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1.
Microbiol Immunol ; 68(4): 155-159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311883

RESUMO

Streptococcus pneumoniae is a causative agent of community-acquired pneumonia. Upon pneumococcal infection, innate immune cells recognize pneumococcal lipoproteins via Toll-like receptor 2 and induce inflammation. Here, we generated a strain of S. pneumoniae deficient in lipoprotein signal peptidase (LspA), a transmembrane type II signal peptidase required for lipoprotein maturation, to investigate the host immune response against this strain. Triton X-114 phase separation revealed that lipoprotein expression was lower in the LspA-deficient strain than in the wild-type strain. Additionally, the LspA-deficient strain decreased nuclear factor-κB activation and cytokine production in THP-1 cells, indicating impaired innate immune response against the strain.


Assuntos
Ácido Aspártico Endopeptidases , Streptococcus pneumoniae , Receptor 2 Toll-Like , Animais , Camundongos , Streptococcus pneumoniae/genética , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Proteínas de Bactérias/metabolismo , Lipoproteínas/genética , Lipoproteínas/metabolismo , Camundongos Endogâmicos C57BL
2.
Antibiotics (Basel) ; 13(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275335

RESUMO

This study aimed to investigate the effects of dental coating materials on Streptococcus mutans biofilm formation. The test materials were PRG Barrier Coat (PRG), BioCoat Ca (BioC), and FluorDental Jelly (FluorJ). Bovine enamel specimens were demineralized to mimic early enamel lesions. The biofilm was developed on a specimen treated with one of the materials by using a modified Robbins device flow-cell system. Scanning electron and fluorescence confocal laser scanning microscopy, viable and total cell counts, and gene expression assessments of the antibiofilm were performed. Ion incorporation was analyzed using a wavelength-dispersive X-ray spectroscopy electron probe microanalyzer. All materials allowed biofilm formation but reduced its volume. FluorJ was the only material that inhibited biofilm accumulation and had a bactericidal effect, revealing 0.66 log CFU in viable cells and 1.23 log copy reduction in total cells compared with the untreated group after 24 h of incubation. The ions released from PRG varied depending on the element. BioC contributed to enamel remineralization by supplying calcium ions while blocking the acid produced from the biofilm. In summary, the dental coating materials physically prevented acid attacks from the biofilm while providing ions to the enamel to improve its mechanical properties.

3.
Sci Adv ; 9(10): eadd8125, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36897952

RESUMO

While most research has focused on the legality of global industrial fishing, unregulated fishing has largely escaped scrutiny. Here, we evaluate the unregulated nature of global squid fisheries using AIS data and nighttime imagery of the globalized fleet of light-luring squid vessels. We find that this fishery is extensive, fishing 149,000 to 251,000 vessel days annually, and that effort increased 68% over the study period 2017-2020. Most vessels are highly mobile and fish in multiple regions, largely (86%) in unregulated areas. While scientists and policymakers express concerns over the declining abundance of squid stocks globally and regionally, we find a net increase in vessels fishing squid globally and spatial expansion of effort to novel areas. Since fishing effort is static in areas with increasing management, and rising in unmanaged areas, we suggest actors may take advantage of fragmented regulations to maximize resource extraction. Our findings highlight a profitable, but largely unregulated fishery, with strong potential for improved management.


Assuntos
Decapodiformes , Pesqueiros , Animais , Caça , Alimentos Marinhos , Indústrias , Conservação dos Recursos Naturais
4.
Artigo em Inglês | MEDLINE | ID: mdl-35627588

RESUMO

The coronavirus disease pandemic has afforded dental professionals an opportunity to reconsider infection control during treatment. We investigated the efficacy of combining extraoral high-volume evacuators (eHVEs) with preprocedural mouth rinsing in reducing aerosol contamination by ultrasonic scalers. A double-masked, two-group, crossover randomized clinical trial was conducted over eight weeks. A total of 10 healthy subjects were divided into two groups; they received 0.5% povidone-iodine (PI), essential oil (EO), or water as preprocedural rinse. Aerosols produced during ultrasonic scaling were collected from the chest area (PC), dentist's mask, dentist's chest area (DC), bracket table, and assistant's area. Bacterial contamination was assessed using colony counting and adenosine triphosphate assays. With the eHVE 10 cm away from the mouth, bacterial contamination by aerosols was negligible. With the eHVE 20 cm away, more dental aerosols containing bacteria were detected at the DC and PC. Mouth rinsing decreased viable bacterial count by 31-38% (PI) and 22-33% (EO), compared with no rinsing. The eHVE prevents bacterial contamination when close to the patient's mouth. Preprocedural mouth rinsing can reduce bacterial contamination where the eHVE is positioned away from the mouth, depending on the procedure. Combining an eHVE with preprocedural mouth rinsing can reduce bacterial contamination in dental offices.


