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1.
Nature ; 627(8005): 789-796, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38538940

ABSTRACT

The Antarctic Circumpolar Current (ACC) represents the world's largest ocean-current system and affects global ocean circulation, climate and Antarctic ice-sheet stability1-3. Today, ACC dynamics are controlled by atmospheric forcing, oceanic density gradients and eddy activity4. Whereas palaeoceanographic reconstructions exhibit regional heterogeneity in ACC position and strength over Pleistocene glacial-interglacial cycles5-8, the long-term evolution of the ACC is poorly known. Here we document changes in ACC strength from sediment cores in the Pacific Southern Ocean. We find no linear long-term trend in ACC flow since 5.3 million years ago (Ma), in contrast to global cooling9 and increasing global ice volume10. Instead, we observe a reversal on a million-year timescale, from increasing ACC strength during Pliocene global cooling to a subsequent decrease with further Early Pleistocene cooling. This shift in the ACC regime coincided with a Southern Ocean reconfiguration that altered the sensitivity of the ACC to atmospheric and oceanic forcings11-13. We find ACC strength changes to be closely linked to 400,000-year eccentricity cycles, probably originating from modulation of precessional changes in the South Pacific jet stream linked to tropical Pacific temperature variability14. A persistent link between weaker ACC flow, equatorward-shifted opal deposition and reduced atmospheric CO2 during glacial periods first emerged during the Mid-Pleistocene Transition (MPT). The strongest ACC flow occurred during warmer-than-present intervals of the Plio-Pleistocene, providing evidence of potentially increasing ACC flow with future climate warming.

2.
Indian J Microbiol ; 64(2): 318-327, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39011019

ABSTRACT

In the current scenario of growing world population, limited cultivable land resources, plant diseases, and pandemics are some of the major factors responsible for declining global food security. Along with meeting the food demand, the maintenance of food quality is also required to ensure healthy consumption and marketing. In agricultural fields, pest infestations and bacterial diseases are common causes of crop damage, leading to massive yield losses. Conventionally, antibiotics and several pesticides have been used to manage and control these plant pathogens. However, the overuse of antibiotics and pesticides has led to the emergence of resistant strains of pathogenic bacteria. The bacteriophages are the natural predators of bacteria and are host-specific in their action. Therefore, the use of bacteriophages for the biocontrol of pathogenic bacteria is serving as a sustainable and green solution in crop protection and production. In this review, we have discussed the important plant pathogens and their impact on plant health and yield loss. Further, we have abridged the role of bacteriophages in the protection of crops from bacterial disease by discussing various greenhouse and field trials. Finally, we have discussed the impact of bacteriophages on the plant microbiome, phage resistance, and legal challenges in the registration and commercial production of bacteriophage-based biopesticides. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-024-01204-x.

3.
Emerg Infect Dis ; 27(6): 1745-1748, 2021 06.
Article in English | MEDLINE | ID: mdl-34013856

ABSTRACT

We collected 10 Burkholderia mallei isolates from equids in 9 districts in India during glanders outbreaks in 2013-2016. Multilocus variable-number tandem-repeat analysis showed 7 outbreak area-related genotypes. The study highlights the utility of this analysis for epidemiologically tracing of specific B. mallei isolates during outbreaks.


Subject(s)
Burkholderia mallei , Glanders , Animals , Burkholderia mallei/genetics , Horses , India , Minisatellite Repeats , Molecular Typing
4.
Indian J Clin Biochem ; 34(2): 195-200, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31092993

