126 research outputs found
Anti-inflammatory and antioxidant activities of fractions and compound from Ricinodendron heudelotii (Baill.)
Medicinal plants have been documented over the years to play vital role in promoting human health. The study
evaluated the anti-inflammatory and anti-oxidant activities of different fractions and isolated compound from
Ricinodendron heudelotii leaves. The leaves of Ricinodendron heudelotii were extracted with ethanol and further
partitioned sequentially using petroleum ether, ethylacetate and butanol. Bioassay–guided fractionation of the
ethylacetate fraction was done using repeated column chromatographic technique while the structural elucidation
of pure compound was carried out using mass spectra, 13C and 1H NMR analyses. Antioxidant potential of the
fractions and isolated compound were evaluated with 2,2-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid)
(ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays and anti-inflammatory effect of
fractions was measured by their inhibitory potency on nitric oxide (NO).
Corilagin, an amorphous tannin was isolated and structurally elucidated. Corilagin showed scavenging effect
against ABTS and DPPH radicals which vary in a dose dependent manner. It also showed an antioxidant potential
with IC50 value of 0.003 mg/mL comparable to vitamin C 0.001 mg/mL) used as standard. The butanol and
ethylacetate fractions exhibited significant (p < 0.05) NO inhibition of 60 and 69% respectively after treatment of
RAW 264.7 macrophages with lipopolysaccharide. These results demonstrated the role of isolated corilagin as a
promising potent antioxidant while the ethylacetate and butanol fractions suppressed the expression of an
inflammation mediator by inhibiting nitric oxide
Acute toxicity and antimalarial studies of extract of Allophylus spicatus in animals
Medicinal plants produce a variety of chemical substances with varied physiological effects. They are a huge reservoir of various chemical substances with potential therapeutic properties. Allophylus spicatus is a shrub that belong to the Sapindaceae family. In this study, male albino wistar rats (18) were used for acute toxicity test. Animals were divided into six groups of three rats each. Group A served as the control group while the other groups were dosed orally with 200, 500, 1000, 2000 and 5000 mg/kg body weight of extract and were observed for 14 days. Swiss albino mice (42) were used for the antimalarial study; five groups of six infected mice per group (Groups C–G) were respectively dosed orally with 25 mg chloroquine/kg bw, 200 mg of extract/kg bw, 400 mg/kg bw of extract, 25 mg chl./kg bw + 200 mg/kg bw of extract and 25 mg chl./kg bw + 400 mg/kg bw extract with three groups serving as the control (Groups A–C) for three days. Acute toxicity test and histology analysis on the liver tissue confirmed the safety of the extract at concentrations less than 1000 mg/kg b/w. Antimalarial studies showed the highest activity in the group administered with 400 mg/kg + 25 mg chl./kg b/w. In conclusion, A. spicatus was non-toxic at doses less than 1000 mg/kg and significantly reduced parasitemia count in P. berghei infected mice, thus validating its folkloric usage. © 2021, Korean Society of Toxicology
Increased risk of A(H1N1)pdm09 influenza infection in UK pig industry workers compared to a general population cohort
Background: Pigs are mixing vessels for influenza viral reassortment but the extent of influenza transmission between swine and humans is not well understood.
Objectives: To assess whether occupational exposure to pigs is a risk factor for human infection with human and swine-adapted influenza viruses.
Methods: UK pig industry workers were frequency-matched on age, region, sampling month, and gender with a community-based comparison group from the Flu Watch study. HI assays quantified antibodies for swine and human A(H1) and A(H3) influenza viruses (titres≥40 considered seropositive and indicative of infection). Virus-specific associations between seropositivity and occupational pig exposure were examined using multivariable regression models adjusted for vaccination. Pigs on the same farms were also tested for seropositivity.
Results: 42% of pigs were seropositive to A(H1N1)pdm09. Pig industry workers showed evidence of increased odds of A(H1N1)pdm09 seropositivity compared to the comparison group, albeit with wide confidence intervals (CI), Adjusted Odds Ratio after accounting for possible cross reactivity with other swine A(H1) viruses (aOR) 25.30, 95% CI [1.44-536.34], p=0.028.
Conclusion: The results indicate that A(H1N1)pdm09 virus was common in UK pigs during the pandemic and subsequent period of human A(H1N1)pdm09 circulation, and occupational exposure to pigs was a risk factor for human infection. Influenza immunization of pig industry workers may reduce transmission and the potential for virus reassortment
Increased risk of A(H1N1)pdm09 influenza infection in UK pig industry workers compared to a general population cohort.
