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1.
Int J Tuberc Lung Dis ; 28(5): 237-242, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38659139

RESUMO

OBJECTIVETo describe the characteristics of people indicated for directly observed treatment (DOT) in Spain, and the factors associated with unsuccessful treatment.METHODSThis was a multicentre observational study based on a prospective follow-up of patients over 18 years old diagnosed with TB between 2006 and 2019 from the registry of the Programa Integrado de Investigación en Tuberculosis (PII-TB). Sociodemographic and clinical variables were collected. Adjusted odds ratios (aORs) were calculated for the indication of DOT and for having an unsuccessful treatment.RESULTSA total of 7,883 patients were included. The indication of DOT was associated with being homeless (aOR 5.93, 95% CI 3.03-11.59), inactivity status (aOR 2.55, 95% CI 2.02-3.23), alcohol consumption (aOR 1.94, 95% CI 1.51-2.48), parenteral drug use (aOR 1.77, 95% CI 1.06-2.95) and HIV diagnosis (aOR 1.96, 95% CI 1.16-3.29). Unsuccessful treatment was associated with having an HIV diagnosis (aPR 2.31, 95% CI 1.31-4.08), having a worse clinical and radiological evolution (clinical progression: APR 15.59, 95% CI 8.21-29.60; radiological progression: aPR 12.84, 95% CI 6.46-25.52), need for hospitalisation (aPR 1.73, 95% CI 1.10-2.73), unsatisfactory tolerability (aPR 2.82, 95% CI 1.49-5.29), the existence of difficulties in understanding the prescribed treatment (aPR 1.92, 95% CI 1.21-3.06), as well as worse treatment satisfaction (aPR 7.27, 95% CI 4.32-12.24).CONCLUSIONThe prioritisation of vulnerable populations is a key aspect to carry out the new Global Plan to End TB 2023-2030. In these groups DOT indication should be increased to ensure adherence and patient follow-up and outcomes..


Assuntos
Terapia Diretamente Observada , Encaminhamento e Consulta , Humanos , Masculino , Feminino , Espanha , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Encaminhamento e Consulta/estatística & dados numéricos , Antituberculosos/administração & dosagem , Tuberculose/tratamento farmacológico , Falha de Tratamento , Pessoas Mal Alojadas/estatística & dados numéricos , Seguimentos , Fatores de Risco , Adulto Jovem , Idoso , Infecções por HIV/tratamento farmacológico
3.
An Acad Bras Cienc ; 96(1): e20220698, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451623

RESUMO

The family Physaraceae (Physarales, Myxomycetes) is represented in Brazil by eight genera and 75 species. Based on data obtained from the GBIF, SpeciesLink, Flora and Funga do Brasil platforms, collections from the IPA and URM Herbaria and material collected since 1960 deposited in the UFP Herbarium, the microhabitats and distribution of Badhamiopsis (1sp.) and Badhamia (10 spp.) in Brazilian biomes are commented. An identification key for the species and the first report of B. melanospora from the state of Paraíba, B. panicea from the state of Paraná and B. ovispora from Brazil are presented.


Assuntos
Mixomicetos , Brasil , Ecossistema
4.
Microsyst Nanoeng ; 10: 31, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455383

RESUMO

This paper presents a tunable multi-threshold micro-electromechanical inertial switch with adjustable threshold capability. The demonstrated device combines the advantages of accelerometers in providing quantitative acceleration measurements and g-threshold switches in saving power when in the inactive state upon experiencing acceleration below the thresholds. The designed proof-of-concept device with two thresholds consists of a cantilever microbeam and two stationary electrodes placed at different positions in the sensing direction. The adjustable threshold capability and the effect of the shock duration on the threshold acceleration are analytically investigated using a nonlinear beam model. Results are shown for the relationships among the applied bias voltage, the duration of shock impact, and the tunable threshold. The fabricated prototypes are tested using a shock-table system. The analytical results agree with the experimental results. The designed device concept is very promising for the classification of the shock and impact loads in transportation and healthcare applications.

