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1.
Lancet Neurol ; 20(3): 235-246, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33609480

RESUMEN

Sporadic Creutzfeldt-Jakob disease is a fatal neurodegenerative disease caused by misfolded prion proteins (PrPSc). Effective therapeutics are currently not available and accurate diagnosis can be challenging. Clinical diagnostic criteria use a combination of characteristic neuropsychiatric symptoms, CSF proteins 14-3-3, MRI, and EEG. Supportive biomarkers, such as high CSF total tau, could aid the diagnostic process. However, discordant studies have led to controversies about the clinical value of some established surrogate biomarkers. Development and clinical application of disease-specific protein aggregation and amplification assays, such as real-time quaking induced conversion (RT-QuIC), have constituted major breakthroughs for the confident pre-mortem diagnosis of sporadic Creutzfeldt-Jakob disease. Updated criteria for the diagnosis of sporadic Creutzfeldt-Jakob disease, including application of RT-QuIC, should improve early clinical confirmation, surveillance, assessment of PrPSc seeding activity in different tissues, and trial monitoring. Moreover, emerging blood-based, prognostic, and potentially pre-symptomatic biomarker candidates are under investigation.

2.
Oral Health Prev Dent ; 18(1): 991-998, 2020 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-33215490

RESUMEN

PURPOSE: This study aimed to explore self-reported oral hygiene practices (OHPs) among Hungarian adult e-cigarette-only (former smokers who switched completely to e-cigarette use or vaping) and dual users (smokers who use e-cigarettes and combustible tobacco cigarettes concomitantly). MATERIALS AND METHODS: A cross-sectional, web-based survey of 930 adult Hungarian e-cigarette users was conducted in 2015. Participants reported 10 OHPs, which were included in analyses as separate binary variables and as a composite variable of the 10 OHP items (inadequate/adequate). Chi-square test was used to explore whether separate OHPs differ by vaping status, and to examine the relationship between inadequate OHPs and past combustible or e-cigarette use characteristics. Associations between separate OHPs and vaping status, and between inadequate OHPs and vaping status were tested by multiple logistic regression analyses. RESULTS: More dual users reported toothbrushing twice a day or more than e-cigarette-only users (73.6% vs 65.3%, respectively, p = 0.041) and using sugar-free chewing gum (57.7% vs 45.8%, respectively, p = 0.006) while adequacy of other OHPs did not differ statistically significantly by vaping status. Inadequate OHPs were more typical in the sample (63.7%) than adequate OHPs, however, inadequate OHPs did not differ statistically significantly among dual users and e-cigarette-only users (62.0% vs 64.0%, respectively, OR = 1.20, p = 0.400), controlling for age, gender, education, past combustible and current e-cigarette use characteristics. CONCLUSION: In this study, both e-cigarette-only and dual users demonstrated similarly high prevalence of inadequate OHPs. Therefore dentists should educate them about effective OHPs and the role of tobacco and e-cigarette use in the development of oral diseases.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Adulto , Estudios Transversales , Humanos , Hungría/epidemiología , Higiene Bucal
3.
BMC Oral Health ; 20(1): 287, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33076894

RESUMEN

BACKGROUND: The spread of digital technology in dentistry poses new challenges and sets new goals for dentists. The aim of the present in vivo study was to determine the learning curve of intraoral scanning described by (1) scanning time and (2) image number (count of images created by intraoral scanner during the scanning process). METHODS: Ten dental students of Semmelweis University took part in the study. Dental students took digital study impressions using a 3Shape Trios 3® (3Shape, Copenhagen, Denmark) intraoral scanning device. Each student took 10 digital impressions on volunteers. Volunteer inclusion criteria included full dentition (except for missing third molars) and no prosthetic/restorative treatment. Digital impression taking was preceded by tuition consisting of both theoretical education and practical training. Digital impressions were taken of the upper and lower arches, and the bite was recorded according to the manufacturer's instructions. Total scanning times and image numbers were recorded. RESULTS: The difference in scanning time between the first and the tenth digital impressions was significant (p = 0.007). The average scanning time for the first impressions was 23 min 9 s; for the tenth impressions, it was 15 min 28 s. The difference between the scanning times of the first and the tenth procedures was 7 min 41 s. The average image count for the first impressions was 1964.5; for the tenth impressions, it was 1468.6. The image count difference between the first and the tenth procedures was 495.9. The image count versus sequential number of measurement curve shows an initial decreasing tendency followed by a trough around the sixth measurement and a final increasing phase. CONCLUSION: Our results indicate an association between the sequential number of measurements and the outcome variables. The drop in scanning time is probably explained by a practice effect of repeated use, i.e. the students learned to move the scanning tip faster. The image count first showed a decreasing tendency, and after the sixth measurement, it increased; there was no consistent decline in mean scan count. Shorter scanning times are associated with poorer coverage quality, with the operator needing to make corrections by adding extra images; this manifests as the time function of image counts taking an increase after the sixth measurement.

