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1.
J Imaging ; 10(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39057732

RESUMO

Precise annotations for large medical image datasets can be time-consuming. Additionally, when dealing with volumetric regions of interest, it is typical to apply segmentation techniques on 2D slices, compromising important information for accurately segmenting 3D structures. This study presents a deep learning pipeline that simultaneously tackles both challenges. Firstly, to streamline the annotation process, we employ a semi-automatic segmentation approach using bounding boxes as masks, which is less time-consuming than pixel-level delineation. Subsequently, recursive self-training is utilized to enhance annotation quality. Finally, a 2.5D segmentation technique is adopted, wherein a slice of a volumetric image is segmented using a pseudo-RGB image. The pipeline was applied to segment the carotid artery tree in T1-weighted brain magnetic resonance images. Utilizing 42 volumetric non-contrast T1-weighted brain scans from four datasets, we delineated bounding boxes around the carotid arteries in the axial slices. Pseudo-RGB images were generated from these slices, and recursive segmentation was conducted using a Res-Unet-based neural network architecture. The model's performance was tested on a separate dataset, with ground truth annotations provided by a radiologist. After recursive training, we achieved an Intersection over Union (IoU) score of (0.68 ± 0.08) on the unseen dataset, demonstrating commendable qualitative results.

2.
Sci Rep ; 14(1): 17169, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060360

RESUMO

Data from dry bone samples, collected from anatomical or archaeological collections, can improve the knowledge regarding accessory foot bones, including prevalence, size, shape and laterality, that can be useful in disparate fields of research, from medicine to bioarcheology. In the present study, the prevalence of six accessory foot bones (os trigonum, calcaneus secundarium, accessory navicular bone, os vesalianum, os sustentaculum and os intermetatarseum) was assessed in a sample of 486 individuals (226 females, 260 males) from the Coimbra Identified Skeletal Collection (CISC). The most frequent accessory bones are os trigonum (9.9%; 48/485) and calcaneus secundarium (6.0%; 29/486), while the most uncommon is os sustentaculum (0.4%; 2/486). No sex differences were observed. All accessory bones occur more often unilaterally, with the exception of the accessory navicular bone that, in the majority of cases, occurs bilaterally. The unilateral expression of os trigonum, calcaneus secundarium and os vesalianum was mostly in the right foot. The co-occurrence of accessory foot bones was recorded in 1.7% of the individuals (8/486), and the combinations of os trigonum and calcaneus secundarium were the most frequently observed. This research emphasizes the relevance of conducting studies on reference skeletal collections in order to gain a comprehensive understanding of anatomical variations in the foot. This understanding is crucial for accurate diagnoses and successful treatment in clinical settings, as well as for establishing population comparison standards in the fields of bioarchaeology and forensic anthropology.


Assuntos
Ossos do Pé , Humanos , Feminino , Masculino , Portugal , Ossos do Pé/anatomia & histologia , Ossos do Tarso/anormalidades , Ossos do Tarso/anatomia & histologia , Calcâneo/anatomia & histologia , Calcâneo/anormalidades , Fósseis , Pé/anatomia & histologia , Arqueologia , Adulto , Doenças do Pé
3.
Acta Cir Bras ; 39: e392824, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39046039

RESUMO

PURPOSE: to evaluate biocompatibility and osteogenic potential of hydroxyapatite/alginate composite after its implantation on rat calvarian critical bone defect. METHODS: thirty adults male Wistar rats were randomly distributed into two groups: GHA - critical bone defect filled with hydroxyapatite/alginate composite granules (HA/Alg) and CG - critical bone defect without biomaterial; evaluated at biological points of 15, 45 and 120 days. RESULTS: the histomorphometrically analyses for GHA showed osteoid matrix deposition (OM) among the granules and towards the center of the defect in centripetal direction throughout the study, with evident new bone formation at 120 days, resulting in filling 4/5 of the initial bone defect. For CG, this finding was restricted to the edges of the bone margins and formation of connective tissue on the residual area was found in all biological points. Inflammatory response on GHA was chronic granulomatous type, discrete and regressive for all biological points. Throughout the study, the CG presented mononuclear inflammatory infiltrate diffuse and regressive. Histomorphometry analyses showed that OM percentage was evident for GHA group when compared to CG group in all analyzed periods (p > 0.05). CONCLUSIONS: the biomaterial evaluated at this study showed to be biocompatible, bioactive, osteoconductive and biodegradable synchronously with bone formation.


