Evaluation of genetic variants associated with the risk of thiopurine-related pancreatitis: a case control study from ENEIDA registry.

BACKGROUND: Risk factors for developing pancreatitis due to thiopurines in patients with inflammatory bowel disease (IBD) are not clearly identified. AIM: Our aim was to evaluate the predictive pharmacogenetic risk of pancreatitis in IBD patients treated with thiopurines. METHODS: We conducted an observational pharmacogenetic study of acute pancreatitis events in a cohort study of IBD patients treated with thiopurines from the prospectively maintained ENEIDA registry biobank of GETECCU. Samples were obtained and the CASR, CEL, CFTR, CDLN2, CTRC, SPINK1, CPA1, and PRSS1 genes, selected based on their known association with pancreatitis, were fully sequenced. RESULTS: Ninety-five cases and 105 controls were enrolled, 57% were women. Median age at pancreatitis diagnosis was 39 years. We identified 81 benign variants (50 in cases and 67 in controls) and a total of 35 distinct rare pathogenic and unknown significance variants (10 in CEL, 21 in CFTR, 1 in CDLN2, and 3 in CPA1). None of the cases or controls carried pancreatitis-predisposing variants within the CASR, CPA1, PRSS1, and SPINK1 genes, nor a pathogenic CFTR mutation. Four different variants of unknown significance were detected in the CDLN and CPA1 genes; one of them was in the CDLN gene in a single patient with pancreatitis, and 3 in the CPA1 gene in 5 controls. After the analysis of the variants detected, no significant differences were observed between cases and controls. CONCLUSION: In patients with IBD, genes known to cause pancreatitis seem not to be involved in thiopurine-related pancreatitis onset.

Optimizing dense feed-forward neural networks.

Deep learning models have been widely used during the last decade due to their outstanding learning and abstraction capacities. However, one of the main challenges any scientist has to face using deep learning models is to establish the network's architecture. Due to this difficulty, data scientists usually build over complex models and, as a result, most of them result computationally intensive and impose a large memory footprint, generating huge costs, contributing to climate change and hindering their use in computational-limited devices. In this paper, we propose a novel dense feed-forward neural network constructing method based on pruning and transfer learning. Its performance has been thoroughly assessed in classification and regression problems. Without any accuracy loss, our approach can compress the number of parameters by more than 70%. Even further, choosing the pruning parameter carefully, most of the refined models outperform original ones. Furthermore, we have verified that our method not only identifies a better network architecture but also facilitates knowledge transfer between the original and refined models. The results obtained show that our constructing method not only helps in the design of more efficient models but also more effective ones.

Development of a Prediction Model for Short-Term Remission of Patients with Crohn's Disease Treated with Anti-TNF Drugs.

Therapy with anti-tumor necrosis factor (TNF) has dramatically changed the natural history of Crohn's disease (CD). However, these drugs are not without adverse events, and up to 40% of patients could lose efficacy in the long term. We aimed to identify reliable markers of response to anti-TNF drugs in patients with CD. A consecutive cohort of 113 anti-TNF naive patients with CD was stratified according to clinical response as short-term remission (STR) or non-STR (NSTR) at 12 weeks of treatment. We compared the protein expression profiles of plasma samples in a subset of patients from both groups prior to anti-TNF therapy by SWATH proteomics. We identified 18 differentially expressed proteins (p ≤ 0.01, fold change ≥ 2.4) involved in the organization of the cytoskeleton and cell junction, hemostasis/platelet function, carbohydrate metabolism, and immune response as candidate biomarkers of STR. Among them, vinculin was one of the most deregulated proteins (p < 0.001), whose differential expression was confirmed by ELISA (p = 0.054). In the multivariate analysis, plasma vinculin levels along with basal CD Activity Index, corticosteroids induction, and bowel resection were factors predicting NSTR.

The influence of limb role, direction of movement and limb dominance on movement strategies during block jump-landings in volleyball.

