Modification of Superabsorbent Polymer Granules and Fibers for Antimicrobial Efficacy and Malodor Control

Superabsorbent polymer (SAP) granules, typically used in personal care devices such as diapers, incontinence devices, hygiene pads, and wound dressings, and granular particles of zeolite and bentonite were each subjected to modification by exposure to solutions of 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) in ethanol at room temperature. The air-dried granules showed newly acquired properties attributable to the presence of active chlorine (Cl+). The treated particles effectively oxidized the malodorant 3-mercapto-3-methylbutanol (3M3MB). MC-treated granules inactivated urease, a microbial exoenzyme commonly involved in ammonia production. Modified SAP granules and superabsorbent fibers (SAFs) showed powerful antibacterial activity in an in vitro chronic wound model. The results suggest that processing of SAP granules and SAFs by this simple method at an industrial scale could add value to their widespread use in a variety of personal hygiene devices and specifically to the improvement of chronic wound care.

Mesalamine induced hepatotoxicity. Is mesalamine safe?

Dear Editor: Mesalamine is a medication used widely in the treatment of patients with inflammatory bowel disease. Although mesalamine is considered safe, hepatotoxicity has been reported with an incidence of 0-4%. We present the clinical picture of a patient with hepatotoxicity due to mesalamine. A 79-year-old woman in the context of chronic diarrhea, a left-sided ulcerative colitis diagnosis was made, and treatment was initiated with oral mesalamine 4 g per day, and mesalamine suppositories. Before starting treatment, she had normal liver test results. After three months, she presented with headache, fatigue, and intermittent low fever. Her laboratory tests showed a liver profile with a cholestatic pattern, and elevation of inflammatory parameters. Mesalamine was suspended, and an extensive study was performed. Cholangioresonance reported intra and extrahepatic bile duct dilation without obstruction, and thickening of the intrahepatic bile duct. She progressed with worsening of the liver profile without signs of liver failure. A liver biopsy was performed, which showed chronic non-suppurative cholangitis with granulomas and focal concentric fibrosis related to medium-caliber bile ducts, and IgG4 stain was negative.

Effectiveness of infliximab in common variable immunodeficiency associated with enteropathy

Common Variable Immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency in adults, with non-infectious gastrointestinal involvement present in up to 50% of patients, with the small intestine and colon being the most affected areas. Reports have evaluated the effectiveness of biologic therapy in this scenario. Here, we describe the clinical, endoscopic, and histological findings of a patient who presented a satisfactory response to infliximab.

Percutaneous Balloon Compression for the Treatment of Trigeminal Neuralgia: A Review of 10 Years of Clinical Experience

BACKGROUND

Trigeminal neuralgia (TN) is defined as a spontaneous painful sensation in the trigeminal nerve territory. The pain intensity of TN is classified into different grades of suffering that affect a patient's quality of life. Percutaneous balloon compression of the ganglion is a neurosurgical option that is easy, reproducible, and can reduce the morbidity of TN.

METHODS

We retrospectively analyzed all patients treated with trigeminal nerve percutaneous balloon compression at the Clinical Hospital of the University of Chile between January 2012 and May 2022. Data collected from electronic records included demographic information, medical and surgical history, type of anesthesia and drugs used during surgery, balloon inflation time, surgery time, operative room time, intraoperative events, postoperative complications, duration of hospitalization, and duration of follow-up.  Results: We identified 63 patients who met our inclusion criteria. The median patient age was 62 years (interquartile range [IQR] 57-69 years). Sixty-five percent of the patients were female. The simultaneous involvement of the second and third branches of the trigeminal nerve was the most frequent symptom. Before surgery, the patients experienced an average of 6.6 years of pain (IQR 2-10 years). Right neuralgia was the most frequent laterality type (69%). Forty percent of the patients had a previous surgical procedure for neuralgia, with treatment failure being the most frequent surgical indication (63%). According to the procedure, the mean balloon insufflation volume was 0.89±0.12 mL with a median compression time of 2.5 min (IQR 2.1-4.0 min). No hemorrhagic complications were observed. Furthermore, during follow-up, there were no surgical complications among any of the patients; however, 6.4% of patients required a second intervention. The pain-free period was two years in 60% of patients and five years in 23% of patients.

CONCLUSIONS

TN is a painful condition. Although there are multiple surgical approaches, we believe that percutaneous balloon compression is an excellent alternative treatment option that offers high effectiveness, low morbidity, and low hospital stay.

Customizable, reconfigurable, and anatomically coordinated large-area, high-density electromyography from drawn-on-skin electrode arrays

Accurate anatomical matching for patient-specific electromyographic (EMG) mapping is crucial yet technically challenging in various medical disciplines. The fixed electrode construction of multielectrode arrays (MEAs) makes it nearly impossible to match an individual's unique muscle anatomy. This mismatch between the MEAs and target muscles leads to missing relevant muscle activity, highly redundant data, complicated electrode placement optimization, and inaccuracies in classification algorithms. Here, we present customizable and reconfigurable drawn-on-skin (DoS) MEAs as the first demonstration of high-density EMG mapping from in situ-fabricated electrodes with tunable configurations adapted to subject-specific muscle anatomy. The DoS MEAs show uniform electrical properties and can map EMG activity with high fidelity under skin deformation-induced motion, which stems from the unique and robust skin-electrode interface. They can be used to localize innervation zones (IZs), detect motor unit propagation, and capture EMG signals with consistent quality during large muscle movements. Reconfiguring the electrode arrangement of DoS MEAs to match and extend the coverage of the forearm flexors enables localization of the muscle activity and prevents missed information such as IZs. In addition, DoS MEAs customized to the specific anatomy of subjects produce highly informative data, leading to accurate finger gesture detection and prosthetic control compared with conventional technology.

Baseline Findings of PreventE4: A Double-Blind Placebo Controlled Clinical Trial Testing High Dose DHA in APOE4 Carriers before the Onset of Dementia

INTRODUCTION

Lower blood levels of the omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) are correlated with worse cognitive functions, particularly among APOE ε4 carriers. Whether DHA supplementation in APOE ε4 carriers with limited DHA consumption and dementia risk factors can delay or slow down disease progression when started before the onset of clinical dementia is not known.

METHODS

PreventE4 is a double-blind, single site, randomized, placebo-controlled trial in cognitively unimpaired individuals with limited omega-3 consumption and dementia risk factors (n=368). Its objectives are to determine (1) whether carrying the APOE ε4 allele is associated with lower delivery of DHA to the brain; and (2) whether high dose DHA supplementation affects brain imaging biomarkers of AD and cognitive function.

RESULTS

365 cognitively unimpaired individuals between 55 and 80 (mean age 66) were randomized to 2 grams of DHA per day or identically appearing placebo for a period of 2 years. Half the participants were asked to complete lumbar punctures at baseline and 6-month visits to obtain cerebrospinal fluid (CSF). The primary trial outcome measure is the change in CSF DHA to arachidonic acid ratio after 6 months of the intervention (n=181). Secondary trial outcomes include the change in functional and structural connectivity using resting state functional MRI at 24 months (n=365). Exploratory outcomes include the change in Repeatable Battery of the Assessment of Neuropsychological Status at 24 months (n=365).

CONCLUSIONS

Findings from PreventE4 will clarify the brain delivery of DHA in individuals carrying the APOE ε4 allele with implications for dementia prevention strategies. Trial was registered as NCT03613844.

