Clinical outcomes and complications of single anastomosis duodenal-ileal bypass with sleeve gastrectomy: A 2-year follow-up study in Bogotá, Colombia.

BACKGROUND: The global prevalence of obesity has increased over the past 40 years, and bariatric surgery has proven to be the most effective therapy for long-term weight loss. Its principles are based on modifying the brain-gut axis by altering the gastrointestinal anatomy and affecting the function of gastrointestinal hormones, thereby modifying satiety signals. Single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) combines both techniques and has become an alternative to gastric bypass and biliopancreatic diversion procedures for treating severe obesity and associated metabolic diseases in selected patients. AIM: To describe the outcomes and complications of SADI-S. METHODS: We retrospectively analyzed the data of patients who underwent SADI-S laparoscopically at the Clínica Reina Sofía in Bogotá, Colombia. This study assessed the therapeutic effectiveness of SADI-S in terms of short-term preoperative clinical characteristics, postoperative complications, comorbidities, nutritional defi-ciencies, and intraoperative complications during a 2-year follow-up. RESULTS: Sixty-one patients with a mean body mass index (BMI) of 50 ± 7.1 kg/m2 underwent laparoscopic SADI-S. The mean operative time and hospital stays were 143.8 ± 42 min and 2.3 ± 0.8 d, respectively. The mean follow-up period was 18 mo, and the mean BMI decreased to 28.5 ± 12.2 kg/m2. The excess BMI loss was 41.8% ± 13.5%, and the weight loss percentage was 81.1% ± 17.0%. Resolution of obesity-related comorbidities, including type 2 diabetes mellitus, hypertension, dyslipidemia, and obstructive sleep apnea, was achieved and defined as complete or partial remission. No intraoperative complications were observed. Short-term complications were observed in four (6.8%) patients. However, larger studies with longer follow-up periods are required to draw definitive conclusions. CONCLUSION: SADI-S has a low intraoperative and postoperative complication rate and is effective for weight loss and improving obesity-related comorbidities, including hypertension, type 2 diabetes mellitus, dyslipidemia, and sleep apnea syndrome.

Endovascular treatment simulations using a novel in vitro brain arteriovenous malformation model based on three-dimensional printing millifluidic technology.

BACKGROUND: Brain arteriovenous malformations (bAVM) are complex vascular diseases. Several models have been used to simulate endovascular treatments; thus in vitro models have not been widely employed because it has been difficult to recreate realistic phantoms of this disease. OBJECTIVE: To describe the development and evaluate the preliminary experience of a novel bAVM in vitro model for endovascular embolization using millifluidic three-dimensional (3D) printing technology. METHODS: We designed a bAVM phantom starting from simple to more complex designs, composed of a nidus, feeding arteries and draining vein. We recreate the design by using millifluidic technology with stereolithography 3D printing. Structural and functional tests were performed using angiographic images and computer flow dynamics. Treatment simulations with ethylene vinyl alcohol were tested using two different microcatheter position techniques. A Likert-scale questionnaire was applied to perform a qualitative evaluation of the model. RESULTS: We developed a realistic model of a bAVM with hollow channels. The structural evaluation showed a high precision of the 3D printing process. Embolization tests with the liquid agent gave similar sensations and material behaviour as in vivo cases. There were no significant differences between microcatheter position techniques, thus we observed a trend for better nidus filling with a deeper in-nidus position technique. CONCLUSIONS: We were able to create and test a novel bAVM in vitro model with stereolithography 3D printing in resin. It showed a high capacity for simulating endovascular embolization characteristics, with an excellent user experience. It could be potentially used for training and testing of bAVM embolizations.

Modeling the COVID-19 Travel Choices in Colombia and India: A Hybrid Multiple Discrete-Continuous Nested Extreme Value Approach.