The identification of movement strategies in situations that are as ecologically valid as possible is essential for the understanding of lower limb interactions. This study considered the kinetic and kinematic data for the hip, knee and ankle joints from 376 block jump-landings when moving in the dominant and non-dominant directions from fourteen senior national female volleyball players. Two Machine Learning methods were used to generate the models from the dataset, Random Forest and Artificial Neural Networks. In addition, decision trees were used to detect which variables were relevant to discern the limb movement strategies and to provide a meaningful prediction. The results showed statistically significant differences when comparing the movement strategies between limb role (accuracy > 88.0% and > 89.3%, respectively), and when moving in the different directions but performing the same role (accuracy > 92.3% and > 91.2%, respectively). This highlights the importance of considering limb dominance, limb role and direction of movement during block jump-landings in the identification of which biomechanical variables are the most influential in the movement strategies. Moreover, Machine Learning allows the exploration of how the joints of both limbs interact during sporting tasks, which could provide a greater understanding and identification of risky movements and preventative strategies. All these detailed and valuable descriptions could provide relevant information about how to improve the performance of the players and how to plan trainings in order to avoid an overload that could lead to risk of injury. This highlights that, there is a necessity to consider the learning models, in which the spike approach unilaterally is taught before the block approach (bilaterally). Therefore, we support the idea of teaching bilateral approach before learning the spike, in order to improve coordination and to avoid asymmetries between limbs.

Effectiveness and safety of methotrexate monotherapy in patients with Crohn's disease refractory to anti-TNF-α: results from the ENEIDA registry.

BACKGROUND: Methotrexate can be used to maintain remission in Crohn's disease patients who are intolerant to thiopurines. Data on its use as monotherapy in other scenarios are limited. AIM: To assess the effectiveness of methotrexate monotherapy in Crohn's disease patients after previous failure to anti-tumour necrosis factor (anti-TNFα) drugs. METHODS: A retrospective, observational multicentre study of data from the Spanish ENEIDA registry. Participants were patients with active Crohn's disease and previous failure to anti-TNFα started on methotrexate monotherapy. Short-term effectiveness was assessed at 12-16 weeks based on Harvey-Bradshaw index (HBI): clinical remission as HBI ≤ 3 points and clinical response as HBI drop of ≥ 3 points over baseline. Long-term effectiveness was defined as steroid-free methotrexate persistence from 12 to 16 weeks until maximum follow up. Adverse events were recorded. RESULTS: Data were compiled for 110 patients treated with methotrexate after a failed response to one (39%) or two (55.6%) anti-TNFα agents. Short-term clinical response and remission rates were 60% and 30.9% respectively. Of 74 patients who continued after week 16, long-term effectiveness was achieved in 82% and 74% at 12 and 24 months respectively. In the multivariate analysis, non-remission at short term (vs remission) was associated with long-term failure (HR 2.58, 95%CI 1.95-3.68, P = 0.028). Adverse events (evaluated in 100 patients) were recorded in 44%, and in 30.4% of these patients, they led to methotrexate discontinuation. CONCLUSIONS: The benefits observed suggest methotrexate monotherapy could be a valid option in Crohn's disease patients with previous failure to anti-TNFα.

Congenital dyserythropoietic anemia types Ib, II, and III: novel variants in the CDIN1 gene and functional study of a novel variant in the KIF23 gene.

Congenital dyserythropoietic anemias (CDA) are disorders characterized by ineffective erythropoiesis and morphological anomalies in erythrocytes and erythroblasts. The purpose of this study is to identify the gene variants in patients diagnosed with CDA. We analyzed five unrelated patients and two siblings with a targeted panel of genes to CDA: CDAN1, CDIN1, SEC23B, KIF23, KLF1, and GATA1 genes. We found three novel variants in the CDIN1 gene (p.Leu136Val, p.Tyr247Cys, and p.Ile273Thr), four known variants in the SEC23B gene (p.Arg14Trp, p.Arg554Ter, p.Asp239Gly, and p.Ser436Leu), and one novel variant in the KIF23 gene (p.Leu945Trpfs*31). The in silico analysis of novel variants predict that they are pathogenic and, the in vitro study confirms the functional impact of the KIF23 variant on the protein location.

