Generating Groups of Products Using Graph Mining Techniques

AbstractRetail industry has evolved. Nowadays, companies around the world need a better and deeper understanding of their customers. In order to enhance store layout, generate customers groups, offers and personalized recommendations, among others. To accomplish these objectives, it is very important to know which products are related to each other.Classical approaches for clustering products, such as K-means or SOFM, do not work when exist scattered and large amounts of data. Even association rules give results that are difficult to interpret. These facts motivate us to use a novel approach that generates communities of products. One of the main advantages of these communities is that are meaningful and easily interpretable by retail analysts. This approach allows the processing of billions of transaction records within a reasonable time, according to the needs of companies

Postoperative complications and mortality following emergency digestive surgery during the COVID-19 pandemic: A multicenter collaborative retrospective cohort study protocol (COVID-CIR)

Infection with the SARS-CoV-2 virus seems to contribute significantly to increased postoperative complications and mortality after emergency surgical procedures. Additionally, the fear of COVID-19 contagion delays the consultation of patients, resulting in the deterioration of their acute diseases by the time of consultation. In the specific case of urgent digestive surgery patients, both factors significantly worsen the postoperative course and prognosis. Main working hypothesis: infection by COVID-19 increases postoperative 30-day-mortality for any cause in patients submitted to emergency/urgent general or gastrointestinal surgery. Likewise, hospital collapse during the first wave of the COVID-19 pandemic increased 30-day-mortality for any cause. Hence, the main objective of this study is to estimate the cumulative incidence of mortality at 30-days-after-surgery. Secondary objectives are: to estimate the cumulative incidence of postoperative complications and to develop a specific postoperative risk propensity model for COVID-19-infected patients.A multicenter, observational retrospective cohort study (COVID-CIR-study) will be carried out in consecutive patients operated on for urgent digestive pathology. Two cohorts will be defined: the "pandemic" cohort, which will include all patients (classified as COVID-19-positive or -negative) operated on for emergency digestive pathology during the months of March to June 2020; and the "control" cohort, which will include all patients operated on for emergency digestive pathology during the months of March to June 2019. Information will be gathered on demographic characteristics, clinical and analytical parameters, scores on the usual prognostic scales for quality management in a General Surgery service (POSSUM, P-POSSUM and LUCENTUM scores), prognostic factors applicable to all patients, specific prognostic factors for patients infected with SARS-CoV-2, postoperative morbidity and mortality (at 30 and 90 postoperative days). The main objective is to estimate the cumulative incidence of mortality at 30 days after surgery. As secondary objectives, to estimate the cumulative incidence of postoperative complications and to develop a specific postoperative risk propensity model for SARS-CoV-2 infected patients.The protocol (version1.0, April 20th 2020) was approved by the local Institutional Review Board (Ethic-and-Clinical-Investigation-Committee, code PR169/20, date 05/05/20). The study findings will be submitted to peer-reviewed journals and presented at relevant national and international scientific meetings.ClinicalTrials.gov Identifier: NCT04479150 (July 21, 2020)

Bayesian analysis of the ICAT·COVID randomized clinical trial

This communication provides new effect measures in the multiplicative scale from the ICAT·COVID randomized clinical trial, obtained through Bayesian statistics. These could not be calculated using the traditional frequentist statistics included in the original publication because the benefits of icatibant (a competitive antagonist of the bradykinin B2 receptors) on top of standard care in patients with COVID-19 pneumonia were such that there were no events in the active group.1 Additive effect measures (eg, risk differences) are the most appropriate measures for identifying the population groups that will benefit most from interventions in presence of interactions acting as effect modifiers.2 However, an aspect that multiplicative measures provide where additive effect measures cannot, is an indication of how many times interventions or exposures increase or decrease disease risk (eg, risk ratio, hazard ratio). Furthermore, multiplicative measures are more commonly used in epidemiology, and are more appropriate for outcome measures with strictly positive values, such as counts and the numerators of incidence rates

Prevalence of HPV-DNA and E6 mRNA in lung cancer of HIV-infected patients

HIV-infected individuals could be at a greater risk for developing lung cancer than the general population due to the higher prevalence in the former of human papillomavirus (HPV) in the oral cavity and higher smoking rates. Our aim was to assess HPV prevalence and E6 viral oncogene transcription in lung cancer samples from HIV-infected individuals. This was a single-center, retrospective study of a cohort of HIV-1-infected patients diagnosed with and treated for lung cancer. Pathological lung samples archived as smears or formalin-fixed paraffin-embedded blocks were subjected to HPV genotyping, detection of human p16 protein and assessment for HPV E6 mRNA expression. Lung cancer samples from 41 patients were studied, including squamous cell carcinoma (32%), adenocarcinoma (34%), non-small cell cancer (27%), and small cell cancer (7%). HPV DNA was detected in 23 out of 41 (56%, 95% CI 41-70%) of samples and high-risk (HR)-HPV types were detected in 16 out of 41 (39%, 95% CI 26-54%), HPV-16 being the most prevalent [13/16 (81.3%, 95% CI 57.0-93%]. In samples with sufficient material left: expression of p16 was detected in 3 out of 10 (30%) of HR-HPV DNA-positive tumors and in 3 out of 7 (43%) of the negative ones; and E6 mRNA was detected in 2 out of 10 (20%) of HPV-16-positive samples (squamous lung cancers). These two patients had a background of a previous HPV-related neoplasia and smoking. HR-HPV DNA detection was prevalent in lung cancers in HIV-infected patients. However, viral oncogene expression was limited to patients with previous HPV-related cancers

