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1.
Vasc Health Risk Manag ; 20: 21-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38222901

RESUMO

Background: Intracerebral hemorrhage (ICH) is a serious condition characterized by bleeding within the brain tissue. Although the use of sildenafil, a vasodilator agent for erectile dysfunction, has been associated with rare cases of ICH, the combination of sildenafil usage and smoking as risk factors for ICH has not yet been reported. This case report describes the occurrence of ICH in a patient with a history of both sildenafil usage and heavy smoking. Case Presentation: A 53-year-old male, with a history of smoking and regular sildenafil use, was brought to the emergency department due to loss of consciousness with right-side weakness, he initially experienced with nausea, vomiting and dizziness after taking sildenafil 100mg tablet once. The Glasgow Coma Score (GCS) was 10 with side hemiparesis. Non-contrast CT revealed left thalamic acute hemorrhage with ventricular extension. Furthermore, a head CT angiography ruled out any vascular anomalies after that the patient was admitted to the intensive care unit (ICU) for conservative management. After three days on clinical and neurological improvement, the patient was transferred to the inpatient ward for further management, monitoring and physiotherapy. On day 6, the patient was discharged and planned for flow up. Conclusion: This rare case highlights the need for further research and awareness regarding the potential risks associated with the combination of sildenafil and heavy smoking. Healthcare professionals should carefully evaluate the individual risk factors of patients, educate them about potential complications, and consider alternative treatments if necessary. Additionally, patients should be encouraged to quit smoking and adopt a healthy lifestyle to minimize the risk of cerebrovascular events.


Assuntos
Fumar Cigarros , Disfunção Erétil , Masculino , Humanos , Pessoa de Meia-Idade , Citrato de Sildenafila/efeitos adversos , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/diagnóstico por imagem , Fatores de Risco
2.
Soft Matter ; 19(21): 3975-3982, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37222455

RESUMO

The growth kinetics of the adsorbed layer of poly(2-vinylpiridine) on silicon oxide is studied using a leaching technique which is based on the Guiselin brushes approach. The adsorbed layer is grown from a 200 nm thick P2VP film for several annealing time periods at different annealing temperatures. Then the film is solvent-leached, and the height of the remaining adsorbed layer is measured by atomic force microscopy. At the lowest annealing temperature only a linear growth regime is observed, followed by a plateau. Here, the molecular mobility of segments is too low to allow for a logarithmic growth. At higher annealing temperatures, both linear and logarithmic growth regimes are observed, followed by a plateau. At even higher annealing temperatures, the growth kinetics of the adsorbed layer changes. A linear growth followed by logarithmic growth kinetics is observed for short annealing time periods. For longer annealing time periods, an upturn of the growth kinetics is observed. At the highest annealing temperature, only a logarithmic growth regime is found. The change in the growth kinetics is discussed by an alteration in the structure of the adsorbed layer. Moreover, the interaction between the polymer segments and the substrate becomes weaker due to both enthalpic and entropic effects. Therefore, at high annealing temperatures the polymer segments might more easily desorb from the substrate.

3.
RSC Adv ; 13(21): 14473-14483, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37179996

RESUMO

The glass transition behavior of thin films of poly(bisphenol A carbonate) (PBAC) was studied employing ellipsometry. The glass transition temperature increases with the reduction of the film thickness. This result is attributed to the formation of an adsorbed layer with a reduced mobility compared to bulk PBAC. Therefore, for the first time, the growth kinetics of the adsorbed layer of PBAC was investigated, prepared by leaching samples from a 200 nm thin film which were annealed for several times at three different temperatures. The thickness of each prepared adsorbed layer was measured by multiple scans using atomic force microscopy (AFM). Additionally, an unannealed sample was measured. Comparison of the measurements of the unannealed and the annealed samples provides proof of a pre-growth regime for all annealing temperatures which was not observed for other polymers. For the lowest annealing temperature after the pre-growth stage only a growth regime with a linear time dependence is observed. For higher annealing temperatures the growth kinetics changes from a linear to a logarithmic growth regime at a critical time. At the longest annealing times the films showed signs of dewetting where segments of the adsorbed film were removed from the substrate (dewetting by desorption). The dependence of the surface roughness of the PBAC surface on annealing time also confirmed that the films annealed at highest temperatures for the longest times desorbed from the substrate.

