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Pfeifer W. Managing Pediatric Cataract Patients: Amblyopia Treatment and Binocularity Outcomes. J Binocul Vis Ocul Motil 2023; 73:109-114. [PMID: 37931117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
Unilateral congenital cataracts present multiple barriers in the development of vision and stereoacuity despite the improved visual optics that early surgery, contact lenses and intraocular lenses (IOL) have provided. With better understanding of the latent period (the timeframe in which the abnormal event has no long-term effect on visual development in the deprived eye) and the critical periods (the age range during which developing brains can be altered in a profound and permanent way by abnormal experience) for stereoacuity and amblyopia we can focus our treatment methods to not only improve vision but also develop binocularity. Fifty years ago, it was believed that it was almost impossible for an eye with a unilateral congenital cataract to achieve good visual acuity. Twenty-five years ago, we believed that it was almost impossible for an eye with a unilateral cataract to achieve stereoacuity. It is time to expand our belief that the best that we can do with the eye in unilateral congenital cataract is to create a spare.
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Affiliation(s)
- Wanda Pfeifer
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA
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Liu Q, Sun T, Wen X, Zeng M, Chen J. Detecting the Minimum Limit on Wheat Stripe Rust in the Latent Period Using Proximal Remote Sensing Coupled with Duplex Real-Time PCR and Machine Learning. Plants (Basel) 2023; 12:2814. [PMID: 37570968 PMCID: PMC10420842 DOI: 10.3390/plants12152814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/27/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023]
Abstract
Wheat stripe rust (WSR) is an airborne disease that causes severe damage to wheat. The rapid and early detection of WSR is essential for the prevention and control of this disease. The minimum detection limit (MDL) is one of the most important characteristics of quantitative methods that can be used to determine the scope and applicability of a measurement technique. Three wheat cultivars were inoculated with Puccinia striiformis f.sp. tritici (Pst), and a spectrometer was used to collect the canopy hyperspectral data, and the Pst content was obtained via a duplex real-time polymerase chain reaction (PCR) during the latent period, respectively. The disease index (DI) and molecular disease index (MDI) were calculated. The regression tree algorithm was used to determine the MDL of the Pst based on hyperspectral feature parameters. The logistic, IBK, and random committee algorithms were used to construct the classification model based on the MDL. The results showed that when the MDL was 0.7, IBK had the best recognition accuracy. The optimal model, which used the spectral feature R_2nd.dv ((the second derivative of the original hyperspectral value)) and the modeling ratio 2:1, had an accuracy of 91.67% on the testing set and 90.67% on the 10-fold cross-validation. Thus, during the latent period, the MDL of Pst was determined using hyperspectral technology as 0.7.
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Affiliation(s)
- Qi Liu
- Key Laboratory of the Pest Monitoring and Safety Control of Crops and Forests of the Xinjiang Uygur Autonomous Region, College of Agronomy, Xinjiang Agricultural University, Urumqi 830052, China; (T.S.)
- Key Laboratory of Prevention and Control of Invasive Alien Species in Agriculture & Forestry of the North-Western Desert Oasis, Ministry of Agriculture and Rural Affairs, Urumqi 830052, China
| | - Tingting Sun
- Key Laboratory of the Pest Monitoring and Safety Control of Crops and Forests of the Xinjiang Uygur Autonomous Region, College of Agronomy, Xinjiang Agricultural University, Urumqi 830052, China; (T.S.)
- Key Laboratory of Prevention and Control of Invasive Alien Species in Agriculture & Forestry of the North-Western Desert Oasis, Ministry of Agriculture and Rural Affairs, Urumqi 830052, China
| | - Xiaojie Wen
- Key Laboratory of the Pest Monitoring and Safety Control of Crops and Forests of the Xinjiang Uygur Autonomous Region, College of Agronomy, Xinjiang Agricultural University, Urumqi 830052, China; (T.S.)
- Key Laboratory of Prevention and Control of Invasive Alien Species in Agriculture & Forestry of the North-Western Desert Oasis, Ministry of Agriculture and Rural Affairs, Urumqi 830052, China
| | - Minghao Zeng
- Key Laboratory of the Pest Monitoring and Safety Control of Crops and Forests of the Xinjiang Uygur Autonomous Region, College of Agronomy, Xinjiang Agricultural University, Urumqi 830052, China; (T.S.)
- Key Laboratory of Prevention and Control of Invasive Alien Species in Agriculture & Forestry of the North-Western Desert Oasis, Ministry of Agriculture and Rural Affairs, Urumqi 830052, China
| | - Jing Chen
- Key Laboratory of the Pest Monitoring and Safety Control of Crops and Forests of the Xinjiang Uygur Autonomous Region, College of Agronomy, Xinjiang Agricultural University, Urumqi 830052, China; (T.S.)
- Key Laboratory of Prevention and Control of Invasive Alien Species in Agriculture & Forestry of the North-Western Desert Oasis, Ministry of Agriculture and Rural Affairs, Urumqi 830052, China
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Kim T, Lee H, Kim S, Kim C, Son H, Lee S. Improved time-varying reproduction numbers using the generation interval for COVID-19. Front Public Health 2023; 11:1185854. [PMID: 37457248 PMCID: PMC10348824 DOI: 10.3389/fpubh.2023.1185854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 06/08/2023] [Indexed: 07/18/2023] Open
Abstract
Estimating key epidemiological parameters, such as incubation period, serial interval (SI), generation interval (GI) and latent period, is essential to quantify the transmissibility and effects of various interventions of COVID-19. These key parameters play a critical role in quantifying the basic reproduction number. With the hard work of epidemiological investigators in South Korea, estimating these key parameters has become possible based on infector-infectee surveillance data of COVID-19 between February 2020 and April 2021. Herein, the mean incubation period was estimated to be 4.9 days (95% CI: 4.2, 5.7) and the mean generation interval was estimated to be 4.3 days (95% CI: 4.2, 4.4). The mean serial interval was estimated to be 4.3, with a standard deviation of 4.2. It is also revealed that the proportion of presymptomatic transmission was ~57%, which indicates the potential risk of transmission before the disease onset. We compared the time-varying reproduction number based on GI and SI and found that the time-varying reproduction number based on GI may result in a larger estimation of Rt, which refers to the COVID-19 transmission potential around the rapid increase of cases. This highlights the importance of considering presymptomatic transmission and generation intervals when estimating the time-varying reproduction number.
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Affiliation(s)
- Tobhin Kim
- Department of Applied Mathematics, Kyung Hee University, Yongin, Republic of Korea
| | - Hyojung Lee
- Department of Statistics, Kyungpook National University, Daegu, Republic of Korea
| | - Sungchan Kim
- Department of Applied Mathematics, Kyung Hee University, Yongin, Republic of Korea
| | - Changhoon Kim
- Department of Preventive Medicine, College of Medicine, Pusan National University, Busan, Republic of Korea
- Busan Center for Infectious Disease Control and Prevention, Pusan National University Hospital, Busan, Republic of Korea
| | - Hyunjin Son
- Busan Center for Infectious Disease Control and Prevention, Pusan National University Hospital, Busan, Republic of Korea
- Department of Preventive Medicine, College of Medicine, Dong-A University, Busan, Republic of Korea
| | - Sunmi Lee
- Department of Applied Mathematics, Kyung Hee University, Yongin, Republic of Korea
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Yang J, Wang X, Li K. Temporal-spatial analysis of a foot-and-mouth disease model with spatial diffusion and vaccination. Front Vet Sci 2022; 9:952382. [PMID: 36544556 PMCID: PMC9760958 DOI: 10.3389/fvets.2022.952382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 11/16/2022] [Indexed: 12/07/2022] Open
Abstract
Foot-and-mouth disease is an acute, highly infectious, and economically significant transboundary animal disease. Vaccination is an efficient and cost-effective measure to prevent the transmission of this disease. The primary way that foot-and-mouth disease spreads is through direct contact with infected animals, although it can also spread through contact with contaminated environments. This paper uses a diffuse foot-and-mouth disease model to account for the efficacy of vaccination in managing the disease. First, we transform an age-space structured foot-and-mouth disease into a diffusive epidemic model with nonlocal infection coupling the latent period and the latent diffusive rate. The basic reproduction number, which determines the outbreak of the disease, is then explicitly formulated. Finally, numerical simulations demonstrate that increasing vaccine efficacy has a remarkable effect than increasing vaccine coverage.
