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1.
J Vasc Access ; : 11297298241272259, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258587

RESUMO

PURPOSE: To compare primary patency after angioplasty with drug-coated balloon (DCB)-Passeo-18Lux, BIOTRONIK versus uncoated balloon in dysfunctional peripheral vascular access (PVA) for hemodialysis. MATERIAL AND METHODS: A total of 133 patients from four hospitals were randomized to receive DCB or plain old balloon angioplasty (POBA) after satisfactory treatment (residual stenosis <30%) with high pressure balloon (HPB). The primary endpoint was clinical patency of PVA 2 years after angioplasty. Secondary endpoints included the relationship between the location of stenosis and patency and also, other covariates. Mortality at 2 years was compared between both groups. RESULTS: Patency measured in days after angioplasty was higher in fistulae dilated with DCB than HPB. Kaplan-Meier survival curves showed the next percent of success (free time restenosis) after DCB versus POBA at 6 months-77.1% versus 58.2% (160.41-143.72 days until restenosis), 12 months-51.4% versus 44.3% (274.1-237.23), 18 months-38.6% versus 38% (350.74-305.18), and 24 months-37.1% versus 30.4% (419.04-369.1). At 6 months, this difference was statistically significant (p = 0.018), but not at 12 (p = 0.225), 18 (p = 0.471), or 24 months (p = 0.236). Mortality was similar in both groups. CONCLUSIONS: DCB angioplasty resulted in superior target lesion primary patency (TLPP)-free survival at 6 months of follow-up. No significant improvements in TLPP-free survival long term were observed. Mortality observed at 1 and 2 years was similar in DCB and POBA: there was no significant difference, and a safety study demonstrated no difference between the two groups (complications and mortality): DCB is safe to use in stenosis treatment in patients who are PVA carriers. LEVEL OF EVIDENCE: Level Ia, therapeutic study, RCT. EBM ratings will be based on a scale of 1-5.

2.
J Periodontol ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012429

RESUMO

BACKGROUND: Cellular cementum (CC) includes cementocytes, cells suspected to regulate CC formation or resorption as osteocytes do in bone. Sclerostin (SOST) is a secreted negative regulator of Wnt/ß-catenin signaling expressed by osteocytes and cementocytes. Osteocyte SOST expression reduces bone formation. We investigated the functional importance of SOST in CC compared with alveolar bone (AB) using a Sost knockout (Sost-/-) mouse model to better understand the role of cementocytes in CC. METHODS: Mandibles and femurs of Sost-/- and wild-type (WT) mice were analyzed at 42 and 120 days postnatal (dpn). Maxillary first molars were bilaterally extracted at 42 dpn and both AB healing (maxillary molar sockets) and CC apposition (mandibular first molars) were examined at 21 days post-procedure. Analyses included micro-computed tomography, histology, and immunohistochemistry. RESULTS: Femur cortical and trabecular bone and mandibular bone volumes were similarly increased in Sost-/- versus WT mice at 42 and/or 120 dpn. In contrast to previous reports, CC was not increased by Sost-/- at either age. We conducted challenge experiments on AB and CC to explore tissue-specific responses. Post-extraction AB healing was improved by Sost deletion. In contrast, experimentally-induced apposition in molars failed to stimulate increased CC formation in Sost-/- versus WT mice. Wnt pathway markers AXIN2 and DKK1, which were increased in Sost-/- versus WT AB osteocytes, were unchanged in cementocytes. CONCLUSIONS: These data indicate CC is less responsive than AB to SOST deletion. Within the study limitations, these results do not support cementocytes as critical for directing increased CC formation. PLAIN LANGUAGE SUMMARY: Sclerostin is a protein known to inhibit bone formation, and removing sclerostin leads to more bone formation. Cementum is the thin layer that covers the surface of the tooth's root. Previous studies suggest that inhibiting sclerostin can similarly increase the amount of cementum. We wanted to compare the response of cementum and bone when sclerostin is absent to understand similarities and differences between these two tissues. In this study, we removed the Sost gene (the gene which produces sclerostin) in mice. We found that mice without sclerostin have more bone in their legs and jaws. Moreover, mice without sclerostin also healed better after tooth removal compared with normal mice. Surprisingly, unlike previous studies, we found that the amount of cementum was not different in mice without sclerostin compared with normal mice. Additionally, we challenged the cementum by taking out the opposing tooth to cause the first mandibular molar to move up by building more cementum. Even with this challenge, we found no difference in the amount of cementum in mice lacking sclerostin compared with normal mice. Therefore, we conclude here that cementum is less sensitive to the absence of sclerostin compared with bone.