4.
BMC Public Health ; 22(1): 2438, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575430

RESUMO

BACKGROUND: In recognition of the risk factors common between oral diseases and various chronic conditions and the intersection between oral health and some sustainable development goals, the current cross-sectional study was designed to quantify the burden of dental caries and identify factors associated with its occurrence in permanent teeth. METHODS: Using data from Egypt's population-based survey (2013-2014), two individual-level outcomes; past caries experience (DMFT > 0) and presence of untreated carious lesions (DT > 0) were assessed using the WHO basic methods for oral health surveys. Information on potential explanatory variables including sociodemographic characteristics, exposure to fluoridated water, dental attendance, and dental anxiety was gathered using a structured questionnaire. Stratified multistage cluster random sampling was used to recruit survey participants. Multivariable logistic regression was performed to identify significant potential risk factors for caries in the permanent dentition of Egyptians. FINDINGS: A total of 9,457 participants were included of which 70.3% had at least one untreated carious lesion. After adjusting for all covariates, analphabetic Egyptians were found to have significantly higher odds of caries experience in permanent dentition DMFT > 0 (OR 1.54, 95% CI [1.20-1.98]), DT > 0 (OR 1.62, 95% CI [1.32-2.00]). Males, however, had significantly lower caries risk DMFT > 0 (OR 0.75, 95% CI [0.67-0.85]), DT > 0 (OR 0.81, 95% CI [0.73-0.89]) when compared to females. Regarding age, mean DMFT scores were significantly lower in age groups (6-15 years) (OR 0.03, 95% CI [0.014; 0.082]), (16- 20 years) (OR 0.09, 95% CI [0.037; 0.23]), and (21-35 years) (OR 0.22, 95% CI [0.09; 0.53]) than among people ≥ 60 years. CONCLUSION: Addressing individual-level caries risk factors should be complemented by addressing upstream factors to reduce burden of untreated dental caries among Egyptians.


Assuntos
Cárie Dentária , Dentição Permanente , Masculino , Feminino , Humanos , Criança , Adolescente , Egito/epidemiologia , Estudos Transversais , Cárie Dentária/epidemiologia , Índice CPO , Prevalência
5.
Clin Ophthalmol ; 16: 2765-2773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36039106

RESUMO

Purpose: To report clinical, serological, and histopathological findings in Egyptian patients with dacryoadenitis associated with ImmunoglobulinG4-related disease (IgG4-RD). Methods: We retrospectively revised medical records of patients presented to Al-Azhar University Hospitals with lacrimal gland (LG) swelling between June 2016 and February 2022. We included patients with definite IgG4-related disease (IgG4-RD) diagnosis and excluded those with possible, probable, or unlikely IgG4-RD based on The Japanese Ministry of Health, Labour, and Welfare's 2011 guidelines. Results: Sixteen cases were included in the study (Fourteen females and two males, mean age 39.2±12.2 years); Seven cases met the criteria of Mikulicz disease, and nine cases met full clinical, serological, and histopathological criteria. Mean reported serum IgG was 1792.5 ± 313.7 (range 1063-2134) mg/dl, mean serum IgG4 was 576.25±215.3 (range 112-841) mg/dl, and mean Serum IgG4/IgG ratio was 31.9 ± 12.4%. The mean number of IgG4+ plasma cells/HPF was 74 ± 21.2, and the mean IgG4+ plasma cell percentage was 55 ± 9.7%. Serum IgG4 level showed a positive correlation to tissue IgG4+plasma cell percentage, while serum IgG4/IgG ratio positively correlated to both percentage and number of IgG4+plasma cells. Steroids had a good initial response, but recurrences were common. Conclusion: A considerable proportion of patients with lacrimal gland swelling fall within the range of IgG4-RD. Proper diagnosis requires clinical, serological, and histopathologic correlation. Patients require long follow-up periods.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37641604

