Dominant and sensitive control of oxidative flux by the ATP-ADP carrier in human skeletal muscle mitochondria: Effect of lysine acetylation.

The adenine nucleotide translocase (ANT) of the mitochondrial inner membrane exchanges ADP for ATP. Mitochondria were isolated from human vastus lateralis muscle (n = 9). Carboxyatractyloside titration of O2 consumption rate (Jo) at clamped [ADP] of 21 µM gave ANT abundance of 0.97 ±â€¯0.14 nmol ANT/mg and a flux control coefficient of 82% ±â€¯6%. Flux control fell to 1% ±â€¯1% at saturating (2 mM) [ADP]. The KmADP for Jo was 32.4 ±â€¯1.8 µM. In terms of the free (-3) ADP anion this KmADP was 12.0 ±â€¯0.7 µM. A novel luciferase-based assay for ATP production gave KmADP of 13.1 ±â€¯1.9 µM in the absence of ATP competition. The free anion KmADP in this case was 2.0 ±â€¯0.3 µM. Targeted proteomic analyses showed significant acetylation of ANT Lysine23 and that ANT1 was the most abundant isoform. Acetylation of Lysine23 correlated positively with KmADP, r = 0.74, P = 0.022. The findings underscore the central role played by ANT in the control of oxidative phosphorylation, particularly at the energy phosphate levels associated with low ATP demand. As predicted by molecular dynamic modeling, ANT Lysine23 acetylation decreased the apparent affinity of ADP for ANT binding.

[A prolonged capillary refill is predictor of low central venous oxygen saturation]. / El tiempo de llene capilar prolongado es predictor de una saturación venosa central de oxígeno disminuida.

INTRODUCTION: Educational programs in pediatric life support endorse a capillary refill time>2 s as an indicator of shock. In the emergency room, a barrier to the implementation of an early goal directed therapy, aiming at central venous oxygen saturation (ScvO2)≥70% is the insertion of central venous catheter (CVC). OBJECTIVE: To establish the predictive value of capillary refill time>2 s to detect ScvO2<70% in children admitted to Intensive Care Units. PATIENTS AND METHOD: Prospective study. We included 48 children admitted in the first 24 hours in ICU with superior vena cava CVC. Simultaneously, we measured ScvO2 and capillary refill time in the heel of upper extremity or toe. RESULTS: There were 75 paired measurements ScvO2 (75,9±8,4%) and capillary refill capillary (1,9±1,0 s). We found an inverse correlation between capillary refill time and ScvO2 (r-0,58). The ROC curve analysis revealed an excellent ability for the capillary fill time>2 s to predict ScvO2<70% (AUC 0,94) (95% CI 0,87-0,98). CONCLUSIONS: A prolonged capillary refill time>2 s, is a predictor of ScvO2<70% in children admitted to ICU, which supports the current recommendations. This finding may be relevant in emergency units where the use of CVC is limited and ScvO2 is not available.

Simplified culture techniques for growth and differentiation of murine and human pre-adipocytes for translational applications.

BACKGROUND: Adipose tissue has become a promising source of adult stem cells. Looking for optimal culture conditions, we evaluated the ability of L15, a free-gas exchange culture medium, to support cell proliferation and adipogenesis of murine 3T3-F442A and human normal (HNPA) and lipoma-derived (HLPA) pre-adipocytes. METHODS: 3T3-F442A, HNPA and HLPA cell proliferation were compared in short-term cultures and along multiple passages in Dulbecco's modified Eagle medium (DMEM) or DMEM-F12 under a 5% CO(2) atmosphere or L15 medium under a free-gas exchange atmosphere. Adipogenesis in these cells was evaluated by quantifying lipid accumulation and glycerol-3-phosphate dehydrogenase (GPDH) activity, and by assaying the expression of adipogenic markers by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: 3T3 pre-adipocytes grew at similar rates in serum-supplemented L15 or DMEM, but L15 induced higher colony-forming efficiency in these cells. HNPA and HLPA grew more actively in L15 than in DMEM-F12 for more than 10 successive passages and reached higher colony-forming efficiency in L15 medium. On the other hand, while high-glucose DMEM and L15 supplemented with glucose 1 g/L induced similar levels of 3T3 adipogenesis, L15 with no added glucose increased HNPA and HLPA adipogenesis with respect to DMEM-F12, as measured by lipid accumulation, GPDH activity and expression of adipogenic markers C/EBPalpha, GLUT-4, LPL and aP2. DISCUSSION: The free-gas exchange medium L15 supports cell proliferation and adipogenesis of murine 3T3 and normal and lipoma-derived human subcutaneous pre-adipocytes to a greater extent than DMEM or DMEM-F12. The routine use of L15 will optimize translational applications of adipose cells.

