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1.
Proc Natl Acad Sci U S A ; 121(32): e2400819121, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39074283

RESUMO

To test the hypothesis that an abiotic Earth and its inert atmosphere could form chemically reactive carbon- and nitrogen-containing compounds, we designed a plasma electrochemical setup to mimic lightning-induced electrochemistry under steady-state conditions of the early Earth. Air-gap electrochemical reactions at air-water-ground interfaces lead to remarkable yields, with up to 40 moles of carbon dioxide being reduced into carbon monoxide and formic acid, and 3 moles of gaseous nitrogen being fixed into nitrate, nitrite, and ammonium ions, per mole of transmitted electrons. Interfaces enable reactants (e.g., minerals) that may have been on land, in lakes, and in oceans to participate in radical and redox reactions, leading to higher yields compared to gas-phase-only reactions. Cloud-to-ground lightning strikes could have generated high concentrations of reactive molecules locally, establishing diverse feedstocks for early life to emerge and survive globally.

2.
Proc Natl Acad Sci U S A ; 120(25): e2220007120, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37307485

RESUMO

What constitutes a habitable planet is a frontier to be explored and requires pushing the boundaries of our terracentric viewpoint for what we deem to be a habitable environment. Despite Venus' 700 K surface temperature being too hot for any plausible solvent and most organic covalent chemistry, Venus' cloud-filled atmosphere layers at 48 to 60 km above the surface hold the main requirements for life: suitable temperatures for covalent bonds; an energy source (sunlight); and a liquid solvent. Yet, the Venus clouds are widely thought to be incapable of supporting life because the droplets are composed of concentrated liquid sulfuric acid-an aggressive solvent that is assumed to rapidly destroy most biochemicals of life on Earth. Recent work, however, demonstrates that a rich organic chemistry can evolve from simple precursor molecules seeded into concentrated sulfuric acid, a result that is corroborated by domain knowledge in industry that such chemistry leads to complex molecules, including aromatics. We aim to expand the set of molecules known to be stable in concentrated sulfuric acid. Here, we show that nucleic acid bases adenine, cytosine, guanine, thymine, and uracil, as well as 2,6-diaminopurine and the "core" nucleic acid bases purine and pyrimidine, are stable in sulfuric acid in the Venus cloud temperature and sulfuric acid concentration range, using UV spectroscopy and combinations of 1D and 2D 1H 13C 15N NMR spectroscopy. The stability of nucleic acid bases in concentrated sulfuric acid advances the idea that chemistry to support life may exist in the Venus cloud particle environment.


Assuntos
Bivalves , Vênus , Adenina , Agressão , Ácidos Sulfúricos
3.
Lasers Med Sci ; 38(1): 72, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790507

RESUMO

Functional chronic constipation (FCC) is a disorder caused by low fiber consumption, lack of fluid intake, lack of mobility, or side effects of medications. The objective of this study was to compare the effects of laser acupuncture and the commonly used osmotic laxative, lactulose (as the control), both combined with behavioral therapy and dietary modification, on children with FCC in a randomized controlled trial (RCT). Forty children were randomly chosen, aged 5-15 years with FCC, and randomized into two equal groups (gender ratio (50% male; 50% female), mean ± SD weight (24.2 ± 6.27 kg and 25.7 ± 7.47 kg for groups A and B, respectively)). Study group (group A): used laser acupuncture (650 nm), 30 mW, 0.15 cm2 spot size, 90 s per acupuncture point (ST25, ST36, ST37, BL25, and LI11). Control group (group B): lactulose syrup (1 to 3 mL/kg/day) orally, in divided doses 3 times weekly for 4 weeks, and behavioral training for both groups. Evaluations were conducted before and after the study to assess the efficacy of the therapy. Median value frequency significantly increased in groups A and B post-treatment (4 (6.75-3) and 3 (3.75-2), respectively) compared to pre-treatment (2 (2-1) and 2 (2-0.25), respectively) (p = 0.0001), in favor of group A (p = 0.01). Significant improvement of stool consistency according to Bristol stool scale (BSS) in groups A and B (p = 0.0001), (p = 0.002) respectively in favor of group A (p = 0.03). T-test, Fisher, and Wilcoxon signed rank tests were conducted to compare groups. Non-invasive, painless laser acupuncture therapy can be considered as an alternative therapy for patients with FCC.