RESUMO

Background: In patients with type 2 diabetes mellitus, the development of diabetic retinopathy (DR) correlates positively with elevated serum chemerin levels. This study was aimed at investigating the probable association between the serum chemerin level and the development of DR in patients with type 1 diabetes mellitus (T1DM). Methods: In this cross-sectional study, we included Egyptians and classified them into four groups: group 1, including healthy individuals; group 2, including patients with T1DM without DR; group 3, including patients with T1DM with non-proliferative DR (NPDR); and group 4, including patients with T1DM with proliferative DR (PDR). The assessment included best-corrected distance visual acuity assessment, slit-lamp biomicroscopy, funduscopy, fundus fluorescein angiography, and macular ocular coherence tomography. Fasting blood samples were obtained from all participants to measure serum chemerin, glycated hemoglobin (HbA1c), total cholesterol, triglyceride, and creatinine levels. Serum chemerin levels were compared among the groups, and their correlations with age, duration of diabetes, HbA1c, total cholesterol, triglyceride, and creatinine levels were analyzed. Results: We recruited 209 participants, including 46 healthy individuals in group 1, 52 patients (T1DM and no DR) in group 2, 61 patients (T1DM and NPDR) in group 3, and 50 patients (T1DM and PDR) in group 4, with comparable mean ages and sex ratios among groups. The diabetes duration, body mass index, HbA1c, total cholesterol, triglyceride, and serum chemerin levels differed significantly among the groups (all P < 0.001), whereas the creatinine level did not (P > 0.05). The serum chemerin level was significantly higher in group 4 than in groups 3 and 2, in group 3 than in group 2, and in groups 3 and 4 than in group 1 (all P < 0.001). However, it was comparable between groups 1 and 2 (P > 0.05). It correlated with the duration of T1DM and HbA1c, total cholesterol, triglyceride, and creatinine levels but not with age. Conclusions: Patients with T1DM with DR showed higher serum chemerin levels than those with T1DM without DR or healthy individuals. Serum chemerin levels were higher in those with PDR than in those with NPDR. Thus, serum chemerin levels are a potential biomarker of the development and severity of DR in patients with T1DM. Nevertheless, future diagnostic accuracy studies are required to confirm these potential applications.

7.
Polymers (Basel) ; 13(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069948

RESUMO

Epoxy nanocomposites are promising materials for industrial applications (i.e., aerospace, marine and automotive industry) due to their extraordinary mechanical and thermal properties. Here, the effect of hollow halloysite nanotubes (HNT) on an epoxy matrix (Ep) was the focus of the study. The structure and molecular mobility of the nanocomposites were investigated using a combination of X-ray scattering, calorimetry (differential (DSC) and fast scanning calorimetry (FSC)) and dielectric spectroscopy. Additionally, the effect of surface modification of HNT (polydopamine (PDA) and Fe(OH)3 nanodots) was considered. For Ep/HNT, the glass transition temperature (Tg) was decreased due to a nanoparticle-related decrease of the crosslinking density. For the modified system, Ep/m-HNT, the surface modification resulted in enhanced filler-matrix interactions leading to higher Tg values than the pure epoxy in some cases. For Ep/m-HNT, the amount of interface formed between the nanoparticles and the matrix ranged from 5% to 15%. Through BDS measurements, localized fluctuations were detected as a ß- and γ-relaxation, related to rotational fluctuations of phenyl rings and local reorientations of unreacted components. A combination of calorimetry and dielectric spectroscopy revealed a dynamic and structural heterogeneity of the matrix, as confirmed by two glassy dynamics in both systems, related to regions with different crosslinking densities.