3.
J Phys Chem A ; 128(29): 6010-6018, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38994657

RESUMO

We present a deorbitalization of the recent simplified, regularized Tao-Mo exchange functional ( J. Chem. Phys. 2023, 159, 214102) that is faithful to the parent functional. That is a major gain relative to our earlier deorbitalization which did poorly on molecular heats of formation ( J. Chem. Phys. 2023, 159, 214103). The improvement arises from augmentation of the Mejía-Rodríguez and Trickey deorbitalization strategy ( Phys. Rev. A 2017, 96, 052512) to use a smoothed replacement for the reduced density Laplacian (conventionally denoted q) obtained from that Laplacian itself. The augmentation also rationalizes the improvement obtained from the cutoff of q < 0 that was poorly understood at the time of the previous paper. The new scheme yields deorbitalized chemical region indicators that are much closer to those from the parent, orbital-dependent functional than were obtainable from the previous deorbitalization. It also replicates the good 3d elemental magnetization of the parent functional reasonably well.

4.
Healthcare (Basel) ; 12(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38998777

RESUMO

(1) Background: Mental health problems are associated with negative connotations that may lead to discrimination and rejection of people diagnosed with mental disorders. The present study aimed to develop and validate a new scale (the Spanish Social Stigma Scale-S3) to assess the current level of social stigma in the general Spanish population. (2) Methods: The assessment tool was developed after reviewing the items of existing tools that represent the most appropriate indicators for the assessment of social stigma. A review was performed by volunteer subjects and by a group of experts in the field, based on the participation of 563 respondents to a survey. (3) Results: The confirmatory factor analysis revealed that the developed tool fits with the factors that determine the level of social stigma and shows good internal consistency (χ2SB = 412.0321, gl = 293, p < 0.01; BBNNFI = 0.922; CFI = 0.930; IFI = 0.931; RMSEA = 0.028 [0.022, 0.035]). (4) Conclusions: The S3 is useful for assessing knowledge, attitudes, and behavior towards people diagnosed with a mental disorder. This tool may be used for the identification and development of mechanisms necessary for the reduction of social stigma in the general population.

5.
Environ Geochem Health ; 46(9): 342, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073664

RESUMO

Mining is responsible for the release of metallic pollutants and radioactive materials into the environment, which have the potential to disrupt ecosystems and pose significant risks to human health. Significant mining activity is concentrated in the municipality of Caetité (northeastern Brazil), where Latin America's only active uranium mine and significant iron ore deposits are located. Although previous studies have shown that the regional soil and water resources are highly contaminated by various toxic elements and that exposure to these elements is known to have adverse effects on human health, the health risks in this mining region have never been assessed. The aim of this unprecedented comprehensive investigation was to assess the health, radiological and ecological risks in this mining region, which is home to nearly 100,000 people. To achieve our goal, soil and water samples were collected in the vicinity of the mines and in the main settlements in the region. Fifteen metallic toxic elements were determined using Instrumental Neutron Activation Analysis and Inductively Coupled Plasma Optical Emission Spectrometry. The HERisk code, which follows the main methodological guidelines for risk assessment, was used to quantify human health, radiological and ecological indices. The average values of the total risk and cancer risk indices indicated that region falls into the moderate risk category (1.0 ≤ HItot < 4.0). However, 63% of the sites had high risk values, with Fe, Co and As being the metals contributing most to total and cancer risk, respectively. Near the mining areas, the potential ecological risk can be considered extreme (PERI ≥ 600). The values of the calculated radiological indices correspond to typical values ​​in natural uranium areas. However, in the communities near the mine, the dose values are slightly above the permissible limit (1 mSv y-1), so they must be continuously monitored, and risk mitigation measures must be taken.


