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1.
PLoS Comput Biol ; 19(10): e1011528, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37844076

RESUMO

Many animal species benefit from spatial learning to adapt their foraging movements to the distribution of resources. Learning involves the collection, storage and retrieval of information, and depends on both the random search strategies employed and the memory capacities of the individual. For animals living in social groups, spatial learning can be further enhanced by information transfer among group members. However, how individual behavior affects the emergence of collective states of learning is still poorly understood. Here, with the help of a spatially explicit agent-based model where individuals transfer information to their peers, we analyze the effects on the use of resources of varying memory capacities in combination with different exploration strategies, such as ordinary random walks and Lévy flights. We find that individual Lévy displacements associated with a slow memory decay lead to a very rapid collective response, a high group cohesion and to an optimal exploitation of the best resource patches in static but complex environments, even when the interaction rate among individuals is low.


Assuntos
Comportamento Alimentar , Comportamento Predatório , Humanos , Animais , Comportamento Alimentar/fisiologia , Movimento , Aprendizagem Espacial , Modelos Biológicos
2.
Mol Ther ; 31(8): 2507-2523, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37143324

RESUMO

Age-related and chemotherapy-induced bone loss depends on cellular senescence and the cell secretory phenotype. However, the factors secreted in the senescent microenvironment that contribute to bone loss remain elusive. Here, we report a central role for the inflammatory alternative complement system in skeletal bone loss. Through transcriptomic analysis of bone samples, we identified complement factor D, a rate-limiting factor of the alternative pathway of complement, which is among the most responsive factors to chemotherapy or estrogen deficiency. We show that osteoblasts and osteocytes are major inducers of complement activation, while monocytes and osteoclasts are their primary targets. Genetic deletion of C5ar1, the receptor of the anaphylatoxin C5a, or treatment with a C5AR1 inhibitor reduced monocyte chemotaxis and osteoclast differentiation. Moreover, genetic deficiency or inhibition of C5AR1 partially prevented bone loss and osteoclastogenesis upon chemotherapy or ovariectomy. Altogether, these lines of evidence support the idea that inhibition of alternative complement pathways may have some therapeutic benefit in osteopenic disorders.


Assuntos
Osteoclastos , Osteogênese , Feminino , Animais , Osteoclastos/metabolismo , Osteogênese/genética , Osteoblastos/metabolismo , Monócitos/metabolismo , Complemento C5a/genética , Complemento C5a/metabolismo
3.
Clin Oral Investig ; 27(6): 3221-3231, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36933045

RESUMO

OBJECTIVE: The aim of this study was to test the plausibility of using the ΦX174 bacteriophage as a tracer of viral aerosols spreading in a dental aerosol-generating procedure (AGP) model. METHODS: ΦX174 bacteriophage (~ 108 plaque-forming units (PFU)/mL) was added into instrument irrigation reservoirs and aerosolized during class-IV cavity preparations followed by composite fillings on natural upper-anterior teeth (n = 3) in a phantom head. Droplets/aerosols were sampled through a passive approach that consisted of Escherichia coli strain C600 cultures immersed in a LB top agar layer in Petri dishes (PDs) in a double-layer technique. In addition, an active approach consisted of E coli C600 on PDs sets mounted in a six-stage cascade Andersen impactor (AI) (simulating human inhalation). The AI was located at 30 cm from the mannequin during AGP and afterwards at 1.5 m. After collection PDs were incubated overnight (18 h at 37 °C) and bacterial lysis was quantified. RESULTS: The passive approach disclosed PFUs mainly concentrated over the dental practitioner, on the mannequin's chest and shoulder and up to 90 cm apart, facing the opposite side of the AGP's source (around the spittoon). The maximum aerosol spreading distance was 1.5 m in front of the mannequin's mouth. The active approach disclosed collection of PFUs corresponding to stages (and aerodynamic diameters) 5 (1.1-2.1 µm) and 6 (0.65-1.1 µm), mimicking access to the lower respiratory airways. CONCLUSION: The ΦX174 bacteriophage can be used as a traceable viral surrogate in simulated studies contributing to understand dental bioaerosol's behavior, its spreading, and its potential threat for upper and lower respiratory tract. CLINICAL RELEVANCE: The probability to find infectious virus during AGPs is high. This suggests the need to continue characterizing the spreading viral agents in different clinical settings through combination of passive and active approaches. In addition, subsequent identification and implementation of virus-related mitigation strategies is relevant to avoid occupational virus infections.


