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1.
ACS Omega ; 9(9): 10539-10555, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463280

RESUMO

Covarine, copper phthalocyanine, a novel tooth whitening ingredient, has been incorporated into various toothpaste formulations using diverse technologies such as larger flakes, two-phase pastes, and microbeads. In this study, we investigated the behavior of covarine microbeads (200 µm) in Colgate advanced white toothpaste when mixed with artificial and real saliva. Our analysis utilized a custom-designed microfluidic mixer with 400 µm wide channels arranged in serpentine patterns, featuring a Y-shaped design for saliva and toothpaste flow. The mixer, fabricated using stereolithography 3D printing technology, incorporated a flexible transparent resin (Formlabs' Flexible 80A resin) and PMMA layers. COMSOL simulations were performed by utilizing parameters extracted from toothpaste and saliva datasheets, supplemented by laboratory measurements, to enhance simulation accuracy. Experimental assessments encompassing the behavior of covarine particles were conducted using an optical profilometer. Viscosity tests and electrical impedance spectroscopy employing recently developed all-carbon electrodes were employed to analyze different toothpaste dilutions. The integration of experimental data from microfluidic chips with computational simulations offers thorough insights into the interactions of covarine particles with saliva and the formation of microfilms on enamel surfaces.

2.
J Oral Sci ; 66(1): 60-65, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38233156

RESUMO

PURPOSE: To investigate the surface topography and nickel content of nickel-titanium (NiTi) archwires exposed to either routine oral hygiene or a prophylactic regimen with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) during orthodontic treatment. METHODS: This in vivo study involved 40 orthodontic patients with fixed appliances, who were randomly assigned to either a routine oral hygiene group or a CPP-ACP supplementary regimen group. Twenty new NiTi archwires served as controls. All archwires underwent scanning electron microscopy and energy-dispersive spectroscopy to evaluate their surface topography and elemental composition. The nickel content was quantified as a percentage of total weight and the Ni/Ti ratio, and statistical comparisons were made using pairwise tests. RESULTS: Wires exposed to fluoride toothpaste showed signs of pitting corrosion, deep grooves, and corrosion debris. In contrast, wires exposed to supplementary CPP-ACP exhibited smooth surface areas interspersed with microdefects and deposits. Statistically significant differences in nickel content were found between the new and retrieved archwires, as well as between wires exposed to routine oral hygiene and CPP-ACP (P < 0.001). The archwires exposed to CPP-ACP had the lowest nickel content (P < 0.001). CONCLUSION: The use of CPP-ACP holds promise for application as a safe anticariogenic agent with possible protective properties during orthodontic treatment.


Assuntos
Fosfatos de Cálcio , Caseínas , Fosfopeptídeos , Humanos , Níquel/química , Titânio/química , Ligas Dentárias/química , Aparelhos Ortodônticos Fixos , Propriedades de Superfície , Teste de Materiais
3.
Sci Rep ; 13(1): 21277, 2023 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042878

RESUMO

Intraoral theranostics, the integration of diagnostics and therapeutics within the oral cavity, is gaining significant traction. This pioneering approach primarily addresses issues like xerostomia (dry mouth), commonly resulting from cancer treatment, with a specific focus on monitoring temperature and humidity. This paper introduces the innovative Intra-Oral Portable Micro-Electronic (IOPM) fluidic theranostic device platform. It leverages conventional dental spoons by incorporating advanced sensors for precise measurements of oral temperature and humidity. Personalization options include a microfluidic chip and a tooth model, enabling targeted delivery of therapeutic agents to optimize treatment outcomes. The electronic control system simplifies the administration of fluid dosages, intelligently adjusted based on real-time oral cavity temperature and humidity readings. Rigorous experimental evaluations validate the platform's precision in delivering fluid volumes at predefined intervals. This platform represents a transformative advancement for individuals contending with oral health challenges such as xerostomia (dry mouth). Furthermore, it has the potential to elevate oral healthcare standards by providing advanced diagnostics and tailored therapeutic solutions, benefiting both patients and dental professionals alike.


