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1.
Mucosal Immunol ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729611

RESUMO

Resident memory T cells (TRMs) help control local immune homeostasis and contribute to tissue protective immune responses. The local cues that guide their differentiation and localization are poorly defined. We demonstrate that MAdCAM-1, a ligand for the gut homing receptor α4ß7 integrin, in the presence of retinoic acid and TGF-ß provide a costimulatory signal that induces blood CD8+ T cells to adopt a TRM -like phenotype. These cells express CD103 (integrin αE) and CD69, the two major TRM cell surface markers, along with CD101. They also express CCR5, CCR9 and α4ß7, three receptors associated with gut homing. A subset also express E-cadherin, a ligand for αEß7. Fluorescent lifetime imaging indicated an αEß7 and E-cadherin cis interaction on the plasma membrane. This report advances our understanding of the signals that drive the differentiation of CD8+ T cells into TRMs and provides a means to expand these cells in vitro, thereby affording an avenue to generate more effective tissue specific immunotherapies.

2.
Heliyon ; 10(7): e28851, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596029

RESUMO

Microplastics (MPs) have been identified as a major potential threat to the biota and human health. Despite the exponential increase in MP research worldwide, few studies have focused on the extensive Amazon biome. To assess research priorities, the present study reviewed and summarized the available scientific knowledge on MPs in the Amazon, in addition to analyzing population and waste-management data, to evaluate potential sources of MPs in the hydrographic system. Poor sanitation conditions are a main source of MPs for the vast hydrographic basin, and, consequently, for the adjacent ocean. Secondary MPs predominated, mostly fibers (96% of debris), composed of polyamide (32%). Mean MP concentrations ranged from 0.34 to 38.3 particles.individual-1 in biota, 5 to 476,000 particles.m-3 in water, and 492.5 to 1.30848 × 107 particles.m-3 in sediment, values in close comparison with those found in areas profoundly affected by anthropogenic pollution. MPs were widespread in a range of Amazonian environments and species, and negative effects are probably occurring at various ecological levels. However, limited research, methodological constraints, flaws and the lack of standardization, combined with the continental dimensions of the Amazon, hampers the collection of the fundamental knowledge needed to reliably evaluate the impacts and implement effective mitigation measures. There is an urgent need to expand scientific data available for the region, improving local research infrastructure, and training and deploying local researchers.

3.
BMC Bioinformatics ; 25(1): 125, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519883

RESUMO

In the battle of the host against lentiviral pathogenesis, the immune response is crucial. However, several questions remain unanswered about the interaction with different viruses and their influence on disease progression. The simian immunodeficiency virus (SIV) infecting nonhuman primates (NHP) is widely used as a model for the study of the human immunodeficiency virus (HIV) both because they are evolutionarily linked and because they share physiological and anatomical similarities that are largely explored to understand the disease progression. The HIHISIV database was developed to support researchers to integrate and evaluate the large number of transcriptional data associated with the presence/absence of the pathogen (SIV or HIV) and the host response (NHP and human). The datasets are composed of microarray and RNA-Seq gene expression data that were selected, curated, analyzed, enriched, and stored in a relational database. Six query templates comprise the main data analysis functions and the resulting information can be downloaded. The HIHISIV database, available at  https://hihisiv.github.io , provides accurate resources for browsing and visualizing results and for more robust analyses of pre-existing data in transcriptome repositories.


Assuntos
Infecções por HIV , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Humanos , Vírus da Imunodeficiência Símia/genética , HIV , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Progressão da Doença , Imunidade , Expressão Gênica
4.
Cells ; 13(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38334595