Assuntos
Bacteriófagos , Humanos , Escherichia coli , Clínicas Odontológicas , Odontólogos , Papel Profissional , Aerossóis
4.
Int J Mol Sci ; 24(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37511512

RESUMO

Mesenchymal stem cell (MSC)-seeded polymeric perivascular wraps have been shown to enhance arteriovenous fistula (AVF) maturation. However, the wraps' radiolucency makes their placement and integrity difficult to monitor. Through electrospinning, we infused gold nanoparticles (AuNPs) into polycaprolactone (PCL) wraps to improve their radiopacity and tested whether infusion affects the previously reported beneficial effects of the wraps on the AVF's outflow vein. Sprague Dawley rat MSCs were seeded on the surface of the wraps. We then compared the effects of five AVF treatments-no perivascular wrap (i.e., control), PCL wrap, PCL + MSC wrap, PCL-Au wrap, and PCL-Au + MSC wrap-on AVF maturation in a Sprague Dawley rat model of chronic kidney disease (n = 3 per group). Via micro-CT, AuNP-infused wraps demonstrated a significantly higher radiopacity compared to that of the wraps without AuNPs. Wraps with and without AuNPs equally reduced vascular stenoses, as seen via ultrasonography and histomorphometry. In the immunofluorescence analysis, representative MSC-seeded wraps demonstrated reduced neointimal staining for markers of infiltration with smooth muscle cells (α-SMA), inflammatory cells (CD45), and fibroblasts (vimentin) compared to that of the control and wraps without MSCs. In conclusion, AuNP infusion allows in vivo monitoring via micro-CT of MSC-seeded polymeric wraps over time, without compromising the benefits of the wrap for AVF maturation.


Assuntos
Fístula Arteriovenosa , Células-Tronco Mesenquimais , Nanopartículas Metálicas , Ratos , Animais , Ouro , Ratos Sprague-Dawley , Implantes Absorvíveis , Fístula Arteriovenosa/terapia
5.
Nanomedicine ; 39: 102465, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34571240

RESUMO

Embolic agents used in transarterial embolization for intermediate stage hepatocellular carcinoma reduce blood flow into tumors and can deliver anticancer drugs. Tumor blood supply can be interrupted using doxorubicin-eluting beads (DEB-TACE) or non-loaded beads (TAE) of different calibers. In this preclinical study, we characterized the extent of remaining stressed tumor cells after treatment, hypoxia within the surviving tumor regions, and inflammatory immune cell infiltrates after embolization with 40-60 or 70-150 µm with non-loaded or doxorubicin-loaded beads at 3 and 7 days after treatment. TAE-treated tumors had more stressed and surviving tumor cells after 3 days, irrespective of bead size, compared with DEB-TACE-treated tumors. Hypoxic stress of residual cells increased after treatment with 70-150 µm beads without or with doxorubicin. Treatment with DEB-TACE of 70-150 µm resulted in increased inflammation and proliferation in the adjacent parenchyma. Inflammatory cell infiltrates were reduced at the periphery of tumors treated with 40-60 µm DEB-TACE.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/métodos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Ratos , Resultado do Tratamento
6.
Acta Odontol Scand ; 80(7): 501-512, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35166190

