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1.
Cell Biosci ; 13(1): 132, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480151

RESUMO

BACKGROUND: Metastatic cancer cells exploit Epithelial-mesenchymal-transition (EMT) to enhance their migration, invasion, and resistance to treatments. Recent studies highlight that elevated levels of copper are implicated in cancer progression and metastasis. Clinical trials using copper chelators are associated with improved patient survival; however, the molecular mechanisms by which copper depletion inhibits tumor progression and metastasis are poorly understood. This remains a major hurdle to the clinical translation of copper chelators. Here, we propose that copper chelation inhibits metastasis by reducing TGF-ß levels and EMT signaling. Given that many drugs targeting TGF-ß have failed in clinical trials, partly because of severe side effects arising in patients, we hypothesized that copper chelation therapy might be a less toxic alternative to target the TGF-ß/EMT axis. RESULTS: Our cytokine array and RNA-seq data suggested a link between copper homeostasis, TGF-ß and EMT process. To validate this hypothesis, we performed single-cell imaging, protein assays, and in vivo studies. Here, we used the copper chelating agent TEPA to block copper trafficking. Our in vivo study showed a reduction of TGF-ß levels and metastasis to the lung in the TNBC mouse model. Mechanistically, TEPA significantly downregulated canonical (TGF-ß/SMAD2&3) and non-canonical (TGF-ß/PI3K/AKT, TGF-ß/RAS/RAF/MEK/ERK, and TGF-ß/WNT/ß-catenin) TGF-ß signaling pathways. Additionally, EMT markers of MMP-9, MMP-14, Vimentin, ß-catenin, ZEB1, and p-SMAD2 were downregulated, and EMT transcription factors of SNAI1, ZEB1, and p-SMAD2 accumulated in the cytoplasm after treatment. CONCLUSIONS: Our study suggests that copper chelation therapy represents a potentially effective therapeutic approach for targeting TGF-ß and inhibiting EMT in a diverse range of cancers.

2.
Ecol Evol ; 13(3): e9868, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36937063

RESUMO

Woody plant encroachment (WPE) has been found to alter ecosystem functioning and services in savannas. In rain-limited savannas, increasing woody cover can reduce streamflow and groundwater by altering evapotranspiration rates and rainfall partitioning, but the ecological relevance of this impact is not well known. This study quantified the altered partitioning of rainfall by two woody plant structural types (fine- and broad-leaved trees) across a gradient of encroachment in a semi-arid savanna in South Africa. Averaged across both plant functional types, loss of rainfall through canopy interception and subsequent evaporation roughly doubled (from 20.5% to 43.6% of total rainfall) with a roughly 13-fold increase in woody cover (from 2.4 to 31.4 m2/ha tree basal cover). Spatial partitioning changes comprised fourfold increases in stemflow (from 0.8% to 3.9% of total rainfall) and a decline in throughfall proportion of about two-fifths (from 80.2% to 47.3% of total rainfall). Changes in partitioning were dependent on plant functional type; rainfall interception by the fine-leaved multi-stemmed shrub Dichrostachys cinerea was almost double that of the broad-leaved tree Terminalia sericea at the highest levels of woody encroachment (i.e., 49.7% vs. 29.1% of total rainfall intercepted at tree basal area of 31.4 m2/ha). Partitioning was also dependent on rainfall characteristics, with the proportion of rainfall intercepted inversely related to rainfall event size and intensity. Therefore, increasing tree cover in African grassy ecosystems reduces the amount of canopy throughfall, especially beneath canopies of fine-leaved species in smaller rainfall events. Rainfall interception traits may thus confer a selective advantage, especially for fine-leaved woody plant species in semi-arid savannas.

3.
Braz J Biol ; 84: e248411, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544785

RESUMO

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.


