Efficiently handling constraints in mixed-integer nonlinear programming problems using gradient-based repair differential evolution.

Mixed integer nonlinear programming (MINLP) addresses optimization problems that involve continuous and discrete/integer decision variables, as well as nonlinear functions. These problems often exhibit multiple discontinuous feasible parts due to the presence of integer variables. Discontinuous feasible parts can be analyzed as subproblems, some of which may be highly constrained. This significantly impacts the performance of evolutionary algorithms (EAs), whose operators are generally insensitive to constraints, leading to the generation of numerous infeasible solutions. In this article, a variant of the differential evolution algorithm (DE) with a gradient-based repair method for MINLP problems (G-DEmi) is proposed. The aim of the repair method is to fix promising infeasible solutions in different subproblems using the gradient information of the constraint set. Extensive experiments were conducted to evaluate the performance of G-DEmi on a set of MINLP benchmark problems and a real-world case. The results demonstrated that G-DEmi outperformed several state-of-the-art algorithms. Notably, G-DEmi did not require novel improvement strategies in the variation operators to promote diversity; instead, an effective exploration within each subproblem is under consideration. Furthermore, the gradient-based repair method was successfully extended to other DE variants, emphasizing its capacity in a more general context.

Neutrophil to lymphocyte ratio and systemic immune-inflammatory index as markers of response to autologous hematopoietic stem cell transplantation in persons with multiple sclerosis.

INTRODUCTION: Biomarkers that help to evaluate the immune system and could be useful in multiple sclerosis (MS) are the neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and systemic immune-inflammatory index (SII). The objective of this work is to evaluate the significance of the SII index, PLR, and NLR before and after transplantation in individuals with MS who underwent autologous hematopoietic stem cell transplant (aHSCT) at a single institution. METHODS: Patients with MS who received an aHSCT between 2017 and 2022 were included in the study. NLR, PLR, and SII index were calculated prior to the transplant and 100 days after, and evaluation of the expanded disability status scale (EDSS) was done before the transplant and 12 months after. The cohort was divided into two groups: aHSCT responders (R) and nonresponders (NR). RESULTS: Fifty-eight individuals were examined: 37 patients in the responders group R group and 21 in NR group. There was no statistically significant difference in the SII, NLR, and PLR prior to the transplant, however at 100 days post-HSCT, NLR in the R group was 1.8 versus 3.1 in the NR group (p = 0.003), PLR was 194 versus 295, respectively (p = 0.024), meanwhile SII index was 489.5 versus 729.3 (p < 0.001). CONCLUSION: High NLR and SII index values after the aHSCT were associated with a worsening in the EDSS score. However, since this is the first ever study that compared NLR and SII index with the aHSCT response in persons with MS, further studies must be performed to corroborate this information.

The consequences of delayed diagnosis and treatment in persons with multiple sclerosis given autologous hematopoietic stem cell transplantation.

OBJECTIVES: We have analyzed the association of delayed both diagnosis and treatment of persons with MS with the long-term results of patients given autologous hematopoietic stem cell transplantation (aHSCT). METHODS: Patients with MS referred to the HSCT-Mexico program were included in the study; in 103, detailed pre- and post-transplant evolution could be recorded. Two groups of patients were analyzed according to the time of evolution between the onset of symptoms and the definite diagnosis of MS: more than 8 months (delayed diagnosis, DD), or less than 8 months (non-delayed diagnosis, NDD). The progression of MS was assessed by changes in the expanded disability status scale (EDSS). RESULTS: The time elapsed between the onset of symptoms and the correct diagnosis was lower for the NDD group (1.55 vs. 35.87 months, p<0.05). Both groups of patients showed a similar EDSS score at diagnosis (1.5 vs. 1.5); however, the EDSS at the time of the transplant was higher in the DD group (4.5 vs. 3.0, p=0.3) and the response of the EDSS score to the transplant was significantly better for the NDD group, the last EDSS scores being 2.5 vs. 4.25 (p=0.03). Both groups of patients responded to aHSCT by diminishing the EDSS, but the response was significantly better in the NDD group. CONCLUSIONS: These data indicate that both the pre-transplant progression of the disease and the response to aHSCT were significantly worse in the DD group. An early diagnosis and an early aHSCT intervention are critical for a good prognosis, in terms of lowering and stabilizing the motor disability in MS patients given autografts.

