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1.
J Neurooncol ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390195

RESUMO

OBJECTIVE: Treatment for malignant gliomas involves multiple disciplines, including neurosurgery, radiation therapy, medical and neuro-oncology, and palliative medicine, with function-preserving neurosurgical tumor removal being crucial. However, real-world data on hospital cases, treatment types, especially regarding surgical approaches, and the associated complication and mortality rates in Germany are lacking. METHODS: We analyzed data on hospital cases involving malignant gliomas (ICD-10-GM code C71) from the German §21 Hospital Remuneration Act, provided by the Institute for the Hospital Remuneration System (InEK GmbH), from 2019 to 2022. Our focus was on neuro-oncological operations defined by the German Cancer Society (DKG) and included specific operation and procedure (OPS) codes. RESULTS: From 2019 to 2022, there were 101,192 hospital cases involving malignant gliomas in Germany. Neurosurgical tumor removal was performed in 27,193 cases (26.9%). Microsurgical techniques were used in 95% of surgeries, intraoperative navigation systems in 84%, fluorescence-guided surgeries in 45.6%, and intraoperative neurophysiological monitoring (IONM) in 46.4%. Surgical or medical complications occurred in 2903 cases (10.7%). The hospital mortality rate was 2.7%. Mortality was significantly higher in patients aged 65 and older (Odds ratio 2.9, p < 0.0001), and lower in cases using fluorescence-guided procedures (Odds ratio 0.8, p = 0.015) and IONM (Odds ratio 0.5, p < 0.0001). CONCLUSIONS: Over the course of 4 years, over 100,000 hospital cases involving adult patients diagnosed with malignant gliomas were treated in Germany, with 27,193 cases undergoing tumor removal using various modern surgical techniques. The hospital mortality rate was 2.7%.

2.
Microbiol Spectr ; : e0124624, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361873

RESUMO

Mycobacterium tuberculosis (Mtb), the pathogen responsible for tuberculosis (TB), is the leading cause of bacterial disease-related death worldwide. Current antibiotic regimens for the treatment of TB remain dated and suffer from long treatment times as well as the development of drug resistance. As such, the search for novel chemical modalities that have selective or potent anti-Mtb properties remains an urgent priority, particularly against multidrug-resistant (MDR) Mtb strains. Herein, we design and synthesize 35 novel benzo[c]phenanthridine derivatives (BPDs). The two most potent compounds, BPD-6 and BPD-9, accumulated within the bacterial cell and exhibited strong inhibitory activity (MIC90 ~2 to 10 µM) against multiple Mycobacterium strains while remaining inactive against a range of other Gram-negative and Gram-positive bacteria. BPD-6 and BPD-9 were also effective in reducing Mtb survival within infected macrophages, and BPD-9 reduced the burden of Mycobacterium bovis BCG in the lungs of infected mice. The two BPD compounds displayed comparable efficacy to rifampicin (RIF) against non-replicating Mtb (NR-Mtb). Importantly, BPD-6 and BPD-9 inhibited the growth of multiple MDR Mtb clinical isolates. Generation of BPD-9-resistant mutants identified the involvement of the Mmr efflux pump as an indirect resistance mechanism. The unique specificity of BPDs to Mycobacterium spp. and their efficacy against MDR Mtb isolates suggest a potential novel mechanism of action. The discovery of BPDs provides novel chemical scaffolds for anti-TB drug discovery.IMPORTANCEThe emergence of drug-resistant tuberculosis (TB) is a serious global health threat. There remains an urgent need to discover new antibiotics with unique mechanisms of action that are effective against drug-resistant Mycobacterium tuberculosis (Mtb). This study shows that novel semi-synthetic compounds can be derived from natural compounds to produce potent activity against Mtb. Importantly, the identified compounds have narrow spectrum activity against Mycobacterium species, including clinical multidrug-resistant (MDR) strains, are effective in infected macrophages and against non-replicating Mtb (NR-Mtb), and show anti-mycobacterial activity in mice. These new compounds provide promising chemical scaffolds to develop potent anti-Mtb drugs of the future.