Assuntos
Epilepsia , Estado Epiléptico , Animais , Dopamina/efeitos adversos , Epilepsia/induzido quimicamente , Masculino , Agonistas Muscarínicos/efeitos adversos , Oxidopamina/efeitos adversos , Pilocarpina/toxicidade , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/metabolismo , Estado Epiléptico/induzido quimicamente
5.
Eur Radiol ; 32(1): 424-431, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34327575

RESUMO

OBJECTIVES: The aim of this study was to evaluate the sensitivity of CT-based thermometry for clinical applications regarding a three-component tissue phantom of fat, muscle and bone. Virtual monoenergetic images (VMI) by dual-energy measurements and conventional polychromatic 120-kVp images with modern reconstruction algorithms adaptive statistical iterative reconstruction-Volume (ASIR-V) and deep learning image reconstruction (DLIR) were compared. METHODS: A temperature-regulating water circuit system was developed for the systematic evaluation of the correlation between temperature and Hounsfield units (HU). The measurements were performed on a Revolution CT with gemstone spectral imaging technology (GSI). Complementary measurements were performed without GSI (voltage 120 kVp, current 130-545 mA). The measured object was a tissue equivalent phantom in a temperature range of 18 to 50°C. The evaluation was carried out for VMI at 40 to 140 keV and polychromatic 120-kVp images. RESULTS: The regression analysis showed a significant inverse linear dependency between temperature and average HU regardless of ASIR-V and DLIR. VMI show a higher temperature sensitivity compared to polychromatic images. The temperature sensitivities were 1.25 HU/°C (120 kVp) and 1.35 HU/°C (VMI at 140 keV) for fat, 0.38 HU/°C (120 kVp) and 0.47 HU/°C (VMI at 40 keV) for muscle and 1.15 HU/°C (120 kVp) and 3.58 HU/°C (VMI at 50 keV) for bone. CONCLUSIONS: Dual-energy with VMI enables a higher temperature sensitivity for fat, muscle and bone. The reconstruction with ASIR-V and DLIR has no significant influence on CT-based thermometry, which opens up the potential of drastic dose reductions. KEY POINTS: • Virtual monoenergetic images (VMI) enable a higher temperature sensitivity for fat (8%), muscle (24%) and bone (211%) compared to conventional polychromatic 120-kVp images. • With VMI, there are parameters, e.g. monoenergy and reconstruction kernel, to modulate the temperature sensitivity. In contrast, there are no parameters to influence the temperature sensitivity for conventional polychromatic 120-kVp images. • The application of adaptive statistical iterative reconstruction-Volume (ASIR-V) and deep learning-based image reconstruction (DLIR) has no effect on CT-based thermometry, opening up the potential of drastic dose reductions in clinical applications.


Assuntos
Aprendizado Profundo , Termometria , Algoritmos , Humanos , Músculos , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X
6.
J Endourol ; 35(12): 1785-1792, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34148404

RESUMO

Introduction and Objective: Robot-assisted radical nephrectomy (RRN) is increasingly utilized as an alternative to laparoscopic radical nephrectomy (LRN), but there are concerns over costs and objective benefit. In the setting of very large renal masses (>10 cm), comparison between techniques is limited and it is unclear whether a robotic approach confers any perioperative benefit over LRN or open radical nephrectomy (ORN). In this study, perioperative outcomes of RRN, LRN, and ORN for very large renal masses are compared. Methods: Using the National Cancer Database, patients were identified who underwent radical nephrectomy for kidney tumors >10 cm diagnosed from 2010 to 2015. Patients were analyzed according to surgical approach. Perioperative outcomes, including conversion to open, length of stay, readmission rates, positive surgical margins, and 30- and 90-day mortality were compared among cohorts. Results: A total of 9288 patients met inclusion criteria (RRN = 842, LRN = 2326, ORN = 6120). Compared with ORN, recipients of RRN or LRN had similar rates of 30-day readmission and 30- and 90-day mortality. Length of hospital stay was significantly shorter in RRN (-1.73 days ±0.19; p < 0.0001) and LRN (-1.40 days ±0.12; p < 0.0001) compared with ORN. LRN had a higher rate of conversion to open compared with RRN (odds ratio 1.48; 95% confidence interval 1.10-1.98; p = 0.0087). Conversion to open from RRN or LRN added 1.3 additional days of inpatient stay. Over the study period, RRN use increased from 4.1% to 14.8%, LRN from 20.9% to 25.6%, whereas ORN use decreased from 75% to 59.6%. Conclusions: Minimally invasive approaches are increasingly utilized in very large renal masses. RRN has lower rates of conversion to open but produces comparable perioperative outcomes to LRN. Minimally invasive approaches have a shorter length of inpatient stay but otherwise report similar surgical margin status, readmission rates, and mortality rates compared with ORN.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Laparoscopia , Robótica , Carcinoma de Células Renais/cirurgia , Humanos , Neoplasias Renais/cirurgia , Tempo de Internação , Nefrectomia , Resultado do Tratamento
8.
Eur Urol Focus ; 7(1): 142-147, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31103602