Second Autologous Hematopoietic Stem Cell Transplantation in Multiple Sclerosis: A Single-Center Prospective Experience.

Immunosuppressive therapy is useful in persons with multiple sclerosis (MS), and autologous hematopoietic stem cell transplantation (aHSCT) is the most effective immunosuppressive treatment in this setting. Information on the usefulness of a second aHSCT in patients with MS is scarce. In a group of 1225 individuals with MS prospectively managed with aHSCT, we analyzed the salient features of 4 patients who received 2 consecutive transplants. After a moderate initial response to the first aHSCT, the patients were transplanted again after deterioration of their neurologic status; the second transplant was well tolerated and, in all instances, was completed on an outpatient basis and with no associated undesired toxicity. The autograft protocol is registered in ClinicalTrials.gov, identifier NCT02674217. After the second graft, the expanded disability status scale score stabilized in 2 patients; in 1, the post-transplant period was too short to assess the response, and in another, the development of associated Parkinson's disease precluded the assessment of the outcome. In conclusion, a second aHSCT in persons with MS is feasible, safe, and may lead to a positive response in some cases.

Cholesterol Exacerbates the Pathophysiology of Non-Alcoholic Steatohepatitis by Upregulating Hypoxia-Inducible Factor 1 and Modulating Microcirculatory Dysfunction.

Cholesterol is a pivotal lipotoxic molecule that contributes to the progression of Non-Alcoholic Steatohepatitis NASH). Additionally, microcirculatory changes are critical components of Non-Alcoholic Fatty Liver Disease (NAFLD) pathogenesis. This study aimed to investigate the role of cholesterol as an insult that modulates microcirculatory damage in NAFLD and the underlying mechanisms. The experimental model was established in male C57BL/6 mice fed a high-fat high-carbohydrate (HFHC) diet for 39 weeks. Between weeks 31-39, 2% cholesterol was added to the HFHC diet in a subgroup of mice. Leukocyte recruitment and hepatic stellate cells (HSC) activation in microcirculation were assessed using intravital microscopy. The hepatic microvascular blood flow (HMBF) was measured using laser speckle flowmetry. High cholesterol levels exacerbated hepatomegaly, hepatic steatosis, inflammation, fibrosis, and leukocyte recruitment compared to the HFHC group. In addition, cholesterol decreased the HMBF-cholesterol-induced activation of HSC and increased HIF1A expression in the liver. Furthermore, cholesterol promoted a pro-inflammatory cytokine profile with a Th1-type immune response (IFN-γ/IL-4). These findings suggest cholesterol exacerbates NAFLD progression through microcirculatory dysfunction and HIF1A upregulation through hypoxia and inflammation. This study highlights the importance of cholesterol-induced lipotoxicity, which causes microcirculatory dysfunction associated with NAFLD pathology, thus reinforcing the potential of lipotoxicity and microcirculation as therapeutic targets for NAFLD.

In persons with CIDP, auto-HSCT can be conducted fully on an outpatient basis and induces significant clinical responses: A prospective study in a single center.

