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1.
AAPS PharmSciTech ; 22(1): 14, 2020 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-33377174

RESUMEN

Most of the commercially available pharmaceutical products for oral administration route are marketed in the tablet dosage forms. However, compression of multiparticulate systems is a challenge for the pharmaceutical research and industry, especially if the individual unit is a coated particle, as the release of the active ingredient depends on the integrity of the coating. In the present study, polymer-coated pellets tableted with different types of excipients (powder, granules, pellets) then were investigated by various tablet-destructive (microscopic) and tablet non-destructive (microfocus X-ray; microCT) imaging methods. The information obtained from the independent evaluation of the in vitro drug release profiles model is confirmed by the results obtained by image analysis, regardless of whether X-ray or stereomicroscopic images of the coated, tableted pellets were used for image analysis. The results of this study show that the novel easy-to-use, fast, and non-destructive MFX method is a good alternative to the already used microscopic image analysis methods regarding the characterization of particulates, compressed into tablets.


Asunto(s)
Química Farmacéutica/métodos , Administración Oral , Implantes de Medicamentos , Liberación de Fármacos , Excipientes , Polímeros , Polvos , Solubilidad , Comprimidos
2.
Cureus ; 15(9): e46132, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37779682

RESUMEN

INTRODUCTION AND AIM: This study aimed to evaluate the ability of fluoride-releasing adhesives to inhibit enamel demineralization surrounding orthodontic brackets. METHODS: Two groups of 40 sound human premolars were sectioned mesio-distally. The halves were varnished, and orthodontic brackets were bonded with different adhesive materials. An area 1 mm wide surrounding the brackets was left exposed. Each specimen was immersed daily in a pH cycle for 28 days. In the second group, the specimens were exposed daily to a fluoride solution (250 ppm F-) at 37°C. The fluoride release from different groups was measured. Quantitative light-induced fluorescence (QLF) was used to quantify fluorescence loss of enamel surfaces adjacent to the brackets. Results were statistically analyzed using ANOVA at (p<0.05). RESULTS: Fluoride released from the three fluoride-releasing adhesives was significantly higher (p<0.001) in the group with daily fluoride exposures than in the group without fluoride exposures. Enamel adjacent to brackets bonded with Fuji Ortho LC, Ketac Cem, and Dyract Cem showed significantly less (p<0.001) changes in (ΔQ) value (less demineralization) than enamel bonded with Transbond, the control adhesive material. CONCLUSIONS: Using fluoride-releasing adhesives significantly reduced the level of demineralization adjacent to orthodontic brackets.

3.
Colloids Surf B Biointerfaces ; 213: 112406, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35219220

RESUMEN

Mucoadhesion testing at macroscopic scale needs a robust, convenient in vitro method as ex vivo methods suffer from poor reproducibility and ethical problems. Here we synthesized mucin-free poly(vinyl alcohol) (PVA) and mucin-containing PVA hydrogel substrates (Muc/PVA) to measure adhesion of polymer tablets. Freezing-thawing method was used for gelation to avoid chemical cross-linking and to preserve the functionality of mucin. The adhesion of first generation mucoadhesive polymers, poly(acrylic acid) (PAA) and hydroxypropylmethylcellulose (HPMC) was tested with outstanding reproducibility on individual batches of hydrogels and qualitative agreement with ex vivo literature data. Negatively charged PAA was less adhesive on Muc/PVA surface than on mucin-free PVA whereas HPMC as a neutral polymer displayed similar adhesion strength on both surfaces. Chitosan as a positively charged polymer showed enhanced adhesion on Muc/PVA substrate compared to mucin-free PVA. These results are corroborated by turbidimetric titration which indicated attractive electrostatic interactions between chitosan and mucin in contrast to the lack of attractive interactions for PAA and HPMC. These results prove the role of electronic theory in macroscopic mucoadhesion.


Asunto(s)
Quitosano , Alcohol Polivinílico , Hidrogeles/química , Mucinas , Polímeros , Alcohol Polivinílico/química , Reproducibilidad de los Resultados
4.
mSphere ; 5(1)2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32024712