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Affiliation(s)
- Junyuan Yang
- Complex Systems Research Center, Shanxi University, Taiyuan, China,Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention, Shanxi University, Taiyuan, China,*Correspondence: Junyuan Yang
| | - Xiaoyan Wang
- School of Information, Shanxi University of Finance and Economics, Taiyuan, China
| | - Kelu Li
- School of Mathematics and Information Science, Henan Normal University, Xinxiang, China
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Ma T, Ding S, Huang R, Wang H, Wang J, Liu J, Wang J, Li J, Wu C, Fan H, Zhou N. The latent period of coronavirus disease 2019 with SARS-CoV-2 B.1.617.2 Delta variant of concern in the postvaccination era. Immun Inflamm Dis 2022; 10:e664. [PMID: 35759239 PMCID: PMC9186332 DOI: 10.1002/iid3.664] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/27/2022] [Accepted: 05/28/2022] [Indexed: 12/01/2022] Open
Abstract
Introduction Emerging variants of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) have resulted in new challenges for epidemic prevention and control worldwide. However, little is known about the latent period of coronavirus disease by the SARS‐CoV‐2 Delta variant of concern (VOC) in the postvaccination era. Methods The epidemiology and clinical data of cases with confirmed SARS‐CoV‐2 Delta VOC infection were retrospective collected. Dates of the first positive PCR test were collected to estimate the distribution of latent period. Results Of the 40 patients, 16 were male (40%). The median age of patients was 47.5 years. The median latent period of patients was 6.0 days (interquartile range [IQR], 4.0−9.0 days) and the longest latent period was 13.0 days after exposure. The latent periods were longer in male patients compared to female patients (median, 8.5 days vs. 5.0 days, p = .041). The median latent period was comparable among fully vaccinated cases (6.5 days), no vaccinated cases (7.5 days), and partially vaccinated cases (5.5 days). Conclusions The median latent period of SARS‐CoV‐2 Delta VOC infection was 6.0 days. The latent period between vaccinated and non‐vaccinated patients was not significantly different. The 14‐day quarantine program is sufficient to prevent the transmission of COVID‐19 by Delta VOC in the postvaccination era.
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Affiliation(s)
- Tao Ma
- Department of Acute Infectious Disease Control and Prevention, Nanjing Municipal Center for Disease Control and Prevention, Nanjing, China
| | - Songning Ding
- Department of Acute Infectious Disease Control and Prevention, Nanjing Municipal Center for Disease Control and Prevention, Nanjing, China
| | - Rui Huang
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Hengxue Wang
- Department of Acute Infectious Disease Control and Prevention, Nanjing Municipal Center for Disease Control and Prevention, Nanjing, China
| | - Junjun Wang
- Department of Acute Infectious Disease Control and Prevention, Nanjing Municipal Center for Disease Control and Prevention, Nanjing, China
| | - Jiacheng Liu
- Department of Infectious Diseases, Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
| | - Jian Wang
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Jie Li
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Chao Wu
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Huafeng Fan
- Microbiology Laboratory, Nanjing Municipal Center for Disease Control and Prevention, Nanjing, China
| | - Nan Zhou
- Department of Acute Infectious Disease Control and Prevention, Nanjing Municipal Center for Disease Control and Prevention, Nanjing, China
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Hwang Y, Kadam SD. Targeting Epileptogenesis: A Conceptual Black Hole or Light at the End of the Tunnel? Epilepsy Curr 2021; 21:372-375. [PMID: 34924840 PMCID: PMC8655252 DOI: 10.1177/15357597211030384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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Mokhothu TM, Tanaka KZ. Characterizing Hippocampal Oscillatory Signatures Underlying Seizures in Temporal Lobe Epilepsy. Front Behav Neurosci 2021; 15:785328. [PMID: 34899205 PMCID: PMC8656355 DOI: 10.3389/fnbeh.2021.785328] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 10/29/2021] [Indexed: 01/01/2023] Open
Abstract
Temporal Lobe Epilepsy (TLE) is a neurological condition characterized by focal brain hyperexcitability, resulting in abnormal neuronal discharge and uncontrollable seizures. The hippocampus, with its inherently highly synchronized firing patterns and relatively high excitability, is prone to epileptic seizures, and it is usually the focus of TLE. Researchers have identified hippocampal high-frequency oscillations (HFOs) as a salient feature in people with TLE and animal models of this disease, arising before or at the onset of the epileptic event. To a certain extent, these pathological HFOs have served as a marker and a potential target for seizure attenuation using electrical or optogenetic interventions. However, many questions remain about whether we can reliably distinguish pathological from non-pathological HFOs and whether they can tell us about the development of the disease. While this would be an arduous task to perform in humans, animal models of TLE provide an excellent opportunity to study the characteristics of HFOs in predicting how epilepsy evolves. This minireview will (1) summarize what we know about the oscillatory disruption in TLE, (2) summarize knowledge about oscillatory changes in the latent period and their role in predicting seizures, and (3) propose future studies essential to uncovering potential treatments based on early detection of pathological HFOs.
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Affiliation(s)
- Thato Mary Mokhothu
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Kazumasa Zen Tanaka
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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Kwon SC, Lee SS, Kang MS, Huh DA, Lee YJ. The Epidemiologic Characteristics of Malignant Mesothelioma Cases in Korea: Findings of the Asbestos Injury Relief System from 2011-2015. Int J Environ Res Public Health 2021; 18:10007. [PMID: 34639307 DOI: 10.3390/ijerph181910007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/17/2021] [Accepted: 09/20/2021] [Indexed: 11/25/2022]
Abstract
(1) Background: The purpose of this study was to investigate the epidemiological characteristics of malignant mesothelioma in Korea by investigating cases compensated under the asbestos injury relief system. (2) Methods: A total of 407 compensated cases between 2011 and 2015 were reviewed using medical records and resident registrations in order to investigate the dates of diagnosis and death. Asbestos exposure and patients’ general characteristics were investigated through face-to-face interviews. The standardized incidence ratio was calculated as the number of observations from 2005 to 2014 per exposure region in Korea, using the mid-annual population of each region in 2009 as the standard population. (3) Results: Among the 407 cases, 65.1% were male. The pleura and peritoneum were affected in 76.9% and 23.1% of cases, respectively. For peritoneal mesothelioma, the median survival duration was longer (p = 0.005), and the proportion of affected women was higher than that in pleural mesothelioma. The standardized incidence ratio (95% CI) by province of primary exposure was Chungnam 3.33 (2.51–4.35), Ulsan 1.85 (0.97–3.21), and Seoul 1.32 (1.06–1.63). (4) Conclusions: Although the representativeness of the data is limited, it is sufficient to assume the epidemiologic characteristics of malignant mesothelioma, help improve the compensation system, and contribute to future policies.
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Xin H, Li Y, Wu P, Li Z, Lau EHY, Qin Y, Wang L, Cowling BJ, Tsang T, Li Z. Estimating the latent period of coronavirus disease 2019 (COVID-19). Clin Infect Dis 2021; 74:1678-1681. [PMID: 34453527 DOI: 10.1093/cid/ciab746] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Indexed: 01/12/2023] Open
Abstract
Using detailed exposure information on COVID-19 cases, we estimated the mean latent period to be 5.5 days (95% confidence interval: 5.1-5.9 days), shorter than the mean incubation period (6.9 days). Laboratory testing may allow shorter quarantines since 95% of COVID-19 cases shed virus within 10.6 days (95%CI: 9.6-11.6) of infection.
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Affiliation(s)
- Hualei Xin
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Yu Li
- Division of Infectious Disease, Key Laboratory of Surveillance and Early Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Peng Wu
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.,Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong Special Administrative Region, China
| | - Zhili Li
- Division of Infectious Disease, Key Laboratory of Surveillance and Early Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Eric H Y Lau
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.,Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong Special Administrative Region, China
| | - Ying Qin
- Division of Infectious Disease, Key Laboratory of Surveillance and Early Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Liping Wang
- Division of Infectious Disease, Key Laboratory of Surveillance and Early Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Benjamin J Cowling
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.,Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong Special Administrative Region, China
| | - Tim Tsang
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Zhongjie Li
- Division of Infectious Disease, Key Laboratory of Surveillance and Early Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China
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Abstract
In susceptible-exposed-infectious-recovered (SEIR) epidemic models, with the exponentially distributed duration of exposed/infectious statuses, the mean generation interval (GI, time lag between infections of a primary case and its secondary case) equals the mean latent period (LP) plus the mean infectious period (IP). It was widely reported that the GI for COVID-19 is as short as 5 days. However, many works in top journals used longer LP or IP with the sum (i.e., GI), e.g., >7 days. This discrepancy will lead to overestimated basic reproductive number and exaggerated expectation of infection attack rate (AR) and control efficacy. We argue that it is important to use suitable epidemiological parameter values for proper estimation/prediction. Furthermore, we propose an epidemic model to assess the transmission dynamics of COVID-19 for Belgium, Israel, and the United Arab Emirates (UAE). We estimated a time-varying reproductive number [R0(t)] based on the COVID-19 deaths data and we found that Belgium has the highest AR followed by Israel and the UAE.
