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1.
An Acad Bras Cienc ; 96(4): e20230952, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39319848

RESUMO

Triatominae are recognized as vectors of Trypanosoma cruzi, a protozoan which is the etiological agent of Chagas disease. A specimen of Triatoma delpontei was found at Porto Murtinho in Mato Grosso do Sul State, Brazil. This is the first report of the occurrence of T. delpontei to the state of Mato Grosso do Sul, Brazil. With the present finding, the total number of triatomines recorded in Mato do Grosso do Sul reaches 17 species, while T. delpontei, previously recorded only from Rio Grande do Sul, is now recorded to a second Brazilian state. Based on the information available in the literature, a meticulous and organized compilation has been crafted, highlighting the cytogenetics differentiations of the species occurring in this state. This work emphasizes the importance of continuous research and surveillance on Triatominae, recognized as vectors of T. cruzi.


Assuntos
Doença de Chagas , Insetos Vetores , Triatoma , Animais , Brasil , Triatoma/classificação , Insetos Vetores/classificação , Doença de Chagas/transmissão , Trypanosoma cruzi
2.
Sci Total Environ ; 950: 175029, 2024 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-39117211

RESUMO

The elemental composition and carbon and nitrogen stable isotopes of sedimentary organic matter (OM) are vital geochemical tools for understanding environments, physical and biogeochemical processes, and even paleoclimatic conditions on Earth. Given that the Antarctic Peninsula region is one of the few areas that remain relatively preserved compared to many other regions on Earth, sensitive to climate change, and yet remains the least explored continent, this study aimed to characterise the elemental (total organic carbon and total nitrogen) and isotopic (δ13C and δ15N) composition of marine sediments from various regions of Admiralty Bay, King George Island, Antarctica. This was done to assess potential sources of OM. The sampling included: (i) 17 surface sediment samples collected across the bay in January 2020; (ii) surface sediment samples collected during the 2009-2019 period at three specific inlets of Admiralty Bay; and (iii) three sediment cores collected from each inlet in 2007-2008. TOC and TN varied from 0.09 to 0.99 % and 0.02 to 0.18 %, respectively. The δ13C values ranged from -25.9 to -18.4 ‰, while the δ15N values varied from -12.4 to 22.7 ‰. The C/N ratio values were from 2.5 to 19.3. OM in sediments from Ezcurra Inlet primarily originates from terrestrial plants prevalent in Antarctica, such as mosses and lichens, alongside aquatic plants like algae and phyto- and zooplankton. Similarly, Mackelar Inlet is characterised by substantial contributions from these abovementioned sources. In contrast, Martel Inlet exhibits diverse sources, predominantly influenced by various marine mammals and seabirds and their excrements, in addition to the signals from mosses and lichens. Recent sediments sampled post-2008 in Martel Inlet show a decreased contribution from animal sources, with mosses and lichens emerging as the predominant contributors, corroborating patterns observed in the other inlets. Our findings suggest that climate change is expanding ice-free areas, promoting the growth of terrestrial vegetation, and altering the composition of sedimentary OM in Admiralty Bay, indicating changes over the studied time scale.

3.
Sci Total Environ ; 951: 175551, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151623

RESUMO

Despite being one of the most remote areas on the planet, the Antarctic continent is subject to anthropogenic influences. The presence of various groups of contaminants, including persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), has been documented in the region over the past decades. However, a significant knowledge gap remains regarding the detection of new pollutants, such as emerging contaminants (ECs), in Antarctic coastal environments. This study analyzed the occurrence and levels of selected POPs, PAHs, ECs in surface sediments from Admiralty Bay, Antarctica Peninsula. Non-target screening was employed to identify potential novel contaminants in the region. Samples (n = 17) were extracted using an accelerated solvent extraction (ASE) system and instrumental analyses were performed using gas chromatography coupled to a triple-quadrupole mass spectrometer (GC/MS-MS). Regarding regulated contaminants, concentrations of Σ5PCBs ranged from