4.
Proc Natl Acad Sci U S A ; 121(40): e2406294121, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39312670

RESUMO

In the lower respiratory tract, the alveolar spaces are divided from the bloodstream and the external environment by only a few microns of interstitial tissue. Alveolar macrophages (AMs) defend this delicate mucosal surface from invading infections by regularly patrolling the site. AMs have three behavior modalities to achieve this goal: extending cell protrusions to probe and sample surrounding areas, squeezing the whole cell body between alveoli, and patrolling by moving the cell body around each alveolus. In this study, we found Rho GTPase, cell division control protein 42 (CDC42) expression significantly decreased after berry-flavored e-cigarette (e-cig) exposure. This shifted AM behavior from squeezing to probing. Changes in AM behavior led to a reduction in the clearance of inhaled bacteria, Pseudomonas aeruginosa. These findings shed light on pathways involved in AM migration and highlight the harmful impact of e-cig vaping on AM function.


Assuntos
Vapor do Cigarro Eletrônico , Sistemas Eletrônicos de Liberação de Nicotina , Macrófagos Alveolares , Pseudomonas aeruginosa , Macrófagos Alveolares/metabolismo , Animais , Pseudomonas aeruginosa/fisiologia , Vapor do Cigarro Eletrônico/efeitos adversos , Vaping/efeitos adversos , Proteína cdc42 de Ligação ao GTP/metabolismo , Camundongos , Masculino , Camundongos Endogâmicos C57BL
5.
bioRxiv ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39314496

RESUMO

Gene therapy with Adeno-Associated Viral (AAV) vectors requires knowledge of their tropism within the body. Here we analyze the tropism of ten naturally occurring AAV serotypes (AAV3B, AAV4, AAV5, AAV6, AAV7, AAV8, AAV9, AAVrh8, AAVrh10 and AAVrh74) following systemic delivery into male and female mice. A transgene expressing ZsGreen and Cre recombinase was used to identify transduction in a cell-dependent manner based on fluorescence. Cre-driven activation of tdTomato fluorescence offered superior sensitivity for transduced cells. All serotypes except AAV3B and AAV4 had high liver tropism. Fluorescence activation revealed transduction of unexpected tissues, including adrenals, testes and ovaries. Rare transduced cells within tissues were also readily visualized. Biodistribution of AAV genomes correlated with fluorescence, except in immune tissues. AAV4 was found to have a pan-endothelial tropism while also targeting pancreatic beta cells. This public resource enables selection of the best AAV serotypes for basic science and preclinical applications in mice.

6.
Sci Rep ; 14(1): 21663, 2024 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289429

RESUMO

Knowledge on the occurrence and behaviour of baleen whales around sub-Antarctic regions is limited, and usually based on short, seasonal sighting research from shore or research vessels and whaling records, neither of which provide accurate and comprehensive year-round perspectives of these animals' ecology. We investigated the seasonal acoustic occurrence and diel vocalizing pattern of baleen whales around the sub-Antarctic Prince Edward Islands (PEIs) using passive acoustic monitoring data from mid-2021 to mid-2023, detecting six distinct baleen whale songs from Antarctic blue whales, Madagascan pygmy blue whales, fin whales, Antarctic minke whales, humpback whales, and sei whales. Antarctic blue and fin whales were detected year-round whereas the other species' songs were detected seasonally, including a new Antarctic minke whale bio-duck song sub-type described here for the first time. Antarctic minke and sei whales were more vocally active at night-time whereas the other species had no clear diel vocalizing patterns. Random forest models identified month and/or sea surface temperature as the most important predictors of all baleen whale acoustic occurrence. These novel results highlight the PEIs as a useful habitat for baleen whales given the number of species that inhabit or transit through this region.