Assuntos
Terapia por Acupuntura , Lactulose , Masculino , Feminino , Humanos , Criança , Lactulose/uso terapêutico , Constipação Intestinal/tratamento farmacológico , Pontos de Acupuntura , Lasers , Resultado do Tratamento
4.
Molecules ; 28(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36770815

RESUMO

The dramatic rise in cancer incidence, alongside treatment deficiencies, has elevated cancer to the second-leading cause of death globally. The increasing morbidity and mortality of this disease can be traced back to a number of causes, including treatment-related side effects, drug resistance, inadequate curative treatment and tumor relapse. Recently, anti-cancer bioactive peptides (ACPs) have emerged as a potential therapeutic choice within the pharmaceutical arsenal due to their high penetration, specificity and fewer side effects. In this contribution, we present a general overview of the literature concerning the conformational structures, modes of action and membrane interaction mechanisms of ACPs, as well as provide recent examples of their successful employment as targeting ligands in cancer treatment. The use of ACPs as a diagnostic tool is summarized, and their advantages in these applications are highlighted. This review expounds on the main approaches for peptide synthesis along with their reconstruction and modification needed to enhance their therapeutic effect. Computational approaches that could predict therapeutic efficacy and suggest ACP candidates for experimental studies are discussed. Future research prospects in this rapidly expanding area are also offered.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Peptídeos/química
5.
Molecules ; 28(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37513348

RESUMO

The potentiality of the ß12 borophene (ß12) and pristine graphene (GN) nanosheets to adsorb tetrahalomethanes (CX4; X = F, Cl, and Br) were investigated using density functional theory (DFT) methods. To provide a thorough understanding of the adsorption process, tetrel (XC-X3∙∙∙ß12/GN)- and halogen (X3C-X∙∙∙ß12/GN)-oriented configurations were characterized at various adsorption sites. According to the energetic manifestations, the adsorption process of the CX4∙∙∙ß12/GN complexes within the tetrel-oriented configuration led to more desirable negative adsorption energy (Eads) values than that within the halogen-oriented analogs. Numerically, Eads values of the CBr4∙∙∙Br1@ß12 and T@GN complexes within tetrel-/halogen-oriented configurations were -12.33/-8.91 and -10.03/-6.00 kcal/mol, respectively. Frontier molecular orbital (FMO) results exhibited changes in the EHOMO, ELUMO, and Egap values of the pure ß12 and GN nanosheets following the adsorption of CX4 molecules. Bader charge transfer findings outlined the electron-donating property for the CX4 molecules after adsorbing on the ß12 and GN nanosheets within the two modeled configurations, except the adsorbed CBr4 molecule on the GN sheet within the tetrel-oriented configuration. Following the adsorption process, new bands and peaks were observed in the band structure and density of state (DOS) plots, respectively, with a larger number in the case of the tetrel-oriented configuration than in the halogen-oriented one. According to the solvent effect affirmations, adsorption energies of the CX4∙∙∙ß12/GN complexes increased in the presence of a water medium. The results of this study will serve as a focal point for experimentalists to better comprehend the adsorption behavior of ß12 and GN nanosheets toward small toxic molecules.

