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1.
Mar Pollut Bull ; 203: 116491, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754321

RESUMEN

Endosymbionts (Symbiodiniaceae) play a vital role in the health of corals. Seawater pollution can harm these endosymbionts and dispersants used during oil spill cleanup can be extremely toxic to these organisms. Here, we examined the impact of oil and a specific dispersant, Corexit-9500, on two representative endosymbionts - Symbiodinium and Cladocopium - from the Southwestern endemic coral Mussismilia braziliensis. The survival and photosynthetic potential of the endosymbionts decreased dramatically after exposure to the dispersant and oil by ~25 % after 2 h and ~50 % after 7 days. Low concentrations of dispersant (0.005 ml/l) and dispersed oil (Polycyclic Aromatic Hydrocarbons, 1132 µg/l; Total Petroleum Hydrocarbons, 595 µg/l) proved highly toxic to both Symbiodinium and Cladocopium. These levels triggered a reduction in growth rate, cell size, and cell wall thickness. After a few hours of exposure, cellular organelles were damaged or destroyed. These acute toxic effects underline the fragile nature of coral endosymbionts.


Asunto(s)
Antozoos , Dinoflagelados , Contaminación por Petróleo , Petróleo , Simbiosis , Contaminantes Químicos del Agua , Antozoos/efectos de los fármacos , Antozoos/fisiología , Animales , Petróleo/toxicidad , Dinoflagelados/fisiología , Dinoflagelados/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Lípidos , Tensoactivos/toxicidad
2.
ACS Biomater Sci Eng ; 10(3): 1808-1818, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38411100

RESUMEN

Bacteria are an old concern to human health, as they are responsible for nosocomial infections, and the number of antibiotic-resistant microorganisms keeps growing. Copper is known for its intrinsic biocidal properties, and therefore, it is a promising material to combat infections when added to surfaces. However, its biocidal properties in the presence of light illumination have not been fully explored, especially regarding the use of microsized particles since nanoparticles have taken over all fields of research and subjugated microparticles despite them being abundant and less expensive. Thus, the present work studied the bactericidal properties of metallic copper particles, in microscale (CuMPs) and nanoscale (CuNPs), in the absence of light and under white LED light illumination. The minimum bactericidal concentration (MBC) of CuMPs against Staphylococcus aureus that achieved a 6-log reduction was 5.0 and 2.5 mg mL-1 for assays conducted in the absence of light and under light illumination, respectively. Similar behavior was observed against Escherichia coli. The bactericidal activity under illumination provided a percentage increase in log reduction values of 65.2% for S. aureus and 166.7% for E. coli when compared to the assays under dark. This assay reproduced the testing CuNPs, which showed superior bactericidal activity since the concentration of 2.5 mg mL-1 promoted a 6-log reduction of both bacteria even under dark. Its superior bactericidal activity, which overcame the effect of illumination, was expected once the nanoscale facilitated the interaction of copper within the surface of bacteria. The results from MBC were supported by fluorescence microscopy and atomic absorption spectroscopy. Therefore, CuMPs and CuNPs proved to have size- and dose-dependent biocidal activity. However, we have shown that CuMPs photoactivity is competitive compared to that of CuNPs, allowing their application as a self-cleaning material for disinfection processes assisted by conventional light sources without additives to contain the spread of pathogens.


Asunto(s)
Cobre , Staphylococcus aureus , Humanos , Cobre/farmacología , Cobre/química , Escherichia coli , Iluminación , Antibacterianos/farmacología , Antibacterianos/química , Bacterias
3.
Front Microbiol ; 13: 973980, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36299729

