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1.
s.l; CONETEC; 19 abr. 2022.
Não convencional em Espanhol | LILACS, BRISA/RedTESA | ID: biblio-1367179

RESUMO

INTRODUCCIÓN: El molnupiravir (EIDD-2801 o MK-4482-013) es un profármaco de un análogo de ribonucleósido antivírico, que se administra por vía oral, tiene actividad contra el SARS-CoV-2 in vitro, y que se encuentra actualmente bajo investigación para su uso en COVID-19. Actualmente la Administración de Alimentos y Medicamentos de los Estados Unidos (FDA, su sigla del inglés Food and Drug Administration) ha aprobado, bajo el esquema de Autorización de Uso de Emergencia, la comercialización de molnupiravir en adultos con COVID-19 de leve a moderado, que tienen un alto riesgo de progresión a enfermedad grave, incluida la hospitalización o la muerte, y para quienes los tratamientos alternativos autorizados por la FDA no son accesibles o clínicamente apropiadas. (14) La Agencia Europea de Medicamentos (EMA, su sigla del inglés European Medicine Agency) y la Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) aún no han autorizado su comercialización para ninguna indicación. (15) El 4 de noviembre del 2021 la Agencia Reguladora de Medicamentos y Productos Sanitarios de Reino Unido se ha convertido en el primer país del Mundo en autorizar su comercialización en personas que tienen COVID-19 de leve a moderado y al menos un factor de riesgo para desarrollar una enfermedad grave (como obesidad, edad avanzada (> 60 años), diabetes mellitus o enfermedades cardíacas). OBJETIVO: El objetivo del presente informe es evaluar parámetros de eficacia, seguridad, conveniencia y recomendaciones disponibles acerca del empleo de molnupiravir para el tratamiento de pacientes con COVID-19 en Argentina. MÉTODOS: Efectos en la Salud: Teniendo en cuenta la velocidad con la que la información relacionada a la pandemia aparece y se modifica, se desarrolló un protocolo sustentado en proyectos que resume activamente la evidencia científica a medida que la misma se hace disponible. Con este fin se utilizó la plataforma L- ove de Epistemonikos https://app.iloveevidence.com/topics para identificar revisiones sistemáticas "vivas". Se seleccionaron aquellas con una calidad metodológica apropiada evaluada a través de la herramienta AMSTAR-2, y que a su vez llevaran un proceso de actualización frecuente. (17) De cada una de las revisiones sistemáticas identificadas se extractaron los efectos de la intervención sobre los desenlaces priorizados como importantes o críticos y la certeza en dichos efectos. Para la priorización de los desenlaces se adoptó una perspectiva desde el paciente considerando sus potenciales preferencias. La selección se realizó por consenso entre los autores y supervisores del informe considerando los resultados de múltiples ejercicios de priorización publicados, realizados en el marco del desarrollo de distintas guías de práctica clínica. Se seleccionaron "mortalidad", "ingreso en asistencia ventilatoria mecánica", "tiempo hasta resolución de síntomas", "hospitalización", "eventos adversos graves" como desenlaces críticos. Adicionalmente, se extractaron datos relacionados con efectos de subgrupo potencialmente relevantes para la toma de decisión, con especial énfasis en el tiempo de evolución, la severidad de la enfermedad y el estado de vacunación. En los casos en que no fue reportado por las revisiones sistemáticas incluidas, se calculó el efecto absoluto de las intervenciones en pacientes vacunados, tomando el riesgo basal reportado para pacientes no vacunados multiplicado por un riesgo relativo de 0,1 según el efecto de la vacunación observado en distintos estudios y sistemas de vigilancia. (8,10,18,19) Para confeccionar las conclusiones en el efecto de las intervenciones evaluadas sobre los desenlaces priorizados, utilizamos lineamientos publicados, específicamente desarrollados a tal fin. Implementación: Este dominio contempla dos subdominios: la existencia de barreras y facilitadores en nuestro contexto para la implementación de la tecnología evaluada no consideradas en los otros dominios analizados, y los costos comparativos en relación con otras intervenciones similares. Con el objetivo de emitir un juicio de valor sobre la magnitud de dichos costos, en pacientes hospitalizados se utilizó como comparador al tratamiento con dexametasona, que ha demostrado ser una intervención accesible y de beneficios importantes en el contexto analizado. Recomendaciones: Para la identificación de recomendaciones sustentadas en evidencia y actualizadas, se utilizó la plataforma COVID recmap. Se seleccionaron aquellas guías con rigor metodológico apropiado según la herramienta AGREE II (> 70%) y se incorporaron sus recomendaciones al informe. RESULTADOS: Se identificaron dos revisiones sistemáticas que cumplieron con los criterios de inclusión del presente informe. Se identificaron seis ECA que incluyeron 3.653 pacientes con COVID-19, en los que se administró molnupiravir en comparación con el mejor estándar de atención. CONCLUSIONES: El cuerpo de la evidencia muestra que existe incertidumbre en el efecto de molnupiravir sobre la mortalidad (certeza muy baja ⨁◯◯◯). Molnupiravir probablemente reduzca las hospitalizaciones en pacientes con enfermedad leve de reciente comienzo y factores de riesgo para progresión a enfermedad severa. Sin embargo, la magnitud de la reducción solo resulta importante (mayor a 1%) para pacientes sin esquema de vacunación completo o con riesgo de respuesta inmune inapropriada. La tecnología no está autorizada para su comercialización por la Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) de nuestro país al momento de la fecha de realización del presente informe y se encuentra disponible en forma limitada en una sola provincia. Asimismo, el costo comparativo estimado es elevado, más aún teniendo en cuenta la elevada población objetivo a ser tratada. Las guías de práctica clínica de alta calidad metodológica actualizadas sugieren a favor de usar molnupiravir en pacientes con alto riesgo de hospitalización, no vacunados y con factores de riesgo (edad e inmunocomprometidos).