Assuntos
Xerostomia , Humanos , Temperatura , Umidade , Xerostomia/diagnóstico , Xerostomia/terapia , Exame Físico
4.
Front Public Health ; 11: 1279915, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927882

RESUMO

This systematic review and meta-analysis aimed to evaluate the ingestion of toothpaste and its sequelae. The study adhered to the PRISMA guidelines and was registered in the PROSPERO database. A comprehensive search strategy was conducted across multiple databases, resulting in the inclusion of 18 relevant publications. Eligible studies encompassed various designs and included both children and adults as the study population. Data extraction was carried out systematically, and relevant information on study characteristics, interventions, and outcomes were collected. The assessment of bias was performed using the Joanna Briggs Institute's Critical Appraisal Tools showing variations of bias among the included studies. The overall risk of systemic toxicity was found to be low, and no severe or life-threatening events were reported in the included studies. Furthermore, some toothpaste formulations containing higher concentrations of fluoride were associated with an increased risk of dental fluorosis. These findings have several implications for practice and policy. Healthcare providers and dental professionals should emphasize the importance of promoting safe toothpaste use, especially in vulnerable populations such as young children who are more prone to accidental ingestion. Public health campaigns and educational initiatives should aim to raise awareness about appropriate toothpaste usage and the potential risks. In addition, toothpaste manufacturers and regulatory bodies should consider revising guidelines and regulations to ensure the safety of oral care products, including the appropriate concentration of active ingredients. Future research should focus on investigating the long-term effects of toothpaste ingestion, exploring potential interactions between different active ingredients, and evaluating the efficacy of current preventive measures.


Assuntos
Fluoretos , Cremes Dentais , Criança , Adulto , Humanos , Pré-Escolar , Cremes Dentais/efeitos adversos , Fluoretos/efeitos adversos , Promoção da Saúde , Pessoal de Saúde , Ingestão de Alimentos
5.
Micromachines (Basel) ; 14(3)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36984909

RESUMO

The connection of macrosystems with microsystems for in-line measurements is important in different biotechnological processes as it enables precise and accurate monitoring of process parameters at a small scale, which can provide valuable insights into the process, and ultimately lead to improved process control and optimization. Additionally, it allows continuous monitoring without the need for manual sampling and analysis, leading to more efficient and cost-effective production. In this paper, a 3D printed microfluidic (MF) chip for glucose (Glc) sensing in a liquid analyte is proposed. The chip made in Poly(methyl methacrylate) (PMMA) contains integrated serpentine-based micromixers realized via stereolithography with a slot for USB-like integration of commercial DropSens electrodes. After adjusting the sample's pH in the first micromixer, small volumes of the sample and enzyme are mixed in the second micromixer and lead to a sensing chamber where the Glc concentration is measured via chronoamperometry. The sensing potential was examined for Glc concentrations in acetate buffer in the range of 0.1-100 mg/mL and afterward tested for Glc sensing in a cell culturing medium. The proposed chip showed great potential for connection with macrosystems, such as bioreactors, for direct in-line monitoring of a quality parameter in a liquid sample.

6.
PLoS One ; 18(2): e0280381, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36795661

RESUMO

Diagnosing oral diseases at an early stage may lead to better preventive treatments, thus reducing treatment burden and costs. This paper introduces a systematic design of a microfluidic compact disc (CD) consisting of six unique chambers that run simultaneously from sample loading, holding, mixing and analysis. In this study, the electrochemical property changes between real saliva and artificial saliva mixed with three different types of mouthwashes (i.e. chlorhexidine-, fluoride- and essential oil (Listerine)-based mouthwashes) were investigated using electrical impedance analysis. Given the diversity and complexity of patient's salivary samples, we investigated the electrochemical impedance property of healthy real saliva mixed with different types of mouthwashes to understand the different electrochemical property which could be a foundation for diagnosis and monitoring of oral diseases. On the other hand, electrochemical impedance property of artificial saliva, a commonly used moisturizing agent and lubricant for the treatment of xerostomia or dry mouth syndrome was also studied. The findings indicate that artificial saliva and fluoride-based mouthwash showed higher conductance values compared to real saliva and two other different types of mouthwashes. The ability of our new microfluidic CD platform to perform multiplex processes and detection of electrochemical property of different types of saliva and mouthwashes is a fundamental concept for future research on salivary theranostics using point-of-care microfluidic CD platform.


