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1.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1536321

RESUMO

Introducción: El artículo reflexiona sobre la naturaleza multidimensional y compleja de la ética y su relación con las ciencias médicas. Objetivo: Reflexionar sobre la atención a pacientes en estadio terminal desde el punto de vista de la ética médica para una atención médica integral en el primer nivel de atención. Métodos: estudio cualitativo; se emplearon análisis documental, sistematización, análisis y síntesis de publicaciones sobre la temática estudiada como métodos teóricos, para ello se valoran los criterios de autores y resultados que se expresan en artículos publicados. Se realizaron búsquedas, tanto en bases de datos estudiadas como en las plataformas de productos del Nacional Council for Biotechnology Information de la Nacional Library of Medicine of United States of America; y de Elsevier, esta última productora de Embase y Scopus, a través del motor de búsqueda Google Académico, en español e inglés, y sin límite de tiempo. Se emplearon los términos: ética médica, deontología médica, relación médico-paciente, paciente terminal y cuidados paliativos. Se excluyeron aquellos artículos que no habían sido revisados por pares o no mostraban el texto completo. Se revisó la información suministrada por cada fuente y se sintetizó. Conclusiones: En Cuba, la bioética avanza en la medida que lo permite la estrategia de Atención Primaria de Salud, con un Programa del Médico y Enfermera de la Familia resiliente y de valores humanos demostrados nacional e internacionalmente. Como reto se plantea estimular el debate entre saberes para generar cambios a favor de los pacientes, las familias, las comunidades y la sociedad(AU)


Introduction: The article reflects on the multidimensional and complex nature of ethics and its relationship to the medical sciences. Objective: To reflect on the care of terminally ill patients from the point of view of medical ethics for comprehensive medical care at the primary level of care. Methods: A qualitative study was carried out using documentary analysis, systematization, analysis and synthesis of publications on the subject studied as theoretical methods. For this purpose, the criteria of authors and results expressed in published articles were evaluated. Searches were carried out in Spanish and English through Google Scholar, and without time limit, both in the databases studied and in the product platforms of the National Council for Biotechnology Information of the National Library of Medicine of the United States of America and Elsevier. The terms: medical ethics, medical deontolog, physician-patient relationship, terminal patient and palliative care were used. Articles that were not peer-reviewed and those that did not show the full text were excluded. The information provided by each source was reviewed and synthesized. Conclusions: In Cuba, bioethics advances to the extent allowed by the Primary Health Care strategy, with a resilient Family Physician and Nurse Practitioner Program and human values demonstrated nationally and internationally. The challenge is to stimulate the debate between knowledge to generate changes in favor of patients, families, communities and society(AU)


Assuntos
Humanos , Masculino , Feminino , Cuidados Paliativos/métodos , Relações Médico-Paciente/ética , Assistência Terminal/métodos , Serviços de Saúde Comunitária , Ética Médica
2.
Biomedicines ; 10(8)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36009489

RESUMO

Currently, there are no reliable biomarkers for the diagnosis of pancreatic cancer (PaC). Glycoproteomic approaches that analyze the glycan determinants on specific glycoproteins have proven useful to develop more specific cancer biomarkers than the corresponding protein levels. In PaC, mesothelin (MSLN) is a neo-expressed glycoprotein. MSLN glycosylation has not been described and could be altered in PaC. In this work, we aimed to characterize MSLN glycans from PaC cells and serum samples to assess their potential usefulness as PaC biomarkers. First, we analyzed MSLN glycans from PaC cell lines and then we developed an enzyme-linked lectin assay to measure core fucosylated-MSLN (Cf-MSLN) glycoforms. MSLN glycans from PaC cells were analyzed by glycan sequencing and through Western blotting with lectins. All of the cell lines secreted MSLN, with its three N-glycosylation sites occupied by complex-type N-glycans, which were mainly α2,3-sialylated, core fucosylated and highly branched. The Cf-MSLN glycoforms were quantified on PaC serum samples, and compared with MSLN protein levels. The Cf-MSLN was significantly decreased in PaC patients compared to control sera, while no differences were detected by using MSLN protein levels. In conclusion, Cf-MSLN glycoforms were differently expressed in PaC, which opens the way to further investigate their usefulness as PaC biomarkers.