Assuntos
Alginatos , Materiais Biocompatíveis , Regeneração Óssea , Substitutos Ósseos , Durapatita , Teste de Materiais , Ratos Wistar , Animais , Masculino , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Alginatos/farmacologia , Durapatita/farmacologia , Durapatita/uso terapêutico , Materiais Biocompatíveis/uso terapêutico , Substitutos Ósseos/uso terapêutico , Distribuição Aleatória , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Ácidos Hexurônicos/farmacologia , Ácido Glucurônico/farmacologia , Crânio/cirurgia , Crânio/efeitos dos fármacos , Fatores de Tempo , Ratos , Reprodutibilidade dos Testes
4.
Anthropol Anz ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38873814

RESUMO

Dental caries is the most prevalent chronic infectious disease during childhood both in historical and contemporary times, but research focused on the oral health of non-adults from the past is still scant. As such, this study proposes a multidisciplinary approach to the differential diagnosis of severe dental lesions in a medieval non-adult skeleton. The skeleton of a three-year-old child recovered in the medieval necropolis of Cacela Velha (Portugal) was studied through macroscopic, radiological, elemental and stable isotope analyses. This individual exhibited enamel destruction and dentine exposure in both the maxillary and mandibular teeth, with the latter also showing changes in coloration. Elemental analysis showed that his skull presented lower values of Si, Cl, and Ca and higher of Cu compared to the control, while the concentration of P and S were significantly lower in the teeth. Early childhood caries is the most probable diagnosis for the dental lesions observed, apparently stemming from a reticulate of factors that include potential malnutrition, and the consumption of sugars in complementary feeding - even though historical sources point to the scarcity of sugar in Portugal during most of the Middle Ages.

5.
J Voice ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38945728

RESUMO

OBJECTIVE: To compare and correlate musical performance anxiety (MPA) and vocal self-perception among amateur evangelical singers, focusing on the interaction between anxiety and aspects of performance in this sample. METHOD: This study employed a cross-sectional and quantitative approach, involving 75 amateur gospel singers from evangelical churches, aged between 18 and 59 years. Data collection included the administration of a sample identification and characterization questionnaire, the Brazilian Portuguese version of the Kenny Music Performance Anxiety Inventory (K-MPAI), and the Singing Voice Handicap Index (S-VHI). The descriptive analysis used absolute and relative frequencies, measures of central tendency, and dispersion (mean and standard deviation [SD]). To compare the vocal self-assessment protocols and performance aspects, the Kruskal-Wallis test was applied. Spearman's correlation test was used for correlation analysis. All analyses were conducted with a significance level set at 5% (P < 0.05). RESULTS: Vocal warm-up and cool-down activities, vocal discomfort after performance, and vocal self-assessment were significantly associated with scores on S-VHI, and the variable "instruments louder than voices" was associated with the K-MPAI score. Participants exhibited a mean K-MPAI score of 85.12 points (SD ± 36.6), and the vocal handicap of the sample had a mean score of 45.22 (SD ± 32.3). There was no statistically significant correlation between the protocols. CONCLUSION: Incorporating vocal warm-up and cool-down activities was significantly associated with lower scores on S-VHI. Conversely, those experiencing postperformance vocal discomfort exhibited higher scores on S-VHI. Moreover, the absence of correlation between the assessment protocols suggests that while significant levels of voice handicap were observed, a direct link to MPA cannot be definitively established. Overall, these findings contribute to a nuanced understanding of the multifaceted factors shaping vocal health and performance among amateur evangelical singers, thereby guiding future research and interventions in this field.

