Characterisation of acetogen formatotrophic potential using Eubacterium limosum.

Formate is a promising energy carrier that could be used to transport renewable electricity. Some acetogenic bacteria, such as Eubacterium limosum, have the native ability to utilise formate as a sole substrate for growth, which has sparked interest in the biotechnology industry. However, formatotrophic metabolism in E. limosum is poorly understood, and a system-level characterisation in continuous cultures is yet to be reported. Here, we present the first steady-state dataset for E. limosum formatotrophic growth. At a defined dilution rate of 0.4 d-1, there was a high specific uptake rate of formate (280 ± 56 mmol/gDCW/d; gDCW = gramme dry cell weight); however, most carbon went to CO2 (150 ± 11 mmol/gDCW/d). Compared to methylotrophic growth, protein differential expression data and intracellular metabolomics revealed several key features of formate metabolism. Upregulation of phosphotransacetylase (Pta) appears to be a futile attempt of cells to produce acetate as the major product. Instead, a cellular energy limitation resulted in the accumulation of intracellular pyruvate and upregulation of pyruvate formate ligase (Pfl) to convert formate to pyruvate. Therefore, metabolism is controlled, at least partially, at the protein expression level, an unusual feature for an acetogen. We anticipate that formate could be an important one-carbon substrate for acetogens to produce chemicals rich in pyruvate, a metabolite generally in low abundance during syngas growth. KEY POINTS: First Eubacterium limosum steady-state formatotrophic growth omics dataset High formate specific uptake rate, however carbon dioxide was the major product Formate may be the cause of intracellular stress and biofilm formation.

Transcriptional control of Clostridium autoethanogenum using CRISPRi.

Gas fermentation by Clostridium autoethanogenum is a commercial process for the sustainable biomanufacturing of fuels and valuable chemicals using abundant, low-cost C1 feedstocks (CO and CO2) from sources such as inedible biomass, unsorted and nonrecyclable municipal solid waste, and industrial emissions. Efforts toward pathway engineering and elucidation of gene function in this microbe have been limited by a lack of genetic tools to control gene expression and arduous genome engineering methods. To increase the pace of progress, here we developed an inducible CRISPR interference (CRISPRi) system for C. autoethanogenum and applied that system toward transcriptional repression of genes with ostensibly crucial functions in metabolism.

A Pan-Genome Guided Metabolic Network Reconstruction of Five Propionibacterium Species Reveals Extensive Metabolic Diversity.

Propionibacteria have been studied extensively since the early 1930s due to their relevance to industry and importance as human pathogens. Still, their unique metabolism is far from fully understood. This is partly due to their signature high GC content, which has previously hampered the acquisition of quality sequence data, the accurate annotation of the available genomes, and the functional characterization of genes. The recent completion of the genome sequences for several species has led researchers to reassess the taxonomical classification of the genus Propionibacterium, which has been divided into several new genres. Such data also enable a comparative genomic approach to annotation and provide a new opportunity to revisit our understanding of their metabolism. Using pan-genome analysis combined with the reconstruction of the first high-quality Propionibacterium genome-scale metabolic model and a pan-metabolic model of current and former members of the genus Propionibacterium, we demonstrate that despite sharing unique metabolic traits, these organisms have an unexpected diversity in central carbon metabolism and a hidden layer of metabolic complexity. This combined approach gave us new insights into the evolution of Propionibacterium metabolism and led us to propose a novel, putative ferredoxin-linked energy conservation strategy. The pan-genomic approach highlighted key differences in Propionibacterium metabolism that reflect adaptation to their environment. Results were mathematically captured in genome-scale metabolic reconstructions that can be used to further explore metabolism using metabolic modeling techniques. Overall, the data provide a platform to explore Propionibacterium metabolism and a tool for the rational design of strains.

Heterologous Production of 6-Deoxyerythronolide B in Escherichia coli through the Wood Werkman Cycle.

Polyketides are a remarkable class of natural products with diverse functional and structural diversity. The class includes many medicinally important molecules with antiviral, antimicrobial, antifungal and anticancer properties. Native bacterial, fungal and plant hosts are often difficult to cultivate and coax into producing the desired product. As a result, Escherichia coli has been used for the heterologous production of polyketides, with the production of 6-deoxyerythronolide B (6-dEB) being the first example. Current strategies for production in E. coli require feeding of exogenous propionate as a source for the precursors propionyl-CoA and S-methylmalonyl-CoA. Here, we show that heterologous polyketide production is possible from glucose as the sole carbon source. The heterologous expression of eight genes from the Wood-Werkman cycle found in Propionibacteria, in combination with expression of the 6-dEB synthases DEBS1, DEBS2 and DEBS3 resulted in 6-dEB formation from glucose as the sole carbon source. Our results show that the Wood-Werkman cycle provides the required propionyl-CoA and the extender unit S-methylmalonyl-CoA to produce up to 0.81 mg/L of 6-dEB in a chemically defined media.

