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1.
J AAPOS ; 28(3): 103919, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38631482

RESUMO

Lamb-Shaffer syndrome (LSS) is a rare neurodevelopmental disorder, genetically diagnosed in fewer than 100 individuals worldwide. We present a case series of 6 pediatric patients with LSS and describe its ophthalmic manifestations. Strabismus was present in 5 patients, with exotropia being most common. All subjects had significant refractive errors; 5 had astigmatism of at least 2 D. All patients had optic nerve abnormalities, including pallor (4), hypoplasia (2), and anomalous appearance (1), with retinal nerve fiber layer thinning demonstrated in a single subject. Other ophthalmic disorders detected were ptosis (1), nasolacrimal duct obstruction (1), and nystagmus (2).


Assuntos
Estrabismo , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Lactente , Estrabismo/diagnóstico , Nervo Óptico/anormalidades , Nervo Óptico/diagnóstico por imagem , Blefaroptose/diagnóstico , Obstrução dos Ductos Lacrimais/diagnóstico , Obstrução dos Ductos Lacrimais/congênito , Erros de Refração/diagnóstico , Erros de Refração/fisiopatologia , Astigmatismo/diagnóstico , Astigmatismo/fisiopatologia , Adolescente , Nistagmo Patológico/diagnóstico , Exotropia/diagnóstico , Exotropia/fisiopatologia , Exotropia/genética
2.
Polymers (Basel) ; 15(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37299211

RESUMO

The incorporation of polymeric components into aerogels based on clay produces a significant improvement in the physical and thermal properties of the aerogels. In this study, clay-based aerogels were produced from a ball clay by incorporation of angico gum and sodium alginate using a simple, ecologically acceptable mixing method and freeze-drying. The compression test showed a low density of spongy material. In addition, both the compressive strength and the Young's modulus of elasticity of the aerogels showed a progression associated to the decrease in pH. The microstructural characteristics of the aerogels were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The chemical structure was studied by infrared spectroscopy with Fourier transform (FTIR). The TGA curves from a non-oxidizing atmosphere indicated that the clay had a mass loss of 9% above 500 °C and that due to the presence of polysaccharides, the aerogels presented a decomposition of 20% at temperatures above 260 °C. The DSC curves of the aerogels demonstrated a displacement in higher temperatures. In conclusion, the results showed that aerogels of ball clay with the incorporation of polysaccharides, which are still minimally studied, have potential application as thermal insulation considering the mechanical and thermal results obtained.

4.
Angew Chem Int Ed Engl ; 62(21): e202301356, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36944060

RESUMO

We report the synthesis and characterization of a novel type of nanohoop, consisting of a cycloparaphenylene derivative incorporating a curved heptagon-containing π-extended polycyclic aromatic hydrocarbon (PAH) unit. We demonstrate that this new macrocycle behaves as a supramolecular receptor of curved π-systems such as fullerenes C60 and C70 , with remarkably large binding constants (ca. 107  M-1 ), as estimated by fluorescence measurements. Nanosecond and femtosecond spectroscopic analysis show that these host-guest complexes are capable of quasi-instantaneous charge separation upon photoexcitation, due to the ultrafast charge transfer from the macrocycle to the complexed fullerene. These results demonstrate saddle-shaped PAHs with dibenzocycloheptatrienone motifs as structural components for new macrocycles displaying molecular receptor abilities and versatile photochemical responses with promising electron-donor properties in host-guest complexes.