The COVID-19 pandemic has affected many daily activities, primarily as a result of the perceived contagion risk and government restrictions to mitigate the spread of the virus. To this end, drastic changes in the trip choices for commuting to work have been reported and studied, mostly through descriptive analysis. On the other hand, modeling-based research that can simultaneously understand both changes in mode choice and its frequency at an individual level has not been much used in existing studies. As such, this study aims to understand the changes in mode-choice preference and the frequency of trips, comparing pre-COVID with during-COVID scenarios, in two different countries of the Global South: Colombia and India. A hybrid multiple discrete-continuous nested extreme value model was implemented using the data obtained from online surveys in Colombia and India during the early COVID-19 period of March and April 2020. This study found that, in both countries, utility related to active modes (more used) and public transportation (less used) changed during the pandemic. In addition, this study highlights potential risks in likely unsustainable futures where there may be increased use of private vehicles such as cars and motorcycles, in both countries. It was also identified that perceptions toward government responses had a significant impact on the choices in Colombia, though this was not the case in India. These results may help decision makers focus on public policies to encourage sustainable transportation by avoiding the detrimental long-term behavioral changes resulting from the COVID-19 pandemic.

Early Leukocyte Responses in Ex-Vivo Models of Healing and Non-Healing Human Leishmania (Viannia) panamensis Infections.

Early host-pathogen interactions drive the host response and shape the outcome of natural infections caused by intracellular microorganisms. These interactions involve a number of immune and non-immune cells and tissues, along with an assortment of host and pathogen-derived molecules. Our current knowledge has been predominantly derived from research on the relationships between the pathogens and the invaded host cell(s), limiting our understanding of how microbes elicit and modulate immunological responses at the organismal level. In this study, we explored the early host determinants of healing and non-healing responses in human cutaneous leishmaniasis (CL) caused by Leishmania (Viannia) panamensis. We performed a comparative transcriptomic profiling of peripheral blood mononuclear cells from healthy donors (PBMCs, n=3) exposed to promastigotes isolated from patients with chronic (CHR, n=3) or self-healing (SH, n=3) CL, and compared these to human macrophage responses. Transcriptomes of L. V. panamensis-infected PBMCs showed enrichment of functional gene categories derived from innate as well as adaptive immune cells signatures, demonstrating that Leishmania modulates adaptive immune cell functions as early as after 24h post interaction with PBMCs from previously unexposed healthy individuals. Among differentially expressed PBMC genes, four broad categories were commonly modulated by SH and CHR strains: cell cycle/proliferation/differentiation, metabolism of macromolecules, immune signaling and vesicle trafficking/transport; the first two were predominantly downregulated, and the latter upregulated in SH and CHR as compared to uninfected samples. Type I IFN signaling genes were uniquely up-regulated in PBMCs infected with CHR strains, while genes involved in the immunological synapse were uniquely downregulated in SH infections. Similarly, pro-inflammatory response genes were upregulated in isolated macrophages infected with CHR strains. Our data demonstrate that early responses during Leishmania infection extend beyond innate cell and/or phagocytic host cell functions, opening new frontiers in our understanding of the triggers and drivers of human CL.

Fatal Brucellosis Infection in a Liver Transplant Patient: A Case Report and Review of the Literature.

Brucellosis is the most common zoonosis, particularly in developing countries. The true incidence of human brucellosis is unknown. The WHO points out that 500,000 cases of brucellosis are reported each year from around the world. In Colombia, there is currently no regular surveillance of the event in humans and its prevalence is low due a low clinical suspicion. We report a case of a 66-year-old man, an urban merchant, who had received a liver transplant 11 years ago. The patient presented to the emergency department for two months of fatigue, severe myalgia, paresis of the extremities, loss of muscle strength, and progressive deterioration of functional class. In the emergency room, he became disoriented and was transferred to the intensive-care unit. He had a white blood cell count of 18990/uL and creatine phosphokinase 10302 U/L. Routine blood cultures were positive for Brucella melitensis. The patient reported consumption of unpasteurized bovine milk. He was treated with doxycycline and ciprofloxacin. Despite antibiotic management, after one month of hospitalization and in the context of septic shock with multiorgan failure, the patient died. Brucellosis is an unsuspected and underdiagnosed disease. It can occur in people with or without risk factors. Although the mortality is low, immunocompromised patients can develop fatal infections. A presumptive diagnosis can be established through the correlation of patient history and classic laboratory findings, which include transaminitis, anemia, and leukopenia with relative lymphocytosis; however, other findings can help us to guide the diagnosis, such as rhabdomyolysis, which appears as a complication in different infections; however, it had not been described before in brucellosis. A partnership between clinical suspicion laboratory diagnostic tests and improved disease surveillance systems is necessary to fight the disease.

