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1.
J Endod ; 49(1): 26-35, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36356690

RESUMO

INTRODUCTION: Inflammation of the dental pulp due to caries is a highly prevalent pathology which causes intense pain. Here, we sought to correlate the clinical picture with the histopathology of the affected tissue. The interaction between nociceptive neurons and immune cells is fundamental to regulate the inflammatory response, but little is known about the glial network involved in this process, and its impact on caries pathogenesis. METHODS: This study characterized Schwann cells and other neuroimmune components in human dental pulps with reversible and symptomatic irreversible pulpitis (IP). Twenty eight human teeth were extracted for reasons beyond the scope of this study. Twelve were diagnosed as reversible and symptomatic IP respectively, and 4 as controls. The teeth were decalcified, processed for immunolabeling and analyzed with confocal microscopy. RESULTS: Symptomatic IP was characterized by a significantly higher density of neutrophils, and the release of neutrophil extracellular traps. Between IP and healthy controls, there were significant differences in the density of Schwann cells, macrophages, and neutrophils, in addition to morphological alterations. In IP, Schwann cell arborization extended toward the pulpodentinal interface along with more spindle-shaped cell bodies, while some macrophages displayed a distinct fusiform phenotype. CONCLUSIONS: The dental pulp has a complex multicellular organization and its pulpodentinal interface acts as a barrier in which Schwann and immune cells are distributed strategically to stop the progress of pathogens. A synergistic interaction of Schwann cells with immune cells creates a novel perspective to better understand the role of these glial cells and their active participation in pulpal inflammation.


Assuntos
Cárie Dentária , Pulpite , Humanos , Pulpite/patologia , Polpa Dentária/patologia , Cárie Dentária/patologia , Inflamação/patologia , Fenótipo
2.
Cells ; 10(9)2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34571916

RESUMO

The sperm flagellum is essential for the transport of the genetic material toward the oocyte and thus the transmission of the genetic information to the next generation. During the haploid phase of spermatogenesis, i.e., spermiogenesis, a morphological and molecular restructuring of the male germ cell, the round spermatid, takes place that includes the silencing and compaction of the nucleus, the formation of the acrosomal vesicle from the Golgi apparatus, the formation of the sperm tail, and, finally, the shedding of excessive cytoplasm. Sperm tail formation starts in the round spermatid stage when the pair of centrioles moves toward the posterior pole of the nucleus. The sperm tail, eventually, becomes located opposed to the acrosomal vesicle, which develops at the anterior pole of the nucleus. The centriole pair tightly attaches to the nucleus, forming a nuclear membrane indentation. An articular structure is formed around the centriole pair known as the connecting piece, situated in the neck region and linking the sperm head to the tail, also named the head-to-tail coupling apparatus or, in short, HTCA. Finally, the sperm tail grows out from the distal centriole that is now transformed into the basal body of the flagellum. However, a centriole pair is found in nearly all cells of the body. In somatic cells, it accumulates a large mass of proteins, the pericentriolar material (PCM), that together constitute the centrosome, which is the main microtubule-organizing center of the cell, essential not only for the structuring of the cytoskeleton and the overall cellular organization but also for mitotic spindle formation and chromosome segregation. However, in post-mitotic (G1 or G0) cells, the centrosome is transformed into the basal body. In this case, one of the centrioles, which is always the oldest or mother centriole, grows the axoneme of a cilium. Most cells of the body carry a single cilium known as the primary cilium that serves as an antenna sensing the cell's environment. Besides, specialized cells develop multiple motile cilia differing in substructure from the immotile primary cilia that are essential in moving fluids or cargos over the cellular surface. Impairment of cilia formation causes numerous severe syndromes that are collectively subsumed as ciliopathies. This comparative overview serves to illustrate the molecular mechanisms of basal body formation, their similarities, and dissimilarities, in somatic versus male germ cells, by discussing the involved proteins/genes and their expression, localization, and function. The review, thus, aimed to provide a deeper knowledge of the molecular players that is essential for the expansion of clinical diagnostics and treatment of male fertility disorders.


Assuntos
Corpos Basais/patologia , Centrossomo/patologia , Células Germinativas/patologia , Infertilidade Masculina/patologia , Humanos , Infertilidade Masculina/etiologia , Masculino , Espermatogênese
3.
Cells ; 10(2)2021 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672816

RESUMO

The wound healing response of fibroblasts critically depends on the primary cilium, a sensory organelle protruding into the environment and comprising a stable axonemal structure. A characteristic marker for primary cilia is acetylation of axonemal tubulin. Although formation of primary cilia is under cell cycle control, the environmental cues affecting ciliation are not fully understood. Our purpose was, therefore, to study the impact of culture conditions on cilia formation in NIH3T3 fibroblasts. We quantified ciliation in different NIH3T3 sub-cell lines and culture conditions by immunodetection of primary cilia and counting. Quantitative Western blotting, qRT-PCR, and proliferation assays completed our investigation. We observed large differences between NIH3T3 sub-cell lines in their ability to generate acetylated primary cilia that correlated with cytoplasmic tubulin acetylation. We found no increased activity of the major tubulin deacetylase, HDAC6, but instead reduced expression of the α-tubulin acetyltransferase 1 (Atat1) as being causative. Our observations demonstrate that cells with reduced expression of Atat1 and tubulin acetylation proliferate faster, eventually displacing all other cells in the population. Expression of Atat1 and tubulin acetylation are therefore selective forces in cell competition.


