Cellulose/Salep-based intelligent aerogel with red grape anthocyanins: Preparation, characterization and application in beef packaging.

The purpose of this study was to prepare a porous intelligent aerogel for food packaging applications, in particular for monitoring minced beef freshness, using cellulose extracted from grape stalk, Salep as a copolymer, and red grape anthocyanins as a pH-sensitive pigment. Aerogels based on cellulose 1% (w/v) and Salep 1% (w/v) at ratios of 1:3, 3:1, and 1:1 were prepared by lyophilization. Aerogel with high porosity, low density, and higher mean pore size was chosen for preparing intelligent colorimetric aerogel (ICA) with the addition of 0.44 mg/100 mL of anthocyanins. Based on the color parameters, the stability of ICA was satisfactory when exposed to both light and dark conditions, as well as when stored at either 4 or 25 °C. Additionally, X-ray diffraction and thermogravimetric analyses indicated that an amorphous aerogel was formed, with a thermal decomposition temperature of 320 °C. The color of the ICA changed from purple on the first and 3rd days of packaging to blue-gray on the 6th day. As the spoilage process continued, the color of the indicator became dark brown. Taken together, ICA showed a quick response to minced beef spoilage with the ability to differentiate between fresh and spoiled meat during storage at 4 °C.

Extracellular Volume Fraction by Computed Tomography Predicts Long-Term Prognosis Among Patients With Cardiac Amyloidosis.

BACKGROUND: Light chain (AL) and transthyretin (ATTR) amyloid fibrils are deposited in the extracellular space of the myocardium, resulting in heart failure and premature mortality. Extracellular expansion can be quantified by computed tomography, offering a rapid, cheaper, and more practical alternative to cardiac magnetic resonance, especially among patients with cardiac devices or on renal dialysis. OBJECTIVES: This study sought to investigate the association of extracellular volume fraction by computed tomography (ECVCT), myocardial remodeling, and mortality in patients with systemic amyloidosis. METHODS: Patients with confirmed systemic amyloidosis and varying degrees of cardiac involvement underwent electrocardiography-gated cardiac computed tomography. Whole heart and septal ECVCT was analyzed. All patients also underwent clinical assessment, electrocardiography, echocardiography, serum amyloid protein component, and/or technetium-99m (99mTc) 3,3-diphosphono-1,2-propanodicarboxylic acid scintigraphy. ECVCT was compared across different extents of cardiac infiltration (ATTR Perugini grade/AL Mayo stage) and evaluated for its association with myocardial remodeling and all-cause mortality. RESULTS: A total of 72 patients were studied (AL: n = 35, ATTR: n = 37; median age: 67 [IQR: 59-76] years, 70.8% male). Mean septal ECVCT was 42.7% ± 13.1% and 55.8% ± 10.9% in AL and ATTR amyloidosis, respectively, and correlated with indexed left ventricular mass (r = 0.426; P < 0.001), left ventricular ejection fraction (r = 0.460; P < 0.001), N-terminal pro-B-type natriuretic peptide (r = 0.563; P < 0.001), and high-sensitivity troponin T (r = 0.546; P < 0.001). ECVCT increased with cardiac amyloid involvement in both AL and ATTR amyloid. Over a mean follow-up of 5.3 ± 2.4 years, 40 deaths occurred (AL: n = 14 [35.0%]; ATTR: n = 26 [65.0%]). Septal ECVCT was independently associated with all-cause mortality in ATTR (not AL) amyloid after adjustment for age and septal wall thickness (HR: 1.046; 95% CI: 1.003-1.090; P = 0.037). CONCLUSIONS: Cardiac amyloid burden quantified by ECVCT is associated with adverse cardiac remodeling as well as all-cause mortality among ATTR amyloid patients. ECVCT may address the need for better identification and risk stratification of amyloid patients, using a widely accessible imaging modality.

Alginate-amphotericin B nanocomplexes covered by nanocrystals from bacterial cellulose: physico-chemical characterization and in vitro toxicity.

