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PURPOSE: Cost containment and efficiency in the provision of health care are primary concerns for health systems that aim to provide affordable, high-quality care. Between 2005 and 2015, Seguro Poplar's Fund against Catastrophic Expenditures (FPGC) funded ALL treatment in Mexico. Before January 1, 2011, FPGC reimbursed a fixed amount per patient according to risk. In 2011, the per capita reimbursement method changed to fee for service. We used this natural experiment to estimate the impact of the reimbursement policy change on average expenditure and quality of care for ALL treatment in Mexico. METHODS: We used nationwide reimbursement data from the Seguro Poplar's FPGC from 2005 to 2015. We created a patient cohort to assess 3-year survival and estimate the average reimbursement before and after the fee-for-service policy. We examined survival and expenditure impacts, controlling for patients' and providers' characteristics, including sex, risk (standard and high), the volume of patients served, type of institution (federally funded v other), and level of care. To quantify the impact, we used a regression discontinuity approach. RESULTS: The average reimbursement for standard-risk patients in the 3-year survival cohort was $16,512 US dollars (USD; 95% CI, 16,042 to 17,032) before 2011 and $10,205 USD (95% CI, 4,659 to 12,541) under the fee-for-service reimbursement scheme after 2011. The average annual reimbursement per patient decreased by 136% among high-risk patients. The reduction was also significant for the standard-risk cohort, although the magnitude was substantially smaller (34%). CONCLUSION: As Mexico's government is currently restructuring the health system, our study provides evidence of the efficiency and effectiveness of the funding mechanism in the Mexican context. It also serves as a proof of concept for using administrative data to evaluate economic performance and quality of care of publicly funded health programs.
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Planes de Aranceles por Servicios , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , México/epidemiología , Planes de Aranceles por Servicios/economía , Masculino , Femenino , Leucemia-Linfoma Linfoblástico de Células Precursoras/economía , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Adolescente , Adulto , Niño , Gastos en Salud/estadística & datos numéricos , Preescolar , Adulto JovenRESUMEN
Introduction: Data on medulloblastoma outcomes and experiences in low- and middle-income countries, especially in Latin America, is limited. This study examines challenges in Mexico's healthcare system, focusing on assessing outcomes for children with medulloblastoma in a tertiary care setting. Methods: A retrospective analysis was conducted, involving 284 patients treated at 21 pediatric oncology centers in Mexico. Results: High-risk patients exhibited markedly lower event-free survival than standard-risk patients (43.5% vs. 78.3%, p<0.001). Influential factors on survival included anaplastic subtype (HR 2.4, p=0.003), metastatic disease (HR 1.9, p=0.001); residual tumor >1.5cm², and lower radiotherapy doses significantly impacted event-free survival (EFS) and overall survival (OS). Platinum-based chemotherapy showed better results compared to the ICE protocol in terms of OS and EFS, which was associated with higher toxicity. Patients under 3 years old displayed notably lower OS and EFS compared to older children (36.1% vs. 55.9%, p=0.01).
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Background: A heterogeneous geographic distribution of childhood acute lymphoblastic leukemia (ALL) cases has been described, possibly, related to the presence of different environmental factors. The aim of the present study was to explore the geographical distribution of childhood ALL cases in Greater Mexico City (GMC). Methods: A population-based case-control study was conducted. Children <18 years old, newly diagnosed with ALL and residents of GMC were included. Controls were patients without leukemia recruited from second-level public hospitals, frequency-matched by sex, age, and health institution with the cases. The residence address where the patients lived during the last year before diagnosis (cases) or the interview (controls) was used for geolocation. Kulldorff's spatial scan statistic was used to detect spatial clusters (SCs). Relative risks (RR), associated p-value and number of cases included for each cluster were obtained. Results: A total of 1054 cases with ALL were analyzed. Of these, 408 (38.7%) were distributed across eight SCs detected. A relative risk of 1.61 (p<0.0001) was observed for the main cluster. Similar results were noted for the remaining seven ones. Additionally, a proximity between SCs, electrical installations and petrochemical facilities was observed. Conclusions: The identification of SCs in certain regions of GMC suggest the possible role of environmental factors in the etiology of childhood ALL.
