Oxygen and RNA in stress-induced mutation.

Mechanisms of mutation upregulated by stress responses have been described in several organisms from bacteria to human. These mechanisms might accelerate genetic change specifically when cells are maladapted to their environment. Stress-induced mutation mechanisms differ in their genetic requirements from mutation in growing cells, occurring by different mechanisms in different assay systems, but having in common a requirement for the induction of stress-responses. Here, we review progress in two areas relevant to stress-response-dependent mutagenic DNA break repair mechanisms in Escherichia coli. First, we review evidence that relates mutation to transcription. This connection might allow mutagenesis in transcribed regions, including those relevant to any stress being experienced, opening the possibility that mutations could be targeted to regions where mutation might be advantageous under conditions of a specific stress. We review the mechanisms by which replication initiated by transcription can lead to mutation. Second, we review recent findings that, although stress-induced mutation does not require exogenous DNA-damaging agents, it does require the presence of damaged bases in DNA. For starved E. coli, endogenous oxygen radicals cause these altered bases. We postulate that damaged bases stall the replisome, which, we suggest, is required for DNA-polymerase exchange, allowing the action of low-fidelity DNA polymerases that promote mutation.

Persistent damaged bases in DNA allow mutagenic break repair in Escherichia coli.

Bacteria, yeast and human cancer cells possess mechanisms of mutagenesis upregulated by stress responses. Stress-inducible mutagenesis potentially accelerates adaptation, and may provide important models for mutagenesis that drives cancers, host pathogen interactions, antibiotic resistance and possibly much of evolution generally. In Escherichia coli repair of double-strand breaks (DSBs) becomes mutagenic, using low-fidelity DNA polymerases under the control of the SOS DNA-damage response and RpoS general stress response, which upregulate and allow the action of error-prone DNA polymerases IV (DinB), II and V to make mutations during repair. Pol IV is implied to compete with and replace high-fidelity DNA polymerases at the DSB-repair replisome, causing mutagenesis. We report that up-regulated Pol IV is not sufficient for mutagenic break repair (MBR); damaged bases in the DNA are also required, and that in starvation-stressed cells, these are caused by reactive-oxygen species (ROS). First, MBR is reduced by either ROS-scavenging agents or constitutive activation of oxidative-damage responses, both of which reduce cellular ROS levels. The ROS promote MBR other than by causing DSBs, saturating mismatch repair, oxidizing proteins, or inducing the SOS response or the general stress response. We find that ROS drive MBR through oxidized guanines (8-oxo-dG) in DNA, in that overproduction of a glycosylase that removes 8-oxo-dG from DNA prevents MBR. Further, other damaged DNA bases can substitute for 8-oxo-dG because ROS-scavenged cells resume MBR if either DNA pyrimidine dimers or alkylated bases are induced. We hypothesize that damaged bases in DNA pause the replisome and allow the critical switch from high fidelity to error-prone DNA polymerases in the DSB-repair replisome, thus allowing MBR. The data imply that in addition to the indirect stress-response controlled switch to MBR, a direct cis-acting switch to MBR occurs independently of DNA breakage, caused by ROS oxidation of DNA potentially regulated by ROS regulators.

Identification of Patients with Myocardial Infarction. Vectorcardiographic and Electrocardiographic Analysis.

