Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Inorg Chem ; 63(4): 1997-2004, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38207101

RESUMO

The reactivity of the base-free bromosilylene dtbpCbzSiBr (dtbpCbz = 1,8-bis(3,5-di-tert-butylphenyl)-3,6-di-tert-butylcarbazolyl) toward carbodiimides and azides was studied in order to generate base-stabilized and base-free silaimidoyl bromides, respectively. The steric bulk of carbodiimides and azides allows control over the reactivity. While with small substituents such as tert-butyl or adamantyl, the reactions cannot be stopped at the Si═N stage, with large substituents, they lead to C-H activation in the product. The Dipp substituent (Dipp = 2,6-diisopropylphenyl) allowed the isolation of the silaimidoyl bromide dtbpCbzSi(Br)NDipp and its CNDipp-coordinated analogue. The reactivity of the Si═N double bond species was studied with respect to cycloaddition and donor exchange reactions.

2.
Urol Int ; : 1-7, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626728

RESUMO

INTRODUCTION: The aim of this study was to assess the feasibility of sparing routine antibiotic prophylaxis in patients without preoperative urinary tract infection undergoing ureterorenoscopy (URS) for stone removal. METHODS: A retrospective, monocentric study was conducted to evaluate the outcome of a modified perioperative antibiotic management strategy according to the principles of antibiotic stewardship. Patients with preoperative unremarkable urine culture received no antibiotic prophylaxis for URS stone removal (NoPAP). The NoPAP group was compared to a historic URS cohort, when antibiotic prophylaxis (PAP) was standard of care. Analysis focused on postoperative complications. RESULTS: Postoperative fever occurred in 1% of the NoPAP and 2% of the PAP patients (p = 0.589). Clavien 1-3 complications did not differ between groups with 9% in the NoPAP and 6.2% in the PAP (p = 0.159). No Clavien 4-5 complications were seen. We identified a residual stone (p = 0.033) and an ASA score 3-4 (p = 0.004) as significant risk factors for postoperative fever. By sparing routine antibiotic prophylaxis, the overall antibiotic usage was reduced from 100% (PAP) to 8.3% (NoPAP). CONCLUSION: Sparing a routine antibiotic prophylaxis during URS for stone removal seems feasible in patients with unremarkable preoperative urine culture for most of the patients. A prospective validation is warranted.

3.
Angew Chem Int Ed Engl ; 63(28): e202405319, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38656624

RESUMO

The general synthesis of heteroleptic acyclic silylenes with a bulky carbazolyl substituent (dtbpCbz) is detailed and a series of compounds with a chalcogenide substituent of the type [(dtbpCbz)SiE16R] (E16R=OtBu, SEt, SePh, TePh) is reported. With the bulky carbazolyl substituent present, the chalcogenide moiety can be very small, as is shown by incorporating groups as small as ethyl, phenyl or tert-butyl. For the first time, the electronic properties of the silylene can be tuned along a complete series of chalcogenide substituents. The effects are clearly visible in the NMR and UV/Vis spectra, and were rationalised by DFT computations. The reactivity of the heaviest chalcogenide-substituted silylenes was probed by reactions with trimethylphosphine selenide and the terphenyl azide TerN3 (Ter=2,6-dimesitylphenyl).

4.
Chemistry ; 29(60): e202302311, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37489573

RESUMO

Silacycles are ubiquitous building blocks. Small silacycles can typically be expanded catalytically. A silirane, silirene and phosphasilirene as well as a siletane and a silolene were prepared starting from the base-free bromosilylene [(dtbp Cbz)SiBr] (dtbp Cbz=1,8-bis(3,5-ditertbutylphenyl)-3,6-ditertbutylcarbazolyl). As these heterocycles were derived from a dicoordinated silylene, they are susceptible to reactions with an external base. The three-membered silacycles readily undergo non-catalysed ring expansion reactions with isonitriles yielding the related four-membered silacycles. Surprisingly, the ring-expanded derivatives of the silirane undergo up to two further isomerisation reactions, first by enamine formation and then by another ring expansion. DFT computations were utilised to gauge the scope of this reactivity pattern. Three-membered silacycles should essentially universally undergo a ring expansion with isonitriles, while for four-membered silacycles, only very few instances are predicted to accommodate more challenging kinetic requirements of this ring expansion. Larger silacycles lack the ring strain energy required for this ring expansion reaction and are not expected to be expanded.