6.
J Obstet Gynaecol ; 42(8): 3658-3665, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36519235

RESUMO

This was a randomised trial aimed to determine squatting exercises' effects on menstruation, pelvic mechanics, and uterine circulation in primary dysmenorrhoea. A total of 120 females with primary dysmenorrhoea were assigned into group (A), receiving yoga protocol, or groups (B, C & D), receiving yoga protocol added to modified wall squat, sumo squat, or deep squat, respectively. Menstrual pain and distress, pelvic inclination, and uterine circulation were measured before and after interventions using a pain scale, a questionnaire, palpation metre, and Doppler ultrasonography, respectively. There was a significant reduction in pain intensity in groups B & C (effect size = 3.97 & 5.89, respectively), compared to group A (effect size = 3.68), and in group C (effect size = 5.89) compared to group D (effect size = 3.94), pain subscale in the groups B, C & D (effect size = 1.69, 3.3 & 3.41, respectively), compared to group A (effect size= 2.47), water retention subscale in group D effect size 0.90 compared to group A (effect size =0.41) and in the questionnaire total scores in the groups C &D (effect size = 2.3 & 2.46, respectively) when compared to group A (effect size =1.94). Adding squatting exercises to yoga is more effective than yoga alone in reducing menstrual pain and distress.IMPACT STATEMENTWhat is already known on this subject? Physical exercises positively affect primary dysmenorrhoea in terms of decreased pain and distress, possibly through altering faulty posture. Squatting exercises affect lumbopelvic mechanics.What do the results of this study add? This study explores the effect of squatting exercises on pelvic inclination, menstrual aspects, and circulation.What are the implications of these findings for clinical practice and/or further research? Squatting exercises can be utilised to affect pelvic mechanics leading to decreased menstrual pain and distress, because of decreased pelvic congestion.


Assuntos
Dismenorreia , Menstruação , Útero , Yoga , Feminino , Humanos , Gravidez , Exercício Físico , Pelve , Circulação Placentária , Útero/irrigação sanguínea , Ultrassonografia Doppler , Estudos Prospectivos , Adulto
7.
J Obstet Gynaecol Res ; 47(12): 4210-4215, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34601765

RESUMO

AIM: We aimed to evaluate the addition of fetal thigh circumference (TC) to other ultrasound parameters to predict fetal weight compared to two standard formulae (Hadlock's and Vintzileos methods). METHODS: We conducted this prospective study on pregnant women between November 2018 and September 2019. The actual fetal weight was estimated within 48 h of delivery; then, it was compared to the estimated fetal weight by ultrasound. We used the Statistical Package for the Social Sciences (SPSS) software version 20.0 to perform the statistical analysis. RESULTS: A total of 123 pregnant women, with a mean age of 26.68 (5.24) years and a mean gestational age of 38.78 (0.85) weeks, were included in our study. We detected a significant positive correlation between different ultrasound parameters and actual weight (all p ≤ 0.001). The highest correlation was observed between TC and actual fetal weight (r = 0.685). Regarding both formulae, the correlation coefficient was higher in the Vintzileos formula than the Handlock formula (0.976 vs. 0.823). Our linear regression analysis showed that fetal TC could be an indicator for estimating fetal weight (p < 0.001). There was a statistically significant difference between the actual weight and the weight estimated by the Hadlock formula (p < 0.001). We detected no statistically significant difference between the estimated TC by ultrasound and the actual TC (p = 0.0602). CONCLUSION: Fetal TC can help accurately measure fetal birth weight when incorporated with other fetal parameters. The inclusion of fetal TC assessment in routine ultrasound examination is suggested to improve the birth estimates.


Assuntos
Peso Fetal , Coxa da Perna , Adulto , Peso ao Nascer , Feminino , Idade Gestacional , Humanos , Lactente , Gravidez , Estudos Prospectivos , Coxa da Perna/diagnóstico por imagem , Ultrassonografia Pré-Natal
8.
Inorg Chem ; 56(10): 6013-6026, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28452475

RESUMO

For the synthesis and selection of active platinum-based anticancer drugs that perform better than cisplatin and its analogues, six-coordinate octahedral Pt(IV) complexes appear to be promising candidates as, being kinetically more inert and more resistant to ligand substitution than four-coordinate Pt(II) centers, they are able to minimize unwanted side reactions with biomolecules prior to DNA binding. Due to their kinetic inertness, Pt(IV) complexes have also been exploited to bypass inconvenient intravenous administration. The most prominent example is satraplatin (Sat.) which is the first platinum antineoplastic agent reported to have oral activity. The present paper deals with a theoretical DFT investigation of the influence that the acidity of the biological environment can have on the activity of satraplatin and analogous octahedral Pt(IV) complexes having two carboxylates as axial ligands. Moreover, here the outcomes of a joint electrospray ionization mass spectrometry and DFT investigation of the fragmentation pathways of the protonated satraplatin are reported. Calculations show that the simulated acidic environment has an important impact on the satraplatin reactivity causing a significant lowering of the barrier that is necessary to overcome for the hydrolysis of the first acetate ligand to occur. Data from electrospray ionization mass spectrometry, 1H NMR, and potentiometric experiments strongly suggest that the loss of CH3COOH from the protonated satraplatin ion [Sat. + H]+ takes place almost immediately upon dissolution of satraplatin in methanol-water, D2O, and water solutions, respectively, at room temperature.