RESUMEN

Corals are treatened by global warming. Bleaching is one immediate effect of global warming, resulting from the loss of photosynthetic endosymbiont dinoflagellates. Understanding host-symbiont associations are critical for assessing coral's habitat requirements and its response to environmental changes. Cladocopium (formerly family Symbiodiniaceae clade C) are dominant endosymbionts in the reef-building coral, Mussismilia braziliensis. This study aimed to investigate the effect of temperature on the biochemical and cellular features of Cladocopium. Heat stress increased oxygen (O2) and decreased proteins, pigments (Chla + Chlc2), hexadecanoic acid- methyl ester, methyl stearate, and octadecenoic acid (Z)- methyl ester molecules. In addition, there was an increase in neutral lipids such as esterified cholesterol and a decrease in free fatty acids that may have been incorporated for the production of lipid droplets. Transmission electron microscopy (TEM) demonstrated that Cladocopium cells subjected to heat stress had thinner cell walls, deformation of chloroplasts, and increased lipid droplets after 3 days at 28°C. These findings indicate that thermal stress negatively affects isolated Cladocopium spp. from Mussismilia host coral.

4.
Sci Total Environ ; 847: 157474, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-35868367

RESUMEN

Sponges have co-evolved with microbes for over 400 myr. Previous studies have demonstrated that sponges can be classified according to the abundance of microbes in their tissues as Low Microbial Abundance (LMA) and High Microbial Abundance (HMA). While LMA sponges rely mainly on water column microbes, HMA appear to rely much more on symbiotic fermentative and autotrophic microbes maintained in their tissues. However, it is unclear if this pattern holds when comparing different species of tropical sponges under extreme nutrient conditions and sediment loads in the water column, such as the Great Amazon Reef System (GARS), which covers an area of ~56,000 km2 off the Amazon River mouth. Sponges are the major GARS benthic components. However, these sponges' microbiome across the GARS is still unknown. Here, we investigated water quality, isotopic values (δ13C and δ15N), metagenomic and lipidomic profiles of sponges obtained from different sectors throughout the GARS. >180 million shotgun metagenomic reads were annotated, covering 22 sponge species. Isotopic and lipidomic analyses suggested LMA sponges rely on the Amazon River Plume for nutrition. HMA sponges (N = 15) had higher Roseiflexus and Nitrospira abundance, whereas LMA sponges (N = 7) had higher Prochlorococcus and Pelagibacter abundance. Functional data revealed that the LMA sponge microbiomes had greater number of sequences related to phages and prophages as well as electron transport and photophosphorylation which may be related to photosynthetic processes associated with the Prochlorococcus and Synechococcus found in the LMA. The higher phages abundance in LMA sponges could be related to these holobionts' reduced defense towards phage infection. Meanwhile, HMA sponge microbiomes had higher Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR abundance, which may be involved in defense against phage infection. This study sheds light on the nutrient fluxes and microbes from the Amazon River plume into the sponge holobionts.


Asunto(s)
Poríferos , Ríos , Animales , Nutrientes , Filogenia , ARN Ribosómico 16S
5.
Nutr Rev ; 80(3): 428-438, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34969067

RESUMEN

CONTEXT: Epidemiological studies suggest an association between vitamin D deficiency and anemia. Evidence of this relationship in pregnant women, however, is scarce. OBJECTIVE: The aim of this systematic review was to investigate the association between vitamin D deficiency and gestational anemia through observational studies. DATA SOURCES: The PubMed, Scopus, Web of Science, ScienceDirect, Embase, and Virtual Health Library databases were searched from inception to April 2021. STUDY SELECTION: Original articles reporting observational studies that investigated the association between vitamin D deficiency and gestational anemia were included. Articles that did not have an abstract, as well as reviews articles, experimental studies, and editorials, were excluded. Two reviewers independently performed study selection, data extraction, and assessment of study quality. Disagreements between the reviewers were resolved by a third reviewer. DATA EXTRACTION: Study quality was assessed by 2 scales. Data were extracted from eligible studies and arranged in a 2 × 2 table. Odds ratios with 95% confidence intervals for the risk of the outcome were estimated using a fixed-effect model. RESULTS: In total, 985 studies were retrieved, of which 17 were included in the systematic review: 11 cohort studies, 3 case-control studies, and 3 cross-sectional studies. For the meta-analysis, 8 studies with a total of 6530 women were included. There was a 61% increase in the odds of anemia in pregnant women with vitamin D deficiency (OR = 1.61; 95%CI, 1.41-1.83; I2 = 48%). CONCLUSIONS: Vitamin D deficiency may be a risk factor for anemia in pregnant women. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42020182697.