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Affiliation(s)
- Xiujuan Tang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Salihu S. Musa
- Department of Applied Mathematics, The Hong Kong Polytechnic University, Hong Kong, China
- Department of Mathematics, Kano University of Science and Technology, Wudil, Nigeria
| | - Shi Zhao
- The Jockey Club School of Public Health and Primary Care, Chinese University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute of Chinese University of Hong Kong, Shenzhen, China
| | - Shujiang Mei
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Daihai He
- Department of Applied Mathematics, The Hong Kong Polytechnic University, Hong Kong, China
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İflazoğlu N, Eroğlu H, Tolunay HE, Yücel A. Comparison of the maternal serum endocan levels in preterm premature rupture of membrane and normal pregnancy. J Obstet Gynaecol Res 2021; 47:3151-3158. [PMID: 34109715 DOI: 10.1111/jog.14836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 04/23/2021] [Accepted: 05/03/2021] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Endocan is a novel marker of endothelial inflammation. In this study, we aimed to show whether there was a significant difference between the endocan levels of pregnant women with and without preterm premature rupture of membranes (PPROM and non-PPROM). Also, we aimed to find a relation between endocan levels and the latent period. MATERIAL AND METHODS Pregnant women with PPROM between 28 and 34 weeks of gestation and those without PPROM with similar gestational weeks were included in the study. A total of 88 pregnant women, 44 with PROM and 44 healthy pregnancies, were evaluated. Demographic and obstetric features, leukocyte, and endocan levels of the study and control groups were compared. RESULTS The demographic features and obstetric history of both groups were similar. The mean leukocyte and endocan levels of the study group were higher than in the control group (p < 0.001 and 0.029, respectively). The leukocyte level was the only independent factor predicting PPROM after multivariate logistic regression analysis. CONCLUSION Although the endocan levels were higher in patients with PPROM, multivariate analysis showed that the only independent predictive factor was the leukocyte level.
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Affiliation(s)
- Nuray İflazoğlu
- Department of Perinatology, Etlik Zübeyde Hanım Maternity and Women's Health Teaching and Research Hospital, Ankara, Turkey
| | - Hasan Eroğlu
- Department of Perinatology, Etlik Zübeyde Hanım Maternity and Women's Health Teaching and Research Hospital, Ankara, Turkey
| | - Harun Egemen Tolunay
- Department of Perinatology, Etlik Zübeyde Hanım Maternity and Women's Health Teaching and Research Hospital, Ankara, Turkey
| | - Aykan Yücel
- Department of Perinatology, Etlik Zübeyde Hanım Maternity and Women's Health Teaching and Research Hospital, Ankara, Turkey
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Kao HY, Hu S, Mihaylova T, Ziobro J, Ahn E, Fine C, Brang D, Watson BO, Wang Y. Defining the latent period of epileptogenesis and epileptogenic zone in a focal cortical dysplasia type II (FCDII) rat model. Epilepsia 2021; 62:1268-1279. [PMID: 33735460 PMCID: PMC8211029 DOI: 10.1111/epi.16868] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 12/14/2022]
Abstract
Objectives Focal cortical dysplasia type II (FCDII) is one of the most common underlying pathologies in patients with drug‐resistant epilepsy. However, mechanistic understanding of FCDII fails to keep pace with genetic discoveries, primarily due to the significant challenge in developing a clinically relevant animal model. Conceptually and clinically important questions, such as the unknown latent period of epileptogenesis and the controversial epileptogenic zone, remain unknown in all experimental FCDII animal models, making it even more challenging to investigate the underlying epileptogenic mechanisms. Methods In this study, we used continuous video‐electroencephalography (EEG) monitoring to detect the earliest interictal and ictal events in a clustered regularly interspaced short palindromic repeats (CRISPR)‐in utero electroporation (IUE) FCDII rat model that shares genetic, pathological, and electroclinical signatures with those observed in humans. We then took advantage of in vivo local field potential (LFP) recordings to localize the epileptogenic zone in these animals. Results To the best of our knowledge, we showed for the first time that epileptiform discharges emerged during the third postnatal week, and that the first seizure occurred as early as during the fourth postnatal week. We also showed that both interictal and ictal discharges are localized within the dysplastic cortex, concordant with human clinical data. Significance Together, our work identified the temporal and spatial frame of epileptogenesis in a highly clinically relevant FCDII animal model, paving the way for mechanistic studies at molecular, cellular, and circuitry levels.
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Affiliation(s)
- Hsin-Yi Kao
- Department of Neurology, University of Michigan, Ann Arbor, USA
| | - Shuntong Hu
- Department of Neurology, University of Michigan, Ann Arbor, USA.,Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China
| | | | - Julie Ziobro
- Department of Pediatrics, University of Michigan, Ann Arbor, USA
| | - EunSeon Ahn
- Department of Psychology, University of Michigan, Ann Arbor, USA
| | - Carli Fine
- Department of Psychology, University of Michigan, Ann Arbor, USA
| | - David Brang
- Department of Psychology, University of Michigan, Ann Arbor, USA
| | - Brendon O Watson
- Department of Psychiatry, University of Michigan, Ann Arbor, USA.,Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, USA
| | - Yu Wang
- Department of Neurology, University of Michigan, Ann Arbor, USA
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Rahman A, Doohan F, Mullins E. Quantification of In Planta Zymoseptoria tritici Progression Through Different Infection Phases and Related Association with Components of Aggressiveness. Phytopathology 2020; 110:1208-1215. [PMID: 32133920 DOI: 10.1094/phyto-09-19-0339-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In planta growth of Zymoseptoria tritici, causal agent of Septoria tritici blotch of wheat, during the infection process has remained an understudied topic due to the long symptomless latent period before the emergence of fruiting bodies. In this study, we attempted to understand the relationship between in planta growth of Z. tritici relative to the primary components of aggressiveness, i.e., latent period and pycnidia coverage in regard to contrasting host resistance. We tested isolates collected from Ireland against the susceptible cultivar Gallant and cultivar Stigg, which has strong partial resistance. A clear isolate-host interaction effect (F = 3.018; P = 0.005, and F = 6.008; P < 0.001) for latent period and pycnidia coverage, respectively, was identified. Furthermore, during the early infection phase of latency from 5 to 11 days postinoculation (dpi), in planta growth rate of fungal biomass was significantly (F = 30.06; P < 0.001) more affected by host resistance than isolate specificity (F = 1.27; P = 0.27), indicating the importance of host resistance in the early infection phase. In planta Z. tritici growth rates in cultivar Gallant spiked between 11 and 16 dpi followed by a continuous fall onward, whereas in cultivar Stigg it was slowly progressive in nature. From correlation and regression analysis, we found that the in planta growth rate preceding the average latent period of cultivar Gallant has more influence on latency duration and pycnidia production. Likewise, correlation between component of aggressiveness and in planta growth rate of pathogen supports our understanding of aggressiveness to be driven by the pathogen's multiplication capacity within host tissue.
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Affiliation(s)
- Atikur Rahman
- Crop Science Department, Teagasc, Oakpark, Carlow, R93 XE12, Ireland
- School of Biological and Environmental Sciences, UCD Earth Institute and UCD Institute of Food and Health, University College of Dublin, Dublin, D04 V1W8, Ireland
| | - Fiona Doohan
- School of Biological and Environmental Sciences, UCD Earth Institute and UCD Institute of Food and Health, University College of Dublin, Dublin, D04 V1W8, Ireland
| | - Ewen Mullins
- Crop Science Department, Teagasc, Oakpark, Carlow, R93 XE12, Ireland
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14
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Getz WM, Salter R, Mgbara W. Adequacy of SEIR models when epidemics have spatial structure: Ebola in Sierra Leone. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180282. [PMID: 31056043 DOI: 10.1098/rstb.2018.0282] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Dynamic SEIR (Susceptible, Exposed, Infectious, Removed) compartmental models provide a tool for predicting the size and duration of both unfettered and managed outbreaks-the latter in the context of interventions such as case detection, patient isolation, vaccination and treatment. The reliability of this tool depends on the validity of key assumptions that include homogeneity of individuals and spatio-temporal homogeneity. Although the SEIR compartmental framework can easily be extended to include demographic (e.g. age) and additional disease (e.g. healthcare workers) classes, dependence of transmission rates on time, and metapopulation structure, fitting such extended models is hampered by both a proliferation of free parameters and insufficient or inappropriate data. This raises the question of how effective a tool the basic SEIR framework may actually be. We go some way here to answering this question in the context of the 2014-2015 outbreak of Ebola in West Africa by comparing fits of an SEIR time-dependent transmission model to both country- and district-level weekly incidence data. Our novel approach in estimating the effective-size-of-the-populations-at-risk ( Neff) and initial number of exposed individuals ( E0) at both district and country levels, as well as the transmission function parameters, including a time-to-halving-the-force-of-infection ( tf/2) parameter, provides new insights into this Ebola outbreak. It reveals that the estimate R0 ≈ 1.7 from country-level data appears to seriously underestimate R0 ≈ 3.3 - 4.3 obtained from more spatially homogeneous district-level data. Country-level data also overestimate tf/2 ≈ 22 weeks, compared with 8-10 weeks from district-level data. Additionally, estimates for the duration of individual infectiousness is around two weeks from spatially inhomogeneous country-level data compared with 2.4-4.5 weeks from spatially more homogeneous district-level data, which estimates are rather high compared with most values reported in the literature. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'. This issue is linked with the subsequent theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'.
