Bio-isopropanol production in Corynebacterium glutamicum: Metabolic redesign of synthetic bypasses and two-stage fermentation with gas stripping.

Isopropanol is a commodity chemical widely used as a biofuel, fuel additive, rubbing alcohol and intermediate in various fields. Here, an engineered Corynebacterium glutamicum overproducing isopropanol was developed. To our knowledge, despite a representative industrial host to produce valuable chemicals, the high-level production of isopropanol in C. glutamicum has never been reported. First, the problem of the inability to produce isopropanol was solved by finding a key factor in its metabolism. The consolidation and modular optimization of synthetic bypasses including succinate and mevalonate bypasses enhanced isopropanol production. Flux redistribution of central metabolism significantly directed the carbon flux toward isopropanol biosynthesis. The final engineered strain produced 10.25 ± 1.12 g/L isopropanol in two-stage fed-batch fermentation with an optimized gas stripping, which is the highest titer, yield and productivity in C. glutamicum. These strategies could be useful for the high-level production of isopropanol in C. glutamicum.

Efficient Synthesis of Food-Derived Antioxidant l-Ergothioneine by Engineered Corynebacterium glutamicum.

l-Ergothioneine (EGT) is a strong antioxidant used in industry, and it is commonly extracted from mushrooms; however, its production is limited. As an alternative, we developed metabolically engineered Corynebacterium glutamicum with reinforced sulfur assimilation and pentose phosphate pathways, which led to the accumulation of 45.0 and 63.2 mg/L EGT, respectively. Additionally, the overexpression of cysEKR resulted in further promoted EGT production in ET4 (66.5 mg/L) and ET7 (85.0 mg/L). Based on this result, we developed the strain ET11, in which all sulfur assimilatory, PP, and l-cysteine synthetic pathways were reinforced, and it synthesized 264.4 mg/L EGT. This study presents the first strategy for EGT synthesis that does not require precursor addition in C. glutamicum, and the production time was shortened. In addition, the synthesized EGT showed high radical scavenging activity (70.7%), thus confirming its antioxidant function. Consequently, this study showed the possibility of EGT commercialization by overcoming the limitations of industrial processes.

Management of pulmonary aspiration due to undiagnosed achalasia during induction of general anesthesia - A case report -

Background@#Intraoperative pulmonary aspiration is a rare but potentially fatal complication associated with various risk factors. Preoperative recognition of these risk factors can prevent aspiration events during general anesthesia or facilitate prompt corrective measures in patients experiencing this complication. Case: A 70-year-old female patient with hypertension underwent bilateral total knee arthroplasty under general anesthesia. Despite using a midnight nothing-per-oral (NPO) protocol, an unpredictable intraoperative aspiration event occurred during anesthesia induction. A detailed evaluation of the patient’s medical history and subsequent diagnostic imaging examinations indicated achalasia. She was treated for aspiration pneumonia for 2 weeks. After 2 months, rescheduled total knee arthroplasty was performed under spinal anesthesia without any complications. @*Conclusions@#Obtaining the patient’s medical history and assessing the risk factors are important to prevent unpredictable intraoperative pulmonary aspiration. High-risk patients should undergo adequate preoperative fasting and regional anesthesia or rapid-sequence intubation should be considered for safe induction of general anesthesia.

Effects of Early Postoperative Intraocular Pressure after Ahmed Glaucoma Valve Implantation on Long-term Surgical Outcomes.

PURPOSE: To evaluate the long-term effects of early postoperative intraocular pressure (IOP) after Ahmed glaucoma valve (AGV) implantation on long-term surgical outcomes. METHODS: This retrospective, non-randomized study included 100 eyes of 100 patients who underwent AGV surgery. We divided the enrolled patients into four groups according to the presence of transient hypotony within the first postoperative week or the presence of a hypertensive phase during the first three postoperative months. Postoperative IOP, the number of glaucoma medications, and cumulative success rate were compared among the groups. RESULTS: There was significantly better IOP control and a better success rate in the non-hypertensive phase group 2 years postoperatively. However, no significant difference was found in the IOP or success rate at 2 years postoperatively between the transient hypotony and non-hypotony groups. Further subgroup analysis showed that the non-hypotony, non-hypertensive phase group had a significantly higher success rate (100%) at 2 years postoperatively. CONCLUSIONS: We can predict the long-term prognosis after AGV implantation by considering the early postoperative IOP state and the presence of a hypertensive phase.