Nanocomplexes systems made up natural poylymers have pharmacotechnical advantages such as increase of water solubility and a decrease of drugs toxicity. Amphotericin B (AmB) is a drug apply as anti-leishmanial and anti-fungal, however it has low water solubility and high toxicity, limiting its therapeutic application. With this in mind, the present study aimed to produce nanocomplexes composed by alginate (Alg), a natural polymer, with AmB covered by nanocrystals from bacterial cellulose (CNC). For this reason, the nanocomplexes were produced utilizing sodium alginate, amphotericin B in a borate buffer (pH 11.0). The CNC was obtained by enzymatic hydrolysis of the bacterial cellulose. To CNC cover the nanocomplexes 1 ml of the nanocomplexes was added into 1 ml of 0.01% CNC suspension. The results showed an ionic adsorption of the CNC into the Alg-AmB nanocomplexes surface. This phenomena was confirmed by an increase in the particle size and PDI decrease. Besides, nanocomplexes samples covered by CNC showed uniformity. The amorphous inclusion of AmB complex into the polysaccharide chain network in both formulations. AmB in the nanocomplexes was in supper-aggregated form and showed good biocompatibility, being significantly less cytotoxic in vitro against kidney cells and significantly less hemolytic compared to the free-drug. The in vitro toxicity results indicated the Alg-AmB nanocomplexes can be considered a non-toxic alternative to improve the AmB therapeutic effect. All process to obtain nanocomplexes and it coat was conduce without organic solvents, can be considered a green process, and allowed to obtain water soluble particles. Furthermore, CNC covering the nanocomplexes brought additional protection to the system can contribut advancement in the pharmaceutical.

The Reality of Critical Cancer Patients in a Polyvalent Intensive Care Unit.

Background and objective With the increasing incidence of cancer and the rise in the survival rates of cancer patients, more and more oncological candidates are being considered for admission to intensive care units (ICU). Several studies have demonstrated no difference in the outcomes of cancer patients compared to non-cancer patients. Our study aimed to describe and analyze the outcomes related to cancer patients in a polyvalent ICU. Methods We conducted a retrospective study of consecutive oncological patients admitted to a polyvalent ICU (2013-2017). Cox model and receiver operating characteristic (ROC) curve analysis were performed to analyze the results. Results A total of 236 patients were included in the study; the mean age of the patients was 53.5 ± 15.3 years, and 65% of them were male. The main cancer types were those related to the central nervous system (CNS; 31%), as well as gastrointestinal (18%), genitourinary (17%), and hematological (15%). Curative/diagnostic surgeries (49%) and sepsis/septic shock (17%) were the main reasons for admission. The Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) scores in hematological patients vs. solid tumors were as follows: 30 vs. 20 and 63 vs. 38, respectively (p<0.005). Vasopressors, invasive mechanical ventilation (IMV), and renal replacement therapy (RRT) were used more widely in hematological patients compared to solid-tumor patients. Length of stay was longer in hematological patients vs. solid-tumor patients (12.8 vs. 7 days, p=0.002). The median overall survival in hematological patients was one month and that in solid-tumor patients was 5.8 months (p<0.005). The survival rate at six months was better than described in the existing literature (48 vs. 32.4%). Conclusion Both SAPS II and APACHE II scores were reasonably accurate in predicting mortality, demonstrating their value in cancer patients.

Coronary Artery Bypass Grafting Versus Percutaneous Coronary Intervention in Patients With Non-ST-Elevation Myocardial Infarction and Left Main or Multivessel Coronary Disease.