Assuntos
Antineoplásicos/química , Compostos Organoplatínicos/química , Teoria Quântica , Concentração de Íons de Hidrogênio , Hidrólise , Espectrometria de Massas , Potenciometria
9.
Cardiol Young ; 25(7): 1254-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25339059

RESUMO

BACKGROUND: We aimed to assess biatrial size and function, interactions on atrial and ventricular levels, and atrio-ventricular coupling in patients after tetralogy of Fallot repair. METHODS: A total of 34 patients with a mean age of 20.9±9 years, and 35 healthy controls, underwent two-dimensional speckle tracking echocardiography for ventricular and atrial strain measurements and real-time three-dimensional echocardiography to assess ventricular and atrial volumes. RESULTS: When compared with controls, tetralogy of Fallot patients had significantly reduced right atrial peak atrial longitudinal strain (p<0.01), right atrial peak atrial contraction strain (p<0.01), right atrial ejection fraction (p<0.01), left atrial peak atrial longitudinal strain (p<0.01), left atrial peak atrial contraction strain (p<0.05), and left atrial ejection fraction (p<0.01). In the tetralogy of Fallot group, left ventricular ejection fraction was negatively related to the right ventricular end-systolic volume normalised to body surface area (r=-0.62, p<0.01). An association was found in patients between the right atrial peak longitudinal strain and mean right ventricular strain (r=0.64, p<0.01). In patients, the left atrial peak longitudinal strain correlated negatively with right atrial end-diastolic volume normalised to body surface area (r=-0.67, p<0.01), whereas the left atrial ejection fraction correlated weakly with left ventricular ejection fraction (r=0.41, p<0.05). CONCLUSIONS: In asymptomatic tetralogy of Fallot patients, biatrial dysfunction exists and can be quantified via two-dimensional speckle tracking echocardiography as well as real-time three-dimensional echocardiography. Different forms of interactions on atrial and ventricular levels are evident among such cohorts.


Assuntos
Ecocardiografia Tridimensional/métodos , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
10.
Pediatr Cardiol ; 35(3): 530-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24196911

RESUMO

This study aimed to evaluate regional and global ventricular functions in the long term after aortic reimplantation of the anomalous left coronary artery from the pulmonary artery (ALCAPA) and to assess whether the time of surgical repair influences ventricular performance.The study examined 20 patients with a median age of 15 years (range 3-37 years) who had a corrected ALCAPA and 20 age-matched control subjects using echocardiography and tissue Doppler imaging (TDI). The median follow-up period after corrective surgery was 6 years (range 2.6-15 years). Seven patients underwent surgery before the age of 3 years (early-surgery group), whereas 13 patients had surgery after that age (late-surgery group). The TDI-derived myocardial strain of the interventricular septum (IVS), lateral wall of the left ventricle (LV), and lateral wall of the right ventricle (RV) in the basal and mid regions were examined, and a mean was calculated. The pulsed Doppler-derived Tei index was used to assess global left ventricular function. No significant differences were found between the early-surgery group and the control group regarding the regional myocardial strain or the Tei index. Compared with the early-surgery group, the late-surgery group had a significantly higher Tei index (mean 0.37; range 0.31-0.42 vs. mean 0.52; range 0.39-0.69; p < 0.005), a lower strain percentage of the lateral wall of the LV (mean 29; range 17-30 vs. mean 9; range 7-23), IVS (mean 23; range 21-31 vs. mean 19; range 13-25), and lateral wall of the RV (mean 23; range 21-31 vs. mean 19; range 13-25). The age at operation correlated significantly with the Tei index (r = 0.84, p < 0.001) and inversely with the mean strain of the lateral wall of the LV (r = -0.53, p = 0.028), IVS (r = -0.68, p = 0.003), and lateral wall of the RV (r = -0.68, p = 0.003). At the midterm follow-up evaluation after corrective surgery of ALCAPA, not only the left but also the right ventricular function seemed to be affected in patients with delayed diagnosis and late surgical repair but preserved among the younger patients with early diagnosis and corrective surgery.