RESUMO

The communication between neural stem cells (NSCs) and surrounding astrocytes is essential for the homeostasis of the NSC niche. Intercellular mitochondrial transfer, a unique communication system that utilizes the formation of tunneling nanotubes for targeted mitochondrial transfer between donor and recipient cells, has recently been identified in a wide range of cell types. Intercellular mitochondrial transfer has also been observed between different types of cancer stem cells (CSCs) and their neighboring cells, including brain CSCs and astrocytes. CSC mitochondrial transfer significantly enhances overall tumor progression by reprogramming neighboring cells. Despite the urgent need to investigate this newly identified phenomenon, mitochondrial transfer in the central nervous system remains largely uncharacterized. In this study, we found evidence of intercellular mitochondrial transfer from human NSCs and from brain CSCs, also known as brain tumor-initiating cells (BTICs), to astrocytes in co-culture experiments. Both NSC and BTIC mitochondria triggered similar transcriptome changes upon transplantation into the recipient astrocytes. In contrast to NSCs, the transplanted mitochondria from BTICs had a significant proliferative effect on the recipient astrocytes. This study forms the basis for mechanistically deciphering the impact of intercellular mitochondrial transfer on recipient astrocytes, which will potentially provide us with new insights into the mechanisms of mitochondrial retrograde signaling.


Assuntos
Neoplasias Encefálicas , Células-Tronco Neurais , Humanos , Astrócitos/metabolismo , Células-Tronco Neurais/metabolismo , Encéfalo/metabolismo , Mitocôndrias/metabolismo , Neoplasias Encefálicas/metabolismo , Células-Tronco Neoplásicas/patologia
5.
Heliyon ; 10(3): e25474, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38327440

RESUMO

Since human papillomavirus (HPV) is recognized as the causative agent of cervical cancer and associated with anogenital non-cervical and oropharyngeal cancers, the characterization of the HPV types circulating in different geographic regions is an important tool in screening and prevention. In this context, this study compared four methodologies for HPV detection and genotyping: real-time PCR (Cobas® HPV test), nested PCR followed by conventional Sanger sequencing, reverse hybridization (High + Low PapillomaStrip® kit) and next-generation sequencing (NGS) at an Illumina HiSeq2500 platform. Cervical samples from patients followed at the Family Health Strategy from Juiz de Fora, Minas Gerais, Brazil, were collected and subjected to the real-time PCR. Of those, 114 were included in this study according to the results obtained with the real-time PCR, considered herein as the gold standard method. For the 110 samples tested by at least one methodology in addition to real-time PCR, NGS showed the lowest concordance rates of HPV and high-risk HPV identification compared to the other three methods (67-75 %). Real-time PCR and Sanger sequencing showed the highest rates of concordance (97-100 %). All methods differed in their sensitivity and specificity. HPV genotyping contributes to individual risk stratification, therapeutic decisions, epidemiological studies and vaccine development, supporting approaches in prevention, healthcare and management of HPV infection.

6.
Int. j. cardiovasc. sci. (Impr.) ; 37: e20230065, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534617

RESUMO

Abstract Background Congenital heart diseases (CHD) are one of the most prevalent malformations, and the screening tests to identify critical congenital heart disease (CCHD) is the pulse oximetry test, with subsequent investigation and treatment. Objective To quantify positive pulse oximetry tests and verify the prevalence of CCHD detected by it in asymptomatic newborns, ≥35 gestational weeks, in a Brazilian maternity hospital. Methodology This is an observational, retrospective, quantitative, analytical and cross-sectional study, conducted from October 2020 to May 2022, in a maternity hospital in southern Brazil, through the collection of records of positive oximetry pulse tests, following the norms of screening CCHD test of the Brazilian Society of Pediatrics (SBP), after they were evaluated with echocardiography for confirmation or exclusion of CHD. Results A total of 5,667 newborns were evaluated in this study, according to the inclusion criteria; 0.17% (n = 10) had a positive pulse oximetry test. Regarding the results of the echocardiography of the neonates with a positive test, two were normal, seven were cases of patent foramen ovale (PFO), and one was a case (0,017%) with interatrial communication (IAC) diagnosis. In the same period, five neonates with CCHD were born, symptomatic, diagnosed by physical examination, and referred to neonatal intensive care units (NICU) before taking the neonatal cardiac screening (< 24 hours of life). Conclusion The prevalence of positive pulse oximetry tests was 0.17% and none CCHD was detected. Five cases of CCHD were born in this period, but they were diagnosed before the recommend time to perform the screening test.