RESUMO

BACKGROUND: The challenge of managing non-muscle-invasive bladder cancer (NMIBC) is its high recurrence rate. Clinical investigations have begun to explore the role of androgen suppression as an adjunct to bladder cancer (BC) treatment. OBJECTIVE: To examine the effect of androgen suppression therapy (AST) on recurrence and progression rate of risk-stratified NMIBC. DESIGN, SETTING, AND PARTICIPANTS: Male patients with NMIBC were identified retrospectively from a US institutional database between 2001 and 2017. AST included 5α-reductase inhibitor, gonadotropin-releasing hormone agonist, and antiandrogen. Patients who were exposed to AST prior to documented recurrence/progression were included in the treatment arm. BC was risk stratified to investigate the differential response to AST. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Hazard ratios (HRs) for NMIBC recurrence and progression were estimated using Cox proportional hazards multivariate regression models with stepwise method. Recurrence-free survival (RFS) and progression-free survival (PFS) were compared between groups with and without AST. RESULTS AND LIMITATIONS: We identified a total of 274 males with a median follow-up period of 3.1 yr (interquartile range [IQR] 1.5-5.2). Thirty-six patients were exposed to AST with a median duration of 1.7 yr (IQR 0.7-2.6). AST was associated with a lower risk of recurrence (HR 0.53, 95% confidence interval 0.30-0.88) as well as improved RFS (p = 0.014). However, no significant reduction of progression or improvement of PFS (p = 0.23) was found with AST. After risk stratification, all five patients who progressed in the AST cohort had high-risk disease on initial transurethral resection (TUR), whereas no patients with low/intermediate-risk disease progressed on AST. Limitations of the study include nonstandardized initiation of AST in relation to initial TUR, lack of androgen level quantification, and small sample size in the treatment arm. CONCLUSIONS: In this retrospective, single-institution study, AST was associated with a lower risk of recurrence in NMIBC. No significant association between AST and progression was found. Further investigation is warranted to define the role of AST as an adjunctive therapy for NMIBC. PATIENT SUMMARY: Non-muscle-invasive bladder cancer is a highly recurrent disease that often requires patients to undergo repeated surgical treatments. This single-institution report suggests that medical suppression of androgen may be a potential preventive therapy to reduce recurrence in certain patients.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Colestenona 5 alfa-Redutase/uso terapêutico , Recidiva Local de Neoplasia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Androgênios , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Receptores LHRH , Estudos Retrospectivos , Estados Unidos/epidemiologia , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/patologia
9.
Eur Radiol ; 31(6): 4298-4307, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33277671

