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1.
J Med Virol ; 96(5): e29621, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38654686

RESUMO

Mpox is a zoonotic disease historically reported in Africa. Since 2003, limited outbreaks have occurred outside Africa. In 2022, the global spread of cases with sustained interhuman transmission and unusual disease features raised public health concerns. We explore the mpox outbreak in Rio de Janeiro (RJ) state, Brazil, in an observational study of mpox-suspected cases from June to December 2022. Data collection relied on a public healthcare notification form. Diagnosis was determined by MPXV-PCR. In 46 confirmed cases, anti-OPXV IgG was determined by ELISA, and seven MPXV genomes were sequenced. A total of 3095 cases were included, 816 (26.3%) with positive MPXV-PCR results. Most positive cases were men in their 30 s and MSM. A total of 285 (34.9%) MPXV-PCR+ patients live with HIV. Eight were coinfected with varicella-zoster virus. Anogenital lesions and adenomegaly were associated with the diagnosis of mpox. Females and individuals under 18 represented 9.4% and 5.4% of all confirmed cases, respectively, showing higher PCR cycle threshold (Ct) values and fewer anogenital lesions compared to adult men. Anti-OPXV IgG was detected in 29/46 (63.0%) patients. All analyzed sequences belonged to clade IIb. In RJ state, mpox presented a diverse clinical picture, represented mainly by mild cases with low complication rates and prominent genital involvement. The incidence in females and children was higher than usually reported. The observation of a bimodal distribution of Ct values, with few positive results, may suggest the need to review the diagnostic criteria in these groups.


Assuntos
Surtos de Doenças , Humanos , Brasil/epidemiologia , Masculino , Feminino , Adulto , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Animais , Zoonoses/epidemiologia , Zoonoses/virologia , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/isolamento & purificação , Criança , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Anticorpos Antivirais/sangue , Idoso , Imunoglobulina G/sangue
2.
J Comput Chem ; 44(24): 1956-1969, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37306361

RESUMO

A new genetic algorithm has been proposed focusing on direct ab initio potential energy surface (PES) global minima search. Besides the commonly used operators, this new approach uses an operator to: improve the initial cluster generation, classify and compare all generated clusters, and use machine learning to model the quantum PES used in parallel optimization. Part of the validation process for this methodology was done with C u n A u m ( n + m ≤ X for X = 14 , 19 , 38 , 55 ) and A u n A g n ( n = 10 , 20 , 30 , 40 , 50 , 60 , 70 , and 75). The results are in fair agreement with the literature and led to a new global minimum for C u 12 A u 7 . A search has been done for the lowest energies of L i n nanoclusters with 2-8 atoms using the DFT approach and for L i 3 , L i 4 , L i 2 H , L i 3 H using DLPNO-CCSD(T) approach. NQGA successfully performed the MP2 optimizations for ( H 2 O ) 11 cluster. In all cases, the proposed genetic algorithm located the previously reported global minima with very efficient performance. The new proposed methodology makes it possible to optimize cluster geometries directly using high-level ab initio methods relinquishing any bias introduced by a classical approach. Our results show that this proposed method has great potential applications due to its flexibility and efficiency in identifying global minima in the tested atomic systems.

3.
J Paediatr Child Health ; 57(1): 121-125, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32932552

RESUMO

AIM: Although a correlation has been reported between enlarged rectal diameter and functional constipation (FC), the relevance of measuring the transverse diameter of the rectum for diagnosing FC remains unclear, even in patients with lower urinary tract symptoms (LUTS). This study aimed to measure rectal diameter in children/adolescents diagnosed with LUTS, with and without FC. METHODS: This cross-sectional study included 4-17 years old children/adolescents attending a multidisciplinary outpatient clinic for urinary disorders between June 2016 and November 2018. All participants had LUTS, with or without FC. Those incorrectly completing the study questionnaires or with neurological and/or anatomical abnormalities of the genitourinary and/or gastrointestinal tract were excluded. Urinary symptoms were evaluated using the dysfunctional voiding symptom score and FC was assessed using the Rome IV criteria. Transabdominal ultrasonography was used to evaluate the bladder and measure rectal diameter. A transverse diameter ≥3 cm defined an enlarged rectum. Bladder capacity (i.e. the bladder volume immediately before voiding), post-void residual urine, bladder wall thickness and first volume voided after ultrasonography were measured. RESULTS: Mean age was 8.9 ± 3.2 years and 55.1% were female. Of 107 patients included, constipation was diagnosed in 72 (67.3%), and lower urinary tract dysfunction in 90 (84.1%). In 72 participants (67.3%), lower urinary tract dysfunction was associated with FC, constituting bladder and bowel dysfunction. Rectal diameter was increased in 51 patients (47.7%). There was no association between rectal diameter ≥ 3 cm and urinary urgency, enuresis, increased daytime urinary frequency, nocturia, daytime incontinence, constipation, severe LUTS or bladder and bowel dysfunction (P > 0.05 in all cases). However, increased rectal diameter was associated with at least one episode of faecal incontinence per week in constipated patients (P = 0.02). There was no correlation between rectal diameter and dysfunctional voiding symptom score (rs = 0.00), bladder capacity (rs = 0.01), post-void residual urine (rs = 0.05), bladder wall thickness (rs = 0.00) or first volume voided after ultrasonography (rs = 0.06); P > 0.05 in all cases. CONCLUSION: There was no association between the current cut-off point characterising the rectum as distended and the severity of urinary symptoms, even when FC was present. However, the complaint of faecal incontinence associated with increased rectal diameter may suggest functional constipation. The cross-sectional design, however, constitutes a limitation. Further studies may be able to determine the ideal diagnostic cut-off point for bowel and urinary dysfunction. Rectal diameter was not associated with the intensity of LUTS, with or without FC. However, the complaint of faecal incontinence associated with increased rectal diameter may suggest functional constipation.


