Enhancing Neuronal Cell Uptake of Therapeutic Nucleic Acids with Tetrahedral DNA Nanostructures.

The successful translation of therapeutic nucleic acids (NAs) for the treatment of neurological disorders depends on their safe and efficient delivery to neural cells, in particular neurons. DNA nanostructures can be a promising NAs delivery vehicle. Nonetheless, the potential of DNA nanostructures for neuronal cell delivery of therapeutic NAs is unexplored. Here, tetrahedral DNA nanostructures (TDN) as siRNA delivery scaffolds to neuronal cells, exploring the influence of functionalization with two different reported neuronal targeting ligands: C4-3 RNA aptamer and Tet1 peptide are investigated. Nanostructures are characterized in vitro, as well as in silico using molecular dynamic simulations to better understand the overall TDN structural stability. Enhancement of neuronal cell uptake of TDN functionalized with the C4-3 Aptamer (TDN-Apt), not only in neuronal cell lines but also in primary neuronal cell cultures is demonstrated. Additionally, TDN and TDN-Apt nanostructures carrying siRNA are shown to promote silencing in a process aided by chloroquine-induced endosomal disruption. This work presents a thorough workflow for the structural and functional characterization of the proposed TDN as a nano-scaffold for neuronal delivery of therapeutic NAs and for targeting ligands evaluation, contributing to the future development of new neuronal drug delivery systems based on DNA nanostructures.

Rewired glycosylation activity promotes scarless regeneration and functional recovery in spiny mice after complete spinal cord transection.

Regeneration of adult mammalian central nervous system (CNS) axons is abortive, resulting in inability to recover function after CNS lesion, including spinal cord injury (SCI). Here, we show that the spiny mouse (Acomys) is an exception to other mammals, being capable of spontaneous and fast restoration of function after severe SCI, re-establishing hind limb coordination. Remarkably, Acomys assembles a scarless pro-regenerative tissue at the injury site, providing a unique structural continuity of the initial spinal cord geometry. The Acomys SCI site shows robust axon regeneration of multiple tracts, synapse formation, and electrophysiological signal propagation. Transcriptomic analysis of the spinal cord following transcriptome reconstruction revealed that Acomys rewires glycosylation biosynthetic pathways, culminating in a specific pro-regenerative proteoglycan signature at SCI site. Our work uncovers that a glycosylation switch is critical for axon regeneration after SCI and identifies ß3gnt7, a crucial enzyme of keratan sulfate biosynthesis, as an enhancer of axon growth.

Obstructive Sleep Apnea Screening with a 4-Item Instrument, Named GOAL Questionnaire: Development, Validation and Comparative Study with No-Apnea, STOP-Bang, and NoSAS.

BACKGROUND: Obstructive sleep apnea (OSA) is a very prevalent disorder. Here, we aimed to develop and validate a practical questionnaire with yes-or-no answers, and to compare its performance with other well-validated instruments: No-Apnea, STOP-Bang, and NoSAS. METHODS: A cross-sectional study containing consecutively selected sleep-lab subjects underwent full polysomnography. A 4-item model, named GOAL questionnaire (gender, obesity, age, and loud snoring), was developed and subsequently validated, with item-scoring of 0-4 points (≥2 points indicating high risk for OSA). Discrimination was assessed by area under the curve (AUC), while predictive parameters were calculated using contingency tables. OSA severity was classified based on conventionally accepted apnea/hypopnea index thresholds: ≥5.0/h (OSA≥5), ≥15.0/h (OSA≥15), and ≥30.0/h (OSA≥30). RESULTS: Overall, 7377 adults were grouped into two large and independent cohorts: derivation (n = 3771) and validation (n = 3606). In the derivation cohort, screening of OSA≥5, OSA≥15, and OSA≥30 revealed that GOAL questionnaire achieved sensitivity ranging from 83.3% to 94.0% and specificity ranging from 62.4% to 38.5%. In the validation cohort, screening of OSA≥5, OSA≥15, and OSA≥30, corroborated validation steps with sensitivity ranging from 83.7% to 94.2% and specificity from 63.4% to 37.7%. In both cohorts, discriminatory ability of GOAL questionnaire for screening of OSA≥5, OSA≥15, and OSA≥30 was similar to No-Apnea, STOP-Bang or NoSAS. CONCLUSION: All four instruments had similar performance, leading to a possible greater practical implementation of the GOAL questionnaire, a simple instrument with only four parameters easily obtained during clinical evaluation.