BACKGROUND: Chronic inflammatory demyelinating polyneuropathy (CIDP) is one of the world's most common treatable neuropathy which usually responds to immunosuppressive treatment. Autologous hematopoietic stem cell transplantation (aHSCT) is an intense way of inducing immunosuppression. OBJECTIVE: We analyze the evolution of CIDP patients treated with aHSCT in our center. METHODS: Between 2018 and 2023, persons with CIDP were prospectively autografted employing the "Mexican method" to conduct grafts on an outpatient basis, employing cyclophosphamide 200 mg/Kg and rituximab 1000 mg. The protocol is registered in ClinicalTrials.gov identifier NCT02674217. RESULTS: In our center 21 autologous transplant cases were completed in 2018-2023. Seven patients provided data to assess the efficacy of the procedure. Positive responses (stabilization and/or improvement) were observed in all seven patients: Five reported improvements in the Inflammatory Neuropathy Cause and Treatment (INCAT) score and one reported stabilization. In the Inflammatory Rasch-Built Overall Disability Scale (I-RODS) score. Median INCAT score was 5 (range 1-9), whereas median I-RODS score was 24 (range 11-29). Five patients (71%) reported improvement in the INCAT score, one reported stabilization and one informed worsening; concerning the I-RODS score 5 (71%) informed improvement, whereas two reported stabilization. CONCLUSION: aHSCT conducted fully in an outpatient basis, employing the conditioning regimen of the "Mexican method" appears to be a feasible therapeutic option for persons with CIDP. Additional studies are needed to confirm these observations.

Can doses of post-transplantation cyclophosphamide in haploidentical stem cell allografts be reduced?

Objectives: Allogeneic hematopoietic stem cell transplantation (HSCT) remains the most important curative modality for several hematologic malignancies, but an HLA-matched sibling or unrelated donor is not always available, particularly for ethnic minorities and multiethnic families. We have shown that Haplo-HSCT can be conducted safely on an outpatient basis, using peripheral blood stem cells; this leading into substantial decreases in the costs. Methods: In this study twenty-one patients prospectively received the conventional dose of post-transplantation cyclophosphamide (PTCy): (50 mg/Kg on days 3 and 4), whereas 10 were given reduced doses of the drug (25 mg/Kg on days 3 and 4). Results: According to the statistical analysis, the two comparative groups (PTCy 50 mg/kg vs PTCy 25 mg/kg) had no significant difference in terms of age, sex, hematological recovery, and type of conditioning regimen. The median OS for the group PTCy 50 mg/kg is 5.7 months meanwhile for the group PTCy 25 mg/kg the median is 6.4 months. The median follow up for entire group is 4.5 months (IQR: 1.1-18.9 mo). Conclusion: These results could indicate that the Cy-dependent hematological toxicity can be reduced without compromising its effectivity. This preliminary observation may be considered as an idea to conduct prospective randomized studies to explore the possibility of significantly reducing the doses of PT-Cy in the setting of Haplo-HSCT.Trial registration: ClinicalTrials.gov identifier: NCT05780554.

Long-term results of autografting persons with multiple sclerosis are better in those not exposed to prior disease-modifying therapies.

INTRODUCTION: Multiple sclerosis (MS) is a disabling disease that affects young adults. Treatments for MS have increased exponentially in number, efficacy and risk. Autologous hematopoietic stem cell transplantation (aHSCT) can change the natural history of the disease. To analyze if aHSCT should be done early in the course of the disease or after failing of other therapies, we have studied the long-term results of aHSCT in a cohort of persons with MS who were given, or not, immunosuppressive drugs before the transplant. MATERIALS AND METHODS: Patients with MS referred to our center for aHSCT between June 2015 and January 2023 were prospectively entered in the study. All phenotypes of MS were included (relapsing remitting, primary progressive and secondary progressive). The follow up was assessed with the patient reported EDSS score in an online form; only patients followed by three or more years were included in the analysis. Patients were divided into two groups: Given or not disease modifying treatments (DMT) before the aHSCT. RESULTS: 1132 subjects were prospectively enrolled. 74 patients were followed for more than 36 months, and the subsequent analysis was done in this cohort. The response rate (RR = improvement + stabilization) at 12, 24 and 36 mo was 84%, 84% and 58% respectively for patients not receiving prior DMT and 72%, 90% and 67% for patients receiving DMT. In the whole group, the EDSS score dropped from a mean of 5.5 to 4.5 at 12 mo, to 5.0 at 24 mo and to 5.5 at 36 mo, after the aHSCT. The EDSS score was on average worsening in patients before the aHSCT, but the transplant stabilized the EDSS score at 3 years in patients with prior exposure to DMT, whereas in persons not given DMT, the transplant resulted in a significant decrease (p = .01) of the EDSS score. This indicates a positive response in all patients given aHSCT, but significantly better in those not exposed to DMT before the graft. CONCLUSION: The response to aHSCT was better for persons not exposed to immunosuppressive DMT before the transplant, thus suggesting that aHSCT should be done early in the course of the disease and probably before the treatment with DMT. Additional studies are needed to further analyze the impact of the use of DMT therapies before the aHSCT in MS, as well as the timing of the procedure.