Current recommendations on the optimal revascularization strategy in Non-ST-elevation myocardial infarction (NSTEMI) with left main (LM) or multivessel coronary disease (MVD) are based upon randomized clinical trials conducted in stable coronary artery disease. In a real-world contemporary observational registry, we compared the long-term outcome of NSTEMI patients with LM/MVD (n = 1,104) submitted to coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or optimized medical therapy (OMT). The primary end point was 5-year all-cause mortality. Results were assessed in the entire population (CABG 289, PCI 399, and OMT 416) and in a propensity score-matched cohort of CABG (n = 159) and PCI (n = 159). Crude 5-year mortality rates in CABG and PCI were 25.3% versus 29.6%, respectively (unadjusted hazard ratio [HR] 1.2; 95% confidence intervals [CI] 0.9 to 1.6; p = 0.212); OMT, however, was associated with a twofold higher risk of mortality when compared with any revascularization strategy (unadjusted HR 2.0; 95% CI 1.7 to 2.5; p < 0.001). After propensity score-matching and multivariate analysis, there was a trend toward a higher incidence of the primary end point in patients who underwent PCI versus CABG (31% vs 21%; adjusted HR 1.52; 95% CI 0.93 to 2.50; p = 0.094). This was a consistent finding over subgroups deemed clinically relevant, such as in patients with LM or proximal left anterior descending disease, SYNergy between percutaneous coronary intervention with TAXus ≥23 and left ventricle ejection fraction <40%. In conclusion, in a real-world cohort of NSTEMI patients with LM/MVD, those selected for OMT had a dire outcome. Although adjusted 5-year mortality was statistically similar between revascularization strategies, there was a trend favoring CABG, which might be the preferred option in LM, proximal LAD, SYNergy between percutaneous coronary intervention with TAXus ≥23, and left ventricle ejection fraction <40% subgroups.

Inflammatory response to dextrin-based hydrogel associated with human mesenchymal stem cells, urinary bladder matrix and Bonelike® granules in rat subcutaneous implants.

Increasing relevance has been attributed to hydrogels due to their ability to provide an extracellular matrix (ECM)-like environment for cellular adhesion and proliferation, acting as mechanical scaffolds for tissue remodeling or as delivery matrices. In vivo biocompatibility of a hybrid dextrin hydrogel produced from oxidized dextrin and adipic acid dihydrazide and its combinations with human mesenchymal stem cells (hMSCs), ECM from a porcine bladder (urinary bladder matrix) and ceramic granules (Bonelike®), was evaluated following ISO 10993 after subcutaneous implantation in a rat model. Histological analysis after 3 and 15 d showed typical acute and chronic inflammatory responses, respectively, with a more severe reaction exhibited whenever the ceramic granules were present. However, the dextrin hydrogel was able to stabilize granules in the implant site. Dextrin hydrogel was scored as slight irritant after 3 d, similar to its combination with UBM, and as non-irritant after 15 d. The presence of viable hMSCs in the subcutaneous tissue could be confirmed by the presence of anti-human nuclei antibody (HuNu+) cells. The production of growth factors and inflammatory and immunomodulatory cytokines by these cells was also quantified in peripheral blood confirming the successful encapsulation of hMSCs into the hydrogel matrix for cell survival promotion. The presence of hMSCs seemed to modulate the inflammatory response by accelerating its progression when compared to the acellular experimental groups. Dextrin hydrogel has proven to be a biocompatible multifunctional matrix for minimally invasive biomedical procedures, including orthopedic surgeries when associated with bone substitutes and also as a possible encapsulation matrix for cell-based therapies.

Mechanical fatigue performance of PCL-chondroprogenitor constructs after cell culture under bioreactor mechanical stimulus.

In tissue engineering of cartilage, polymeric scaffolds are implanted in the damaged tissue and subjected to repeated compression loading cycles. The possibility of failure due to mechanical fatigue has not been properly addressed in these scaffolds. Nevertheless, the macroporous scaffold is susceptible to failure after repeated loading-unloading cycles. This is related to inherent discontinuities in the material due to the micropore structure of the macro-pore walls that act as stress concentration points. In this work, chondrogenic precursor cells have been seeded in poly-ε-caprolactone (PCL) scaffolds with fibrin and some were submitted to free swelling culture and others to cyclic loading in a bioreactor. After cell culture, all the samples were analyzed for fatigue behavior under repeated loading-unloading cycles. Moreover, some components of the extracellular matrix (ECM) were identified. No differences were observed between samples undergoing free swelling or bioreactor loading conditions, neither respect to matrix components nor to mechanical performance to fatigue. The ECM did not achieve the desired preponderance of collagen type II over collagen type I which is considered the main characteristic of hyaline cartilage ECM. However, prediction in PCL with ECM constructs was possible up to 600 cycles, an enhanced performance when compared to previous works. PCL after cell culture presents an improved fatigue resistance, despite the fact that the measured elastic modulus at the first cycle was similar to PCL with poly(vinyl alcohol) samples. This finding suggests that fatigue analysis in tissue engineering constructs can provide additional information missed with traditional mechanical measurements.