Asunto(s)
Anemia , Deficiencia de Vitamina D , Anemia/epidemiología , Anemia/etiología , Estudios Transversales , Femenino , Humanos , Embarazo , Mujeres Embarazadas , Vitamina D , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiología
6.
Vet Med Sci ; 4(4): 280-287, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29963762

RESUMEN

Bluetongue (BT), caused by Bluetongue virus (BTV), is a disease that affects ruminants such as cattle, sheep, goats and deer. BTV is transmitted by female midges of the genus Culicoides. In Brazil, information on the prevalence of BTV in cattle is limited, so the objective of this work was to identify BTV serotypes in cattle. The State of São Paulo was divided into seven cattle-producing regions, and in each of them, 300 cattle farms were randomly selected. One animal from each farm (out of a total of 1,598 farms) was selected and its sera tested by virus neutralization technique against BTV serotypes (1-24 and 26) for determining antibody titre. Moreover, for each sampled farm, an epidemiological questionnaire was submitted to verify the type of cattle production and the zootechnical and sanitary practices carried out, which could be associated with a higher risk of BTV infection. In this study, antibodies (percentage, [95% confidence interval]) were identified against 11 serotypes: BTV-1 (22.15%, [15.72-27.92]), BTV-2 (31.03%, [26.65-37.98]), BTV-3 (18.96%, [12.42-24.90]), BTV-4 (24.90% [19.41-29.12]), BTV-9 (6.82%, [1.45-11.72]), BTV-12 (7.50%, [2.82-12.51]), BTV-17 (23.90%, [17.35-29.35]), BTV-19 (10.20%, [4.62-5.56]), BTV-21 (30.66%, [25.00-36.00]), BTV-22 (12.14%, [5.91-18.55]), BTV-26 (57.00%, [51.41-63.59]). In this study, for the first time in Brazil serological evidence of the presence of serotypes BTV-2, BTV-9, BTV-21 and BTV-26 is reported. The variable 'new cattle entering herd' was considered a risk factor for the occurrence of infection (OR = 2.183, 95% CI = 1.6-2.9).


Asunto(s)
Virus de la Lengua Azul/clasificación , Lengua Azul/epidemiología , Enfermedades de los Bovinos/epidemiología , Crianza de Animales Domésticos , Animales , Virus de la Lengua Azul/inmunología , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/virología , Estudios Transversales , Modelos Logísticos , Prevalencia , Factores de Riesgo , Serogrupo
7.
Ticks Tick Borne Dis ; 9(4): 850-859, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29567146

