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Introduction Tissue engineering (TE) has the capacity to design structures very similar to native tissues in order to restore, maintain or improve their biological functions. Silk fibroin (SF) is a natural protein that has been used in a wide variety of TE applications. Each SF structure has different mechanical and biological characteristics depending on the morphology and methodology employed. Methods Bombyx mori silkworm cocoons were extracted and processed to obtain SF. Subsequently, films, porous membranes, and electrospun membranes were designed using doctor blade, salt leaching, and electrospinning methodologies, respectively. Furthermore, electrospun SF membranes were developed according to the direction of the strands, obtaining membranes that were oriented as well as with random orientation. All these morphologies were subjected to mechanical, cytotoxicity and degradation studies. Results The most fragile SF structures were the films and the porous membranes, which underwent a maximum modification of approximately 5% with respect to their original size. However, electrospun membranes underwent a change in size of more than 20%. All SF morphologies had biocompatibility values close to 100%. Finally, there was a degradability between 3–5% at 4 weeks in all structures. Conclusions SF has very good mechanical characteristics when designed by electrospinning techniques. Although SF is biocompatible, there is a degradation of the material, which may affect the mechanical properties of the designed structure.

The work carried out focuses on the importance and characteristics of bioplastics, which is why the bibliographic sources consulted recall that the plastic manufactured from biopolymers has been increasing due to its practicality and in supporting the reduction of pollution of solid waste worldwide. Viable alternatives are currently being sought to replace packaging and coatings made from non-renewable raw materials, as these cause millions of tons of waste each year, damaging the environment. The production process of biodegradable plastics has a certain resemblance to the production of conventional plastics, it consists of a mixer of raw materials with additional components, for a subsequent blowing and sealing, passing through a quality control. One of the problems with conventional plastics is that they are manufactured from raw materials obtained from non-renewable resources, which each day becomes scarcer and therefore more expensive. Also the problem of persistence in the medium for very long times, which cause them to occupy space in sanitary landfills, which are causing problems in the country due to lack of space.

Digital interventions are important tools to promote mental health literacy among university students. “Depression in Portuguese University Students” (Depressão em Estudantes Universitários Portugueses, DEEP) is an audiovisual intervention describing how symptoms can be identified and what possible treatments can be applied. The aim of this study was to evaluate the impact of this intervention. A random sample of 98 students, aged 20–38 years old, participated in a 12-week study. Participants were recruited through social media by the academic services and institutional emails of two Portuguese universities. Participants were contacted and distributed into four study groups (G1, G2, G3 and G4): G1 received the DEEP intervention in audiovisual format; G2 was given the DEEP in text format; G3 received four news articles on depression; G4 was the control group. A questionnaire was shared to collect socio-demographic and depression knowledge data as a pre-intervention method; content was then distributed to each group following a set schedule; the depression knowledge questionnaire was then administered to compare pre-intervention, post-intervention and follow-up literacy levels. Using the Scheffé and Least Significant Difference (LSD) multiple comparisons test, it was found that G1, which received the DEEP audiovisual intervention, differed significantly from the other groups, with higher depression knowledge scores in post-intervention stages. The DEEP audiovisual intervention, compared to the other formats used (narrative text format; news format), proved to be an effective tool for increasing depression knowledge in university students.

This chapter describes the pectin production process from citrus residues. It discusses the importance of essential oils removal before processing through steam distillation, hydrodistillation, or solvent extraction. Also, it presents different extraction methods (acid hydrolysis, microwave-assisted acid hydrolysis, and hydrodistillation) that have been employed and different solvents that can be used for its purification. Since all these processing parameters can affect the final pectin yield and quality, a discussion is made on which processing options and conditions could be used based on recently reported data. The best operational conditions based on the percentages of pectin recovery and their relationship with quality parameters, such as the galacturonic acid content and degree of esterification are presented. Finally, a discussion is made regarding the opportunities for its integration under the biorefinery concept that could help to enhance several economic and environmental aspects of the process.