Assuntos
Aorta Torácica/cirurgia , Anomalias dos Vasos Coronários/cirurgia , Artéria Pulmonar/cirurgia , Disfunção Ventricular Esquerda/etiologia , Adolescente , Adulto , Aorta Torácica/anormalidades , Aorta Torácica/diagnóstico por imagem , Criança , Pré-Escolar , Anomalias dos Vasos Coronários/diagnóstico por imagem , Ecocardiografia Doppler , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Artéria Pulmonar/anormalidades , Artéria Pulmonar/diagnóstico por imagem , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem
11.
Chem Pharm Bull (Tokyo) ; 62(4): 373-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24695347

RESUMO

A series of novel cyano oximino sulfonate derivatives were prepared from the reaction of arylsulfonyl chloride with different cyanoacetamide-based oximes ranging from the simplest unsubstituted amide to analogues containing N-ethyl (mimicking the Oxyma template), N-piperidinyl and N-morpholinyl chains. In addition, the cyano oximes, N-hydroxybenzimidoyl cyanide and N-hydroxypicolinimidoyl cyanide were also used in the synthesis of the novel cyano oximino sulfonate derivatives. The structures of the prepared compounds were confirmed by (1)H-NMR, (13)C-NMR, and elemental analysis. The preliminary bioassays showed that some of the title compounds, such as 2-oxo-2-(piperidin-1-yl)-N-(tosyloxy)acetimidoyl cyanide (TsPipOx), N-(tosyloxy)benzimidoyl cyanide (TsPhOX), N-(naphthalen-2-ylsulfonyloxy)-2-oxo-2-(piperidin-1-yl)acetimidoyl cyanide (NpsPipOx), 2-amino-N-(naphthalen-2-ylsulfonyloxy)-2-oxoacetimidoyl cyanide (NpsAmOx), N-(naphthalen-2-ylsulfonyloxy)benzimidoyl cyanide (NpsPhCN), and N-(naphthalen-2-ylsulfonyloxy)picolinimidoyl cyanide (NpsPyCN), showed anti-proliferation effect on the mouse fibroblast L929. The calculated IC50-values were ranging between 36.5 µg/mL and 0.235 mg/mL. However the anti-proliferation effects seem to be cytostatic rather than cytotoxic. The compounds only minimize the growth activity without completely killing the cells.


Assuntos
Alcanossulfonatos/síntese química , Citostáticos/química , Citostáticos/farmacologia , Alcanossulfonatos/farmacologia , Animais , Linhagem Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Citostáticos/síntese química , Fibroblastos/efeitos dos fármacos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade
12.
RSC Adv ; 14(31): 22408-22417, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39010916

RESUMO

Herein, the potential of ZO3 and ZF2 aerogen-comprising molecules (where Z = Ar, Kr, and Xe) to engage in σ-, lp-, and π-hole site-based interactions was comparatively studied using various ab initio computations. For the first time, a premier in-depth elucidation of the external electric field (EEF) influence on the strength of the σ-, lp-, and π-hole site-based interactions within the ZO3/ZF2⋯NH3 and ⋯NCH complexes was addressed using oriented EEF with disparate magnitude. Upon the energetic features, σ-hole site-based interactions were noticed with the most prominent preferability in comparison to lp- and π-hole analogs. This finding was ensured by the negative interaction energy values of -11.65, -3.50, and -2.74 kcal mol-1 in the case of σ-, lp-, and π-hole site-based interactions within the XeO3⋯ and XeF2⋯NH3 complexes, respectively. Detailedly, the strength of the σ- and lp-hole site-based interactions directly correlated with the atomic size of the aerogen atoms and the magnitude of the positively oriented EEF. Unexpectedly, an irregular correlation was noticed for the interaction energies of the π-hole site-based interactions with the size of the π-hole. Interestingly, the π-hole site-based interactions within Kr-comprising complexes exhibited higher negative interaction energies than the Ar- and Xe-comprising counterparts. Notwithstanding, a direct proportion between the interaction energies of the π-hole site-based interactions and π-hole size was obtained by employing EEF along the positive orientation with high strength. The present outcomes would be a fundamental basis for forthcoming progress in studying the σ-, lp-, and π-hole site-based interactions within aerogen-comprising complexes and their pertinent applications in materials science and crystal engineering.

