RESUMEN
Hepatic adeno-associated viral (AAV) gene transfer has the potential to cure the X-linked bleeding disorder hemophilia A. However, declining therapeutic coagulation factor VIII (FVIII) expression has plagued clinical trials. To assess the mechanistic underpinnings of this loss of FVIII expression, we developed a hemophilia A mouse model that shares key features observed in clinical trials. Following liver-directed AAV8 gene transfer in the presence of rapamycin, initial FVIII protein expression declines over time in the absence of antibody formation. Surprisingly, loss of FVIII protein production occurs despite persistence of transgene and mRNA, suggesting a translational shutdown rather than a loss of transduced hepatocytes. Some of the animals develop ER stress, which may be linked to hepatic inflammatory cytokine expression. FVIII protein expression is preserved by interleukin-15/interleukin-15 receptor blockade, which suppresses CD8+ T and natural killer cell responses. Interestingly, mice with initial FVIII levels >100% of normal had diminishing expression while still under immune suppression. Taken together, our findings of interanimal variability of the response, and the ability of the immune system to shut down transgene expression without utilizing cytolytic or antibody-mediated mechanisms, illustrate the challenges associated with FVIII gene transfer. Our protocols based upon cytokine blockade should help to maintain efficient FVIII expression.
Asunto(s)
Factor VIII , Interleucina-15 , Ratones , Animales , Factor VIII/genética , Interleucina-15/genética , Sirolimus/farmacologíaRESUMEN
The acute respiratory illness caused by coronavirus SARS-CoV-2 (COVID-19) has spread throughout the world, causing significant morbidity and mortality. OBJECTIVES: To assess clinical and laboratory variables measured at hospital admission associated with clinically relevant adverse outcomes in patients hospitalized with community-acquired pneumonia caused by coronavirus SARSCoV-2. METHODS: We conducted a descriptive prospective study in adult patients hospitalized due to COVID-19-associated pneumonia at the UC Christus Health Network. The adverse events examined were ICU admission, need for mechanical ventilation, prolonged length of stay, and hospital mortality. We analyzed predictive variables using univariate and multivariate analysis in a logistic regression model. RESULTS: We evaluated 710 COVID-19-associated pneumonia hospitalized patients aged 59 ± 17 years; 55% were males. 76% of the cohort presented comorbidities, mainly hypertension (45%), diabetes (24%), and hypothyroidism (10%); 42% of the cohort received treatment in critical care units, 16.3% required mechanical ventilation, the mean hospital stay was 15 days, and 11.4% died in the hospital. Age, comorbidities, especially cardiovascular, metabolic, and chronic kidney disease, altered mental status and vital signs (tachypnea, hypoxemia) at hospital admission, renal failure, and elevated biomarkers of systemic inflammation were associated with ICU admission, prolonged hospital stay, and death. Men had a higher risk of ICU admission, connection to mechanical ventilation, and prolonged hospital stay but did not have higher fatalities. CONCLUSION: Age, male sex, comorbidities, altered mental status and vital signs, renal dysfunction, and elevation of inflammatory parameters were associated with a higher risk of severe COVID-19. These may serve as useful baseline parameters in developing prediction tools for COVID-19 prognosis.