BACKGROUND: The largest morbidity and mortality group worldwide continues to be that suffering Myocardial Infarction (MI). The use of vectorcardiography (VCG) and electrocardiography (ECG) has improved the diagnosis and characterization of this cardiac condition. OBJECTIVES: Herein, we applied a novel ECG-VCG combination technique to identifying 95 patients with MI and to differentiating them from 52 healthy reference subjects. Subsequently, and with a similar method, the location of the infarcted area permitted patient classification. METHODS: We analyzed five depolarization and four repolarization indexes, say: a) volume; b) planar area; c) QRS loop perimeter; d) QRS vector difference; e - g) Area under the QRS complex, ST segment and T-wave in the (X, Y, Z) leads; h) ST-T Vector Magnitude Difference; i) T-wave Vector Magnitude Difference; and j) the spatial angle between the QRS complex and the T-wave. For classification, patients were divided into two groups according to the infarcted area, that is, anterior or inferior sectors (MI-ant and MI-inf, respectively). RESULTS: Our results indicate that several ECG and VCG parameters show significant differences (p-value<0.05) between Healthy and MI subjects, and between MI-ant and MI-inf. Moreover, combining five parameters, it was possible to classify the MI and healthy subjects with a sensitivity = 95.8%, a specificity = 94.2%, and an accuracy = 95.2%, after applying a linear discriminant classifier method. Similarly, combining eight indexes, we could separate out the MI patients in MI-ant vs MI-inf with a sensitivity = 89.8%, 84.8%, respectively, and an accuracy = 89.8%. CONCLUSIONS: The new multivariable MI patient identification and localization technique, based on ECG and VCG combination indexes, offered excellent performance to differentiating populations with MI from healthy subjects. Furthermore, this technique might be applicable to estimating the infarcted area localization. In addition, the proposed method would be an alternative diagnostic technique in the emergency room.

The DNA polymerase III holoenzyme contains γ and is not a trimeric polymerase.

There is widespread agreement that the clamp loader of the Escherichia coli replicase has the composition DnaX3δδ'χψ. Two DnaX proteins exist in E. coli, full length τ and a truncated γ that is created by ribosomal frameshifting. τ binds DNA polymerase III tightly; γ does not. There is a controversy as to whether or not DNA polymerase III holoenzyme (Pol III HE) contains γ. A three-τ form of Pol III HE would contain three Pol IIIs. Proponents of the three-τ hypothesis have claimed that γ found in Pol III HE might be a proteolysis product of τ. To resolve this controversy, we constructed a strain that expressed only τ from a mutated chromosomal dnaX. γ containing a C-terminal biotinylation tag (γ-C(tag)) was provided in trans at physiological levels from a plasmid. A 2000-fold purification of Pol III* (all Pol III HE subunits except ß) from this strain contained one molecule of γ-C(tag) per Pol III* assembly, indicating that the dominant form of Pol III* in cells is Pol III2τ2 γδδ'χψ. Revealing a role for γ in cells, mutants that express only τ display sensitivity to ultraviolet light and reduction in DNA Pol IV-dependent mutagenesis associated with double-strand-break repair, and impaired maintenance of an F' episome.

Evolutionary transgenomics: prospects and challenges.

Many advances in our understanding of the genetic basis of species differences have arisen from transformation experiments, which allow us to study the effect of genes from one species (the donor) when placed in the genetic background of another species (the recipient). Such interspecies transformation experiments are usually focused on candidate genes - genes that, based on work in model systems, are suspected to be responsible for certain phenotypic differences between the donor and recipient species. We suggest that the high efficiency of transformation in a few plant species, most notably Arabidopsis thaliana, combined with the small size of typical plant genes and their cis-regulatory regions allow implementation of a screening strategy that does not depend upon a priori candidate gene identification. This approach, transgenomics, entails moving many large genomic inserts of a donor species into the wild type background of a recipient species and then screening for dominant phenotypic effects. As a proof of concept, we recently conducted a transgenomic screen that analyzed more than 1100 random, large genomic inserts of the Alabama gladecress Leavenworthia alabamica for dominant phenotypic effects in the A. thaliana background. This screen identified one insert that shortens fruit and decreases A. thaliana fertility. In this paper we discuss the principles of transgenomic screens and suggest methods to help minimize the frequencies of false positive and false negative results. We argue that, because transgenomics avoids committing in advance to candidate genes it has the potential to help us identify truly novel genes or cryptic functions of known genes. Given the valuable knowledge that is likely to be gained, we believe the time is ripe for the plant evolutionary community to invest in transgenomic screens, at least in the mustard family Brassicaceae where many species are amenable to efficient transformation.