BACKGROUND: Pigs are mixing vessels for influenza viral reassortment, but the extent of influenza transmission between swine and humans is not well understood. OBJECTIVES: To assess whether occupational exposure to pigs is a risk factor for human infection with human and swine-adapted influenza viruses. METHODS: UK pig industry workers were frequency-matched on age, region, sampling month, and gender with a community-based comparison group from the Flu Watch study. HI assays quantified antibodies for swine and human A(H1) and A(H3) influenza viruses (titres ≥ 40 considered seropositive and indicative of infection). Virus-specific associations between seropositivity and occupational pig exposure were examined using multivariable regression models adjusted for vaccination. Pigs on the same farms were also tested for seropositivity. RESULTS: Forty-two percent of pigs were seropositive to A(H1N1)pdm09. Pig industry workers showed evidence of increased odds of A(H1N1)pdm09 seropositivity compared to the comparison group, albeit with wide confidence intervals (CIs), adjusted odds ratio after accounting for possible cross-reactivity with other swine A(H1) viruses (aOR) 25·3, 95% CI (1·4-536·3), P = 0·028. CONCLUSION: The results indicate that A(H1N1)pdm09 virus was common in UK pigs during the pandemic and subsequent period of human A(H1N1)pdm09 circulation, and occupational exposure to pigs was a risk factor for human infection. Influenza immunisation of pig industry workers may reduce transmission and the potential for virus reassortment.This work was supported by joint funding from the
Biotechnology and Biological Sciences Research Council
(BBSRC), the Medical Research Council (MRC), and the
Wellcome Trust (WT) [(BBSRC/MRC/WT) BB/H014306/1;
(MRC/WT) MC_U122785833; (MRC) G0800767 and
G0600511]; Alborada Trust (to J.L.N.W.); the RAPIDD
programme of the Science & Technology Directorate (to
J.L.N.W.); US Department of Homeland Security (to
J.L.N.W.); and the Fogarty International Center at the
National Institutes of Health (to J.L.N.W.). DAI is supported
by a fellowship from the National Institute for Health
Research (NIHR) (PDF-2012-05-305) (this research is independent
and the views expressed in this publication are those
of the authors and not necessarily those of the Department of
Health or NIHR).This is the final version of the article. It first appeared from Wiley via https://doi.org//10.1111/irv.12364/abstract
Tracking tracer motion in a 4-D electrical resistivity tomography experiment
A new framework for automatically tracking subsurface tracers in electrical resistivity tomography (ERT) monitoring images is presented. Using computer vision and Bayesian inference techniques, in the form of a Kalman filter, the trajectory of a subsurface tracer is monitored by predicting and updating a state model representing its movements. Observations for the Kalman filter are gathered using the maximally stable volumes algorithm, which is used to dynamically threshold local regions of an ERT image sequence to detect the tracer at each time step. The application of the framework to the results of 2-D and 3-D tracer monitoring experiments show that the proposed method is effective for detecting and tracking tracer plumes in ERT images in the presence of noise, without intermediate manual intervention
Randomized Trial to Compare the Immunogenicity and Safety of a CRM or TT Conjugated Quadrivalent Meningococcal Vaccine in Teenagers who Received a CRM or TT Conjugated Serogroup C Vaccine at Preschool Age
Protection after meningococcal C (MenC) conjugate (MCC) vaccination in early childhood is short-lived. Boosting with a quadrivalent vaccine in teenage years, a high-risk period for MenC disease, should protect against additional serogroups but might compromise MenC response. The carrier protein in the primary MCC vaccine determines the response to MCC booster in toddlers, but the relationship between primary vaccine and booster given later is unclear. This study compared responses to a CRM-conjugated or tetanus toxoid (TT)-conjugated MenACWY vaccine in teenagers primed with different MCC vaccines at preschool age
Randomised trial to compare the immunogenicity and safety of a CRM or TT conjugated quadrivalent meningococcal vaccine in teenagers who received a CRM or TT conjugated serogroup C vaccine at preschool age
Background: Protection after meningococcal C (MenC) conjugate (MCC) vaccination in early childhood is short-lived. Boosting with a quadrivalent vaccine in teenage years, a high-risk period for MenC disease, should protect against additional serogroups but might compromise MenC response. The carrier protein in the primary MCC vaccine determines the response to MCC booster in toddlers, but the relationship between primary vaccine and booster given later is unclear. This study compared responses to a CRM-conjugated or tetanus toxoid (TT)-conjugated MenACWY vaccine in teenagers primed with different MCC vaccines at preschool age.
Methods: Ninety-three teenagers (16–19 years), who were previously randomized at age 3–6 years to receive single-dose MCC–CRM or MCC–TT, were randomized to receive either MenACWY–CRM or MenACWY–TT booster. Serum bactericidal antibodies (SBA, protective titer >=8) were measured before, 1 month and 6 or 9 months after boosting.