Methylprednisolone for the treatment of children with refractory epilepsy.

Epilepsy is a disease characterized by unprovoked epileptic seizures resulting from a bioelectrical brain dysfunction. Antiepileptic treatment controls 75% of all epileptic patients; the other 25% continue to have epileptic seizures in spite of a combination of multiple antiepileptic drugs. The purpose of this work was to evaluate the use of methylprednisolone in the treatment of children with refractory epilepsy. Fourteen children with refractory epilepsy at the Hospital de Especialidades No. 25 of the Instituto Mexicano del Seguro Social in Monterrey, Northeast Mexico were included. For five consecutively days, each patient received methylprednisolone by intravenous administration at a dosage of 15 mg/kg/day each 8 h, once a month for 3 months. The frequency of epileptic seizures and possible related side effects were evaluated every month during the three months before, during, and after administration of methylprednisolone. The frequency of epileptic seizures was reduced by more than 50% in 12/14 patients during methylprednisolone treatment. The median number of seizures before treatment with methylprednisolone was 8, 8, and 7; during the treatment: 1, 1, and 1; and after treatment: 2, 2, and 3 (p=0.000). We conclude that methylprednisolone reduces the frequency of epileptic seizures in children with refractory epilepsy.

Correction to: Comparison of healing of full-thickness skin wounds grafted with multidirectional or unidirectional autologous artificial dermis: differential delivery of healing biomarkers.

In the original article text presenting and discussing results shown in Fig. 6 omitted to mention that quantification of TGF-ß2 and TGF-ß3 was not included in Fig. 6a, c, e.

Ahead of the lanthanide contraction; pressure and ionic size in the synthesis of MSr2RECu2O8 (RE = Rare Earth, M = Ru, Cr, Ir): a Gaussian relation.

We have been working for sometime on the synthesis at high pressure (P < or = 12.5 Gpa) and high temperature (T < or = 1400 K) of new materials of the type MSr2RECu2O8 (RE = Rare Earth), which formally derive from YBCO (i.e., CuBa2YCu2O7) by replacing the [Cu-O4] squares in the basal plane of the structure by [M-O6] octahedra (M = Ru, Cr or Ir). The adequate formation of these cuprates, as majority phases, can only be performed in a particular and relatively narrow window of P and T, outside which they cannot be obtained pure or even obtained at all. These "optimum conditions" bear a remarkable Gaussian correlation with the rare earth ion size, the rare earth cation being at the center of the unit cell in the YBCO setting, and they do not follow the classic lanthanide contraction so often observed in the chemistry of those elements. Instead, interelectronic repulsion seems to play a major role in fixing the synthesis conditions. Moreover, the position of the Gaussian tip in the pressure-ionic radii space is also dependent on the transition metal that sits in the octahedron, in a way that seems related to the thermodynamic stability of their simpler oxides.

Increasing the structural complexity of chromium(IV) oxides by high-pressure and high-temperature reactions of CrO2.

This work presents an overview of a series of increasingly complex oxides synthesized from CrO 2, under high-pressure and high-temperature conditions, having Cr (4+) in octahedral coordination. Although the emphasis is on the structure and microstructure of the compounds as obtained from X-ray diffraction and transmission electron microscopy and diffraction, attention is also given to their interesting electronic and magnetic properties. The study is complemented with an electron energy loss spectroscopic analysis of the different phases. These are the cubic perovskite SrCrO 3, the orthorhombic perovskite CaCrO 3, the solid solution Sr 1-xCa xCrO 3, the Ruddlesden-Popper-type Sr 3Cr 2O 7, the family CrSr 2RECu 2O 8 (RE = rare earth), a compositionally modulated perovskite "PbCrO 3", and the misfit layer oxide SrO 2[CrO 2] 1.85.