RESUMEN

Despite evidence of a chronic inflammatory phenotype in people living with HIV (PLWH) on antiretroviral therapy (ART), the role of oral microbiota in chronic immune activation has not been fully explored. We aimed to determine the relationship between oral and gut microbiome diversity and chronic systemic inflammation in ART-treated PLWH with prevalent severe periodontitis, an inflammatory condition commonly associated with HIV infection. We assessed bacterial and fungal communities at oral and gastrointestinal sites in a cohort (n = 52) of primarily postmenopausal women on ART using 16S rRNA and internal transcribed spacer (ITS) sequencing and measured cellular and soluble markers of inflammation and immune dysfunction. Linear mixed-effect regression and differential abundance analyses were used to associate clinical characteristics and immunological markers with bacterial and fungal diversity and community composition. Bacterial α-diversity in plaque, saliva, and gut was associated with different immunological markers, while mycobial diversity was not associated with soluble or cellular biomarkers of immune stimulation or T cell dysfunction. Furthermore, lipopolysaccharide-positive (LPS+) bacteria previously linked to inflammatory outcomes were enriched at oral sites in patients with severe periodontitis. Fungal α-diversity was reduced in plaque from teeth with higher clinical attachment loss, a marker of periodontitis, and in saliva and plaque from patients with a history of AIDS. Our results show that both bacterial and fungal oral microbiome communities likely play a role in chronic systemic immune activation in PLWH. Thus, interventions targeting both inflammation and the microbiome, particularly in the oral cavity, may be necessary to reduce chronic immune dysregulation in patients with HIV.IMPORTANCE A feedback loop between dysbiotic gut microbiota, increased translocation of microbial products such as lipopolysaccharide, and inflammation has been hypothesized to cause immune system dysfunction in early HIV infection. However, despite evidence of a chronic inflammatory phenotype in patients on antiretroviral therapy (ART), the role of oral microbiota in systemic immune activation and the relationship between oral and gut bacterial and fungal diversity have not been explored. Our study suggests a crucial role for oral bacterial and fungal communities in long-term systemic immune activation in patients on ART, expanding the current paradigm focused on gut bacteria. Our results indicate that interventions targeting both inflammation and microbial diversity are needed to mitigate oral inflammation-related comorbidities, particularly in HIV-positive patients. More broadly, these findings can bolster general models of microbiome-mediated chronic systemic immune activation and aid the development of precise microbiota-targeted interventions to reverse chronic inflammation.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Microbioma Gastrointestinal , Infecciones por VIH/tratamiento farmacológico , Micobioma , Bacterias/clasificación , Femenino , Humanos , Factores Inmunológicos , Inflamación/microbiología , Modelos Lineales , Persona de Mediana Edad , Posmenopausia , ARN Ribosómico 16S/genética , Saliva/microbiología
5.
Artículo en Inglés | MEDLINE | ID: mdl-31221613

RESUMEN

OBJECTIVES: The purpose of this European multicenter prospective study was to obtain more precise information about the demographic characteristics and etiologic/epidemiologic patterns of motor vehicle accidents (MVA)-related maxillofacial fractures. STUDY DESIGN: Of the 3260 patients with maxillofacial fractures admitted within the study period, 326 traumas were caused by MVAs with a male/female ratio of 2.2:1. RESULTS: The maximum incidence was found in Zagreb (Croatia) (18%) and the minimum in Bergen (Norway) (0%). The most frequent mechanisms were car accidents, with 177 cases, followed by motorcycle accidents. The most frequently observed fracture involved the mandible, with 199 fractures, followed by maxillo-zygomatic-orbital (MZO) fractures. CONCLUSIONS: In all the 3 groups (car, motorcycle, and pedestrian), mandibular and MZO fractures were the 2 most frequently observed fractures, with some variations. The importance of analyzing MVA-related facial injuries and their features and characteristics should be stressed.


Asunto(s)
Fracturas Mandibulares , Traumatismos Maxilofaciales , Fracturas Craneales , Fracturas Cigomáticas , Accidentes de Tránsito , Femenino , Humanos , Masculino , Vehículos a Motor , Noruega , Estudios Prospectivos , Estudios Retrospectivos
6.
J Craniomaxillofac Surg ; 43(1): 62-70, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25457465

RESUMEN

The purpose of this study was to analyse the demographics, causes and characteristics of maxillofacial fractures managed at several European departments of oral and maxillofacial surgery over one year. The following data were recorded: gender, age, aetiology, site of facial fractures, facial injury severity score, timing of intervention, length of hospital stay. Data for a total of 3396 patients (2655 males and 741 females) with 4155 fractures were recorded. The mean age differed from country to country, ranging between 29.9 and 43.9 years. Overall, the most frequent cause of injury was assault, which accounted for the injuries of 1309 patients; assaults and falls alternated as the most important aetiological factor in the various centres. The most frequently observed fracture involved the mandible with 1743 fractures, followed by orbital-zygomatic-maxillary (OZM) fractures. Condylar fractures were the most commonly observed mandibular fracture. The results of the EURMAT collaboration confirm the changing trend in maxillofacial trauma epidemiology in Europe, with trauma cases caused by assaults and falls now outnumbering those due to road traffic accidents. The progressive ageing of the European population, in addition to strict road and work legislation may have been responsible for this change. Men are still the most frequent victims of maxillofacial injuries.