5.
Phys Med Biol ; 69(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38382108

RESUMO

Objective. To implement a hybrid method, which combines analytical tracking and interaction simulation using Monte Carlo (MC) techniques, in order to model photon transport inside antiscatter grids (ASG) for x-ray imaging.Approach. A new tally was developed for PENELOPE (v.2018) and penEasy (v. 2020) MC code to simulate photon transmission through ASGs. Two established analytical algorithms from the literature were implemented in this tally. In addition, a new hybrid method was introduced by extending one of the analytical algorithms to include photon-interactions inside the grid, while preserving the imaged grid structure. Calculations of primary(TP),scatter(TS),and total(TT)grid transmissions in addition to theQfactor (Q=TP2/TT) were performed. The new tally was validated for a quadric geometry ASG, and experimental measurements with a PMMA phantom of several thicknesses. In addition, the contribution of the scatter inside the grid was studied for three interspace materials, and a high resolution image of the grid was simulated.Main results. An excellent agreement was found between the two analytical models compared with the quadric grid without scatter, and the hybrid method with the geometrical grid with scatter. Average deviations of 0.2% and 1.4% were found betweenTPandTSfor the hybrid method and quadric grid, while for the hybrid method and experimental measurements these values were 1% and 20%. Antiscatter grids with aluminium as interspace material had the highest amount of scatter from inside the grid to the final image, followed up by paper fibre and air. The high resolution image of the grid was equivalent using the quadric geometry or the hybrid mode.Significance. The hybrid method provides a means of studying scattered radiation from the antiscatter grid with the advantage of higher performance, with results that are consistent with a full quadric geometry simulation of the ASG.


Assuntos
Raios X , Método de Monte Carlo , Espalhamento de Radiação , Radiografia , Imagens de Fantasmas
6.
Lancet Haematol ; 11(3): e206-e215, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335978

RESUMO

BACKGROUND: Antithymocyte globulin (ATG)-based immunosuppression is standard in front-line treatment for people with severe aplastic anaemia without a histocompatible donor or who are 40 years or older. However, ATG requires in-hospital administration, is associated with infusion-related toxicities and has limited availability worldwide. In this study, we investigated the activity and safety of an ATG-free regimen of eltrombopag with cyclosporin A as a potential treatment for patients with severe aplastic anaemia who might not have access to or cannot tolerate horse-ATG. METHODS: SOAR was a multicentre, single-arm phase 2 trial investigating eltrombopag and cyclosporin in adult (≥18 years) patients with severe aplastic anaemia who were treatment-naive and had an Eastern Cooperative Oncology Group performance status of less than 2. Participants were recruited from 20 hospitals in ten countries. Eltrombopag was initiated at 150 mg (100 mg in patients of Asian ethnicity) and cyclosporin at 10 mg/kg per day (adjusted to a trough of 200-400 µg/L) orally from day 1 to 6 months. The primary outcome was an overall haematological response rate by 6 months in the intention-to-treat population. This is the final report of the primary analysis period. The trial was registered with ClinicalTrials.gov, NCT02998645, and has been completed. FINDINGS: 54 patients were enrolled between May 11, 2017, and March 23, 2020. 34 (63%) patients were male and 20 (37%) were female. 22 (41%) were Asian, 22 (41%) were White, one (2%) was Native American or Alaska Native, one (2%) was Black or African American, and eight (15%) were other race or ethnicity. 35 patients (65%) completed 6 months of treatment with eltrombopag and cyclosporin and six (11%) completed the cyclosporin tapering period up to month 24. Overall haematological response rate by month 6 of treatment was 46% (25 of 54; 95% CI 33-60). The most reported adverse events were increased serum bilirubin (in 22 patients [41%]), nausea (16 [30%]), increased alanine aminotransferase concentration (12 [22%]), and diarrhoea (12 [22%]). Eight patients died on-treatment, but no deaths were considered related to the treatment. INTERPRETATION: Eltrombopag and cyclosporin was active as front-line treatment of severe aplastic anaemia, with no unexpected safety concerns. This approach might be beneficial where horse-ATG is not available or not tolerated. FUNDING: Novartis Pharmaceuticals.


