Development of [18F]DASA-10 for enhanced imaging of pyruvate kinase M2.

PURPOSE: The aim of this study was to develop a positron emission tomography (PET) radiotracer for measuring pyruvate kinase M2 (PKM2) with improved physicochemical and pharmacokinetic properties compared to [18F]DASA-23. EXPERIMENTAL DESIGN: First, we synthesized [18F]DASA-10 and tested its uptake and retention compared to [18F]DASA-23 in human and mouse glioma cell lines. We then confirmed the specificity of [18F]DASA-10 by transiently modulating the expression of PKM2 in DU145 and HeLa cells. Next, we determined [18F]DASA-10 pharmacokinetics in healthy nude mice using PET imaging and subsequently assessed the ability of [18F]DASA-10 versus [18F]DASA-23 to enable in vivo detection of intracranial gliomas in syngeneic C6 rat models of glioma. RESULTS: [18F]DASA-10 demonstrated excellent cellular uptake and retention with values significantly higher than [18F]DASA-23 in all cell lines and timepoints investigated. [18F]DASA-10 showed a 73 % and 65 % reduced uptake respectively in DU145 and HeLa cells treated with PKM2 siRNA as compared to control siRNA treated cells. [18F]DASA-10 showed favorable biodistribution and pharmacokinetic properties and a significantly improved tumor-to-brain ratio in rat C6 glioma models relative to [18F]DASA-23 (3.2 ± 0.8 versus 1.6 ± 0.3, p = 0.01). CONCLUSION: [18F]DASA-10 is a new PET radiotracer for molecular imaging of PKM2 with potential to overcome the prior limitations observed with [18F]DASA-23. [18F]DASA-10 shows promise for clinical translation to enable imaging of brain malignancies owing to its low background signal in the healthy brain.

Engineering Lipid Nanoparticles for Enhanced Intracellular Delivery of mRNA through Inhalation.

Despite lipid nanoparticles' (LNPs) success in the effective and safe delivery of mRNA vaccines, an inhalation-based mRNA therapy for lung diseases remains challenging. LNPs tend to disintegrate due to shear stress during aerosolization, leading to ineffective delivery. Therefore, LNPs need to remain stable through the process of nebulization and mucus penetration, yet labile enough for endosomal escape. To meet these opposing needs, we utilized PEG lipid to enhance the surficial stability of LNPs with the inclusion of a cholesterol analog, ß-sitosterol, to improve endosomal escape. Increased PEG concentrations in LNPs enhanced the shear resistance and mucus penetration, while ß-sitosterol provided LNPs with a polyhedral shape, facilitating endosomal escape. The optimized LNPs exhibited a uniform particle distribution, a polyhedral morphology, and a rapid mucosal diffusion with enhanced gene transfection. Inhaled LNPs led to localized protein production in the mouse lung without pulmonary or systemic toxicity. Repeated administration of these LNPs led to sustained protein production in the lungs. Lastly, mRNA encoding the cystic fibrosis transmembrane conductance regulator (CFTR) was delivered after nebulization to a CFTR-deficient animal model, resulting in the pulmonary expression of this therapeutic protein. This study demonstrated the rational design approach for clinical translation of inhalable LNP-based mRNA therapies.

Prevalencia de las alteraciones de la movilidad cervical en los estudiantes de una universidad

Resumen La movilidad articular se conoce como la capacidad de movimiento de una articulación en conjunto con los diferentes grupos musculares. En el dolor cervical o cervicalgia, esta se puede ver alterada por varios factores como: el dolor, la debilidad muscular y la limitación. Objetivos : Determinar las alteraciones de la movilidad cervical en los estudiantes de 1er a 3er ciclo de la Carrera de Fisioterapia de la Universidad Católica de Santiago de Guayaquil. Metodología : Estudio de enfoque cuantitativo y alcance descriptivo de diseño no experimental de tipo transversal en 106 estudiantes, considerando los criterios de inclusión se utilizó el IDC y el Test de Flexión Cráneo-Cervical. Resultados : De la muestra conformada por 100%(106) estudiantes; utilizando el Índice de Discapacidad Cervical se pudo evidenciar que el 55% de la población entra en el rango de sin discapacidad, en comparación con el porcentaje sobrante que equivale a un 38% y 7% entran en el rango de discapacidad leve y discapacidad moderada respectivamente, en relación a la evaluación de la movilidad articular mediante el Test de Flexión Cráneo-Cervical el 79% presentó alteración y un 21% el valor normal, en la evaluación con el instrumento Stabilizer Pressure Biofeedback el 75% presentó alteración de la fuerza muscular y el 25 % el valor normal. Conclusiones : Entre los estudiantes de 1ro y 3er ciclo de la carrera de Fisioterapia de la Universidad Católica de Santiago de Guayaquil se determinó que existe un alto porcentaje en relación a las alteraciones de la movilidad cervical.