Continuous prolonged prone positioning in COVID-19-related ARDS: a multicenter cohort study from Chile

Background

Prone positioning is currently applied in time-limited daily sessions up to 24 h which determines that most patients require several sessions. Although longer prone sessions have been reported, there is scarce evidence about the feasibility and safety of such approach. We analyzed feasibility and safety of a continuous prolonged prone positioning strategy implemented nationwide, in a large cohort of COVID-19 patients in Chile.

Methods

Retrospective cohort study of mechanically ventilated COVID-19 patients with moderate-to-severe acute respiratory distress syndrome (ARDS), conducted in 15 Intensive Care Units, which adhered to a national protocol of continuous prone sessions  ≥ 48 h and until PaO2:FiO2 increased above 200 mm Hg. The number and extension of prone sessions were registered, along with relevant physiologic data and adverse events related to prone positioning. The cohort was stratified according to the first prone session duration: Group A, 2–3 days; Group B, 4–5 days; and Group C, > 5 days. Multivariable regression analyses were performed to assess whether the duration of prone sessions could impact safety.

Results

We included 417 patients who required a first prone session of 4 (3–5) days, of whom 318 (76.3%) received only one session. During the first prone session the main adverse event was grade 1–2 pressure sores in 97 (23.9%) patients; severe adverse events were infrequent with 17 non-scheduled extubations (4.2%). 90-day mortality was 36.2%. Ninety-eight patients (24%) were classified as group C; they exhibited a more severe ARDS at baseline, as reflected by lower PaO2:FiO2 ratio and higher ventilatory ratio, and had a higher rate of pressure sores (44%) and higher 90-day mortality (48%). However, after adjustment for severity and several relevant confounders, prone session duration was not associated with mortality or pressure sores.

Conclusions

Nationwide implementation of a continuous prolonged prone positioning strategy for COVID-19 ARDS patients was feasible. Minor pressure sores were frequent but within the ranges previously described, while severe adverse events were infrequent. The duration of prone session did not have an adverse effect on safety.

Drawn-on-Skin Sensors from Fully Biocompatible Inks toward High-Quality Electrophysiology

The need to develop wearable devices for personal health monitoring, diagnostics, and therapy has inspired the production of innovative on-demand, customizable technologies. Several of these technologies enable printing of raw electronic materials directly onto biological organs and tissues. However, few of them have been thoroughly investigated for biocompatibility of the raw materials on the cellular, tissue, and organ levels or with different cell types. In addition, highly accurate multiday in vivo monitoring using such on-demand, in situ fabricated devices has yet to be done. Presented herein is the first fully biocompatible, on-skin fabricated electronics for multiple cell types and tissues that can capture electrophysiological signals with high fidelity. While also demonstrating improved mechanical and electrical properties, the drawn-on-skin ink retains its properties under various writing conditions, which minimizes the variation in electrical performance. Furthermore, the drawn-on-skin ink shows excellent biocompatibility with cardiomyocytes, neurons, mice skin tissue, and human skin. The high signal-to-noise ratios of the electrophysiological signals recorded with the DoS sensor over multiple days demonstrate its potential for personalized, long-term, and accurate electrophysiological health monitoring.

Comparative Analysis of Reconfigurable Platforms for Memristor Emulation

The memristor is the fourth fundamental element in the electronic circuit field, whose memory and resistance properties make it unique. Although there are no electronic solutions based on the memristor, interest in application development has increased significantly. Nevertheless, there are only numerical Matlab or Spice models that can be used for simulating memristor systems, and designing is limited to using memristor emulators only. A memristor emulator is an electronic circuit that mimics a memristor. In this way, a research approach is to build discrete-component emulators of memristors for its study without using the actual models. In this work, two reconfigurable hardware architectures have been proposed for use in the prototyping of a non-linearity memristor emulator: the FPAA (Field Programing Analog Arrays) and the FPGA (Field Programming Gate Array). The easy programming and reprogramming of the first architecture and the performance, high area density, and parallelism of the second one allow the implementation of this type of system. In addition, a detailed comparison is shown to underline the main differences between the two approaches. These platforms could be used in more complex analog and/or digital systems, such as neural networks, CNN, digital circuits, etc.

Herpetic Esophagitis and Eosinophilic Esophagitis: A Potential Association

BACKGROUND Gastroesophageal reflux disease, infectious esophagitis, and eosinophilic esophagitis are the most frequent causes of esophagitis, the latter 2 etiologies being generally considered independently. However, the association between both entities has been suggested through case reports in immunocompetent patients. CASE REPORT We present the case of an immunocompetent 26-year-old man presenting with fever, adynamia, retrosternal pain, and dysphagia. Endoscopy was performed, showing whitish lesions in circular plates with erosions, and in some depressed areas in the middle and distal esophagus. Biopsies showed the presence of ulcerated foci covered by fibrinoleukocyte exudate in granulation tissue and nuclear inclusions with a viral appearance. The immunohistochemical study for herpes simplex virus (HSV) was positive. The patient was treated symptomatically and progressed favorably. The endoscopic control carried out at 3 months showed longitudinal grooves and trachealization, findings compatible with the diagnosis of eosinophilic esophagitis and with biopsies that confirmed the etiology by showing an increase in eosinophil count >20 per field, without isolating HSV. CONCLUSIONS This clinical case confirms the possible relationship between esophagitis caused by HSV and eosinophilic esophagitis. Alterations at the immune level and damage to the esophageal mucosa barrier may explain this relationship. In this scenario, an endoscopic follow-up should be considered.

Anal neoplasia and perianal Crohn's disease: myth or reality?

The association between Inflammatory Bowel Disease (IBD) and anal canal squamous cell carcinoma (SCC) has a low prevalence and is mainly supported by articles that include a series of cases. We describe the clinical, endoscopic and histological findings of a patient with Crohn's disease (CD) who, while undergoing biological therapy and active disease, developed SCC.

Endovascular Treatment of Small and Very Small Intracranial Aneurysms with the Woven EndoBridge Device

BACKGROUND AND PURPOSE

The Woven EndoBridge has proved to be a safe and effective treatment, especially for wide-neck intracranial aneurysms. The recent fifth-generation Woven EndoBridge came with smaller devices. The purpose of this study was to assess the safety and efficiency of Woven EndoBridge treatment of small and very small aneurysms.

MATERIALS AND METHODS

Between September 2017 and March 2020, all consecutive patients treated with a 3- or 3.5 mm-width Woven EndoBridge device were included in this retrospective intention-to-treat study. Clinical and radiologic findings were evaluated at immediate and last-available follow-up. Angiographic outcome was assessed by an external expert reader.

RESULTS

One hundred twenty-eight aneurysms were treated with a fifth-generation Woven EndoBridge device including 29 with a width of ≤3.5 mm. Ten aneurysms were ruptured (34%). In 3 cases (10%), Woven EndoBridge treatment could not be performed because the aneurysm was still too small for the smallest available Woven EndoBridge device and another endovascular strategy was chosen. The median follow-up time was 11.2 months. Complete and adequate occlusion was obtained in 71% and 90% of the treated aneurysms, respectively. Retreatment was needed in 2 cases (10%). Symptomatic ischemic complications leading to transient neurologic deficits occurred in 2 cases (7%) (1 procedure-related and 1 device-related) but with full spontaneous recovery at discharge.

