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2.
Oral Oncol ; 152: 106744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38520756

RESUMO

PURPOSE: In clinical practice the assessment of the "vocal cord-arytenoid unit" (VCAU) mobility is crucial in the staging, prognosis, and choice of treatment of laryngeal squamous cell carcinoma (LSCC). The aim of the present study was to measure repeatability and reliability of clinical assessment of VCAU mobility and radiologic analysis of posterior laryngeal extension. METHODS: In this multi-institutional retrospective study, patients with LSCC-induced impairment of VCAU mobility who received curative treatment were included; pre-treatment endoscopy and contrast-enhanced imaging were collected and evaluated by raters. According to their evaluations, concordance, number of assigned categories, and inter- and intra-rater agreement were calculated. RESULTS: Twenty-two otorhinolaryngologists evaluated 366 videolaryngoscopies (total evaluations: 2170) and 6 radiologists evaluated 237 imaging studies (total evaluations: 477). The concordance of clinical rating was excellent in only 22.7% of cases. Overall, inter- and intra-rater agreement was weak. Supraglottic cancers and transoral endoscopy were associated with the lowest inter-observer reliability values. Radiologic inter-rater agreement was low and did not vary with imaging technique. Intra-rater reliability of radiologic evaluation was optimal. CONCLUSIONS: The current methods to assess VCAU mobility and posterior extension of LSCC are flawed by weak inter-observer agreement and reliability. Radiologic evaluation was characterized by very high intra-rater agreement, but weak inter-observer reliability. The relevance of VCAU mobility assessment in laryngeal oncology should be re-weighted. Patients affected by LSCC requiring imaging should be referred to dedicated radiologists with experience in head and neck oncology.


Assuntos
Neoplasias Laríngeas , Prega Vocal , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Prega Vocal/diagnóstico por imagem , Prega Vocal/fisiopatologia , Adulto , Reprodutibilidade dos Testes , Idoso de 80 Anos ou mais , Laringoscopia/métodos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-37937715

RESUMO

BACKGROUND AND OBJECTIVE: The safety profile of venom immunotherapy (VIT) is a relevant issue and considerable differences in safety and efficacy of VIT have been reported. The primary aim of this study was to evaluate the safety of ACE inhibitors and beta-blockers during VIT, which has already been published. For a second analysis, data concerning premedication and venom preparations in relation to systemic adverse events (AE) during the up-dosing phase and the first year of the maintenance phase were evaluated as well as the outcome of field stings and sting challenges. METHODS: The study was conducted as an open, prospective, observational, multicenter study. In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. RESULTS: Premedication with oral antihistamines was taken by 52.1% of patients during the up-dosing and 19.7% of patients during the maintenance phase. Taking antihistamines had no effect on the frequency of systemic AE (p=0.11) but large local reactions (LLR) were less frequently seen (OR: 0.74; 95% CI: 0.58-0.96; p=0.02). Aqueous preparations were preferentially used for up-dosing (73.0%) and depot preparations for the maintenance phase (64.5%). The type of venom preparation neither had an influence on the frequency of systemic AE nor on the effectiveness of VIT (p=0.26 and p=0.80, respectively), while LLR were less frequently seen when depot preparations were used (p<0.001). CONCLUSION: Pretreatment with oral antihistamines during VIT significantly reduces the frequency of LLR but not systemic AE. All venom preparations used were equally effective and did not differ in the frequency of systemic AE.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37671889
5.
J Neurol ; 270(11): 5475-5482, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37491680

