RESUMEN

BACKGROUND: The quick Sequential Sepsis-related Organ Failure Assessment (qSOFA) is a score that has been proposed to quickly identify patients at higher risk of death. OBJECTIVE: To describe the usefulness of the qSOFA score to predict in-hospital mortality in cancer patients. MATERIAL AND METHODS: Cross-sectional study carried out between January 2021 and December 2022. Hospital mortality was the dependent variable. The area under the ROC curve (AUC) was calculated to determine the discriminative ability of qSOFA to predict in-hospital mortality. RESULTS: A total of 587 cancer patients were included. A qSOFA score higher than 1 obtained a sensitivity of 57.2%, specificity of 78.5%, a positive predictive value of 55.4% and negative predictive value of 79.7%. The AUC of qSOFA for predicting in-hospital mortality was 0.70. In-hospital mortality of patients with qSOFA scores of 2 and 3 points was 52.7 and 64.4%, respectively. In-hospital mortality was 31.9% (187/587). CONCLUSION: qSOFA showed acceptable discriminative ability for predicting in-hospital mortality in cancer patients.

ANTECEDENTES: El quick Sequential Sepsis-related Organ Failure Assessment (qSOFA) es una puntuación propuesta para identificar de forma rápida a pacientes con mayor probabilidad de morir. OBJETIVO: Describir la utilidad de la puntuación qSOFA para predecir mortalidad hospitalaria en pacientes con cáncer. MATERIAL Y MÉTODOS: Estudio transversal realizado entre enero de 2021 y diciembre de 2022. La mortalidad hospitalaria fue la variable dependiente. Se calculó el área bajo la curva ROC (ABC) para determinar la capacidad discriminativa de qSOFA para predecir mortalidad hospitalaria. RESULTADOS: Se incluyeron 587 pacientes con cáncer. La puntuación qSOFA < 1 obtuvo una sensibilidad de 57.2 %, una especificidad de 78.5 %, un valor predictivo positivo de 55.4 % y un valor predictivo negativo de 79.7 %. El ABC de qSOFA para predecir mortalidad hospitalaria fue de 0.70. La mortalidad hospitalaria de los pacientes con qSOFA de 2 y 3 puntos fue de 52.7 y 64.4 %, respectivamente. La mortalidad hospitalaria fue de 31.9 % (187/587). CONCLUSIÓN: qSOFA mostró capacidad discriminativa aceptable para predecir mortalidad hospitalaria en pacientes con cáncer.

Asunto(s)

RESUMEN

Resumen Antecedentes: El quick Sequential Sepsis-related Organ Failure Assessment (qSOFA) es una puntuación propuesta para identificar de forma rápida a pacientes con mayor probabilidad de morir. Objetivo: Describir la utilidad de la puntuación qSOFA para predecir mortalidad hospitalaria en pacientes con cáncer. Material y métodos: Estudio transversal realizado entre enero de 2021 y diciembre de 2022. La mortalidad hospitalaria fue la variable dependiente. Se calculó el área bajo la curva ROC (ABC) para determinar la capacidad discriminativa de qSOFA para predecir mortalidad hospitalaria. Resultados: Se incluyeron 587 pacientes con cáncer. La puntuación qSOFA < 1 obtuvo una sensibilidad de 57.2 %, una especificidad de 78.5 %, un valor predictivo positivo de 55.4 % y un valor predictivo negativo de 79.7 %. El ABC de qSOFA para predecir mortalidad hospitalaria fue de 0.70. La mortalidad hospitalaria de los pacientes con qSOFA de 2 y 3 puntos fue de 52.7 y 64.4 %, respectivamente. La mortalidad hospitalaria fue de 31.9 % (187/587). Conclusión: qSOFA mostró capacidad discriminativa aceptable para predecir mortalidad hospitalaria en pacientes con cáncer.

Abstract Background: The quick Sequential Sepsis-related Organ Failure Assessment (qSOFA) is a score that has been proposed to quickly identify patients at higher risk of death. Objective: To describe the usefulness of the qSOFA score to predict in-hospital mortality in cancer patients. Material and methods: Cross-sectional study carried out between January 2021 and December 2022. Hospital mortality was the dependent variable. The area under the ROC curve (AUC) was calculated to determine the discriminative ability of qSOFA to predict in-hospital mortality. Results: A total of 587 cancer patients were included. A qSOFA score higher than 1 obtained a sensitivity of 57.2 %, specificity of 78.5 %, a positive predictive value of 55.4 % and negative predictive value of 79.7 %. The AUC of qSOFA for predicting in-hospital mortality was 0.70. In-hospital mortality of patients with qSOFA scores of 2 and 3 points was 52.7 and 64.4 %, respectively. In-hospital mortality was 31.9 % (187/587). Conclusions: qSOFA showed acceptable discriminative ability for predicting in-hospital mortality in cancer patients.