CONCLUSIONS

The fifth-generation Woven EndoBridge device seems to be a safe and technically feasible treatment for both ruptured and unruptured small and very small intracranial aneurysms, with satisfactory occlusion rates on midterm follow-up. However, further study is needed to evaluate longer-term efficiency.

Modeling the coating layer thickness in a pharmaceutical coating process

Although mechanistic numerical simulations can offer great insights into a process, they are limited with respect to resolved process time. While statistical models provide long-term predictability, determining the underlying probability distributions is often challenging. In this work, detailed CFD-DEM simulations of a pharmaceutical Wurster coating process for microspheres are used to evaluate the input parameters for a novel Monte-Carlo simulation approach. The combined strengths of both modeling approaches make it possible to predict the coating mass and thickness distributions over the entire process time. It was observed that smaller beads receive a thicker coating layer since they pass the spray zone closer to the nozzle. Moreover, it was established that, in contrast to the airflow rate, the spray rate has a great impact on the inter-particle coating variability. A stochastic model was developed to investigate the relative contribution of coating layer variability and fill weight variability to the product non-uniformity in a capsule filling process of Multiple Unit Pellet Systems (MUPS).

Leflunomide as a cause of collagenous colitis: an entity to consider

Leflunomide belongs to the group of disease-modifying anti-rheumatic drugs (DMARDs) used in the treatment of psoriatic, rheumatoid, and reactive arthritis. Approximately 20% of patients will experience some adverse event, highlighting weight loss, abdominal pain and diarrhea. We describe the clinical, endoscopic, and histological findings in a patient with psoriatic arthritis (PA) who developed severe chronic diarrhea after drug use.

Delphi Project on the trends in Implant Dentistry in the COVID-19 era: Perspectives from Latin America

AIM

To establish trends in Implant Dentistry in Latin America in the COVID-19 pandemic.

MATERIAL AND METHODS

A steering committee and an advisory group of experts in Implant Dentistry were selected among eighteen countries. An open-ended questionnaire by Delphi methodology was validated including 64 questions, divided in 7 topics, concerning the various trends in dental implantology. The survey was conducted in two rounds, which provided the participants in the second round with the results of the first. The questionnaires were completed on August 2020, and the online meeting conference was held on September 2020. The final prediction was developed through consensus by a selected group of experts.

RESULTS

A total of 197 experts from Latin America answered the first and second questionnaire. In the first round, the established threshold for consensus (65%) was achieved in 30 questions (46.87%). In the second round, performed on average 45 days later, this level was achieved in 47 questions (73.43%). Consensus was completely reached on the item "Diagnostic" (100%), the field with the lowest consensus was "Demand for treatment with dental implants" (37.5%).

CONCLUSIONS

The present study in Latin America has provided relevant and useful information on the predictions in the education and practice of Implant Dentistry in the COVID-19 era. The consensus points toward a great confidence of clinicians in the biosecurity protocols used to minimize the risk of SARS-CoV-2 transmission. It is foreseen as an important change in education, with introduction of virtual reality and other simulation technologies in implant training.

Effects of alirocumab on carotid plaque lipid content and inflammation: a time course study using serial vessel wall imaging

Background

PCSK9 inhibition has emerged as a potent pharmaceutical approach to lowering LDL cholesterol (LDL-C). Monoclonal anti-PCSK9 antibodies have been shown in recent clinical trials to reduce cardiovascular events in patients with atherosclerotic cardiovascular disease, but the underlying mechanisms are not fully understood. Meanwhile, circulatory inflammation markers were not reduced with PCSK9 inhibitors, thus their effects on plaque inflammation remain elusive. Vessel wall imaging with magnetic resonance (VW-MRI) has enabled serial monitoring of changes in carotid plaque lipid content and inflammation noninvasively that correlates with coronary and carotid vascular events.

Purpose

Using serial VW-MRI, we studied the effects and time course of PCSK9 inhibition with alirocumab on carotid plaque lipid content and inflammation.

Methods

Patients with LDL-C ≥70 mg/dl on ≤70 mg per week atorvastatin or an equivalent (due to statin intolerance or treating-physician discretion) and soft carotid plaque(s) identified on ultrasound underwent carotid VW-MRI. Those with confirmed lipid-rich plaque(s) on VW-MRI received alirocumab (150 mg subcutaneously every other week) and were re-scanned at 3, 6, and 12 months after treatment. Carotid VW-MRI included pre- and post-contrast images for measuring percent lipid-rich necrotic core volume (%LRNC) and dynamic contrast-enhanced images for measuring the extravasation rate of gadolinium contrast (Ktrans, reflecting tissue blood flow, endothelial surface area, and microvessel permeability), a marker of plaque inflammation. The co-primary endpoints were changes in %LRNC and Ktrans at 12 months from baseline.

Results

Of 31 patients enrolled, 27 completed the study (mean age: 69±9; male: 67%; on statins and/or ezetimibe: 41%; median LDL-C: 120 mg/dl [interquartile range: 99, 158]). Alirocumab induced a 59% reduction in LDL-C (p<0.001) on average at 3 months to a median of 54 mg/dl (interquartile range: 29, 69), which was maintained at later time points. From 9.8% at baseline, %LRNC was progressively reduced to 8.4% at 3 months, 7.5% at 6 months, and 7.2% at 12 months, representing a rapid 14% reduction (p=0.032) at 3 months and a total reduction of 20% (p=0.019) at 12 months. From 0.07±0.02 min-1 at baseline, Ktrans was not reduced at 3 or 6 months but was significantly reduced by 17% (p=0.029) at 12 months to 0.06±0.02 min-1. No significant changes in lumen or wall area were observed during the study period.

Conclusions

Serial VW-MRI documented plaque-stabilizing effects of PCSK9 inhibition with alirocumab, including plaque delipidation and attenuation of plaque inflammation. The reduction in plaque lipid content was apparent as early as 3 months. The reduction in Ktrans was not seen until 12 months of treatment and may indicate a later effect on microvascular structure and/or function. This observation represents the earliest time course of plaque morphology modification by non-statin therapy reported to date.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): The study was funded by an investigator-initiated grant from Regeneron and Sanofi.

Ultra-conformal drawn-on-skin electronics for multifunctional motion artifact-free sensing and point-of-care treatment

An accurate extraction of physiological and physical signals from human skin is crucial for health monitoring, disease prevention, and treatment. Recent advances in wearable bioelectronics directly embedded to the epidermal surface are a promising solution for future epidermal sensing. However, the existing wearable bioelectronics are susceptible to motion artifacts as they lack proper adhesion and conformal interfacing with the skin during motion. Here, we present ultra-conformal, customizable, and deformable drawn-on-skin electronics, which is robust to motion due to strong adhesion and ultra-conformality of the electronic inks drawn directly on skin. Electronic inks, including conductors, semiconductors, and dielectrics, are drawn on-demand in a freeform manner to develop devices, such as transistors, strain sensors, temperature sensors, heaters, skin hydration sensors, and electrophysiological sensors. Electrophysiological signal monitoring during motion shows drawn-on-skin electronics' immunity to motion artifacts. Additionally, electrical stimulation based on drawn-on-skin electronics demonstrates accelerated healing of skin wounds.

Extradural minipterional approach: Evolving indications of the minipterional craniotomy

Background:

In this paper, we report a clinical series of skull base lesions operated on trough the MiniPT, extending its application to skull base lesions, either using the classical minipterional or a variant, we call extradural minipterional approach (MiniPTEx).

