Enantiospecificity in NMR enabled by chirality-induced spin selectivity.

Spin polarization in chiral molecules is a magnetic molecular response associated with electron transport and enantioselective bond polarization that occurs even in the absence of an external magnetic field. An unexpected finding by Santos and co-workers reported enantiospecific NMR responses in solid-state cross-polarization (CP) experiments, suggesting a possible additional contribution to the indirect nuclear spin-spin coupling in chiral molecules induced by bond polarization in the presence of spin-orbit coupling. Herein we provide a theoretical treatment for this phenomenon, presenting an effective spin-Hamiltonian for helical molecules like DNA and density functional theory (DFT) results on amino acids that confirm the dependence of J-couplings on the choice of enantiomer. The connection between nuclear spin dynamics and chirality could offer insights for molecular sensing and quantum information sciences. These results establish NMR as a potential tool for chiral discrimination without external agents.

iPSC modeling of young-onset Parkinson's disease reveals a molecular signature of disease and novel therapeutic candidates.

Young-onset Parkinson's disease (YOPD), defined by onset at <50 years, accounts for approximately 10% of all Parkinson's disease cases and, while some cases are associated with known genetic mutations, most are not. Here induced pluripotent stem cells were generated from control individuals and from patients with YOPD with no known mutations. Following differentiation into cultures containing dopamine neurons, induced pluripotent stem cells from patients with YOPD showed increased accumulation of soluble α-synuclein protein and phosphorylated protein kinase Cα, as well as reduced abundance of lysosomal membrane proteins such as LAMP1. Testing activators of lysosomal function showed that specific phorbol esters, such as PEP005, reduced α-synuclein and phosphorylated protein kinase Cα levels while increasing LAMP1 abundance. Interestingly, the reduction in α-synuclein occurred through proteasomal degradation. PEP005 delivery to mouse striatum also decreased α-synuclein production in vivo. Induced pluripotent stem cell-derived dopaminergic cultures reveal a signature in patients with YOPD who have no known Parkinson's disease-related mutations, suggesting that there might be other genetic contributions to this disorder. This signature was normalized by specific phorbol esters, making them promising therapeutic candidates.

[Prolonged neurologic deficiency after accidental spinal anesthesia]. / Déficit neurológico prolongado tras anestesia espinal accidental.

A case of severe prolonged neurological deficit following inadvertent spinal anesthesia is presented. Intradural block occurred after a test dose of Bupivacaine and vasoconstrictor when inserting an epidural catheter for post-thoracotomy pain-relief treatment. The likely triggering and etiological factors responsible for the neurological damage after spinal anesthesia were studied and evaluated, mainly those toxic and traumatic. Special mention of the local anesthetics and sodium bisulfite used is made. Preventive measures for this sort of complication are suggested.

BICULTIVO EN BIOFLOC DE CACHAMA BLANCA -Piaractus brachypomus-Y TILAPIA NILÒTICA -Oreochromis niloticus- ALIMENTADAS CON DIETAS DE ORIGEN VEGETAL / CACHAMA -Piaractus brachypomus- AND NILE TILAPIA -Oreochromis niloticus- BICULTURE IN BIOFLOC FED DIETS OF VEGETABLE ORIGIN

Se evaluó el desempeño productivo de cachama blanca y tilapia nilótica cultivadas en biofloc y alimentadas con dietas de origen vegetal. Se cultivaron 80 peces/m³ en proporción 1:1 (cachama : tilapia), con tres niveles de proteína bruta (PB): 16% (T16), 24% (T24) y 32% (T32), en tanques de 1.000 l, con aireación permanente durante 120 días. Se estimaron parámetros de crecimiento, rendimiento, calidad de agua, costos de producción y análisis proximal de los flóculos. El oxígeno disuelto se mantuvo con saturación por encima de 100% y los compuestos nitrogenados (NO2 = 0,4-0,5 mg/l, NO3 = 0,4-0,5 mg/l, NH3 = 0,2-0,3 mg/l, TAN = 2,2-2,4 mg/l) no presentaron diferencias entre los tratamientos (P > 0,05). Los pesos finales de la cachama (173,5-196,2 g) fueron entre dos y cuatro veces los obtenidos por la tilapia (43,0-87,9 g). El mejor rendimiento del bicultivo se obtuvo con la dieta T24 (11,4 ± 1,3 kg/m³), el cual también registró el menor FCA (0,9 ± 0,3). Producir un kilogramo de pescado costó entre COP $3.148 (T24) y COP $4.445 (T32); del cual el alimento representó entre 49,2% (T16) y 63,3% (T32) y la energía, entre 10,3% (T32) y 14,2% (T16) de los costos. El análisis proximal de los flóculos registró niveles de proteína bruta (29-36% PB) adecuados para cachama y tilapia; pero con niveles bajos de lípidos (< 1,0%). El desempeño productivo y los costos de producción permiten sugerir la viabilidad que ofrece el sistema biofloc para la producción de carne de pescado con alimento de 24% PB de origen vegetal.

The productive performance of cachama and nile tilapia reared in biofloc and fed diets of vegetal origin was evaluated. In 1000L tanks with permanent aeration, were placed 80 fish/m3, in a ratio 1:1 (cachama : tilapia); fish were fed with three levels of crude protein (CP): 16% (T16), 24% (T24) and 32% (T32) for 120 days. Parameters of growth, yield, water quality, production costs and proximal analysis of the flocs were estimated. Dissolved oxygen showed saturation above 100% and nitrogen compounds (NO2 = 0.4-0.5 mg/l, NO3 = 0.4-0.5 mg/l, NH3 = 0.2-0.3 mg/l, TAN = 2.2-2.4 mg/l) showed no statistical difference between treatments (P > 0.05). The final weight of the cachama (173.5-196.2 g) were between two and four times those obtained by tilapia (43.0-87.9 g). The tilapia recorded a better daily gain of weight in T24 (0.7 g/day); while the cachama ranged between 1.2-1.3 g/day, with no significant difference between these values (P > 0.05). The best bi-culture yield was obtained in T24 diet (11.4 ± 1.3 kg/ m³), which also recorded the lowest FCA (0.9 ± 0.3). To produce one kilogram of fish cost between COP$3.148 (T24) and COP$4.445 (T32); of which the food represented between 49.2% (T16) and 63.3% (T32) and energy between 10.3% (T32) and 14.2% (T16) of total costs. Proximal analysis of the flocs recorded crude protein levels suitable (29-36% PB) for cachama and tilapia; but with low lipid levels (< 1.0%). The productive performance and the production costs allow to suggest the viability of the biofloc system for the production of fish meat with 24% CP diet of vegetal origin.