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E Burgos

Publications and source records attributed to E Burgos.

At least 19 recordsLinked to original sources
PubMed2006

Organ changes and bacterial translocation in a rat model of chronic rejection after small bowel transplantation.

UNLABELLED: Rejection after small bowel transplantation (SBTx) may allow bacterial translocation damaging the liver and lungs. This study investigated these issues in a rat model of chronic rejection. MATERIALS AND METHODS: Orthotopic SBTx was performed in syngeneic (SYN) (ACI-ACI, n=8) and allogeneic (ALLO) (ACI-Lewis, n=8) rat strain combinations. Cyclosporine was given to ALLO rats for 28 days. Animals were sacrified between 55 and 65 days. Lymph nodes and venous samples were cultured; Escherichia coli DNA was assessed by polymerase chain reaction. We measured intestine, liver, spleen, and lung protein and DNA contents. Chronic rejection was histologically confirmed. RESULTS: Two of eight and four of eight rats died in the first week after SYN and ALLO SBTx, respectively. There were no differences in organ weights or DNA and protein contents compared with the controls. Gram-negative enteric bacteria were found in two of four ALLO and two of six SYN rats (ns), and aerobic gram-positive were found in two of four and two of six (ns), respectively. Anaerobic growth occurred in mesenteric lymph nodes in only one ALLO rat. E. coli DNA was negative in all animals. Lungs were severely emphysematous in ALLO rats with no histologic changes observed in the other phagocytic organs. Mild rejection was found in the intestine of ALLO rats. CONCLUSIONS: Bowel lesions in ALLO rats might be consistent with chronic rejection and lung lesions could be related to bacterial translocation after SBTx. However, contrary to our expectations, no significant bacterial translocation was demonstrated in either group at the end of the experiments.

Animals↗
PubMed2005

[Aplication of a 3D reconstruction model for the analysis of nitrofen induced intrathoracic malformations].

BACKGROUND: Three dimensional computer-assisted reconstruction offers some adventages for analysis and comparison of biological phenomena and anatomical structures. The CDH nitrofen-induced animal model associates multiple anomalies in neural-crest derived tissues. The goal of this study is to analyse by a 3-D reconstruction software the malformations in the extrinsic innervation of the esophagus in this model. METHODS: Nine control fetuses from 4 dams and 9 fetuses with CDH from 7 dams were studied. A thoracic block from the larynx to tracheal bifurcation was serially sectioned in the horizontal plane in every embryo. One in every 10 sections was stained with HE. The image was digitalized using biological software (TDR-3dbase). Vagus and recurrent laryngeal nerves, trachea, esophagus and the great vessels were examined. In order to obtain the 3-D reconstructions, 90 to 120 consecutive images were used. RESULTS: In comparison with controls there were striking abnormalities of these nerves in fetuses with CDH: 1) Absence of the left (2/9) or right (2/9) vagus nerves. 2) Absence of the left (3/9) or right (3/9) recurrent laryngeal nerves. 3) Marked hypoplasia of the trunk of the vagus (2/9). 4) Deviations of their normal course and change of normal anatomical relationships into the mediastinum (2/9). CONCLUSIONS: To fullfill our goals 3-D reconstructions allow a detailed analysis and provide a precise insight into the real anatomy. Rat fetuses with CDH have anomalies of the vagus and recurrent laryngeal nerves that support the concept of a neural crest involvement in the origin of this malformation. These observations may explain esophageal motility disorders in CDH.

Animals↗
PubMed2004

Bacterial translocation in acute rejection after small bowel transplantation in rats.

Acute rejection after small bowel transplantation (SBTx) may facilitate bacterial translocation (BT) and subsequent changes in the liver, spleen, and lungs. This study investigated whether BT occurs after acute rejection and whether this is followed by changes in the structure of the intestine and the phagocytic organs interposed between the gut and the general circulation. Orthotopic SBTx was performed in allogeneic (ALLO) rat-strain combinations (BN-Wistar, n=5). For comparison we used syngeneic SBTx (SYN) (BN-BN, n=6) controls. Animals were sacrificed on postoperative day 7. Mesenteric lymph nodes and portal and caval blood were cultured for aerobes and anaerobes. Escherichia coli beta-galactosidase DNA was assessed by polymerase chain reaction in the blood samples. Intestine, liver, spleen, and lung protein and DNA contents were measured. Histologic changes were graded according to standard criteria of acute rejection. For comparisons we used chi(2) and nonparametric Mann-Whitney test with a threshold of significance of p<0.05. ALLO rats lost more weight after SBTx than SYN rats (-13.02+/-4.39% vs. -8.04+/-5.08% of preoperative weight), although the difference was not significant (ns). A variable degree of graft rejection was histologically demonstrated in all ALLO rats, and DNA/protein content in the graft was significantly higher in this group (0.245+/-0.85 vs. 0.134+/-0.21, p<0.05). Gram-negative enteric bacteria were found in 4/5 ALLO and 4/6 SYN rats (ns), and aerobic Gram-positive bacteria in 2/5 and 3/6 (ns), respectively. Anaerobic growth occurred in mesenteric lymph nodes in one ALLO rat and in the bloodstream in another one. E. coli DNA was isolated in none of the ALLO but in two SYN rats (ns). BT was frequent after SBTx in both syngeneic and allogeneic strain combinations. Contrary to our expectations, BT after SBTx was not higher in ALLO group rats. However, anaerobic germs were isolated only in this group.