5.
Sci Total Environ ; 855: 158850, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36411602

RESUMO

Rapid growth in the aquaculture industry and corresponding increases in nutrient and organic carbon levels in coastal regions can lead to eutrophication and increased greenhouse gas emissions. Macroalgae are the organisms primarily responsible for the capture of CO2 and removal of nutrients from coastal waters. In the current study, we developed a novel wastewater treatment system in which the red macroalga, Sarcordia suae, is used to capture CO2 under thermostatic conditions in subtropical regions. In 2020 (without temperature control), the carbon capture rate (CCR) of Sarcordia suae varied considerably with the season: winter/spring (2.1-3.9 g-C m-2 d-1) and summer (0.09 g-C m-2 d-1). In 2021, solar powered cooling reduced summer seawater temperatures from 31 to 33 °C to 23-25 °C with a corresponding increase in the mean CCR: winter/spring (2-7 g-C m-2 d-1) and summer (1.33 g-C m-2 d-1). The proposed aquaculture wastewater system proved highly efficient in removing nitrogen (20.7 mg-N g-1 DW d-1, DW = dry weight) and phosphorus (4.4 mg-P g-1 DW d-1). Furthermore, the high density of Sarcodia (1.10 ± 0.03 g cm-3) would permit the harvesting and subsequent dumping of Sarcodia in deep off-shore waters. This study demonstrated a low-cost land-based seaweed cultivation system for capturing CO2 and excess nutrients from aquaculture wastewater year-round under temperature controlled environments in subtropical regions.


Assuntos
Alga Marinha , Energia Solar , Águas Residuárias , Carbono , Dióxido de Carbono , Aquicultura
6.
J Biomed Mater Res B Appl Biomater ; 110(4): 743-754, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34632693

RESUMO

The present work aimed to synthesize and verify the effectiveness of the polyhydroxybutyrate and norbixin membrane as a scaffold in bone defects induced in the tibia of rats. Twenty-four male Rattus norvegicus rats were used, divided into control and membrane groups. After anesthesia, a bone defect was induced in the right tibia, followed by the implantation of the biomaterial at the site of the lesion only in the membrane group, with euthanasia after 15 and 30 days of the experiment. The deposition of organic and inorganic matrix, the quality of newly formed bone tissue and the morphology of the bone defect were measured. After 15 days of the experiment, the biomaterial significantly influenced the deposition of hydroxyapatite crystals, the formation of collagen I matrix and mineralization content in relation to the control group, in addition to the abbreviation of the inflammatory process and superior quality of the newly formed bone tissue. After 30 days, only the membrane group had fully completed its repair process. The biomaterial acted as a scaffold in the regeneration of the guided bone defect by accelerating the synthesis of collagen matrix, mineralization content, density, and maturity when compared to the control group.


Assuntos
Regeneração Óssea , Durapatita , Animais , Materiais Biocompatíveis/química , Carotenoides , Durapatita/química , Masculino , Ratos
7.
Chem Commun (Camb) ; 56(84): 12813-12816, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32966400

RESUMO

Thiele (Th) and tetrabenzo-Chichibabin (TBC) derivatives with terminal dibenzocycloheptatriene (DBHept) units were prepared. A clear correlation between their electronic and molecular structures was stablished. Insights into their closed- or open-shell ground states were gained, where particular contribution of the heptagonal carbocycles as end-groups was proved. Remarkably, a thermally accessible triplet diradical configuration was confirmed for the DBHept-TBC compound.

8.
Angew Chem Int Ed Engl ; 59(35): 15124-15128, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32428338

RESUMO

A cyclophane is reported incorporating two units of a heptagon-containing extended polycyclic aromatic hydrocarbon (PAH) analogue of the hexa-peri-hexabenzocoronene (HBC) moiety (hept-HBC). This cyclophane represents a new class of macrocyclic structures that incorporate for the first time seven-membered rings within extended PAH frameworks. The saddle curvature of the hept-HBC macrocycle units induced by the presence of the nonhexagonal ring along with the flexible alkyl linkers generate a cavity with shape complementarity and appropriate size to enable π interactions with fullerenes. Therefore, the cyclophane forms host-guest complexes with C60 and C70 with estimated binding constants of Ka =420±2 m-1 and Ka =(6.49±0.23)×103 m-1 , respectively. As a result, the macrocycle can selectively bind C70 in the presence of an excess of a mixture of C60 and C70 .