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B-cell acute lymphoblastic leukemia (B-ALL) is the most common childhood hematological malignancy worldwide. Treatment outcomes have improved dramatically in recent years; despite this, relapse is still a problem, and the potential molecular explanation for this remains an important field of study. We performed microarray and single-cell RNA-Seq data mining, and we selected significant data with a P -value<0.05. We validated BRCA1 gene expression by means of quantitative (reverse transcription-polymerase chain reaction.) We performed statistical analysis and considered a P -value<0.05 significant. We identified the overexpression of breast cancer 1, early onset (BRCA1; P -value=2.52 -134 ), by means of microarray analysis. Moreover, the normal distribution of BRCA1 expression in healthy bone marrow. In addition, we confirmed the increases in BRCA1 expression using real-time (reverse transcription-polymerase chain reaction and determined that it was significantly reduced in patients with relapse ( P -values=0.026). Finally, we identified that the expression of the BRCA1 gene could predict early relapse ( P -values=0.01). We determined that low expression of BRCA1 was associated with B-cell acute lymphoblastic leukemia relapse and could be a potential molecular prognostic marker.
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Leucemia-Linfoma Linfoblástico de Células Precursoras B , Humanos , Niño , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Pronóstico , Biomarcadores , Resultado del Tratamiento , Recurrencia , Proteína BRCA1RESUMEN
Leukemias are the most common type of pediatric cancer around the world. Prognosis has improved during the last decades, and many patients are cured with conventional treatment as chemotherapy; however, many patients still present with a refractory disease requiring additional treatments, including hematopoietic stem cell transplantation. Immunotherapy with monoclonal antibodies or cellular therapy is a promising strategy for treating refractory or relapsed hematological malignancies. Particularly, CAR-T cells have shown clinical efficacy in clinical trials, and different products are now commercially approved by regulatory agencies in the USA and Europe. Many challenges still need to be solved to improve and optimize the potential of these therapies worldwide. Global access to cell therapy is a significant concern, and different strategies are being explored in the middle- and low-income countries. In Mexico, leukemias represent around 50% of total cancer diagnosed in pediatric patients, and the rate of relapsed or refractory disease is higher than reported in other countries, a multi-factorial problem. Although significant progress has been made during the last decades in leukemia diagnosis and treatment, making new therapies available to Mexican patients is a priority, and cell and gene therapies are on the horizon. Efforts are ongoing to make CAR-T cell therapy accessible for patients in Mexico. This article summarizes a general landscape of childhood leukemias in Mexico, and we give a perspective about the current strategies, advances, and challenges ahead to make gene and cell therapies for leukemia clinically available.
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Acute lymphoblastic leukemia (ALL) is the most common malignancy among Mexican and Hispanic children and the first cause of death by disease in Mexico. We propose a "triple-hit" explanation for the survival gap affecting this population. The first hit can be attributed to epidemiology and social, cultural, and economic burdens. The second hit refers to cancer biology, with a high incidence of unfavorable genetic characteristics associated with an unfavorable response to treatment and, subsequently, poor survival. Finally, the third hit relates to sub-optimal treatment and support. Society and culture, leukemia biology, and treatment approach limitations are key factors that should not be seen apart and must be considered comprehensively in any strategy to improve the prognosis of Mexican and Hispanic children with ALL.
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Introduction: Over the years, the Hispanic population living in the United States has consistently shown high incidence rates of childhood acute leukemias (AL). Similarly, high AL incidence was previously observed in Mexico City (MC). Here, we estimated the AL incidence rates among children under 15 years of age in MC during the period 2010-2017. Methods: The Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia conducted a study gathering clinical and epidemiological information regarding children newly diagnosed with AL at public health institutions of MC. Crude age incidence rates (cAIR) were obtained. Age-standardized incidence rates worldwide (ASIRw) and by municipalities (ASIRm) were calculated by the direct and indirect methods, respectively. These were reported per million population <15 years of age; stratified by age group, sex, AL subtypes, immunophenotype and gene rearrangements. Results: A total of 903 AL cases were registered. The ASIRw was 63.3 (cases per million) for AL, 53.1 for acute lymphoblastic leukemia (ALL), and 9.4 for acute myeloblastic leukemia. The highest cAIR for AL was observed in the age group between 1 and 4 years (male: 102.34 and female: 82.73). By immunophenotype, the ASIRw was 47.3 for B-cell and 3.7 for T-cell. The incidence did not show any significant trends during the study period. The ASIRm for ALL were 68.6, 66.6 and 62.8 at Iztacalco, Venustiano Carranza and Benito Juárez, respectively, whereas, other municipalities exhibited null values mainly for AML. Conclusion: The ASIRw for childhood AL in MC is among the highest reported worldwide. We observed spatial heterogeneity of rates by municipalities. The elevated AL incidence observed in Mexican children may be explained by a combination of genetic background and exposure to environmental risk factors.