Assuntos
Anti-Infecciosos Locais , Antissépticos Bucais , Aerossóis , Microbiologia do Ar , Anti-Infecciosos Locais/uso terapêutico , Bactérias , Humanos , Antissépticos Bucais/uso terapêutico , Ultrassom
5.
PLoS One ; 12(11): e0188565, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29182651

RESUMO

The eastern Bering Sea has a vast continental shelf, which contains various endangered marine mammals and large fishery resources. Recently, high numbers of toxic A. tamarense resting cysts were found in the bottom sediment surface of the eastern Bering Sea shelf, suggesting that the blooms have recently occurred. However, little is known about the presence of A. tamarense vegetative cells in the eastern Bering Sea. This study's goals were to detect the occurrence of A. tamarense vegetative cells on the eastern Bering Sea shelf and to find a relationship between environmental factors and their presence. Inter-annual field surveys were conducted to detect A. tamarense cells and environmental factors, such as nutrients, salinity, chlorophyll a, and water temperature, along a transect line on the eastern Bering Sea shelf during the summers of 2004, 2005, 2006, 2009, 2012, and 2013. A. tamarense vegetative cells were detected during every sampling year, and their quantities varied greatly from year to year. The maximum cell densities of A. tamarense observed during the summers of 2004 and 2005 were much higher than the Paralytic shellfish poisoning warning levels, which are greater than 100-1,000 cells L-1, in other subarctic areas. Lower quantities of the species occurred during the summers of 2009, 2012, and 2013. A significant positive correlation between A. tamarense quantity and water temperature and significant negative correlations between A. tamarense quantity and nutrient concentrations (of phosphate, silicate, and nitrite and nitrate) were detected in every sampling period. The surface- and bottom-water temperatures varied significantly from year to year, suggesting that water temperatures, which have been known to affect the cell growth and cyst germination of A. tamarense, might have affected the cells' quantities in the eastern Bering Sea each summer. Thus, an increase in the Bering Sea shelf's water temperature during the summer will increase the frequency and scale of toxic blooms and the toxin contamination of plankton feeders. This poses serious threats to humans and the marine ecosystem.


Assuntos
Dinoflagellida/metabolismo , Eutrofização , Água do Mar/microbiologia
6.
Neurosci Lett ; 653: 25-30, 2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28526325

RESUMO

Multiple-EGF like domains 10 (MEGF10) is the mammalian homologue of Draper, a Drosophila phagocytosis receptor that plays an important role in synapse elimination and cell type-specific recognition. However, the expression and function of MEGF10 in the brain remain to be elucidated. Therefore, we aimed to clarify the regions and types of neurons that express MEGF10 in the brain, and to determine whether cells expressing MEGF10 possess phagocytic abilities. Our results indicated that MEGF10 is expressed in cholinergic and glutamatergic neurons of the cortex, hippocampus, and substantia nigra. Furthermore, the ratio of neurons expressing MEGF10 was higher in the cortex and hippocampus of hAPP transgenic mice than in those of wild-type mice. Phagocytic activity was also observed in neuronal cells expressing MEGF10. Thus, our results indicate that MEGF10 may be responsible for phagocytic activity targeted toward unwanted substances such as amyloid in cholinergic and glutamatergic neurons.


Assuntos
Encéfalo/metabolismo , Neurônios Colinérgicos/metabolismo , Proteínas de Membrana/metabolismo , Neurônios/metabolismo , Animais , Astrócitos , Linhagem Celular Tumoral , Ácido Glutâmico , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Fagocitose , Ratos
7.
J AOAC Int ; 97(3): 837-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25051632

RESUMO

A ready-made dry medium method for aerobic count, the MediCa AC method, was compared to the AOAC Official Method 966.23, Microbiological Methods, for seven different heat-processed meat matrixes: cooked roast beef, Chinese barbecued pork (barbecued pork seasoned with honey-based sauce), bacon, cooked ham, frankfurter (made from beef and pork), and boiled and cooked pork sausage. The 95% confidence interval for the mean difference between the two methods at each contamination level for each matrix fell within the range of -0.50 to 0.50, and no statistical difference was observed at all three contamination levels for five matrixes. These results demonstrate that the Medi-Ca AC method is a reasonable alternative to the AOAC 966.23 method for cooked meat products.


Assuntos
Bactérias Aeróbias/isolamento & purificação , Carga Bacteriana/métodos , Carne/microbiologia
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