Ocular Dominance Is Associated with the Ganglion Cell-Inner Plexiform Layer Thickness Profile in the Macula.

PURPOSE: To investigate the characteristics of macular ganglion cell-inner plexiform layer (GCIPL) thickness profiles associated with ocular dominance. SETTING: Private practice, Seoul, Republic of Korea. DESIGN: Comparative case-control study. METHODS: Both eyes of 199 participants with no ophthalmic abnormalities were included. Participants were imaged by spectral-domain optical coherence tomography, and underwent dominant eye testing using a hole-in-a-card test (sighting dominance) at the same visit. Macular GCIPL, as well as circumpapillary retinal nerve fiber layer (RNFL) thickness were compared for individual patients, according to ocular dominance. RESULTS: Ocular dominance occurred predominantly in the right eye (right vs. left: 72.36 vs. 27.60%; P < 0.001). In the comparison of macular GCIPL thickness, the average (81.27±5.01 µm vs. 80.66±6.31 µm in dominant vs. non-dominant eyes), inferonasal (81.39±5.47µm vs. 80.33±6.82µm, and inferior sectors (77.95±6.05µm vs. 76.97±8.15µm) were significantly different between dominant and non-dominant eyes (P = 0.040, 0.005, and 0.032, respectively). Significant predictors of average GCIPL thickness were spherical equivalent (ß = 1.37, P<0.001), astigmatic power (ß = 1.44, P = 0.009), disc area (ß = 3.90, P < 0.001), average RNFL thickness (ß = 0.22, P<0.001), average cup-to-disc ratio (ß = 5.74, P = 0.002), difference between the inferior and superior quadrant RNFL thicknesses (ß = 0.08, P = 0.024), and ocular dominance (ß = 2.10, P = 0.020). On multivariate regression analysis, ocular dominance was correlated with average GCIPL thickness after adjusting for potential confounders (ß = 1.63, P = 0.048). CONCLUSIONS: Dominant eyes accompanied significantly thicker average macular GCIPL. This information suggests that macular GCIPL thickness may provide an indicator of the relative dominance of an eye.

The Ability of 10-2 Short-Wavelength Perimetry in Detecting Functional Loss of the Macular Area in Preperimetric Glaucoma Patients.

PURPOSE: To better understand functional loss in the macular area of preperimetric glaucoma patients exhibiting structural loss by exploring correlations between parameters of the ganglion cell-inner plexiform layer (GCIPL) and 10-2 short-wavelength perimetry (SWAP). METHODS: One hundred thirty-four patients underwent 10-2 SWAP and conventional 24-2 visual field (VF) testing using a Humphrey field analyzer and macular scanning via Cirrus optical coherence tomography (OCT). Correlations between GCIPL thickness (GCIPLT) and the mean sensitivity (MS) of topographically corresponding areas explored in various VF tests were calculated. Correlations between GCIPL parameters and MS of the VF, in terms of the asymmetries of various VF sectors, were also determined. RESULTS: Glaucoma patients, preperimetric by standard 24-2 VF analysis but exhibiting GCIPL thinning, had lower MS in 10-2 SWAP and central 24-2 VF analyses. The correlations between average GCIPLT and the corresponding MS were significant for both 10-2 SWAP (r = 0.291, P = 0.018) and 24-2 standard automated perimetry (r = 0.235, P = 0.029). The associations between sectoral GCIPLT and the corresponding 10-2 SWAP MS were significant for all sectors, with the highest correlation evident in the inferotemporal (r = 0.324, P = 0.009) and the lowest in the superonasal GCIPL sectors (r = 0.214, P = 0.043). Asymmetric relationships between GCIPLT and 10-2 SWAP MS exhibited similar yet stronger correlations. CONCLUSIONS: Preperimetric glaucoma patients exhibiting structural loss in the macula also had functional loss revealed by 10-2 SWAP, which was less prominent in conventional 24-2 VF. Therefore, if structural abnormality is evident in the macular area, the central VF areas should be further examined even if the standard 24-2 data appear to be normal.