Risk Factors and Outcomes of Tetralogy of Fallot: From Fetal to Neonatal Life.

Tetralogy of Fallot (ToF) is the most prevalent cyanotic congenital heart disease. Genetic syndromes are present in up to one quarter of patients with this condition, leading to increased morbidity and mortality. Our aim in this work is to characterize our population, evaluate ToF based on the presence of genotype anomalies, and investigate early intervention predictors and outcomes. A retrospective study was performed on neonates with ToF born between August 1, 2008, and August 31, 2018, and admitted to a level III neonatal intensive care unit (NICU). Patients were categorized based on the presence of genotype anomalies and timing of intervention. Thirty-nine neonates were included. The overall mortality during the follow-up period was 5.1% (n = 2). Threatened preterm labor/preterm labor was more prevalent in patients with associated genotype anomalies (p = 0.015). Multivariate analysis showed an association between an abnormal amount of amniotic fluid and ToF with altered genotype, adjusted for smoking, maternal age, gestational age and birth weight [OR = 29.92, 95% CI (1.35-662.44), p = 0.032]. We also found an association between cesarean delivery and neonatal procedures (p = 0.006). Mortality was significantly higher in neonates who underwent early intervention (p = 0.038). Our results indicate that an abnormal amount of amniotic fluid is an independent predictive factor for ToF with genotype alterations. This finding could ultimately have an impact on both prenatal and neonatal counseling and management.

Diaqua-(6-bromo-picolinato-κN,O)(nitrato-κO,O)copper(II).

In the monomeric title complex, [Cu(C(6)H(3)BrNO(2))(NO(3))(H(2)O)(2)], the Cu(II) ion is coordinated by a bidentate 6-bromo-picolinate ion, one nitrate ion and two water mol-ecules in a geometry inter-mediate between five- and six-coordinate. Conventional O-H⋯O hydrogen bonds link the complex mol-ecules, forming layers parallel to the ab plane.

Synthesis of ATP derivatives of compounds of the mevalonate pathway (isopentenyl di- and triphosphate; geranyl di- and triphosphate, farnesyl di- and triphosphate, and dimethylallyl diphosphate) catalyzed by T4 RNA ligase, T4 DNA ligase and other ligases Potential relationship with the effect of bisphosphonates on osteoclasts.

Compounds of the mevalonate pathway containing a terminal di- or triphosphate (mev-PP or mev-PPP) were tested as substrates of several enzyme ligases (T4 RNA ligase, T4 DNA ligase, firefly luciferase and other ligases) for the synthesis of ATP derivatives of the mev-pppA or mev-ppppA type. T4 RNA ligase, in the presence of ATP and the substrates: geranyl, farnesyl or isopentenyl triphosphates, and geranyl, farnesyl, dimethylallyl or isopentenyl diphosphates, all at 0.3 mM concentration, catalyzed the synthesis of the corresponding ATP derivatives at a relative rate of activity of: 7.6+/-1.4 mU/mg or 100%; 39%; 42%; 24%; 18%; 12% and 6%, respectively. Inhibition (%) of the synthesis by excess of substrate (0.8 mM vs. 0.3 mM) was observed with farnesyl diphosphate (99%); farnesyl triphosphate (96%) and geranyl triphosphate (32%). V(max), K(m), K(cat) and K(cat)/K(m) values were also determined. The K(cat)/K(m) values calculated were for: farnesyl triphosphate, 166; geranyl triphosphate, 52.2; farnesyl diphosphate, 12.1; geranyl diphosphate, 8.6; isopentenyl triphosphate, 6.7; dimethylallyl diphosphate, 3.1 and isopentenyl diphosphate, 0.9. Similar results were obtained with T4 DNA ligase. The above-mentioned compounds were also substrates of firefly luciferase synthesizing the mev-pppA or mev-ppppA derivatives. In our hands, neither the acyl- or acetyl-CoA synthetases nor the ubiquiting activating enzyme (E1) catalyzed the synthesis of ATP derivatives of these compounds. The results here presented could be related with the mechanism of action of bisphosphonates on osteoclasts or tumor cells.