Assuntos
Acústica , Estações do Ano , Vocalização Animal , Baleias , Animais , Vocalização Animal/fisiologia , Regiões Antárticas , Baleias/fisiologia , Ilhas , Ecossistema
7.
Personal Disord ; 15(5): 293-303, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39235914

RESUMO

Youth with personality pathology are at a greater risk of developing broader psychopathology and experiencing poorer life outcomes in general. Therefore, detecting personality problems, specifically features of borderline personality disorder (BPD), provides opportunities for early intervention. In this study, we investigated the incremental value of Criteria A and B of the alternative model for personality disorders (AMPD) compared to a BPD symptom count based on the Diagnostic and Statistical Manual of Mental Disorders, fifth edition Section II personality disorder model in broader psychopathology (i.e., internalizing and externalizing symptoms) and age-adequate psychosocial functioning (i.e., attainment of developmental milestones). In a clinical sample of 246 young people (Mage = 19.22, SD = 2.76, 81.7% female), separate path analyses showed that a BPD symptom count, Criterion A, and Criterion B were all relatively strongly related to the outcome measures. In a combined path model, the AMPD and especially Criterion B explained additional variance in internalizing and externalizing pathology and age-adequate psychosocial functioning. The current results underscore the value of the AMPD for the early detection of negative psychopathological and psychosocial outcomes commonly associated with BPD. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Transtorno da Personalidade Borderline , Modelos Psicológicos , Funcionamento Psicossocial , Humanos , Feminino , Masculino , Adolescente , Adulto Jovem , Adulto , Transtornos da Personalidade
8.
Am J Physiol Heart Circ Physiol ; 327(4): H1086-H1097, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39212772

RESUMO

Coronary vasomotor dysfunction, an important underlying cause of angina and nonobstructive coronary arteries (ANOCA), encompassing coronary vasospasm, coronary endothelial dysfunction, and/or coronary microvascular dysfunction, is clinically assessed by invasive coronary function testing (ICFT). As ICFT imposes a high burden on patients and carries risks, developing noninvasive alternatives is important. We evaluated whether coronary vasomotor dysfunction is a component of systemic microvascular endothelial and smooth muscle dysfunction and can be detected using laser speckle contrast analysis (LASCA). Forty-three consecutive patients with ANOCA underwent ICFT, with intracoronary acetylcholine, adenosine, and flow measurements, to assess coronary vasomotor dysfunction. Cutaneous microvascular function was assessed using LASCA in the forearm, combined with vasodilators acetylcholine, sodium nitroprusside, and insulin and using EndoPAT, by measuring the reactive hyperemia index (RHI). Of the 43 included patients with ANOCA (79% women, 59 ± 9 yr old), 38 patients had coronary vasomotor dysfunction, including 28 with coronary vasospasm, 26 with coronary endothelial dysfunction, and 18 with coronary microvascular dysfunction, with overlapping endotypes. Patients with and without coronary vasomotor dysfunction had similar peripheral flow responses to acetylcholine, insulin, and RHI. In contrast, coronary vasomotor dysfunction was associated with lower peripheral flow responses to sodium nitroprusside (P < 0.001). An absolute flow response to sodium nitroprusside of 83.95 APU resulted in 86.1% sensitivity and 80.0% specificity for coronary vasomotor dysfunction (area under the ROC curve, 0.883; P = 0.006). In conclusion, this study provides evidence of systemic vascular smooth muscle dysfunction in patients with ANOCA with coronary vasomotor dysfunction and the diagnostic value of peripheral microvascular function testing as a noninvasive tool for detecting coronary vasomotor dysfunction.NEW & NOTEWORTHY This study provides proof of concept that assessment of the peripheral vasculature, particularly vascular smooth muscle cells measured using the LASCA technology holds potential as a noninvasive tool for detecting coronary vasomotor dysfunction. This finding highlights the potential of the LASCA technology in, for example, medication studies for coronary vasomotor dysfunction, especially when investigating whether medication improves vascular function, as repeated peripheral measurements are less invasive than invasive coronary function testing, the current gold standard.