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COVID-19 , Infecciones Comunitarias Adquiridas , Hospitalización , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Femenino , Infecciones Comunitarias Adquiridas/virología , Estudios Prospectivos , Anciano , Hospitalización/estadística & datos numéricos , Adulto , Tiempo de Internación/estadística & datos numéricos , Respiración Artificial/estadística & datos numéricos , Mortalidad Hospitalaria , Factores de Riesgo , Comorbilidad , InmunocompetenciaRESUMEN
BACKGROUND: Severity assessment in adult patients with community-acquired pneumonia (CAP) allows to guide the site of care (ambulatory or hospitalization), diagnostic workup and treatment. AIM: To examine the performance of twelve severity predictive indexes (CRB65, CURB65, PSI, SCAP, SMART-COP, REA-ICU, ATS minor criteria, qSOFA, CALL, COVID GRAM, 4C, STSS) in adult patients hospitalized for CAP associated with SARS-CoV-2. MATERIAL AND METHODS: Prospective clinical study conducted between April 1 and September 30, 2020 in adult patients hospitalized for CAP associated with COVID-19 in a clinical hospital. The recorded adverse events were admission to the critical care unit, use of mechanical ventilation (MV), prolonged length of stay, and hospital mortality. The predictive rules were compared based on their sensitivity, specificity, predictive values, and area under the receiver operator characteristic (ROC) curve. RESULTS: Adverse events were more common and hospital stay longer in the high-risk categories of the different prognostic indices. CURB-65, PSI, SCAP, COVID GRAM, 4 C and STSS predicted the risk of death accurately. PSI, SCAP, ATS minor criteria, CALL and 4 C criteria were sensitive in predicting the risk of hospital mortality with high negative predictive value. The performance of different prognostic indices decreased significantly for the prediction of ICU admission, use of mechanical ventilation, and prolonged hospital length of stay. CONCLUSIONS: The performance of the prognostic indices differs significantly for the prediction of adverse events in immunocompetent adult patients hospitalized for community-acquired pneumonia associated with COVID-19.
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COVID-19 , Infecciones Comunitarias Adquiridas , Neumonía , Adulto , Humanos , SARS-CoV-2 , Estudios Prospectivos , Pronóstico , Infecciones Comunitarias Adquiridas/diagnóstico , Índice de Severidad de la Enfermedad , Estudios RetrospectivosRESUMEN
The main strategies against Triatoma infestans (primary vector responsible for the Chagas disease transmission) are the elimination or reduction of its abundance in homes through the application of insecticides or repellents with residual power, and environmental management through the improvement of housing. The use of plant-derived compounds as a source of therapeutic agents (i.e., essential oils from aromatic plants and their components) is a valuable alternative to conventional insecticides and repellents. Essential oil-based insect repellents are environmentally friendly and provide reliable personal protection against the bites of mosquitoes and other blood-sucking insects. This study investigates, for the first time to our knowledge, the potential repellent activity of Zuccagnia punctata essential oil (ZEO) and poly(ε-caprolactone) matrices loaded with ZEO (ZEOP) prepared by solvent casting. The analysis of its essential oil from aerial parts by GC-FID and GC-MS, MS allowed the identification of 25 constituents representing 99.5% of the composition. The main components of the oil were identified as (-)-5,6-dehydrocamphor (62.4%), alpha-pinene (9.1%), thuja-2, 4 (10)-diene (4.6%) and dihydroeugenol (4.5%). ZEOP matrices were homogeneous and opaque, with thickness of 800 ± 140 µm and encapsulation efficiency values above 98%. ZEO and ZEOP at the lowest dose (0.5% wt./wt., 96 h) showed a repellency of 33 and 73% respectively, while at the highest dose (1% wt./wt., 96 h) exhibited a repellent activity of 40 and 66 %, respectively. On the other hand, until 72 h, ZEO showed a strong repellent activity against T. infestans (88% repellency average; Class V) to both concentrations, compared with positive control N-N diethyl-3-methylbenzamide (DEET). The essential oils from the Andean flora have shown an excellent repellent activity, highlighting the repellent activity of Zuccagnia punctata. The effectiveness of ZEO was extended by its incorporation in polymeric systems and could have a potential home or peridomiciliary use, which might help prevent, or at least reduce, Chagas' disease transmission.