Acute Disease↗
PubMed2004

The vagus and recurrent laryngeal nerves in experimental congenital diaphragmatic hernia.

BACKGROUND: The etiology of the anatomic and functional abnormalities of the esophagus in infants surviving congenital diaphragmatic hernia (CDH) remains unclear. We showed previously that fetal rats with CDH have malformations of neural crest-derived structures. The aim of this study was to examine the anatomy of the vagus and the recurrent laryngeal nerves, both of neural crest origin, in rats with CDH. METHODS: We used the nitrofen-induced CDH fetal rat model. Nine control fetuses from four dams and nine fetuses with CDH from seven dams were included in this study. Embryos were fixed in formalin and a thoracic block from the larynx to tracheal bifurcation was serially sectioned in the horizontal plane. One in every ten sections was stained with hematoxylin and eosin. The image was digitalized using biological software (TDR-3dbase). Vagus and recurrent laryngeal nerves, trachea, esophagus and the great vessels were examined. In order to obtain the three-dimensional reconstructions, 90-120 consecutive images were used. RESULTS: In comparison with controls there were striking abnormalities of the vagus and the recurrent laryngeal nerves in fetuses with CDH: (1) absence of the left (2/9) or right (2/9) vagus nerves; (2) absence of the left (3/9) or right (3/9) recurrent laryngeal nerves; (3) marked hypoplasia of the trunk of the vagus (2/9); (4) deviations of their normal course and change of normal anatomical relationships into the mediastinum (2/9); and (5) abnormal branching of the lower portion of the vagus (1/9). CONCLUSIONS: Rat fetuses with CDH have anomalies of the vagus and recurrent laryngeal nerves that support the concept of a neural crest involvement in the origin of this malformation. 3-D reconstructions allow a detailed analysis and provide a precise insight into the real anatomy. These observations may explain esophageal motility disorders in CDH.

Animals↗
PubMed2002

Thermal treatment of the minority game.

We study a cost function for the aggregate behavior of all the agents involved in the minority game (MG) or the bar attendance model (BAM). The cost function allows us to define a deterministic, synchronous dynamic that yields results that have the main relevant features than those of the probabilistic, sequential dynamics used for the MG or the BAM. We define a temperature through a Langevin approach in terms of the fluctuations of the average attendance. We prove that the cost function is an extensive quantity that can play the role of an internal energy of the many-agent system while the temperature so defined is an intensive parameter. We compare the results of the thermal perturbation to the deterministic dynamics and prove that they agree with those obtained with the MG or BAM in the limit of very low temperature.

Journal Article↗
PubMed2002

Vascular endothelium express CS-1 fibronectin in allergic contact dermatitis.

BACKGROUND: Allergic contact dermatitis (ACD) is a common human dermatosis in which not all the mechanisms involved in its pathogenesis have been elucidated. OBJECTIVE: To study the expression of CS-1 fibronectin, TARC and Th1-associated chemokine receptors in biopsies from allergic patch test reactions. MATERIAL AND METHODS: Thirteen patients already diagnosed with ACD were challenged on the back with the antigen responsible of the disease and macroscopic responses and biopsies taken after 48 h. Skin biopsies from negative control challenge sites, AD and ICD were also taken. Samples were fixed, embedded in paraffin wax and processed in order to perform histological and immunohistochemical studies. RESULTS: All subjects with ACD showed a positive clinical response and a perivascular mononuclear cell infiltration at 48 h, which was not seen in the negative controls. The majority of skin-infiltrating cells were CD4+ and CD8+ and up to 54% or 40% of them expressed CXCR3 or CCR5, respectively. We also showed expression of CS-1 fibronectin in inflamed endothelial cells not only in ACD but also in AC and ICD. In contrast TARC was only expressed in ACD and AC. CONCLUSION: We showed for the first time that CS-1 fibronectin is expressed in dermal vessels from allergic patch tests positive reactions, as well as irritant and atopic skin lesions.

Adolescent↗
PubMed2001

Dynamical quenching and annealing in self-organization multiagent models.

We study the dynamics of a generalized minority game (GMG) and of the bar attendance model (BAM) in which a number of agents self-organize to match an attendance that is fixed externally as a control parameter. We compare the usual dynamics used for the minority game with one for the BAM that makes a better use of the available information. We study the asymptotic states reached in both frameworks. We show that states that can be assimilated to either thermodynamic equilibrium or quenched configurations can appear in both models, but with different settings. We discuss the relevance of the parameter G that measures the value of the prize for winning in units of the fine for losing. We also provide an annealing protocol by which the quenched configurations of the GMG can progressively be modified to reach an asymptotic equilibrium state that coincides with the one obtained with the BAM.

