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1.
Blood Cells Mol Dis ; 106: 102838, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38413287

RESUMO

Diamond-Blackfan anemia (DBA) was the first ribosomopathy described in humans. DBA is a congenital hypoplastic anemia, characterized by macrocytic aregenerative anemia, manifesting by differentiation blockage between the BFU-e/CFU-e developmental erythroid progenitor stages. In 50 % of the DBA cases, various malformations are noted. Strikingly, for a hematological disease with a relative erythroid tropism, DBA is due to ribosomal haploinsufficiency in 24 different ribosomal protein (RP) genes. A few other genes have been described in DBA-like disorders, but they do not fit into the classical DBA phenotype (Sankaran et al., 2012; van Dooijeweert et al., 2022; Toki et al., 2018; Kim et al., 2017 [1-4]). Haploinsufficiency in a RP gene leads to defective ribosomal RNA (rRNA) maturation, which is a hallmark of DBA. However, the mechanistic understandings of the erythroid tropism defect in DBA are still to be fully defined. Erythroid defect in DBA has been recently been linked in a non-exclusive manner to a number of mechanisms that include: 1) a defect in translation, in particular for the GATA1 erythroid gene; 2) a deficit of HSP70, the GATA1 chaperone, and 3) free heme toxicity. In addition, p53 activation in response to ribosomal stress is involved in DBA pathophysiology. The DBA phenotype may thus result from the combined contributions of various actors, which may explain the heterogenous phenotypes observed in DBA patients, even within the same family.


Assuntos
Anemia de Diamond-Blackfan , Anemia Diseritropoética Congênita , Anemia Macrocítica , Humanos , Anemia de Diamond-Blackfan/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Células Precursoras Eritroides/metabolismo , Mutação
2.
Environ Toxicol ; 39(6): 3523-3536, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38465474

RESUMO

A previous study using miRNA sequencing revealed that exposure to a mixture of phthalates during pregnancy and lactation dysregulated rno-miR-184 and rno-miR-141-3p in the ventral prostate (VP) of offspring. Here, rno-miR-184 and rno-miR-141-3 expressions were obtained by RT-qPCR in the VP of F1 males as well as in F2 offspring, aiming to establish a relationship with possible oncogenic targets through in silico analyses with multigenerational approach. Additionally, some targets were measured by western blots to highlight a possible relationship between the deregulated miRNAs and some of their targets. VP samples from rats exposed to a mixture of phthalates maternally during pregnancy and lactation (GD10 to PND21-F1) and VP from offspring (F2) were examined. The phthalate mixture at both concentrations (20 µg and 200 mg/kg/day) increased the expression of both miRNAs in the F1 (PND22 and 120) and F2 (descendants of F1-treated males) prostate. Target prediction analysis revealed that both microRNAs are responsible for modulating the expression and synthesis of 40 common targets. A phthalate target association analysis and the HPA database showed an interesting relationship among these possible miRNAs modulated targets with prostate adenocarcinoma and other oncogenic processes. Western blots showed alteration in P63, P53, WNT5, and STAT3 expression, which are targeted by the miRNAs, in the VP of F1/F2 males. The data draw attention to the epigenetic modulation in the prostate of descendants exposed to phthalates and adds to one of the few currently found in the literature to point to microRNAs signature as biomarkers of exposure to plasticizers.