Methods:

We describe our surgical technique of operating on complex skull base lesions using a minipterional extradural approach. Anterior clinoidectomy, middle fossa peeling, transcavernous, and Kawase approaches were performed as needed. In total, we carried out 24 surgeries: three skull base tumors, 1 Moyamoya case, and 20 giant/complex intracranial aneurysms. All the patients present good neurological result (mRs < 3). Only two patients had paralysis of any cranial nerve and only one patient had a mild hemiparesis.

Results:

This surgery series there are 24 cases, 10 patients were treated with exclusive MiniPT. MiniPT extradural approach was made in 14 patients. Twelve were treated using pure MiniPTEx approach, 1 patient using transcavernous approach, and in 1 patient, the anterior clinoid was resected with the combination of a MiniPT, a medium fossa peeling, and the Kawase anterior petrosectomy for skull base surgery.

Conclusion:

We further advance the indications of the MiniPT by extending it to operate on the cranial base tumors or complex vascular lesions without additional morbidity. MiniPT approach may be safely associated with skull base techniques, including anterior and posterior clinoidectomies, peeling of the middle fossa, transcavernous approach, and anterior petrosectomy. The versatility of the MiniPT craniotomy and the feasibility of performing skull base surgery through the MiniPT technique have been demonstrated in this paper.

[Continuous intra arterial nimodipine for vasospasm secondary to subarachnoid hemorrhage. Report of one case]

We report a 39-year-old male with an aneurysmal subarachnoid hemorrhage without hydrocephalus, in whom a right choroidal aneurysm was early excluded by endovascular coil insertion. Intracranial pressure (PIC) and cerebral oxygenation (PtiO2) sensors for neuromonitoring were installed due to a persistent comatose state. From the 3rd day, neuromonitoring became altered. CT angiography and cerebral angiography showed severe proximal and distal vasospasm (VE) of the middle (ACM) and anterior (ACA) right cerebral arteries. VE was treated with angioplasty and intravenous nimodipine. Forty eight hours later, despite hemodynamic maximization, neuromonitoring became altered again, mainly explained by a decrease in PtiO2 below 15 mmHg. A severe VE in ACM and right ACA was confirmed by angiography. Given the presence of an early and recurrent VE, which was associated with a decrease in cerebral oxygenation, internal carotid micro-catheters for continuous nimodipine infusion were installed. This therapy maintained a normal neuromonitoring for 15 days. During this period, attempts were done to decrease or discontinue the infusion, but the patient presented parallel falls of cerebral oxygenation or decreased cerebral perfusion observed with perfusion CT, interpreted as persistent VE. Finally, the infusion was stopped at day 15 without significant complication. We conclude that intra-arterial nimodipine continuous infusion in refractory VE can be useful and safe in selected patients. Multimodal neuromonitoring is essential.

Effect of FOLFOX on minimal residual disease in Stage III colon cancer and risk of relapse

Introduction

25% of Stage III colon cancer patients relapse within 5 years due to minimal residual disease (MRD) not eliminated by surgery and chemotherapy. We hypothesise that sub-types of MRD, defined by circulating tumour cells (CTCs) and bone marrow micro-metastasis (mM) have different types and kinetics of relapse.

Patients and Methods

One month of curative surgery and 1 month after completing six cycles of FOLFOX chemotherapy blood and bone marrow samples were taken to detect CTCs and mM using immunocytochemistry with anti-carcino-embryonic antigen (CEA). Follow up was up to 5 years or disease progression defined as new images on CT scanning. Survival curves using Kaplan–Meier (KM) and Restricted Mean Survival Time (RMST) were calculated for three prognostic groups: CTC and mM negative, CTC negative mM positive, and CTC positive.

Results

76 patients (39 men) participated, mean age 67 years, median follow-up 3.6 years. The response to chemotherapy was heterogeneous and MRD pre-treatment did not predict response to therapy. Of 21 patients MRD (−), 20 remained MRD negative and one patient became mM (+); of 21 patients mM (+), 10 became MRD (−), 8 remained the same and 3 became CTC (+); of the 34 CTC positive, 8 became MRD (−), 8 with only mM, and 18 remained positive.

After chemotherapy, 38 patients were negative for CTC and mM, 17 were positive for only mM, and 21 for CTCs. For the whole cohort, the 5 year KM was 58%, the median survival was not reached. For the three prognostic groups, the KM 5-year survivals were 87%, 58%, and 4%, respectively, the median survival for patients MRD negative and mM only was not reached. RMST for the whole cohort was 3.6 years, for the three prognostic groups the RMST was 4.6 years, 4.0 years, and 1.5 years, respectively. Serum CEA was significantly higher pre-surgery in the CTC positive group. There were no significant differences with respect to age or sex between the three groups.

Conclusions

MRD subtypes pre-chemotherapy did not predict treatment response. Post-chemotherapy MRD subtypes were associated with the pattern of failure and time to failure. MRD negative patients had an excellent prognosis with 87% disease-free survival at 5 years. Those with only mM had a similar outcome up to 2 years and then were at increasing risk of late failure. Patients who were CTC positive had a high risk of early failure. MRD subclassification may be useful to define the risk of relapse in Stage III colon cancer patients and warrants further studies with a larger number of patients.

l-NIL prevents the ischemia and reperfusion injury involving TLR-4, GST, clusterin, and NFAT-5 in mice

On renal ischemia-reperfusion (I/R) injury, recruitment of neutrophils during the inflammatory process promotes local generation of oxygen and nitrogen reactive species, which, in turn, are likely to exacerbate tissue damage. The mechanism by which inducible nitric oxide synthase (iNOS) is involved in I/R has not been elucidated. In this work, the selective iNOS inhibitor l- N6-(1-iminoethyl)lysine (l-NIL) and the NOS substrate l-arginine were employed to understand the role of NOS activity on the expression of particular target genes and the oxidative stress elicited after a 30-min of bilateral renal ischemia, followed by 48-h reperfusion in Balb/c mice. The main findings of the present study were that pharmacological inhibition of iNOS with l-NIL during an I/R challenge of mice kidney decreased renal injury, prevented tissue loss of integrity, and improved renal function. Several novel findings regarding the molecular mechanism by which iNOS inhibition led to these protective effects are as follows: 1) a prevention of the I/R-related increase in expression of Toll-like receptor 4 (TLR-4), and its downstream target, IL-1β; 2) reduced oxidative stress following the I/R challenge; noteworthy, this study shows the first evidence of glutathione S-transferase (GST) inactivation following kidney I/R, a phenomenon fully prevented by iNOS inhibition; 3) increased expression of clusterin, a survival autophagy component; and 4) increased expression of nuclear factor of activated T cells 5 (NFAT-5) and its target gene aquaporin-1. In conclusion, prevention of renal damage following I/R by the pharmacological inhibition of iNOS with l-NIL was associated with the inactivation of proinflammatory pathway triggered by TLR-4, oxidative stress, renoprotection (autophagy inactivation), and NFAT-5 signaling pathway.

Unassisted percutaneous tracheostomy: A new flow chart decision making based on simple physical conditions

INTRODUCTION

Percutaneous dilatation tracheostomy (PDT) has several advantages over traditional surgical tracheostomy. However, it is still performed using bronchoscopy guidance.

OBJECTIVE

To suggest the safety of unassisted PDT, without bronchoscopy guidance, based on bed-side screening flow chart evaluation.

MATERIAL AND METHODS

180 consecutive UCI patients referred to tracheostomy were submitted to Avalo's Screening Chart (ASC), in order to decide surgical technique.