RESUMO

BACKGROUND: Given that the pathogenetic process of ALS begins many years prior to its clinical onset, examining patients' residential histories may offer insights on the disease risk factors. Here, we analyzed the spatial distribution of a large ALS cohort in the 50 years preceding the disease onset. METHODS: Data from the PARALS register were used. A spatial cluster analysis was performed at the time of disease onset and at 1-year intervals up to 50 years prior to that. RESULTS: A total of 1124 patients were included. The analysis revealed a higher-incidence cluster in a large area (435,000 inhabitants) west of Turin. From 9 to 2 years before their onset, 105 cases were expected and 150 were observed, resulting in a relative risk of 1.49 (P = 0.04). We also found a surprising high number of patients pairs (51) and trios (3) who lived in the same dwelling while not being related. Noticeably, these occurrences were not observed in large dwellings as we would have expected. The probability of this occurring in smaller buildings only by chance was very low (P = 0.01 and P = 0.04 for pairs and trios, respectively). CONCLUSIONS: We identified a higher-incidence ALS cluster in the years preceding the disease onset. The cluster area being densely populated, many exposures could have contributed to the high incidence ALS cluster, while we could not find a shared exposure among the dwellings where multiple patients had lived. However, these findings support that exogenous factors are likely involved in the ALS pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/etiologia , Risco , Incidência , Análise por Conglomerados
6.
Acta Neurochir (Wien) ; 165(4): 983-987, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36645489

RESUMO

BACKGROUND: Thoracic pial arteriovenous fistulas (pAVFs) are rare vascular malformations that usually consist of a single dilated pial artery connecting directly to an enlarged draining vein. Multiple shunting point thoracic pAVFs are even rarer entities causing progressive myelopathy. METHOD: We present our surgical technique to identify and exclude multiple shunting point thoracic pAVF with appropriate pre-operative planning. This surgical technique is illustrated by an intraoperative video. CONCLUSION: Double injection pre-operative angiography represents a helpful tool to plan the surgery. Intraoperative exposure with pedicle removal and the use of micro-Doppler improve the identification and the exclusion of a multiple shunting thoracic pAVF.


Assuntos
Fístula Arteriovenosa , Malformações Arteriovenosas Intracranianas , Humanos , Angiografia Cerebral , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/cirurgia , Procedimentos Neurocirúrgicos , Procedimentos Cirúrgicos Vasculares , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/cirurgia
7.
Acta Gastroenterol Belg ; 85(4): 581-858, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36566367

RESUMO

Objective: The role of pre-procedure SARS-CoV2 testing in digestive endoscopy is still debated. AGA guidelines recommend against pre-procedure testing considering low prevalence of SARS- CoV2 infection in the general population and low incidence of infection among endoscopy units Health Care Workers (HCWs). However, no studies have compared pre-procedure testing associated to symptom screening vs. symptom screening alone in reducing the risk of infection for HCWs. Main aim of the present study is to compare the risk of infection for HCWs in different Endoscopy Units adopting different pre-endoscopy screening and operating in two nearby hospital of the same region in Northern Italy in pre-vaccination period. For outpatients in the Endoscopy Unit of Trento (Unit 1) only pre-procedure symptom screening was performed, while in the Endoscopy Unit of Bolzano (Unit 2) pre-procedure symptom screening and negative pre-procedure real-time PCR were requested. Secondary aims were to assess the impact of pre-procedure real-time PCR testing on endoscopic activity and diagnostic delay. Design: Retrospective data collection on a prospectively maintained database was performed, including outpatient endoscopy procedures performed between June 1st 2020 and February 28th 2021 in Unit 1 and Unit 2. Results: No differences in terms of infection rate in HCWs have been identified in Unit 1 and Unit 2 (9.0 vs. 19.3% P=0.2) over a nine-month period. Moreover, in the unit performing pre- procedure real-time PCR before endoscopy a significantly higher reduction in endoscopic activity has been recorded (61.9% vs. 53.4%; P<0.01). In patients with positive real-time PCR, endoscopy was performed with a mean delay of 61.7 days (range 9-294) and 22.5% of them were lost at follow-up and did not undergo any endoscopic procedure in the following 12 months. Conclusions: This study supports the AGA recommendation suggesting that pre-endoscopy real-time PCR is an expensive and time-consuming procedure without proven benefits in an outpatient setting.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2 , Pacientes Ambulatoriais , RNA Viral , Estudos Retrospectivos , Diagnóstico Tardio , Reação em Cadeia da Polimerase em Tempo Real , Endoscopia Gastrointestinal , Pessoal de Saúde
8.
J Dairy Sci ; 105(3): 2228-2241, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34998571

