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1.
Pathogens ; 12(7)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513716

RESUMO

BACKGROUND AND AIMS: In Peru, the estimated prevalence of human immunodeficiency virus (HIV) and human T-lymphotropic virus-1 (HTLV-1) co-infection has been reported to be as high as 18%. Despite the endemicity of HTLV-1 in Peru, few studies have assessed the impact of HIV/HTLV-1 co-infection. Our study compared socio-demographic and clinical characteristics, and mortality rates between HIV-infected and HIV/HTLV-1 co-infected patients. METHODS: We reviewed the medical records of patients aged 18 years and older belonging to the HIV and HTLV-1 cohorts in Lima during a 30-year period: 1989-2019. Each HIV/HTLV-1 co-infected patient was randomly matched with two HIV-infected patients with similar characteristics (same sex, age ± 5 years, and same year of HIV diagnosis). Allegedly co-infected patients without a confirmatory diagnosis of HIV and HTLV-1 were excluded. Most of the patients in the HIV-infected group did not have a negative test result for HTLV-1 infection, so we used two probabilistic sensitivity analysis models to correct for potential HTLV-1 exposure misclassification bias in the group of HIV-infected patients. RESULTS: Of 162 patients enrolled, 54 were HIV/HTLV-1 co-infected and 108 were HIV-infected. The median age was 42 years (IQR = 34-51 years) and the majority were male (61.1%), single (44.4%), heterosexual (71%), born in Lima (58%), educated at the secondary school level (55.6%), and receiving antiretroviral treatment (91.4%). HIV/HTLV-1 co-infection was associated with an increased risk of death (HR: 11.8; 95% CI: 1.55-89.00; p = 0.017) while antiretroviral treatment was associated with a decreased risk of death (HR: 0.03; 95% CI: 0.003-0.25; p = 0.001). The overall mortality rate was 13.6 per 100 persons and the survival time for co-infected patients (median = 14.19 years) was significantly shorter than that of HIV-infected patients (median = 23.83 years) (p < 0.001). CONCLUSIONS: HIV/HTLV-1 co-infected patients had a significantly shorter survival time compared to HIV-infected patients, suggesting that the immune alterations caused by HTLV-1 in CD4 cell count may have contributed to late initiation of antiretroviral treatment and prophylaxis against opportunistic infections over the decades, and thus reducing their benefits in these patients.

2.
Antioxidants (Basel) ; 12(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36830043

RESUMO

The composition and structure of the interfacial region of emulsions frequently determine its functionality and practical applications. In this work, we have integrated theory and experiments to enable a detailed description of the location and orientation of antioxidants in the interfacial region of olive-oil-in-water nanoemulsions (O/W) loaded with the model gallic acid (GA) antioxidant. For the purpose, we determined the distribution of GA in the intact emulsions by employing the well-developed pseudophase kinetic model, as well as their oxidative stability. We also determined, by employing an in silico design, the radial distribution functions of GA to gain insights on its insertion depth and on its orientation in the interfacial region. Both theoretical and experimental methods provide comparable and complementary results, indicating that most GA is located in the interfacial region (~81.2%) with a small fraction in the aqueous (~18.82%). Thus, GA is an effective antioxidant to inhibit lipid oxidation in emulsions not only because of the energy required for its reaction with peroxyl radical is much lower than that between the peroxyl radical and the unsaturated lipid but also because its effective concentration in the interfacial region is much higher than the stoichiometric concentration. The results demonstrate that the hybrid approach of experiments and simulations constitutes a complementary and useful pathway to design new, tailored, functionalized emulsions to minimize lipid oxidation.

3.
Rev. med. hered ; 33(4)dic. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1424210

RESUMO

Objetivos: Determinar la validez de la evaluación de consumo de alcohol realizado en la Estrategia Nacional de Salud para la Prevención y Control de ITS-VIH / SIDA (ESNITSS) a pacientes con VIH que iniciaron tratamiento antirretroviral (TARV). Material y métodos: El tipo de estudio fue de evaluación de prueba diagnóstica en pacientes en TARV de un hospital del Ministerio de Salud (MINSA), entre septiembre de 2017 y enero de 2018; en base al análisis de datos de la Fase I del estudio "Efectividad de la Consejería en Enfermería en la Mejora de la Adherencia al TARV en pacientes con VIH y Conducta de Consumo de Alcohol". 4000 pacientes conformaron la población de estudio y 350 pacientes fueron seleccionados aleatoriamente. Se procedió a la validación de la evaluación del consumo de alcohol realizado por la ESNITSS con dos Gold estándar: i. la evaluación del consumo de alcohol en el último mes y ii. el consumo de riesgo identificado con el Alcohol Use Disorders Identification Test (AUDIT). Se calculó sensibilidad, especificidad, seguridad de la evaluación y razones de probabilidad. Resultados: La sensibilidad y especificidad fue regular para la evaluación de consumo de alcohol en el último mes (S=0,64, E=0,57), la especificidad fue mala para la evaluación de consumo de riesgo (E=0,48). Las razones de verosimilitud positivas demuestraron que la evaluación no tiene utilidad diagnóstica para ninguno de los casos (<2). Conclusiones: La evaluación de "consumo actual de alcohol" realizada por la ESNITSS no mostró utilidad diagnóstica.


