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Correlation between viral load and liver cirrhosis in chronic hepatitis B patients

Lili LIU MM , Jiyao WANG MD , Weimin SHE MM ,

《医学前沿(英文)》 2009年 第3卷 第3期   页码 271-276 doi: 10.1007/s11684-009-0054-1

摘要: The aim of this paper is to investigate the relationship between hepatitis B virus (HBV) DNA levels during the course and the progression to cirrhosis with chronic hepatitis B. A total of 239 chronic hepatitis B patients confirmed by liver biopsy between 2001 and 2007 were followed up for a median of 28 months. Compared with the patients without cirrhosis, the patients progressed to cirrhosis were older and with higher HBV-DNA levels at end point. However, there was no significant difference in cirrhosis progression between different HBV-DNA groups at baseline ( = 0.531). Kaplan-Meier analysis showed higher HBV-DNA level at endpoint had increasing risk of cirrhosis ( = 0.019). The results of Cox model indicated that HBV-DNA levels at endpoint, stage of fibrosis, negative hepatitis B e antigen, and γ-glutamyl transpeptidase at baseline were independent risk factors of cirrhosis. The relative risk ratios were 1.898, 1.918, 8.976, and 1.006, respectively. Progression to cirrhosis in chronic hepatitis B patients is correlated with HBV-DNA levels during follow-up.

关键词: hepatitis B     chronic     viral load     liver cirrhosis    

A pilot study on Paxlovid therapy for hemodialysis patients with severe acute respiratory syndrome coronavirus 2 infections

《医学前沿(英文)》 doi: 10.1007/s11684-023-1011-0

摘要: We aimed to investigate the safety and efficacy of nirmatrelvir/ritonavir (Paxlovid) therapy for hemodialysis-dependent patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Thirteen hemodialysis patients infected with the Omicron variant of SARS-CoV-2 from April 3 to May 30, 2022, were recruited. Laboratory parameters and chest CT (computed tomography) imaging were analyzed. The treatment group included six patients who received 150 mg/100 mg of Paxlovid orally once daily for 5 days, whereas the control group included seven patients who received basic treatment. No serious adverse reactions or safety events were recorded. Four control patients progressed to moderate disease, and none in the treatment group showed progression of chest CT findings (P < 0.05). Paxlovid therapy tended toward early viral clearance and low viral load on Day 8. Moreover, 83.3% of the patients in the treatment group and 57.1% of the patients in the control group turned negative within 22 days. In the Paxlovid treatment group, we found significantly increased levels of lymphocytes (P=0.03) and eosinophils (P=0.02) and decreased levels of D-dimer on Day 8 compared with those on Day 1. Paxlovid therapy showed a potential therapeutic effect with good tolerance in hemodialysis patients. The optimal dose and effectiveness evaluation must be further investigated in a largeer cohort.

关键词: Paxlovid     hemodialysis     SARS-CoV-2     viral load     chest CT scan    

Innate immune responses in RNA viral infection

Qian Xu, Yuting Tang, Gang Huang

《医学前沿(英文)》 2021年 第15卷 第3期   页码 333-346 doi: 10.1007/s11684-020-0776-7

摘要: RNA viruses cause a multitude of human diseases, including several pandemic events in the past century. Upon viral invasion, the innate immune system responds rapidly and plays a key role in activating the adaptive immune system. In the innate immune system, the interactions between pathogen-associated molecular patterns and host pattern recognition receptors activate multiple signaling pathways in immune cells and induce the production of pro-inflammatory cytokines and interferons to elicit antiviral responses. Macrophages, dendritic cells, and natural killer cells are the principal innate immune components that exert antiviral activities. In this review, the current understanding of innate immunity contributing to the restriction of RNA viral infections was briefly summarized. Besides the main role of immune cells in combating viral infection, the intercellular transfer of pathogen and host-derived materials and their epigenetic and metabolic interactions associated with innate immunity was discussed. This knowledge provides an enhanced understanding of the innate immune response to RNA viral infections in general and aids in the preparation for the existing and next emerging viral infections.