RESUMO

We evaluated the effects of supplemental calcium ammonium nitrate (CAN) fed to dairy cows on dry matter (DM) intake, nutrient digestibility, milk quality, microbial protein synthesis, and ruminal fermentation. Six multiparous Holstein cows at 106 ± 14.8 d in milk, with 551 ± 21.8 kg of body weight were used in a replicated 3 × 3 Latin square design. Experimental period lasted 21 d, with 14 d for an adaptation phase and 7 d for sampling and data collection. Cows were randomly assigned to receive the following treatments: URE, 12 g of urea/kg of DM as a control group; CAN15, 15 g of CAN/kg of DM; and CAN30, 30 g of CAN/kg of DM. Supplemental CAN reduced DM intake (URE 19.0 vs. CAN15 18.9 vs. CAN30 16.5 kg/d). No treatment effects were observed for apparent digestibility of DM, organic matter, crude protein, ether extract, and neutral detergent fiber; however, CAN supplementation linearly increased nonfiber carbohydrate digestibility. Milk yield was not affected by treatments (average = 23.1 kg/d), whereas energy-corrected milk (ECM) and 3.5% fat-corrected milk (FCM) decreased as the levels of CAN increased. Nitrate residue in milk increased linearly (URE 0.30 vs. CAN15 0.33 vs. CAN30 0.38 mg/L); however, treatments did not affect nitrite concentration (average: 0.042 mg/L). Milk fat concentration was decreased (URE 3.39 vs. CAN15 3.35 vs. CAN30 2.94%), and the proportion of saturated fatty acids was suppressed by CAN supplementation. No treatment effects were observed on the reducing power and thiobarbituric acid reactive substances of milk, whereas conjugated dienes increased linearly (URE 47.6 vs. CAN15 52.7 vs. CAN30 63.4 mmol/g of fat) with CAN supplementation. Treatments had no effect on microbial protein synthesis; however, molar proportion of ruminal acetate and acetate-to-propionate ratio increased with CAN supplementation. Based on the results observed, supplementing CAN at 30 g/kg of DM should not be recommended as an optimal dose because it lowered DM intake along with ECM and 3.5% FCM, although no major changes were observed on milk quality and ruminal fermentation.


Assuntos
Leite , Nitratos , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Digestão , Ingestão de Alimentos , Feminino , Fermentação , Lactação , Leite/química , Nitratos/farmacologia , Compostos de Amônio Quaternário , Rúmen/metabolismo
9.
Int J Oral Maxillofac Surg ; 51(6): 724-731, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34535350

RESUMO

Midline and paramedian mandibulotomies both have distinct anatomical and surgical strengths. A retrospective study was performed at Chang Gung Memorial Hospital, Linkou Branch between 2014 and 2019 to investigate how the osteotomy site (midline (n = 221) or paramedian (n = 44)) and type (straight, notched, or stair-stepped) affect postoperative and post-radiotherapy complications in patients undergoing wide excision of tongue cancer with flap reconstruction. Midline mandibulotomies were predominantly of the straight osteotomy type, while paramedian mandibulotomies were mostly notched type (P < 0.001). Comparably low elective tooth extraction rates were found in both approaches (P = 0.556). Paramedian mandibulotomy showed a higher osteoradionecrosis rate (P = 0.026), but there was no significance in the sub-analysis of individual types. Paramedian sites were associated with more early infection (P = 0.036) and plate exposure (P = 0.036) than midline sites with the straight osteotomy type, but complication rates did not differ significantly for the notched and stair-stepped types. Paramedian sites (P = 0.020) and notched types (P = 0.006) were associated with higher odds of osteoradionecrosis in the univariable logistic regression analysis, but only the notched type remained significant in the multivariable analysis (P = 0.048). In conclusion, paramedian sites increased the rate of osteoradionecrosis, and correlation with the osteotomy type resulted in more osteoradionecrosis in notched types and more complications in straight paramedian mandibulotomies.