Comparison of healing of full-thickness skin wounds grafted with multidirectional or unidirectional autologous artificial dermis: differential delivery of healing biomarkers.

Cytokines, chemokines, and growth and remodeling factors orchestrate wound healing when skin damage occurs. During early stages, when the wound is still open, detection and quantification of these compounds might provide biomarkers of skin wound healing, which could aid to complete the scenario provided by clinical follow-up data and histological and histomorphometric analyses. This work assessed and compared the healing of full-thickness skin wounds grafted with artificial dermis made with autologous skin fibroblasts and unidirectional or multidirectional type I collagen scaffolds to test this hypothesis. Biomarkers of healing were detected and quantified in the culture medium of artificial dermis and exudates from the grafted wounds. Clinical follow-up of animals and histological and histomorphometric analysis showed differences in graft integration, wound closure, and histological and histomorphometric parameters. Surface plasmon resonance quantification of 13 healing biomarkers indicated differential secretion of most of the quantified factors in culture medium by the multidirectional and unidirectional artificial dermis. Also, there were significant differences between the concentration of some of the factors analyzed in the exudates of wounds grafted with the evaluated artificial dermis. These findings suggest that differential delivery of healing biomarkers induced by the directionality of the scaffold used to produce the multidirectional and unidirectional dermis was sufficient to create two skin wound microenvironments that determined a different outcome of healing. Overall, data indicate that healing of wounds grafted with multidirectional autologous artificial dermis is better than that of the wounds grafted with the unidirectional one.

Immunogenicity in Protein and Peptide Based-Therapeutics: An Overview.

Currently it is well known that all biological drugs, including those with a fully human structure, are capable of inducing a host immune response known as immunogenicity [1]. The presence of ADAs can condition the drug´s level and action, thus modifying the therapeutic effect and even the safety profile by its mechanism of action - neutralizing or non-neutralizing - and / or an increase in its clearance. Immunogenicity is a dynamic factor to be taken into account in biological therapy, especially in long-term treatments, and as a relevant aspect in the assessment of secondary response loss [2]. With the above, not only the knowledge but also the management of the immunogenicity of the different biological treatments, represent a useful instrument for optimization of the strategies of use for each drug, and in the design of predictive models of response, which finally permits a significant improvement in the efficacy and safety profile, aiming to a personalization of the therapies, especially in patients with autoimmune diseases, genetic disorders and cancer [3]. This review summarizes the events of immunogenicity that produce the biological drug, the factor that influence to immunogenicity and the assessment of immunogenicity.

Diaphragmatic thickness ratio (inspiratory/expiratory) as a diagnostic method of diaphragmatic palsy associated with interescalene block. / La ratio de grosor diafragmático (inspiratorio/espiratorio) como método diagnóstico de parálisis diafragmática asociada al bloqueo interescálenico.

INTRODUCTION: Diaphragmatic paralysis is a side-effect associated with interscalene block. Thickness index of the diaphragm muscle (inspiratory thickness/expiratory thickness) obtained by ultrasound has recently been introduced in clinical practice for diagnosis of diaphragm muscle atrophy. Our objective was to evaluate this index for the diagnosis of acute phrenic paresis associated with interscalene block. PATIENTS AND METHODS: We designed an observational study in 22 patients scheduled for shoulder arthroscopy. Spirometry was performed (criteria of phrenic paresis was a decrease in FVC and FEV1 ≥20%). Ultrasound apposition zone was assessed in anterior axillary line and diaphragmatic displacement was evaluated on inspiration and expiration (number of intercostal spaces; phrenic paresis considered a reduction ≥25%) and thickness of the diaphragm muscle (a phrenic paresis was considered an index <1.2). These determinations were performed before and at 20min after interscalene block at C5-C6 with 20ml of 0.5% ropivacaine. RESULTS: Twenty-one patients (95%) presented phrenic nerve block according to one or more of the methods used. One patient did not show any symptoms or signs suggestive of phrenic paralysis and was excluded. All the patients presented phrenic paresis based on the diaphragmatic thickness index, with the pre-block index being 1.8±0.5 and post-block of 1.05±0.06 (P<0.001). Ninety percent of the patients (19) presented phrenic paresis according to spirometry and all the patients had a reduction in diaphragmatic movement after the block (from 1.9±0.5 intercostal spaces to 0.5±0.3; P<0.001). CONCLUSION: The index of inspiratory / expiratory diaphragmatic thickness at cut-off <1.2 seems to be useful in the diagnosis of phrenic paresis associated with interscalene block. This index does not require a baseline pre-assessment.