Assuntos
Anemia Aplástica , Ciclosporina , Pirazóis , Adulto , Feminino , Humanos , Masculino , Anemia Aplástica/tratamento farmacológico , Soro Antilinfocitário/uso terapêutico , Benzoatos , Ciclosporina/uso terapêutico , Hidrazinas , Pirazóis/uso terapêutico , Quimioterapia Combinada/efeitos adversos
7.
bioRxiv ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38352511

RESUMO

Atypical enteropathogenic Escherichia coli (aEPEC) is a significant cause of diarrhea in developing countries. Some aEPEC strains, including the Brazilian representative strain of serotype O51:H40 called aEPEC 1711-4, can use flagella to attach to, invade, and persist in T84 and Caco-2 intestinal cells. They can even translocate from the gut to extraintestinal sites in a rat model. Although various aspects of the virulence of this strain were studied and the requirement of the T3SS for the efficiency of the invasion process was demonstrated, the expression of the LEE genes during the invasion and intracellular persistence remains unclear. To address this, the expression of flagella and the different LEE operons was evaluated during kinetic experiments of the interaction of aEPEC 1711-4 with enterocytes in vitro. The genome of the strain was also sequenced. The results showed that flagella expression remained unchanged, but the expression of eae and escJ increased during the early interaction and invasion of aEPEC 1711-4 into Caco-2 cells, and there was no change 24 hours post-infection during the persistence period. The number of pedestal-like structures formed on HeLa cells also increased during the 24-hour analysis. No known gene related to the invasion process was identified in the genome of aEPEC 1711-4, which was shown to belong to the global EPEC lineage 10. These findings suggest that LEE components and the intimate adherence promoted by intimin are necessary for the invasion and persistence of aEPEC 1711-4, but the detailed mechanism needs further study.

8.
Microb Cell Fact ; 23(1): 51, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355518

RESUMO

BACKGROUND: In hematologic cancers, including leukemia, cells depend on amino acids for rapid growth. Anti-metabolites that prevent their synthesis or promote their degradation are considered potential cancer treatment agents. Amino acid deprivation triggers proliferation inhibition, autophagy, and programmed cell death. L-lysine, an essential amino acid, is required for tumor growth and has been investigated for its potential as a target for cancer treatment. L-lysine α-oxidase, a flavoenzyme that degrades L-lysine, has been studied for its ability to induce apoptosis and prevent cancer cell proliferation. In this study, we describe the use of L-lysine α-oxidase (LO) from the filamentous fungus Trichoderma harzianum for cancer treatment. RESULTS: The study identified and characterized a novel LO from T. harzianum and demonstrated that the recombinant protein (rLO) has potent and selective cytotoxic effects on leukemic cells by triggering the apoptotic cascade through mitochondrial dysfunction. CONCLUSIONS: The results support future translational studies using the recombinant LO as a potential drug for the treatment of leukemia.


Assuntos
Hypocreales , Leucemia , Neoplasias , Trichoderma , Humanos , Lisina , Apoptose , Leucemia/tratamento farmacológico , Necrose
9.
J Immunol Res ; 2024: 8815767, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38375063

RESUMO

Over the last 20 years, the incidence of vertical HIV transmission has decreased from 25%-42% to less than 1%. Although there are no signs of infection, the health of HIV-exposed uninfected (HEU) infants is notoriously affected during the first months of life, with opportunistic infections being the most common disease. Some studies have reported effects on the vertical transfer of antibodies, but little is known about the subclass distribution of these antibodies. We proposed to evaluate the total IgG concentration and its subclasses in HIV+ mothers and HEU pairs and to determine which maternal factors condition their levels. In this study, plasma from 69 HEU newborns, their mothers, and 71 control pairs was quantified via immunoassays for each IgG isotype. Furthermore, we followed the antibody profile of HEUs throughout the first year of life. We showed that mothers present an antibody profile characterized by high concentrations of IgG1 and IgG3 but reduced IgG2, and HEU infants are born with an IgG subclass profile similar to that of their maternal pair. Interestingly, this passively transferred profile could remain influenced even during their own antibody production in HEU infants, depending on maternal conditions such as CD4+ T-cell counts and maternal antiretroviral treatment. Our findings indicate that HEU infants exhibit an altered IgG subclass profile influenced by maternal factors, potentially contributing to their increased susceptibility to infections.