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Fabaceae/química , Repelentes de Insectos/farmacología , Mosquitos Vectores/efectos de los fármacos , Aceites Volátiles/farmacología , Triatoma/efectos de los fármacos , Animales , Alcanfor/análogos & derivados , Alcanfor/análisis , Eugenol/análogos & derivados , Eugenol/análisis , Repelentes de Insectos/química , Aceites Volátiles/química , Poliésteres/químicaRESUMEN
Plants in the Amaryllidaceae family synthesize a diversity of bioactive alkaloids. Some of these plant species are not abundant and have a low natural multiplication rate. The aims of this work were the alkaloids analysis of a Habranthus cardenasianus bulbs extract, the evaluation of its inhibitory activity against cholinesterases, and to test several propagation strategies for biomass production. Eleven compounds were characterized by GC-MS in the alkaloid extract, which showed a relatively high proportion of tazettine. The known alkaloids tazettine, haemanthamine, and the epimer mixture haemanthidine/6-epi-haemanthidine were isolated and identified by spectroscopic methods. Inhibitory cholinesterases activity was not detected. Three forms of propagation were performed: bulb propagation from seed, cut-induced bulb division, and micropropagated bulbs. Finally, different imbibition and post-collection times were evaluated in seed germination assays. The best propagation method was cut-induced bulb division with longitudinal cuts into quarters (T1) while the best conditions for seed germination were 0-day of post-collection and two days of imbibition. The alkaloids analyses of the H. cardenasianus bulbs showed that they are a source of anti-tumoral alkaloids, especially pretazettine (tazettine) and T1 is a sustainable strategy for its propagation and domestication to produce bioactive alkaloids.
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Alcaloides/análisis , Alcaloides/farmacología , Amaryllidaceae/química , Amaryllidaceae/crecimiento & desarrollo , Inhibidores de la Colinesterasa/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Alcaloides de Amaryllidaceae/análisis , Biomasa , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Cromatografía de Gases y Espectrometría de Masas , Germinación , Estructura Molecular , Fenantridinas/análisis , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Factores de TiempoRESUMEN
BACKGROUND: COVID-19 is a serious public health problem worldwide. AIM: To describe the clinical features of COVID-19 infection in adult patients consulting at an Emergency Service. MATERIAL AND METHODS: Descriptive prospective study of adult patients with suspected COVID-19 consulting between April 1 and July 31, 2020, at the Emergency Service of a clinical hospital. Clinical features, chronic comorbidities and demographic data were recorded. RESULTS: We assessed 2,958 adult patients aged 42 ± 15 years (46% males). In 54% of them, COVID-19 infection was confirmed, 40% had preexisting diseases, especially hypertension (15%), hypothyroidism (6%), diabetes (6%), asthma (5%) and obesity (6%). The main clinical manifestations associated with COVID-19 were general malaise (79%), anorexia (38%), myalgia (64%), fever (52%), headache (70%), anosmia/dysgeusia (60%), cough (56%), dyspnea (54%) and diarrhea (36%). In the multivariate analysis, the main clinical predictors of COVID-19 infection were malaise, anorexia, fever, myalgia, headache, nasal congestion, cough, expectoration, anosmia/dysgeusia, and history of close contact with a SARS-CoV-2 patient. Odynophagia and chest discomfort were negative predictors of the disease. The history of fever associated with anorexia, cough, and dyspnea or anosmia/dysgeusia and close contact with a SARS-CoV-2 patient had high specificity and positive predictive value for COVID-19 infection. CONCLUSIONS: Clinical features of COVID-19 infection were highly unspecific in these patients. Clinical diagnostic prediction models could be useful to support healthcare decision making at primary care setting.
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COVID-19 , Servicios Médicos de Urgencia , Adulto , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/epidemiología , Tos/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , SARS-CoV-2RESUMEN
A new series of furan embelin derivatives was synthesized and characterized as ATP-competitive CK2 inhibitors. The new compounds were efficiently synthesized using a multicomponent approach from embelin (1), aldehydes and isonitriles through a Knoevenagel condensation/Michael addition/heterocyclization. Several compounds with inhibitory activities in the low micromolar or even submicromolar were identified. The most active derivative was compound 4l (2-(tert-butylamino)-3-(furan-3-yl)-5-hydroxy-6-undecylbenzofuran-4,7-dione) with an IC50 value of 0.63 µM. It turned out to be an ATP competitive CK2 inhibitor with a Ki value determined to be 0.48 µM. Docking studies allowed the identification of key ligand-CK2 interactions, which could help to further optimize this family of compounds as CK2 inhibitors.