7.
PLoS Pathog ; 19(12): e1011860, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38064524

RESUMO

The CD4 receptor, by stabilizing TCR-MHC II interactions, plays a central role in adaptive immunity. It also serves as the HIV docking receptor. The HIV gp120 envelope protein binds directly to CD4. This interaction is a prerequisite for viral entry. gp120 also binds to ⍺4ß7, an integrin that is expressed on a subset of memory CD4+ T cells. HIV tropisms for CD4+ T cells and gut tissues are central features of HIV pathogenesis. We report that CD4 binds directly to ⍺4ß7 in a dynamic way, consistent with a cis regulatory interaction. The molecular details of this interaction are related to the way in which gp120 interacts with both receptors. Like MAdCAM-1 and VCAM-1, two recognized ligands of ⍺4ß7, the binding interface on CD4 includes 2 sites (1° and accessory), distributed across its two N-terminal IgSF domains (D1 and D2). The 1° site includes a sequence in the G ß-strand of CD4 D2, KIDIV, that binds directly to ⍺4ß7. This pentapeptide sequence occurs infrequently in eukaryotic proteins. However, a closely related and conserved sequence, KLDIV, appears in the V2 domain of gp120. KLDIV mediates gp120-⍺4ß7 binding. The accessory ⍺4ß7 binding site on CD4 includes Phe43. The Phe43 aromatic ring protrudes outward from one edge of a loop connecting the C'C" strands of CD4 D1. Phe43 is a principal contact for HIV gp120. It interacts with conserved residues in the recessed CD4 binding pocket. Substitution of Phe43 abrogates CD4 binding to both gp120 and ⍺4ß7. As such, the interactions of gp120 with both CD4 and ⍺4ß7 reflect elements of their interactions with each other. These findings indicate that gp120 specificities for CD4 and ⍺4ß7 are interrelated and suggest that selective pressures which produced a CD4 tropic virus that replicates in gut tissues are linked to a dynamic interaction between these two receptors.


Assuntos
Infecções por HIV , Integrinas , Humanos , Integrinas/metabolismo , Sítios de Ligação , Antígenos CD4 , Linfócitos T CD4-Positivos/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo
8.
Genet Mol Biol ; 46(4): e20230015, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38051353

RESUMO

A complete genome of the first anellovirus infecting the wild felid Leopardus pardalis (ocelot) and a partial genome were assembled and annotated through high-throughput sequencing protocols followed by Sanger sequencing validation. The full-length virus obtained comprises 2,003 bp, while the partial genome comprises 1,224 bp. Phylogenetic analysis grouped these two sequences in two distinct clusters related to previously described Felidae anelloviruses. The ORF1 of the partial genome was identified as a new species provisionally called Torque teno ocelot virus, with 53.6% identity with its sister lineage. The complete genome was inferred as a new representative of the Torque teno felid virus 3 species, with 73.28% identity to the closest reference. This study expands known virus diversity and the host span of anelloviruses.

9.
Arq Neuropsiquiatr ; 81(11): 989-999, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38035584

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) has emerged as a public health emergency worldwide, predominantly affecting the respiratory tract. However, evidence supports the involvement of extrapulmonary sites, including reports of intracranial hemorrhages. OBJECTIVE: To describe six original cases and review the literature on intracranial hemorrhages in patients diagnosed with COVID-19 by molecular methods. METHODS: A systematic literature review was performed on MEDLINE, PubMed, and NCBI electronic databases to identify eligible studies. Of the total 1,624 articles retrieved, only 53 articles met the inclusion criteria. RESULTS: The overall incidence of intracranial hemorrhage in patients hospitalized for COVID-19 was 0.26%. In this patient group, the mean age was 60 years, and the majority were male (68%) with initial respiratory symptoms (73%) and some comorbidity. Before the diagnosis of hemorrhage, 43% of patients were using anticoagulants, 47.3% at therapeutic doses. The intraparenchymal (50%) was the most affected compartment, followed by the subarachnoid (34%), intraventricular (11%), and subdural (7%). There was a predominance of lobar over non-lobar topographies. Multifocal or multicompartmental hemorrhages were described in 25% of cases. Overall mortality in the cohort studies was 44%, while around 55% of patients were discharged from hospital. CONCLUSION: Despite the unusual association, the combination of these two diseases is associated with high rates of mortality and morbidity, as well as more severe clinicoradiological presentations. Further studies are needed to provide robust evidence on the exact pathophysiology behind the occurrence of intracranial hemorrhages after COVID-19 infection.