Novel technique for ST-T interval characterization in patients with acute myocardial ischemia.

BACKGROUND: The novel signal processing techniques have allowed and improved the use of vectorcardiography (VCG) to diagnose and characterize myocardial ischemia. Herein, we studied vectorcardiographic dynamic changes of ventricular repolarization in 80 patients before (control) and during Percutaneous Transluminal Coronary Angioplasty (PTCA). METHODS: We propose four vectorcardiographic ST-T parameters, i.e., (a) ST Vector Magnitude Area (aSTVM); (b) T-wave Vector Magnitude Area (aTVM); (c) ST-T Vector Magnitude Difference (ST-TVD), and (d) T-wave Vector Magnitude Difference (TVD). For comparison, the conventional ST-Change Vector Magnitude (STCVM) and Spatial Ventricular Gradient (SVG) were also calculated. RESULTS: Our results indicate that several vectorcardiographic parameters show significant differences (p-value<0.05) before starting and during PTCA. Statistical minute-by-minute PTCA comparison against the control situation showed that ischemic monitoring reached a sensitivity=90.5% and a specificity=92.6% at the 5th minute of the PTCA, when aSTVM and ST-TVD were used as classifiers. CONCLUSIONS: We conclude that the sensitivity and specificity for acute ischemia monitoring could be increased with the use of only two vectorcardiographic parameters. Hence, the proposed technique based on vectorcardiography could be used in addition to the conventional ST-T analysis for better monitoring of ischemic patients.

Perfil e avaliação dos resultados de pacientes submetidas à mamoplastia redutora / Patient profile and results evaluation after breast reduction

INTRODUÇÃO: A hipertrofia mamária é relatada como fonte de sofrimento físico e emocional em mulheres, sendo que diversas técnicas vêm sendo descritas para seu tratamento. OBJETIVO: Demonstrar o perfil e resultados satisfatórios da mamoplastia redutora no tratamento de hipertrofias mamárias pela classificação de Bozola. MÉTODO: Estudo descritivo e retrospectivo, com 94 pacientes submetidas àmamoplastia redutora, entre janeiro de 2011 e outubro de 2013, avaliadas segundo idade, queixa principal, comorbidades, índice de massa corporal (IMC), maternidade prévia, flacidez de pele, contorno e consistência mamária, tumorações, graus de hipertrofia submetidas à mamoplastia com a técnica de Ariê e Peixoto, com pedículo I de Lyacir Ribeiro, e a técnica de Pitanguy. No pós-operatório as pacientes foram avaliadas quanto à satisfação dos resultados observados pela simetria das mamas, tamanho, complicações e sensibilidade do complexo areolopapilar (CAP). RESULTADOS: A média de idade das pacientes foi de 28,5 anos e IMC médio de 27,66. A principal queixa foi de desconforto e quadro doloroso em 73,4%. Média de tecido total ressecado foi de 952,5 g. Foi evidenciado taxa de complicação em 27,6%. O avaliador considerou forma, simetria e sensibilidade do CAP. A satisfação, quanto ao procedimento, foi evidenciada como ótima em 51,1% dos casos, e boa em 35,1%. CONCLUSÃO: As técnicas de Ariê e Peixoto, com pedículo inferior, e de Pitanguy promoveram resultados duradouros com maior prazo de sustentação da mama, além de um polo superior medial desenhado com curvas mais acentuadas.