RESUMEN

Breast cancer remains the most frequently diagnosed cancer in women worldwide. Tumors that express hormone receptors account for 75% of all cases. Understanding alternative signaling cascades is important for finding new therapeutic targets for hormone receptor-positive breast cancer patients. JAK-STAT signaling is commonly activated in hormone receptor-positive breast tumors, inducing inflammation, proliferation, migration, and treatment resistance in cancer cells. In hormone receptor-positive breast cancer, the JAK-STAT cascade is stimulated by hormones and cytokines, such as prolactin and IL-6. In normal cells, JAK-STAT is inhibited by the action of the adaptor protein, LNK. However, the role of LNK in breast tumors is not fully understood. This review compiles published reports on the expression and activation of the JAK-STAT pathway by IL-6 and prolactin and potential inhibition of the cascade by LNK in hormone receptor-positive breast cancer. Additionally, it includes analyses of available datasets to determine the level of expression of LNK and various members of the JAK-STAT family for the purpose of establishing associations between expression and clinical outcomes. Together, experimental evidence and in silico studies provide a better understanding of the potential implications of the JAK-STAT-LNK loop in hormone receptor-positive breast cancer progression.

Asunto(s)

RESUMEN

RESUMEN Objetivo: Determinar el nivel de actividad física en un grupo de estudiantes universitarios por medio de un método indirecto. Materiales y métodos: Estudio con enfoque cuantitativo y alcance descriptivo, contó con una muestra representativa no probabilística de 304 sujetos, de los cuales 162 (53,2 %) eran mujeres y 142 (46,7 %) hombres; el instrumento empleado fue el cuestionario GPAQ Global Physical Activity Questionnaire, valorando con ello los MET en las categorías desplazamiento, trabajo, tiempo libre y conducta sedentaria. Resultados: Sobre los niveles AF a nivel general, el 62,5 % de los estudiantes evaluados presentó un nivel alto, un 12,2 % moderado y un 25,3 % bajo. Referente al comportamiento sedentario, el promedio general de los valorados en dicha variable fue de 6 horas diarias. En la distribución por género, los hombres presentaron un mayor nivel de AF con relación a las mujeres (p<0,05). Pero estas últimas, a su vez, tuvieron un mayor tiempo de AF sedentaria que los hombres (p<0,05). Conclusiones: Se encontró una relación asociada entre el género y los niveles de AF, siendo esta superior en el caso de los hombres; por su parte, los planes de estudio a nivel universitario deben fomentar e incluir la AF dentro de la formación integral, realizando mayor énfasis en las estudiantes del género femenino.

ABSTRACT Objective: To determine the level of physical activity in a group of university students by means of an indirect method. Materials and methods: A study with a quantitative approach and descriptive scope had a non-probabilistic representative sample of 304 subjects, of whom 162 (53.2 %) were women and 142 (46.7 %) men; the instrument used was the GPAQ Global Physical Activity Questionnaire, thereby assessing the METS in the categories: commuting, work and free time, as well as time spent in sedentary behavior. Results: On the FA levels at a general level, 62.5 % of the students evaluated presented a high level, 12.2 % moderate and 25.3 % low. Regarding sedentary behavior, the general average of those valued in said variable was 6 hours a day. In the distribution by gender, men presented a higher level of PA in relation to women (p<0.05). But the latter, in turn, had a longer sedentary PA time than the men (p<0.05). Conclusions: An associated relationship was found between gender and PA levels, this being higher in the case of men; on the other hand, the study plans at the university level should promote and include PA within comprehensive training, placing greater emphasis on female students.

RESUMEN

The adaptive filtering theory has been extensively developed, and most of the proposed algorithms work under the assumption of Euclidean space. However, in many applications, the data to be processed comes from a non-linear manifold. In this article, we propose an alternative adaptive filter that works on a manifold, thus generalizing the filtering task to non-Euclidean spaces. To this end, we generalized the least-mean-squared algorithm to work on a manifold using an exponential map. Our experiments showed that the proposed method outperforms other state-of-the-art algorithms in several filtering tasks.

