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1.
Eur Heart J Cardiovasc Imaging ; 25(6): 795-803, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38198413

RESUMEN

AIMS: Depending on volume status, secondary tricuspid regurgitation (sTR) has a strong dynamic component. In contrast, associated structural dilatation of the tricuspid annulus and the right heart chambers may be less volume dependent. This study aimed to assess the prognostic value of right heart remodelling in isolated severe sTR (isoTR). METHODS AND RESULTS: A total of 36 000 patients from the longitudinal echocardiographic database of our tertiary centre were screened for severe isoTR [vena contracta (VC) ≥ 7 mm] in the absence of atrial fibrillation (AF), other valve disease, and/or reduced systolic left ventricular function. Echocardiographic examinations were re-read, focusing on right ventricular (RV) parameters and on quantitative and qualitative parameters of isoTR. All-cause mortality was defined as the primary endpoint. Two hundred and sixteen patients fulfilled the inclusion criteria. Severe TR was predominant; only few were classified in the new grades massive [n = 23 (10%)] and torrential TR [n = 4 (2%)]. During a median follow-up of 35 months (20-53), all-cause mortality was 31% (n = 67). Multivariate Cox regression analysis revealed no association of VC, effective regurgitant orifice area, or regurgitant volume with all-cause mortality. However, indexed RV end-diastolic diameter (P < 0.001), indexed right atrial dimensions (P = 0.019), and particularly tricuspid valve (TV) annulus diameter diastole index (P = 0.002) and TV annulus diameter systole index (P = 0.001) were significantly associated with outcome. CONCLUSION: Severe isolated TR in the absence of AF is a rare finding with a grim prognosis. Tricuspid annular diameter dimensions rather than quantitative measures of TR proved to be of significant prognostic value indicating a continuous remodelling leading to a 'point of no return' with a dismal outcome.


Asunto(s)
Ecocardiografía , Sistema de Registros , Índice de Severidad de la Enfermedad , Insuficiencia de la Válvula Tricúspide , Remodelación Ventricular , Humanos , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Ecocardiografía/métodos , Pronóstico , Remodelación Ventricular/fisiología , Estudios Retrospectivos , Medición de Riesgo , Valor Predictivo de las Pruebas , Válvula Tricúspide/diagnóstico por imagen
2.
Int J Biometeorol ; 68(4): 761-775, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38285109

RESUMEN

Whereas temporal variability of plant phenology in response to climate change has already been well studied, the spatial variability of phenology is not well understood. Given that phenological shifts may affect biotic interactions, there is a need to investigate how the variability in environmental factors relates to the spatial variability in herbaceous species' phenology by at the same time considering their functional traits to predict their general and species-specific responses to future climate change. In this project, we analysed phenology records of 148 herbaceous species, which were observed for a single year by the PhenObs network in 15 botanical gardens. For each species, we characterised the spatial variability in six different phenological stages across gardens. We used boosted regression trees to link these variabilities in phenology to the variability in environmental parameters (temperature, latitude and local habitat conditions) as well as species traits (seed mass, vegetative height, specific leaf area and temporal niche) hypothesised to be related to phenology variability. We found that spatial variability in the phenology of herbaceous species was mainly driven by the variability in temperature but also photoperiod was an important driving factor for some phenological stages. In addition, we found that early-flowering and less competitive species characterised by small specific leaf area and vegetative height were more variable in their phenology. Our findings contribute to the field of phenology by showing that besides temperature, photoperiod and functional traits are important to be included when spatial variability of herbaceous species is investigated.


Asunto(s)
Fotoperiodo , Hojas de la Planta , Temperatura , Estaciones del Año , Hojas de la Planta/fisiología , Fenotipo , Plantas , Cambio Climático
3.
Ecol Evol ; 13(11): e10729, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38034336