6.
PLoS Negl Trop Dis ; 18(3): e0012072, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38536893

RESUMO

Acute kidney injury (AKI) is a critical systemic complication caused by Bothrops envenoming, a neglected health problem in the Brazilian Amazon. Understanding the underlying mechanisms leading to AKI is crucial for effectively mitigating the burden of this complication. This study aimed to characterize the urinary protein profile of Bothrops atrox snakebite victims who developed AKI. We analyzed three groups of samples collected on admission: healthy subjects (controls, n = 10), snakebite victims who developed AKI (AKI, n = 10), and those who did not evolve to AKI (No-AKI, n = 10). Using liquid-chromatography tandem mass spectrometry, we identified and quantified (label-free) 1190 proteins. A panel of 65 proteins was identified exclusively in the urine of snakebite victims, with 32 exclusives to the AKI condition. Proteins more abundant or exclusive in AKI's urine were associated with acute phase response, endopeptidase inhibition, complement cascade, and inflammation. Notable proteins include serotransferrin, SERPINA-1, alpha-1B-glycoprotein, and NHL repeat-containing protein 3. Furthermore, evaluating previously reported biomarkers candidates for AKI and renal injury, we found retinol-binding protein, beta-2-microglobulin, cystatin-C, and hepcidin to be significant in cases of AKI induced by Bothrops envenoming. This work sheds light on physiological disturbances caused by Bothrops envenoming, highlighting potential biological processes contributing to AKI. Such insights may aid in better understanding and managing this life-threatening complication.


Assuntos
Injúria Renal Aguda , Fenômenos Biológicos , Bothrops , Mordeduras de Serpentes , Animais , Humanos , Mordeduras de Serpentes/complicações , Bothrops atrox , Proteômica , Injúria Renal Aguda/etiologia
7.
Anthropol Anz ; 81(3): 341-349, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38317614

RESUMO

The Megalitho da Capella (Figueira da Foz, Coimbra, Portugal) is one of at least 21 dolmens in a megalithic complex explored by António dos Santos Rocha between 1880 and 1909. Among the human remains from Megalitho da Capella is an incomplete and fragmented cranium. Santos Rocha interpreted a groove on the parietal bone as an incision of traumatic origin with signs of remodeling that was suggestive of prolonged survival after an intentional intervention. This study provides a new examination of the groove using microcomputed tomographic (microCT) imaging, microscopy, and macroscopic observations of the groove in addition to the direct dating the skeletal remains. Results indicate that the human remains are dated to the Late Neolithic and that the "incision" is a normal anatomical variant corresponding to impressions from vascular tissue and temporal projections of the squamosal. We conclude that studies of bone surface modifications should consider normal anatomical variants (e.g., sulci, grooves, and furrows) when reporting results. Paleoimaging, microscopy, and comparative observations can assist in the identification bone modifications versus anatomical variants.


Assuntos
Antropologia Física , Crânio , Microtomografia por Raio-X , Portugal , Humanos , Crânio/patologia , Crânio/lesões , Crânio/diagnóstico por imagem , Fósseis/diagnóstico por imagem
8.
J Imaging ; 10(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38392087

RESUMO

This study aims to evaluate non-invasive PET quantification methods for (R)-[11C]PK11195 uptake measurement in multiple sclerosis (MS) patients and healthy controls (HC) in comparison with arterial input function (AIF) using dynamic (R)-[11C]PK11195 PET and magnetic resonance images. The total volume of distribution (VT) and distribution volume ratio (DVR) were measured in the gray matter, white matter, caudate nucleus, putamen, pallidum, thalamus, cerebellum, and brainstem using AIF, the image-derived input function (IDIF) from the carotid arteries, and pseudo-reference regions from supervised clustering analysis (SVCA). Uptake differences between MS and HC groups were tested using statistical tests adjusted for age and sex, and correlations between the results from the different quantification methods were also analyzed. Significant DVR differences were observed in the gray matter, white matter, putamen, pallidum, thalamus, and brainstem of MS patients when compared to the HC group. Also, strong correlations were found in DVR values between non-invasive methods and AIF (0.928 for IDIF and 0.975 for SVCA, p < 0.0001). On the other hand, (R)-[11C]PK11195 uptake could not be differentiated between MS patients and HC using VT values, and a weak correlation (0.356, p < 0.0001) was found between VTAIF and VTIDIF. Our study shows that the best alternative for AIF is using SVCA for reference region modeling, in addition to a cautious and appropriate methodology.