13.
Asian Pac J Cancer Prev ; 25(6): 2113-2121, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38918674

RESUMO

OBJECTIVE: The lack of indicators to measure tumor's invasive biological behavior is an important issue. The aim of this study was to examine the effect of miRNAs 129 and 145 on tumor progression as well as patient survival. METHOD: Seventy five breast cancer (BC) patients and 75 controls were included in this research. Two miRNA expressions were estimated using real-time PCR. Biomarkers for BC detection was tested using ROC curves and AUC. RESULT: miR-129 and miR-145 expressions were significant. miR-129 and miR-145 classifiers (AUC = 0.943 and 0.748, respectively) help diagnose BC. Unlike miR-145, miR-129 did not affect the Kaplan-Meier survival curve analysis for progression-free survival at the end of the trial. The development of transitional cell carcinoma disease was found to have a strong correlation with miR-145 in both univariate and multivariate Cox regression analyses. Additionally, infiltrating + invasive urothelial carcinoma was also found to be correlated with miR-145. Conversely, elevated miR-129 expression in BC patients did not lead to an increase in cancer-specific recurrence or mortality, as observed in both univariate and multivariate Cox regression studies. CONCLUSION: The miRNA signature can help detect survival-associated miRNAs and develop BC miRNA therapeutics.


Assuntos
Biomarcadores Tumorais , MicroRNAs , Recidiva Local de Neoplasia , Neoplasias da Bexiga Urinária , Humanos , MicroRNAs/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/mortalidade , Feminino , Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estudos de Casos e Controles , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Idoso , Seguimentos , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/mortalidade , Masculino , Curva ROC
14.
ACS Omega ; 9(9): 10391-10399, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463322

RESUMO

σ-Hole site-based interactions in the trigonal bipyramidal geometrical structure of hypervalent pnicogen, halogen, and aerogen-bearing molecules with pyridine and NCH Lewis bases (LBs) were comparatively examined. In this respect, the ZF5···, XF3O2···, and AeF2O3···LB complexes (where Z = As, Sb; X = Br, I; Ae = Kr, Xe; and LB = pyridine and NCH) were investigated. The electrostatic potential (EP) analysis affirmations outlined the occurrence of σ-holes on the systems under consideration with disparate magnitudes that increased according to the following order: AeF2O3 < XF3O2 < ZF5. In line with EP outcomes, the proficiency of σ-hole site-based interactions increased as the atomic size of the central atom increased with a higher favorability for the pyridine-based complexes over NCH-based ones. The interaction energy showed the most favorable negative values of -35.97, -44.53, and -56.06 kcal/mol for the XeF2O3···, IF3O2···, and SbF5···pyridine complexes, respectively. The preferentiality pattern of the studied interactions could be explained as a consequence of (i) the dramatic rearrangement of ZF5 molecules from the trigonal bipyramid geometry to the square pyramidal one, (ii) the significant and tiny deformation energy in the case of the interaction of XF3O2 molecules with pyridine and NCH, respectively, and (iii) the absence of geometrical deformation within the AeF2O3···pyridine and ···NCH complexes other than the XeF2O3···pyridine one. Quantum theory of atoms in molecules and noncovalent interaction index findings reveal the partially covalent nature of most of the investigated interactions. Symmetry-adapted perturbation theory affirmations declared that the electrostatic component was the driving force beyond the occurrence of the considered interactions. The obtained findings will help in improving our understanding of the effect of geometrical deformation on intermolecular interactions.

