Two-step hot isostatic pressing densification achieved non-porous fully-densified wood with enhanced physical and mechanical properties.

A new two-step densification method for wooden materials entitled hot isostatic pressing (HIP) is proposed. This method has the advantage over previous densification methods that can achieved almost the full densification of wood, reaching values up to 1.47 kg/m3, which exceeds any value ever reported for a hardwood species. Furthermore, it can preserve about 35% of the original volume, in comparison to other methods which typically can preserve only 20% of the volume. Although not tested in this investigation, in principle, the HIP method should be capable of densifying any shape of wood including circular and tubular cross sections because the main densification mechanism is based on gas pressure that is equally exerted in the entire surface, rather than localized mechanical compression, which can only be effective with rectangular cross sections. In the first stage of the two-step proposed method, the compressive strength of the anatomical wood structure is reduced by delignification, and, in the second, a full densification is achieved by hot isostatic pressing under argon atmosphere. Three tropical hardwood species with distinct anatomical characteristics and properties were used to test the method. The HIP-densified wood's microstructural, chemical, physical, and mechanical properties were assessed. Apart from the high densification values and volume preservation, the results indicate that proposed method was effective for all the tested species, showing homogenous density patterns, stable densification without noticeable shape recovery, and enhanced mechanical properties. Future research should test the HIP method in softwoods and consider the ring orientation in order to enhance the control of the densified geometry.

n-3 polyunsaturated fatty acids in the regulation of adipose tissue browning and thermogenesis in obesity: Potential relationship with gut microbiota.

BACKGROUND: Obesity is a worldwide public health problem characterized by fat tissue accumulation, favouring adipose tissue and metabolic alterations. Increasing energy expenditure (EE) through brown adipose tissue activation and white adipose tissue (WAT) browning has gained relevance as a therapeutic approach. Different bioactive compounds, such as n-3 polyunsaturated fatty acids (PUFA), have been shown to induce those thermogenic effects. This process is regulated by the gut microbiota as well. Nevertheless, obesity is characterized by gut microbiota dysbiosis, which can be restored by weight loss and n-3 PUFA intake, among other factors. Knowledge gap: However, the role of the gut microbiota on the n-3 PUFA effect in inducing thermogenesis in obesity has not been fully elucidated. OBJECTIVE: This review aims to elucidate the potential implications of this interrelation on WAT browning adiposw sittue (BAT), BAT activity, and EE regulation in obesity models.

Seroconversion and Abundance of IgG Antibodies against S1-RBD of SARS-CoV-2 and Neutralizing Activity in the Chilean Population.

COVID-19 is a pandemic caused by SARS-CoV-2. In Chile, half a million people have been infected and more than 16,000 have died from COVID-19. As part of the clinical trial NCT04384588, we quantified IgG against S1-RBD of SARS-CoV-2 (anti-RBD) in recovered people in Santiago and evaluated their suitability as COVID-19 convalescent plasma donors. ELISA and a luminescent SARS-CoV-2 pseudotype were used for IgG and neutralizing antibody quantification. 72.9% of the convalescent population (468 of 639) showed seroconversion (5-55 µg/mL anti-RBD IgG) and were suitable candidates for plasma donation. Analysis by gender, age, and days after symptom offset did not show significant differences. Neutralizing activity correlated with an increased concentration of anti-RBD IgG (p < 0.0001) and showed a high variability between donors. We confirmed that the majority of the Chilean patients have developed anti-SARS-CoV-2 antibodies. The quantification of anti-RBD IgG in convalescent plasma donors is necessary to increase the detection of neutralizing antibodies.

Reduction of high-fat diet-induced liver proinflammatory state by eicosapentaenoic acid plus hydroxytyrosol supplementation: involvement of resolvins RvE1/2 and RvD1/2.