ABSTRACT

The chronome of lipid peroxidation and anti-oxidant defense mechanisms may relate to the efficacy and management of time qualified preventive therapeutic and dietary interventions. One hundred renal stone patients, 20-60 years of age, and 50 clinically healthy volunteers, 21-45 years, were synchronized for 1 week with diurnal activity from 06:00 to 22:00 and nocturnal rest. All subjects took their usual meals three times daily (breakfast around 08:30, lunch around 13:00, and dinner around 20:30) with usual fluid intake. Drugs known to affect free radical system were not taken. Blood samples were collected at 6-h intervals for 24-h under standardized, presumably 24-h synchronized conditions. Determinations included plasma lipid peroxides, in terms of malondialdehyde (MDA) and blood superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and catalase (CAT) activities. A marked circadian variation was demonstrated for each studied variable by population-mean cosinor in renal stone patients and healthy participants (p < 0.001). By comparison to healthy subjects, parameter tests indicate that the stone formers had a higher MESOR of MDA, but a lower MESOR of SOD, GPx, GR and CAT. Furthermore, the patients also differed from the healthy controls in terms of their circadian amplitude and acrophase (tested jointly) of all variables (p < 0.001). Mapping the broader time structure with multifrequency circadian characteristics of oxidants and anti-oxidants is needed for exploring their role as marker in the treatment and management of urolithiasis.

5.
J Gen Virol ; 97(12): 3458-3466, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27902329

ABSTRACT

The ecosystem is continuously exposed to a wide variety of antimicrobials through waste effluents, agricultural run-offs and animal-related and anthropogenic activities, which contribute to the spread of antibiotic resistance genes (ARGs). The contamination of ecosystems with ARGs may create increased opportunities for their transfer to naive microbes and eventually lead to entry into the human food chain. Transduction is a significant mechanism of horizontal gene transfer in natural environments, which has traditionally been underestimated as compared to transformation. We explored the presence of ARGs in environmental bacteriophages in order to recognize their contribution in the spread of ARGs in environmental settings. Bacteriophages were isolated against environmental bacterial isolates, purified and bulk cultured. They were characterized, and detection of ARG and intI genes including blaTEM, blaOXA-2, intI1, intI2, intI3, tetA and tetW was carried out by PCR. This study revealed the presence of various genes [tetA (12.7 %), intI1 (10.9 %), intI2 (10.9 %), intI3 (9.1 %), tetW (9.1 %) and blaOXA-2 (3.6 %)] and blaTEM in a significantly higher proportion (30.9 %). blaSHV, blaOXA-1, tetO, tetB, tetG, tetM and tetS were not detected in any of the phages. Soil phages were the most versatile in terms of ARG carriage. Also, the relative abundance of tetA differed significantly vis-à-vis source. The phages from organized farms showed varied ARGs as compared to the unorganized sector, although blaTEM ARG incidences did not differ significantly. The study reflects on the role of phages in dissemination of ARGs in environmental reservoirs, which may provide an early warning system for future clinically relevant resistance mechanisms.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/virology , Bacteriophages/genetics , Drug Resistance, Bacterial , Viral Proteins/genetics , Bacteria/genetics , Bacteria/metabolism , Bacteriophages/isolation & purification , Bacteriophages/metabolism , Environmental Microbiology , Gene Transfer, Horizontal , Viral Proteins/metabolism
6.
Bioorg Med Chem Lett ; 26(4): 1237-44, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26803204

ABSTRACT

Cellular calmodulin binds to the SH2 domain of Src kinase, and upon Fas activation it recruits Src into the death-inducing signaling complex. This results in Src-ERK activation of cell survival pathway through which pancreatic cancer cells survive and proliferate. We had proposed that the inhibition of the interaction of calmodulin with Src-SH2 domain is an attractive strategy to inhibit the proliferation of pancreatic cancer. Thus we have performed screening of compound libraries by a combination of methods and identified some compounds (initial leads) that target the calmodulin-binding region on the SH2 domain and inhibit the proliferation of pancreatic cancer cells in in vitro assays. Most of these compounds also exhibited varying degrees of cytotoxicity when tested against immortalized breast epithelial cell line (MCF10A). These initial leads are likely candidates for development in targeted delivery of compounds to cancer cells without affecting normal cells.