RESUMEN

When habitat use by field-dwelling animals coincides in space and time with agricultural practices such as spring mowing of meadows, human-wildlife conflicts can have deadly consequences for wildlife. Roe deer (Capreolus capreolus L.) fawns are particularly vulnerable because they hide in meadows during the rearing phase. Thus, a better understanding of the habitat drivers of bed-site selection is critical to mitigating fawn mortality during mowing. Here, we tease apart the among-field (presumably driven by maternal behaviour) and within-field (driven by fawn behaviour) components of bed-site selection of roe deer during the spring mowing season. We collected over 600 fawn bed sites across an environmentally diverse study region. At the among-field scale, we implemented a used versus available design and employed a two-part statistical model (GAMLSS) to identify habitat characteristics that were linked to either fawn presence (vs. absence) or abundance on a given field. At the within-field scale, we compared habitat characteristics at fawn bed-sites with paired random sites using a conditional logistic regression model. At the among-field scale, fawns were more likely to be present, and were more abundant, in fields within more diverse, rural landscapes, with nearby woodland. Surprisingly, fawns were more often present in fields that were near roads and had lower vegetation productivity. At the within-field scale, however, fawns preferred bed-sites which were further from both roads and woodland, but that provided the best visual cover to minimise predation risk. Our findings revealed substantial and novel scale-dependent differences in the drivers of habitat selection of mothers and fawns, which, together, determine the precise locations of bed-sites between and within meadows. These results may aid wildlife managers in identifying areas where there is a high probability of encountering a roe deer fawn so as to initiate targeted searches prior to mowing and, ultimately, mitigate fawn mowing mortality.

4.
Microb Ecol ; 86(4): 3082-3096, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37875737

RESUMEN

Roe deer (Capreolus capreolus) are found in various habitats, from pure forest cultures to agricultural areas and mountains. In adapting to the geographically and seasonally differentiating food supply, they depend, above all, on an adapted microbiome. However, knowledge about the microbiome of wild ruminants still needs to be improved. There are only a few publications for individual species with a low number of samples. This study aims to identify a core microbiota for Bavarian roe deer and present nutrient and microbiota portraits of the individual habitat types. This study investigated the roe deer's rumen (reticulorumen) content from seven different characteristic Bavarian habitat types. The focus was on the composition of nutrients, fermentation products, and the rumen bacterial community. A total of 311 roe deer samples were analysed, with the most even possible distribution per habitat, season, age class, and gender. Significant differences in nutrient concentrations and microbial composition were identified for the factors habitat, season, and age class. The highest crude protein content (plant protein and microbial) in the rumen was determined in the purely agricultural habitat (AG), the highest value of non-fibre carbohydrates in the alpine mountain forest, and the highest fibre content (neutral detergent fibre, NDF) in the pine forest habitat. Maximum values for fibre content go up to 70% NDF. The proportion of metabolites (ammonia, lactate, total volatile fatty acids) was highest in the Agriculture-Beech-Forest habitat (ABF). Correlations can be identified between adaptations in the microbiota and specific nutrient concentrations, as well as in strong fluctuations in ingested forage. In addition, a core bacterial community comprising five genera could be identified across all habitats, up to 44% of total relative abundance. As with all wild ruminants, many microbial genera remain largely unclassified at various taxonomic levels. This study provides a more in-depth insight into the diversity and complexity of the roe deer rumen microbiota. It highlights the key microorganisms responsible for converting naturally available nutrients of different botanical origins.


Asunto(s)
Ciervos , Microbiota , Animales , Rumen/microbiología , Bosques , Bacterias , Nutrientes
5.
Front Microbiol ; 14: 1238744, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37849922

RESUMEN

As an inhabitant of the Alps, chamois are exposed to significant climatic changes throughout the year and are also strongly confronted with changing forage availability. Besides horizontal and vertical migratory movements as an adaptation, it undergoes physiological transformations and dynamic changes in the ruminal microbiota. The following study used 48 chamois of different ages and genders to investigate to which extent the ingested food plants, the resulting crude nutrients in the rumen (reticulorumen) contents, and the bacterial microbiota in the rumen and their fermentation products were influenced by the changes over the seasons. Very little is known about the microbiota of wild ruminants, and many bacterial taxa could only be determined to certain taxonomic levels in this study. However, adapted microbiota reflects the significant changes in the ingested forage and the resulting crude nutrients. For some taxa, our results indicated potential functional relationships. In addition, 15 genera were identified, representing almost 90% of the relative abundance, forming the central part of the microbial community throughout the year. The successful and flexible adaptation of chamois is reflected in the chamois rumen's nutrient and microbial profile. This is also the first study that analyzes the microbiota of the chamois using rumen samples and considers the microbiota in a seasonal comparison.