5.
J Cardiovasc Magn Reson ; 25(1): 47, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37574535

RESUMO

BACKGROUND: Parametric mapping sequences in cardiovascular magnetic resonance (CMR) allow for non-invasive myocardial tissue characterization. However quantitative myocardial mapping is still limited by the need for local reference values. Confounders, such as field strength, vendors and sequences, make intersite comparisons challenging. This exploratory study aims to assess whether multi-site studies that control confounding factors provide first insights whether parametric mapping values are within pre-defined tolerance ranges across scanners and sites. METHODS: A cohort of 20 healthy travelling volunteers was prospectively scanned at three sites with a 3 T scanner from the same vendor using the same scanning protocol and acquisition scheme. A Modified Look-Locker inversion recovery sequence (MOLLI) for T1 and a fast low-angle shot sequence (FLASH) for T2 were used. At one site a scan-rescan was performed to assess the intra-scanner reproducibility. All acquired T1- and T2-mappings were analyzed in a core laboratory using the same post-processing approach and software. RESULTS: After exclusion of one volunteer due to an accidentally diagnosed cardiac disease, T1- and T2-maps of 19 volunteers showed no significant differences between the 3 T sites (mean ± SD [95% confidence interval] for global T1 in ms: site I: 1207 ± 32 [1192-1222]; site II: 1207 ± 40 [1184-1225]; site III: 1219 ± 26 [1207-1232]; p = 0.067; for global T2 in ms: site I: 40 ± 2 [39-41]; site II: 40 ± 1 [39-41]; site III 39 ± 2 [39-41]; p = 0.543). CONCLUSION: Parametric mapping results displayed initial hints at a sufficient similarity between sites when confounders, such as field strength, vendor diversity, acquisition schemes and post-processing analysis are harmonized. This finding needs to be confirmed in a powered clinical trial. Trial registration ISRCTN14627679 (retrospectively registered).


Assuntos
Imageamento por Ressonância Magnética , Voluntários , Humanos , Berlim , Reprodutibilidade dos Testes , Valor Preditivo dos Testes , Voluntários Saudáveis , Espectroscopia de Ressonância Magnética
6.
Popul Stud (Camb) ; 76(2): 169-189, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35576966

RESUMO

Fertility preferences have long played a key role in models of fertility differentials and change. We examine the stability of preferences over time using rich panel data on Kenyan women's fertility desires, expectations, actual fertility, and recall of desires in three waves over a nine-year period, when respondents were in their 20s. We find that although desired fertility is quite unstable, most women perceive their desires to be stable. Under hypothetical future scenarios, few expect their desired fertility to increase over time but, in fact, such increases in fertility desires are common. Moreover, when asked to recall past desires, most respondents report previously wanting exactly as many children as they desire today. These patterns of bias are consistent with the emerging view that fertility desires are contextual, emotionally laden, and structured by identity.


Assuntos
Ilusões , Criança , Feminino , Fertilidade , Humanos , Quênia
7.
Clin Oral Investig ; 25(11): 6119-6126, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33813638

