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1.
AIDS Behav ; 28(8): 2547-2558, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38755430

RESUMO

Geosocial networking dating apps (GSN apps) are an increasingly widespread technology used by populations throughout the world to facilitate sexual encounters. Studies from a variety of settings suggest a possible association between GSN app use and HIV risk behaviors, including among sexual and gender minority populations such as men who have sex with men (MSM) and transgender women (TW). However, it remains unclear to what extent GSN apps play a causal role. We explored the relationship between GSN app use and sexual risk behaviors among MSM and TW in Lima, Peru by analyzing data from a multi-site cross-sectional survey assessing both general and partner-specific sexual behaviors. We performed bivariate analysis to estimate the association of GSN app use with different individual and partner-specific factors, then fit multivariable regression models adjusting for age and education. Among 741 total participants (698 MSM, 43 TW), 64% met at least one sex partner in the prior three months using a GSN app. GSN app users were significantly more likely to report engaging in HIV risk behaviors in general, including condomless receptive anal sex, group sex, transactional sex, and sex under the influence of alcohol or drugs. Having condomless anal sex with a given partner was not associated with meeting that partner via GSN app. These findings highlight GSN app users as a particularly vulnerable subpopulation among MSM and TW in Lima. GSN apps could provide a useful vehicle for targeted HIV prevention efforts for priority populations in Peru.


RESUMEN: Las aplicaciones de citas de redes geosociales (aplicaciones GSN) son una tecnología con creciente alcance en todo el mundo usadas para facilitar encuentros sexuales. Diferentes estudios sugieren una posible relación entre uso de aplicaciones GSN y comportamientos de riesgo para VIH entre hombres que tienen sexo con hombres (HSH) y mujeres transgénero (MT). No es claro hasta qué punto aplicaciones GSN tendrían un papel causal directo. Exploramos la relación entre uso de aplicaciones GSN y comportamientos sexuales de riesgo entre HSH y MT en Lima, Perú, analizando datos de una encuesta transversal que evaluó comportamientos sexuales en general y en parejas específicas. Realizamos análisis bivariable para estimar la asociación del uso de aplicaciones GSN con diferentes factores individuales y específicos de la pareja. También aplicamos modelos de regresión multivariables ajustados por edad y educación. Entre 741 participantes totales (698 HSH, 43 MT), 64% conoció al menos a una pareja sexual en los últimos tres meses mediante una aplicación GSN. Los usuarios de aplicaciones GSN fueron significativamente más propensos a reportar comportamientos de riesgo de VIH en general, incluyendo sexo anal receptivo sin condón, y sexo grupal, transaccional y bajo influencia de alcohol o drogas. Tener sexo anal sin condón con una pareja determinada no se asoció con conocer a esa pareja mediante aplicación GSN. Estos hallazgos muestran a usuarios de aplicaciones GSN como una subpoblación particularmente vulnerable entre HSH y MT en Lima. Aplicaciones GSN podrían ser útiles para iniciativas de prevención del VIH en poblaciones prioritarias en Perú.


Assuntos
Infecções por HIV , Homossexualidade Masculina , Aplicativos Móveis , Assunção de Riscos , Comportamento Sexual , Parceiros Sexuais , Pessoas Transgênero , Humanos , Masculino , Peru/epidemiologia , Estudos Transversais , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Pessoas Transgênero/psicologia , Pessoas Transgênero/estatística & dados numéricos , Adulto , Feminino , Homossexualidade Masculina/psicologia , Homossexualidade Masculina/estatística & dados numéricos , Comportamento Sexual/psicologia , Adulto Jovem , Rede Social , Adolescente , Pessoa de Meia-Idade , Inquéritos e Questionários , Minorias Sexuais e de Gênero/psicologia , Minorias Sexuais e de Gênero/estatística & dados numéricos
2.
Angew Chem Int Ed Engl ; 63(37): e202409524, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-38923738

RESUMO

A ruthenium-catalyzed reductive amination via asymmetric transfer hydrogenation (ATH) has been used to perform an efficient dynamic kinetic resolution (DKR) of N-aryl 2-formyl pyrroles decorated with a phosphine moiety positioned at the ortho' position. The strategy relies on the labilization of the stereogenic axis in the substrate facilitated by a transient Lewis acid-base interaction (LABI) between the carbonyl carbon and the phosphorus center. The reaction features broad substrate scope of aliphatic amines and N-aryl pyrrole scaffolds, and proceeds under very mild conditions to afford P,N atropisomers in good to high yields and excellent enantioselectivities (up to 99 % ee) for both diphenyl and dicyclohexylphosphino derivatives.

