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1.
Artigo em Inglês | MEDLINE | ID: mdl-34501710

RESUMO

This work evaluates the impact of the COVID-19 pandemic on Czech dentistry from March 2020 to March 2021. The assessment was based on questionnaires filled out by 3674 Czech dentists representing 42.6% of practicing dentists in the country. During March-May, 2020 (the first COVID-19 wave), 90.7% of dental practices remained open; however, only 22.8% of the practices continued to operate with no changes, 46.5% had fewer patients, 21.4% treated only acute cases, and 3.8% were closed. During September 2020-May 2021 (the second wave of COVID-19), 96.1% of dental practices remained open, 60.8% operated with no changes, 34.5% had fewer patients, 0.8% treated only acute cases, and 0.5% were closed. The reasons leading to the closure of Czech dental practices during the whole pandemic were a shortage of personal protective equipment (50.5%), a COVID-19 outbreak in the workplace (24.5%), fear of a possible self-infection (24.0%), and quarantine (20.5%). The time range of Czech dental practices closure during the whole pandemic was: 1-2 weeks (49.9%), 2-4 weeks (21.2%), and >1 month (0.8%). The greatest professional difficulties of Czech dentists during the pandemic were crisis operating management (55%), health safety and hygiene concerns (21%), shortage of personal protective equipment (21%), and difficulty working with the protective equipment (15%). In addition, 47.3% of dentists also observed a declining interest in preventive dental care, and 16.9% of them observed worse oral care of patients. These results show that despite the lack of protective equipment, dental care was maintained throughout the pandemic. Additionally, the pandemic negatively affected the patients' approach to dental care, indicating a deterioration in oral health as a possible delayed outcome of the COVID-19 pandemic.


Assuntos
COVID-19 , Pandemias , Estudos Transversais , República Tcheca/epidemiologia , Odontologia , Odontólogos , Humanos , SARS-CoV-2
2.
Microorganisms ; 9(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34361890

RESUMO

Nematodes represent a diverse and ubiquitous group of metazoans in terrestrial environments. They feed on bacteria, fungi, plants, other nematodes or parasitize a variety of animals and hence may be considered as active members of many food webs. Deadwood is a structural component of forest ecosystems which harbors many niches for diverse biota. As fungi and bacteria are among the most prominent decomposing colonizers of deadwood, we anticipated frequent and diverse nematode populations to co-occur in such ecosystems. However, knowledge about their ability to colonize this habitat is still limited. We applied DNA-based amplicon sequencing (metabarcoding) of the 18S rRNA gene to analyze nematode communities in sapwood and heartwood of decaying logs from 13 different tree species. We identified 247 nematode ASVs (amplicon sequence variants) from 27 families. Most of these identified families represent bacterial and fungal feeders. Their composition strongly depended on tree species identity in both wood compartments. While pH and water content were the only wood properties that contributed to nematodes' distribution, co-occurring fungal and prokaryotic (bacteria and archaea) α- and ß-diversities were significantly related to nematode communities. By exploring thirteen different tree species, which exhibit a broad range of wood characteristics, this study provides first and comprehensive insights into nematode diversity in deadwood of temperate forests and indicates connectivity to other wood-inhabiting organisms.

3.
Biomolecules ; 11(8)2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34439823

RESUMO

Alveolar osteitis (AO) is a common complication following the extraction of the teeth, particularly the lower third molars. It starts within a few days after the extraction and manifests mainly as pain in the extraction site. Several strategies of treatment are available in order to relieve pain and heal the extraction wound. Recently, a novel medical device combining hyaluronic acid (HA) and octenidine (OCT) was introduced for the treatment of AO. This series of case reports aims to summarize the initial clinical experiences with this new device and to highlight factors possibly interfering with this treatment. The medical documentation of five patients with similar initial situations treated for AO with HA + OCT device was analyzed in detail. Smoking and previous treatment with Alveogyl (Septodont, Saint-Maur-des-Fossés, France) were identified as factors interfering with the AO treatment with the HA + OCT device. In three patients without these risk factors, the treatment led to recovery within two or three days. The patient pretreated with Alveogyl and the smoker required six and seven applications of the HA + OCT device, respectively. According to these initial observations, it seems smoking and previous treatment with Alveogyl prolong the treatment of AO using the HA + OCT device that, in turn, shows a rapid effect if these risk factors are not present.