5.
J Craniofac Surg ; 2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-33055558

RESUMEN

The purpose of this study is to evaluate national differences in inpatient outcomes and predictors of treatment type for endoscopic versus open surgery for craniosynostosis, with particular consideration of racial, socioeconomic, and geographic factors. The 2016 Kids' Inpatient Database was queried to identify patients aged 3 years or younger who underwent craniectomy for craniosynostosis. Multivariable regression modeled treatment type based on patient-level (gender, race, income, comorbidities, payer) and facility-level (bed size, region, teaching status) variables, and was used to assess outcomes. The weighted sample included 474 patients, of whom 81.9% (N = 388) of patients underwent open repair and 18.1% (N = 86) underwent endoscopic repair. A total of 81.1% of patients were under 1 year of age and 12.0% were syndromic. Patients were more likely to be treated open if they were older (odds ratio [OR] 3.07, P = 0.005) or syndromic (OR 8.56, P = 0.029). Patients who underwent open repair were more likely to receive transfusions (OR 2.86, P = 0.021), and have longer lengths of stay (OR 1.02, P < 0.001) and more costly hospitalizations (OR 5228.78, P = 0.018). Complications did not significantly vary between procedure type. The authors conclude that United States national data confirm benefits of endoscopic surgery, including a lower risk of transfusion, shorter hospital stay, and lower hospital costs, without a significant change in the rate of inpatient complications. Racial, socioeconomic, and geographic factors were not significantly associated with treatment type or perioperative surgical outcomes. Future studies are needed to further investigate the influence of such variables on access to craniofacial care.

6.
J Craniofac Surg ; 2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-33055559

RESUMEN

Cranioplasty lies at the intersection of neurosurgery and plastic surgery, though little is known about the impact of plastic surgery involvement. The authors hypothesized that adult cranioplasty patients at higher volume plastic surgery facilities would have improved inpatient outcomes. Adult cranioplasty encounters were extracted from the National Inpatient Sample from 2012 to 2014 based on International Classification of Diseases, Ninth Revision (ICD-9) codes. Regression models included the following variables: age, gender, race/ethnicity, Elixhauser Comorbidity Index, payer, hospital size, region, and urban/teaching status. Outcomes included odds of receiving a flap, perioperative patient safety indicators, and mortality. The weighted sample included 49,305 encounters with diagnoses of neoplasm (31.2%), trauma (56.4%), infection (5.2%), a combination of these diagnoses (3.9%), or other diagnoses (3.2%). There were 1375 inpatient mortalities, of which 10 (0.7%) underwent a flap procedure. On multivariable regression, higher volume plastic surgery facilities and all diagnoses except uncertain neoplasm were associated with an increased likelihood of a flap procedure during the admission for cranioplasty, using benign neoplasm as a reference (P < 0.001). Plastic surgery facility volume was not significantly associated with likelihood of a patient safety indicator event. The highest volume plastic surgery quartile was associated with lower likelihood of inpatient mortality (P = 0.008). These findings support plastic surgery involvement in adult cranioplasty and suggest that these patients are best served at high volume plastic surgery facilities.