RESUMO

OBJECTIVES: The implant constructs used in scoliosis surgery are often long with a high screw density. Therefore, it is generally believed that magnetic resonance imaging (MRI) should not be carried out after scoliosis surgery, with the result that computed tomography is often preferred despite the ionizing radiation involved. The objective of this study was to evaluate the MRI compatibility of long pedicle-screw-rod constructs at 1.5 T and 3 T using standardized methods of the American Society for Testing and Materials (ASTM). METHODS: Constructs between 130 and 430 mm long were systematically examined according to the ASTM standards F2182 (radio frequency-induced heating), F2119 (susceptibility artifacts), F2213 (magnetically induced torque), and F2052 (magnetically induced displacement force). RESULTS: The maximum heating in the magnetic field was 1.3 K. Heating was significantly influenced by magnetic field strength (p < 0.001), implant length (p = 0.048), and presence of cross-links (p = 0.001). The maximum artifact width for different lengths of the anatomically bent titanium rods with CoCr alloy ranged between 14.77 ± 2.93 mm (TSE) and 17.49 ± 1.82 mm (GRE) for 1.5 T and between 23.67 ± 2.39 mm (TSE) and 27.77 ± 2.37 mm (GRE) for 3 T. TiCP and TiAl showed the smallest and CoCr and CoCr Plus the largest artifact widths. The magnetically induced torque and displacement force were negligible. CONCLUSIONS: MRI following scoliosis surgery with long implant constructs is safe with the patient in supine position. Although susceptibility artifacts can severely limit the diagnostic value, the examination of other regions is possible. KEY POINTS: • Large spinal implants are not necessarily a contraindication for MRI; MR conditional status can be examined according to the ASTM standards F2182, F2119, F2213, and F2052. • A metallic pedicle-screw-rod system could be reliably and safely examined in all combinations of length (130 to 430 mm), configuration, and material in a B0 at 1.5 T and 3 T. • According to ASTM F2503, the examined pedicle-screw-rod system is MR conditional and especially the young patients can benefit from a non-ionizing radiation MRI examination.


Assuntos
Artefatos , Escoliose , Calefação , Humanos , Imageamento por Ressonância Magnética , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Torque
10.
Sci Rep ; 10(1): 17220, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057070

RESUMO

Paclitaxel drug coated balloons (DCBs) should provide optimal drug transfer exclusively to the target tissue. The aim of this study was to evaluate the particle loss by handling during angioplasty. A robotic arm was developed for systematic and reproducible drug abrasion experiments. The contact force on eight different commercially available DCB types was gradually increased, and high-resolution microscopic images of the deflated and inflated balloons were recorded. Three types of DCBs were classified: no abrasion of the drug in both statuses (deflated and inflated), significant abrasion only in the inflated status, and significant abrasion in both statuses. Quantitative measurements via image processing confirmed the qualitative classification and showed changes of the drug area between 2.25 and 45.73% (13.28 ± 14.29%) in the deflated status, and between 1.66 and 40.41% (21.43 ± 16.48%) in the inflated status. The structures and compositions of the DCBs are different, some are significantly more susceptible to drug loss. Particle loss by handling during angioplasty leads to different paclitaxel doses in the target regions for same DCB types. Susceptibility to involuntary drug loss may cause side effects, such as varying effective paclitaxel doses, which may explain variations in studies regarding the therapeutic outcome.


Assuntos
Angioplastia , Materiais Revestidos Biocompatíveis , Sistemas de Liberação de Medicamentos/instrumentação , Paclitaxel/administração & dosagem , Angioplastia/instrumentação , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Paclitaxel/efeitos adversos , Resultado do Tratamento
11.
Sci Rep ; 10(1): 3801, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32123249

RESUMO

A person may be identified by comparison between ante- and post-mortem dental panoramic radiographs (DPR). However, it is difficult to find reference material if the person is unknown. This is often the case when victims of crime or mass disaster are found. Computer vision can be a helpful solution to automate the finding of reference material in a large database of images. The purpose of the present study was to improve the automated identification of unknown individuals by comparison of ante- and post-mortem DPR using computer vision. The study includes 61,545 DPRs from 33,206 patients, acquired between October 2006 and June 2018. The matching process is based on the Speeded Up Robust Features (SURF) algorithm to find unique corresponding points between two DPRs (unknown person and database entry). The number of matching points found is an indicator for identification. All 43 individuals (100%) were successfully identified by comparison with the content of the feature database. The experimental setup was designed to identify unknown persons based on their DPR using an automatic algorithm system. The proposed tool is able to filter large databases with many entries of potentially matching partners. This identification method is suitable even if dental characteristics were removed or added in the past.