Rare primary leiomyosarcoma of the internal jugular vein with cervical extravascular extension.

Leiomysarcoma of intravascular origin is a rare malignant tumour of the soft tissue. We present what is, to our knowledge, the first example of one that has arisen from the wall of the internal jugular vein.

Fenestrated internal jugular vein: a rare finding in neck dissection.

Fenestration of the internal jugular vein (IJV) is an extremely rare phenomenon. An 85-year-old woman was referred to our department with T2N0M0 squamous cell carcinoma of the right floor of the mouth. The patient underwent local resection, an ipsilateral modified type 3 radical neck dissection, and microsurgical reconstruction. During neck dissection, a fenestration was observed in the middle of the IJV. No structure passed through the fenestration. Such anatomical variations are rare, but clinicians and surgeons should be aware of them in order to avoid damage to the important vascular structures, especially if a neck dissection is performed.

Glass transition study in model food systems prepared with mixtures of fructose, glucose, and sucrose.

The glass transition temperature of model food systems prepared with several glucose/fructose/sucrose mass fractions was studied using differential scanning calorimetry (DSC). A distance-based experimental design for mixtures of 3 components was used to establish the proportion of sugars of the model systems. Thus, 32 compositions including individual sugars and sugar mixtures, both binary and ternary were prepared and analyzed. Thermograms showing the complete process of heating-cooling-reheating were used to determine the precise glass transition temperature during cooling (T(g)(c)) or reheating (T(g)(H) in amorphous sugars. The Scheffe cubic model was applied to experimental results to determine the influence of sugar composition on the glass transition temperature (P < 0.05). The final model proved to be appropriate (R(2) > 0.97, CV < 9%, model significance <0.0001) to predict the T(g) values of any dry mixture of amorphous fructose, glucose, and sucrose.

Actualización sobre el virus del papiloma humano como factor etiopatogénico y pronóstico en el carcinoma oral de células escamosas / Update on the human papilloma virus as a pathogenic and prognosis factors in squamous cell carcinoma of the oral cavity

El cáncer orofaríngeo ha experimentado un aumento de su incidencia durante los últimos 20 años en contraste con el ligero descenso global del carcinoma de células escamosas de cabeza y cuello. Dicho aumento se ha producido en un subgrupo de pacientes con unas características diferentes al perfil clínico habitual, fundamentalmente más jóvenes y con baja exposición a alcohol y tabaco. La relación entre el carcinoma de células escamosas y ciertas cepas del virus del papiloma humano no sólo es un hecho constatado en los últimos años, sino que además ha originado un cambio en el perfil molecular, epidemiológico y clínico. El objetivo de este artículo es aportar una amplia revisión bibliográfica realizada sobre los trabajos más recientes que relacionan el carcinoma de células escamosas oral con la infección por el virus del papiloma humano. Asimismo, pretendemos plantear las tendencias en su manejo clínico y la repercusión en el perfil epidemiológico que dicha infección está representando (AU)

The oropharyngeal cancer incidence has increased over the past 20 years in contrast to the slight overall decrease of squamous cell carcinoma of head and neck. This increase has occurred in a subgroup of patients with different characteristics to the usual clinical profile, mainly younger and low exposure to alcohol and smoke. The relationship between squamous cell carcinoma and certain strains of human papilloma virus is not only a fact in recent years, also caused a change in the molecular, epidemiological and clinical profile. The aim of this paper is to provide an extensive literature review on recent work linking oral squamous cell carcinoma with human papillomavirus infection. Also, try to create trends in clinical management and the impact on the epidemiological profile that the infection is representing (AU)

Predictability of the resonance frequency analysis in the survival of dental implants placed in the anterior non-atrophied edentulous mandible.