Assuntos
Angina Pectoris , Circulação Coronária , Vasos Coronários , Microcirculação , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Vasos Coronários/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Angina Pectoris/fisiopatologia , Angina Pectoris/diagnóstico , Vasodilatadores/farmacologia , Vasoespasmo Coronário/fisiopatologia , Velocidade do Fluxo Sanguíneo , Endotélio Vascular/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Acetilcolina/farmacologia , Vasodilatação/efeitos dos fármacos , Doença da Artéria Coronariana/fisiopatologia
9.
Front Physiol ; 15: 1399037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39092426

RESUMO

Introduction: The mechanisms leading to the conversion of atrial fibrillation (AF) to sinus rhythm are poorly understood. This study describes the dynamic behavior of electrophysiological parameters and conduction patterns leading to spontaneous and pharmacological AF termination. Methods: Five independent groups of goats were investigated: (1) spontaneous termination of AF, and drug-induced terminations of AF by various potassium channel inhibitors: (2) AP14145, (3) PA-6, (4) XAF-1407, and (5) vernakalant. Bi-atrial contact mapping was performed during an open chest surgery and intervals with continuous and discrete atrial activity were determined. AF cycle length (AFCL), conduction velocity and path length were calculated for each interval, and the final conduction pattern preceding AF termination was evaluated. Results: AF termination was preceded by a sudden episode of discrete activity both in the presence and absence of an antiarrhythmic drug. This episode was accompanied by substantial increases in AFCL and conduction velocity, resulting in prolongation of path length. In 77% ± 4% of all terminations the conduction pattern preceding AF termination involved medial to lateral conduction along Bachmann's bundle into both atria, followed by anterior to posterior conduction. This finding suggests conduction block in the interatrial septum and/or pulmonary vein area as final step of AF termination. Conclusion: AF termination is preceded by an increased organization of fibrillatory conduction. The termination itself is a sudden process with a critical role for the interplay between spatiotemporal organization and anatomical structure.

10.
Eur Heart J Case Rep ; 8(8): ytae386, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39161720

RESUMO

Background: According to the Coronary Vasomotor Disorders International Study (COVADIS) group, the ECG criteria supporting the diagnosis of vasospastic angina (VSA) in spontaneous episodes or induced during intracoronary spasm testing are similar. However, it remains elusive whether acetylcholine-induced ECG changes during epicardial spasms reflect ECG changes that occur during the height of a spontaneous episode. Case summary: We present four patients diagnosed with VSA during intracoronary spasm testing, of whom the ECG characteristics during spasm testing and a spontaneous angina episode are described. All patients have >90% coronary epicardial vasoconstriction in one or more vessels during acetylcholine provocation. ECGs at the height of a spontaneous episode and during acetylcholine-induced coronary spasm are found to be different in three out of four patients. Discussion: In patients with VSA, the ECG at the height of a spontaneous episode and during acetylcholine-induced coronary artery spasm may differ substantially. In patients with symptoms suspicious of VSA, every effort should be undertaken to obtain ECGs during the height of a spontaneous episode of angina pectoris and there should be a low threshold to perform intracoronary function testing.

11.
J Infect Dis ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189818

RESUMO

BACKGROUND: Mycobacterium abscessus complex (MABC), an opportunistic nontuberculous mycobacteria (NTM), can lead to poor clinical outcomes in pulmonary infections. Conflicting data exist on person-to-person transmission of MABC within and across healthcare facilities. To investigate further, a comprehensive retrospective study across five healthcare institutions on the Island of Montréal was undertaken. METHODS: We analyzed the genomes of 221 MABC isolates obtained from 115 individuals (2010-2018) to identify possible links. Genetic similarity, defined as ≤25 single-nucleotide polymorphisms (SNPs), was investigated through a blinded epidemiological inquiry. RESULTS: Bioinformatics analyses identified 28 sequence types (STs), including globally observed dominant circulating clones (DCCs). Further analysis revealed 210 isolate pairs within the SNP threshold. Among these pairs, there was one possible lab contamination where isolates from different patients processed in the same lab differed by only 2 SNPs. There were 37 isolate pairs from patients who had provided specimens from the same hospital; however, epidemiological analysis found no evidence of healthcare-associated person-to-person transmission between these patients. Additionally, pan-genome analysis showed higher discriminatory power than core genome analysis for examining genomic similarity. CONCLUSIONS: Genomics alone is insufficient to establish MABC transmission, particularly considering the genetic similarity and wide distribution of DCCs, although pan-genome analysis has the potential to add further insight. Our findings indicate that MABC infections in Montréal are unlikely attributable to healthcare-associated person-to-person transmission.