RESULTS

161 patients were referred to unassisted PDT (un PDT) and 19 to surgical tracheostomy (ST) due to nonfulfillment of ASC steps. 10 patients submitted to unassisted PDT presented early complications, 8 presented mild bleeding and 2 false tracts. None of 6 months follow up patients presented long term complications.

CONCLUSION

The authors suggest unPDT is a safety surgical method in UCI patients who were submitted and approved to an easy anatomical and clinical screening chart (ASC).

Prostate tumor-induced angiogenesis is blocked by exosomes derived from menstrual stem cells through the inhibition of reactive oxygen species

Mesenchymal stem cells (MSCs) secrete exosomes that are capable of modifying the tumor environment through different mechanisms including changes in the cancer-cell secretome. This activity depends on their cargo content that is largely defined by their cellular origin. Endometrial cells are fine regulators of the angiogenic process during the menstrual cycle that includes an angiostatic condition that is associated with the end of the cycle. Hence, we studied the angiogenic activity of menstrual stem cells (MenSCs)-secreted exosomes on prostate PC3 tumor cells. Our results showed that exosomes induce a reduction in VEGF secretion and NF-κB activity. Lower reactive oxygen species (ROS) production in exosomes-treated cells was detected by the DCF method, suggesting that the inhibition of the intracellular ROS impacts both NF-κB and VEGF pathways. We confirmed using tubule formation and plug transplantation assays that MenSCs-exosomes suppress the secretion of pro-angiogenic factors by the PC3 cells in a ROS-dependent manner. The inhibition of the tumor angiogenesis and, consequently, the tumor growth was also confirmed using a xenograft mouse model. Additionally, the anti-tumoral effect was associated with a reduction of tumor hemoglobin content, vascular density and inhibition of VEGF and HIF-1α expression. Importantly, we demonstrate that the exosomes anti-angiogenic effect is specific to the menstrual cell source, as bone marrow MSCs-derived exosomes showed an opposite effect on the VEGF and bFGF expression in tumor cells. Altogether, our results indicate that MenSCs-derived exosomes acts as blockers of the tumor-induced angiogenesis and therefore could be suitable for anti-cancer therapies.

EGFR pathway subgroups in Chilean colorectal cancer patients, detected by mutational and expression profiles, associated to different clinicopathological features

Colorectal cancer is a multistep process affecting several signaling pathways including EGFR (epidermal growth factor receptor), a therapeutic target for metastatic disease. Our aim was to characterize the mutational and expression profiles of the EGFR pathway in colorectal tumors and to integrate these results according to five previously defined groups. We screened seven genes for mutations ( KRAS-BRAF-PIK3CA-PIK3R1-AKT1-MAP2K1-PTEN) and six proteins (EGFR-p110α-p85α-PTEN-phosphoAKT-phosphoMEK1) by immunohistochemistry, PTEN deletion, and MSI. At least one mutated gene was observed in 68% of tumors ( KRAS 45%, PIK3CA 21%, BRAF 14%, and PTEN 7%). PTEN deletion was observed in 10.7% of tumors and 19.6% were MSI-High. In all, 54% of tumors showed a high EGFR expression, 48% p110α, 4.4% phosphoAKT, and 22% phosphoMEK1; and 43% showed low PTEN expression and 22% p85α. In total, five groups of tumors were defined based on MSI, BRAF, and KRAS mutations. Three groups gather mainly early-stage tumors, whereas a fourth group is mostly conformed by advanced tumors. We described here that 71.4% of tumors from one group have a mutated PI3K/PTEN pathway, in comparison to other groups having 32%, 27%, and 25%. In addition, the five groups are differentiated by molecular features such as EGFR, p85α, p110α, and PTEN, showing variable expression among tumor groups. In conclusion, alterations on the EGFR pathway were found in a high percentage of colorectal cancer patients. Using the integration of diverse molecular markers, we ratified previous classification in an ethnic group having relevant genetic differences and living in a different environmental background, adding complementary molecular targets related to therapy.

Nitric oxide synthase and changes in oxidative stress levels in embryonic kidney observed in a rabbit model of intrauterine growth restriction

OBJECTIVE

This work aimed to study the effect of uteroplacental circulation restriction on endothelial kidney damage in a fetal rabbit model.

METHODS

New Zealand rabbits were subjected to 40% to 50% of uteroplacental artery ligation at day 25 of pregnancy. After 5 days, surviving fetuses were harvested by cesarean section. The gene and protein expressions of selected enzymes associated with nitric oxide production and oxidative stress were analyzed in fetal kidney homogenates.

RESULTS

The placenta weight (6.06 ± 0.27, p < 0.0319) and fetal body (19.90 ± 1.03, p < 0.0001) were significantly reduced in the uteroplacental circulation restriction group. The kidneys from restricted fetuses presented a mild vascular congestion and glomerular capillary congestion, without inflammation or hypertrophy. We found endothelial nitric oxide synthase phosphorylation inhibition (0.23 ± 0.13, p < 0.012) and arginase-2 (0.29 ± 0.14, p < 0.023) protein induction in fetal kidneys of the circulation restriction group. Finally, the kidneys from circulation-restricted fetuses showed increased inducible nitric oxide synthase messenger RNA (mRNA) (2.68 ± 0.24, p < 0.01) and reduced heme oxygenase-1 mRNA (23 ± 1.3, p < 0.003), with increased reactive oxygen species (1.69 ± 0.09, p < 0.001) and nitrotyrosine protein (1.74 ± 0.28, p < 0.003) levels, without changes in Nox mRNA.

CONCLUSION

We describe significant deregulation of vascular activity and oxidative damage in kidneys of fetal rabbits that have been exposed to restriction of the uterine circulation. © 2016 John Wiley & Sons, Ltd.

[Molecular analysis of sporadic colon cancer]

BACKGROUND

In Chile, colorectal cancer (CRC) is often diagnosed in late stages. Thus, surgical treatment must be complemented with chemotherapy. KRAS mutations and microsatellite instability have been detected in these tumors. However, the response to treatment in patients without KRAS mutations varies and requires a better understanding.

AIM

To determine the frequency and distribution of somatic point mutations in KRAS, BRAF and PIK3CA genes and microsatellite instability status (MSI) in patients with colon cancer (CC).

MATERIAL AND METHODS

A prospective observational study of patients undergoing surgery for colon cancer. Tumor-derived DNA was analyzed by polymerase chain reaction (PCR) for the most frequent mutations of KRAS, BRAF and PIK3CA. PCR was also used to analyze MSI.

RESULTS

Fifty-eight patients with sporadic CC were analyzed, 16 showed KRAS mutations (G12R, G12D, G12V, G13D) and out of the 42 patients that did not show any mutation, 10 had mutations in BRAF (V600E) and PIK3CA (E542K, E545D, E545K, Q546E, H1047R). BRAF mutations alone or in combination with PIK3CA mutations were observed in 27% of high MSI tumors and in 2% of tumors without instability (p < 0.049). A higher percentage of high MSI tumors were located in the right colon (p < 0.001), and showed BRAF mutation (p < 0.020).

CONCLUSIONS

The highest percentage of high MSI and BRAF mutations was observed in the right colon. Therefore, this study suggests the presence of different molecular features between right and left colon tumors that should be considered when defining the therapeutic management.