Lipoabdominoplasty: What We Have Implemented and What We Have Modified over 26 Years.

Lipoabdominoplasty is one of the most commonly performed procedures in body-contouring surgery. We present a retrospective study of our 26 years of experience to improve the results and assure the greatest possible safety in lipoabdominoplasty. We include all of our female patients who underwent lipoabdominoplasty performed from July 1996 to June 2022, dividing the patients into two groups: group I underwent circumferential liposuction avoiding abdominal flap liposuction for the first 7 years, and group II underwent circumferential liposuction including abdominal flap liposuction for the subsequent 19 years, pointing out the differences in the processes, results, and complications of both groups. Over a period of 26 years, 973 female patients underwent lipoabdominoplasty: 310 in group I and 663 in group II. Ages were very similar; however, weight, BMI, amount of liposuction material, and weight of the abdominal flap removed were higher in group I. Twenty percent of patients in group I were obese compared to 7% in group II. The average amount of liposuction in group I was 4990 mL compared to 3373 mL in group II and 1120 g of abdominal flap in group I versus 676 g in group II. Minor and major complications were 11.6% and 1.2% in group I versus 9.2% and 0.6% in group II, respectively. In our more than 26 years of performing lipoabdominoplasty, we have maintained most of our initial procedures. These processes have allowed us to perform surgery safely and effectively with a low morbidity rate.

Aerobic Exercise Training Improves Microvascular Function and Oxidative Stress Parameters in Diet-Induced Type 2 Diabetic Mice.

Purpose: Type 2 diabetic (T2D) patients have liver and adipose tissue microcirculation disturbances associated with metabolic dysfunction and disease progression. However, the potential role of aerobic training on hepatic and white adipose tissue (WAT) microcirculation and the underlying mechanisms have not been elucidated to date. Therefore, we investigated the role of aerobic training on liver and WAT microcirculation and AGE-RAGE modulation in T2D mice. Methods: The control group (CTL) was fed standard chow, and T2D was induced by feeding male C57BL/6 a high-fat, high-carbohydrate diet for 24 weeks. In the following 12 weeks, mice underwent aerobic training (CTL EX and T2D EX groups), or were kept sedentary (CTL and T2D groups). We assessed metabolic parameters, biochemical markers, oxidative damage, the AGE-RAGE axis, hepatic steatosis, hepatic stellate cells activation (HSC) and liver and WAT microcirculation. Results: Hepatic microcirculation was improved in T2D EX mice which were associated with improvements in body, liver and fat mass, blood pressure, hepatic steatosis and fibrosis, and decreased HSC and AGE-RAGE activation. In contrast, improvement in WAT microcirculation, that is, decreased leukocyte recruitment and increased perfusion, was associated with increased catalase antioxidant activity. Conclusion: Physical training improves hepatic and adipose tissue microcirculatory dysfunction associated with T2D, likely due to downregulation of AGE-RAGE axis, decreased HSC activation and increased antioxidant activity.

Simvastatin Improves Microcirculatory Function in Nonalcoholic Fatty Liver Disease and Downregulates Oxidative and ALE-RAGE Stress.

