apparent decrease
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2022 ◽  
Vol 20 (6) ◽  
pp. 5-11
Author(s):  
M. M. Tokarskaya ◽  
E. A. Nayаnova ◽  
O. V. Nechaeva ◽  
S. A. Baranovskaya ◽  
O. M. Afanacyeva ◽  
...  

Relevance. Type-specific immunity does not protect against infection with other pneumococcal serotypes. The phenomenon of the change of serotypes dominating the population of Streptococcus pneumoniae is known, in part due to the intensive recombination process and the phenomenon of «capsule switching». Therefore, the development of a serotype-independent pneumococcal vaccine is an important global public health priority. Ams. Investigation of immunobiological properties of candidate components of a future vaccine with serotype-independent activity. Materials and methods. For immunization of mice, preparations of the capsular polysaccharide of pneumococcus serotype 3 (CPS) were used; protein-containing fraction (PCF) obtained from an aqueous extract of S. pneumoniae 6B cells; recombinant pneumolysin (Ply); mixtures of drugs (CPS + Plу; CPS + PCF; PCF + Plу); conjugate vaccine Prevnar 13 (manufactured by PFIZER Inc. USA). Mice were immunized intraperitoneally, 2 times with an interval of 14 days. Intact mice were used as a control group. To assess the humoral immune IgG response, the method of solid-phase ELISA was used. Phagocytic activity was studied at 7, 14, 21 and 28 days after the second immunization. The cytokine level was determined in the blood sera of mice after the second immunization 2, 4, 8, and 24 hours later on a NovoCyte flow cytometer (ACEA Biosciences, USA) using the MACSPIex CytoKine 10 Kit mouse (Miltenyi Biotec Inc., USA) according to the manufacturer's instructions. Results. Immunization of mice with Ply as well as mixtures with CPS and PCF caused a significant increase in the level of antibodies to Ply. It was found that there was no apparent decrease in the level of antigen-specific antibodies when antigens were administered in combination with others. Pneumolysin, used alone or in combination with PCF and CPS, induces the production of antiinflammatory cytokines IL-4, IL-10, and IL-5 detected throughout the study. This is confirmed by a study of the opsonophagocytic activity of neutrophils from immunized CPS + Ply, Ply + PCF and Ply mice; a significant increase in the number of eosinophils is observed in their blood due to the stimulation of their production of IL-5. Conclusions. As a result of the studies, it was shown that Ply, used alone or in combination with CPS and PCF, has the highest immunogenicity: it stimulates a significant increase in the level of specific antibodies, stimulates Th-2, and induces the production of anti-inflammatory cytokines.


Author(s):  
B. Madhumitha ◽  
N. P. Muralidharan

Background: The study of microorganism is called microbiology, which includes bacteria, viruses, fungi and Protozoa. Microbes play a major role in this field. Microbes are also used for life-saving drugs etc.. The effect of ultraviolet rays on the bacterias are mostly lethal to them, UV is a minor fraction of the solar spectrum reaching the ground surfaces, the UV light radiation will reduce the microbes in the surroundings as well as in the labs. Aim: The aim of this study was to evaluate the effect of the ultraviolet rays on pathogenic bacterias. Materials and methods: Three organisms were selected for the study. Pseudomonas, S. Aureus and Enterococcus. 30 watts Uv tube was used to evaluate the antibacterial activity of the Uv radiation. The exposure time was determined as 5, 10 and 15 mins at a close distance of 10cm. 20 microliter of suspension was taken and mixed in 2 ml of sterile normal saline and exposed for respective duration. Sub culture was done on suitable media after the exposure . Time exposed plates were incubated at 37 degree Celsius overnight and checked for the total CFU and data were tabulated. Results: The Ultraviolet radiation of pathogenic bacteria resulted in a significant reduction of the total colony forming unit. Conclusion: Ultraviolet rays were lethal to the bacterias. There are many  airborne bacterias surrounded by environment ultraviolet rays exposure will cause an apparent decrease in the pathogenic bacterias.