Assuntos
Humanos , Ribonucleosídeos/uso terapêutico , Pró-Fármacos/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , COVID-19/tratamento farmacológico , Eficácia , Análise Custo-Benefício
2.
Small ; 18(16): e2106269, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35266630

RESUMO

Exploring appropriate precursors has been proposed to be a promising strategy for the creation of artificial enzymes that are emerging as alternatives of natural enzymes. Herein, inspired by the catalytic activities of ribose nucleic acid, using ribonucleosides as precursors including adenosine, guanosine, cytidine, and uridine, respectively, four carbonic aggregates, namely, carbon dots (A-CDs, G-CDs, C-CDs, and U-CDs) to mimic artificial enzymes are synthesized. All the CDs show a planar graphene-like structure and thus can intercalatively bind with DNA double helix. Different from the other three CDs, the uridine-derived U-CDs exhibit unique catalytic property, which can mediate the topological transformation of DNA from supercoiled to nicked open-circular conformation. U-CDs can catalyze oxidation of O2 to generate singlet oxygen 1 O2 via a Haber-Weiss reaction, and consequently mediate oxidative cleavage of phosphate backbone in DNA and release the torsional energy stored in supercoiled DNA. Explorations reveal that the unique highly active oxygenated species, namely, quinone groups that are on the edge of U-CDs, play a key role in the catalytic production of 1 O2 . This work represents a new insight that using natural biomolecules in living systems as precursors can create new species beyond life.


Assuntos
Grafite , Pontos Quânticos , Ribonucleosídeos , Carbono/química , Catálise , Pontos Quânticos/química , Uridina
3.
Int J Mol Sci ; 23(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35269937

RESUMO

A comparative analysis of the transglycosylation conditions catalyzed by E. coli nucleoside phosphorylases, leading to the formation of 2'-deoxynucleosides, was performed. We demonstrated that maximal yields of 2'-deoxynucleosides, especially modified, can be achieved under small excess of glycosyl-donor (7-methyl-2'-deoxyguanosine, thymidine) and a 4-fold lack of phosphate. A phosphate concentration less than equimolar one allows using only a slight excess of the carbohydrate residue donor nucleoside to increase the reaction's output. A three-step methodology was elaborated for the preparative synthesis of purine-modified 2'-deoxyribonucleosides, starting from the corresponding ribonucleosides.


Assuntos
Ribonucleosídeos , Escherichia coli , Nucleosídeos/química , Pentosiltransferases , Fosfatos , Purina-Núcleosídeo Fosforilase , Purinas , Timidina
5.
Biochemistry ; 61(4): 239-251, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35104120