El aula como sistema complejo: hacia una formalización de la organización de la vida del aula

Moving towards a concept of education that connotes and defines the educational from the dynamics exhibited by the organization of learning in the classroom requires the use of the sciences of complexity. Assuming the theory of non-linear dynamical systems to understand the phenomena of learning interactions as a history of molecular, sensory and relational coherence is the great challenge of the cognitive sciences. The present study makes a theoretical-empirical review of studies in dynamic systems based on describing the organization of living beings, human life and classroom life. It is proposed that the classroom is a complex system of learning interactions where the semiotic mediation acts as linguistic homeostasis determining the future of the system. In particular, fuzzy set theory is proposed as a mathematical tool of non-linear dynamics to formalize the organization of learning in the classroom.Avanzar hacia un concepto de educación que connote y defina lo educativo a partir de la dinámica que exhibe la organización del aprendizaje en el aula requiere del uso las ciencias de la complejidad. Asumir la teoría de sistemas dinámicos no-lineales para comprender los fenómenos de interacciones de aprendizaje como una historia de coherencias moleculares, sensoriales y relacionales es el gran desafío de las ciencias cognitivas. El presente estudio realiza una revisión teórica-empírica respecto a estudios en sistemas dinámicos basados en describir la organización de los seres vivos, la vida humana y la vida en el aula. Se propone que el aula es un sistema complejo de interacciones de aprendizaje donde la mediación semiótica actúa como homeostasis lingüística determinando el devenir del sistema. Particularmente se propone a la teoría fuzzy set como herramienta matemática de dinámica no-lineal para formalizar la organización del aprendizaje en el aula.

Predictive factors for resection and survival in type A borderline resectable pancreatic ductal adenocarcinoma patients after neoadjuvant therapy: A retrospective cohort study

Introduction:Pancreatic cancer is the seventh leading cause of cancer-related death worldwide, and surgical resection with radical intent remains the only potentially curative treatment option today. However, borderline resectable pancreatic ductal adenocarcinomas (BR-PDAC) stand in the gray area between the resectable and unresectable disease since they are technically resectable but have a high probability of incomplete exeresis. Neoadjuvant treatment (NAT) plays an important role in ensuring resection success.Different survival prognostic factors for BR-PDAC have been well described, but evidence on the predictive factors associated with resection after NAT is scarce. This study aims to study if CA 19-9 plasmatic levels and the tumor anatomical relationship with neighboring vascular structures are prognostic factors for resection and survival (both Overall Survival and Progression-Free Survival) in patients with type A BR-PDAC. Methods:This will be a retrospective cohort study using data from type A BR-PDAC patients who received NAT in the Bellvitge University Hospital. The observation period is from January 2010 until December 2019; patients must have a minimum 12-month follow-up. Patients will be classified according to the MD Anderson Cancer Center criteria for BR-PDAC. Discussion:Patients with BR-PDAC have a high risk for a margin-positive resection. Serum Carbohydrate Antigen 19-9 plasmatic levels and vascular involvement stand out as disease-related prognostic factors.This study will provide valuable information on the prognostic factors associated with resection. We will exclude locally advanced tumors and expect this approach to provide more realistic resection rates without selecting those patients that undergo surgical exploration. However, focusing on an anatomical definition may limit the results' generalizability

SPECT-CT metabolic and morphological study of 2 types of cemented hip stem prostheses in primary total hip arthroplasty patients

Background: Cemented hip arthroplasty requires applying a layer of polymethylmethacrylate (cement) in the space between the bone and the prosthetic stem. This can be achieved using 2 techniques: the thick-layer technique (requires a layer of at least 2 mm to surround an undersized prosthetic stem), and the thin-layer technique (requires a thin layer of cement, so that the prosthetic stem fills the femoral medullary canal). Both approaches have excellent long-term clinical and radiological outcomes, although an implant's insertion into the bone generates inevitable bone mass and bone metabolic changes around it. Combination of single photon emission computed tomography and computed tomography scan (SPECT-CT) imaging combines the single photon emission computed tomography's ability to provide detailed bone metabolism assessment with the computed tomography scan's capacity to provide a meticulous anatomical study. Methods: This is a single center, open label, randomized clinical trial, performed in the premises of the Bellvitge University Hospital. Participants will be randomly assigned to the Thick-layer technique group (Exeter V40 Cemented Femoral Stem) or to the French paradox technique group (Müller Straight Stem). All participants will have a SPECT-CT scan study at 3, 6, 12, and 24 months after the surgery. Discussion: Surgical distress itself and the implant's insertion into the bone may cause microvascular changes that alter periprosthetic bone mass and bone metabolism. To the best of our knowledge, there are no studies using SPECT-CT to compare bone metabolism evolution in the postoperative period between these 2 surgical cementation techniques. We aim to provide information in this regard that could help decision making in complicated implant cases and, maybe, pave the way for larger, and methodologically improved studies