Assuntos
Automação/métodos , Antropologia Forense/métodos , Radiografia Panorâmica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Automação/instrumentação , Autopsia , Criança , Feminino , Antropologia Forense/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Panorâmica/instrumentação , Raios X , Adulto Jovem
12.
Urol Oncol ; 37(12): 877-885, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31420159

RESUMO

BACKGROUND: Contemporary randomized controlled trials exploring adjuvant chemotherapy (AC) for bladder cancer (BCa) have yielded inconsistent results due to premature termination and/or poor patient accrual. OBJECTIVE: To compare efficacy of AC vs. observation after radical cystectomy stratified by disease stage in a propensity-matched cohort. DESIGN, SETTING, AND PARTICIPANTS: We performed a retrospective study that included patients who underwent radical cystectomy for any pT, N0-1, M0 BCa from the National Cancer Data Base (2004-2014). Patients who underwent AC were 1:1 propensity matched with patients who received observation only. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Overall survival was assessed with multivariable Cox regression models where adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) were calculated. RESULTS AND LIMITATIONS: After coarsened exact 1:1 propensity matching, 3,066 patients (AC 1,533; observation 1,533) were included in the analysis. There were no significant differences in patient-, facility-, or tumor-level characteristics among cohorts. Compared with patients who underwent observation, recipients of AC had improved overall survival (aHR 0.67; 95% CI 0.61-0.74). Patients with pT2-4, pN1 disease significantly benefited from AC. Among the pN0 cohort, improved survival from AC was observed only in stages pT3 (aHR 0.67; 95% CI 0.55-0.83) and pT4 (aHR 0.70; 95% CI 0.50-0.98). CONCLUSIONS: AC was associated with improved survival in locally advanced (pT3-4, pN0) and regionally advanced (pT2-4, pN1) chemotherapy-naive BCa.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células de Transição/terapia , Cistectomia , Metástase Linfática/terapia , Neoplasias da Bexiga Urinária/terapia , Conduta Expectante/estatística & dados numéricos , Adolescente , Adulto , Idoso , Carcinoma de Células de Transição/patologia , Quimioterapia Adjuvante/estatística & dados numéricos , Conjuntos de Dados como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do Tratamento , Bexiga Urinária/patologia , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia , Adulto Jovem
13.
Hear Res ; 380: 100-107, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31234108

RESUMO

Nonlinear responses to acoustic signals arise through active processes in the cochlea, which has an exquisite sensitivity and wide dynamic range that can be explained by critical nonlinear oscillations of outer hair cells. Here we ask how the interaction of critical nonlinearities with the basilar membrane and other organ of Corti components could determine tuning properties of the mammalian cochlea. We propose a canonical oscillator model that captures the dynamics of the interaction between the basilar membrane and organ of Corti, using a pair of coupled oscillators for each place along the cochlea. We analyze two models in which a linear oscillator, representing basilar membrane dynamics, is coupled to a nonlinear oscillator poised at a Hopf instability. The coupling in the first model is unidirectional, and that of the second is bidirectional. Parameters are determined by fitting 496 auditory-nerve (AN) tuning curves of macaque monkeys. We find that the unidirectionally and bidirectionally coupled models account equally well for threshold tuning. In addition, however, the bidirectionally coupled model exhibits low-amplitude, spontaneous oscillation in the absence of stimulation, predicting that phase locking will occur before a significant increase in firing frequency, in accordance with well known empirical observations. This leads us to a canonical oscillator cochlear model based on the fundamental principles of critical nonlinear oscillation and coupling dynamics. The model is more biologically realistic than widely used linear or nonlinear filter-based models, yet parsimoniously displays key features of nonlinear mechanistic models. It is efficient enough for computational studies of auditory perception and auditory physiology.