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Benzoquinonas/química , Benzoquinonas/farmacología , Quinasa de la Caseína II/antagonistas & inhibidores , Diseño de Fármacos , Inhibidores de Proteínas Quinasas/farmacología , Adenosina Trifosfato/metabolismo , Benzoquinonas/síntesis química , Unión Competitiva , Evaluación Preclínica de Medicamentos , Furanos/química , Humanos , Células MCF-7 , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Relación Estructura-ActividadRESUMEN
A library of embelin derivatives has been synthesized through a multicomponent reaction from embelin (1), aldehydes and privileged structures such as 4-hydroxycoumarin, 4-hydroxy-2H-pyran-2-one and 2-naphthol, in the presence of InCl3 as catalyst. This multicomponent reaction implies Knoevenagel condensation, Michael addition, intramolecular cyclization and dehydration. Many of the synthesized compounds were active and selective against Gram-positive bacteria, including one important multiresistant Staphylococcus aureus clinical isolate. It was found how the conjugation of diverse privileged substructure with embelin led to adducts having enhanced antibacterial activities.
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Antibacterianos/química , Antibacterianos/síntesis química , Benzoquinonas/química , Benzoquinonas/síntesis química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Benzoquinonas/farmacología , Bioensayo , Electrones , Pruebas de Sensibilidad Microbiana , Electricidad EstáticaRESUMEN
BACKGROUND: In December 2019, coronavirus disease 2019 (COVID-19) emerged in Wuhan city and spread rapidly throughout China and the world. AIM: To describe the clinical features, risk factors, and predictors of hospitalization in adult patients treated for acute respiratory infections associated with coronavirus SARS-CoV-2. MATERIAL AND METHODS: Descriptive prospective study of ambulatory and hospitalized adult patients with confirmed COVID-19 attended between April 1 and May 31, 2020. Clinical features, chronic comorbidities and demographic data were recorded, and patients were followed for two months as outpatients. RESULTS: We assessed 1,022 adults aged 41 ± 14 years (50% men) with laboratory-confirmed COVID-19. One-third had comorbidities, specially hypertension (12.5%), hypothyroidism (6.6%), asthma (5.4%) and diabetes (4.5%). Hospital admission was required in 11%, 5.2% were admitted to critical care unit and 0.9% were connected to mechanical ventilation. Common symptoms included fatigue (55.4%), fever (52.5%), headache (68.6%), anosmia/dysgeusia (53.2%), dry cough (53.4%), dyspnea (27.4%) and diarrhea (35.5%). One third of patients reported persistence of symptoms at one-month follow-up, specially fatigue, cough and dyspnea. In the multivariate analysis, age, fever, cough, dyspnea and immunosuppression were associated with hospitalization and ICU admission. Age, male sex and moderate-severe dyspnea were associated with requirement of mechanical ventilation. The main predictors of prolonged clinical course were female sex, presence of comorbidities, history of dyspnea, cough, myalgia and abdominal pain. CONCLUSIONS: Clinical features of COVID-19 were highly unspecific. Prediction models for severity, will help medical decision making at the primary care setting.