Cerebral aneurysm rupture status classification using statistical and machine learning methods.

Morphological characterization and fluid dynamics simulations were carried out to classify the rupture status of 71 (36 unruptured, 35 ruptured) patient specific cerebral aneurysms using a machine learning approach together with statistical techniques. Eleven morphological and six hemodynamic parameters were evaluated individually and collectively for significance as rupture status predictors. The performance of each parameter was inspected using hypothesis testing, accuracy, confusion matrix, and the area under the receiver operating characteristic curve. Overall, the size ratio exhibited the best performance, followed by the diastolic wall shear stress, and systolic wall shear stress. The prediction capability of all 17 parameters together was evaluated using eight different machine learning algorithms. The logistic regression achieved the highest accuracy (0.75), whereas the random forest had the highest area under curve value among all the classifiers (0.82), surpassing the performance exhibited by the size ratio. Hence, we propose the random forest model as a tool that can help improve the rupture status prediction of cerebral aneurysms.

Development and validation of a scoring system for predicting cancer patients at risk of extended-spectrum b-lactamase-producing Enterobacteriaceae infections.

BACKGROUND: Extended-spectrum beta-lactamase producing Enterobacteriaceae (ESBL-PE) infections are frequent and highly impact cancer patients. We developed and validated a scoring system to identify cancer patients harboring ESBL-PE at the National Institute of Cancer of Colombia. METHODS: We retrospectively analyzed medical records of 1695 cancer patients. Derivation phase included 710 patients admitted between 2013 to 2015, ESBL-PE positive culture (n = 265) paired by month and hospitalization ward with Non-ESBL-PE (n = 445). A crude and weighted score was developed by conditional logistic regression. The model was evaluated in a Validation cohort (n = 985) with the same eligibility criteria between 2016 to 2017. RESULTS: The score was based on eight variables (reported with Odds Ratio and 95% confidence interval): Hospitalization ≥7 days (5.39 [2.46-11.80]), Hospitalization during the previous year (4, 87 [2.99-7.93]), immunosuppressive therapy during the previous 3 months (2.97 [1.44-6.08]), Neutropenia (1.90 [1.12-3.24]), Exposure to Betalactams during previous month (1.61 [1.06-2.42]), Invasive devices (1.51 [1.012-2.25]), Neoplasia in remission (2.78 [1.25-1.17]), No chemotherapy during the previous 3 months (1.90 [1.22-2.97]). The model demonstrated an acceptable discriminatory capacity in the Derivation phase, but poor in the Validation phase (Recipient Operating Characteristic Curve: 0.68 and 0.55 respectively). CONCLUSIONS: Cancer patients have a high prevalence of risk factors for ESBL-PE infection. The scoring system did not adequately discriminate patients with ESBL-PE. In a high-risk population, other strategies should be sought to identify patients at risk of resistant ESBL-PE infection.

Comparative Assessment of DNA Targets and Amplification Methods for Leishmania (Viannia) Detection in Human Samples.

Multiple polymerase chain reaction (PCR)-based approaches have been developed for Leishmania detection in clinical and laboratory samples, and this diversity limits inter-study comparisons, meta-analyses, and generalization of findings. Towards harmonization of a molecular tool for detection of Leishmania (Viannia) for research purposes, we evaluated the concordance of 18SrDNA quantitative polymerase chain reaction (qPCR) and minicircle kinetoplastid DNA (mkDNA) PCR followed by Southern blot (PCR-SB) in in vitro infection systems and in lesion and mucosal swab samples from Colombian patients with cutaneous leishmaniasis caused by L. (Viannia). The lower limit of parasite detection of 18SrDNA qPCR and mkDNA PCR-SB was 10-1 promastigotes and one intracellular amastigote per reaction. From cutaneous lesions (n = 63), an almost perfect concordance was found between the methods (κ = 0.92, 95% CI: 0.82-1.00). Despite equal limits of detection, mkDNA PCR-SB was more efficient for parasite detection in mucosal samples than 18SrDNA qPCR or 18SrDNA digital droplet PCR. The high concordance, sensitivity, scaling potential, and feasibility of implementation of the 18SrDNA qPCR, support its selection as the L. (Viannia) in research laboratories, as a first step towards harmonization of research protocols in the region.