Biocompatibility of a self-assembled glycol chitosan nanogel.

The research of chitosan-based nanogel for biomedical applications has grown exponentially in the last years; however, its biocompatibility is still insufficiently reported. Hence, the present work provides a thorough study of the biocompatibility of a glycol chitosan (GC) nanogel. The obtained results showed that GC nanogel induced slight decrease on metabolic activity of RAW, 3T3 and HMEC cell cultures, although no effect on cell membrane integrity was verified. The nanogel does not promote cell death by apoptosis and/or necrosis, exception made for the HMEC cell line challenged with the higher GC nanogel concentration. Cell cycle arrest on G1 phase was observed only in the case of RAW cells. Remarkably, the nanogel is poorly internalized by bone marrow derived macrophages and does not trigger the activation of the complement system. GC nanogel blood compatibility was confirmed through haemolysis and whole blood clotting time assays. Overall, the results demonstrated the safety of the use of the GC nanogel as drug delivery system.

Antiproliferative activity of fucan nanogel.

Sulfated fucans comprise families of polydisperse natural polysaccharides based on sulfated L-fucose. Our aim was to investigate whether fucan nanogel induces cell-specific responses. To that end, a non toxic fucan extracted from Spatoglossum schröederi was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution with hydrophobic chains was close to 100%, as estimated by elemental analysis. SNFfuc in aqueous media had a mean diameter of 123 nm and zeta potential of -38.3 ± 0.74 mV, as measured by dynamic light scattering. Nanoparticles conserved their size for up to 70 days. SNFuc cytotoxicity was determined using the MTT assay after culturing different cell lines for 24 h. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0%-43.7% at nanogel concentrations of 0.05-0.5 mg/mL and rabbit aorta endothelial cells (RAEC) non-tumor cell line proliferation displayed inhibition of 8.0%-22.0%. On the other hand, nanogel improved Chinese hamster ovary (CHO) and monocyte macrophage cell (RAW) non-tumor cell line proliferation in the same concentration range. The antiproliferative effect against tumor cells was also confirmed using the BrdU test. Flow cytometric analysis revealed that the fucan nanogel inhibited 786 cell proliferation through caspase and caspase-independent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle.

Unraveling the uptake mechanisms of mannan nanogel in bone-marrow-derived macrophages.

The mechanisms associated with the cellular internalization of nanomedicines must be carefully considered when designing drug- and vaccine-delivery systems. The cellular fate and effects of nanomedicines depend to a large extent on the cell uptake routes. A self-assembled mannan nanogel is developed as a vaccination platform for antigen and adjuvant delivery. The mannan nanogel uptake by murine bone-marrow-derived macrophages is found to be time-, concentration-, and energy-dependent, involving mannose-receptor-mediated phagocytosis and clathrin-mediated endocytosis. The nanogel is also visualized in the cytosol suggesting endolysosomal escape. These results indicate that mannan nanogel is a promising versatile carrier for intracellular delivery of vaccines or therapeutic agents.

Self-assembled mannan nanogel: cytocompatibility and cell localization.

Amphiphilic mannan, produced by the Michael addition of hydrophobic 1-hexadecanethiol to vinyl methacrylated mannan, self-assembles in aqueous medium through hydrophobic interactions among alkyl chains. Resultant nanogel is stable, spherical, polydisperse, with 50-140 nm mean hydrodynamic diameter depending on the polymer degree of substitution, and nearly neutral negative surface charge. No cytotoxicity of mannan nanogel is detected up to about 0.4 mg/mL in mouse embryo fibroblast cell line 3T3 and mouse bone marrow-derived macrophages (BMDM) using cell proliferation, lactate dehydrogenase and Live/Dead assays. Comet assay, under the tested conditions, reveals no DNA damage in fibroblasts but possible in BMDM. BMDM internalize the mannan nanogel, which is observed in vesicles in the cytoplasm by confocal laser scanning microscopy. Confocal colocalization image analysis denotes that the entrance and exit of nanogel and FM 4-64 might occur by the same processes--endocytosis and exocytosis--in BMDM. Physicochemical characteristics, in vitro cytocompatibility and uptake of self-assembled mannan nanogel by mouse BMDM are great signals of the potential applicability of this nanosystem for macrophages targeted delivery of vaccines or drugs, acting as potential nanomedicines, always with the key goal of preventing and/or treating diseases.