RESUMO

OBJECTIVE: This 3-year multicentre randomised controlled trial compared, in 6-7-year-old Colombian children, the effectiveness of the ICCMS (International Caries Classification and Management System) with a conventional caries-management system (CCMS) in terms of individual caries-risk, caries lesions, and secondarily, oral-health-related knowledge/attitudes/practices, and number of appointments. MATERIAL AND METHODS: With ethical approval, 240 6-7-year olds from six Colombian clinics were recruited. Trained examiners conducted the following baseline/follow-up assessments: Caries risk (Cariogram-ICCMS); caries severity/activity staging (ICDAS-merged combined radiographic/visual); sealants/fillings/missing teeth, and oral-health-related knowledge, attitudes and practices. Children received their randomly allocated (ICCMS/CCMS) care from dental practitioners. Outcomes: caries-risk control (children); caries-progression control (tooth surfaces); oral-health-related knowledge/attitudes/practices improvement (parents/children), and appointments' number (children). Descriptive and non-parametric/parametric bivariate analyses were performed. RESULTS: Three-year-follow-up: n = 187 (77.9%; ICCMS: n = 92; CCMS: n = 95) disclosed a baseline-to-3-year overall high-caries-risk children decrease (ICCMS: 60.9-0%, p < .001; CCMS: 54.7-5.3%, p < .001) (p > .05). ICCMS versus CCMS showed: fewer tooth-surface caries progression (6.2% vs 7.1%, p = .010) and fewer active-caries lesions (49.8% vs. 59.1%, p < .05); higher proportion of children with ≥2/day fluoride-toothpaste tooth-brushing practice (p < .05); similar mean number of appointments (10.9 ± 5.9 vs. 10.0 ± 3.8, p = .15). CONCLUSION: Both caries-management systems showed similar effectiveness in caries-risk control, with ICCMS more effectively controlling tooth-surface caries progression and improving toothbrushing practices.


Assuntos
Cárie Dentária , Cremes Dentais , Criança , Cárie Dentária/terapia , Suscetibilidade à Cárie Dentária , Odontólogos , Fluoretos , Humanos , Papel Profissional
7.
BMC Oral Health ; 21(1): 329, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210281

RESUMO

BACKGROUND: Comprehensive caries care has shown effectiveness in controlling caries progression and improving health outcomes by controlling caries risk, preventing initial-caries lesions progression, and patient satisfaction. To date, the caries-progression control effectiveness of the patient-centred risk-based CariesCare International (CCI) system, derived from ICCMS™ for the practice (2019), remains unproven. With the onset of the COVID-19 pandemic a previously planned multi-centre RCT shifted to this "Caries OUT" study, aiming to assess in a single-intervention group in children, the caries-control effectiveness of CCI adapted for the pandemic with non-aerosols generating procedures (non-AGP) and reducing in-office time. METHODS: In this 1-year multi-centre single-group interventional trial the adapted-CCI effectiveness will be assessed in one single group in terms of tooth-surface level caries progression control, and secondarily, individual-level caries progression control, children's oral-health behaviour change, parents' and dentists' process acceptability, and costs exploration. A sample size of 258 3-5 and 6-8 years old patients was calculated after removing half from the previous RCT, allowing for a 25% dropout, including generally health children (27 per centre). The single-group intervention will be the adapted-CCI 4D-cycle caries care, with non-AGP and reduced in-office appointments' time. A trained examiner per centre will conduct examinations at baseline, at 5-5.5 months (3 months after basic management), 8.5 and 12 months, assessing the child's CCI caries risk and oral-health behaviour, visually staging and assessing caries-lesions severity and activity without air-drying (ICDAS-merged Epi); fillings/sealants; missing/dental-sepsis teeth, and tooth symptoms, synthetizing together with parent and external-trained dental practitioner (DP) the patient- and tooth-surface level diagnoses and personalised care plan. DP will deliver the adapted-CCI caries care. Parents' and dentists' process acceptability will be assessed via Treatment-Evaluation-Inventory questionnaires, and costs in terms of number of appointments and activities. Twenty-one centres in 13 countries will participate. DISCUSSION: The results of Caries OUT adapted for the pandemic will provide clinical data that could help support shifting the caries care in children towards individualised oral-health behaviour improvement and tooth-preserving care, improving health outcomes, and explore if the caries progression can be controlled during the pandemic by conducting non-AGP and reducing in-office time. TRIAL REGISTRATION: Retrospectively-registered-ClinicalTrials.gov-NCT04666597-07/12/2020: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000AGM4&selectaction=Edit&uid=U00019IE&ts=2&cx=uwje3h . Protocol-version 2: 27/01/2021.


Assuntos
COVID-19 , Cárie Dentária , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Suscetibilidade à Cárie Dentária , Odontólogos , Humanos , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Pandemias/prevenção & controle , Papel Profissional , Estudos Retrospectivos , SARS-CoV-2 , Adulto Jovem
8.
Appl Opt ; 59(22): 6737-6743, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749379

RESUMO

To calculate the conic constants of the primary and secondary mirrors of any aplanatic two-mirror telescope, nonexact equations have been used considering third-order approximations, although it was not considered that there is an infinite number of conic constants. In this paper, exact nonlinear equations are obtained; with them, the two conic constants of the mirrors are calculated without approximations. We also find that the conic constants depend on the position at the stop where the calculation is carried out, and there are always residual aberrations. In addition, a procedure is established for the exact calculation of the baffles. Finally, examples show the differences between exact and third-order calculations.