3.
Materials (Basel) ; 15(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35806662

RESUMO

In this study, a thick hollow axisymmetric functionally graded (FG) cylinder is investigated for steady-state elastic stresses using an iteration technique and the finite element method. Here, we have considered a functionally graded cylinder tailored with the material property, namely, Young's modulus, varying in an exponential form from the inner to outer radius of the cylinder. A mathematical formulation for stress analysis of functionally graded cylinder under internal and external pressure conditions is developed using constitutive relations for stress-strain, strain-displacement relations and the equation of equilibrium. The effect of the in-homogeneity parameter on radial displacement, radial and tangential stresses in a functionally graded cylinder made up of a High Carbon Steel (HCS) metal matrix, reinforced with Magnesium Oxide (MgO) ceramic is analyzed. The iterative method implemented is fast and converges to the solution which can be further improved by considering a higher number of iterations. This is depicted graphically by using radial displacement and stresses in a pressurized functionally graded cylinder obtained for the first two iterations. An iterative solution for non-FGM (or homogeneous material) is validated using the finite element method. The mechanical responses of the functionally graded cylinder obtained from the iterative method and the finite element method are then compared and found to be in good agreement. Results are presented in graphical and tabular form along with their interpretations.

4.
Healthcare (Basel) ; 10(5)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35628018

RESUMO

The evolution of the coronavirus (COVID-19) disease took a toll on the social, healthcare, economic, and psychological prosperity of human beings. In the past couple of months, many organizations, individuals, and governments have adopted Twitter to convey their sentiments on COVID-19, the lockdown, the pandemic, and hashtags. This paper aims to analyze the psychological reactions and discourse of Twitter users related to COVID-19. In this experiment, Latent Dirichlet Allocation (LDA) has been used for topic modeling. In addition, a Bidirectional Long Short-Term Memory (BiLSTM) model and various classification techniques such as random forest, support vector machine, logistic regression, naive Bayes, decision tree, logistic regression with stochastic gradient descent optimizer, and majority voting classifier have been adapted for analyzing the polarity of sentiment. The effectiveness of the aforesaid approaches along with LDA modeling has been tested, validated, and compared with several benchmark datasets and on a newly generated dataset for analysis. To achieve better results, a dual dataset approach has been incorporated to determine the frequency of positive and negative tweets and word clouds, which helps to identify the most effective model for analyzing the corpora. The experimental result shows that the BiLSTM approach outperforms the other approaches with an accuracy of 96.7%.

5.
Materials (Basel) ; 15(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35269034

RESUMO

Creep is an irreversible time-dependent deformation in which a material under constant mechanical stress and elevated temperature for a considerably prolonged period of time, starts to undergo permanent deformation. Creep deformation occurs in three stages namely, primary, secondary and tertiary. Out of these three stages, secondary or steady state creep is particularly an area of engineering interest as it has almost a constant creep rate. Creep deformation plays a significant role in understanding effective service life of an engineering component working under high temperature conditions as such components such as super-heater and re-heater tubes and headers in a boiler, jet engines operating at temperature as high as 1200 ∘C, usually experience a failure or rupture due to creep phenomenon. Design engineers keep a close attention on working stress conditions and elevated temperature under which an engineering component is expected to work as these conditions determine the onset of creep behavior in an engineering component. By recognizing the parameters of material response to creep behavior, engineers can analyse the useful service life and hazardous working conditions for an engineering components. Recognizing the creep phenomenon as high temperature design limitation, ASME Boiler and Pressure Vessel Code have provided guidelines on maximum allowable stresses for materials to be used in creep range. One of the criteria for determination of allowable stresses is 1% creep deformation of material in 100,000 h of service. Thus, the study of creep behavior in engineering components pertaining to high stress and temperature working conditions is very important as it affects the reliability and performance of the engineering components. The aim of our study is to understand the behavior of secondary creep deformation so that an advanced reinforced functionally graded material with better creep resistance, can be designed. In this paper, a secondary creep analysis of functionally graded (FG) thick-walled rotating cylinder under internal and external pressure is conducted. The novelty of the model intends to specify secondary creep stresses and strains by employing exponential, linear and quadratic volume reinforcement for SiCp ceramic in Al metal matrix in radial direction. This will help us to understand the effect of volume reinforcement in FG cylinder under internal/external pressure and rotating centrifugal body force by obtaining secondary creep stresses and strains. The response of the FG cylinder with isotropic material is analyzed and the solution for stress-strain rates in radial and tangential directions are obtained in closed form. Comparison of steady state creep stresses and strains under exponential, linear and quadratic volume reinforcement profiles are discussed and presented graphically.

6.
R Soc Open Sci ; 8(3): 201840, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33959344

RESUMO

Sustainability is a target that involves many socio-ecological questions, depends on opportunities and combines different initiatives. This can be especially difficult in regions with high biodiversity scores, mega cities, high level of human populations and an intense and long-standing land use. Here, we show how a mega trail, named Atlantic Forest Trail, within the Brazilian Atlantic Forest can join the protection of biodiversity and sustainable tourism through a 4270 km corridor connecting protected areas and crossing a variety of landscapes. Further, we show some initiatives of ongoing biodiversity monitoring, and an analysis of ecological restoration in private lands that can be applied in many regions to improve habitat connectivity for both biodiversity and human use.

