Dynamic genome-based metabolic modeling of the predominant cellulolytic rumen bacterium Fibrobacter succinogenes S85.

Fibrobacter succinogenes is a cellulolytic bacterium that plays an essential role in the degradation of plant fibers in the rumen ecosystem. It converts cellulose polymers into intracellular glycogen and the fermentation metabolites succinate, acetate, and formate. We developed dynamic models of F. succinogenes S85 metabolism on glucose, cellobiose, and cellulose on the basis of a network reconstruction done with the automatic reconstruction of metabolic model workspace. The reconstruction was based on genome annotation, five template-based orthology methods, gap filling, and manual curation. The metabolic network of F. succinogenes S85 comprises 1,565 reactions with 77% linked to 1,317 genes, 1,586 unique metabolites, and 931 pathways. The network was reduced using the NetRed algorithm and analyzed for the computation of elementary flux modes. A yield analysis was further performed to select a minimal set of macroscopic reactions for each substrate. The accuracy of the models was acceptable in simulating F. succinogenes carbohydrate metabolism with an average coefficient of variation of the root mean squared error of 19%. The resulting models are useful resources for investigating the metabolic capabilities of F. succinogenes S85, including the dynamics of metabolite production. Such an approach is a key step toward the integration of omics microbial information into predictive models of rumen metabolism. IMPORTANCE F. succinogenes S85 is a cellulose-degrading and succinate-producing bacterium. Such functions are central for the rumen ecosystem and are of special interest for several industrial applications. This work illustrates how information of the genome of F. succinogenes can be translated to develop predictive dynamic models of rumen fermentation processes. We expect this approach can be applied to other rumen microbes for producing a model of rumen microbiome that can be used for studying microbial manipulation strategies aimed at enhancing feed utilization and mitigating enteric emissions.

Do follicle-stimulating hormone receptor polymorphisms in infertile men influence intracytoplasmic sperm injection outcomes? A prospective cohort study.

The follicle-stimulating hormone (FSH) and its receptor regulate the quantity and quality of spermatozoa production. Several studies have analyzed the effect of single nucleotide polymorphisms (SNPs) in exon 10 of the FSH receptor (FSHR) on basic semen parameters without yet reaching a firm consensus. The aim of this study was to evaluate the effect of p.Thr307Ala and p.Asn680Ser polymorphisms in exon 10 of the FSHR gene, in infertile men, on intracytoplasmic sperm injection (ICSI) outcomes. This study was conducted between March 2019 and February 2020 on infertile couples undergoing ICSI at Al Hadi Laboratory and Medical Center, Lebanon. Couples with severe infertility factors that may impair gametogenesis/embryogenesis (e.g. advanced maternal age, premature ovarian failure, underwent gonadotoxic treatments, etc.) were excluded from the study. Semen and blood samples were collected from infertile men on the day of oocyte collection. Infertile men (n = 173) were screened for FSHR variants using polymerase chain reaction-restriction fragment length polymorphism. Moreover, fertilization rates, embryo quality, and pregnancy outcomes were evaluated. Higher sperm concentrations were found in the p.Thr307Ala group than the p.Thr307Thr (P < 0.01) and p.Ala307Ala (P < 0.05) groups. Furthermore, fertilization rate was significantly lower in the p.Ala307Ala genotype than in the p.Thr307Thr genotype (P < 0.05). We showed that FSHR variants in infertile men undergoing ICSI could affect sperm concentration, motility, and fertilization rates. Therefore, it will be important to confirm these results in further studies using a larger sample size.

Necrosis auricular bilateral secundaria a cocaína adulterada con levamisol / Bilateral auricular necrosis secondary to levamisole-adulterated cocaine

La cocaína es la droga estimulante ilegal más consumida en Europa, siendo España uno de los países con mayor consumo. La adulteración de la cocaína con levamisol, de nueva aparición, ha provocado casos de neutropenia severa y vasculitis necrotizante. Presentamos el caso de un paciente que tras consumo de cocaína adulterada con levamisol presenta clínica sugestiva de necrosis bilateral de pabellón auricular. La adulteración de la cocaína con levamisol puede inducir una reacción inmunológica de tipo vasculitis causando necrosis cutánea irreversible si no cesa su uso. El tratamiento con aspirina y corticoides es aún controvertido. A pesar de ser una entidad rara, el conocimiento de este tipo de lesión es importante en nuestro medio para un precoz diagnóstico y tratamiento. (AU)

Cocaine is one of the most consumed ilegal drugs in Europe, with Spain heading the list. The recent appearance of levamisol-adulterated cocaine has led to new cases of severe neutropenia and necrotizing vasculitis among consumers. We report a case of a patient with bilateral auricular necrosis after levamisole-adulterated cocaine. Adulteration of cocaine with levamisole can lead to inmunological vasculitis-like response causing irreversible skin nerosis if continuosly consumed. Aspirin and corticotherapy treatment are still controversial. Although skin necrosis secondary to levamisole-adulterated cocaine is still unusual, diagnosis and early treatment of this kind of entity is crucial. (AU)

Graphene field effect transistor scaling for ultra-low-noise sensors.