9.
Nature ; 625(7994): 301-311, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200295

RESUMO

Western Eurasia witnessed several large-scale human migrations during the Holocene1-5. Here, to investigate the cross-continental effects of these migrations, we shotgun-sequenced 317 genomes-mainly from the Mesolithic and Neolithic periods-from across northern and western Eurasia. These were imputed alongside published data to obtain diploid genotypes from more than 1,600 ancient humans. Our analyses revealed a 'great divide' genomic boundary extending from the Black Sea to the Baltic. Mesolithic hunter-gatherers were highly genetically differentiated east and west of this zone, and the effect of the neolithization was equally disparate. Large-scale ancestry shifts occurred in the west as farming was introduced, including near-total replacement of hunter-gatherers in many areas, whereas no substantial ancestry shifts happened east of the zone during the same period. Similarly, relatedness decreased in the west from the Neolithic transition onwards, whereas, east of the Urals, relatedness remained high until around 4,000 BP, consistent with the persistence of localized groups of hunter-gatherers. The boundary dissolved when Yamnaya-related ancestry spread across western Eurasia around 5,000 BP, resulting in a second major turnover that reached most parts of Europe within a 1,000-year span. The genetic origin and fate of the Yamnaya have remained elusive, but we show that hunter-gatherers from the Middle Don region contributed ancestry to them. Yamnaya groups later admixed with individuals associated with the Globular Amphora culture before expanding into Europe. Similar turnovers occurred in western Siberia, where we report new genomic data from a 'Neolithic steppe' cline spanning the Siberian forest steppe to Lake Baikal. These prehistoric migrations had profound and lasting effects on the genetic diversity of Eurasian populations.


Assuntos
Genética Populacional , Genoma Humano , Migração Humana , Metagenômica , Humanos , Agricultura/história , Ásia Ocidental , Mar Negro , Diploide , Europa (Continente)/etnologia , Genótipo , História Antiga , Migração Humana/história , Caça/história , Camada de Gelo
11.
Clin Dermatol ; 42(1): 46-55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37858779

RESUMO

Conjunctival melanoma is quite rare, estimated at approximately 0.5 incidence per 1 million persons per year. This malignancy arises from a pre-existing nevus (7%), primary acquired melanosis (74%), or de novo without pre-existing condition (19%) and develops most often in patients with Fitzpatrick skin types I (23%) and II (62%). At initial presentation, the tumor size is approximately 13 mm in cross-sectional diameter and has 3-mm thickness, involving the bulbar (97%), forniceal (30%), tarsal (28%), or caruncular (11%) regions, often with corneal (54%) and rarely with orbital (4%) involvement. According to the eighth edition of the American Joint Committee on Cancer (AJCC), the tumor is classified as T1 (63%), T2 (18%), T3 (20%), and T4 (0%). Outcomes depend on several factors including patient age, AJCC classification, orbital invasion, and type of initial surgery, whereas tumor origin and Fitzpatrick skin type do not appear to impact outcomes. Older patients (≥70 years of age) demonstrate larger tumors, greater recurrence, and greater vision loss. Analysis of 425 patients by AJCC classification (T1 versus T2 versus T3) revealed increasing T category with greater lymph node metastasis (3% versus 13% versus 25%; P < .001), tumor-related systemic metastasis (13% versus 45% versus 40%; P < .001), and tumor-related death (8% versus 22% versus 37%; P < .001). Data of patients with orbital invasion revealed significantly greater 10-year rates of exenteration (P < .001), distant metastasis (P = .0005), and death (P = .001). Studies have demonstrated biomarkers related to conjunctival melanoma include mutations in BRAF, NRAS, ATRX, and NF1. Future therapies might be directed against these mutations or with small-molecule inhibitors and/or immunotherapy. In summary, conjunctival melanoma is a rare but ominous malignancy, imparting moderate risk for lymph node and systemic metastasis as well as death, depending on tumor features and classification. The first surgery is highly important in prevention of tumor seeding, recurrence, and metastasis.