Assuntos
Percepção Auditiva , Cóclea/inervação , Células Ciliadas Auditivas Externas/fisiologia , Audição , Modelos Neurológicos , Estimulação Acústica , Animais , Vias Auditivas/fisiologia , Simulação por Computador , Macaca , Dinâmica não Linear , Oscilometria , Fatores de Tempo
14.
Neuroscience ; 408: 68-80, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30928339

RESUMO

Thrombospondins (TSPs) are cell adhesion molecules that play an important role in the maintenance of hearing and afferent synaptic connections. Based on their reported function in restoring synaptic connections after stroke, we tested a potential role for TSP1 and TSP2 genes in repairing cochlear synapses following noise injury. We observed a tonotopic gradient in the expression of TSP1 and TSP2 mRNA in control mouse cochleae and an upregulation of these genes following noise exposure. Examining the functional sequelae of these changes revealed that afferent synaptic counts and auditory brainstem responses (ABRs) in noise-exposed TSP1 and TSP2 knockout (-/-) mice exhibited a worst recovery when compared to controls. Consistent with their tonotopic expression, TSP1-/- mice showed greater susceptibility to noise-induced hearing loss (NIHL) at 8 kHz and 16 kHz frequencies, whereas NIHL in TSP2-/- mice occurred only at mid and high frequencies. Further analysis of the ABR waveforms indicated peripheral neuronal damage in TSP2-/- but not in TSP1-/- mice. Noise trauma affecting mid to high frequencies triggered severe seizures in the TSP2-/- mice. We found that decreased susceptibility to audiogenic seizures in TSP1-/- mice was correlated with increased TSP2 protein levels in their inner ears, suggesting that TSP2 might functionally compensate for the loss of TSP1 in these mice. Our data indicate that TSP1 and TSP2 are both involved in susceptibility to NIHL, with TSP2 playing a more prominent role.


Assuntos
Limiar Auditivo/fisiologia , Cóclea/metabolismo , Perda Auditiva Provocada por Ruído/metabolismo , Trombospondina 1/metabolismo , Trombospondinas/metabolismo , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Regulação da Expressão Gênica , Perda Auditiva Provocada por Ruído/fisiopatologia , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Gânglio Espiral da Cóclea/metabolismo , Trombospondina 1/genética , Trombospondinas/genética
15.
ACS Appl Mater Interfaces ; 11(8): 8310-8318, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30701959

RESUMO

Recently, the advent of non-fullerene acceptors (NFAs) made it possible for organic solar cells (OSCs) to break the 10% efficiency barrier hardly attained by fullerene acceptors (FAs). In the past five years alone, more than hundreds of NFAs with applications in organic photovoltaics (OPVs) have been synthesized, enabling a notable current record efficiency of above 15%. Hence, there is a shift in interest toward the use of NFAs in OPVs. However, there has been little work on the stability of these new materials in devices. More importantly, there is very little comparative work on the photostability of FA versus NFA solar cells to ascertain the pros and cons of the two systems. Here, we show the photostability of solar cells based on two workhorse acceptors, in both conventional and inverted structures, namely, ITIC (as NFA) and [70]PCBM (as FA), blended with either PBDB-T or PTB7-Th polymer. We found that, irrespective of the polymer, the cell structure, or the initial efficiency, the [70]PCBM devices are more photostable than the ITIC ones. This observation, however, opposes the assumption that NFA solar cells are more photochemically stable. These findings suggest that complementary absorption should not take precedence in the design rules for the synthesis of new molecules and there is still work left to be done to achieve stable and efficient OSCs.

16.
J AAPOS ; 22(1): 66-67, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29247795

RESUMO

The management of bacterial conjunctivitis has a significant economic impact, despite the relatively benign nature of the disease. We reviewed the medical records for children diagnosed with conjunctivitis at inpatient and outpatient facilities of a tertiary university center over a 5-year period to examine the microbial trends and physician practice patterns and found that most cases of conjunctivitis were treated empirically. When cultures were performed and an organism was recovered, there were significant differences in the organism based on age. Although bacterial conjunctivitis accounted for only 10% of cases, antibiotics were dispensed in more than half of the cases. Pediatricians prescribed antibiotics for conjunctivitis more than twice as often as ophthalmologists. Less than 5% of patients who did not receive antibiotics returned to clinic within 1 month for persistent symptoms.