RESUMO

MA'AT analysis has been applied to methyl ß-d-ribofuranoside (3) and methyl 2-deoxy-ß-d-erythro-pentofuranoside (4) to demonstrate the ability of this new experimental method to determine multi-state conformational equilibria in solution. Density functional theory (DFT) was used to obtain parameterized equations for >20 NMR spin-coupling constants sensitive to furanose ring conformation in 3 and 4, and these equations were used in conjunction with experimental spin-couplings to produce unbiased MA'AT models of ring pseudorotation. These models describe two-state north-south conformational exchange consistent with results obtained from traditional treatments of more limited sets of NMR spin-couplings (e.g., PSEUROT). While PSEUROT, MA'AT, and aqueous molecular dynamics models yielded similar two-state models, MA'AT analysis gives more reliable results since significantly more experimental observables are employed compared to PSEUROT, and no assumptions are needed to render the fitting tractable. MA'AT models indicate a roughly equal distribution of north and south ring conformers of 4 in aqueous (2H2O) solution compared to ∼80% north forms for 3. Librational motion about the mean pseudorotation phase angles P of the preferred north and south conformers of 3 in solution is more constrained than that for 4. The greater rigidity of the ß-ribo ring may be caused by synergistic stereoelectronic effects and/or noncovalent (e.g., hydrogen-bonding) interactions in solution that preferentially stabilize north forms of 3. MA'AT analysis of oligonucleotides and other furanose ring-containing biomolecules promises to improve current experimental models of sugar ring behavior in solution and help reveal context effects on ring conformation in more complex biologically important systems.


Assuntos
Glicosídeos/química , Ribonucleosídeos/química , Configuração de Carboidratos , Teoria da Densidade Funcional , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular , Simulação de Dinâmica Molecular , Oligonucleotídeos/química , Açúcares/química , Água/química
6.
Am J Health Syst Pharm ; 79(6): 407-409, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35180292
7.
Drugs ; 82(3): 335-340, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35147913

RESUMO

Maribavir (LIVTENCITYTM), a cytomegalovirus (CMV) enzyme pUL97 kinase inhibitor, is being developed by Takeda Pharmaceuticals for the treatment of CMV infections. Maribavir was recently approved in the USA for the treatment of post-transplant CMV infection/disease that is refractory to treatment (with or without genotypic resistance) with ganciclovir, valganciclovir, cidofovir or foscarnet in adults and paediatric (≥ 12 years of age and weighing ≥ 35 kg) patients. This article summarizes the milestones in the development of maribavir leading to this first approval for CMV infections.


Assuntos
Infecções por Citomegalovirus , Ribonucleosídeos , Adulto , Antivirais/farmacologia , Antivirais/uso terapêutico , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Criança , Infecções por Citomegalovirus/tratamento farmacológico , Farmacorresistência Viral , Humanos , Ribonucleosídeos/farmacologia , Ribonucleosídeos/uso terapêutico
8.
Tohoku J Exp Med ; 256(1): 85-91, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35095030

RESUMO

Mizoribine may be a safe and effective treatment for children with steroid-dependent nephrotic syndrome (SDNS). However, predictors of treatment response and long-term outcomes after mizoribine discontinuation remain unknown. We retrospectively reviewed the clinical course of 22 children aged ≤ 10 years (median age, 5.3 years) with SDNS who received high-dose mizoribine as the initial steroid-sparing agent (SSA). Mizoribine was administered at a single daily dose of 10 mg/kg (maximum, 300 mg/day) after breakfast. The dose was adjusted to maintain 2-h post-dose mizoribine levels of > 3 µg/mL and was tapered off after 12 months of steroid-free remission. Patients who regressed to SDNS were switched from mizoribine to other SSAs. The primary endpoint was probability of survival without regression to SDNS after mizoribine initiation. Ten patients were able to discontinue SDNS (response group), whereas twelve were switched from mizoribine to other SSAs (non-response group) during a median observation period of 6.0 years after mizoribine. The steroid-dependent dose prior to mizoribine was significantly lower in the response group than in the non-response group (p < 0.05). The Kaplan-Meier analysis revealed that the probability of regression-free survival was significant higher in patients with steroid-dependent dose of < 0.25 mg/kg/day than in those with steroid-dependent dose of ≥ 0.25 mg/kg/day (p < 0.05). During a median follow-up of 5.5 years after mizoribine discontinuation, all but one patient did not develop SDNS. High-dose mizoribine may be an attractive treatment option as initial SSA in young children with low steroid-dependent dose for improved long-term outcomes.