The discovery of the field effect in graphene initiated the development of graphene field effect transistor (FET) sensors, wherein high mobility surface conduction is readily modulated by surface adsorption. For all graphene transistor sensors, low-frequency 1/f noise determines sensor resolution, and the absolute measure of 1/f noise is thus a crucial performance metric for sensor applications. Here we report a simple method for reducing 1/f noise by scaling the active area of graphene FET sensors. We measured 1/f noise in graphene FETs with size 5 µm × 5 µm to 5.12 mm × 5.12 mm, observing more than five orders of magnitude reduction in 1/f noise. We report the lowest normalized graphene 1/f noise parameter observed to date, 5 × 10-13, and we demonstrate a sulfate ion sensor with a record resolution of 1.2 × 10-3 log molar concentration units. Our work highlights the importance of area scaling in graphene FET sensor design, wherein increased channel area improves sensor resolution.

Selective ion sensing with high resolution large area graphene field effect transistor arrays.

Real-time, high resolution, simultaneous measurement of multiple ionic species is challenging with existing chromatographic, spectrophotometric and potentiometric techniques. Potentiometric ion sensors exhibit limitations in both resolution and selectivity. Herein, we develop wafer scale graphene transistor technology for overcoming these limitations. Large area graphene is an ideal material for high resolution ion sensitive field effect transistors (ISFETs), while simultaneously enabling facile fabrication as compared to conventional semiconductors. We develop the ISFETs into an array and apply Nikolskii-Eisenman analysis to account for cross-sensitivity and thereby achieve high selectivity. We experimentally demonstrate real-time, simultaneous concentration measurement of K+, Na+, [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and Cl- with a resolution of [Formula: see text] concentration units. The array achieves an accuracy of  ±0.05 log concentration. Finally, we demonstrate real-time ion concentration measurement in an aquarium with lemnoideae lemna over three weeks, where mineral uptake by aquatic organisms can be observed during their growth.

Reconstrucción de defectos bimaleolares complejos con colgajos quiméricos microquirúrgicos en doble isla / Reconstruction of complex bimallelolar defects with double island microsurgical chimeric flaps

Introducción y Objetivo. Las fracturas de tobillo son unas de las más frecuentemente atendidas en urgencias por los cirujanos ortopédicos. El riesgo de dehiscencia e infección de la herida quirúrgica como consecuencia de la edematización, alteración en el proceso de cicatrización y daño local de los tejidos, puede provocar complejos defectos que afecten a ambos maléolos, necesitando abordaje ortoplástico. Dada la estructura tridimensional e irregular de las lesiones bimaleolares, es difícil cubrirlas con un solo colgajo microquirúrgico o pediculado, siendo necesaria en muchas ocasiones la utilización de dos islas cuyos ejes vasculares tengan cierta independencia en cuanto a movilidad. Presentamos 3 casos clínicos recogidos en el Hospital General Universitario de Alicante (España), para describir la cobertura de grandes defectos bimaleolares utilizando colgajos quiméricos intrínsecos en doble isla. Material y Método. Los colgajos se basaron en los sistemas de la arteria toracodorsal, con paleta cutánea y muscular, y de la arteria circunfleja femoral lateral, uno de ellos con paleta cutánea y muscular; y otro con doble paleta cutánea. Resultados. La supervivencia de los colgajos fue del 100%. El seguimiento postoperatorio amplio, de entre 2 y 8 años, obtuvo cobertura de calidad, sin dehiscencia, infección local o exposición ósea. Los pacientes no presentaron déficits funcionales durante el seguimiento, y los resultados estéticos fueron aceptables. Conclusiones. Este trabajo es uno de los pocos existentes en la bibliografía que trata de manera monográfica el abordaje microquirúrgico de las pérdidas de sustancia bimaleolares, mostrando una estrategia eficaz en la cobertura de una región tridimensionalmente difícil de cubrir con una sola anastomosis arterial y venosa (un único colgajo quimérico) (A)

Background and Objective. Ankle fractures are one of the most frequently treated by orthopedic surgeons in emergency. The risk of dehiscence and infection of the surgical wound as a result of edema, impaired wound healing and local tissue damage , may cause complex defects affecting both malleoli, requiring an ortho-plastic approach. Because of irregular three-dimensional structure of bimalleolar injuries, it is difficult to cover them with an only microsurgical or pedicled flap, requiring often the use of two islands which vascular axes have independence in terms of mobility. We present 3 clinical cases collected at the University General Hospital of Alicante (Spain) to describe the coverage of large bimalleolar defects using intrinsic chimeric flaps with double island. Methods. Flaps were based on the thoracodorsal artery system, with skin and muscle palette, and on the lateral circumflex femoral artery system, one with skin and muscle palette and another with a double skin palette. Results. The survival of the flaps was 100%. The postoperative follow-up was wide, between 2 and 8 years, obtaining a quality coverage without finding dehiscence, local infection or exposure. Patients did not present functional deficits during the follow-up with acceptable aesthetic results. Conclusions. This work is one of the few papers existing in the literature that treats in a monographic way the microsurgical treatment of bimalleolar defects, showing an effective strategy in the coverage of a difficult three-dimensional region using a single arterial and venous anastomosis (a single chimeric flap) (AU)