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2.
Arch Cardiol Mex ; 94(1): 25-32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507327

RESUMO

BACKGROUND: Systemic hypertension (SH) is the main risk factor to cognitive deterioration, whereas visuospatial memory is more vulnerable to ageing. Some antihypertensive agents have a neuroprotector effect, however, such effects could be masked by comorbidities and/or the lack of effective control on the arterial pressure of patients. OBJECTIVE: To assess this, the evaluation of incidental visuospatial memory of SH patients and the relation to the treatment received and the effective control of pressure were made. METHOD: 80 patients (46 woman) were included grouped by the received medication: angiotensin 2 receptor blockers (ARB) or angiotensin converting enzyme inhibitors (ACEI). A multiple correlation analysis between visuospatial scores and clinical variables was made; also, a mixed model analysis (fixed factors: treatment, pressure control, diabetes comorbidity; aleatory factors: age, schooling, months from SH diagnoses). RESULTS: Half of the patients had a controlled pressure, from them the higher proportion received ARB, and a minor number of patients received ACEI. The normotensive patients receiving ACEI were inefficient whereas the hypertensive patients were more efficient. The systolic pressure was negatively related with the visuospatial scores in spite of no correlations occurred with MoCA and Raven tests. CONCLUSIONS: The visuospatial incidental/intentional scores were negatively correlated with systolic pressure. The efficiency in the visuospatial ability depends on the interaction of treatment and effective control of blood pressure. The interaction between treatment and effective pressure control must be taken in count when cognitive deterioration is studied.


ANTECEDENTES: La hipertensión arterial sistémica (HAS) es el principal factor de riesgo para el deterioro cognitivo; por otro lado, la memoria visuoespacial es más vulnerable al envejecimiento. Algunos fármacos antihipertensivos tienen un efecto neuroprotector, pero tal efecto puede enmascararse o bien no manifestarse por comorbilidad o por falta de control efectivo de la presión arterial. OBJETIVO: Evaluar las alteraciones en la memoria visuoespacial incidental de pacientes con HAS en relación con su tratamiento antihipertensivo y su control de la presión. MÉTODO: Se incluyeron 80 pacientes con HAS (46 mujeres), agrupados por su medicación en bloqueadores de los receptores de la angiotensina II (BRA) o inhibidores de la enzima convertidora de angiotensina (IECA). Se realizó un análisis de correlaciones múltiples para los puntajes obtenidos en la prueba de memoria visuoespacial incidental/intencional y un análisis de modelos mixtos (factores fijos: tratamiento, control de la presión y comorbilidad con diabetes; factores aleatorios: edad, escolaridad, meses desde el diagnóstico de HAS y coeficiente intelectual). RESULTADOS: De los pacientes controlados, la mayoría de los que recibían BRA fueron eficientes y los que recibían IECA fueron deficientes. De los que recibían IECA, los descontrolados hipertensos fueron más eficientes que los normotensos. La memoria visuoespacial se correlacionó negativamente con la presión sistólica a pesar de no haber diferencias en MoCA y Raven. CONCLUSIONES: La eficiencia en la memoria visuoespacial dependió de la interacción del tratamiento y el control de la presión. Ambos factores, tratamiento y control efectivo de la presión, deben considerarse en la evaluación del deterioro cognitivo asociado a la HAS.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Hipertensão , Feminino , Humanos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Antagonistas de Receptores de Angiotensina/farmacologia , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea
3.
Microorganisms ; 12(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543675

RESUMO

Copper nanoparticles (Cu NPs) show promise in dentistry for combating bacterial dysbiosis and tooth decay. Understanding their effects on commensal versus pathogenic bacteria is vital for maintaining oral health balance. While Cu NPs demonstrate antibacterial properties against various oral bacteria, including common pathogens associated with tooth decay, their impact on commensal bacteria requires careful examination. In our work, we analyzed three types of Cu NPs for their effects on the growth, viability, and biofilm formation of representative caries-associated and commensal oral bacteria. S. sanguinis showed high tolerance to all Cu NPs, while L. rhamnosus was highly sensitive. Oxide-Cu NPs exhibited a stronger inhibitory effect on pathobionts compared with commensal bacteria. Moreover, the biofilm formation of the key cariogenic bacteria S. mutans was reduced, with minimal negative effects on commensal species' biofilm formation. All our results showed that CuO nanoparticles (CuO NPs) exhibit reduced toxicity toward commensal bacteria growth and development but have a strong impact on pathogens. This suggests their potential for targeted treatments against pathogenic bacteria, which could help in maintaining the balance of the oral bacterial community.