High-fat diet (HFD)-fed mice show obesity with development of liver steatosis and a proinflammatory state without establishing an inflammatory reaction. The aim of this work was to assess the hypothesis that eicosapentaenoic acid (EPA) plus hydroxytyrosol (HT) supplementation prevents the inflammatory reaction through enhancement in the hepatic resolvin content in HFD-fed mice. Male C57BL/6J mice were fed an HFD or a control diet and supplemented with EPA (50 mg/kg/day) and HT (5 mg/kg/day) or their respective vehicles for 12 weeks. Measurements include liver levels of EPA, DHA and palmitate (gas chromatography), liver resolvins and triglyceride (TG) and serum aspartate transaminase (AST) (specific kits) and hepatic and serum inflammatory markers (quantitative polymerase chain reaction and enzyme-linked immunosorbent assay). Compared to CD, HFD induced body weight gain, liver steatosis and TG accumulation, with up-regulation of proinflammatory markers in the absence of histological inflammation or serum AST changes; these results were accompanied by higher hepatic levels of resolvins RvE1, RvE2, RvD1 and RvD2, with decreases in EPA and DHA contents. EPA+HT supplementation in HFD feeding synergistically reduced the steatosis score over individual treatments and increased the hepatic levels of EPA, DHA and resolvins, with attenuation of proinflammatory markers. Lack of progression of HFD-induced proinflammatory state into overt inflammation is associated with resolvin up-regulation, which is further increased by EPA+HT supplementation eliciting steatosis attenuation. These findings point to the importance of combined protocols in hepatoprotection due to the involvement of cross-talk mechanisms, which increase effectiveness and diminish dosages, avoiding undesirable effects.

Artropatía de Charcot / Charcot arthropathy

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Caracterización de pacientes portadores de marcapasos definitivo en el Hospital Regional de La Serena / Characterization of patients with definitive pacemaker in Hospital Regional de La Serena

INTRODUCCIÓN: La implantación de marcapasos definitivo se realiza en portadores de alteraciones en la generación del impulso cardíaco y/o con trastornos de la conducción. OBJETIVO: Caracterizar el perfil clínico-epidemiológico de los pacientes portadores de marcapasos definitivo en la Unidad de Cardiología del Hospital Regional de La Serena, en el período julio - septiembre de 2011. MATERIAL Y MÈTODO: Estudio descriptivo, de corte transversal. Se revisaron 103 fichas clínicas de pacientes marcapaso definitivo mediante muestreo aleatorio en la Unidad de Cardiología del Hospital Regional de La Serena. Se incluyeron pacientes mayores de 15 años con trastornos en generación del impulso y/o conducción irreversible. Se recopilaron y analizaron datos mediante Microsoft Excel 2007, identificándose características como sexo, edad, ruralidad, comorbilidades, manifestaciones clínicas, presencia o ausencia de Enfermedad de Chagas y cardiopatía específica. Se consideró significativo un p<0,05. RESULTADOS: Del total de 103 pacientes, 47,1 por ciento fueron mujeres. La edad promedio fue 74,5 +/- 12 años. La ruralidad fue de 49,51 por ciento Las manifestaciones clínicas más frecuentes fueron síncope (37,24 por ciento), disnea (32,34 por ciento) y mareos (24,46 por ciento). Del total de pacientes, 22 por ciento presentaron serología positiva para Tripanosoma Cruzi, 38 por ciento negativa y 40 por ciento sin serología. DISCUSIÓN: La principal causa de indicación de marcapasos definitivo fue el bloqueo auriculoventricular completo, correlacionándose con la literatura. No se encontró significancia estadística entre la severidad de la clínica y tipo de trastorno de la conducción. Se observó significancia estadística en la asociación entre ruralidad y serología para Tripanosoma Cruzi positiva y/o sin serología.