Assuntos
MicroRNAs , Ácidos Ftálicos , Efeitos Tardios da Exposição Pré-Natal , Neoplasias da Próstata , MicroRNAs/genética , MicroRNAs/metabolismo , Masculino , Animais , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Feminino , Ácidos Ftálicos/toxicidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/genética , Exposição Materna/efeitos adversos , Próstata/efeitos dos fármacos , Próstata/patologia , Ratos Wistar , Ratos , Simulação por Computador
3.
Reumatismo ; 76(1)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38523579

RESUMO

Spontaneous subcapsular and perirenal hemorrhage, known as Wunderlich syndrome (WS), is a rare clinical manifestation of polyarteritis nodosa (PAN). We report a case of a 48-year-old male with a history of recurrent episodes of leg muscle tenderness and dysesthesia, bilateral flank pain, painful nodular skin lesions in the lower limbs, weight loss, and difficult-to-control arterial hypertension. The abdominopelvic computed tomography angiography showed a large left perirenal hematoma, leading to the patient's admission to the intensive care unit. After the exclusion of infectious or neoplastic foci, the patient was diagnosed with PAN and started intravenous methylprednisolone pulses with a good response. Since WS is a rare initial clinical manifestation of PAN, an early diagnosis and aggressive treatment will significantly improve clinical outcomes.


Assuntos
Nefropatias , Poliarterite Nodosa , Masculino , Humanos , Pessoa de Meia-Idade , Poliarterite Nodosa/complicações , Poliarterite Nodosa/diagnóstico , Poliarterite Nodosa/terapia , Nefropatias/complicações , Nefropatias/terapia , Hemorragia/etiologia , Hematoma/complicações , Hematoma/terapia , Angiografia/efeitos adversos
4.
Reumatismo ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39315559

RESUMO

This case series aims to characterize the development of systemic lupus erythematosus (SLE) induced by anti-tumor necrosis factor α (anti-TNFα) therapy in patients with inflammatory rheumatic diseases, namely rheumatoid arthritis (RA), spondylarthritis (SpA), and psoriatic arthritis (PsA). Patients with a diagnosis of SLE induced by anti-TNFα therapy and registered on the Rheumatic Diseases Portuguese Register (Reuma.pt) who started their first anti-TNFα between 2001 and 2020 were included. Demographic, clinical, and laboratory data were obtained by consulting Reuma.pt. The diagnosis of SLE induced by anti-TNFα was considered if there was a temporal relationship between the onset of anti-TNFα therapy and manifestations (clinical and immunological) in accordance with the American College of Rheumatology/European League Against Rheumatism criteria (2019). A total of 607 patients with inflammatory rheumatic diseases and six cases of SLE induced by anti-TNF-α therapy were reviewed: two patients were affected by RA, three patients by SpA, and one by PsA. All these patients had articular and constitutional symptoms that improved after discontinuation of the anti-TNFα agent. After switching to a second anti-TNFα agent, there was no recurrence of SLE over time. The development of SLE secondary to anti-TNFα agents in inflammatory rheumatic patients is rare. In this case series, all patients had a mild disease that improved after therapy discontinuation without recurrence of the disease. SLE induced by anti-TNFα should be considered in the follow-up of RA, SpA, and PsA patients.

5.
BMC Vet Res ; 19(1): 222, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875898

RESUMO

Human and veterinary medicine have historically presented many medical areas of potential synergy and convergence. Mechanical osteoarthritis (MOA) is characterized by a gradual complex imbalance between cartilage production, loss, and derangement. Any joint instability that results in an abnormal overload of the joint surface can trigger MOA. As MOA has a prevailing mechanical aetiology, treatment effectiveness can only be accomplished if altered joint mechanics and mechanosensitive pathways are normalized and restored. Otherwise, the inflammatory cascade of osteoarthritis will be initiated, and the changes may become irreversible. The management of the disease using non-steroidal anti-inflammatory drugs, analgesics, physical therapy, diet changes, or nutraceuticals is conservative and less effective. MOA is a determinant factor for the development of hip dysplasia in both humans and dogs. Hip dysplasia is a hereditary disease with a high incidence and, therefore, of great clinical importance due to the associated discomfort and significant functional limitations. Furthermore, on account of analogous human and canine hip dysplasia disease and under the One Medicine concept, unifying veterinary and human research could improve the well-being and health of both species, increasing the acknowledgement of shared diseases. Great success has been accomplished in humans regarding preventive conservative management of hip dysplasia and following One Medicine concept, similar measures would benefit dogs. Moreover, animal models have long been used to better understand the different diseases' mechanisms. Current research in animal models was addressed and the role of rabbit models in pathophysiologic studies and of the dog as a spontaneous animal model were highlighted, denoting the inexistence of rabbit functional models to investigate therapeutic approaches in hip MOA.