6.
J Funct Biomater ; 13(4)2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36412873

RESUMEN

This study evaluated the efficacy of experimental TEGDMA-functionalized dicalcium phosphate dihydrate (T-DCPD) filler-based resin-based composites (RBC) in preventing caries lesions around the restoration margins (secondary caries, SC). Standardized Class-II cavities were made in sound molars with the cervical margin in dentin. Cavities were filled with a commercial resin-modified glass-ionomer cement (RMGIC) or experimental RBCs containing a bisGMA-TEGDMA resin blend and one of the following inorganic fractions: 60 wt.% Ba glass (RBC-0); 40 wt.% Ba glass and 20 wt.% T-DCPD (RBC-20); or 20 wt.% Ba glass and 40 wt.% T-DCPD (RBC-40). An open-system bioreactor produced Streptococcus mutans biofilm-driven SC. Specimens were scanned using micro-CT to evaluate demineralization depths. Scanning electron microscopy and energy-dispersive X-ray spectroscopy characterized the specimen surfaces, and antimicrobial activity, buffering effect, and ion uptake by the biofilms were also evaluated. ANOVA and Tukey's tests were applied at p < 0.05. RBC-0 and RBC-20 showed SC development in dentin, while RBC-40 and RMGIC significantly reduced the lesion depth at the restoration margin (p < 0.0001). Initial enamel demineralization could be observed only around the RBC-0 and RBC-20 restorations. Direct antibiofilm activity can explain SC reduction by RMGIC, whereas a buffering effect on the acidogenicity of biofilm can explain the behavior of RBC-40. Experimental RBC with CaP-releasing functionalized T-DCPD filler could prevent SC with the same efficacy as F-releasing materials.

7.
New Phytol ; 235(6): 2199-2210, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35762815

RESUMEN

Phenology has emerged as key indicator of the biological impacts of climate change, yet the role of functional traits constraining variation in herbaceous species' phenology has received little attention. Botanical gardens are ideal places in which to investigate large numbers of species growing under common climate conditions. We ask whether interspecific variation in plant phenology is influenced by differences in functional traits. We recorded onset, end, duration and intensity of initial growth, leafing out, leaf senescence, flowering and fruiting for 212 species across five botanical gardens in Germany. We measured functional traits, including plant height, absolute and specific leaf area, leaf dry matter content, leaf carbon and nitrogen content and seed mass and accounted for species' relatedness. Closely related species showed greater similarities in timing of phenological events than expected by chance, but species' traits had a high degree of explanatory power, pointing to paramount importance of species' life-history strategies. Taller plants showed later timing of initial growth, and flowered, fruited and underwent leaf senescence later. Large-leaved species had shorter flowering and fruiting durations. Taller, large-leaved species differ in their phenology and are more competitive than smaller, small-leaved species. We assume climate warming will change plant communities' competitive hierarchies with consequences for biodiversity.


Asunto(s)
Cambio Climático , Reproducción , Biodiversidad , Flores , Plantas , Estaciones del Año
8.
Dent Mater ; 38(8): 1376-1384, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35773036

RESUMEN

OBJECTIVES: When consumed in excess, acidic foods and beverages can cause dental erosions leading to irreversible loss of tooth substance. In many cases, prosthetic rehabilitation of the damaged teeth is mandatory. The aim of this in vitro study was to investigate, for the first time on this scale, the resistance of various commonly used self-adhesive resin luting cements (Bifix SE, VOCO; G-Cem LinkAce, GC; RelyX Unicem, 3 M Oral Care; SpeedCEM Plus, Ivoclar ) against acidic media, and to find out whether they can withstand long-term exposure. These results were compared with an adhesive resin luting cement (Panavia V5, Kuraray) that functioned as reference gold standard. Furthermore we applied area roughness parameters for surface texture analysis in the present investigation, to highlight their advantages for investigations on the surface quality of resin luting cements. METHODS: Six specimens with identical diameter (10 mm) and thickness (3 mm) were prepared from each self-adhesive and adhesive resin luting cement and forwarded to an incubation in various acidic media for a period of 232 h. Conductivity and pH-values of each acidic medium was analyzed for each material group prior (t 0) and after exposure (t 1). The specimens were examined for Vickers microhardness and surface quality. For the evaluation of surface roughness, the parameters Sa, Sdr, Spc Spk, Sk, and Svk were investigated by using different filtered surfaces (S-L; S-F) according to ISO 25 178. Statistical analysis was conducted at a significance level of α = 0.050. RESULTS: For the evaluation of the acid resistance of self-adhesive resin luting cements investigations on conductivity and pH-value assessment of storage solution appear unsuitable, while the assessment of microhardness and surface analysis revealed valid data. It could be shown that changes in surface texture of the resin luting cements can be determinend in qualitative and quantitative manner. While the microhardness and surface quality of some resin luting cements hardly changed, others showed significantly reduced values in microhardness and changes in their surface quality (p < 0.001). SIGNIFICANCE: The data of the current study emphasize the relevance of interactions between resin luting cements and acids and suggest further laboratory and clinical studies to elucidate its impact on the clinical performance of the materials investigated.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Resina , Cementos Dentales , Ensayo de Materiales
9.
Eur Heart J Cardiovasc Imaging ; 23(2): 246-254, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-33615333