4.
J Oral Biol Craniofac Res ; 14(1): 55-60, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38226333

RESUMO

Background: Brazil has a larger number of adolescent offenders, but studies evaluating their oral health are still limited. Objective: Assess the association between salivary flow and caries experience in youngsters deprived of liberty. Methodology: Sixty-eight male adolescents in conflict with the law, aged between 15 and 19 years, from a Socio-Educational Assistance Center in Brazil participated in the present study. They answered a structured questionnaire, and oral examination was performed by the Decayed, Missing, and Filled Teeth (DMFT) index. The salivary flow rate was obtained using the mechanically stimulated total saliva method. Adjusted Poisson regression was used for the association with total DMFT and its decayed component, using the salivary flow (continuous fashion) or the hyposalivation (≤1 ml/min) as independent variables. Results: Participants were divided into two groups, those who did not have any decayed teeth at the moment of the examination (n = 39) and those who had at least one decayed tooth (n = 29). Moreover, two groups were formed based on the DMFT: those who had DMFT = 0 (n = 20) and those who had DMFT≥1 (n = 48). In the multivariate analysis, hyposalivation was associated with DMFT≥1 (p = 0.048), but when the salivary flow was included, no significant association with DMFT index was identified (p = 0.178). Conversely, the presence of at least one decayed tooth was significantly associated with the salivary flow (p = 0.004), but not with hyposalivation (p = 0.091). Conclusions: Institutionalized adolescents who present hyposalivation or low salivary flow are associated with DMFT≥1 index or presence of at least one decayed tooth, respectively.

5.
Cureus ; 15(2): e35374, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36974230

RESUMO

Autoimmune polyglandular syndrome type I (APS1) shows common features such as mucocutaneous candidiasis, hypoparathyroidism, and hypoadrenalism. The clinical manifestations and their onset are highly variable. Besides endocrine abnormalities, patients can present with dental problems, keratoconjunctivitis, fever, rash, chronic diarrhea, and autoimmune hepatitis. We discuss the case of a 5-year-old female who presented initially with a new-onset seizure due to severe hypocalcemia and was diagnosed with primary hypoparathyroidism. Because she also had a history of chronic mucocutaneous candidiasis, chronic diarrhea, and the presence of autoantibodies tested positive, the diagnosis of APS1 was suspected. Genetic testing detected a novel pathogenic homozygous AIRE mutation, which confirmed the diagnosis. She began multidisciplinary treatment with antifungals, calcium supplements, and parathyroid hormone analogs.

6.
Sleep Vigil ; : 1-10, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36644371

RESUMO

Purpose: This study aimed to assess the quality of sleep and associated factors among dental students. Methods: All dental students regularly enrolled at the Federal University of Pelotas, Brazil, were invited to participate. A structured online questionnaire was applied to collect the independent variables, including academic performance. Quality of sleep was assessed by the validated version of the Pittsburgh Sleep Quality Index. Sample was dichotomized as good sleep quality (total score: ≤ 4) and at least poor quality (total score: ≥ 5). Adjusted analyses were performed using Poisson regression with robust variance to detect the association between sleep quality and independent variables. Independent adjusted models were performed to the whole-sample, only undergraduate and only graduate dental students. Results: Poor quality of sleep was detected in 266 (65.2%) dental students, of which 228 (68.9%) and 38 (49.4%) were undergraduate and graduate dental students, respectively. Female students presented a prevalence ratio (PR) 19% higher compared to males (95% confidence interval [CI] 1.01-1.41). When only graduate students were considering, those that reported not being the head of the family presented a PR 4.39 higher for poor quality of sleep (95% CI 1.91-10.09). Poor quality of sleep was associated with lower academic performance among undergraduate students (PR: 0.94; 95% CI 0.89-0.99), but not significantly associated when graduate students are considered (PR: 0.99; 95% CI 0.96-1.03). Conclusion: It was concluded that dental students, mainly female ones, have high prevalence of poor quality of sleep, which is associated with undergraduate student's worst academic performance. Supplementary Information: The online version contains supplementary material available at 10.1007/s41782-022-00223-2.