Biocompatibility of mannan nanogel--safe interaction with plasma proteins.

BACKGROUND: Self-assembled mannan nanogels are designed to provide a therapeutic or vaccine delivery platform based on the bioactive properties of mannan to target mannose receptor expressed on the surface of antigen-presenting cells, combined with the performance of nanogels as carriers of biologically active agents. METHODS: Proteins in the corona around mannan nanogel formed in human plasma were identified by mass spectrometry after size exclusion chromatography or centrifugation followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Structural changes and time dependent binding of human apolipoprotein A-I (apoA-I) and human serum albumin (HSA) to mannan nanogel were studied using intrinsic tryptophan fluorescence and circular dichroism spectroscopy. The mannan nanogel effect on blood coagulation and fibrillation of Alzheimer's disease-associated amyloid ß peptide and hemodialysis-associated amyloidosis ß2 microglobulin was evaluated using thrombin generation assay or thioflavin T fluorescence assay, respectively. RESULTS: The protein corona around mannan nanogel is formed through a slow process, is quite specific comprising apolipoproteins B-100, A-I and E and HSA, evolves over time, and the equilibrium is reached after hours to days. Structural changes and time dependent binding of apoA-I and HSA to mannan nanogel are minor. The mannan nanogel does not affect blood coagulation and retards the fibril formation. CONCLUSIONS: Mannan nanogel has a high biosafety and biocompatibility, which is mandatory for nanomaterials to be used in biomedical applications. GENERAL SIGNIFICANCE: Our research provides a molecular approach to evaluate the safety aspects of nanomaterials, which is of general concern in society and science.

Supramolecular assembled nanogel made of mannan.

The supramolecular assembly of amphiphilic mannan, synthesized by the Michael addition of hydrophobic 1-hexadecanethiol to vinyl methacrylated mannan, originates in aqueous medium the formation of a nanogel, stabilized by hydrophobic interactions among alkyl chains. The critical aggregation concentration, calculated by fluorescence spectroscopy ranged between 0.002 and 0.01 mg/mL, depending on the polymer degree of substitution. The cryo-field emission scanning electron microscopy showed spherical macromolecular micelles with diameters between 100 and 500 nm. The dynamic light scattering analysis revealed a polydisperse colloidal system, with mean hydrodynamic diameter between 50 and 140 nm, depending on the polymer degree of substitution. The nanogel is negatively charged, stable over a 6 months storage period, and stable at pH 3-8, salt or urea solutions. Bovine serum albumin and curcumin were spontaneously incorporated in the nanogel, being stabilized by the hydrophobic domains, opening the possibility for future applications as potential delivery systems for therapeutic molecules. In vitro assays were carried out to characterize the biocompatibility of the nanogel. A toxic effect of mannan-C(16) was observed, specific to mouse macrophage-like cell line J774, not affecting mouse embryo fibroblast cell line 3T3 viability.

[Determination of creatinine in drained liquid. Urinary leak or lymphocele?]. / Diagnóstico de colecciones líquidas postrasplante renal. ¿Fuga urinaria o linfocele?

BACKGROUND: Liquid collections around the renal graft that are displayed in 51% of cases implicate a diagnostic challenge and a risk for graft function. We undertook this study to determine the usefulness of creatinine concentration measurement in drainage in patients with renal transplantation. METHODS: We selected patients with surgically corrected urinary leak and patients with lymphocele from November 1, 1999, to November 30, 2008, in whom we determined the creatinine concentration in liquid drainage, plasma and urine. RESULTS: We included five patients with urinary leak and six patients with lymphocele. Two patients had urinary leak before the lymphocele. The t value of the plasma creatinine (Pcreat), drainage (Dcreat) and urine (Ucreat) was 0.89, 0.045 and 0.63, respectively. The diagnostic criteria of urinary leak represented a value between the creatinine of the drainage and plasma (D/Pcreat) >6, between urine and drainage (U/Dcreat) <3 and between urine and plasma (U/ Pcreat) <7. When we compared both groups the χ(2) values were 0.018, 0.007 and 0.094, respectively. CONCLUSIONS: There is a statistically significant difference among the creatinine drainage liquid values. Our study shows that D/Pcreat ratio >6 after the first week or U/Dcreat ratio <3 at any time during the postoperative period represents a six-times higher possibility of urinary leak.