Pharmacometabolomics of Meglumine Antimoniate in Patients With Cutaneous Leishmaniasis.

Control of cutaneous leishmaniasis (CL) in the Americas is dependent on chemotherapy with parenteral pentavalent antimonials. High rates of treatment failure urge the search for predictive and prognostic markers of therapeutic responsiveness. In this study, we aimed to identify biomarkers of therapeutic response during treatment with meglumine antimoniate (MA). We conducted untargeted metabolomic profiling of plasma samples from CL patients (n = 39; 25 who cured and 14 who did not cure), obtained before and at the end of treatment. Exposure to MA induced metabolic perturbations primarily reflecting alteration in long-chain fatty acid ß-oxidation and energy production. Allantoin, N-acetylglutamine, taurine, and pyruvate were significantly more abundant in samples from patients who responded to treatment, and were predictive and prognostic of treatment outcome in this patient cohort (AUC > 0.7). In an ex vivo model of infection, allantoin but not taurine enhanced the MA-dependent killing of intracellular Leishmania (Viannia) panamensis. Our results support the participation of metabolites mediating antioxidant and wound healing responses in clinical cure of CL, revealing relationships between metabolism and immune responses in the outcome of antileishmanial treatment.

Clinical and parasitological factors in parasite persistence after treatment and clinical cure of cutaneous leishmaniasis.

BACKGROUND: The determinants of parasite persistence or elimination after treatment and clinical resolution of cutaneous leishmaniasis (CL) are unknown. We investigated clinical and parasitological parameters associated with the presence and viability of Leishmania after treatment and resolution of CL caused by L. Viannia. METHODS: Seventy patients who were treated with meglumine antimoniate (n = 38) or miltefosine (n = 32) and cured, were included in this study. Leishmania persistence and viability were determined by detection of kDNA and 7SLRNA transcripts, respectively, before, at the end of treatment (EoT), and 13 weeks after initiation of treatment in lesions and swabs of nasal and tonsillar mucosa. RESULTS: Sixty percent of patients (42/70) had evidence of Leishmania persistence at EoT and 30% (9/30) 13 weeks after treatment initiation. A previous episode of CL was found to be a protective factor for detectable Leishmania persistence (OR: 0.16, 95%CI: 0.03-0.92). kDNA genotyping could not discern differences between parasite populations that persisted and those isolated at diagnosis. CONCLUSIONS: Leishmania persist in skin and mucosal tissues in a high proportion of patients who achieved therapeutic cure of CL. This finding prompts assessment of the contribution of persistent infection in transmission and endemicity of CL, and in disease reactivation and protective immunity.

Flow-induced wall mechanics of patient-specific aneurysmal cerebral arteries: Nonlinear isotropic versus anisotropic wall stress.

Fluid-structure interaction simulations of three patient-specific models of cerebral aneurysms were carried out with the objective of quantifying the effects of non-Newtonian blood flow and the vessel mechanical behavior on the time-dependent fluid shear and normal stresses, and structural stress and stretch. The average wall shear stress at peak systole was found to be approximately one order of magnitude smaller than the shear stresses in the proximal communicating arteries, regardless of the shape or size of the aneurysms. Spatial distributions of oscillatory shear index were consistent with the reciprocal of wall shear stress distributions at peak systole for all aneurysm geometries, demonstrating that oscillatory shear index correlates inversely with wall shear at this time point in the cardiac cycle. An aneurysm wall modeled with an isotropic material resulted in an underestimation of both the maximum principal stress and stretch, compared to the anisotropic material model. For the three aneurysm geometries, anisotropic peak wall stresses were approximately 50% higher than for an isotropic material. Regardless of the constitutive material, the maximum stresses were consistently located at the aneurysm neck; stresses in the dome were 30% of those in the neck.