Reconstrucción lingual con colgajo libre radial: A propósito de un caso

Resumen El cáncer de lengua es una patología con una importante morbilidad e impacto en la calidad de vida del paciente, afectando la masticación, deglución, comunicación y gusto, por lo que requiere de un equipo multidisciplinario para establecer la rehabilitación adecuada. Se necesita realizar resecciones amplias para asegurar márgenes negativos, y si el cirujano considera que existe un volumen remanente insuficiente para obliterar la cavidad oral, la realización de un colgajo será necesario para mantener la función deglutoria. Se presenta el caso de un paciente de 76 años, masculino, con antecedentes de tabaquismo suspendido hace 23 años, que presenta una lesión ulcerada dolorosa en el borde derecho de la lengua móvil, la biopsia informa un carcinoma epidermoide, etapificado T2N0M0, por lo que se decide realizar hemiglosectomía derecha más disección cervical y reconstrucción con colgajo libre radial.

Abstract Tongue cancer is a pathology with significant morbidity and impact on the quality of life of the patients. It affects chewing, swallowing, communication, and taste. Therefore, a multidisciplinary team is required to establish adequate rehabilitation. Extensive resections are needed to ensure negative margins. If the surgeon considers that there is insufficient remaining volume to obliterate the oral cavity, flap surgery will be carried out to maintain the swallowing function. We present a case report of a 76-year-old male patient with a history of smoking cessation of 23 years. He presents a painful ulcerated lesion on the right edge of the mobile tongue. The biopsy reports an epidermoid carcinoma, staged T2N0M0 which led to perform a right hemiglosectomy, cervical dissection, and reconstruction with free radial forearm flap.

Prevalence of asthma, atopy and bronchial hyperresponsiveness and their interrelation in a semi-rural area of Chile.

OBJECTIVE: To assess the prevalence of asthma symptoms and their association with sensitisation to eight allergens and bronchial hyperresponsiveness (BHR) to methacholine. SETTING: A random sample of 1232 adults, aged 22 to 28 years, studied in a Chilean semi-rural area. DESIGN: A cross-sectional design for the purpose of this analysis. RESULTS: The prevalence of wheeze was 27.4% (95%CI 24.9-29.9) and waking with breathlessness 13.7% (95%CI 11.8-15.6), higher than the results of a multi-centre European study. Only 7.8% (95%CI 6.3-9.3) had a positive BHR (< or =8 mg/ml) and 26.3% (95%CI 23.8-28.8) were atopic. The Youden index of asthma symptoms in non-atopic subjects varied from 0.184 to 0.259 when using BHR as gold standard for asthma, and increased from 0.379 to 0.504 among those with positive atopy. Only 4.5% reported asthma, and the Youden index was slightly higher in comparison to the asthma symptom groups. CONCLUSION: The prevalence of asthma symptoms in young adults was high, but only a small proportion of these were sensitised or had a positive BHR. We believe that aetiological studies of asthma should analyse subjects with asthma symptoms separately from those with positive atopic status or positive BHR.

Control of fructose 2,6-bisphosphate levels in rat macrophages by glucose and phorbol ester.

The presence of fructose 2,6-bisphosphate (Fru 2,6-P2) in elicited peritoneal macrophages of rat was examined. These cells possess an active phosphofructokinase-2 which is diminished by citrate and only slightly inhibited by glycerol 3-phosphate. Phosphofructokinase-1 submaximal activity was increased 26-fold by the addition of 1 microM Fru 2,6-P2. Incubation of cells without glucose decreased the amount of Fru 2,6-P2 to zero, but further addition of 5 mM glucose increased the levels of the sugar ester 20-fold. In addition, the presence of phorbol ester potentiated the synthesis of Fru 2,6-P2. By contrast phenylisopropyladenosine or prostaglandin F2 alpha inhibited the production of Fru 2,6-P2.

Streptozotocin-induced diabetes increases fructose 2,6-biphosphate levels and glucose metabolism in thymus lymphocytes.