Assuntos
Mineração , Humanos , Brasil , Medição de Risco , Monitoramento Ambiental , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Exposição Ambiental , Monitoramento de Radiação
6.
Glycobiology ; 34(7)2024 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-38857376

RESUMO

Multivalency in lectins plays a pivotal role in influencing glycan cross-linking, thereby affecting lectin functionality. This multivalency can be achieved through oligomerization, the presence of tandemly repeated carbohydrate recognition domains, or a combination of both. Unlike lectins that rely on multiple factors for the oligomerization of identical monomers, tandem-repeat lectins inherently possess multivalency, independent of this complex process. The repeat domains, although not identical, display slightly distinct specificities within a predetermined geometry, enhancing specificity, affinity, avidity and even oligomerization. Despite the recognition of this structural characteristic in recently discovered lectins by numerous studies, a unified criterion to define tandem-repeat lectins is still necessary. We suggest defining them multivalent lectins with intrachain tandem repeats corresponding to carbohydrate recognition domains, independent of oligomerization. This systematic review examines the folding and phyletic diversity of tandem-repeat lectins and refers to relevant literature. Our study categorizes all lectins with tandemly repeated carbohydrate recognition domains into nine distinct folding classes associated with specific biological functions. Our findings provide a comprehensive description and analysis of tandem-repeat lectins in terms of their functions and structural features. Our exploration of phyletic and functional diversity has revealed previously undocumented tandem-repeat lectins. We propose research directions aimed at enhancing our understanding of the origins of tandem-repeat lectin and fostering the development of medical and biotechnological applications, notably in the design of artificial sugars and neolectins.


Assuntos
Lectinas , Sequências de Repetição em Tandem , Animais , Humanos , Lectinas/química , Lectinas/metabolismo
7.
Int J Mol Sci ; 24(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38069043

RESUMO

Nanotechnology has played a prominent role in biomedical engineering, offering innovative approaches to numerous treatments. Notable advances have been observed in the development of medical devices, contributing to the advancement of modern medicine. This article briefly discusses key applications of nanotechnology in tissue engineering, controlled drug release systems, biosensors and monitoring, and imaging and diagnosis. The particular emphasis on this theme will result in a better understanding, selection, and technical approach to nanomaterials for biomedical purposes, including biological risks, security, and biocompatibility criteria.


Assuntos
Sistemas de Liberação de Medicamentos , Nanoestruturas , Sistemas de Liberação de Medicamentos/métodos , Nanotecnologia/métodos , Engenharia Biomédica/métodos , Engenharia Tecidual/métodos
8.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38038712

RESUMO

In Paper I [H. Francisco, A. C. Cancio, and S. B. Trickey, J. Chem. Phys. 159, 214102 (2023)], we gave a regularization of the Tao-Mo exchange functional that removes the order-of-limits problem in the original Tao-Mo form and also eliminates the unphysical behavior introduced by an earlier regularization while essentially preserving compliance with the second-order gradient expansion. The resulting simplified, regularized (sregTM) functional delivers performance on standard molecular and solid state test sets equal to that of the earlier revised, regularized Tao-Mo functional. Here, we address de-orbitalization of that new sregTM into a pure density functional. We summarize the failures of the Mejía-Rodríguez and Trickey de-orbitalization strategy [Phys. Rev. A 96, 052512 (2017)] when used with both versions. We discuss how those failures apparently arise in the so-called z' indicator function and in substitutes for the reduced density Laplacian in the parent functionals. Then, we show that the sregTM functional can be de-orbitalized somewhat well with a rather peculiarly parameterized version of the previously used deorbitalizer. We discuss, briefly, a de-orbitalization that works in the sense of reproducing error patterns but that apparently succeeds by cancelation of major qualitative errors associated with the de-orbitalized indicator functions α and z, hence, is not recommended. We suggest that the same issue underlies the earlier finding of comparatively mediocre performance of the de-orbitalized Tao-Perdew-Staroverov-Scuseri functional. Our work demonstrates that the intricacy of such two-indicator functionals magnifies the errors introduced by the Mejía-Rodríguez and Trickey de-orbitalization approach in ways that are extremely difficult to analyze and correct.

9.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38038713

RESUMO

The revised, regularized Tao-Mo (rregTM) exchange-correlation density functional approximation (DFA) [A. Patra, S. Jana, and P. Samal, J. Chem. Phys. 153, 184112 (2020) and Jana et al., J. Chem. Phys. 155, 024103 (2021)] resolves the order-of-limits problem in the original TM formulation while preserving its valuable essential behaviors. Those include performance on standard thermochemistry and solid data sets that is competitive with that of the most widely explored meta-generalized-gradient-approximation DFAs (SCAN and r2SCAN) while also providing superior performance on elemental solid magnetization. Puzzlingly however, rregTM proved to be intractable for de-orbitalization via the approach of Mejía-Rodríguez and Trickey [Phys. Rev. A 96, 052512 (2017)]. We report investigation that leads to diagnosis of how the regularization in rregTM of the z indicator functions (z = the ratio of the von-Weizsäcker and Kohn-Sham kinetic energy densities) leads to non-physical behavior. We propose a simpler regularization that eliminates those oddities and that can be calibrated to reproduce the good error patterns of rregTM. We denote this version as simplified, regularized Tao-Mo, sregTM. We also show that it is unnecessary to use rregTM correlation with sregTM exchange: Perdew-Burke-Ernzerhof correlation is sufficient. The subsequent paper shows how sregTM enables some progress on de-orbitalization.