Introduction: In women, breast hypertrophy is a source of physical and emotional pain; several techniques have been described for its treatment. Objective: To demonstrate the appearance and satisfactory results obtained with reductive mammoplasty for the treatment of breast hypertrophy according to Bozola's classification. Method: This descriptive and retrospective study included 94 patients who underwent reductive mammoplasty between January 2011 and October 2013. The patients were evaluated according to age, chief complaint, comorbidities, body mass index (BMI), history of pregnancy, presence of sagging skin, breast contour and consistency, tumors, and hypertrophy grade. The patients underwent reductive mammoplasty using the technique of Ariê and Peixoto with the type I pedicle of Ribeiro as well as Pitanguy's method. During the postoperative period, patient satisfaction was evaluated according to the outcomes observed and regarding breast symmetry, size, complications, and nipple-areola complex (NAC) sensitivity. Results: The average patient age was 28.5 years and the average BMI was 27.66. The main complaint was discomfort and pain (73.4%). The average weight of resected tissue was 952.5 g. The occurrence of complications was observed in 27.6% of patients. For the evaluation, form, symmetry and NAC sensitivity were considered. The satisfaction rate was great in 51.1% of cases and good in 35.1%. Conclusion: The technique of Ariê and Peixoto as well as Pitanguy's method provided long-term results with durable breast support and enabled the design of a medial upper pole with more pronounced contours.

Acute myocardial ischemia monitoring before and during angioplasty by a novel vectorcardiographic parameter set.

BACKGROUND: This work evaluates the vectorcardiographic dynamic changes in ischemic patients before and during Percutaneous Transluminal Coronary Angioplasty (PTCA). METHODS: Four QRS-loop parameters were computed in 51 ischemic and 52 healthy subjects with the objective of assessing the vectorcardiographic differences between both groups: maximum vector magnitude (QRS(mVM)), planar area (QRS(PA)), maximum distance between centroid and loop (QRS(mDCL)) and perimeter (QRS(P)).The conventional ST-change vector magnitude (STC(VM)), QRS-vector difference (QRS(VD)) and spatial ventricular gradient (SVG) were also calculated. RESULTS: Statistical minute-by-minute PTCA comparison against a healthy population showed that ischemic patients monitoring is greatly enhanced when all the QRS-loop parameters, in combination with the standard STC(VM), QRS(VD) and SVG indexes, are used in the classification. Sensitivity and Specificity, in turn, reached rather high values, 95.4% and 95.2%, respectively. CONCLUSIONS: These new vectorcardiographic set of complementary QRS-loop parameters, when combined with the classics STC(VM), QRS(VD) and SVG indexes, increase sensitivity and specificity for acute ischemia monitoring.

Novel set of vectorcardiographic parameters for the identification of ischemic patients.

New signal processing techniques have enabled the use of the vectorcardiogram (VCG) for the detection of cardiac ischemia. Thus, we studied this signal during ventricular depolarization in 80 ischemic patients, before undergoing angioplasty, and 52 healthy subjects with the objective of evaluating the vectorcardiographic difference between both groups so leading to their subsequent classification. For that matter, seven QRS-loop parameters were analyzed, i.e.: (a) Maximum Vector Magnitude; (b) Volume; (c) Planar Area; (d) Maximum Distance between Centroid and Loop; (e) Angle between XY and Optimum Plane; (f) Perimeter and, (g) Area-Perimeter Ratio. For comparison, the conventional ST-Vector Magnitude (ST(VM)) was also calculated. Results indicate that several vectorcardiographic parameters show significant differences between healthy and ischemic subjects. The identification of ischemic patients via discriminant analysis using ST(VM) produced 73.2% Sensitivity (Sens) and 73.9% Specificity (Spec). In our study, the QRS-loop parameter with the best global performance was Volume, which achieved Sens=64.5% and Spec=74.6%. However, when all QRS-loop parameters and ST(VM) were combined, we obtained Sens=88.5% and Spec=92.1%. In conclusion, QRS loop parameters can be accepted as a complement to conventional ST(VM) analysis in the identification of ischemic patients.

An assessment of transgenomics as a tool for identifying genes involved in the evolutionary differentiation of closely related plant species.