Assuntos
Neoplasias da Túnica Conjuntiva , Melanoma , Humanos , Melanoma/terapia , Melanoma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Túnica Conjuntiva/patologia , Neoplasias da Túnica Conjuntiva/cirurgia , Metástase Linfática , Biomarcadores , Estudos Retrospectivos , Estadiamento de Neoplasias
12.
REVISA (Online) ; 13(1): 6-11, 2024.
Artigo em Português | LILACS | ID: biblio-1531557

RESUMO

A estrutura curricular interdisciplinar na construção de ementas para formação em saúde vem se tornando um diferencial singular na especialização de profissionais (Okamura, 2019). A introdução da interdisciplinaridade no meio acadêmico e currículos profissionais fornece uma estrutura para a preparação dos alunos para fazer conexões entre diferentes elos do conhecimento, aparentemente fragmentados (Ashby; Exter, 2019) e aplicá-los a problemas do mundo real.


Assuntos
Estudos Interdisciplinares , Saúde , Educação
13.
Sci Rep ; 13(1): 19902, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964077

RESUMO

The sex profile estimation of pre-historic communities is often complicated by the commingled and scattered nature of skeletal assemblages. Demographic profiles are usually lacking and provide very truncated representations of these populations but proteomic analysis of sex-specific amelogenin peptides in tooth enamel brings new promise to these studies. The main objective was to obtain the sex profile of the human assemblage recovered from the Neolithic cave-necropolis of Escoural (Montemor-o-Novo, southern Portugal) through liquid chromatography-mass spectrometry. The secondary objective was to analyse sex-specific linear enamel hypoplasias (LEH), and to test the reliability of canine odontometric sex estimation. Sex estimation through peptide analysis was carried out in 36 left permanent canines which were macroscopically examined for the presence of LEH. The canine buccolingual diameter was used for odontometric sex estimation. The obtained sex ratio (0.5:1, M:F) is biased to female individuals, probably due to cultural factors since the natural sex ratio of the human population falls between 0.95:1 and 1.02:1 (M:F). A high frequency of LEH was observed, but with no significant sexual differences (p = 0.554). The mean LEH age of onset occurred at 3 years of age, with no significant differences between the sexes (p = 0.116), and was possibly related to the weaning process. Odontometric sex estimation revealed a correct classification of 80%, with a high number of males mistakenly attributed to females. This study is one of the largest samples subjected to peptide analysis, and thus demonstrates its usefulness on the research of commingled and scattered skeletal assemblages.


Assuntos
Proteômica , Razão de Masculinidade , Masculino , Humanos , Feminino , Pré-Escolar , Portugal , Reprodutibilidade dos Testes , Peptídeos
14.
Int Arch Otorhinolaryngol ; 27(4): e672-e679, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876681

RESUMO

Introduction Changes in breathing patterns affect the harmonious development of the structures of the craniofacial system, leading to changes in posture, occlusion, and facial growth patterns. However, little is known about how these changes influence the muscle contraction patterns, either at rest or while functioning, and either in a normal or unbalanced condition. Objective To study the masseter and anterior temporal muscles fatigue during mastication in nasal- and mouth-breathing children, also considering their facial growth patterns. Methods: A total of 70 children aged 6 to 12 years old who met the study criteria were assessed. Speech-language-hearing, otorhinolaryngologic, and cephalometric assessments were performed to divide them into groups. In the electromyographic assessment, the children were asked to chew gum following a metronome until they felt fatigued. The median frequency of the muscles was analyzed at 15, 30, 45, and 60 seconds of mastication. The reported time of fatigue perception was recorded. The data were analyzed with analysis of variance (ANOVA) and the Kruskal-Wallis and the Mann-Whitney U tests. Results There were no median frequency decrease patterns nor differences in the myoelectric manifestations and reported time of fatigue between the groups. Conclusion The masticatory muscles did not reveal fatigue in the electromyographic analysis; however, the fatigue time was reported, despite the absence of physiological fatigue. The breathing mode, the facial growth pattern, and the association between them did not interfere with the behavior of the median frequency of the electromyographic signal and the fatigue time perception.