Hypoalbuminemia and advanced age are risk factors for delayed gastric emptying after pancreaticoduodenectomy

Background:delayed gastric emptying (DGE) is one of the most common complications after pancreatoduodenectomy. It could be related to some baseline patient-related characteristics. This study aims to assess the predictive factors associated to DGE in the cohort of patients included in the PAUDA clinical trial. Methods:this study was a retrospective analysis based on the 80 patients included in a randomized clinical trial conducted and published by our group. A descriptive analysis and a bivariate regression model were carried out. Some factors were further scrutinized for associations using the Pearson correlation coefficient and, finally, a multiple regression model using a stepwise selection of variables was conducted. Results:DGE was diagnosed in 36 (45 %) out of 80 patients (DGE group). The number of patients older than 60 years old in the DGE group was greater than in the group without DGE (32 vs 28 patients, p = 0.009]). Likewise, the number of patients with a preoperative albumin 200 & mu;mol/L (14 vs 8 patients, p = 0.039); postoperative haemorrhage (7 vs 1 patients, p = 0.011); postoperative intraabdominal abscess (12 vs 5 patients, p = 0.017); and postoperative biliary fistula (5 vs 0 patients, p = 0.011), was also greater in the DGE group. Two risk factors were associated with DGE: the patient's age at the time of surgery and preoperative hypoalbuminemia (serum albumin concentration & LE; 35g/L). Conclusions:the patient's age at the time of surgery and the preoperative nutritional status are independent risk factors to the development of DGE after pancreatoduodenectomy

Prevalence of HPV-DNA and E6 mRNA in lung cancer of HIV-infected patients

HIV-infected individuals could be at a greater risk for developing lung cancer than the general population due to the higher prevalence in the former of human papillomavirus (HPV) in the oral cavity and higher smoking rates. Our aim was to assess HPV prevalence and E6 viral oncogene transcription in lung cancer samples from HIV-infected individuals. This was a single-center, retrospective study of a cohort of HIV-1-infected patients diagnosed with and treated for lung cancer. Pathological lung samples archived as smears or formalin-fixed paraffin-embedded blocks were subjected to HPV genotyping, detection of human p16 protein and assessment for HPV E6 mRNA expression. Lung cancer samples from 41 patients were studied, including squamous cell carcinoma (32%), adenocarcinoma (34%), non-small cell cancer (27%), and small cell cancer (7%). HPV DNA was detected in 23 out of 41 (56%, 95% CI 41-70%) of samples and high-risk (HR)-HPV types were detected in 16 out of 41 (39%, 95% CI 26-54%), HPV-16 being the most prevalent [13/16 (81.3%, 95% CI 57.0-93%]. In samples with sufficient material left: expression of p16 was detected in 3 out of 10 (30%) of HR-HPV DNA-positive tumors and in 3 out of 7 (43%) of the negative ones; and E6 mRNA was detected in 2 out of 10 (20%) of HPV-16-positive samples (squamous lung cancers). These two patients had a background of a previous HPV-related neoplasia and smoking. HR-HPV DNA detection was prevalent in lung cancers in HIV-infected patients. However, viral oncogene expression was limited to patients with previous HPV-related cancers

Are iodophor-impregnated drapes associated with lower intraoperative contamination compared to no adhesive drape?: A protocol for systematic review and meta analysis

Background:Surgical site infection (SSI) is one of the most frightening complications after surgery. Adhesive drapes (AD) are widely used as an infection prevention tool. They can be non-impregnated or iodophor-impregnated, although non-impregnated are less used as they might be related to higher number of infections. One of the most common ways to study their efficacy is by analyzing the intraoperative contamination, which is a useful primary endpoint as it does not need follow-up and it has been strongly associated with infections. Therefore, we believe a systematic review (SR) and meta-analysis is needed to determine which is the literature available about this topic and to explore their results. Methods:All randomized controlled trials (RCT) published since 1984 through to January 15, 2023 will be included. Non-human and experimental studies will be excluded. We will only include studies written in English. We will conduct searches in the following electronic databases: MEDLINE (via PubMed), SCOPUS and Web Of Science. The protocol of the SR was registered in PROSPERO under the number CRD42023391651 and was written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol guidelines. Discussion:The evidence regarding the benefits of using iodophor-impregnated adhesive drapes (IIAD) is scarce. Therefore, this SR and meta-analysis is required to determine if they are related with a lower intraoperative contamination incidence, compared to no AD