RESUMEN

AIMS: Left heart diseases (LHDs) are the main driving forces for the development of functional tricuspid regurgitation (TR). Therefore, in most cases, the true prognostic value of TR remains concealed by concomitant LHD. This study aimed to analyse right heart remodelling in patients with TR without other valve disease and with normal systolic left ventricular function (sysLVF), and to stratify its prognostic value in the presence (dPH, maximal TR velocity signal (TRVmax) ≥ 3.5 m/s in echocardiography) or absence (nsPH, TRVmax < 3.5m/s) of concomitant pulmonary hypertension (PH). METHODS AND RESULTS: We performed an observational analysis of all patients diagnosed with TR in the absence of other valve disease and reduced sysLVF at our institution between 1 January 2003 and 31 December 2013. Five-year mortality was chosen as endpoint. The final cohort entailed 29 979 consecutive patients (median age 60 years, interquartile range 46-70), 49.9% were male, mean follow-up was 95±49 months. Severe TR was present in 790 patients (2.6%). In dPH and in nsPH, severe TR was associated with an excess 5-year mortality that was even more pronounced in the dPH group (58.2% vs. 43.6%, P = 0.001). In nsPH, right ventricular dysfunction predicted mortality. In dPH, mortality was independent of presence or absence of right heart dilatation or dysfunction. CONCLUSION: Severe TR without concomitant left heart valve disease or LV systolic dysfunction was a rare disease in this large-scale all-comer population and is associated with an unfavourable prognosis. The differentiation of patients with nsPH and dPH is essential as they present with different patterns of right heart remodelling and with different long-time outcomes.


Asunto(s)
Hipertensión Pulmonar , Insuficiencia de la Válvula Tricúspide , Disfunción Ventricular Derecha , Ecocardiografía/métodos , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Insuficiencia de la Válvula Tricúspide/complicaciones , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen
10.
J Clin Med ; 10(11)2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34073744

RESUMEN

BACKGROUND: Presence of severe tricuspid regurgitation (TR) has a significant impact on assessment of right ventricular function (RVF) in transthoracic echocardiography (TTE). High trans-valvular pendulous volume leads to backward-unloading of the right ventricle. Consequently, established cut-offs for normal systolic performance may overestimate true systolic RVF. METHODS: A retrospective analysis was performed entailing all patients who underwent TTE at our institution between 1 January 2013 and 31 December 2016. Only patients with normal left ventricular systolic function and with no other valvular lesion were included. All recorded loops were re-read by one experienced examiner. Patients without severe TR (defined as vena contracta width ≥7 mm) were excluded. All-cause 2-year mortality was chosen as the end-point. The prognostic value of several RVF parameters was tested. RESULTS: The final cohort consisted of 220 patients, 88/220 (40%) were male. Median age was 69 years (IQR 52-79), all-cause two-year mortality was 29%, median TAPSE was 19 mm (15-22) and median FAC was 42% (30-52). In multivariate analysis, TAPSE with the cutoff 17 mm and FAC with the cutoff 35% revealed non-significant hazard ratios (HR) of 0.75 (95%CI 0.396-1.421, p = 0.38) and 0.845 (95%CI 0.383-1.867, p = 0.68), respectively. TAPSE with the cutoff 19 mm and visual eyeballing significantly predicted survival with HRs of 0.512 (95%CI 0.296-0.886, p = 0.017) and 1.631 (95%CI 1.101-2.416, p = 0.015), respectively. CONCLUSIONS: This large-scale all-comer study confirms that RVF is one of the main drivers of mortality in patients with severe isolated TR. However, the current cut-offs for established echocardiographic parameters did not predict survival. Further studies should investigate the prognostic value of higher thresholds for RVF parameters in these patients.