12.
Vet Rec ; 195(4): e4533, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39148262

RESUMO

BACKGROUND: The bluetongue virus serotype 3 (BTV-3) outbreak in the Netherlands in 2023 caused severe clinical signs in ruminants. The clinical and pathological signs in ruminants and their spread during the outbreak in 2023 are described. METHODS: Data from the Dutch monitoring and surveillance system were available to describe clinical signs and pathological findings related to BTV-3 in sheep, cattle and goats. During the outbreak, 13 farms (five sheep, five cattle and three dairy goats) were closely monitored. RESULTS: In 2023, BTV-3 infections were confirmed by real-time polymerase chain reaction in sheep flocks (n = 1807), cattle herds (n = 1864), goat herds (n = 62), alpaca and/or llama herds (n = 15) and one dog. Sheep exhibited the most severe clinical signs and had the highest mortality. In other animal species, a large variation in both occurrence and severity of clinical signs was observed. LIMITATION: Only 13 farms were closely monitored. CONCLUSIONS: The clinical signs observed in affected animals during the 2023 BTV-3 outbreak seem to be more severe than those observed during the BTV-8 outbreak between 2006 and 2008. It seems likely that BTV-3 will overwinter, similar to BTV-8. Therefore, the availability of an effective and safe vaccine is crucial to limit the future impact of BTV-3.


Assuntos
Vírus Bluetongue , Bluetongue , Surtos de Doenças , Cabras , Sorogrupo , Animais , Vírus Bluetongue/isolamento & purificação , Bluetongue/epidemiologia , Bluetongue/patologia , Bluetongue/virologia , Países Baixos/epidemiologia , Ovinos , Surtos de Doenças/veterinária , Bovinos , Estudos Soroepidemiológicos , Ruminantes/virologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/virologia , Doenças das Cabras/patologia , Feminino , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , Doenças dos Bovinos/patologia
13.
Nat Commun ; 15(1): 7076, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152113

RESUMO

During the repair of interstrand crosslinks (ICLs) a DNA double-strand break (DSB) is generated. The Fanconi anemia (FA) core complex, which is recruited to ICLs, promotes high-fidelity repair of this DSB by homologous recombination (HR). However, whether the FA core complex also promotes HR at ICL-independent DSBs, for example induced by ionizing irradiation or nucleases, remains controversial. Here, we identified the FA core complex members FANCL and Ube2T as HR-promoting factors in a CRISPR/Cas9-based screen. Using isogenic cell line models, we further demonstrated an HR-promoting function of FANCL and Ube2T, and of their ubiquitination substrate FANCD2. We show that FANCL and Ube2T localize at DSBs in a FANCM-dependent manner, and are required for the DSB accumulation of FANCD2. Mechanistically, we demonstrate that FANCL ubiquitin ligase activity is required for the accumulation of CtIP at DSBs, thereby promoting end resection and Rad51 loading. Together, these data demonstrate a dual genome maintenance function of the FA core complex and FANCD2 in promoting repair of both ICLs and DSBs.


