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1.
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 , 60557 , Proteômica , Injúria Renal Aguda/etiologia
2.
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.

3.
Anthropol Anz ; 2024 Jan 29.
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.

4.
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
6.
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
7.
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
8.
Plos Neglect Trop Dis, in press, 2024
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5300

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.

9.
Toxins, v. 16, n. 2, 83, fev. 2024
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5266

RESUMO

Snake venoms have evolved in several families of Caenophidae, and their toxins have been assumed to be biochemical weapons with a role as a trophic adaptation. However, it remains unclear how venom contributes to the success of venomous species for adaptation to different environments. Here we compared the venoms from Bothrocophias hyoprora, Bothrops taeniatus, Bothrops bilineatus smaragdinus, Bothrops brazili, and Bothrops atrox collected in the Amazon Rainforest, aiming to understand the ecological and toxinological consequences of venom composition. Transcriptomic and proteomic analyses indicated that the venoms presented the same toxin groups characteristic from bothropoids, but with distinct isoforms with variable qualitative and quantitative abundances, contributing to distinct enzymatic and toxic effects. Despite the particularities of each venom, commercial Bothrops antivenom recognized the venom components and neutralized the lethality of all species. No clear features could be observed between venoms from arboreal and terrestrial habitats, nor in the dispersion of the species throughout the Amazon habitats, supporting the notion that venom composition may not shape the ecological or toxinological characteristics of these snake species and that other factors influence their foraging or dispersal in different ecological niches.

10.
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
11.
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.

12.
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
13.
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
14.
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
15.
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
16.
Toxicon ; 228: 107097, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37028563

RESUMO

Rhomb-I, a 23-kDa metalloproteinase was isolated from L. m. rhombeata venom. Its dimethylcasein proteolysis was abolished by metal chelators, and slightly enhanced by Ca2+ and Mg2+ ions, but inhibited by Co2+, Zn2+ and α2-macroglobulin. In aqueous solution, rhomb-I autoproteolyzed to a 20- and 11-kDa fragments at 37 °C. The amino acid sequence showed high homology with other snake venom metalloproteinases. Rhomb-I causes hemorrhage that may be ascribed to hydrolysis of essential basement membrane, extracellular matrix and plasma proteins. It preferentially cleaves the α-chains of fibrin (ogen). Rhomb-I inhibited convulxin- and von Willebrand factor (vWF)-induced aggregation on human platelets without significant effect on collagen-stimulated aggregation or other effectors. It digests vWF into a low-molecular-mass multimers of vWF and a rvWF-A1 domain to a 27-kDa fragment as revealed by western blotting with mouse anti-rvWF A1-domain IgG. Incubation of platelets with rhomb-I resulted in adhesion to and cleavage of platelet receptors glycoprotein (GP)Ibα and GPVI to release a 55-kDa soluble form. Both membrane glycoproteins GPIbα that binds vWF, together with GPVI which binds collagen, play a key role in mediating platelet adhesion/activation and can initiate (patho)physiological thrombus formation. Conclusions: rhomb-I is implicated in the pathophysiology of Lachesis envenoming by disrupting vasculature, hemostasis and platelet aggregation through impairing vWF-GPIb axis and blocking GPVI-collagen binding.


Assuntos
Agregação Plaquetária , Fator de von Willebrand , Humanos , Animais , Camundongos , Fator de von Willebrand/metabolismo , Metaloproteases/metabolismo , Plaquetas , Colágeno/metabolismo
17.
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
18.
Methods Protoc ; 6(2)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37104014

RESUMO

Mitochondrial dysfunction and cytosolic oxidative stress are pathological biomarkers interlinked in several chronic diseases and cellular toxicity promoted by high-energy radiation or xenobiotics. Thus, assessing the activities of the mitochondrial redox chain complexes and the cytosolic antioxidant enzymes in the same cell culture system is a valuable approach to addressing the challenge of chronic diseases or unveiling the molecular mechanisms underlying the toxicity of physical and chemical stress agents. The present article gathers the experimental procedures to obtain, from isolated cells, a mitochondria-free cytosolic fraction and a mitochondria-rich fraction. Furthermore, we describe the methodologies to evaluate the activity of the main antioxidant enzymes in the mitochondria-free cytosolic fraction (superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase), and the activity of the individual mitochondrial complexes I, II and IV, as well as the conjugated activity of complexes I-III and complexes II-III in the mitochondria-rich fraction. The protocol to test the citrate synthase activity was also considered and used to normalize complexes. The procedures were optimized within an experimental setup to allow that each condition to be tested only requires sampling of one T-25 flask of cells 2D cultured, as the typical results presented and discussed here.

19.
An. Fac. Cienc. Méd. (Asunción) ; 56(1): 25-31, 20230401.
Artigo em Espanhol | LILACS | ID: biblio-1426661

RESUMO

Objetivos: Determinar la predisposición a recibir esta vacuna contra SARS-CoV-2. Materiales y métodos: Se aplicó un diseño observacional de corte transversal en la población adulta del Paraguay entre mayo y octubre 2022. se aplicó el cuestionario de Kotta et al previamente validado, el cual fue difundido por redes sociales. Resultados: Se incluyeron 303 encuestados, con edad media 34 ± 12 años y predominio del sexo femenino (64,0%). En la muestra, 51,8% padeció COVID-19 y 97,3% ya recibió al menos una dosis de la vacuna. Se detectó que 58,4% aceptada la vacuna, 17,8% vacilaba en recibirla y 23,7% la rechazaba. La aceptación fue más frecuente en los varones (p 0,05). Conclusión: En el momento epidemiológico de disponibilidad universal de la vacuna y habiendo aún sujetos afectados por COVID-19, el rechazo a la misma fue 23,7%.


Objectives: To determine the predisposition to receive this vaccine against SARS-CoV-2. Materials and methods: An observational cross-sectional design was applied in the adult population of Paraguay between May and October 2022. The previously validated questionnaire of Kotta et al was applied, which was disseminated through social networks. Results: 303 respondents were included, with a mean age of 34 ± 12 years and predominance of the female sex (64.0%). In the sample, 51.8% suffered from COVID-19 and 97.3% have already received at least one dose of the vaccine. It was detected that 58.4% accepted the vaccine, 17.8% hesitated to receive it and 23.7% rejected it. Acceptance was more frequent in males (p 0.05). Conclusion: At the epidemiological moment of universal availability of the vaccine and with subjects still affected by COVID-19, rejection of it was 23.7%.


Assuntos
SARS-CoV-2 , COVID-19 , Vacinas , Inquéritos e Questionários , Dosagem , Objetivos , Métodos
20.
Zoo Biol ; 42(4): 577-581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959717

RESUMO

The golden lancehead (Bothrops insularis) is a critically endangered snake endemic to Queimada Grande Island, southeastern Brazil. Captive breeding programs are vital for the conservation of this species. This study evaluates the gestation of two females golden lanceheads using radiography and ultrasonography. The first female was collected on the island while reproductively active (late vitellogenesis or early pregnancy) and kept in captivity. This female gave birth to five neonates after an 8-month gestation period, which is longer than estimates based on specimens preserved in museums. The second female copulated in captivity in July and probably ovulated in October. In this case, no embryonic development was detected, and the female deposited 14 undeveloped eggs approximately 6 months after ovulation.


Assuntos
Bothrops , Feminino , Animais , Gravidez , Animais de Zoológico , Brasil
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