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COVID-19 , Infecciones por Coronavirus , Adulto , Comorbilidad , Infecciones por Coronavirus/epidemiología , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , SARS-CoV-2RESUMEN
The decoction of the local plant Baccharis grisebachii is used as a digestive, gastroprotective, external cicatrizing agent and antiseptic in Argentine. A lyophilized decoction (BLD) from the aerial parts of this plant was evaluated regarding its anti-ulcer, antioxidant and cytotoxic activities and the bioactivities were supported by UHPLC-MS metabolome fingerprinting which revealed the presence of several small bioactive compounds. The antioxidant properties were evaluated by DPPH, TEAC, FRAP and lipoperoxidation inhibition in erythrocytes methods, and the antibacterial activity was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The BLD showed a moderate free radical scavenging activity in the DPPH (EC50 = 106 µg/mL) and lipid peroxidation in erythrocytes assays (67%, at 250 µg/mL). However, the BLD had the highest gastroprotective effect at a dose of 750 mg/kg with a ninety-three percent inhibition of damage through a mechanism that involve NO and prostaglandins using the ethanol-induced gastric damage in a standard rat model. On the other hand, BLD does not induce cytotoxic changes on human tumor and no-tumor cell lines at the concentrations assayed. Regarding the metabolomic analysis, thirty-one compounds were detected and 30 identified based on UHPLC-OT-MS including twelve flavonoids, eleven cinnamic acid derivatives, one coumarin, one stilbene and two other different phenolic compounds. The results support that the medicinal decoction of Baccharis grisebachii is a valuable natural product with gastroprotective effects and with potential to improve human health that opens a pathway for the development of important phytomedicine products.
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Antioxidantes/química , Baccharis/química , Compuestos de Bifenilo/química , Cromatografía Líquida de Alta Presión , Cinamatos/química , Flavonoides/química , Células HCT116 , Humanos , Peroxidación de Lípido , Espectrometría de Masas , Picratos/químicaRESUMEN
BACKGROUND: Postponement of motherhood is one of the most striking sociodemographic changes of modernity. AIM: To evaluate the age of primiparous women giving birth at a public hospital in Santiago, Chile. MATERIAL AND METHODS: Retrospective study, assessing the age and nationality of all women whose delivery occurred between 2009 and 2017 in a single hospital. RESULTS: A total of 49,254 deliveries were registered: 43% were in primiparous women (73% Chilean and 27% foreign women). The proportion of foreign women increased from 12% in 2009 to more than 60% of total deliveries in 2017. Four percent of primiparous women were aged over 35 years of age and there was a steady increase in the age increase of primiparous women in the nine years of study. There was a higher proportion of normal-weight newborns among foreign women compared to their Chilean counterparts (86 and 81% respectively). CONCLUSIONS: In this sample of women attended at a public hospital, a steady increase in the age at first delivery was noted in a period of nine years. There was also a constant increase in the proportion of foreign women giving birth.
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Peso al Nacer , Hospitales Públicos/estadística & datos numéricos , Edad Materna , Clase Social , Adulto , Chile , Emigrantes e Inmigrantes/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Paridad , Embarazo , Estudios Retrospectivos , Factores Socioeconómicos , Adulto JovenRESUMEN
BACKGROUND: Women with obstructive sleep apnea-hypopnea syndrome (OSAS) are less likely to be assessed or to receive an appropriate diagnosis, and they may have poorer quality of life and survival rates. AIM: To assess gender-specific clinical differences in adult patients with OSAS. MATERIAL AND METHODS: A standardized clinical questionnaire and four sleep questionnaires (Berlin, Epworth Sleepiness Scale, STOP and STOP-Bang) were administered and anthropometric data were measured. Patients underwent an overnight in-laboratory polysomnography to confirm the diagnosis of OSAS. Receiver operating characteristic curves, sensitivity and specificity of clinical manifestations and sleep questionnaires were calculated. RESULTS: Of 1,464 screened patients, 509 were female, 58.6% had moderate to severe OSAS. Clinical variables associated with OSAS risk in women were age, insomnia, nocturia, hypertension and cervical circumference. Paired by age and respiratory events, the snoring frequency was similar in both genders, although witnessed apneas and high cervical circumference and waist/hip ratio were more common in males. Morning headaches, insomnia, excessive daytime sleepiness, depression, anxiety and poor quality of sleep were more common in women. Women were older than men, more obese (although with an obesity pattern less centrally distributed) and referred hypertension, diabetes, depression and hypothyroidism with higher frequency. Sleep questionnaires performance were similar in both sexes. CONCLUSIONS: It is likely that women with OSAS may partially be underdiagnosed due to circumstances related to a different OSAS clinical expression.
