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1.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612662

RESUMO

In this study, a new micro delivery system based on an anionic methacrylate copolymer, able to improve the biological response of myo-inositol by daily oral administration, was manufactured by spray-drying. It has an ideal dose form for oral administration, with an experimental drug loading (DL)% of 14% and a regulated particle size of less than 15 µm. The new formulation features an improvement on traditional formulations used as a chronic therapy for the treatment of polycystic ovary syndrome. The microparticles' release profile was studied and ex vivo porcine intestinal mucosa permeation experiments were performed to predict potential improvements in oral absorption. Batch n. 3, with the higher Eudragit/MI weight ratio (ratio = 6), showed the best-modified release profiles of the active ingredient, ensuring the lowest myo-inositol loss in an acidic environment. The in vivo evaluation of the myo-inositol micro delivery system was carried out in a rat animal model to demonstrate that the bioavailability of myo-inositol was increased when compared to the administration of the same dosage of the pure active ingredient. The AUC and Cmax of the loaded active molecule in the micro delivery system was improved by a minimum of 1.5 times when compared with the pure substance, administered with same dosage and route. Finally, the increase of myo-inositol levels in the ovary follicles was assessed to confirm that a daily administration of the new formulation improves myo-inositol concentration at the site of action, resulting in an improvement of about 1.25 times for the single administration and 1.66 times after 7 days of repeated administration when compared to pure MI.


Assuntos
Micropartículas Derivadas de Células , Metacrilatos , Feminino , Animais , Ratos , Suínos , Disponibilidade Biológica , Administração Oral , Comércio , Polímeros
2.
Circ Res ; 121(5): 525-536, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28620067

RESUMO

RATIONALE: Mutations in the cardiac Ryanodine Receptor gene (RYR2) cause dominant catecholaminergic polymorphic ventricular tachycardia (CPVT), a leading cause of sudden death in apparently healthy individuals exposed to emotions or physical exercise. OBJECTIVE: We investigated the efficacy of allele-specific silencing by RNA interference to prevent CPVT phenotypic manifestations in our dominant CPVT mice model carriers of the heterozygous mutation R4496C in RYR2. METHODS AND RESULTS: We developed an in vitro mRNA and protein-based assays to screen multiple siRNAs for their ability to selectively silence mutant RYR2-R4496C mRNA over the corresponding wild-type allele. For the most performant of these siRNAs (siRYR2-U10), we evaluated the efficacy of an adeno-associated serotype 9 viral vector (AAV9) expressing miRYR2-U10 in correcting RyR2 (Ryanodine Receptor type 2 protein) function after in vivo delivery by intraperitoneal injection in neonatal and adult RyR2R4496C/+ (mice heterozygous for the R4496C mutation in the RyR2) heterozygous CPVT mice. Transcriptional analysis showed that after treatment with miRYR2-U10, the ratio between wild-type and mutant RYR2 mRNA was doubled (from 1:1 to 2:1) confirming the ability of miRYR2-U10 to selectively inhibit RYR2-R4496C mRNA, whereas protein quantification showed that total RyR2 was reduced by 15% in the heart of treated mice. Furthermore, AAV9-miRYR2-U10 effectively (1) reduced isoproterenol-induced delayed afterdepolarizations and triggered activity in infected cells, (2) reduced adrenergically mediated ventricular tachycardia in treated mice, (3) reverted ultrastructural abnormalities of junctional sarcoplasmic reticulum and transverse tubules, and (4) attenuated mitochondrial abnormalities. CONCLUSIONS: The study demonstrates that allele-specific silencing with miRYR2-U10 prevents life-threatening arrhythmias in CPVT mice, suggesting that the reduction of mutant RyR2 may be a novel therapeutic approach for CPVT.


Assuntos
Alelos , Arritmias Cardíacas/genética , Heterozigoto , Mutação/genética , RNA Mensageiro/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Animais , Animais Recém-Nascidos , Arritmias Cardíacas/patologia , Arritmias Cardíacas/prevenção & controle , Células Cultivadas , Inativação Gênica/fisiologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , RNA Mensageiro/ultraestrutura , Canal de Liberação de Cálcio do Receptor de Rianodina/deficiência , Canal de Liberação de Cálcio do Receptor de Rianodina/ultraestrutura
3.
PeerJ ; 4: e1864, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27069803

RESUMO

Several investigations document altered emotion processing in opiate addiction. Nevertheless, the origin of this phenomenon remains unclear. Here we examined the role of alexithymia in the ability (i.e., number of errors-accuracy and reaction times-RTs) of thirty-one heroin addicts and thirty-one healthy controls to detect several affective expressions. Results show generally lower accuracy and higher RTs in the recognition of facial expressions of emotions for patients, compared to controls. The hierarchical multivariate regression analysis shows that alexithymia might be responsible of the between groups difference with respect to the RTs in emotion detection. Overall, we provide new insights in the clinical interpretation of affective deficits in heroin addicts suggesting a role of alexithymia in their ability to recognize emotions.

4.
Indian J Psychol Med ; 36(3): 304-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25035557

RESUMO

BACKGROUND: Internet addiction (IAD) is one of the most diffuse mental disorders among adolescents. AIMS: The aim of our study was to evaluate the relationships between shame, self-efficacy and Internet addiction. MATERIALS AND METHODS: We recruited a total of 670 college students (males = 164, 24.5%; females = 506, 75.5%). The subjects were aged between 18 and 36 years (M = 20.93, SD = 2.52; males: M = 21.43, SD = 2.95; females: M = 20.76, SD = 2.35). We administered the following instruments: Experience of Shame Scale; Perceived Social Self-Efficacy Scale - Adult Version; Perceived Self-Efficacy in Handling Negative Emotions Scales; Internet Addiction Test. STATISTICS ANALYSIS: We applied multivariate analyses of variance (MANOVA), Pearson's correlation indices and linear regression analysis. RESULTS AND CONCLUSION: We found a significant inter-relation between Internet addiction and shame. Shame could be a good predictor of Internet addiction.

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