9.
Angew Chem Int Ed Engl ; 59(18): 7139-7145, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32159924

RESUMO

A new family of distorted ribbon-shaped nanographenes was designed, synthesized, and their optical and electrochemical properties were evaluated, pointing out an unprecedented correlation between their structural characteristics and the two-photon absorption (TPA) responses and electrochemical band gaps. Three nanographene ribbons have been prepared: a seven-membered-ring-containing nanographene presenting a tropone moiety at the edge, its full-carbon analogue, and a purely hexagonal one. We have found that the TPA cross-sections and the electrochemical band gaps of the seven-membered-ring-containing compounds are higher and lower, respectively, than those of the fully hexagonal polycyclic aromatic hydrocarbon (PAH). Interestingly, the inclusion of additional curvature has a positive effect in terms of non-linear optical properties of those ribbons.

10.
Clin Transl Oncol ; 22(9): 1517-1523, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32048159

RESUMO

BACKGROUND (OR PURPOSE): Nivolumab has been shown to be effective for the treatment of second-line mRCC. The present study has investigated the effectiveness and safety of nivolumab in real-world Eastern Spanish patients with advanced mRCC at TKI progression. PATIENTS AND METHODS: A retrospective review of mRCC patients treated with nivolumab as a second-line treatment was performed. Analyzed variables included age, sex, ECOG (quality of life scale designed by the Eastern Cooperative Oncology Group), histology, nephrectomy, location of metastases, number of metastasis locations, previous treatments, analytical data from the standard blood count and biochemistry, and response to treatment. RESULTS: 98 patients from 18 sites in Spain were retrospectively reviewed. The majority of patients were male (75%), had ECOG 0-1 (90.6%), had no brain metastasis (91.4%), had undergone one prior systemic regimen (94.3%), and were current/former smokers (97.1%). Fourteen patients (13.1%) had non-clear cell histology, seven (7.1%) had poor-IMDC prognostic group characteristics, 13 patients (13.1%) had liver metastasis and 35 (35.7%) had bone lesions. All patients received prior systemic therapy (63.3% sunitinib, 34.7% pazopanib). During the study, a median of eight doses of nivolumab was given (range 2-62) and 11 patients received more than 12 doses. Eleven patients (11.2%) received nivolumab as a third or fourth line of treatment. Median duration of therapy was 3.6 months (range 0.5-29.3). Confirmed response rate was 25%. Median progression free survival was 7.8 months (range 1.2-12.1). Median overall survival was 16.3 months (range 1.7-29.3). After discontinuation of treatment, 27.58% of the patients received subsequent systemic cancer therapy. Side effects were mostly grade 1-2 (7.2% had hypothyroidism and 6.2% liver toxicity, 4% had nephritis and 2% hypophysitis). Two cases of grade 3-4 adverse events (2%) were reported. CONCLUSION: Benefit/risk profile of nivolumab in Eastern-Spanish real-world population with mRCC after tyrosine-kinase inhibitors was consistent with prior real-life studies reported as well as pivotal study.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Nivolumabe/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Seguimentos , Humanos , Neoplasias Renais/epidemiologia , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Retrospectivos , Espanha/epidemiologia , Taxa de Sobrevida
11.
Chemistry ; 26(17): 3776-3781, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-31917497

RESUMO

A new persistent organic free radical has been synthetized with Br atoms occupying the ortho- and para-positions of a trityl core. After the isolation of its two propeller-like atropisomers, Plus (P) and minus (M), their absolute configurations were assigned by a combination of theoretical and experimental data. Remarkably, no hints of racemization were observed up to 60 °C for more than two hours, due to the higher steric hindrance imposed by the bulky Br atoms. Therefore, when compared to its chlorinated homologue (t1/2 =18 s at 60 °C), an outstanding stability against racemization was achieved. A circularly polarized luminescence (CPL) response of both enantiomers was detected. This free radical shows a satisfactory luminescent dissymmetry factor (|glum (592 nm)|≈0.7×10-3 ) despite its pure organic nature and low luminescence quantum yield (LQY). Improved organic magnetic CPL emitters derived from the reported structure can be envisaged thanks to the wide possibilities that Br atoms at para-positions offer for further functionalization.

