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Transparent conductive metal oxides are interesting materials for various optoelectronic applications including solar cells and flat panel displays. This study focuses on the in situ deposition of aluminum-doped zinc oxide (AZO) thin layers on c-axis oriented sapphire substrates by dc sputtering and on the structural and electrical characterization. The films have a typical thickness of 90 nm and a roughness of 10 nm root mean square. An Al/Zn ratio of 2.4 at% Al was determined by X-ray photoelectron spectroscopy. X-ray diffraction shows a preferential growth in the (0002) c-axis direction. Films have an average transparency of 90% in the visible-light spectrum, a room-temperature resistivity of 3.7 × 10−3 Ω cm and a carrier mobility of 6.7 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

In August 2022, powdery mildew symptoms were detected on lettuce (Lactuca sativa) in a commercial field located in Quecholac, Puebla, Mexico. Signs appeared as whitish powdery masses on leaves. Disease incidence was about 100% and signs covered up to 40% of leaf surface. Mycelium was amphigenous forming white patches. Hyphal appressoria were indistinct or nipple-shaped and solitary. Conidiophores (n= 30) were hyaline, erect, arising from the upper surface of hyphal mother cells or lateral, and of 90 to 201 μm long. Foot cells were cylindrical, of 49 to 92 × 10-15 μm, followed by 1-3 shorter cells, and forming conidia in chains. Conidia (n= 100) were hyaline, ellipsoid-ovoid, doliiform-subcylindrical, 27 to 40 × 14 to 20 μm. Conidial germination belonging to the Euoidium type. Chasmothecia were not observed. The morphological characters were consistent with those of Golovinomyces bolayi (Braun et al. 2019). A voucher specimen was deposited in the Herbarium of the Department of Agricultural Parasitology at the Chapingo Autonomous University under accession number UACH451. To confirm the identification of the fungus, genomic DNA was extracted from conidia and mycelium following the CTAB method (Doyle and Doyle 1990), and the internal transcribed spacer (ITS) region was amplified by PCR using the primers ITS5/ITS4 (White et al. 1990) and sequenced. The resulting 506 bp sequence had 100% identity to those of G. bolayi (LC417109 and LC417106). Phylogenetic analyses using the Maximum Likelihood and Maximum Parsimony methods were performed and confirmed the results obtained in the morphological analysis. The isolate UACH451 grouped in a clade with isolates of G. bolayi. The ITS sequence was deposited in GenBank under accession number OR467546. Pathogenicity was confirmed by gently dusting conidia onto ten leaves of healthy lettuce plants. Five non-inoculated leaves served as controls. The plants were maintained in a greenhouse at 25 to 30 ºC, and relative humidity of 70%. All inoculated leaves developed similar symptoms to the original observation after 10 days, whereas control leaves remained disease free. Microscopic examination of the fungus on inoculated leaves showed that it was morphologically identical to that originally observed. Based on morphological data and phylogenetic analysis, the fungus was identified as G. bolayi. This pathogen has been previously reported causing powdery mildew on lettuce in Argentina, Canada, Chile, Ecuador, Peru, USA and Venezuela (Braun et al. 2019; Mieslerová et al. 2020). To our knowledge, this is the first report of G. bolayi causing powdery mildew on lettuce in Mexico.

