Bacteria/pathogenicity* ; Fungi/pathogenicity* ; Guidelines as Topic ; Humans ; Viruses/pathogenicity*

Heparan sulfate (HS) is ubiquitously expressed on the surfaces and in the extracellular matrix of virtually all cell types, making it an ideal receptor for viral infection. Compared with wild-type viruses, cell culture-adapted laboratory strains exhibit more efficient binding to cellular HS receptors. HS-binding viruses are typically cleared faster from the circulation and cause lower viremia than their non-HS-binding counterparts, suggesting that the HS-binding phenotype is a tissue culture adaptation that lowers virus fitness in vivo. However, when inoculated intracranially, efficient cell attachment through HS binding can contribute to viral neurovirulence. The primary aim of this review is to discuss the roles of HS binding in viral pathogenicity, including peripheral virulence and neurovirulence. Understanding how heparan sulfate functions during virus infection in vivo may prove critical for elucidating the molecular mechanism of viral pathogenesis, and may contribute to the development of therapeutics targeting HS.
Heparitin Sulfate ; physiology ; Humans ; Receptors, Virus ; physiology ; Virulence ; Viruses ; pathogenicity

Six diseases have been found after disease surveys on Notopterygium incisum in Gansu province during 2004 to 2007. They were brown spot (Ascochyta levistici), powdery mildew (Erysiphe heraclei), grey spot (Alternaria sp. ; Alternaria burnsii), leaf spot (Septoria dearnessii), angular leaf spot (Pleospora sp.), leaf streak (Phoma sp.), bacterial angular leaf spot and a virus disease. Bacterial angular leaf spot and powdery mildew are the urgent problems waiting to be solved effectively. All these diseases were reported for the first time in China.
Apiaceae ; microbiology ; virology ; Ascomycota ; isolation & purification ; pathogenicity ; Bacteria ; isolation & purification ; pathogenicity ; China ; Plant Diseases ; microbiology ; virology ; Viruses ; isolation & purification ; pathogenicity

Ubiquitin is highly conserved 76 amino acid protein found in all eukaryotic organisms and ubiquitin-proteasome pathway (UPP) plays a very important role in regulated non-lysosomal ATP dependent protein degradation. This pathway participates in or regulates numerous cellular processes, such as selective protein degradation, cell cycle progression, apoptosis, signal transduction, transcriptional regulation, receptor control by endocytosis, immune response and the processing of antigens. Nevertheless, roles of UPP in virus infection are only beginning to be clarified. Ubiquitin homology has also been found in insect viruses. All viral ubiquitin genes encode an N-terminal ubiquitin sequence and 3-256 amino acids C-terminal peptides. Most of the residues known to be essential for ubiquitin function have been conserved in the viral variant. In Autographa californica nucleopolyhedrovirus (AcMNPV), viral ubiquitin is attached to the inner surface of budded viron membrane by a covalently linked phospholipid and is not essential for viral replication. Currently, insect viruses are the only viruses known to encode ubiquitin. However, ubiquitin also plays a role in the life cycle of other viruses. Host ubiquitin molecules have been found in some plant viruses and other animal viruses. Additionally, Africa swine fever virus (ASFV) encodes a ubiquitin-conjugating enzyme (E2) and a putative causal link between human immunodeficiency virus type 1 (HIV-1) and ubiquitin was established by showing that depletion of the intracellular pool of free ubiquitin inhibits the virus budding. Further analyses indicated that many retroviruses proteins which are required for efficient pinching off the virus bud contain a late domain. The core element of the late domain is a proline-rich motif (PPXY) which mediates the late domain to be ubiquitinated by cellular proteins. Recently, it has been shown that many retroviruses have developed mechanisms to escape the cellular immune response, to facilitate virus replication and to promote virus assembly and budding via host UPP.
African Swine Fever Virus ; metabolism ; pathogenicity ; Animals ; Humans ; Insect Viruses ; metabolism ; pathogenicity ; Proteasome Endopeptidase Complex ; metabolism ; Retroviridae ; metabolism ; pathogenicity ; Ubiquitin ; metabolism ; Ubiquitin-Protein Ligase Complexes ; metabolism ; Virus Diseases ; virology ; Viruses ; pathogenicity