10.
BMJ Open ; 13(7): e072641, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37451741

RESUMO

INTRODUCTION: There is a high prevalence of mental health problems among university students. Better prediction and treatment access for this population is needed. In recent years, short-term dynamic factors, which can be assessed using experience sampling methods (ESM), have presented promising results for predicting mental health problems. METHODS AND ANALYSIS: Undergraduate students from five public universities in Spain are recruited to participate in two web-based surveys (at baseline and at 12-month follow-up). A subgroup of baseline participants is recruited through quota sampling to participate in a 15-day ESM study. The baseline survey collects information regarding distal risk factors, while the ESM study collects short-term dynamic factors such as affect, company or environment. Risk factors will be identified at an individual and population level using logistic regressions and population attributable risk proportions, respectively. Machine learning techniques will be used to develop predictive models for mental health problems. Dynamic structural equation modelling and multilevel mixed-effects models will be considered to develop a series of explanatory models for the occurrence of mental health problems. ETHICS AND DISSEMINATION: The project complies with national and international regulations, including the Declaration of Helsinki and the Code of Ethics, and has been approved by the IRB Parc de Salut Mar (2020/9198/I) and corresponding IRBs of all participating universities. All respondents are given information regarding access mental health services within their university and region. Individuals with positive responses on suicide items receive a specific alert with indications for consulting with a health professional. Participants are asked to provide informed consent separately for the web-based surveys and for the ESM study. Dissemination of results will include peer-reviewed scientific articles and participation in scientific congresses, reports with recommendations for universities' mental health policy makers, as well as a well-balanced communication strategy to the general public. STUDY REGISTRATION: osf.io/p7csq.


Assuntos
Avaliação Momentânea Ecológica , Saúde Mental , Humanos , Universidades , Estudantes/psicologia , Inquéritos e Questionários , Estudos Observacionais como Assunto
11.
J Polym Environ ; : 1-15, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-37361350

RESUMO

Proteins are abundant biomolecules found in human cells, as well as pathogenic bacteria and viruses. Some of them become pollutants when released into water. Adsorption is an advantageous method for separating proteins in aqueous media since proteins are already immobilized on solid surfaces. Adsorbents with surfaces rich in tannins are efficient due to their affinity for strong interactions with the various amino acids that make up proteins. This work aimed to develop an adsorbent for protein adsorption in aqueous medium using lignocellulosic materials modified from eucalyptus bark and vegetable tannins. A more efficient resin was prepared containing 10% eucalyptus bark fibers and 90% tannin mimosa by condensation with formaldehyde, and it was characterized by UV-Vis, FTIR-ATR spectroscopy and determinations of degree of swelling, bulk and bulk density and specific mass. For UV-Vis spectroscopy the percentage of condensed and hydrolysable tannins in the extracts of fibers of the dry husks of Eucalyptus Citriodora was estimated and it was also determined your soluble solids. The study of bovine serum albumin (BSA) adsorption was carried out in batch with quantification by UV-Vis spectroscopy. The most efficient prepared resin obtained 71.6 ± 2.78% removal in a solution of 260 mg L-1 of BSA working in a better pH range of the aqueous solution of BSA in its isoelectric point, ~ 5, 32 ± 0.02, under these conditions, the synthesized resin can reach a maximum BSA adsorption capacity of ~ 26.7 ± 0.29 mg g-1 in 7 min. The new synthesized resin presents good prospects for adsorption of proteins or species that in their structure have higher percentages of amino functional groups or amino acids with aliphatic, acidic and/or basic hydrophilic characteristics.