Assuntos
Infecções por HIV , Lactente , Humanos , Recém-Nascido , Imunoglobulina G , Incidência , Contagem de Linfócito CD4 , Transmissão Vertical de Doenças Infecciosas
10.
Reprod Sci ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38393627

RESUMO

Polycystic ovary syndrome (PCOS) is a multifactorial disorder and obesity occurs in 38% to 88% of these women. Although hyperandrogenism may contribute to telomere lengthening, increased body mass index (BMI) is associated with telomere erosion. We sought to compare leukocyte telomere length (LTL) in PCOS women with normal, overweight, and obese BMI. We evaluated the relationship between LTL and clinical variables of PCOS and inflammatory biomarkers independent of BMI. A total of 348 women (243 PCOS and 105 non-PCOS) were evaluated for anthropometric measures, total testosterone, androstenedione, estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), free androgen index (FAI), fasting insulin and glycemia, lipid profile, homocysteine, C-reactive protein (CRP) and homeostatic model of insulin resistance (HOMA-IR). LTL was measured by qPCR. The PCOS group presented higher weight, waist circumference, BMI, testosterone, LH, fasting insulin, FAI, and HOMA-IR, and lower E2, SHBG, and fasting glycemia measures compared with the non-PCOS. When stratified by BMI, LTL was increased in all subgroups in PCOS compared to non-PCOS. However, in the PCOS group, LTL was lower in overweight (P = 0.0187) and obese (P = 0.0018) compared to normal-weight women. The generalized linear model showed that BMI, androstenedione, homocysteine, and CRP were associated with telomere biology. Women with PCOS had longer LTL, however, overweight or obesity progressively contributes to telomere shortening and may affect reproductive outcomes of PCOS, while androstenedione may increase LTL.

11.
Anat Rec (Hoboken) ; 307(4): 1084-1092, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36971057

RESUMO

One of the most remarkable features in sauropod dinosaurs relates to their pneumatized skeletons permeated by a bird-like air sac system. Many studies described the late evolution and diversification of this trait in mid to late Mesozoic forms but few focused on the origin of the invasive respiratory diverticula in sauropodomorphs. Fortunately, it is possible to solve this thanks to the boom of new species described in the last decade as well as the broad accessibility of new technologies. Here we analyze the unaysaurid sauropodomorph Macrocollum itaquii from the Late Triassic (early Norian) of southern Brazil using micro-computed tomography. We describe the chronologically oldest and phylogenetically earliest unambiguous evidence of an invasive air sac system in a dinosaur. Surprisingly, this species presented a unique pattern of pneumatization in non-sauropod sauropodomorphs, with pneumatic foramina in posterior cervical and anterior dorsal vertebrae. This suggests that patterns of pneumatization were not cladistically consistent prior to the arrival of Jurassic eusauropods. Additionally, we describe the protocamerae tissue, a new type of pneumatic tissue with properties of both camellae and camerae. This reverts the previous hypothesis which stated that the skeletal pneumatization first evolved into camarae, and derived into delicate trabecular arrangements. This tissue is evidence of thin camellate-like tissue developing into larger chambers. Finally, Macrocollum is an example of the gradual evolution of skeletal tissues responding to the fastly specializing Respiratory System of saurischian dinosaurs.


Assuntos
Sacos Aéreos , Dinossauros , Animais , Evolução Biológica , Dinossauros/anatomia & histologia , Microtomografia por Raio-X , Fósseis , Filogenia
12.
Anat Rec (Hoboken) ; 307(4): 1093-1112, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38088472

RESUMO

The Gondwana formations exposed in the Pranhita-Godavari Valley of central India include Middle Triassic to Lower Jurassic continental deposits that provide essential information about the tetrapod assemblages of that time, documenting some of the oldest known dinosaurs and the first faunas numerically dominated by this group. The Upper Maleri Formation of the Pranhita-Godavari Basin preserves an early-middle Norian dinosaur assemblage that provides information about the early evolutionary history of this group in central-south Gondwana. This assemblage comprises sauropodomorph dinosaurs and an herrerasaurian, including two nominal species. Here, we describe in detail the anatomy of one of those early dinosaurs, the bagualosaurian sauropodomorph Jaklapallisaurus asymmetricus. The new anatomical information is used to investigate the position of the species in an updated quantitative phylogenetic analysis focused on early sauropodomorphs. The analysis recovered Jaklapallisaurus asymmetricus as a member of Unaysauridae, at the base of Plateosauria, together with Macrocollum itaquii and Unaysaurus tolentinoi from the early Norian of southern Brazil. This phylogenetic result indicates that the dispersal of early plateosaurian sauropodomorphs between the Southern Hemisphere and what nowadays is Europe would have occurred shortly after Ischigualastian times because of the extension of their ghost lineage. Thus, the presence of early plateosaurians in the early Norian of South America and India reduces a previously inferred diachrony between the biogeographic dispersals of theropods and sauropodomorphs during post-Ischigualastian times.