7.
Int J Mol Sci ; 21(17)2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32878083

RESUMEN

Alzheimer's type dementia (AD) exhibits clinical heterogeneity, as well as differences in disease progression, as a subset of patients with a clinical diagnosis of AD progresses more rapidly (rpAD) than the typical AD of slow progression (spAD). Previous findings indicate that low cerebrospinal fluid (CSF) content of cell-free mitochondrial DNA (cf-mtDNA) precedes clinical signs of AD. We have now investigated the relationship between cf-mtDNA and other biomarkers of AD to determine whether a particular biomarker profile underlies the different rates of AD progression. We measured the content of cf-mtDNA, beta-amyloid peptide 1-42 (Aß), total tau protein (t-tau) and phosphorylated tau (p-tau) in the CSF from a cohort of 95 subjects consisting of 49 controls with a neurologic disorder without dementia, 30 patients with a clinical diagnosis of spAD and 16 patients with rpAD. We found that 37% of controls met at least one AD biomarker criteria, while 53% and 44% of subjects with spAD and rpAD, respectively, did not fulfill the two core AD biomarker criteria: high t-tau and low Aß in CSF. In the whole cohort, patients with spAD, but not with rpAD, showed a statistically significant 44% decrease of cf-mtDNA in CSF compared to control. When the cohort included only subjects selected by Aß and t-tau biomarker criteria, the spAD group showed a larger decrease of cf-mtDNA (69%), whereas in the rpAD group cf-mtDNA levels remained unaltered. In the whole cohort, the CSF levels of cf-mtDNA correlated positively with Aß and negatively with p-tau. Moreover, the ratio between cf-mtDNA and p-tau increased the sensitivity and specificity of spAD diagnosis up to 93% and 94%, respectively, in the biomarker-selected cohort. These results show that the content of cf-mtDNA in CSF correlates with the earliest pathological markers of the disease, Aß and p-tau, but not with the marker of neuronal damage t-tau. Moreover, these findings confirm that low CSF content of cf-mtDNA is a biomarker for the early detection of AD and support the hypothesis that low cf-mtDNA, together with low Aß and high p-tau, constitute a distinctive CSF biomarker profile that differentiates spAD from other neurological disorders.

8.
Clin Oral Investig ; 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32964309

RESUMEN

OBJECTIVES: (i) To develop, validate, and apply in practice a new risk assessment tool for erosive tooth wear (ETW) including a risk factors questionnaire and a saliva secretion evaluation, which combined with a clinical index, can be part of an ETW composite scoring system; (ii) to assess ETW lesions and current and past erosive challenges in younger age groups. METHODS: The Tooth Surface Loss/Erosion Working Group of the European Association of Dental Public Health consisted of an international panel of experts designed the survey component of the new tool (Erosive Wear Assessment of Risk-EWAR) and confirmed its construct and content validity. After receiving ethical approvals and informed consents, the EWAR tool (questionnaire + saliva secretion evaluation) was applied in a multicenter cross-sectional study with 207 participants aged 15-21 years old from four countries (Finland, Greece, Romania, the USA). BEWE score was used for the clinical assessment of ETW. RESULTS: A total of 58.5% of participants had ETW. 10.9% and 20.3% of participants had low secretion of stimulated (< 1 ml/min) and unstimulated saliva (< 0.25 ml/min), respectively. The following factors were bivariately significantly associated with ETW: energy drink consumption, low secretion of stimulated saliva, juices consumption, erosive drink consumption for quenching thirst between meals, erosive drink kept in the mouth, feeling pain/icing after consuming something acidic or cold, and co-existence of other type of tooth wear. In regression analysis, only energy drink consumption (OR = 3.5, 95% CI: 1.39, 8.9), low secretion of stimulated saliva (OR = 36.3, 95% CI: 4.71, 78.94), and feeling pain/icing (OR = 8.8, 95% CI: 1.92, 40.04) remained significant. CONCLUSIONS: The examiners of the study reported that the EWAR tool appeared to be an affordable and easy-to-use instrument. Some challenges occurred during the saliva collection process. Inferential analysis revealed that the risk factors/indicators of low stimulated salivary flow, energy drink consumption, and pain/icing with ETW were considered the most important in ETW occurrence. CLINICAL RELEVANCE: EWAR tool combined with the BEWE clinical index can be used for ETW risk assessment for epidemiological studies and chairside use.