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Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/epidemiología , Encuestas y Cuestionarios/normas , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Antropometría , Chile/epidemiología , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Calidad de Vida , Factores de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Distribución por Sexo , Factores Sexuales , Estadísticas no Paramétricas , Adulto JovenRESUMEN
The seriated extracts of petroleum ether (PE-E), dichloromethane (DCM-E) and methanol extracts (MeOH-E) from the aerial parts of the native South American plant Tetraglochin ameghinoi (Rosaceae), were evaluated regarding their antioxidant and antibacterial activities. The antioxidant properties were evaluated by free radical scavenging methods (DPPH and TEAC), ferric-reducing antioxidant power (FRAP) and lipoperoxidation in erythrocytes (LP), while the antibacterial activity was performed against Gram-positive and Gram-negative bacteria according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The chemical and biological analyses of this plant are very important since this bush is currently used in traditional medicine as a cholagogue and digestive. The polar MeOH-E showed the highest antioxidant activities (17.70 µg/mL in the DPPH assay, 381.43 ± 22.38 mM TE/g extract in the FRAP assay, 387.76 ± 91.93 mg TE/g extract in the TEAC assay and 93.23 + 6.77% in the LP assay) and it was selected for chromatographic isolation of its components. These components were found to be four acetophenones, including the new phloracetophenone glucoside: 4',6',-dihydroxy-2'-O-(6â³-acetyl)-ß-d-glucopyranosylacetophenone or IUPAC name: (6-(2-acetyl-3,5-dihydroxyphenoxy)-3,4,5-trihydroxytetrahydro-2H-pyran-2-yl)methyl acetate, whose structure was elucidated by NMR and MS methods. In addition, twenty-six compounds, including five of these acetophenone derivatives, two sugars, six flavonoids, eleven phenolic acids and two triterpenes, were identified based on UHPLC-OT-MS and PDA analysis on the MeOH-E. The results support the medicinal use of the plant.
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Antioxidantes/metabolismo , Metaboloma/fisiología , Metabolómica , Rosaceae/metabolismo , Antioxidantes/química , Rosaceae/químicaRESUMEN
Annona emarginata (Schltdl.) H. Rainer, commonly known as "arachichú", "araticú", "aratigú", and "yerba mora", is a plant that grows in Argentina. Infusions and decoctions are used in folk medicine as a gargle against throat pain and for calming toothache; another way to use the plant for these purposes is chewing its leaves. Extracts from bark, flowers, leaves, and fruits from A. emarginata were subjected to antibacterial assays against a panel of Gram (+) and Gram (-) pathogenic bacteria according to Clinical and Laboratory Standards Institute protocols. Extracts from the stem bark and leaves showed moderate activity against the bacteria tested with values between 250â»1000 µg/mL. Regarding flower extracts, less polar extracts (hexane, dichloromethane) showed very strong antibacterial activity against methicillin-sensitive Staphylococcus aureus ATCC 25923 and methicillin-resistant S. aureus ATCC 43300 with values between 16â»125 µg/mL. Additionally, hexane extract showed activity against Klebsiella pneumoniae (MIC = 250 µg/mL). The global methanolic extract of the fruits (MeOHGEF) was also active against the three strains mentioned above, with MICs values 250â»500 µg/mL. Bioassay-guided fractionation of MeOHGEF led to the isolation of a new main compound-(R)-2-(4-methylcyclohex-3-en-1-yl)propan-2-yl (E)-3-(4-hydroxyphenyl)acrylate (1). The structure and relative configurations have been determined by means of 1D and 2D NMR techniques, including COSY, HMQC, HMBC, and NOESY correlations. Compound 1 showed strong antimicrobial activity against all Gram (+) species tested (MICs = 3.12â»6.25 µg/mL). In addition, the synthesis and antibacterial activity of some compounds structurally related to compound 1 (including four new compounds) are reported. A SAR study for these compounds was performed based on the results obtained by using molecular calculations.