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Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Niño , Preescolar , Ciudades , Femenino , Humanos , Incidencia , Lactante , Leucemia Mieloide Aguda/epidemiología , Leucemia Mieloide Aguda/etiología , Masculino , México/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/genéticaRESUMEN
Leukemia is the most common childhood malignancy in Mexico, representing more than 50% of all childhood cancers. Although treatment leads to a survival of up to 90% in developing countries, in our country, it is less than 65%. Additionally, ~30% of patients relapse with poor prognosis. Alternative splicing plays an important role in transcriptome diversity and cellular biology. This mechanism promotes an increase in the assortment of proteins with potentially distinct functions from a single gene. The proliferating cell nuclear antigen (PCNA) gene encodes two transcripts for the same protein of 261 amino acids, which is associated with several important cellular processes and with several types of cancer. However, the diversity of the transcript variants expressed in this condition is not clear. Then, we used microarray gene expression to identify changes in the exon expression level of PCNA. The data were validated using RT-PCR and Sanger sequencing, and three additional transcripts (PCNA_V3, PCNA_V4, and PCNA_V5) were identified. Computational analyses were used to determine the potential proteins resulting, their structure, and interactions with PCNA native protein and themselves. Additionally, the PCNA transcript variants were inhibited using specific siRNA, determining that their inhibition contributes to the malignant characteristics in vitro. Finally, we quantified the PCNA transcript variants in acute lymphoblastic leukemia samples and identified their expression in this disease. Based on the clinical characteristics, we determined that PCNA_V2 and PCNA_V4 are expressed at significantly low levels in relapsed B-ALL patients. We conclude that the low expression of PCNA_V2 and PCNA_V4 could be a potential molecular marker of relapse in acute lymphoblastic leukemia patients.
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Linfoma de Burkitt , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Niño , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Nucleares/metabolismo , ARN Interferente Pequeño , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Recurrencia , Biomarcadores , Enfermedad Aguda , AminoácidosRESUMEN
Ph-like subtypes with CRLF2 abnormalities are frequent among Hispano-Latino children with pre-B ALL. Therefore, there is solid ground to suggest that this subtype is frequent in Mexican patients. The genomic complexity of Ph-like subtype constitutes a challenge for diagnosis, as it requires diverse genomic methodologies that are not widely available in diagnostic centers in Mexico. Here, we propose a diagnostic strategy for Ph-like ALL in accordance with our local capacity. Pre-B ALL patients without recurrent gene fusions (104) were classified using a gene-expression profile based on Ph-like signature genes analyzed by qRT-PCR. The expressions of the CRLF2 transcript and protein were determined by qRT-PCR and flow cytometry. The P2RY8::CRLF2, IGH::CRLF2, ABL1/2 rearrangements, and Ik6 isoform were screened using RT-PCR and FISH. Surrogate markers of Jak2-Stat5/Abl/Ras pathways were analyzed by phosphoflow. Mutations in relevant kinases/transcription factors genes in Ph-like were assessed by target-specific NGS. A total of 40 patients (38.5%) were classified as Ph-like; of these, 36 had abnormalities associated with Jak2-Stat5 and 4 had Abl. The rearrangements IGH::CRLF2,P2RY8::CRLF2, and iAMP21 were particularly frequent. We propose a strategy for the detection of Ph-like patients, by analyzing the overexpression/genetic lesions of CRLF2, the Abl phosphorylation of surrogate markers confirmed by gene rearrangements, and Sanger sequencing.