12.
Int J Mol Sci ; 24(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36674516

RESUMO

This study aimed to assess the obesity effects on the proteomic profile of the periodontal ligament of rats submitted to obesity induction by a high-fat diet. Eight Holtzman rats were divided into control (n = 3) and obese (n = 5) groups. The maxillae were histologically processed for laser capture microdissection of the periodontal ligament of the first maxillary molars. Peptide mixtures were analyzed by LC-MS/MS. A total of 1379 proteins were identified in all groups. Among them, 335 (24.30%) were exclusively detected in the obese group, while 129 (9.35%) proteins were uniquely found in the control group. Out of the 110 (7.98%) differentially abundant proteins, 10 were more abundant and 100 had decreased abundance in the obese group. A gene ontology analysis showed some proteins related to obesity in the "extracellular exosome" term among differentially identified proteins in the gene ontology cellular component terms Prelp, Sec13, and Sod2. These three proteins were upregulated in the obese group (p < 0.05), as shown by proteomic and immunohistochemistry analyses. In summary, our study presents novel evidence that the proteomic profile of the periodontal ligament is altered in experimental obesity induction, providing a list of differentially abundant proteins associated with obesity, which indicates that the periodontal ligament is responsive to obesity.


Assuntos
Ligamento Periodontal , Proteômica , Ratos , Animais , Ligamento Periodontal/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Proteínas/metabolismo , Obesidade/metabolismo , Proteínas da Matriz Extracelular/metabolismo
13.
Minerva Obstet Gynecol ; 75(6): 503-511, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35758093

RESUMO

BACKGROUND: To use the algorithm of the Fetal Medicine Foundation (FMF) to determine the cutoff point for prediction of preeclampsia (PE) in a Brazilian population. METHODS: Randomized clinical trial with 274 nulliparous patients at gestational age between 11 and 13 weeks and 6 days. To calculate the risk of PE, the algorithm available at the website of the FMF (http://fetalmedicine.org/research/assess/preeclampsia/first-trimester) was used. Among the patients, 138 did not use preventive measures (100 mg/day aspirin [ASA]). Youden's criteria were used to calculate the cutoff point. To test the effectiveness of 100 mg/day ASA in preventing PE, the patients were divided into two groups - at risk above and below the cutoff point. RESULTS: In the group comprising the 135 patients that did not take ASA, the median age was 22 years, the Body Mass Index (BMI) was 59.3 kg/m2, the mean arterial pressure (MAP) was 73.3 mmHg, and the mean pulsatility index of uterine artery Doppler was 1.71. The median gestational age at delivery was 39.3 (38.1-40.3) weeks. The prevalence of PE was 11.1%. In our sample, the use of 100 mg/day ASA reduced total PE by 36.3% (prevalence of PE in the group above the cutoff point was 19% and 12.1% when ASA and placebo were used, respectively). CONCLUSIONS: The cutoff point defined for prediction of PE was 1:155 with sensitivity of 80%, specificity of 57.5%, positive predictive value of 19.1%, and negative predictive value of 95%, which should help to select patients that will benefit from prophylactic ASA.


Assuntos
Pré-Eclâmpsia , Feminino , Humanos , Gravidez , Adulto Jovem , Algoritmos , Aspirina/uso terapêutico , Brasil/epidemiologia , Perinatologia , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/prevenção & controle , Primeiro Trimestre da Gravidez
14.
Physiol Mol Biol Plants ; 28(9): 1765-1784, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36387973

RESUMO

Several families of transcription factors (TFs) control the progression of senescence. Many key TFs belonging to the WRKY family have been described to play crucial roles in the regulation of leaf senescence, mainly in Arabidopsis thaliana. However, little is known about senescence-associated WRKY members in floricultural species. Delay of senescence in leaves and petals of Petunia hybrida, a worldwide ornamental crop are highly appreciated traits. In this work, starting from 28 differentially expressed WRKY genes of A. thaliana during the progression of leaf senescence, we identified the orthologous in P. hybrida and explored the expression profiles of 20 PhWRKY genes during the progression of natural (age-related) leaf and corolla senescence as well as in the corollas of flowers undergoing pollination-induced senescence. Simultaneous visualization showed consistent and similar expression profiles of PhWRKYs during natural leaf and corolla senescence, although weak expression changes were observed during pollination-induced senescence. Comparable expression trends between PhWRKYs and the corresponding genes of A. thaliana were observed during leaf senescence, although more divergence was found in petals of pollinated petunia flowers. Integration of expression data with phylogenetics, conserved motif and cis-regulatory element analyses were used to establish a list of candidates that could regulate more than one senescence process. Our results suggest that several members of the WRKY family of TFs are tightly linked to the regulation of senescence in P. hybrida. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01243-y.