INTRODUCTION This study presents the first steps and results towards the development of a system for predicting the quality of surgical performance and workload in laparoscopic training. MATERIAL AND METHODS Surgeons wore a smartwatch which recorded their heart rate and hand motion during each laparoscopic procedure. Data was then correlated with both the Surgery Task Load Index (SURG-TLX) subjective questionnaire and the Global Operational Assessment of Laparoscopic Skills (GOALS) objective evaluation tool. Statistical analysis was conducted in order to study the relationship between parameters and to compare the results according to the surgeons’ level of experience. RESULTS Nine laparoscopic surgeons participated in this study, five gynecologists and four digestive surgeons. Gynecological surgeons showed a positive correlation between their level of experience, heart rate, hand motion, and GOALS score, except for bimanual dexterity. The reduction in the variability of hand accelerations led to improved tissue handling. Digestive surgeons showed a negative correlation between their level of experience and the reported temporal demand and complexity of the procedure. Novice digestive surgeons reported increased workload during surgery, mainly in mental, physical, and temporal workload. In both surgical specialties, it was observed that reduction in surgical workload was associated with improved GOALS score. CONCLUSIONS Preliminary results showed that bimanual dexterity is independent of the experience of gynecological surgeons. During laparoscopic surgical procedures, reduced variability in hand accelerations leads to better tissue manipulation. In addition, in gynecological and upper gastrointestinal procedures, reduced surgical workload is associated with improved surgical performance.

Due to its technological applications, such as CO2 capture, CaO carbonation kinetics has been extensively studied using a wide array of methods and experimental conditions. A complete understanding of carbonation kinetics is key to optimizing the operating conditions as well as to correctly design the carbonation reactor. However, there is yet no consensus on the reaction model and kinetic parameters that can best describe the CaO carbonation reaction. For instance, the value of the activation energy proposed in different works can vary up to 300%. In this work, we demonstrate that the strong influence of the thermodynamic equilibrium on CaO carbonation kinetics demands careful control of the experimental conditions to obtain meaningful kinetic parameters. Specifically, we explore the influence of three experimental parameters on carbonation kinetics: the gas flow rate, the CO2 partial pressure and the time required to fill the reactor after a gas change. We demonstrate that disregarding these aspects may lead to bogus conclusions on reaction kinetics, which could partly explain the considerable discrepancies found in the literature. The conclusions of this work are not only applicable to the process and experimental setup studied here but also to any study that involves the use of gas flow to drive a reaction

Highlights • Metabolites extracted from Cordyceps nidus induce laccase activity of Pleurotus ostreatus. • The composition of the substrate where Cordyceps nidus is grown induces the production of different bioactive compounds. • Laccase activity of P. ostreatus is improved four times over the control condition when C. nidus’ extracts are supplemented. • The addition of C. nidus’ extracts to the cultures of P. ostreatus improves the production of fermentable sugars., Laccases are ligninolytic enzymes produced by different microorganisms, especially by fungi such as the white-rot fungus Pleurotus ostreatus. Chemical inductors have been used to promote laccase secretion due to the application of these enzymes in lignocellulosic biomass pretreatment. Cordyceps nidus ANDES-F1080 was previously described as a source of bioactive compounds that could influence the enzymatic production system of other fungi. For that reason, this study evaluates the effect of C. nidus’ ANDES-F1080 extracts on the laccase activity of P. ostreatus ANDES-F515. To achieve this objective, C. nidus ANDES-F1080 was grown in four different substrates: two artificial-based and two natural-based culture media. Metabolites were extracted from C. nidus ANDES-F1080 using water and methanol as solvents. Biochemical characterization of these extracts was performed to complement the analysis of their effect on laccase activity. Our results revealed an enhancement on the laccase activity of P. ostreatus ANDES-F515 grown in natural-based cultures when C. nidus’ ANDES-F1080 extracts were supplemented. The best laccase activities registered values around 10,575 ± 813 U·L−1.

Laprise et al. (2019) observed a positive association between oral sex practices and oropharyngeal cancers (OPC) among HPV-negative individuals. Because oral HPV infections are likely to be transmitted through oral sex, these results are counterintuitive. We revisit Laprise et. al's analysis with the objective of estimating the impact of misclassification of HPV infection on the association between oral sex practices and OPC.Data were drawn from the Head and Neck Cancer (HeNCe) Life study, a hospital-based case control study of head and neck cancer with frequency-matched controls by age and sex from 4 major referral hospitals in Montreal, Canada. We included only OPC cases (n = 188) and controls (n = 429) and used predictive value weighting, under differential and non-differential scenarios, to evaluate the misclassification. Subsequently, we used logistic regression and 95% confidence intervals to estimate the association between oral sex practice and OPC among HPV-negative individuals.Our results showed that the previously reported association between oral sex practices and OPC among HPV-negative individuals was attenuated or nullified both under differential and non-differential scenarios.The association between oral sex practice and OPC could be explained by biases in the data (e.g., HPV mediator misclassification). Our results highlight the need for widespread adoption of Quantitative Bias Analysis in oral health research.