15.
Toxins (Basel) ; 15(9)2023 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-37755950

RESUMO

Bothrops snakebite envenomation (SBE) is consider an important health problem in Brazil, where Bothrops atrox is mainly responsible in the Brazilian Amazon. Local effects represent a relevant clinical issue, in which inflammatory signs and symptoms in the bite site represent a potential risk for short and long-term disabilities. Among local complications, secondary infections (SIs) are a common clinical finding during Bothrops atrox SBE and are described by the appearance of signs such as abscess, cellulitis or necrotizing fasciitis in the affected site. However, the influence of SI in the local events is still poorly understood. Therefore, the present study describes for the first time the impact of SBE wound infection on local manifestations and inflammatory response from patients of Bothrops atrox SBE in the Brazilian Amazon. This was an observational study carried out at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus (Brazil), involving victims of Bothrops SBE. Clinical and laboratorial data were collected along with blood samples for the quantification of circulating cytokines and chemokines before antivenom administrations (T0) and 24 h (T1), 48 h (T2), 72 h (T3) and 7 days after (T4). From the 94 patients included in this study, 42 presented SI (44.7%) and 52 were without SI (NSI, 55.3%). Patients classified as moderate envenoming presented an increased risk of developing SI (OR = 2.69; CI 95% = 1.08-6.66, p = 0.033), while patients with bites in hands showed a lower risk (OR = 0.20; CI 95% = 0.04-0.96, p = 0.045). During follow-up, SI patients presented a worsening of local temperature along with a sustained profile of edema and pain, while NSI patients showed a tendency to restore and were highlighted in patients where SI was diagnosed at T2. As for laboratorial parameters, leukocytes, erythrocyte sedimentation ratio, fibrinogen and C-reactive protein were found increased in patients with SI and more frequently in patients diagnosed with SI at T3. Higher levels of circulating IL-2, IL-10, IL-6, TNF, INF-γ and CXCL-10 were observed in SI patients along with marked correlations between these mediators and IL-4 and IL-17, showing a plurality in the profile with a mix of Th1/Th2/Th17 response. The present study reports for the first time the synergistic effects of local infection and envenoming on the inflammatory response represented by local manifestations, which reflected on laboratorial parameters and inflammatory mediators and thus help improve the clinical management of SI associated to Bothrops SBE.


Assuntos
Bothrops , Coinfecção , Mordeduras de Serpentes , Humanos , Animais , Mordeduras de Serpentes/complicações , Mordeduras de Serpentes/diagnóstico , Brasil/epidemiologia , Antivenenos/uso terapêutico
16.
Rev Gaucha Enferm ; 44: e20220232, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-37646757

RESUMO

OBJECTIVE: To analyze the use of Information and Communication Technologies and the interaction in a health education group with women on WhatsApp. METHODOLOGY: Descriptive-exploratory, qualitative research with mothers assisted in two Basic Health Units in Sinop - MT, part of a University Extension Project that used three health education strategies ("G-Day", "Health Tips", and "Educational Video") and project team members. Data were collected between October and December 2021 from messages in the WhatsApp group and submitted to Thematic Content Analysis. RESULTS: Two categories were identified, showing the information provided by the team and specific information requested by the mothers; the doubts expressed by the mothers mobilized the communication-interaction among the participants and little to no interaction was provoked by the health information contained in the educational strategies used. FINAL CONSIDERATION: WhatsApp proved to be an important resource/strategy in communication-interaction for health education with women.


Assuntos
Comunicação , Educação em Saúde , Feminino , Humanos , Escolaridade , Emoções , Tecnologia da Informação
17.
Phys Med ; 112: 102604, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37429182