3.
J Org Chem ; 88(4): 2487-2492, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36704838

RESUMO

Modulable monosulfonyl squaramides have been shown to exert activation of gold(I) chloride complexes through H-bonding in an intermolecular way. Combinations of (PPh3)AuCl or IPrAuCl complexes and an optimal sulfonyl squaramide cocatalyst bearing two 3,5-bis(trifluoromethyl)phenyl groups efficiently catalyzed diverse heterocyclizations and a cyclopropanation reaction, avoiding in all cases undesired side reactions. Computational studies indicate that the Au-Cl bond breaks by transligation to the triple bond in a ternary complex formed by the actual AuCl···HBD catalyst and the substrate.

4.
J Adv Nurs ; 79(1): 372-384, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36300724

RESUMO

AIMS: To identify and synthesize evidence on the use of action research methods in mental health nursing care. DESIGN: Systematic review. DATA SOURCES: CINAHL, Web of Science, PubMed and Scopus databases were searched in January 2021. REVIEW METHODS: Data were selected using the updated Preferred Reporting Items for Systematic Reviews and Meta-Analysis framework. Two reviewers independently conducted the study selection, and quality appraisal using Joanna Briggs Institute Critical Appraisal Checklist for Qualitative Research, data extraction and data analysis procedures. RESULTS: Sixteen studies, half of which used participatory action research, were included in this review. Nurses, along with other stakeholders, were an active part of the action research process. The main topics of interest addressed were categorized as improving the adoption of a person-centred approach to care and improving decision-making procedures. The use of action research helped the participants to identify the meaning they attached to the topic of interest to be improved. Moreover, this method helped to identify needs and strategies for improving care. The studies concurred that the use of action research enabled participants to gain awareness, improve attitudes and acquire knowledge. In addition, it enabled participants to gain confidence and security in the group context, as key aspects of their empowerment. CONCLUSION: This review shows the usefulness of action research in any mental health nursing context, contributing to the improvement of care at both the individual and collective levels. IMPACT: This paper demonstrates the use of the action research method in the field of mental health nursing. Its use has improved the clinical practice of nurses as well as that of teams in both community and hospital settings, addressing issues of the person-centred approach to care and decision-making procedures.


Assuntos
Enfermagem Psiquiátrica , Humanos , Pesquisa Qualitativa , Pesquisa sobre Serviços de Saúde , Projetos de Pesquisa
5.
Angew Chem Int Ed Engl ; 62(35): e202306981, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37389578

RESUMO

An atroposelective Ir-catalyzed dynamic kinetic resolution (DKR) of 2-(quinolin-8-yl)benzaldehydes/1-naphthaldehydes by transfer hydrogenative coupling of allyl acetate is disclosed. The allylation reaction takes place with simultaneous installation of central and axial chirality, reaching high diastereoselectivities and excellent enantiomeric excesses when ortho-cyclometalated iridium-DM-BINAP is used as the catalyst. The racemization of the substrates occurs through a designed transient Lewis acid-base interaction between the quinoline nitrogen atom and the aldehyde carbonyl group.

6.
Chemistry ; 28(28): e202104442, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35191558

RESUMO

Molecules with restricted rotation around a single bond or atropisomers are found in a wide number of natural products and bioactive molecules as well as in chiral ligands for asymmetric catalysis and smart materials. Although most of these compounds are biaryls and heterobiaryls displaying a C-C stereogenic axis, there is a growing interest in less common and more challenging axially chiral C-N atropisomers. This review offers an overview of the various methodologies available for their asymmetric synthesis. A brief introduction is initially given to contextualize these axially chiral skeletons, including a historical background and examples of natural products containing axially chiral C-N axes. The preparation of different families of C-N based atropisomers is then presented from anilides to chiral five- and six-membered ring heterocycles. Special emphasis has been given to modern catalytic asymmetric strategies over the past decade for the synthesis of these chiral scaffolds. Applications of these methods to the preparation of natural products and biologically active molecules will be highlighted along the text.