Ability to Predict Side-Out Performance by the Setter's Action Range with First Tempo Availability in Top European Male and Female Teams.

The aims of this study were to compare the Setter's action range with availability of first tempo (SARA) between male and female volleyball; and to determine the relationship between several spatial and offensive variables and their influence in the success of the side-out in male and female volleyball. A total of 1302 side-outs (639 male, 663 female) were registered (2019 European Championship). The ranking, reception efficacy, position and trajectory of the setter between reception and set, first tempo availability, side-out result, rotation, and attack lane were analyzed through Recursive Partitioning for classification, regression and survival tree models and classification and regression trees algorithms. Our results present female teams with more reduced SARAs than male teams, meaning female setters tend to play closer to the net. The correlation between the ranking and the distance from the average position of the setter to the ideal setting zone was not significant. A movement of the setter of 30° or less and more than 1 m in distance might improve the performance of the side-out. Depending on the spatial usage of the setter, some rotations might be more successful than others. When assessing performance, the teams should consider the ability to play quick attacks when their reception is not as precise as they would expect.

Can kinematic and kinetic differences between planned and unplanned volleyball block jump-landings be associated with injury risk factors?

INTRODUCTION: Injury prevention programs for athletes are still limited by a lack of understanding of specific risk factors that can influence injuries within different sports. The majority of studies on volleyball have not considered the movement patterns when moving in different directions or in planned and unplanned block jump-landings. METHODS: This study investigated all planes mechanics between the lead and trail limb when moving in dominant and non-dominant directions, for both planned and unplanned jump-landings in thirteen semi-professional female volleyball players. Ankle, knee and hip joint kinematics, kinetics and joint stiffness were recorded. RESULTS: Our results showed statistically significant differences between the lead limb and the trail limb in the hip flexion angles, moments and velocity; in the knee flexion angles, moments, stiffness, power and energy absorption and in the ankle dorsiflexion, power and energy absorption, showing a tendency where the lead limb has a higher injury risk than the trail limb. When considering planned versus unplanned situations, there were statistically significant differences in knee flexion angles, moments, power and energy absorption; and hip contact angle, flexion angular velocity and energy absorption, with musculoskeletal adaptations in the planned situations. DISCUSSION: It appears that the role of the limb, either lead or trail, is more important than the limb dominance when performing directional jump-landings, with the lead limb having a higher implication on possible overuse injuries than the trail limb. Furthermore, planned movements showed a difference in strategy indicating greater implications to possible overuse injuries than in the unplanned situations which may be associated with more conscious thought about the movements. CONCLUSION: Coaches should consider unilateral coordination training in both landing directions for the lead and trail limb, and should adapt training to replicate the competition environment, using unplanned situations to minimize asymmetries to might reduce injury risks.

The combination of granulocyte-monocyte apheresis and vedolizumab: A new treatment option for ulcerative colitis?

OBJECTIVES: To assess the effectiveness and safety of combining granulocyte-monocyte apheresis (GMA) and vedolizumab (VDZ) in patients with refractory ulcerative colitis (UC). METHODS: This retrospective, multicentre pilot study included all UC patients receiving both GMA and VDZ. We recorded data on GMA sessions, demographic characteristics, and clinical response. Effectiveness was assessed 1 and 6 months after finishing the GMA using the partial Mayo score, C-reactive protein, and fecal calprotectin levels. Data were also compiled on VDZ intensification, use of new immunomodulators and colectomy during follow-up. RESULTS: Eight patients were included (mean age 46 years; 63% female; mean disease duration, 132 months; 50% E3). GMA was started after a loss of response to VDZ in all cases (25% primary nonresponse and 75% secondary loss of response). All had previously received anti-TNF agents. VDZ was prescribed as the second-, third-, or fourth-line biologic in 37%, 50%, and 13% of cases, respectively. Patients had a mean baseline partial Mayo score of 7.5 (SD 2.1) and received a median of 15 GMA sessions (range 5-38). After a median follow-up of 7.5 months (IQR 5-12), partial Mayo score decreased after 1 and 6 months (P = .01 and .06, respectively). Three patients (38%) achieved steroid-free clinical remission and five (63%) withdrew VDZ. Colectomy rate was 38%. No adverse events were observed during the combination therapy. CONCLUSIONS: This small case series suggests that combining GMA with VDZ could be a treatment option in selected cases of UC with an inadequate response to this biologic agent.