7.
Clin Oral Investig ; 26(2): 1155-1172, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35072769

RESUMO

OBJECTIVE: This network meta-analysis (NMA) assessed the antiplaque and anti-inflammatory efficacy of different sugar-free chewing gums (SFCG) as adjuncts to toothbrushing. MATERIAL AND METHODS: PubMed, Scopus, EMBASE, Web of Science, and CENTRAL databases were searched up to February 2021 to identify randomized controlled trials, involving adults, comparing antiplaque and anti-inflammatory effects of SFCG, with different active ingredients, as adjunctive to mechanical control of biofilm, with a minimum of 7-day of follow-up. Plaque and gingival indexes were assessed. The risk of bias assessment was performed with the RoB 2.0 tool. NMA, and pairwise meta-analyses were performed for both dental plaque and gingival indexes. RESULTS: Twelve studies were included, comprising 850 (antiplaque) and 1459 (gingival inflammation) subjects randomized into 9 interventions: (1) chlorhexidine; (2) chlorhexidine + xylitol (CHX+Xyl); (3) green tea + xylitol (GT+Xyl); (4) magnolia; (5) Lactobacillus reuteri; (6) vitamin C + xylitol; (7) vitamin + carbamide; (8) eucalyptus; and (9) negative control, sorbitol, gum base only, or no chewing gum. No statistically significant differences were detected among SFCG, with different active ingredients, for both antiplaque and anti-inflammatory efficacy (p > 0.05). However, SFCG with GT+XyL outperformed negative control gums regarding antiplaque efficacy (SMD, - 2.93; 95% CrI, - 0.45 to - 5.38). The SUCRA results showed that SFCG containing GT+Xyl was ranked first, for both antiplaque and anti-inflammatory outcomes. CONCLUSION: SFCG containing GT+Xyl showed better antiplaque effect over negative controls. However, cautious interpretation is required due to the low number of direct comparisons arms. These shortcomings underscore the need for RCTs with mostly head-to-head comparison that provide more conclusive evidence. CLINICAL RELEVANCE: There is no robust evidence for the clinical indications of sugar-free chewing gums as adjunct to toothbrushing for the control of biofilm or the treatment of gingivitis.


Assuntos
Placa Dentária , Gengivite , Adulto , Goma de Mascar , Placa Dentária/prevenção & controle , Humanos , Metanálise em Rede , Escovação Dentária , Xilitol
8.
Food Chem ; 370: 130991, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509947

RESUMO

Food producers have leaned towards alternative natural and synthetic sweeteners in food formulations to satisfy market demands. Even so, several synthetic sweeteners (e.g., aspartame, saccharin, sucralose) are becoming less popular due to health-related concerns, lower nutritional values, and controversies around their safety. Conversely, natural sweeteners confer favourable customer perceptions due to their association to a healthier lifestyle and higher nutritional values. This article discusses the evidence of natural sweeteners in the available commercial products. A comprehensive review of natural sweeteners is presented, which includes their resources, properties and extraction methods, as well as a discussion on several emerging technologies that offer improvements to the traditional extraction methods. Finally, the progress of natural sweeteners in the food industry is assessed, and the commercial food products containing these natural sweeteners are mentioned.