4.
Chemosphere ; 364: 143193, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39197685

RESUMO

The Iguaçu River basin, known for its rich endemic ichthyofauna, faces a significant threat from chemical pollution. The Jordão River, a major tributary, drains extensive agricultural and livestock areas and receives poorly treated domestic and industrial effluents before joining the Iguaçu River. This study investigated the pollution and toxic effects of water samples from the Iguaçu upstream (UI), Jordão (JR), and their confluence (DI) on Steindachneridion melanodermatum embryos and larvae. Chemical analyses of the water samples revealed that most contaminants were present at levels below detection limits or within the limits established by Brazilian legislation. However, cadmium in UI, aluminum in JR, and lead in DI exceeded the legal limits. Exposure up to 96 h post-fertilization revealed higher mortality and deformity rates in individuals exposed to water samples from UI and JR, despite JR having fewer detected pollutants. JR and DI samples induced increased superoxide dismutase activity, indicating activation of the antioxidant defense system due to xenobiotic exposure. Overall, the integrated biomarker response indexes showed that individuals exposed to JR water displayed the most significant variations in their responses compared to the control treatment, suggesting a higher level of contamination and toxicity. Although a direct link between water quality and toxicity in the Jordão and Iguaçu Rivers was inconclusive, the results confirmed pollution and risks to local wildlife. The study highlighted the harmful effects of pollutants, even at low concentrations. These findings underscore the need for conservation measures to safeguard endemic and endangered species in the Iguaçu River basin. Understanding pollutant effects on native species is crucial for effective mitigation strategies and ecological health preservation.


Assuntos
Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Brasil , Animais , Rios/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Larva/efeitos dos fármacos , Cladocera/efeitos dos fármacos
5.
bioRxiv ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38585864

RESUMO

Several neuronal populations in the brain transmit both the excitatory and inhibitory neurotransmitters, glutamate, and GABA, to downstream neurons. However, it remains largely unknown whether these opposing neurotransmitters are co-released onto the same postsynaptic neuron simultaneously or are independently transmitted at different time and locations (called co-transmission). Here, using whole-cell patch-clamp recording on acute mouse brain slices, we observed biphasic miniature postsynaptic currents, i.e., minis with time-locked excitatory and inhibitory currents, in striatal spiny projection neurons (SPNs). This observation cannot be explained by accidental coincidence of monophasic miniature excitatory and inhibitory postsynaptic currents (mEPSCs and mIPSCs, respectively), arguing for the co-release of glutamate and GABA. Interestingly, these biphasic minis could either be an mEPSC leading an mIPSC or vice versa. Although dopaminergic axons release both glutamate and GABA in the striatum, deletion of dopamine neurons did not eliminate biphasic minis, indicating that the co-release originates from another neuronal type. Importantly, we found that both types of biphasic minis were detected in other neuronal subtypes in the striatum as well as in nine out of ten additionally tested brain regions. Our results suggest that co-release of glutamate and GABA is a prevalent mode of neurotransmission in the brain.

6.
Int J Parasitol Drugs Drug Resist ; 24: 100527, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447333

RESUMO

Haemonchus contortus and Trichostrongylus colubriformis are the most important gastrointestinal nematodes causing serious losses in sheep production of tropical and subtropical regions. Prophylaxis of gastrointestinal nematode infections is based on anthelmintics use, but their frequent administration selects multiple-resistant parasites. To evaluate how the situation has changed over the last decades, the anthelmintic resistance status of gastrointestinal nematodes in sheep flocks was assessed in the current study and compared to previous surveys. In each one of the 15 flocks evaluated, animals (n ≥ 7) were allocated into at least five groups and treated as follows: 1) untreated control; 2) albendazole; 3) levamisole; 4) ivermectin; and 5) monepantel. If more animals were available, two additional groups were included: 6) closantel, and 7) moxidectin. The faecal egg count reduction test (FECRT) was carried out to evaluate the pre- and post-treatment using the SHINY tool. Haemonchus spp. was the most prevalent nematode from faecal cultures. The mean efficacy of albendazole was 40%. Only in two farms, levamisole presented a relatively high percentage of reduction in the FECRT about 90%, while ivermectin and moxidectin presented the worst mean efficacy of 34% and 21% among all farms, respectively. Like other anthelmintics, closantel demonstrated low efficacy (63%) across all farms evaluated. Monepantel presented an overall mean efficacy of 79%, but it was the only anthelmintic that presented efficacy ≥95%, in five farms. The results revealed that gastrointestinal nematodes with multiple anthelmintic resistance were prevalent in all 15 sheep herds. The research suggests that nematodes are becoming more and more resistant to various anthelmintic compounds, which has made the problem worse. This circumstance highlights the necessity to put into practice sustainable and long-lasting methods to prevent gastrointestinal nematode infections in sheep husbandry.