8.
Diagnostics (Basel) ; 11(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922543

RESUMO

The study sought to assess whether the soft tissue facial profile measurements of direct Cone Beam Computed Tomography (CBCT) and wrapped CBCT images of non-standardized facial photographs are accurate compared to the standardized digital photographs. In this cross-sectional study, 60 patients with an age range of 18-30 years, who were indicated for CBCT, were enrolled. Two facial photographs were taken per patient: standardized and random (non-standardized). The non-standardized ones were wrapped with the CBCT images. The most used soft tissue facial profile landmarks/parameters (linear and angular) were measured on direct soft tissue three-dimensional (3D) images and on the photographs wrapped over the 3D-CBCT images, and then compared to the standardized photographs. The reliability analysis was performed using concordance correlation coefficients (CCC) and depicted graphically using Bland-Altman plots. Most of the linear and angular measurements showed high reliability (0.91 to 0.998). Nevertheless, four soft tissue measurements were unreliable; namely, posterior gonial angle (0.085 and 0.11 for wrapped and direct CBCT soft tissue, respectively), mandibular plane angle (0.006 and 0.0016 for wrapped and direct CBCT soft tissue, respectively), posterior facial height (0.63 and 0.62 for wrapped and direct CBCT soft tissue, respectively) and total soft tissue facial convexity (0.52 for both wrapped and direct CBCT soft tissue, respectively). The soft tissue facial profile measurements from either the direct 3D-CBCT images or the wrapped CBCT images of non-standardized frontal photographs were accurate, and can be used to analyze most of the soft tissue facial profile measurements.

9.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21253892

RESUMO

BackgroundWillingness of healthcare workers to be vaccinated is an important factor to be consider for successful COVID-19 vaccination programme. Our study aimed to understand the willingness of health workers to receive COVID-19 vaccine and associated concerns across 10 countries in the Eastern Mediterranean Region (EMRO). MethodA cross-sectional study was conducted in January 2021 among healthcare workers using an online survey. A total of 2806 health workers (Physicians, Nurses and Pharmacists) completed and returned the informed consent along with the questionnaire electronically. Data were analyzed using IBM SPSS software package version 20.0. S ResultsMore than half of the respondents (58.0%) were willing to receive COVID-19 vaccine, even if the vaccination is not mandatory for them. On the other hand, 25.7% of respondents were not willing to undertake COVID-19 vaccination while 16.3 % answered undecided. The top three reasons for not intending to be vaccinated were unreliability of COVID-19 vaccine clinical trials (62.0%), fear of the side effects of the vaccine (45.3%), and that COVID-19 vaccine will not give immunity for a long period of time (23.1%). ConclusionOverall, our study revealed suboptimal acceptance of COVID-19 vaccine among our respondents in the EMRO region. Significant refusal of COVID-19 vaccine among healthcare professionals can reverse hard-won progress in building public trust in COVID-19 vaccination program. Our findings suggest the need to develop tailored strategies to address concerns identified in the study in order to ensure optimal vaccine acceptance among healthcare workers in the EMRO.

10.
Proc Natl Acad Sci U S A ; 114(15): 3837-3842, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28320948

RESUMO

Photosynthesis is responsible for the photochemical conversion of light into the chemical energy that fuels the planet Earth. The photochemical core of this process in all photosynthetic organisms is a transmembrane protein called the reaction center. In purple photosynthetic bacteria a simple version of this photoenzyme catalyzes the reduction of a quinone molecule, accompanied by the uptake of two protons from the cytoplasm. This results in the establishment of a proton concentration gradient across the lipid membrane, which can be ultimately harnessed to synthesize ATP. Herein we show that synthetic protocells, based on giant lipid vesicles embedding an oriented population of reaction centers, are capable of generating a photoinduced proton gradient across the membrane. Under continuous illumination, the protocells generate a gradient of 0.061 pH units per min, equivalent to a proton motive force of 3.6 mV⋅min-1 Remarkably, the facile reconstitution of the photosynthetic reaction center in the artificial lipid membrane, obtained by the droplet transfer method, paves the way for the construction of novel and more functional protocells for synthetic biology.