• Transgenomics is the process of introducing genomic clones from a donor species into a recipient species and then screening the resultant transgenic lines for phenotypes of interest. This method might allow us to find genes involved in the evolution of phenotypic differences between species as well as genes that have the potential to contribute to reproductive isolation: potential speciation genes. • More than 1100 20-kbp genomic clones from Leavenworthia alabamica were moved into Arabidopsis thaliana by transformation. After screening a single primary transformant for each line, clones associated with mutant phenotypes were tested for repeatability and co-segregation. • We found 84 clones with possible phenotypic effects, of which eight were repeatedly associated with the same phenotype. One clone, 11_11B, co-segregated with a short fruit phenotype. Further study showed that 11_11B affects seed development, with as much as one-third of the seeds aborted in some fruit. • Transgenomics is a viable strategy for discovering genes of evolutionary interest. We identify methods to reduce false positives and false negatives in the future. 11_11B can be viewed as a potential speciation gene, illustrating the value of transgenomics for studying the molecular basis of reproductive isolation.

Sentimentos vivenciados por graduandos em enfermagem durante o estágio supervisionado / Feelings experienced by nursing students during supervised training / Sentimientos experimentados por los estudiantes de enfermería durante el periodo de practicas

Objetivo: identificar os sentimentos vivenciados pelos alunos durante o Estágio Supervisionado em Enfermagem; caracterizando-os quanto o perfil socioeconômico, correlacionando os sentimentos vivenciados durante a aprendizagem teórico-prático, e às interferências no processo ensino–aprendizagem. Método: estudo de abordagem quali-quantitativa de natureza descritiva e epidemiológica, utilizamos um instrumento semi-estruturado, realizado com os acadêmicos do oitavo e nono períodos do Curso de Graduação em Enfermagem de uma Universidade privada do Sul de Minas Gerais, após aprovação da instituição de ensino e do Comitê de Ética em Pesquisa (0118.0.213.000-09). Resultados: a análise dos dados quantitativos foi através da estatística descritiva e os qualitativos através da Análise de Conteúdo de Bardin. Os resultados revelaram que a maioria dos alunos tinha idades entre 22 e 26 anos; eram do sexo feminino, solteiros, sem filhos e não trabalhavam na área, além disso, os resultados expuseram que o curso de enfermagem havia sido a primeira opção na hora da escolha do curso. Do total, 16 (23,9%) já pensaram em desistir por falta de tempo para se dedicar ao mesmo. Em relação aos sentimentos vivenciados durante o estágio supervisionado, emergiram duas categorias: Satisfação, sentimentos de utilidade social e Sentimentos conflitantes. Quanto aos sentimentos em relação ao curso e à vida profissional surgiram Sentimentos de temor, Sentimentos contraditórios e de Satisfação. Conclusão: recomenda-se que as instituições de ensino despertem nos docentes sobre importância da interação com os acadêmicos na melhora do ensino aprendizagem, e que os alunos possam ter apoio psicopedagógicos durante a graduação, para que minimizem o sofrimento auxiliando-os durante os conflitos vivenciados.(AU)

Objective: to identify the feelings experienced by students during supervised training in Nursing, characterizing them according to their socioeconomic characteristics, correlating the feelings experienced during the theoretical and practical learning, and towards the interference in the teaching-learning process. Method: this descriptive, epidemiology, qualiquantitative study was performed using a semi-structured instrument. It was conducted with eighth- and ninth-semester nursing undergraduates of a private university in Southern Minas Gerais. The study was approved by the institution and the respective Research Ethics Review Board (0118.0.213.000-09). Results: the quantitative data were analyzed using descriptive statistics, while Bardin's content analysis was used for the qualitative data. Most students were between 22 to 26 years old, female, unmarried, without children and not working in the nursing area. In addition, it was revealed that the nursing program had been the student's first choice among university courses. Of the total, 16 (23.9%) have thought about quitting because of a lack of time. In relation to the feelings experienced during the supervised training, two categories emerged: satisfaction, feelings of social utility and conflicting feelings. As for the subjects' feelings towards the course and professional life, the following categories emerged: Feelings of fear, contradictory feelings, and feelings of satisfaction. Conclusion: educational institutions should build faculty awareness regarding the effect that student interaction has on improving the teaching-learning process, and that students should receive psychopedagogical support to minimize suffering by helping them during conflicts.(AU)