INTRODUCTION: The implant of definitive pacemaker is indicated in electrical impulse generation disorders and/or hearth electrical conduction abnormalities. OBJETIVE: Characterize clinically and epidemiologically the profile of patients with definitive pacemaker in the Cardiology Unit of the La Serena Regional Hospital, between July and September 2011. MATERIAL AND METHOD: Descriptive transversal cut study. 103 medical records of DPM diagnosed patients were analyzed by simple random sampling in the Cardiology Unit of the La Serena Regional Hospital. Patients with electrical impulse generation disorders and/or hearth electrical conduction abnormalities aged > 18 years old were included. Data collecting and analyzing were realized by Microsoft Excel 2007. The studied variables included: sex, age, rurality, disease, clinical symptoms, presence or absence of Chagas Disease and cardiopathies. Odss Ratio (OR) was calculated in significant differences situations in order to evaluate risk associated. A p< 0.05 was considered significant. RESULTS: Of the total of patients, 47.1 percent was women. The average age was 74.5 +/- 12 years. Rurality condition was 49.51 percent Most frecuent clinical symptoms were syncope (37.24 percent), dyspnoea (32.34 percent), dizziness (24.46 percent).Of 103 patients, 22 percent tested positive for Tripanosoma Cruzi, 38 percent tested negative and 40 percent without serology test. DISCCUSSION: The main definitive pacemaker indication was Complete Atrioventricular block, wich agree the literature. The association between clinical severity and hearth conduction abnormality type was not significant. We observed statistically significant differences between rurality condition and positive and/or without serologic test for Tripanosoma Cruzi.

Evidence for the participation of beta-hexosaminidase in human sperm-zona pellucida interaction in vitro.

Mammalian sperm-zona pellucida (ZP) interaction is mediated by sperm lectin-like proteins and ZP glycoproteins. We have previously reported the participation of binding sites for N-acetylglucosamine (GlcNAc) residues in human sperm function, including sperm interaction with the ZP. Additionally, previous results from our laboratory suggested that some of these events may be mediated by the glycosidase N-acetylglucosaminidase (beta-hexosaminidase, Hex, in mammals). In this study, we report the possible participation of Hex in human sperm-ZP interaction. Human recombinant Hex (hrHex) was obtained by expression in a stable transfected CHO cell line. When the recombinant enzyme was present during hemizona (HZ) assays, the number of sperm bound per HZ was significantly reduced. The same result was obtained when HZ were preincubated with hrHex. Additionally, the presence of a Hex-specific substrate during the HZ assay produced the same inhibitory effect. These results suggest the participation of a sperm Hex in the interaction with human ZP in vitro.

Strontium supports human sperm capacitation but not follicular fluid-induced acrosome reaction.

The ability of strontium (Sr(2+)) to replace calcium (Ca(2+)) in maintaining human sperm function has still not been completely characterized. In the present study, acrosome reaction (AR) inducibility in response to human follicular fluid (hFF) was compared in spermatozoa incubated in either Ca(2+)- or Sr(2+)-containing media. Other events related to sperm capacitation, such as protein tyrosine phosphorylation and hyperactivation as well as zona pellucida (ZP) recognition under both conditions, were also analyzed. Spermatozoa incubated overnight in the presence of Sr(2+) were unable to undergo the AR when exposed to hFF. Nevertheless, when spermatozoa were incubated under this condition and then transferred to medium with Ca(2+), sperm response to hFF was similar to that of cells incubated throughout in the presence of Ca(2+). The sperm protein tyrosine phosphorylation patterns and the percentages of sperm motility and hyperactivation were similar after incubation in Ca(2+)- or Sr(2+)-containing media. Under both conditions, the same binding capacity to homologous ZP was observed. Similar results were obtained when EGTA was added in order to chelate traces of Ca(2+) present in Sr(2+) medium. From these results, it can be concluded that Sr(2+) can replace Ca(2+) in supporting capacitation-related events and ZP binding, but not hFF-induced AR of human spermatozoa.

Transport in vitro fertilization and intracytoplasmic sperm injection: results of a collaborative trial.