Assuntos
Antissépticos Bucais , Xerostomia , Humanos , Saliva Artificial/química , Impedância Elétrica , Fluoretos/análise , Microfluídica , Clorexidina , Saliva/química , Xerostomia/terapia
7.
Colloids Surf B Biointerfaces ; 222: 113014, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427407

RESUMO

Deoxycholic acid (DCA) is a bile acid capable of forming micelles and modifying the properties of hydrogels. We incorporated DCA in sodium alginate (SA) and poloxamer 407 matrices creating novel DCA-copolymer hydrogel for therapeutic delivery. Hydrogels were assessed for common rheological properties. Biocompatibility and biological effect were examined on various cell lines. Cell viability was determent in normal and various hypoxic conditions, and full mitochondrial bioenergetic parameters were assessed in cell lines in order to illustrate hydrogel effects on survival, and cell metabolic profile within the hydrogels. Obtained data suggest that a low dose of DCA in permeable, biocompatible hydrogels can be beneficial for cells to combat hypoxic conditions.


Assuntos
Hidrogéis , Micelas , Hidrogéis/farmacologia , Linhagem Celular , Alginatos/farmacologia , Poloxâmero
8.
Biosensors (Basel) ; 12(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36551136

RESUMO

Drug delivery systems are engineered platforms for the controlled release of various therapeutic agents. This paper presents a conductive gold leaf-based microfluidic platform fabricated using xurography technique for its potential implication in controlled drug delivery operations. To demonstrate this, peppermint and eucalyptus essential oils (EOs) were selected as target fluids, which are best known for their medicinal properties in the field of dentistry. The work takes advantage of the high conductivity of the gold leaf, and thus, the response characteristics of the microfluidic chip are studied using electrochemical impedance spectroscopy (EIS) upon injecting EOs into its micro-channels. The effect of the exposure time of the chip to different concentrations (1% and 5%) of EOs was analyzed, and change in electrical resistance was measured at different time intervals of 0 h (the time of injection), 22 h, and 46 h. It was observed that our fabricated device demonstrated higher values of electrical resistance when exposed to EOs for longer times. Moreover, eucalyptus oil had stronger degradable effects on the chip, which resulted in higher electrical resistance than that of peppermint. 1% and 5% of Eucalyptus oil showed an electrical resistance of 1.79 kΩ and 1.45 kΩ at 10 kHz, while 1% and 5% of peppermint oil showed 1.26 kΩ and 1.07 kΩ of electrical resistance at 10 kHz respectively. The findings obtained in this paper are beneficial for designing suitable microfluidic devices to expand their applications for various biomedical purposes.


Assuntos
Óleos Voláteis , Óleos Voláteis/química , Óleo de Eucalipto , Espectroscopia Dielétrica , Ouro , Microfluídica , Folhas de Planta
9.
Materials (Basel) ; 15(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500200

RESUMO

Nitinol (NiTi) alloy is a widely used material for the production of orthodontic archwires. Its corrosion behavior in conditions that exist in the oral cavity still remains a great characterization challenge. The motivation behind this work is to reveal the influence of commercially available mouthwashes on NiTi orthodontic archwires by performing non-electrochemical corrosion tests and quantifying the changes in the nanotopography of commercially available NiTi orthodontic wires. In this study, we examined the behavior of NiTi alloy archwires exposed for 21.5 days to different corrosive media: artificial saliva, Eludril®, Aquafresh®, and Listerine®. The corrosion was characterized by contact mode atomic force microscopy (AFM) before and after the corrosion tests. A novel analysis methodology was developed to obtain insight into locations of material gain or material loss based on standard surface roughness parameters Sa, Sdr, Ssk, and S10z. The developed methodology revealed that fluoride-containing mouthwashes (Aquafresh® and Listerine®) dominantly cause material loss, while chloride-containing mouthwash (Eludril®) can cause both material loss and material gain. The sample exposed to artificial saliva did not display significant changes in any parameter.