Assuntos
Doenças do Cão , Luxação do Quadril , Displasia Pélvica Canina , Instabilidade Articular , Osteoartrite do Quadril , Animais , Humanos , Cães , Coelhos , Osteoartrite do Quadril/terapia , Osteoartrite do Quadril/veterinária , Luxação do Quadril/veterinária , Displasia Pélvica Canina/terapia , Instabilidade Articular/veterinária , Suplementos Nutricionais , Doenças do Cão/terapia
6.
Reumatismo ; 75(2)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37462132

RESUMO

Behçet disease (BD) is a rare systemic vasculitis of unknown etiology, primarily characterized by recurrent oral aphthous ulcers, genital ulcers, uveitis, and skin lesions. Pathergy test positivity is a nonspecific inflammatory response of the skin to trauma and supports the diagnosis. Recently, new inducers of pathergy reactions have been identified, for example, the placement of dental braces and laser hair removal. Our clinical case highlights the importance of thinking about this potential pathergy inducer in BD patients, to improve their quality of life and avoid complications.


Assuntos
Síndrome de Behçet , Antígeno HLA-B51 , Remoção de Cabelo , Lasers , Humanos , Síndrome de Behçet/complicações , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/patologia , Remoção de Cabelo/efeitos adversos , Lasers/efeitos adversos , Qualidade de Vida , Pele/patologia , Adulto
7.
Reumatismo ; 74(4)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36942981

RESUMO

Rheumatic musculoskeletal diseases or RMD [rheumatoid arthritis (RA) and spondyloarthritis (SpA)] are systemic inflammatory diseases for which there are no biomarkers capable of predicting treatments with a higher likelihood of response in naive patients. In addition, the expiration of the anti-TNF blocking drugs' patents has resulted in the availability of anti-TNF biosimilar drugs with the same efficacy and safety than originators but at significantly reduced prices. To guarantee a personalized therapeutic approach to RMD treatment, a board of rheumatologists and stakeholders from the Campania region, Italy, developed a clinically applicable arthritis therapeutic algorithm to guide rheumatologists (DATA project). The general methodology relied on a Delphi technique forecast to produce a set of statements that summarized the experts' consensus. Selected clinical scenarios were discussed in light of the available evidence, and there were two rounds of voting on the therapeutic approaches. Separate discussions were held regarding rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. The decision-making factors for each disease were clinical presentation, demographics, and comorbidities. In this paper, we describe a virtuous process between rheumatologists and healthcare system stakeholders that resulted in the development of a shared therapeutic algorithm for RMD patients naive to bDMARDs.


Assuntos
Antirreumáticos , Artrite Psoriásica , Artrite Reumatoide , Espondilartrite , Espondilite Anquilosante , Humanos , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Espondilite Anquilosante/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Artrite Psoriásica/diagnóstico , Artrite Psoriásica/tratamento farmacológico , Atenção à Saúde , Algoritmos , Antirreumáticos/uso terapêutico
8.
Mol Psychiatry ; 26(4): 1272-1285, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-31492942

RESUMO

The dopamine D2 and D3 receptors are implicated in schizophrenia and its pharmacological treatments. These receptors undergo intracellular trafficking processes that are modulated by dysbindin-1 (Dys). Indeed, Dys variants alter cognitive responses to antipsychotic drugs through D2-mediated mechanisms. However, the mechanism by which Dys might selectively interfere with the D3 receptor subtype is unknown. Here, we revealed an interaction between functional genetic variants altering Dys and D3. Specifically, both in patients with schizophrenia and in genetically modified mice, concomitant reduction in D3 and Dys functionality was associated with improved executive and working memory abilities. This D3/Dys interaction produced a D2/D3 imbalance favoring increased D2 signaling in the prefrontal cortex (PFC) but not in the striatum. No epistatic effects on the clinical positive and negative syndrome scale (PANSS) scores were evident, while only marginal effects on sensorimotor gating, locomotor functions, and social behavior were observed in mice. This genetic interaction between D3 and Dys suggests the D2/D3 imbalance in the PFC as a target for patient stratification and procognitive treatments in schizophrenia.


