12‐week endpoint, masseter muscles were smaller in the BoNT rabbits. Medial pterygoid muscles did not compensate. Condylar bone density was reduced. Conclusion: Bilateral treatment of the rabbit masseter by BoNT severely affected chewing performance. Even after a 3‐month recovery period, deficits remained in bite force, muscle size and condylar bone density. [ABSTRACT FROM AUTHOR]

Published
2023
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