10.
Nanomaterials (Basel) ; 12(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432311

RESUMO

bioNEMS/MEMS has emerged as an innovative technology for the miniaturisation of biomedical devices with high precision and rapid processing since its first R&D breakthrough in the 1980s. To date, several organic including food waste derived nanomaterials and inorganic nanomaterials (e.g., carbon nanotubes, graphene, silica, gold, and magnetic nanoparticles) have steered the development of high-throughput and sensitive bioNEMS/MEMS-based biosensors, actuator systems, drug delivery systems and implantable/wearable sensors with desirable biomedical properties. Turning food waste into valuable nanomaterials is potential groundbreaking research in this growing field of bioMEMS/NEMS. This review aspires to communicate recent progress in organic and inorganic nanomaterials based bioNEMS/MEMS for biomedical applications, comprehensively discussing nanomaterials criteria and their prospects as ideal tools for biomedical devices. We discuss clinical applications for diagnostic, monitoring, and therapeutic applications as well as the technological potential for cell manipulation (i.e., sorting, separation, and patterning technology). In addition, current in vitro and in vivo assessments of promising nanomaterials-based biomedical devices will be discussed in this review. Finally, this review also looked at the most recent state-of-the-art knowledge on Internet of Things (IoT) applications such as nanosensors, nanoantennas, nanoprocessors, and nanobattery.

11.
Front Pediatr ; 10: 969372, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120658

RESUMO

Introduction: One of the most common oral diseases affecting children is early childhood caries (ECC). The link between oxidative stress and ECC has been proven in numerous clinical studies. Technical and biological variability were so high in most of the studies that none of the markers have yet been proven suitable for routine clinical use. This study aimed to evaluate the antioxidant status and the levels of leptin and adiponectin in saliva of children with severe early childhood caries (S-ECC). Methods: Morning unstimulated saliva samples were collected from children (n = 40, 0-6 years old) for the evaluation of oxidative stress which were measured by total antioxidant capacity (TAC), and by the ferric reducing antioxidant power (FRAP) assays, as well as to assess the salivary levels of leptin and adiponectin. FRAP, TAC, leptin and adiponectin concentrations were evaluated in S-ECC group (n = 31) and caries free group CF (n = 9). All results were analyzed based on age and sex. Results: Overall median salivary leptin and adiponectin levels were 5.59 pg/mL and 24.86 ng/mL, respectively. Significantly lower leptin levels were observed in saliva of caries free children (4.66 pg/mL) than in the S-ECC group (6.64 pg/mL, p < 0.01). No significant difference was observed for adiponectin levels (S-ECC and CF, 25.31 and 23.2 ng/mL, respectively, p = 0.961). TAC and FRAP values of saliva had similar values in children with S-ECC and caries free children. TAC and FRAP values also remained stable with the age of the children, without significant differences with respect to sex. Conclusion: The increased concentrations of leptin in saliva of children with S-ECC suggests that leptin may play a role in inflammatory and immune responses in the development of early childhood caries.

12.
Materials (Basel) ; 15(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806590

RESUMO

Polycrystalline samples of NaCo2-xCuxO4 (x = 0, 0.01, 0.03, 0.05) were obtained from powder precursors synthesized by a mechanochemically assisted solid-state reaction method (MASSR) and a citric acid complex method (CAC). Ceramic samples were prepared by pressing into disc-shaped pellets and subsequently sintering at 880 °C in an argon atmosphere. Effects of low concentrations of Cu doping and the above-mentioned synthesis procedures on the thermoelectric and mechanical properties were observed. The electrical resistivity (ρ), the thermal conductivity (κ) and the Seebeck coefficient (S) were measured simultaneously in the temperature gradient (ΔT) between the hot and cold side of the sample, and the figure of merit (ZT) was subsequently calculated. The ZT of the CAC samples was higher compared with the MASSR samples. The highest ZT value of 0.061 at ΔT = 473 K was obtained for the sample with 5 mol% of Cu prepared by the CAC method. The CAC samples showed better mechanical properties compared to the MASSR samples due to the higher hardness of the CAC samples which is a consequence of homogeneous microstructure and higher density obtained during sintering of these samples. The results confirmed that, besides the concentration of Cu, the synthesis procedure considerably affected the thermoelectric and mechanical properties of NaCo2O4 (NCO) ceramics.