Increased reactive oxidative stress, lipid peroxidation, inflammation, and fibrosis, which contribute to tissue damage and development and progression of nonalcoholic liver disease (NAFLD), play important roles in microcirculatory disorders. We investigated the effect of the modulatory properties of simvastatin (SV) on the liver and adipose tissue microcirculation as well as metabolic and oxidative stress parameters, including the advanced lipoxidation end product-receptors of advanced glycation end products (ALE-RAGE) pathway. SV was administered to an NAFLD model constructed using a high-fat-high-carbohydrate diet (HFHC). HFHC caused metabolic changes indicative of nonalcoholic steatohepatitis; treatment with SV protected the mice from developing NAFLD. SV prevented microcirculatory dysfunction in HFHC-fed mice, as evidenced by decreased leukocyte recruitment to hepatic and fat microcirculation, decreased hepatic stellate cell activation, and improved hepatic capillary network architecture and density. SV restored basal microvascular blood flow in the liver and adipose tissue and restored the endothelium-dependent vasodilatory response of adipose tissue to acetylcholine. SV treatment restored antioxidant enzyme activity and decreased lipid peroxidation, ALE-RAGE pathway activation, steatosis, fibrosis, and inflammatory parameters. Thus, SV may improve microcirculatory function in NAFLD by downregulating oxidative and ALE-RAGE stress and improving steatosis, fibrosis, and inflammatory parameters.

Disease presentation and surgical treatment of patients with foreign-body granulomas and ASIA syndrome: case series.

BACKGROUND: The result of illicit polymer injection is chronic inflammation with foreign-body granuloma (FBG) formation. Treatment can be divided into medical and surgical. Some patients develop severe complications with need surgical treatment. This study aims to describe patients who underwent surgical removal of the FBGs and autoimmune/inflammatory syndrome induced by adjuvants (ASIA); additionally, we evaluated the quality of life after surgery. METHODS: In this retrospective single-center study, the authors examined data of patients who underwent surgical removal of FBG caused by illicit polymer injection for cosmetic purposes and confirmed ASIA from 2015 to 2020 by three different surgical approaches. Descriptive summary statistics were reported on patient demographics, presenting symptoms and clinical examination features, treatment strategies, histopathology reports and quality of life. RESULTS: The cohort included 11 female patients with FBGs and ASIA. The most affected anatomical zones were the combination of gluteal region, thighs and legs (40%); and thighs with legs (20%). Main presentation was: skin hyperpigmentation (90.9%), skin induration (63.6%), chronic fatigue (63.6%), and ulcers (36.4%). Surgical modalities consisted of: ultrasonic-assisted liposuction in four patients (36.4%); open en bloc excision and primary closure in four patients (36.4%); and open en bloc excision and microsurgical reconstruction in three patients (27.2%). The postoperative quality of life visual analog scale score was 83.9. CONCLUSIONS: ASIA treatment represents a challenge for the plastic surgeon. Adequate surgical treatment emphasizing, when possible, the total or near-total resection of the FBG must be performed to improve ASIA evolution.

Pyridoxamine and Caloric Restriction Improve Metabolic and Microcirculatory Abnormalities in Rats with Non-Alcoholic Fatty Liver Disease.