Combination therapy of menstrual derived mesenchymal stem cells and antibiotics ameliorates survival in sepsis

INTRODUCTION

Sepsis is a clinical syndrome associated with a severe systemic inflammation induced by infection. Although different anti-microbial drugs have been used as treatments, morbidity and mortality rates remain high. Mesenchymal stem cells (MSCs) derived from the bone marrow have demonstrated a partial protective effect in sepsis. Menstrual derived MSCs (MenSCs) emerge as an attractive candidate because they present important advantages over other sources, including improved proliferation rates and paracrine response under specific stress conditions. Here, we evaluate their therapeutic effect in a polymicrobial severe sepsis model.

METHODS

The antimicrobial activity of MenSCs was determined in vitro through direct and indirect bacterial growth assays and the measurement of the expression levels of different antimicrobial peptides (AMPs) by quantitative reverse transcription-polymerase chain reaction. The therapeutic effect of MenSCs was determined in the cecal ligation and puncture (CLP) mouse model. Mice were then treated with antibiotics (AB) or MenSCs alone or in combination. The survival rates and histological and biochemical parameters were evaluated, and the systemic levels of pro- and anti-inflammatory cytokines as well as the response of specific lymphocyte subsets were determined by flow cytometry.

RESULTS

MenSCs exerted an important antimicrobial effect in vitro, mediated by a higher expression of the AMP-hepcidin. In the CLP mouse model, MenSCs in synergy with AB (a) improved the survival rate (95 %) in comparison with saline (6 %), AB (73 %), and MenSCs alone (48 %) groups; (b) enhanced bacterial clearance in the peritoneal fluids and blood; (c) reduced organ injuries evaluated by lower concentrations of the liver enzymes alanine aminotransferase and aspartate aminotransferase; and (d) modulated the inflammatory response through reduction of pro- and anti-inflammatory cytokines without significant loss of T and B lymphocytes.

CONCLUSIONS

We conclude that MenSCs in combination with AB enhance survival in CLP-induced sepsis by acting on multiples targets. MenSCs thus constitute a feasible approach for the future clinical treatment of sepsis.

[Recommendations of the Chilean Association for Digestive Endoscopy for the management of gastric pre-malignant lesions]

An expert panel analyzed the available evidence and reached a consensus to release 24 recommendations for primary and secondary prevention of gastric cancer (CG) in symptomatic patients, with indication for upper GI endoscopy. The main recommendations include (1) Search for and eradicate H. pylori infection in all cases. (2) Systematic gastric biopsies (Sydney protocol) in all patients over 40 years of age or first grade relatives of patient with CG, to detect gastric atrophy, intestinal metaplasia or dysplasia. (3) Incorporate the OLGA system (Operative Link on Gastritis Assessment) to the pathological report, to categorize the individual risk of CG. (4) Schedule endoscopic follow-up according to the estimated risk of CG, namely annual for OLGA III- IV, every 3 years for OLGA I- II or persistent H. pylori infection, every 5 years for CG relatives without other risk factors and no follow-up for OLGA 0, H. pylori (-). (4) Establish basic human and material resources for endoscopic follow-up programs, including some essential administrative processes, and (5) Suggest the early CG/total CG diagnosis ratio of each institution and the proportion of systematic recording of endoscopic images, as quality indicators. These measures are applicable using currently available resources, they can complement any future screening programs for asymptomatic population and may contribute to improve the prognosis of CG in high-risk populations.

Abstract 2230: Gene mutations and deletions inactivates PTEN tumor suppressor in Chilean colon cancer patients

Introduction. Tumor suppressor PTEN acts as a negative regulator of the PI3K/AKT/mTOR pathway, thus controlling cell survival and proliferation. Mutations or deletions inactivating PTEN function lead to over-activation of the PI3K/AKT/mTOR pathway in cancer. PTEN gene alterations have been described in different types of tumors. In colon cancer these mutations range from 1% to 29% of the cases. The aim of this study was to determine the prevalence of PTEN mutations and/or deletions in Chilean colon cancer patients. Methods: ninety-one colon cancer patients were recruited for this study. Genomic DNA from normal and tumor tissue was obtained, and the deletion of PTEN locus was determined by PCR amplification of three STR markers flanking PTEN, and two intragenic markers. To search point mutations we amplified exons 7 and 8 by PCR, and sequenced. PTEN expression was evaluated through immunohistochemistry. Results: We observed deletion events in 9.8% (9/91) of tumors, and inactivating mutations in 5.5% (5/91). Two tumors presented a deletion in one allele and a mutation in the other. Immunohistochemistry detected a very weak expression of PTEN in 55/76 tumors. Conclusions: 15.4 % (12/91) of tumors have PTEN gene inactivated. We observed that deletion was a frequent mechanism for PTEN inactivation in Chilean colon cancer patients.

Note: This abstract was not presented at the meeting.

Citation Format: Gonzalo Encina, Karin Alvarez, Paulina Orellana, Ana María Wielandt, Cynthia Villarroel, Daniela Simian, Luis Contreras, Udo Kronberg, Francisco López, Pilar Carvallo. Gene mutations and deletions inactivates PTEN tumor suppressor in Chilean colon cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2230. doi:10.1158/1538-7445.AM2014-2230

Low plasma fibrinogen levels and blood product transfusion in liver transplantation

BACKGROUND

Risk of bleeding in liver transplantation is determined by surgical technique, preoperative hemoglobin and antifibrinolitic therapy. We hypothesized that keeping these confounders factors identical, preoperative plasma fibrinogen level of ≤2 g/L influenced on blood product requirements.

METHODS

Adult patients underwent orthotropic liver transplantation (LT) during the period between January 1998 and December 2009. Cases were selected according to a propensity matching analysis meeting the following criteria: surgical vena cava preservation, tranexamic acid administration and hemoglobin range between 90 to 120 g/L. Intraoperative management was protocolized. The main variable was the percentage of patients that did not require red blood cells (RBC's).

RESULTS

Six hundred sixty-four patients with LT, 208 excluded, 266 who cannot be matched, the analysis was performed on 190 patients. Two cohorts: Low fibrinogen (≤2 g/L) (61 cases) and standard fibrinogen (>2 g/L) (129 cases) were analyzed. Preoperative platelet count (73.5±52 vs. 104±65; 103/mm3) was different in contrast to the hemoglobin (104.2±8.6 vs. 105.6±8.3; g/L). Use of RBC's resulted significantly higher in the low fibrinogen group (median, 3 vs. 2). The number of patients with no blood product requirements was fewer in the low fibrinogen group (8 cases, 13% vs. 45 cases, 35%). The critical level of plasma fibrinogen (1 g/L) was reached after graft reperfusion in 7 cases (5.5%) in the standard fibrinogen group vs. 24 cases (39%) in the low fibrinogen group.

CONCLUSION

Our data suggest that preoperative plasma fibrinogen level of ≤2 g/L increases requirements for blood products during the surgical procedure of liver transplantation.

[Renal biopsies during the second trimester of pregnancy: report of two cases]

Kidney biopsies were performed in two women during their 21st and 24th week of pregnancy. The first patient developed an abrupt nephrotic syndrome without hypertension or kidney failure. The pathological study disclosed diffuse podocyte alterations such as those observed in focal and segmental glomerulosclerosis, which had a good response to steroidal treatment. The second patient had a progressive renal failure associated with non-nephrotic proteinuria. The biopsy disclosed a fibrillary glomerulopathy.