9.
J Vasc Interv Radiol ; 30(12): 2009-2015.e1, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31202678

RESUMO

PURPOSE: To characterize angiographic and cross-sectional imaging anatomy of the rat visceral vasculature in 2 translational models. MATERIALS AND METHODS: Animal studies were conducted in accordance with institutional guidelines and approval of the Institutional Animal Care and Use Committees. Retrospective review of digital subtraction arteriography was performed in 65 Wistar and 50 Sprague-Dawley male rats through a left common carotid artery or right common femoral artery approach. MR imaging of the abdomen was performed on the rats to correlate imaging modalities. RESULTS: Aortography was performed in 3 locations, including cranial to the celiac artery, cranial to the renal arteries, and cranial to the caudal (inferior) mesenteric artery, enabling characterization of the visceral branch arteries in all 65 Wistar rats. Selective arteriography of first-, second-, and third-order branch vessels of the aorta was performed allowing characterization of normal and variant anatomy. Dedicated selective arteriography was performed of the celiac artery in 65 Wistar and 10 Sprague-Dawley rats, of the common hepatic artery in 65 Wistar and 50 Sprague-Dawley rats, and of the cranial mesenteric artery in 43 Wistar rats. MR imaging enabled correlation with the lobar and portal venous anatomy. CONCLUSIONS: Analysis of arteriography and MR imaging in these rat models will provide translational researchers with anatomic details needed to develop new endovascular protocols for small animal research in interventional radiology.


Assuntos
Angiografia Digital , Aorta/diagnóstico por imagem , Aortografia , Artéria Celíaca/diagnóstico por imagem , Pesquisa Translacional Biomédica , Vísceras/irrigação sanguínea , Animais , Angiografia por Ressonância Magnética , Masculino , Modelos Animais , Veia Porta/diagnóstico por imagem , Valor Preditivo dos Testes , Ratos Sprague-Dawley , Ratos Wistar , Estudos Retrospectivos
10.
Int J Paediatr Dent ; 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30431189

RESUMO

AIM: To describe the 2-year clinical and combined with radiographic caries progression pattern in three cohorts of 2-(a), 4-(b), and 6-yr-old children (c). DESIGN: Baseline sample comprised 600 children (each-cohort: n = 200). Children's dental surfaces were clinically assessed at schools without air-drying (epi) in terms of: Clinical (C) caries lesions (d/D) with ICDASepi-merged system (C-ICDASepi-d/D:Sound/Initial-epi/Moderate/Extensive); fillings (f/F), and missing teeth (m/M). Clinical ICDAS (C) and Radiographic ICDAS (R) indexes were combined (C + R). Caries experience (dmf + DMF) was expressed as: C-dmfs + DMFS (Moderate/Extensive-d/D); C-ICDASepi-dmfs + DMFS (including Initial-epi-d/D); C + R-dmfs + DMFS; and C + R-ICDASepi-dmfs + DMFS. Follow-up caries progression corresponded to more severe caries score. RESULTS: Two-year follow-up sample was n = 352 (58.7%-baseline sample): a: n = 81; b: n = 131; c: n = 140. Around 100% of children presented C + R-ICDASepi-dmf + DMF ≥ 1, with following C + R-ICDASepi-dmfs + DMFS means: a: 7.3 ± 14.1; b: 12.2 ± 19.5; c: 13.3 ± 16.9. Progression was about 60% in all cohorts, mainly corresponding, in cohort b and c, to occlusal and distal surfaces of lower first/second-molar-primary teeth, and in cohort a to buccal surfaces of upper primary-incisor teeth. The addition of radiographs increased caries mean and prevalence in 10% as compared to only visual examination. CONCLUSIONS: Children showed a high C + R caries experience progression rate, mainly related to occlusal and proximal surfaces in lower-molar teeth and buccal in upper-incisor teeth.