RESUMO

PURPOSE: Positron emission tomography (PET) imaging with [18F]FDG provides valuable information regarding the underlying pathological processes in neurodegenerative disorders. PET imaging for these populations should be as short as possible to limit head movements and improve comfort. This study aimed to validate an optimized [18F]FDG-PET image reconstruction protocol aiming to reduce acquisition time while maintaining adequate quantification accuracy and image quality. METHODS: A time-reduced reconstruction protocol (5 min) was evaluated in [18F]FDG-PET retrospective data from healthy individuals and Alzheimer's disease (AD) patients. Standard (8 min) and time-reduced protocols were compared by means of image quality and quantification accuracy metrics, as well as standardized uptake value ratio (SUVR) and Z-scores (pons was used as reference). Images were randomly and blindly presented to experienced physicians and scored in terms of image quality. RESULTS: No differences between protocols were identified during the visual assessment. Small differences (p < 0.01) in the pons SUVR were observed between the standard and time-reduced protocols for healthy individuals (-0.002 ±â€¯0.011) and AD patients (-0.007 ±â€¯0.013). Likewise, incorporating the PSF correction in the reconstruction algorithm resulted in small differences (p < 0.01) in SUVR between protocols (healthy individuals: -0.003 ±â€¯0.011; AD patients: -0.007 ±â€¯0.014). CONCLUSION: Quality metrics were similar between time-reduced and standard protocols. In the visual assessment of the images, the physicians did not consider the use of PSF adequate, as it degraded the quality image. Shortening the acquisition time is possible by optimizing the image reconstruction parameters while maintaining adequate quantification accuracy and image quality.


Assuntos
Doença de Alzheimer , Fluordesoxiglucose F18 , Humanos , Estudos Retrospectivos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Doença de Alzheimer/diagnóstico por imagem
18.
Toxins (Basel) ; 15(7)2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37505684

RESUMO

Snakes of the Philodryadini tribe are included in the Dipsadidae family, which is a diverse group of rear-fanged snakes widespread in different ecological conditions, including habitats and diet. However, little is known about the composition and effects of their venoms despite their relevance for understanding the evolution of these snakes or even their impact on the occasional cases of human envenoming. In this study, we integrated venom gland transcriptomics, venom proteomics and functional assays to characterize the venoms from eight species of the Philodryadini tribe, which includes the genus Philodryas, Chlorosoma and Xenoxybelis. The most abundant components identified in the venoms were snake venom metalloproteinases (SVMPs), cysteine-rich secretory proteins (CRISPs), C-type lectins (CTLs), snake endogenous matrix metalloproteinases type 9 (seMMP-9) and snake venom serinoproteinases (SVSPs). These protein families showed a variable expression profile in each genus. SVMPs were the most abundant components in Philodryas, while seMMP-9 and CRISPs were the most expressed in Chlorosoma and Xenoxybelis, respectively. Lineage-specific differences in venom composition were also observed among Philodryas species, whereas P. olfersii presented the highest amount of SVSPs and P. agassizii was the only species to express significant amounts of 3FTx. The variability observed in venom composition was confirmed by the venom functional assays. Philodryas species presented the highest SVMP activity, whereas Chlorosoma species showed higher levels of gelatin activity, which may correlate to the seMMP-9 enzymes. The variability observed in the composition of these venoms may be related to the tribe phylogeny and influenced by their diets. In the presented study, we expanded the set of venomics studies of the Philodryadini tribe, which paves new roads for further studies on the evolution and ecology of Dipsadidae snakes.


Assuntos
Colubridae , Venenos de Serpentes , Animais , Humanos , Venenos de Serpentes/metabolismo , Colubridae/genética , Colubridae/metabolismo , Proteômica/métodos , Filogenia , Metaloproteases/genética , Metaloproteases/metabolismo , América do Sul
19.
Rev. enferm. Cent.-Oeste Min ; 13: 4834, jun. 2023.
Artigo em Português | LILACS, BDENF | ID: biblio-1537199

RESUMO

Objetivo: entender como eventos relacionais, posições sobre métodos contraceptivos e negociações com o parceiro sobre ter o filho encontram-se implicados nos engravidamentos das participantes. Método: participaram dezesseis grávidas entre 15 e 19 anos, que intencionaram o evento, selecionadas em território de vulnerabilidade social de uma capital brasileira. Foram realizadas entrevistas presenciais, orientadas por temas, com o uso adicional dos recursos: autorretrato, mapa relacional, foto-elicitação e WhatsApp, considerando preceitos da Análise de Conteúdo Temática. Resultados: os engravidamentos mostraram-se intrincados à intenção de constituir uma família com filhos, à construção de trajetórias afetivo-sexuais direcionadas a esse desfecho, com contracepção secundária, e à decisão do ter filho pouco refletida e negociada com o par, caracterizada por pressão, imposição e transferência de responsabilidade, exercida por ambos. Conclusão:a abordagem, pelos profissionais de saúde, do engravidar de adolescentes requer considerar a influência nelas imbricada de aspectos de ordem subjetiva, relacional, agencial e social.