Assuntos
Dinossauros , Animais , Filogenia , Dinossauros/anatomia & histologia , Osteologia , Fósseis , Evolução Biológica , Brasil
13.
Anat Rec (Hoboken) ; 307(4): 1071-1083, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37409690

RESUMO

The lineage of sauropodomorph dinosaurs raised some of the most impressive animals that ever walked on Earth. However, the massive titans of the Mesozoic Era originated from far smaller dinosaurs. The Triassic beds from Brazil yielded the earliest part of this evolutionary history. Despite the diverse fossil record of early sauropodomorphs, juvenile specimens, as well as certain species are poorly sampled. This is the case for Unaysaurus tolentinoi, an unaysaurid sauropodomorph from Caturrita Formation (ca. 225 Ma; early Norian, Late Triassic). The holotype and only specimen of U. tolentinoi was excavated from the Água Negra Locality (São Martinho da Serra, Rio Grande do Sul, Brazil) in 1998. More than two decades later, no other fossil vertebrates have been reported from the same fossiliferous site. Here we describe a skeletally immature specimen which was found in association with the holotype of U. tolentinoi. The specimen was discovered after a first-hand examination of the holotype and comprises some isolated vertebrae and elements from the posterior autopodium. According to linear regressions, its metatarsal I is approximately 41.7 mm in length, compared to approximately 75.9 mm in the holotype. The repeated elements and reduced size indicates that it does not belong to the elements originally used to erect U. tolentinoi. Rather, the specimen is assigned to U. tolentinoi by topotypy and shared morphology. In addition to the reduced size, distinct lines of evidence (e.g., neurocentral sutures; bone texture) support its assignment to a skeletally immature individual. In sum, the new material expands the record of U. tolentinoi, and represents an additional juvenile dinosaur from the Caturrita Formation.


Assuntos
Dinossauros , Animais , Filogenia , Dinossauros/anatomia & histologia , Brasil , Evolução Biológica , Fósseis
14.
Anat Rec (Hoboken) ; 307(4): 1515-1523, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37767852

RESUMO

Agudotherium gassenae is a poorly known non-mammaliaform probainognathian cynodont from the Late Triassic of southern Brazil. It is known only by mandibular remains, and its affinities within Probainognathia are unclear. Furthermore, its phylogenetic affinities were never investigated through computational analyses. In this study, we described new lower jaw remains excavated from the type locality and performed the first phylogenetic investigation of this taxon. The new specimen provides further anatomical information. The rostral region of the lower jaw was poorly preserved in the type series, leading to the interpretation that A. gassenae had three lower incisors. The new specimen demonstrates the presence of four incisors. The phylogenetic analysis positioned A. gassenae as the sister group of Prozostrodontia. This hypothesis differs from that previously presented in the former description of the taxon, in which it was considered a non-mammaliaform prozostrodont by means of character-state comparisons.


Assuntos
Fósseis , Mandíbula , Filogenia , Brasil , Arcada Osseodentária
16.
Ann Rheum Dis ; 83(4): 508-517, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38049983

RESUMO

OBJECTIVES: Ageing and inflammation are associated with clonal haematopoiesis (CH), the emergence of somatic mutations in haematopoietic cells. This study details CH in patients with systemic vasculitis in association with clinical, haematological and immunological parameters. METHODS: Patients with three forms of vasculitis were screened for CH in peripheral blood by error-corrected sequencing. Relative contributions of age and vasculitis on CH prevalence were calculated using multivariable logistic regression. Clonal hierarchies were assessed by proteogenomic single-cell DNA sequencing, and functional experiments were performed in association with CH status. RESULTS: Patients with Takayasu's arteritis (TAK; n=70; mean age=33.2 years), antineutrophil cytoplasmic antibody-associated vasculitis (AAV; n=47; mean age=55.3 years) and giant cell arteritis (GCA; n=59; mean age=71.2 years) were studied. CH, most commonly in DNMT3A and TET2, was detected in 34% (60/176) of patients versus 18% (28/151) of age-matched controls (p<0.01). Prevalence of CH was independently associated with age (standardised B=0.96, p<0.01) and vasculitis (standardised B=0.46, p<0.01), occurring in 61%, 32% and 13% of patients with GCA, AAV and TAK, respectively. Both branched and linear clonal trajectories showed myeloid-lineage bias, and CH was associated with markers of cellular activation. In GCA, mutations were detected in temporal artery biopsies, and clinical relapse correlated with CH in a dose-dependent relationship with clone size. CONCLUSIONS: Age was more strongly associated with CH prevalence than inflammation in systemic vasculitis. Clonal profile was dominated by DNMT3A mutations which were associated with relapse in GCA. CH is not likely a primary causal factor in systemic vasculitis but may contribute to inflammation.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Arterite de Células Gigantes , Arterite de Takayasu , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Arterite de Células Gigantes/epidemiologia , Arterite de Takayasu/epidemiologia , Hematopoiese Clonal , Inflamação , Recidiva
17.
Med Phys ; 51(2): 1117-1126, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38146824