Assuntos
Antibacterianos/uso terapêutico , Conjuntivite Bacteriana , Padrões de Prática Médica/tendências , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Conjuntivite Bacteriana/tratamento farmacológico , Conjuntivite Bacteriana/epidemiologia , Conjuntivite Bacteriana/microbiologia , Feminino , Florida/epidemiologia , Humanos , Lactente , Prevalência , Estudos Retrospectivos
17.
Actas dermo-sifiliogr. (Ed. impr.) ; 108(9): e57-e62, nov. 2017.
Artigo em Espanhol | IBECS | ID: ibc-168144

RESUMO

El síndrome del nevus melanocítico congénito (SNMC) consiste en la proliferación anormal de melanocitos en la piel y el sistema nervioso central, y se debe a mutaciones de las células progenitoras durante el desarrollo embrionario. En muchas de estas células se han detectado mutaciones en el gen NRAS. Se exponen 5 casos de nevus melanocítico congénito gigante, 3 de ellos asociados al SNMC, en los que se ha estudiado dicha mutación. Hasta hace unos años la cirugía era el tratamiento de elección, sin embargo, sus resultados son insatisfactorios, con cirugías agresivas que no mejoran el aspecto estético y reducen mínimamente el riesgo de malignización. En el año 2013 se aprobó el trametinib en el uso del melanoma avanzado con mutaciones de NRAS. Dicho fármaco, que participa en la cascada intracelular de RAS-RAF-MEK-pERK-MAPK, podría ser útil en pacientes pediátricos con SNMC. El conocimiento más amplio de esta enfermedad permitirá crear nuevas estrategias (AU)


Congenital melanocytic nevus syndrome (CMNS) is the result of an abnormal proliferation of melanocytes in the skin and central nervous system caused by progenitor-cell mutations during embryonic development. Mutations in the NRAS gene have been detected in many of these cells. We present 5 cases of giant congenital melanocytic nevus, 3 of them associated with CMNS; NRAS gene mutation was studied in these 3 patients. Until a few years ago, surgery was the treatment of choice, but the results have proved unsatisfactory because aggressive interventions do not improve cosmetic appearance and only minimally reduce the risk of malignant change. In 2013, trametinib was approved for use in advanced melanoma associated with NRAS mutations. This drug, which acts on the intracellular RAS/RAF/MEK/pERK/MAPK cascade, could be useful in pediatric patients with CMNS. A better understanding of this disease will facilitate the development of new strategies (AU)


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Nevo Pigmentado/congênito , Melanose/genética , Síndromes Neurocutâneas/genética , Síndrome do Hamartoma Múltiplo/congênito , Mutação/genética , Marcadores Genéticos , Melanócitos
18.
PLoS One ; 12(10): e0186238, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29020119

RESUMO

The most efficient method to expand limbal stem cells (LSCs) in vitro for clinical transplantation is to culture single LSCs directly on growth-arrested mouse fibroblast 3T3 cells. To reduce possible xenobiotic contamination from 3T3s, primary human adipose-derived stem cells (ASCs) were examined as feeder cells to support the expansion of LSCs in vitro. To optimize the ASC-supported culture, freshly isolated limbal epithelial cells in the form of single cells (SC-ASC) or cell clusters (CC-ASC) were cultured using three different methods: LSCs seeded directly on feeder cells, a 3-dimensional (3D) culture system and a 3D culture system with fibrin (fibrin 3D). The expanded LSCs were examined at the end of a 2-week culture. The standard 3T3 culture served as control. Expansion of SC-ASC showed limited proliferation and exhibited differentiated morphology. CC-ASC generated epithelial cells with undifferentiated morphology in all culture methods, among which CC-ASC in 3D culture supported the highest cell doubling (cells doubled 9.0 times compared to cells doubled 4.9 times in control) while maintained the percentage of putative limbal stem/progenitor cells compared to the control. There were few cell-cell contacts between cultured LSCs and ASCs in 3D CC-ASC. In conclusion, ASCs support the growth of LSCs in the form of cell clusters but not in single cells. 3D CC-ASC could serve as a substitute for the standard 3T3 culture to expand LSCs.