Assuntos
Quebras de DNA de Cadeia Dupla , Proteína do Grupo de Complementação D2 da Anemia de Fanconi , Proteína do Grupo de Complementação L da Anemia de Fanconi , Recombinação Homóloga , Enzimas de Conjugação de Ubiquitina , Humanos , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação L da Anemia de Fanconi/metabolismo , Proteína do Grupo de Complementação L da Anemia de Fanconi/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Sistemas CRISPR-Cas , Ubiquitinação , Anemia de Fanconi/genética , Anemia de Fanconi/metabolismo , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/genética , Células HEK293 , Reparo de DNA por Recombinação , Reparo do DNA , Reparo do DNA por Junção de Extremidades , DNA Helicases
14.
Eur Heart J Case Rep ; 8(8): ytae415, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39211515

RESUMO

Background: Approximately 25% of the general population has a patent foramen ovale (PFO) that remains asymptomatic in the vast majority. Right-to-left shunt (RLS)-mediated hypoxaemia is a rare associated condition of PFO. Case summary: This report describes a case of percutaneous PFO closure for hypoxaemia in a 73-year-old patient showing immediate clinical benefit. She experienced progressive dyspnoea on exertion requiring oxygen therapy. SaO2 was 87% at rest without oxygen therapy, which increased to 98% after percutaneous PFO closure. Discussion: Most PFOs remain clinically insignificant but RLS-mediated hypoxaemia is a rare phenomenon that can occur even at advanced age. Percutaneous PFO closure is a safe and effective therapy option that provides immediate improvement of hypoxaemia.

15.
Bioengineering (Basel) ; 11(8)2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39199765

RESUMO

BACKGROUND: The purpose of this study was to establish a standardized structured workflow to compare findings from high-resolution, optimized reconstructions from post-mortem computed tomography (pmCT) with autopsy results in the detection of fractures of the laryngohyoid complex in strangulation victims. METHOD: Forty-two strangulation cases were selected, and pmCT scans of the laryngohyoid complex were obtained. Both pmCT scans and autopsy reports were analyzed using a structured template and compared using Cohen's kappa coefficient (κ) and the McNemar test. The study also compared the prevalence of ossa sesamoidea and non-fusion of the major and minor horns of the hyoid bone between both diagnostic methods. RESULTS: The detection of fractures showed a very good correlation between autopsy and pmCT results (κ = 0.905), with the McNemar test showing no statistically significant difference between the two methods. PmCT identified 28 sesamoid bones, 45 non-fusions of the major horns, and 47 non-fusions of the minor horns of the hyoid bone, compared to four, six, and zero, respectively, identified by autopsy (p < 0.0001). CONCLUSIONS: Autopsy and pmCT findings correlate well and can be used in a complementary manner. PmCT is superior to autopsy in identifying dislocations and detecting anatomical variations in the laryngohyoid complex, which can lead to misinterpretations during autopsy. Therefore, we do not advocate replacing autopsy with pmCT but propose using a structured workflow, including our standardized reporting template, for evaluating lesions in the laryngohyoid complex.

16.
ACS Appl Nano Mater ; 7(16): 18786-18800, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39206351

RESUMO

The integration of high-κ dielectrics on MoS2 field-effect transistors (FETs) is essential for the realization of MoS2 in ultrascaled nanoelectronic devices and circuits. Most studies covering this topic are based on exfoliated MoS2 flakes or chemical vapor deposition (CVD) grown MoS2 films, whereas other techniques, such as atomic layer deposition (ALD), are also gaining attention for the growth of MoS2 in recent years. In this work, we grow large-area MoS2 by means of plasma-enhanced (PE-)ALD and evaluate the influence of high-κ dielectrics on the properties of ALD-based MoS2 FETs through electrical characterization combined with surface-chemical and high-resolution scanning transmission electron microscopy (HR-STEM) analyses. We grow HfO x , AlO x , or both by means of PE-ALD or thermal ALD on our fabricated devices and show that, in addition to the dielectric constant, three other major parameters related to the processing of the dielectrics can simultaneously affect the MoS2 FET electrical characteristics and govern its doping. These parameters are the stoichiometry of the dielectric, its carbon impurity content, and the degree to which the MoS2 surface oxidizes upon the dielectric growth. When grown at 100 °C, our HfO x films are oxygen-vacant whereas our AlO x films are oxygen-rich. In addition, carbon impurities are incorporated into the dielectrics at low deposition temperatures, being one of the likely causes of the MoS2 FET overall n-type performance in all of the studied cases. Our investigations also reveal that PE-ALD of HfO x or AlO x oxidizes the MoS2 surface, whereas thermal ALD AlO x leaves MoS2 almost intact. In this respect, if thermal ALD AlO x of proper thickness is grown between MoS2 and HfO x , it can reduce the degree to which the MoS2 surface oxidizes by HfO x and meanwhile improve the total dielectric constant, altogether leading to the most optimal electrical performance in ALD-based MoS2 FETs.