12.
Lifetime Data Anal ; 26(2): 221-244, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30968271

RESUMO

Frailty models are generally used to model heterogeneity between the individuals. The distribution of the frailty variable is often assumed to be continuous. However, there are situations where a discretely-distributed frailty may be appropriate. In this paper, we propose extending the proportional hazards frailty models to allow a discrete distribution for the frailty variable. Having zero frailty can be interpreted as being immune or cured (long-term survivors). Thus, we develop a new survival model induced by discrete frailty with zero-inflated power series distribution, which can account for overdispersion. A numerical study is carried out under the scenario that the baseline distribution follows an exponential distribution, however this assumption can be easily relaxed and some other distributions can be considered. Moreover, this proposal allows for a more realistic description of the non-risk individuals, since individuals cured due to intrinsic factors (immune) are modeled by a deterministic fraction of zero-risk while those cured due to an intervention are modeled by a random fraction. Inference is developed by the maximum likelihood method for the estimation of the model parameters. A simulation study is performed in order to evaluate the performance of the proposed inferential method. Finally, the proposed model is applied to a data set on malignant cutaneous melanoma to illustrate the methodology.


Assuntos
Fragilidade , Funções Verossimilhança , Análise de Sobrevida , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Stat Methods Med Res ; 29(7): 2015-2033, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31625453

RESUMO

Response variables in medical sciences are often bounded, e.g. proportions, rates or fractions of incidence of some disease. In this work, we are interested to study if some characteristics of the population, e.g. sex and race which can explain the incidence rate of colorectal cancer cases. To accommodate such responses, we propose a new class of regression models for bounded response by considering a new distribution in the open unit interval which includes a new parameter to make a more flexible distribution. The proposal is to obtain compound power normal distribution as a base distribution with a quantile transformation of another family of distributions with the same support and then is to study some properties of the new family. In addition, the new family is extended to regression models as an alternative to the regression model with a unit interval response. We also present inferential procedures based on the Bayesian methodology, specifically a Metropolis-Hastings algorithm is used to obtain the Bayesian estimates of parameters. An application to real data to illustrate the use of the new family is considered.


Assuntos
Neoplasias Colorretais , Teorema de Bayes , Neoplasias Colorretais/epidemiologia , Humanos , Incidência , Distribuição Normal
14.
Angew Chem Int Ed Engl ; 58(45): 16282-16288, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31518486

RESUMO

Chiroptical properties of two chiral atropisomers of propeller-like trityl-based radical derivatives have been analyzed. A new absolute configuration (AC) assignment has been made, according to the combination of experimental and theoretical data. In this sense, their ACs have been determined through the comparison of the Cotton effects recorded by electronic circular dichroism (ECD) with the theoretical ECD of the open shell structures obtained by TD-DFT calculations. Finally, their circularly polarized luminescence (CPL) responses have been addressed. Remarkably, this is the first description of organic free radicals as intrinsic CPL emitters. Opposite signed CPL has been detected for each pair of conformers, with acceptable luminescent dissymmetry factors (|glum |≈0.5-0.8×10-3 ) considering their pure organic nature. In fact, highly efficient chiral emissions have been demonstrated, according to the comparison of |glum | with their respective absorption anisotropy factors (|gabs |). This pioneering study lays the foundations for the optimization of new magnetically active organic chiral emitters.