Assuntos
Aminoacetonitrila/análogos & derivados , Anti-Helmínticos , Haemonchus , Macrolídeos , Nematoides , Infecções por Nematoides , Salicilanilidas , Doenças dos Ovinos , Animais , Ovinos , Levamisol/farmacologia , Levamisol/uso terapêutico , Ivermectina/uso terapêutico , Albendazol/uso terapêutico , Brasil/epidemiologia , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/veterinária , Fezes/parasitologia , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Contagem de Ovos de Parasitas/veterinária , Resistência a Medicamentos
7.
Mar Pollut Bull ; 195: 115499, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37742512

RESUMO

Sedimentary aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were studied in subtropical estuaries with distinct degrees of legal protection, located in the Southwestern Atlantic Ocean, São Paulo State, Brazil. A multivariate approach was adopted, using the Hierarchical cluster analysis followed by the Principal Matrix Factorization analysis to support the hydrocarbons sources findings using diagnostic ratios. In general, the sites with the highest values of hydrocarbons were in the vicinity of well-urbanized cities, where sewage discharge, harbor and industrial activities take place. Pyrolitic PAHs were the predominant source of PAHs in the sites. The region can be considered not highly contaminated by hydrocarbons; however, specific sites under local anthropogenic impact from sewage and/or urban drainage, presented relatively high hydrocarbons levels. These findings highlight the importance of sources identification as reliable approach to be included in the management plan of protected areas under the inputs of several vectors of contamination.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Brasil , Estuários , Esgotos/análise , Sedimentos Geológicos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Hidrocarbonetos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
8.
Nature ; 621(7980): 716-722, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37758891

RESUMO

Einstein's general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Dirac's theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7-10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive 'antigravity' is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP.

9.
An Acad Bras Cienc ; 95(suppl 3): e20211520, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37585980

RESUMO

The determination of dissolved iron concentrations and speciation was conducted for the first time in surface seawater coastline samples collected during the austral summer of 2020 in Admiralty Bay, King George Island, Antarctica. The technique of competitive ligand exchange/adsorptive cathodic stripping voltammetry with 2,3-dihydroxynaphthalene as the competing ligand was evaluated, showing a sensitivity between 14.25 and 21.05 nA nmol L-1 min-1, with an LOD of 14 pmol L-1 and a mean blank contribution of 0.248 nmol L-1. Physicochemical parameters such as pH (7.85 ± 0.2), salinity (32.7 ± 0.8) and dissolved oxygen (51.3 ± 26.6%) were compatible with those of the literature; however, the average temperature (4.2 ± 0.8 °C) was higher, possibly as a reflection of global warming. The dissolved iron mean value was 18.9 ± 6.1 nmol L-1, with a total ligand concentration of 23.6 ± 12.2 nmol L-1 and a conditional stability complex constant of 12.2 ± 0.2, indicating humic substances as possible ligands. On average, the calculated free iron concentrations were 0.7 ± 0.3 pmol L-1. Relatively high concentrations of iron indicate a possible local source of Fe, likely predominantly from upwelling sediments and secondarily from ice-melting waters, which does not limit the growth of the phytoplankton.


Assuntos
Baías , Ferro , Regiões Antárticas , Ligantes , Monitoramento Ambiental/métodos
10.
Sci Rep ; 13(1): 4621, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944685

RESUMO

The cosmopolitan distribution of humpback whales (Megaptera novaeangliae) is largely driven by migrations between winter low-latitude breeding grounds and summer high-latitude feeding grounds. Southern Hemisphere humpback whales faced intensive exploitation during the whaling eras and recently show evidence of population recovery. Gene flow and shared song indicate overlap between the western (A) and eastern (B1, B2) Breeding Stocks in the South Atlantic and Indian Oceans (C1). Here, we investigated photo-identification evidence of population interchange using images of individuals photographed during boat-based tourism and research in Brazil and South Africa from 1989 to 2022. Fluke images were uploaded to Happywhale, a global digital database for marine mammal identification. Six whales were recaptured between countries from 2002 to 2021 with resighting intervals ranging from 0.76 to 12.92 years. Four whales originally photographed off Abrolhos Bank, Brazil were photographed off the Western Cape, South Africa (feeding grounds for B2). Two whales originally photographed off the Western Cape were photographed off Brazil, one traveling to the Eastern Cape in the Southwestern Indian Ocean (a migration corridor for C1) before migrating westward to Brazil. These findings photographically confirm interchange of humpback whales across the South Atlantic and Indian Oceans and the importance of international collaboration to understand population boundaries.