BACKGROUND: Dental primary implant stability is considered essential in the success of the osseointegration process. The recent advent of the resonance frequency analysis (RFA) seems to effectively measure primary implant stability, although its relationship with implant survival has to be further established. PATIENTS AND METHODS: Seventy patients with complete mandibular edentulism underwent dental implant rehabilitation by means of the placement of 68 dental implants within the interforaminal region and subsequent placement of an overdenture. Primary implant stability was measured by means of RFA and it was expressed in terms of implant stability quotient (ISQ) on the day of the implant insertion and at the time of the healing abutment placement in a conventional implant two-stage surgical procedure. RESULTS: Overall implant survival rate was 97.1% at the end of the follow-up period. The mean ISQ value for 3.75 and 4.25 mm diameter implants was 78.4 ± 5.46 and 80.83 ± 5.35 respectively, at the time of the implant placement; and 76.68 ± 4.34 and 78.22 ± 6.87 respectively, at the second surgical stage. No statistical differences were observed in relation to changes in mean ISQ value along the healing process. CONCLUSIONS: No statistical differences in terms of primary and secondary implant stability measured by RFA exists between 3.75 mm and 4.25 mm diameter implants in the conventional implant two-stage surgical procedure in patients with non-atrophied edentulous mandible being restored with an overdenture. Furthermore, no statistical association between RFA and the implant insertion torque was observed for endosseous dental implant placement at the first surgical stage.

Alveolar split osteotomy for the treatment of the severe narrow ridge maxillary atrophy: a modified technique.

Alveolar bone splitting and immediate implant placement have been proposed for patients with severe atrophy of the maxilla in the horizontal dimension. A new modification of the classical alveolar bone splitting for the treatment of the narrow ridge in the maxilla is provided. Thirty-three dental implants in eight consecutive patients were evaluated retrospectively following the described modified split-crest osteotomy. Inclusion criteria were: inadequate maxillary buccolingual dimension, 3-4mm of crestal width, and sufficient height from alveolar ridge tip to maxillary sinus floor. Primary stability was calculated using resonance frequency analysis (RFA). Alveolar bone height was measured in the panorex pre- and postoperatively. Histological bone examination was assessed following trephine bone harvesting during the second operation. Mean follow-up was 28.33 months. Bone regeneration of the inter-cortical gap occurred in 98% of implant sites (implant survival rate 100%). Mean implant stability quotient (ISQ) for the whole series of implants was 69.48. At the second operation, mean loss of the alveolar bone height was 0.542mm. Predictable results are obtained using the modified split-crest osteotomy. This technique provides an acceptable inter-cortical gap, decreases the risk of necrosis of the outer cortex, and provides a firm-wall box for the placement of particulate bone grafting.

Distracción osteogénica vertical de injerto microvascularizado de peroné para reconstrucción mandibular y optimización de la rehabilitación implantológica / Vertical distraction osteogenesis of microvascularised fibular grafts for mandibular reconstruction and optimisation of rehabilitation implantology

Introducción: En la actualidad, se considera que el injerto microvascularizado de peroné es la mejor opción de tratamiento para las reconstrucciones mandibulares de defectos óseos mayores de 6 cm. No obstante, debido a su limitada altura, presenta una importante desventaja en cuanto a la rehabilitación protésica, particularmente en aquellos casos de resecciones mandibulares parciales con una hemimandíbula contralateral dentada. Material y métodos: Presentamos un caso clínico de mixoma mandibular tratado mediante resección quirúrgica y reconstrucción mandibular primaria mediante injerto microvascularizado de peroné, al que se sometió a distracción osteogénica vertical para optimizar la posterior rehabilitación implantológica. Resultados: La discrepancia de altura se solucionó completamente y se colocaron tres implantes osteointegrados en el área distraída, lo cual permitió una rehabilitación protésica muy satisfactoria, tanto estética como funcionalmente. Conclusiones: La distracción osteogénica vertical de peroné constituye una excelente opción terapéutica para igualar la altura del peroné a la del reborde alveolar de la hemimandíbula dentada contralateral, tras la reconstrucción de defectos mandibulares extensos, de cara a una posterior rehabilitación implantológica, lo que permite llevar a cabo ésta con resultados, tanto funcionales como estéticos, muy satisfactorios. Además, no presenta los inconvenientes de otras técnicas empleadas en estos pacientes, como el peroné en doble barra (mayor dificultad técnica y mayor riesgo de trombosis en el pedículo) y el empleo de injertos “onlay” (morbilidad añadida en la zona de toma del injerto)(AU)

Introduction: Free vascularized fibular flap is considered the treatment of choice in mandibular reconstruction for extensive bone defects. But, when the reconstruction involves a dentate mandible, the fibula has the limit as it doesn’t offer sufficient bone height to restore the alveolar arch up to the occlusal plane. Therefore, the deficiency in bone height makes implant placement impractical. Materials and methods: We report a case of vertical distraction osteogenesis of a free vascularized fibula flap used to reconstruct a hemimandible after resection of an odontogenic myxoma. The distraction device was applied intraorally. Distraction of 0.5 mm per day was performed followed by 3 months of consolidation period. Results: The vertical discrepancy between the fibula and the native hemimandible was corrected. The increase of vertical bone height was stable and enabled placement of dental implants without any complications. Conclusions: We believe that vertical distraction osteogenesis of free vascularized flaps is a reliable technique that optimizes implant positioning for ideal prosthetic rehabilitation, after mandibular reconstruction following tumour surgery(AU)

