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1.
Evol Comput ; : 1-25, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38713737

ABSTRACT

Evolutionary Computation (EC) often throws away learned knowledge as it is reset for each new problem addressed. Conversely, humans can learn from small-scale problems, retain this knowledge (plus functionality) and then successfully reuse them in larger-scale and/or related problems. Linking solutions to problems together has been achieved through layered learning, where an experimenter sets a series of simpler related problems to solve a more complex task. Recent works on Learning Classifier Systems (LCSs) has shown that knowledge reuse through the adoption of Code Fragments, GP-like tree-based programs, is plausible. However, random reuse is inefficient. Thus, the research question is how LCS can adopt a layered-learning framework, such that increasingly complex problems can be solved efficiently? An LCS (named XCSCF*) has been developed to include the required base axioms necessary for learning, refined methods for transfer learning and learning recast as a decomposition into a series of subordinate problems. These subordinate problems can be set as a curriculum by a teacher, but this does not mean that an agent can learn from it. Especially if it only extracts over-fitted knowledge of each problem rather than the underlying scalable patterns and functions. Results show that from a conventional tabula rasa, with only a vague notion of what subordinate problems might be relevant, XCSCF* captures the general logic behind the tested domains and therefore can solve any n-bit Multiplexer, n-bit Carry-one, n-bit Majority-on, and n-bit Even-parity problems. This work demonstrates a step towards continual learning as learned knowledge is effectively reused in subsequent problems.

2.
Article in English | MEDLINE | ID: mdl-36231754

ABSTRACT

Variogram calculation is a fundamental tool for studying ore grade data in mineral deposits. It allows the discovery of hidden structures within the data and preferential directions of mineralization where the geological continuity is longer. The variogram allows us to classify samples and to define both the search radii for interpolation and the use of kriging as an interpolation and resource classification method. It is not difficult to use it in one dimension; complexity increases in two dimensions as the necessity to search for possible grade anisotropies in all directions arises. Three-dimensionally it is even more difficult to try to define the parameters of lag, bandwidth, and tolerances that define the data of the variogram calculation algorithm. There are rules of thumb to help in the development, but a trial-and-error approach is used in order to find enough sample pairs to allow the generation of variograms truly representative of the data. In this paper, two strategies are shown to help in variogram construction, the use of variogram maps and the graphical representation of the pair search areas (cones or pencils). The freeware tool RecMin Variograms has been developed and is freely available for download at its website; it is easy to learn and use. R code based on RGeostats libraries is used to check the operation and results of RecMin Variograms. Applying geostatistics to mineral deposits is essential to know the areas with the highest grades, thus allowing exact planning of future mining exploitation and minimizing mine footprint and environmental impact.


Subject(s)
Geology , Mining , Environment
3.
Pediatr Transplant ; 26(2): e14170, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34656076

ABSTRACT

BACKGROUND: New-onset diabetes after transplantation refers to the development of diabetes after solid organ transplantation without a history of diabetes and is related to poor graft function and lower survival rate. In the kidney transplant population, NODAT occurs in 24% of adults and 9% of children. The real incidence and risk factors in the pediatric population is unknown, which we aimed to determine in this study. METHODS: A retrospective study was conducted in patients who underwent kidney transplantation in the Pediatric Nephrology Service of the "Federico Gómez" Children's Hospital of Mexico. RESULTS: The study included 127 children divided into groups 1 and 2 (without [n = 110 patients, 86.5%] and with NODAT [n = 17 patients, 13.4%], respectively), with median ages of 14 years (interquartile range [IQR], 9-16 years) and 15 years (IQR, 13-16 years; p = .3), respectively. Cox proportional hazards analysis revealed an association between changes from baseline to 24-h postoperative blood glucose level as a risk factor of the development of NODAT. This implies that each unit increase in blood glucose level in the first hours after transplantation also increases the risk of developing diabetes (95% confidence interval, 1.011-1.021; p = <.001). CONCLUSIONS: Post-kidney transplant patients require immediate follow-up, and attention should be paid to changes in blood glucose level in the first 24 h after transplantation, as any alteration may be an early sign of development of NODAT, especially in patients with a family history of diabetes mellitus.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus/epidemiology , Kidney Transplantation , Adolescent , Child , Diabetes Mellitus/mortality , Female , Graft Survival , Humans , Incidence , Male , Mexico , Retrospective Studies , Risk Factors , Survival Rate
6.
Mol Genet Genomic Med ; 7(11): e981, 2019 11.
Article in English | MEDLINE | ID: mdl-31566927