[Lynch syndrome: selection of families by microsatellite instability and immunohistochemistry]

BACKGROUND

Selection of patients with Lynch Syndrome (LS) for a genetic study involves the application of clinical criteria. To increase the rate of identification of mutations, the use of molecular studies as Microsatellite Instability (MSI) and Immunohistochemistry (IHC) in the tumor has been proposed.

AIM

To demonstrate the usefulness of MSI and IHC in the detection of mutations in patients with LS.

MATERIAL AND METHODS

From our Familial Colorectal Cancer Registry, families suspected of LS were selected according to Amsterdam or Bethesda clinical criteria. Screening of germline mutations of MLH1, MSH2 and MSH6 genes was performed. In addition, analysis of MSI and IHC were performed in colorectal tumors.

RESULTS

A total of 35 families were studied (19 met Amsterdam and 16 met Bethesda criteria). Twenty one families harbored a germline alteration in MLH1, MSH2 or MSH6 (18 Amsterdam and 3 Bethesda). In these families, eighteen different alterations were found, 15 of which were mutations and 3 corresponded to variants of uncertain pathogenicity. On the other hand, 80% of the tumors showed positive microsatellite instability (27 MSI-high and 1 MSI-low), and immunohistochemical testing showed that 77% of tumors had the loss of a protein. Correlation between results of tumor molecular studies and the finding of germline nucleotide change showed that IHC and MSI predicted mutations in 81 and 100% of patients, respectively.

CONCLUSIONS

MSI and IHC can efficiently select patients with a high probability of carrying a mutation in DNA repair genes.

[A screening program for colorectal cancer in Chilean subjects aged fifty years or more]

BACKGROUND

Mortality from colorectal cancer (CCR) in Chile has nearly doubled over the past 15 years. International studies have shown that CCR screening programs based on fecal occult blood test (FOBT) reduce CCR mortality.

AIM

To analyze the results from a CCR screening model in people over 50 years.

MATERIAL AND METHODS

Between 2007 and 2009, a prospective multicenter study was performed in seven major Chilean cities. FOBT using an immunological method, was measured in asymptomatic subjects aged 50 years or more, without risk factors. In patients with a positive FOBT, with symptoms or with family risk factors, a colonoscopy was indicated.

RESULTS

A total of 6348 subjects were assessed, FOBT was performed in 4938 of them, with a compliance of 77%. The result was positive in 9.6%. A total of 2359 colonoscopies were ordered, with an overall compliance of 50.1%. Of the 1184 colonoscopies performed, adenomas and high risk adenomas were found in 304 (26%) and 75 (6%) patients, respectively. Thirteen patients were diagnosed with stage I and IICCR. Three of these lesions were excised endoscopically and 10 surgically. The detection rate of polyps, high risk adenomas and cancer was 75, 12 and 2 per 1000 screened individuals, respectively.

CONCLUSIONS

This program allowed the early detection of an important number of high risk colon lesions, and all patients with CCR were diagnosed at early stages.

Coagulopathy management in liver transplantation

Risk of bleeding and transfusion in liver transplantation is determined by age, severity of liver disease, as well as hemoglobin and plasma fibrinogen values. During the hepatectomy and the anhepatic phase, the coagulopathy is related to a decrease in clotting factors caused by surgical bleeding, facilitated by the increased portal hypertension and esophageal-gastric venous distension. Corrections of hematologic disturbances by administration of large volumes of crystalloid, colloid, or blood products may worsen the coagulopathy. Also, impaired clearance of fibrinolytic enzymes released from damaged cells can lead to primary fibrinolysis. At time of graft reperfusion further deterioration may occur as characterized by global reduction among all coagulation factors, decreased plasminogen activator inhibitor factors, and simultaneous generation of tissue plasminogen activator. In situations with inherent risk of bleeding, hypofibrinogenemia must be corrected. Concern about unwanted events is a major limitation of preventive therapy. There is some evidence for the efficacy of antifibrinolytic drugs to reduce red blood cell requirements. A guide for antifibrinolytic therapy are clot firmness in trhomboelastometry or alternatively, diffuse bleeding associated to a fibrinogen value less than 1 g/L. Because thrombin generation is limited in severe thrombocytopenia, platelet administration is recommended when active bleeding coexists with a platelet count below 50,000/mm(3). When the administration of hemoderivates and antifibrinolytic drugs does not correct severe bleeding, consumption coagulopathy and secondary fibrinolysis should be suspected. Treatment of affected patients should be based upon correcting the underlying cause, mostly related to tissue hypoxia due to critical hypoperfusion.

Collaboration between HPMC and NaCMC in order to reach the polymer critical point in theophylline hydrophilic matrices

Percolation theory has been applied in order to study the existence of critical points as well as the possibility to find a “combined percolation threshold” for ternary hydrophilic matrices prepared with HPMC, NaCMC, and theophylline. For this purpose, different batches of ternary as well as binary hydrophilic matrices have been prepared. Critical points have been found for binary hydrophilic matrices between 21.5 and 31.3% (v/v) of HPMC and between 39 and 54% (v/v) of NaCMC, respectively. In a previous work carried out with the same polymers but a much more soluble drug (KCl), it was demonstrated the existence of a partial collaboration between the polymers in order to establish the gel layer. In this work, it has been observed for the first time the need of a minimum concentration of one of the matrix-forming polymer (between 10 and 20% v/v, approximately) for establishing an effective collaboration.

Abstract 5551: Somatic mutations in KRAS, BRAF and PIK3CA genes in Chilean patients with sporadic colorectal cancer: Correlation with clinical and histological features

Background: KRAS, BRAF and PIK3CA proto-oncogenes encode for proteins involved in epidermal growth factor receptor (EGFR) signaling pathways. Activating mutations in these genes may contribute to tumor development and induce resistance to biological therapies in patients with metastatic colorectal cancer (CRC). Furthermore, microsatellite instability (MSI) has been proposed as a prognostic and predictive marker in sporadic CRC. Patients and methods: In tumors of patients undergoing surgery for sporadic CRC at our institution, somatic mutations in KRAS, BRAF and PIK3CA genes were assessed by single-strand conformation polymorphism(SSCP) and direct sequencing. MSI analysis was performed using the 5 markers of the standard NIH panel. Clinical and histopathological data of the patients were obtained from our prospectively maintained database. Results: A total of 58 patients with a nearly equal gender distribution and a mean age of 62 years were included. A total of 31 mutations in 26 patients were identified. The frequency of mutations was 28% for KRAS, 9% for BRAF and 17% for PIK3CA. No difference was found in the mutation frecuency between the different tumor locations (42,1% in right colon vs. 46,2% in left colon/rectum, P= NS) or lymphnode status (37,5% in node positive vs. 50% in node negative tumors, P=0,346). Tumors with deeper invasion showed a higher frecuency of mutations, but this tendency did not reach statistical significance (32% in pT1-2 vs. 51% in pT3-4, P=0,157). In 26% of the patients, MSI-high was observed, more frecuently in tumors of the right colon (57,9% vs 10,3%, P&lt;0,001). Patients with BRAF mutations, a higher proportion of MSI-high was found compared to BRAF wildtype (27% vs. 2,3%, P=0,013). There was no correlation between the lymphnode positivity and MSI status. Conclusion: Our results show that the frequency of mutations in patients with sporadic CRC in Chile is similar to that described in other countries. The presence of MSI-high is correlated with tumors in the right colon and with mutations in the BRAF gene. The tendency of finding more mutations in locally advanced and node-negative tumors needs to be confirmed in future studies with a larger number of patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5551. doi:1538-7445.AM2012-5551

Alloantigen-specific response is preserved and autoimmunity is maintained in an HIV-positive patient with immunoglobulin A nephropathy undergoing renal transplantation: a warning about long-term reduction in immunosuppression--a case report

We report the case of a 43-year-old patient with HIV infection treated with antiretroviral therapy, which was complicated by immunoglobulin A (IgA) nephropathy and renal failure, who subsequently was transplanted using a deceased donor kidney transplant. During the late posttransplant period we detected specific anti-donor HLA antibodies showing a preserved alloantigen response. A renal biopsy showed no acute cellular or humoral rejection, an absence of pericapillary C4d deposits or SV40 infected cells, but demonstrated IgA mesangial deposits and mild interstitial fibrosis probably related to calcineurin inhibitor toxicity. This case shows that allo- and autoimmune responses are preserved despite immunosuppressive treatment and original HIV disease. It warns of the importance of maintaining optimal monitoring and immunosuppressive strategies among HIV-positive recipients who become solid organ transplant recipients.