15.
Life (Basel) ; 14(5)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38792560

RESUMO

We show that the nucleic acid bases adenine, cytosine, guanine, thymine, and uracil, as well as 2,6-diaminopurine, and the "core" nucleic acid bases purine and pyrimidine, are stable for more than one year in concentrated sulfuric acid at room temperature and at acid concentrations relevant for Venus clouds (81% w/w to 98% w/w acid, the rest water). This work builds on our initial stability studies and is the first ever to test the reactivity and structural integrity of organic molecules subjected to extended incubation in concentrated sulfuric acid. The one-year-long stability of nucleic acid bases supports the notion that the Venus cloud environment-composed of concentrated sulfuric acid-may be able to support complex organic chemicals for extended periods of time.

16.
Pediatr Cardiol ; 34(8): 1848-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23780551

RESUMO

To assess regional longitudinal systolic function of the right ventricle in patients with repaired tetralogy of Fallot (TOF) by tissue Doppler imaging-derived isovolumetric acceleration (IVA) index and determine the effect of right-ventricular (RV) enlargement on regional systolic function. In 30 consecutive TOF patients and 30 age-matched controls, myocardial velocity of the RV ventricular free wall in the basal and middle regions were examined in the apical four-chamber view. Peak myocardial velocity during IVA was recorded on the free RV wall. IVA index was calculated as the difference between baseline and peak velocity divided by their time interval. In 23 of the studied TOF patients, magnetic resonance imaging was performed on the same day to determine global RV volume and ejection fraction. IVA index of the RV lateral free wall was significantly lower in the basal (8.31 ± 6.00 vs. 19.00 ± 10.85 m/s(2), p = 0.0001) and middle segments (6.56 ± 5.22 vs. 16.17 ± 7.44 m/s(2), p = 0.0001) in patients than in controls. Among TOF patients, a negative correlation was found between IVA index in the middle segment and RV end-diastolic volume/body surface area (r = -0.549, p < 0.01). Similar to other longitudinal RV wall parameters, the IVA index showed a decreased value in the RV free wall, which is related to the impaired regional and global longitudinal RV systolic dysfunction. RV enlargement adversely affects regional longitudinal systolic function.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ventrículos do Coração/fisiopatologia , Contração Miocárdica/fisiologia , Tetralogia de Fallot/fisiopatologia , Função Ventricular Direita/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Ecocardiografia Doppler , Feminino , Seguimentos , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Sístole , Tetralogia de Fallot/diagnóstico , Tetralogia de Fallot/cirurgia , Adulto Jovem
17.
Heliyon ; 9(4): e15223, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37101647

RESUMO

The detection of pharmaceutical compounds in extremely low concentrations remains a challenge despite recent advancements in electrochemical sensing. In this study, a green hydrothermally synthesized nickel hydroxide-graphene hybrid material was used for the point-of-care determination of the antibiotic doxycycline (DOXY), which is a promising treatment for COVID-19 and other infections. The electrochemical sensor, based on a screen-printed electrode modified with the hybrid material, was able to detect DOXY in the range of 5.1 × 10-8 to 1.0 × 10-4 M, with a low detection limit of 9.6 × 10-9 M. This approach paves the way for eco-friendly and sustainable methods of nanomaterial synthesis for electrochemical analyses, particularly in point-of-care drug monitoring, and has the potential to improve access to testing platforms.