RESUMEN

Cuffless blood pressure measurement enables unobtrusive and continuous monitoring that can be integrated with wearable devices to extend healthcare to non-hospital settings. Most of the current research has focused on the estimation of blood pressure based on pulse transit time or pulse arrival time using ECG or peripheral cardiac pulse signals as proximal time references. This study proposed the use of a phonocardiogram (PCG) and ballistocardiogram (BCG), two signals detected noninvasively, to estimate systolic blood pressure (SBP). For this, the PCG and the BCG were simultaneously measured in 21 volunteers in the rest, activity, and post-activity conditions. Different features were considered based on the relationships between these signals. The intervals between S1 and S2 of the PCG and the I, J, and K waves of the BCG were statistically analyzed. The IJ and JK slopes were also estimated as additional features to train the machine-learning algorithm. The intervals S1-J, S1-K, S1-I, J-S2, and I-S2 were negatively correlated with changes in SBP (p-val < 0.01). The features were used as explanatory variables for a regressor based on the Random Forest. It was possible to estimate the systolic blood pressure with a mean error of 3.3 mmHg with a standard deviation of ± 5 mmHg. Therefore, we foresee that this proposal has potential applications for wearable devices that use low-cost embedded systems.

Asunto(s)

RESUMEN

BACKGROUND: Urticaria is one of the most common causes of emergency room visits. It is defined as an acute inflammatory dermatosis, characterized by localized degranulation of mast cells, with consequent dermal microvascular and formation of edematous and pruritic plaques called hives. Urticaria affects the skin and tissues of the superficial mucosa. Sometimes it is accompanied by angioedema, which is characterized by deeper edema of the dermis and subcutaneous cellular tissue known as the urticarial-angioedema syndrome. About 15%-25% of the general population has suffered at least one type of urticaria at some point during their lifetime and hyperpermeability estimated at 7.6%-16% and has experienced acute urticaria that is usually self-limited and spontaneously resolves without requiring medical attention. CASE SUMMARY: We present the case of a young male patient who was referred to our department with a clinical picture of 4 mo of pruritus associated with hives of variable sizes, irregular borders, with interlesional confluence, that were non-painful, without involvement of the palms and soles of the feet but with a tendency to progression in a generalized manner. He had multiple emergency room visits and poor response to antihistamines and systemic corticosteroids. Imaging studies demonstrated nodules in the lower lingula segment, at the level of the greater fissure and in the anterior contour of the left anterior basal segment associated with parahiliar adenopathies in the absence of findings suggestive of infectious or autoimmune etiology. Segmental lobectomy was performed by thoracoscopy with resection of a lung nodule in the lingula and biopsy of the para-aortic mediastinal ganglion. The histopathological report showed the presence of poorly differentiated invasive adenocarcinoma with a solid morphological and acinar pattern with immunohistochemical description of lung tissue that expresses strong positive and diffuse reaction for thyroid transcription factor 1 (TTF-1) with negativity to P40 for a histopathological diagnosis of malignant epithelial neoplasia with expression of infiltrating adenocarcinoma. Spontaneous chronic urticaria is considered possibly secondary to lung adenocarcinoma. CONCLUSION: Chronic spontaneous urticaria is considered a paraneoplastic dermatosis with a controversial association in the literature. In the presented case, a young patient presented with chronic refractory urticaria and after an exhaustive clinical work-up was found to have a diagnosis of poorly differentiated lung adenocarcinoma with high expression of TTF-1. According to the Curth criteria, the urticaria presented by the patient is related to the oncological diagnosis. In addition, the high expression of TTF-1 documented in this case could be acting as an autoantigen that would cause chronic spontaneous urticaria. Further research evaluating a causal relationship between the TFF-1 protein and urticaria in lung cancer is needed.

RESUMEN

Triple-negative breast cancer (TNBC) is associated with a poor prognosis and the absence of targeted therapy. c-Kit, a receptor tyrosine kinase (RTK), is considered a molecular target for anticancer drugs. Tyrosine kinase inhibitors (TKIs) recognizing c-Kit are used for the treatment of c-Kit-expressing tumors. However, the expression, function, and therapeutic potential of c-Kit have been little explored in TNBC. Here, we studied the expression and effects of c-Kit in TNBC through in vitro and in silico analysis, and evaluated the response to TKIs targeting c-Kit. Analysis of TNBC cells showed the expression of functional c-Kit at the cell membrane. The stimulation of c-Kit with its ligand induced the activation of STAT3, Akt, and ERK1/2, increasing cell migration, but had no effect on cell proliferation or response to Doxorubicin. Analysis of public datasets showed that the expression of c-Kit in tumors was not associated with patient survival. Finally, TNBC cells were susceptible to TKIs, in particular the effect of Nilotinib was stronger than Doxorubicin in all cell lines. In conclusion, TNBC cells express functional c-Kit, which is a targetable molecule, and show a strong response to Nilotinib that may be considered a candidate drug for the treatment of TNBC.