Results: Preboosting, MCC–TT-primed teenagers had significantly higher MenC SBA titers than those MCC–CRM-primed (P = 0.02). Postboosting, both MenACWY vaccines induced protective SBA titers to all 4 serogroups in most participants (>=98% at 1 month and >=90% by 9 months postboost). The highest MenC SBA titers were seen in those MCC–TT-primed and MenACWY–TT-boosted [geometric mean titer (GMT) ~ 22,000] followed by those boosted with MenACWY–CRM irrespective of priming (GMT ~ 12,000) and then those MCC–CRM-primed and MenACWY–TT-boosted (GMT ~ 5500). The estimated postbooster MenC SBA decline beyond 1 month was ~40% as time since booster doubles. Both vaccines were well tolerated with no attributable serious adverse events.
Conclusion: Both MenACWY vaccines safely induced protective sustained antibody responses against all targeted serogroups in MCC-primed teenagers
Wastage amidst shortage: Strategies for the mitigation of standby electricity in residential sector in Nigeria
Abstract : Due to rising population and the increasing rate of urbanization, residential electricity usage accounts for a large chunk of Nigeria’s electricity consumption. However, little attention is paid to electricity conservation in the country. In response to this, several studies are been tailored to ensure a rapid reduction in energy consumption through various alternatives including energy efficient technologies given the current state of inadequate electricity supply in the country. On this note, this article discusses the significance of standby electricity in Nigeria. The electricity generation and consumption patterns were briefly discussed while the current electricity saving behaviour and practices among the urban dwellers were detailed with a case study analysed. Based on the case study, it was discovered that the mean standby load across the 30 households were estimated at 60 W ranging from 34-144 W. Also, standby consumption accounts for 13-44% of the annual electricity consumption across the households. Finally, the strategies for electricity saving and sustainable consumption, most especially the mitigation of standby electricity were highlighted
Infection, colonization and shedding of Campylobacter and Salmonella in animals and their contribution to human disease: A review
Livestock meat and offal contribute significantly to human nutrition as sources of high‐quality protein and micronutrients. Livestock products are increasingly in demand, particularly in low‐ and middle‐income settings where economies are growing and meat is increasingly seen as an affordable and desirable food item. Demand is also driving intensification of livestock keeping and processing. An unintended consequence of intensification is increased exposure to zoonotic agents, and a contemporary emerging problem is infection with Campylobacter and Salmonella spp. from livestock (avian and mammalian), which can lead to disease, malabsorption and undernutrition through acute and chronic diarrhoea. This can occur at the farm, in households or through the food chain. Direct infection occurs when handling livestock and through bacteria shed into the environment, on food preparation surfaces or around the house and surroundings. This manuscript critically reviews Campylobacter and Salmonella infections in animals, examines the factors affecting colonization and faecal shedding of bacteria of these two genera as well as risk factors for human acquisition of the infection from infected animals or environment and analyses priority areas for preventive actions with a focus on resource‐poor settings
Identification of membrane-type 1 matrix metalloproteinase tyrosine phosphorylation in association with neuroblastoma progression
<p>Abstract</p> <p>Background</p> <p>Neuroblastoma is a pediatric tumor of neural crest cells that is clinically characterized by its variable evolution, from spontaneous regression to malignancy. Despite many advances in neuroblastoma research, 60% of neuroblastoma, which are essentially metastatic cases, are associated with poor clinical outcome due to the lack of effectiveness of current therapeutic strategies. Membrane-type 1 matrix metalloproteinase (MT1-MMP, MMP-14), an enzyme involved in several steps in tumor progression, has previously been shown to be associated with poor clinical outcome for neuroblastoma. Based on our recent demonstration that MT1-MMP phosphorylation is involved in the growth of fibrosarcoma tumors, we examined the potential role of phosphorylated MT1-MMP in neuroblastoma progression.</p> <p>Methods</p> <p>Tyrosine phosphorylated MT1-MMP was immunostained on tissue microarray samples from 55 patients with neuroblastoma detected by mass screening (known to be predominantly associated with favourable outcome), and from 234 patients with standard diagnosed neuroblastoma. In addition, the effects of a non phosphorylable version of MT1-MMP on neuroblastoma cell migration and proliferation were investigated within three-dimensional collagen matrices.</p> <p>Results</p> <p>Although there is no correlation between the extent of tyrosine phosphorylation of MT1-MMP (pMT1-MMP) and MYCN amplification or clinical stage, we observed greater phosphorylation of pMT1-MMP in standard neuroblastoma, while it is less evident in neuroblastoma from mass screening samples (P = 0.0006) or in neuroblastoma samples from patients younger than one year (P = 0.0002). <it>In vitro </it>experiments showed that overexpression of a non-phosphorylable version of MT1-MMP reduced MT1-MMP-mediated neuroblastoma cell migration and proliferation within a three-dimensional type I collagen matrix, suggesting a role for the phosphorylated enzyme in the invasive properties of neuroblastoma cells.</p> <p>Conclusion</p> <p>Overall, these results suggest that tyrosine phosphorylated MT1-MMP plays an important role in neuroblastoma progression and that its expression is preferentially observed in tumor specimens from neuroblastoma patients showing poor clinical outcome.</p
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