RESUMO

OBJECTIVES: Nd:YAG and Er:YAG lasers have been previously used as an adjunct in periodontal therapy. The aim of this single-blinded randomized controlled clinical trial was to evaluate the efficacy of a combined application of Nd:YAG and Er:YAG laser irradiation in periodontal treatment. MATERIALS AND METHODS: Twenty-two patients with at least one site of ≥ 6 mm periodontal probing depth (PPD) after mechanical debridement with curettes and sonic instruments at periodontal reevaluation were included in the study. Patients were randomly allocated at a 1:1 ratio to either a combined Nd:YAG/Er:YAG laser therapy (test group) or a "turned off" laser therapy (control group). The Nd:YAG laser was used for periodontal pocket deepithelialization and to stabilize the resulting blood clot. The Er:YAG laser was primarily used for root surface modification. PPD (mm), clinical attachment level (CAL, mm), and bleeding on probing (BOP, +/-) at the site of laser treatment were evaluated at baseline and 2 months after treatment. RESULTS: The mean improvements from baseline to 2-month follow-up for PPD were significantly better in the laser group (2.05 ± 0.82 mm) compared to the control group (0.64 ± 0.90 mm; p = 0.001). Likewise, the gain in CAL was significantly better in the laser group (1.50 ± 1.10 mm) than in the control group (0.55 ± 1.01mm; p = 0.046). CONCLUSIONS: The combined application of Nd:YAG and Er:YAG laser irradiation as an adjunct to conventional non-surgical therapy showed a significant beneficial effect on periodontal treatment results. CLINICAL RELEVANCE: Combined Nd:YAG and Er:YAG laser irradiation could be a useful procedure additionally to conventional non-surgical periodontal therapy to improve periodontal treatment results. CLINICAL TRIAL REGISTRATION: ISRCTN registry #ISRCTN32132076.


Assuntos
Lasers de Estado Sólido , Doenças Periodontais , Alumínio , Raspagem Dentária , Érbio , Humanos , Lasers de Estado Sólido/uso terapêutico , Neodímio , Ítrio
8.
Nucleic Acids Res ; 46(9): 4456-4468, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29538770

RESUMO

Targeted modulation of gene expression represents a valuable approach to understand the mechanisms governing gene regulation. In a therapeutic context, it can be exploited to selectively modify the aberrant expression of a disease-causing gene or to provide the target cells with a new function. Here, we have established a novel platform for achieving precision epigenome editing using designer epigenome modifiers (DEMs). DEMs combine in a single molecule a DNA binding domain based on highly specific transcription activator-like effectors (TALEs) and several effector domains capable of inducing DNA methylation and locally altering the chromatin structure to silence target gene expression. We designed DEMs to target two human genes, CCR5 and CXCR4, with the aim of epigenetically silencing their expression in primary human T lymphocytes. We observed robust and sustained target gene silencing associated with reduced chromatin accessibility, increased promoter methylation at the target sites and undetectable changes in global gene expression. Our results demonstrate that DEMs can be successfully used to silence target gene expression in primary human cells with remarkably high specificity, paving the way for the establishment of a potential new class of therapeutics.


Assuntos
Inativação Gênica , Divisão Celular/genética , Células Cultivadas , Metilação de DNA , Células HEK293 , Humanos , Receptores CCR5/genética , Receptores CCR5/metabolismo , Linfócitos T/metabolismo , Efetores Semelhantes a Ativadores de Transcrição/química , Fatores de Transcrição/metabolismo
9.
Mol Ther ; 24(3): 636-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26658966

RESUMO

RNA-guided nucleases (RGNs) based on the type II CRISPR-Cas9 system of Streptococcus pyogenes (Sp) have been widely used for genome editing in experimental models. However, the nontrivial level of off-target activity reported in several human cells may hamper clinical translation. RGN specificity depends on both the guide RNA (gRNA) and the protospacer adjacent motif (PAM) recognized by the Cas9 protein. We hypothesized that more stringent PAM requirements reduce the occurrence of off-target mutagenesis. To test this postulation, we generated RGNs based on two Streptococcus thermophilus (St) Cas9 proteins, which recognize longer PAMs, and performed a side-by-side comparison of the three RGN systems targeted to matching sites in two endogenous human loci, PRKDC and CARD11. Our results demonstrate that in samples with comparable on-target cleavage activities, significantly lower off-target mutagenesis was detected using St-based RGNs as compared to the standard Sp-RGNs. Moreover, similarly to SpCas9, the StCas9 proteins accepted truncated gRNAs, suggesting that the specificities of St-based RGNs can be further improved. In conclusion, our results show that Cas9 proteins with longer or more restrictive PAM requirements provide a safe alternative to SpCas9-based RGNs and hence a valuable option for future human gene therapy applications.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Genoma Humano , Streptococcus thermophilus/enzimologia , Streptococcus thermophilus/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Endonucleases/metabolismo , Ativação Enzimática , Vetores Genéticos , Humanos , Ligação Proteica , RNA Guia de Cinetoplastídeos , Especificidade por Substrato
10.
J Am Heart Assoc ; 13(14): e033478, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38958150