Asunto(s)
Annona/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Argentina , Flores/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Medicina Tradicional , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Corteza de la Planta/química , Hojas de la Planta/químicaRESUMEN
A highly efficient and regioselective approach to new polycyclic embelin derivatives through a domino Knoevenagel condensation/intramolecular hetero Diels-Alder reaction using O-(arylpropynyloxy)-salicylaldehydes in the presence of ethylenediamine diacetate (EDDA) is reported. This organocatalyzed protocol is compatible toward a wide range of aryl-substituted alkynyl ethers with electron-donating and electron-withdrawing groups. When other active methylene compounds were subjected to this domino reaction the corresponding adducts were obtained in high yield.
RESUMEN
A series of dihydropyran embelin derivatives was synthesized through a direct and highly efficient approach based on a domino Knoevenagel intramolecular hetero-Diels-Alder reaction from natural embelin (1), using unsaturated aldehydes in the presence of organocatalysts such as ethylendiamine diacetate or l-proline. The aliphatic aldehydes yielded exclusively trans adducts, while mixtures of trans and cis isomers were found in reactions with aromatic aldehydes, with the cis form always predominating. Some of the compounds obtained were active and selective against Gram-positive bacteria, including multiresistant Staphylococcus aureus clinical isolates.
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Antibacterianos/síntesis química , Antibacterianos/farmacología , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/farmacología , Benzoquinonas/síntesis química , Benzoquinonas/farmacología , Staphylococcus aureus/efectos de los fármacos , Aldehídos/química , Antibacterianos/química , Antiinflamatorios no Esteroideos/química , Benzoquinonas/química , Catálisis , Bacterias Grampositivas/efectos de los fármacos , Estructura Molecular , Prolina/química , EstereoisomerismoRESUMEN
Two new alkaloids, 4-O-methylnangustine (1) and 7-hydroxyclivonine (2) (montanine and homolycorine types, respectively), and four known alkaloids were isolated from the bulbs of Hippeastrum argentinum, and their cholinesterase-inhibitory activities were evaluated. These compounds were identified using GC-MS, and their structures were defined by physical data analysis. Compound 2 showed weak butyrylcholinesterase (BuChE)-inhibitory activity, with a half-maximal inhibitory concentration (IC50) value of 67.3 ± 0.09 µM. To better understand the experimental results, a molecular modeling study was also performed. The combination of a docking study, molecular dynamics simulations, and quantum theory of atoms in molecules calculations provides new insight into the molecular interactions of compound 2 with BuChE, which were compared to those of galantamine.
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Alcaloides de Amaryllidaceae/farmacología , Butirilcolinesterasa/efectos de los fármacos , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/aislamiento & purificación , Argentina , Cromatografía de Gases y Espectrometría de Masas , Concentración 50 Inhibidora , Modelos Moleculares , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/químicaRESUMEN
The synthesis, in vitro evaluation and conformational study of several small-size peptides acting as antibacterial agents are reported. Among the compounds evaluated, the peptides Arg-Gln-Ile-Lys-Ile-Trp-Arg-Arg-Met-Lys-Trp-Lys-Lys-NH2 , Arg-Gln-Ile-Lys-Ile-Arg-Arg-Met-Lys-Trp-Arg-NH2 , and Arg-Gln-Ile-Trp-Trp-Trp-Trp-Gln-Arg-NH2 exhibited significant antibacterial activity. These were found to be very active antibacterial compounds, considering their small molecular size. In order to better understand the antibacterial activity obtained for these peptides, an exhaustive conformational analysis was performed, using both theoretical calculations and experimental measurements. Molecular dynamics simulations using two different media (water and trifluoroethanol/water) were employed. The results of these theoretical calculations were corroborated by experimental circular dichroism measurements. A brief discussion on the possible mechanism of action of these peptides at molecular level is also presented. Some of the peptides reported here constitute very interesting structures to be used as starting compounds for the design of new small-size peptides possessing antibacterial activity.