A charge-transfer (CT) interaction between 1,3,5-trinitro-2,4-dimethylbenzene (TNX) and anionic phosphate is evaluated, yielding a high band electronic transfer interaction that can be observed as a distinct color change when phosphate is present in solution. The induced interaction was studied using 1 H NMR, UV-visible, and Fourier transform infrared spectroscopies. The stoichiometric determination of the interaction was divined by means of continuous variation, applying the Schaeppi-Treadwell method to calculate the binding constant ( k ). Furthermore, the effect of the polarity of solvents toward the generation of the CT interaction was examined, with multiple solvents considered. Complex deconstruction studies were undertaken, examining the effects of water on complex destruction and understanding the volumes needed to hinder the CT interaction potency. Specificity and selectivity of the CT interaction were also studied against other biologically relevant species (CH 3 CH 2 OH, Na + , K + , Ca 2+ , Cl - , HCO 3 - , F - , CH 3 COO - , and SO 4 2- ), assessing the capabilities of the assay to differentiate anionic species and counter cations that could act as interferences. The role of TNX concentration in CT formation was also analyzed, aiming to optimize the phosphate-sensing assay and improve its limit of detection. The sensing platform was subsequently used to study phosphate concentrations in urine samples to further understand its potential application in biomedical research. To validate the developed technique, urine samples were analyzed for their phosphate content with both the developed sensor and a validated vanadate-molybdate reagent. The results indicate that the sensing method is capable of accurately reporting elevated phosphate levels in urine samples in a rapid and sensitive manner, illustrating that the colorimetric test could be used as a prescreening test for conditions such as hyperphosphatemia or chronic kidney disease., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Ovarian fibrosarcomas are extremely rare tumors with little genomic information available to date. In the present report we present the tumoral exome and transcriptome and the germinal exome of an ovarian fibrosarcoma from a 9-years old child. We found a paucity of mutations (0.77/Mb) and CNV alterations. Of these, the most relevant were a point mutation in the metal-binding site of the microRNA-processing DICER1 enzyme and a frame-shift alteration in the tumor suppressor gene NF1. We validated a germinal truncating mutation in DICER1, which was consistent with a DICER1 Syndrome diagnosis, providing the first example of an ovarian fibrosarcoma as the presenting neoplasia in this syndrome. Network and enrichment analyses showed that both a mesenchymal signature and a Hedgehog cascade could be driving the progression of this tumor. We were also able to find a global lincRNA deregulation, as the number of lincRNAs transcripts expressed in the tumor was decreased, with a concomitant upregulation of previously described non-coding transcripts associated with cancer, such as MALAT1, MIR181A1HG, CASC1, XIST and FENDRR. DICER1 Syndrome should be considered as a possible diagnosis in children ovarian fibrosarcoma. The role of lncRNAs in neoplasias associated with DICER1 alterations need to be studied in more detail.

In this work we examine the role of lateral phase separation in cholesterol-containing biomimetic membranes on the disrupting action of melittin using a label-free surface-sensitive technique, quartz crystal microbalance with dissipation monitoring (QCM-D). Melittin disruption mechanisms depend strongly on the geometry of the lipid layer; however, despite the interplay between layer geometry/thickness and melittin activity, results indicate that the presence of lipid heterogeneity and lateral phase separation greatly influences the disrupting efficiency of melittin. In homogeneous non-raft forming membranes with high cholesterol content, melittin spontaneous activity is strongly delayed compared to heterogeneous raft-forming systems with the same amount of cholesterol. These results confirm the importance of lateral phase separation as a determinant factor in peptide activity. The information provided can be used for the design of more efficient antimicrobial peptides and the possibility of using a label-free approach for tailored-membranes and interactions with other types of peptides, such as amyloid peptides., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Islet transplantation can restore normoglycemia to patients with unstable type 1 diabetes mellitus, but long-term insulin independence is usually not sustained. Identification of predictor(s) of islet allograft dysfunction (IGD) might allow for early intervention(s) to preserve functional islet mass., Methods: Fourteen islet transplantation recipients with long-term history of type 1 diabetes mellitus underwent metabolic testing by mixed meal tolerance test, intravenous glucose tolerance test, and arginine stimulation test every 3 months postislet transplant completion. Metabolic responses were compared between subjects who maintained insulin independence at 18 months (group 1; n=5) and those who restarted insulin within 18 months (group 2; n=9). Data were analyzed before development of islet graft dysfunction and while insulin independent., Results: The 90-min glucose, time-to-peak C-peptide, and area under the curve for glucose were consistently higher in group 2 and increased as a function of time. At 12 months, acute insulin release to glucose in group 2 was markedly reduced as compared with baseline (5.62+/-1.21 microIU/mL, n=4 vs. 16.14+/-3.69 microIU/mL, n=8), whereas it remained stable in group 1 (22.36+/-4.98 microIU/mL, n=5 vs. 27.70+/-2.83 microIU/mL, n=5). Acute insulin release to glucose, acute C-peptide release to glucose (ACpRg), and mixed meal stimulation index were significantly decreased and time-to-peak C-peptide, 90-min glucose, and area under the curve for glucose were significantly increased when measured at time points preceding intervals where IGD occurred compared with intervals where there was no IGD., Conclusions: The intravenous glucose tolerance test and mixed meal tolerance test may be useful in the prediction of IGD and should be essential components of the metabolic testing of islet transplant recipients.