Assuntos
Sintomas do Trato Urinário Inferior , Reto , Adolescente , Criança , Pré-Escolar , Constipação Intestinal , Estudos Transversais , Feminino , Humanos , Masculino , Reto/diagnóstico por imagem , Micção
4.
J Mol Model ; 26(11): 317, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33098445

RESUMO

Alloy clusters of NaxLiy (4 ≤ x + y ≤ 10) are studied by exploring the potential energy surface in the ab initio MP2 level with the support of a quantum genetic algorithm (QGA). In some cases, the structures have been also refined with DFT and coupled-cluster methods. The general trends of sodium-lithium structures are in line with previous studies. The ionization potentials and polarizabilities to all structures were calculated with MP2 method and the average error between these two properties compared with experimental data was 6% and 13%, respectively. The topological analysis based on quantum theory of atoms in molecules (QTAIM) showed that by increasing the cluster size of the diatomic system there was a decrease of atomic interaction energies. The degree of degeneracy from D3BIA aromaticity index and the analysis of the atomic charges showed the influence (by charge transfer) of the chemical element in lower quantity in the cluster with respect to the other atoms. Our achievements of comparing our theoretical results with available experimental data have demonstrated that our approach can also predict satisfactorily quantum atomic and alloy clusters properties, at least, for low nuclearities.


Assuntos
Algoritmos , Elétrons , Lítio/química , Modelos Moleculares , Teoria Quântica , Sódio/química , Simulação por Computador , Termodinâmica
5.
Int J Infect Dis ; 93: 277-283, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081776

RESUMO

BACKGROUND: The present study evaluated factors associated with losses in the latent tuberculosis infection (LTBI) cascade of care in contacts of tuberculosis (TB) patients, in a referral center from a highly endemic region in Brazil. METHODS: Contacts of 1672 TB patients were retrospectively studied between 2009 and 2014. Data on TB screening by clinical investigation, radiographic examination and tuberculin skin test (TST) were extracted from medical records. Losses in the cascade of care and TB incidence within 2-year follow-up were calculated. RESULTS: From a total of 1180 TB contacts initially identified, only 495 were examined (58% loss), and 20 were diagnosed with active TB at this stage. Furthermore, 435 persons returned for TST result interpretation and 351 (∼81%) were TST positive. Among those with positive TST, 249 (73%) were treated with isoniazid for 6 months whereas 51 abandoned therapy early. Three individuals who did not receive LTBI treatment, one with incomplete treatment and another who completed treatment developed active TB. A logistic regression analysis revealed that increases in age were associated with losses in the LTBI cascade independent of other clinical and epidemiological characteristics. CONCLUSIONS: Major losses occur at initial stages and older patients are at higher risk of not completing the LTBI cascade of care.