Asunto(s)

RESUMEN

Resumen Introducción: las infecciones causadas por Enterococcus resistente a Vancomicina (EVR) presentan mayor mortalidad en pacientes críticos, asociado a un aumento gradual en este patrón de resistencia, especialmente en el continente americano, por lo cual la adecuada terapia antimicrobiana empírica es fundamental para mejorar los desenlaces. Objetivo: determinar los factores de riesgo asociados al desarrollo de infección por EVR en pacientes sépticos en la Unidad de Cuidados Intensivos (UCI) del Hospital San José en Bogotá, Colombia. Métodos: Estudio descriptivo de casos y controles en pacientes sépticos ingresados a la UCI durante 2016 y 2017. Los casos se definieron como pacientes con infección por EVR y los controles los pacientes con infección por otro germen. Resultados: se incluyeron 32 pacientes con aislamiento de EVR y 96 controles. Los factores de riesgo asociados a infección por EVR fueron: nutrición parenteral (OR 15,7 IC 4,2-71,4), lavado peritoneal (OR 8,9 IC 3,2-24,8), cultivo polimicrobiano (OR 19,9 IC 6,0-83,4). La mortalidad fue 56,2% en casos y 33,3% en controles. Conclusiones: Los factores de riesgo hallados con mayor frecuencia fueron: múltiples lavados peritoneales, nutrición parenteral y cultivos polimicrobianos. Encontramos una correlación significativa en el uso de antibiótico empírico adecuado y la reducción en la mortalidad.

Summary Introduction: infections caused by Vancomycin-resistant Enterococcus (VRE) have higher mortality in critically ill patients, associated with increase in this pattern of resistance, especially in the Americas, which is why adequate empirical antimicrobial therapy is essential to improve outcomes Objective: to determine the risk factors associated with the development of infection by VRE in septic patients in the Intensive Care Unit (ICU) of San José Hospital in Bogotá, Colombia. Methods: Case-control study in septic patients admitted to the ICU during 2016 and 2017. The cases were defined as patients with VRE infection and the controls were patients with infection by another germ. Results: 32 patients with EVR isolation and 96 controls were included. The risk factors associated with infection by EVR were: parenteral nutrition (OR 15.7 IC 4.2-71.4), peritoneal lavage (OR 8.9 IC 3.2-24.8), polymicrobial culture (OR 19,9 IC 6.0-83.4). Mortality was 56.2% in cases and 33.3% in controls. Conclusions: The risk factors found most frequently were: multiple peritoneal lavage, parenteral nutrition and polymicrobial cultures. We found a significant correlation in the use of adequate empirical antibiotic and the reduction in mortality

Asunto(s)

RESUMEN

The bacterial biofilm formation index (BFI) is measured by a microtiter plate assay, and it is typically performed at 72 hr. However, the dynamics of biopolymer formation change during this incubation period. The aims of this study were to follow the biofilm formation dynamics of Vibrio strains isolated from samples of seafood and food contact surfaces (FCS) and to propose a new BFI classification criterion. Samples from seafood (136) and FCS (14) were collected from retail markets in Queretaro, Mexico. The presence of Vibrio spp. was determined, the strains were isolated, and the six major pathogenic species (V. cholerae, V. alginolyticus, V. fluvialis, V. parahaemolyticus, V. vulnificus, V. mimicus) were identified by PCR. The BFI of the isolates was determined by the microtiter plate method. Fifty-one strains were isolated and identified as V. alginolytivcus (25), V. vulnificus (12), V. cholerae (7), V. parahaemolyticus (6), and V. mimicus (1). A quantitative classification criterion of biofilm formation was proposed based on the following factors: BFI dynamics (no formation, continuous increase, and increase followed by decrease), time of maximum BFI (early: 24 hr; late: 48 to 72 hr), and degree of BFI (none, weak, moderate, and strong). A numerical value was assigned to each factor to correlate the resulting BFI profile with a risk level. Thirteen BFI profiles were observed, having risk level values from 0 to 10. Vibrio alginolyticus, V. cholerae, and V. vulnificus showed the highest BFI profile diversities, which included the riskiest profiles. The proposed BFI criterion describes the dynamics of bacterial biopolymer formation and associates them with the possible risk implications. PRACTICAL APPLICATION: In food processing environments, the presence of bacterial biofilms that could include foodborne pathogens might favor cross-contamination due to direct contact or biofilm dispersal into food products. The new quantitative classification criterion for biofilm formation considers their production dynamics over time, the biofilm quantity, and the level of biofilm dispersal. These characteristics are represented by a numerical value that reflects the level of risk associated with the presence of a biofilm-producing strain on a food contact surface.