The initial success of islet transplantation (ITx) is followed by graft dysfunction (GDF) and insulin reintroduction. Exenatide, a GLP-1 agonist, increases insulin and decreases glucagon secretion and has potential for beta-cell regeneration. To improve functional islet mass, exenatide treatment was given to ITx recipients with GDF. The objective of this study was to assess metabolic and hormonal effects of exenatide in GDF. In this prospective, single-arm, nonrandomized study, 11 type 1 diabetes recipients of ITx with GDF had HbA1c, weight, insulin requirements, and 5-h mixed meal tolerance test (MMTT; with/without exenatide given before test) at baseline, 3, 6, and 12 months after initiating exenatide treatment. Baseline MMTT showed postprandial hyperglycemia and hyperglucagonemia. Daily exenatide treatment resulted in improved glucose, increased amylin/insulin ratio, and decreased proinsulin/insulin ratio as assessed by MMTT. Glucagon responses remained unchanged. Exenatide administration 1 h before MMTT showed decreased glucagon and glucose at 0 min and attenuation in their postprandial rise. Time-to-peak glucose was delayed, followed by insulin, proinsulin, amylin, and C-peptide, indicating glucose-driven insulin secretion. Five subjects completed 12-month follow-up. Glucose and glucagon suppression responses after MMTT with exenatide were no longer observed. Retrospective 3-month analysis of these subjects revealed higher and sustained glucagon levels that did not suppress as profoundly with exenatide administration, associated with higher glucose levels and increased C-peptide responses. In conclusion, Exenatide suppresses the abnormal postprandial hyperglucagonemia and hyperglycemia observed in GDF. Changes in amylin and proinsulin secretion may reflect more efficient insulin processing. Different degrees of responsiveness to exenatide were identified. These may help guide the clinical management of ITx recipients.

Background: Progressive graft dysfunction (GDF) and loss of insulin independence (II) have been invariably observed in islet transplant recipients under the "Edmonton protocol." To reestablish II, we performed supplemental islet infusions (SI) in recipients of allogeneic islet transplant alone, displaying GDF. To improve the engraftment and long-term graft function of SI, exenatide (EXN) and etanercept treatment at islet infusion, and long-term EXN treatment were tested in a non-randomized pilot clinical trial., Methods: Patients with GDF received SI under Edmonton-like immunosuppression with daclizumab induction, either without interventions (SI-control; n=5) or with EXN and etanercept treatment (SI-EXN; n=4). Clinical and metabolic profiles were assessed during 18-month follow-up., Results: Long-term II (18 months) was observed in 100% of SI-EXN and in 20% of SI-control (P=0.04). SI-EXN subjects demonstrated restoration of function better than that seen after initial islet infusions. Comparison of SI-EXN and SI-control groups demonstrated better responses in SI-EXN subjects at 3 months post-SI. During the 18 months of follow-up, function was sustained in the SI-EXN subjects better than in SI-controls. Acute effects of EXN during mixed meal tolerance test and intravenous glucose tolerance test results in improved first and second phase insulin release in response to intravenous glucose tolerance test and suppressed postprandial hyperglucagonemia after mixed meal tolerance test., Conclusion: These results suggest that the combination of EXN and etanercept improve engraftment and long-term islet survival and function in subjects undergoing SI. This data, however, must be interpreted with some caution because of small sample size, lack of randomization, and sequential comparison with historical controls.