Assuntos
Jubarte , Animais , Oceano Atlântico , Estações do Ano , Oceano Índico , Brasil
11.
Mar Pollut Bull ; 188: 114678, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36764149

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) were analysed in the sediments of one of the most well-preserved estuaries in South Brazil, the Paranaguá Estuarine System (PES), using several source apportionment tools. The ∑PAH ranged from < DL to 125.6 ng g-1 dw (dry weight) (average 29.9 ± 26.1 ng g-1 dw), and the lowest levels detected were similar to those found in other protected areas of the world. In general, the PAH concentrations indicated excellent environmental quality for the entire estuary. Principal component analysis indicated that fine sediments and total organic carbon were the main factors controlling PAH concentrations in the PES. Multiple PAH sources were identified in the study area; biomass burning and fossil fuel combustion predominated but considerable amounts of petrogenic residues were also observed. We identified evidence of a contribution from an adjacent watershed resulting from the construction of interconnections between large rivers and from years of intense deforestation in the local Atlantic Forest.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Estuários , Hidrocarbonetos Policíclicos Aromáticos/análise , Efeitos Antropogênicos , Sedimentos Geológicos/química , Monitoramento Ambiental/métodos , Rios/química , China
12.
Vet Res Commun ; 47(3): 1207-1216, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36595201

RESUMO

Targeted selective treatment (TST) is an alternative method to reduce the use of anthelmintics and delay the development of resistant nematode populations. However, there is limited information on the actual effects of this type of treatment on livestock productivity. The objective of this study was to evaluate the production performance of Santa Ines (hair) and Ile de France (wool) lambs naturally infected with gastrointestinal nematodes (GIN) under TST based on packed cell volume (PCV) versus suppressive anthelmintic treatments. Thirty-eight lambs were divided into two treatment groups: Suppressive treatment, animals were drenched with monepantel every two weeks and TST, animals were treated with the same anthelmintic when they presented PCV ≤ 20%. Feces, blood, and weight were measured weekly to determine eggs per gram of feces, PCV, total plasma protein, and weight gain. After animals were slaughtered, carcasses were weighed to determine carcass yield. In the TST group, substantial productive losses of approximately 21.3% in the wool and 25.9% in the hair lambs were observed in body weight compared to their counterparts. Significant differences in hematological variables occurred over the experimental period, especially in the wool lambs under TST. Favorable environmental conditions enabled infective larvae to survive and thrive on pasture. Haemonchus contortus and intestinal nematodes were the most common parasites found in the Ile de France lambs and the Santa Ines lambs, respectively. Although TST prevented mortality, it did not prevent production losses. Both breeds showed a significant drop in production due to GIN parasitism.


Assuntos
Anti-Helmínticos , Hemoncose , Haemonchus , Nematoides , Doenças dos Ovinos , Ovinos , Animais , , Brasil , Carneiro Doméstico , Anti-Helmínticos/uso terapêutico , Fezes/parasitologia , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Contagem de Ovos de Parasitas/veterinária , Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Hemoncose/parasitologia
13.
Rev Cient Odontol (Lima) ; 11(1): e141, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38288316

RESUMO

Abstract: To compare the diagnostic accuracy of digital radiography (DR) and cone beam computed tomography (CBCT) in the detection of peri-implant bone defects. Materials and methods: Implants were placed in 5 fresh bovine ribs (3 without peri-implant bone defects, 12 with 1.4mm peri-implant bone defects) and images were taken using (i) portable x-ray system (DEXCOWIN 3000), (ii) intraoral x-ray sensor (SENSOR H1/SENSOR H2), (iii) volume-limited HSCT with 3D Accuitomo 80 (CASTELLINI). Images of each were randomly presented to 10 examiners. Confidence in the diagnosis of the presence or absence of a peri-implant radiolucency was recorded on a scale of bone defect definitely absent, doubts about the defect if absent or present, defect definitely present. Analyzes was performed using a kappa test. Results: There has been a coincidence between the direct digital radiography and the cone beam computed tomography in piece A of 83.3%, in piece B of 100% and in piece C of 88%, giving an average total coincidence 90.43%.Conclusion: Direct digital radiography provided the same results as cone beam computed tomography in the detection of peri-implant bone defects at an early stage. Digital radiographs are a reliable and valid method and perform significantly better than cone beam computed tomography for detecting peri-implant bone defects at an early stage.