Assuntos
Acetiltransferases/metabolismo , Competição entre as Células/fisiologia , Tubulina (Proteína)/metabolismo , Acetilação , Acetiltransferases/genética , Animais , Cílios/metabolismo , Fibroblastos/metabolismo , Camundongos , Células NIH 3T3 , Processamento de Proteína Pós-Traducional/fisiologia
4.
Sci Rep ; 10(1): 14240, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859975

RESUMO

Development of spermatozoa requires remodelling and formation of particular structures. In elongating spermatids, the transient microtubular manchette contributes to the formation of the head-tail coupling apparatus (HTCA) and the sperm tail. The HTCA derives from the centrosome in that the proximal centriole inserts into the nuclear indentation and the distal centriole gives rise to the sperm flagellum. Although impairments in the formation of HTCA and sperm tail cause male infertility their molecular constituents are only partially known. The WD40-protein CFAP52 is implicated in motile cilia, but its relevance for male germ cell differentiation is not known. Here we show that CFAP52 is widespread expressed and localizes to a subset of microtubular structures. In male germ cells, CFAP52 is a component of the transient manchette and the sperm tail. However, expression of Cfap52 is not restricted to motile cilia-bearing cells. In NIH3T3 cells, CFAP52 localizes to the centrosome, the basal body, and the mitotic spindle poles, but not to the primary cilium. Our results demonstrate that CFAP52 is not restricted to motile cilia but instead most likely functions in constituting the centrosome/basal body matrix and the sperm tail.


Assuntos
Proteínas de Transporte/metabolismo , Cílios/metabolismo , Flagelos/metabolismo , Espermátides/metabolismo , Animais , Corpos Basais/metabolismo , Proteínas de Transporte/genética , Centríolos/metabolismo , Centrossomo/metabolismo , Cílios/genética , Citoesqueleto/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microtúbulos/metabolismo , Células NIH 3T3 , Cabeça do Espermatozoide/metabolismo , Cauda do Espermatozoide/metabolismo , Espermatogênese/fisiologia
5.
Front Cell Dev Biol ; 7: 151, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31475146

RESUMO

Terminal differentiation of male germ cells into functional spermatozoa requires shaping and condensation of the nucleus as well as the formation of sperm-specific structures. A transient microtubular structure, the manchette, is mandatory for sperm head shaping and the development of the connecting piece and the sperm tail. The connecting piece or head-to-tail coupling apparatus (HTCA) mediates the tight linkage of sperm head and tail causing decapitation and infertility when faulty. Using mice as the experimental model, several proteins have already been identified affecting the linkage complex, manchette or tail formation when missing. However, our current knowledge is far too rudimentary to even draft an interacting protein network. Depletion of the major outer dense fiber protein 1 (ODF1) mainly caused decapitation and male infertility but validated binding partners collaborating in the formation of sperm-specific structures are largely unknown. Amongst all candidate proteins affecting the HTCA when missing, the structural protein CCDC42 attracted our attention. The coiled-coil domain containing 42 (CCDC42) is important for HTCA and sperm tail formation but is otherwise largely uncharacterized. We show here that CCDC42 is expressed in spermatids and localizes to the manchette, the connecting piece and the tail. Beyond that, we show that CCDC42 is not restricted to male germ cells but is also expressed in somatic cells in which it localizes to the centrosome. Although centrosomal and sperm tail location seems to be irrespective of ODF1 we asked whether both proteins may form an interacting network in the male germ cell. We additionally considered ODF2, a prevalent protein involved in the formation of spermatid-specific cytoskeletal structures, as a putative binding partner. Our data depict for the first time the subcellular location of CCDC42 in spermatids and deepen our knowledge about the composition of the spermatid/sperm-specific structures. The presence of CCDC42 in the centrosome of somatic cells together with the obvious restricted male-specific phenotype when missing strongly argues for a compensatory function by other still unknown proteins most likely of the same family.

6.
J. health med. sci. (Print) ; 5(1): 41-50, Ene-Mar. 2019. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1151900

RESUMO

A medida que envejecemos, en la cavidad oral se producen cambios estructurales, por lo que adultos y adultos mayores requieren del uso de prótesis dental. Sin embargo, la implementación de la prótesis dental puede generar insatisfacción en relación a las diferentes funciones orofaciales. Se realizó una revisión de literatura con el propósito de determinar cómo el uso de prótesis dental afecta la función masticatoria en adultos mayores. La búsqueda consistió en artículos científicos originales en idioma español, inglés y portugués, sin límites temporales, en la base de datos PubMed y de forma manual. Se seleccionaron 45 artículos científicos tras la aplicación de filtros. El uso de prótesis dental afecta la función masticatoria en adultos y adultos mayores, siendo un factor crítico en términos de su nivel de satisfacción y calidad de vida, así como de la velocidad masticatoria, formación del bolo y preferencia de alimentos.