Objetivo: identificar los sentimientos experimentados por los estudiantes durante el periodo de practicas en Enfermería, caracterizándolos como el socioeconómico, la correlación de los sentimientos experimentados durante el aprendizaje teórico-práctico, y la injerencia en el proceso de enseñanza-aprendizaje. Método: se trata de un enfoque de la investigación epidemiológica cualitativo-cuantitativo y descriptivo, se utiliza un instrumento semi-estructurado. Se llevó a cabo con los estudiantes del octavo semestre y el noveno de la enfermería de una universidad privada del sur de Minas Gerais, después de la aprobación por la institución y el Comité de Ética de la Investigación (0118.0.213.000-09). Resultados: el análisis cuantitativo, mediante estadística descriptiva y datos cualitativos a través del análisis de contenido de Bardin. Los resultados revelaron que la mayoría de los estudiantes tenían entre 22 y 26 años, sexo femenino, soltera, sin hijos y no trabajan en la zona, además, los resultados mostraron que el programa de enfermería había sido la primera opción en el momento de elección, por supuesto. Del total, 16 (23,9%) han pensado en dejar de fumar debido a la falta de tiempo para dedicarse a ella. En relación a los sentimientos experimentados durante el entrenamiento supervisado, emergieron dos categorías: la satisfacción, el sentimiento de utilidad social y los sentimientos en conflicto. En cuanto a los sentimientos hacia el campo y llegó a la vida sentimientos de miedo, sentimientos de satisfacción y contradictorias. Conclusión: se recomienda que las instituciones educativas a raíz de la importancia de la interacción docente con los estudiantes en la mejora de la enseñanza y el aprendizaje y que los estudiantes pueden tener durante su psicología de la educación de pregrado, para minimizar el sufrimiento, ayudándoles en los conflictos con experiencia.(AU)

Possible contributions of TERMINAL FLOWER 1 to the evolution of rosette flowering in Leavenworthia (Brassicaceae).

Leavenworthia crassa is a rosette flowering species that differs from inflorescence flowering species, such as Arabidopsis thaliana, in having elongated pedicels and shortened interfloral internodes on the main axis. Based on previous experiments, we hypothesized that changes to the L. crassa TFL1 ortholog, LcrTFL1, were important in the evolution of rosette flowering. We isolated LcrTFL1 and introduced a genomic construct into tfl1 mutant A. thaliana plants. We also generated and analyzed EGFP-LcrTFL1 reporter-fusion lines, and LcrTFL1/LcrLFY doubly transgenic lines. The transgene rescued the mutant defects, but manifested gain-of-function phenotypes. However, LcrTFL1 lines differed from 35S:TFL1 lines in several regards. Defects in floral meristem identity establishment were observed, as was the production of flowers with extra petals. We also noted features that resemble rosette flowering: LcrTFL1 lines produced significantly shorter interfloral internodes and significantly longer pedicels than either wild-type or 35S:TFL1 plants. Our data show that there are substantive differences in the regulation and/or function of TFL1 orthologs between A. thaliana and L. crassa. These may reflect changes that occurred during the evolution of rosette flowering in Leavenworthia, but, if so, our results show that additional, as-yet-unidentified genes were involved in this instance of architectural evolution.

Analysis of QRS loop in the Vectorcardiogram of patients with Chagas' disease.

In the present work, we have studied the QRS loop in the Vectorcardiogram (VCG) of 95 chronic chagasic patients classified in different groups (I, II and III) according to their degree of myocardial damage. For comparison, the VCGs of 11 healthy subjects used as control group (Group O) were also examined. The QRS loop was obtained for each patient from the XYZ orthogonal leads of their High-Resolution Electrocardiogram (HRECG) records. In order to analyze the variations of QRS loop in each detected beat, it has been proposed in this study the following vectorcardiographic parameters a) Maximum magnitude of the cardiac depolarization vector, b) Volume, c) Area of QRS loop, d) Ratio between the Area and Perimeter, e) Ratio between the major and minor axes of the QRS loop and f) QRS loop Energy. It has been found that one or more indexes exhibited statistical differences (p < 0.05) between groups 0-II, O-III, I-II, I-III and II-III. We concluded that the proposed method could be use as complementary diagnosis technique to evaluate the degree of myocardial damage in chronic chagasic patients.