Asunto(s)

RESUMEN

Catechol 1,2 dioxygenases (C12DOs) have been studied for its ability to cleavage the benzene ring of catechol, the main intermediate in the degradation of aromatic compounds derived from aerobic degradation of hydrocarbons. Here we report the genome sequence of the marine bacterium Pseudomonas stutzeri GOM2, isolated from the southwestern Gulf of Mexico, and the biochemical characterization of its C12DO (PsC12DO). The catA gene, encoding PsC12DO of 312 amino acid residues, was cloned and expressed in Escherichia coli. Many C12DOs have been described as dimeric enzymes including those present in Pseudomonas species. The purified PsC12DO enzyme was found as an active trimer, with a molecular mass of 107 kDa. Increasing NaCl concentration in the enzyme reaction gradually reduced activity; in high salt concentrations (0.7 M NaCl) quaternary structural analysis determined that the enzyme changes to a dimeric arrangement and causes a 51% decrease in specific activity on catechol substrate. In comparison with other C12DOs, our enzyme showed a broad range of action for PsC12DO in solutions with pH values ranging from neutral to alkaline (70%). The enzyme is still active after incubation at 50°C for 30 min and in low temperatures to long term storage after 6 weeks at 4°C (61%). EDTA or Ca2+ inhibitors cause no drastic changes on residual activity; nevertheless, the activity of the enzyme was affected by metal ions Fe3+, Zn2+ and was completely inhibited by Hg2+. Under optimal conditions the k cat and K m values were 16.13 s-1 and 13.2 µM, respectively. To our knowledge, this is the first report describing the characterization of a marine C12DOs from P. stutzeri isolated from the Gulf of Mexico that is active in a trimeric state. We consider that our enzyme has important features to be used in environments in presence of EDTA, metals and salinity conditions.

RESUMEN

RESUMEN La situación de violencia en Colombia ha producido dinámicas que escapan al control del Estado y dificultan la construcción de la agenda pública de las instituciones estatales, ya que estas poseen limitaciones para describir el entorno social y político que influye en el territorio. Para suplir estas limitaciones, es pertinente generar redes semánticas que describan información sobre las comunidades víctimas del conflicto armado. Lo anterior permitirá generar un insumo que las instituciones y autoridades locales puedan emplear para reconocer pilares en la formación de políticas públicas coherentes a las necesidades de cada comunidad. En el presente artículo, se expone el proceso para la generación semiautomática de una red semántica a partir del tratamiento de datos textuales. Para tal fin, se han empleado herramientas de minería de textos y técnicas de análisis multivariado. La red semántica generada es una primera aproximación para la descripción de las características del caso de estudio de la comunidad de Arauca durante los años 2013-2018.

ABSTRACT The situation of violence in Colombia has produced dynamics that are beyond the control of the State and make it difficult for state institutions to build the public agenda. These institutions have limitations to describe the social and political environment that influence the territory To overcome these limitations, it is pertinent to generate semantic networks that describe information about communities victims of the armed conflict and, thus, generate an input that local institutions and authorities can use to recognize pillars in the formation of public policies consistent with the needs of each community. In this document is presented the process for the semi-automatic generation of a semantic network from the processing of textual data, using text mining tools and multivariate analysis techniques. The semantic network generated is a first approximation for the description of the characteristics of the Arauca community during the years 2013-2018, which was selected as a case study.

RESUMO A situação de violência na Colômbia tem produzido dinâmicas que estão além do controle do Estado e dificultam a construção de uma agenda pública por parte das instituições estatais, já que estas têm limitações na descrição do ambiente social e político que influencia o território. Para superar essas limitações, é pertinente gerar redes semânticas que descrevam as informações sobre as comunidades vítimas do conflito armado. Isto permitirá gerar um input que as instituições e autoridades locais possam utilizar para reconhecer pilares na formação de políticas públicas que sejam consistentes com as necessidades de cada comunidade. Neste artigo, é apresentado o processo para a geração semiautomática de uma rede semântica baseada no processamento de dados textuais. Para isso, foram utilizadas ferramentas de mineração de texto e técnicas de análise multivariada. A rede semântica gerada é uma primeira abordagem para descrever as características do estudo de caso da comunidade Arauca durante os anos 2013-2018.