Subject(s)
Antineoplastic Agents/chemistry , src-Family Kinases/antagonists & inhibitors , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Calmodulin/chemistry , Calmodulin/metabolism , Calorimetry , Cell Line, Tumor , Cell Survival/drug effects , Humans , Nuclear Magnetic Resonance, Biomolecular , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Protein Binding , src Homology Domains , src-Family Kinases/metabolism
7.
J Basic Microbiol ; 56(4): 432-7, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26748732

ABSTRACT

A bacteriophage (VTCCBPA6) against a pathogenic strain of Aeromonas hydrophila was isolated from the sewage of an organized equine breeding farm. On the basis of TEM analysis, phage belonged to family Myoviridae. PCR amplification and sequence analysis of gp23 gene (encoding for major capsid protein) revealed phylogenetic resemblance to T4 like virus genus. Protein profiling by SDS-PAGE also indicated its resemblance to T4 like phage group. However, the comparison of its gp23 gene sequence with previously reported phages showed similarity with T4-like phages infecting Enterobacteriaceae instead of Aeromonas spp. Thus, to our knowledge, this report points toward the fact that a novel/evolved phage might exist in equine environment against A. hydrophila, which can be potentially used as a biocontrol agent.


Subject(s)
Aeromonas hydrophila/virology , Bacteriophages/isolation & purification , Horse Diseases/microbiology , Aeromonas hydrophila/pathogenicity , Animals , Bacteriophages/classification , Bacteriophages/genetics , Bacteriophages/ultrastructure , Capsid Proteins/genetics , DNA, Viral/genetics , Farms , Genome, Viral , Gram-Negative Bacterial Infections/microbiology , Gram-Negative Bacterial Infections/therapy , Gram-Negative Bacterial Infections/veterinary , Horse Diseases/therapy , Horse Diseases/virology , Horses , Host Specificity , Myoviridae/classification , Myoviridae/isolation & purification , Sewage/microbiology
8.
Indian J Clin Biochem ; 31(2): 215-23, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27069330

ABSTRACT

The circadian rhythm of human circulating lipid components was studied under nearnormal tropical conditions in 162 healthy volunteers (103 males and 59 females; 7 to 75 years of age). They followed a diurnal activity from about 06:00 to about 22:00 and nocturnal rest. These volunteers were divided into four groups: Group A (7-20 years), Group B (21-40 years), Group C (41-60 years) and Group D (61-75 years), comprising 42, 60, 35 and 25 participants, respectively. A marked circadian rhythm was demonstrated for each studied variable in each group by population-mean cosinor analysis (almost invariably p < 0.001). Furthermore, circadian rhythm characteristics were compared among the 4 groups by parameter tests and regressed as a function of age, separately for males and females. A second-order polynomial characterized the MESOR of HDL cholesterol, phospholipids and total lipids, as well as the 24-h amplitude of total cholesterol and phospholipids. The 24-h amplitude of total lipids decreased linearly with age. The 24-h acrophase of the oldest age group (Group D) was advanced in the case of total cholesterol, HDL cholesterol, and total lipids, whereas that of phospholipids was delayed. Mapping the circadian rhythm (an important component of the broader time structure or chronome, which includes a. o., trends with age and extra-circadian components) of lipid components is needed to explore their role in the aging process in health.

