Alcohol dehydrogenase 1 participates in the Crabtree effect and connects fermentative and oxidative metabolism in the Zygomycete Mucor circinelloides

Rosa Angélica Rangel-Porras,Sharel P. Díaz-Pérez,Juan Manuel Mendoza-Hernández,Pamela Romo-Rodríguez,Viridiana Alejandre-Castañeda,Marco I Valle-Maldonado,Juan Carlos Torres-Guzmán,Gloria Angélica Gon 한국미생물학회 2019 The journal of microbiology Vol.57 No.7

Mucor circinelloides is a dimorphic Zygomycete fungus that produces ethanol under aerobic conditions in the presence of glucose, which indicates that it is a Crabtree-positive fungus. To determine the physiological role of the alcohol dehydrogenase (ADH) activity elicited under these conditions, we obtained and characterized an allyl alcohol-resistant mutant that was defective in ADH activity, and examined the effect of adh mutation on physiological parameters related to carbon and energy metabolism. Compared to the Adh+ strain R7B, the ADH-defective (Adh-) strain M5 was unable to grow under anaerobic conditions, exhibited a considerable reduction in ethanol production in aerobic cultures when incubated with glucose, had markedly reduced growth capacity in the presence of oxygen when ethanol was the sole carbon source, and exhibited very low levels of NAD+-dependent alcohol dehydrogenase activity in the cytosolic fraction. Further characterization of the M5 strain showed that it contains a 10-bp deletion that interrupts the coding region of the adh1 gene. Complementation with the wild-type allele adh1+ by transformation of M5 remedied all the defects caused by the adh1 mutation. These findings indicate that in M. circinelloides, the product of the adh1 gene mediates the Crabtree effect, and can act as either a fermentative or an oxidative enzyme, depending on the nutritional conditions, thereby participating in the association between fermentative and oxidative metabolism. It was found that the spores of M. circinelloides possess low mRNA levels of the ethanol assimilation genes (adl2 and acs2), which could explain their inability to grow in the alcohol.

Influence of supplemental canola or soybean oil on milk yield, fatty acid profile and postpartum weight changes in grazing dairy goats

Israel Lerma-Reyes,German D. Mendoza-Martinez,Rolado Rojo-Rubio,Mario Mejia,J.C. Garcia-Lopez,Hector A. Lee-Rangel 아세아·태평양축산학회 2018 Animal Bioscience Vol.31 No.2

Objective: This experiment was designed to evaluate the effect of supplementation with soybean or canola oil on milk production and the composition of long chain fatty acids as well as weight changes in the goats and their kids. Methods: Thirty nine mulitparous crossed Alpine×Nubian goats (initial body weight [BW] 43.5±1.7 kg) from the day of parturition were assigned to the treatments: grazing control (n = 15); grazing plus 20 mL/goat/d of supplemental soybean oil (n = 12); and grazing plus 20 mL/goat/d of supplemental canola oil (n = 12) from November 26, 2014 to March 7, 2015. The planned contrasts were: CI (control vs supplemented with oils); CII (soybean vs canola oil) to compare the treatment effects. Results: The vegetable oil supplementation reduced weight losses in lactating goats (CI: –0.060 vs 0.090 kg/d; p = 0.03) but did not improve milk production or affect kids’ growth. The content of C4, C6, C8, C10, C11, C14, and C18:1n9t in the milk was increased (p<0.05) with respect to control. However, C12, C14, C16, C18, C18:1n9c, C18:2n6c, and C18:3n3 were reduced (p<0.05) in supplemented goats. Conjugated linoleic acid (CLA) was increased (p<0.05) in goats supplemented with oils compared to the control group. Conclusion: Supplementation with 20 mL/d of soybean or canola oil did not affect milk production or kids’ performance; however, it increased CLA concentration and reduced the reduced weight losses in lactating goats.

SYNTHESIS OF MESOPOROUS OF NyTi1-xCexO2-y STRUCTURES AND ITS VISIBLE LIGHT INDUCED PHOTOCATALYTIC PERFORMANCE

R. RANGEL,J. D. GARCÍA-ESPINOZA,I. ESPITIA,P. QUINTANA,P. BARTOLO-PÉREZ,J. J. ALVARADO-GIL,R. TREJO-TZAB 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.5

The present work was addressed to study the visible light induced performance as photocatalysts of mesoporous NyTi1–xCexO2–y structures obtained under microwave irradiation. The titanium dioxide (TiO2) was doped with cerium and nitrogen in order to improve the quantum efficiency of the TiO2 and to shift its adsorption spectra to the visible region. The prepared meso-powders were analyzed by means of X-ray diffraction (XRD), scanning Electron microscopy (SEM), infrared (IR) spectroscopy, transmission electronic microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The surface area was evaluated by means of the Brunauer-Emmett-Teller (BET) method and ultraviolet (UV)-visible diffuse reflectance measurements were performed in order to determine the band gap energy. In addition, the photocatalytic activity of the samples was evaluated by monitoring the photodegradation of methylene blue (MB) under UV and visible light energy irradiation. The results show that our methodology is an effective way for incorporating cerium and nitrogen into TiO2 compound, which in turn, increases its photocatalytic activity. The diffuse reflectance analysis confirms that the absorption edge was shifted towards the visible region of the optical spectrum. The XRD diffraction patterns indicate homogeneous solid solutions in which prevails the anatase phase. It was observed a reduction in crystal size from 13.1 nm to 7.7 nm for NyTi0.98Ce0.02O2–y in comparison to TiO2. The textural properties of the synthesized compounds were determined, by means of adsorption isotherms indicating the formation of mesoporous structures. IR spectra show characteristic vibration signals attributed to Ti–O–Ti bonds, as well as vibrations assigned to cerium and nitrogen bonds. The XPS analyses evidence the presence of Ce3+/Ce4+ redox couple and Ti–N bonds. The photocatalityc efficiency was evaluated in the degradation of MB monitoring the absorbance change at 664 nm. The degradation of this compound was 91.4% using NyTi0.98Ce0.02O2–y as photocatalyst under UV energy in 90 min. Also 38.7% of MB degradation was achieved in 150 min under visible light radiation.

