Oxygen and hydrocarbon volumetric transfer coefficients in the production of an oil-degrading bacterial consortium: emulsifying activity and surface tension in a bioreactor.

Our work shows that in multiphase systems, it is more important to take into account the mass transfer of oil rather than that of just oxygen. The oxygen volumetric transfer coefficient is important in aerobic bioreactor design. However, in multiphase systems with non-soluble substrates, oil transfer can impose larger restrictions but is usually not considered. Emulsification and surface tension could play an important role due to effects on oil droplet size and interfacial transfer area. Petroleum oil and is derivates such as diesel can negatively affect living organisms. This study evaluated the effects of the volumetric transfer coefficients (kLa) of hydrocarbons and oxygen on the production of an oil-degrading consortium in an airlift bioreactor relative to emulsifying activity and surface tension, which play important roles in the biodegradation of non-soluble substrates such as diesel due to a combined mass transfer constraint. Our results showed a clear difference in kLa values, which ranged from 15 to 91 h-1 for oxygen and from 0 to 0.0014 h-1 for diesel. Most aerobic biodegradation studies focus on the oxygen volumetric transfer coefficient (kLaoxygen), but our results indicated that non-soluble constraints, such as the volumetric transfer coefficient of diesel (kLadiesel), could be more important. Additionally, d32diesel decreased as superficial gas velocity (Ug) increased. Lower Ug rates (0.15 cm s-1) resulted in higher values of d32diesel (0.38 cm-1), whereas higher Ug rates (2.7 cm s-1) resulted in lower values of d32diesel (0.21 cm-1) at the beginning of the cultivation.

Mutational Landscape of Bladder Cancer in Mexican Patients: KMT2D Mutations and chr11q15.5 Amplifications Are Associated with Muscle Invasion.

Bladder cancer (BC) is the most common neoplasm of the urinary tract, which originates in the epithelium that covers the inner surface of the bladder. The molecular BC profile has led to the development of different classifications of non-muscle invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC). However, the genomic BC landscape profile of the Mexican population, including NMIBC and MIBC, is unknown. In this study, we aimed to identify somatic single nucleotide variants (SNVs) and copy number variations (CNVs) in Mexican patients with BC and their associations with clinical and pathological characteristics. We retrospectively evaluated 37 patients treated between 2012 and 2021 at the National Cancer Institute-Mexico (INCan). DNA samples were obtained from paraffin-embedded tumor tissues and exome sequenced. Strelka2 and Lancet packages were used to identify SNVs and insertions or deletions. FACETS was used to determine CNVs. We found a high frequency of mutations in TP53 and KMT2D, gains in 11q15.5 and 19p13.11-q12, and losses in 7q11.23. STAG2 mutations and 1q11.23 deletions were also associated with NMIBC and low histologic grade.

Cholinergic neurons constitutively engage the ISR for dopamine modulation and skill learning in mice.

The integrated stress response (ISR) maintains proteostasis by modulating protein synthesis and is important in synaptic plasticity, learning, and memory. We developed a reporter, SPOTlight, for brainwide imaging of ISR state with cellular resolution. Unexpectedly, we found a class of neurons in mouse brain, striatal cholinergic interneurons (CINs), in which the ISR was activated at steady state. Genetic and pharmacological manipulations revealed that ISR signaling was necessary in CINs for normal type 2 dopamine receptor (D2R) modulation. Inhibiting the ISR inverted the sign of D2R modulation of CIN firing and evoked dopamine release and altered skill learning. Thus, a noncanonical, steady-state mode of ISR activation is found in CINs, revealing a neuromodulatory role for the ISR in learning.

Antioxidant Activity of Collagen Extracts Obtained from the Skin and Gills of Oreochromis sp.

Efforts aimed at reduction of fishing waste generated during the evisceration and filleting are scarce. The fishing waste is used in the production of low value-added products, such as flours or silages. It is important to visualize an alternative and profitable use of this waste, as it constitutes a serious environmental problem. This research determined the antioxidant properties of collagenous extracts of skin and galls of Oreochromis sp. The raw materials were characterized by proximal chemical analysis. Three treatments were applied to extract the collagen: salt-soluble collagen, acid-soluble collagen (ASC), and pepsin-hydrolyzed collagen (PHC). The collagenous fractions were hydrolyzed (0.1% pepsin). The recovered collagen yield and antioxidant activity were determined to hydrolyzed collagen (HC) and nonhydrolyzed collagen (NHC). The ASC skin showed the highest extraction yield (3.02%). For galls, only the PHC extraction was feasible (0.16%). Antioxidant analysis of NHC did not reveal radical scavenging activities. HC displayed a 2,2-diphenyl-1-picrylhydrazyl %RSA of 22.58 (ASC skin) and 10.34% (PHC galls), and a 2,2'-azino-bis[3-ethylbenzothiazoline-6-sulfonic acid] %RSA of 30.40% (PHC skin) and 29.43% (PHC galls), respectively. The ASC skin and PHC gall extracts exhibited 94.40% and 81.54% in ferric-reducing antioxidant power, and 43.63 and 38.08 µg ascorbic acid equivalents per milli liter for total antioxidant capacity, respectively. The collagen extracts showed %RSA and chelation of pro-oxidant metal ions. Different mechanism of antioxidant action was identified for the extracts: radical scavengers for HC and metal ion chelators for NHC. In conclusion, red tilapia skin collagen is recommended as an active ingredient of nutraceuticals, pharmaceuticals, or functional foods, for the identified bioactive properties.

Muscarinic presynaptic modulation in GABAergic pallidal synapses of the rat.

The external globus pallidus (GPe) is central for basal ganglia processing. It expresses muscarinic cholinergic receptors and receives cholinergic afferents from the pedunculopontine nuclei (PPN) and other regions. The role of these receptors and afferents is unknown. Muscarinic M1-type receptors are expressed by synapses from striatal projection neurons (SPNs). Because axons from SPNs project to the GPe, one hypothesis is that striatopallidal GABAergic terminals may be modulated by M1 receptors. Alternatively, some M1 receptors may be postsynaptic in some pallidal neurons. Evidence of muscarinic modulation in any of these elements would suggest that cholinergic afferents from the PPN, or other sources, could modulate the function of the GPe. In this study, we show this evidence using striatopallidal slice preparations: after field stimulation in the striatum, the cholinergic muscarinic receptor agonist muscarine significantly reduced the amplitude of inhibitory postsynaptic currents (IPSCs) from synapses that exhibited short-term synaptic facilitation. This inhibition was associated with significant increases in paired-pulse facilitation, and quantal content was proportional to IPSC amplitude. These actions were blocked by atropine, pirenzepine, and mamba toxin-7, suggesting that receptors involved were M1. In addition, we found that some pallidal neurons have functional postsynaptic M1 receptors. Moreover, some evoked IPSCs exhibited short-term depression and a different kind of modulation: they were indirectly modulated by muscarine via the activation of presynaptic cannabinoid CB1 receptors. Thus pallidal synapses presenting distinct forms of short-term plasticity were modulated differently.