Assuntos
Alvéolo Seco/tratamento farmacológico , Ácido Hialurônico/uso terapêutico , Iminas/uso terapêutico , Dor/tratamento farmacológico , Piridinas/uso terapêutico , Cicatrização/efeitos dos fármacos , Adolescente , Adulto , Creosoto/efeitos adversos , Combinação de Medicamentos , Alvéolo Seco/etiologia , Alvéolo Seco/fisiopatologia , Alvéolo Seco/cirurgia , Equipamentos e Provisões , Feminino , Humanos , Hidrocarbonetos Iodados/efeitos adversos , Pessoa de Meia-Idade , Dente Molar/cirurgia , Dor/etiologia , Dor/fisiopatologia , Dor/cirurgia , Fatores de Risco , Fumar/efeitos adversos , Extração Dentária/efeitos adversos , Resultado do Tratamento , Cicatrização/fisiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-34202699

RESUMO

This work provides a narrative review covering evidence-based recommendations for pericoronitis management (Part A) and a systematic review of antibiotic prescribing for pericoronitis from January 2000 to May 2021 (Part B). Part A presents the most recent, clinically significant, and evidence-based guidance for pericoronitis diagnosis and proper treatment recommending the local therapy over antibiotic prescribing, which should be reserved for severe conditions. The systematic review includes publications analyzing sets of patients treated for pericoronitis and questionnaires that identified dentists' therapeutic approaches to pericoronitis. Questionnaires among dentists revealed that almost 75% of them prescribed antibiotics for pericoronitis, and pericoronitis was among the top 4 in the frequency of antibiotic use within the surveyed diagnoses and situations. Studies involving patients showed that antibiotics were prescribed to more than half of the patients with pericoronitis, and pericoronitis was among the top 2 in the frequency of antibiotic use within the monitored diagnoses and situations. The most prescribed antibiotics for pericoronitis were amoxicillin and metronidazole. The systematic review results show abundant and unnecessary use of antibiotics for pericoronitis and are in strong contrast to evidence-based recommendations summarized in the narrative review. Adherence of dental professionals to the recommendations presented in this work can help rapidly reduce the duration of pericoronitis, prevent its complications, and reduce the use of antibiotics and thus reduce its impact on patients' quality of life, healthcare costs, and antimicrobial resistance development.


Assuntos
Antibacterianos , Pericoronite , Antibacterianos/efeitos adversos , Odontologia , Odontólogos , Humanos , Prescrição Inadequada , Pericoronite/tratamento farmacológico , Padrões de Prática Odontológica , Qualidade de Vida
5.
Acta Medica (Hradec Kralove) ; 64(2): 101-107, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34331430

RESUMO

Iatrogenic mandible fracture is a rare complication of a tooth extraction with an incidence between 0.0033-0.0034%. This study retrospectively analyzes a total of 8 patients who underwent lower molar extraction associated with mandible fracture during tooth removal in the period from April 2006 to March 2019. The assessed parameters were age and sex of patients, method of tooth extraction, side distribution of fracture, type of extracted tooth, the position of a lower third molar, presence of bone pathological lesion formed in connection with a tooth, displacement of bone fragments, and sensory impairment in the innervation area of the mental nerve. The position and impaction of the lower third molars were evaluated according to Pell and Gregory's classification and Winter's classification. One fracture was left-sided, and 7 fractures were right-sided. In 6 cases, Winter's extraction elevator was used. In 7 patients, the mandible fracture was treated surgically by performing stable osteosynthesis with the plates and screws. One patient was treated conservatively. This work analyzes the causes of iatrogenic mandible fractures and provides recommendations to reduce the risk of their occurrence.