Assuntos
Disbindina , Receptores de Dopamina D3 , Esquizofrenia , Animais , Cognição , Humanos , Camundongos , Receptores de Dopamina D2/genética , Receptores de Dopamina D3/genética , Esquizofrenia/genética
9.
J Endocrinol Invest ; 45(3): 497-505, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34524677

RESUMO

PURPOSE: Polycystic Ovary Syndrome (PCOS) is the most frequent endocrinopathy in women of reproductive age. Machine learning (ML) is the area of artificial intelligence with a focus on predictive computing algorithms. We aimed to define the most relevant clinical and laboratory variables related to PCOS diagnosis, and to stratify patients into different phenotypic groups (clusters) using ML algorithms. METHODS: Variables from a database comparing 72 patients with PCOS and 73 healthy women were included. The BorutaShap method, followed by the Random Forest algorithm, was applied to prediction and clustering of PCOS. RESULTS: Among the 58 variables investigated, the algorithm selected in decreasing order of importance: lipid accumulation product (LAP); abdominal circumference; thrombin activatable fibrinolysis inhibitor (TAFI) levels; body mass index (BMI); C-reactive protein (CRP), high-density lipoprotein cholesterol (HDL-c), follicle-stimulating hormone (FSH) and insulin levels; HOMA-IR value; age; prolactin, 17-OH progesterone and triglycerides levels; and family history of diabetes mellitus in first-degree relative as the variables associated to PCOS diagnosis. The combined use of these variables by the algorithm showed an accuracy of 86% and area under the ROC curve of 97%. Next, PCOS patients were gathered into two clusters in the first, the patients had higher BMI, abdominal circumference, LAP and HOMA-IR index, as well as CRP and insulin levels compared to the other cluster. CONCLUSION: The developed algorithm could be applied to select more important clinical and biochemical variables related to PCOS and to classify into phenotypically different clusters. These results could guide more personalized and effective approaches to the treatment of PCOS.


Assuntos
Aprendizado de Máquina , Redes e Vias Metabólicas/genética , Síndrome do Ovário Policístico , Serviços Preventivos de Saúde , Adulto , Algoritmos , Inteligência Artificial , Variação Biológica da População , Índice de Massa Corporal , Hotspot de Doença , Feminino , Humanos , Resistência à Insulina , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Medicina de Precisão/métodos , Serviços Preventivos de Saúde/métodos , Serviços Preventivos de Saúde/tendências
10.
Lett Appl Microbiol ; 75(6): 1639-1644, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36073022

RESUMO

This study aimed to evaluate the performance of accelerated hydrogen peroxide® wipes (HPW) for decontamination of the chimpanzee adenovirus AZD1222 vaccine strain used in the production of recombinant COVID-19 vaccine in a pharmaceutical industry. Two matrices were tested on stainless-steel (SS) and low-density-polyethylene (LDP) surfaces: formulated recombinant COVID-19 vaccine (FCV) and active pharmaceutical ingredient (API). The samples were spiked, dried and the initial inoculum, possible residue effect (RE) and titre reduction after disinfection with HPW were determined. No RE was observed. The disinfection procedure with HPW resulted in complete decontamination the of AZD1222 adenovirus strain in FCV (≥7·46 and ≥7·49 log10 infectious unit [IFU] ml-1 for SS and LDP carriers respectively) and API (≥8·79 and ≥8·78 log10 IFU ml-1 for SS and LDP carriers respectively). In conclusion, virucidal activity of HPW was satisfactory against the AZD1222 adenovirus strain and can be a good option for disinfection processes of SS and LPD surfaces in pharmaceutical industry facilities during recombinant COVID-19 vaccine production. This procedure is simple and can be also applied on safety unit cabins and sampling bags made of LDP as well.