ABSTRACT

BACKGROUND: Fabry disease (FD) has an extensive phenotypic expression associated with GLA gene variants. The GLA gene variant c.352C>T/p.Arg118Cys was considered with uncertain pathogenicity because of the finding of high residual alpha-galactosidase A (α-Gal A) enzyme activity, the absence of Mendelian segregation with an FD phenotype with many individuals remaining asymptomatic at old ages and the lack of globotriaosylceramide (Gb3) deposits in tissues. Gb3 deposits are found in kidneys before the progression to overt microalbuminuria and decreased glomerular filtration. METHODS: We describe a family with c.352C>T/p.Arg118Cys variant and pathognomonic signs of FD renal damage in masculine children. RESULTS: The proband died of end-stage renal failure and we analyzed GLA gene in his offspring and found the variant in all daughters and five of seven grandchildren. In patients who we measure plasma and urinary Gb3, α-Gal A enzyme activity, and plasma globotriaosylsphingosine (Lyso-Gb3), these were normal or almost normal. A kidney biopsy was performed in two boys and one girl with normal renal function and characteristic signs of FD as enlarged and vacuolated epithelial cells, myelin figures, myelin-like figures, lamellated structures in podocytes and endothelial cells, were found in boys. These boys received agalsidase beta 1 mg/kg IV infusion every other week to prevent further renal damage. CONCLUSION: This is the first report that shows a link between FD renal Gb3 deposits and c.352C>T/p.Arg118Cys variant, supporting pathogenicity of a variant considered until now with uncertain pathogenicity.


Subject(s)
Fabry Disease/metabolism , Kidney Failure, Chronic/metabolism , Kidney/metabolism , Trihexosylceramides/metabolism , Adult , Child , Child, Preschool , Fabry Disease/genetics , Fabry Disease/pathology , Family Health , Female , Humans , Kidney/pathology , Kidney Failure, Chronic/genetics , Kidney Failure, Chronic/pathology , Male , Middle Aged
8.
Bol. méd. Hosp. Infant. Méx ; 73(5): 331-334, sep.-oct. 2016.
Article in Spanish | LILACS | ID: biblio-951247

ABSTRACT

Resumen: Introducción: El síndrome de pseudo-Bartter (SPB) se define como una alcalosis metabólica hipoclorémica con hipocaliemia en ausencia de tubulopatía. Los pacientes con fibrosis quística (FQ), al presentar alteraciones hidrolectrolíticas, pueden llegar a presentarlo. Caso clínico: Lactante femenino con antecedente de 2 eventos de deshidratación. Se presenta a los 5 meses de vida con vómito, rechazo al alimento, tos crónica, poliuria, desnutrición, alcalosis metabólica, hipocaliemia, hiponatremia, hipocloremia y falla renal aguda. Se realizó estudio de tos crónica, con lo que se descartó tuberculosis pulmonar, enfermedad por reflujo gastroesofágico y alteración en la mecánica de la deglución. Ante la alcalosis metabólica sin tubulopatía se diagnosticó SPB; por la historia de desnutrición y tos crónica se sospechó de FQ, la cual se corroboró con medición de electrolitos en sudor y mediante análisis molecular de la mutación delta F508. Este es uno de los pocos casos reportados con SPB y esta mutación. Conclusiones: En pacientes con cuadros repetitivos de deshidratación hiponatrémica con alcalosis metabólica hipoclorémica o SPB debe considerarse como diagnóstico diferencial FQ. La FQ pude presentarse como SPB, principalmente en pacientes menores de 2 años.