Assuntos
Fraturas Mandibulares/etiologia , Dente Serotino/cirurgia , Extração Dentária/efeitos adversos , Feminino , Humanos , Doença Iatrogênica , Masculino , Fraturas Mandibulares/terapia , Estudos Retrospectivos
6.
Artigo em Inglês | MEDLINE | ID: mdl-34300119

RESUMO

Musculoskeletal disorders (MSDs) frequently occur among dental practitioners and present a significant occupational burden with an early onset in the dentists' career. This study aimed to analyze the five-year development of self-reported overall MSDs among the dentistry students during the course of their studies and to assess the possible influence of the risk as well as protective factors. The questionnaire inquiry was performed among the first-year dentistry students, regarding the occurrence of MSDs and the presence of potential risk and protective factors. The same students were followed, and they filled in the same questionnaire in the middle and at the end of their studies. A total of 73 dentistry students and 28 general medicine students participated. The occurrence of the overall MSDs statistically significantly increased from 30.1% at the beginning of the first year to 45.2% at the end of the fifth year among the dentistry students. The top-level sport was statistically significantly associated with the higher occurrence of MSDs in the fifth year and with the development of new MSDs between the first and the fifth year. This longitudinal prospective evaluation showed a significant increase in the MSDs occurrence among the dentistry students during their studies.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Odontologia , Odontólogos , Ergonomia , Humanos , Doenças Musculoesqueléticas/epidemiologia , Doenças Profissionais/epidemiologia , Papel Profissional , Estudos Prospectivos , Fatores de Risco
7.
Biomolecules ; 11(3)2021 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804786

RESUMO

Telomeres are repetitive nucleoprotein DNA sequences that shorten with each cell division. The stem cells activate telomerase to compensate for the telomere loss. This study aimed to evaluate the effect of cultivation passaging on the relative telomere length and proliferation capacity of dental pulp stem cells. We used ten dental pulp stem cell (DPSC) lineages stored for 12 months using uncontrolled-rate freezing to reach the study's goal. We analyzed their proliferation rate, phenotype using flow cytometry, multipotency, and relative telomere length using a qPCR analysis. We determined the relative telomere length in the added study by performing analysis after one, two, and three weeks of cultivation with no passaging. We documented the telomere attrition with increasing passaging. The shorter the relative telomere length, the lower reached population doublings, and longer population doubling time were observed at the end of the cultivation. We observed the telomere prolongation in DPSCs cultivated for two weeks with no passaging in the added subsequent study. We concluded that excessive proliferation demands on DPSCs during in vitro cultivation result in telomere attrition. We opened the theory that the telomerase might be more efficient during cell cultivation with no passaging. This observation could help in preserving the telomere length during ex vivo DPSC expansion.


Assuntos
Proliferação de Células/fisiologia , Polpa Dentária/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Telômero/genética , Proliferação de Células/genética , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Fenótipo , Reação em Cadeia da Polimerase , Telomerase/metabolismo
8.
Sensors (Basel) ; 21(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918494

RESUMO

A signal transmitted in an Underwater Acoustic Communication (UAC) system operating in a shallow-water channel suffers from strong time dispersion due to multipath propagation. This causes the Inter-Symbol Interference (ISI) observed in the received signal, which significantly limits the communication system's reliability and transmission rate. In such propagation conditions, the Direct-Sequence Spread Spectrum (DSSS) method is one of the solutions that make reliable data transmission possible. In systems with one-to-one communication, it ensures communication with a satisfactory Bit Error Rate (BER). Additionally, it makes it possible to implement the Code-Division Multiple Access (CDMA) protocol in underwater acoustic networks. This paper presents the results of simulation and experimental communication tests on a DSSS-based UAC system using three types of spreading sequence, namely m-sequences, Kasami codes and Gold codes, and occupying different bandwidths from 1 kHz to 8 kHz around a carrier frequency equal to 30 kHz. The UAC channel was simulated by impulse responses calculated by the virtual sources method and the UAC chanel models available in the Watermark simulator. The experimental tests were conducted in a model pool. Based on the obtained results, a transmission rate was estimated, which is possible to achieve in strong multipath propagation conditions, assuming reliability expressed as BER less than 0.001.