Asunto(s)
Antibacterianos/química , Proteínas Portadoras/química , Oligopéptidos/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Péptidos de Penetración Celular , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana , Simulación de Dinámica Molecular , Oligopéptidos/síntesis química , Oligopéptidos/farmacología , Conformación Proteica , Salmonella/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacosRESUMEN
In order to searching a potential novel approach to pistachio utilization, the chemical and nutritional quality of oil and flour from natural, roasted, and salted roasted pistachios from Argentinian cultivars were evaluated. The pistachio oil has high contents of oleic and linoleic acid (53.5 - 55.3, 29 - 31.4 relative abundance, respectively), tocopherols (896 - 916 µg/g oil), carotenoids (48 - 56 µg/g oil) and chlorophylls (41 - 70 µg/g oil), being a good source for commercial edible oil production. The processing conditions did not affect significantly the fatty acid and minor composition of pistachio oil samples. The content of total phenolic (TP) and flavonoids (FL) was not significantly modified by the roasting process, whereas free radical scavenging (DPPH radical) and antioxidant power decreased in a 20% approximately. Furthermore, salted roasted pistachio flour (SRPF) showed a significant decrease in TP and FL content in comparison to others samples. The phenolic profile of pistachio flours evaluated by LC-ESI-QTOF-MS. The major compounds identified were (+)-catechin (38 - 65.6 µg/g PF d.w.), gallic acid (23 - 36 µg/g PF d.w.) and cyanidin-3-O-galactoside (21 - 23 µg/g PF d.w.). The treatments effects on the phenolics constituents of pistachio flour. Roasting caused a significant reduction of some phenolics, gallic acid and (+)- catechin, and increased others, naringenin and luteolin. Salting and roasting of pistachio increased garlic acid and naringenin content.
In order to searching a potential novel approach to pistachio utilization, the chemical and nutritional quality of oil and flour from natural, roasted, and salted roasted pistachios from Argentinian cultivars were evaluated. The pistachio oil has high contents of oleic and linoleic acid (53.555.3, 2931.4 relative abundance, respectively), tocopherols (896916 µg/g oil), carotenoids (4856 µg/g oil) and chlorophylls (4170 µg/g oil), being a good source for commercial edible oil production. The processing conditions did not affect significantly the fatty acid distribution and minor components of pistachio oil samples. The roasting process not diminish total phenolic (TP) and flavonoids (FL) content significantly compared to natural pistachio flour (NPF), even so reduced the DPPH antioxidant capacity (approximately 20 %) in the roasted pistachio flour (RPF). Furthermore, salted roasted pistachio flour (SRPF) showed a slight and significant decrease on TP and FL content in relation to the others samples. The phenolic profile of pistachio flours were evaluated by LC-ESI-QTOF-MS. The major compounds were (+)-catechin (3865.6 µg/g PF d.w.), gallic acid (2336 µg/g PF d.w.) and cyanidin-3-O-galactoside (2123 µg/g PF d.w.). The treatments have different effects on the phenolics constituents of pistachio flour. Roasting caused a significant reduction of some phenolics, gallic acid and (+)-catechin, and increased others, naringenin and luteolin. Otherwise, salting and roasting of pistachio increased levels of gallic acid and naringenin. These results suggest that Argentinian pistachio oil and flour could be considered as ingredients into applications that enhance human health.
RESUMEN
New nitrosopyrimidines were synthesized and evaluated as potential antibacterial agents. Different compounds structurally related with 4,6-bis(alkyl or arylamino)-5-nitrosopyrimidines were evaluated. Some of these nitrosopyrimidines displayed significant antibacterial activity against human pathogenic bacteria. Among them compounds 1c, 2a-c, and 9a-c exhibited remarkable activity against methicillin-sensitive and -resistant Staphylococcus aureus, Escherichia coli, Yersinia enterocolitica, and Salmonella enteritidis. A detailed structure-activity relationship study, supported by theoretical calculations, aided us to identify and understand the minimal structural requirements for the antibacterial action of the nitrosopyrimidines reported here. Thus, our results have led us to identify a topographical template that provides a guide for the design of new nitrosopyrimidines with antibacterial effects.