One type of important plant disease resistance, gene-for-gene resistance, is resulted from the interactions between products of the pathogen avirulence (Avr) genes and their matching plant resistance (R) genes. Avr genes have been cloned from a variety of pathogens including fungi, bacteria, viruses and oomycetes. No significant homology is found between sequences of the most cloned Avr genes and those of known proteins or between those of themselves. However, significant homology has been found between sequences of the cloned R genes and those of known proteins or between those of themselves. R proteins consist of similar domains. It has been reported that hypersensitive cell death and resistance, which are induced by interactions between products of different Avr/R gene pairs consisting of similar R genes but different Avr genes, are distinct in development speed, strength, and organ and tissue specificity. Avr genes have dual functions: Pathogens containing Avr genes are avirulent to plants carrying the matching R genes, while they are virulent in race, strain, pathovar or species-specific way to plants without carrying the matching R genes.
Bacteria ; genetics ; pathogenicity ; Fungi ; genetics ; pathogenicity ; Gene Expression ; Genes, Bacterial ; physiology ; Genes, Fungal ; physiology ; Genes, Viral ; physiology ; Plant Diseases ; genetics ; microbiology ; virology ; Plant Viruses ; genetics ; pathogenicity ; Virulence

Humans ; Infectious Disease Transmission, Vertical ; prevention & control ; Kidney Diseases ; prevention & control ; virology ; Viruses ; pathogenicity

Animals ; Cell Transformation, Neoplastic ; Cloning, Molecular ; Hepacivirus ; genetics ; immunology ; pathogenicity ; Hepatitis C Antigens ; toxicity ; Liver Neoplasms, Experimental ; pathology ; virology ; Male ; Oncogenic Viruses ; pathogenicity ; RNA, Messenger ; toxicity ; Rats ; Rats, Sprague-Dawley ; Recombinant Fusion Proteins ; toxicity ; Viral Core Proteins ; toxicity ; Virion ; pathogenicity

Human metapneumovirus (HMPV) shares clinical and epidemiological characteristics with well-known respiratory syncytial virus (RSV). The aim of this study was to investigate the clinical and epidemiological differences between HMPV- and RSV-induced wheezing illnesses. A total of 1,008 nasopharyngeal aspirate specimens was collected from 1,008 pediatric patients hospitalized with acute respiratory tract infection at Inje University Sanggye Paik Hospital from December 2003 to April 2008, and tested for seven common respiratory viruses. Conditions classified as wheezing illness were bronchiolitis, reactive airways disease, and bronchial asthma. HMPV caused a significantly lower proportion of wheezing illness when compared to RSV (48.1% vs. 82.2%, P<0.05). HMPV-induced wheezing illness occurred predominantly in older patients when compared to RSV patients (P<0.001). RSV infections peaked in the fall and winter followed by peaks of HMPV infection in winter and spring. Eosinophil counts were significantly higher (P<0.01) in RSV patients when compared to HMPV patients. These results show that human metapneumovirus patients exhibit several different clinical and epidemiological characteristics, such as higher proportion of wheezing illness, age and seasonal incidence, and eosinophil counts, when compared to RSV patients.
Bronchiolitis/physiopathology/virology ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Korea/epidemiology ; Male ; Metapneumovirus/pathogenicity ; Nasopharynx/virology ; Paramyxoviridae Infections/*epidemiology/*physiopathology/virology ; Respiratory Sounds/*physiopathology ; Respiratory Syncytial Virus Infections/*epidemiology/*physiopathology/virology ; Respiratory Syncytial Viruses/pathogenicity ; Retrospective Studies ; Seasons

Blood Donors ; DNA Virus Infections ; epidemiology ; virology ; Hepatitis Viruses ; classification ; isolation & purification ; pathogenicity ; Hepatitis, Viral, Human ; epidemiology ; virology ; Humans ; Transfusion Reaction

Radix Isatidis (Banlangen in Chinese), used to clearing away heat and toxic material, is a traditional Chinese medicinal (TCM) herb. It is frequently used for preventing and treating infectious diseases caused by viruses. To provide scientific basis for the effect of Radix Isatidis on infectious diseases, the traditional effect and new research development on pharmacological activities are summarized in the review. According to the existed problems in the clinical application, the weak links and shortages of quality research and industrialized production of Radix Isatidis are discussed. It could present the new ideas for improving the technology of Radix Isatidis preparation, and promoting the rational use of the preparation in the clinical treatment.
Animals ; Communicable Disease Control ; methods ; Communicable Diseases ; drug therapy ; virology ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Medicine, Chinese Traditional ; methods ; Viruses ; drug effects ; pathogenicity