Assuntos
Síndrome Nefrótica , Criança , Pré-Escolar , Humanos , Imunossupressores , Síndrome Nefrótica/tratamento farmacológico , Recidiva , Estudos Retrospectivos , Ribonucleosídeos , Esteroides
9.
Curr Protoc ; 2(1): e346, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35030289

RESUMO

The implementation of protecting groups for 2'-hydroxyl function of ribonucleosides is very demanding in that synthetic RNA sequences must be highly pure to ensure the safety and efficacy of nucleic acid-based drugs for treatment of human diseases. A synthetic approach consisting of a condensation reaction between 2'-O-aminoribonucleosides with ethyl pyruvate has been employed to provide stable 2'-O-imino-2-methyl propanoic acid ethyl esters. Conversion of these esters to fully protected ribonucleoside phosphoramidite monomers has allowed rapid and efficient incorporation of 2'-O-protected ribonucleosides into RNA sequences while minimizing the formation of process-related impurities during solid-phase synthesis. Two chimeric 20-mer RNA sequences have been synthesized and then exposed to a solution of sodium hydroxide to saponify the 2'-O-imino-2-methyl propanoic acid ethyl ester protecting groups to their sodium salts. When subjected to ion-exchange conditions at 65°C and near neutral pH, fully deprotected RNA sequences are isolated without production of alkylating side-products and/or formation of mutagenic nucleobase adducts. © 2022 Wiley Periodicals LLC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. Basic Protocol 1: Synthesis of uridine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 2: Synthesis of N6 -protected adenosine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 3: Synthesis of N4 -protected cytidine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 4: Synthesis of N2 -protected guanosine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 5: Automated solid-phase RNA synthesis and deprotection using 2'-O-imino-2-proponate-protected phosphoramidites.


Assuntos
Ribonucleosídeos , Técnicas de Síntese em Fase Sólida , Arabinonucleosídeos , Sequência de Bases , Humanos , RNA
10.
J Phys Chem Lett ; 13(2): 567-573, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35014840

RESUMO

Phosphorylation for ribonucleotide formation is a critical step in the origin of life but has had limited success due to the thermodynamic and kinetic constraints in aqueous media. Here, we report that the production of ribonucleotides from ribonucleosides in the presence of monopotassium phosphate (KH2PO4) spontaneously proceeded in aqueous microdroplets under ambient conditions and without using a catalyst. A full set of ribonucleotides including adenosine monophosphate (AMP), guanosine monophosphate (GMP), uridine monophosphate (UMP), and cytidine monophosphate (CMP) were generated on the scale of a few milliseconds. The aqueous microdroplets could transfer the ribonucleotides to oligoribonucleotides and showed mutual compatibility for individual phosphorylation. Conditions established the dependence of the conversion ratio on the droplet size and suggested that the condensation reactions occurred at or near the microdroplets' surface. This aqueous microdroplet approach also provides a route for elucidating phosphorylation chemistry in the prebiotic era.


Assuntos
Ribonucleotídeos/síntese química , Fosfatos/química , Fosforilação , Compostos de Potássio/química , Ribonucleosídeos/química , Água/química
11.
J Chromatogr A ; 1665: 462803, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35042139

RESUMO

Over 170 post-transcriptional RNA modifications have been described and are common in all kingdoms of life. These modifications range from methylation to complex chemical structures, with methylation being the most abundant. RNA modifications play a key role in RNA folding and function and their dysregulation in humans has been linked to several diseases such as cancer, metabolic diseases or neurological disorder. Nowadays, liquid chromatography-tandem mass spectrometry is considered the gold standard method for the identification and quantification of these modifications due to its sensitivity and accuracy. However, the analysis of modified ribonucleosides by mass spectrometry is complex due to the presence of positional isomers. In this scenario, optimal separation of these compounds by highly sensitive liquid chromatography combined with the generation of high-information spectra is critical to unequivocally identify them, especially in high-complex mixtures. Here we present an analytical method that comprises a new type of mixed-mode nano-flow liquid chromatography column combined with high- and low-collision energy data-independent mass spectrometric acquisition for the identification and quantitation of modified ribonucleosides. The method produces content-rich spectra and combines targeted and screening capabilities thus enabling the identification of a variety of modified nucleosides in biological matrices by single-shot liquid chromatographic analysis coupled to mass spectrometry.


Assuntos
Ribonucleosídeos , Ribonucleotídeos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Espectrometria de Massas
12.
J Med Microbiol ; 71(1)2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35037614

