Dengue is a vector-borne viral disease, caused by the Flavivirus, Dengue virus (DENV). About 400 million cases and 22000 deaths occur due to dengue throughout the world each year. It is reported in more than 100 countries in the tropics and subtropical regions. A positive-stranded enveloped RNA virus, DENV is principally transmitted by Aedes mosquitoes. It has four antigenically distinct serotypes DENV-1 to 4, with different genotypes, having three structural proteins and seven non-structural proteins. Clinical symptoms of dengue range from mild fever to severe Dengue Haemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS), with thrombocytopenia, leucopenia, and increased vascular permeability. Though primary infection causes activation of immune responses against that DENV serotypes, the severity of the disease in enhanced via heterotypic infection by various serotypes and also by antibody dependent enhancement (ADE). The first licensed DENV vaccine was tetravalent CYD Denvaxia, but it was not approved in all countries. Lack of suitable animal model, proper mechanistic study in pathogenesis and ADE, are the main hindrances in vaccine development. This review summarizes the current knowledge on DENV epidemiology, biology, disease etiology in the context of prevention and protection from dengue virus disease.

Aeromonads have been isolated from varied environmental sources such as polluted and drinking water, as well as from tissues and body fluids of cold and warm-blooded animals. A phenotypically and genotypically heterogenous bacteria, aeromonads can be successfully identified by ribotyping and/or by analysing gyrB gene sequence, apart from classical biochemical characterization. Aeromonads are known to cause scepticemia in aquatic organisms, gastroenteritis and extraintestinal diseases such as scepticemia, skin, eye, wound and respiratory tract infections in humans. Several virulence and antibiotic resistance genes have been identified and isolated from this group, which if present in their mobile genetic elements, may be horizontally transferred to other naive environmental bacteria posing threat to the society. The extensive and indiscriminate use of antibiotics has given rise to many resistant varieties of bacteria. Multidrug resistance genes, such as NDM1, have been identified in this group of bacteria which is of serious health concern. Therefore, it is important to understand how antibiotic resistance develops and spreads in order to undertake preventive measures. It is also necessary to search and map putative virulence genes of Aeromonas for fighting the diseases caused by them. This review encompasses current knowledge of bacteriological, environmental, clinical and virulence aspects of the Aeromonas group and related diseases in humans and other animals of human concern.

There is resurgence of interest in the study of occurrence, genotype and pathogenic associations of human Polyomavirus BK and JC in recent years. In the present study, we have ascertained the presence of BK virus shed in the urine samples of pregnant women and immunocompromised patients, for the first time in Asian Indian population, and have also characterised the prevalent genotypes of the non-coding control regions (NCCRs) of these natural isolates. The results strongly suggest a very high incidence, as well as degree, of BK virus reactivation in this population groups assayed. Approximately 65% of the patients and pregnant women together, tested positive based on polymerase chain reaction (PCR) analysis, and these results were further confirmed by Southern hybridisation and dot blot against BKV specific probes. The NCCRs of the several Indian endemic strains were analysed by sequencing PCR products, amplified directly from urine samples, with oligonucleotide primers designed from the constant region of T-Antigen and VP2 coding sequences. The typical features of the NCCRs of these Indian strains appeared to be comparable and related to the archetypal strain BKV (WW) with some alterations in few key positions. Apart from these subtle alterations, neither any major DNA rearrangement within the NCCR region nor any drastic modification marked BKV strains found in nephropathy and in the healthy subjects (pregnancy). However, in some of the immunocompromised patients studied, the degree of reactivations reflected by viruria, appeared to be much higher compared to other reports.

Background The fronds of Drynaria quercifolia have traditionally been used in rheumatic pain management. The goal of the present study was to validate the potent anti-inflammatory and anti-rheumatoid properties of the methanolic-extract of its rhizome using in vitro, in vivo and in silico strategies. Methods The plant was collected and the methanolic extract was prepared from its rhizome. Protein denaturation test, hypotonicity and heat-induced haemolysis assays were performed in vitro. The in vivo anti-rheumatoid potential was assessed in Freund’s complete adjuvant (FCA)-induced Wistar rat model through inflammatory paw-edema, haematological, biochemical, radiological and histopathological measurements. Moreover, metabolites of methanolic extract were screened by gas chromatography-mass spectrometry (GC-MS) and 3D molecular structures of active components were utilized for in silico docking study using AutoDock. Results In vitro results evinced a significant (p < 0.05) anti-inflammatory activity of the rhizome methanolic extract in a dose-linear response. Further, Drynaria quercifolia rhizome methanolic extract (DME) significantly ameliorated rheumatoid arthritis as indicated by the inhibition of arthritic paw-edema (in millimeter) in the rat rheumatoid arthritis models in both the low (57.71 ± 0.99, p < 0.01) and high dose groups (54.45 ± 1.30, p < 0.001) when compared to arthritic control. Treatment with DME also normalized the haematological (RBC, WBC, platelet counts and hemoglobin contents) and biochemical parameters (total protein, albumin, creatinine and ceruloplasmin) significantly (p < 0.05), which were further supported by histopathological and radiological analyses. Furthermore, GC-MS analysis of DME demonstrated the presence of 47 phytochemical compounds. Compounds like Squalene, Gamma Tocopherol, n-Hexadecanoic acid showed potent inhibition of cyclooxygenase-2 (COX-2), tumor necrosis factor (TNF-α), and interleukin (IL-6) in the docking analysis. Conclusion Results from in vivo and in vitro studies indicated that DME possesses a potent anti-inflammatory and anti-arthritic activity. In silico studies delineated the emergent potent inhibitory effects of several bio-active components on the target inflammatory markers (COX-2, TNF-α and IL-6).