Clinical Characteristics, Associated Malignancies and Management of Primary Sclerosing Cholangitis in Inflammatory Bowel Disease Patients: A Multicentre Retrospective Cohort Study.

BACKGROUND AND AIMS: Primary sclerosing cholangitis [PSC] is usually associated with inflammatory bowel disease [IBD]. An increased risk of malignancies, mainly colorectal cancer [CRC] and cholangiocarcinoma [CCA], has been reported in PSC-IBD patients. Our aim was to determine the clinical characteristics and management of PSC in IBD patients, and the factors associated with malignancies. METHODS: PSC-IBD patients were identified from the Spanish ENEIDA registry of GETECCU. Additional data were collected using the AEG-REDCap electronic data capture tool. RESULTS: In total, 277 PSC-IBD patients were included, with an incidence rate of 61 PSC cases per 100 000 IBD patient-years, 69.7% men, 67.5% ulcerative colitis and mean age at PSC diagnosis of 40 ± 16 years. Most patients [85.2%] were treated with ursodeoxycholic acid. Liver transplantation was required in 35 patients [12.6%] after 79 months (interquartile range [IQR] 50-139). It was more common in intra- and extrahepatic PSC compared with small-duct PSC (16.3% vs 3.3%; odds ratio [OR] 5.7: 95% confidence interval [CI] = 1.7-19.3). The incidence rate of CRC since PSC diagnosis was 3.3 cases per 1000 patient-years [95% CI = 1.9-5.6]. Having symptoms of PSC at PSC diagnosis was the only factor related to an increased risk of CRC after IBD diagnosis [hazard ratio= 3.3: 95% CI = 1.1-9.9]. CCA was detected in seven patients [2.5%] with intra- and extrahepatic PSC, with median age of 42 years [IQR 39-53], and presented a lower life expectancy compared with patients without CCA and patients with or without CRC. CONCLUSIONS: PSC-IBD patients with symptoms of PSC at PSC diagnosis have an increased risk of CRC. CCA was only diagnosed in patients with intra- and extrahepatic PSC and was associated with poor survival.

Non-invasive ventilation in obesity hypoventilation syndrome without severe obstructive sleep apnoea.

BACKGROUND: Non-invasive ventilation (NIV) is an effective form of treatment in patients with obesity hypoventilation syndrome (OHS) who have concomitant severe obstructive sleep apnoea (OSA). However, there is a paucity of evidence on the efficacy of NIV in patients with OHS without severe OSA. We performed a multicentre randomised clinical trial to determine the comparative efficacy of NIV versus lifestyle modification (control group) using daytime arterial carbon dioxide tension (PaCO2) as the main outcome measure. METHODS: Between May 2009 and December 2014 we sequentially screened patients with OHS without severe OSA. Participants were randomised to NIV versus lifestyle modification and were followed for 2 months. Arterial blood gas parameters, clinical symptoms, health-related quality of life assessments, polysomnography, spirometry, 6-min walk distance test, blood pressure measurements and healthcare resource utilisation were evaluated. Statistical analysis was performed using intention-to-treat analysis. RESULTS: A total of 365 patients were screened of whom 58 were excluded. Severe OSA was present in 221 and the remaining 86 patients without severe OSA were randomised. NIV led to a significantly larger improvement in PaCO2 of -6 (95% CI -7.7 to -4.2) mm Hg versus -2.8 (95% CI -4.3 to -1.3) mm Hg, (p<0.001) and serum bicarbonate of -3.4 (95% CI -4.5 to -2.3) versus -1 (95% CI -1.7 to -0.2 95% CI)  mmol/L (p<0.001). PaCO2 change adjusted for NIV compliance did not further improve the inter-group statistical significance. Sleepiness, some health-related quality of life assessments and polysomnographic parameters improved significantly more with NIV than with lifestyle modification. Additionally, there was a tendency towards lower healthcare resource utilisation in the NIV group. CONCLUSIONS: NIV is more effective than lifestyle modification in improving daytime PaCO2, sleepiness and polysomnographic parameters. Long-term prospective studies are necessary to determine whether NIV reduces healthcare resource utilisation, cardiovascular events and mortality. TRIAL REGISTRATION NUMBER: NCT01405976; results.