Abstract: Background: Pseudo Bartter syndrome (PBS) is defined as hypokalaemic hypochloraemic metabolic alkalosis in the absence of renal tubular pathology. Children with cystic fibrosis (CF) are at risk of developing electrolyte abnormalities and even PBS may occur. Case report: 5 months old female infant with a history of two events of dehydration with vomit, refusal to eat, chronic cough, polyuria, malnutrition, metabolic alkalosis, hypokalemia, hyponatremia, hypochloremia and acute renal failure. Chronic cough study was performed, discarding pulmonary tuberculosis, gastroesophageal reflux disease and impaired swallowing. PBS was diagnosed due to hypokalaemic hypochloraemic metabolic alkalosis in the absence of renal tubular pathology. CF was corroborated by electrolytes in sweat and through molecular analysis of the delta F508 mutation. This is one of the few reported cases linking PBS and this mutation. Conclusions: In patients with hyponatremic dehydration episodes with hypokalaemic hypochloraemic metabolic alkalosis, PBS should be considered as differential diagnosis. CF could be presented as PBS, mainly in patients younger than 2 years.

9.
Bol Med Hosp Infant Mex ; 73(5): 331-334, 2016.
Article in Spanish | MEDLINE | ID: mdl-29384126

ABSTRACT

BACKGROUND: Pseudo Bartter syndrome (PBS) is defined as hypokalaemic hypochloraemic metabolic alkalosis in the absence of renal tubular pathology. Children with cystic fibrosis (CF) are at risk of developing electrolyte abnormalities and even PBS may occur. CASE REPORT: 5 months old female infant with a history of two events of dehydration with vomit, refusal to eat, chronic cough, polyuria, malnutrition, metabolic alkalosis, hypokalemia, hyponatremia, hypochloremia and acute renal failure. Chronic cough study was performed, discarding pulmonary tuberculosis, gastroesophageal reflux disease and impaired swallowing. PBS was diagnosed due to hypokalaemic hypochloraemic metabolic alkalosis in the absence of renal tubular pathology. CF was corroborated by electrolytes in sweat and through molecular analysis of the delta F508 mutation. This is one of the few reported cases linking PBS and this mutation. CONCLUSIONS: In patients with hyponatremic dehydration episodes with hypokalaemic hypochloraemic metabolic alkalosis, PBS should be considered as differential diagnosis. CF could be presented as PBS, mainly in patients younger than 2 years.

10.
Bol. méd. Hosp. Infant. Méx ; 72(3): 190-194, may.-jun. 2015. ilus
Article in Spanish | LILACS | ID: lil-774482

ABSTRACT

ResumenINTRODUCCIÓN: El raquitismo dependiente de vitamina D tipo I es una enfermedad hereditaria rara debida a una mutación en el gen CYP27B1 que codifica la enzima 1 α -hidroxilasa. Se caracteriza por la presentación de raquitismo hipocalcémico grave desde la edad de la lactancia debido al déficit de producción del metabolito activo de la vitamina D, la 1α,25-dihidroxivitamina D3.CASO CLÍNICO: Presentamos el caso de un paciente con raquitismo diagnosticado a los 11 meses de edad y el seguimiento hasta los 9 años.CONCLUSIONES: Se discute la fisiopatología de la enfermedad y la importancia del diagnóstico y tratamiento oportunos.


AbstractBACKGROUND: Vitamin D dependent rickets type I is a rare hereditary disease due to a mutation in CYP27B1 encoding the 1α-hydroxylase gene. Clinically, the condition is characterized by hypocalcemic rickets in early infancy due to a deficit in the production of the vitamin D active metabolite 1,25-dihydroxy-vitamin D3.CASE REPORT: We report the case of a patient diagnosed at 11 months with follow-up until 9 years of age.CONCLUSIONS: The pathophysiology of the disease and the relevance of early diagnosis and management are discussed.

