Beneficiation of eucalyptus tree barks in the context of an integrated biorefinery – Optimisation of accelerated solvent extraction (ASE) of polyphenolic compounds using response surface methodology

Bark from trees obtained from sustainably managed plantations used in the production of timber, pulp and paper is an under-utilised waste in many countries across the world. However, in the context of an integrated biorefinery, they may serve as a valuable feedstock for the production of high-value products for increased revenue generation and mitigation of environmental impacts for the ailing forestry, timber, pulp and paper industry. In this study, optimum accelerated solvent extraction conditions were established for the recovery of total polyphenolic compounds (TPC) and total extractive content (TEC) from barks obtained from four Eucalyptus tree species (E.dunnii, E.grandis, E.smithii and E.nitens). Using a response surface methodology and Box-Behnken experimental design, optimum extraction conditions found were an extraction temperature of 117 °C, three extraction cycles, and a milled bark particle size class of 500–850 μm. E. smithii showed the highest TEC at 21.9% and the highest TPC at 4.7 g/100 g gallic acid equivalents (GAE).     

NMDA receptor trafficking at recurrent synapses stabilizes the state of the CA3 network

Metaplasticity describes the stabilization of synaptic strength such that strong synapses are likely to remain strong while weak synapses are likely to remain weak. A potential mechanism for metaplasticity is a correlated change in both N-methyl-D-aspartate (NMDA) receptor-mediated postsynaptic conductance and synaptic strength. Synchronous activation of CA3-CA3 synapses during spontaneous bursts of population activity caused long-term potentiation (LTP) of recurrent CA3-CA3 glutamatergic synapses under control conditions and depotentiation when NMDA receptors were partially blocked by competitive antagonists. LTP was associated with a significant increase in membrane-bound NMDA receptors, whereas depotentiation was associated with a significant decrease in membrane-bound NMDA receptors. During burst activity, further depotentiation could be induced by sequential reductions in antagonist concentration, consistent with a depotentiation-associated reduction in membrane-bound NMDA receptors. The decrease in number of membrane-bound NMDA receptors associated with depotentiation reduced the probability of subsequent potentiation of weakened synapses in the face of ongoing synchronous network activity. This molecular mechanism stabilizes synaptic strength, which in turn stabilizes the state of the CA3 neuronal network, reflected in the frequency of spontaneous population bursts.     

Myxoid glioneuronal tumor,PDGFRA p.K385‐mutant: clinical,radiologic, and histopathologic features

“Myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” is a recently described tumor entity of the central nervous system with a predilection for origin in the septum pellucidum and a defining dinucleotide mutation at codon 385 of the PDGFRA oncogene replacing lysine with either leucine or isoleucine (p.K385L/I). Clinical outcomes and optimal treatment for this new tumor entity have yet to be defined. Here, we report a comprehensive clinical, radiologic, and histopathologic assessment of eight cases. In addition to its stereotypic location in the septum pellucidum, we identify that this tumor can also occur in the corpus callosum and periventricular white matter of the lateral ventricle. Tumors centered in the septum pellucidum uniformly were associated with obstructive hydrocephalus, whereas tumors centered in the corpus callosum and periventricular white matter did not demonstrate hydrocephalus. While multiple patients were found to have ventricular dissemination or local recurrence/progression, all patients in this series remain alive at last clinical follow‐up despite only biopsy or subtotal resection without adjuvant therapy in most cases. Our study further supports “myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” as a distinct CNS tumor entity and expands the spectrum of clinicopathologic and radiologic features of this neoplasm.     

Diabetes and COVID-19 in Congolese patients

BackgroundThe global pandemic Coronavirus Disease 2019 (COVID-19) due to the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is reported to be potentially severe in patients with morbid conditions. One common reported comorbidities is diabetes. We aimed in this study to precise the clinical characteristics and outcomes in a series of congolese diabetic patients affected by COVID-19 infection.Patients and methodsWe retrospectely studied from 256 COVID-19 patients, a cohort of 30 persons with previously known diabetes. The glycaemia controls have been obtained by plasma glucose assay. All patients have been tested positive to SARS-CoV-2 by RT-PCR method.ResultsThe COVID-19 diabetic patients represented 11,7% of all COVID-19 patients with confidence interval of 95% [7,77–15,65]. Older individuals and male sex were predominent. Dyspnea and sauration of oxygen < 90 were significatives and added risk factors were noted in 63.3% of patients, particulary hyperglycaemia with hypertension or obesity. The mortality rate at the percentage of 36.7% was more prevalent in patients with added comorbidities (30%) versus without comorbidities (6.7%).ConclusionCongolese COVID-19 diabetic patients of male sex and older age exhibiting arterial hypertension and obesity are the most exposed to severe COVID-19 and increasead mortality rate.     

A TASK3 channel (KCNK9) mutation in a genetic model of absence epilepsy

Childhood absence epilepsy is an idiopathic, generalized, nonconvulsive epilepsy with a multifactorial genetic etiology. The KCNK9 gene coding for the TASK3 (Twik-like acid-sensitive K相似文献   

Upper airway abnormalities in Canavan disease

OBJECTIVE: To describe upper airway anatomical abnormalities associated with Canavan disease. METHODS: Retrospective case report. RESULTS: Physical examination and laryngoscopy demonstrated oropharyngeal narrowing, macroglossia, and bronchial asymmetry in a child with Canavan disease. Tracheostomy decreased problems with chronic aspiration and obstructive sleep apnea. CONCLUSIONS: Oropharyngeal obstruction and bronchial asymmetry are previously undescribed upper airway abnormalities found in an individual with Canavan disease. Tracheostomy is an effective method of managing chronic aspiration and obstruction in these patients.     

Management of multifocal and multicentric gliomas

The diffuse nature of gliomas has long confounded attempts at achieving a definitive cure. The advent of computed tomography and magnetic resonance imaging made it increasingly apparent that gliomas could have a multifocal or multicentric appearance. Treating these tumors is the summit of an already daunting challenge, because the obstacles that must be surmounted to treat gliomas in general, namely, their heterogeneity, diffuse nature, and ability to insidiously invade normal brain, are more conspicuous in this subset of tumors.