Desensitization and renal transplant: plasmapheresis/IVIG standard dose in patients with high immunological risk.

BACKGROUND: Patients with high immunological risk have been relegated to the growing waiting list for an immunologically compatible donor. Our objective was to report the experience of a transplant center in desensitization of patients with high immunological risk. METHODS: We carried out a descriptive and retrospective study. Included were all the renal transplant patients from November 1999 to January 2008 in which we used plasmapheresis and standard dose of intravenous immunoglobulin (IVIG) as desensitization. RESULTS: Eight patients had history of alloimmunity (positive crossmatch or high panel-reactive antibodies (PRA >30%). Desensitization was accomplished with plasmapheresis and exchange of 1.5 plasma volume. Subsequent to each session we administered a standard dose of IVIG (5 g/dose). Immunosuppression began equal to the first plasmapheresis with calcineurin inhibitor (tacrolimus) plus six patients with mycophenolate mofetil and two patients with sirolimus. In seven cases, negative crossmatches were obtained before the transplantation, except in the eighth case in whom it was not done. Two patients received human antibodies against CD25 (basiliximab, 20 mg/dose). During their evolution, all patients maintained stable graft function. CONCLUSIONS: According to our experience, renal graft outcome in patients with high immunological risk after an adequate desensitization protocol is similar to that observed in nonsensitized patients, at least during the first year of transplantation.

Desensibilización y trasplante renal: plasmaféresis-IVIG a dosis estándar en pacientes con alto riesgo inmunológico / Desensitization and renal transplant: plasmapheresis/IVIG standard dose in patients with high immunological risk

Introducción: Los pacientes con alto riesgo inmunológico siguen siendo relegados a la cada vez más larga lista de espera de un donador inmunológicamente compatible. El objetivo de esta comunicación es informar la experiencia de un centro de trasplantes en la desensibilización de pacientes con alto riesgo inmunológico. Material y métodos: Estudio descriptivo y retrospectivo de todos los pacientes sometidos a trasplante renal de noviembre de 1999 a enero de 2008, en quienes se llevó a cabo desensibilización pretrasplante renal. Resultados: Ocho pacientes presentaron aloinmunización (pruebas cruzadas positivas o panel reactivo de anticuerpos alto, PRA > 30 %). La desensibilización se realizó mediante sesiones de plasmaféresis con recambio de 1.5 volúmenes plasmáticos, y posterior a cada una se administró una dosis estándar de inmunoglubulina intravenosa (IVIG 5 g/dosis). La inmunosupresión se inició en la primera sesión de plasmaféresis con base en un inhibidor de calcineurinas (tacrolimus); en seis pacientes se añadió mofetil micofenolato y en dos, sirolimus. En siete se obtuvieron pruebas cruzadas negativas con el donador previo al trasplante; en el octavo no se efectuaron. En dos se administró anticuerpos humanizados contra CD25 (20 mg/dosis de basiliximab). Todos los pacientes han mantenido función estable del injerto. Conclusiones: De acuerdo con nuestra experiencia, la sobrevida del injerto renal en pacientes con alto riesgo inmunológico posterior a un adecuado protocolo de desensibilización y estrecha vigilancia postrasplante es similar a la observada en pacientes no sensibilizados, al menos durante el primer año del trasplante.