As we grow old, structural changes occur in the oral cavity, so elderly people require the use of dental prostheses. However, the implementation of the dental prosthesis can generate dissatisfaction in relation to the different orofacial functions. A literature review was conducted to determine how the use of dental prosthesis affects masticatory function in elderly people. The review consisted of original scientific articles in Spanish, English and Portuguese, without time limits, in the PubMed database and manually. Forty-five scientific articles were selected after the application of filters. The use of dental prosthesis affects chewing function in adults and older adults, being a critical factor in terms of their level of satisfaction and quality of life, as well as masticatory speed, bolus formation and food preference.


Assuntos
Humanos , Adulto , Idoso , Prótese Dentária , Mastigação , Envelhecimento/fisiologia , Prótese Dentária/efeitos adversos
7.
J Cell Sci ; 131(20)2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30257984

RESUMO

The centrosome, as the main microtubule-organizing center, safeguards chromosome segregation by supporting the bipolar spindle. Centrosome aberrations are causally related to chromosome segregation disorders, both characterizing cancer cells. Thus, a restriction to only having one centrosome per cell and cell cycle-dependent duplication of the centrosome is mandatory. Duplicated centrosomes remain physically connected, in order to function as a single entity, until onset of mitosis when centrosome disjunction is licensed by disassembly of linker proteins and accumulation of ß-catenin. The crucial role ß-catenin plays in centrosome disjunction inevitably demands for restricting its premature accumulation. ODF2 (also known as cenexin) is an essential centrosomal component, but its relevance for the interphase centrosome has not been elucidated. We show here that ODF2 plays a central role in centrosome cohesion. Depletion of ODF2 induces premature centrosome splitting and formation of tripolar spindles that are likely caused by the observed accumulation of centrosomal ß-catenin. Our data collectively indicate that ODF2 restricts ß-catenin accumulation at the centrosome, thus preventing premature centrosome disjunction.


Assuntos
Centrossomo/metabolismo , Proteínas de Choque Térmico/genética , beta Catenina/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos
8.
J. oral res. (Impresa) ; 6(7): 186-192, July 2017. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-998817

RESUMO

The difficulty experienced by patients with fixed orthodontic appliances in maintaining adequate oral hygiene poses a risk for dental caries. The use of probiotics has been proposed as a means of prevention. The following systematic review aims to determine the effectiveness of probiotics in the prevention of dental caries during treatment with fixed orthodontic appliances. This review was carried out according to the PRISMA guidelines. A comprehensive electronic search was conducted in the Cochrane Library, EMBASE, PubMed and Google Scholar Beta databases. The inclusion criteria included randomized controlled clinical trials involving the use of probiotics, caries and patients under fixed orthodontic treatment. The methodological quality of the articles was evaluated according to risk of bias. Of the five included studies, three reported significant differences compared to the control group. Of the others, one article reported significant decrease in the final count of microorganisms compared to the beginning of treatment. Only one study reported no differences of any kind. It was estimated that the eligible studies were of moderate methodological quality and had an unclear risk of bias, without affecting key domains for the research. It is concluded that the daily consumption of probiotics can be effective in the prevention of carious lesions in patients under fixed orthodontic treatment. However, this should be interpreted with caution and corroborated by clinical trials of better methodological quality


Assuntos
Humanos , Aparelhos Ortodônticos/efeitos adversos , Probióticos/uso terapêutico , Cárie Dentária/etiologia , Cárie Dentária/prevenção & controle
9.
Disaster Med Public Health Prep ; 11(2): 239-243, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27618881

RESUMO

OBJECTIVE: To describe and relate the main environmental risk factors in the emergency process after a large urban fire in Valparaiso, Chile, in April 2014. METHODS: An observational, cross-sectional descriptive study was performed. All 243 reports from an ad hoc web/mobile website created on the Ushahidi/Crowdmap platform were reviewed. Reports were recorded in a new database with dichotomist variables based on either the presence or absence of the relevant category in each report. RESULTS: Almost one-third of the reports presented data about garbage (30%) and chemical toilets (29%). Reports related to water, infrastructural damage, and garbage had significant associations with 4 categories by chi-square test. In the logistic regression model for chemical toilets, only the variable of water was significant (P value=0.00; model P value: 0.00; R2: 11.7%). The "garbage" category confirmed infrastructural damage (P value: 0.00), water (P value: 0.028), and vectors (P value: 0.00) as predictors (model P value: 0.00; R2: 23.09%). CONCLUSIONS: Statistically significant evidence was found for the statistical dependence of 7 out of 10 studied variables. The most frequent environmental risk factors in the reports were garbage, chemical toilets, and donation centers. The highest correlation found was for damaged infrastructure, vectors, and garbage. (Disaster Med Public Health Preparedness. 2017;11:239-243).


Assuntos
Crowdsourcing/métodos , Incêndios , Medição de Risco/métodos , Poluentes Atmosféricos/efeitos adversos , Chile , Estudos Transversais , Resíduos de Alimentos , Humanos , Fatores de Risco , Banheiros , População Urbana/tendências
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