13.
Materials (Basel) ; 15(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35806658

RESUMO

The aim of this study was to tackle the topic of appropriate recommendations for artificial-saliva and mouthwash usage. The contact angle, pH, and conductivity of two artificial saliva solutions, four mouthwashes, and their mixtures on enamel, glass-ionomer, and composite dental materials were measured. The measurements were conducted with a MATLAB algorithm to minimize human error. The obtained values for the contact angle were in the range from 7.98° to 52.6°, and they showed completely nonlinear and nonuniform behavior for all investigated liquids and on all investigated substrates. Results reveal statistically significant differences among all tested liquids on all investigated substrates (p < 0.05). pH values ranged from 1.54 to 7.01. A wide range of conductivity values were observed, from 1205µS/cm in the saliva-stimulating solution to 6679 mS/cm in the artificial saliva. Spearman's test showed a moderate positive correlation between the pH and conductivity of the tested fluids (R = 0.7108). A comparison of the data obtained using Image J software and the MATLAB algorithm showed consistency, not exceeding 5% error. When an experiment uses human material and bioactive materials THAT are used in biomedicine as substrates, an additional definition of protocols is highly recommended for future research on this topic.

14.
Materials (Basel) ; 15(4)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35208062

RESUMO

Dental floss is an oral hygiene product used to remove food and plaque in places where toothbrushes cannot reach. Even though over the years since its introduction some research in suitable materials has been performed, thread cracking and wear can still compromise efficiency. The aim of this study was to examine the morphological properties of four different commercially available dental floss types before and after use. For that purpose, scanning electron microscopy and optical microscopy were used to assess the flosses before and after use, and tension testing was performed to determine any degradation in the floss performance after utilization. The analyzed floss samples verify the hypothesis that the properties of the floss need to be known in depth, before recommending a specific type to patients for daily use in all clinical indications.

15.
Biomedicines ; 10(1)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35052790

RESUMO

A recent study showed an association between diabetes development and the bile acid lithocholic acid (LCA), while another study demonstrated positive biological effects of the conjugated bile acid, taurocholic acid (TCA), on pancreatic cells. Thus, this study aimed to encapsulate TCA with primary islets (graft) and study the biological effects of the graft, post-transplantation, in diabetic mice, including effects on LCA concentrations. Sixteen mature adult mice were made diabetic and randomly divided into two equal groups, control and test (transplanted encapsulated islets without or with TCA). Graft pharmaceutical features pre-transplantation, and biological effects including on LCA concentrations post-transplantation, were measured. TCA-microcapsules had an oval shape and similar size compared with the control. The treatment group survived longer, showed improved glucose and interleukin-6 concentrations, and lower LCA concentrations in plasma, large intestine, faeces, liver and spleen, compared with control. Results suggest that TCA incorporation with islets encapsulated graft exerted beneficial effects, but there was no direct and significant dependency between concentrations of interleukin-6 and LCA.

16.
Curr Diabetes Rev ; 18(1): e062620183199, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32589561

RESUMO

AIM: Examine bile acids effects in Type 2 diabetes. BACKGROUND: In recent studies, the bile acid ursodeoxycholic acid (UDCA) has shown potent antiinflammatory effects in obese patients while in type 2 diabetics (T2D) levels of the pro-inflammatory bile acid lithocholic acid were increased, and levels of the anti-inflammatory bile acid chenodeoxycholic acid were decreased, in plasma. OBJECTIVE: Hence, this study aimed to examine applications of novel UDCA microparticles in diabetes. METHODS: Diabetic balb/c adult mice were divided into three equal groups and gavaged daily with either empty microcapsules, free UDCA, or microencapsulated UDCA over two weeks. Their blood, tissues, urine, and faeces were collected for blood glucose, inflammation, and bile acid analyses. UDCA resulted in modulatory effects on bile acids profile without antidiabetic effects suggesting that bile acid modulation was not directly linked to diabetes treatment. RESULTS: UDCA resulted in modulatory effects on bile acids profile without antidiabetic effects suggesting that bile acid modulation was not directly linked to diabetes treatment. CONCLUSION: Bile acids modulated the bile profile without affecting blood glucose levels.