Eficacia a medio y largo plazo de la ventilación no invasiva en el síndrome de hipoventilación-obesidad (estudio Pickwick) / Mid- and Long-Term Efficacy of Non-Invasive Ventilation in Obesity Hypoventilation Syndrome: The Pickwick's Study

El proyecto Pickwick es un estudio prospectivo, aleatorizado, abierto y controlado con grupos en paralelo que intenta dar respuesta a los interrogantes del síndrome de hipoventilación-obesidad (SHO), una enfermedad creciente en los países desarrollados. Para ello, pacientes con SHO fueron divididos en pacientes con índice de apneas-hipoapneas (IAH) ≥30 y <30 mediante polisomnografía. El grupo con IAH≥30 se aleatorizó a tratamiento mediante estilo de vida saludable, ventilación no invasiva (VNI) o presión en la vía aérea positiva continua (CPAP). El grupo con IAH<30, a VNI o estilo de vida saludable. Su objetivo ha sido evaluar la eficacia del tratamiento con ventilación VNI, CPAP y estilo de vida saludable (control) a medio y largo plazo en el SHO, analizando como variable primaria la PaCO2 y los días de hospitalización, respectivamente, y como variables operativas el porcentaje de abandonos por razones médicas y mortalidad. Los objetivos secundarios a medio plazo fueron: 1) evaluar la eficacia clínica-funcional, en calidad de vida, en variables polisomnográficas y ecocardiográficas; 2) investigar la importancia de los episodios apneicos y de la leptina en la génesis de la hipoventilación alveolar diurna y el cambio con los diferentes tratamientos; 3) investigar si las alteraciones metabólicas, bioquímicas y disfunción endotelial vascular dependen de la presencia de apneas e hipoapneas, y 4) cambio de marcadores inflamatorios y de daño endotelial con los tratamientos. Los objetivos secundarios a largo plazo fueron: 1) evaluar la eficacia clínico-funcional y en calidad de vida con VNI y CPAP; 2) cambio de la leptina, marcadores inflamatorios y de daño endotelial con los tratamientos; 3) cambio de la hipertensión pulmonar y otras variables ecocardiográficas, así como en la hipertensión arterial e incidencia de episodios cardiovasculares, y 4) frecuencia de abandonos y mortalidad