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Affiliation(s)
- Wayne M Getz
- 1 Department Environmental Science, Policy and Management, University of California , Berkeley, CA 94708-3112 , USA.,2 School of Mathematical Sciences, University of KwaZulu-Natal , Durban , South Africa
| | | | - Whitney Mgbara
- 1 Department Environmental Science, Policy and Management, University of California , Berkeley, CA 94708-3112 , USA
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15
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Précigout PA, Claessen D, Makowski D, Robert C. Does the Latent Period of Leaf Fungal Pathogens Reflect Their Trophic Type? A Meta-Analysis of Biotrophs, Hemibiotrophs, and Necrotrophs. Phytopathology 2020; 110:345-361. [PMID: 31577162 DOI: 10.1094/phyto-04-19-0144-r] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We performed a meta-analysis to search for a relation between the trophic type and latent period of fungal pathogens. The pathogen incubation period and the level of resistance of the hosts were also investigated. This ecological knowledge would help us to more efficiently regulate crop epidemics for different types of pathogens. We gathered latent period data from 103 studies dealing with 51 fungal pathogens of the three major trophic types (25 biotrophs, 15 hemibiotrophs, and 11 necrotrophs), representing 2,542 mean latent periods. We show that these three trophic types display significantly different latent periods. Necrotrophs exhibited the shortest latent periods (<100 degree-days [DD]), biotrophs had intermediate ones (between 100 and 200 DD), and hemibiotrophs had the longest latent periods (>200 DD). We argue that this relation between trophic type and latent period points to two opposing host exploitation strategies: necrotrophs mount a rapid destructive attack on the host tissue, whereas biotrophs and hemibiotrophs avoid or delay the damaging phase. We query the definition of hemibiotrophic pathogens and discuss whether the length of the latent period is determined by the physiological limits inherent to each trophic type or by the adaptation of pathogens of different trophic types to the contrasting conditions experienced in their interaction with the host.
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Affiliation(s)
- Pierre-Antoine Précigout
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS-ENS-INSERM UMR8197, Ecole Normale Supérieure, 75005 Paris, France
- UMR EcoSys, Institut National de la Recherche Agronomique (INRA), AgroParisTech, 78850 Thiverval-Grignon, France
| | - David Claessen
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS-ENS-INSERM UMR8197, Ecole Normale Supérieure, 75005 Paris, France
| | - David Makowski
- UMR Agronomie, INRA, AgroParisTech, Université Paris-Saclay, 78850 Thiverval-Grignon, France
| | - Corinne Robert
- UMR EcoSys, Institut National de la Recherche Agronomique (INRA), AgroParisTech, 78850 Thiverval-Grignon, France
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16
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Parcey M, Gayder S, Castle AJ, Svircev AM. Molecular Profile of Phage Infection: A Novel Approach for the Characterization of Erwinia Phages through qPCR. Int J Mol Sci 2020; 21:E553. [PMID: 31952282 DOI: 10.3390/ijms21020553] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/10/2020] [Accepted: 01/12/2020] [Indexed: 12/14/2022] Open
Abstract
Due to the emergence of antibiotic resistance, phage-mediated biocontrol has become an attractive alternative for pathogen management in agriculture. While the infection characteristics of many phages can be adequately described using plaque assays and optical density, the results from phages of the apple pathogen Erwinia amylovora have low reproducibility with these techniques. Using quantitative real-time PCR (qPCR), the stage of the lytic cycle was determined through a combination of chloroform-based sampling, centrifugation, and DNase treatment. Monitoring the transition of phage genomes through the lytic cycle generates a molecular profile from which phage infection characteristics such as adsorption rate and burst size can be determined. To our knowledge, this is the first report of qPCR being used to determine these infection parameters. The characteristics of four different genera of Erwinia phages were determined. The phage ΦEa461A1 was able to adsorb at a rate up to 6.6 times faster than ΦEa35-70 and ΦEa9-2. The low enrichment titer of ΦEa92 was shown to be due to the absence of lysis. The ΦEa461A1 and ΦEa214 phages had the highest productivity, with burst sizes of 57 virions in 38 min and 185 virions in 98 min, respectively, suggesting these genera would make stronger candidates for the phage-mediated biocontrol of E. amylovora.
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17
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Liu C, Wu X, Niu R, Wu X, Fan R. A new SAIR model on complex networks for analysing the 2019 novel coronavirus (COVID-19). Nonlinear Dyn 2020; 101:1777-1787. [PMID: 32836802 PMCID: PMC7299147 DOI: 10.1007/s11071-020-05704-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 05/17/2020] [Indexed: 05/04/2023]
Abstract
Nowadays, the novel coronavirus (COVID-19) is spreading around the world and has attracted extremely wide public attention. From the beginning of the outbreak to now, there have been many mathematical models proposed to describe the spread of the pandemic, and most of them are established with the assumption that people contact with each other in a homogeneous pattern. However, owing to the difference of individuals in reality, social contact is usually heterogeneous, and the models on homogeneous networks cannot accurately describe the outbreak. Thus, we propose a susceptible-asymptomatic-infected-removed (SAIR) model on social networks to describe the spread of COVID-19 and analyse the outbreak based on the epidemic data of Wuhan from January 24 to March 2. Then, according to the results of the simulations, we discover that the measures that can curb the spread of COVID-19 include increasing the recovery rate and the removed rate, cutting off connections between symptomatically infected individuals and their neighbours, and cutting off connections between hub nodes and their neighbours. The feasible measures proposed in the paper are in fair agreement with the measures that the government took to suppress the outbreak. Furthermore, effective measures should be carried out immediately, otherwise the pandemic would spread more rapidly and last longer. In addition, we use the epidemic data of Wuhan from January 24 to March 2 to analyse the outbreak in the city and explain why the number of the infected rose in the early stage of the outbreak though a total lockdown was implemented. Moreover, besides the above measures, a feasible way to curb the spread of COVID-19 is to reduce the density of social networks, such as restricting mobility and decreasing in-person social contacts. This work provides a series of effective measures, which can facilitate the selection of appropriate approaches for controlling the spread of the COVID-19 pandemic to mitigate its adverse impact on people's livelihood, societies and economies.
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Affiliation(s)
- Congying Liu
- School of Mathematics and Statistics, Wuhan University, Hubei, 430072 China
| | - Xiaoqun Wu
- School of Mathematics and Statistics, Wuhan University, Hubei, 430072 China
- Hubei Key Laboratory of Computational Science, Wuhan University, Hubei, 430072 China
| | - Riuwu Niu
- College of Mathematics and Statistics, Shenzhen University, Shenzhen, 518060 China
| | - Xiuqi Wu
- School of Mathematics and Statistics, Wuhan University, Hubei, 430072 China
| | - Ruguo Fan
- School of Economics and Management, Wuhan University, Hubei, 430072 China
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18
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Welzel L, Schidlitzki A, Twele F, Anjum M, Löscher W. A face-to-face comparison of the intra-amygdala and intrahippocampal kainate mouse models of mesial temporal lobe epilepsy and their utility for testing novel therapies. Epilepsia 2019; 61:157-170. [PMID: 31828786 DOI: 10.1111/epi.16406] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/11/2019] [Accepted: 11/13/2019] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Intracranial (intrahippocampal or intra-amygdala) administration of kainate in rodents leads to spatially restricted brain injury and development of focal epilepsy with characteristics that resemble mesial temporal lobe epilepsy. Such rodent models are used both in the search for more effective antiseizure drugs (ASDs) and in the development of antiepileptogenic strategies. However, it is not clear which of the models is best suited for testing different types of epilepsy therapies. METHODS In the present study, we performed a face-to-face comparison of the intra-amygdala kainate (IAK) and intrahippocampal kainate (IHK) mouse models using the same mouse inbred strain (C57BL/6). For comparison, some experiments were performed in mouse outbred strains. RESULTS Intra-amygdala kainate injection led to more severe status epilepticus and higher mortality than intrahippocampal injection. In male C57BL/6 mice, the latent period to spontaneous recurrent seizures (SRSs) was short or absent in both models, whereas a significantly longer latent period was determined in NMRI and CD-1 outbred mice. When SRSs were recorded from the ipsilateral hippocampus, relatively frequent electroclinical seizures were determined in the IAK model, whereas only infrequent electroclinical seizures but extremely frequent focal electrographic seizures were determined in the IHK model. As a consequence of the differences in SRS frequency, prolonged video-electroencephalographic monitoring and drug administration were needed for testing efficacy of the benchmark ASD carbamazepine in the IAK model, whereas acute drug testing was possible in the IHK model. In both models, carbamazepine was only effective at high doses, indicating ASD resistance to this benchmark drug. SIGNIFICANCE We found a variety of significant differences between the IAK and IHK models, which are important when deciding which of these models is best suited for studies on novel epilepsy therapies. The IAK model appears particularly interesting for studies on disease-modifying treatments, whereas the IHK model is well suited for studying the antiseizure activity of novel ASDs against difficult-to-treated focal seizures.