Assuntos
Ácidos e Sais Biliares , Diabetes Mellitus Tipo 2 , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ácido Ursodesoxicólico/farmacologia
17.
Pharmaceutics ; 13(10)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34684006

RESUMO

INTRODUCTION: Several studies have shown that different biomaterials and hydrogels comprising various bile acids such as chenodeoxycholic acid (CDCA), as well as excipients such as poly-(styrene)-sulphonate (PSS) and poly-(allyl)-amine (PAA), exhibited positive biological effects on encapsulated viable pancreatic ß-cells. Hence, this study aimed to investigate whether incorporating CDCA with PSS and PAA will optimise the functions of encapsulated pancreatic islets post-transplantation in Type 1 diabetes (T1D). METHODS: Mice were made T1D, divided into two equal groups, and transplanted with encapsulated islets in PSS-PAA (control) or with CDCA-PSS-PAA (treatment) microcapsules. The effects of transplanted microcapsules on blood glucose, inflammation and the bile acid profile were measured post-transplantation. RESULTS AND CONCLUSION: Compared with control, the treatment group showed better survival rate, improved glycaemic control, and lower inflammatory profile, illustrated by ↓ interleukin 1-ß, interleukin-6, interleukin-12, and tumour-necrosis factor-α, and ↓ levels of the bile acid, as well as lithocholic acid in the plasma, liver, large intestine and faeces. The results suggest that CDCA incorporation with PSS-PAA microcapsules exerted beneficial effects on encapsulated islets and resulted in enhanced diabetes treatment, post-transplantation, at the local and systemic levels.

18.
Int. j. morphol ; 39(3): 780-784, jun. 2021. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1385417

RESUMO

SUMMARY: The aim of the present study was to investigate the possibility of estimating crown formation times of immature deciduous teeth and age at death in Neolithic newborns. In the Neolithic-Mesolithic transition, the health of the population deteriorated. Leaving the intrauterine environment for the newborn is the first obstacle in the process of adaptation and survival in the outside world. The fetus is protected by the mother's immune system and receives the necessary nutrients through the umbilical cord, but external factors indirectly affect its development. At birth deciduous teeth are not fully formed and are only partially mineralized. Variations in the rhythmic activity of ameloblasts and the secretion of the enamel matrix lead to the formation of incremental lines in the enamel. The sample consisted of unerupted deciduous teeth removed from the baby jaws from Neolithic archaeological graves, LepenskiVir Serbia. The skeletal age of the babies was from 38 to 40 gestational weeks. The daily enamel apposition rate was obtained for each tooth. The age of individuals was estimated using crown formation time. The average value of daily secretion rates for the primary teeth from the Neolithic age was 3.78 µm. There was no statistically significant difference in age at death determined by skeletal age assessment and crown formation time. Three babies were born preterm. The results of the present study show that the calculation of the time required for the formation of deciduous tooth enamel is applicable to archaeological samples of newborns.The age estimation using crown formation time together with the analysis of other anthropological parameters, can contribute to a more accurate determination of neonatal death in anthropological, archaeological and forensic contexts.