9.
ScientificWorldJournal ; 2014: 620906, 2014.
Article in English | MEDLINE | ID: mdl-24523642

ABSTRACT

Thermostabilizing effect of heavy water (D2O) or deuterium oxide has been demonstrated previously on several enzymes and vaccines like oral poliovirus vaccine and influenza virus vaccine. In view of the above observations, effect of heavy water on in situ thermostabilization of recombinant p26 protein on enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of equine infectious anemia virus (EIAV) infection was investigated in the present study. The carbonate-bicarbonate coating buffer was prepared in 60% and 80% D2O for coating the p26 protein in 96-well ELISA plate and thermal stability was examined at 4 °C, 37 °C, 42 °C, and 45 °C over a storage time from 2 weeks to 10 months. A set of positive serum (n = 12) consisting of strong, medium, and weak titer strength (4 samples in each category) and negative serum (n = 30) were assessed in ELISA during the study period. At each time point, ELISA results were compared with fresh plate to assess thermal protective effect of D2O. Gradual increase in the stabilizing effect of 80% D2O at elevated temperature (37 °C < 42 °C < 45 °C) was observed. The 80% D2O provides the thermal protection to rp26 protein in ELISA plate up to 2 months of incubation at 45 °C. The findings of the present study have the future implication of adopting cost effective strategies for generating more heat tolerable ELISA reagents with extended shelf life.


Subject(s)
Deuterium Oxide , Enzyme-Linked Immunosorbent Assay/methods , Equine Infectious Anemia/diagnosis , Infectious Anemia Virus, Equine , Recombinant Proteins , Viral Proteins , Animals , Antibodies, Viral/immunology , Horses , Infectious Anemia Virus, Equine/immunology , Protein Stability , Sensitivity and Specificity , Temperature , Viral Proteins/immunology
10.
ScientificWorldJournal ; 2014: 469407, 2014.
Article in English | MEDLINE | ID: mdl-24672321

ABSTRACT

OBJECTIVE: To express truncated TssB protein of Burkholderia mallei and to evaluate its diagnostic efficacy for serological detection of glanders among equines. MATERIALS AND METHODS: In an attempt to develop recombinant protein based enzyme-linked immunosorbent assay (ELISA), N-terminal 200 amino acid sequences of B. mallei TssB protein-a type 6 secretory effector protein--were expressed in prokaryotic expression system. Diagnostic potential of recombinant TssB protein was evaluated in indirect ELISA using a panel of glanders positive (n = 49), negative (n = 30), and field serum samples (n = 1811). Cross-reactivity of the assay was assessed with equine disease control serum and human melioidosis positive serum. RESULTS: In comparison to CFT, diagnostic sensitivity and specificity of ELISA were 99.7% and 100%, respectively. CONCLUSIONS: The indirect ELISA method using the truncated TssB offered safer and more rapid and efficient means of serodiagnosis of glanders in equines. These data highlight the use of TssB as potential diagnostic antigen for serological diagnosis of glanders.


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Glanders/diagnosis , Horse Diseases/diagnosis , Animals , Base Sequence , Blotting, Western , Burkholderia mallei/genetics , Horses , Molecular Sequence Data , Sequence Homology, Nucleic Acid , Serologic Tests
11.
Arch Virol ; 158(1): 113-22, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23001697

ABSTRACT

The complete genome of the Japanese encephalitis virus (JEV) strain JEV/eq/India/H225/2009(H225), isolated from an infected horse in India, was sequenced and compared to previously published JEV genomes. H225 genome was 10,977-nucleotides long, comprising a single ORF of 10,299-nucleotides, a 5'-UTR of 95 nucleotides and a 3'-UTR of 582 nucleotides. The H225 genome showed high levels of sequence identity with 47 fully sequenced JEV genomes, ranging from 99.3 % to 75.5 % for nucleotides and 99.2 % to 91.5 % for amino acid sequences. Phylogenetic analysis of the full-length sequence indicated that the H225 strain belongs to genotype III and is closely related to the Indian JEV strain Vellore P20778. A comparison of amino acids associated with neurovirulence in the E proteins and non-structural proteins of known virulent and attenuated JEV strains suggested H225 to be a highly virulent strain. This is the first report of whole-genome sequencing of a genotype III JEV genome isolated from equines.