White-rot fungi represent an outstanding alternative for valorizing fruit residues due to their ability to decompose structural carbohydrates and other bioactive compounds abundant in fruit waste. Enzymes produced by these fungi are responsible for the biological pretreatment process carried out by oxidases and hydrolases, resulting in the degradation of structural carbohydrates and lignin. This work reviews and compares reported data on Solid-State Fermentation (SSF) and Submerged Fermentation (SmF) using various strains from the genus Pleurotus for the biological pretreatment of fruit residues. SSF could be the best cultivation strategy due to its similarity to the natural growth conditions of fungi on wood substrates. Nonetheless, SmF has advantages if the process is to be scaled at industrial level. Further research will be required to determine adequate growth conditions of Pleurotus spp. on fruit residues, including the study of relevant parameters of the process (i.e., fungi strains, substrates, additives).

The structural variability of two series of Mg2+- and Zn2+- 2-hydroxyphosphonoacetates have been studied in the range of 25–80°C and 95% relative humidity in order to correlate the structure with the proton conductivity properties. In addition to selected previously reported 1D, 2D and 3D materials, a new compound, KZn6(OOCCH(OH)PO3)4(OH)·5H2O (KZn6-HPAA-3D), has been prepared and thoroughly characterized. The crystal structure of this solid, solved ab initio from synchrotron X-ray powder diffraction data, consists of a negatively charged 3D framework with K+ ions, as compensating counterions. It also contains water molecules filling the cavities in contrast to the potassium-free 3D anhydrous NH4Zn(OOCCH(OH)PO3) (NH4Zn-HPAA-3D). In the range of temperature studied, the 1D materials exhibit a 1D→2D solid-state transition. At 80°C and 95% RH, the 2D solids show moderate proton conductivities, between 2.1×10−5 S·cm−1 and 6.7×10−5 S·cm−1. The proton conductivity is slightly increased by ammonia adsorption up to 2.6×10−4 S·cm−1, although no ammonia intercalation was observed. As synthesized KZn6-HPAA-3D exhibits a low proton conductivity, 1.6×10−6 S·cm−1, attributed to the basic character of the framework and a low mobility of water molecules. However, this solid transforms to the 2D phase, Zn(OOCCH(OH)PO3H)·2H2O, upon exposure to dry HCl(g), which enhances the proton conductivity with respect to the as-synthesized 2D material (4.5×10−4 S·cm−1). On the other hand, NH4Zn-HPAA-3D exhibited a higher proton conductivity, 1.4×10−4 S·cm−1, than the K+ analog.

Laccases are ligninolytic enzymes produced by different microorganisms, especially by fungi such as the white-rot fungus Pleurotus ostreatus. Chemical inductors have been used to promote laccase secretion due to the application of these enzymes in lignocellulosic biomass pretreatment. Cordyceps nidus ANDES-F1080 was previously described as a source of bioactive compounds that could influence the enzymatic production system of other fungi. For that reason, this study evaluates the effect of C. nidus’ ANDES-F1080 extracts on the laccase activity of P. ostreatus ANDES-F515. To achieve this objective, C. nidus ANDES-F1080 was grown in four different substrates: two artificial-based and two natural-based culture media. Metabolites were extracted from C. nidus ANDES-F1080 using water and methanol as solvents. Biochemical characterization of these extracts was performed to complement the analysis of their effect on laccase activity. Our results revealed an enhancement on the laccase activity of P. ostreatus ANDES-F515 grown in natural-based cultures when C. nidus’ ANDES-F1080 extracts were supplemented. The best laccase activities registered values around 10,575 ± 813 U·L−1.