Acute and fulminant hepatitis induced by flutamide: case series report and review of the literature

Flutamide is a non-steroidal anti-androgenic drug, commonly used in the treatment of advanced prostate cancer, acne and hirsutism. This drug may induce various degrees of liver injury, including acute liver failure (ALF), with further need for liver transplantation. Here, we present a report of 10 consecutive patients seen in a period of 14 years, with acute liver toxicity induced by flutamide (in most cases severe hepatotoxicity): 3 men and 7 women, with a mean age of 75 and 29 years old, respectively. All men received flutamide as treatment of advanced prostate carcinoma and they developed hepatotoxicity without ALF, and three months after withdrawal of the drug, they recovered completely. In contrast, in 7 young female with liver toxicity caused by flutamide as treatment of various hyperandrogenic conditions (acne and hirsutism), ALF was observed in 5 patients, all of them requiring urgent liver transplantation, with excellent outcome and survival in 4 of them. Based on the above, we believe that flutamide treatment should be preferentially avoided in young female patients with benign pathologies, or if it is used, patients should be warned of its potential severe complications. Also, serial liver tests should be closely monitored and, in case of elevations, the drug should be immediately withdrawn.

Abstract 2229: Detection of somatic mutations in KRAS gene in Chilean patients with advanced colorectal cancer

Introduction: At present, the application of tailored oncologic therapies requires previous performance of mutational analysis of certain genes. In patients with advanced colorectal cancer (CRC), it is essential to detect the presence of activating mutations in the KRAS gene to predict the effectiveness of certain treatments.

Purpose: To determine the presence of KRAS mutations in Chilean patients with advanced CRC, and correlate the mutational status with clinical-pathological data.

Methods: Between October 2009 and August 2010, we prospectively studied the presence of somatic mutations in the KRAS gene in codons 12 and 13 in biopsies of patients with advanced colorectal cancer by allele specific and real time PCR kit. The results were registered in a database, along with the pathology results and clinical data of the patients. Statistical analysis was performed by Student T test and Chi-square test. A p&gt;0.05 was no significant.

Results: A total of 123 patients were analyzed, with a mean age of 61 years and male predominance (60%). Mutations were detected in 47 (39%) of them and only in 2 cases the study was inconclusive. The distribution of the different mutations was as follows: 12Asp (32%), 12Val (26%), 13Asp (19%), 12Cys (11%), 12Ala (6%) and 12Ser (6%). Separated by gender, the detection rate was higher in male patients (45% vs 30%) (p=0.59). Analyzing the data by location of tumor, we found that mutations in right colon tumors was present in 26% (6/23), whereas tumors of the left colon and sigmoid were 43% (16/37) (p=0.1). Mutations detected in patients with lymph node metastasis was 42% comparing to node-negative patients (32%) (p=0.3). In patients with poorly differentiated tumors we found 50% mutations compared to well differentiated (18%) (p=0.08). Finally, the mortality was similar when we compared between WT and mutations patients.

Conclusions: In Chile, 39% of patients with advanced CRC carry mutations in KRAS gene. This result is similar to that described in other populations. There is a tendency to a higher mutation rate in males, patients with left colon cancer, poorly differentiated tumors and patients with lymph nodal involvement.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2229. doi:10.1158/1538-7445.AM2011-2229

[Clinical, electrophysiological and molecular study of 26 chilean patients with spinal muscular atrophy]

BACKGROUND

Spinal Muscular Atrophy (SMA) is an autosomal recessive disorder affecting the anterior horn cells of the spinal cord resulting in muscle weakness and atrophy, linked to the homozygous disruption of the survival motor neuron 1 (SMN1) gene. It is the leading genetic cause of infant death. It has been classified into three types based on the severity of symptoms. Type I SMA is the most severe form with death within the first 2 years of life. Type II and III SMA patients show intermediate and mild forms of the disorder.

AIM

To describe the clinical and electrophysiological findings of 26 Chilean patients with SMA with molecular confirmation.

PATIENTS AND METHODS

Retrospective multicenter analysis of patients with SMA assessed between 2003 and 2010. The diagnosis was suspected on clinical and electrophysiological criteria. Since 2006 molecular genetics confirmation was implemented in one of our centers.

RESULTS

Twenty-six patients between 2 months and 18 years of age at presentation were analyzed; 15 (58%) were males. SMA I, II and III clinical criteria were observed in 4 (15.4 %), 11 (42.3%) and 11 (42.3%)patients, respectively. All had proximal muscle weakness and atrophy. Electromyography showed features of acute denervation or re-innervation with normal motor and sensory nerve conduction. Nine patients required a muscle biopsy. The genetic confirmation of the disease by PCR technique followed by restriction fragment length polymorphism method disclosed the SMN1 gene deletion in all 26 cases. All patients died secondary to respiratory failure, between eight and 14 months of life.

CONCLUSIONS

An adequate clinical and molecular diagnosis of spinal muscular atrophy will help for a better management of these patients.

[Simultaneous kidney and pancreas transplantation (SKPT) in patients with type 1 diabetes and chronic renal failure: experience in 12 patients in Chile]

BACKGROUND

Simultaneous kidney and pancreas transplantation (SKPT) is the best alternative for end stage renal disease among patients with insulin dependent diabetes mellitus.

AIM

To report our experience with SKPT.

MATERIAL AND METHODS

Retrospective analysis of 12 recipients of SKPT transplanted in one center starting in 1994, with a mean follow-up period of 6.8 years (2-15).

RESULTS

Eleven of 12 recipients were in chronic hemodialysis before SKPT. Mean A, B, DR and HLA mismatch was 4.3. Mean preformed anti HLA antibodies was 3.3 %. Mean cold ischemia times for pancreas and kidney were 6 and 10 hours, respectively. In the first eight cases, the pancreas was drained to the bladder, and in the last four, an enteric drainage was performed. Eleven recipients were induced with antibodies, and maintenance immunosuppression consisted of cyclosporin or tacrolimus plus an antiproliferative agent. Ten year patient survival was 70%. Pancreas and kidney survival, defined by insulin and dialysis independence, were 72 and 73% respectively. Fifty percent of recipients experienced acute graft rejection (cellular or humoral), with good response to treatment except in one case.

CONCLUSIONS

This experience shows that SKPT is associated with an excellent patient survival associated to insulin and dialysis independence in 70% of patients at 10 years.