BACKGROUND: Patients with high immunological risk have been relegated to the growing waiting list for an immunologically compatible donor. Our objective was to report the experience of a transplant center in desensitization of patients with high immunological risk. METHODS: We carried out a descriptive and retrospective study. Included were all the renal transplant patients from November 1999 to January 2008 in which we used plasmapheresis and standard dose of intravenous immunoglobulin (IVIG) as desensitization. RESULTS: Eight patients had history of alloimmunity (positive crossmatch or high panel-reactive antibodies (PRA >30%). Desensitization was accomplished with plasmapheresis and exchange of 1.5 plasma volume. Subsequent to each session we administered a standard dose of IVIG (5 g/dose). Immunosuppression began equal to the first plasmapheresis with calcineurin inhibitor (tacrolimus) plus six patients with mycophenolate mofetil and two patients with sirolimus. In seven cases, negative crossmatches were obtained before the transplantation, except in the eighth case in whom it was not done. Two patients received human antibodies against CD25 (basiliximab, 20 mg/dose). During their evolution, all patients maintained stable graft function. CONCLUSIONS: According to our experience, renal graft outcome in patients with high immunological risk after an adequate desensitization protocol is similar to that observed in nonsensitized patients, at least during the first year of transplantation.

Endoscopia en cirugía bariátrica: un nuevo reto? / Endoscopy and bariatric surgery: a new challenge?

BACKGROUND: Obesity in Mexico appears with a frequency of 38.4% in men and 43.3% in women. Within the therapeutic options, bariatric surgery is defined as the only effective treatment in the long term, and the number of procedures is increasing. Postoperative complications are sometimes challenging for those who are evaluating them. We undertook this study to describe and to correlate endoscopic findings with gastrointestinal symptoms in patients who have undergone a bariatric procedure. METHODS: This was a descriptive, prospective and longitudinal study that included all patients who underwent bariatric surgery between January 2004 and October 2006 and who presented gastrointestinal symptoms requiring postoperative endoscopic evaluation. RESULTS: Thirty-six patients were subjected to 45 videoendoscopies between January 2004 and October 2006. The most frequent endoscopic findings were normal postsurgical anatomy (18 patients, 50%), marginal ulcer (5 patients, 13.8%), stomal stenosis (8 patients, 22.2%), and migration of gastric band (1 patient, 2.7%). Abdominal pain was the most frequent symptom, appearing in 58.3% of patients, mainly in those with normal endoscopy. Nausea and vomiting were reported in 55.5% of the cases; 25% of the procedures done in the first 6 months were normal as compared with 75% of the cases that were done after 6 months. CONCLUSIONS: Normal videoendoscopy was the most frequent finding among patients who had undergone a bariatric procedure. Stomal stenosis was the most frequent abnormality. The presence of abdominal pain beginning 6 months postoperatively is a characteristic that predicts normal videoendoscopy.

[Endoscopy and bariatric surgery. A new challenge?]. / Endoscopia en cirugía bariátrica. Un nuevo reto?

BACKGROUND: Obesity in Mexico appears with a frequency of 38.4% in men and 43.3% in women. Within the therapeutic options, bariatric surgery is defined as the only effective treatment in the long term, and the number of procedures is increasing. Postoperative complications are sometimes challenging for those who are evaluating them. We undertook this study to describe and to correlate endoscopic findings with gastrointestinal symptoms in patients who have undergone a bariatric procedure. METHODS: This was a descriptive, prospective and longitudinal study that included all patients who underwent bariatric surgery between January 2004 and October 2006 and who presented gastrointestinal symptoms requiring postoperative endoscopic evaluation. RESULTS: Thirty-six patients were subjected to 45 videoendoscopies between January 2004 and October 2006. The most frequent endoscopic findings were normal postsurgical anatomy (18 patients, 50%), marginal ulcer (5 patients, 13.8%), stomal stenosis (8 patients, 22.2%), and migration of gastric band (1 patient, 2.7%). Abdominal pain was the most frequent symptom, appearing in 58.3% of patients, mainly in those with normal endoscopy. Nausea and vomiting were reported in 55.5% of the cases; 25% of the procedures done in the first 6 months were normal as compared with 75% of the cases that were done after 6 months. CONCLUSIONS: Normal videoendoscopy was the most frequent finding among patients who had undergone a bariatric procedure. Stomal stenosis was the most frequent abnormality. The presence of abdominal pain beginning 6 months postoperatively is a characteristic that predicts normal videoendoscopy.

[Biosimulator training and its impact on skill in laparoscopic cholecystectomy]. / Entrenamiento en un biosimulador y su impacto sobre la destreza en colecistectomía laparoscópica.