ANTECEDENTES: A COVID-19 emergiu como uma emergência de saúde pública em todo o mundo, proporcionando lesão principalmente do trato respiratório. No entanto, várias evidências apontam para acometimento de sítios extrapulmonares, incluindo relatos de hemorragias intracranianas. OBJETIVO: Descrever seis casos originais e revisar a literatura sobre hemorragias intracranianas em pacientes com diagnostico de COVID-19 por métodos moleculares. MéTODOS: A revisão sistemática da literatura foi feita nas bases de dados eletrônicas da MEDLINE, PubMed e NCBI para identificar os estudos elegíveis. Do total de 1.624 artigos recuperados, apenas 53 artigos preencheram os critérios de inclusão. RESULTADOS: A incidência geral de hemorragia intracraniana nos pacientes internados por COVID-19 foi de 0,26%. A média de idade foi de 60 anos, e a maioria dos pacientes era do sexo masculino (68%) com sintomas respiratórios iniciais (73%) e alguma comorbidade. Antes do diagnóstico de hemorragia, 43% estavam em uso de anticoagulantes, 47,3% destes em doses terapêuticas. O compartimento mais acometido foi o intraparenquimatoso (50%), seguido do subaracnoideo (34%), intraventricular (11%) e subdural (7%). Houve predomínio de topografias lobares sobre as não-lobares. Hemorragias multifocais ou multicompartimentais foram descritas em 25% dos casos. A mortalidade geral nos estudos de coorte foi de 44%, enquanto houve alta hospitalar em cerca de 55% dos pacientes. CONCLUSãO: Apesar da associação incomum, a combinação dessas doenças está relacionada com altas taxas de mortalidade e morbidade, bem como apresentações clínico-radiológicas mais graves. Mais estudos são necessários para oferecer evidências robustas sobre a fisiopatologia exata por trás da ocorrência de hemorragias intracranianas após infecção por COVID-19.


Assuntos
COVID-19 , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , COVID-19/complicações , Hemorragias Intracranianas/etiologia , Hemorragia , Anticoagulantes/uso terapêutico , Estudos de Coortes
10.
Polymers (Basel) ; 15(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37959893

RESUMO

Accurately printing customizable scaffolds is a challenging task because of the complexity of bone tissue composition, organization, and mechanical behavior. Graphene oxide (GO) and poly-L-lactic acid (PLLA) have drawn attention in the field of bone regeneration. However, as far as we know, the Fischer-Koch model of the GO/PLLA association for three-dimensional (3D) printing was not previously reported. This study characterizes the properties of GO/PLLA-printed scaffolds in order to achieve reproducibility of the trabecula, from virtual planning to the printed piece, as well as its response to a cell viability assay. Fourier-transform infrared and Raman spectroscopy were performed to evaluate the physicochemical properties of the nanocomposites. Cellular adhesion, proliferation, and growth on the nanocomposites were evaluated using scanning electron microscopy. Cell viability tests revealed no significant differences among different trabeculae and cell types, indicating that these nanocomposites were not cytotoxic. The Fischer Koch modeling yielded satisfactory results and can thus be used in studies directed at diverse medical applications, including bone tissue engineering and implants.

11.
Arq. neuropsiquiatr ; 81(11): 989-999, Nov. 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1527894

RESUMO

Abstract Background Coronavirus disease 2019 (COVID-19) has emerged as a public health emergency worldwide, predominantly affecting the respiratory tract. However, evidence supports the involvement of extrapulmonary sites, including reports of intracranial hemorrhages. Objective To describe six original cases and review the literature on intracranial hemorrhages in patients diagnosed with COVID-19 by molecular methods. Methods A systematic literature review was performed on MEDLINE, PubMed, and NCBI electronic databases to identify eligible studies. Of the total 1,624 articles retrieved, only 53 articles met the inclusion criteria. Results The overall incidence of intracranial hemorrhage in patients hospitalized for COVID-19 was 0.26%. In this patient group, the mean age was 60 years, and the majority were male (68%) with initial respiratory symptoms (73%) and some comorbidity. Before the diagnosis of hemorrhage, 43% of patients were using anticoagulants, 47.3% at therapeutic doses. The intraparenchymal (50%) was the most affected compartment, followed by the subarachnoid (34%), intraventricular (11%), and subdural (7%). There was a predominance of lobar over non-lobar topographies. Multifocal or multicompartmental hemorrhages were described in 25% of cases. Overall mortality in the cohort studies was 44%, while around 55% of patients were discharged from hospital. Conclusion Despite the unusual association, the combination of these two diseases is associated with high rates of mortality and morbidity, as well as more severe clinicoradiological presentations. Further studies are needed to provide robust evidence on the exact pathophysiology behind the occurrence of intracranial hemorrhages after COVID-19 infection.