Asunto(s)
Traumatismos Maxilofaciales/epidemiología , Fracturas Craneales/epidemiología , Accidentes por Caídas/estadística & datos numéricos , Accidentes de Tránsito/estadística & datos numéricos , Adulto , Factores de Edad , Traumatismos en Atletas/epidemiología , Europa (Continente)/epidemiología , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Tiempo de Internación/estadística & datos numéricos , Masculino , Cóndilo Mandibular/lesiones , Fracturas Mandibulares/epidemiología , Fracturas Maxilares/epidemiología , Persona de Mediana Edad , Traumatismos Ocupacionales/epidemiología , Fracturas Orbitales/epidemiología , Estudios Prospectivos , Estaciones del Año , Factores Sexuales , Violencia/estadística & datos numéricos , Fracturas Cigomáticas/epidemiología
7.
Artículo en Inglés | MEDLINE | ID: mdl-25640305

RESUMEN

OBJECTIVE: The aim of this study is to present and discuss the demographic characteristics and patterns of assault-related maxillofacial fractures as reported by a European multicenter prospective study. STUDY DESIGN: Demographic and injury data were recorded for each patient who was a victim of an assault. RESULTS: Assaults represented the most frequent etiology of maxillofacial trauma with an overall rate of 39% and the values ranging between 60.8% (Kiev, Ukraine) and 15.4% (Bergen, Norway). The most frequent mechanisms of assault-related maxillofacial fractures were fists in 730 cases, followed by kicks and fists. The most frequently observed fracture involved the mandible (814 fractures), followed by orbito-zygomatic-maxillary complex fractures and orbital fractures. CONCLUSIONS: Our data confirmed the strong possibility that patients with maxillofacial fractures may be victims of physical aggression. The crucial role of alcohol in assault-related fractures was also confirmed by our study.


Asunto(s)
Fracturas Óseas/epidemiología , Traumatismos Maxilofaciales/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Conducta Cooperativa , Demografía , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
8.
Artículo en Inglés | MEDLINE | ID: mdl-25660086

RESUMEN

OBJECTIVE: The aim of this study is to present and discuss the results of a European multicentre prospective study about pediatric maxillofacial trauma epidemiology during a year. STUDY DESIGN: The following data were recorded: gender, age, etiology, site of fracture, date of injury. Of the 3396 patients with maxillofacial fractures admitted within the study period, 114 (3.3%) were children aged 15 years and younger, with a male/female ratio of 2.6:1. Mean age was 10.9 years. Most patients (63%) were aged 11-15 years. RESULTS: The most frequent cause of injury was fall (36 patients). Sport injuries and assaults were almost limited to the oldest group, whereas falls were more uniformly distributed in the 3 groups. The most frequently observed fracture involved the mandible with 47 fractures. In particular, 18 condylar fractures were recorded, followed by 12 body fractures. CONCLUSIONS: Falls can be acknowledged as the most important cause of facial trauma during the first years of life. The high incidence of sport accidents after 10 years may be a reason to increase the use of mouthguards and other protective equipment. Finally, the mandible (and in particular the condyle) was confirmed as the most frequent fracture site.


Asunto(s)
Traumatismos Maxilofaciales/epidemiología , Accidentes por Caídas/estadística & datos numéricos , Adolescente , Traumatismos en Atletas/epidemiología , Traumatismos en Atletas/terapia , Niño , Preescolar , Europa (Continente)/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Traumatismos Maxilofaciales/terapia , Estudios Prospectivos , Factores de Riesgo , Estaciones del Año
10.
Am J Orthod Dentofacial Orthop ; 123(5): 534-9, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12750672

RESUMEN

The aim of this study was to identify the presence and pattern of differences in bond failure between tooth types in vivo when bonding orthodontic brackets with the no-mix orthodontic composite adhesive Right-On. In vivo bond failure for a single operator was recorded for 108 consecutive patients undergoing fixed-appliance orthodontic treatment. The bond failure data were analyzed by survival analysis. Time to first failure or censorship was recorded for each bonded attachment. Overall failure in the sample matched previous clinical studies but conflicted with previous ex vivo bond strength data. Mandibular and posterior teeth had significantly higher rates of failure than did maxillary and anterior teeth. The type of attachment used had a significant effect on bond survival. The results of this study confirm that in vivo bond survival is not uniform for all teeth. Comparisons between the findings of this study and those of a previous ex vivo study by the same authors failed to validate ex vivo bond strength testing as clinically relevant.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Recubrimientos Dentinarios , Femenino , Humanos , Masculino , Diseño de Aparato Ortodóncico , Estudios Prospectivos , Cementos de Resina , Análisis de Supervivencia , Diente
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