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Affiliation(s)
- Lisa Welzel
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Alina Schidlitzki
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Friederike Twele
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Muneeb Anjum
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
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19
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Abedon ST. Look Who's Talking: T-Even Phage Lysis Inhibition, the Granddaddy of Virus-Virus Intercellular Communication Research. Viruses 2019; 11:v11100951. [PMID: 31623057 PMCID: PMC6832632 DOI: 10.3390/v11100951] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/15/2019] [Accepted: 09/30/2019] [Indexed: 12/13/2022] Open
Abstract
That communication can occur between virus-infected cells has been appreciated for nearly as long as has virus molecular biology. The original virus communication process specifically was that seen with T-even bacteriophages-phages T2, T4, and T6-resulting in what was labeled as a lysis inhibition. Another proposed virus communication phenomenon, also seen with T-even phages, can be described as a phage-adsorption-induced synchronized lysis-inhibition collapse. Both are mediated by virions that were released from earlier-lysing, phage-infected bacteria. Each may represent ecological responses, in terms of phage lysis timing, to high local densities of phage-infected bacteria, but for lysis inhibition also to locally reduced densities of phage-uninfected bacteria. With lysis inhibition, the outcome is a temporary avoidance of lysis, i.e., a lysis delay, resulting in increased numbers of virions (greater burst size). Synchronized lysis-inhibition collapse, by contrast, is an accelerated lysis which is imposed upon phage-infected bacteria by virions that have been lytically released from other phage-infected bacteria. Here I consider some history of lysis inhibition, its laboratory manifestation, its molecular basis, how it may benefit expressing phages, and its potential ecological role. I discuss as well other, more recently recognized examples of virus-virus intercellular communication.
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Affiliation(s)
- Stephen T Abedon
- Department of Microbiology, The Ohio State University, Mansfield, OH 44906, USA.
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20
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Dzalilova DS, Diatroptova MA, Mkhitarov VA, Diatroptov ME. Infradian Rhythms of Resistance to a Dissociative Anesthetic in Wistar Male Rats under Normal Conditions and After Surgical Removal of the Adrenal Glands and Testes. Bull Exp Biol Med 2019; 166:413-6. [PMID: 30617706 DOI: 10.1007/s10517-019-04362-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Indexed: 10/27/2022]
Abstract
Daily dynamics of changes in the latency of a response to dissociative anesthetic tiletamine (time from injection to ataxia) was studied in mature Wistar rats. Both intramuscular and intravenous administration of the anesthetic was associated with 4-day oscillations of the latent period synchronous with the dynamics of changes in the concentration of glucocorticoid hormones. The period and phases of the infradian rhythm of resistance to the anesthetic remained unchanged after removal of both adrenal glands and testes and administration of corticosterone synthesis blocker trilostane diminishing the 4-day cycle of changes in corticosterone level. Therefore, hormones of the adrenal glands and testes do not play the key role in the mechanisms of formation of the 4-day infradian rhythm.
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21
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Chaudhary DD, Mishra G. Influence of food availability on mate-guarding behaviour of ladybirds. Bull Entomol Res 2018; 108:800-806. [PMID: 29415777 DOI: 10.1017/s0007485318000056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A recent study on ladybird, Menochilus sexmaculatus (Fabricius) demonstrates that males perform post-copulatory mate guarding in the form of prolonged mating durations. We investigated whether food resource fluctuation affects pre- and post-copulatory behaviour of M. sexmaculatus. It has not been studied before in ladybirds. For this, adults were subjected to prey resource fluctuations sequentially at three levels: post-emergence (Poe; 10 days), pre-mating (Prm; 24 h) and post-mating (Pom; 5 days; only female). The food resource conditions at each level could be any one of scarce, optimal or abundant. Pre-copulatory and post-copulatory behaviour, and reproductive output were assessed. Post-emergence and pre-mating nutrient conditions significantly influenced the pre-copulatory behaviour. Males reared on scarce post-emergence conditions were found to require significantly higher number of mating attempts to establish mating unlike males in the other two food conditions. Under scarce post-emergence and pre-mating conditions, time to commencement of mating and latent period were high but opposite result was obtained for mate-guarding duration. Fecundity and per cent egg viability were more influenced by post-mating conditions, with scarce conditions stopping oviposition regardless of pre-mating and post-emergence conditions. Present results indicate that pre- and post-copulatory behaviour of ladybird is plastic in nature in response to food resource fluctuations.
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Affiliation(s)
- D D Chaudhary
- Department of Zoology,Indira Gandhi National Tribal University,Amarkantak,Madhya Pradesh-484887,India
| | - G Mishra
- Department of Zoology,Ladybird Research Laboratory,University of Lucknow,Lucknow,Uttar Pradesh-226007,India
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22
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Bumanglag AV, Sloviter RS. No latency to dentate granule cell epileptogenesis in experimental temporal lobe epilepsy with hippocampal sclerosis. Epilepsia 2018; 59:2019-2034. [PMID: 30338519 DOI: 10.1111/epi.14580] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/19/2018] [Accepted: 09/19/2018] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To determine when spontaneous granule cell epileptiform discharges first occur after hippocampal injury, and to identify the postinjury "latent" period as either a "silent" gestational state of epileptogenesis or a subtle epileptic state in gradual transition to a more obvious epileptic state. METHODS Nonconvulsive status epilepticus evoked by perforant path stimulation in urethane-sedated rats produced selective and extensive hippocampal injury and a "latent" period that preceded the onset of the first clinically obvious epileptic seizures. Continuous granule cell layer depth recording and video monitoring assessed the time course of granule cell hyperexcitability and the onset/offset times of spontaneous epileptiform discharges and behavioral seizures. RESULTS One day postinjury, granule cells in awake rats were hyperexcitable to afferent input, and continuously generated spontaneous population spikes. During the ~2-4 week "latent" period, granule cell epileptiform discharges lasting ~30 seconds caused subtle focal seizures characterized by immobilization and facial automatisms that were undetected by behavioral assessment alone but identified post hoc. Granule cell layer epileptiform discharge duration eventually tripled, which caused the first clinically obvious seizure, ending the "latent" period. Behavioral seizure duration was linked tightly to spontaneous granule cell layer events. Granule cell epileptiform discharges preceded all behavioral seizure onsets, and clonic behaviors ended abruptly within seconds of the termination of each granule cell epileptiform discharge. Noninjurious hippocampal excitation produced no evidence of granule cell hyperexcitability or epileptogenesis. SIGNIFICANCE The latent period in this model is a subtle epileptic state in transition to a more clinically obvious epileptic state, not a seizure-free "gestational" state when an unidentified epileptogenic mechanism gradually develops. Based on the onset/offset times of electrographic and behavioral events, granule cell behavior may be the prime determinant of seizure onset, phenotype, duration, and offset in this model of hippocampal-onset epilepsy. Extensive hippocampal neuron loss could be the primary epileptogenic mechanism.
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Affiliation(s)
| | - Robert S Sloviter
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia.,Department of Neurobiology, Morehouse School of Medicine, Atlanta, Georgia.,Department of Pharmacology & Toxicology, Morehouse School of Medicine, Atlanta, Georgia
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23
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Abstract
Algal viruses are considered to be key players in structuring microbial communities and biogeochemical cycles due to their abundance and diversity within aquatic systems. Their high reproduction rates and short generation times make them extremely successful, often with immediate and strong effects for their hosts and thus in biological and abiotic environments. There are, however, conditions that decrease their reproduction rates and make them unsuccessful with no or little immediate effects. Here, we review the factors that lower viral success and divide them into intrinsic—when they are related to the life cycle traits of the virus—and extrinsic factors—when they are external to the virus and related to their environment. Identifying whether and how algal viruses adapt to disadvantageous conditions will allow us to better understand their role in aquatic systems. We propose important research directions such as experimental evolution or the resurrection of extinct viruses to disentangle the conditions that make them unsuccessful and the effects these have on their surroundings.