9.
Int J Mol Sci ; 22(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922674

RESUMO

Dental pulp stem cells (DPSCs) are a type of easily accessible adult mesenchymal stem cell. Due to their ease of access, DPSCs show great promise in regenerative medicine. However, the tooth extractions from which DPSCs can be obtained are usually performed at a period of life when donors would have no therapeutic need of them. For this reason, it is imperative that successful stem cell storage techniques are employed so that these cells remain viable for future use. Any such techniques must result in high post-thaw stem cell recovery without compromising stemness, proliferation, or multipotency. Uncontrolled-rate freezing is not a technically or financially demanding technique compared to expensive and laborious controlled-rate freezing techniques. This study was aimed at observing the effect of uncontrolled-rate freezing on DPSCs stored for 6 and 12 months. Dimethyl sulfoxide at a concentration of 10% was used as a cryoprotective agent. Various features such as shape, proliferation capacity, phenotype, and multipotency were studied after DPSC thawing. The DPSCs did not compromise their stemness, viability, proliferation, or differentiating capabilities, even after one year of cryopreservation at -80 °C. After thawing, they retained their stemness markers and low-level expression of hematopoietic markers. We observed a size reduction in recovery DPSCs after one year of storage. This observation indicates that DPSCs can be successfully used in potential clinical applications, even after a year of uncontrolled cryopreservation.


Assuntos
Diferenciação Celular , Criopreservação/métodos , Crioprotetores/farmacologia , Polpa Dentária/citologia , Células-Tronco/citologia , Adolescente , Proliferação de Células , Células Cultivadas , Polpa Dentária/efeitos dos fármacos , Feminino , Humanos , Masculino , Células-Tronco/efeitos dos fármacos
10.
BMC Health Serv Res ; 21(1): 341, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853593

RESUMO

BACKGROUND: Many hospitals seek to increase patient safety through interprofessional team-trainings. Accordingly, these trainings aim to strengthen important key aspects such as safety culture and communication. This study was designed to investigate if an interprofessional team-training, administered to a relatively small group of nurses and physicians would promote a change in healthcare professionals' perceptions on safety culture and communication practices throughout the hospital. We further sought to understand which safety culture aspects foster the transfer of trained communication practices into clinical practice. METHODS: We conducted a pre-post survey study using six scales to measure participants' perceptions of safety culture and communication practices. Mean values were compared according to profession and participation in training. Using multiple regression models, the relationship between safety culture and communication practices was determined. RESULTS: Before and after the training, we found high mean values for all scales. A significant, positive effect was found for the communication practices of the physicians. Participation in the training sessions played a variably relevant role in the communication practices. In addition, the multiple regression analyses showed that specific safety culture aspects have a cross-professional influence on communication practices in the hospital. CONCLUSIONS: This study suggest that interprofessional team-trainings of a small group of professionals can successfully be transferred into clinical practice and indicates the importance of safety culture aspects for such transfer processes. Thus, we recommend the consideration of safety culture aspects before starting a training intervention.