2021 ◽  
Vol 25 (7) ◽  
pp. 1341-1346
Author(s):  
P.O. Osemwenkhae ◽  
P.O. Uadia

Crude lipase (acetone powder) was extracted from freshly sprouted melon seeds (Cucumeropsis manni). The activity, kinetic properties (effect of time, pH, and enzyme and substrate concentration, respectively) as well as the ability of the crude lipase to catalyze the production of methyl esters (biodiesel) were examined. The enzyme activity was determined using n-hexane as the solvent (1:2 v/w solvent: substrate ratio) and the transesterification product was analyzed by HPLC. A linear relationship was observed between reaction time and rate of lipolysis with the optimal activity at 2hr of incubation. Furthermore, the lipase was optimally active at acid pH 5 and lipolysis was achieved optimally when the amount of enzyme was 2.0g. Rate of lipolysis was observed to increase linearly at concentrations up to 5.0g of substrate above which a drop in the rate, with no apparent decrease in activity, was observed. The Km (6.25g) and Vmax (13.33%FFA/hr) were also determined. Analysis of the transesterification product yielded 0.61% alkyl ester, 0.81 %FFA, 93.17% TAG, 4.15% 1, 3-DAG and 1.26% 1, 2-DAG while transesterification efficiency was determined to be at 0.588%. Biodiesel (alkyl esters) prepared with the crude lipase was had a density of 0.872 g/mL while its cloud and pour points were 22°C and 12°C, respectively. The results from this research showed that an active lipase was isolated from sprouted melon seeds. However, the fuel properties of the biodiesel produced did not meet international transportation fuel standards. In order to be used industrially, better reaction conditions need to be established for the lipase.


2021 ◽  
Vol 11 (3) ◽  
pp. 264
Author(s):  
Sghir Cherrouf ◽  
Yassine Salhi ◽  
Amina El Echhab ◽  
Hassan El Grini ◽  
Jihane Tellal ◽  
...  

<p>The tin coating was elaborated electrolytically on an ordinary steel substrate in SnSO<sub>4</sub> based electrolyte in acid medium with additive (bis-glycobenzimidazolone) at ambient temperature. The pH is maintained at 1.2±0.2 Bis-glycobenzimidazolone influence on the electrochemical properties of the tin coating was investigated using stationary polarization, chronopotentiometry, and cyclic voltammetry techniques. These studies show an apparent decrease in cathodic peak current and a drop in potential. The deposition rate also decreases as the concentration of the additive increases.  SEM (Scanning Electron Microscopy) observation and XRD (X-ray Diffraction) analysis showed that the coating consists of good surface quality of the deposit elaborated by the addition of an optimal concentration of bis-glycobenzimidazolone (10<sup>-3</sup>M) in the electrolyte, which constitutes the continuation of a preliminary study.<strong></strong></p>


2021 ◽  
Author(s):  
Daqing Piao ◽  
Morgan L. Denzer ◽  
Gretchen Mafi ◽  
Ranjith Ramanathan

Oxymyoglobin (OxyMb), deoxymyoglobin (DeoxyMb), andmetmyoglobin (MetMb) content on beef longissimus lumborum muscles weredetermined using a near-infrared (NIR) diffuse reflectance spectroscopy (DRS). &nbsp;Approximately eighteen wavelengths spanningfrom 480-650 nm were utilized to develop an algorithm to quantify myoglobinforms. Daily changes in subsurface myoglobin redox states were evaluated forseven days using NIR-DRS and compared with surface color assessed by HunterLab MiniScanspectrophotometer. Both measurements revealed that MetMb increased steadilyover the duration of display, showing a high correlation (R2 = 0.91)between the two methods. Comparatively, while NIR-DRS revealed the OxyMb tohave decreased steadily over the period of display, the HunterLab MiniScanspectrophotometer indicated a much later onset of the apparent decrease ofOxyMb than NIR-DRS reading, resulting in a moderate correlation (R2= 0.64) between the two methods. No correlation was found between the twomethods regarding the changes of DeoxyMb over the duration of display. NIR rayscan penetrate deeper into the muscle sub-surface than visible light and probemyoglobin forms. The newly developed NIR-DRS algorithm has potential as analternative method for the color assessment in post-rigor skeletal muscle.


PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256577
Author(s):  
Michael A. Scaffidi ◽  
Karam Elsolh ◽  
Juana Li ◽  
Yash Verma ◽  
Rishi Bansal ◽  
...  