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Affiliation(s)
- Elena L Horas
- Community Dynamics Group, Max-Planck for Evolutionary Biology, 24306 Plön, Germany.
- Limnology-Aquatic Ecology and Evolution, Limnological Institute, University of Konstanz, 78464 Konstanz, Germany.
| | - Loukas Theodosiou
- Community Dynamics Group, Max-Planck for Evolutionary Biology, 24306 Plön, Germany.
- Department of Microbial Population Biology, Max-Planck for Evolutionary Biology, 24306 Plön, Germany.
| | - Lutz Becks
- Community Dynamics Group, Max-Planck for Evolutionary Biology, 24306 Plön, Germany.
- Limnology-Aquatic Ecology and Evolution, Limnological Institute, University of Konstanz, 78464 Konstanz, Germany.
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24
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Antonovics J, Abbate JL, Bruns EL, Fields PD, Forrester NJ, Gilbert KJ, Hood ME, Park T, Taylor DR. Effect of the anther-smut fungus Microbotryum on the juvenile growth of its host Silene latifolia. Am J Bot 2018; 105:1088-1095. [PMID: 29995339 DOI: 10.1002/ajb2.1114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 03/21/2018] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Plant pathogens that form persistent systemic infections within plants have the potential to affect multiple plant life history traits, yet we tend to focus only on visible symptoms. Anther smut of Silene latifolia caused by the fungus Microbotryum lychnidis-dioicae induces the anthers of its host to support fungal spore production instead of pollen, and the pathogen is primarily transmitted among flowering plants by pollinators. Nevertheless, most of its life cycle is spent in the asymptomatic vegetative phase, and spores falling on seedlings or nonflowering plants can also infect the host. The purpose of this study was to ask whether the fungus also had an effect on its host plant in the juvenile vegetative phase before flowering as this is important for the disease dynamics in species where infection of seedlings is commonplace. METHODS Leaf length and leaf number of inoculated and uninoculated juvenile plants were compared in greenhouse experiments, and in one experiment, disease status of the plants at flowering was determined. KEY RESULTS Inoculated plants had shorter but more leaves, and reduced root mass at the early juvenile (preflowering) stage. Some of these effects were detectable in plants that were inoculated but showed no disease symptoms at flowering. CONCLUSIONS These results show that pathogenic fungi can have endophyte-like effects even in the total absence of their typical and more charismatic symptoms, and conversely that the assessment of endophyte effects on the fitness of their hosts should include all stages of the host life cycle.
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Affiliation(s)
- Janis Antonovics
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
| | - Jessica L Abbate
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
| | - Emily L Bruns
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
| | - Peter D Fields
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
| | | | | | - Michael E Hood
- Biology Department, Amherst College, Amherst, MA, 01003, USA
| | - Timothy Park
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
| | - Douglas R Taylor
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
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25
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Abstract
Viruses are integral to ecological and evolutionary processes, but we have a poor understanding of what drives variation in key traits across diverse viruses. For lytic viruses, burst size, latent period, and genome size are primary characteristics controlling host-virus dynamics. Here we synthesize data on these traits for 75 strains of phytoplankton viruses, which play an important role in global biogeochemistry. We find that primary traits of the host (genome size, growth rate) explain 40%-50% of variation in burst size and latent period. Specifically, burst size and latent period both exhibit saturating relationships versus the host∶virus genome size ratio, with both traits increasing at low genome size ratios while showing no relationship at high size ratios. In addition, latent period declines as host growth rate increases. We analyze a model of latent period evolution to explore mechanisms that could cause these patterns. The model predicts that burst size may often be set by the host genomic resources available for viral construction, while latent period evolves to permit this maximal burst size, modulated by host metabolic rate. These results suggest that general mechanisms may underlie the evolution of diverse viruses. Future extensions of this work could help explain viral regulation of host populations, viral influence on community structure and diversity, and viral roles in biogeochemical cycles.
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26
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Abstract
The current study aimed to investigate the spatial and temporal patterns of high-frequency oscillations (HFOs) in the intra-/extrahippocampal areas during epileptogenesis. Local field potentials were bilaterally recorded from hippocampus (CA1), thalamus, motor cortex, and prefrontal cortex in 13 rats before and after intrahippocampal kainic acid (KA) lesions. HFOs in the ripple (100-200 Hz) and fast ripple (250-500 Hz) ranges were detected and their rates were computed during different time periods (1-5 weeks) after KA-induced status epilepticus (SE). Recurrent spontaneous seizures were observed in 7 rats after SE, and the other 6 rats did not develop epilepsy. During the latent period, the rate of hippocampal HFOs increased at the ipsilateral site of the KA lesion in both groups, and the HFO rate was significantly higher in the animals that later developed epilepsy. Animals that later developed epilepsy also demonstrated widespread appearance of HFOs, in both the ripple and the fast ripple range, whereas animals that did not develop epilepsy only exhibited changes in the ipsilateral intrahippocampal HFO rate. This study demonstrates an association between an increased rate of widespread HFOs and the later development of epilepsy, suggesting the formation of large-scale distributed pathological networks during epileptogenesis.
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Affiliation(s)
- Lin Li
- Department of Neurology, University of California, Los Angeles, CA, USA
| | - Mayur Patel
- Department of Neurology, University of California, Los Angeles, CA, USA
| | - Joyel Almajano
- Department of Neurology, University of California, Los Angeles, CA, USA
| | - Jerome Engel
- Department of Neurology, University of California, Los Angeles, CA, USA.,Brain Research Institute, University of California, Los Angeles, CA, USA.,Departments of Neurobiology and Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Anatol Bragin
- Department of Neurology, University of California, Los Angeles, CA, USA.,Brain Research Institute, University of California, Los Angeles, CA, USA
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Smith ZZ, Benison AM, Bercum FM, Dudek FE, Barth DS. Progression of convulsive and nonconvulsive seizures during epileptogenesis after pilocarpine-induced status epilepticus. J Neurophysiol 2018; 119:1818-1835. [PMID: 29442558 DOI: 10.1152/jn.00721.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although convulsive seizures occurring during pilocarpine-induced epileptogenesis have received considerable attention, nonconvulsive seizures have not been closely examined, even though they may reflect the earliest signs of epileptogenesis and potentially guide research on antiepileptogenic interventions. The definition of nonconvulsive seizures based on brain electrical activity alone has been controversial. Here we define and quantify electrographic properties of convulsive and nonconvulsive seizures in the context of the acquired epileptogenesis that occurs after pilocarpine-induced status epilepticus (SE). Lithium-pilocarpine was used to induce the prolonged repetitive seizures characteristic of SE; when SE was terminated with paraldehyde, seizures returned during the 2-day period after pilocarpine treatment. A distinct latent period ranging from several days to >2 wk was then measured with continuous, long-term video-EEG. Nonconvulsive seizures dominated the onset of epileptogenesis and consistently preceded the first convulsive seizures but were still present later. Convulsive and nonconvulsive seizures had similar durations. Postictal depression (background suppression of the EEG) lasted for >100 s after both convulsive and nonconvulsive seizures. Principal component analysis was used to quantify the spectral evolution of electrical activity that characterized both types of spontaneous recurrent seizures. These studies demonstrate that spontaneous nonconvulsive seizures have electrographic properties similar to convulsive seizures and confirm that nonconvulsive seizures link the latent period and the onset of convulsive seizures during post-SE epileptogenesis in an animal model. Nonconvulsive seizures may also reflect the earliest signs of epileptogenesis in human acquired epilepsy, when intervention could be most effective. NEW & NOTEWORTHY Nonconvulsive seizures usually represent the first bona fide seizure following a latent period, dominate the early stages of epileptogenesis, and change in severity in a manner consistent with the progressive nature of epileptogenesis. This analysis demonstrates that nonconvulsive and convulsive seizures have different behavioral outcomes but similar electrographic signatures. Alternatively, epileptiform spike-wave discharges fail to recapitulate several key seizure features and represent a category of electrical activity separate from nonconvulsive seizures in this model.