Assuntos
Médicos , Comunicação , Humanos , Relações Interprofissionais , Equipe de Assistência ao Paciente , Percepção , Gestão da Segurança , Inquéritos e Questionários
11.
Rep Prog Phys ; 84(1): 012403, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33176284

RESUMO

Quantum fluctuations can stabilize Bose-Einstein condensates (BEC) against the mean-field collapse. Stabilization of the condensate has been observed in quantum degenerate Bose-Bose mixtures and dipolar BECs. The fine-tuning of the interatomic interactions can lead to the emergence of two new states of matter: liquid-like self-bound quantum droplets and supersolid crystals formed from these droplets. We review the properties of these exotic states of matter and summarize the experimental progress made using dipolar quantum gases and Bose-Bose mixtures. We conclude with an outline of important open questions that could be addressed in the future.

12.
J Arthroplasty ; 36(1): 379-386, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32826141

RESUMO

BACKGROUND: Computed tomography (CT) scan is the standard for assessment of femoral torsion. This observational study was conducted to evaluate the comparability of the EOS radiation dose scanning system (EOS imaging, Paris, France) and the CT scan in patients with suspected torsional malalignment of the femur. METHODS: Patients with suspected torsional malalignment of the femur were included in a study for surgical planning. The primary endpoint was to compare the 3-dimensional radiological (EOS) imaging system with the CT scan to determine femoral anteversion (AV) angle. Three independent raters performed measurements. Comparability of CT scan and EOS values was assessed by Pearson correlation, t test, interobserver reliability, and intraobserver reliability (Cronbach alpha). RESULTS: About 34 femora were examined. Interobserver reliability/intraobserver reliability was 0.911 of 0.955 for EOS and 0.934 of 0.934 for CT scan. EOS system revealed an AV angle of 12.2° ± 10.0° (-15.0° to 32.0°). CT examinations showed an AV angle of 12.6° ± 9.2° (-3.2° to 35.6°). About 11 hips featured physiological AV, 14 hips showed decreased AV (<10°) or retroversion (<0°), and 9 hips showed increased AV (>20°). Overall, a strong Pearson correlation of τ = 0.855 and a highly significant correlation in the t test for both methods was seen. In patients with decreased AV, retroversion, or increased AV, Pearson correlation only resulted in a moderate/low correlation of τ = 0.495 and τ = 0.292. The t test showed no significant correlation at malrotation. CONCLUSION: In torsional malalignment, EOS does not have correlation with CT measurements. In contrast to CT scan, EOS allows femoral torsion measurement independent of legs' positioning.


Assuntos
Fêmur , Tomografia Computadorizada por Raios X , Fêmur/diagnóstico por imagem , França , Humanos , Exame Físico , Reprodutibilidade dos Testes
13.
Biomolecules ; 11(1)2020 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379324

RESUMO

Hyaluronic acid (HA) and dental pulp stem cells (DPSCs) are attractive research topics, and their combined use in the field of tissue engineering seems to be very promising. HA is a natural extracellular biopolymer found in various tissues, including dental pulp, and due to its biocompatibility and biodegradability, it is also a suitable scaffold material. However, low molecular weight (LMW) fragments, produced by enzymatic cleavage of HA, have different bioactive properties to high molecular weight (HMW) HA. Thus, the impact of HA must be assessed separately for each molecular weight fraction. In this study, we present the effect of three LMW-HA fragments (800, 1600, and 15,000 Da) on DPSCs in vitro. Discrete biological parameters such as DPSC viability, morphology, and cell surface marker expression were determined. Following treatment with LMW-HA, DPSCs initially presented with an acute reduction in proliferation (p < 0.0016) and soon recovered in subsequent passages. They displayed significant size reduction (p = 0.0078, p = 0.0019, p = 0.0098) while maintaining high expression of DPSC markers (CD29, CD44, CD73, CD90). However, in contrast to controls, a significant phenotypic shift (p < 0.05; CD29, CD34, CD90, CD106, CD117, CD146, CD166) of surface markers was observed. These findings provide a basis for further detailed investigations and present a strong argument for the importance of HA scaffold degradation kinetics analysis.