Subject(s)
Encephalitis Virus, Japanese/genetics , Encephalitis Virus, Japanese/isolation & purification , Encephalitis, Japanese/veterinary , Genome, Viral , Horse Diseases/virology , Amino Acid Sequence , Animals , Base Sequence , Encephalitis Virus, Japanese/classification , Encephalitis, Japanese/virology , Horses , India , Molecular Sequence Data , Phylogeny , Viral Proteins/genetics
12.
Chemosphere ; 337: 139318, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37392797

ABSTRACT

A sustainable management of carcinogenic polycyclic aromatic hydrocarbons (PAHs) to synthesize a series of high surface area (SABET of 563-1553 m2 g-1) microporous polymeric adsorbents is reported. The products with high yield (>90%) were obtained within only 30 min at a low temperature of 50 °C using a microwave-assisted approach with 400 W microwave power followed by 30 min of ageing by raising the temperature to 80 °C. The synthesized adsorbents are used for removing another category of carcinogenic pollutants i.e., polycyclic aromatic sulphur heterocycles (PASHs) from model and real fuels. Adsorptive desulphurization experiment in batch mode could reduce the sulphur from high concentrated model (100 ppm) and real (102 ppm) fuels to 8 ppm and 45 ppm respectively. Similarly, desulphurization of model and real fuels with ultralow sulphur concentrations of 10 and 9 ppm, respectively, reduced the final concentration of sulphur to 0.2 and 3 ppm, respectively. Adsorption isotherms, kinetics, and thermodynamic studies have been conducted using batch mode experiments. Adsorptive desulphurization using fixed bed column studies show the breakthrough capacities of 18.6 and 8.2 mgS g-1, for the same high concentrated model and real fuels, respectively. The breakthrough capacities of 1.1 and 0.6 mgS g-1 are estimated for the ultralow sulphur model and real fuels, respectively. The adsorption mechanism, based on the spectroscopic analysis (FTIR and XPS) demonstrates the role of π-π interactions between the adsorbate and adsorbent. The adsorptive desulphurization studies of model and real fuels from batch to fixed bed column mode would offer an in-depth understanding to demonstrate the lab-scale findings for industrial applications. Thus, the present sustainable strategy could manage two classes of carcinogenic petrochemical pollutants, PAHs and PASHs, simultaneously.


Subject(s)
Environmental Pollutants , Polycyclic Aromatic Hydrocarbons , Polycyclic Aromatic Hydrocarbons/analysis , Adsorption , Polymers , Sulfur/analysis , Environmental Pollutants/analysis
13.
Cureus ; 15(11): e48376, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38060711

ABSTRACT

INTRODUCTION: Gestational diabetes mellitus (GDM) is a common complication during pregnancy, with potential adverse effects on maternal and fetal health. Several studies have reported that in diabetic patients, both morphological and functional pathological mechanisms lead to exocrine pancreatic dysfunction. Pancreatic enzyme deficiency or dysfunction result in the inability to digest food properly, giving rise to a range of gastrointestinal (GI) symptoms. We hypothesized that pregnant women with GDM may also have deficiency of pancreatic enzymes, amylase and lipase, leading to persistent GI symptoms beyond the first trimester and impaired quality of life. OBJECTIVE: The objective of this study was to evaluate serum amylase and lipase levels in pregnant women with GDM and association with GI symptoms. Understanding the relationship between GDM and exocrine pancreatic function may help identify novel therapeutic targets and improve the clinical management of GDM women with GI symptoms. MATERIALS AND METHODS: This cross-sectional comparative study included a total of 125 pregnant women in their third trimester, who were either diagnosed with diabetes (n = 25) or were healthy volunteers without diabetes (n = 100). A detailed history, including the presence or absence of GI symptoms and the type of symptoms, was recorded. Serum amylase and lipase levels were measured using enzyme kinetic assay. Data were coded and analysed. RESULTS: GI symptoms were significantly more in GDM women than in normal pregnant women, and GDM women with GI symptoms had significantly lower levels of serum lipase and amylase than normal pregnant women with GI symptoms. CONCLUSION: The study suggests the importance of evaluating serum amylase and lipase in GDM women with GI symptoms, as they may be indicative of underlying pancreatic enzyme deficiency.