SUMMARY Objectives: To determine the validity of the evaluation of alcohol consumption established by the national strategy to prevent and control STI-HIV-AIDS (ESNITSS) of HIV-infected adults that started anti-retroviral treatment (ART). Methods: Diagnostic study of HIV patients in a single hospital in Lima from September 2017 to January 2018 using data from a phase one study "Effectiveness of nursing counseling in improving adherence to ART among patient with alcohol consumption". Three hundred and fifty patients were randomly selected among 4000 participants. Two gold standards evaluated alcohol consumption: 1. Last month alcohol consumption and ii; alcohol consumption identified by the Alcohol Use Disorders Identification Test (AUDIT). Sensitivity, specificity, safety of the evaluation and probability rates. Results: sensitivity and specificity were moderate for last month alcohol consumption (s=0.64; e=0.57); specificity was low for evaluation of consumption risk (e=0.48). Positive validity rates demonstrated that the evaluation is not useful (<2). Conclusions: The evaluation of alcohol consumption followed by the ESNITSS has no diagnostic utility.

4.
PLoS One ; 16(8): e0256289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34411156

RESUMO

This study aims to describe knowledge on HIV and antiretroviral (ARV) treatment and psychosocial factors among people living with HIV (PLWH) in Lima, Perú, to explore characteristics associated to this knowledge, and determine its impact on sustained viral suppression. A cross-sectional survey was conducted among 171 PLWH at the largest referral health care center in Lima. The psychosocial factors measured were depression, risk of alcoholism, use of illegal drugs and disclosure. A participant had "poor knowledge" when less than 80% of replies were correct. Sustained viral suppression was defined as two consecutive viral loads under 50 copies/mL. A total of 49% and 43% had poor HIV and ARV knowledge respectively; 48% of the study population screened positive for depression and 27% reported feeling unsupported by the person they disclosed to. The largest gaps in HIV and ARV knowledge were among 98 (57%) that did not recognize that HIV increased the risk of cancer and among 57 (33%) participants that did not disagree with the statement that taking a double dose of ARV if they missed one. Moderate depression was significantly associated to poor HIV and ARV knowledge. Non-disclosure and being on ARVs for less than 6 months were associated with not achieving sustained viral suppression. Our findings highlight important HIV and ARV knowledge gaps of PLWH and a high burden of psychosocial problems, especially of depression, among PLWH in Lima, Peru. Increasing knowledge and addressing depression and disclosure could improve care of PLWH.


Assuntos
Depressão/epidemiologia , Infecções por HIV/epidemiologia , Carga Viral , Adolescente , Adulto , Antirretrovirais/uso terapêutico , Depressão/tratamento farmacológico , Depressão/etiologia , Depressão/psicologia , Revelação , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Adulto Jovem
5.
Int J STD AIDS ; 32(12): 1157-1164, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34156882

RESUMO

Due to a huge crisis extensive to health services many Venezuelan people living with HIV (PLWH) had migrated abroad, including Peru where favorable laws were in place until June 2019. We describe the health status and epidemiological trends of PLWH from Venezuela at an HIV program in Lima. We analyzed baseline and follow-up data of all Venezuelan PLWH enrolled in our HIV program from January 2017 to December 2019. A cross-sectional study in a subsample served to describe ARV adherence and context of migration. Between 2017-2019 our HIV Program registered 398 Venezuelan PLWH, representing 20% of the 2018 annual enrollments; numbers decreased since mid-2019. The median age was 30 years (IQR 26;37) and 90.5% were men. Between 2017 and 2019, the proportion with diagnosis in Peru increased from 14.3% to 60.9%; of AIDS stage at entry, from 8.8% to 27.2%. By December 2019, 182/250 (72.8%) were still in care, and 43 (10.8%) had not started ART. Viral suppression evaluated in 195, was achieved in 71.8%. From 2017 to 2019, migrant PLWH arrived in worsened clinical conditions, with increasing diagnosis in Peru; the flow of migrant PLWH entering care diminished with less favorable laws. Viral suppression rates were suboptimal.