Assuntos
COVID-19 , Desinfetantes , Humanos , Peróxido de Hidrogênio/farmacologia , Desinfetantes/farmacologia , ChAdOx1 nCoV-19 , Vacinas contra COVID-19 , Adenoviridae/genética , Descontaminação/métodos , COVID-19/prevenção & controle , Desinfecção/métodos , Aço Inoxidável , Indústria Farmacêutica
11.
Lett Appl Microbiol ; 75(2): 396-400, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35599361

RESUMO

The Curtobacterium genus is a member of the family Microbacteriaceae, and Curtobacterium species are recognized as plant pathogens. The aim of this study was to investigate a dubious result of species identification for an infection located on a catheter tip of a patient with Covid-19. A strain isolated from a catheter tip sample, identified by VITEK® 2 as Cronobacter spp., was submitted to polyphasic analysis: Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) using VITEK® MS, real-time polymerase chain reaction targeting dnaG gene, and 16S rRNA full gene Sanger sequencing analysis for confirmation. The strain presented negative result using qPCR and could not identified by MALDI-TOF MS. 16S rRNA full gene Sanger sequencing analysis identified the strain as Curtobacterium spp. The Gram-variable characteristic (Gram-negative instead of Gram-positive) of the isolated strain was the responsible for the misidentification by VITEK® 2 and VITEK® MS did not identify the strain. 16S rRNA full gene sequencing analysis identified the strain as Curtobacterium genus, but other complementary techniques are necessary to identify at species level.


Assuntos
Actinomycetales , COVID-19 , Cronobacter , Actinomycetales/genética , Técnicas de Tipagem Bacteriana/métodos , Catéteres , Humanos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
12.
J Dairy Sci ; 105(10): 8328-8341, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35965116

RESUMO

This study aimed to understand the veterinary-client relationship and perspectives in organic dairy production systems. Twenty-three organic dairy producers and 12 veterinarians were interviewed using semi-structured, one-on-one interviews. Consultation with local veterinarians was typically infrequent, as there was greater reliance on other producers and organic industry professionals for advice on dairy herd health management, perhaps due to a shared focus on organic farming principles. Organic producers generally consulted local veterinarians most frequently to develop vaccine protocols, address animal health emergencies, and gain reproductive services. Common reasons organic producers cited for not regularly consulting a local veterinarian included the cost of veterinary services and a perception that local veterinarians have limited experience with organic systems and products. Some producers also expressed the idea that infrequent veterinarian usage is indicative of a healthy herd. Meanwhile, local veterinarians reported that organic dairy producers often delayed consulting them about individual cases until animal health problems were severe. Local veterinarians also identified challenges in servicing organic herds, such as the lack of standardized regulations between different organic certifiers and limited safety and efficacy data for many herd health products used by organic producers. In addition, their formal training generally did not include organic herd health strategies. Organic dairy clients were typically a small fraction of the overall workload for local veterinarians, which precluded their ability to accumulate experience. In contrast, a handful of specialized veterinarians in the organic milk processing industry work more frequently with organic producers and have published most of the available resource materials on organic dairy herd health. Veterinary-client partnerships could be improved through more open communication and discussion of the challenges identified in this study and through participatory research and outreach engagement that includes local veterinarians, organic certifiers, organic industry veterinarians, and producers.