14.
Virus Genes ; 45(3): 488-98, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22872567

ABSTRACT

Buffalopox virus (BPXV), a close variant of vaccinia virus (VACV) has emerged as a zoonotic pathogen. The host tropism of poxviruses is governed by host-range genes. Among the host-range genes: E3L, K3L, and C7L are essential for virus replication by preventing interferon resistance, whereas B5R is essential for spread of the virus and evasion from the host's immune response as in VACV. We report sequence analysis of host-range genes: E3L, K3L, C7L, and membrane protein gene (B5R) of BPXVs from buffalo, cattle, and human from recent outbreaks in India-their phylogenetic relationship with reference strain (BP4) and other Orthopoxviruses. BPXVs revealed a sequence homology with VACVs including zoonotic Brazilian VACV-like viruses. The aa sequences of E3L and K3L genes were 100 % similar in buffalo, cattle, and human isolates. However, four significant point mutations (I11K; N12K and S36F in C7L gene and D249G in B5R gene) were observed specific to buffalo isolate only. This signifies that different strains of BPXV were circulated during the outbreak. The mutations in C7L and B5R could play an important role in adaptation of BPXV in human and cattle which needs further functional studies. The strain of BPXV isolated from buffalo may not be adopted in human and cow. Various point mutations were observed in the host-range genes of reference strain (BPXV-BP4) which may be due to several passages of virus in cell culture. The phylogeny constructed based on concatenated gene sequences revealed that BPXVs are not as closely related to vaccine strain (Lister and Lister-derived strain-LC16m8), as hypothesized earlier, rather they are more closely related to reference strain (BPXV-BP4) and other vaccinia and vaccinia-like viruses such as Passatempo and Aracatuba viruses. The availability of information regarding host tropism determinants would allow us to understand molecular mechanism of species tropism of poxviruses which would be useful in unveiling new strategies to control zoonotic poxviral infections.


Subject(s)
Host Specificity , Phylogeny , Vaccinia virus/isolation & purification , Amino Acid Sequence , Amino Acid Substitution , Animals , Buffaloes/virology , Cattle/virology , Chlorocebus aethiops , DNA, Viral/genetics , Disease Outbreaks/veterinary , Genes, Viral , Humans , India , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Point Mutation , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Sequence Analysis, Protein , Sequence Homology, Nucleic Acid , Serial Passage , Vaccinia/veterinary , Vaccinia/virology , Vaccinia virus/genetics , Vaccinia virus/physiology , Vero Cells , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism , Viral Proteins/genetics , Viral Proteins/metabolism , Virus Replication
15.
Sci Total Environ ; 825: 153986, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35189210

ABSTRACT

Coastal lagoons experience removal and leaching of metals due to seasonal fluctuation of salinity coupled with pH and dissolved oxygen variability. Benthic foraminifers are susceptible to seasonal variation in physicochemical conditions. Assessment of bioavailable fraction of selected metals in sediments along the salinity gradient of the largest brackish lagoon in Asia- Chilika was carried out. Further, population density and abnormality index of foraminifera in the sediments were calculated to understand the influence of bioavailable metal on benthic foraminifera. Metal concentrations were higher in the low salinity regions and decreased towards the high salinity regions. This suggests river discharge controls the metal input and distribution in the lagoon. Overall, metal concentrations are high in the residual fraction (F4) followed by interplay within the reducible (F2) or oxidizable (F3) fractions, except for Mn. The seasonal fluctuations of pH and cyclic oxygen deficiency intensified the leaching of Fe, Cr, Cu, Pb, and Zn in the bioavailable fraction in the low salinity region of the lagoon. The presence of metals in bioavailable fractions impacted the normal growth of the abundant Ammonia species. Despite low bioavailable metal concentrations, higher morphological abnormalities were observed in the high salinity regions due to higher energy conditions near the sea. Therefore, abnormalities in the benthic foraminifera are attributed to bioavailability of metals from sediments and natural stress conditions in the coastal lagoon environment.