Assuntos
Aspartame , Edulcorantes , Indústria Alimentícia , Sacarina
9.
Front Cell Dev Biol ; 9: 800351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970552

RESUMO

Mammalian fertilization is a complex process involving a series of successive sperm-egg interaction steps mediated by different molecules and mechanisms. Studies carried out during the past 30 years, using a group of proteins named CRISP (Cysteine-RIch Secretory Proteins), have significantly contributed to elucidating the molecular mechanisms underlying mammalian gamete interaction. The CRISP family is composed of four members (i.e., CRISP1-4) in mammals, mainly expressed in the male tract, present in spermatozoa and exhibiting Ca2+ channel regulatory abilities. Biochemical, molecular and genetic approaches show that each CRISP protein participates in more than one stage of gamete interaction (i.e., cumulus penetration, sperm-ZP binding, ZP penetration, gamete fusion) by either ligand-receptor interactions or the regulation of several capacitation-associated events (i.e., protein tyrosine phosphorylation, acrosome reaction, hyperactivation, etc.) likely through their ability to regulate different sperm ion channels. Moreover, deletion of different numbers and combination of Crisp genes leading to the generation of single, double, triple and quadruple knockout mice showed that CRISP proteins are essential for male fertility and are involved not only in gamete interaction but also in previous and subsequent steps such as sperm transport within the female tract and early embryo development. Collectively, these observations reveal that CRISP have evolved to perform redundant as well as specialized functions and are organized in functional modules within the family that work through independent pathways and contribute distinctly to fertility success. Redundancy and compensation mechanisms within protein families are particularly important for spermatozoa which are transcriptionally and translationally inactive cells carrying numerous protein families, emphasizing the importance of generating multiple knockout models to unmask the true functional relevance of family proteins. Considering the high sequence and functional homology between rodent and human CRISP proteins, these observations will contribute to a better understanding and diagnosis of human infertility as well as the development of new contraceptive options.

10.
Rev Med Chil ; 149(3): 385-392, 2021 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-34479317

RESUMO

BACKGROUND: The rates of organ donation are alarmingly low in Chile. AIM: To determine the relationship between social and family characteristics that influence the decision to donate organs and tissues among adults. MATERIAL AND METHODS: The questionnaire developed in Spain by the international collaborative project on organ transplantation and donation, developed and validated in Chile was applied to 383 adults aged 40 ± 17 years (mostly women), living in Coquimbo, Chile. RESULTS: Seventy seven percent of respondents would agree to be a donor. The main features of eventual donors are: being young adult in 62% of respondents, single in 48%, with complete secondary education in 29%, non-practicing Catholic in 37% and being informed on television about transplantation in 66%. In a logistic regression model, the features significantly associated with being an eventual donor were the decision of donating organs of relatives (Odds Ratio [OR] 9.1 95% confidence intervals [CI] 4.8-17-2), commenting and knowing the opinion of relatives (OR 2.3 95%CI 1.2-4.1), especially parents and partner, and a lower age (OR 0.98 95% CI 0.96-0.99). CONCLUSIONS: The decision to donate organs is influenced by commenting and knowing the opinion of relatives, especially parents and partners. Also, a lower age is associated with a better attitude towards donation.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Chile , Características da Família , Feminino , Humanos , Inquéritos e Questionários , Doadores de Tecidos , Adulto Jovem
11.
Ticks Tick Borne Dis ; 12(6): 101811, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34411794

RESUMO

This paper presents data on free-living ticks collected by flagging and using CO2 traps in three natural areas in Costa Rica: Carara National Park (CNP), Palo Verde National Park (PVNP), and a Private Forest Reserve in Sarapiquí (SPR). Data were analyzed calculating aspects of alpha diversity (species richness, entropy; dominance index, and evenness); and for beta diversity, compositional similarity between communities of ticks was also calculated. We collected 12,795 ticks belonging to 10 species: Amblyomma coelebs, Amblyomma dissimile, Amblyomma mixtum, Amblyomma naponense, Amblyomma cf. oblongoguttatum, Amblyomma cf. parvum, Amblyomma sabanerae, Amblyomma tapirellum, Haemaphysalis juxtakochi and Ixodes affinis. The number of species and individuals varied between sites: 5970 ticks were collected in CNP, 4443 in PVNP, and 2382 in SPR. Amblyomma cf. oblongoguttatum and A. cf. parvum were collected at all three sites, but A. mixtum was the most abundant species, even though it was not collected in SPR. Values of alpha diversity were calculated for CNP and SPR, while diversity in PVNP was the lowest of the three locations. Evenness was highest in SPR and lowest in CNP. The only community that presented dominance was PVNP. Beta diversity showed low similarity between the three locations with the lowest being CNP and SPR. For the three localities, estimates of the number of tick species based on presence/absence data was higher using flagging than CO2; and considering the stage of the ticks collected. More larvae were captured using CO2 traps than by flagging, while flagging was better for collecting adults. To our knowledge this is the first study in Costa Rica that compares these two sampling methods in three different environmental areas.