OBJECTIVE: To determine whether the use of a central assisted reproduction laboratory, with gamete transport to the facility (transport assisted reproduction), would decrease oocyte quality or performance in IVF-ET and intracytoplasmic sperm injection (ICSI). DESIGN: Retrospective clinical study. SETTING: Public and private fertility clinics. PATIENT(S): A total of 467 couples underwent transport IVF, whereas 108 underwent transport ICSI. A group of 60 couples underwent conventional IVF during the same period. All methods and protocols used were similar among centers. Oocyte pick-up was performed by ultrasound-guided vaginal puncture. INTERVENTION(S): Oocytes were transported under controlled conditions, from the site of follicular aspiration to a central laboratory. MAIN OUTCOME MEASURE(S): The fertilization and cleavage rates and clinical pregnancies were compared among the study populations. RESULT(S): The differences between the fertilization and cleavage rates of ova and the rates of clinical pregnancies produced by transport and conventional methods were not statistically significant. CONCLUSION(S): Gamete transport to a central laboratory was not harmful for oocytes or for the outcome of assisted reproduction. Transport makes the use of IVF and ICSI available to physicians who are not affiliated with an assisted reproduction program, reduces costs, and increases acceptability of the procedures to patients.

Glycosidic residues involved in human sperm-zona pellucida binding in vitro.

Glycosidic residues of the mammalian zona pellucida (ZP) are known to be involved in sperm binding, suggesting the presence of complementary carbohydrate binding sites on spermatozoa. However, in previous studies, in which sperm suspensions were incubated with monosaccharides, no inhibitory effect was observed. Results of studies in which sperm were treated shortly after swim-up suggest that the use of non-capacitated cells may explain the apparently conflicting results. In the present report, we studied the effect of preincubation of capacitated spermatozoa with different monosaccharides on their ability to bind to ZP. After 5 h under capacitating conditions, spermatozoa were incubated in medium with or without a monosaccharide, resuspended in fresh medium and used for hemizona (HZ) binding assay. When ZH were incubated with spermatozoa treated with N-acetyl-D-glucosamine, D-mannose, D-fucose, L-fucose or D-galactose, a significant decrease in the number of spermatozoa bound was observed (level of inhibition: 62, 58, 82, 68 and 48% respectively) while treatment of spermatozoa with D-glucose produced no inhibition. Sugar treatment neither altered sperm motility nor the rate of acrosome reaction. These results suggest that N-acetylglucosamine, mannose, fucose and galactose residues are involved in human sperm-zona pellucida binding in vitro.

Taquicardia ventricular idiopática originada en el ventrículo izquierdo / Idiopathic ventricular tachicardia originated at left ventricle

Patients and methods: We report six patients (five male), aged 35 years old as a mean, with idiopathic left ventricular tachycardia that were subject to conventional electrophysiological studies with atrial and ventricular simulation programs and radiofrequency fulguration, between December 1993 and May 1996. Results: The mean lapse of disease was 24 months and five patients received antiarrytmic medications previously. All tachycardias had a morphology with an image of right bundle branch block. Radiofrequency fulguration was done after obtaining a satisfactory pace mapping of at least 11 of the 12 superficial EKG derivations. The procedure was successful in five patients and two had a relapse. One of the relapsed patients was successfully fulgurated again. Conclusions: Radiofrequency fulguration for idiopathic ventricular tachycardias is a safe and effective therapeutic procedure

[Is neonatal toxic erythema a risk factor in the development of allergy in childhood?]. / Es el eritema tóxico neonatal un factor de riesgo en el desarrollo de la alergia en la infancia?

OBJECTIVE: In relatively few cases have perinatal factors been included as risk factors for allergy development. Delivery has not been considered as a possible influential factor in allergy development. To identify risk factors in allergy development, we have included erythema toxicum neonatorum (ETN). PATIENTS AND METHODS: We have prospectively studied 356 newborns that were followed for a period of two years. Characteristics of the delivery, such as the pregnancy, instrumental delivery, circular cord, ETN, number of vesicles, day of presentation, season of birth, maternal and cord blood IgE levels and cord blood eosinophils and the development allergies during the two year follow-up period were included. RESULTS: ETN was seen in 25.3% of the children. The histopathology study of vesicles showed eosinophils. There was a significant difference between males and females (61.9% versus 38.1%, respectively). Cord blood IgE levels were not related to ETN, except in situations of allergy from 0.9 IU in cord blood or from 20 IU at six months of age (p < 0.05). CONCLUSIONS: ETN is related to delivery characteristics, instrumental, circulars, amniotic alteration or fall in arterial pH < 7.24. In 84.2% of allergy manifestations during the first two years of life, ETN or a low pH was seen at birth, with atopic dermatitis being those that displayed ETN (85.7%).