INTRODUCTION: This study aims to examine the effect of a diet intervention and pyridoxamine (PM) supplementation on hepatic microcirculatory and metabolic dysfunction in nonalcoholic fatty liver disease (NAFLD). METHODS: NAFLD in Wistar rats was induced with a high-fat diet for 20 weeks (NAFLD 20 weeks), and control animals were fed with a standard diet. The NAFLD diet intervention group received the control diet between weeks 12 and 20 (NAFLD 12 weeks), while the NAFLD 12 weeks + PM group also received PM. Fasting blood glucose (FBG) levels, body weight (BW), visceral adipose tissue (VAT), and hepatic microvascular blood flow (HMBF) were evaluated at the end of the protocol. RESULTS: The NAFLD group exhibited a significant increase in BW and VAT, which was prevented by the diet intervention, irrespective of PM treatment. The FBG was elevated in the NAFLD group, and caloric restriction improved this parameter, although additional improvement was achieved by PM. The NAFLD group displayed a 31% decrease in HMBF, which was partially prevented by caloric restriction and completely prevented when PM was added. HMBF was negatively correlated to BW, FBG, and VAT content. CONCLUSION: PM supplementation in association with lifestyle modifications could be an effective intervention for metabolic and hepatic vascular complications.

Master Series Microsurgery for Residents: Results from a Comprehensive Survey of a Multitudinous Online Course during COVID-19 Pandemic.

BACKGROUND: Since COVID-19 emerged, it has significantly affected medical education. Surgical training has been blocked and the learning curve flattened. However, COVID-19 led to the outbreak of multitudinous online courses. Master series: microsurgery for residents (MSMR) has been the most extensive and accessible online nonfee course transmitted so far regarding reconstructive microsurgery. The primary aim of this study was to assess the impact of the MSMR in the surgical community as an international educational tool during pandemic confinement. METHODS: A retrospective, observational, analytic, and transversal study was designed. An 11-item survey was sent to all the 1,513 attendees who completed at least 60% of course attendance during 2 days. Descriptive and analytic statistics were performed. The impact was measured by considering answers to questions 6 to 9 and 11 (course usefulness, microsurgery interest increase, desire to pursue a microsurgical career, attendance to in-person conferences, and overall score, respectively). RESULTS: A total of 1,111 (73.4%) of eligible subjects were included. In total, 55.8% were plastic surgery residents. After the course, 98.9% would pursue a career in reconstructive microsurgery, and 45% would stop attending in-person conferences. The overall score of the event was 9.06 ± 0.9 (from 0 to 10) regardless of the current training status. CONCLUSION: The MSMR was a high impact course and has established a paradigm shift that will lead to an evolution in plastic surgery learning.

Inibição combinada do receptor AT1 e produtos finais de glicação avançada na nefropatia diabética / Combined inhibition of AT1 receptor and advanced glycation end products in diabetic nephropathy

O diabetes mellitus (DM) é um grande problema de saúde pública, que afeta cerca de 463 milhões de pessoas no mundo e pode alcançar 700 milhões de pessoas até 2045. A nefropatia é uma das complicações microvasculares do diabetes e a maior causa de insuficiência renal. Uma vez que a ativação do receptor AT1 pela angiotensina II causa vasoconstrição da artéria aferente, e que o acúmulo de produtos finais de glicação avançada (AGEs) causam glicotoxicidade intracelular de células mesangiais, podocitárias e tubulares, foi avaliado se o tratamento combinado de olmersatana (OLM) e piridoxamina (PYR) é capaz de melhorar a nefropatia diabética quando comparado aos tratamentos isolados. Para isto, o diabetes mellitus experimental foi induzido em 50 camundongos C57BL/6 pela administração de estreptozotocina (50 mg/kg/dia via intraperitoneal por 5 dias). Os animais foram divididos em cinco grupos: controle, diabéticos, diabéticos tratados com OLM (20 mg/Kg/dia), diabéticos tratados com PYR (400 mg/Kg/dia) e diabéticos tratados com OLM e PYR (20 mg/Kg/dia e 400 mg/Kg/dia, respectivamente) Os tratamento durou 16 semanas. Como resultado, os camundongos que receberam STZ desenvolveram hiperglicemia e doença renal, diminuição de peso, poliúria, polidipsia, polifagia, e albuminúria, além de aumento de frutosamina, ferro, uréia e fosfatase alcalina na urina, diminuição da atividade de catalase no rim e aumento de excreção dos AGEs na urina. Histologicamente, houve aumento de área glomerular e do espaço de BowmanO tratamento com OLM atenuou a albuminúria e atenuou o declínio da função renal, uma vez que o OLM melhorou a polidipsia, polifagia, poliúria, marcadores bioquímicos de disfunção renal e parâmetros histológicos, apesar de não apresentar ação sobre a fosfatase alcalina, uréia, ferro, frutosamina e ácido úrico. O tratamento isolado com PYR melhorou a maioria dos parâmetros alterados pela doença, entre eles a ingestão alimentar, ingestão hídrica, volume urinário, creatinina sérica, excreção de albumina na urina, ACR, AGEs no tecido renal e urina, ureia na urina e todos os parâmetros morfológicos analisados, contudo sem efeito sobre a fosfatase alcalina, ferro, frutosamina e ácido úrico. O tratamento combinado (PYR e OLM) melhorou a polifagia, polidipsia e poliúria comparado aos animais diabéticos sem tratamento, entretanto não houve diferença comparado a cada tratamento isolado. Os parâmetros histológicos e bioquímicos (creatinina no soro, albumina na urina, ACR e uréia) também apresentaram melhorara em relação aos animais diabéticos sem tratamento, mas não em relação aos animais em tratamento isolado. Tanto PYR quanto OLM não influenciaram a excreção de AGEs na urina. Esses dados nos levam a concluir que o tratamento combinado não ofereceu efeitos benéficos adicionais quando comparado aos tratamentos isolados, e que o tratamento que mais ofereceu benefícios foi o tratamento isolado com PYR nos parâmetros metabólicos, morfológicos e de função renal. (AU)