9.
PLoS Med ; 17(8): e1003289, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32817639

RESUMEN

BACKGROUND: The ε4 allele of apolipoprotein E (APOE) gene and increasing age are two of the most important known risk factors for developing Alzheimer disease (AD). The diagnosis of AD based on clinical symptoms alone is known to have poor specificity; recently developed diagnostic criteria based on biomarkers that reflect underlying AD neuropathology allow better assessment of the strength of the associations of risk factors with AD. Accordingly, we examined the global and age-specific association between APOE genotype and AD by using the A/T/N classification, relying on the cerebrospinal fluid (CSF) levels of ß-amyloid peptide (A, ß-amyloid deposition), phosphorylated tau (T, pathologic tau), and total tau (N, neurodegeneration) to identify patients with AD. METHODS AND FINDINGS: This case-control study included 1,593 white AD cases (55.4% women; mean age 72.8 [range = 44-96] years) with abnormal values of CSF biomarkers from nine European memory clinics and the American Alzheimer's Disease Neuroimaging Initiative (ADNI) study. A total of 11,723 dementia-free controls (47.1% women; mean age 65.6 [range = 44-94] years) were drawn from two longitudinal cohort studies (Whitehall II and Three-City), in which incident cases of dementia over the follow-up were excluded from the control population. Odds ratio (OR) and population attributable fraction (PAF) for AD associated with APOE genotypes were determined, overall and by 5-year age categories. In total, 63.4% of patients with AD and 22.6% of population controls carried at least one APOE ε4 allele. Compared with non-ε4 carriers, heterozygous ε4 carriers had a 4.6 (95% confidence interval 4.1-5.2; p < 0.001) and ε4/ε4 homozygotes a 25.4 (20.4-31.2; p < 0.001) higher OR of AD in unadjusted analysis. This association was modified by age (p for interaction < 0.001). The PAF associated with carrying at least one ε4 allele was greatest in the 65-70 age group (69.7%) and weaker before 55 years (14.2%) and after 85 years (22.6%). The protective effect of APOE ε2 allele for AD was unaffected by age. Main study limitations are that analyses were based on white individuals and AD cases were drawn from memory centers, which may not be representative of the general population of patients with AD. CONCLUSIONS: In this study, we found that AD diagnosis based on biomarkers was associated with APOE ε4 carrier status, with a higher OR than previously reported from studies based on only clinical AD criteria. This association differs according to age, with the strongest effect at 65-70 years. These findings highlight the need for early interventions for dementia prevention to mitigate the effect of APOE ε4 at the population level.


Asunto(s)
Envejecimiento/líquido cefalorraquídeo , Envejecimiento/genética , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/genética , Apolipoproteína E4/líquido cefalorraquídeo , Apolipoproteína E4/genética , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad
10.
Materials (Basel) ; 13(16)2020 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-32781723

RESUMEN

BACKGROUND: Triethylene glycol dimethacrylate (TEGDMA) monomers released from resin matrix are toxic to dental pulp cells, induce apoptosis, oxidative stress and decrease viability. Recently, mitochondrial complex I (CI) was identified as a potential target of TEGDMA. In isolated mitochondria supported by CI, substrates oxidation and ATP synthesis were inhibited, reactive oxygen species production was stimulated. Contrary to that, respiratory Complex II was not impaired by TEGDMA. The beneficial effects of electron carrier compound methylene blue (MB) are proven in many disease models where mitochondrial involvement has been detected. In the present study, the bioenergetic effects of MB on TEGDMA-treated isolated mitochondria and on human dental pulp stem cells (DPSC) were analyzed. METHODS: Isolated mitochondria and DPSC were acutely exposed to low millimolar concentrations of TEGDMA and 2 µM concentration of MB. Mitochondrial and cellular respiration and glycolytic flux were measured by high resolution respirometry and by Seahorse XF extracellular analyzer. Mitochondrial membrane potential was measured fluorimetrically. RESULTS: MB partially restored the mitochondrial oxidation, rescued membrane potential in isolated mitochondria and significantly increased the impaired cellular O2 consumption in the presence of TEGDMA. CONCLUSION: MB is able to protect against TEGDMA-induced CI damage, and might provide protective effects in resin monomer exposed cells.