关键词: innate immune     viral infection     intercellular signaling     metabolic changes     epigenetic changes    

Analysis of antibiotic usage for viral community-acquired pneumonia in adults

Rongmeng Jiang, Bing Han, Chang Dou, Fei Zhou, Bin Cao, Xingwang Li

《医学前沿(英文)》 2021年 第15卷 第1期   页码 139-143 doi: 10.1007/s11684-019-0736-2

摘要: The rationale for the antibiotic treatment of viral community-acquired pneumonia (CAP) in adults was analyzed to develop a clinical reference standard for this condition. Clinical data from 166 patients diagnosed with viral pneumonia across 14 hospitals in Beijing from November 2010 to December 2017 were collected. The indications for medications were evaluated, and the rationale for the use of antibiotics was analyzed. A total of 163 (98.3%) patients with viral pneumonia were treated with antibiotics. A combination of C-reactive protein (CRP) and procalcitonin (PCT) was used as markers to analyze the possible indications for antibiotic use. With threshold levels set at 0.25 µg/L for PCT and 20 mg/L for CRP, the rate of unreasonable use of antibiotics was 55.2%. By contrast, at a CRP level threshold of 60 mg/L, the rate of antibiotic misuse was 77.3%. A total of 39 of the 163 (23.9%) patients did not meet the guidelines for drug selection for viral CAP in adults. The unreasonable use of antibacterial drugs for the treatment of viral CAP in adults is a serious concern. Clinicians must reduce the unnecessary use of antibiotics.

关键词: adult     antibiotic     viral pneumonia    

Transgenic technologies in cassava for nutritional improvement and viral disease resistance: a key strategy

Maliwan NACONSIE,Peng ZHANG

《农业科学与工程前沿(英文)》 2016年 第3卷 第4期   页码 285-294 doi: 10.15302/J-FASE-2016119

摘要: As a major staple food source in Africa and other tropical developing countries, cassava ( ) provides basic sustenance for many subsistence farmers. However, cassava roots mainly accumulate starch with limited contribution of other nutrients such as proteins and vitamins. Also, two viral diseases, cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), cause great losses in cassava production in sub-Saharan Africa and the Indian sub-continent. Genetic engineering provides promising approaches to improve nutritional value and increase resistance to viral diseases in cassava. This report presents several successful case studies on engineering protein content by overexpression of nutritious storage proteins and improving cassava resistance to viral diseases by RNA interference. Perspectives on the sustainable acquisition of new knowledge and development of biotechnology to solve these bottlenecks are discussed.

关键词: Manihot esculenta     protein enhancement     RNA interference     transgenesis     virus resistance    

Development of small-molecule viral inhibitors targeting various stages of the life cycle of emerging

null

《医学前沿(英文)》 2017年 第11卷 第4期   页码 449-461 doi: 10.1007/s11684-017-0589-5

摘要:

In recent years, unexpected outbreaks of infectious diseases caused by emerging and re-emerging viruses have become more frequent, which is possibly due to environmental changes. These outbreaks result in the loss of life and economic hardship. Vaccines and therapeutics should be developed for the prevention and treatment of infectious diseases. In this review, we summarize and discuss the latest progress in the development of small-molecule viral inhibitors against highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus, Ebola virus, and Zika virus. These viruses can interfere with the specific steps of viral life cycle by blocking the binding between virus and host cells, disrupting viral endocytosis, disturbing membrane fusion, and interrupting viral RNA replication and translation, thereby demonstrating potent therapeutic effect against various emerging and re-emerging viruses. We also discuss some general strategies for developing small-molecule viral inhibitors.