Fluid structural analysis of human cerebral aneurysm using their own wall mechanical properties.

Computational Structural Dynamics (CSD) simulations, Computational Fluid Dynamics (CFD) simulation, and Fluid Structure Interaction (FSI) simulations were carried out in an anatomically realistic model of a saccular cerebral aneurysm with the objective of quantifying the effects of type of simulation on principal fluid and solid mechanics results. Eight CSD simulations, one CFD simulation, and four FSI simulations were made. The results allowed the study of the influence of the type of material elements in the solid, the aneurism's wall thickness, and the type of simulation on the modeling of a human cerebral aneurysm. The simulations use their own wall mechanical properties of the aneurysm. The more complex simulation was the FSI simulation completely coupled with hyperelastic Mooney-Rivlin material, normal internal pressure, and normal variable thickness. The FSI simulation coupled in one direction using hyperelastic Mooney-Rivlin material, normal internal pressure, and normal variable thickness is the one that presents the most similar results with respect to the more complex FSI simulation, requiring one-fourth of the calculation time.

Numerical investigation of the hemodynamics in anatomically realistic lateral cerebral aneurysms.

Hemodynamically induced stress plays an important role in the progression and rupture of cerebral aneurysms. The current work describes computational fluid dynamics (CFD) simulations in anatomically realistic models of cerebral aneurysms. Twenty lateral aneurysms models were investigated. The models were obtained from three-dimensional rotational angiographic imaging data and CFD were studied under the same physiologically representative waveform of inflow. The flow was assumed to be laminar, non-Newtonian, and incompressible. The CFD models were solved with the finite elements package ADINA. Predictions of velocity field and wall shear stress (WSS) on the aneurysms were compared for the different cases. Linear correlations between the WSS on the aneurysm fundus at peak systole for lateral aneurysms with an area index were found.

Síndrome de la arteria mesentérica superior o síndrome de Wilkie / Superior Mesenteric Artery Syndrome or Wilkie Syndrome

Describimos tres casos de síndrome de arteria mesentérica superior (SAMS), también conocido como síndrome de Wilkie, ileus duodenal crónico, o por órtesis ortopédicas (“cast syndrome”) El síndrome ocurre por la compresión de la tercera porción del duodeno entre la arteria mesentérica superior y la aorta. Los principales riesgos relacionados con la aparición del síndrome son la pérdida rápida de peso y las cirugías de columna vertebral. La presentación clínica del síndrome es variable e inespecífica, e incluye náuseas, vómito, dolor abdominal y pérdida de peso. El diagnóstico se basa en los hallazgos de la compresión duodenal por la arteria mesentérica superior por endoscopia, radiología contrastada y tomografía. El tratamiento se dirige a corregir la causa de base, la cual frecuentemente se relaciona con la pérdida de peso. Por lo tanto, el manejo es inicialmente conservador con nutrición suplementaria y se reserva la cirugía para aquellos casos que no respondan a la terapia nutricional.

We described three cases of superior mesenteric artery (SMA) syndrome, also known as Wilkie’s syndrome, chronic duodenal ileus, or cast syndrome. This syndrome occurs when the third portion of the duodenum is compressed between the SMA and the aorta. The major risk factors for development of SMA syndrome are rapid weight loss and surgical correction of spinal deformities. The clinical presentation of SMA syndrome is variable and nonspecific, including nausea, vomiting, abdominal pain, and weight loss. The diagnosis is based on endoscopic, radiographic and tomographic findings of duodenal compression by the SMA. The treatment of SMA syndrome is aimed at the precipitating factor, which usually is related to weight loss. Therefore, conservative therapy with nutritional supplementation is the initial approach, and surgery is reserved for those who do not respond to nutritional therapy.