Topical and Systemic Anti-Inflammatory Effects of Echinodorus macrophyllus (Kunth) Micheli (Alismataceae)

Ellen Tanus-Rangel,Scheila R. Santos,Lousa˜ Lopes,Vaˆnia Noldin,Franco D. Monache,Valdir Cechinel-Filho,Domingos T.O. Martins 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.5

Echinodorus macrophyllus leaf has been used in Brazilian folk medicine to treat inflammatory conditions and kidney dysfunctions. The present study evaluated the effects of leaf ethanolic extract from E. macrophyllus (EEEm) in acute and subchronic models of inflammation. The EEEm was found to cause significant and potent inhibition of carrageenan- and dextran-induced paw edema in rats and marked decreases in the exudate volume and leukocyte migration in rats with carrageenan-induced pleurisy, the vascular permeability increase induced by intraperitoneal acetic acid, and the croton oil-induced topical ear edema in mice. On the other hand, the EEEm was not active in the test model of cotton pellet-induced granuloma in rats. Phytochemical analysis with E. macrophyllus leaves revealed the presence of triterpenoids, steroids, flavones, flavonols, and xanthones. Two flavonoids were isolated from the ethyl acetate fraction and identified as isovitexin and vitexin. Our results support the traditional use of E. macrophyllus leaves in the treatment of acute inflammatory conditions

Optimal Risk-Based Inspection Planning for Offshore Wind Turbines

José G. Rangel-Ramírez,John D. Sørensen 한국강구조학회 2008 International Journal of Steel Structures Vol.8 No.4

Wind turbines for electricity production have increased significantly the last years both in production capability and size. This development is expected to continue also in the coming years. The support structure for offshore wind turbines is typically a steel structure consisting of a tower and monopile, tripod or jacket type foundation. Monopiles are at present the most typical foundation, but tripods and jackets are expected to be used in the future at larger water depths. The support structures are facing deterioration processes such as fatigue and corrosion. To ‘control’ this deterioration, inspection and maintenance activities are developed. This paper considers aspects of inspection and maintenance planning of fatigue prone details in jacket and tripod types of wind turbine support structures. Based on risk-based inspection planning methods used for oil & gas installations, a framework for optimal inspection and maintenance planning of offshore wind turbines is presented. Special aspects for offshore wind turbines are considered: usually the wind loading are dominating the wave loading, wake effects in wind farms are important and the reliability level is typically significantly lower than for oil & gas installations. An illustrative example is presented. As part of the results, inspection times are calculated, showing that earlier inspections are needed at in-the-wind farm sites due to the increase of fatigue coming from wake turbulence.

Labial Adhesion Secondary to Lichen Sclerosus Masked by Vulvar Hailey–Hailey Disease

Elizabeth Suárez-Marquez,Luis Fernando Garcia-Rodriguez,Lucia Treviño-Rangel,María D. Guerrero-Putz 대한폐경학회 2022 대한폐경학회지 Vol.28 No.3

Labial adhesions in postmenopausal women are caused by various inflammatory processes in the context of estrogen deficiency. Lichen sclerosus (LS) is a chronic, progressive condition characterized by idiopathic epithelial thinning of the anogenital region with symptoms of significant pruritus, discomfort, and dyspareunia. Early diagnosis and treatment of LS can prevent disease progression, leading to labial adhesions and malignancy. We present an 84-year-old woman with long-standing vulvar Hailey–Hailey disease who developed labial adhesions. Clinical examination with vulvar biopsy revealed histopathological findings consistent with LS. Surgical separation of the labia by blunt dissection was then performed, and clobetasol ointment and vaginal dilatators were postoperatively prescribed. This resulted in a significant improvement in her symptoms. This is the first reported case of LS in a patient with Hailey–Hailey disease.

Steady-State and Transient Response Analysis of DSSC Based on Electron Diffusion Coefficient and Chemical Capacitance

J. C. Gallegos,J. Manriquez,R. Rodriguez,S. Vargas,D. Rangel The Korean Electrochemical Society 2024 Journal of electrochemical science and technology Vol.15 No.2

A study of the transition from transitory state to steady state in DSSCs based on natural dyes is presented; cochineal was used as dye and Li⁺, Na⁺, and K⁺ were the ions added to the electrolyte. The photocurrent profiles were obtained as a function of time. Several DSSCs were prepared with different cations and their role and the transitory-to-steady transition was determined. A novel hybrid charge carrier source model based on the Heaviside function H(t) and the Lambert-Beer law, was developed and applied to analysis of the transient response of the output photocurrent. Additionally, the maximum effective light absorption coefficient α and the electronic extraction rate κ for each ion were determined: ${\alpha}_{Li^+,Na^+,K^+}\,=\,(0.486,\,0.00085,\,0.1126)\,cm^{-1}$, and also the electronic extraction rate ${\kappa}^{Li^+,Na^+,K^+}_{ext.}\,=\,(1410,\,19.07,\,19.69)\,cm\,s^{-1}$. The impedance model using Fick's second law was developed for carrier recombination to characterize the photocurrent.