Subject(s)
Foraminifera , Metals, Heavy , Water Pollutants, Chemical , Biological Availability , Environmental Monitoring , Geologic Sediments , Metals, Heavy/analysis , Rivers , Water Pollutants, Chemical/analysis
16.
Vaccines (Basel) ; 9(12)2021 Dec 02.
Article in English | MEDLINE | ID: mdl-34960169

ABSTRACT

Vaccination of cattle and buffaloes with Brucella abortus strain 19 has been the mainstay for control of bovine brucellosis. However, vaccination with S19 suffers major drawbacks in terms of its safety and interference with serodiagnosis of clinical infection. Brucella abortus S19∆per, a perosamine synthetase wbkB gene deletion mutant, overcomes the drawbacks of the S19 vaccine strain. The present study aimed to evaluate the potential of Brucella abortus S19Δper vaccine candidate in the natural host, buffaloes. Safety of S19∆per, for animals use, was assessed in guinea pigs. Protective efficacy of vaccine was assessed in buffaloes by immunizing with normal dose (4 × 1010 colony forming units (CFU)/animal) and reduced dose (2 × 109 CFU/animal) of S19Δper and challenged with virulent strain of B. abortus S544 on 300 days post immunization. Bacterial persistency of S19∆per was assessed in buffalo calves after 42 days of inoculation. Different serological, biochemical and pathological studies were performed to evaluate the S19∆per vaccine. The S19Δper immunized animals showed significantly low levels of anti-lipopolysaccharides (LPS) antibodies. All the immunized animals were protected against challenge infection with B. abortus S544. Sera from the majority of S19Δper immunized buffalo calves showed moderate to weak agglutination to RBPT antigen and thereby, could apparently be differentiated from S19 vaccinated and clinically-infected animals. The S19Δper was more sensitive to buffalo serum complement mediated lysis than its parent strain, S19. Animals culled at 6-weeks-post vaccination showed no gross lesions in organs and there was comparatively lower burden of infection in the lymph nodes of S19Δper immunized animals. With attributes of higher safety, strong protective efficacy and potential of differentiating infected from vaccinated animals (DIVA), S19Δper would be a prospective alternate to conventional S19 vaccines for control of bovine brucellosis as proven in buffaloes.

17.
Virus Evol ; 7(1): veab009, 2021 Jan.
Article in English | MEDLINE | ID: mdl-35186323

ABSTRACT

Foot-and-mouth disease (FMD) is a highly contagious animal disease caused by an RNA virus subdivided into seven serotypes that are unevenly distributed in Asia, Africa, and South America. Despite the challenges of controlling FMD, since 1996 there have been only two outbreaks attributed to serotype C, in Brazil and in Kenya, in 2004. This article describes the historical distribution and origins of serotype C and its disappearance. The serotype was first described in Europe in the 1920s, where it mainly affected pigs and cattle but as a less common cause of outbreaks than serotypes O and A. No serotype C outbreaks have been reported in Europe since vaccination stopped in 1990. FMD virus is presumed to have been introduced into South America from Europe in the nineteenth century, although whether serotype C evolved there or in Europe is not known. As in Europe, this serotype was less widely distributed and caused fewer outbreaks than serotypes O and A. Since 1994, serotype C had not been reported from South America until four small outbreaks were detected in the Amazon region in 2004. Elsewhere, serotype C was introduced to Asia, in the 1950s to the 1970s, persisting and evolving for several decades in the Indian subcontinent and for eighteen years in the Philippines. Serotype C virus also circulated in East Africa between 1957 and 2004. Many serotype C viruses from European and Kenyan outbreaks were closely related to vaccine strains, including the most recently recovered Kenyan isolate from 2004. International surveillance has not confirmed any serotype C cases, worldwide, for over 15 years, despite more than 2,000 clinical submissions per year to reference laboratories. Serology provides limited evidence for absence of this serotype, as unequivocal interpretation is hampered by incomplete intra-serotype specificity of immunoassays and the continued use of this serotype in vaccines. It is recommended to continue strengthening surveillance in regions of FMD endemicity, to stop vaccination against serotype C and to reduce working with the virus in laboratories, since inadvertent escape of virus during such activities is now the biggest risk for its reappearance in the field.