La influencia de la superficie articular y la membrana sinovial en la evolución de pacientes afectos por bloqueo crónico de la articulación temporomandibular tratados mediante artroscopia / Influence of the joint surface and the synovial membrane on the evolution of patients affected by chronic temporomandibular joint block who were treated with arthroscopic surgery

Introducción: Se ha referido la artroscopia de la articulación temporomandibular (ATM)como una técnica efectiva en el tratamiento del bloqueo crónico (BC) articular. El propósitodel presente estudio es evaluar si el estado de la superficie articular y la membrana sinovial directamente visualizados por artroscopia pueden determinar el resultado posoperatorio de pacientes afectos por BC de la ATM. Pacientes y método: Doscientos cincuenta y siete de 500 pacientes (344 articulaciones) cumplieronlos criterios de inclusión para BC de la ATM. Para el presente estudio se seleccionaron 172 pacientes con afectación unilateral. Se eligieron los parámetros "sinovitis" y "condromalacia" para la evaluación de la membrana sinovial y la superficie articular, respectivamente. Se establecieron dos grupos de pacientes: a) pacientes con afectación leve: sinovitisgrados I/II más condromalacia I/II, y b) pacientes con afectación grave: sinovitis gradosIII/IV más condromalacia grados III/IV. Se eligieron el dolor y la máxima apertura oral(MAO) interincisal como variables dependientes. Todos los pacientes se revisaron de modo posoperatorio al mes, 3, 6, 12 y 24 meses. Se utilizó la prueba de la “t” de Student paramuestras pareadas para comparar los valores medios de dolor (escala visual analógica, EVA) y función (MAO), de modo preoperatorio y posoperatorio. Se utilizó la “t” de Student para muestras independientes para la comparación de los diferentes grupos establecidos.Se consideró estadísticamente significativo un valor de p <= 0,05. Resultados: Artroscópicamente se observó sinovitis grados I/II en 87 (50,58%) pacientes, y sinovitis grados III/IV en 72 (41,86%), mientras que se objetivó condromalacia grados I/IIen 66 (38,37%) pacientes y condromalacia grados III/IV en 54 (31,39%)...(AU)

Introduction: Arthroscopy of the temporomandibular joint (TMJ) has been considered aneffective technique to treat close lock (CL). The purpose of this study is to evaluate if thestatus of the joint surface and the synovial membrane directly seen via arthroscopy candetermine the post operative results of patients with chronic block of the TMJ. Patients and methods: Two hundred and fifty-seven out of the 500 patients (344 joints) met thecriteria for chronic block of the TMJ. One hundred and seventy-two patients with unilateralaffectation were selected for this study. Synovitis and chondromalacia are the parameters chosen to evaluate the synovitis membrane and joint surface, respectively. Two groups ofpatients were formed: a) patients with light affectation: level I/II synovitis and level I/II chondromalacia, and b) patients with severe affectation: level III/IV synovitis and level III/IV chondromalacia. The dependent variables were pain and interincisal maximum oralopening (MOO). All of the patients had post operative follow-up at 1, 3, 6, 12, and 24 months.The "t" Student test was used before and after surgery to match evidence to compare the average values of visual analogical scale (VAS) and function (MOO). The "t" Student test wasused for independent samples to compare the different groups that were established. Avalue of p <= 0.05 was considered statistically significant. Results: Level I/II synovitis was seen using arthroscopy in 87 (50.58%) patients, and level III/IV synovitis was seen in 54 (31.39%) of patients, while level I/II chondromalacia was observed in 66 (38.37%) patients and level III/IV chondromalacia was observed in 54 (31.39%).During the follow-up period a significant decrease in pain and a parallel increase in oral opening were observed after arthroscopy in patients affected by level I/II and III/IV synovitis and level I/II and III/IV chondromalacia (AU)

Síndrome de Gorlin-Goltz: serie de 7 casos / Gorlin-Goltz Syndrome. A 7 cases serie

El Síndrome Névico Basocelular (SNBC) o Síndrome de Gorlin-Goltz es un trastorno autosómico dominante, caracterizado principalmentepor carcinomas basocelulares, múltiples queratoquistes y anomalías esqueléticas.El presente trabajo revisa a este desconocido síndrome dada la importanciaque tiene para nosotros como especialistas. Presentamos un total desiete casos recogidos por el Servicio Cirugía Oral y Maxilofacial desde 1992al 2008, con seguimiento medio de 10 años, determinamos la frecuencia delas características clínicas en nuestra serie de SNBC y el manejo terapéuticode las mismas(AU)