11.
Phys Rev Lett ; 119(14): 140603, 2017 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-29053283

RESUMO

We solve an adaptive search model where a random walker or Lévy flight stochastically resets to previously visited sites on a d-dimensional lattice containing one trapping site. Because of reinforcement, a phase transition occurs when the resetting rate crosses a threshold above which nondiffusive stationary states emerge, localized around the inhomogeneity. The threshold depends on the trapping strength and on the walker's return probability in the memoryless case. The transition belongs to the same class as the self-consistent theory of Anderson localization. These results show that similarly to many living organisms and unlike the well-studied Markovian walks, non-Markov movement processes can allow agents to learn about their environment and promise to bring adaptive solutions in search tasks.

12.
Malar J ; 16(1): 300, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747199

RESUMO

BACKGROUND: The recent scale-up in malaria control measures in Latin America has resulted in a significant decrease in the number of reported cases in several countries including Ecuador, where it presented a low malaria incidence in recent years (558 reported cases in 2015) with occasional outbreaks of both Plasmodium falciparum and Plasmodium vivax in the coastal and Amazonian regions. This success in malaria control in recent years has led Ecuador to transition its malaria policy from control to elimination. RESULTS: This study evaluated the general knowledge, attitude and practices (KAP) about malaria, as well as its prevalence in four communities of an endemic area in northwest Ecuador. A total of 258 interviews to assess KAP in the community indicated that most people in the study area have a basic knowledge about the disease but did not use to contribute to its control. Six hundred and forty-eight blood samples were collected and analysed by thick blood smear and real-time PCR. In addition, the distribution of the infections was mapped in the study communities. Although, no parasites were found by microscopy, by PCR the total malaria prevalence was 7.5% (6.9% P. vivax and 0.6% P. falciparum), much higher than expected and comparable to that reported in endemic areas of neighbouring countries with higher malaria transmission. Serology using ELISA and immunofluorescence indicated 27% respondents for P. vivax and 22% respondents for P. falciparum. CONCLUSIONS: Results suggest that despite a great malaria reduction in Ecuador, transition from control to elimination would demand further improvement in malaria diagnostics, including active case detection to identify and treat parasite asymptomatic carriers, as well as community participation in its elimination.


Assuntos
Infecções Assintomáticas/epidemiologia , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Equador/epidemiologia , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Pessoa de Meia-Idade , Plasmodium falciparum/fisiologia , Plasmodium vivax/fisiologia , Prevalência , Adulto Jovem
13.
Acta Odontol Scand ; 75(1): 12-20, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27776449

RESUMO

OBJECTIVE: To report (1) the caries experience prevalence and mean, and the caries severity and distribution patterns, expressed clinically and combined with radiographs with the conventional and ICCMS™ systems in young children from Bogotá, Colombia; (2) the contribution of including radiographs to the clinical caries scoring and (3) in which surfaces the radiograph adds to the clinical caries registration. MATERIAL AND METHODS: Six hundred children from kindergartens/schools were enrolled: Cohort A: 2-year (n = 200), Cohort B: 4-year (n = 200) and Cohort C: 6-year (n = 200) olds. Radiographs were taken of the 4- and 6- year olds. Children were examined clinically using the Clinical (C) and Radiographic (R) ICCMS™-epi Caries Scoring Systems, staging caries lesions (d) as: Initial (Cepi/RA), Moderate (CM/RB) or Extensive (CE/RC). Caries experience including missing (m) and filled (f) surfaces was expressed as follows: clinical conventional (CdMEmfs); clinical ICCMS™ (CdepiMEmfs); combined conventional (C + RdMEmfs) and combined ICCMS™ (C + RdepiMEmfs). RESULTS: The prevalence of CdMEmfs was: Cohort A: 32%; Cohort B: 59%; Cohort C: 67.5%, increasing to 73.5%, 99.8% and 100%, respectively, with the C + R depiMEmfs. The CdMEmfs means doubled when initial caries lesions (Cdepi) and radiographs (R) were included. The d component corresponded to over two-thirds of the caries experience. Findings on the radiographs significantly raised caries experience prevalence and means (p < .02), detecting primarily approximal lesions. Surfaces with highest caries frequency were occlusal/approximal of molar teeth and buccal of upper incisor teeth. CONCLUSION: Participants' caries experience was high. The radiographic assessment significantly contributed to caries experience. Molar and upper incisor teeth were most prone to caries.