7.
Biol Conserv ; 255: 108994, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33568834

RESUMO

This paper examines the effects of the COVID-19 pandemic on environmental protection and legislation in Brazil. We evaluate major legislative actions, environmental fines and deforestation since January 2019. We show that 57 legislative acts aimed at weakening environmental protection in Brazil during the current administration, almost half of which in the seven-month period of the pandemic in Brazil, with September 2020 as the month with the most legislative acts (n = 16). These acts either deregulated or weakened current environmental legislation, with a number of them aimed at dismantling the main federal institutions in charge of environmental protection. We also found a 72% reduction in environmental fines during the pandemic, despite an increase in Amazonian deforestation during this period. We conclude that the current administration is taking advantage of the COVID-19 pandemic to intensify a pattern of weakening environmental protection in Brazil. This has the potential to intensify ongoing loss of biodiversity, greenhouse gas emissions, and the likelihood of other zoonotic disease outbreaks, and inflict substantial harm to traditional and indigenous peoples. We highlight the key role of the scientific community, media and civil society, national and international levels, in order to reverse these harmful actions.

8.
J Proteomics ; 231: 104004, 2021 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-33038510

RESUMO

Late diagnosis of pancreatic ductal adenocarcinoma (PDA) is one of the reasons of its low 5-year survival rate and it is due to its unspecific symptoms during the first stages of the disease and the lack of reliable serological markers. Since PDA shows an altered glycan expression, here we have focused on finding novel potential biomarkers, namely glycoproteins that express the tumor associated carbohydrate structure sialyl-Lewis x (sLex), which is described in PDA. Through a glycoproteomic approach, we have analyzed target proteins containing sLex from PDA tissues by 2DE and immunodetection techniques, and have identified by mass spectrometry the protein MFAP4 as a carrier of sLex in PDA. MFAP4 showed a higher expression in PDA tissues compared with pancreatic control tissues. In addition, the colocalization of sLex over MFAP4 was found only in PDA and not in control pancreatic tissues. The analysis of MFAP4 expression in PDA cell lines and their secretome, in combination with immunohistochemistry of pancreatic tissues, revealed that MFAP4 was not produced by PDA cells, but it was found in the pancreatic extracellular matrix. The specificity of MFAP4 glycoform containing sLex in PDA tissues shows its relevance as a potential PDA biomarker. SIGNIFICANCE: Despite advances in the field of cancer research, pancreatic ductal adenocarcinoma (PDA) lacks of a specific and sensitive biomarker for its early detection, when curative resection is still possible before metastases arise. Thus, efforts to discover new PDA biomarkers represent the first line in the fight against the increase of its incidence reported in recent years. Glycan alterations on glycoconjugates, such as glycoproteins have emerged as a rich source for the identification of novel cancer markers. In the present work, we aimed to shed light on novel biomarkers based on altered glycosylation in PDA, in particular those glycoproteins of PDA tissues carrying the tumor carbohydrate antigen sialyl-Lewis x (sLex). Through a glycoproteomic approach, we have shown that the glycoprotein MFAP4 carries sLex in PDA tissues and not in control pancreatic tissues. MFAP4 is found in the extracellular matrix in PDA and although its role in cancer progression is unclear, its sLex glycoform could be a potential biomarker in pancreatic ductal adenocarcinoma.


Assuntos
Adenocarcinoma , Proteínas de Transporte , Proteínas da Matriz Extracelular , Glicoproteínas , Neoplasias Pancreáticas , Antígeno Sialil Lewis X , Adenocarcinoma/diagnóstico , Biomarcadores Tumorais , Glicoproteínas/metabolismo , Humanos , Microfibrilas/metabolismo , Neoplasias Pancreáticas/diagnóstico
9.
Educ. med. (Ed. impr.) ; 20(supl.2): 148-153, sept. 2019.
Artigo em Espanhol | IBECS | ID: ibc-193078

RESUMO

Históricamente dentro de la enseñanza médica y en la constitución de las estructuras organizacionales y la cultura médica se ha puesto poco énfasis en la promoción y la enseñanza de habilidades interpersonales, esenciales para que el personal clínico ofrezca un trato humanizado a sus pacientes y a sus equipos de trabajo. Así mismo, han sido muy pocos los esfuerzos por entender las consecuencias que tienen las presiones típicas de la formación médica en las condiciones de vida y salud mental de los estudiantes. Por esto, la presente revisión narrativa de la literatura tiene como objetivo identificar los tipos de currículos existentes y establecer sus implicaciones, en particular los currículos ocultos, en la aparición de factores de riesgo para la salud mental en estudiantes de Medicina. Esta reflexión sirve de referencia cuando se están planteando en Latinoamérica reformas curriculares que buscan transformar la enseñanza de la Medicina y dar un giro a la profesión médica