Assuntos
Osteorradionecrose , Neoplasias da Língua , Humanos , Mandíbula/cirurgia , Osteotomia Mandibular , Osteorradionecrose/cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Neoplasias da Língua/cirurgia
10.
Braz J Med Biol Res ; 54(3): e9571, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33470396

RESUMO

Cancer cell lines are widely used as in vitro models of tumorigenesis, facilitating fundamental discoveries in cancer biology and translational medicine. Currently, there are few options for glioblastoma (GBM) treatment and limited in vitro models with accurate genomic and transcriptomic characterization. Here, a detailed characterization of a new GBM cell line, namely AHOL1, was conducted in order to fully characterize its molecular composition based on its karyotype, copy number alteration (CNA), and transcriptome profiling, followed by the validation of key elements associated with GBM tumorigenesis. Large numbers of CNAs and differentially expressed genes (DEGs) were identified. CNAs were distributed throughout the genome, including gains at Xq11.1-q28, Xp22.33-p11.1, Xq21.1-q21.33, 4p15.1-p14, 8q23.2-q23.3 and losses at Yq11.21-q12, Yp11.31-p11.2, and 15q11.1-q11.2 positions. Nine druggable genes were identified, including HCRTR2, ETV1, PTPRD, PRKX, STS, RPS6KA6, ZFY, USP9Y, and KDM5D. By integrating DEGs and CNAs, we identified 57 overlapping genes enriched in fourteen pathways. Altered expression of several cancer-related candidates found in the DEGs-CNA dataset was confirmed by RT-qPCR. Taken together, this first comprehensive genomic and transcriptomic landscape of AHOL1 provides unique resources for further studies and identifies several druggable targets that may be useful for therapeutics and biologic and molecular investigation of GBM.


Assuntos
Glioblastoma , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Genoma , Genômica , Glioblastoma/genética , Histona Desmetilases , Humanos , Antígenos de Histocompatibilidade Menor , Transcriptoma
11.
Braz. j. med. biol. res ; 54(3): e9571, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153526

RESUMO

Cancer cell lines are widely used as in vitro models of tumorigenesis, facilitating fundamental discoveries in cancer biology and translational medicine. Currently, there are few options for glioblastoma (GBM) treatment and limited in vitro models with accurate genomic and transcriptomic characterization. Here, a detailed characterization of a new GBM cell line, namely AHOL1, was conducted in order to fully characterize its molecular composition based on its karyotype, copy number alteration (CNA), and transcriptome profiling, followed by the validation of key elements associated with GBM tumorigenesis. Large numbers of CNAs and differentially expressed genes (DEGs) were identified. CNAs were distributed throughout the genome, including gains at Xq11.1-q28, Xp22.33-p11.1, Xq21.1-q21.33, 4p15.1-p14, 8q23.2-q23.3 and losses at Yq11.21-q12, Yp11.31-p11.2, and 15q11.1-q11.2 positions. Nine druggable genes were identified, including HCRTR2, ETV1, PTPRD, PRKX, STS, RPS6KA6, ZFY, USP9Y, and KDM5D. By integrating DEGs and CNAs, we identified 57 overlapping genes enriched in fourteen pathways. Altered expression of several cancer-related candidates found in the DEGs-CNA dataset was confirmed by RT-qPCR. Taken together, this first comprehensive genomic and transcriptomic landscape of AHOL1 provides unique resources for further studies and identifies several druggable targets that may be useful for therapeutics and biologic and molecular investigation of GBM.


Assuntos
Humanos , Glioblastoma/genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Menor , Genoma , Genômica , Linhagem Celular Tumoral , Histona Desmetilases , Transcriptoma
12.
Oral Oncol ; 109: 104867, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32593953

RESUMO

INTRODUCTION: Fine-needle aspiration cytology (FNAC) is a basic step in the diagnosis of salivary gland tumors that have a wide variety of histological types. The recent Milan system for reporting salivary gland cytopathology (MSRSGC) can correlate the risk of malignancy with precise cytological features. A revised version was recently proposed to improve the surgical relevance and facilitate uniform management. MATERIAL AND METHODS: A multicenter study retrospectively used the original and revised MSRSGC criteria to classify a series of patients who received surgery after FNAC. RESULTS: We enrolled 503 patients from three tertiary centers. The risk of malignancy for the MSRSGC resulted 19.5% in cat. I, 14.3% in cat. II, 17.6% in cat. III, 3.6% in cat. IVa, 24.6% in cat. IVb, 66.7% in cat. V, and 96.8% in cat. VI. The results from the revised MSRSGC were consistent with the original values. CONCLUSION: The MSRSGC is a promising classification system. In our opinion, the revised version of the MSRSGC supplements FNAC with some crucial clinical information and can better identify the appropriate treatment in each category.