11.
Bol Med Hosp Infant Mex ; 72(3): 190-194, 2015.
Article in Spanish | MEDLINE | ID: mdl-29421501

ABSTRACT

BACKGROUND: Vitamin D dependent rickets type I is a rare hereditary disease due to a mutation in CYP27B1 encoding the 1α-hydroxylase gene. Clinically, the condition is characterized by hypocalcemic rickets in early infancy due to a deficit in the production of the vitamin D active metabolite 1,25-dihydroxy-vitamin D3. CASE REPORT: We report the case of a patient diagnosed at 11 months with follow-up until 9 years of age. CONCLUSIONS: The pathophysiology of the disease and the relevance of early diagnosis and management are discussed.

12.
J Orthop Trauma ; 29(3): e85-90, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24983431

ABSTRACT

OBJECTIVES: The aim of this study was to compare the complications of the trochanteric gamma nail (TGN) and the Gamma3 Nail (G3), focusing on cutout failure. DESIGN: Retrospective comparative cohort analysis. SETTING: Level II Teaching Trauma Center academic trauma center. PATIENTS/METHODS: Two hundred eighteen trochanteric fractures with a mean follow-up of 15 months were included in the study. They were treated either with the TGN or the G3 between January 2005 and December 2010. Bivariate, stratified, and logistic regression analysis was conducted to determine the association between cutout and the independent variables. INTERVENTION: Proximal anterograde nailing with either the TGN or the G3. MAIN OUTCOME MEASUREMENTS: Patient age, sex, type of intramedullary device, stability fracture pattern, tip-apex distance (TAD), distraction at the fracture site, cervical angle, and cutout. RESULTS: The relative risk (RR) of cutout was 4.71 times higher in the group treated with G3 (P < 0.01). RR of cutout for unstable fractures compared with stable fractures was 3.07 (1.01-9.35). In unstable fractures, the RR of cutout was 8.78 times higher in patients with G3 (P < 0.01). RR of cutout was 1.54 times higher with TAD >25 mm (P = 0.4). DISCUSSION: We have not found any relationship between cutout rate and TAD. Only the fracture pattern and the type of implant have shown to be associated with cutout risk. In our study, Gamma3 Nail has higher cutout rates than TGN in unstable fractures. LEVEL OF EVIDENCE: Therapeutic level III. See Instructions for Authors for a complete description of levels of evidence.


Subject(s)
Bone Nails/adverse effects , Fracture Fixation, Intramedullary/adverse effects , Hip Fractures/surgery , Aged , Aged, 80 and over , Female , Fracture Fixation, Intramedullary/instrumentation , Humans , Male , Prosthesis Failure , Retrospective Studies , Risk
13.
Bol. méd. Hosp. Infant. Méx ; 71(5): 298-302, Sep.-Dec. 2014. ilus
Article in Spanish | LILACS | ID: lil-744081

ABSTRACT

Introducción: El síndrome de cascanueces causado por la compresión de la vena renal izquierda entre la aorta y la arteria mesentérica superior es una causa no glomerular de sangrado renal y varicocele izquierdos. También ha sido reconocido como una causa importante de proteinuria ortostática. Caso clínico: Adolescente masculino de 17 años de edad con un cuadro de hematuria recurrente. En el examen físico se observó varicocele izquierdo. Índice de masa corporal de 16.3 kg/m². El examen de orina mostró hematuria y proteinuria masiva. La biopsia renal evidenció proliferación mesangial glomerular leve. El estudio de cistoscopia mostró el origen de la hematuria en el uréter izquierdo. La ultrasonografía Doppler y la angiotomografía de contraste revelaron velocidad pico de la vena renal izquierda de 20 cm/s, relación del índice de flujos de la vena renal izquierda de su porción aortomesentérica e hiliar de 7.7 y agrandamiento de la vena renal izquierda en la porción hiliar. Con el diagnóstico de síndrome de cascanueces se decidió proporcionar tratamiento conservador. En los meses siguientes mostró disminución importante de los episodios de hematuria recurrente, y se observó remisión de las manifestaciones clínicas y de las alteraciones en el examen de orina. A los 13 meses de evolución el índice de masa corporal fue de 19 kg/m². Conclusiones: Este caso clínico muestra la relación entre el incremento en la masa corporal y la remisión del síndrome de cascanueces manifestado como presencia de varicocele izquierdo, hematuria y proteinuria graves. Los síntomas desaparecieron al incrementar el índice de masa corporal, probablemente debido a un aumento en la grasa retroperitoneal que mejoró el ángulo aortomesentérico de la vena renal izquierda.