Historically, within medical education and in the constitution of organizational structures and medical culture, little emphasis has been placed on the promotion and teaching of inter-personal skills, which is essential to offer a humanised treatment of clinical staff with their patients and their co-workers. Likewise, there have been very few efforts to understand the consequences of the typical pressures of medical training on the living conditions and mental health of students. Therefore, the present narrative review of the literature aims to identify the existing types of curricula and establish their implications, in particular the hidden curricula, and in the appearance of risk factors for mental health in medical students. This reflection serves as a reference when curriculum reforms are being considered in Latin America that aim to transform the teaching of medicine and transform the medical profesión


Assuntos
Humanos , Promoção da Saúde/organização & administração , Saúde Mental , Estudantes de Medicina/psicologia , Currículo/normas , Papel Profissional/história , Educação Baseada em Competências/normas , Estudantes de Medicina/estatística & dados numéricos , Socialização , Educação/história , Educação/normas , Papel do Médico/história
10.
Cir Esp ; 95(5): 261-267, 2017 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28583725

RESUMO

INTRODUCTION: Compared to other surgical areas, laparoscopic liver resection (LLR) has not been widely implemented and currently less than 20% of hepatectomies are performed laparoscopically worldwide. The aim of our study was to evaluate the feasibility, and the ratio of implementation of LLR in our department. METHODS: We analyzed a prospectively maintained database of 749 liver resections performed during the last 10-year period in a single centre. RESULTS: A total of 150 (20%) consecutive pure LLR were performed between 2005 and 2015. In 87% of patients the indication was the presence ofprimary or metastatic liver malignancy. We performed 30 major hepatectomies (20%) and (80%) were minor resections, performed in all liver segments. Twelve patients were operated twice and 2 patients underwent a third LLR. The proportion of LLR increased from 12% in 2011 to 62% in the last year. Conversion rate was 9%. Overall morbidity rate was 36% but only one third were classified as severe. The 90-day mortality rate was 1%. Median hospital stay was 4 days and the rate of readmissions was 6%. CONCLUSIONS: The implementation of LLR has been fast with morbidity and mortality comparable to other published series. In the last 2 years more than half of the hepatectomies are performed laparoscopically in our centre.


Assuntos
Hepatectomia/métodos , Laparoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepatectomia/estatística & dados numéricos , Unidades Hospitalares , Humanos , Laparoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
11.
Cir. Esp. (Ed. impr.) ; 95(5): 261-267, mayo 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-163965

RESUMO

Introducción: En comparación con otras áreas quirúrgicas, la resección hepática laparoscópica (RHL) no se ha aplicado de forma generalizada y en la actualidad menos del 20% de las hepatectomías se realiza por vía laparoscópica en todo el mundo. El objetivo de nuestro estudio fue evaluar la aplicabilidad y la proporción de RHL en nuestro departamento. Métodos Los datos de morbimortalidad y supervivencia se extrajeron de una base de datos prospectiva con 749 resecciones hepáticas realizadas durante un período de 10 años en un solo centro. Resultados: Entre 2005 y 2015 se realizaron 150 RHL. En el 87% de los pacientes la indicación fue la presencia de tumores hepáticos primarios o metastásicos. Se realizaron 30 hepatectomías mayores (20%) y el 80% fueron resecciones menores, realizadas en todos los segmentos del hígado. Doce pacientes fueron operados 2veces y 2 pacientes tuvieron una tercera RHL. La proporción de RHL aumentó del 12% en 2011 al 62% en el último año. La tasa de conversión fue del 9%. En general, la tasa de morbilidad fue del 36%, pero solo 1/3 se clasificaron como graves. La tasa de mortalidad a los 90 días fue del 1%. La mediana de estancia fue de 4 días y la tasa de reingresos fue del 6%. Conclusiones: La aplicación de RHL ha sido rápida y progresiva, con resultados de morbimortalidad comparables a las de las series publicadas en la literatura. En los últimos 2 años más de la mitad de las hepatectomías se realiza por vía laparoscópica en nuestro centro (AU)


Introduction: Compared to other surgical areas, laparoscopic liver resection (LLR) has not been widely implemented and currently less than 20% of hepatectomies are performed laparoscopically worldwide. The aim of our study was to evaluate the feasibility, and the ratio of implementation of LLR in our department. Methods: We analyzed a prospectively maintained database of 749 liver resections performed during the last 10-year period in a single centre. Results: A total of 150 (20%) consecutive pure LLR were performed between 2005 and 2015. In 87% of patients the indication was the presence ofprimary or metastatic liver malignancy. We performed 30 major hepatectomies (20%) and (80%) were minor resections, performed in all liver segments. Twelve patients were operated twice and 2 patients underwent a third LLR. The proportion of LLR increased from 12% in 2011 to 62% in the last year. Conversion rate was 9%. Overall morbidity rate was 36% but only one third were classified as severe. The 90-day mortality rate was 1%. Median hospital stay was 4 days and the rate of readmissions was 6%. Conclusions: The implementation of LLR has been fast with morbidity and mortality comparable to other published series. In the last 2 years more than half of the hepatectomies are performed laparoscopically in our centre (AU)