Assuntos
Atenção à Saúde , Tuberculose Latente/terapia , Adulto , Fatores Etários , Antituberculosos/uso terapêutico , Brasil , Estudos de Coortes , Busca de Comunicante , Feminino , Humanos , Incidência , Isoniazida/uso terapêutico , Tuberculose Latente/diagnóstico , Tuberculose Latente/epidemiologia , Tuberculose Latente/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Teste Tuberculínico
6.
ACS Omega ; 5(6): 3030-3042, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32095726

RESUMO

Coordination compounds formed by flavonoid ligands are recognized as promising candidates as novel drugs with enhanced antioxidant and anticancer activity. Zn(II)-Rutin complexes have been described in the literature and distinct coordination modes proposed based on 1H NMR/MS and IR/UV-VIS experimental spectroscopic data: 1:1/1:2 (Zn(II) binding to A-C rings) and 2:1 (Zn(II) binding to A-C-B rings) stoichiometry. Aiming to clarify these experimental findings and provide some physical insights into the process of complex formation in solution, we carried out density functional theory calculations of NMR and UV-VIS spectra for 25 plausible Zn(II)-Rutin molecular structures including solvent effect using the polarizable continuum model approach. The studied complexes in this work have 1:1, 1:2, 2:1, and 3:1 metal-ligand stoichiometry for all relevant Zn(II)-Rutin configurations. The least deviation between theoretical and experimental spectroscopic data was used as an initial criterion to select the probable candidate structures. Our theoretical spectroscopic results strongly indicate that the experimentally suggested modes of coordination (1:2 and 2:1) are likely to exist in solution, supporting the two distinct experimental findings in DMSO and methanol solution, which may be seen as an interesting result. Our predicted 1:2 and 2:1 metal complexes are in agreement with the experimental stoichiometry; however, they differ from the proposed structure. Besides the prediction of the coordination site and molecular structure in solution, an important contribution of this work is the determination of the OH-C5 deprotonation state of rutin due to metal complexation at the experimental conditions (pH = 6.7 and 7.20). We found that, in the two independent synthesis of metal complexes, distinct forms of rutin (OH-C5 and O(-)-C5) are present, which are rather difficult to be assessed experimentally.

7.
RSC Adv ; 11(1): 599-611, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35423010

RESUMO

Prediction of NMR chemical shifts can assist experimentalists in the characterization of drug delivery systems based on carbon nanocomposites. Chemical shifts are strongly correlated to the nucleus position and its chemical neighborhood. Therefore, to predict structures and NMR properties of complex chemical models, choosing a more consistent theoretical level capable of providing more realistic results and moderate computational demand is a major challenge. In this work, we predicted the NMR spectra of inclusion compounds formed by cisplatin (cDDP) and an oxidized carbon nanotube (CNTox) and nanocone (CNCox) considered by specialists as potential drug delivery systems. The 195Pt NMR chemical shifts calculated at the DFT level with the new relativistic NMR-DKH basis set were -2314 ppm and -2192 ppm for cDDP@CNTox and cDDP@CNCox complexes, respectively, which are both high-field shifted relative to the free cDDP (-2110 ppm). 1H NMR chemical shifts are also sensitive to the inclusion process. The H (NH3) signals are found on average at +4.3 (cDDP), -5.1 (cDDP@CNTox) and +6.6 ppm (cDDP@CNCox). Interestingly, despite the similar inclusion modes in CNTox and CNCox cavities, the 1H NMR shifts were in opposite directions. A possible reason might be the higher stability of cDDP@CNTox (ΔE F = -19.9 kcal mol-1) than that of cDDP@CNCox (ΔE F = -5.7 kcal mol-1), which suggests a short guest-host contact in the former and consequently, a more efficient shielding of hydrogen atoms due to the electron-rich carbon structure. These results may be helpful as comparison data in the NMR spectra assignment in solution and the inclusion compounds' structural elucidation.

8.
J Chem Inf Model ; 60(2): 500-512, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-31738559

RESUMO

Carbon nanohorns (CNH) have been considered potential anticancer drug carriers, such as the cisplatin drug (cddp), due to their low toxicity, high purity, drug-loading capacity, and biodegradation routes. However, when it comes to nanomedicine applications, chemical functionalization is an essential step in order to overcome undesirable properties of these nanomaterials, such as the high hydrophobicity, low reactivity, and low dispersibility in polar solvents. In this context, the present study involved the modeling of new CNH topologies based on chemical oxidation and reduction mechanisms and the investigation of the influence of these modified structures on the dynamics and stability of inclusion complexes with cddp. The results indicated that these functionalization strategies lead to the opening of nanowindows on the CNH surfaces, which would constitute the main route for drug release, as reported by experimentalists. Also, our results showed that the insertion of polar functional groups on the oxidized CNH (CNHox-N) contributed to an improvement of the cddp@CNHox-N biocompatibility due to the greater number of hydrogen bonds formed with the solvent. Despite the favorable formation of all complexes, the binding free energies pointed out that the oxidation process made the cddp@CNHox-N complexes slightly less stable than the ones with pristine and reduced CNH. Besides, the results suggest the possibility to tune the complex stability by controlling the oxidation degree, which could be explored by the experimentalists in order to design controlled drug delivery systems based on CNH nanocarriers.