RESUMO

BACKGROUND: Results from ATTR-ACT (Safety and Efficacy of Tafamidis in Patients With Transthyretin Cardiomyopathy) indicate that tafamidis prolongs survival and reduces cardiovascular hospitalizations in cardiac transthyretin amyloidosis (ATTR-CA). However, real-world data supporting these findings are scarce. Thus, we sought to characterize the clinical outcome of patients with ATTR-CA treated with tafamidis in a real-world setting and assess the prognostic role of the New York Heart Association (NYHA) classification. METHODS AND RESULTS: We conducted a retrospective observational study, enrolling a consecutive sample of patients with ATTR-CA (wild-type or variant) treated with tafamidis. Clinical outcome was tracked through follow-up visits or phone calls. Primary outcomes were death and major adverse cardiac events (MACE), a composite end point of death and hospitalizations for acute cardiac decompensation, myocardial infarction, severe arrythmias, or stroke. Kaplan-Meier analysis estimated overall and MACE-free survival including NYHA subgroups (NYHA I/II versus NYHA III). One hundred sixty-seven patients with ATTR-CA (94.6% wild-type) were enrolled and followed for a median of 539 [323-869] days. Median overall survival was not reached. Estimated 1-year, 2-year, and 5-year overall survival among the whole cohort was 93.5%, 85.9%, and 70.2%, respectively. Overall survival was higher in the NYHA I/II subgroup (P=0.002). Median MACE-free survival time was 1082 (95% CI, 962-1202) days. MACE-free survival was higher in the NYHA I/II subgroup (P<0.001). With respective hazard ratios of 5.85 (95% CI, 1.48-23.18; P=0.012) and 3.95 (95% CI, 1.99-7.84; P<0.001), NYHA III was an independent predictor of death and MACE. CONCLUSIONS: Treatment of ATTR-CA with tafamidis led to substantial improvements of clinical outcome. NYHA classification at treatment initiation is a reliable tool to provide patients with individualized prognostic information.


Assuntos
Neuropatias Amiloides Familiares , Humanos , Masculino , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/mortalidade , Neuropatias Amiloides Familiares/terapia , Neuropatias Amiloides Familiares/tratamento farmacológico , Feminino , Estudos Retrospectivos , Idoso , Benzoxazóis/uso terapêutico , Pessoa de Meia-Idade , Resultado do Tratamento , Cardiomiopatias/mortalidade , Idoso de 80 Anos ou mais , Fatores de Tempo , Hospitalização/estatística & dados numéricos , Prognóstico
11.
Clin Res Cardiol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466347

RESUMO

BACKGROUND: Aging as a major non-modifiable cardiac risk factor challenges future cardiovascular medicine and economic demands, which requires further assessments addressing physiological age-associated cardiac changes. OBJECTIVES: Using cardiovascular magnetic resonance (CMR), this study aims to characterize sex-specific ventricular adaptations during healthy aging. METHODS: The population included healthy volunteers who underwent CMR at 1.5 or 3 Tesla scanners applying cine-imaging with a short-axis coverage of the left (LV) and right (RV) ventricle. The cohort was divided by sex (female and male) and age (subgroups in years): 1 (19-29), 2 (30-39), 3 (40-49), and 4 (≥50). Cardiac adaptations were quantitatively assessed by CMR indices. RESULTS: After the exclusion of missing or poor-quality CMR datasets or diagnosed disease, 140 of 203 volunteers were part of the final analysis. Women generally had smaller ventricular dimensions and LV mass, but higher biventricular systolic function. There was a significant age-associated decrease in ventricular dimensions as well as a significant increase in LV mass-to-volume ratio (LV-MVR, concentricity) in both sexes (LV-MVR in g/ml: age group 1 vs. 4: females 0.50 vs. 0.57, p=0.016, males 0.56 vs. 0.67, p=0.024). LV stroke volume index decreased significantly with age in both sexes, but stronger for men than for women (in ml/m2: age group 1 vs. 4: females 51.76 vs. 41.94, p<0.001, males 55.31 vs. 40.78, p<0.001). Ventricular proportions (RV-to-LV-volume ratio) were constant between the age groups in both sexes. CONCLUSIONS: In both sexes, healthy aging was associated with an increase in concentricity and a decline in ventricular dimensions. Furthermore, relevant age-related sex differences in systolic LV performance were observed.