13.
Nat Mater ; 19(8): 874-880, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32424372

RESUMO

Two-dimensional materials with high charge carrier mobility and tunable band gaps have attracted intense research effort for their potential use in nanoelectronics. Two-dimensional π-conjugated polymers constitute a promising subclass because the band structure can be manipulated by varying the molecular building blocks while preserving key features such as Dirac cones and high charge mobility. The major barriers to the application of two-dimensional π-conjugated polymers have been the small domain size and high defect density attained in the syntheses explored so far. Here, we demonstrate the fabrication of mesoscale ordered two-dimensional π-conjugated polymer kagome lattices with semiconducting properties, Dirac cone structures and flat bands on Au(111). This material has been obtained by combining a rigid azatriangulene precursor and a hot dosing approach, which favours molecular diffusion and eliminates voids in the network. These results open opportunities for the synthesis of two-dimensional π-conjugated polymer Dirac cone materials and their integration into devices.

14.
J Endocrinol Invest ; 43(11): 1623-1630, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32319048

RESUMO

INTRODUCTION: Vitamin D is involved in the regulatory mechanisms of ovarian function and is frequently low in PCOS patients. Since obesity and hyperinsulinemic state negatively influenced vitamin D levels, therefore, we evaluated the production of vitamin D at the ovarian level only in lean and normoinsulinemic PCOS subjects. Basal, GnRH analogue-induced ovarian production of 25OH-vitamin D (VitD) and a direct sampling at ovarian vein level were investigated. METHODS: Basal and GnRH analogue-induced hormone levels were evaluated at peripheral level in 45 subjects, aged 18-39 years, and in 22 healthy women with age- and BMI-matched as controls. In 12 PCOS patients, undergoing laparoscopy, a venous sampling at both peripheral and ovarian level was further done. All subjects presented low VitD levels, appropriate to the season and with no difference between PCOS and control subjects. RESULTS: GnRH analogue significantly stimulated plasma LH, FSH, 17-OHP and estradiol secretion (p from < 0.05 to < 0.001 vs basal levels), whereas no effect was observed on both serum AMH and VitD concentrations in all groups. A significant difference (p < 0.006), between peripheral and ovarian veins, was observed in both AMH and estradiol levels in PCOS subjects, while no gradient of VitD was detected. CONCLUSIONS: All patients presented with low VitD levels. The absence of any VitD variation, both at basal and after GnRH analogue administration, or at peripheral-ovarian vein gradient, suggests no pituitary-ovarian axis involvement in VitD production or its direct ovarian production in lean and normoinsulinemic PCOS subjects.


Assuntos
Hidroxicolecalciferóis/metabolismo , Ovário/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adolescente , Adulto , Coleta de Amostras Sanguíneas , Estudos de Casos e Controles , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Ovário/irrigação sanguínea , Ovário/patologia , Síndrome do Ovário Policístico/patologia , Vitamina D/sangue , Adulto Jovem
15.
Eur J Neurol ; 27(8): 1397-1404, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32346913