11.
Int J Cardiovasc Imaging ; 37(2): 577-586, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33029699

RESUMEN

Left ventricular ejection fraction (LVEF) is the most important parameter in the assessment of cardiac function. A machine-learning algorithm was trained to guide ultrasound-novices to acquire diagnostic echocardiography images. The artificial intelligence (AI) algorithm then estimates LVEF from the captured apical-4-chamber (AP4), apical-2-chamber (AP2), and parasternal-long-axis (PLAX) loops. We sought to test this algorithm by having first-year medical students without previous ultrasound knowledge scan real patients. Nineteen echo-naïve first-year medical students were trained in the basics of echocardiography by a 2.5 h online video tutorial. Each student then scanned three patients with the help of the AI. Image quality was graded according to the American College of Emergency Physicians scale. If rated as diagnostic quality, the AI calculated LVEF from the acquired loops (monoplane and also a "best-LVEF" considering all views acquired in the particular patient). These LVEF calculations were compared to images of the same patients captured and read by three experts (ground-truth LVEF [GT-EF]). The novices acquired diagnostic-quality images in 33/57 (58%), 49/57 (86%), and 39/57 (68%) patients in the PLAX, AP4, and AP2, respectively. At least one of the three views was obtained in 91% of the attempts. We found an excellent agreement between the machine's LVEF calculations from images acquired by the novices with the GT-EF (bias of 3.5% ± 5.6 and r = 0.92, p < 0.001 in the "best-LVEF" algorithm). This pilot study shows first evidence that a machine-learning algorithm can guide ultrasound-novices to acquire diagnostic echo loops and provide an automated LVEF calculation that is in agreement with a human expert.


Asunto(s)
Competencia Clínica , Ecocardiografía , Cardiopatías/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador , Aprendizaje Automático , Volumen Sistólico , Estudiantes de Medicina , Función Ventricular Izquierda , Adulto , Anciano , Femenino , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados
12.
Pharmaceutics ; 12(12)2020 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-33302527

RESUMEN

In this study, we integrated different calcium sources into sol-gel hybrid glass scaffolds with the aim of producing implants with long-lasting calcium release while maintaining mechanical strength of the implant. Calcium(II)-release was used to introduce bioactivity to the material and eventually support implant integration into a bone tissue defect. Tetraethyl orthosilicate (TEOS) derived silica sols were cross-linked with an ethoxysilylated 4-armed macromer, pentaerythritol ethoxylate and processed into macroporous scaffolds with defined pore structure by indirect rapid prototyping. Triethyl phosphate (TEP) was shown to function as silica sol solvent. In a first approach, we investigated the integration of 1 to 10% CaCl2 in order to test the hypothesis that small CaCl2 amounts can be physically entrapped and slowly released from hybrid glass scaffolds. With 5 and 10% CaCl2 we observed an extensive burst release, whereas slightly improved release profiles were found for lower Calcium(II) contents. In contrast, introduction of melt-derived bioactive 45S5 glass microparticles (BG-MP) into the hybrid glass scaffolds as another Calcium(II) source led to an approximately linear release of Calcium(II) in Tris(hydroxymethyl)aminomethane (TRIS) buffer over 12 weeks. pH increase caused by BG-MP could be controlled by their amount integrated into the scaffolds. Compression strength remained unchanged compared to scaffolds without BG-MP. In cell culture medium as well as in simulated body fluid, we observed a rapid formation of a carbonated hydroxyapatite layer on BG-MP containing scaffolds. However, this mineral layer consumed the released Calcium(II) ions and prevented an additional increase in Calcium(II) concentration in the cell culture medium. Cell culture studies on the different scaffolds with osteoblast-like SaOS-2 cells as well as bone marrow derived mesenchymal stem cells (hMSC) did not show any advantages concerning osteogenic differentiation due to the integration of BG-MP into the scaffolds. Nonetheless, via the formation of a hydroxyapatite layer and the ability to control the pH increase, we speculate that implant integration in vivo and bone regeneration may benefit from this concept.

13.
Swiss Dent J ; 130(12): 1005-1010, 2020 Dec 07.
Artículo en Alemán | MEDLINE | ID: mdl-33267573

RESUMEN

OBJECTIVES: An abnormal development of teeth can result in malformed teeth. Indirect resin composites that can be fabricated with the computer-aided design/computer-aided manufacturing (CAD/ CAM) technique are available for the fabrication of permanent restorations. This case report presents the esthetical and functional rehabilitation of a 10-year-old female patient with oligodontia and conical canines. MATERIAL AND METHODS: Crowns fabricated from indirect resin composites were milled and polished to restore the conical canines 23, 33, and 43 (FDI). In addition, direct resin composite fillings were applied to teeth 53, 52, and 11, and a resin-bonded fixed dental prosthesis with single-retainer design fabricated from zirconia ceramic that was partially veneered with silica-based ceramic was inserted to replace tooth 22. RESULTS: The young patient and her parents were very satisfied with the functional and esthetical results of the resin composite crowns after insertion. Oral hygiene measures were demonstrated, and could be easily realized by the girl. Since only a few clinical studies are available, the clinical longevity of permanent restorations fabricated from indirect resin composite has not yet been proven. In this case report, indirect resin composites were used to achieve esthetically and functionally pleasing results treating conical teeth.