Assuntos
Cisplatino/química , Portadores de Fármacos/química , Simulação de Dinâmica Molecular , Nanotubos de Carbono/química , Liberação Controlada de Fármacos , Ligação de Hidrogênio , Conformação Molecular , Oxirredução , Propriedades de Superfície , Termodinâmica
10.
J Mol Graph Model ; 89: 167-177, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30903984

RESUMO

The medication with Pt-based antitumor drug cisplatin has demonstrated effective results against cancer cells, despite the severe side effects due to the high toxicity associated with the low selectivity of these anticancer agents. An alternative to overcome or decrease the side effects is to use drug delivery systems, which can carry high doses of the anticancer drug and promote its slow and targeted release to the tumor sites. Herein, we used molecular dynamics to study prototypes of the complexes formed by the encapsulated cisplatin and carbon nanohorns (CNH), with the purpose to characterize its structures and dynamical behavior in aqueous solution, an important feature to assess the potentiality of using CNH as carrier systems. The results indicated the presence of up to 36 water molecules inside the empty CNH cavity, depending on the cone angle and the presence of the cisplatin. Some of these solvent molecules are expelled out to the bulk upon cisplatin inclusion, although more than 10 molecules remain even for the narrow structures. Moreover, the calculated binding free energy (ΔbG) pointed out that the inclusion complexes formation between CNH structures and up to two cisplatin molecules was thermodynamically favorable in aqueous media, which suggests the potentiality of these carbon nanostructures as drug carriers. For the most likely and narrow host structure the average ΔbG was -92.0 kcal mol-1 for inclusion of two cisplatin, with most of the complex stability coming from the van der Waals contribution.


Assuntos
Cisplatino/administração & dosagem , Portadores de Fármacos , Simulação de Dinâmica Molecular , Nanoestruturas/química , Algoritmos , Linhagem Celular Tumoral , Cisplatino/química , Portadores de Fármacos/química , Humanos , Estrutura Molecular , Soluções
11.
ChemistryOpen ; 7(11): 902-913, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30460171

RESUMO

As the knowledge of the predominant molecular structure of antioxidant and anticancer flavonoid rutin in solution is very important for understanding the mechanism of action, a quantum chemical investigation of plausible rutin structures including solvent effects is of relevance. In this work, DFT calculations were performed to find possible minimum energy structures for the rutin molecule. 1H NMR chemical shift DFT calculations were carried out in DMSO solution using the polarizable continuum model (PCM) to simulate the solvent effect. Analysis of the experimental and theoretical 1H NMR chemical shift profiles offers a powerful fingerprint criterion to determine the predominant molecular structure in solution. Therefore, our aim is to find the best match between experimental (in DMSO-d) and theoretical (PCM-DMSO) 1H NMR spectrum profiles. Among 34 optimized structures located on the potential energy surface, we found that structure 32, with a B-ring deviated 30° from a planar configuration (geometry usually assumed for polyphenols), showed an almost perfect agreement with experimental the 1H NMR pattern when compared to the corresponding fully optimized planar geometry. This structure is also predicted as the global minimum based on room-temperature Gibbs free energy calculations in solution and, therefore, should be experimentally observed. This is new and valuable structural information regarding structure-activity relationship studies, and such information is hard to obtain by experimentalists without the aid of the X-ray diffraction technique.

12.
J Inorg Biochem ; 178: 134-143, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29132040

RESUMO

The toxicity of inclusion compounds formed by carbon nanostructures depends on its functionalized surface, use of solvents, dosage and other properties. Molecular modeling has potentially contributed to the understanding of the chemical nature of the formation of these systems and allows advancement in studies of the mechanism of transport, release of drugs and their biological implications. This work reports a quantum chemical investigation of the inclusion complexes formation between oxidized carbon nanotube (CNTox)/nanocone (CNCox) structure and cisplatin molecule, using the density functional theory (DFT) with the B3LYP functional and 6-31G(d,p)/LanL2DZ standard basis sets. Our results indicate that the cDDP@CNTox (inclusion complex - cisplatin into oxidized carbon nanotube) and cDDP@CNCox (inclusion complex - cisplatin into oxidized carbon nanocone) systems form stable molecular complexes that can be used as drug delivery devices. Our theoretical simulation of molecular spectra (IR, Raman and 1H NMR) reveals substantial changes due to complex formation that can be easily experimentally observed.