Assuntos
Produtos Biológicos , Produtos Biológicos/química , Catálise , Ligantes , Estereoisomerismo
7.
Chem Soc Rev ; 50(5): 2968-2983, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33491680

RESUMO

This tutorial review provides a systematic overview of the available methodologies for the atroposelective transformation of (heterobiaryl)biaryl precursors toward the synthesis of enantiomerically enriched products and the conceptual aspects associated to each type of transformation. Depending on the presence or absence of symmetry in the starting material and the participation of racemization or dynamization events along the process, several strategies have been developed, including desymmetrization, classical kinetic resolution (KR), dynamic kinetic resolution (DKR) and dynamic kinetic asymmetric transformation (DYKAT). Seminal contributions and a handful of selected examples are discussed to illustrate the potential of these synthetic tools.

8.
Eur Respir J ; 58(2)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33446609

RESUMO

BACKGROUND: Around 8-10% of individuals over 50 years of age present interstitial lung abnormalities (ILAs), but their risk factors are uncertain. METHODS: From 817 individuals recruited in our lung ageing programme at the Mexican National Institute of Respiratory Diseases, 80 (9.7%) showed ILAs and were compared with 564 individuals of the same cohort with normal high-resolution computed tomography to evaluate demographic and functional differences, and with 80 individuals randomly selected from the same cohort for biomarkers. We evaluated MUC5B variant rs35705950, telomere length, and serum levels of matrix metalloproteinase (MMP)-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, MMP-13, interleukin (IL)-6, surfactant protein (SP)-D, α-Klotho and resistin. RESULTS: Individuals with ILAs were usually males (p<0.005), older than controls (p<0.0001), smokers (p=0.01), with a greater frequency of MUC5B rs35705950 (OR 3.5, 95% CI 1.3-9.4; p=0.01), and reduced diffusing capacity of the lung for carbon monoxide and oxygen saturation. Resistin, IL-6, SP-D, MMP-1, MMP-7 and MMP-13 were significantly increased in individuals with ILAs. Resistin (12±5 versus 9±4 ng·mL-1; p=0.0005) and MMP-13 (357±143 versus 298±116 pg·mL-1; p=0.004) were the most increased biomarkers. On follow-up (24±18 months), 18 individuals showed progression which was associated with gastro-oesophageal reflux disease (OR 4.1, 95% CI 1.2-12.9; p=0.02) and in females with diabetes mellitus (OR 5.3, 95% CI 1.0-27.4; p=0.01). CONCLUSIONS: Around 10% of respiratory asymptomatic individuals enrolled in our lung ageing programme show ILAs. Increased serum concentrations of pro-inflammatory molecules and MMPs are associated with ILAs.


Assuntos
Doenças Pulmonares Intersticiais , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Metaloproteinase 7 da Matriz , Mucina-5B , Fatores de Risco
9.
AIDS Behav ; 25(7): 2139-2153, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33411208

RESUMO

Sexual communication with partners informs risk assessment and sexual practices. We evaluated participant, partner, and network factors associated with communication about condom use and HIV serostatus and explored their relationships with condomless anal intercourse (CAI) among 446 men who have sex with men (MSM) and 122 transgender women (TW) in Lima, Peru. Generalized estimating equations assessed contextual influences on communication and practices with recent sexual partners. More frequent HIV communication was reported by MSM who: identified as heterosexual, compared to bisexual or gay; characterized partnerships as stable, compared to casual, anonymous, or commercial; or discussed HIV/STIs with close social contacts (p < 0.05). TW in concurrent partnerships discussed condom use more frequently than those in monogamous relationships (p < 0.05). Condom use discussions and alcohol use among MSM were associated with CAI (p < 0.05). Findings highlight complexity in sexual decision-making and call for further study of conversation content and practices to inform HIV prevention messaging.