Assuntos
Proliferação de Células/efeitos dos fármacos , Polpa Dentária/crescimento & desenvolvimento , Ácido Hialurônico/farmacologia , Células-Tronco/citologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Polpa Dentária/efeitos dos fármacos , Humanos , Peso Molecular , Células-Tronco/efeitos dos fármacos , Engenharia Tecidual
14.
Langenbecks Arch Surg ; 405(8): 1233-1241, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33084924

RESUMO

INTRODUCTION: Postoperative pancreatic fistula (POPF) represents the most common form of morbidity after distal pancreatectomy (DP). The aim of this study was to illustrate an innovative technique of irrigation and passive drainage to reduce clinically relevant POPF (CR-POPF) incidence in high-risk patients undergoing DP. MATERIAL AND METHODS: Twelve consecutive high-risk patients received irrigation and passive drainage of the pancreatic stump with a Salem sump drainage after DP. The Salem sump was irrigated with 100 ml/h of Ringer solution for 2 postoperative days (POD). In the case of low-drain amylase and lipase levels on POD 3, the irrigation was reduced to 50 ml/h. Persistence of low-drain pancreatic enzymes on POD 4 allowed for interruption of irrigation and subsequent removal of drainage from POD 7 onward in the absence of evidence of any pancreatic fistula. RESULTS: Overall, 16.6% of the patients experienced a grade 3 or higher surgical complication. We experienced only one case of POPF: the fistula was classified as grade B and it was managed with radiologic drainage of the fluid collection. We did not experience any case of re-operation nor in-hospital mortality. CONCLUSIONS: Irrigation with passive drainage of the pancreatic stump after DP is an interesting approach for CR-POPF prevention in high-risk patients.


Assuntos
Pancreatectomia , Fístula Pancreática , Drenagem , Humanos , Pâncreas/cirurgia , Pancreatectomia/efeitos adversos , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Fístula Pancreática/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos
15.
J Appl Crystallogr ; 53(Pt 5): 1212-1216, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33117108

RESUMO

The Ge/Si(001) system has been analysed by grazing-incidence X-ray diffraction on a standard laboratory X-ray diffraction tool. A periodic array of interfacial edge dislocations forms a coincidence site lattice (CSL) which yields equidistantly spaced satellite peaks close to Bragg peaks of the Ge layer and Si substrate. The diffraction behaviour of the CSL was analysed using 2θ/φ scans along [100], [110] and [310] directions as well as azimuthal φ scans which revealed a 90° angular symmetry of the CSL. Additionally, different layer thicknesses, from 10 to 580 nm, were analysed, focusing on the dependence of layer thickness on the glancing angles of the satellite peaks. This method provides the ability to analyse whether or not epitaxially grown layers exhibit a periodic array of dislocations, and gain information about the orientation of the interfacial edge dislocations.

16.
Nat Commun ; 11(1): 4263, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848132

RESUMO

Eukaryotic DNA replication initiation relies on the origin recognition complex (ORC), a DNA-binding ATPase that loads the Mcm2-7 replicative helicase onto replication origins. Here, we report cryo-electron microscopy (cryo-EM) structures of DNA-bound Drosophila ORC with and without the co-loader Cdc6. These structures reveal that Orc1 and Orc4 constitute the primary DNA binding site in the ORC ring and cooperate with the winged-helix domains to stabilize DNA bending. A loop region near the catalytic Walker B motif of Orc1 directly contacts DNA, allosterically coupling DNA binding to ORC's ATPase site. Correlating structural and biochemical data show that DNA sequence modulates DNA binding and remodeling by ORC, and that DNA bending promotes Mcm2-7 loading in vitro. Together, these findings explain the distinct DNA sequence-dependencies of metazoan and S. cerevisiae initiators in origin recognition and support a model in which DNA geometry and bendability contribute to Mcm2-7 loading site selection in metazoans.