17.
Heart ; 110(19): 1172-1179, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39122559

RESUMO

BACKGROUND: Young patients suffering from cryptogenic stroke alongside a patent foramen ovale (PFO) are often considered for percutaneous device closure to reduce the risk of stroke recurrence. Residual right-to-left shunt after device closure may persist in approximately a quarter of the patients at 6 months, and some may close at a later time point. This study aimed to assess the prevalence and persistence of residual right-to-left shunt after percutaneous PFO closure. METHODS: Consecutive patients undergoing transoesophageal echocardiography-guided PFO closure for cryptogenic stroke between 2006 and 2021, with echocardiographic follow-up including contrast bubble study and Valsalva manoeuvre, were enrolled. Follow-up transthoracic echocardiography was performed at 6 months and repeated at 12 months in case of residual right-to-left shunt. Primary outcomes included the prevalence and grade of residual right-to-left shunt at 6 and 12 months after percutaneous PFO closure. RESULTS: 227 patients were included with a mean age of 43±11 years and 50.2% were women. At 6-month follow-up, 72.7% had no residual right-to-left shunt, 12.3% small residual right-to-left shunt, 6.6% moderate residual right-to-left shunt and 8.4% large residual right-to-left shunt. At 12-month follow-up, the presence of residual right-to-left shunt in all patients was 12.3%, of whom 6.6% had small residual right-to-left shunt, 2.6% had moderate residual right-to-left shunt and 3.1% had large residual right-to-left shunt. CONCLUSIONS: Residual right-to-left shunts are common at 6 months after percutaneous closure of PFO. However, the majority are small and two-thirds of residual right-to-left shunts achieve complete closure between 6 and 12 months.


Assuntos
Cateterismo Cardíaco , Ecocardiografia Transesofagiana , Forame Oval Patente , Dispositivo para Oclusão Septal , Humanos , Forame Oval Patente/complicações , Forame Oval Patente/diagnóstico por imagem , Forame Oval Patente/cirurgia , Feminino , Masculino , Ecocardiografia Transesofagiana/métodos , Adulto , Cateterismo Cardíaco/métodos , Fatores de Tempo , Pessoa de Meia-Idade , Resultado do Tratamento , Seguimentos , AVC Isquêmico/etiologia , AVC Isquêmico/prevenção & controle , AVC Isquêmico/epidemiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle
18.
Nanotechnology ; 35(41)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38991513

RESUMO

Among the experimental realization of fault-tolerant topological circuits are interconnecting nanowires with minimal disorder. Out-of-plane indium antimonide (InSb) nanowire networks formed by merging are potential candidates. Yet, their growth requires a foreign material stem usually made of InP-InAs. This stem imposes limitations, which include restricting the size of the nanowire network, inducing disorder through grain boundaries and impurity incorporation. Here, we omit the stem allowing for the growth of stemless InSb nanowire networks on an InP substrate. To enable the growth without the stem, we show that a preconditioning step using arsine (AsH3) is required before InSb growth. High-yield of stemless nanowire growth is achieved by patterning the substrate with a selective-area mask with nanohole cavities, containing restricted gold droplets from which nanowires originate. Interestingly, these nanowires are bent, posing challenges for the synthesis of interconnecting nanowire networks due to merging failure. We attribute this bending to the non-homogeneous incorporation of arsenic impurities in the InSb nanowires and the interposed lattice-mismatch. By tuning the growth parameters, we can mitigate the bending, yielding large and single crystalline InSb nanowire networks and nanoflakes. The improved size and crystal quality of these nanostructures broaden the potential of this technique for fabricating advanced quantum devices.

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