18.
Sci Rep ; 13(1): 11792, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37479792

RESUMO

An in-line smartphone connected to a screen-printed selective electrode hand-held device was used to determine the concentration of distigmine bromide (DB) in its pure and dosage forms as well as its degradation kinetics by continuously measuring the change in the produced emf over time. The main objective, supported by the data presented, is to produce a highly reliable smartphone integrated selective sensor as a portable analyzer with potential high cloud connectivity combining a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles. The choice of ionophore used in this approach was guided by computation and the data obtained was compared with traditional analytical techniques. DB, for which there are no previously reported stability-indicating methods and for which four novel such methods are proposed here, was selected as a model drug for this work. At-line UV-spectrophotometry DB assay was obtained by measuring the difference between the spectra of the degradation product and the same concentration of intact drug. The degradation kinetics were studied by this method through tracking the decrease of DB absorbance and/or the increase of a generated degradation product signal over time. Off-line separation based HPLC and TLC stability-indicating methods for DB were also presented. All methods employed in this work were validated for accuracy, precision, specificity, repeatability, linearity, range, detection and quantification limits according to the ICH guidelines and were applied to the analysis of laboratory prepared mixtures as well as commercial products. While all methods proposed were shown to be highly reliable, the smartphone integrated selective sensor is highlighted as a portable analyzer with potential high cloud connectivity and was shown to combine a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles.


Assuntos
Bioensaio , Química Analítica , Cinética , Eletrodos , Preparações Farmacêuticas
19.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37513931

RESUMO

Multidrug resistance (MDR) is one of the most problematic issues in chemotherapeutic carcinoma therapy. The ABCB1 transporter, a drug efflux pump overexpressed in cancer cells, has been thoroughly investigated for its association with MDR. Thus, discovering ABCB1 inhibitors can reverse the MDR in cancer cells. In the current work, a molecular docking technique was utilized for hunting the most prospective ABCB1 inhibitors from the Toxin and Toxin-Target Database (T3DB). Based on the docking computations, the most promising T3DB compounds complexed with the ABCB1 transporter were subjected to molecular dynamics (MD) simulations over 100 ns. Utilizing the MM-GBSA approach, the corresponding binding affinities were computed. Compared to ZQU (calc. -49.8 kcal/mol), Emamectin B1a (T3D1043), Emamectin B1b (T3D1044), Vincristine (T3D4016), Vinblastine (T3D4017), and Vindesine (T3D2479) complexed with ABCB1 transporter demonstrated outstanding binding affinities with ΔGbinding values of -93.0, -92.6, -93.8, -92.2, and -90.8 kcal/mol, respectively. The structural and energetic investigations confirmed the constancy of the identified T3DB compounds complexed with the ABCB1 transporter during the 100 ns MD course. To mimic the physiological conditions, MD simulations were conducted for those identified inhibitors complexed with ABCB1 transporter in the presence of a POPC membrane. These findings revealed that Emamectin B1a, Emamectin B1b, Vincristine, Vinblastine, and Vindesine are promising ABCB1 inhibitors that can reverse the MDR. Therefore, subjecting those compounds to further in-vitro and in-vivo investigations is worthwhile.

20.
Heliyon ; 9(8): e18690, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560653

RESUMO

Adsorption amplitude of the aluminum phosphide (Al12P12) nanocage toward the 2-Mercaptopyridine (MCP) drug was herein monitored based on density functional theory (DFT) calculations. The adsorption process through MCP⋅⋅⋅Al12P12 complex in various configurations was elucidated by means of adsorption (Eads) energies. According to the energetic affirmations, the Al12P12 nanocage demonstrated potential versatility toward adsorbing the MCP drug within the investigated configurations and exhibited significant negative adsorption energies up to -27.71 kcal/mol. Upon the results of SAPT analysis, the electrostatic forces showed the highest contributions to the overall adsorption process with energetic values up to -74.36 kcal/mol. Concurrently, variations of molecular orbitals distribution along with alterations in the energy gap (Egap) and Fermi level (EFL) of the studied nanocage were denoted after adsorbing the MCP drug. The favorable impact of water solvent within the MCP⋅⋅⋅Al12P12 complexes was unveiled and confirmed by negative solvation energy (ΔEsolv) values up to -17.75 kcal/mol. According to thermodynamic parameters, the spontaneous and exothermic natures of the considered adsorption process were proclaimed by negative values of ΔG and ΔH parameters. Significant changes in the IR and Raman peaks, along with the appearance of new peaks, were noticed, confirming the occurrence of the targeted adsorption process. Furthermore, the adsorption features of the MCP drug on the Al12N12 nanocage were elucidated and compared to the Al12P12 analog. The obtained results demonstrated the higher preferability of Al12P12 nanocage than the Al12N12 candidate towards adsorbing the MCP drug without structural distortion.

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