Assuntos
Humanos , Hepatectomia/estatística & dados numéricos , Neoplasias Hepáticas/cirurgia , Laparoscopia/estatística & dados numéricos , Colangiocarcinoma/cirurgia , Indicadores de Morbimortalidade , Resultado do Tratamento , Complicações Pós-Operatórias
12.
Elife ; 62017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28362260

RESUMO

The connection between gene loss and the functional adaptation of retained proteins is still poorly understood. We apply phylogenomics and metabolic modeling to detect bacterial species that are evolving by gene loss, with the finding that Actinomycetaceae genomes from human cavities are undergoing sizable reductions, including loss of L-histidine and L-tryptophan biosynthesis. We observe that the dual-substrate phosphoribosyl isomerase A or priA gene, at which these pathways converge, appears to coevolve with the occurrence of trp and his genes. Characterization of a dozen PriA homologs shows that these enzymes adapt from bifunctionality in the largest genomes, to a monofunctional, yet not necessarily specialized, inefficient form in genomes undergoing reduction. These functional changes are accomplished via mutations, which result from relaxation of purifying selection, in residues structurally mapped after sequence and X-ray structural analyses. Our results show how gene loss can drive the evolution of substrate specificity from retained enzymes.


Assuntos
Actinomycetaceae/enzimologia , Actinomycetaceae/metabolismo , Adaptação Biológica , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/metabolismo , Deleção de Genes , Actinomycetaceae/genética , Evolução Molecular , Mutação , Especificidade por Substrato
13.
Biochem J ; 473(9): 1141-52, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26929404

RESUMO

We investigate the evolution of co-occurring analogous enzymes involved in L-tryptophan and L-histidine biosynthesis in Actinobacteria Phylogenetic analysis of trpF homologues, a missing gene in certain clades of this lineage whose absence is complemented by a dual-substrate HisA homologue, termed PriA, found that they fall into three categories: (i) trpF-1, an L-tryptophan biosynthetic gene horizontally acquired by certain Corynebacterium species; (ii) trpF-2, a paralogue known to be involved in synthesizing a pyrrolopyrrole moiety and (iii) trpF-3, a variable non-conserved orthologue of trpF-1 We previously investigated the effect of trpF-1 upon the evolution of PriA substrate specificity, but nothing is known about the relationship between trpF-3 and priA After in vitro steady-state enzyme kinetics we found that trpF-3 encodes a phosphoribosyl anthranilate isomerase. However, mutation of this gene in Streptomyces sviceus did not lead to auxothrophy, as expected from the biosynthetic role of trpF-1 Biochemical characterization of a dozen co-occurring TrpF-2 or TrpF-3, with PriA homologues, explained the prototrophic phenotype, and unveiled an enzyme activity trade-off between TrpF and PriA. X-ray structural analysis suggests that the function of these PriA homologues is mediated by non-conserved mutations in the flexible L5 loop, which may be responsible for different substrate affinities. Thus, the PriA homologues that co-occur with TrpF-3 represent a novel enzyme family, termed PriB, which evolved in response to PRA isomerase activity. The characterization of co-occurring enzymes provides insights into the influence of functional redundancy on the evolution of enzyme function, which could be useful for enzyme functional annotation.


Assuntos
Proteínas de Bactérias/genética , Evolução Molecular , Isomerases/genética , Streptomyces , Estrutura Secundária de Proteína , Streptomyces/enzimologia , Streptomyces/genética
14.
BMC Evol Biol ; 15: 107, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26058375

RESUMO

BACKGROUND: Current sequence-based approaches to identify enzyme functional shifts, such as enzyme promiscuity, have proven to be highly dependent on a priori functional knowledge, hampering our ability to reconstruct evolutionary history behind these mechanisms. Hidden Markov Model (HMM) profiles, broadly used to classify enzyme families, can be useful to distinguish between closely related enzyme families with different specificities. The (ßα)8-isomerase HisA/PriA enzyme family, involved in L-histidine (HisA, mono-substrate) biosynthesis in most bacteria and plants, but also in L-tryptophan (HisA/TrpF or PriA, dual-substrate) biosynthesis in most Actinobacteria, has been used as model system to explore evolutionary hypotheses and therefore has a considerable amount of evolutionary, functional and structural knowledge available. We searched for functional evolutionary intermediates between the HisA and PriA enzyme families in order to understand the functional divergence between these families. RESULTS: We constructed a HMM profile that correctly classifies sequences of unknown function into the HisA and PriA enzyme sub-families. Using this HMM profile, we mined a large metagenome to identify plausible evolutionary intermediate sequences between HisA and PriA. These sequences were used to perform phylogenetic reconstructions and to identify functionally conserved amino acids. Biochemical characterization of one selected enzyme (CAM1) with a mutation within the functionally essential N-terminus phosphate-binding site, namely, an alanine instead of a glycine in HisA or a serine in PriA, showed that this evolutionary intermediate has dual-substrate specificity. Moreover, site-directed mutagenesis of this alanine residue, either backwards into a glycine or forward into a serine, revealed the robustness of this enzyme. None of these mutations, presumably upon functionally essential amino acids, significantly abolished its enzyme activities. A truncated version of this enzyme (CAM2) predicted to adopt a (ßα)6-fold, and thus entirely lacking a C-terminus phosphate-binding site, was identified and shown to have HisA activity. CONCLUSION: As expected, reconstruction of the evolution of PriA from HisA with HMM profiles suggest that functional shifts involve mutations in evolutionarily intermediate enzymes of otherwise functionally essential residues or motifs. These results are in agreement with a link between promiscuous enzymes and intragenic epistasis. HMM provides a convenient approach for gaining insights into these evolutionary processes.