Journal Article↗
PubMed2001

Primary osteosarcoma of the uterine corpus: report of a case with immunohistochemical and ultrastructural study.

BACKGROUND: Primary uterine osteosarcoma is extremely rare, with only 15 cases reported in the literature. CASE: A 41-year-old woman presented with abnormal vaginal bleeding due to a large tumor arising from the uterine corpus. Histologically, the tumor showed the features of a malignant mesenchymal neoplasm with osteoid formation and lacked an epithelial component. Immunohistochemical and ultrastructural studies showed no evidence of epithelial differentiation. The tumor was excised and the patient received chemotherapy and radiation therapy postoperatively, but the tumor recurred locally at the 8-month follow-up. CONCLUSION: Osteosarcoma as a primary uterine tumor is exceedingly rare and should be distinguished from carcinosarcoma, which shows different macroscopic and histologic features. Prognosis of this neoplasm is very poor with an average life expectancy of 5 months.

Adult↗
PubMed2001

A comparison of 0.5% ropivacaine and 1% mepivacaine for sciatic nerve block in the popliteal fossa.

BACKGROUND: The purpose of this study was to compare anesthetic efficacy and postoperative analgesia of 0.5% ropivacaine and 1% mepivacaine for sciatic nerve block in the popliteal fossa (popliteal block). METHODS: A prospective, double-blind study was carried out in 58 adult patients scheduled for outpatient foot or ankle surgery. They were randomized to receive popliteal block with 40 ml of either 0.5% ropivacaine (group R) or 1% mepivacaine (group M). An atraumatic, Teflon-coated needle connected to a neurostimulator was used to make a single puncture using a posterior approach. The times to onset of sensory and motor block, and the need for intraoperative sedation were recorded. Before discharge, patients were asked to document the time to first analgesic use, time to return of full sensation in the foot, and their evaluation of the technique. RESULTS: Onset time (mean+/-standard deviation, 95% confidence interval) of both sensory block (6.5+/-5.1 min, 4.47-8.49, in group R and 6.2+/-3.7 min, 4.83-7.69, in group M) and motor block (6.6+/-4.4 min, 4.81-8.23, in group R and 7.9+/-4.1 min, 6.29-9.53, in group M) was similar in both groups. Postoperative analgesia lasted longer in group R (15.2+/-5.1 h, 13.25-17.21) than in group M (5.7+/-1.8 h, 5.01-6.41; P<0.001). Duration of sensory block was longer in group R (20.7+/-6.2 h, 18.51-23.01) than in group M (6.5+/-1.7 h, 5.86-7.16; P<0.001). Acceptance of the anesthetic procedure was similar in both groups. CONCLUSION: In this study we demonstrated that both 0.5% ropivacaine and 1% mepivacaine for popliteal block produced rapid, effective and safe anesthesia but postoperative analgesia was more long-lasting with ropivacaine.

Adult↗
PubMed2000

New superhard phases for three-dimensional C60-based fullerites

We have explored new possible phases of 3D C60-based fullerites using semiempirical potentials and ab initio density functional methods. We have found three closely related structures-two body-centered orthorhombic and one body-centered cubic-having 52, 56, and 60 tetracoordinated atoms per molecule. These 3D polymers result in semiconductors with bulk moduli near 300 GPa, and shear moduli around 240 GPa, which make them good candidates for new low density superhard materials.

Journal Article↗
PubMed1999

[Hospital organization of cardiopulmonary resuscitation].

That hospital cardiopulmonary resuscitation (CPR) should be supported by an organized plan rather than on the skills of individual health care personnel is a universally agreed-upon principle. Such a plan should guarantee that needed materials are available and in working order in all departments and that the team assigned to carry out CPR arrives promptly. Personnel other than the specialized team should also receive CPR training appropriate to their posts. The main features of a CPR plan are related to the five steps in the chain of survival: a) identification of a patient to be resuscitated, a matter that has important ethical ramifications; b) early recognition of cardiac arrest; c) early defibrillation; d) basic CPR, and e) advanced CPR. The CPR plan should incorporate the automatic recording of system, population, event and outcome variables. Task forces responsible for establishing and maintaining the plan and its quality control will periodically review the data with the aim of detecting errors, correcting them or introducing improvements. Various international societies and CPR committees have recently suggested a uniform way (the Utstein style) of recording and presenting data to allow comparisons either from hospital to hospital or over time within a single center.

Cardiopulmonary Resuscitation↗
PubMed1996

Solitary fibrous tumor of the mesentery.

We report a solitary fibrous tumor of the abdominal cavityt that presented as a encapsulated mass attached to the mesentery in a 33-yr-old man. Histologically, the lesion showed a disorganized arrangement of spindle cells in a collagenous background and prominent vascular channels of varying size. Tumor cells showed immunohistochemical reactivity for vimentin only. Cytokeratins and CD34 were negative. This report further extends the anatomic range of solitary fibrous tumor, a neoplasm that must be included in the differential diagnosis of well-defined abdominal masses. The behavior of this mesenteric solitary fibrous tumor has been benign.

Adult↗