Optic disc hemorrhage is related to various hemodynamic findings by disc angiography.

BACKGROUND: To investigate the hemodynamic characteristics of glaucoma eyes with disc hemorrhage (DH) by disc fluorescein angiography, and its relationship with glaucomatous changes of the optic disc and surrounding retinal nerve fiber layer (RNFL). METHODS: This study included 35 glaucoma eyes with DH who were followed up at least 5 years and had DH at presentation. Eyes were classified as eyes with DH at the border of localized RNFL defects and eyes with DH not related to localized RNFL defects. Prevalence of DH and location of the proximal border were recorded from disc photographs. Fluorescein angiography was performed 3 months after detecting the DH. Arm-retina time, arteriovenous transit time, disc filling time, choroidal filling time, and venous filling time were measured as retinal circulation parameters. The presence of disc filling defects and disc leaks were evaluated. RESULTS: There were 19 (54.3%) eyes with DH accompanying localized RNFL defects. The arm-retina time was prolonged in eyes with DH not related to RNFL defects (P = 0.044) and the arteriovenous transit time was prolonged in eyes with DH accompanying RNFL defects (P = 0.029). Among eyes with DH accompanying RNFL defects, 11 (57.9%) had vessel filling defects or delayed filling indicating blood flow stasis at the cup margin proximal to where DH occurred. Eyes with DH not related to RNFL defects did not show vessel filling defects or delayed filling. CONCLUSIONS AND RELEVANCE: Eyes with DH related to RNFL defects showed prolonged arteriovenous transit time and had frequent vessel filling defects or delayed filling indicating blood flow stasis and thrombus formation at the site DH occurred. These findings suggest that vascular and hemodynamic changes due to glaucomatous structural changes cause DH in relation to localized RNFL defects.

Complementary roles in cancer prevention: protease inhibitor makes the cancer preventive peptide lunasin bioavailable.

BACKGROUND: The lower incidence of breast cancer among Asian women compared with Western countries has been partly attributed to soy in the Asian diet, leading to efforts to identify the bioactive components that are responsible. Soy Bowman Birk Inhibitor Concentrate (BBIC) is a known cancer preventive agent now in human clinical trials. METHODOLOGY/PRINCIPAL FINDINGS: The objectives of this work are to establish the presence and delineate the in vitro activity of lunasin and BBI found in BBIC, and study their bioavailability after oral administration to mice and rats. We report that lunasin and BBI are the two main bioactive ingredients of BBIC based on inhibition of foci formation, lunasin being more efficacious than BBI on an equimolar basis. BBI and soy Kunitz Trypsin Inhibitor protect lunasin from in vitro digestion with pancreatin. Oral administration of (3)H-labeled lunasin with lunasin-enriched soy results in 30% of the peptide reaching target tissues in an intact and bioactive form. In a xenograft model of nude mice transplanted with human breast cancer MDA-MB-231 cells, intraperitoneal injections of lunasin, at 20 mg/kg and 4 mg/kg body weight, decrease tumor incidence by 49% and 33%, respectively, compared with the vehicle-treated group. In contrast, injection with BBI at 20 mg/kg body weight shows no effect on tumor incidence. Tumor generation is significantly reduced with the two doses of lunasin, while BBI is ineffective. Lunasin inhibits cell proliferation and induces cell death in the breast tumor sections. CONCLUSIONS/SIGNIFICANCE: We conclude that lunasin is actually the bioactive cancer preventive agent in BBIC, and BBI simply protects lunasin from digestion when soybean and other seed foods are eaten by humans.