Abstract Joint mobility is known as the ability to move a joint in conjunction with the different muscle groups. In cervical pain or neck pain, this can be altered by several factors such as: pain, muscle weakness and limitation. Objective : To determine the alterations of cervical mobility in students from 1st to 3rd cycle of the Physiotherapy Career of the Catholic University of Santiago de Guayaquil. Methodology : Study with a quantitative approach and descriptive scope of a non-experimental cross-sectional design in 106 students, considering the inclusion criteria, the IDC and the Cranio-Cervical Flexion Test were used. Results : From the sample made up of 100% (106) students; Using the Cervical Disability Index, it was possible to show that 55% of the population falls into the range of without disability, compared to the excess percentage that is equivalent to 38% and 7%, they fall into the range of mild disability and moderate disability respectively. In relation to the evaluation of joint mobility using the Cranio-Cervical Flexion Test, 79% presented alteration and 21% the normal value, in the evaluation with the Stabilizer Pressure Biofeedback instrument, 75% presented alteration of muscle strength and 25% the normal value. Conclusions : Among the students of the 1st and 3rd cycle of the Physiotherapy career at the Catholic University of Santiago de Guayaquil, it was determined that there is a high percentage in relation to cervical mobility alterations.

Resumo A mobilidade articular é conhecida como a capacidade de mover uma articulação em conjunto com os diferentes grupos musculares. Na cervicalgia ou cervicalgia, isso pode ser alterado por vários fatores, tais como: dor, fraqueza muscular e limitação. Objetivo : Determinar as alterações da mobilidade cervical em alunos do 1º ao 3º ciclo da Carreira de Fisioterapia da Universidade Católica de Santiago de Guayaquil. Metodologia : Estudo com abordagem quantitativa e escopo descritivo de delineamento transversal não experimental em 106 alunos, considerando os critérios de inclusão, foram utilizados o IDC e o Teste de Flexão Crânio-Cervical. Resultados : Da amostra composta por 100% (106) alunos; Utilizando o Índice de Incapacidade Cervical, foi possível evidenciar que 55% da população se enquadra na faixa de sem incapacidade, em comparação ao percentual excedente que equivale a 38% e 7%, se enquadra na faixa de incapacidade leve e moderada Em relação à avaliação da mobilidade articular através do Teste de Flexão Crânio-Cervical, 79% apresentaram alteração e 21% o valor normal; na avaliação com o instrumento Estabilizador de Pressão Biofeedback, 75% apresentaram alteração da força muscular e 25% o valor normal. Conclusão : Entre os alunos do 1º e 3º ciclo da carreira de Fisioterapia da Universidade Católica de Santiago de Guayaquil, constatou-se que há um alto percentual em relação às alterações da mobilidade cervical.

SliC is a surface-displayed lipoprotein that is required for the anti-lysozyme strategy during Neisseria gonorrhoeae infection.

Lysozymes are nearly omnipresent as the first line of immune defense against microbes in animals. They exert bactericidal action through antimicrobial peptide activity and peptidoglycan hydrolysis. Gram-negative bacteria developed several weapons to battle lysozymes, including inhibitors of c-type lysozymes in the MliC/PliC family and the Neisseria adhesin complex protein (ACP). Until the recent discovery of ACP, no proteinaceous lysozyme inhibitors were reported for the genus Neisseria, including the important human pathogen N. gonorrhoeae. Here, we describe a previously unrecognized gonococcal virulence mechanism involving a protein encoded by the open reading frame ngo1063 that acts to counteract c-type Iysozyme and provides a competitive advantage in the murine model of gonorrhea. We named this protein SliC as a surface-exposed lysozyme inhibitor of c-type lysozyme. SliC displays low overall primary sequence similarity to the MliC/PliC inhibitors, but we demonstrate that it has a parallel inhibitory mechanism. Our studies provide the first evidence that bacterial proteinaceous lysozyme inhibitors protect against host lysozyme during infection based on lack of attenuation of the ΔsliC mutant in lysozyme knock-out mice, and that the conserved residues involved in lysozyme inhibition, S83 and K103, are functionally indispensable during infection in wild type mice. Recombinant SliC completely abrogated the lytic activity of human and chicken c-type lysozymes, showing a preference towards human lysozyme with an IC50 of 1.85 µM and calculated KD value of 9.2 ± 1.9 µM. In contrast, mutated SliC bearing S83A and K103A substitutions failed to protect fluorescein-labeled cell-wall from lysozyme-mediated hydrolysis. Further, we present data revealing that SliC is a surface-displayed lipoprotein released in membrane vesicles that is expressed throughout all phases of growth, in conditions relevant to different niches of the human host, and during experimental infection of the murine genital tract. SliC is also highly conserved and expressed by diverse gonococcal isolates as well as N. meningitidis, N. lactamica, and N. weaveri. This study is the first to highlight the importance of an anti-lysozyme strategy to escape the innate immune response during N. gonorrhoeae infection.