Assuntos
Médicos Veterinários , Animais , Indústria de Laticínios/métodos , Humanos , Leite , Agricultura Orgânica , Encaminhamento e Consulta
13.
Reumatismo ; 74(3)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36580064

RESUMO

The primary objectives of the study were to evaluate the efficacy and safety of tofacitinib and baricitinib up to 24 months of follow-up in patients with rheumatoid arthritis (RA) treated in Southern Italy. Patients' data, activity index, and clinimetric scores were collected at baseline (T0), six (T6), twelve (T12), and twenty-four (T24) months following treatment initiation. At six, twelve, and twenty-four months, adverse events and treatment cessation were also recorded. Sixty-eight patients (mean age: 62.2±10.9 years; mean RA duration: 15±9.6 years) were enrolled over a period of 12 weeks. At baseline, twenty-four patients (35.3%) were treated with tofacitinib, and forty-four patients (64.7%) were treated with baricitinib. The baseline mean disease activity was moderate as measured by DAS28- ESR (5.0±1.0), DAS 28 CRP (4.69±0.94), and SDAI (26.87±10.73) score. Before beginning JAKinhibs therapy, thirty-two patients (61.8%) were taking bDMARDs, while the remaining thirty-six (38.2%) were bDMARDs-naïve. The 24-month retention rate for JAKinhibs was 91.1%. Six months after beginning treatment with JAKinhibs, a statistically significant improvement was observed in all evaluated activity indices and clinimetric scores. Improvement was confirmed during the 12- and 24-month follow-up evaluations. The positive correlation between baseline-T6 SDAI delta and discontinuation of JAKinhibs (p=0.02) suggests that RA worsening in the first six months may be a predictor of therapy withdrawal. Patients with RA responded favorably to tofacitinib and baricitinib in this prospective, real-world study from a single center in Southern Italy. Efficacy was observed despite an underlying persistent and treatment-resistant disease.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Antirreumáticos/efeitos adversos , Pirróis/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Resultado do Tratamento
14.
Eur J Prosthodont Restor Dent ; 30(4): 267-275, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-35438266

RESUMO

OBJECTIVES: The objective of this systematic review was to compare the longevity of direct amalgam and composite resin restorations, in posterior teeth, through clinical, prospective or retrospective studies, with at least 5 years of follow-up. MATERIALS AND METHODS: Studies published in the last 15 years (from 2006 to 2021) were collected using the PubMed and Medline databases. RESULTS: The search strategy associated with the established inclusion and exclusion criteria resulted in a total of 17 articles. Factors related to failures in the performance of restorations were analyzed together with the clinical performance results of each material over the years of study, according to the methodology of each article. CONCLUSIONS: Regardless of the restorative material, the successful results over more than 5 years are due much more to the correct application of the technique, the operator's skill/knowledge and factors related to the patient, such as the type of tooth, number of faces involved in the restoration and oral hygiene.


Assuntos
Resinas Compostas , Materiais Dentários , Humanos , Estudos Prospectivos , Estudos Retrospectivos
15.
Phys Rev Lett ; 126(9): 091101, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750144

RESUMO

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}≲10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}≲(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{ϕ}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}≲0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.

16.
Eur Phys J E Soft Matter ; 44(9): 109, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34463819

RESUMO

This work reports an analysis of the dielectric properties of reduced graphene oxide mixed into epoxy resin, diglycidyl ether of bisphenol A, in the frequency range 10[Formula: see text]-10[Formula: see text] Hz and over the temperature range of 300-400 K, using impedance spectroscopy. For this study, a series of samples were prepared with various filler contents. Using the electric modulus formalism, it has been found that these composites exhibit below and above the percolation threshold [Formula: see text] a critical behavior of the dielectric relaxation phenomenon due to the single [Formula: see text]-relaxation, which is associated with the glass-rubbery transition of the epoxy matrix above the glass transition temperature. The Cole-Cole model of dielectric relaxation was used for modeling the relaxation processes from which we extract the relaxation parameters. The obtained relaxation parameters suggest a behavior close to single relaxation time.