Polyomaviruses (PyVs), belonging to the family Polyomaviridae, are a group of small, nonenveloped, double-stranded, circular DNA viruses widely distributed in the vertebrates. PyVs cause no apparent disease in adult laboratory mice but cause a wide variety of tumors when artificially inoculated into neonates or semipermissive animals. A few human PyVs, such as BK, JC, and Merkel cell PyVs, have been unequivocally linked to pathogenesis under conditions of immunosuppression. Infection is thought to occur early in life and persists for the lifespan of the host. Over evolutionary time scales, it appears that PyVs have slowly co-evolved with specific host animal lineages. Host cell surface glycoproteins and glycolipids seem to play a decisive role in the entry stage of viral infection and in channeling the virions to specific intracellular membrane-bound compartments and ultimately to the nucleus, where the genomes are replicated and packaged for release. Therefore the transport of the infecting virion or viral genome to this site of multiplication is an essential process in productive viral infection as well as in latent infection and transformation. This review summarizes the major findings related to the characterization of the nature of the interactions between PyV and host protein and their impact in host cell invasion.

Background Aloe vera leaf gel has proven efficacious roles in the amelioration of several human diseases and illness-conditions. Specific purified gel-derived bio-constituents as well as the naturally harvested unprocessed A. vera gel have shown promise in modifying systemic inflammation. However, the synergistic role of natural herbal remedies, a mainstay of traditional Indian Ayurveda, has not been evaluated rigorously in this plant. In this study, the prevention of membrane lysis and protein denaturation in the presence of A. vera gel homogenate up to the concentration of 1000 μg/ml of gel has been assessed in vitro. Also, regulation of expression of inflammation-mediator genes (TNF-α and Cox-2) has been investigated in vivo in Freund’s complete adjuvant (FCA)-induced inflammatory arthritic Wistar albino rats in a 28-day long study following the daily oral supplementation of Aloe vera gel homogenate doses up to 0.40 and 0.80 g/kg body weight (low-dose and high-dose groups respectively). Results Our results indicated that A. vera gel homogenate inhibits hypotonicity-induced (74.89 ± 1.26%) and heat-induced (20.86 ± 0.77%) RBC membrane lyses respectively at a concentration of 1000 μg/ml, compared to indomethacin standard (80.52 ± 0.65% and 43.98 ± 1.52% respectively at 200 μg/ml concentration). The similar concentration of gel also showed 39.35 ± 4.25% inhibition of protein denaturation compared to standard diclofenac sodium (46.74 ± 1.84% at 100 μg/ml concentration) in vitro. When assessed in vivo, TNF-α expression was found to be decreased by 35.88% and 38.52%, and Cox-2 expression was found to be decreased by 31.65% and 34.96%, in low-dose and high-dose groups respectively, when compared to the arthritic controls. Conclusions Our findings justify the role of unprocessed A. vera gel homogenate in preventing tissue damage and in the downregulation of TNF-α and Cox-2 gene expressions for the immune-modulation of inflammatory arthritis condition.

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Background There is always an increasing demand for natural remedies from natural sources which can substitute the synthetic therapeutic drugs and lessen their side effects. The present study aims to investigate the antioxidant, anti-inflammatory, antimicrobial properties and in silico docking study of Citrus macroptera leaf (CML) extract in both in vivo and in vitro aspect. Material and methods The antioxidant and anti-inflammatory potential of crude extract was investigated in vitro and in vivo on Wistar albino rat. The antioxidant potentiality also investigated on HepG2 cell line. Antimicrobial activity was evaluated against Staphylococcus sp. and Klebsiella sp. Chemical compounds of the crude extract were identified by GC-MS analysis. In silico docking was also done against NF-ҡB protein. Results At 200 μg/ml concentration, CML significantly scavenges reactive oxygen species (ROS) which was generated on HepG2 cell line. CML showed 71% anti-inflammatory activity (p ≤ 0.001) against carrageenan-induced paw edema in albino Wistar rats. CML extract is very effective against staphylococcus sp. than Klebsiella sp. In the docking analysis, the proximadiol and menthone had − 5.6 kcal/mol and − 5.7 kcal/mol binding affinity with the protein NF-ҡB. Conclusion In the present work, CML provided notable antioxidant, anti-inflammatory, and antimicrobial activity. This activity was confirmed by both in vitro and in vivo followed by in silico docking technique. Overall, the experimental results presented in this study suggest that crude extract of CML could be used as a promising antioxidant and anti-inflammatory candidate with potential benefits.