RESUMEN: La comunicación sexual entre parejas informa sobre la valoración de riesgos y las prácticas sexuales. Evaluamos los factores de participantes, sus parejas y sus redes en relación con la comunicación sobre el uso de condones y el serostatus del VIH, y exploramos sus asociaciones con el sexo anal sin condón (CAI) entre 446 hombres que tienen sexo con hombres (HSH) y 122 mujeres transgéneros (MT) en Lima, Perú. Usamos ecuaciones de estimación generalizadas para evaluar las influencias contextuales en la comunicación y las prácticas con parejas sexuales recientes. La comunicación sobre el VIH fue más frecuente entre los HSH: que se identificaron como heterosexuales, en comparación con bisexuales o gay; quienes reportaron sus relaciones de pareja como estables, en comparación a casuales, anónimas o comerciales; o quienes discutieron el VIH/ITS con contactos sociales cercanos (p < 0.05). Las MT con relaciones concurrentes discutieron el uso de condones con más frecuencia que las que reportaron relaciones monógamas (p < 0.05). Las discusiones sobre el uso de condones y el consumo de alcohol se asociaron con CAI entre los HSH (p < 0.05). Estos resultados resaltan la complejidad de las decisiones sexuales y ameritan un mayor estudio del contenido y las prácticas de conversación para informar los mensajes de prevención del VIH.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Pessoas Transgênero , Comunicação , Preservativos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Peru/epidemiologia , Comportamento Sexual , Parceiros Sexuais , Sexo sem Proteção
10.
BMC Public Health ; 21(1): 1090, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34098916

RESUMO

BACKGROUND: Social networks, norms, and discussions about sexual health may inform sexual practices, influencing risk of human immunodeficiency virus (HIV) or sexually transmitted infection (STI) acquisition. To better understand social networks of Peruvian men who have sex with men (MSM) and transgender women (trans women), we examined key social network members (SNMs), participant perceptions of these network members' opinions toward sexual health behaviors, and associations between network member characteristics and condomless anal intercourse (CAI). METHODS: In a 2017 cross-sectional study, a convenience sample of 565 MSM and trans women with HIV-negative or unknown serostatus was asked to identify three close SNMs; describe discussions about HIV and STI prevention with each; and report perceived opinions of condom use, HIV/STI testing, and partner notification of STIs. Generalized estimating equations evaluated relationships between SNM characteristics, opinions, and discussions and participant-reported CAI. RESULTS: Among participants who identified as MSM, 42.3% of key SNMs were perceived to identify as gay. MSM "never" discussed HIV and STI prevention concerns with 42.4% of heterosexual SNMs, but discussed them "at least once weekly" with 16.9 and 16.6% of gay- and bisexual- identifying SNMs, respectively. Among participants who identified as trans women, 28.2% of key SNMs were perceived as heterosexual; 25.9%, as bisexual; 24.7%, as transgender; and 21.2%, as gay. Trans women discussed HIV/STI prevention least with cis-gender heterosexual network members (40.2% "never") and most with transgender network members (27.1% "at least once weekly"). Participants perceived most of their close social network to be completely in favor of condom use (71.2% MSM SNMs, 61.5% trans women SNMs) and HIV/STI testing (73.1% MSM SNMs, 75.6% trans women SNMs), but described less support for partner STI notification (33.4% MSM SNMs, 37.4% trans women SNMs). Most participants reported CAI with at least one of their past three sexual partners (77.5% MSM, 62.8% trans women). SNM characteristics were not significantly associated with participant-reported frequency of CAI. CONCLUSIONS: Findings compare social support, perceived social norms, and discussion patterns of Peruvian MSM and trans women, offering insight into social contexts and sexual behaviors. TRIAL REGISTRATION: The parent study from which this analysis was derived was registered at ClinicalTrials.gov (Identifier: NCT03010020 ) on January 4, 2017.