Acute effect of streptozotocin-induced diabetes on several parameters of glucose metabolism was investigated in thymus lymphocytes (thymocytes). The cells from diabetics rats accumulated in vitro about 2-fold more fructose 2,6-bisphosphate (Fru-2, 6-P2) in the presence of increasing glucose concentration than cells from normal rats. An increased production of lactate was also observed. Phosphofructokinase-1 (PFK-1) and phosphofructokinase-2 (PFK-2) activities were enhanced in cells from diabetic rats compared with those from normal rats. [U-14C]glucose incorporation into glycogen was also increased in cells from diabetic rats and the 14CO2 liberation was lesser than in cells from normal animals. From these data it may be concluded that the response of thymocytes to streptozotocin-induced diabetes is similar to that observed in other extrahepatic tissues.

Periareolar mammaplasty with silicone supporting lamina.

A mammaplasty technique through a periareolar incision and inferior pedicle trilobar flap with inclusion of a silicone supporting sheet was used in 485 patients between July of 1985 and December of 1989. The indications for the surgical treatment were ptosis, moderate to severe hypertrophy, or the association of both. The results were satisfactory in 458 patients (94.4 percent). The mean follow-up period was 22 months (range 6 to 50 months) in 427 patients without recurrences or functional alterations. No pathologic processes were observed as a result of use of the prosthesis. The silicone sheet did not interfere with manual, mammographic, or xeromammographic periodic examinations of the gland performed during the follow-up period. This technique has made it possible to mold the breast properly and to preserve its anatomic and functional unity, and in addition, it minimizes the scar and avoids recurrences.

Development of highly specific monoclonal antibodies for the diagnosis of Vibrio cholerae 01.

We report here the development of two monoclonal antibodies, termed 5G8 and 5C12, belonging to the IgM and IgG1 class, respectively, suitable for the identification of Vibrio cholerae 01 in clinical and environmental samples. The specificities of the monoclonals were evaluated by ELISA and indirect immunofluorescent microscopy of microorganisms normally present in stool samples and with two bacterial panels. One panel included 72 potentially antigenically related bacterial strains and the second panel included 20 pathogenic bacterial strains involved in diarrhea cases. The results of these extensive analyses indicate that monoclonal antibodies 5G8 and 5C12 are highly specific and suitable for the clinical diagnosis of Vibrio cholerae 01 in human stool samples by indirect immunofluorescent microscopy. Although the antigenic sites recognized by these antibodies were not identified in this study, the observation of Western blot patterns suggested that 5G8 and 5C12 monoclonal antibodies bind to LPS epitopes, a good structural marker for the detection of V. cholerae 01 because it is present in all bacterial cell walls.

[Diaphragmatic traumatic chronic hernia. Report of 3 cases]. / Hernia diafragmática traumática crónica. Presentación de tres casos.

Diaphragmatic traumatic chronic hernias are infrequent. Diagnostic can be difficult if don't exist suspicion and treatment is always by surgery. The aim of this paper is to present three cases and makes an actualisation in basis to our experience and the literature.

Puntos críticos en la evaluación y tratamiento de octogenarios con colecistolitiasis / Critical points in the evaluation and treatment of octogenarians with colecistolitiasis

Resumen Introducción: Existe una tendencia global al envejecimiento y con ello un aumento de patologías asociadas. En Chile la prevalencia de la colelitiasis o colecistolitiasis aumenta con la edad, siendo la cole-cistectomía una de las cirugías más frecuentes. Existen escasos estudios latinoamericanos referentes a la realidad de la población octogenaria expuesta a este problema. Objetivo: Estudiar la morbimortalidad posoperatoria en pacientes octogenarios operados de colecistectomía. Definir la precisión de distintas herramientas diagnósticas preoperatorias, estudiar variables operatorias y precisar costos hospitalarios. Materiales y Método: Estudio observacional retrospectivo de la ficha clínica electrónica del Hospital Clínico de la Universidad de Chile, entre enero de 2012 y mayo de 2017. Se incluyeron pacientes con edad igual o mayor a 80 años, en quienes se realizó una colecistectomía electiva o de urgencia por patología benigna. Resultados: Se incluyeron 145 pacientes, 51,7% fueron mujeres, el promedio de edad fue de 84,1 años y un 74,5% presentaba comorbilidades. El 62,1% de los casos ingresó por urgencia. 26,2% de toda la muestra presentó coledocolitiasis. La colecistectomía fue laparoscópica en 73,8% de la muestra global, la tasa de conversión fue de 14,5% en población de urgencia y 1,8% en población electiva (p = 0,009). La población operada totalmente por vía laparoscópica con coledocolitiasis fue resuelta en un 95,2% a través de Rendez-vous, con una tasa de éxito del 100%. La tasa de complicaciones fue de 17,9% siendo en su mayoría médicas, la mortalidad quirúrgica fue de 2,1%, siendo todos casos de urgencia. El costo promedio de atención en salud hospitalaria fue de $5.888.104 pesos chilenos (U$9.000). Conclusión: El paciente octogenario con colecistolitiasis representa un desafío quirúrgico, dado un mayor número de comorbilidades, un cuadro clínico más agresivo y una elevada tasa de coledocolitiasis. Es aconsejable valorar el abordaje mínimamente invasivo y realizar una colangiografía intraoperatoria de rutina.