Asunto(s)
Resinas Compuestas , Diseño de Prótesis Dental , Cerámica , Niño , Diseño Asistido por Computadora , Coronas , Femenino , Humanos
14.
Sci Rep ; 10(1): 18041, 2020 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-33093500

RESUMEN

Classically, neurexins are thought to mediate synaptic connections through trans interactions with a number of different postsynaptic partners. Neurexins are cleaved by metalloproteases in an activity-dependent manner, releasing the soluble extracellular domain. Here, we report that in both immature (before synaptogenesis) and mature (after synaptogenesis) hippocampal neurons, the soluble neurexin-1ß ectodomain triggers acute Ca2+-influx at the dendritic/postsynaptic side. In both cases, neuroligin-1 expression was required. In immature neurons, calcium influx required N-type calcium channels and stimulated dendritic outgrowth and neuronal survival. In mature glutamatergic neurons the neurexin-1ß ectodomain stimulated calcium influx through NMDA-receptors, which increased presynaptic release probability. In contrast, prolonged exposure to the ectodomain led to inhibition of synaptic transmission. This secondary inhibition was activity- and neuroligin-1 dependent and caused by a reduction in the readily-releasable pool of vesicles. A synthetic peptide modeled after the neurexin-1ß:neuroligin-1 interaction site reproduced the cellular effects of the neurexin-1ß ectodomain. Collectively, our findings demonstrate that the soluble neurexin ectodomain stimulates growth of neurons and exerts acute and chronic effects on trans-synaptic signaling involved in setting synaptic strength.


Asunto(s)
Proteínas de Unión al Calcio/farmacología , Calcio/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/fisiología , Moléculas de Adhesión de Célula Nerviosa/farmacología , Transmisión Sináptica/efectos de los fármacos , Animales , Proteínas de Unión al Calcio/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Células Cultivadas , Hipocampo/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Neuronas/metabolismo , Ratas Wistar , Receptores de N-Metil-D-Aspartato/metabolismo , Solubilidad , Estimulación Química
15.
Drugs R D ; 20(2): 115-124, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32335854

RESUMEN

BACKGROUND AND OBJECTIVE: Beyond its application for diagnostics in patients, esophagogastroduodenoscopy (EGD) is used to assess gastrointestinal drug effects in clinical trials, where the interpretation of any pathological findings depends on the respective background variability. The objective of this analysis was to characterize the occurrence of pathological findings in the upper gastrointestinal tract in symptom-free healthy individuals. METHODS: A baseline EGD was performed in clinically healthy individuals in three clinical trials aimed to assess gastrointestinal tolerability of drugs. Pathological findings were described by type (redness, erosion, ulcer or other), number, size and location, and by clinical relevance as assessed by the endoscopist. Characteristics of volunteers were tested as potential covariates. RESULTS: A total of 294 EGDs were assessed. Characteristics of individuals were as follows: 257 (87.4%) males, age (mean ± SD) 32.0 ± 8.1 years, body weight 76.0 ± 10.6 kg, body mass index (BMI) 24.0 ± 2.5 kg/m2, 200 consumed alcohol, 250 (of 290 where this information was available) consumed caffeine and 39 (of 152) were smokers, 30 (of 151) tested positive for H. pylori. Any pathological finding was present in 79.6%. Clinically relevant findings occurred in 44.2%, mainly erosions (39.1%). Nine stomach ulcers were observed. Only age and BMI had a statistically significant relationship to overall pathological findings [age 3.4 years higher (p = 0.027), and BMI 1.6 kg/m2 higher (p < 0.001); for clinically relevant vs no findings]. CONCLUSION: Upper gastrointestinal tract mucosal lesions, including those assessed as clinically relevant, are frequent in clinically healthy individuals, impeding the assessment of causality for both disease and drug effects on gastrointestinal health.