RESUMO

BACKGROUND AND PURPOSE: The aim was to assess the frequency of plateaus in amyotrophic lateral sclerosis (ALS) progression using a large population-based cohort. METHODS: Data from the Piemonte and Valle d'Aosta ALS register were used. Patients who were diagnosed between 2007 and 2014 were considered. The follow-up period was extended until 31 December 2018. Visits after tracheostomy were excluded. A plateau was defined as a stable Amyotrophic Lateral Sclerosis Functional Rating Scale revised (ALSFRSr) score lasting at least 6, 12 or 18 months. RESULTS: Out of 1214 patients, 200 (16.5%), 93 (7.7%) and 52 (4.3%) showed at least one plateau lasting a minimum of 6, 12 and 18 months, respectively. Plateaus occurred mostly at high ALSFRSr scores and were more frequent during the initial phases of the disease course. Spinal onset [odds ratio (OR) 1.83, 95% confidence interval (CI) 1.16-2.95, P value 0.01) and predominant upper motor neuron phenotype (OR 2.18, 95% CI 1.36-3.48, P value 0.001) conferred a higher risk for the subsequent appearance of plateaus; conversely, older age at diagnosis (OR 0.25, 95% CI 0.11-0.54, P value 0.002 for >75 year age class) reduced this risk. CONCLUSIONS: Plateaus in ALS progression lasting at least 6 months appear in about one out of six patients and could last even 12, 18 months or more in a smaller subgroup of patients. Plateau occurrence should not lead the neurologist to automatically reconsider ALS diagnosis and should be considered for future clinical trial design.


Assuntos
Esclerose Lateral Amiotrófica , Idoso , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/cirurgia , Estudos de Coortes , Progressão da Doença , Humanos , Traqueostomia
16.
Nanoscale ; 11(41): 19468-19476, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31535121

RESUMO

The formation of ordered molecular structures on surfaces is determined by the balance between molecule-molecule and molecule-substrate interactions. Whether the aggregation process is guided by non-covalent forces or on-surface reactions, a deeper understanding of these interactions is pivotal to formulating a priori predictions of the final structural features and the development of bottom-up fabrication protocols. Theoretical models of molecular systems corroborate the information gathered through experimental observations and help explain the thermodynamic factors that underpin on-surface phase transitions. Here, we report a scanning tunneling microscopy investigation of a tribromo-substituted heterotriangulene on the Au(111) surface, which initially forms an extended close-packed ordered structure stabilized by BrBr halogen bonds when deposited at room temperature. X-ray photoelectron spectroscopy reveals that annealing the self-assembled layer induces a fraction of the molecular precursors to partially dehalogenate that in turn leads to the formation of a less stable BrO non-covalent network which coexists with the short oligomers. Density functional theory (DFT) and Monte Carlo (MC) simulations illustrate how dimer moieties act as defects whose steric hindrance prevents the retention of the more stable configuration. A small number of dimers is sufficient to drive the molecular reorganization into a lower cohesive energy phase. Our study shows the importance of a combined DFT - MC approach to understand the evolution of molecular systems on substrates.

17.
Chem Sci ; 10(19): 5167-5175, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31183070

RESUMO

Ullmann coupling of halogenated aromatics is widely used in on-surface synthesis of two-dimensional (2D) polymers and graphene nanoribbons. It stands out among other reactions for regioselectively connecting aromatic monomers into 1D and 2D π-conjugated polymers, whose final structure and properties are determined by the initial building blocks. Thanks to their exceptional electronic properties, thiophene-containing monomers are frequently used for the synthesis of various conjugated materials. On the other hand, their use in on-surface polymerization is hampered by the possibility of ring opening when adsorbed on metal surfaces. In the present work, we mapped the temperature regime for these two competing reactions by investigating the adsorption of a thiophene-based prochiral molecule using scanning tunneling microscopy, X-ray photoelectron spectroscopy and density functional theory calculations. We followed the formation of organometallic (OM) networks, their evolution into covalent structures and the competition between C-C coupling and thiophene ring opening. The effect of surface reactivity was explored by comparing the adsorption on three (111) coinage metal substrates, namely Au, Ag and Cu. While outlining strategies to minimize the ring opening reaction, we found that the surface temperature during deposition is of paramount importance for the preparation of 2D OM networks, greatly enhancing the overall ordering of the product by depositing on hot Ag surface. Notably, the same protocol permits the creation of OM structures on the air-stable Au surface, thereby allowing the synthesis and application of 2D OM networks outside the ultra-high vacuum environment.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31136852