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Affiliation(s)
- Zachariah Z Smith
- Department of Psychology and Neuroscience, University of Colorado , Boulder, Colorado
| | - Alexander M Benison
- Department of Psychology and Neuroscience, University of Colorado , Boulder, Colorado
| | - Florencia M Bercum
- Department of Psychology and Neuroscience, University of Colorado , Boulder, Colorado
| | - F Edward Dudek
- Department of Neurosurgery, University of Utah School of Medicine , Salt Lake City, Utah
| | - Daniel S Barth
- Department of Psychology and Neuroscience, University of Colorado , Boulder, Colorado
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28
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Namli Kalem M, Köşüş A, Kamalak Z, Köşüş N, Kalem Z. Factors affecting the rates of caesarean sections in cases with premature rupture of membranes (PROM) at term. J OBSTET GYNAECOL 2017; 37:585-590. [PMID: 28285555 DOI: 10.1080/01443615.2016.1274291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The aim of this retrospective study was to investigate the factors affecting the rates of caesarean section in cases with premature rupture of membranes (PROM) in term pregnancies. Eighty-two term PROM patients who presented to Turgut Ozal University and Erzurum Nene Hatun Hospitals between 2012 and 2014 were included. The effects of demographics, nulliparity, active-latent phase durations, presence of meconium and chorioamnionitis, requirement of oxytocin and cervical dilation at the initial examination on C/S rates were assessed. The C/S rates were changed with the duration of active period and the duration of latent period. It was found that the presence of cervical dilation at the initial examination significantly reduced the risk for progress to C/S at a rate of 87.5%. C/S rates did not change with other variables. We conclude that the factors increasing the risk for C/S in PROM at term group are not different from the non-term PROM. Impact statement The aim of this retrospective study was to investigate the factors affecting the rates of caesarean section (C/S) in cases with premature rupture of membranes (PROM) in term pregnancies. The C/S rates were changed with the duration of active period and the duration of latent period. It was found that the presence of cervical dilation at the initial examination significantly reduced the risk for progress to C/S at a rate of 87.5%. We conclude that the factors increasing the risk for C/S in PROM at term group, are not different from the non-term PROM groups. Currently, the PROM is considered the start of a pathological process in both term and preterm pregnancies and also considered to increase the rates of caesarean sections. Studies on the management of PROM at term have concentrated rather on whether to intervene for accelerating the labour or spontaneous monitorisation. As found by the studies like this one in the literature, the factors having an impact on C/S rates in the cases of PROM at term are similar to those of non-PROM patients at term, may prevent clinicians from taking an invasive or aggressive approach towards the cases of PROM at term.
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Affiliation(s)
- Muberra Namli Kalem
- a Department of Obstetrics and Gynaecology, School of Medicine , Turgut Ozal University , Ankara , Turkey
| | - Aydın Köşüş
- a Department of Obstetrics and Gynaecology, School of Medicine , Turgut Ozal University , Ankara , Turkey
| | - Zeynep Kamalak
- b Department of Obstetric and Gynecology , Erzurum Nene Hatun Hospital , Erzurum , Turkey
| | - Nermin Köşüş
- a Department of Obstetrics and Gynaecology, School of Medicine , Turgut Ozal University , Ankara , Turkey
| | - Ziya Kalem
- c Gurgan Clinic IVF and Women Health Center , Cankaya/Ankara/Ankara , Turkey
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Abstract
In long-term care facilities (LTCFs), the elderly are apt to be infected because those with latent tuberculosis infections (LTBIs) are at an increased risk for reactivation and post-primary TB disease. We report an outbreak of TB in staff and residents in a LTCF. An outbreak investigation was conducted after two TB cases were reported from the LTCF. A tuberculin skin test (TST), bacteriological examination and chest radiograph were administered to all facility staff and residents. An outbreak is defined as at least two epidemiologically linked cases that have identical Mycobacterium tuberculosis genotype isolates. This outbreak infected eight residents and one staff member, who were confirmed to have TB in a LTCF between September 2011 and October 2012. Based on the Becker method, the latent and infectious periods were estimated at 223·6 and 55·9 days. Two initial TST-negative resident contacts were diagnosed as TB cases through comprehensive TB screening. Observing elderly people who have a negative TST after TB screening appears to be necessary, given the long latent period for controlling a TB outbreak in a LTCF. It is important to consider providing LTBI treatment for elderly contacts.
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Baker A, King D, Marsh J, Makin A, Carr A, Davis C, Kirby C. Understanding the physical and emotional impact of early-stage ADPKD: experiences and perspectives of patients and physicians. Clin Kidney J 2015; 8:531-7. [PMID: 26413277 PMCID: PMC4581379 DOI: 10.1093/ckj/sfv060] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 06/23/2015] [Indexed: 01/04/2023] Open
Abstract
Background Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disorder; however, at the time this research was conducted, no disease-modifying treatment was currently available. Medical texts often describe early-stage disease (Stages 1 and 2) as asymptomatic, but there is evidence from patients of considerable physical and emotional effects. Methods In-depth interviews were conducted with 80 ADPKD patients, 72 nephrologists and 85 primary care physicians (PCPs) from nine European countries to explore the experience and impact of early-stage ADPKD. Interviews were transcribed, translated and analysed centrally using thematic analysis. An additional 600 physicians completed standardised online questionnaires to investigate perceptions of symptom severity and management of early-stage ADPKD. Results Eighty-eight per cent of patients with early-stage disease reported physical symptoms including pain, fatigue, breathlessness, weakness and a general malaise. However, 24% of nephrologists and 16% of PCPs perceived that the patients with early-stage disease did not experience any physical symptoms at all. There was a greater awareness of the emotional impact of disease, but this was still underestimated when compared with patient-reported experiences, which highlighted widespread feelings of loss, uncertainty and fear. Patients and physicians experienced frustration due to the lack of treatment options, especially in the long latent period. For many patients, the inability to affect their disease course whilst living with a diagnosis resulted in feelings of hopelessness, helplessness and depression. Physicians identified a need for improved cooperation between health-care professionals, and increased psychological support for patients. Conclusions Early-stage ADPKD can have a significant physical and emotional impact on patients. Whilst some physicians have an awareness of patient experience during early-stage disease, most underestimate the impact of ADPKD. Both patients and physicians are negatively affected by their inability to alter disease progression.
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Affiliation(s)
- Anna Baker
- London Metropolitan University , London , UK
| | - Dominic King
- Imperial College, University of London , London , UK
| | | | - Andrew Makin
- Otsuka Europe Development and Commercialisation , Buckinghamshire , UK
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31
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Velásquez GE, Aibana O, Ling EJ, Diakite I, Mooring EQ, Murray MB. Time From Infection to Disease and Infectiousness for Ebola Virus Disease, a Systematic Review. Clin Infect Dis 2015; 61:1135-40. [PMID: 26129757 DOI: 10.1093/cid/civ531] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 06/19/2015] [Indexed: 11/13/2022] Open
Abstract
We systematically reviewed the literature to estimate the incubation and latent periods of Ebola virus disease. We found limited epidemiological data from individuals with discrete 1-day exposures. Available data suggest that the incubation and latent periods may differ, and mathematical models may be improved by distinguishing between the two periods.
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Affiliation(s)
- Gustavo E Velásquez
- Divisions of Infectious Diseases Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts
| | - Omowunmi Aibana
- Global Health Equity, Brigham and Women's Hospital Division of Infectious Diseases, Miriam Hospital, Providence, Rhode Island
| | | | - Ibrahim Diakite
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts
| | - Eric Q Mooring
- Department of Epidemiology Center for Communicable Disease Dynamics, Harvard T.H. Chan School of Public Health
| | - Megan B Murray
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts Department of Epidemiology Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts
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32
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Lee JA, Halbert SE, Dawson WO, Robertson CJ, Keesling JE, Singer BH. Asymptomatic spread of huanglongbing and implications for disease control. Proc Natl Acad Sci U S A 2015; 112:7605-10. [PMID: 26034273 PMCID: PMC4475945 DOI: 10.1073/pnas.1508253112] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Huanglongbing (HLB) is a bacterial infection of citrus trees transmitted by the Asian citrus psyllid Diaphorina citri. Mitigation of HLB has focused on spraying of insecticides to reduce the psyllid population and removal of trees when they first show symptoms of the disease. These interventions have been only marginally effective, because symptoms of HLB do not appear on leaves for months to years after initial infection. Limited knowledge about disease spread during the asymptomatic phase is exemplified by the heretofore unknown length of time from initial infection of newly developing cluster of young leaves, called flush, by adult psyllids until the flush become infectious. We present experimental evidence showing that young flush become infectious within 15 d after receiving an inoculum of Candidatus Liberibacter asiaticus (bacteria). Using this critical fact, we specify a microsimulation model of asymptomatic disease spread and intensity in a grove of citrus trees. We apply a range of psyllid introduction scenarios to show that entire groves can become infected with up to 12,000 psyllids per tree in less than 1 y, before most of the trees show any symptoms. We also show that intervention strategies that reduce the psyllid population by 75% during the flushing periods can delay infection of a full grove, and thereby reduce the amount of insecticide used throughout a year. This result implies that psyllid surveillance and control, using a variety of recently available technologies, should be used from the initial detection of invasion and throughout the asymptomatic period.