Assuntos
Células Artificiais/química , Fotossíntese/fisiologia , Complexo de Proteínas do Centro de Reação Fotossintética/química , Prótons , Catálise , Concentração de Íons de Hidrogênio , Luz , Força Próton-Motriz , Quinonas/química
11.
ACS Appl Mater Interfaces ; 7(7): 3902-9, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25646868

RESUMO

Four linear terarylene molecules (i) 4-nitro-terphenyl-4″-methanethiol (NTM), (ii) 4-nitro-terphenyl-3″,5″-dimethanethiol (NTD), (iii) ([1,1';4',1″] terphenyl-3,5-diyl)methanethiol (TM), and (iv) ([1,1';4',1″] terphenyl-3,5-diyl)dimethanethiol (TD) have been synthesized and their self-assembled monolayers (SAMs) have been obtained on polycrystalline gold. NTM and NTD SAMs have been characterized by X-ray photoelectron spectroscopy, Kelvin probe measurements, electrochemistry, and contact angle measurements. The terminal nitro group (-NO2) is irreversibly reduced to hydroxylamine (-NHOH), which can be reversibly turned into nitroso group (-NO). The direct comparison between NTM/NTD and TM/TD SAMs unambiguously shows the crucial influence of the nitro group on electrowetting properties of polycrystalline Au. The higher grade of surface tension related to NHOH has been successfully exploited for basic operations of digital µ-fluidics, such as droplets motion and merging.

12.
ACS Appl Mater Interfaces ; 6(1): 153-8, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24328296

RESUMO

Single-walled carbon nanotubes (SWCNTs) were suspended in 1,2-dichloroethane by noncovalent functionalization with a low-band-gap conjugated polymer 1 alternating dialkoxyphenylene-bisthiophene units with benzo[c][2,1,3]thiadiazole monomeric units. The suspended 1/SWCNT blend was transferred onto different solid substrates by the Langmuir-Schaefer deposition method, resulting in films with a high percentage of aligned nanotubes. Photoelectrochemical characterization of 1/SWCNT thin films on indium-tin oxide showed the benefits of SWCNT alignment for photoconversion efficiency.

13.
J Nanosci Nanotechnol ; 14(9): 6732-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924324

RESUMO

The synthetic conjugated poly(1,4-arylene-2,5-thienylene) containing benzo[c][2,1,3]thiadiazole monomeric units (Bz-PAT) is proposed as active layer for the selective detection of mercuric ions. The Bz-PAT polymer chemical structure induces the formation of a disordered film with numerous vacancies and the size of these defects could be exploited for a reversible trapping of mercuric ions. For these reasons the Langmuir-Schaefer (LS) deposition method has been employed for transferring Bz-PAT layers with the desired accurate bi-dimensional organization control of the layer and with a high control of the deposition parameters. In this contribution, the frequency variation of quartz crystal microbalances functionalized with 10, 20, 30 and 40 LS runs of Bz-PAT have been investigated in response to the injection of aqueous solutions of HgCl2, Pb(NO3)2, NiCl2, CdCl2 and ZnSO4 at different concentrations (0.5 mM, 1 mM, 5 mM). An almost linear dependence on the number of the LS layers and hence on the film thickness, measured by means of ellipsometric spectroscopy, has been found in terms of sensor response to concentration of Hg2+ ions fluxed. By means of UV-Vis spectroscopy, the variations in the π-π* absorption band of the polymer, attributed to the thiophene segment, induced by HgCl2 injection has been analyzed and explained as a consequence of the electron transfer from the mercuric ion to the polymer solid film. These results, together with the linear relation found between the number of deposited layers and LS film thickness, suggest that the sensing mechanism can be explained both by an electron interaction between active layer and analyte and a diffusion mechanism of Hg2+ into the solid film that reaches an asymptotic value at 30 runs (about 80 nm), then a higher number of layers does not influence the sensor sensibility.