Background: Nutcracker syndrome caused by compression of the left renal vein between the aorta and superior mesenteric artery is a non-glomerular cause of left renal bleeding and left varicocele. It has also been recognized to be an important cause of orthostatic proteinuria. Case report: A 17-year-old male was evaluated due to recurrent macroscopic hematuria. Physical examination showed left varicocele. Body mass index 16.3 kg/m². Urinalysis demonstrated hematuria and massive proteinuria. Renal biopsy showed mild mesangial glomerular proliferation. Cystoscopy showed hematuria originating from the left ureter. Doppler ultrasonography and contrast-enhanced computed angiotomography revealed a peak velocity of the left renal vein of 20 cm/s, ratio of peak velocity of aortomesenteric and hilar portions of left renal vein of 7.7 and enlargement of the left renal vein in the hilar portion. With a diagnosis of nutcracker syndrome, the patient received conservative treatment. During follow-up, progressive remission of the recurrent episodes of hematuria and proteinuria was observed. The patient had no clinical symptoms or abnormal urinalysis. At 13 months of follow-up the body mass index was 19 kg/m². Conclusions: This case shows the relationship between the increase in body mass index and remission of nutcracker syndrome, manifested as left varicocele, hematuria and massive proteinuria. All symptoms disappeared with the increase of body mass index, probably due to increase in retroperitoneal fat with improvement of the aortomesenteric angle of the left renal vein.

14.
Bol Med Hosp Infant Mex ; 71(5): 298-302, 2014.
Article in Spanish | MEDLINE | ID: mdl-29421619

ABSTRACT

BACKGROUND: Nutcracker syndrome caused by compression of the left renal vein between the aorta and superior mesenteric artery is a non-glomerular cause of left renal bleeding and left varicocele. It has also been recognized to be an important cause of orthostatic proteinuria. CASE REPORT: A 17-year-old male was evaluated due to recurrent macroscopic hematuria. Physical examination showed left varicocele. Body mass index 16.3 kg/m2. Urinalysis demonstrated hematuria and massive proteinuria. Renal biopsy showed mild mesangial glomerular proliferation. Cystoscopy showed hematuria originating from the left ureter. Doppler ultrasonography and contrast-enhanced computed angiotomography revealed a peak velocity of the left renal vein of 20cm/s, ratio of peak velocity of aortomesenteric and hilar portions of left renal vein of 7.7 and enlargement of the left renal vein in the hilar portion. With a diagnosis of nutcracker syndrome, the patient received conservative treatment. During follow-up, progressive remission of the recurrent episodes of hematuria and proteinuria was observed. The patient had no clinical symptoms or abnormal urinalysis. At 13 months of follow-up the body mass index was 19 kg/m2. CONCLUSIONS: This case shows the relationship between the increase in body mass index and remission of nutcracker syndrome, manifested as left varicocele, hematuria and massive proteinuria. All symptoms disappeared with the increase of body mass index, probably due to increase in retroperitoneal fat with improvement of the aortomesenteric angle of the left renal vein.