OBJECTIVE: We undertook this study to determinate the educational impact of training in an inanimate biosimulator in terms of effectiveness, time and complications in performing laparoscopic cholecystectomy. METHODS: We used a comparative, experimental cohort, prospective and longitudinal. Three first-postgraduate-year residents and one pre-grade internship physician were trained and assessed in basic laparoscopic skills using a biosimulator (fiberglass "dummy" where animal organs are introduced ex-vivo). The participants acted as their own control, performing a procedure to determine surgical time, complications and effectiveness. Later they observed a short video demonstrating the suitable development of laparoscopic cholecystectomy. The video defined the specific deviations from the ideal cholecystectomy, which were considered as errors. Every procedure was videotaped, beginning with the careful dissection of cystic structures and clipping them, continuing with the dissection of the gallbladder from the liver with the standardized method. Each participant performed ten procedures. RESULTS: There were no differences in baseline assessment of basic skills. All participants completed all proposed procedures. Surgical time was 61% faster at the end of the study (p<0.001), as well as demonstrating a lower rate of complications of 0.67% (p<0.009). CONCLUSIONS: Skills training in endoscopic surgery by means of an inanimate biosimulator is superior to traditional training because it decreases surgical time and surgical complications without ethical considerations and the effect of a learning curve in the operating room.

Entrenamiento en un biosimulador y su impacto sobre la destreza en colecistectomía laparoscópica / Biosimulator training and its impact on skill in laparoscopic cholecystectomy

Objetivo: determinar el impacto educacional del entrenamiento en un biosimulador inanimado en términos de efectividad, tiempo y complicaciones, respecto a la colecistectomía laparoscópica. Material y métodos: estudio comparativo, experimental de una cohorte, prospectivo y longitudinal. Tres médicos residentes de primer año de cirugía y un interno de pregrado, fueron entrenados y evaluados en habilidades laparoscópicas elementales mediante el empleo de un biosimulador (maniquí de fibra de vidrio en el que se introducen órganos de animales ex vivo). Los sujetos fueron su propio control: realizaron un procedimiento inicial en el que se determinó tiempo quirúrgico, complicaciones y efectividad. Posteriormente observaron un corto video que mostraba el desarrollo idóneo de la colecistectomía, y en el que se identificaban las desviaciones específicas del desempeño adecuado. Posteriormente cada sujeto realizó 10 procedimientos. Resultados: no existieron diferencias en la evaluación inicial de habilidades elementales. Los individuos completaron todos los procedimientos propuestos. Las disecciones de las estructuras císticas y de la vesícula biliar fueron 61 % más rápidas al finalizar el estudio (p < 0.001); la tasa de complicación fue de 0.67 % (p <0.009). Conclusión: el entrenamiento de habilidades en cirugía endoscópica por medio de un biosimulador inanimado es mejor que el entrenamiento tradicional, ya que disminuye el tiempo quirúrgico y las complicaciones en la sala de operaciones.

OBJECTIVE: We undertook this study to determinate the educational impact of training in an inanimate biosimulator in terms of effectiveness, time and complications in performing laparoscopic cholecystectomy. METHODS: We used a comparative, experimental cohort, prospective and longitudinal. Three first-postgraduate-year residents and one pre-grade internship physician were trained and assessed in basic laparoscopic skills using a biosimulator (fiberglass [quot ]dummy[quot ] where animal organs are introduced ex-vivo). The participants acted as their own control, performing a procedure to determine surgical time, complications and effectiveness. Later they observed a short video demonstrating the suitable development of laparoscopic cholecystectomy. The video defined the specific deviations from the ideal cholecystectomy, which were considered as errors. Every procedure was videotaped, beginning with the careful dissection of cystic structures and clipping them, continuing with the dissection of the gallbladder from the liver with the standardized method. Each participant performed ten procedures. RESULTS: There were no differences in baseline assessment of basic skills. All participants completed all proposed procedures. Surgical time was 61% faster at the end of the study (p<0.001), as well as demonstrating a lower rate of complications of 0.67% (p<0.009). CONCLUSIONS: Skills training in endoscopic surgery by means of an inanimate biosimulator is superior to traditional training because it decreases surgical time and surgical complications without ethical considerations and the effect of a learning curve in the operating room.