RESUMO

BACKGROUND: Although the benefits of breast screening and early diagnosis are known for reducing breast cancer mortality rates, the effects and risks of low radiation doses to the cells in the breast are still ongoing topics of study. PURPOSE: To study specific energy distributions ( f ( z , D g ) $f(z,D_{g})$ ) in cytoplasm and nuclei of cells corresponding to glandular tissue for different x-ray breast imaging modalities. METHODS: A cubic lattice (500 µm length side) containing 4064 spherical cells was irradiated with photons loaded from phase space files with varying glandular voxel doses ( D g $D_{g}$ ). Specific energy distributions were scored for nucleus and cytoplasm compartments using the PENELOPE (v. 2018) + penEasy (v. 2020) Monte Carlo (MC) code. The phase space files, generated in part I of this work, were obtained from MC simulations in a voxelized anthropomorphic phantom corresponding to glandular voxels for different breast imaging modalities, including digital mammography (DM), digital breast tomosynthesis (DBT), contrast enhanced digital mammography (CEDM) and breast CT (BCT). RESULTS: In general, the average specific energy in nuclei is higher than the respective glandular dose scored in the same region, by up to 10%. The specific energy distributions for nucleus and cytoplasm are directly related to the magnitude of the glandular dose in the voxel ( D g $D_{g}$ ), with little dependence on the spatial location. For similar D g $D_{g}$ values, f ( z , D g ) $f(z,D_{g})$ for nuclei is different between DM/DBT and CEDM/BCT, indicating that distinct x-ray spectra play significant roles in f ( z , D g ) $f(z,D_{g})$ . In addition, this behavior is also present when the specific energy distribution ( F g ( z ) $F_{g}(z)$ ) is considered taking into account the GDD in the breast. CONCLUSIONS: Microdosimetry studies are complementary to the traditional macroscopic breast dosimetry based on the mean glandular dose (MGD). For the same MGD, the specific energy distribution in glandular tissue varies between breast imaging modalities, indicating that this effect could be considered for studying the risks of exposing the breast to ionizing radiation.


Assuntos
Mamografia , Radiometria , Raios X , Método de Monte Carlo , Radiometria/métodos , Mamografia/métodos , Imagens de Fantasmas , Doses de Radiação
18.
Med Phys ; 51(2): 1105-1116, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38156766

RESUMO

BACKGROUND: X-ray breast imaging modalities are commonly employed for breast cancer detection, from screening programs to diagnosis. Thus, dosimetry studies are important for quality control and risk estimation since ionizing radiation is used. PURPOSE: To perform multiscale dosimetry assessments for different breast imaging modalities and for a variety of breast sizes and compositions. The first part of our study is focused on macroscopic scales (down to millimeters). METHODS: Nine anthropomorphic breast phantoms with a voxel resolution of 0.5 mm were computationally generated using the BreastPhantom software, representing three breast sizes with three distinct values of volume glandular fraction (VGF) for each size. Four breast imaging modalities were studied: digital mammography (DM), contrast-enhanced digital mammography (CEDM), digital breast tomosynthesis (DBT) and dedicated breast computed tomography (BCT). Additionally, the impact of tissue elemental compositions from two databases were compared. Monte Carlo (MC) simulations were performed with the MC-GPU code to obtain the 3D glandular dose distribution (GDD) for each case considered with the mean glandular dose (MGD) fixed at 4 mGy (to facilitate comparisons). RESULTS: The GDD within the breast is more uniform for CEDM and BCT compared to DM and DBT. For large breasts and high VGF, the ratio between the minimum/maximum glandular dose to MGD is 0.12/4.02 for DM and 0.46/1.77 for BCT; the corresponding results for a small breast and low VGF are 0.35/1.98 (DM) and 0.63/1.42 (BCT). The elemental compositions of skin, adipose and glandular tissue have a considerable impact on the MGD, with variations up to 30% compared to the baseline. The inclusion of tissues other than glandular and adipose within the breast has a minor impact on MGD, with differences below 2%. Variations in the final compressed breast thickness alter the shape of the GDD, with a higher compression resulting in a more uniform GDD. CONCLUSIONS: For a constant MGD, the GDD varies with imaging modality and breast compression. Elemental tissue compositions are an important factor for obtaining MGD values, being a source of systematic uncertainties in MC simulations and, consequently, in breast dosimetry.