Assuntos
Cisplatino/química , Nanoestruturas/química , Nanotubos de Carbono/química , Simulação por Computador , Oxirredução , Teoria Quântica , Termodinâmica
13.
J Phys Chem A ; 121(14): 2839-2846, 2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28328211

RESUMO

In this paper, density functional theory calculations of nuclear magnetic resonance (NMR) chemical shifts for l-quebrachitol isomer, previously studied in our group, are reported with the aim of investigating in more detail the water solvent effect on the prediction of 1H NMR spectra. In order to include explicit water molecules, 20 water-l-quebrachitol configurations obtained from Monte Carlo simulation were selected to perform geometry optimizations using the effective fragment potential method encompassing 60 water molecules around the solute. The solvated solute optimized geometries were then used in B3LYP/6-311+G(2d,p) NMR calculations with PCM-water. The inclusion of explicit solvent in the B3LYP NMR calculations resulted in large changes in the 1H NMR profiles. We found a remarkable improvement in the agreement with experimental NMR profiles when the explicit hydrated l-quebrachitol structure is used in B3LYP 1H NMR calculations, yielding a mean absolute error (MAE) of only 0.07 ppm, much lower than reported previously for the gas phase optimized structure (MAE = 0.11 ppm). In addition, a very improved match between theoretical and experimental 1H NMR spectrum measured in D2O was achieved with the new hydrated optimized l-quebrachitol structure, showing that a fine-tuning of the theoretical NMR spectra can be accomplished once solvent effects are properly considered.

14.
Phys Rev Lett ; 118(5): 050401, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211725

RESUMO

We investigate the dynamics of Gaussian states of continuous variable systems under Gaussianity-preserving channels. We introduce a hierarchy of such evolutions encompassing Markovian and weakly and strongly non-Markovian processes and provide simple criteria to distinguish between the classes, based on the degree of positivity of intermediate Gaussian maps. We present an intuitive classification of all one-mode Gaussian channels according to their non-Markovianity degree and show that weak non-Markovianity has an operational significance, as it leads to a temporary phase-insensitive amplification of Gaussian inputs beyond the fundamental quantum limit. Explicit examples and applications are discussed.

15.
Carbohydr Polym ; 144: 400-9, 2016 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-27083832

RESUMO

Fucogalactomannan (FGM) is a non-sulphated polysaccharide isolated from the Tylopilus ballouii mushroom. We investigated the chemical characteristics of this FGM using HPLC, chemical methods, and NMR studies ((1)H, (13)C, (1)H/(13)C-HSQC and DEPT-135 spectroscopies) without chemical fragmentation. This polysaccharide consisted primarily of mannose and galactose with variable amounts of fucose and traces of xylose and with MW of 140kDa. Infrared and NMR spectroscopies showed the possible interaction between these polysaccharides and proteins. The antioxidant activity showed for FGM a high inhibition of superoxide and hydroxyl radicals with an IC50 of 1.25 and 1.6mg/mL, respectively. The results of peroxidation tests showed that FGM had an IC50 of 1.72mg/mL. Furthermore, the anti-inflammatory assay showed that FGM reduced edema by 32.8%, 42.0%, and 56% at doses of 30, 50, and 70mg/kg, respectively. Thus, these results suggested a structure and indicated possible anti-inflammatory and antioxidant activities use of these polysaccharides.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Basidiomycota/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/uso terapêutico , Antioxidantes/isolamento & purificação , Antioxidantes/uso terapêutico , Edema/tratamento farmacológico , Edema/patologia , Camundongos , Peso Molecular , Monossacarídeos/análise , Polissacarídeos/isolamento & purificação , Polissacarídeos/uso terapêutico
16.
J Inorg Biochem ; 129: 71-83, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24091348

RESUMO

This paper reports a quantum chemical investigation of the inclusion complex formation between a carbon nanohorn structure and cisplatin molecule, using the density functional theory (DFT) with the B3LYP functional and 6-31G(d,p)/LanL2DZ standard basis sets. The inclusion of the drug in host molecules such as carbon nanohorns (CNHs), aims to reduce the toxicity and enhance the effectiveness of cisplatin. In this work we carried out a search for minimum energy structures on the potential energy surface (PES) for CNH-cisplatin interaction, and then calculated the stabilization energy, charge distribution and NMR spectra, which can be of great aid for the experimental identification of the inclusion compound. Our results indicate that the CNH and cisplatin can indeed form stable inclusion complex, with the calculated (1)H NMR and (15)N NMR chemical shifts for cisplatin atoms revealing very substantial changes due to complex formation (~20ppm) that can be easily experimentally observed, which is helpful to the spectra assignment and the inclusion compound structural elucidation.


Assuntos
Cisplatino/química , Nanotubos de Carbono/química , Espectroscopia de Ressonância Magnética
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