12.
Histopathology ; 62(6): 847-59, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23611358

RESUMO

AIMS: To study abnormalities of proteins of the major histocompatibility complex class I in a series of 288 salivary gland carcinomas, and to correlate findings with patients' overall survival (OS). METHODS AND RESULTS: Protein expression of human leukocyte antigen (HLA)-A, heavy chain (HC)-10, ß2 -microglobulin, low molecular weight polypeptides (LMP) 2 and 7, transporters associated with antigen processing (TAP) 1 and 2, calnexin, calreticulin, endoplasmic reticulum (ER) p57 and tapasin was evaluated by immunohistochemistry and semiquantitatively analyzed. As compared with normal salivary gland tissue, HLA-A, LMP7, TAP2 and HLA class I were significantly down-regulated in salivary gland carcinomas, whereas ß2 -microglobulin, calnexin, LMP2, and TAP1 were upregulated. Expression of calreticulin, ERp57 and tapasin was unaltered. In univariate Kaplan-Meier analyses, low expression of LMP7 (P = 0.005) and high expression of ß2 -microglobulin (P = 0.028), HLA-A (P < 0.001), TAP1 (P = 0.01), and tapasin (P < 0.001) were significantly associated with shorter OS. In multivariate analysis incorporating tumour stage, nodal/distant metastasis, and grade, HLA-A (P = 0.014), LMP7 (P = 0.033), and tapasin (P = 0.024), as well as distant metastasis (P = 0.012) and high tumour grade (P < 0.001), remained statistically significant. CONCLUSION: The prognostic influence of up-regulated HLA-A and tapasin and down-regulated LMP7 may provide a rationale for targeting these specific components of the antigen processing and presentation pathway in salivary gland carcinomas.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias das Glândulas Salivares/imunologia , Neoplasias das Glândulas Salivares/patologia , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apresentação de Antígeno , Calnexina/metabolismo , Criança , Cisteína Endopeptidases/metabolismo , Feminino , Antígenos HLA-A/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Complexo de Endopeptidases do Proteassoma/metabolismo , Análise Serial de Tecidos , Adulto Jovem , Microglobulina beta-2/metabolismo
13.
Eur Heart J Case Rep ; 7(1): ytad017, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36733684

RESUMO

Background: Sarcoidosis is a granulomatous multi-organ disease of unknown aetiology. Despite being relatively rare, cardiac sarcoidosis constitutes a very important manifestation of sarcoidosis, as its symptoms regularly precede or occur in isolation of more prevalent ones, and as it is the main driver of mortality in systemic sarcoidosis. Case summary: We present the case of a 37-year-old woman, in which clinically isolated cardiac sarcoidosis revealed widespread systemic sarcoidosis. Apart from constitutional symptoms and strong recurrent dizziness (i.e. near-syncopes), which persisted for multiple years already, our patient initially presented with complex conduction abnormalities, including a right bundle branch block, left anterior hemi-block, and atrioventricular block °1. Following inconclusive endomyocardial biopsies, performed due to detection of focal septal scarring on cardiac magnetic resonance imaging, an 18F-FDG-PET-CT, performed upon admission to our clinic, showed distinct hypermetabolic lesions indicative of active inflammation in various organs and raised suspicion of systemic sarcoidosis. Eventually, histopathological evidence of non-caseating granulomas in affected lymph nodes, extracted by bronchoscopy, confirmed the diagnosis of systemic sarcoidosis after reasonable exclusion of other granulomatous diseases. Immediate initiation of long-term immunosuppressive therapy led to almost complete remission, as monitored by consequential 18F-FDG-PET-CT scans. Discussion: Unexplained complex conduction abnormalities in young patients may be a sign of sarcoidosis, even in isolation of more prevalent symptoms. Correct interpretation and prompt initiation of a structured interdisciplinary diagnostic workup, including 18F-FDG-PET-CT as the imaging modality of choice, are essential to initiate specific treatment and obviate the major risk of mortality resulting from cardiac sarcoidosis.