Connatal herpes zoster.

We describe a case of connatal herpes zoster present in a newborn girl whose mother had been exposed to varicella infection during the seventh month of pregnancy. A few minutes after delivery, the newborn was examined for an erythematous maculopapular rash with clear grouped vesicles involving the right L2-L4 dermatome. She was given varicella zoster immunoglobulin and oral and topical acyclovir, and all the skin lesions were completely healed eight days later. This report emphasizes one aspect of the relationship between maternal exposure to varicella zoster virus infection and the occurrence of connatal shingles, the benign course of the disease in this case, and the favorable response to acyclovir therapy in neonates.

Insuficiencia renal aguda en pacientes con y sin sepsis: pronóstico y evolución / Acute renal failure in septic and non septic patients: prognostic and evolution

The purpose of this prospective study was to determine whether the course and prognosis of acute renal failure (ARF) in patients with and without sepsis are different. 252 (8 percent) of 3086 consecutive patients admited to a medical surgical intensive care unit (ICU) developed ARE. One hundred forty-nine (59 percent) were septic and 103 (41 percent) were non-septic. No differences were founded between groups regarding the incidence of oliguria, hyperkalemia, hypercatabolism, gastrointestinal bleeding, duration of oliguria and renal deficit, severity of azotemia, dialysis requirements and duration of stay in the hospital. There were statistically significant differences between septic and non septic patients with respect to hyponatremia (67.8 vs 54.4 percent, p<0.04), respiratory failure (68 vs 54 percent, p<0.04), and thrombocytopenia (64 vs 48 percent, p<0.02). Mortality in septic patients was higher than in non-septics (56 vs 42.7 percent, p<0.009). Factors associated with increased mortality in ARF septic patients were respiratory failure, metabolic acidosis and oliguria while in the non-septics they were hepatic dysfunction, hyperkalemia, respiratory failure and infection acquired during the course of renal failure. We conclude that ARF developing in septic patients has a higher mortality than that of non-septic patients, whereas the incidence of hypercatabolism and oliguria was not different between both groups

A new predictive test for in-vitro fertilization based on the induction of sperm acrosome reaction by N-acetylglucosamine-neoglycoprotein.

Neoglycoproteins with N-acetylglucosamine residues (BSA-GlcNAc) induced specifically the acrosome reaction (AR) in human spermatozoa. Our objective was to investigate the relationship between this phenomenon and the invitro fertilization (IVF) rate. Sperm suspensions from IVF protocols were incubated with BSA-GlcNAc (t), using calcium ionophore (i) or medium alone (c) as positive or negative controls. When the normalized AR percentage ratio (STIM) (% ARt-%ARc):(%ARi-%ARc) was compared with fertilization rate in 31 couples from our IVF programme, a positive correlation was found (r = 0.46, P < 0.01). The fertilization rate in patients with STIM > or = 0.2 was higher than in non-responders (STIM < 0.2); 72 +/- 7% compared with 5 +/- 3%. The overall predictive value of this test for adequate fertilization rate (> 30%) was 87%, sensitivity 91% and specificity 78%. False positives were 9% and false negatives 22%. For successful fertilization rates (> 60%), the results were: overall predictive value, 84%; sensitivity 100%; specificity 64%. False positives were 23% and no false negatives were found. The results indicated that the induction of AR in human spermatozoa by GlcNAc-neoglycoproteins could be used to predict their fertilizing ability in vitro.