Assuntos
Infecções por HIV , Migrantes , Adulto , Estudos Transversais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hospitais , Humanos , Masculino , Peru/epidemiologia
6.
Inorg Chem ; 59(19): 14101-14117, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32965111

RESUMO

The reaction of fac-[ReX(CH3CN)2(CO)3] (X = Cl, Br) with N-phenyl-[4-(dimethylamino)benzaldehyde] thiosemicarbazone (HLA) or N-4-methoxybenzyl-[4-(dimethylamino)benzaldehyde] thiosemicarbazone (HLB) under controlled synthetic conditions gave 4 mononuclear [ReX(HL)(CO)3] (X = Cl, Br) and 16 dinuclear [Re2L2(CO)6] compounds. These complexes were obtained as single crystals, and their structures were established by X-ray diffraction. The structural study of these dimers showed the formation of several solvates, the presence of linkage isomerism, and the stabilization of four- and/or five-membered chelate rings. The different ligand coordination modes (a new µ-κ2-S,N2:κ-N3 coordination mode for a thiosemicarbazone ligand was observed), the conformation of the thiosemicarbazone chain in each case, the formal symmetry of the dimers, and the role of the synthetic procedure in the stability of the different chelate rings were analyzed and are discussed. Theoretical calculations in the gas phase were performed for the dimers with the HLA ligand in order to identify the thermodynamically most stable species. The behavior and structural stability of dimers in dimethyl sulfoxide and acetone solutions was investigated by 1H NMR spectroscopy. The strength of the ReI-L bond in solution was evidenced by the formation of [Re2(LNO2)2(CO)6] and [Re(LA)(py)(CO)3] upon reaction of the corresponding dimer with concentrated nitric acid and pyridine, respectively.

7.
J Mol Model ; 19(12): 5293-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24154612

RESUMO

We have performed DFT and DFT-SAPT calculations on dimers of gallic acid, the model system for plant polyphenols, and the DNA base adenine. These dimers were selected for this study as they exhibit simultaneously hydrogen bonds and stacking interactions and it allows to quantify the relative values of these interactions. We calculate the relationships between the stability of the complexes, the charge transfer between monomers and the properties of the intermolecular bonds including hydrogen bonds and other bonds that do not involve hydrogen atoms. DFT-SAPT calculations were also performed to obtain the participation of the different types of energy and so the resulting physical effects. The results show that the presence of hydrogen bonds is the main stabilizing factor for dimers: the higher number and strength, the lower the dimer energy. The contribution of stacking to the stabilization is related to the strength and number of bonds between non-hydrogen atoms and quantified by the contribution of the dispersion terms to the interaction energy. Dimers I and II are mainly stabilized due to hydrogen bonds whereas dimer III is mainly stabilized by stacking interactions.


Assuntos
Adenina/química , DNA/química , Ácido Gálico/química , Dimerização , Ligação de Hidrogênio , Modelos Teóricos , Plantas/química , Polifenóis/química , Termodinâmica
8.
J Comput Chem ; 33(32): 2533-43, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22915376

RESUMO

A quantum theory of atoms in molecules-based energy partitioning was carried out for Z and E conformers of a series of O=C-X-R containing compounds. The results obtained for the simplest compound (formic acid) indicate that the attraction of the electron density within carbonyl oxygen by the nucleus of the acid hydrogen is the most important energy term for Z preference. This conclusion can be extended (mutatis mutandis) to larger carboxylic acids, esters, sulfur derivatives, secondary amides, and carbonyl isocyanates, and even explains the sequence of relative conformational energies in the HCXOH series (X = O, S, Se). In contrast, although the hyperconjugative model has been traditionally employed to explain this preference, we observe it is incompatible with: (i) relative values of diverse QTAIM atomic populations for the Z/E conformational equilibrium; (ii) conformational energies in the HCXOH series.


Assuntos
Amidas/química , Formiatos/química , Isocianatos/química , Teoria Quântica , Metilação , Conformação Molecular , Estereoisomerismo
9.
Chemistry ; 17(11): 3274-86, 2011 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21328496

RESUMO

Several measures of aromaticity including energetic, magnetic, and electron density criteria are employed to show how aromatic stabilization can explain the stability sequence of hydroporphyrins, ranging from porphin to octahydroporphin, and their preferred hydrogenation paths. The methods employed involve topological resonance energies and their circuit energy effects, bond resonance energies, multicenter delocalization indices, ring current maps, magnetic susceptibilities, and nuclear-independent chemical shifts. To compare the information obtained by the different methods, the results have been put in the same scale by using recently proposed approaches. It is found that all of them provide essentially the same information and lead to similar conclusions. Also, hydrogenation energies along different hydrogenation paths connecting porphin with octahydroporphin have been calculated with density functional theory. It is shown by using the methods mentioned above that the relative stability of different hydroporphyrin isomers and the observed inaccessibility of octahydroporphin both synthetically and in nature can be perfectly rationalized in terms of aromaticity.