Assuntos
Bactérias/enzimologia , Bactérias/genética , Evolução Molecular , Isomerases/química , Isomerases/genética , Metagenoma , Bactérias/classificação , Sítios de Ligação , Histidina/biossíntese , Cadeias de Markov , Mutagênese Sítio-Dirigida , Filogenia , Especificidade por Substrato , Triptofano/biossíntese
15.
Acta Gastroenterol Latinoam ; 44(1): 39-44, 2014 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-24847628

RESUMO

INTRODUCTION: Among several regions in the world hepatic hydatidosis can be considered endemic. Currently there are many available treatments for this disease, been surgery the most effective one. Surgical procedures can be divided in two main groups, radical and non-radical procedures. The goal of this work is to evaluate the morbidity, mortality and percentage of recurrence in patients treated with hepatectomies, comparing them with other publications. MATERIAL AND METHODS: This retrospective study was carried out in a series from Spain and Argentina. We analyzed the following data: sex, age, type of resection, associated surgical gestures, presence of liver disease, operative time, blood transfusion, morbidity, mortality, hospital stay, re-hospitalization, recurrence and follow up. Dindo--Clavien classification was used for complications, and International Hepato-Pancreato-Biliary Association (IHPBA) Brisbane classification for hepatectomies. Mortality was considered until 90 days after surgery. To evaluate the recurence we only included patients followed over 6 months. RESULTS: Indications for liver resections were performed in patients with cysts larger than 5 centimeters, multiple cysts, large cysts, with bile duct communicated or suspicion of this communication. Five patients required blood transfusions (10%) with a median for these 5 patients of 740 ml and 74 ml for the complete series. The median operative time was 186 minutes (range 45 to 1,050 minutes). Median hospital stay was 7.7 days. Monitoring more than 6 months was conducted in 38 patients. CONCLUSIONS: We believe that hepatic hydatid disease is a multifaceted disease and requires more than one therapeutic approach. Hepatectomy with complete resection of the parasite offers the possibility of doing so in a controlled and safe way by experienced hands, ensuring good results in the treatment of this disease.


Assuntos
Equinococose Hepática/mortalidade , Equinococose Hepática/cirurgia , Hepatectomia , Adulto , Idoso , Argentina , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Espanha , Resultado do Tratamento
16.
Langenbecks Arch Surg ; 399(3): 307-14, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24526221

RESUMO

BACKGROUND: Laparoscopic resection is an emerging tool in surgical oncology, but its role in liver tumors is far from being universally accepted. METHODS: We designed a case-matched control study, comparing laparoscopic (LAP) vs. open hepatectomies (OP) performed in the same center during the same period of time. Fifty LAP were performed (34 liver metastases, 7 hepatocellular carcinomas, 2 hydatid cysts, and 5 benign tumors). Cases were compared with 100 OP matched according to: diagnosis, number of lesions, type of resection, age, ASA score, and ECOG performance status. We evaluated intraoperative and postoperative parameters, focusing on morbidity and mortality. RESULTS: Preoperative data were comparable in both groups. Operative features were similar in terms of overall morbidity 18 (36 %) vs. 36 (36 %), p = 1; intraoperative bleeding, 401 (18-2192) vs. 475 (20-2000) mL, p = 0.89; pedicle clamping, 37 (74 %) vs. 88 (88 %), p = 0.55; margin, 0.6 (0-5) vs. 0.65 (0-5) cm, p = 0.94, and mortality p = 0.65 for the LAP and OP groups, respectively. There was a significant decrease in surgical site infections 1 (2 %) vs. 18 (18 %) p = 0.007 in the LAP group. Operative time was longer: 295 (120-600) vs. 200 (70-450) min (p = 0.0001), and hospital stay significantly shorter: 4 (1-60) vs. 7 (3-44) days, p = 0.0001 with less readmissions (0 vs. 7 %) in the LAP. DISCUSSION: In adequately selected patients, laparoscopic hepatectomy is feasible, safe, shortens hospital stay, and decreases surgical site infections.