RESUMO

Introduction. Mycoplasma hominis is a bacterium belonging to the class Mollicutes. It causes acute and chronic infections of the urogenital tract. The main features of this bacterium are an absence of cell wall and a reduced genome size (517-622 protein-encoding genes). Previously, we have isolated morphologically unknown M. hominis colonies called micro-colonies (MCs) from the serum of patients with inflammatory urogenital tract infection.Hypothesis. MCs are functionally different from the typical colonies (TCs) in terms of metabolism and cell division.Aim. To determine the physiological differences between MCs and TCs of M. hominis and elucidate the pathways of formation and growth of MCs by a comparative proteomic analysis of these two morphological forms.Methodology. LC-MS proteomic analysis of TCs and MCs using an Ultimate 3000 RSLC nanoHPLC system connected to a QExactive Plus mass spectrometer.Results. The study of the proteomic profiles of M. hominis colonies allowed us to reconstruct their energy metabolism pathways. In addition to the already known pentose phosphate and arginine deamination pathways, M. hominis can utilise ribose phosphate and deoxyribose phosphate formed by nucleoside catabolism as energy sources. Comparative proteomic HPLC-MS analysis revealed that the proteomic profiles of TCs and MCs were different. We assume that MC cells preferably utilised deoxyribonucleosides, particularly thymidine, as an energy source rather than arginine or ribonucleosides. Utilisation of deoxyribonucleosides is less efficient as compared with that of ribonucleosides and arginine in terms of energy production. Thymidine phosphorylase DeoA is one of the key enzymes of deoxyribonucleosides utilisation. We obtained a DeoA overexpressing mutant that exhibited a phenotype similar to that of MCs, which confirmed our hypothesis.Conclusion. In addition to the two known pathways for energy production (arginine deamination and the pentose phosphate pathway) M. hominis can use deoxyribonucleosides and ribonucleosides. MC cells demonstrate a reorganisation of energy metabolism: unlike TC cells, they preferably utilise deoxyribonucleosides, particularly thymidine, as an energy source rather than arginine or ribonucleosides. Thus MC cells enter a state of energy starvation, which helps them to survive under stress, and in particular, to be resistant to antibiotics.


Assuntos
Mycoplasma hominis , Proteoma , Timidina/metabolismo , Arginina , Humanos , Infecções por Mycoplasma , Mycoplasma hominis/genética , Mycoplasma hominis/metabolismo , Fenótipo , Fosfatos , Ribonucleosídeos
13.
Chemistry ; 28(13): e202104472, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35018663

RESUMO

A new fluorescent ribonucleoside alphabet (mth N) consisting of pyrimidine and purine analogues, all derived from methylthieno[3,4-d]pyrimidine as the heterocyclic core, is described. Large bathochromic shifts and high microenvironmental susceptibility of their emission relative to previous alphabets derived from thieno[3,4-d]pyrimidine (th N) and isothiazole[4,3-d]pyrimidine (tz N) scaffolds are observed. Subjecting the purine analogues to adenosine deaminase, guanine deaminase and T7 RNA polymerase indicate that, while varying, all but one enzyme tolerate the corresponding mth N/mth NTP substrates. The robust emission quantum yields, high photophysical responsiveness and enzymatic accommodation suggest that the mth N alphabet is a biophysically viable tool and can be used to probe the tolerance of nucleoside/tide-processing enzymes to structural perturbations of their substrates.


Assuntos
RNA , Ribonucleosídeos , Antimetabólitos , Corantes , Nucleosídeos
14.
Sci Rep ; 12(1): 1149, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064200

RESUMO

In biological systems, the synthesis of nucleic acids, such as DNA and RNA, is catalyzed by enzymes in various aqueous solutions. However, substrate specificity is derived from the chemical properties of the residues, which implies that perturbations of the solution environment may cause changes in the fidelity of the reaction. Here, we investigated non-promoter-based synthesis of RNA using T7 RNA polymerase (T7 RNAP) directed by an RNA template in the presence of polyethylene glycol (PEG) of various molecular weights, which can affect polymerization fidelity by altering the solution properties. We found that the mismatch extensions of RNA propagated downstream polymerization. Furthermore, PEG promoted the polymerization of non-complementary ribonucleoside triphosphates, mainly due to the decrease in the dielectric constant of the solution. These results indicate that the mismatch extension of RNA-dependent RNA polymerization by T7 RNAP is driven by the stacking interaction of bases of the primer end and the incorporated nucleotide triphosphates (NTP) rather than base pairing between them. Thus, proteinaceous RNA polymerase may display different substrate specificity with changes in dielectricity caused by molecular crowding conditions, which can result in increased genetic diversity without proteinaceous modification.