Background Since 2008, the Canadian Institutes of Health Research (CIHR) has mandated that studies it funds either in whole or in part are required to publish their results as open access (OA) within 12 months of publication using either online repositories and/or OA journals. Yet, there is evidence that authors are poorly compliant with this mandate. Specifically, there has been an apparent decrease in OA publication after 2015, which coincides with a change in the OA policy during the same year. One particular policy change that may have contributed to this decline was lifting the requirement that authors deposit their article in an OA repository immediately upon publication. We investigated the proportion of OA compliance of CIHR-funded studies in the period before and after the policy change of 2015 with manual confirmation of both CIHR funding and OA status. Methods and findings We identified CIHR-funded studies published between the years 2014 to 2017 using a comprehensive search in the Web of Science (WoS). We took a stratified random sample from all four years (i.e. 2014 to 2017), with 250 studies from each year. Two authors independently reviewed the final full-text publications retrieved from the journal web page to determine to confirm CIHR funding, as indicated in the acknowledgements or elsewhere in the paper. For each study, we also collected bibliometric data that included citation count and Altmetric attention score Statistical analyses were conducted using two-tailed Fisher’s exact test with relative risk (RR). Among the 851 receiving CIHR funding published from 2014 to 2017, the percentage of CIHR-funded studies published as OA significantly decreased from 79.6% in 2014 to 70.3% in 2017 (RR = 0.88, 95% CI: 0.79–0.99, P = 0.028). When considering all four years, there was no significant difference in the percentage of CIHR-funded studies published as OA in both 2014 and 2015 compared to both 2016 and 2017 (RR = 0.97, 95% CI: 0.90–1.05, P = 0.493). Additionally, OA publications had significantly higher citation count (both in year of publication and in total) and higher attention scores (P<0.05). Conclusions Overall, we found that there was a significant decrease in the proportion of CIHR funded studies published as OA from 2014 compared to 2017, though this difference did not persist when comparing both 2014–2015 to 2016–2017. The primary limitation was the reliance of self-reported data from authors on CIHR funding status. We posit that this decrease may be attributable to CIHR’s OA policy change in 2015. Further exploration is warranted to both validate these studies using a larger dataset and, if valid, investigate the effects of potential interventions to improve the OA compliance, such as use of a CIHR publication database, and reinstatement of a policy for authors to immediately submit their findings to OA repositories upon publication.


Gut ◽  
2021 ◽  
pp. gutjnl-2020-323392
Author(s):  
Paul Oster ◽  
Laurie Vaillant ◽  
Erika Riva ◽  
Brynn McMillan ◽  
Christina Begka ◽  
...  

ObjectiveIn this study, we determined whether Helicobacter pylori (H. pylori) infection dampens the efficacy of cancer immunotherapies.DesignUsing mouse models, we evaluated whether immune checkpoint inhibitors or vaccine-based immunotherapies are effective in reducing tumour volumes of H. pylori-infected mice. In humans, we evaluated the correlation between H. pylori seropositivity and the efficacy of the programmed cell death protein 1 (PD-1) blockade therapy in patients with non-small-cell lung cancer (NSCLC).ResultsIn mice engrafted with MC38 colon adenocarcinoma or B16-OVA melanoma cells, the tumour volumes of non-infected mice undergoing anticytotoxic T-lymphocyte-associated protein 4 and/or programmed death ligand 1 or anti-cancer vaccine treatments were significantly smaller than those of infected mice. We observed a decreased number and activation status of tumour-specific CD8+ T cells in the tumours of infected mice treated with cancer immunotherapies independent of the gut microbiome composition. Additionally, by performing an in vitro co-culture assay, we observed that dendritic cells of infected mice promote lower tumour-specific CD8+ T cell proliferation. We performed retrospective human clinical studies in two independent cohorts. In the Dijon cohort, H. pylori seropositivity was found to be associated with a decreased NSCLC patient survival on anti-PD-1 therapy. The survival median for H. pylori seropositive patients was 6.7 months compared with 15.4 months for seronegative patients (p=0.001). Additionally, in the Montreal cohort, H. pylori seropositivity was found to be associated with an apparent decrease of NSCLC patient progression-free survival on anti-PD-1 therapy.ConclusionOur study unveils for the first time that the stomach microbiota affects the response to cancer immunotherapies and that H. pylori serology would be a powerful tool to personalize cancer immunotherapy treatment.