Assuntos
Mamografia , Radiometria , Raios X , Método de Monte Carlo , Radiometria/métodos , Mamografia/métodos , Imagens de Fantasmas , Doses de Radiação
19.
J Appl Microbiol ; 134(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086616

RESUMO

AIMS: We investigate extraintestinal pathogenic genes (ExPEC) related to virulence of Escherichia coli in flies from the dairy environment. METHODS AND RESULTS: We collected 217 flies from nine dairy farms, which were submitted to microbiological culture. Fifty-one E. coli were identified using mass spectrometry. Eleven dipteran families were identified, with a predominance of Muscidae, and a minor frequency of Tachinidae, Drosophilidae, Sphaeroceridae, Ulidiidae, Syrphidae, Chloropidae, Calliphoridae, Sarcophagidae, and Piophilidae. A panel of 16 virulence-encoding genes related to ExPEC infections were investigated, which revealed predominance of serum resistance (traT, 31/51 = 60.8%; ompT, 29/51 = 56.9%), iron uptake (irp2, 17/51 = 33.3%, iucD 11/51 = 21.6%), and adhesins (papC, 6/51 = 11.8%; papA, 5/51 = 9.8%). CONCLUSIONS: Our findings reveal Dipterans from milking environment carrying ExPEC virulence-encoding genes also identified in clinical bovine E. coli-induced infections.


Assuntos
Dípteros , Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Humanos , Animais , Bovinos , Escherichia coli/genética , Virulência/genética , Fazendas , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Fatores de Virulência/genética , Insetos
20.
Perinatol. reprod. hum ; 37(3): 130-134, sep.-dic. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1534969

RESUMO

Resumen Con la implementación de estrategias de cuidado perinatal, la tasa de transmisión vertical del virus de inmunodeficiencia humana (VIH) ha disminuido considerablemente en el mundo. A pesar de no mostrar cargas virales, los infantes expuestos al VIH no infectados (ENI) cursan en sus primeros meses de vida con mayores tasas de morbimortalidad. Esto se relaciona con enfermedades infecciosas por microorganismos oportunistas y menor respuesta a las vacunas en comparación con infantes sin exposición al virus, lo que sugiere alteraciones en su sistema inmunitario. En esta revisión abordamos diferentes evidencias de alteraciones en las respuestas inmunitarias innatas y adaptativas de infantes ENI que pudieran explicar esta disfuncionalidad inmunitaria. Adicionalmente, este conocimiento ayuda a entender cómo se desarrolla el sistema inmunitario desde los primeros momentos de gestación que servirán para encontrar alternativas de manejo y terapias para el bienestar de los infantes con esta condición.


Abstract With the implementation of perinatal care strategies, the rate of vertical transmission of human immunodeficiency virus (HIV) has decreased considerably worldwide. Despite the absence of viral loads, infants exposed to HIV not infected during gestation have higher morbidity and mortality rates. This is found to be related to infectious diseases by opportunistic microorganisms and lower response to vaccines in their first months of life compared to non-HIV exposed infants, suggesting alterations in their immune system. In this review we address different evidence of alterations in the innate and adaptive immune responses of HIV exposed infants that could explain their immune dysfunctionality. Additionally, this knowledge helps to understand how the immune system develops from the early stages of gestation and will serve to find management alternatives and therapies for the welfare of the infants with this condition.

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