15.
An Acad Bras Cienc ; 94(4): e20210286, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36449901

RESUMO

A trial was conducted to evaluate phosphorus release capacity in different commercial phytases throught performance and bone characteristics of broilers. A total of 2,400-day-old male Cobb 500® chicks were assigned in a completely randomized design with 12 dietary treatments ((1 to 5: with increasing levels of non-phytate phosphorus (NPP) (0.20; 0.25; 0.30; 0.35 and 0.40%) without phytase); and 6 to 12: with 0.20% supplemented with different commercial phytases), 8 replicates and 25 birds per pen. There was a linear increase (P<0.05) in the feed intake and body weight gain and a linear improvement (P<0.05) in the feed conversion ratio of broilers fed increasing NPP. The tested phytases did not release similar amounts of phytic phosphorus. Based on body weight gain response, 500 FTU/kg of diet releases a minimum and maximum of 0.074 to 0.152%, 0.062 to 0.157 and 0.059 to 0.169% of PP among the studied phytases in the periods from 1 to 21, 1 to 35 and 1 to 42 days, respectively. In conclusion, the commercial phytases released different concentrations of phytate phosphorus from the diets. Thus, is necessary to have a better method to evaluate phytase activity in order to avoid subnormal levels of available P in diets.


Assuntos
6-Fitase , Animais , Masculino , Galinhas , Dieta/veterinária , Fósforo , Ácido Fítico , Aumento de Peso
16.
Nat Methods ; 19(11): 1461-1471, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36303019

RESUMO

Cyclic adenosine monophosphate (cAMP) signaling integrates information from diverse G-protein-coupled receptors, such as neuromodulator receptors, to regulate pivotal biological processes in a cellular-specific and subcellular-specific manner. However, in vivo cellular-resolution imaging of cAMP dynamics remains challenging. Here, we screen existing genetically encoded cAMP sensors and further develop the best performer to derive three improved variants, called cAMPFIREs. Compared with their parental sensor, these sensors exhibit up to 10-fold increased sensitivity to cAMP and a cytosolic distribution. cAMPFIREs are compatible with both ratiometric and fluorescence lifetime imaging and can detect cAMP dynamics elicited by norepinephrine at physiologically relevant, nanomolar concentrations. Imaging of cAMPFIREs in awake mice reveals tonic levels of cAMP in cortical neurons that are associated with wakefulness, modulated by opioids, and differentially regulated across subcellular compartments. Furthermore, enforced locomotion elicits neuron-specific, bidirectional cAMP dynamics. cAMPFIREs also function in Drosophila. Overall, cAMPFIREs may have broad applicability for studying intracellular signaling in vivo.


Assuntos
Técnicas Biossensoriais , Animais , Camundongos , Técnicas Biossensoriais/métodos , AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Neurônios/metabolismo , Transdução de Sinais , Drosophila/metabolismo
18.
Cancers (Basel) ; 14(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36010850

RESUMO

We conducted a systematic review and meta-analysis of the diagnostic performance of current deep learning algorithms for the diagnosis of lung cancer. We searched major databases up to June 2022 to include studies that used artificial intelligence to diagnose lung cancer, using the histopathological analysis of true positive cases as a reference. The quality of the included studies was assessed independently by two authors based on the revised Quality Assessment of Diagnostic Accuracy Studies. Six studies were included in the analysis. The pooled sensitivity and specificity were 0.93 (95% CI 0.85−0.98) and 0.68 (95% CI 0.49−0.84), respectively. Despite the significantly high heterogeneity for sensitivity (I2 = 94%, p < 0.01) and specificity (I2 = 99%, p < 0.01), most of it was attributed to the threshold effect. The pooled SROC curve with a bivariate approach yielded an area under the curve (AUC) of 0.90 (95% CI 0.86 to 0.92). The DOR for the studies was 26.7 (95% CI 19.7−36.2) and heterogeneity was 3% (p = 0.40). In this systematic review and meta-analysis, we found that when using the summary point from the SROC, the pooled sensitivity and specificity of DL algorithms for the diagnosis of lung cancer were 93% and 68%, respectively.