关键词: emerging and re-emerging viruses     small-molecule inhibitor     coronavirus     Ebola virus     Zika virus     life cycle    

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

《能源前沿(英文)》 2015年 第9卷 第4期   页码 472-485 doi: 10.1007/s11708-015-0373-7

摘要: It is well recognized that the voltage stability of a power system is affected by the load model and hence, to effectively analyze the reactive power compensation of an isolated hybrid wind-diesel based power system, the loads need to be considered along with the generators in a transient analysis. This paper gives a detailed mathematical modeling to compute the reactive power response with small voltage perturbation for composite load. The composite load is a combination of the static and dynamic load model. To develop this composite load model, the exponential load is used as a static load model and induction motors (IMs) are used as a dynamic load model. To analyze the dynamics of IM load, the fifth, third and first order model of IM are formulated and compared using differential equations solver in Matlab coding. Since the decentralized areas have many small consumers which may consist large numbers of IMs of small rating, it is not realistic to model either a single large rating unit or all small rating IMs together that are placed in the system. In place of using a single large rating IM, a group of motors are considered and then the aggregate model of IM is developed using the law of energy conservation. This aggregate model is used as a dynamic load model. For different simulation studies, especially in the area of voltage stability with reactive power compensation of an isolated hybrid power system, the transfer function of the composite load is required. The transfer function of the composite load is derived in this paper by successive derivation for the exponential model of static load and for the fifth and third order IM dynamic load model using state space model.

关键词: isolated hybrid power system (IHPS)     composite load model     static load     dynamic load     induction motor load model     aggregate load    

A brief review of microRNA and its role in PRRSV infection and replication

Xuekun GUO,Wenhai FENG

《农业科学与工程前沿(英文)》 2014年 第1卷 第2期   页码 114-120 doi: 10.15302/J-FASE-2014022

摘要: Porcine reproductive and respiratory syndrome virus (PRRSV), a single-stranded RNA virus, mainly infects cells of monocyte/macrophage lineage. Recently, host microRNAs were shown to be capable of modulating PRRSV infection and replication by multiple ways such as targeting viral genomic RNA, targeting viral receptor and inducing antiviral response. MicroRNAs are small RNAs and have emerged as important regulators of virus-host cell interactions. In this review, we discuss the identified functions of host microRNAs in relation to PRRSV infection and propose that cellular microRNAs may have a substantial effect on cell or tissue tropism of PRRSV.

关键词: porcine reproductive and respiratory syndrome virus (PRRSV)     microRNA     antiviral     viral tropism    

Genome editing for the treatment of tumorigenic viral infections and virus-related carcinomas

Lan Yu, Xun Tian, Chun Gao, Ping Wu, Liming Wang, Bei Feng, Xiaomin Li, Hui Wang, Ding Ma, Zheng Hu

《医学前沿(英文)》 2018年 第12卷 第5期   页码 497-508 doi: 10.1007/s11684-017-0572-1

摘要:

Viral infections cause at least 10%–15% of all human carcinomas. Over the last century, the elucidation of viral oncogenic roles in many cancer types has provided fundamental knowledge on carcinogenetic mechanisms and established a basis for the early intervention of virus-related cancers. Meanwhile, rapidly evolving genome-editing techniques targeting viral DNA/RNA have emerged as novel therapeutic strategies for treating virus-related carcinogenesis and have begun showing promising results. This review discusses the recent advances of genome-editing tools for treating tumorigenic viruses and their corresponding cancers, the challenges that must be overcome before clinically applying such genome-editing technologies, and more importantly, the potential solutions to these challenges.

关键词: genome-editing tools     tumorigenic virus     delivery method     off-target effect     virus-related carcinoma    

Calculation method of load distribution on pipe threaded connections under tension load

Shoujun CHEN, Lianxin GAO, Qi AN

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 241-248 doi: 10.1007/s11465-011-0219-x

摘要:

This paper presents a new calculation method that can calculate the load distribution on pipe threaded connections under tension load. On the basis of elastic mechanics, the new method was developed by analyzing each thread tooth, and a new deformation and covariant equation by making a mechanics analysis on each thread tooth was obtained. Compared with the traditional method proposed by the previous references, the new deformation and covariant equation could be used to describe the relation between the previous and the next thread tooth. By applying the new method on the sample of P-110S pipe threaded connection, the obtained results show that the load on thread tooth mainly concentrates on the four or five threads engaged and the middle teeth were not utilized well to bear the loads. The model offers a new way to calculate the loads carried on the thread teeth under tension load.

