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Human platelets are anucleate cells that lack in deoxyribonucleic acid (DNA), thus hampering genomic study on them. However, the presence of their own messenger ribonucleic acid (mRNA) transcript allows functional study via the transcriptome approach. Transcriptome not only allows profiling of platelet but also aids in studying gene regulation in virus infections and other diseases that have an impact on platelets. Some viruses are known to affect the platelet either by causing a reduction or destruction. Dengue virus is one of the most postulated virus having such effect and frequently linked to platelet reduction. The transcriptome approach has a pivotal role in providing a deeper insight to link certain diseases and their effect on platelets. This review critically discusses role of platelet in dengue and other viral diseases of public health relevance, with a specific focus on the methods currently used in platelet transcriptome profiling. [ABSTRACT FROM AUTHOR]

The article talks about response-related gene and signalling pathways identification in spleen of Vibrio parahaemolyticus-infected marine fishes, like the Epinephelus fuscoguttatus (Forskal), with the help of next-generation sequencing. Topics include Vibriosis breaking out in Taiwan, China, identified Vibrio alginolyticus to be the causative pathogen, conducting comparative gene expression analysis on the fishes and identifying differentially expressed genes to be predominating.

The article presents a study of non-immune-related genes and signalling pathways including processing of protein and sugars, as well as drug and steroid metabolism in spleen of Vibrio parahaemolyticus-infected Epinephelus fuscoguttatus (Forskal) marine fish. It suggests that non-immune related pathways provide essential resources and are potentially important as supportive mechanisms in preventing threats from potential pathogens, as ell as potential biomarkers and immunomodulatory agents.

The mechanisms through which brown-marbled grouper accomplishes resistance to infection, particularly against Vibrios, are not yet fully understood. In this study, brown-marbled grouper fingerlings were experimentally infected with Vibrio parahaemolyticus, to identify disease resistance grouper, and the serum proteome profiles were compared between resistant and susceptible candidates, via two-dimensional gel electrophoresis (2- DE). The results showed that putative parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain proteins were among proteins that significantly overexpressed in the resistant fish as compared to the susceptible group of fish, whereas apolipoprotein E and immunoglobulin light chain proteins were observed to be differentially overexpressed in the susceptible fish. Further analysis by peptide sequencing revealed that the immunoglobulin light chain proteins identified in the resistant and susceptible groups differed in amino acid composition. Taken together, the results demonstrated for the first time that putative parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain are among important proteins participating to effect disease resistance mechanism in fish and were overexpressed to function collectively to resist V. parahaemolyticus infection. Most of these molecules are mediators of immune response. [ABSTRACT FROM AUTHOR]

The gram-negative bacterium, Vibrio alginolyticus, has frequently been identified as the pathogen responsible for the infectious disease called vibriosis. This disease is one of the major challenges facing brown-marbled grouper aquaculture, causing fish farmers globally to suffer substantial economic losses. The objective of this study was to investigate the proteins involved in the immune response of brown-marbled grouper fingerlings during their initial encounter with pathogenic organisms. To achieve this objective, a challenge experiment was performed, in which healthy brown-marbled grouper fingerlings were divided into two groups. Fish in the treated group were subjected to intraperitoneal injection with an infectious dose of V. alginolyticus suspended in phosphate-buffered saline ( PBS), and those in the control group were injected with an equal volume of PBS. Blood samples were collected from a replicate number of fish from both groups at 4 h post-challenge and analysed for immune response-related serum proteins via two-dimensional gel electrophoresis. The results showed that 14 protein spots were altered between the treated and control groups; these protein spots were further analysed to determine the identity of each protein via MALDI- TOF/ TOF. Among the altered proteins, three were clearly overexpressed in the treated group compared with the control; these were identified as putative apolipoprotein A-I, natural killer cell enhancement factor and lysozyme g. Based on these results, these three highly expressed proteins participate in immune response-related reactions during the initial exposure (4 h) of brown-marbled grouper fingerling to V. alginolyticus infection. [ABSTRACT FROM AUTHOR]

Introduction: Dengue virus (DENV), the causative agent of dengue disease exists in sylvatic and endemic ecotypes. The cell morphological changes and viral morphogenesis of two dengue ecotypes were examined at the ultrastructural level to identify potential similarities and differences in the surrogate model of enzootic host., Materials and Methods: Vero cells were inoculated with virus at a multiplicity of infection (MOI) of 0.1. Cell cultures were harvested over a time course and processed for transmission electron microscopic imaging., Results: The filopodia protrusions on cell periphery preceded virus entry. Additionally, sylvatic DENV infection was found spreading slower than the endemic DENV. Morphogenesis of both dengue ecotypes was alike but at different level of efficiency in the permissive cells., Conclusions: This is the first ultrastructural study on sylvatic DENV and this comparative study revealed the similarities and differences of cellular responses and morphogenesis of two dengue ecotypes in vitro. The study revealed the weaker infectivity of sylvatic DENV in the surrogate model of enzootic host, which supposed to support better replication of enzootic DENV than endemic DENV.

Enterovirus 5'UTR sequences were detected by RT-PCR in 22 out of 47 suspected hand, foot and mouth disease (HFMD) patients during an outbreak of the disease with incidences of fatal brainstem encephalomyelitis in Malaysia in 1997. Genetic and phylogenetic analyses of the isolates 5'UTR sequences suggest the presence of predominantly enteroviruses with high sequence similarities to Echovirus 1 and Coxsackievirus A9 in the Malaysian peninsula. No fatal cases, however, were associated with these isolates. The remaining isolates, including all (4/4) isolates of the fatal cases from the Malaysian peninsula and Sarawak shared very high sequence identity with enterovirus 71MS (EV71). These findings suggest that several enteroviruses were circulating in Malaysia during the outbreak period, with only EV71 causing fatal infections.

Identification of the aetiologic agent(s) associated with an outbreak of fatal childhood viral infection in Sarawak, Malaysia, in mid 1997 remains elusive. It is reported here that African green monkey kidney (Vero) and human monocytic (U937) cells treated with inocula derived from clinical specimens of some of these fatal cases showed the presence of cellular genomic DNA degradation when the extracted DNA was separated by pulsed field gel electrophoresis (PFGE), oligonucleosomal DNA ladders characteristic of apoptotic cells when the infected cells' DNA was separated by agarose gel electrophoresis, and apoptotic cellular DNA fragmentation when cells were stained using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL). These results suggest that inocula derived from the patients' clinical specimens contain factors which stimulate apoptotic cellular responses in vitro.

Infectious agent(s) causing the fatal Sarawak acute childhood viral infection (SACVI) has not been identified. In the present study, results indicating that inocula prepared from the fatal cases of SACVI induced apoptosis in Vero cell cultures are presented. These findings suggest the possible involvement of apoptotic cellular responses in SACVI.

The present study was undertaken to investigate the antibody responses of dengue fever (DF) patients to specific dengue virus proteins. Partially purified dengue 2 New Guinea C (NGC) strain virus was used as antigen. Under the present experimental protocols, it was observed that almost all DF patients' sera had detectable presence of antibodies which recognize the dengue 2 envelope (E) protein. The convalescent-phase sera especially had significant detectable IgG, IgM and IgE against the protein. In addition, IgGs specific against the NS1 dimer and PrM were also detected. Antibody against the core (C) protein, however, was not detectable in any of the DF patients' sera. The substantial presence of IgG against the PrM in the convalescent-phase sera, and the presence of IgE specific for the E, reflect the potential importance of these antibody responses in the pathogenesis of dengue.