Introduction: There is a global tendency to aging and associated pathologies. In Chile, the prevalence of cholecystolithiasis increases with age, cholecystectomy is one of the most frequent surgeries in the contry. There are few latinamerican studies regarding the reality of the elderly exposed to this problem. Objective: Study postoperative morbimortality in octogenarian patients undergoing cholecystectomy. Define the accuracy of different preoperative diagnostic tools, study operative variables and specify hospital costs. Materials and Method: Retrospective observational study of the Clinical Hospital of the University of Chile, between January 2012 and May 2017. Patients with age equal to or greater than 80 years were included, in whom an elective or emergency cholecystectomy was performed for benign pathology. Results: A total of 145 patients were included, 51.7% were women, the average age was 84.1 years, and 74.5% had comorbidities. The admission was throw the emergency department in 62.1% of the cases. Choledocholithiasis was diagnosed in 26.2% of the entire sample. Cholecystectomy was fully laparoscopic in 73.8% of the overall sample, the conversion rate was 14.5% in the emergency population and 1.8% in the elective population (p = 0.009). The population operated fully laparoscopically, that had choledocholithiasis, was resolved in 95.2% through Rendezvous technique, with a 100% clearance rate of common bile duct. The complication rate was 17.9%, most being medical. The surgical mortality was 2.1%, all cases operated from emergency. The average cost of hospital health care was $5,888,104.3 Chilean pesos (U$9.000). Conclusion: The octogenarian patient with cholecystolithiasis represents a surgical challenge, given a greater number of comorbidities, a more aggressive clinical setting and a high rate of choledocolithiasis. It is advisable to assess the minimally invasive approach and perform routine intraoperative cholangiography. In the postoperative period, the cardiopulmonary status and the infectious complications of the surgical site should be monitored closely.

[Therapeutic hypothermia after pediatric cardiac arrest]. / Hipotermia terapéutica en la parada cardiorrespiratoria pediátrica.

INTRODUCTION: Therapeutic hypothermia (TH) improves neurological outcome in adults after ventricular fibrillation cardiac arrest and in neonates with hypoxic ischemic encephalopathy. The effect of TH in children is under investigation. OBJECTIVES: To assess the feasibility, efficacy and safety of a pilot program of TH in pediatric cardiac arrest. MATERIAL AND METHODS: Prospective study in a pediatric intensive care unit. An external cooling method with a servo system was used on all patients according to an established protocol. Values expressed as median (IQ range). RESULTS: Six patients were included, of whom 5 had an out of hospital cardiac arrest. The mean age was 33 months (16-120) and Glasgow coma scale 6 (4-7). The T° prior to the induction of TH was 39.2° C (39.1-39.4). The median T° used was 34.0° C (33.5-34.8° C), which was reached in 4h. (3-7) after the start and maintained for 48h. (45-54). The rewarming was carried out over a period of 14h. (12-16). Hypokalemia was the most common adverse event found. Five patients survived to hospital discharge with a Glasgow Coma Scale of 13 (11-14). At 6 months follow up the Pediatric Cerebral Performance Category score was ≤ 2 in three patients. CONCLUSION: In this pilot study, the use of mild therapeutic hypothermia with a protocol that included rapid sequence induction with an external surface cooling technique was feasible, effective and safe in children with cardiac arrest.