Assuntos
Íons/química , Mercúrio/química , Polímeros/química , Técnicas de Microbalança de Cristal de Quartzo/métodos , Análise Espectral/métodos , Íons/análise , Mercúrio/análise
14.
Chemistry ; 15(1): 136-48, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19021161

RESUMO

The synthesis and photophysical and electrochemical characterisation of new heteroleptic iridium complexes with electron-withdrawing sulfonyl groups and fluorine atoms bound to phenylpyridine ligands are reported. The emission energy of these materials strongly depends on the position of the sulfonyl groups and on the number of fluorine substituents. A 90 nm wide tuning range of photoluminescence from the blue-green (lambda(em)=468 nm) of iridium(III)bis[2-(4'-benzylsulfonyl)phenylpyridinato-N,C2'][3-(pentafluorophenyl)-pyridin-2-yl-1,2,4-triazolate] to the orange (lambda(em)=558 nm) of iridium(III)bis[2-(3'-benzylsulfonyl)phenylpyridinato-N,C2'](2,4-decanedionate) has been achieved. Emission quantum yields ranging from 47 to 71% have also been found for degassed solutions of the complexes, and a surprisingly high value of 16% was recorded for iridium(III)bis[2-(5'-benzylsulfonyl-3',6'-difluoro)phenylpyridinato-N,C2'](2,4-decanedionate) in air-equilibrated dichloromethane. A unusual stereochemistry of the benzylsulfonyl-substituted dimer and heteroleptic complexes has been detected by (1)H NMR spectroscopy, and is characterised by the mutual cis disposition of the pyridyl nitrogen atoms of the phenylpyridine ligands, which differs from the most common trans arrangement reported in the literature.

15.
Nat Mater ; 7(5): 412-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18425136

RESUMO

Organic thin-film transistor sensors have been recently attracting the attention of the plastic electronics community for their potential exploitation in novel sensing platforms. Specificity and sensitivity are however still open issues: in this respect chiral discrimination-being a scientific and technological achievement in itself--is indeed one of the most challenging sensor bench-tests. So far, conducting-polymer solid-state chiral detection has been carried out at part-per-thousand concentration levels. Here, a novel chiral bilayer organic thin-film transistor gas sensor--comprising an outermost layer with built-in enantioselective properties-is demonstrated to show field-effect amplified sensitivity that enables differential detection of optical isomers in the tens-of-parts-per-million concentration range. The ad-hoc-designed organic semiconductor endowed with chiral side groups, the bilayer structure and the thin-film transistor transducer provide a significant step forward in the development of a high-performance and versatile sensing platform compatible with flexible organic electronic technologies.

16.
J Org Chem ; 72(26): 10272-5, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-18044921

RESUMO

Oligoarylenes with three or four aromatic rings, bearing two S-acetylated mercaptomethyl groups in 1,3 position on one end of the polyaromatic system and presenting various functionalities on the other terminal ring, have been synthesized by the Suzuki-Miyaura cross-coupling reaction. The use of palladium complexes with a Buchwald's phosphine as ligand allowed us to perform this coupling reaction also in the presence of benzylic S-acetyl-protected functionalities on the aromatic halide. The obtained oligoarylenes are potential novel candidates for the generation of self-assembling monolayers on metal substrates.


Assuntos
Derivados de Benzeno/química , Hidrocarbonetos Clorados/química , Compostos de Sulfidrila/química , Compostos de Terfenil/síntese química , Ligantes , Estrutura Molecular , Estereoisomerismo
17.
Chem Commun (Camb) ; (1): 130-1, 2003 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-12611000

RESUMO

A series of poly(aryleneethynylene)s functionalized with acetylated glucopyranosyl units were synthesized by the Pd-catalyzed reaction of trimethylsilylethynyl derivatives with aromatic halides in the presence of silver oxide.

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