The Pickwick project was a prospective, randomized and controlled study, which addressed the issue of obesity hypoventilation syndrome (OHS), a growing problem in developed countries. OHS patients were divided according to apnea-hypopnea index (AHI) ≥ 30 and < 30 determined by polysomnography. The group with AHI ≥ 30 was randomized to intervention with lifestyle changes, noninvasive ventilation (NIV) or continuous positive airway pressure (CPAP); the group with AHI < 30 received NIV or lifestyle changes. The aim of the study was to evaluate the efficacy of NIV treatment, CPAP and lifestyle changes (control) in the medium and long-term management of patients with OHS. The primary variables were PaCO2 and days of hospitalization, and operating variables were the percentage of dropouts for medical reasons and mortality. Secondary medium-term objectives were: (I) to evaluate clinical-functional effectiveness on quality of life, echocardiographic and polysomnographic variables; (II) to investigate the importance of apneic events and leptin in the pathogenesis of daytime alveolar hypoventilation and change according to the different treatments; (III) to investigate whether metabolic, biochemical and vascular endothelial dysfunction disorders depend on the presence of apneas and hypopneasm and (IV) changes in inflammatory markers and endothelial damage according to treatment. Secondary long-term objectives were to evaluate: (I) clinical and functional effectiveness and quality of life with NIV and CPAP; (II) changes in leptin, inflammatory markers and endothelial damage according to treatment; (III) changes in pulmonary hypertension and other echocardiographic variables, as well as blood pressure and incidence of cardiovascular events, and (IV) dropout rate and mortality

Mid- and Long-Term Efficacy of Non-Invasive Ventilation in Obesity Hypoventilation Syndrome: The Pickwick's Study.

The Pickwick project was a prospective, randomized and controlled study, which addressed the issue of obesity hypoventilation syndrome (OHS), a growing problem in developed countries. OHS patients were divided according to apnea-hypopnea index (AHI) ≥30 and <30 determined by polysomnography. The group with AHI≥30 was randomized to intervention with lifestyle changes, noninvasive ventilation (NIV) or continuous positive airway pressure (CPAP); the group with AHI<30 received NIV or lifestyle changes. The aim of the study was to evaluate the efficacy of NIV treatment, CPAP and lifestyle changes (control) in the medium and long-term management of patients with OHS. The primary variables were PaCO2 and days of hospitalization, and operating variables were the percentage of dropouts for medical reasons and mortality. Secondary medium-term objectives were: (i)to evaluate clinical-functional effectiveness on quality of life, echocardiographic and polysomnographic variables; (ii)to investigate the importance of apneic events and leptin in the pathogenesis of daytime alveolar hypoventilation and change according to the different treatments; (ii)to investigate whether metabolic, biochemical and vascular endothelial dysfunction disorders depend on the presence of apneas and hypopneasm and (iv)changes in inflammatory markers and endothelial damage according to treatment. Secondary long-term objectives were to evaluate: (i)clinical and functional effectiveness and quality of life with NIV and CPAP; (ii)changes in leptin, inflammatory markers and endothelial damage according to treatment; (iii)changes in pulmonary hypertension and other echocardiographic variables, as well as blood pressure and incidence of cardiovascular events, and (iv)dropout rate and mortality.

Ocular lesions associated with Chlamydia suis in a wild boar piglet (Sus scrofa) from a semi-free range population in Spain.

The role of the wild boar (Sus scrofa) as a reservoir for a large number of pathogens that can affect both domestic animals and humans has been widely studied in the last few years. However, the impact of some of these pathogens on the health of wild boar populations is still being determined. This article presents a clinical case of severe bilateral keratoconjunctivitis affecting a 2-mo-old piglet from a semi-free range population in Spain. Histopathologic and microbiologic analysis revealed lesions in the cornea, choroid, and optical nerve, and Chlamydia suis was detected in the eyes bilaterally. The visual handicap resulting from this type of lesion greatly affects the survival of this affected piglet.

A zoonotic ringworm outbreak caused by a dysgonic strain of Microsporum canis from stray cats

Antecedentes Los gatos son frecuentemente portadores de Microsporum canis. Los estudiantes de veterinaria están especialmente expuestos a la infección. Objetivos Se describe un brote de tiña zoonótica difundido por una camada de gatos callejeros. Cuatro estudiantes de veterinaria, cuatro perros y seis gatos de cinco localizaciones diferentes se vieron afectados. Todos tuvieron contacto directo o indirecto con la camada de gatitos infectados. Se intenta identificar el dermatofito causal. Métodos Se utilizan los procedimientos micológicos morfológicos y de cultivo convencionales. Resultados Los hallazgos microscópicos en pelo y raspados cutáneos aclarados en KOH al 20% sugirieron fuertemente una etiología por M. canis, y el diagnóstico de tiña fue apoyado empíricamente por el éxito en el tratamiento de humanos y animales. Sin embargo, los cultivos no mostraron la morfología esperada. Conclusiones Los caracteres del cultivo de nuestra cepa son comparados con los descritos por otros autores en cepas disgónicas de M. canis. Las características epidemiológicas son discutidas también(AU)