A Custom EOG-Based HMI Using Neural Network Modeling to Real-Time for the Trajectory Tracking of a Manipulator Robot.

Although different physiological signals, such as electrooculography (EOG) have been widely used in the control of assistance systems for people with disabilities, customizing the signal classification system remains a challenge. In most interfaces, the user must adapt to the classification parameters, although ideally the systems must adapt to the user parameters. Therefore, in this work the use of a multilayer neural network (MNN) to model the EOG signal as a mathematical function is presented, which is optimized using genetic algorithms, in order to obtain the maximum and minimum amplitude threshold of the EOG signal of each person to calibrate the designed interface. The problem of the variation of the voltage threshold of the physiological signals is addressed by means of an intelligent calibration performed every 3 min; if an assistance system is not calibrated, it loses functionality. Artificial intelligence techniques, such as machine learning and fuzzy logic are used for classification of the EOG signal, but they need calibration parameters that are obtained through databases generated through prior user training, depending on the effectiveness of the algorithm, the learning curve, and the response time of the system. In this work, by optimizing the parameters of the EOG signal, the classification is customized and the domain time of the system is reduced without the need for a database and the training time of the user is minimized, significantly reducing the time of the learning curve. The results are implemented in an HMI for the generation of points in a Cartesian space (X, Y, Z) in order to control a manipulator robot that follows a desired trajectory by means of the movement of the user's eyeball.

Variante de colgajo de rotación tipo Hamstring para reconstrucción de úlcera isquiática / Hamstring rotation fl ap variant for ischial ulcer reconstruction