Assuntos
RNA Polimerases Dirigidas por DNA/química , RNA/biossíntese , Proteínas Virais/química , Pareamento de Bases , RNA Polimerases Dirigidas por DNA/metabolismo , Variação Genética , Polimerização , RNA/genética , Ribonucleosídeos/química , Ribonucleosídeos/metabolismo , Soluções , Especificidade por Substrato , Proteínas Virais/metabolismo
15.
s.l; CONETEC; 19 ene. 2022.
Não convencional em Espanhol | LILACS, BRISA/RedTESA | ID: biblio-1354072

RESUMO

INTRODUCCIÓN: El molnupiravir (EIDD-2801 o MK-4482-013) es un profármaco de un análogo de ribonucleósido antivírico, que se administra por vía oral, tiene actividad contra el SARS-CoV-2 in vitro, y que se encuentra actualmente bajo investigación para su uso en COVID-19. Actualmente la Administración de Alimentos y Medicamentos de los Estados Unidos (FDA, su sigla del inglés Food and Drug Administration) ha autorizado su comercialización de emergencia, mientras que la Agencia Europea de Medicamentos (EMA, su sigla del inglés European Medicine Agency) y Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) aún no la han autorizado.(17)(18) En Argentina, la provincia de Catamarca comenzó a utilizarlo, cuando gobierno de esta provincia aprobó el uso del molnupiravir en pacientes leves a moderados, con factores de riesgo, convirtiéndose en la primera provincia del país en tomar esta medida.(19) Primeramente, el 4 de noviembre del 2021 la Agencia Reguladora de Medicamentos y Productos Sanitarios de Reino Unido se había convertido en el primer país del Mundo en autorizar su comercialización en personas que tienen COVID-19 de leve a moderado y al menos un factor de riesgo para desarrollar una enfermedad grave (como obesidad, edad avanzada (> 60 años), diabetes mellitus o enfermedades cardíacas). Sin embargo, el Instituto Nacional de Salud y Cuidados de Excelencia del Reino Unido (NICE, su sigla del inglés National Institute for Health and Clinical Excellence) todavía no se ha expedido al respecto. OBJETIVO: El objetivo del presente informe es evaluar parámetros de eficacia, seguridad, conveniencia y recomendaciones disponibles acerca del empleo de molnupiravir para el tratamiento de pacientes con COVID-19 en Argentina. MÉTODOS: Las conclusiones del presente informe se sustentan en el análisis de los siguientes dominios: Efectos en la Salud: Teniendo en cuenta la velocidad con la que la información relacionada a la pandemia aparece y se modifica (link), se desarrolló un protocolo sustentado en proyectos que resume activamente la evidencia científica a medida que la misma se hace disponible. Con este fin se utilizó la plataforma Love de Epistemonikos para identificar revisiones sistemáticas "vivas". Se seleccionaron aquellas con una calidad metodológica apropiada evaluada a través de la herramienta AMSTAR-2, y que a su vez llevaran un proceso de actualización frecuente. De cada una de las revisiones sistemáticas identificadas se extractaron los efectos de la intervención sobre los desenlaces priorizados como importantes o críticos y la certeza en dichos efectos. Para la priorización de los desenlaces se adoptó una perspectiva desde el paciente considerando sus potenciales preferencias. La selección se realizó por consenso entre los autores y supervisores del informe considerando los resultados de múltiples ejercicios de priorización publicados, realizados en el marco del desarrollo de distintas guías de práctica clínica. Implementación: Este dominio contempla dos subdominios: la existencia de barreras y facilitadores en nuestro contexto para la implementación de la tecnología evaluada no consideradas en los otros dominios analizados, y los costos comparativos en relación con otras intervenciones similares. Con el objetivo de emitir un juicio de valor sobre la magnitud de dichos costos, en pacientes hospitalizados se utilizó como comparador al tratamiento con dexametasona, que ha demostrado ser una intervención accesible y de beneficios importantes en el contexto analizado. Recomendaciones: Para la identificación de recomendaciones sustentadas en evidencia y actualizadas, se utilizó la plataforma COVID recmap. Se seleccionaron aquellas guías con rigor metodológico apropiado según la herramienta AGREE II (> 70%) y se incorporaron sus recomendaciones al informe. RESULTADOS: Se identificaron dos revisiones sistemáticas que cumplieron con los criterios de inclusión del presente informe y reportaron resultados. Se identificaron 4 ECA que incluyeron 1.692 pacientes en los que molnupiravir se comparó con el tratamiento estándar en pacientes con COVID-19 o en voluntarios sanos. CONCLUSIONES: El cuerpo de la evidencia muestra que existe incertidumbre en el efecto de molnupiravir sobre la mortalidad (certeza muy baja ⨁◯◯◯). Molnupiravir probablmente reduzca las hospitalizaciones en pacientes con enfermedad leve de reciente comienzo y factores de riesgo para progresión a enfermedad severa. Sin embargo, la magnitud de la reducción solo resulta importante (mayor a 1%) para pacientes sin esquema de vacunación completo o con riesgo de respuesta inmune inapropriada. La tecnología no está autorizada para su comercialización por la Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) de nuestro país al momento de la fecha de realización del presente informe y se encuentra disponible en forma limitada en una sola provincia. Asimismo, el costo comparativo estimado es elevado, más aún teniendo en cuenta la elevada población objetivo a ser tratada. Las guías de práctica clínica basadas en evidencia identificadas realizan recomendaciones condicionales con direcciones opuestas.