Assuntos
Distribuição Animal , Biodiversidade , Ixodes/fisiologia , Animais , Costa Rica , Meio Ambiente , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Parques Recreativos
12.
Horiz. sanitario (en linea) ; 20(2): 237-242, may.-ago. 2021. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1346299

RESUMO

Resumen Objetivo: Determinar el cumplimiento del indicador de Prevención de Infecciones de Vías Urinarias en Pacientes con Sonda Vesical Instalada, en una institución hospitalaria de segundo nivel en Tamaulipas, México. Materiales y Métodos: Estudio descriptivo de tipo transversal. La muestra estuvo conformada por 80 pacientes con sonda vesical instalada. Se utilizó el instrumento Prevención de Infecciones de Vías urinarias en Pacientes con Sonda Vesical Instalada (F1-PIVUPSVI/05) y una cédula sociodemográfica, para analizar los datos se utilizó el paquete estadístico SPSS-20. Resultados: En la población predominó el sexo femenino con un 56.3%. El servicio con mayor prevalencia con sonda vesical instalada fue medicina interna con 35% y cirugía general con 31%. El cumplimiento de indicador fue bajo (rojo) con un 62.5% (50) correspondiente a la escala de semaforización de ≤70%, 33.8% (27) medio (amarillo) equivalente a >70≤90 y solo el 3.8% (3) alto. Conclusiones: El cumplimiento del indicador de Prevención de Infecciones de Vías Urinarias en Pacientes con Sonda Vesical Instalada es bajo de acuerdo con la semaforización del sistema INDICAS, los criterios que se encontraron con mayor porcentaje de cumplimiento fueron los relacionados a el sistema de drenaje permanentemente conectado, registra datos de funcionamiento y bolsa colectora se mantiene por debajo del nivel de la vejiga.


Abstract Objective: To determine compliance with the indicator of Prevention of Urinary Tract Infections in Patients with a Bladder catheter installed in a second level hospital institution in Matamoros, Tamaulipas. Materials and Methods: Descriptive cross-sectional study. The sample consisted of 80 patients with a bladder catheter installed. The instrument Prevention of urinary tract infections in patients with an installed bladder catheter (F1-PIVUPSVI / 05) and a sociodemographic card were used. The statistical package SPSS-20 was used to analyze the data. Results: In the population, the female sex predominated with 56.3%. The service with the highest prevalence with a bladder catheter installed was internal medicine with 35% and general surgery with 31%. Indicator compliance was low (red) with 62.5% (50) corresponding to the signaling scale of ≤70%, 33.8% (27) medium (yellow) equivalent to> 70≤90 and only 3.8% (3) tall. Conclusions: Compliance with the indicator of prevention of urinary tract infections in patients with a bladder catheter installed is low according to the signaling of the INDICAS system, the criteria found with the highest percentage of compliance were those related to the permanently connected drainage system, records Operating data and collection bag is kept below the level of the bladder.