14.
iScience ; 26(10): 107946, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37854690

RESUMO

Phase Change Materials (PCMs) have demonstrated tremendous potential as a platform for achieving diverse functionalities in active and reconfigurable micro-nanophotonic devices across the electromagnetic spectrum, ranging from terahertz to visible frequencies. This comprehensive roadmap reviews the material and device aspects of PCMs, and their diverse applications in active and reconfigurable micro-nanophotonic devices across the electromagnetic spectrum. It discusses various device configurations and optimization techniques, including deep learning-based metasurface design. The integration of PCMs with Photonic Integrated Circuits and advanced electric-driven PCMs are explored. PCMs hold great promise for multifunctional device development, including applications in non-volatile memory, optical data storage, photonics, energy harvesting, biomedical technology, neuromorphic computing, thermal management, and flexible electronics.

16.
Histopathology ; 61(3): 395-408, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22551398

RESUMO

AIMS: To study the morphological heterogeneity of acinic cell carcinoma (ACC) in correlation with clinicopathological parameters. METHODS AND RESULTS: Forty well-characterized ACCs were classified as solid (n = 20), microcystic (n = 15), papillary-cystic (n = 4) or follicular (n = 1), based on the dominant architectural growth pattern. Fourteen tumours exhibited eosinophilic/clear cell morphology and 18 tumours were rich in zymogen granules (so-called blue dot tumours). High-grade morphology occurred in five tumours. Based on cytokeratin (CK) 7 staining and in analogy to CK7 expression in normal salivary gland epithelia, three distinct histogenetic subtypes were recognized: acinar (CK7-negative; n = 13), ductular (diffuse CK7-positive; n = 11) and mixed ductulo-acinar (10-66% CK7-positive cells; n = 16). Most papillary-cystic tumours displayed ductular differentiation (P = 0.015), whereas blue dot tumours never did (P < 0.001). Analysis of relapse-free survival (RFS) revealed that Stage I tumours had the best prognosis without any relapse in 18 years follow-up (P = 0.06). High-grade tumours were associated with shorter RFS (P = 0.028). Concerning the histogenetic types, monophasic (pure acinar or ductular) tumours were associated with a significantly better RFS than mixed ductulo-acinar tumours (P = 0.008). CONCLUSION: The results underscore the great histological diversity of ACC, and the value of histogenetic subtyping as an additional prognostic factor regarding RFS.


Assuntos
Carcinoma de Células Acinares/metabolismo , Carcinoma de Células Acinares/patologia , Neoplasias das Glândulas Salivares/metabolismo , Neoplasias das Glândulas Salivares/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Carcinoma de Células Acinares/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias das Glândulas Salivares/mortalidade , Adulto Jovem
17.
Nat Commun ; 13(1): 7352, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446781

RESUMO

In glasses, secondary (ß-) relaxations are the predominant source of atomic dynamics. Recently, they have been discovered in covalently bonded glasses, i.e., amorphous phase-change materials (PCMs). However, it is unclear what the mechanism of ß-relaxations is in covalent systems and how they are related to crystallization behaviors of PCMs that are crucial properties for non-volatile memories and neuromorphic applications. Here we show direct evidence that crystallization is strongly linked to ß-relaxations. We find that the ß-relaxation in Ge15Sb85 possesses a high tunability, which enables a manipulation of crystallization kinetics by an order of magnitude. In-situ synchrotron X-ray scattering, dielectric functions, and ab-initio calculations indicate that the weakened ß-relaxation intensity stems from a local reinforcement of Peierls-like distortions, which increases the rigidity of the bonding network and decreases the dynamic heterogeneity. Our findings offer a conceptually new approach to tuning the crystallization of PCMs based on manipulating the ß-relaxations.