15.
Indian J Microbiol ; 53(2): 142-8, 2013 Jun.
Article in English | MEDLINE | ID: mdl-24426100

ABSTRACT

Rapid and more sensitive methods for the detection and quantification of viable Legionella cells have been developed. In this paper, a comparative analysis of environmental water samples using the ScanVIT-Legionella™ method and the traditional "gold standard" method of culturing is realised indicating the usefulness of the ScanVIT method. The ScanVIT-Legionella™ method was performed on environmental water samples from different locations of Huesca region (Spain). Legionella micro-colonies should appear green colour and Legionella pneumophila micro-colonies appear red. Twenty-one environmental water samples analysed by standard culture plus five control samples (Two sterile water samples with Legionella as positive controls and three sterile water samples as negative controls). All of them were used to apply ScanVIT-Legionella™ method. From of 21 environmental samples eleven were positive, six negative with both methods and four samples were negative for culture method and positive for ScanVIT-Legionella™ method. The positive control samples were positive and the negative were negative for both methods. A comparative analysis of the results obtained with two methods showed a strong positive determination coefficient (R(2) = 0.99753). The results demonstrate the usefulness of the ScanVIT-Legionella™ method as a rapid diagnostic tool in order to provide a diagnosis as quick as possible. ScanVIT-Legionella™ method offers a series of advantages such as quickly diagnosis, higher sensitivity and the possibility to identify Legionella spp. and L. pneumophila simultaneously.

16.
Rev. mex. ortop. traumatol ; 13(1): 68-73, ene.-feb. 1999. ilus, graf
Article in Spanish | LILACS | ID: lil-254708

ABSTRACT

En el periodo de julio de 1990 a julio de 1994 se captaron 77 pacientes cuyo diagnóstico era dolores de crecimiento -definidos de acuerdo al criterio de Naish y Apley-, en la consulta externa del Hospital Infantil de México; se excluyeron a aquellos pacientes con una patología musculoesquelética evidente, o que tuvieran una alteración en sus resultados de laboratorio o de radiología. Fueron 48 hombres y 35 mujeres, la edad osciló entre tres a 19 años. Se estableció un programa de ejercicio de relajación, por medio de estiramiento muscular (técnica de Baxter); obteniéndose una disminución de la frecuencia e intensidad del dolor a partir de algunas semanas de iniciado el tratamiento. Las diferentes teorías que se han propuesto de como los ejercicios mencionados resuelven el problema, nos obliga a pensar en un origen multifactorial del padecimiento


Subject(s)
Humans , Male , Female , Child, Preschool , Adolescent , Pain/diagnosis , Pain/therapy , Bone and Bones/physiology , Exercise Therapy , Exercise Therapy/education , Growth/physiology , Relaxation Therapy/education , Relaxation Therapy/trends
17.
Rev. mex. ortop. traumatol ; 11(5): 317-26, sept.-oct. 1997. tab, ilus
Article in Spanish | LILACS | ID: lil-227167

ABSTRACT

El menisco es una estructura articular extremadamente importante y en los niños es grueso y rara vez presenta lesiones o deformidad, el menisco discoide es considerado una malformación congénita que puede acompañarse de síntomas severos. El objetivo de nuestro estudio es reportar los resultados de la meniscectomía en niños con este padecimiento, describir la pieza anatómica, los cambios radiológicos y la sintomatología del pacientes, antes y después de la cirugía. Se revisaron 20 pacientes con lesión de meniscos, dolor localizado en la línea interarticular externa durante la flexoextensión, las radiografías mostraron asimetría del espacio articular, 14 fueron operados siendo la causa principal de la cirugía la presencia de menisco discoide; encontramos que la edad promedio en que se presentó fue a los 9 años, la sintomatología más común fue el dolor y el chasqueo de la rodilla. Las secuelas postquirúrgicas que se presentaron fueron molestias sobre todo con los cambios de temperatura y limitación a la flexoextensión que mejoran con el ejercicio


Subject(s)
Pain , Congenital Abnormalities/surgery , Menisci, Tibial/surgery , Menisci, Tibial/injuries , Knee Injuries
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