13.
Rev. méd. Chile ; 149(3): 385-392, mar. 2021. tab
Artigo em Espanhol | LILACS | ID: biblio-1389470

RESUMO

Background: The rates of organ donation are alarmingly low in Chile. Aim: To determine the relationship between social and family characteristics that influence the decision to donate organs and tissues among adults. Material and Methods: The questionnaire developed in Spain by the international collaborative project on organ transplantation and donation, developed and validated in Chile was applied to 383 adults aged 40 ± 17 years (mostly women), living in Coquimbo, Chile. Results: Seventy seven percent of respondents would agree to be a donor. The main features of eventual donors are: being young adult in 62% of respondents, single in 48%, with complete secondary education in 29%, non-practicing Catholic in 37% and being informed on television about transplantation in 66%. In a logistic regression model, the features significantly associated with being an eventual donor were the decision of donating organs of relatives (Odds Ratio [OR] 9.1 95% confidence intervals [CI] 4.8-17-2), commenting and knowing the opinion of relatives (OR 2.3 95%CI 1.2-4.1), especially parents and partner, and a lower age (OR 0.98 95% CI 0.96-0.99). Conclusions: The decision to donate organs is influenced by commenting and knowing the opinion of relatives, especially parents and partners. Also, a lower age is associated with a better attitude towards donation.


Assuntos
Humanos , Feminino , Adulto Jovem , Obtenção de Tecidos e Órgãos , Transplante de Órgãos , Doadores de Tecidos , Chile , Características da Família , Inquéritos e Questionários
14.
Investig. andin ; 22(40)jun. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1550414

RESUMO

El uso de antibióticos en el tratamiento de la mastitis en la industria lechera ha acarreado una problemática con potencial impacto en la salud pública, como la resistencia antimicrobiana. El objetivo del presente trabajo fue evaluar la acción antimicrobiana del extracto alcohólico de hojas, tallos y flores de Tithonia diversifolia sobre el crecimiento de Staphylococcus aureus y Escherichia coli en cultivo in vitro. Se evaluó el efecto inhibitorio en el crecimiento bacteriano a través de un ensayo de sensibilidad. En ambas bacterias el control positivo presentó un halo de inhibición superior a 30 mm, con diferencia significativa de los extractos de T. diversifolia. Los cuales presentaron para S. aureus un halo de 9,7 y 10,4 mm y para E. coli de 6,5 y 9,4 mm para tallo-hoja y flores respectivamente. El extracto alcohólico de flores de T. diversifolia se perfila como una herramienta potencial para inhibir el crecimiento bacteriano.


Antibiotics used as a treatment for mastitis in the dairy industry have brought a problem with a potential impact on public health, such as antimicrobial resistance. The objective of this study is to evaluate the antimicrobial action of alcoholic extract from Tithonia diversifolia's leaves, stems, and flowers on the growth of Staphylococcus aureus and Escherichia coli in in vitro cultures. The inhibitory effect on bacterial growth was evaluated through a sensitivity test. In both bacteria, the positive control presented an inhibition halo greater than 30 mm, with a significant difference from the extracts of T. diversifolia, which presented, for S. aureus, a halo of 9.7 and 10.4 mm and for E. coli of 6.5 and 9.4 mm for stem-leaf and flowers respectively. The alcoholic extract of T. diversifolia flowers is emerging as a potential tool to inhibit bacterial growth.

15.
Langmuir ; 36(13): 3315-3322, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32167774

RESUMO

Nacre-like ceramic composites are of importance in a wide range of applications, because of their mechanical properties, combining high mechanical strength and high fracture toughness. Those mechanical properties are the result of strongly aligned platelets glued in a matrix. Different methods exist to shape such a "brick-and-mortar" hierarchical structure. In this paper, we propose to use the phenomenon of heteroaggregation between silica nanoparticles and large alumina platelets. Experimental and numerical results show that silica nanoparticles can adsorb on alumina platelets with good distribution. This adsorption promotes the deagglomeration of alumina that can self-organize in layers by sedimentation. This phenomenon can be exploited to shape alumina-silica nacre-like composites.