Assuntos
Infecções por HIV , Saúde Sexual , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Pessoas Transgênero , Comunicação , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Peru/epidemiologia , Comportamento Sexual , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Rede Social
11.
Molecules ; 26(2)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445529

RESUMO

Room temperature ionic liquids (RTILs) have been widely used as (co)solvents in several catalytic processes modifying, in most of the cases, the catalyst activity and/or the selectivity for the studied reactions. However, there are just a few examples of their use in hydrogen bonding organocatalysis. In this paper, we show the positive effect of a set of imidazole-based ionic liquids ([bmim]BF4 and [hmim]PF6) in the enantioselective addition of formaldehyde tert-butylhydrazone to prochiral α-keto esters catalyzed by a sugar-based chiral thiourea. Reactions performed in the presence of low percentages of RTILs led to an increase of the catalyst activity, thereby making possible to work at lower temperatures. Thus, the chiral tert-butyl azomethyl tertiary alcohols could be obtained with moderate to good conversions and higher enantioselectivities for most of the studied substrates when using up to 30 vol% of [hmim]PF6 as a cosolvent in processes performed in toluene.


Assuntos
Líquidos Iônicos/química , Temperatura , Catálise , Hidrazonas/química , Modelos Moleculares , Estereoisomerismo , Tioureia/química
12.
Angew Chem Int Ed Engl ; 60(10): 5096-5101, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33045143

RESUMO

A highly enantio- and diastereoselective thiourea-catalyzed dearomatization of isoquinolines employing N-tert-butylhydrazones as neutral α-azo carbanions and masked acyl anion equivalents has been developed. Experimental and computational data supports the generation of highly ordered complexes wherein the chloride behaves as a template for the catalyst, the hydrazone reagent, and the isoquinolinium cation, providing excellent stereocontrol in the formation of two contiguous stereogenic centers. The ensuing selective and high-yielding transformations provide appealing dihydroisoquinoline derivatives.

13.
J Am Chem Soc ; 142(37): 16082-16089, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32813511

RESUMO

The AuI-catalyzed reaction between terminal alkynes and aromatic haloalkynes proceeds through divergent pathways depending on the nature of the catalyst counteranion. Thus, cationic complexes containing strongly basic NHC ligands and noncoordinating anions such as BArF4 catalyze the cis haloalkynylation of the terminal alkyne, whereas introduction of a weakly basic triflate counteranion results in the stereoselective hydroalkynylation of the haloalkyne, yielding haloenyne products in good yields and complete trans selectivity. Experimental and computational studies suggest that the hydroalkynylation reaction takes place via nucleophilic attack of the terminal alkyne to the C2 carbon of the activated haloalkyne, assisted by a concerted proton abstraction by the triflate, and that the protodeauration is the turnover-limiting step, in agreement with an observed primary kinetic isotope effect.

14.
J Am Chem Soc ; 142(5): 2628-2639, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31923357

RESUMO

A highly regio-, diastereo-, and enantioselective, scalable Ir-catalyzed hydroarylation of electron-rich acyclic and tensioned cyclic olefins with heterobiaryls is described. The reaction of acyclic vinyl ethers, dihydrofuran, and norbornenes with a variety of aryl isoquinoline, quinazoline, and picoline derivatives takes place with simultaneous installation of central and axial chirality, reaching complete branched/linear or exo/endo ratios and excellent diastereo- and enantiomeric excesses when in situ formed [IrI/Tol-SDP] or [IrI/Tol-BINAP] complexes are used as the catalysts. Deuterium labeling experiments and a comprehensive computational study suggest that, despite fast double bond migratory insertion into Ir-H, the reaction proceeds through a modified Chalk-Harrod mechanism, starting with selectivity-determining insertion into Ir-CAryl. The regioselectivity is controlled by the electron-donating alkoxy group, whereas diastereo- and enantioselectivity have a complex origin, which depend on the relative orientation of the alkoxy group and the establishment of adequate π-π interactions between the biaryl and the phosphine.

15.
Chemistry ; 26(3): 629-633, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31702073

RESUMO

The formal insertion of alkenes into aromatic chloro- and bromoalkynes takes place under cationic gold catalysis. This haloalkynylation reaction can be performed with cyclic, gem-disubstituted and monosubstituted alkenes, using BINAP, triazolo[4,3-b]isoquinolin-3-ylidene ligands or SPhos, respectively. The products were isolated in moderate to excellent yields and with complete diastereo- and regioselectivity; the halogen atom bonding the more substituted carbon of the alkene. Preliminary experiments showed that the enantioselective haloalkynylation of cyclopentene can be performed with (S)-BINAP to afford the insertion products with moderate to good enantioselectivities.