Las heridas por arma de fuego de velocidad alta o intermedia, provocan importantes pérdidas de tejido óseo y blando. El tratamiento diferido de estos casos (tratamiento reconstructivo) requiere el aporte de tejido sano de regiones distantes mediante técnicas microquirúrgicas en la mayoría de las ocasiones. Exponemos la utilidad del colgajo osteocutáneo escapular (COE) para la reconstrucción de defectos óseos mandibulares laterales con amplio defecto cutáneomucoso. Citamos detalles técnicos de la realización del colgajo ilustrados con la presentación de un caso clínico de un varón de 19 años con herida por arma de fuego en tercio inferior de la región lateral izquierda. Pérdida ósea del cuerpo mandibular y cutánea de la mejilla y región yugal ipsilateral. El tratamiento inicial consistió en traqueotomía, desbridamiento de tejidos desvitalizados, ferulización dentaria, bloqueo intermaxilar, colocación de placa de reconstrucción mandibular y colgajo de avance cervico-facial para cierre del defecto cutáneo. La necrosis del colgajo de avance cervicofacial produjo comunicación orofacial. La retracción cicatricial limitó la apertura oral a 0,8 cm. De forma diferida se procedió a colgajo osteomiocutáneo escapular-paraescapular del brazo izquierdo para reconstrución mandibular y de partes blandas intra y extraorales. Resultados satisfactorios estética y funcionalmente. Complicaciones producidas: fístula salival, desinserción del brazo largo del tríceps, y dehiscencia de herida de zona donante escapular que necesitó intervención para cierre mediante colgajo local.Firearm wounds caused by high-velocity projectiles cause enormous losses of bone and soft tissue. The deferred treatment of these cases (delayed reconstruction) in most cases requires the transfer of free tissue from other areas of the body. The use of scapular and parascapular free flaps with scapular bone for the reconstruction of large lateral mandibular defects with extensive soft-tissue avulsion is reported. The technical details of a free flap are offered with illustrations in the case report of a 19-year-old male who was shot at close range in the lower third of the left lateral face. Avulsion of the left mandibular body and soft tissue occurred in the region from the cheek to the oral commissure. The initial treatment was tracheostomy, cleaning of necrotic and devitalized tissues, wiring of a mandible-to-maxilla arch bar and intermaxillary fixation, rigid fixation with a reconstructive mandibular plate, and a regional cervical flap to close the skin wound. The cervical flap was lost and a postoperative oral-cervical fistula appeared. Scar contraction limited the mouth opening to 0.8 cm. In deferred treatment, a scapular and parascapular free flap with scapular bone from the left shoulder was used to reconstruct the mandibular and intraoral-facial soft-tissue defects. The aesthetic and functional results were optimal. Some complications occurred: postoperative salivary fistula, deinsertion of the long head of the brachial triceps, and scapular wound dehiscence, which will be closed surgically with a local flap.

This work was designed to study the effect of different lipid sources on the activities of lipoprotein lipase and lipogenic enzymes in adipose tissue from rats fed ad libitum or energy-controlled diets. Male Wistar rats were fed diets containing 40% of energy as fat (olive oil, sunflower oil, palm oil or beef tallow), for 4 wk. Under ad libitum feeding no differences were found among dietary fat groups in final body weight, adipose tissue weights and total body fat. Under energy-controlled feeding, despite isoenergetic intake, rats fed the beef tallow diet gained significantly less weight than rats fed the other three diets. Beef tallow fed rats showed the lowest values for adipose tissue weights and total body fat. When rats had free access to food no effect of dietary lipid source on lipogenic enzyme activities was found. In contrast, under energy-controlled feeding rats fed the beef tallow diet showed significantly higher activities of glucose-6-phosphate dehydrogenase and fatty acid synthase than rats fed the other three diets. Heparin-releasable lipoprotein lipase activity in perirenal and subcutaneous adipose tissues was not different among rats fed olive oil, safflower oil, palm oil or beef tallow. When comparing both adipose tissue anatomical locations, significantly higher activities were found in subcutaneous than in perirenal fat pad independently of dietary fat. In conclusion, under our experimental protocol, lipogenesis in rat adipose tissue does not seem to be affected by dietary fat type.

El seudoaneurisma del seno de Valsalva constituye una afeccion aortica sumamente infrecuente; por encima, incluso, de los aneurismas congenitos. Su etiologia engloba desde casos traumaticos e infecciosos hasta otros de naturaleza idiopatica. Presentamos el caso de un varon de 74 anos, con varios ingresos cardiologicos previos por infarto de miocardio y clinica sincopal y de dolor toracico atipico, en el que las pruebas diagnosticas angiograficas y de resonancia magnetica pusieron de manifiesto un seudoaneurisma de genesis espontanea a nivel del seno coronariano izquierdo. Asociaba, ademas, dilatacion de aorta ascendente e insuficiencia aortica grave sobre una valvula bicuspide. La correccion se llevo a cabo mediante sustitucion valvular aortica y de aorta ascendente sinusal y tubular proximal mediante tubo valvulado de dacron (protesis biologica), con buen resultado quirurgico. En el periodo postoperatorio preciso implantacion de marcapasos definitivo por fibrilacion auricular (FA) con bloqueo auriculoventricular (AV) completo. El paciente se halla, en la actualidad y tras 8 meses de seguimiento, asintomatico.