16.
J Endocr Soc ; 3(3): 655-664, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30842989

RESUMO

Prostate cancer (PCa) preferentially metastasizes to bone, leading to complications including severe pain, fractures, spinal cord compression, bone marrow suppression, and a mortality of ∼70%. In spite of recent advances in chemo-, hormonal, and radiation therapies, bone-metastatic, castrate-resistant PCa is incurable. PCa is somewhat unique among the solid tumors in its tendency to produce osteoblastic lesions composed of hypermineralized bone with multiple layers of poorly organized type I collagen fibrils that have reduced mechanical strength. Many of the signaling pathways that control normal bone homeostasis are at play in pathologic PCa bone metastases, including the receptor activator of nuclear factor-κB/receptor activator of nuclear factor-κB ligand/osteoprotegerin system. A number of PCa-derived soluble factors have been shown to induce the dysfunctional osteoblastic phenotype. However, therapies directed at these osteoblastic-stimulating proteins have yielded disappointing clinical results to date. One of the soluble factors expressed by PCa cells, particularly in bone metastases, is prostatic acid phosphatase (PAP). Human PAP is a prostate epithelium-specific secretory protein that was the first tumor marker ever described. Biologically, PAP exhibits both phosphatase activity and ecto-5'-nucleotidase activity, generating extracellular phosphate and adenosine as the final products. Accumulating evidence indicates that PAP plays a causal role in the osteoblastic phenotype and aberrant bone mineralization seen in bone-metastatic, castrate-resistant PCa. Targeting PAP may represent a therapeutic approach to improve morbidity and mortality from PCa osteoblastic bone metastases.

17.
Sci Rep ; 8(1): 17531, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30510210

RESUMO

Epididymal Cysteine Rich Secretory Proteins 1 and 4 (CRISP1 and CRISP4) associate with sperm during maturation and play different roles in fertilization. However, males lacking each of these molecules individually are fertile, suggesting compensatory mechanisms between these homologous proteins. Based on this, in the present work, we generated double CRISP1/CRISP4 knockout (DKO) mice and examined their reproductive phenotype. Our data showed that the simultaneous lack of the two epididymal proteins results in clear fertility defects. Interestingly, whereas most of the animals exhibited specific sperm fertilizing ability defects supportive of the role of CRISP proteins in fertilization, one third of the males showed an unexpected epididymo-orchitis phenotype with altered levels of inflammatory molecules and non-viable sperm in the epididymis. Further analysis showed that DKO mice exhibited an immature epididymal epithelium and abnormal luminal pH, supporting these defects as likely responsible for the different phenotypes observed. These observations reveal that CRISP proteins are relevant for epididymal epithelium differentiation and male fertility, contributing to a better understanding of the fine-tuning mechanisms underlying sperm maturation and immunotolerance in the epididymis with clear implications for human epididymal physiology and pathology.


Assuntos
Diferenciação Celular , Epididimo/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Glicoproteínas de Membrana/deficiência , Proteínas de Plasma Seminal/genética , Animais , Epididimo/patologia , Epitélio/metabolismo , Epitélio/patologia , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Knockout
18.
Biol Reprod ; 99(2): 373-383, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29481619

RESUMO

Epididymal sperm protein CRISP1 has the ability to both regulate murine CatSper, a key sperm calcium channel, and interact with egg-binding sites during fertilization. In spite of its relevance for sperm function, Crisp1-/-mice are fertile. Considering that phenotypes can be influenced by the genetic background, in the present work mice from the original mixed Crisp1-/- colony (129/SvEv*C57BL/6) were backcrossed onto the C57BL/6 strain for subsequent analysis of their reproductive phenotype. Whereas fertility and fertilization rates of C57BL/6 Crisp1-/- males did not differ from those reported for mice from the mixed background, several sperm functional parameters were clearly affected by the genetic background. Crisp1-/- sperm from the homogeneous background exhibited defects in both the progesterone-induced acrosome reaction and motility not observed in the mixed background, and normal rather than reduced protein tyrosine phosphorylation. Additional studies revealed a significant decrease in sperm hyperactivation as well as in cAMP and protein kinase A (PKA) substrate phosphorylation levels in sperm from both colonies. The finding that exposure of mutant sperm to a cAMP analog and phosphodiesterase inhibitor overcame the sperm functional defects observed in each colony indicated that a common cAMP-PKA signaling defect led to different phenotypes depending on the genetic background. Altogether, our observations indicate that the phenotype of CRISP1 null males is modulated by the genetic context and reveal new roles for the protein in both the functional events and signaling pathways associated to capacitation.