Background Cats are frequent carriers of Microsporum canis and veterinary students are at high risk of exposure and acquisition of the organism a la infección. Objectives An outbreak of zoonotic ringworm carried by a litter of stray cats is described. Four veterinary students, four dogs, and six cats living in five separate locations were affected. All had direct or indirect contact with the infected kitten litter. We tried to identify the causal dermatophyte. Methods Conventional and mycological culture methods were used. Results Microscopic features of scrapings and hairs treated with 20% KOH strongly suggested a M. canis etiology, and a diagnosis of ringworm was empirically supported by successful treatment of humans and animals. Nevertheless, cultures failed to show the expected morphology. Conclusions Culture features of our strain are compared with those described by other authors for dysgonic M. canis strains. Epidemiological features are also discussed(AU)

A zoonotic ringworm outbreak caused by a dysgonic strain of Microsporum canis from stray cats.

BACKGROUND: Cats are frequent carriers of Microsporum canis and veterinary students are at high risk of exposure and acquisition of the organism a la infección. OBJECTIVES: An outbreak of zoonotic ringworm carried by a litter of stray cats is described. Four veterinary students, four dogs, and six cats living in five separate locations were affected. All had direct or indirect contact with the infected kitten litter. We tried to identify the causal dermatophyte. METHODS: Conventional and mycological culture methods were used. RESULTS: Microscopic features of scrapings and hairs treated with 20% KOH strongly suggested a M. canis etiology, and a diagnosis of ringworm was empirically supported by successful treatment of humans and animals. Nevertheless, cultures failed to show the expected morphology. CONCLUSIONS: Culture features of our strain are compared with those described by other authors for dysgonic M. canis strains. Epidemiological features are also discussed.

Artificial neural network-based equation for estimating VO2max from the 20 m shuttle run test in adolescents.

OBJECTIVE: To develop an artificial neural network (ANN)-equation to estimate maximal oxygen uptake (VO(2max)) from 20m shuttle run test (20 mSRT) performance (stage), sex, age, weight, and height in young persons. METHODS: The 20 mSRT was performed by 193 (122 boys and 71 girls) adolescents aged 13-19 years. All the adolescents wore a portable gas analyzer to measure VO(2) and heart rate during the test. The equation was developed and cross-validated following the ANN mathematical model. The neural net performance was assessed through several error measures. Agreement between the measured VO(2max) and estimated VO(2max) from Léger's and ANN equations were analysed following the Bland and Altman method. RESULTS: The percentage error was 17.13 and 7.38 for Léger and ANN-equation (P<0.001), respectively, and the standard error of the estimate obtained with Léger's equation was 4.27 ml/(kg min), while for the ANN-equation was 2.84 ml/(kg min). A Bland-Altman plot for the measured VO(2max) and Léger-VO(2max) showed a mean difference of 4.9 ml/(kg min) (P<0.001), while the Bland-Altman plot for the measured VO(2max) and ANN-VO(2max) showed a mean difference of 0.5 ml/(kg min) (P=0.654). In the validation sample, the percentage error was 21.08 and 8.68 for Léger and ANN-equation (P<0.001), respectively. CONCLUSIONS: In this study, an ANN-based equation to estimate VO(2max) from 20 mSRT performance (stage), sex, age, weight, and height in adolescents was developed and cross-validated. The newly developed equation was shown to be more accurate than Léger's. The proposed model has been coded in a user-friendly spreadsheet.