19.
Clin Transl Allergy ; 12(6): e12153, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35734271

RESUMO

Background: Obesity has often been associated with severe allergic asthma (AA). Here, we analyzed the frequency of different circulating CD4+T-cell subsets from lean, overweight and obese AA patients. Methods: Mononuclear cells from peripheral blood were obtained from 60 AA patients and the frequency of different CD4+T-cell subsets and type 1 regulatory B cells (Br1) was determined by cytometry. The effect of obese-related leptin dose on cytokine production and Treg cell function in AA-derived CD4+ T cell cultures was evaluated by ELISA and 3H thymidine uptake, respectively. Leptin levels were quantified in the plasma by ELISA. According to the BMI, patients were stratified as lean, overweight and obese. Results: AA severity, mainly among obese patients, was associated with an expansion of hybrid Th2/Th17 and Th17-like cells rather than classic Th2-like cells. On the other hand, the frequencies of Th1-like, Br1 cells and regulatory CD4+ T-cell subsets were lower in patients with severe AA. While percentages of the hybrid Th2/Th17 phenotype and Th17-like cells positively correlated with leptin levels, the frequencies of regulatory CD4+ T-cell subsets and Br1 cells negatively correlated with this adipokine. Interestingly, the obesity-related leptin dose not only elevated Th2 and Th17 cytokine levels, but also directly reduced the Treg function in CD4+ T cell cultures from lean AA patients. Conclusion: In summary, our results indicated that obesity might increase AA severity by favoring the expansion of Th17-like and Th2/Th17 cells and decreasing regulatory CD4+T cell subsets, being adverse effects probably mediated by leptin overproduction.

20.
Gac Med Mex ; 158(2): 78-82, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35763821

RESUMO

INTRODUCTION: The study of anti-SARS-CoV-2 IgG antibodies allows asymptomatic individuals with COVID-19 to be identified, and post-infection and post-vaccination immunity status to be evaluated. OBJECTIVE: To know the behavior of anti-SARS-CoV-2 IgG antibodies before and after vaccination in workers of a cancer center. METHODS: Prior to the application of the vaccine, the presence of anti-SARS-CoV-2 IgG antibodies (n = 171) was analyzed by evaluating anti-N IgG antibodies; post-vaccination, after receiving the second dose, anti-S IgG antibodies were evaluated (n = 60). RESULTS: Prior to vaccination, IgG antibodies were present in 18.71% of participants; they were detected in 65.22% of those with prior history of COVID-19 diagnosis and in 11.49% of those without it. The positions with the highest prevalence were nurses (28.26%), paramedics (27.59%) and administrative workers (27.78%), p < 0.01. Anosmia, ageusia and chest tightness were associated with the presence of IgG (p < 0.05). Post-vaccination, all participants developed IgG antibodies; people with a previous COVID-19 diagnosis had higher titers: 10,277 vs. 6,819 AU/mL, p < 0.001. CONCLUSIONS: The study of anti-SARS-CoV-2 IgG antibodies allowed asymptomatic health workers to be identified. A high percentage of participants with prior COVID-19 diagnosis had antibodies. All participants developed IgG antibodies after vaccination, with higher titers being identified in those with previous infection.


INTRODUCCIÓN: El estudio de anticuerpos IgG anti-SARS-CoV-2 permite identificar individuos asintomáticos con COVID-19 y evaluar la inmunidad posinfección y posvacunación. OBJETIVO: Conocer el comportamiento de los anticuerpos IgG anti-SARS-CoV-2 pre y posvacunación en trabajadores de un centro oncológico. MÉTODOS: Antes de aplicar la vacuna se analizaron los anticuerpos IgG anti-SARS-CoV-2 (n = 171) con la evaluación de IgG anti-N; después de la segunda dosis se evaluó IgG anti-S (n = 60). RESULTADOS: Prevacunación, los anticuerpos IgG estaban presentes en 18.71 % de los participantes; se detectaron en 65.22 % de aquellos con antecedente de diagnóstico de COVID-19 y en 11.49 % de aquellos sin antecedentes. Los profesiones con mayor prevalencia fueron enfermeros (28.26 %), paramédicos (27.59 %) y administrativos (27.78 %), p < 0.01. La anosmia, ageusia y opresión en el pecho se asociaron a la presencia de IgG (p < 0.05). Posvacunación, todos los participantes desarrollaron IgG; las personas con diagnóstico previo de COVID-19 presentaron mayores títulos: 10 277 versus 6819 UA/mL, p < 0.001. CONCLUSIONES: El estudio de anticuerpos IgG anti-SARS-CoV-2 permitió identificar a trabajadores de salud asintomáticos. Un alto porcentaje de los participantes con diagnóstico previo de COVID-19 presentó anticuerpos. Todos los participantes desarrollaron anticuerpos IgG posvacunación; las personas con infección previa presentaron una cuantificación más alta de títulos.


Assuntos
COVID-19 , Neoplasias , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Anticorpos Antivirais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Teste para COVID-19 , Humanos , Imunoglobulina G , Vacinação
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