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Affiliation(s)
- Jo Ann Lee
- Department of Mathematics, University of Florida, Gainesville, FL 32611-8105;
| | - Susan E Halbert
- Division of Plant Industry, Florida Department of Agriculture and Consumer Services, Gainesville, FL 32608-1201
| | - William O Dawson
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850-2243
| | - Cecile J Robertson
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850-2243
| | - James E Keesling
- Department of Mathematics, University of Florida, Gainesville, FL 32611-8105
| | - Burton H Singer
- Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610-0009
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Glassock RJ, Alvarado A, Prosek J, Hebert C, Parikh S, Satoskar A, Nadasdy T, Forman J, Rovin B, Hebert LA. Staphylococcus-related glomerulonephritis and poststreptococcal glomerulonephritis: why defining "post" is important in understanding and treating infection-related glomerulonephritis. Am J Kidney Dis 2015; 65:826-32. [PMID: 25890425 DOI: 10.1053/j.ajkd.2015.01.023] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 01/09/2015] [Indexed: 11/11/2022]
Abstract
A spate of recent publications describes a newly recognized form of glomerulonephritis associated with active staphylococcal infection. The key kidney biopsy findings, glomerular immunoglobulin A (IgA) deposits dominant or codominant with IgG deposits, resemble those of IgA nephritis. Many authors describe this condition as "postinfectious" and have termed it "poststaphylococcal glomerulonephritis." However, viewed through the prism of poststreptococcal glomerulonephritis, the prefix "post" in poststaphylococcal glomerulonephritis is historically incorrect, illogical, and misleading with regard to choosing therapy. There are numerous reports describing the use of high-dose steroids to treat poststaphylococcal glomerulonephritis. The decision to use steroid therapy suggests that the treating physician believed that the dominant problem was a postinfectious glomerulonephritis, not the infection itself. Unfortunately, steroid therapy in staphylococcus-related glomerulonephritis can precipitate severe staphylococcal sepsis and even death and provides no observable benefits. Poststreptococcal glomerulonephritis is an authentic postinfectious glomerulonephritis; poststaphylococcal glomerulonephritis is not. Making this distinction is important from the perspective of history, pathogenesis, and clinical management.
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Affiliation(s)
| | | | - Jason Prosek
- Ohio State University Wexner Medical Center, Columbus, OH
| | | | - Samir Parikh
- Ohio State University Wexner Medical Center, Columbus, OH
| | | | - Tibor Nadasdy
- Ohio State University Wexner Medical Center, Columbus, OH
| | - John Forman
- Renal Division, Brigham and Women's Hospital, Boston, MA
| | - Brad Rovin
- Ohio State University Wexner Medical Center, Columbus, OH
| | - Lee A Hebert
- Ohio State University Wexner Medical Center, Columbus, OH.
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Pariaud B, Berg F, Bosch F, Powers SJ, Kaltz O, Lannou C. Shared influence of pathogen and host genetics on a trade-off between latent period and spore production capacity in the wheat pathogen, Puccinia triticina. Evol Appl 2012; 6:303-12. [PMID: 23467548 PMCID: PMC3586619 DOI: 10.1111/eva.12000] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 07/11/2012] [Indexed: 02/06/2023] Open
Abstract
Crop pathogens are notorious for their rapid adaptation to their host. We still know little about the evolution of their life cycles and whether there might be trade-offs between fitness components, limiting the evolutionary potential of these pathogens. In this study, we explored a trade-off between spore production capacity and latent period in Puccinia triticina, a fungal pathogen causing leaf rust on wheat. Using a simple multivariate (manova) technique, we showed that the covariance between the two traits is under shared control of host and pathogen, with contributions from host genotype (57%), pathogen genotype (18.4%) and genotype × genotype interactions (12.5%). We also found variation in sign and strength of genetic correlations for the pathogen, when measured on different host varieties. Our results suggest that these important pathogen life-history traits do not freely respond to directional selection and that precise evolutionary trajectories are contingent on the genetic identity of the interacting host and pathogen.
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35
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Lloyd A. Sensitivity of Model-Based Epidemiological Parameter Estimation to Model Assumptions. Mathematical and Statistical Estimation Approaches in Epidemiology 2009. [DOI: 10.1007/978-90-481-2313-1_6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Estimation of epidemiological parameters from disease outbreak data often proceeds by fitting a mathematical model to the data set. The resulting parameter estimates are subject to uncertainty that arises from errors (noise) in the data; standard statistical techniques can be used to estimate the magnitude of this uncertainty. The estimates are also dependent on the structure of the model used in the fitting process and so any uncertainty regarding this structure leads to additional uncertainty in the parameter estimates. We argue that if we lack detailed knowledge of the biology of the transmission process, parameter estimation should be accompanied by a structural sensitivity analysis, in addition to the standard statistical uncertainty analysis. Here we focus on the estimation of the basic reproductive number from the initial growth rate of an outbreak as this is a setting in which parameter estimation can be surprisingly sensitive to details of the time course of infection.
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Noe JP. Development of Meloidogyne arenaria on Peanut and Soybean under Two Temperature Cycles. J Nematol 1991; 23:468-476. [PMID: 19283157 PMCID: PMC2619182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Florunner peanut and three soybean cultivars, Centennial, Gasoy 17, and Wright, were inoculated with 48-hour age cohorts of Meloidogyne arenari race 1 second-stage juveniles and placed in a growth chamber set to simulate early season (low temperature) and midseason (high temperature) conditions. Percentages of the initial inoculum penetrating roots 4 and 8 days after inoculation were 2-3 times higher in soybean cultivars than in peanut; 25% on susceptible soybean and 9% on peanut. Penetration and early development of M. arenaria were greater in the higher temperature environment. Penetration percentages were expressed as a function of cumulative degree-days by regression models. Development of M. arenaria 10, 20, and 30 days after inoculation was more rapid on peanut than on soybean. The resistant soybean cultivar Wright had slower development rates than did the other two soybean cultivars. Nematode growth and development were dependent on temperature. In greenhouse experiments, production of eggs by M. arenaria was more than 10 times greater on peanut than on susceptible soybean. The reproductive factor for Wright soybean was less than one, but plant growth parameters indicated that this cultivar was intolerant of M. arenavia.
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37
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Ngwenya BZ, Yamamoto N. Effects of inflammation products on immune systems. Lysophosphatidylcholine stimulates macrophages. Cancer Immunol Immunother 1986; 21:174-82. [PMID: 2938735 PMCID: PMC11038332 DOI: 10.1007/bf00199358] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/1984] [Accepted: 09/02/1985] [Indexed: 01/03/2023]
Abstract
Microbial infection causes inflammation which stimulates macrophage functions. One of the inflammatory products, lysophosphatidylcholine (lyso-Pc), can stimulate macrophage activities. Treatment of mice with lyso-Pc enhanced spreading and ingestion activities of peritoneal macrophages. In vitro treatment of macrophages with lyso-Pc greatly enhanced spreading but not ingestion activities. However, incubation of a mixture of adherent and nonadherent cells with lyso-Pc produced a markedly enhanced ingestion activity of macrophages, implying the contribution of nonadherent cells to the stimulation of macrophages. Time course studies of the stimulation of these macrophages showed that spreading activity is stimulated immediately, even 30 min, after their contact with lyso-Pc while induction of ingestion activity requires a latent period of about 5 h. When the specificity of the macrophage receptors for ingestion was analyzed using defined immunoglobulins (i.e., IgG and IgM) with or without complement, lyso-Pc-activated macrophages efficiently ingested IgG-coated sheep erythrocytes independent of complement. However, macrophages of the same lyso-Pc-treated mice did not ingest erythrocytes coated with IgM and complement. These observations suggest that lyso-Pc-stimulated macrophages ingest the targets via Fc-receptors but not C3b receptors.
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Brodt P, Gordon J. Natural resistance mechanisms may play a role in protection against chemical carcinogenesis. Cancer Immunol Immunother 1982; 13:125-7. [PMID: 6984356 PMCID: PMC11039255 DOI: 10.1007/bf00205312] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/1981] [Accepted: 03/03/1982] [Indexed: 01/22/2023]
Abstract
Mice deprived of B lymphocytes by the chronic administration of anti-IgM antibodies have been shown to possess a heightened natural resistance (NR) to micro-organisms, to parental bone marrow, and to natural killer (NK)-sensitive tumors in vitro and in vivo. Experiments described in this communication indicate that the latent period of primary tumors induced by the injection of methylcholanthrene (MC) is also prolonged in these mice. This observation suggests that NR mechanisms may provide protection against primary chemically induced tumors.
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