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Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Reordenamiento Génico , Humanos , México , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Receptores de Citocinas/genética , Receptores de Citocinas/metabolismo , Factor de Transcripción STAT5/metabolismoRESUMEN
The P2RY8-CRLF2 and IGH-CRLF2 rearrangements induce the overexpression of cytokine receptor-like factor 2 (CRLF2) and have been associated with relapse and poor prognosis in B-cell acute lymphoblastic leukemia (B-ALL). Additionally, they are frequently documented in high-risk Hispanic populations. To better understand the potential causes of the adverse prognosis of childhood B-ALL in Mexico, we analyzed these rearrangements and the CRLF2 mRNA and protein levels in 133 Mexican children with B-ALL. We collected bone marrow samples at diagnosis and evaluated the CRLF2 gene expression by qRT-PCR and the total CRLF2 protein by flow cytometry. P2RY8-CRLF2 and IGH-CRLF2 were detected by RT-PCR and FISH, respectively. The median time of follow-up to determine the prognostic significance of the CRLF2 abnormalities was three years. In 82% of the participants, the mRNA levels correlated with the cell-surface and intracellular CRLF2 protein levels. The P2RY8-CRLF2 rearrangement was present in 31.5% (42/133) of the patients, while the IGH-CRLF2 rearrangement was detected in 13.5% (9/67) of patients with high expression of CRLF2 (6.8% of the total sample). CRLF2 copy number variations (gain) were also detected in 7.5% (5/67) of patients with high protein levels. The overall survival (OS) presented significantly lower rates in patients with high white blood cell count (≥50x109/L) regardless of CRLF2 expression, but high levels of CRLF2 gene expression appears to contribute to the reduction of OS within this group of patients. In conclusion, in our cohort, a high occurrence of CRLF2 abnormalities was documented, particularly the P2RY8-CRLF2 rearrangement, which might represent a characteristic of the Mexican population. Targeted therapy to treat this group of patients could improve OS.
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Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Variaciones en el Número de Copia de ADN , Humanos , México , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Pronóstico , ARN Mensajero/genética , Receptores de Citocinas/genéticaRESUMEN
Abstract Background: The association between childhood cancer and socioeconomic status has been widely studied. However, none of the results are conclusive. This study aimed to analyze the association between the Human Development Index (HDI) and the acute lymphoblastic leukemia (ALL) incidence in children under the Popular Medical Insurance Care. Methods: We conducted an observational, descriptive, and population-based study covering 55% of the Mexican population (58 million). Results: The most impoverished states were located in the south east region of Mexico, while the north was more homogeneous, with HDIs varying between 0.73 and 0.79. Our findings emphasize that the metropolitan area of Mexico City and the State of Nuevo Leon have the highest levels of HDI. Regions were graded from I to IV according to their HDIs in ascending order. The HDIs varied from 0.667 to 0.830/100,000 children/year, with a national average of 0.746. The leukemia incidence for regions I, II, III, and IV was 6.12, 6.53, 4.96, and 9.95. An analysis of ALL incidence in Mexico showed significant differences for region IV in comparison with the other regions based on the HDI values (p = 0.0001). Conclusions: Further in-depth studies, including the economic aspects of the different geographic regions and their ethnographic characteristics, would give a more comprehensive panorama.
Resumen Introducción: Se ha estudiado la relación entre el nivel socioeconómico y el cáncer en niños. Sin embargo, aún no existen resultados concluyentes. El objetivo de este trabajo fue analizar la asociación entre el Índice de Desarrollo Humano (IDH) y la incidencia de leucemia linfoblástica aguda en niños atendidos por el Seguro Popular. Métodos: Se realizó un estudio observacional y descriptivo. La población estudiada representa el 55% de la población mexicana (58 millones). Resultados: Los Estados más pobres se localizaron en la región sureste de México, mientras que el norte del país fue más homogéneo, con un IDH que varió entre 0.73 y 0.79. Los hallazgos muestran que el área metropolitana de la Ciudad de México y el Estado de Nuevo León tienen un IDH más alto. Las regiones se graduaron del I al IV en orden ascendente de acuerdo con su IDH. El IDH varió de 0.667 a 0.830 por 100,000 niños por año, con un promedio nacional de 0.746. La incidencia de leucemia por 100,000 niños por año en las regiones I, II, III y IV fue de 6.12, 6.53, 4.96 y 9.95, respectivamente. El análisis de variabilidad de la incidencia de leucemia linfoblástica aguda en México muestra diferencias entre la región IV y el resto de las regiones de acuerdo con los valores del IDH (p = 0.0001). Conclusiones: Se deben realizar estudios más profundos que consideren no solo los aspectos económicos de las diferentes regiones, sino también sus características etnográficas, lo cual podría dar un panorama más amplio.