Assuntos
Porfirinas/química , Hidrogenação , Modelos Moleculares , Teoria Quântica , Termodinâmica
10.
J Phys Chem A ; 113(11): 2652-7, 2009 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19235999

RESUMO

The applicability of the resonance model to explain the evolution of electron density was tested for a set of 15 nitriles whose protonation processes were studied by means of the quantum theory of atoms in molecules (QTAIM). The electron densities were obtained at the B3LYP/6-31++G**//B3LYP/6-31++G** and HF/6-31++G**//HF/6-31++G** levels. QTAIM atomic and bond properties do not follow the trends that should be expected according to the resonance model and our results are more in line with a H(+)-N[triple bond]C-R Lewis structure than with the H-N(+)[triple bond]C-R and H-N[triple bond]C(+)-R ones. Also, reasonable agreement between experimental and calculated PA values as well as good correlations between variations in atomic energies and populations as a result of protonation were found.

11.
J Chem Phys ; 129(16): 164114, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19045254

RESUMO

The partition of the multicenter electron delocalization indices and the nucleus independent chemical shift indices into alpha and beta contributions in open-shell systems has been performed. In general it is shown that a full understanding of aromaticity in these systems cannot be achieved by restricting the calculations to the global properties but by dissecting these properties into alpha and beta terms. The 4n+2- and 4n-aromaticity rules for singlet and triplet annulenes, respectively, reduce to a general aromaticity rule when the alpha and beta terms are studied separately. This new rule allows us to extend the concept of conflicting aromaticities to radical systems that are simultaneously alpha-aromatic and beta-antiaromatic or vice versa. The existence of such systems is demonstrated here by means of multicenter electron delocalization indices and nucleus independent chemical shifts. Finally, the global aromatic/antiaromatic character of these radical systems is estimated by means of aromatic stabilization energy, which is shown to be either slightly positive or slightly negative, thus reflecting the small aromatic/antiaromatic character of these radicals and reinforcing the conclusions obtained with aromaticity indices.

12.
J Comput Chem ; 28(2): 540-6, 2007 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-17186487

RESUMO

Ab initio complete optimizations at MP2/6-31++G** level have been performed in the T-shaped geometry of the benzene-benzene and benzene-naphthalene complexes. To check the effect of the basis set superposition error (BSSE), optimizations have been done in the BSSE corrected and BSSE uncorrected potential energy surfaces. The BSSE effect in the calculation of the Hessian has also been evaluated to check its influence in the frequency values. Quantum theory atoms in molecules (QTAIM) calculations have also been performed on both dimers. Intermolecular energies differ around a 25% when the optimization is performed with or without counterpoise corrected gradients. The influence of BSSE is also noticeable in the distances. Frequency shifts show big changes because of the BSSE. Thus, uncorrected values are up 350% larger than corrected ones. The hypotheses given in the literature to explain the origin of the blue-shifting hydrogen bond do not seem to give a suitable explanation for all characteristics of the behavior found in the studied systems.


Assuntos
Benzeno/química , Naftalenos/química , Teoria Quântica , Simulação por Computador , Ligação de Hidrogênio , Modelos Moleculares
13.
J Chem Phys ; 121(21): 10447-55, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15549925

RESUMO

Linear sulfur-carbon chains C(n)S (n=1-6) of astronomical interest were examined by means of several theoretical methods. The three smallest compounds of the series were chosen to evaluate the performance of several computational models, including Hartree-Fock theory, density functional theory with the Becke's three parameter exchange functional and the correlation functional of Lee, Yang, and Parr (B3LYP), and electron-correlated methods (second-order Moller-Plesset perturbation method (MP2), configuration interaction method including single and double excitations (CISD), and quadratic configuration interaction method including single and double excitations (QCISD) in combination with a large variety of basis sets. The systematic comparison between the experiment and theory indicates that the B3LYP/6-311G** method can be considered suitable for the study of the electronic structures of the C(n)S compounds. The electronic ground states of the C(n)S molecules alternate between 1Sigma and 3Sigma for odd and even values of n, respectively. The B3LYP/6-311G** wave functions for these electronic ground states were analyzed by means of the atoms in molecules (AIM) and natural bond orbital (NBO) methods. Both approaches suggest that the electronic structures for the singlet and triplet compounds must be considered separately. According to the NBO method, singlet compounds can be properly represented by acetylenic structures with alternating single and triple bonds (S[triple bond]C-C[triple bond]C...). However, triplet compounds are better described by means of double bond-double bond cumulenic structures (S=C=C=C=C...) as a consequence of the average between different alpha and beta electronic densities. AIM delocalization indexes and NBO interactions between localized orbitals also indicate that these structures are strongly pi delocalized. Finally, the different singlet and triplet structures proposed provide a consistent explanation for the geometries, dipole moments, and spin-density values of the C(n)S compounds studied.

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