Assuntos
Índice CPO , Cárie Dentária/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Colômbia/epidemiologia , Cárie Dentária/diagnóstico por imagem , Restauração Dentária Permanente/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Incisivo/diagnóstico por imagem , Masculino , Dente Molar/diagnóstico por imagem , Exame Físico , Prevalência , Radiografia Interproximal/métodos , Coroa do Dente/diagnóstico por imagem , Desmineralização do Dente/patologia , Perda de Dente/epidemiologia , Dente Decíduo/diagnóstico por imagem
17.
Braz Oral Res ; 38: e050, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922210

RESUMO

Accurate determination of the prevalence of erosive tooth wear (ETW) and associated risk factors in adolescents can inform clinical management guidelines. The aim of this analytical cross-sectional study was to estimate the prevalence, severity, and risk factors of ETW in adolescents aged 12-15 years in the municipality of Usaquén in Bogotá, Colombia. Two calibrated examiners clinically assessed ETW using Basic Erosive Wear Examination (BEWE) Index (range: 0-3). All tooth surfaces (excluding proximal) were scored to allow estimation of the Highest (0-3) and Total BEWE (sum of Highest BEWE score per sextant: 0-18) scores per patient. Sociodemographic characteristics, ETW risk factors, and caries severity (ICDAS-epi-merged) were evaluated, and their association with the presence of ETW (indicated by a Highest BEWE score of 2-3) was examined using preliminary analyses and logistic regression models. The study sample included 454 adolescents (mean age: 13.5±1.1 years; female: 61.7%), and the prevalence of ETW was 71.6%. The majority of participants exhibited a Highest BEWE score of 3 (58.0%) and a Total BEWE score ≤8 (84.3%). The preliminary analysis showed an association between the presence of ETW and age, caries, and brushing teeth before eating (p-value < 0.05). Risk factors for ETW included always brushing teeth before eating [adjusted Prevalence Ratio (PRa) 1.31, p-value=0.014], presence of extensive carious lesions (PRa 1.23, p-value = 0.024), male gender (PRa 1.14, p-value = 0.028), and age > 14 years (PRa 1.17, p-value = 0.009). Although ETW was highly prevalent, most Colombian adolescents exhibited low Total BEWE scores. ETW was associated with frequent fruit intake, age, toothbrushing habits, caries lesions, and sex.


Assuntos
Cárie Dentária , Fatores Socioeconômicos , Erosão Dentária , Humanos , Colômbia/epidemiologia , Adolescente , Feminino , Masculino , Estudos Transversais , Erosão Dentária/epidemiologia , Erosão Dentária/etiologia , Fatores de Risco , Prevalência , Criança , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Índice de Gravidade de Doença , Fatores Etários , Distribuição por Sexo , Distribuição por Idade , Fatores Sexuais , Modelos Logísticos
18.
Lasers Med Sci ; 28(6): 1519-25, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23337926

RESUMO

Delayed, or type IV, hypersensitivity reactions are a useful model to study the effects of new substances on the immune system. In this study, the experimental model of the delayed type hypersensitivity (DTH) reaction to ovalbumin (OVA) was used to evaluate the immunomodulating effects of low-level laser therapy (LLLT), which is used as an adjuvant therapy in medicine, dentistry, and physical therapy because of its potential anti-inflammatory and analgesic effects observed in several studies. The effects of LLLT (λ 780 nm, 0.06 W/cm(2) of radiation, and fluency of 3.8 J/cm(2)) in reaction to ovalbumin in Balb/C mice were examined after the induction phase of the hypersensitivity reaction. The animals treated with azathioprine (AZA), the animals that received a vehicle instead of ovalbumin, and those not immunized served as controls (n = 6 for each group). Footpad thickness measurements and hematoxylin-eosin histopathological exams were performed. Proliferation tests were also performed (spontaneous, in the presence of concanavalin A and ovalbumin) to determine the production in mononuclear cells cultures of tumor necrosis factor-alpha (TNF-α), INF-γ, and IL-10. In the group of animals irradiated with lasers and in the group treated with AZA, footpad thickness measurements were significantly reduced in comparison to the control group (p < 0.05). This reduction was accompanied by a very significant reduction in the density of the inflammatory infiltrate and by a significant reduction in the levels of TNF-α, INF-γ, and IL-10. LLLT radiation was shown to have an immunomodulating effect on DTH to OVA in Balb/C mice.