Antecedentes. El colgajo Hamstring es una opción válida para la reconstrucción de úlceras isquiáticas. Las úlceras por presión representan un verdadero desafío para el cirujano plástico. Requieren un tratamiento especializado y multidisciplinario por su alta probabilidad de recidiva y las complicaciones en su manejo. Por lo general, ocurren por presión sostenida sobre la tuberosidad isquiática. Caso clínico. Se presenta el caso de un paciente parapléjico desde el nacimiento secundario a mielomeningocele con diagnóstico actual de úlcera isquiática. Se le realizaron durante 3 años múltiples intentos de cierre quirúrgico alternando medidas conservadoras, sin éxito. A la exploración física presenta una úlcera isquiática izquierda de 6x6 cm a la que se le realizó aseo y desbridación quirúrgica más cierre por medio de un colgajo Hamstring modificado. A los 7 días presentó dehiscencia de herida la cual se manejó de manera conservadora y cierre primario diferido a las 4 semanas. A 8 meses de posoperatorio el paciente se encuentra con buena evolución y con resultado estético y funcional aceptable, por otra parte, se encuentra sin recidiva, lo que ha permitido su reinserción laboral y un buen equilibrio físico-psico-emocional. Conclusión. El objetivo de este colgajo es brindar cobertura al área isquiática sin afectar estructuras adyacentes, lo cual requiere de un amplio conocimiento de la anatomía de la región femoral, así como de los colgados tanto locales como regionales que podemos utilizar para la reconstrucción. Actualmente este colgajo es una opción terapéutica efectiva para el tratamiento de úlceras isquiáticas refractarias en centros que cuentan con cirujanos plásticos no especializados en microcirugía.

Background. The Hamstring fl ap is an adequate option for ischial ulcers reconstruction. Pressure ulcers represent a real challenge for the plastic surgeon. They require specialized and multidisciplinary treatment due to their high recurrence probability and complications in their management. Regularly, pressure ulcers occur when sustained pressure is applied on the ischial tuberosity. Case report. We report a case of a 23-year-old paraplegic male with myelomeningocele complaining for an ischial ulcer. Multiple attempts to surgical closure were made during three years along with conservative management, without success. Physical examination revealed a 6x6 cm left ischial ulcer, which was managed with surgical debridement and closure with a modifi ed Hamstring fl ap. After 7 days, the patient presented wound dehiscence, which was managed conservatively and primary delayed closure after 4 weeks. 8 months postoperatively the patient has a good evolution and an acceptable functional and aesthetic result, without recurrence, which has allowed his reintegration into work and a good physical-psycho-emotional balance. Conclusion. The objective of this fl ap is to provide coverage to the ischial area without aff ecting adjacent structures, which requires a broad knowledge of the anatomy of the femoral region, as well as the local and regional fl aps that can be used for reconstruction. Nowadays this fl ap is an eff ective therapeutic option for the treatment of refractary ischial ulcers in plastis suergery centers without microsurgery.

Pyridoxamine improves metabolic and microcirculatory complications associated with nonalcoholic fatty liver disease.

OBJECTIVE: We investigated the protective effects of pyridoxamine against metabolic and microcirculatory complications in nonalcoholic fatty liver disease. METHODS: Nonalcoholic fatty liver disease was established by a high-fat diet administration over 28 weeks. Pyridoxamine was administered between weeks 20 and 28. The recruitment of leukocytes and the number of vitamin A-positive hepatic stellate cells were examined by in vivo microscopy. Laser speckle contrast imaging was used to evaluate microcirculatory hepatic perfusion. Thiobarbituric acid reactive substances measurement and RT-PCR were used for oxidative stress and inflammatory parameters. advanced glycation end products were evaluated by fluorescence spectroscopy. RESULTS: The increase in body, liver, and fat weights, together with steatosis and impairment in glucose metabolism observed in the nonalcoholic fatty liver disease group were attenuated by pyridoxamine treatment. Regarding the hepatic microcirculatory parameters, rats with high-fat diet-induced nonalcoholic fatty liver disease showed increased rolling and adhesion of leukocytes, increased hepatic stellate cells activation, and decreased tissue perfusion, which were reverted by pyridoxamine. Pyridoxamine protected against the increased hepatic lipid peroxidation observed in the nonalcoholic fatty liver disease group. Pyridoxamine treatment was associated with increased levels of tumor necrosis factor alpha (TNF-α) mRNA transcripts in the liver. CONCLUSION: Pyridoxamine modulates oxidative stress, advanced glycation end products, TNF-α transcripts levels, and metabolic disturbances, being a potential treatment for nonalcoholic fatty liver disease-associated microcirculatory and metabolic complications.