15.
J Dev Orig Health Dis ; 10(3): 338-344, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30827294

RESUMO

Diabetes during pregnancy is associated with aortic remodelling in the fetus, stimulating the development of cardiovascular diseases in adult life. However, studies suggest that the use of foods high in omega-3 fatty acid, such as flaxseed oil, may reverse this effect of metabolic programming. This study aimed at investigating whether the effects of diabetes in mothers are passed on to their offspring in a gender-specific manner and whether the flaxseed oil used during pregnancy and lactation reverses or not the possible negative effects of this programming. Diabetic female rats (n = 18) were mated and allocated into three groups (n = 6): high-fat group (HG); flaxseed oil group (FOG) and control group (CG) (nondiabetic rats) during pregnancy and lactation. On the 21st day, male and female pups were weaned on a standard diet until 180 days. Aorta histomorphometry was analysed. Intima-media layer thickness was larger in FOG than CG in male (+15%) and than HG in female (+13.7%). Male FOG (+11.5%) showed higher amount of elastic fibre than CG. Maternal intake of flaxseed oil during pregnancy and lactation of diabetic mothers program the offspring to increase aorta intima-media layer thickness in adulthood and preserves aorta elastic fibres deposition in male offspring.


Assuntos
Aorta/patologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Experimental/complicações , Óleo de Semente do Linho/administração & dosagem , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Caracteres Sexuais , Animais , Animais Recém-Nascidos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Feminino , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos , Ratos Wistar , Remodelação Vascular
17.
Stat Methods Med Res ; 28(9): 2665-2680, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29984625

RESUMO

We propose a new survival model for lifetime data in the presence of surviving fraction and obtain some of its properties. Its genesis is based on extensions of the promotion time cure model, where an extra parameter controls the heterogeneity or dependence of an unobserved number of lifetimes. We construct a regression model to evaluate the effects of covariates in the cured fraction. We discuss inference aspects for the proposed model in a classical approach, where some maximum likelihood tools are explored. Further, an expectation maximization algorithm is developed to calculate the maximum likelihood estimates of the model parameters. We also perform an empirical study of the likelihood ratio test in order to compare the promotion time cure and the proposed models. We illustrate the usefulness of the new model by means of a colorectal cancer data set.


Assuntos
Neoplasias Colorretais/mortalidade , Análise de Sobrevida , Algoritmos , Neoplasias Colorretais/terapia , Humanos , Funções Verossimilhança , Modelos Estatísticos , Estados Unidos/epidemiologia
18.
J Org Chem ; 83(22): 14057-14062, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30365318

RESUMO

Racemic mixtures of boronic acid-derived salicylidenehydrazone (BASHY) complexes were enantiomerically resolved. The chiroptical properties of the stereoisomers, containing an asymmetric boron as the only stereogenic unit, are translated into mirror-imaged electronic circular dichroism spectra and circularly polarized luminescence (CPL, dissymmetry factors of 3-5 × 10-4) is observed. The spectral position of the CPL emission is determined by the push-pull character of the dye. These features expand the functional scope of the brightly emitting BASHY dye platform.

19.
Chem Commun (Camb) ; 54(27): 3359-3362, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29542798

RESUMO

Turning on the fluorescence of [3]cumulenes: we report the luminescence at room temperature upon aggregation of [3]cumulenes functionalized with propeller-like heptagon-containing polyphenylenes. These endgroups turn on the emission of a [3]cumulene by steric protection and restriction of their intramolecular rotations in the aggregates.

20.
Stat Methods Med Res ; 26(5): 2011-2028, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28656796

RESUMO

Frailty models provide a convenient way of modeling unobserved dependence and heterogeneity in survival data which, if not accounted for duly, would result incorrect inference. Gamma frailty models are commonly used for this purpose, but alternative continuous distributions are possible as well. However, with cure rate being present in survival data, these continuous distributions may not be appropriate since individuals with long-term survival times encompass zero frailty. So, we propose here a flexible probability distribution induced by a discrete frailty, and then present some special discrete probability distributions. We specifically focus on a special hyper-Poisson distribution and then develop the corresponding Bayesian simulation, influence diagnostics and an application to real dataset by means of intensive Markov chain Monte Carlo algorithm. These illustrate the usefulness of the proposed model as well as the inferential results developed here.


Assuntos
Teorema de Bayes , Idoso Fragilizado/estatística & dados numéricos , Modelos Estatísticos , Análise de Sobrevida , Idoso , Humanos , Método de Monte Carlo , Distribuição de Poisson
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