18.
Histopathology ; 58(4): 557-70, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21371076

RESUMO

AIMS: To correlate World Health Organization (WHO) grade, patient's outcome and presence of t(11;19) to histological tumour variants in 40 well-characterized mucoepidermoid carcinomas (MECs). METHODS AND RESULTS: MECs were classified as 'classical' based on the presence of equal proportions of the three cell types or the dominance (≥50%) of mucous cells together with at least one other cell type, and as 'variant' if composed of ≥80% of a single non-mucous cell type. Classical MECs were more common (n=23). Variant MECs had predominant squamoid (n=9), eosinophilic (n=5) or clear cell (n=3) morphology. Twenty-seven tumours were WHO grade 1, three grade 2 and ten grade 3. The t(11;19) was detected in 82%, 35% and 0% of classical MEC, variant MEC and non-MEC, respectively. Classical MECs were associated significantly with age ≤60 years (P<0.001), grade 1 (P<0.001) and t(11;19) (P=0.003). Short overall survival was associated significantly with age >60 years (P=0.001) and Union for International Cancer Control (UICC) stage >I (P=0.031), residual tumour (P<0.001), tumour grade >1 (P=0.001) and squamoid variant (P=0.002) in Kaplan-Meier analysis. CONCLUSIONS: The results underscore the great histological diversity of MEC, the reproducibility of the WHO grading criteria and the value of histological subtypes as an additional prognostic factor.


Assuntos
Carcinoma Mucoepidermoide/patologia , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 19/genética , Neoplasias das Glândulas Salivares/patologia , Translocação Genética , Análise de Variância , Carcinoma Mucoepidermoide/genética , Intervalos de Confiança , Diagnóstico Diferencial , Feminino , Alemanha , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Neoplasias das Glândulas Salivares/genética , Glândulas Salivares/patologia , Fatores de Tempo , Translocação Genética/genética
19.
Chem Commun (Camb) ; 57(93): 12532-12535, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34751692

RESUMO

We report details of our attempts to reduce the bulky carbazolyl diiodoalane [R-AlI2]. The reducing agents employed include KC8, Cp*2Co and the Mg(I) compound [(MesBDI)Mg]2. The use of KC8 allowed the spectroscopic observation of the alanediyl [R-Al]. With Cp*2Co as the reducing agent, the alanediyl [R-Al] was obtained as a crystalline material in low yield, but paramagnetic impurities remained. When diiodoalane [R-AlI2] was treated with [(MesBDI)Mg]2, no reduction but a 2 : 1 addition was observed.

20.
Environ Toxicol Chem ; 40(1): 88-99, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33079390

RESUMO

Storm events lead to agricultural and urban runoff, to mobilization of contaminated particulate matter, and to input from combined sewer overflows into rivers. We conducted time-resolved sampling during a storm event at the Ammer River, southwest Germany, which is representative of small river systems in densely populated areas with a temperate climate. Suspended particulate matter (SPM) and water from 2 sampling sites were separately analyzed by a multi-analyte liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for 97 environmentally relevant organic micropollutants and with 2 in vitro bioassays. Oxidative stress response (AREc32) may become activated by various stressors covering a broad range of physicochemical properties and induction of aryl hydrocarbon receptor-chemical-activated luciferase gene expression (AhR-CALUX) by hydrophobic compounds such as dioxins and dioxin-like molecules. Compound numbers, concentrations, their mass fluxes, and associated effect fluxes increased substantially during the storm event. Micropollutants detected in water and on SPM pointed toward inputs from combined sewer overflow (e.g., caffeine, paracetamol), urban runoff (e.g., mecoprop, terbutryn), and agricultural areas (e.g., azoxystrobin, bentazone). Particle-facilitated transport of triphenylphosphate and tris(1-chloro-2-propyl) phosphate accounted for up to 34 and 33% of the total mass flux even though SPM concentrations were <1 g L-1 . Effect fluxes attributed to SPM were similar or higher than in the water phase. The important role of SPM-bound transport emphasizes the need to consider not only concentrations but also mass and effect fluxes for surface water quality assessment and wastewater/stormwater treatment options. Environ Toxicol Chem 2021;40:88-99. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cromatografia Líquida , Monitoramento Ambiental , Chuva , Rios , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Abastecimento de Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA