Cell walls are essential for fungal survival and growth. Fungal walls are ∼ 90% carbohydrate, mostly types not found in humans, making them promising targets for anti-fungal drug development. Echinocandins, which inhibit the essential β-glucan synthase, are already clinically available. In contrast, α-glucan, another abundant fungal cell wall component has attracted relatively little research attention because it is not essential for most fungi. Aspergillus nidulans has two α-glucan synthases (AgsA and AgsB) and two α-amylases (AmyD and AmyG), all of which affect α-glucan synthesis. Gene deletion showed that AgsB was the major synthase. In addition, AmyG promoted α-glucan synthesis whereas AmyD had a repressive effect. The lack of α-glucan had no phenotypic impact on solid medium, but reduced conidial adhesion during germination in shaken liquid. Moreover, α-glucan level correlated with resistance to Calcofluor White. Intriguingly, overexpression of agsA could compensate for the loss of agsB at the α-glucan level, but not for phenotypic defects. Thus, products of AgsA and AgsB have different roles in the cell wall, consistent with agsA being mainly expressed at conidiation. These results suggest that α-glucan contributes to drug sensitivity and conidia adhesion in A. nidulans, and is differentially regulated by two synthases and two amylases.

Long segmental repair of trachea stenosis is an intractable condition in the clinic. The reconstruction of an artificial substitute by tissue engineering is a promising approach to solve this unmet clinical need. 3D printing technology provides an infinite possibility for engineering a trachea. Here, we 3D printed a biodegradable reticular polycaprolactone (PCL) scaffold with similar morphology to the whole segment of rabbits’ native trachea. The 3D-printed scaffold was suspended in culture with chondrocytes for 2 (Group I) or 4 (Group II) weeks, respectively. This in vitro suspension produced a more successful reconstruction of a tissue-engineered trachea (TET), which enhanced the overall support function of the replaced tracheal segment. After implantation of the chondrocyte-treated scaffold into the subcutaneous tissue of nude mice, the TET presented properties of mature cartilage tissue. To further evaluate the feasibility of repairing whole segment tracheal defects, replacement surgery of rabbits’ native trachea by TET was performed. Following postoperative care, mean survival time in Group I was 14.38 ± 5.42 days, and in Group II was 22.58 ± 16.10 days, with the longest survival time being 10 weeks in Group II. In conclusion, we demonstrate the feasibility of repairing whole segment tracheal defects with 3D printed TET.

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Severity stratification and prognostic prediction at early stage is crucial for reducing the rates of mortality of patients with acute pancreatitis (AP). We aim to investigate the predicting performance of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and red-cell distribution width (RDW) combined with severity scores (sequential organ failure assessment [SOFA], bed-side index for severity of AP [BISAP], Ranson criteria, and acute physiology and chronic health evaluation II [APACHE II]) for severe AP (SAP) and mortality. A total of 406 patients diagnosed with AP admitted in a tertiary teaching hospital were enrolled. Demographic information and clinical parameters were retrospectively collected and analyzed. NLR, PLR, RDW, blood urea nitrogen (BUN), and AP severity scores (SOFA, BISAP, Ranson, and APACHE II) were compared between different severity groups and the survival and death group. Receiver-operating characteristic (ROC) curves for SAP and 28-day mortality were calculated for each predictor using cut-off values. Area under the curve (AUC) analysis and logistic regression models were performed to compare the performance of laboratory biomarkers and severity scores. Our results showed that NLR, PLR, RDW, glucose, and BUN level of the SAP group were significantly increased compared to the mild acute pancreatitis (MAP) group on admission ( P < .001). The severity of AP increased as the NLR, SOFA, BISAP, and Ranson increased ( P < .01). The AUC values of NLR, PLR, RDW, BUN, SOFA, BISAP, Ranson, and APACHE II to predict SAP were 0.722, 0.621, 0.787, 0.677, 0.806, 0.841, 0.806, and 0.752, respectively, while their AUC values to predict 28-day mortality were 0.851, 0.693, 0.885, 0.765, 0.968, 0.929, 0.812, and 0.867, respectively. BISAP achieved the highest AUC, sensitivity and NPV in predicting SAP, while SOFA is the most superior in predicting mortality. The combination of BISAP + RDW achieved the highest AUC (0.872) in predicting SAP and the combination of SOFA + RDW achieved the highest AUC (0.976) in predicting mortality. RDW (OR = 1.739), SOFA (OR = 1.554), BISAP (OR = 2.145), and Ranson (OR = 1.434) were all independent risk factors for predicting SAP, while RDW (OR = 7.361) and hematocrit (OR = 0.329) were independent risk factors for predicting mortality by logistic regression model. NLR, PLR, RDW, and BUN indicated good predictive value for SAP and mortality, while RDW had the highest discriminatory capacity. RDW is a convenient and reliable indicator for prediction not only SAP, but also mortality.

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Aim: To study the feasibility of electrospun collagen–poly(L-lactic acid-co-ε-caprolactone) (collagen–PLCL) membranes for cartilage tissue engineering. Materials & methods: Characteristics and mechanical properties of collagen–PLCL membranes were analyzed. The cell affinity of collagen–PLCL membranes with chondrocytes was also assessed. Then, the cell–scaffold constructs were engineered with collagen–PLCL membranes seeded chondrocytes by a sandwich model. After culture for 1 week in vitro, the constructs were implanted subcutaneously into nude mice for 4, 8 and 12 weeks, followed by evaluation of the quality of neocartilage. Results: Collagen–PLCL membranes exhibited excellent balanced properties without cytotoxicity. With the extension of implantation time in vivo, the constructs revealed more cartilage-like tissue especially at 8 and 12 weeks. The Young’s modulus of the constructs also significantly increased and neared that of native cartilage at 12 weeks postimplantation. Conclusion: We suggest that collagen–PLCL membranes facilitate the formation of cartilage and thus may represent a promising scaffold for cartilage tissue engineering.

4'-O-Methylation of an isoflavonoid intermediate is a key reaction in the biosynthesis of the phytoalexin medicarpin in legumes. However, isoflavone O-methyltransferase (IOMT) from alfalfa converts the isoflavone daidzein to 7-O-methyl daidzein (isoformononetin) in vitro as well as in vivo in unchallenged leaves of transgenic alfalfa ectopically expressing IOMT. In contrast, elicitation of IOMT-overexpressing plants with CuCl(2) or infecting these plants with Phoma medicaginis leads to greater accumulation of formononetin (4'-O-methyl daidzein) and medicarpin in the leaves than does elicitation or infection of control plants, and no isoformononetin is detected. Overexpression of IOMT results in increased induction of phenylpropanoid/isoflavonoid pathway gene transcripts after infection but has little effect on basal expression of these genes. IOMT-overexpressing plants display resistance to P. medicaginis. The apparently different regiospecificities of IOMT in vivo and in vitro are discussed in relation to potential metabolic channeling at the entry point into the isoflavonoid pathway.

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