Asunto(s)
Endoscopía del Sistema Digestivo , Tracto Gastrointestinal Superior/patología , Adulto , Endoscopía del Sistema Digestivo/instrumentación , Femenino , Voluntarios Sanos , Humanos , Masculino
16.
Dent Mater ; 36(5): 603-616, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32238271

RESUMEN

OBJECTIVES: Modern dentistry is increasingly focusing on digital procedures, including CAD/CAM technologies. New materials have to resist in a demanding environment that includes secondary caries occurrence. The current study hypothesized that the microbiological behavior of different RBCs for CAD/CAM applications is better than that of their counterparts for direct restorations due to differences in the surface characteristics. METHODS: Both direct and CAD/CAM RBCs were tested. Specimens were obtained from each group, polished, cleaned, stored in artificial saliva (1w), then sterilized under UV (24h). Specimens' surface was assessed using profilometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction; resin/filler content was assessed using thermogravimetry. After pre-incubation with sterile human saliva (24h), the microbiological behavior of the materials was assessed using four models: Streptococcus mutans adherence (2h), S. mutans biofilm formation in an orbital shaking bioreactor (24h), S. mutans biofilm formation in a continuous-flow bioreactor simulating shear forces (24h), and mixed-plaque formation in the bioreactor (24h). The viable biomass adhering to the specimens' surfaces was measured using a tetrazolium dye-based test. Statistical analysis included verification of normality of distribution and homoscedasticity, then Oneway ANOVA and Tukey's test (α=5%). RESULTS: When using the bioreactor setup, CAD/CAM RBCs generally yielded lower S. mutans and mixed-plaque biofilm formation compared to direct RBCs. This difference was not evidenced in the first two microbiological models. Differences in manufacturing and curing processes rather than in materials' surface roughness and composition could explain these results. SIGNIFICANCE: CAD/CAM RBCs are promising materials from a microbiological point of view, featuring reduced biofilm formation on their surfaces when shear conditions similar to in vivo ones are present.


Asunto(s)
Resinas Compuestas , Materiales Dentales , Biopelículas , Diseño Asistido por Computadora , Humanos , Ensayo de Materiales , Propiedades de Superficie
17.
Materials (Basel) ; 13(5)2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32120932

RESUMEN

This paper reports a numerical approach for modelling the thermal behavior and heat accumulation/liberation of sustainable cementitious composites made with Recycled Brick Aggregates (RBAs) employed as carriers for Phase-Change Materials (PCMs). In the framework of the further development of the fixed grid modelling method, classically employed for solving the well-known Stefan problem, an enthalpy-based approach and an apparent calorific capacity method have been proposed and validated. More specifically, the results of an experimental program, following an advanced incorporation and immobilization technique, developed at the Institut für Werkstoffe im Bauwesen for investigating the thermal responses of various combinations of PCM-RBAs, have been considered as the benchmark to calibrate/validate the numerical results. Promising numerical results have been obtained, and temperature simulations showed good agreement with the experimental data of the analyzed mixtures.

18.
Clin Oral Investig ; 24(9): 3009-3016, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31807923

RESUMEN

OBJECTIVES: The aim of this study was to analyse the impact of different clinical conditioning approaches and an ammonium polyfluoride- and trimethoxysilylpropyl methacrylate-based experimental primer for intraoral luting of buccal tubes on silica-based ceramic surfaces. MATERIALS AND METHODS: A total of 60 leucite-reinforced glass ceramic molar crowns were conditioned using different methods (n = 10): I-roughening, hydrofluoric acid, silane; II-roughening, silane; III-roughening, experimental coupling agent; IV-experimental coupling agent; V-roughening; VI-no treatment. A buccal tube was adhesively luted to the ceramic surface. Subsequently, water storage, thermocycling and chewing simulation were carried out. The shear bond strength (SBS) was determined, and changes in the surface were assessed. RESULTS: All tubes of the control group (group VI) debonded after incubation. The conditioning methods using coupling agents revealed mean values for SBS of 61.56 MPa (group I), 45.53 MPa (group III), 41.65 MPa (group II), and 23.14 MPa (group IV). In groups I-III, both composite residues and cracks/tear-outs were detected. CONCLUSIONS: The conditioning of silicate ceramic surfaces with a suitable coupling agent system appears to allow sufficient adhesive luting of buccal tubes. The intraoral luting of fixed appliance elements on silicate ceramic surfaces using an ammonium polyfluoride- and trimethoxysilylpropyl methacrylate-based ceramic primer can withstand orthodontic forces. CLINICAL RELEVANCE: Ammonium polyfluoride- and trimethoxysilylpropyl methacrylate-based ceramic primers revealed promising results for the intraoral adhesive luting of orthodontic devices to silica-based ceramic crowns.