Assuntos
Hipersensibilidade Tardia/prevenção & controle , Interferon gama/biossíntese , Interleucina-10/biossíntese , Terapia com Luz de Baixa Intensidade , Fator de Necrose Tumoral alfa/biossíntese , Animais , Azatioprina/farmacologia , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/patologia , Terapia de Imunossupressão/métodos , Imunossupressores/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia
19.
Invest Radiol ; 58(12): 894-902, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37403975

RESUMO

BACKGROUND: Extracellular matrix stiffness represents a barrier to effective local and systemic drug delivery. Increasing stiffness disrupts newly formed vessel architecture and integrity, leading to tumor-like vasculature. The resulting vascular phenotypes are manifested through different cross-sectional imaging features. Contrast-enhanced studies can help elucidate the interplay between liver tumor stiffness and different vascular phenotypes. PURPOSE: This study aims to correlate extracellular matrix stiffness, dynamic contrast-enhanced computed tomography, and dynamic contrast-enhancement ultrasound imaging features of 2 rat hepatocellular carcinoma tumor models. METHODS AND MATERIALS: Buffalo-McA-RH7777 and Sprague Dawley (SD)-N1S1 tumor models were used to evaluate tumor stiffness by 2-dimensional shear wave elastography, along with tumor perfusion by dynamic contrast-enhanced ultrasonography and contrast-enhanced computed tomography. Atomic force microscopy was used to calculate tumor stiffness at a submicron scale. Computer-aided image analyses were performed to evaluate tumor necrosis, as well as the percentage, distribution, and thickness of CD34+ blood vessels. RESULTS: Distinct tissue signatures between models were observed according to the distribution of the stiffness values by 2-dimensional shear wave elastography and atomic force microscopy ( P < 0.05). Higher stiffness values were attributed to SD-N1S1 tumors, also associated with a scant microvascular network ( P ≤ 0.001). Opposite results were observed in the Buffalo-McA-RH7777 model, exhibiting lower stiffness values and richer tumor vasculature with predominantly peripheral distribution ( P = 0.03). Consistent with these findings, tumor enhancement was significantly greater in the Buffalo-McA-RH7777 tumor model than in the SD-N1S1 on both dynamic contrast-enhanced ultrasonography and contrast-enhanced computed tomography ( P < 0.005). A statistically significant positive correlation was observed between tumor perfusion on dynamic contrast-enhanced ultrasonography and contrast-enhanced computed tomography in terms of the total area under the curve and % microvessel tumor coverage ( P < 0.05). CONCLUSIONS: The stiffness signatures translated into different tumor vascular phenotypes. Two-dimensional shear wave elastography and dynamic contrast-enhanced ultrasonography adequately depicted different stromal patterns, which resulted in unique imaging perfusion parameters with significantly greater contrast enhancement observed in softer tumors.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias Hepáticas , Ratos , Animais , Ratos Sprague-Dawley , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Ultrassonografia , Técnicas de Imagem por Elasticidade/métodos , Matriz Extracelular/patologia , Meios de Contraste
20.
Heliyon ; 9(2): e13276, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36816322

RESUMO

Here, a comprehensive review of sugarcane industrialization and its relationship with bioactive compounds (BCs) detected in various products and by-products generated during its processing is presented. Furthermore, it is discussed how these compounds have revealed important antioxidant, antineoplastic, antidiabetic, and antimicrobial activities. From this bibliographic research highlights the significance of two types of BCs of natural origin (phenolic compounds (PCs) and terpenoids) and a group of compounds synthesized during industrial transformation processes (Maillard reaction products (MRPs)). It was found that most of the studies about the BCs from sugarcane have been conducted by identifying, isolating, and analyzing ones or a few compounds at a specific period, this being a conventional approach. However, given the complexity of the synthesis processes of all these BCs and the biological activities they can manifest in a specific biological context, novel approaches are needed to address these analyses holistically. To overcome this challenge, integrating massive and multiscale methods, such as omics sciences, seems necessary to enrich these studies. This work is intended to contribute to the state of the art that could support future research about the exploration, characterization, or evaluation of different bioactive molecules from sugarcane and its derivatives.

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