Assuntos
Tecido Adiposo/citologia , Limbo da Córnea/citologia , Células-Tronco/citologia , Células 3T3 , Adulto , Idoso , Animais , Biomarcadores/metabolismo , Agregação Celular , Comunicação Celular , Contagem de Células , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Alimentadoras/citologia , Humanos , Imuno-Histoquímica , Camundongos , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto Jovem
19.
Ophthalmic Surg Lasers Imaging Retina ; 48(8): 632-637, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28810038

RESUMO

BACKGROUND AND OBJECTIVE: To report the visual and anatomical outcomes and microbiologic spectrum of culture-positive endophthalmitis in open globe injuries (OGIs) with or without intraocular foreign bodies (IOFBs). PATIENTS AND METHODS: A retrospective, interventional case series of OGIs (n = 718) treated between 2004 and 2015. Patients underwent a management protocol for OGI, including systemic broad-spectrum antibiotics, on presentation. RESULTS: Culture-positive cases of endophthalmitis after open globe repair occurred in 2.1% of eyes (n = 15 of 718 eyes); two eyes had evidence of endophthalmitis on presentation. The most common organism was Staphylococcus species (five of 17 eyes). An IOFB was present in 6.8% of eyes (n = 49 of 718 eyes). All of these eyes received prophylactic intravitreal antimicrobials. In eyes with IOFB, the rate of culture-positive endophthalmitis after initial globe repair was 8.1% (n = 4 of 49 eyes) versus 1.6% (n = 11 of 669 eyes) in eyes without IOFB (P < .01). CONCLUSION: Culture-positive endophthalmitis was identified after OGIs more often in eyes with a concurrent IOFB. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:632-637.].


Assuntos
Bactérias/isolamento & purificação , Endoftalmite/microbiologia , Corpos Estranhos no Olho/complicações , Infecções Oculares Bacterianas/microbiologia , Ferimentos Oculares Penetrantes/complicações , Órbita/lesões , Infecção dos Ferimentos/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/patogenicidade , Endoftalmite/diagnóstico , Endoftalmite/etiologia , Corpos Estranhos no Olho/diagnóstico , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/etiologia , Ferimentos Oculares Penetrantes/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Virulência , Acuidade Visual , Infecção dos Ferimentos/etiologia , Infecção dos Ferimentos/microbiologia , Adulto Jovem
20.
Actas Dermosifiliogr ; 108(9): e57-e62, 2017 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28110826

RESUMO

Congenital melanocytic nevus syndrome (CMNS) is the result of an abnormal proliferation of melanocytes in the skin and central nervous system caused by progenitor-cell mutations during embryonic development. Mutations in the NRAS gene have been detected in many of these cells. We present 5 cases of giant congenital melanocytic nevus, 3 of them associated with CMNS; NRAS gene mutation was studied in these 3 patients. Until a few years ago, surgery was the treatment of choice, but the results have proved unsatisfactory because aggressive interventions do not improve cosmetic appearance and only minimally reduce the risk of malignant change. In 2013, trametinib was approved for use in advanced melanoma associated with NRAS mutations. This drug, which acts on the intracellular RAS/RAF/MEK/pERK/MAPK cascade, could be useful in pediatric patients with CMNS. A better understanding of this disease will facilitate the development of new strategies.


Assuntos
Nevo Pigmentado/congênito , Neoplasias Cutâneas/congênito , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Códon/genética , Síndrome de Dandy-Walker/diagnóstico por imagem , Síndrome de Dandy-Walker/etiologia , Síndrome de Dandy-Walker/cirurgia , Epilepsia do Lobo Temporal/etiologia , Paralisia Facial/etiologia , Evolução Fatal , Feminino , Genes ras , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Melanose/congênito , Melanose/diagnóstico por imagem , Melanose/genética , Melanose/patologia , Mutação de Sentido Incorreto , Síndromes Neurocutâneas/congênito , Síndromes Neurocutâneas/diagnóstico por imagem , Síndromes Neurocutâneas/genética , Síndromes Neurocutâneas/patologia , Neuroimagem , Nevo Pigmentado/genética , Nevo Pigmentado/patologia , Especificidade de Órgãos , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
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