12.
Alzheimers Dement ; 16(10): 1438-1447, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32614136

RESUMEN

INTRODUCTION: We developed a prognostic model for overall survival after diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) using data from a German surveillance study. METHODS: We included 1226 sCJD cases (median age 66 years, range 19-89 years; 56.8% women with information on age, sex, codon 129 genotype, 14-3-3 in the cerebrospinal fluid (CSF), and CSF tau concentrations. The prognostic accuracy for overall survival was measured by the c statistics of multivariable Cox proportional hazard models. A score chart was derived to predict 6-month survival and median survival time. RESULTS: A model containing age, sex, codon 129 genotype, and CSF tau (with two-way interactions) was selected as the model with the highest c statistic (0.686, 95% confidence interval: 0.665-0.707) in a cross-validation approach. DISCUSSION: We developed the first prognostic model for overall survival of sCJD patients based on readily available information only. The developed score chart serves as a hands-on prediction tool for clinical practice.

13.
Emerg Infect Dis ; 26(8)2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32687038

RESUMEN

We investigated sporadic Creutzfeldt-Jakob disease (sCJD) among physicians in Germany by analyzing occupational information of patients with sCJD recorded by the German CJD Surveillance Unit (1993-2005; 1,250 patients, of whom 4 [0.32%] were physicians) and the National Reference Center for Human Spongiform Encephalopathies (2006-2016; 1,491 patients, of whom 13 [0.87%] were physicians). Among the physicians, we did not identify any neurologists, neurosurgeons, psychiatrists, or pathologists. A cumulative sum test showed an increase in reported physicians over time. Data for 2017-2018 indicated an increased rate of physicians among all notified sCJD cases (5/239 [2.1%]) when we used the total population of Germany as control group. Our data suggest the possibility of an increased risk for sCJD among physicians in Germany. However, we can only speculate about the reasons, and larger multinational studies are needed to replicate the finding and to clarify whether this finding is a general or a country-specific phenomenon.

14.
J Neurol ; 267(9): 2567-2581, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32372181

RESUMEN

BACKGROUND: Differential diagnosis of neurodegenerative dementia is currently supported by biomarkers including cerebrospinal fluid (CSF) tests. Among them, CSF total-tau (t-tau), phosphorylated tau (p-tau) and ß-amyloid42 (Aß42) are considered core biomarkers of neurodegeneration. In the present work, we hypothesize that simultaneous assessment of these biomarkers together with CSF α-synuclein (α-syn) will significantly improve the differential diagnostic of Alzheimer's disease and other dementias. To that aim, we characterized the analytical and clinical performance of a new tetra-plex immunoassay that simultaneously quantifies CSF Aß42, t-tau, p-tau and α-syn in the differential diagnosis of neurodegenerative dementia. METHODS: Biomarkers' concentrations were measured in neurological controls (n = 38), Alzheimer's disease (n = 35), Creutzfeldt-Jakob disease (n = 37), vascular dementia (n = 28), dementia with Lewy bodies/Parkinson's disease dementia (n = 27) and frontotemporal dementia (n = 34) using the new tetra-plex assay and established single-plex assays. Biomarker's performance was evaluated and diagnostic accuracy in the discrimination of diagnostic groups was determined using partial least squares discriminant analysis. RESULTS: The tetra-plex assay presented accuracies similar to individual single-plex assays with acceptable analytical performance. Significant correlations were observed between tetra-plex and single-plex assays. Using partial least squares discriminant analysis, Alzheimer's disease and Creutzfeldt-Jakob disease were well differentiated, reaching high accuracies in the discrimination from the rest of diagnostic groups. CONCLUSIONS: The new tetra-plex assay coupled with multivariate analytical approaches becomes a valuable asset for the differential diagnosis of neurodegenerative dementia and related applications.

15.
Nat Commun ; 11(1): 619, 2020 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-32001681

RESUMEN

The clinical diagnosis of vascular dementia (VaD) is based on imaging criteria, and specific biochemical markers are not available. Here, we investigated the potential of cerebrospinal fluid (CSF) lipocalin 2 (LCN2), a secreted glycoprotein that has been suggested as mediating neuronal damage in vascular brain injuries. The study included four independent cohorts with a total n = 472 samples. LCN2 was significantly elevated in VaD compared to controls, Alzheimer's disease (AD), other neurodegenerative dementias, and cognitively unimpaired patients with cerebrovascular disease. LCN2 discriminated VaD from AD without coexisting VaD with high accuracy. The main findings were consistent over all cohorts. Neuropathology disclosed a high percentage of macrophages linked to subacute infarcts, reactive astrocytes, and damaged blood vessels in multi-infarct dementia when compared to AD. We conclude that CSF LCN2 is a promising candidate biochemical marker in the differential diagnosis of VaD and neurodegenerative dementias.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Trastornos Cerebrovasculares/diagnóstico , Demencia Vascular/diagnóstico , Lipocalina 2/líquido cefalorraquídeo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Biomolecules ; 10(2)2020 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-32059611