N,N'-Bis-[(E)-(6-methyl-2-pyridyl)-methyl-ene]hexane-1,6-diamine.

The title compound, C(20)H(26)N(4), is composed of two (6-methyl-2-pyridyl)methyl-ene units linked by a 1,6-diamine hexane chain. The mol-ecule has C(i) symmetry with the inversion center situated at the mid-point of the central C-C bond. The alkyl chain has an all-trans conformation, with all the non-H atoms sharing the same plane [maximum deviation 0.004 (3) Å]. The pyridylmethyl-ene groups are also planar [maximum deviation 0.009 (3) Å], making an angle of 53.78 (19)° with the hexane chain plane. In the crystal, the mol-ecules assemble in layers, stacking along the a axis. The stacks are hold together by attractive interactions between π electron systems.

Bis[(2-quinol-yl)methane-diol-κN,O](sulfato-κO)copper(II) dihydrate.

In the title compound, [Cu(SO(4))(C(10)H(9)NO(2))(2)]·2H(2)O, the Cu(II) ion is chelated by two (2-quinol-yl)methane-diol ligands and coordinated by a monodentate sulfate ligand in a distorted trigonal-bipyramidal environment, with O atoms occupying the equatorial sites and N atoms in the axial sites. The dihedral angle between the two essentially planar quinoline ring systems is 45.02 (9)°. In the crystal structure, an extensive O-H⋯O hydrogen-bonding network forms layers parallel to the ab plane.

4-Amino-3,5-di-2-pyridyl-4H-1,2,4-triazole.

In the crystal structure of the title compound, C(12)H(10)N(6), the mol-ecules deviate slightly from planarity. The plane of the central triazole ring makes angles of 6.13 (9) and 3.28 (10)° with the pyridyl ring planes. Intra-molecular N-H⋯N inter-actions form six-membered closed rings. The crystal packing also shows weak C-H⋯π and C-H⋯N inter-actions.

(Benzoato-κO,O')(quinoline-2-carboxyl-ato-κN,O)(quinoline-2-carboxylic acid-κN,O)copper(II).

The crystal structure of the title compound, [Cu(C(10)H(6)NO(2))(C(7)H(5)O(2))(C(10)H(7)NO(2))], contains copper(II) ions five-coordinated in a distorted trigonal-bipyramidal environment. The equatorial plane is occupied by three O atoms, one from the carboxyl-ate group of the benzoate ion considered as occupying a single coordination site, the other two from two carboxyl-ate groups of the quinaldic acid and quinaldate ligands. The axial positions are occupied by the N atoms of the quinoline ring system. The metal ion lies on a twofold axis that bisects the benzoate ion. The quinaldate and quinaldic acid ligands are equivalent by symmetry, and the carboxyl-ate/carboxyl groups are disordered. The disordered H atom is shared between the carboxyl-ate groups of adjacent quinaldic acid mol-ecules. Such hydrogen bonds delineate zigzag chains that run along the c axis. The structure is very similar to that of the Mn(II) analog.

(Benzoato-κO,O')(quinoline-2-carboxyl-ato-κN,O)(quinoline-2-carboxylic acid-κN,O)manganese(II).

The crystal structure of the title compound, [Mn(C(7)H(5)O(2))(C(10)H(6)NO(2))(C(10)H(7)NO(2))], contains manganese(II) ions six-coordinated in a distorted octa-hedral environment. The equatorial plane is occupied by four O atoms, two from the carboxyl-ate group of the benzoate ion, the other two from carboxyl-ate/carboxyl groups of the quinaldate/quinaldic acid mol-ecules. The axial positions are occupied by the N atoms of the quinoline ring systems. The metal ion lies on a twofold rotation axis that bisects the benzoate ligand; the quinaldate and quinaldic acid ligands are therefore equivalent by symmetry, and the carboxylate/carboxyl groups are disordered. The complexes are joined together by hydrogen bonds between the carboxyl-ate/carboxyl groups of adjacent quinaldate/quinaldic acid mol-ecules, forming zigzag chains that run along the c axis.