15.
Orphanet J Rare Dis ; 17(1): 348, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071499

RESUMO

Fibrodysplasia ossificans progressiva (FOP) is an ultrarare condition and one of the most impactful disorders associated with progressive heterotopic ossification events. It is estimated that there are 120-150 patients in Brazil; however, currently, fewer than 100 patients have been identified, and the role of a FOP advocacy group (FOP Brazil) has been instrumental for the identification and follow-up of these individuals and families. The aim of this article is to summarize the current status of FOP in Brazil and describe strategies proposed to approach this challenge in a continental size country.


Assuntos
Miosite Ossificante , Ossificação Heterotópica , Brasil/epidemiologia , Humanos
16.
J Periodontal Res ; 57(5): 1014-1023, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35930685

RESUMO

OBJECTIVE: To define the potential of polycaprolactone (PCL) scaffold for cementoblast delivery. BACKGROUND: Dental cementum is critical for tooth attachment and position, and its regenerative capabilities remain unpredictable. METHODS: PCL scaffolds were manufactured by the electrospinning technique at 10% and 20% (w/v) and seeded with cementoblasts (OCCM-30). Scaffolds were characterized for their morphology and biological performance by scanning electron microscopy (SEM), confocal and conventional histology, cytocompatibility (PrestoBlue assay), gene expression (type I collagen - Col1; bone sialoprotein - Bsp; runt-related transcription factor 2 - Runx-2; alkaline phosphatase - Alpl; osteopontin - Opn; osteocalcin - Ocn, osterix - Osx), and the potential to induce extracellular matrix deposition and mineralization in vitro. RESULTS: Overall, data analysis showed that PCL scaffolds allowed cell adhesion and proliferation, modulated the expression of key markers of cementoblasts, and led to enhanced extracellular matrix deposition and calcium deposition as compared to the control group. CONCLUSION: Altogether, our findings allow concluding that PCL scaffolds are a viable tool to culture OCCM-30 cells, leading to an increased potential to promote mineralization in vitro. Further studies should be designed in order to define the clinical relevance of cementoblast-loaded PCL scaffolds to promote new cementum formation.


Assuntos
Materiais Biocompatíveis , Cemento Dentário , Diferenciação Celular , Sialoproteína de Ligação à Integrina/metabolismo , Poliésteres , Alicerces Teciduais
17.
Nature ; 606(7915): 646-649, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35732768
18.
Differentiation ; 124: 17-27, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35151064

RESUMO

Periodontal dental ligament (PDL) is composed of heterogeneous population of mesenchymal progenitor cells. The mechanisms that regulate the differentiation of these cells towards osteoblast/cementoblast phenotype are not fully understood. Some studies have demonstrated that is possible to change the pattern of cell differentiation via epigenetic mechanisms. The proposal of this study was to investigate whether 5-aza-2'-deoxycytidine (5-aza-dC) treatment would stimulate the osteoblast/cementoblast differentiation of periodontal ligament mesenchymal progenitor cells (PDL-CD105+ enriched cells), characterized as low osteoblast potential, through bone morphogenetic protein-2 (BMP-2) modulation. PDL-CD105+ cells from a single donor were cloned and characterized in two populations as high osteoblast/cementoblast potential (HOP) and low osteoblast/cementoblast potential (LOP) by mineralization in vitro and expression of osteogenic gene markers, such as runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN), bone morphogenetic protein 2 (BMP-2) and asporin (ASPN). Next, two LOP clones (L1 and L2) were pretreated with 5-aza-dC (10 µM) for 48 h, cultured under osteogenic condition and evaluated for mineralized matrix in vitro, transcription modulation of osteogenic gene markers, methylated and hydroxymethylated DNA levels of BMP-2 and ASPN and intracellular/extracellular expression of BMP-2 protein. LOP clones showed high expression of ASPN transcripts associated with low mRNA levels of BMP-2, RUNX2, ALP, and OCN. 5-aza-dC treatment raised hydroxymethylated DNA levels of BMP-2 and increased the expression of BMP-2 transcripts in both LOP clones. However, BMP-2 protein (intracellular and secreted forms) was detected only in L1 cell clones, in which it was observed an increased expression of osteoblast/cementoblast markers (RUNX2, ALP, OCN) associated with higher mineralization in vitro. In L2 cell clones, 5-aza-dC increased gene expression of ASPN, with no great change in for osteoblast/cementoblast differentiation potential. These data show that 5-aza-dC improves osteoblast/cementoblast differentiation of PDL-CD105+ cells via BMP-2 secretion, and this effect depends on low levels of ASPN expression.