RESUMEN

Tick infestation in cattle reflects the main cause of economic loss to cattle producers. This is due to several reasons but mainly to their ability to feed on blood and generate a huge amount of eggs. Lipid transport in arthropods is achieved by highly specialized hemolymphatic lipoproteins, which resemble those described in vertebrate blood. Such lipoproteins continuously deliver lipids through the blood to growing eggs. The injection of radioactive [3H] palmitic acid into tick hemocoel showed that the gut, ovary, fat body and Gene's organ were the main organs of incorporation of this labeled fatty acid. The rate of [3H] palmitic acid incorporation by the organs was high up to 30 min after injection. The [3H] palmitic acid incorporated by these organs was later found in phospholipids and neutral lipids. Here, we describe the purification and characterization of a key player of lipid dynamics in tick hemolymph. The Rhipicephalus microplus lipid-apolipoprotein complex (RmLCP) is a new high-density lipoprotein (1.18 g/mL), which accounts for over 90% of [3H] palmitic acid present in the hemolymph. It has a native molecular weight of 420 kDa and is composed of one subunit of 122 kDa. Protein identification analysis of RmLPC subunit showed two better hits: vitellogenin 2 (23% protein coverage) and vitellogenin 5 (29% protein coverage), respectively and similarities with hemolymphatic apolipoproteins of arachnids such as the tick Ixodes scapularis (80%), the mite Galendromus occidentalis (44%) and the spider Parasteatoda tepidariorum (43%) and also for the insects Locusta migratoria (45%), Drosophila melanogaster (42%) and Manduca sexta (47%) to vitellogenin 2 and tick Ixodes scapularis (83%), the crab Limulus polyphemus (55%) and the oyster Crassostrea gigas (55%) to vitellogenin 5. Furthermore, it shows a distinct lipid composition from most arthropod lipoproteins, being composed of 40% free cholesterol, 27% phospholipids, 20% triacylglycerol and 15% hydrocarbons. In addition to binding most hemolymphatic fatty acids, this lipoprotein also binds and transports free cholesterol. In conclusion, the present study provides insight into the macromolecules involved in arachnid metabolism, which have significant potential for future use for the biological control of ticks.


Asunto(s)
Proteínas Portadoras/química , Lipoproteínas/química , Lipoproteínas/metabolismo , Rhipicephalus/metabolismo , Infestaciones por Garrapatas/veterinaria , Animales , Proteínas Portadoras/metabolismo , Bovinos/parasitología , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/parasitología , Colesterol/metabolismo , Ácidos Grasos/metabolismo , Femenino , Ixodes/metabolismo , Lipoproteínas/aislamiento & purificación , Fosfolípidos/metabolismo , Rhipicephalus/anatomía & histología , Rhipicephalus/química , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología , Vitelogeninas/química , Vitelogeninas/genética
8.
J Vet Diagn Invest ; 25(1): 125-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23345275

RESUMEN

A cross-sectional study was carried out to determine the flock-level seroprevalence of Caprine herpesvirus 1 (CpHV-1) and Bovine herpesvirus 1 (BoHV-1) and 2 (BoHV-2) and risk factors associated with CpHV-1 in dairy goat flocks from a semiarid region of northeastern Brazil. A total of 1,034 serum samples from 110 flocks were collected from March 2009 through March 2010. A structured questionnaire focusing on variables related to risk factors for CpHV-1 infection was given to each farmer at the time of blood collection. Antibodies against CpHV-1, BoHV-1, and BoHV-2 were detected by neutralization tests. The flock-level prevalences of CpHV-1, BoHV-1, and BoHV-2 were 89.1% (98/110; 95% confidence interval [CI]: 81.7-94.2), 80% (88/110; 95% CI: 71.3-87), and 4.5% (5/110; 95% CI: 1.5-10.3), respectively. Frequencies of seropositive animals were 36.6% (379/1,034), 25.8% (267/1,034), and 0.6% (6/1,034) for CpHV-1, BoHV-1, and BoHV-2, respectively. The use of natural mating was identified as a risk factor associated with CpHV-1 flock-level prevalence (P = 0.001). It is suggested that adoption of veterinary services and active surveillance of the at-risk flocks in the study region should be initiated to reduce the prevalence of herpesvirus infections.


Asunto(s)
Anticuerpos Antivirales/inmunología , Enfermedades de las Cabras/virología , Infecciones por Herpesviridae/veterinaria , Herpesvirus Bovino 1/aislamiento & purificación , Varicellovirus/aislamiento & purificación , Animales , Anticuerpos Antivirales/sangre , Brasil/epidemiología , Estudios Transversales , Femenino , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/inmunología , Cabras , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/virología , Herpesvirus Bovino 1/inmunología , Modelos Logísticos , Análisis Multivariante , Pruebas de Neutralización/veterinaria , Factores de Riesgo , Estudios Seroepidemiológicos , Encuestas y Cuestionarios , Varicellovirus/inmunología
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