Assuntos
Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Complexo de Reconhecimento de Origem/química , Complexo de Reconhecimento de Origem/metabolismo , Origem de Replicação , Domínio AAA , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Microscopia Crioeletrônica , DNA/química , DNA/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Hidrólise , Proteínas de Manutenção de Minicromossomo/química , Proteínas de Manutenção de Minicromossomo/genética , Proteínas de Manutenção de Minicromossomo/metabolismo , Modelos Moleculares , Complexo de Reconhecimento de Origem/genética , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Origem de Replicação/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
17.
Sci Rep ; 10(1): 7530, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32371994

RESUMO

In the search for highly transparent and non-toxic alternative front layers replacing state-of-the-art CdS in Cu(In,Ga)Se2 thin-film solar cells, alternatives rarely exceed reference devices in terms of efficiency. Full-area ultra-thin aluminium oxide tunnelling layers do not require any contact patterning and thus overcome the main drawback of insulating passivation layers. Even a few monolayers of aluminium oxide can be deposited in a controlled manner by atomic layer deposition, they show excellent interface passivation properties, low absorption, and suitable current transport characteristics on test devices. Depositing a ZnO-based transparent front contact, however, results in extremely poor solar cell performance. The issue is not necessarily a low quality of the alternative front layer, but rather the intricate relation between front layer processing and electronic bulk properties in the absorber layer. We identify three challenges critical for the development of novel front passivation approaches: (i) both Cd and Zn impurities beneficially reduce the high native net dopant concentration in the space charge region, (ii) sputter deposition of ZnO damages the passivation layer resulting in increased interface recombination, (iii) thermal treatments of devices with ZnO layer result in substantial Zn diffusion, which can penetrate the full absorber thickness already at moderate temperatures.

18.
Sci Rep ; 10(1): 8445, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439873

RESUMO

Artificial intelligence (AI) is developing rapidly in the medical technology field, particularly in image analysis. ECG-diagnosis is an image analysis in the sense that cardiologists assess the waveforms presented in a 2-dimensional image. We hypothesized that an AI using a convolutional neural network (CNN) may also recognize ECG images and patterns accurately. We used the PTB ECG database consisting of 289 ECGs including 148 myocardial infarction (MI) cases to develop a CNN to recognize MI in ECG. Our CNN model, equipped with 6-layer architecture, was trained with training-set ECGs. After that, our CNN and 10 physicians are tested with test-set ECGs and compared their MI recognition capability in metrics F1 (harmonic mean of precision and recall) and accuracy. The F1 and accuracy by our CNN were significantly higher (83 ± 4%, 81 ± 4%) as compared to physicians (70 ± 7%, 67 ± 7%, P < 0.0001, respectively). Furthermore, elimination of Goldberger-leads or ECG image compression up to quarter resolution did not significantly decrease the recognition capability. Deep learning with a simple CNN for image analysis may achieve a comparable capability to physicians in recognizing MI on ECG. Further investigation is warranted for the use of AI in ECG image assessment.


Assuntos
Algoritmos , Inteligência Artificial , Bases de Dados Factuais , Aprendizado Profundo , Eletrocardiografia/métodos , Infarto do Miocárdio/diagnóstico , Redes Neurais de Computação , Humanos , Infarto do Miocárdio/diagnóstico por imagem
19.
Eur J Med Res ; 25(1): 5, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183891