Assuntos
Hepatectomia , Laparoscopia , Tempo de Internação , Hepatopatias/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Hepatopatias/complicações , Hepatopatias/patologia , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Resultado do Tratamento
17.
Acta gastroenterol. latinoam ; 44(1): 39-44, 2014 Mar.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1157425

RESUMO

INTRODUCTION: Among several regions in the world hepatic hydatidosis can be considered endemic. Currently there are many available treatments for this disease, been surgery the most effective one. Surgical procedures can be divided in two main groups, radical and non-radical procedures. The goal of this work is to evaluate the morbidity, mortality and percentage of recurrence in patients treated with hepatectomies, comparing them with other publications. MATERIAL AND METHODS: This retrospective study was carried out in a series from Spain and Argentina. We analyzed the following data: sex, age, type of resection, associated surgical gestures, presence of liver disease, operative time, blood transfusion, morbidity, mortality, hospital stay, re-hospitalization, recurrence and follow up. Dindo--Clavien classification was used for complications, and International Hepato-Pancreato-Biliary Association (IHPBA) Brisbane classification for hepatectomies. Mortality was considered until 90 days after surgery. To evaluate the recurence we only included patients followed over 6 months. RESULTS: Indications for liver resections were performed in patients with cysts larger than 5 centimeters, multiple cysts, large cysts, with bile duct communicated or suspicion of this communication. Five patients required blood transfusions (10


) with a median for these 5 patients of 740 ml and 74 ml for the complete series. The median operative time was 186 minutes (range 45 to 1,050 minutes). Median hospital stay was 7.7 days. Monitoring more than 6 months was conducted in 38 patients. CONCLUSIONS: We believe that hepatic hydatid disease is a multifaceted disease and requires more than one therapeutic approach. Hepatectomy with complete resection of the parasite offers the possibility of doing so in a controlled and safe way by experienced hands, ensuring good results in the treatment of this disease.


Assuntos
Equinococose Hepática/cirurgia , Equinococose Hepática/mortalidade , Hepatectomia , Adulto , Argentina , Espanha , Estudos Retrospectivos , Feminino , Humanos , Idoso , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Seguimentos
18.
Acta Gastroenterol. Latinoam. ; 44(1): 39-44, 2014 Mar.
Artigo em Espanhol | BINACIS | ID: bin-133701

RESUMO

INTRODUCTION: Among several regions in the world hepatic hydatidosis can be considered endemic. Currently there are many available treatments for this disease, been surgery the most effective one. Surgical procedures can be divided in two main groups, radical and non-radical procedures. The goal of this work is to evaluate the morbidity, mortality and percentage of recurrence in patients treated with hepatectomies, comparing them with other publications. MATERIAL AND METHODS: This retrospective study was carried out in a series from Spain and Argentina. We analyzed the following data: sex, age, type of resection, associated surgical gestures, presence of liver disease, operative time, blood transfusion, morbidity, mortality, hospital stay, re-hospitalization, recurrence and follow up. Dindo--Clavien classification was used for complications, and International Hepato-Pancreato-Biliary Association (IHPBA) Brisbane classification for hepatectomies. Mortality was considered until 90 days after surgery. To evaluate the recurence we only included patients followed over 6 months. RESULTS: Indications for liver resections were performed in patients with cysts larger than 5 centimeters, multiple cysts, large cysts, with bile duct communicated or suspicion of this communication. Five patients required blood transfusions (10


) with a median for these 5 patients of 740 ml and 74 ml for the complete series. The median operative time was 186 minutes (range 45 to 1,050 minutes). Median hospital stay was 7.7 days. Monitoring more than 6 months was conducted in 38 patients. CONCLUSIONS: We believe that hepatic hydatid disease is a multifaceted disease and requires more than one therapeutic approach. Hepatectomy with complete resection of the parasite offers the possibility of doing so in a controlled and safe way by experienced hands, ensuring good results in the treatment of this disease.


Assuntos
Equinococose Hepática/mortalidade , Equinococose Hepática/cirurgia , Hepatectomia , Adulto , Idoso , Argentina , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Espanha , Resultado do Tratamento
19.
Cir. Esp. (Ed. impr.) ; 89(4): 230-236, abr. 2011. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-92675