RESUMEN

Revisión clínica, científica, teórica y documental teniendo como objetivo principal realizar una revisión sobre la porfiria aguda, su enfoque, diagnóstico y tratamiento. Se utilizó una metodología descriptiva, cualitativa y teórica que permitió la revisión bibliográfica de los estudios relacionados con la porfiria aguda, trastorno congénito poco frecuente que causa alteraciones en las enzimas de la biosíntesis del grupo hem. La importancia de esta patología radica en que se confunde con otras enfermedades debido al cuadro clínico complejo difícil de identificar, lo que ocasiona un diagnóstico tardío que puede comprometer la vida del paciente y por ello se conoce como enfermedad silenciosa. Como conclusión se recomienda mayor atención a los factores precipitantes de los ataques agudos por la elevada morbimortalidad, así como hacer un diagnóstico rápido y oportuno por medios cualitativos y cuantitativos solicitando PBG (porfobilinógeno) y ALA (ácido delta aminolevulínico).

This was a clinical, scientific, theoretical and documental review aimed to conduct a revision on the approach, diagnosis and treatment of acute porphyria. A descriptive, quantitative and theoretical methodology was used, allowing a bibliographic review of the studies on acute porphyria, an unusual congenital disorder characterized by the deficiency of specific enzymes involved in the heme group biosynthesis. This disease importance lies on being confused with other conditions due to its complex clinical manifestations leading to a delayed diagnosis which may become life-threatening thus it is known as a silent disease In conclusion, identifying the precipitating factors of acute attacks for its high morbidity and mortality, as well as achieving a rapid and timely diagnosis by using a quantitative or qualitative determination of PBG (porphobilinogen)) and ALA (delta-aminolevulinic acid) levels, deserve special attention.

Asunto(s)

RESUMEN

Machine learning, one of the core disciplines of artificial intelligence, is an approach whose main emphasis is analytical model building. In other words, machine learning enables an automaton to make its own decisions based on a previous training process. Machine learning has revolutionized every research sector, including health care, by providing precise and accurate decisions involving minimal human interventions through pattern recognition. This is emphasized in this research, which addresses the issue of "support for diabetic neuropathy (DN) recognition." DN is a disease that affects a large proportion of the global population. In this research, we have used gait biomarkers of subjects representing a particular sector of population located in southern Mexico to identify persons suffering from DN. To do this, we used a home-made body sensor network to capture raw data of the walking pattern of individuals with and without DN. The information was then processed using three sampling criteria and 23 assembled classifiers, in combination with a deep learning algorithm. The architecture of the best combination was chosen and reconfigured for better performance. The results revealed a highly acceptable classification with greater than 85% accuracy when using these combined approaches.

Asunto(s)

RESUMEN

The reconstruction of positron emission tomography data is a difficult task, particularly at low count rates because Poisson noise has a significant influence on the statistical uncertainty of positron emission tomography (PET) measurements. Prior information is frequently used to improve image quality. In this paper, we propose the use of a field of experts to model a priori structure and capture anatomical spatial dependencies of the PET images to address the problems of noise and low count data, which make the reconstruction of the image difficult. We reconstruct PET images by using a modified MXE algorithm, which minimizes a objective function with the cross-entropy as a fidelity term, while the field of expert model is incorporated as a regularizing term. Comparisons with the expectation maximization algorithm and a iterative method with a prior penalizing relative differences showed that the proposed method can lead to accurate estimation of the image, especially with acquisitions at low count rate.

RESUMEN

Positron emission tomography (PET) provides images of metabolic activity in the body, and it is used in the research, monitoring, and diagnosis of several diseases. However, the raw data produced by the scanner are severely corrupted by noise, causing a degraded quality in the reconstructed images. In this paper, we proposed a reconstruction algorithm to improve the image reconstruction process, addressing the problem from a variational geometric perspective. We proposed using the weighted Gaussian curvature (WGC) as a regularization term to better deal with noise and preserve the original geometry of the image, such as the lesion structure. In other contexts, the WGC term has been found to have excellent capabilities for preserving borders and structures of low gradient magnitude, such as ramp-like structures; at the same time, it effectively removes noise in the image. We presented several experiments aimed at evaluating contrast and lesion detectability in the reconstructed images. The results for simulated images and real data showed that our proposed algorithm effectively preserves lesions and removes noise.