17.
J Appl Microbiol ; 131(1): 169-181, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33306232

RESUMO

AIM: The current study was conducted to determine the antimicrobial resistance profile and genetic relatedness of Aeromonas sp. isolated from healthcare and urban effluents, wastewater treatment plant (WWTP) and river water. METHODS AND RESULTS: We detected the presence of genes conferring resistance to ß-lactam, quinolone and aminoglycoside. Multilocus sequence typing was carried out to differentiate the strains, and multilocus phylogenetic analysis was used to identify the species. A total of 28 cefotaxime-resistant Aeromonas sp. strains were identified, harbouring uncommon Guiana-extended-spectrum (GES)-type ß-lactamases (GES-1, GES-5, GES-7 and GES-16). Multidrug-resistant Aeromonas sp. were found in hospital wastewater, WWTP and sanitary effluent, and A. caviae was identified as the most prevalent species (85·7%). CONCLUSION: The release of untreated healthcare effluents, presence of antimicrobials in the environment, in addition to multidrug-resistant Aeromonas sp., are all potential factors for the spread of resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: We identified a vast repertoire of antimicrobial resistance genes (ARG) in Aeromonas sp. from diverse aquatic ecosystems, including those that encode enzymes degrading broad-spectrum antimicrobials widely used to treat healthcare-associated infections. Hospital and sanitary effluents serve as potential sources of bacteria harbouring ARG and are a threat to public health.


Assuntos
Aeromonas/efeitos dos fármacos , Aeromonas/genética , Antibacterianos/farmacologia , Águas Residuárias/microbiologia , Aeromonas/classificação , Aminoglicosídeos/farmacologia , Brasil , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Ecossistema , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Quinolonas/farmacologia , beta-Lactamases/genética , beta-Lactamas/farmacologia
18.
Nature ; 519(7543): 344-8, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25788097

RESUMO

Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.


Assuntos
Dióxido de Carbono/análise , Sequestro de Carbono , Floresta Úmida , Atmosfera/química , Biomassa , Brasil , Carbono/análise , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Caules de Planta/metabolismo , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Clima Tropical , Madeira/análise
19.
J Dairy Sci ; 104(5): 5867-5880, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33516550

RESUMO

Organic dairy producers have distinct perspectives, approaches, challenges, and experiences when managing herd health, but little research has been conducted to develop a deeper understanding of producer decision-making related to disease-prevention and treatment strategies. We used 23 semi-structured interviews with organic dairy producers to better understand their perceived herd health challenges and overall disease-prevention strategies; decision-making and attitudes related to vaccination; and approaches to the treatment of infectious diseases using alternative or conventional antimicrobial therapies. Organic dairy producers reported improvements in overall animal health after they transitioned from a conventional to an organic system. Outdoor access, a balanced forage-based diet, and animal and environmental cleanliness were reported as the predominant disease-prevention measures. Over half of producers vaccinated their animals, and almost all preferred to use vaccines sparingly. Among producers who did not use vaccines, reasons cited were low perceived risk for infectious disease and minor vaccine safety concerns, yet many were not opposed to using vaccines in the future. Non-antimicrobial therapies were viewed as alternative effective treatment strategies for most common infectious diseases. Producers used antimicrobials very rarely and generally reserved them for severe cases when alternative treatments failed. Because US organic standards prohibit selling milk from cows that have ever been treated with antimicrobials, producers described the decision to use antimicrobials as extremely challenging and involved balancing considerations of economics, convenience, and animal welfare. This research fosters a better understanding of organic dairy producers' disease-prevention and treatment strategies and could be used by veterinarians and other animal health specialists to facilitate services for organic clients.


Assuntos
Doenças dos Bovinos , Médicos Veterinários , Bem-Estar do Animal , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios , Feminino , Humanos , Leite
20.
Phys Rev Lett ; 124(10): 101102, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216401

RESUMO

In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.

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