关键词: load distribution     calculation method     pipe threaded connections     tension load    

Comparison of optimal capacitor placement methods in radial distribution system with load growth andZIP load model

Veera Venkata Satya Naryana MURTY, Ashwani KUMAR

《能源前沿(英文)》 2013年 第7卷 第2期   页码 197-213 doi: 10.1007/s11708-013-0249-7

摘要: In this paper, a combined power loss sensitivity (PLS) index-based approach is proposed to determine the optimal location of the capacitors in the radial distribution system (RDS) based on the real and reactive combined loss sensitivity index, as capacitor placement not only reduces real power loss with voltage profile improvement but also reduces reactive power loss due to the reactive power compensation in the network. The results have been obtained with the existing methods of power loss index (PLI) and index vector (IV) method for comparison. Besides, the optimal placement has been obtained with the proposed method as well as existing methods and the total kVar support has been obtained. In addition, the results of net cost savings for the 10-, 34-, and 69-bus systems are obtained for comparison. Moreover, the results have been obtained for a large system of 85 buses to validate the results with combined sensitivity based approach. Furthermore, the load growth factor has been considered in the study which is essential for the planning and expansion of the existing systems, whereas the impact of the realistic load model as ZIP load model has been considered for the study of all the systems.

关键词: load growth     load models     reactive power compensation     radial distribution system     power loss index (PLI)     power loss sensitivity (PLS)     index vector (IV)    

病毒性疾病对奶牛繁殖力的重要影响 Review

D. Claire Wathes, Chike F. Oguejiofor, Carole Thomas, Zhangrui Cheng

《工程(英文)》 2020年 第6卷 第1期   页码 26-33 doi: 10.1016/j.eng.2019.07.020

摘要: 妊娠中期非细胞病变型牛病毒性腹泻病毒(bovine viral diarrhea virus, BVDV)的急性感染会使流产率升高或导致持续感染的犊牛出生。

关键词: 牛病毒性腹泻病毒     牛疱疹病毒1型     牛疱疹病毒4型     施马伦贝格病毒     蓝舌病毒     免疫抑制     胚胎死亡率    

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要: Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词: bridges     multi-lane factor     traffic load     lane load disparity     multi-truck presence     weigh-in-motion data    

Shape design of arch dams under load uncertainties with robust optimization

Fengjie TAN, Tom LAHMER

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 852-862 doi: 10.1007/s11709-019-0522-x

摘要: Due to an increased need in hydro-electricity, water storage, and flood protection, it is assumed that a series of new dams will be build throughout the world. The focus of this paper is on the non-probabilistic-based design of new arch-type dams by applying means of robust design optimization (RDO). This type of optimization takes into account uncertainties in the loads and in the material properties of the structure. As classical procedures of probabilistic-based optimization under uncertainties, such as RDO and reliability-based design optimization (RBDO), are in general computationally expensive and rely on estimates of the system’s response variance, we will not follow a full-probabilistic approach but work with predefined confidence levels. This leads to a bi-level optimization program where the volume of the dam is optimized under the worst combination of the uncertain parameters. As a result, robust and reliable designs are obtained and the result is independent from any assumptions on stochastic properties of the random variables in the model. The optimization of an arch-type dam is realized here by a robust optimization method under load uncertainty, where hydraulic and thermal loads are considered. The load uncertainty is modeled as an ellipsoidal expression. Comparing with any traditional deterministic optimization method, which only concerns the minimum objective value and offers a solution candidate close to limit-states, the RDO method provides a robust solution against uncertainty. To reduce the computational cost, a ranking strategy and an approximation model are further involved to do a preliminary screening. By this means, the robust design can generate an improved arch dam structure that ensures both safety and serviceability during its lifetime.