Asunto(s)

RESUMEN

RESUMEN Objetivo Evaluar el efecto analgésico del extracto etanólico de las hojas de Pereskia lychnidiflora, la prospección de metabolitos secundarios y el análisis toxicológico. Materiales y métodos La actividad analgésica fue evaluada mediante la prueba del ácido acético y la formalina en ratones NIH a una concentración de 30, 50 y 100 mg/kg de peso corporal, utilizando como control Ibuprofeno a 200 mg/kg y agua destilada como blanco. La prospección de metabolitos secundarios se realizó por el método de cromatografía de capa fina y la toxicidad del extracto fue evaluada in vivo según la dosis máxima de 2000 mg/kg de peso corporal. Resultados La prospección fitoquímica determinó la presencia de alcaloides, taninos, triterpenos y esteroles como mayores constituyentes químicos. Se determinó que el extracto etanólico de Pereskia lychnidiflora posee una actividad analgésica similar al Ibuprofeno. No se observaron signos de toxicidad en los ratones de experimentación y se clasifica el extracto como no tóxico con una DL50 mayor de 2000 mg/kg. Conclusión El extracto etanólico de Pereskia lychnidiflora tiene un efecto analgésico antiinflamatorio que podría estar condicionado por la presencia de alcaloides, taninos y esteroles (terpenoides) presentes en esta especie vegetal y puede ser clasificado como no tóxico.

ABSTRACT Objective To evaluate the analgesic effect of the ethanolic extract of the leaves of Pereskia lychnidiflora, the prospection of secondary metabolites and the toxicologic analysis. Materials and Methods Analgesic activity was evaluated by testing acetic acid and formalin in NIH mice at a concentration of 30, 50 and 100 mg/kg body weight, using Ibuprofen control at 200 mg/kg and distilled water as the target. Secondary metabolites were prospected using the thin layer chromatography method and the toxicity of the extract was evaluated in vivo according to the maximum dose of 2,000 mg/kg body weight. Results Phytochemical prospecting determined the presence of alkaloids, tannins, triterpenes, and sterols as major chemical constituents. The ethanolic extract of Pereskia lychnidiflora was found to have an analgesic activity similar to ibuprofen. No signs of toxicity were observed in the experimental mice and the extract is classified as non-toxic with a DL50 greater than 2,000 mg/kg. Conclusions The ethanolic extract of Pereskia lychnidiflora has an anti- inflammatory analgesic effect that could be conditioned by the presence of alkaloids, tannins, and sterols (terpenoids) present in this species and can be classified as non-toxic.

Asunto(s)

RESUMEN

OBJECTIVE: To evaluate the analgesic effect of the ethanolic extract of the leaves of Pereskia lychnidiflora, the prospection of secondary metabolites and the toxicologic analysis. MATERIALS AND METHODS: Analgesic activity was evaluated by testing acetic acid and formalin in NIH mice at a concentration of 30, 50 and 100 mg/kg body weight, using Ibuprofen control at 200 mg/kg and distilled water as the target. Secondary metabolites were prospected using the thin layer chromatography method and the toxicity of the extract was evaluated in vivo according to the maximum dose of 2,000 mg/kg body weight. RESULTS: Phytochemical prospecting determined the presence of alkaloids, tannins, triterpenes, and sterols as major chemical constituents. The ethanolic extract of Pereskia lychnidiflora was found to have an analgesic activity similar to ibuprofen. No signs of toxicity were observed in the experimental mice and the extract is classified as non-toxic with a DL50 greater than 2,000 mg/kg. CONCLUSIONS: The ethanolic extract of Pereskia lychnidiflora has an anti- inflammatory analgesic effect that could be conditioned by the presence of alkaloids, tannins, and sterols (terpenoids) present in this species and can be classified as non-toxic.

OBJETIVO: Evaluar el efecto analgésico del extracto etanólico de las hojas de Pereskia lychnidiflora, la prospección de metabolitos secundarios y el análisis toxicológico. MATERIALES Y MÉTODOS: La actividad analgésica fue evaluada mediante la prueba del ácido acético y la formalina en ratones NIH a una concentración de 30, 50 y 100 mg/kg de peso corporal, utilizando como control Ibuprofeno a 200 mg/kg y agua destilada como blanco. La prospección de metabolitos secundarios se realizó por el método de cromatografía de capa fina y la toxicidad del extracto fue evaluada in vivo según la dosis máxima de 2000 mg/kg de peso corporal. RESULTADOS: La prospección fitoquímica determinó la presencia de alcaloides, taninos, triterpenos y esteroles como mayores constituyentes químicos. Se determinó que el extracto etanólico de Pereskia lychnidiflora posee una actividad analgésica similar al Ibuprofeno. No se observaron signos de toxicidad en los ratones de experimentación y se clasifica el extracto como no tóxico con una DL50 mayor de 2000 mg/kg. CONCLUSIÓN: El extracto etanólico de Pereskia lychnidiflora tiene un efecto analgésico antiinflamatorio que podría estar condicionado por la presencia de alcaloides, taninos y esteroles (terpenoides) presentes en esta especie vegetal y puede ser clasificado como no tóxico.