Assuntos
Humanos , Ribonucleosídeos/uso terapêutico , Pró-Fármacos/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , COVID-19/tratamento farmacológico , Eficácia , Análise Custo-Benefício
16.
Nucleic Acids Res ; 50(D1): D231-D235, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34893873

RESUMO

The MODOMICS database has been, since 2006, a manually curated and centralized resource, storing and distributing comprehensive information about modified ribonucleosides. Originally, it only contained data on the chemical structures of modified ribonucleosides, their biosynthetic pathways, the location of modified residues in RNA sequences, and RNA-modifying enzymes. Over the years, prompted by the accumulation of new knowledge and new types of data, it has been updated with new information and functionalities. In this new release, we have created a catalog of RNA modifications linked to human diseases, e.g., due to mutations in genes encoding modification enzymes. MODOMICS has been linked extensively to RCSB Protein Data Bank, and sequences of experimentally determined RNA structures with modified residues have been added. This expansion was accompanied by including nucleotide 5'-monophosphate residues. We redesigned the web interface and upgraded the database backend. In addition, a search engine for chemically similar modified residues has been included that can be queried by SMILES codes or by drawing chemical molecules. Finally, previously available datasets of modified residues, biosynthetic pathways, and RNA-modifying enzymes have been updated. Overall, we provide users with a new, enhanced, and restyled tool for research on RNA modification. MODOMICS is available at https://iimcb.genesilico.pl/modomics/.


Assuntos
Bases de Dados de Ácidos Nucleicos , Enzimas/genética , RNA/genética , Ribonucleosídeos/genética , Interface Usuário-Computador , Sequência de Bases , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Gráficos por Computador , Bases de Dados de Proteínas , Conjuntos de Dados como Assunto , Enzimas/metabolismo , Gastroenteropatias/genética , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Doenças Hematológicas/genética , Doenças Hematológicas/metabolismo , Doenças Hematológicas/patologia , Humanos , Internet , Transtornos Mentais/genética , Transtornos Mentais/metabolismo , Transtornos Mentais/patologia , Doenças Musculoesqueléticas/genética , Doenças Musculoesqueléticas/metabolismo , Doenças Musculoesqueléticas/patologia , Mutação , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , RNA/metabolismo , Processamento Pós-Transcricional do RNA , Ribonucleosídeos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
17.
Chembiochem ; 23(3): e202100601, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34821449

RESUMO

Development of versatile probes that can enable the study of different conformations and recognition properties of therapeutic nucleic acid motifs by complementing biophysical techniques can greatly aid nucleic acid analysis and therapy. Here, we report the design, synthesis and incorporation of an environment-sensitive ribonucleoside analogue, which serves as a two-channel biophysical platform to investigate RNA structure and recognition by fluorescence and 19 F NMR spectroscopy techniques. The nucleoside analogue is based on a 5-fluorobenzofuran-uracil core and its fluorescence and 19 F NMR chemical shifts are highly sensitive to changes in solvent polarity and viscosity. Notably, the modified ribonucleotide and phosphoramidite substrates can be efficiently incorporated into RNA oligonucleotides (ONs) by in vitro transcription and standard solid-phase ON synthesis protocol, respectively. Fluorescence and 19 F readouts of the nucleoside incorporated into model RNA ONs are sensitive to the neighbouring base environment. The responsiveness of the probe was aptly utilized in detecting and quantifying the metal ion-induced conformational change in an internal ribosome entry site RNA motif of hepatitis C virus, which is an important therapeutic target. Taken together, our probe is a good addition to the nucleic acid analysis toolbox with the advantage that it can be used to study nucleic acid conformation and recognition simultaneously by two biophysical techniques.