Analysis of QRS loop changes in the beat-to-beat Vectocardiogram of ischemic patients undergoing PTCA.

In the present work, we have studied dynamic changes of QRS loop in the Vectocardiogram (VCG) of 80 patients that underwent Percutaneous Transluminal Coronary Angioplasty (PTCA). The VCG was obtained for each patient using the XYZ orthogonal leads of their electrocardiographic (ECG) records acquired before, during and after PTCA procedure. In order to analyze the variations of VCG, it has been proposed in this study the following parameters a) Maximum module of the cardiac depolarization vector, b) Volume, c) and Area of vectocardiographic loop corresponding to the QRS complex of each beat, d) Maximum distance between Centroid and the Loop, e) Angle between the XY plane and the Optimum Plane, f) Relation between the Area and Perimeter. The results obtained indicate that the parameters proposed show significant statistics differences (p-value<0.05) before, during (with some exceptions at the first minute of balloon inflation) and after PTCA. We conclude that the variations observed in the proposed parameters correctly represent not only the morphological changes in the depolarization VCG but also they reflect the modifications in the levels of cardiac ischemia induced by PTCA.

Pólipos vesiculares: segundo taller de consenso de la Asociación Chilena de Hepatología / Gallbladder polyps: second consensus workshop of the chilean hepatology association

During workshop, hepatologists analyzed and gave recomendations about gallbladder polyps. They arrived to the following agreements: gallbladder polyps of less than 10 mm should be followed with ultrasonography at 3, 6 and 12 months if there is no enlargement. If there is enlargement, a cholecystectomy should be performed. Polyps larger than 10 mm should be subjected to cholecystectomy

Resultados alejados del tratamiento de las estenosis benignas recidivadas de la vía biliar proximal, tipo IV, mediante el injerto mucoso y tutor transhepatoyeyunal recambiable en U / Far results in the treatment of the recidivated proximal biliary tract benign stenosis, type IV, by means of an U transhepatojejunal tutor and mucosal anastomosis

Existe un grupo de pacientes en quienes, por sus características particulares, no se puede efectuar una anastomosis biliodigestiva formal. Para estos casos se han ideado numerosas técnicas quirúrgicas alternativas entre las cuales destaca la anastomosis biliodigestiva con tutor en U transhepatoyeyunal e injerto mucoso. Entre enero de 1982 y diciembre de 1986 fueron tratados 20 pacientes (18 mujeres y 2 hombres) con el diagnóstico de estenosis benigna recidivada de la vía biliar proximal tipo IV, en los que se usó como técnica de reparación el injerto mucoso con tutor transhepatoyeyunal según la técnica de Wexler y Smith. Al momento de esta revisión existían 16 pacientes vivos con un período de seguimiento mayor de 3 años en la mayoría de ellos. Hubo recidiva de las estenosis en un caso y de los cuatro casos fallecidos sólo uno puede ser atribuído al fracaso de la técnica quirúrgica

Pulmonary tuberculosis in an infant with AIDS: a case report

Reportamos el caso de un infante de nueve meses de edad referído al Hospital Pediátrico Universitario con pulmonía. En admisión el paciente presentó angustia respiratoria, linfadenipatía generalizada y hepatoesplenomegalia. Infección simultánea con Mycobacterium tuberculosis y el Virus de Immunodeficiencia Humana (HIV) fue documentada. La epidemiología, el diagnóstico y manejo de niños con el Síndrome de Immunodeficiencia Adquirida (SIDA) se discuten, se presentan recomendaciones en el manejo de niños con infección combinada de HIV y tuberculosis