Objetivo El objetivo de no danar la arteria mamaria evitando su diseccion y clampaje supone un reto para la proteccion miocardica debido al lavado de la cardioplejia. Presentamos nuestra experiencia en reintervenciones sin disecar ni clampar los injertos arteriales. Material y metodos Desde septiembre de 2000 hasta febrero de 2010 se realizaron 29 reintervenciones en 28 pacientes, (89,7% varones), edad media 73,17 ± 7,38 anos. Las causas de reoperacion fueron: progresion de valvulopatia 17 pacientes (58,6%), endocarditis 10 (34,4%), disfuncion protesica no estructural 2 (6,9%). La mediana del EuroS-CORE logistico fue 14,84 (4-77,25). La cirugia fue urgente en 7 pacientes. Se realizo sustitucion valvular aortica aislada en 18 y se asocio revascularizacion en 4, sustitucion/plastia mitral en 4, sustitucion de aorta en 2; sustitucion mitral aislada en 1. La proteccion miocardica se realizo con cardioplejia hematica con esmolol, K + y Mg + , administrandola siempre que no dificultaba el trabajo quirurgico (intervalos nunca > 20 min). Temperatura sistemica media 32,26 ± 3,23 °C. Resultados La mediana del tiempo de circulacion extracorporea (CEC) fue 153 (91-494) y de clampaje 103 (71-430) min. Presentaron infarto postoperatorio 1 paciente (3,4%) y sindrome de bajo gasto postoperatorio 2 pacientes (6,5%). La mediana de troponina I postoperatoria fue 7,03 ng/ml (1,84-109,5). La mortalidad hospitalaria fue 3 pacientes (10,3%) (cirugia urgente por endocarditis). Las causas de mortalidad fueron: dano neurologico irreversible (1 paciente), sepsis y bajo gasto (2 pacientes). La mediana de estancia hospitalaria fue 7 (1-33) dias. Conclusion En nuestra experiencia, sin clampar los injertos arteriales y con la estrategia descrita, la proteccion miocardica parece adecuada y la mortalidad hospitalaria aceptable.

The study aim was to determine the influence of valve size and left ventricular (LV) mass on long-term LV diastolic reserve in patients subjected to aortic valve replacement for stenosis.Seventy-four patients (33 women, 41 men; mean age 64 years) after aortic valve replacement with 40 pericardial bioprostheses and 34 bileaflet mechanical prostheses were studied. All valves were of nominal size 19, 21 or 23 mm. The patients were studied by Doppler echocardiography, at rest and during peak effort, between 12 and 47 months after valve replacement.All patients achieved significantly increased heart rate, blood pressure and cardiac output in response to effort. Effort also significantly modified transvalvular pressure drops and valve areas. The mean diastolic reserve was 29.3 ml, and mean stroke volume reserve 23.2 ml; in neither case were there any significant differences between valve types, or among valve sizes.At about one year after surgery, the diastolic reserve of patients subjected to aortic valve replacement on account of stenosis was considerable, and independent of valve size. Despite the persistence of LV hypertrophy after valve replacement, LV diastolic function during effort was similar to that of the normal heart.

High density lipoproteins are an heterogeneous population of particles. Two main subpopulations have been identified, one contains Apo A-I and Apo A-II and is denominated LpA-I:A-II and another one contains only Apo A-I and is denominated LpA-I.To measure the concentrations of these particles in patients with stable coronary artery disease.Serum lipids, A-I and B apolipoproteins, LpA-I, LpA-I:A-II and LpB particles were measured in 73 men aged 33 to 82 years with angiographically documented coronary artery disease (CAD) and 33 control subjects aged 39 to 76 years. LpA-I, LpA-I:A-II and LpB were measured by a noncompetitive enzyme linked immunoassay using previously characterized monoclonal antibodies against ApoA-I, ApoA-II and apoB.Patients with CAD had significantly higher mean levels of LDL cholesterol than the control group (p = 0.038). The mean concentration of LpA-I particles in patients with CAD was significantly lower (p = 0.031) than in control subjects, while the concentration of LpA-I:A-II particles was significantly higher (p = 0.016). The percentage of coronary stenosis correlated negatively with LpA-I and positively with LpA-I:A-II. The best relative risk (RR) indicator in these patients was LDL-cholesterol. The relative risk increases 2.5 fold when LpA-I falls below the cut-off level. Likewise, the relative risk increases 3-fold when LpA-I:A-II raises over the cut-off level.Our findings indicate that the quantification of LpA-I and LpA-I:A-II particles might allow a more accurate evaluation of the CAD risk than HDL cholesterol. LpA-I might represent the antiatherogenic fraction of HDL.