RESUMEN: El objetivo del estudio fue investigar la posibilidad de estimar el tiempo de formación de la corona de los dientes deciduos inmaduros y la edad, al momento de la muerte en neonatos neolíticos. Durante la transición Neolítico-Mesolítico, la salud de la población deterioró significativamente. Para el recién nacido dejar el medio intrauterino es el primer obstáculo en el proceso de adaptación y supervivencia en el mundo exterior. El feto está protegido por el sistema inmunológico de la madre y recibe los nutrientes necesarios a través del cordón umbilical, pero factores externos afectan indirectamente su desarrollo. Al nacer, los dientes deciduos no están completamente formados y solo están parcialmente mineralizados. Las variaciones en la actividad rítmica de los ameloblastos y la secreción de la matriz del esmalte conducen a la formación de líneas incrementales en el esmalte. La muestra consistió en dientes sin erupción extraídos de las mandíbulas de neonatos de tumbas arqueológicas neolíticas, LepenskiVir Serbia. La edad esquelética de los bebés fue de 38 a 40 semanas de gestación. Se obtuvo la tasa diaria de aposición de esmalte para cada diente. La edad de los individuos se estimó utilizando el tiempo de formación de la copa. El valor promedio de las tasas de secreción diaria para los dientes temporales del Neolítico fue de 3,78µm. No hubo diferencia estadísticamente significativa en la edad al momento de la muerte determinada por la evaluación de la edad esquelética y el tiempo de formación de la corona. Tres bebés nacieron prematuros. Los resultados del presente estudio muestran que el cálculo del tiempo requerido para la formación del esmalte dental deciduo es aplicable a muestras arqueológicas de recién nacidos. La estimación de la edad utilizando el tiempo de formación de la corona junto con el análisis de otros parámetros antropológicos, puede contribuir a una mayor determinación precisa de la muerte neonatal en contextos antropológicos, arqueológicos y forenses.


Assuntos
Humanos , Recém-Nascido , Dente Decíduo/crescimento & desenvolvimento , Determinação da Idade pelos Dentes , Coroa do Dente/crescimento & desenvolvimento , Esmalte Dentário/crescimento & desenvolvimento , Fatores de Tempo , Antropologia Forense , Morte Perinatal
19.
Pharmaceutics ; 12(8)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751051

RESUMO

Bile acids have recently been studied for potential applications as formulation excipients and enhancers for drug release; however, some bile acids are not suitable for this application. Unconjugated lithocholic acid (ULCA) has recently shown drug formulation-stabilizing and anti-inflammatory effects. Lipophilic drugs have poor gut absorption after an oral dose, which necessitates the administration of high doses and causes subsequent side effects. Probucol (PB) is a highly lipophilic drug with poor oral absorption that resulted in restrictions on its clinical prescribing. Hence, this study aimed to design new delivery systems for PB using ULCA-based matrices and to test drug formulation, release, temperature, and biological effects. ULCA-based matrices were formulated for PB oral delivery by applying the jet-flow microencapsulation technique using sodium alginate as a polymer. ULCA addition to new PB matrices improved the microcapsule's stability, drug release in vitro (formulation study), and showed a promising effect in ex vivo study (p < 0.05), suggesting that ULCA can optimize the oral delivery of PB and support its potential application in diabetes treatment.

20.
Expert Opin Drug Deliv ; 17(10): 1361-1376, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32597249

RESUMO

INTRODUCTION: Oral delivery is the most common administrated drug delivery path. However, oral administration of lipophilic drugs has some limitations: they have poor dose-response due to low and varied dissolution kinetics and oral bioavailability with sub-optimal dissolution within the aqueous gastrointestinal microenvironment. Therefore, there is a need for robust formulating methods that protect the drug until it reaches to its optimum absorption site, allowing its optimum pharmacological effects via increasing its intestinal permeation and bioavailability. AREA COVERED: Herein, we provide insights on orally administered lipophilic drug delivery systems. The detailed description of the obstacles associated with the oral bioavailability of lipophilic drugs are also discussed. Following this, techniques to overcome these obstacles with much emphasis on optimal safety and efficacy are addressed. Newly designed ionic vibrational jet flow encapsulation technology has enormous growth in lipophilic drug delivery systems, which is discussed thereafter. EXPERT OPINION: Researchers have shown interest in drug's encapsulation. A combination of drug-bile acid and microencapsulation methods can be one promising strategy to improve the oral delivery of lipophilic drugs. However, the most critical aspect of this approach is the selection of bile acids, polymer, and encapsulation technology.


Assuntos
Alginatos/química , Sistemas de Liberação de Medicamentos , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Animais , Disponibilidade Biológica , Humanos , Polímeros/química , Tecnologia
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