RESUMEN

Human prion diseases are classified into sporadic, genetic, and acquired forms. Within this last group, iatrogenic Creutzfeldt-Jakob disease (iCJD) is caused by human-to-human transmission through surgical and medical procedures. After reaching an incidence peak in the 1990s, it is believed that the iCJD historical period is probably coming to an end, thanks to lessons learnt from past infection sources that promoted new prion prevention and decontamination protocols. At this point, we sought to characterise the biomarker profile of iCJD and compare it to that of sporadic CJD (sCJD) for determining the value of available diagnostic tools in promptly recognising iCJD cases. To that end, we collected 23 iCJD samples from seven national CJD surveillance centres and analysed the electroencephalogram and neuroimaging data together with a panel of seven CSF biomarkers: 14-3-3, total tau, phosphorylated/total tau ratio, alpha-synuclein, neurofilament light, YKL-40, and real-time quaking induced conversion of prion protein. Using the cut-off values established for sCJD, we found the sensitivities of these biomarkers for iCJD to be similar to those described for sCJD. Given the limited relevant information on this issue to date, the present study validates the use of current sCJD biomarkers for the diagnosis of future iCJD cases.

17.
BMC Oral Health ; 20(1): 19, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31973705

RESUMEN

BACKGROUND: The purpose of this research was to investigate the effects of disinfection and three different sterilization methods on the dimensional changes and mechanical properties of three-dimensional (3D) printed surgical guide for implant therapy. The objective was to assess the effects of sterilization procedures in 3D printed drill guide templates with destructive and non-destructive material testing. METHODS: Fifteen identical drill guide templates were produced using a 3D printer. The surgical guides were classified into five groups: three controls, three disinfected (4% Gigasept®, 60 min), three plasma sterilized, three autoclave sterilized (+ 1 bar, 121 °C, 20 min), and three autoclave sterilized (+ 2 bar, 134 °C, 10 min). The templates were digitalized with a Steinbichler SCAN ST 3D scanner. Length was measured under an SZX16 stereomicroscope. A scanning electron microscope was used to study the surface morphology of the drill templates. The hardness, and flexural and compressive strength were measured to assess any changes in the physical characteristics of the material caused by sterilization. The drill guide templates were also examined with a Dage XiDAT 6600 X-ray. During the X-ray examinations, the following parameters were used: 100 kV voltage, 128 AVG averaging, 0.8 W power. One-way analysis of variance (ANOVA) was used to detect the difference between groups. RESULTS: Evaluation of the hardness measurements of the various specimens shows that the hardness of the material was not changed by the plasma sterilization (p = 0.0680), steam sterilization on 121 °C (p = 0.6033) or disinfection process (p = 0.1399). The statistical analysis revealed significant difference in hardness strength of the autoclave sterilized (134 °C) specimens (p = 0.0002). There was no significant difference between the goups regarding the scanning electron microscopic and stereomicroscopic examinations. There was no significant difference regarding the X-ray visibility of the templates to the effect of the disinfection (p = 0.7844), plasma sterilization (p = 0.4091) and steam sterilization on 121 °C (p = 0.9277) and steam sterilization on 131 °C (p = 0.093). The effect of the sterilization was the same in case of both flexural and compressive strength of the material. CONCLUSIONS: Our findings indicate that plasma sterilization and steam sterilization at 121 °C were both suitable for sterilizing the tested 3D printed surgical guides.