Background: A current limitation of islet transplantation is reduced long-term graft function. The glucagon-like peptide-1 receptor agonist, exenatide (Byetta, Amylin Pharmaceuticals, CA) has properties that could improve existing islet function, prevent further loss of islet mass and possibly even stimulate islet regeneration., Methods: This prospective study evaluated the safety, efficacy, and metabolic effects of exenatide in subjects with type 1 diabetes mellitus and islet allograft dysfunction requiring exogenous insulin., Results: Sixteen subjects commenced exenatide, 12 continue (follow-up 214+/-57 days; range 108-287), four (25%) discontinued medication because of side effects. At 6 months, exogenous insulin was significantly reduced with stable glycemic control (0.15+/-0.02 vs. 0.11+/-0.025 U/kg per day; P<0.0001); three subjects discontinued insulin from 4, 5, and 9 U/day, respectively, two sustained insulin independence with A1c reduction below graft dysfunction criteria. Postprandial capillary blood glucose was significantly decreased (129.4+/-3.8 vs. 118.7+/-4.6 mg/dL; P<0.001), C-peptide and C-peptide-to-glucose ratio increased significantly by 5th and 6th months of treatment (ratio, 1.09+/-0.15 vs. 1.52+/-0.18; P<0.05). Weight loss more than 3 kg occurred in 8 of 12 (67%) subjects. Stimulation testing demonstrated improved glucose disposal and C-peptide secretion (glucose area under the curve 52,332+/-3,219 vs. 42,072+/-1,965; P=0.002 mg x min x dL, mixed meal stimulation index 0.50+/-0.06 vs. 0.66+/-0.09; P=0.03 pmol x mL), with marked suppression of glucagon secretion and progressive increase in amylin secretion. Side effects were more frequent and severe compared with published reports in type 2 diabetes, tolerated doses were lower., Conclusions: Exenatide was tolerated in this patient population after appropriate dose titration and there appeared to be gradual but sustained positive effects on glycemic control and islet graft function.

Background: This study evaluated the effects of islet allotransplantation (ITx) on metabolic control utilizing a continuous glucose monitoring system (CGMS) and assessed its effectiveness as an indicator and predictor of graft dysfunction (GD)., Methods: Glycemic control was assessed in 25 patients with type 1 diabetes mellitus (T1DM); 12 ITx recipients and 13 controls. Mean interstitial glucose, standard deviation (SD), glucose variability, and percentage of time in hyperglycemia (%GT >140 mg/dl), hypoglycemia (%GT <54 mg/dl), and normoglycemia (%GT 54-140 mg/dl) were measured in 72-hour time periods from CGMS recordings in the control group at baseline and in the ITx group at 3, 6, 9, 12, 15, and 18 months after ITx completion and were analyzed as predictors and indicators of GD. Hemoglobin A1c (HbA1c), 90-minute glucose after a mixed meal tolerance test, fasting C-peptide/glucose ratio, and insulin requirements were followed., Results: Compared to the control group, the percentage of time in hypoglycemia was significantly lower in the ITx group at all time points; time in normoglycemia was increased at all times except at 15 months; and time in hyperglycemia was significantly lower at 6, 9, 12, and 18 months. Mean glucose and glucose variability were significantly lower in the ITx group at all times except at 3 and 15 months, whereas HbA1c and 90-minute glucose were significantly lower in the ITx group at all time points. Mean glucose, SD, glucose variability, and %GT >140 mg/dl were significant as indicators but not as predictors of GD., Conclusions: The CGMS demonstrated the benefits of ITx in T1DM, with improvements in glycemic control apparent up to 18 months after transplant. CGMS measures were found to be indicators of GD.