16.
BMC Pulm Med ; 20(1): 164, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517728

RESUMO

BACKGROUND: Several lung structural and functional abnormalities may occur associated with aging, including emphysema. In this study, we evaluated the frequency and risk factors associated with emphysema in respiratory asymptomatic individuals enrolled in our Lung Aging Program. From a cohort of 687 subjects, we found by high-resolution computed tomography (HRCT) 29 individuals (4%) with emphysematous changes that were compared with 87 controls (3:1) randomly selected from the same cohort. METHODS: This was a transversal, observational, case-control study where we examined demographics and functional characteristics, as well as telomere length and serum Klotho concentration, two conditions that have been associated with aging and some aging-associated diseases including emphysema. RESULTS: Individuals with subclinical pulmonary emphysema were older (72 ± 9 versus 67 ± 6 years), and primarily smoker males with low body mass index. Despite that they were asymptomatic, two of them exhibited a decrease of forced expiratory volume in 1 s (FEV1), with a lower FEV1/FVC suggesting airway obstruction. Cigarette smoking (OR = 5.43, CI95% 1.8-16.7), family history of lung disease (OR = 4.32, CI95% 1.0-19.0) and lower body mass index (OR 7.22, CI95% 1.2-3.5) were risk factors for the development of lung emphysematous changes. No association was found with telomere length and Klotho serum concentration. CONCLUSION: Our findings reveal that a small but important percentage of older people without respiratory symptoms, present pulmonary emphysema and indicate that smoking exposure and genetic background may contribute to etiological factors.


Assuntos
Envelhecimento , Pulmão/fisiopatologia , Enfisema Pulmonar/diagnóstico , Enfisema Pulmonar/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Fumar Cigarros/efeitos adversos , Feminino , Glucuronidase/sangue , Humanos , Proteínas Klotho , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Enfisema Pulmonar/sangue , Testes de Função Respiratória , Fatores de Risco , Telômero/fisiologia , Tomografia Computadorizada por Raios X
17.
Int J Mol Sci ; 21(14)2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32650494

RESUMO

This report describes a functional and structural analysis of fused glucose-6-phosphate dehydrogenase dehydrogenase-phosphogluconolactonase protein from the protozoan Trichomonas vaginalis (T. vaginalis). The glucose-6-phosphate dehydrogenase (g6pd) gene from T. vaginalis was isolated by PCR and the sequence of the product showed that is fused with 6pgl gene. The fused Tvg6pd::6pgl gene was cloned and overexpressed in a heterologous system. The recombinant protein was purified by affinity chromatography, and the oligomeric state of the TvG6PD::6PGL protein was found as tetramer, with an optimal pH of 8.0. The kinetic parameters for the G6PD domain were determined using glucose-6-phosphate (G6P) and nicotinamide adenine dinucleotide phosphate (NADP+) as substrates. Biochemical assays as the effects of temperature, susceptibility to trypsin digestion, and analysis of hydrochloride of guanidine on protein stability in the presence or absence of NADP+ were performed. These results revealed that the protein becomes more stable in the presence of the NADP+. In addition, we determined the dissociation constant for the binding (Kd) of NADP+ in the protein and suggests the possible structural site in the fused TvG6PD::6PGL protein. Finally, computational modeling studies were performed to obtain an approximation of the structure of TvG6PD::6PGL. The generated model showed differences with the GlG6PD::6PGL protein (even more so with human G6PD) despite both being fused.