Author(s):  
Jan Miller

Background The revised national guidelines for analysis of cerebrospinal fluid for bilirubin in suspected subarachnoid haemorrhage (UK) provide an objective means of assessing cerebrospinal fluid samples to determine the risk of subarachnoid haemorrhage. The guidelines are intended for general use, but samples rendered uninterpretable due to the presence of the antibiotic doxycycline have been described. Here, further cases of antibiotic-based interference, and their implications, are presented. Methods An archival search of cerebrospinal fluid spectra performed at Hallands County Hospital Halmstad was performed for the years 2011 and 2016–2019 in an attempt to locate instances of interference. Each case of suspected interference was further investigated with in vitro reproduction experiments as a means of confirmation and assessment of potential clinical impact. Results A total of 10 cases of cerebrospinal fluid curve interference were discovered: six due to doxycycline, three due to metronidazole and one due to tetracycline. Interference caused by the tetracycline class was revealed through in vitro experimentation to cause an apparent decrease in the sample’s net bilirubin absorbance; the presence of xanthochromia on visual inspection was, however, conserved. Conclusions The problem of cerebrospinal fluid absorbance curve interference might be more common than previously suspected. Due to the potential net bilirubin absorbance-lowering effect of tetracyclines, the author recommends visual examination of cerebrospinal fluid samples in every case.


Author(s):  
Jan Miller

Background The revised national guidelines for analysis of cerebrospinal fluid for bilirubin in suspected subarachnoid haemorrhage (UK) provide an objective means of assessing cerebrospinal fluid (CSF) samples to determine risk of subarachnoid haemorrhage (SAH). The guidelines are intended for general use, but samples rendered uninterpretable due to the presence of the antibiotic doxycycline have been described. Here, further cases of antibiotic- based interference, and their implications, are presented. Methods An archival search of CSF spectra performed at Hallands County Hospital Halmstad was performed for the years 2011 and 2016- 2019 in an attempt to locate instances of interference. Each case of suspected interference was further investigated with in vitro reproduction experiments as a means of confirmation and assessment of potential clinical impact. Results A total of 10 cases of CSF curve interference were discovered: 6 due to doxycycline, 3 due to metronidazole and 1 due to tetracycline. Interference due to the tetracycline class was revealed through in vitro experimentation to cause an apparent decrease in the sample’s net bilirubin absorbance(NBA); the presence of xanthochromia on visual inspection was, however, conserved. Conclusions The problem of CSF absorbance curve interference might be more common than previously suspected. Due to the potential NBA- lowering effect of tetracyclines, the author recommends visual examination of CSF samples in every case.


2021 ◽  
Author(s):  
Alpina Begossi ◽  
Svetlana Salyvonchyk ◽  
Branko Glamuzina ◽  
Alessandro Alves-Pereira ◽  
Carlos Batista ◽  
...  

There are large gaps in our knowledge of the biology of important fish consumed by people in tropical countries, which makes conservation difficult. Small-scale fisheries are difficult to study and regulate, especially in countries with no systematic species monitoring. It is even more difficult to estimate the influence of these fisheries on vulnerable fish species and to diagnose possible damage to local fish populations. In this study, 490 individuals of badejo, or comb grouper (Mycteropeca acutirostris), were observed at the Posto 6 fishery in Copacabana, Rio de Janeiro, for the periods of 2013-2014 and 2018-2020. A pattern of decreasing catches was observed for comb grouper. Therefore, provided that the fishing gear and the number of fish have remained the same, the apparent decrease in comb grouper needs to be further investigated. The results provide information regarding the reproduction of comb grouper, with major spawning season around spring (September-December) and additional spawning during April in SE Brazil. Samples from 96 groupers along the coast of Brazil were obtained, and genetic analyses were conducted. The genetic information obtained for grouper species enabled us to determine the relative genetic proximity of M. acutirostris and Mycteroperca bonaci and to obtain information that can be useful for aquaculture and conservation.


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