Assuntos
Fluorescência , RNA Viral/análise , Ribonucleosídeos/química , Flúor , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ribonucleosídeos/síntese química
18.
Methods Mol Biol ; 2404: 167-188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34694609

RESUMO

During post-transcriptional gene regulation (PTGR), RNA binding proteins (RBPs) interact with all classes of RNA to control RNA maturation, stability, transport, and translation. Here, we describe Photoactivatable-Ribonucleoside-Enhanced Crosslinking and Immunoprecipitation (PAR-CLIP), a transcriptome-scale method for identifying RBP binding sites on target RNAs with nucleotide-level resolution. This method is readily applicable to any protein directly contacting RNA, including RBPs that are predicted to bind in a sequence- or structure-dependent manner at discrete RNA recognition elements (RREs), and those that are thought to bind transiently, such as RNA polymerases or helicases.


Assuntos
Transcriptoma , Sítios de Ligação , Imunoprecipitação , Ligação Proteica , RNA/genética , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleosídeos
19.
Lipids Health Dis ; 20(1): 151, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34727932

RESUMO

BACKGROUND: Acylcarnitine is an intermediate product of fatty acid oxidation. It is reported to be closely associated with the occurrence of diabetic cardiomyopathy (DCM). However, the mechanism of acylcarnitine affecting myocardial disorders is yet to be explored. This current research explores the different chain lengths of acylcarnitines as biomarkers for the early diagnosis of DCM and the mechanism of acylcarnitines for the development of DCM in-vitro. METHODS: In a retrospective non-interventional study, 50 simple type 2 diabetes mellitus patients and 50 DCM patients were recruited. Plasma samples from both groups were analyzed by high throughput metabolomics and cluster heat map using mass spectrometry. Principal component analysis was used to compare the changes occurring in the studied 25 acylcarnitines. Multivariable binary logistic regression was used to analyze the odds ratio of each group for factors and the 95% confidence interval in DCM. Myristoylcarnitine (C14) exogenous intervention was given to H9c2 cells to verify the expression of lipid metabolism-related protein, inflammation-related protein expression, apoptosis-related protein expression, and cardiomyocyte hypertrophy and fibrosis-related protein expression. RESULTS: Factor 1 (C14, lauroylcarnitine, tetradecanoyldiacylcarnitine, 3-hydroxyl-tetradecanoylcarnitine, arachidic carnitine, octadecanoylcarnitine, 3-hydroxypalmitoleylcarnitine) and factor 4 (octanoylcarnitine, hexanoylcarnitine, decanoylcarnitine) were positively correlated with the risk of DCM. Exogenous C14 supplementation to cardiomyocytes led to increased lipid deposition in cardiomyocytes along with the obstacles in adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathways and affecting fatty acid oxidation. This further caused myocardial lipotoxicity, ultimately leading to cardiomyocyte hypertrophy, fibrotic remodeling, and increased apoptosis. However, this effect was mitigated by the AMPK agonist acadesine. CONCLUSIONS: The increased plasma levels in medium and long-chain acylcarnitine extracted from factors 1 and 4 are closely related to the risk of DCM, indicating that these factors can be an important tool for DCM risk assessment. C14 supplementation associated lipid accumulation by inhibiting the AMPK/ACC/CPT1 signaling pathway, aggravated myocardial lipotoxicity, increased apoptosis apart from cardiomyocyte hypertrophy and fibrosis were alleviated by the acadesine.


Assuntos
Carnitina/análogos & derivados , Diabetes Mellitus Tipo 2/complicações , Cardiomiopatias Diabéticas/metabolismo , Metabolismo dos Lipídeos , Adulto , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Biomarcadores/sangue , Carnitina/sangue , Carnitina/química , Carnitina/farmacologia , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Mioblastos Cardíacos/efeitos dos fármacos , Mioblastos Cardíacos/metabolismo , Ácidos Mirísticos/farmacologia , Ratos , Estudos Retrospectivos , Ribonucleosídeos/farmacologia , Fatores de Risco
20.
Bioorg Med Chem Lett ; 54: 128439, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34748937

RESUMO

O2-Phosphodiesterification of xanthosine has been achieved by a one-pot procedure consisting of the phosphitylation of the 2-carbonyl group of appropriately protected xanthosine derivatives using phosphoramidites and N-(cyanomethyl)dimethylammonium triflate (CMMT), oxidation of the resulting xanthosine 2-phosphite triesters, and deprotection. In addition, a study on the hydrolytic stability of a fully deprotected xanthosine 2-phosphate diester has revealed that it is more stable at higher pH.


Assuntos
Ésteres/síntese química , Organofosfatos/síntese química , Ribonucleosídeos/síntese química , Xantinas/síntese química , Ésteres/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Organofosfatos/química , Fosforilação , Ribonucleosídeos/química , Xantinas/química
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