RESUMO

Copper is a metal that participates in several essential reactions in living organisms, and it has been used as an inflammatory inducing agent in zebrafish larvae. In this study, we evaluated the effect P2X7 receptor and/or pannexin channel 1 (PANX-1) blockage in this inflammation model. To perform the experiments, 7 dpf larvae were exposed to 10 µM of copper and treated with 100 µM probenecid, PANX-1 inhibitor, and/or 300 nM A740003, a P2X7R selective antagonist. Larvae survival was assessed up to 24 h after treatments. The evaluation of larvae behavior was evaluated after acute (4 h) and chronic (24 h) exposure. The parameters of locomotor activity measured were: mobile time, average speed, distance and turn angle. We analyzed the gene expression of the P2X7 receptor, PANX1a and PANX1b channels and interleukins IL-10 and IL-1b after 24 h of treatment. Treatments did not decrease larval survival in the time interval studied. Changes in larvae locomotion were observed after the longest time of exposure to copper and the treatment with probenecid was able to reverse part of the effects caused by copper. No significant difference was observed in the oxidative stress assays and probenecid and copper treatment decrease partially PANX1a gene expression groups. The data presented herein shows the relevance of the blockage of P2X7-PANX-1 in copper-induced inflammation.


Assuntos
Conexinas/genética , Cobre/toxicidade , Inflamação/induzido quimicamente , Receptores Purinérgicos P2X7/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Acetamidas/farmacologia , Animais , Conexinas/antagonistas & inibidores , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/mortalidade , Interleucina-10/genética , Interleucina-1beta/genética , Larva/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Masculino , Estresse Oxidativo , Probenecid/farmacologia , Antagonistas do Receptor Purinérgico P2X/toxicidade , Quinolinas/farmacologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/antagonistas & inibidores
19.
Nanoscale ; 11(12): 5422-5428, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30855042

RESUMO

Investigating two-dimensional (2D) self-assembled structures of biological monomers governed by intermolecular interactions is a prerequisite to understand the self-assembly of more complex biomolecular systems. 5,6-Dihydroxyindole carboxylic acid (DHICA) is one of the building blocks of eumelanin - an irregular heteropolymer and the most common form of melanin which has potential applications in organic electronics and bioelectronics. By means of scanning tunneling microscopy, density functional theory and Monte Carlo calculations, we investigate DHICA molecular configurations and interactions underlying the multiple 2D patterns formed on Au(111). While DHICA self-assembled molecular networks (SAMNs) are dominated by the hydrogen bonding of carboxylic acid dimers, a variety of 2D architectures are formed due to the multiple weak interactions of the catechol group. The hydroxyl group also allows for redox reactions, caused by oxidation via O2 exposure, resulting in molecular rearrangement. The susceptibility of the molecules to oxidation is affected by their SAMNs architectures, giving insights on the reactivity of indoles as well as highlighting non-covalent assembly as an approach to guide selective oxidation reactions.

20.
Int J Neurosci ; 129(7): 719-721, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30146930

RESUMO

The association between Amyotrophic Lateral Sclerosis (ASL) and FrontoTemporal Dementia (FTD) is well known. Most of reports describing ASL-FTD cases show a strong association between ALS and the behavioural form of FTD. Conversely, the association between ALS and pure Semantic Dementia or Progressive Non-Fluent Aphasia (PNFA) is extremely rare, ranging from 1 to 3%. A clinical phenotype characterized by a rapidly progressive aphasic dementia and motoneuron disease (MND) has been described in few case reports; since the updating of PNFA diagnostic criteria in 2011, no clinical report has been related. We want to describe a case of patient presented, at the onset, as PNFA who developed, one year later, ALS with bulbar onset. The patient was screened for the main genes causing or associated with MND and/or dementia but no variants with a pathogenetic effect were observed.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Demência Frontotemporal/diagnóstico , Afasia Primária Progressiva não Fluente/diagnóstico , Esclerose Lateral Amiotrófica/complicações , Demência Frontotemporal/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Afasia Primária Progressiva não Fluente/complicações
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