Resumo Antecedentes A COVID-19 emergiu como uma emergência de saúde pública em todo o mundo, proporcionando lesão principalmente do trato respiratório. No entanto, várias evidências apontam para acometimento de sítios extrapulmonares, incluindo relatos de hemorragias intracranianas. Objetivo Descrever seis casos originais e revisar a literatura sobre hemorragias intracranianas em pacientes com diagnostico de COVID-19 por métodos moleculares. Métodos A revisão sistemática da literatura foi feita nas bases de dados eletrônicas da MEDLINE, PubMed e NCBI para identificar os estudos elegíveis. Do total de 1.624 artigos recuperados, apenas 53 artigos preencheram os critérios de inclusão. Resultados A incidência geral de hemorragia intracraniana nos pacientes internados por COVID-19 foi de 0,26%. A média de idade foi de 60 anos, e a maioria dos pacientes era do sexo masculino (68%) com sintomas respiratórios iniciais (73%) e alguma comorbidade. Antes do diagnóstico de hemorragia, 43% estavam em uso de anticoagulantes, 47,3% destes em doses terapêuticas. O compartimento mais acometido foi o intraparenquimatoso (50%), seguido do subaracnoideo (34%), intraventricular (11%) e subdural (7%). Houve predomínio de topografias lobares sobre as não-lobares. Hemorragias multifocais ou multicompartimentais foram descritas em 25% dos casos. A mortalidade geral nos estudos de coorte foi de 44%, enquanto houve alta hospitalar em cerca de 55% dos pacientes. Conclusão Apesar da associação incomum, a combinação dessas doenças está relacionada com altas taxas de mortalidade e morbidade, bem como apresentações clínico-radiológicas mais graves. Mais estudos são necessários para oferecer evidências robustas sobre a fisiopatologia exata por trás da ocorrência de hemorragias intracranianas após infecção por COVID-19.

12.
Mar Pollut Bull ; 196: 115654, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37839129

RESUMO

Recent arrivals of tar balls have been observed in several tropical beaches associated with the oceanic circulation that flows to the Brazilian continental shelf. Between August and September 2022, tar balls were collected in the northeastern coast of Brazil and analyzed. Nearly 90 % of the oils were colonized by barnacles, polychaetes, decapods, and algae. Most rafting organisms were Lepas anserifera with capitulum measuring 0.32 to 22.21 mm. Based on the growth rate of barnacles and the speed of the SEC it was estimated that tar balls were floating since July and August 2022 and traveled a maximum of 1938.82 km. The organisms and tar balls' possible origin is in the international waters, near to the meso-Atlantic ridge, known for oil tanker traffic. The tar balls, in addition to the oil-related impacts, can act as a vector of long-distance species dispersion, and it needs to raise an alert, considering the possible ecological impacts.


Assuntos
Meio Ambiente , Monitoramento Ambiental , Navios , Brasil
13.
Mar Environ Res ; 192: 106215, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37890231

RESUMO

Coral reefs in turbid waters have been hypothesized to be a refuge from climate change. These naturally occurring communities were brought into the spotlight because some of their species exhibited record levels of resistance to marine heatwaves (MHWs) by disturbance-tolerant corals. However, long-term monitoring data on the drivers of coral bleaching in these extreme reef habitats are scarce. Here, we describe the population structure and bleaching rates of a widespread and resilient coral (Siderastrea stellata). We examine the links between environmental factors, namely, rainfall, wind speed, turbidity, solar irradiance, sea surface temperature, MHWs, and coral bleaching status under the worst recorded drought cycle in the Tropical South Atlantic (2013-2015). We examined 2880 colonies, most of which (∼93%) fit in the size group of 2-10 cm, with a small number (∼1%) of larger and older colonies (>20 cm). The results indicated the absence of MHWs and normal sea surface temperature variations (between 26.6 °C and 29.3 °C), however, we detected an extreme rainfall deficit (30-40% less annual volume precipitation). In general, a high proportion (44-84%) of bleached colonies was found throughout the months when turbidity decreased. Siderastrea is the only reef-building coral that comprises this seascape with encrusting and low-relief colonies. During drought periods, cloudiness is reduced, turbidity and wind speed are reduced, and solar irradiance increase, driving coral bleaching in turbid reefs. However, episodic rainfall and higher wind speeds increase turbidity and decrease coral bleaching. Our hypothesis is that turbidity decreases during drought periods which increases bleaching risk to corals even without thermal stress. Our results suggest that turbidity may have related to wind and rainfall to provoke the coral bleaching phenomenon.


Assuntos
Antozoários , Branqueamento de Corais , Animais , Vento , Recifes de Corais , Ecossistema
14.
Chronic Stress (Thousand Oaks) ; 7: 24705470231207010, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37859939

RESUMO

Background: Social isolation (SI) and loneliness are major adult and adolescent health concerns, particularly in the coronavirus disease 2019 (COVID-19) era. Recent prospective cohort studies indicate that older women who experienced both SI and loneliness had a significantly higher risk of cardiovascular disease (CVD). Hypertension, a well-established risk factor for CVD, is more prevalent in elderly women than men. Furthermore, a lack of social relationships is strongly associated with an increased risk of hypertension in middle-aged and elderly women compared to men. Although this has not been extensively studied, adolescents and young adults who experience loneliness or SI may also be at risk for CVD and depression. The purpose of this study was to examine the effect of SI on blood pressure and depression-like behavior in young male and female mice. Methods: Weaned C57BL/6 mice were randomly assigned (n = 6/group/sex) to either group housing (GH) or SI. Animals in the SI group were housed in individual cages for 8 weeks with no view of other animals. The cages were kept in ventilated racks to prevent pheromone exposure and socially isolated animals had no cage enrichment. Results: SI increased systolic, diastolic, and mean arterial blood pressure in females and elevated heart rate in both sexes. Body weight gain was dramatically increased in socially isolated females but tended to decrease in socially isolated males. In the forced swim test, which detects depression-like behavior, there was no difference between groups in total immobility time. The latency to immobility, however, was significantly decreased in socially isolated females. Serum concentrations of corticosterone and metanephrine did not differ between socially isolated and group-housed females, but corticosterone levels were significantly reduced in socially isolated males. Conclusions: Our results indicate that 8 weeks of SI leads to significant changes in blood pressure and heart rate and mild changes in depression-like behavior in young mice, with females affected more than males.

15.
Environ Pollut ; 337: 122509, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37690465

RESUMO

Microplastic (MP) pollution has been detected in coral reefs, raising concerns regarding its global impact. Although they cover a small portion (<1%) of the total area of the world's oceans, coral reefs are geological and biological structures that trap MPs and disproportionately enhance their accumulation. In this review, we attempted to understand how coral reefs act as short- and long-term sinks for MPs. We describe five characteristics that lead to the enrichment of microplastics in coral reefs: 1) adhesion on reef-building corals at distinct depths; 2) ingestion by reef organisms (e.g., suspension feeders, such as sponges, ascidians, and corals), bioconcentration, and formation of short-term (i.e., years to decades) biological sinks for MPs; 3) formation of long-term (i.e., centuries) MP sinks in coral skeletons and unconsolidated subsurface sediments; 4) reduction of sediment resuspension and seafloor turbulent kinetic energy by complex marine forest architecture that reduces bottom shear stress, facilitates the retention, and deposition of small (<0.5 mm) and high-density floating MPs; and 5) diagenesis of Anthropocene sedimentary rocks containing MPs. We estimate that reef processes may remove more than 10% of floating MPs in shallow tropical waters yearly. Statistical results show that microplastic abundance for reef-building corals are higher than values found in reef sediments and especially in seawater. Moreover, pellets, films, foams and mainly fragments and fibers have been found. These field-based data support our hypothesis of sinks in the reef sediments and organisms. We highlight the role of these seascapes in the interception of MPs as traps and sinks in reef sediments, biota, and carbonate frameworks. As coral reefs are prone to MP accumulation and can become pollution hotspots, global initiatives are necessary to conserve these rich ecosystems and prevent rapidly increasing plastic pollution.


Assuntos
Antozoários , Recifes de Corais , Animais , Microplásticos , Plásticos , Ecossistema
16.
Sci Rep ; 13(1): 13469, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596337

RESUMO

In 2020, multiple lionfish (Pterois spp.) records along the equatorial Southwestern (SW) Atlantic revealed a new expansion of these potentially damaging invasive populations, which could impact over 3500 km of Brazilian coastline over the next few years, as well as unique ecosystems and marine protected areas in its path. To assess the taxonomic status, invasion route, and correlation with other centres of distribution, we investigated the genetic diversity patterns of lionfish caught in 2022 at the Amazonia, Northeastern Brazil, and Fernando de Noronha and Rocas Atoll ecoregions, using two molecular markers, the mitochondrial COI and the nuclear S7 RP1. The data indicate that all studied lionfish belong to what is generally accepted as P. volitans, and share the same genetic signature as lionfish present in the Caribbean Sea. The shared haplotypes and alleles indicate that the SW Atlantic invasion derives from an active movement of adult individuals from the Caribbean Sea into the Brazilian coast. The Amazon mesophotic reefs likely served as a stepping-stone to overcome the biogeographical barrier represented by the Amazon-Orinoco River plume. New alleles found for S7 RP1 suggest the onset of local genetic diversification, heightening the environmental risks as this bioinvasion heads towards other South Atlantic ecoregions.


Assuntos
Ecossistema , Variação Genética , Humanos , Adulto , Alelos , Oceano Atlântico , Brasil
17.
Am J Dent ; 36(4): 188-192, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37587029

RESUMO

PURPOSE: To evaluate the smoothness provided by a one-step finishing and polishing system and its maintenance after hydrothermal aging and brushing of a nanofilled resin composite. METHODS: 96 samples of the nanofilled composite Filtek Z350 XT were fabricated, which, after initial average roughness (Ra) analysis, were randomly distributed into three groups, according to the selected finishing and polishing system. The multi-step systems Sof-Lex (aluminum oxide discs) and Jiffy (bullet-shaped abrasive rubbers), and the one-step system OneGloss (bullet-shaped abrasive rubber) were used. After finishing and polishing, a new Ra measurement was performed, and then half of the samples from each group were stored in artificial saliva for 12 months, while the other half underwent aging processes associating hydrothermal cycles (10,000 cycles at 5-55°C) followed by brushing (5,500 strokes), with a mid-abrasive (Crest Cavity Protection) dentifrice slurry, simulating a 12-month period in the oral cavity. Final Ra measurements were performed, and data were analyzed by generalized linear model and Tukey's test (α= 5%). RESULTS: There was interaction between finishing and polishing system and aging (P< 0.001). The one-step abrasive rubber point provided significantly higher Ra values compared to the multi-step systems, and with the discs there was higher smoothness than with the rubber point sequence. This result was maintained after 12 months in artificial saliva, but after hydrothermal cycles followed by brushing, one-step and multi-step abrasive rubber points no longer significantly differed from each other. Only for the one-step system, hydrothermal cycles followed by brushing significantly reduced Ra. CLINICAL SIGNIFICANCE: Although hydrothermal cycles followed by brushing may have increased the smoothness of nanofilled composite finished and polished with the one-step system, only the multi-step system provided a surface within the roughness threshold to avoid biofilm retention.


Assuntos
Cárie Dentária , Borracha , Humanos , Biofilmes , Instrumentos Odontológicos , Saliva Artificial
18.
Int J Food Sci Nutr ; 74(6): 655-667, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37612883

RESUMO

Millions of dollars have been increasingly spent on plant-based diets. Considering that vitamin B12 is obtained from the consumption of animal-derived foods, new sources of vitamin B12 and methods of food fortification are being eagerly sought. Therefore, this work aims to evaluate advances in situ fermentation processes of food and beverages produced on a large scale and industrial applications for obtaining cobalamin-rich products. Bibliometric analysis was performed and revealed that several studies report a great capacity for in situ biofortification of B12 in foods, mostly on the use of propionic (PB) and lactic (LAB) bacteria. In this context, market potentials for such products, the main microorganisms, including simultaneous cultures, and their respective applications have been presented herein. Although knowledge on potential applications is still limited, field research has been increasingly conducted, thus revealing scientific and technological opportunities, both for the production and the stability of B12 found in plant-based foods.


Assuntos
Alimentos Fermentados , Vitamina B 12 , Animais , Biofortificação , Bebidas , Ração Animal
19.
J Reprod Immunol ; 159: 104134, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37634319

RESUMO

The Human Leukocyte Antigen G (HLA-G) is an immunoregulatory molecule with a critical role in pregnancy success. HLA-G alleles are associated with differential susceptibility to multiple conditions, including gestational problems, infectious diseases, and viral persistence. Of note, both herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) can impair HLA-G expression, interfering with HLA-G-associated immunoregulation. On the other hand, the impacts of HLA-G alleles on susceptibility to Herpesviridae infection is a neglected issue. Therefore, this study evaluated HLA-G allele frequencies and their associations with placental Herpesviridae infection in women from southern Brazil. Placenta samples were collected soon after delivery, and detection of viral DNA of HSV-1, HSV-2 and human cytomegalovirus (HCMV) was performed by polymerase chain reaction (PCR). A fragment of HLA-G (exons 2-4) was amplified by PCR, sequenced, and analyzed to allele determination. One hundred and seventy women had their alleles determined. Overall, 25 HLA-G alleles were found, distributed into 56 different genotypes. The most frequent alleles were G* 01:01:01 and G* 01:01:02, found in 37.9 % and 16.5 % of samples, respectively. Among the 170 women, 89 (52.4 %) tested positive for Herpesviridae DNA in the placenta, 55 (32.3 %) tested negative, 3 (1.8 %) were negative for HSV-1 and HSV-2 (with absent HCMV data), and 23 (13.5 %) were undetermined. The G* 01:01:01 allele was significantly associated with an increased risk of placental HSV-1 infection (p = 0.0151; OR=1.837; IC=1.108-3.045). This study describes new information concerning placental HLA-G alleles in women from southern Brazil and helps explain how genetic background can modify susceptibility to placental infections.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Gravidez , Feminino , Humanos , Herpesvirus Humano 1/genética , Alelos , Antígenos HLA-G/genética , Brasil/epidemiologia , Placenta , Herpesvirus Humano 2/genética , Citomegalovirus
20.
AIDS ; 37(15): 2331-2338, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37650761

RESUMO

OBJECTIVE: Combinatorial antiretroviral therapy provided improvement of HIV patients' immune function and a decrease in the incidence of non-Hodgkin lymphoma (NHL). Diffuse large B-cell lymphoma (DLBCL) is one of the most common NHL forms affecting HIV+ patients. The present study aimed to evaluate the impact of HIV infection on the prognosis of patients treated for DLBCL in a reference cancer treatment center in Brazil. METHODS: A retrospective case-control study was developed with patients followed-up at the Brazilian National Cancer Institute, in which 243 DLBCL patients (91 HIV+ and 152 HIV-) were enrolled. HIV- controls were matched to HIV+ according to date of cancer diagnosis, clinical staging, primary cancer treatment and date of birth. Sociodemographic and cancer treatment data were extracted from medical charts. Kaplan-Meier analyses were carried out to estimate survival, while univariate and multiple Cox regression analyses were used to determine factors associated with mortality. RESULTS: A total of 98 deaths were observed in a 5-year period after cancer diagnosis. A negative association of HIV infection with both overall and disease-specific survival 1 year after cancer diagnosis was observed [hazard ratio (HR) = 1.98 and 1.96, respectively]. The negative association with HIV infection with disease-specific survival remained significant for a 5-year period after cancer diagnosis (HR = 1.53). HIV viral load above 1000 copies/ml at study entry was also associated with shorter overall and cancer-specific survival. CONCLUSIONS: HIV infection negatively impacted prognosis and mortality of DLBCL patients irrespective of cancer-related clinical factors.


Assuntos
Infecções por HIV , Linfoma Difuso de Grandes Células B , Linfoma não Hodgkin , Humanos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Brasil/epidemiologia , Estudos Retrospectivos , Estudos de Casos e Controles , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Prognóstico
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