Nevoid Basal Cell Carcinoma Syndrome (NBCSS) or Gorlin-Goltz Syndrome is an autosomal dominant disorder principallycharacterized by cutaneous basal cell carcinomas, multiplekeratocysts and skeletal anomalies. This report reviews currentknowledge of this disorder that is important to us as specialists. Theauthors reviewed seven case files from the Department of Oral andMaxillofacial Surgery of H. U. La Princesa from 1992-2008. Theaverage follow up was 10 years; we determine the frequency of theclinical features and treatment in our series of NBCCS(AU)

Lesión linfoepitelial quística benigna de glándula parótida en paciente con infección por VIH / Lesion of benign lymphoepithileal cyst of the parotid gland in a patient infected with HIV

No disponible

Colgajo frontal. Método sencillo en la reconstrucción de defectos cutáneos nasales extensos / Forehead flap. A simple method for the reconstruction of extensive nasal skin defects

Las aplicaciones del colgajo frontal en la cirugía de los defectosnasales son destacables, pues la práctica totalidad de las sub-unidades nasales,incluidos el vestíbulo nasal, el reborde alar y la columela pueden serreconstruidos satisfactoriamente. Su técnica de tallado es sencilla y las complicacionesde la zona donante escasas. El color de la piel, su textura y la posibilidadde obtener una amplia cantidad de tejido, con o sin expansión tisularprevia, lo hacen de primera elección en la reconstrucción de defectos cutáneosnasales extensos. Referimos muestra experiencia reciente en el uso deeste colgajo y revisamos el estado del arte actual en el empleo del mismo(AU)

The use of the forehead flap in the surgery of nasal defectsis noteworthy because almost all of the nasal subunits, includingthe nasal vestibule, alar margin, and columella nasi can bereconstructed satisfactorily. The cutting technique is simple andthere are few donor zone complications. The color of the skin, itstexture, and the feasibility of obtaining a large amount of tissue,with or without previous tissue expansion, make forehead flaps thetechnique of choice in the reconstruction of extensive nasal skindefects. We report our recent experience with this flap and we reviewthe current state-of-the-art in the use of this flap(AU)

Transoral endoscopic-assisted management of subcondylar fractures in 17 patients: an alternative to open reduction with rigid internal fixation and closed reduction with maxillomandibular fixation.

The authors evaluate the results of transoral endoscopic-assisted open reduction and miniplate fixation of subcondylar fractures. Seventeen patients were treated from August 2005 to April 2007. Inclusion criteria were: adult patients, inability to achieve adequate occlusion with closed reduction, dislocation of the condylar fragment between 10 and 45 degrees , and 2-mm inter-fragment overlapping. Regular panoramic radiographs were taken postoperatively. Transbuccal incisions were used to place the screws for fixation in 15 patients. Pure intraoral access and angulated drills and screwdrivers were used in 2 patients. The condyle was placed into the condylar fossa in all cases. No damage to the facial nerve was observed. No visible scars were present. Mean surgical time was 80.36 minutes. Transitory hyposthesia was observed in 3 cases. Adequate reduction and consolidation of the fracture was achieved in 16 patients. No condylar reabsortion was present at the end of the follow-up period. The authors consider that transoral endoscopic-assisted open reduction constitutes a valid alternative to a transcutaneous approach for the reduction and fixation of subcondylar fractures in selected cases. It provides the benefits of open reduction and internal fixation without the potential complications. Advice is given on how to achieve adequate reduction and stability of the proximal fragment.

Online monitoring of Mezcal fermentation based on redox potential measurements.

We describe an algorithm for the continuous monitoring of the biomass and ethanol concentrations as well as the growth rate in the Mezcal fermentation process. The algorithm performs its task having available only the online measurements of the redox potential. The procedure combines an artificial neural network (ANN) that relates the redox potential to the ethanol and biomass concentrations with a nonlinear observer-based algorithm that uses the ANN biomass estimations to infer the growth rate of this fermentation process. The results show that the redox potential is a valuable indicator of the metabolic activity of the microorganisms during Mezcal fermentation. In addition, the estimated growth rate can be considered as a direct evidence of the presence of mixed culture growth in the process. Usually, mixtures of microorganisms could be intuitively clear in this kind of processes; however, the total biomass data do not provide definite evidence by themselves. In this paper, the detailed design of the software sensor as well as its experimental application is presented at the laboratory level.

Sialometaplasia necrotizante / Necrotizing sialometaplasia

No disponible

No disponible