18.
Arch Virol ; 155(1): 89-95, 2010.
Article in English | MEDLINE | ID: mdl-19936612

ABSTRACT

Sequence analysis of segment 2 (seg-2) of three Indian bluetongue virus (BTV) isolates, Dehradun, Rahuri and Bangalore revealed 99% nucleotide identity amongst them and 96% with the reference BTV 23. Phylogenetic analysis grouped the isolates in 'nucleotype D'. The deduced amino acid (aa) sequence of the Bangalore isolate showed a high variability in a few places compared to other isolates. B-cell epitope analyses predicted an epitope that is present exclusively in the Bangalore isolate. Two-way cross serum neutralization confirmed that Bangalore isolate is antigenically different from the other two isolates. The results of this study suggest that these three isolates are VP2 variants of BTV 23. This signifies that non-cross-neutralizing variants of the same BTV serotype should be included in vaccine preparation.


Subject(s)
Bluetongue virus/classification , Bluetongue virus/isolation & purification , Bluetongue/virology , Capsid Proteins/genetics , Animals , Bluetongue/immunology , Bluetongue virus/genetics , Bluetongue virus/immunology , Capsid Proteins/immunology , Molecular Sequence Data , Neutralization Tests , Phylogeny , RNA, Viral/genetics , Sheep
20.
Int J Oncol ; 32(4): 797-807, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18360707

ABSTRACT

Glycosylation of proteins plays multiple roles in cell-cell and cell-matrix interactions. Fucose is a monosaccharide associated with glycosylation events and is known to be over-expressed in many malignant tumors. By using alpha-L-fucosidase (alpha-L-fase), a glycosidase that specifically removes alpha-L-fucose (alpha-L-f), we have examined the potential effects of defucosylation on tumor functions, focusing on tumor progression in the context of the interaction of tumor cells with the extracellular microenvironment. In this submission, we report that alpha-L-fase treatment decreases, in static assays, tumor cell adhesion to a wide variety of ECM components including fibronectin, laminin, collagen I, hyaluronic acid and the complex human biomatrix, HuBiogel(R). By immunofluorescence, co-localization of beta1 integrin and alpha-L-f was found to decrease accordingly. Sialyl Lewis X, an alpha-L-f-containing tetrasaccharide, which modulates the rolling of leukocytes and tumor cells on endothelium, was found to be diminished on human breast cancer cells after alpha-L-fase treatment. Using a dynamic flow chamber system, we were able to determine that defucosylation impaired the rolling of mammary cancer cells on human umbilical vein endothelial cells while significantly increasing their flow speed. Further, the rolling capability of these defucosylated tumor cells was also impaired on purified E and P-selectin matrices. Based on these data, we hypothesize that decreased fucosylation impairs the interaction between tumor cells and their external milieu, which in turn, affects key cell functions modulating tumor progression. Building on our previous studies which demonstrated alpha-L-fase decreased tumor cell invasion while significantly reducing MMP-9 activity, when added to the fact that decreased adhesion on HUVEC occurs in the presence of alpha-L-fase also leads us to propose that defucosylation may modulate metastasis, and thus provides a promising additional glycobiotic target for novel therapies.


Subject(s)
Breast Neoplasms/pathology , Fucose/physiology , Glycoproteins/physiology , Cell Adhesion , Cell Line, Tumor , Cell Movement , E-Selectin/analysis , Endothelial Cells/physiology , Female , Humans , Intercellular Adhesion Molecule-1/analysis , Oligosaccharides/blood , P-Selectin/analysis , Sialyl Lewis X Antigen , alpha-L-Fucosidase/pharmacology
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