RESUMO

Introducción La estenosis significativa del tronco celiaco habitualmente cursa de forma asintomática. No obstante, cuando se interrumpe la arcada de las arterias pancreatoduodenales, puede producirse isquemia visceral. El objetivo de este estudio es determinar si la estenosis preoperatoria del tronco celiaco es un factor de riesgo de complicaciones en pacientes sometidos a duodenopancreatectomía (DPC). Material y métodos Hemos analizado retrospectivamente a 58 pacientes consecutivos sometidos a DPC. Hemos relacionado la estenosis significativa del tronco celiaco con la evolución posquirúrgica. En todos los casos se ha realizado un estudio mediante tomografía computarizada multidetector (TCDM) de 16 canales en tres fases hepáticas. Hemos revisado la TCDM prequirúrgica centrándonos en la morfología del tronco celiaco, especialmente la presencia o ausencia de estenosis significativa (> 50%).Resultados Encontramos estenosis del tronco celiaco > 50% en 13 pacientes (22%). La mortalidad total fue de 3 pacientes (5%). La morbilidad total fue del 62%. En 16 pacientes (28%) hubo complicaciones graves, de los que 8 (62%) pertenecen al grupo de estenosis significativa del tronco celiaco (p=0,004); 10 pacientes (17%) presentaron fístula pancreática, 5 (38%) vs. 5 (11%) (p=0,036); 14 pacientes (24%) necesitaron reoperación, 7 (54%) vs. 7 (16%) (p=0,009); 7 pacientes (12%) presentaron hemoperitoneo, 4 (31%) vs. 3 (7%) (p=0,038), en los grupos con y sin estenosis del tronco celiaco respectivamente. Conclusiones La estenosis radiológicamente significativa del tronco celiaco es un factor de riesgo de complicaciones graves tras DPC. El estudio del calibre de la AMS con TCDM debería ser sistemático antes de una DPC. Debería valorarse preoperatoriamente la corrección de la estenosis significativa del tronco celiaco (AU)


Introduction Significant celiac trunk or artery stenosis (CAS) is normally asymptomatic. However, when the arteries of the pancreatoduodenal arcade are occluded, it could trigger avisceral ischaemia. The objective of this study is to determine whether preoperative CAS is a risk factor for developing complications in patients subjected to duodenopancreatectomy(DPC). Material and methods: We have retrospectively analysed 58 consecutive patients subjected to DPC. We have associated significant CAS with post-surgical outcome. In all cases a 16-channel multidetector computed tomography (MDCT) in three hepatic phases was performed. We have reviewed the pre-surgical MDCT focusing on the morphology of the celiacartery (CA), particularly in the presence or absence of significant stenosis (>50%). Results: We found CAS >50% in 13 patients (22%). The overall mortality was 5% (3 patients). Serious complications developed in 16 (28%) patients, 8 (62%) of whom belonged to the group with significant CAS (P = .004). Ten patients (17%) had a pancreatic fistula, 5 (38%) vs. 5 (11%)(P = .036); Fourteen patients (24%) needed new surgery, 7 (54%) vs. 7 (16%) (P = .009); Seven patients (12%) had a haemoperitoneum, 4 (31%) vs. 3 (7%) (P = .038), in the group with and without CAS, respectively. Conclusions: Significant radiological CAS is a risk factor of serious complications after DPC. The study of the calibre of the superior mesenteric artery (SMA) with MDCT should beroutine before a DPC. The correction of a significant CAS should be evaluated preoperatively (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Arteriopatias Oclusivas/complicações , Artéria Celíaca , Pancreaticoduodenectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Risco
20.
Cir Esp ; 89(4): 230-6, 2011 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-21349503

RESUMO

INTRODUCTION: Significant celiac trunk or artery stenosis (CAS) is normally asymptomatic. However, when the arteries of the pancreatoduodenal arcade are occluded, it could trigger a visceral ischaemia. The objective of this study is to determine whether preoperative CAS is a risk factor for developing complications in patients subjected to duodenopancreatectomy (DPC). MATERIAL AND METHODS: We have retrospectively analysed 58 consecutive patients subjected to DPC. We have associated significant CAS with post-surgical outcome. In all cases a 16-channel multidetector computed tomography (MDCT) in three hepatic phases was performed. We have reviewed the pre-surgical MDCT focusing on the morphology of the celiac artery (CA), particularly in the presence or absence of significant stenosis (>50%). RESULTS: We found CAS >50% in 13 patients (22%). The overall mortality was 5% (3 patients). Serious complications developed in 16 (28%) patients, 8 (62%) of whom belonged to the group with significant CAS (P=.004). Ten patients (17%) had a pancreatic fistula, 5 (38%) vs. 5 (11%) (P=.036); Fourteen patients (24%) needed new surgery, 7 (54%) vs. 7 (16%) (P=.009); Seven patients (12%) had a haemoperitoneum, 4 (31%) vs. 3 (7%) (P=.038), in the group with and without CAS, respectively. CONCLUSIONS: Significant radiological CAS is a risk factor of serious complications after DPC. The study of the calibre of the superior mesenteric artery (SMA) with MDCT should be routine before a DPC. The correction of a significant CAS should be evaluated preoperatively.


Assuntos
Arteriopatias Oclusivas/complicações , Artéria Celíaca , Pancreaticoduodenectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
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