Assuntos
Proteína Morfogenética Óssea 2 , Células-Tronco Mesenquimais , Fosfatase Alcalina , Azacitidina/farmacologia , Proteína Morfogenética Óssea 2/genética , Diferenciação Celular/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Cemento Dentário , Ligamentos , Osteoblastos , Osteocalcina , Ligamento Periodontal
19.
J Matern Fetal Neonatal Med ; 35(25): 5383-5388, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33517811

RESUMO

BACKGROUND: Predictors of spontaneous preterm birth in primigravid women remain undetermined. AIM: We evaluated whether biomarkers in vaginal secretions and/or differences in the dominant bacterium in the vaginal microbiome predicted the risk for spontaneous preterm birth in primigravid women with a cervical length >25mm. STUDY DESIGN: In a prospective study, 146 second trimester pregnant women with their first conception and a cervix >25mm were enrolled. The vaginal microbiome composition was characterized by analysis of 16S ribosomal RNA gene sequences. The concentrations of d- and l-lactic acid, matrix metalloproteinase (MMP) 2, 8 and 9 and tissue inhibitor of metalloproteinase (TIMP) 1 and 2 in vaginal secretions were measured by ELISA. Cervical length was determined by vaginal ultrasonography. Pregnancy outcome data were subsequently collected. There was a spontaneous preterm birth (SPTB) in 13 women (8.9%) while in an additional 8 women (5.5%) preterm delivery was medically indicated. Lactobacillus iners was the dominant vaginal bacterium in 61.5% of women with a SPTB but only in 31.2% of those who delivered at term (p = .0354). The vaginal concentration of TIMP-1 (p = .0419) and L-lactic acid (p = .0495) was higher in women with a SPTB as compared to those who delivered at term. Lactobacillus iners dominance was associated with elevated levels of TIMP-1 (p = .0434) and TIMP-2 (p = .0161) and lower levels of D-lactic acid (p < .0001) compared to when L. crispatus was dominant. CONCLUSION: In this exploratory study of primigravid women, elevations in vaginal TIMP-1 and L- lactic acid and L. iners dominance in the vaginal microbiome are associated with an increased occurrence of SPTB.


Assuntos
Colo do Útero , Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Colo do Útero/diagnóstico por imagem , Colo do Útero/microbiologia , Gestantes , Inibidor Tecidual de Metaloproteinase-1 , Estudos Prospectivos , Vagina/microbiologia , Bactérias , Ácido Láctico
20.
Int J Mol Sci ; 24(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36613725

RESUMO

The goal of this study was to perform a clinical and molecular investigation in an eight-year-old female child diagnosed with hypophosphatasia (HPP). The proband and her family were evaluated by medical and dental histories, biochemical analyses, radiographic imaging, and genetic analysis of the tissue-nonspecific alkaline phosphatase (ALPL) gene. A bioinformatic analysis was performed to predict the structural and functional impact of the point mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) molecule and to define their potential contribution to the phenotype. We identified a novel combination of heterozygous ALPL missense variants in the proband, p.Ala33Val and p.Asn47His, compatible with an autosomal recessive mode of inheritance and resulting in skeletal and dental phenotypes. Computational modeling showed that the affected Asn47 residue is located in the coil structure close to the N-terminal α-helix, whereas the affected Ala33 residue is localized in the N-terminal α-helix. Both affected residues are located close to the homodimer interface, suggesting they may impair TNSALP dimer formation and stability. Clinical and biochemical follow-up revealed improvements after six years of ERT. Reporting this novel combination of ALPL variants in childhood HPP provides new insights into genotype-phenotype associations for HPP and specific sites within the TNSALP molecule potentially related to a childhood-onset HPP and skeletal and dental manifestations. Beneficial effects of ERT are implicated in skeletal and dental tissues.


Assuntos
Fosfatase Alcalina , Hipofosfatasia , Feminino , Humanos , Fosfatase Alcalina/genética , Fosfatase Alcalina/química , Hipofosfatasia/genética , Mutação de Sentido Incorreto , Criança
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