Glial fibrillary acidic protein (GFAP) and CD34 expression in the human optic nerve and brain in methanol toxicity

Enhanced Biosynthesis of d-Allulose from a d-Xylose-Methanol Mixture and Its Self-Inductive Detoxification by Using Antisense RNAs in Escherichia coli

d-Allulose, a C-3 epimer of d-fructose, has great market potential in food, healthcare, and medicine due to its excellent biochemical and physiological properties. Microbial fermentation for d-allulose production is being developed, which contributes to cost savings and environmental protection. A novel metabolic pathway for the biosynthesis of d-allulose from a d-xylose-methanol mixture has shown potential for industrial application. In this study, an artificial antisense RNA (asRNA) was introduced into engineered Escherichia coli to diminish the flow of pentose phosphate (PP) pathway, while the UDP-glucose-4-epimerase (GalE) was knocked out to prevent the synthesis of byproducts. As a result, the d-allulose yield on d-xylose was increased by 35.1%. Then, we designed a d-xylose-sensitive translation control system to regulate the expression of the formaldehyde detoxification operon (FrmRAB), achieving self-inductive detoxification by cells. Finally, fed-batch fermentation was carried out to improve the productivity of the cell factory. The d-allulose titer reached 98.6 mM, with a yield of 0.615 mM/mM on d-xylose and a productivity of 0.969 mM/h.

Optical Coherence Tomography Angiography and Structural Analyses of the Pale Optic Discs: Is It Possible to Differentiate the Cause?

Introduction: To compare the optic nerve head (ONH) structure and microvasculature in patients with optic atrophy due to non-arteritic anterior ischemic optic neuropathy (NAION), compressive optic neuropathy (CON), methanol-induced optic neuropathy (MION), and traumatic optic neuropathy (TON) using optical coherence tomography angiography.Methods: In this comparative, cross-sectional study, 32 eyes with NAION, 18 eyes with CON, 32 eyes with MION, 23 eyes with TON, and 55 normal eyes were enrolled. Radial peripapillary capillary (RPC) vessel density, peripapillary retinal nerve fiber layer (RNFL) thickness, disc area, cup volume, and cup/disc area ratio were obtained using the RTVue XR Avanti system (Optovue Inc., Fremont, CA, USA).Results: RPC vessel density and peripapillary RNFL thickness in all patients were significantly lower than normal subjects. A positive correlation was found between the RPC vessel density and peripapillary RNFL thickness in normal subjects and all study groups. The positive correlation between the inside and outside disc RPC vessel density was only found in the NAION (r = 0.36, P = .042) and MION (r = 0.42, P = .018) groups. No significant difference was found among the groups in terms of peripapillary and inside disc vascular densities (all P > .05). Disc area and cup volume in patients with MION was larger than the values in patients with NAION (P = .018) and TON (P = .044) and normal subjects (P = .015). The discriminating features among the study groups were the larger cup volume and cup/disc area ratio in patients with MION, and lower RNFL thickness in patients with TON.Conclusions: There was a positive correlation between the RNFL thickness and peripapillary RPC vessel density regardless of the cause of optic disc pallor. Structural evaluation of the ONH seems to be a better way to differentiate the cause of optic nerve head atrophy than the microangiographic changes.