Asunto(s)

RESUMEN

Las fracturas mandibulares son las fracturas más comunes de los huesos faciales; las de cóndilo mandibular ocupan un lugar importante entreellas. Dentro de sus factores etiológicos destacan los accidentes detránsito, agresión por terceras personas, accidentes deportivos y laborales. Existe gran controversia en el manejo de dicha entidad en cuantoa la elección de un tratamiento conservador o quirúrgico; hay varios factores considerados como razones para llevar a cabo el tratamiento quirúrgico, como la pérdida de altura facial posterior, la posición delcóndilo fracturado o la posibilidad de que el paciente adquiera el material de osteosíntesis. En este artículo presentamos una alternativa en el manejo quirúrgico de fracturas condilares mediante técnica de Boyne, así como una breve descripción de la técnica quirúrgica que empleamos en el Servicio de Cirugía Oral y Maxilofacial del Centro Médico Licenciado Adolfo López Mateos, la cual nos ha proporcionado adecuados resultados estéticos y funcionales.

Mandibular fractures are the most common fractures of the facial bones, with mandibular condylar fractures occupying an important place among them. Some of their etiological factors are traffic accidents, aggressions by third persons, sports, and work accidents.There is great controversy in the management of this entity, regardingthe selection of a conservative or surgical treatment; several factorsare considered reasons to carry out the surgical treatment, such as the loss of posterior facial height, the position of the fractured condylar, aswell as the possibility of having the patient purchase the osteosynthesis material. In this article, we present an alternative in the surgical management of condylar fractures using Boyne’s technique, as wellas a brief description of the surgical technique we used in the Oraland Maxillofacial Surgery Service of the Medical Center «Licenciado Adolfo Lopez Mateos¼, which has provided us with Suitable aestheticand functional results.

Asunto(s)

RESUMEN

El carcinoma epidermoide cutáneo, es una neoplasia maligna la cual se origina a partir de los queratinocitos de la piel o mucosa, siendo considerado el segundo cáncer con más frecuencia en cabeza y cuello después del carcinoma basocelular. Su etiología es multifactorial, siendo el factor predisponente la exposición solar prolongada (radiación ultravioleta), la cual afecta directamente el ADN celular. Asimismo se ha asociado la infección por virus del papiloma humano, influyendo en el estado inmune del paciente. Es de suma importancia conocer factores de pronóstico como son: tamaño tumoral, profundidad, tipo histológico, invasión perineural, zonas de riesgo y zonas de drenaje, los cuales incrementaránel riesgo de recidiva y metástasis a distancia, impactando de manera importante en el pronóstico del paciente. El tratamiento del carcinoma epidermoide puede ser multimodal, desde cirugía, radioterapia y quimioterapia. En este artículo presentamos nuestra experienciaen el tratamiento del carcinoma epidermoide cutáneo de pacientefemenino de 64 años de edad, la cual es referida a nuestra consulta porla presencia de una lesión ulcerada en región frontal. Apegándonos a protocolos establecidos en la literatura internacional y nacional, se realiza resección quirúrgica más rotación de colgajos cutáneos para la reconstrucción del defecto residual, obteniendo resultados satisfactorios tanto funcionales como estéticos, los cuales impactan de forma directa en la calidad y pronóstico de vida de la paciente.

Cutaneous squamous cell carcinoma is a malignant tumor which originates from keratinocytes of the skin or mucosa, being consideredthe second most common cancer in the head and neck after basal cellcarcinoma. Its etiology is multifactorial, being the predisposing factorprolonged sun exposure (ultraviolet radiation), which directly affects thecell’s DNA, so it has been associated infection human papilloma virus,influencing the immune status of the patient. It is extremely important toknow prognostic factors such as: tumor size, depth, histological type,perineural invasion, risk areas and drainage areas, which will increasethe risk of recurrence and distant metastases, impacting significantlyon the forecast patient. Treatment of squamous cell carcinoma may bemultimodal, from surgery, radiotherapy and chemotherapy. We presentour experience in the treatment of squamous cell carcinoma skin of afemale 64 years old, which is referred to our clinic by the presenceof an ulcerated lesion in the frontal region, by adhering to protocolsestablished in international and national literature. Surgical resectionis performed more rotation skin flaps for reconstruction of the residualdefect, obtaining both functional and aesthetic satisfactory results,which directly impact the quality of life and prognosis of the patient.

Asunto(s)