Assuntos
Hidrolases de Éster Carboxílico/genética , Estabilidade Enzimática/genética , Glucosefosfato Desidrogenase/genética , NADP/genética , Proteínas de Protozoários/genética , Proteínas Recombinantes/genética , Trichomonas vaginalis/genética , Sequência de Aminoácidos , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Estabilidade Proteica , Alinhamento de Sequência , Temperatura
18.
Rev Med Chil ; 148(2): 263-267, 2020 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-32730505

RESUMO

Patent foramen ovale (PFO) is a prevalent congenital septal atrial defect usually without pathological significance. In certain pathogenic situations, PFO can trigger episodes of recurrent hypoxemia, a specific condition known as platipnea-orthodeoxia syndrome (POS). We report a 73 years old female presenting with dyspnea and low arterial oxygen saturation. On admission the patient had a hemoglobin saturation of 81% and an arterial oxygen partial pressure of 50 mmHg. After breathing 100% a 17% arterial-venous shunt was found (normal: less than 12%). A transesophageal echocardiogram and a cardiac catheterization showed the presence of a PFO. A percutaneous closure was performed.


Assuntos
Forame Oval Patente , Idoso , Cateterismo Cardíaco , Dispneia , Ecocardiografia Transesofagiana , Feminino , Humanos , Hipóxia , Resultado do Tratamento
19.
BMC Cardiovasc Disord ; 19(1): 203, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438858

RESUMO

BACKGROUND: Cellular therapies have been increasingly applied to diverse human diseases. Intracoronary infusion of bone marrow-derived mononuclear cells (BMMNC) has demonstrated to improve ventricular function after acute myocardial infarction. However, less information is available about the role of BMMNC therapy for the treatment of dilated myocardiopathies (DCs) of non-ischemic origin. This article presents the methodological description of a study aimed at investigating the efficacy of intracoronary injection of autologous BMMNCs in the improvement of the ventricular function of patients with DC. METHODS: This randomised, placebo-controlled, double-blinded phase IIb clinical trial compares the improvement on ventricular function (measured by the changes on the ejection fraction) of patients receiving the conventional treatment for DC in combination with a single dose of an intracoronary infusion of BMMNCs, with the functional recovery of patients receiving placebo plus conventional treatment. Patients assigned to both treatment groups are monitored for 24 months. This clinical trial is powered enough to detect a change in Left Ventricular Ejection Fraction (LVEF) equal to or greater than 9%, although an interim analysis is planned to re-calculate sample size. DISCUSSION: The study protocol was approved by the Andalusian Coordinating Ethics Committee for Biomedical Research (Comité Coordinador de Ética en Investigación Biomédica de Andalucia), the Spanish Medicines and Medical Devices Agency (Agencia Española de Medicamentos y Productos Sanitarios), and is registered at the EU Clinical Trials Register (EudraCT: 2013-002015-98). The publication of the trial results in scientific journals will be performed in accordance with the applicable regulations and guidelines to clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02033278 (First Posted January 10, 2014): https://clinicaltrials.gov/ct2/show/NCT02033278 ; EudraCT number: 2013-002015-98, EU CT Register: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-002015-98 . Trial results will also be published according to the CONSORT statement at conferences and reported peer-reviewed journals.


Assuntos
Transplante de Medula Óssea , Cardiomiopatia Dilatada/cirurgia , Função Ventricular Esquerda , Adolescente , Adulto , Idoso , Transplante de Medula Óssea/efeitos adversos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Espanha , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
20.
J Am Chem Soc ; 140(35): 11067-11075, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30102533

RESUMO

A highly diastereo- and enantioselective, scalable Pd-catalyzed dynamic kinetic asymmetric Heck reaction of heterobiaryl sulfonates with electron-rich olefins is described. The coupling of 2,3-dihydrofuran or N-boc protected 2,3-dihydropyrrole with a variety of quinoline, quinazoline, phthalazine, and picoline derivatives takes place with simultaneous installation of central and axial chirality, reaching excellent diastereo- and enantiomeric excesses when in situ formed [Pd0/DM-BINAP] was used as the catalyst, with loadings reduced down to 2 mol % in large scale reactions. The coupling of acyclic, electron-rich alkenes can also be performed using a [Pd0/Josiphos ligand] to obtain axially chiral heterobiaryl α-substituted alkenes in high yields and enantioselectivities. Products from Boc-protected 2,3-dihydropyrrole can be easily transformed into N, N ligands or appealing axially chiral, bifunctional proline-type organocatalysts. Computational studies suggest that a ß-hydride elimination is the stereocontrolling step, in agreement with the observed stereochemical outcome of the reaction.

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