Objective: to understand how relational events, contraceptive positions and negotiations with the partner about having a child are implicated in the participants' pregnancies. Method: A total of 16 pregnant young women aged between 15 to 19 years who became pregnant intentionally, selected from a socially vulnerable territory in a Brazilian state capital, participated in the study. Face-to-face interviews guided by themes were conducted, with additional use of the self-portrait, relational map, photo-elicitation, and WhatsApp resources, considering Thematic Content Analysis concepts. Results: the pregnancies were intimately related to the intention of building a family with children, to the construction of affective-sexual trajectories directed at this outcome, with secondary contraception, and to the decision of having a child, little reflected and negotiated, characterized by pressure, imposition and transfer of responsibility, exercised by both. Conclusion:when discussing pregnancy during adolescence, health professionals must consider the subjective, relational, agency and social aspects imbricated in such choice.


Objetivo: entender cómo los hechos relacionales, las posturas sobre los métodos anticonceptivos y las negociaciones con la pareja sobre tener un hijo intervienen en el embarazo de las participantes. Método: participaron 16 embarazadas de entre 15 y 19 años de edad que pretendían el evento, seleccionadas en un territorio de vulnerabilidad social, en una capital brasileña. Se realizaron entrevistas cara a cara, guiadas por temas, con el uso adicional de recursos de autorretrato, mapa relacional, fotoelicitación y WhatsApp; y se consideraron los preceptos del Análisis de Contenido Temático. Resultados: destacan en sus embarazos la intención de constituir una familia con hijos, la construcción de trayectorias afectivo-sexuales encaminadas a ese desenlace, con anticoncepción secundaria, y la decisión de tener un hijo poco discutida y negociada con la pareja, caracterizada por la presión, la imposición y la transferencia de responsabilidad, ejercida por ambos. Conclusión:el abordaje del embarazo en adolescentes por parte de los profesionales de la salud requiere considerar la influencia imbricada de aspectos subjetivos, relacionales, de agencia y sociales


Assuntos
Humanos , Feminino , Adolescente , Pobreza , Gravidez na Adolescência , Tomada de Decisões , Intenção , Saúde Reprodutiva
20.
J Control Release ; 357: 591-605, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37031742

RESUMO

The oral route is the most widely used and preferable way of drug administration. Several pharmacokinetic processes play a role in the distribution of administered drugs. Therefore, accurate quantification of absorption, distribution, metabolism, excretion, and characterisation of drug kinetics after oral administration is extremely important for developing new human drugs. In vivo methods, such as gamma-scintigraphy, magnetic resonance imaging (MRI), and positron emission tomography (PET), have been used to analyse gastrointestinal tract (GIT) absorption behaviour. This scoping review provides an overview of PET studies that used oral tracer administration. A systematic literature search was performed using PubMed, EMBASE, Scopus, Science Direct, and Web of Science databases. Extensive variation between these studies was seen concerning acquisition protocols, quantification methods, and pharmacokinetic outcome parameters. Studies in humans indicate that it takes 10 to 30 min for the tracer to be in the intestine and about 100 min to reach its maximum concentration in the brain. In rodent studies, different pharmacokinetic parameters for the brain, blood, and GIT were estimated, showing the potential of PET to measure the absorption and distribution of drugs and pharmaceuticals non-invasively. Finally, regarding radiation protection, oral administration has a higher absorbed dose in GIT and, consequently, a higher effective dose. However, with the recent introduction of Long Axial Field of View (LAFOV) PET scanners, it is possible to reduce the administered dose, making oral administration feasible for routine clinical studies.


Assuntos
Encéfalo , Tomografia por Emissão de Pósitrons , Humanos , Encéfalo/diagnóstico por imagem , Administração Oral , Trato Gastrointestinal/diagnóstico por imagem
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