Asunto(s)
Coronas , Recubrimiento Dental Adhesivo , Cementos Dentales , Dióxido de Silicio , Cerámica , Grabado Dental , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Silanos , Propiedades de Superficie
19.
PLoS One ; 14(4): e0214993, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30978218

RESUMEN

Effective preventive strategies are available to control Echinococcus multilocularis in foxes in order to reduce the human infection risk. Reduction of E. multilocularis prevalence in foxes was achieved in various studies by distributing praziquantel-containing bait by hand or by aircraft in either rural or settlement areas. Here, an integrated approach is described from southern Germany (district of Starnberg). Baseline data were obtained in winter 2002/03, when the prevalence rate in the project area was 51%. Between December 2005 and December 2011, air distribution of bait in agricultural and recreational areas was combined with distribution by hand in towns and villages, in order to cover the entire fox population, with a bait density of 50 pieces / km2 (baiting area: 213 km2). In addition, a control area without anthelmintic treatment was selected. Prevalence was reduced in the baiting area to 1% by March 2007. Subsequently, from 2007 to the end of 2011, prevalence rates remained at a low level with 2.4% (2007), 2.4% (2008), 2.6% (2009), 1.2% (2010) and 0.0% (2011). In the un-baited control area the prevalence rates remained high, ranging from 19.6% to 35.1% with an average of 27.3%. During the 6 years of anthelmintic treatment, differences between baiting and control areas were highly significant (P<0.001). In the suburban and urban parts of the study area prevalence could be reduced to less than 1%, i.e. to a level below the limit of detection, which was maintained even after the measures had been discontinued. The applicability and effectiveness of anthelmintic baiting was therefore confirmed even for a heavily settled and fragmented landscape, which posed challenges for practical application of the control measures. The cost of the project ranged between € 1.70 and € 2.00 per inhabitant of the baiting area per year.


Asunto(s)
Antihelmínticos/farmacología , Equinococosis , Echinococcus multilocularis , Zorros/parasitología , Praziquantel/farmacología , Estaciones del Año , Animales , Equinococosis/epidemiología , Equinococosis/prevención & control , Equinococosis/veterinaria , Alemania/epidemiología , Humanos , Prevalencia
20.
Neuroscience ; 401: 106-116, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30668973

RESUMEN

The striatum of the basal ganglia is pivotal for voluntary movements and is implicated in debilitating movement disorders such as Parkinsonism and dystonia. Striatum projects to downstream nuclei through direct (dSPN) and indirect (iSPN) pathway projection neurons thought to exert opposite effects on movement. In rodent models of striatal function, unilateral dopamine deprivation induces ipsiversive rotational behavior. The dSPNs of the dorsal striatum are believed to engage distinct motor programs but underlying mechanisms remain unclear. Here, we show by employing chemogenetics [Designer Receptors Exclusively Activated by Designer Drugs (DREADDs)] that unilateral inhibition of dorsomedial dSPNs is sufficient to selectively impair contraversive movement and elicit ipsiversive rotational behavior in mice. Adeno-associated virus (AAV) encoding Cre-dependent Gi-coupled DREADD was injected unilaterally into the dorsomedial striatum of Drd1-Cre mice, resulting in expression of the modified human M4 muscarinic receptor (hM4Di) in ∼20% of dorsostriatal dSPNs. Upon hM4Di activation, a striking positive linear correlation was found between turn ratio and viral expression, which corroborates a relationship between unilateral inhibition of dorsomedial dSPNs and rotational behavior. Bursts of ipsiversive rotations were interspersed with normal ambulation. However, partial unilateral inhibition of ∼20% of dorsostriatal dSPNs did not affect horizontal and vertical locomotion or forelimb use preference. Overall, our results substantiate a unique role of dSPNs in promoting response bias in rotational behavior and show this to be a highly sensitive measure of dSPN performance.


Asunto(s)
Drogas de Diseño/farmacología , Neostriado/fisiología , Vías Nerviosas/fisiología , Neuronas/fisiología , Animales , Ganglios Basales/metabolismo , Conducta Animal , Cuerpo Estriado/citología , Cuerpo Estriado/metabolismo , Humanos , Ratones , Ratones Noqueados , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Neostriado/citología , Neostriado/efectos de los fármacos , Vías Nerviosas/efectos de los fármacos , Neuritas/metabolismo , Neuronas/citología , Neuronas/efectos de los fármacos , Trastornos Parkinsonianos/metabolismo , Receptor Muscarínico M4/metabolismo , Receptores de Dopamina D1/metabolismo , Rotación
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