Assuntos
Fertilidade/genética , Fertilização/genética , Glicoproteínas de Membrana/genética , Reprodução/genética , Espermatozoides/metabolismo , Reação Acrossômica/efeitos dos fármacos , Reação Acrossômica/genética , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Patrimônio Genético , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Progesterona/farmacologia , Motilidade dos Espermatozoides/genética , Espermatozoides/efeitos dos fármacos
19.
Ultrasonics ; 84: 25-33, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29073484

RESUMO

Spray pyrolysis process has been used for the synthesis of non-oxide ceramic powders from liquid precursors in the Si/C/N system. Particles with a high thermal stability and with variable composition and size distribution have been obtained. In this process, the mechanisms involved in precursor decomposition and gas phase recombination of species are still unknown. The final aim of this work consists in improving the whole process comprehension by an experimental/modelling approach that helps to connect the synthesized particles characteristics to the precursor properties and process operating parameters. It includes the following steps: aerosol formation by a piezoelectric nebulizer, its transport and the chemical-physical phenomena involved in the reaction processes. This paper focuses on the aerosol characterization to understand the relationship between the liquid precursor properties and the liquid droplet diameter distribution. Liquids with properties close to the precursor of interest (hexamethyldisilazane) have been used. Experiments have been performed using a shadowgraphy technique to determine the drop size distribution of the aerosol. For all operating parameters of the nebulizer device and liquids used, bimodal droplet size distributions have been obtained. Correlations proposed in the literature for the droplet size prediction by ultrasonic nebulization were used and adapted to the specific nebulizer device used in this study, showing rather good agreement with experimental values.

20.
Am J Physiol Renal Physiol ; 311(4): F822-F829, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27465993

RESUMO

The mechanisms by which prostanoids contribute to the maintenance of whole body water homeostasis are complex and not fully understood. The present study demonstrates that an EP3-dependent feedback mechanism contributes to the regulation of water homeostasis under high-salt conditions. Rats on a normal diet and tap water were placed in metabolic cages and given either sulprostone (20 µg·kg-1·day-1) or vehicle for 3 days to activate EP3 receptors in the thick ascending limb (TAL). Treatment was continued for another 3 days in rats given either 1% NaCl in the drinking water or tap water. Sulprostone decreased expression of cyclooxygenase 2 (COX-2) expression by ∼75% in TAL tubules from rats given 1% NaCl concomitant with a ∼60% inhibition of COX-2-dependent PGE2 levels in the kidney. Urine volume increased after ingestion of 1% NaCl but was reduced ∼40% by sulprostone. In contrast, the highly selective EP3 receptor antagonist L-798106 (100 µg·kg-1·day-1), which increased COX-2 expression and renal PGE2 production, increased urine volume in rats given 1% NaCl. Sulprostone increased expression of aquaporin-2 (AQP2) in the inner medullary collecting duct plasma membrane in association with an increase in phosphorylation at Ser269 and decrease in Ser261 phosphorylation; antagonism of EP3 with L-798106 reduced AQP2 expression. Thus, although acute activation of EP3 by PGE2 in the TAL and collecting duct inhibits the Na-K-2Cl cotransporter and AQP2 activity, respectively, chronic activation of EP3 in vivo limits the extent of COX-2-derived PGE2 synthesis, thereby mitigating the inhibitory effects of PGE2 on these transporters and decreasing urine volume.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Retroalimentação Fisiológica/fisiologia , Rim/metabolismo , Receptores de Prostaglandina E Subtipo EP3/metabolismo , Sódio na Dieta/administração & dosagem , Água/metabolismo , Animais , Aquaporina 2/genética , Aquaporina 2/metabolismo , Ciclo-Oxigenase 2/genética , Retroalimentação Fisiológica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Masculino , Ratos , Receptores de Prostaglandina E Subtipo EP3/genética , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
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