RESUMO

BACKGROUND: The prognostic implications of non-sustained ventricular tachycardia (NSVT) and their significance as therapeutic targets in patients without prior sustained ventricular arrhythmias remain undetermined. The aim of this study was to investigate the prognostic significance of asymptomatic NSVT in patients who had primary prevention implantable cardioverter-defibrillator (ICD) implantation due to ischemic or non-ischemic cardiomyopathy (ICM, NICM). METHODS: We enrolled 157 consecutive primary prevention ICD patients without previous appropriate ICD therapy (AIT). Patients were allocated to two groups depending on the presence or absence of NSVT in a 6-month period prior to enrollment. The incidence of AIT and unplanned hospitalization due to decompensated heart failure (HF) were assessed during follow-up. RESULTS: In 51 patients (32%), precedent NSVT was documented. During a median follow-up of 1011 days, AIT occurred in 36 patients (23%) and unplanned HF hospitalization was observed in 32 patients (20%). In precedent NSVT patients, the incidence of AIT and unplanned HF hospitalization was significantly higher as compared to patients without precedent NSVT (AIT: 29/51 [57%] vs. 7/106 [7%], P < 0.001, log-rank; HF hospitalization: 16/51 [31%] vs. 16/106 [15%], P = 0.043, log-rank). Cox-regression demonstrated that precedent NSVT independently predicted AIT (P < 0.0001). In subgroup analyses, precedent NSVT predicted AIT in both ICM and NICM (P < 0.0001, P = 0.020), but predicted HF hospitalization only in patients with ICM (P = 0.0030). CONCLUSIONS: Precedent non-sustained VT in patients with primary prevention ICDs is associated with subsequent appropriate ICD therapies, and is an independent predictor of unplanned heart failure hospitalizations in patients with ischemic cardiomyopathy.


Assuntos
Desfibriladores Implantáveis/estatística & dados numéricos , Insuficiência Cardíaca/complicações , Hospitalização/estatística & dados numéricos , Prevenção Primária/estatística & dados numéricos , Idoso , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Fatores de Risco
20.
Am J Cardiol ; 125(8): 1162-1169, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32087999

RESUMO

The aim of the present study was to determine whether free thyroxine (FT4) and calculated thyroid parameters predict the incidence of ventricular arrhythmias in euthyroid heart failure patients with implantable cardioverter-defibrillators (ICD). In this open-label prospective cohort study, 115 consecutive euthyroid patients (mean age 62.9 ± 1.3 years; 87% male; ischemic cardiomyopathy 63%) scheduled for primary prevention ICD implantation or exchange were enrolled. Serum concentrations of thyrotropin (thyroid-stimulating hormone) and FT4 were measured 1 day before device operation. Primary and secondary end points were defined as occurrence of appropriate ICD therapy (AIT) and cardiovascular death, respectively. During a mean follow-up of 1,191 ± 35 days, 24 patients (21%) experienced AIT, and cardiovascular death was observed in 10 patients (9%). Patients with AIT had higher FT4 concentrations compared with those without AIT (18.9 ± 0.48 vs 16.2 ± 0.22 pmol/L, p <0.001). FT4 was an independent predictor of AIT in an adjusted Cox regression (hazard ratio = 1.47, p <0.001). Kaplan-Meier analysis demonstrated that Jostel's thyroid-stimulating hormone index, reflecting the central component of the hypothalamus-pituitary-thyroid loop, and SPINA-GT as surrogate markers for thyroid's secretory capacity predicted AIT incidences. None of the indices predicted cardiovascular death. In conclusion, FT4 concentration predicts an increased incidence of ventricular arrhythmias in euthyroid patients receiving ICDs for primary prevention. Our data suggest that both impending primary hyperthyroidism and an increased thyroid homeostasis set point may increase the rate of AIT in this patient population.


Assuntos
Cardiomiopatias/terapia , Isquemia Miocárdica/terapia , Taquicardia Ventricular/epidemiologia , Tireotropina/sangue , Tiroxina/sangue , Fibrilação Ventricular/epidemiologia , Idoso , Estimulação Cardíaca Artificial/estatística & dados numéricos , Cardiomiopatias/complicações , Estudos de Coortes , Desfibriladores Implantáveis , Cardioversão Elétrica/estatística & dados numéricos , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Prevenção Primária , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Taquicardia Ventricular/prevenção & controle , Taquicardia Ventricular/terapia , Fibrilação Ventricular/prevenção & controle , Fibrilação Ventricular/terapia
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