Asunto(s)
Implantación Dental/instrumentación , Materiales Dentales/química , Desinfección , Impresión Tridimensional , Vapor , Esterilización/métodos , Cirugía Asistida por Computador/instrumentación , Diseño Asistido por Computadora , Calor , Humanos , Ensayo de Materiales , Proyectos Piloto
18.
J Craniofac Surg ; 31(1): 15-27, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31369496

RESUMEN

The craniofacial region is anatomically complex and is of critical functional and cosmetic importance, making reconstruction challenging. The limitations of current surgical options highlight the importance of developing new strategies to restore the form, function, and esthetics of missing or damaged soft tissue and skeletal tissue in the face and cranium. Regenerative medicine (RM) is an expanding field which combines the principles of tissue engineering (TE) and self-healing in the regeneration of cells, tissues, and organs, to restore their impaired function. RM offers many advantages over current treatments as tissue can be engineered for specific defects, using an unlimited supply of bioengineered resources, and does not require immunosuppression. In the craniofacial region, TE and RM are being increasingly used in preclinical and clinical studies to reconstruct bone, cartilage, soft tissue, nerves, and blood vessels. This review outlines the current progress that has been made toward the engineering of these tissues for craniofacial reconstruction and facial esthetics.


Asunto(s)
Cara/cirugía , Medicina Regenerativa , Cráneo/cirugía , Ingeniería de Tejidos , Humanos , Procedimientos Quirúrgicos Reconstructivos , Cirugía Plástica
19.
J Neurol ; 267(2): 543-550, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31701333

RESUMEN

Cerebrospinal fluid (CSF) non-phosphorylated tau (non-p-tau) is increased in sporadic Creutzfeldt-Jakob disease (CJD), but its accuracy in the differential diagnosis has not been previously established. Here, we first used a retrospective cohort of non-CJD (n = 135) and CJD (n = 137) cases to determine the optimal cutoff point for the discrimination of CJD cases. Next, we prospectively quantified non-p-tau and 14-3-3 protein in a cohort of 1427 cases received for CSF testing at the German National Reference Center for transmissible spongiform encephalopathies. Among them, 36 were subsequently diagnosed as CJD. The diagnostic accuracy of both proteins discriminating CJD cases was evaluated. Using a cutoff of 650 pg/mL, non-p-tau displayed 94.39% accuracy in discriminating CJD cases, while 92.92% accuracy was achieved by 14-3-3 using a cutoff of 20,000 AU/mL. Diagnostic test evaluation for both proteins showed a slightly better performance of non-p-tau compared to 14-3-3. The two biomarkers' concentrations showed a significant positive correlation, both in the total population and in CJD cases (p < 0.001). Finally, the analysis of CSF non-p-tau concentrations when undergoing pre-analytical factors showed high stability in front of temperature storage and freeze/thaw cycles. Therefore, we conclude that when used in the appropriate clinical context of a prion disease surveillance center, non-p-tau is a highly sensitive and specific diagnostic marker for CJD.


Asunto(s)
Proteínas 14-3-3/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquídeo , Síndrome de Creutzfeldt-Jakob/diagnóstico , Proteínas tau/líquido cefalorraquídeo , Diagnóstico Diferencial , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Sensibilidad y Especificidad
20.
Molecules ; 24(20)2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31615035

RESUMEN

Poly(ethyleneimine) (PEI) is a weakly basic, synthetic, polycationic polymer, due to the presence of primary, secondary, and tertiary amino groups. The amino groups are responsible for the variety of applications of PEI (e.g., transfection, bioimaging, solar cell, etc.). Our study presents some new and reproducible methods for the quantification of molecular or mass concentration of highly branched PEI of different molecular weights (800-2000-25,000-750,000 MW PEI). In the course of the direct method, spectrophotometry and fluorometry were applied to determine the absorption and fluorescence of PEI dilution series. An increase in the MW at the same concentration produces a higher count number because of the higher number of amino groups in PEI molecules. The character of increment in fluorescence intensity is essentially different in the case of mass concentrations and molar concentrations. The increment of the fluorescence intensity related to the molar concentration is non-linear. In the case of mass concentration, the slope is linear. Moreover, their fluorescence is enhanced with the decrease in pH values. The spectrophotometry is a reliable method for measuring the quantity of PEI molecules in solution. Our data help in recognizing the detailed properties of PEI in dendrimer research.


Asunto(s)
Dendrímeros/química , Fluorescencia , Polietileneimina/química , Aziridinas/química , Cationes/química , Concentración de Iones de Hidrógeno , Peso Molecular , Polímeros/química
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