关键词: arch dam     shape optimization     robust optimization     load uncertainty     approximation model    

The first avian influenza A (H7N9) viral infection in humans in Zhejiang Province, China: a death report

null

《医学前沿(英文)》 2013年 第7卷 第3期   页码 333-344 doi: 10.1007/s11684-013-0275-1

摘要:

This study reports the first death caused by a novel avian influenza A (H7N9) virus in Zhejiang Province, China. The patient had chronic hepatitis B and history of exposure to poultry. The patient initially complained of diarrhea and influenza-like symptoms on March 7 and 14 respectively. The disease progressed to severe pneumonia, sustained hypoxia, and coagulation abnormalities. The patient died on March 27 because of respiratory failure, multiple organ failure, and disseminated intravascular coagulation without oseltamivir treatment. This H7N9 virus from Zhejiang is highly similar to isolates obtained from Shanghai, Jiangsu, Anhui, etc. Analysis of hemagglutinin, neuramidinase, and matrix genes indicated that the isolates share the same avian origin, have low virulence, and are sensitive to oseltamivir, but are resistant to adamantine. Only the isolate that caused the fatality exhibited substitution of Q226I in the HA gene, which indicates a potentially enhanced human affinity. The secondary transmission rate was 1.6% (2/125). Only two health workers presented with influenza-like symptoms, and they subsequently tested negative for H7N9 RNA. In conclusion, underlying disease, late diagnosis, and untimely antiviral treatment are possible high-risk factors for infections and death caused by the low-pathogenicity avian influenza A (H7N9). Person-to-person transmission of the H7N9 virus was not detected among close contacts, but such transmission should be investigated in the future. Expanding and enhancing surveillance will help in the early discovery and diagnosis of suspected cases, which will reduce the number of severe cases and deaths.

关键词: avian influenza A (H7N9) virus     epidemiology     contacts     person-to-person transmission    

标题 作者 时间 类型 操作

Correlation between viral load and liver cirrhosis in chronic hepatitis B patients

Lili LIU MM , Jiyao WANG MD , Weimin SHE MM ,

期刊论文

A pilot study on Paxlovid therapy for hemodialysis patients with severe acute respiratory syndrome coronavirus 2 infections

期刊论文

Innate immune responses in RNA viral infection

Qian Xu, Yuting Tang, Gang Huang

期刊论文

Analysis of antibiotic usage for viral community-acquired pneumonia in adults

Rongmeng Jiang, Bing Han, Chang Dou, Fei Zhou, Bin Cao, Xingwang Li

期刊论文

Transgenic technologies in cassava for nutritional improvement and viral disease resistance: a key strategy

Maliwan NACONSIE,Peng ZHANG

期刊论文

Development of small-molecule viral inhibitors targeting various stages of the life cycle of emerging

null

期刊论文

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

期刊论文

A brief review of microRNA and its role in PRRSV infection and replication

Xuekun GUO,Wenhai FENG

期刊论文

Genome editing for the treatment of tumorigenic viral infections and virus-related carcinomas

Lan Yu, Xun Tian, Chun Gao, Ping Wu, Liming Wang, Bei Feng, Xiaomin Li, Hui Wang, Ding Ma, Zheng Hu

期刊论文

Calculation method of load distribution on pipe threaded connections under tension load

Shoujun CHEN, Lianxin GAO, Qi AN

期刊论文

Comparison of optimal capacitor placement methods in radial distribution system with load growth andZIP load model

Veera Venkata Satya Naryana MURTY, Ashwani KUMAR

期刊论文

病毒性疾病对奶牛繁殖力的重要影响

D. Claire Wathes, Chike F. Oguejiofor, Carole Thomas, Zhangrui Cheng

期刊论文

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

Shape design of arch dams under load uncertainties with robust optimization

Fengjie TAN, Tom LAHMER

期刊论文

The first avian influenza A (H7N9) viral infection in humans in Zhejiang Province, China: a death report

null

期刊论文