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The aim of the study was to measure survival of children with acute lymphoblastic leukemia (ALL) under Mexico's public health insurance for the population treated under Seguro Popular. A retrospective cohort study using claims data from Mexico's Seguro Popular program, covering cancer treatment from 2005 to 2015 was conducted. Overall 5-year national and state-specific survival for children with ALL across Mexico who initiated cancer treatment under this program was estimated. From 2005 to 2015, 8,977 children with ALL initiated treatment under Seguro Popular. Under this financing scheme, the annual number of treated children doubled from 535 in 2005 to 1,070 in 2015. The estimates for 5-year overall survival of 61.8% (95%CI 60.8, 62.9) remained constant over time. We observed wide gaps in risk-standardized 5-year overall survival among states ranging from 74.7% to 43.7%. We found a higher risk of mortality for children who received treatment in a non-pediatric specialty hospital (Hazards Ratio, HR = 1.18; 95%CI 1.09, 1.26), facilities without a pediatric oncology/hematology specialist (HR = 2.17; 95%CI 1.62, 2.90), and hospitals with low patient volume (HR = 1.22; 95%CI 1.13, 1.32). In a decade Mexico's Seguro Popular doubled access to ALL treatment for covered children and by 2015 financed the vast majority of estimated ALL cases for that population. While some progress in ALL survival may have been achieved, nationwide 5-year overall survival did not improve over time and did not achieve levels found in comparable countries. Our results provide lessons for Mexico's evolving health system and for countries moving toward universal health coverage.
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Leucemia-Linfoma Linfoblástico de Células Precursoras , Cobertura Universal del Seguro de Salud , Niño , Humanos , Seguro de Salud , México/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Estudios RetrospectivosRESUMEN
PURPOSE OF REVIEW: Acute leukemias represent a tremendous threat to public health around the globe and the main cause of death due to disease in scholar age children from developing nations. Here, we review their current status in Mexico, as a paradigm of study, and the major challenges to control systemic diseases like childhood cancer. RECENT FINDINGS: A unique molecular epidemiology, late/low precision diagnosis, limited access to treatment, toxicity associated with therapy, continuous exposure to environmental risk factors, and the high frequency of early relapses are some of the factors cooperating to low rates of survival in low-to-medium-income countries. Deliberative dialogues and exhaustive programs have emerged as promising means of advancing evidence-informed policy, by providing a structured forum for key stakeholders to integrate scientific and pragmatic knowledge about complex health concerns. A system-wide strategy based on the comprehensive leukemia identity is essential for a meaningful decline in early childhood mortality.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Países en Desarrollo , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Niño , Terapia Combinada , Humanos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: The association between childhood cancer and socioeconomic status has been widely studied. However, none of the results are conclusive. This study aimed to analyze the association between the Human Development Index (HDI) and the acute lymphoblastic leukemia (ALL) incidence in children under the Popular Medical Insurance Care. METHODS: We conducted an observational, descriptive, and population-based study covering 55% of the Mexican population (58 million). RESULTS: The most impoverished states were located in the south east region of Mexico, while the north was more homogeneous, with HDIs varying between 0.73 and 0.79. Our findings emphasize that the metropolitan area of Mexico City and the State of Nuevo Leon have the highest levels of HDI. Regions were graded from I to IV according to their HDIs in ascending order. The HDIs varied from 0.667 to 0.830/100,000 children/year, with a national average of 0.746. The leukemia incidence for regions I, II, III, and IV was 6.12, 6.53, 4.96, and 9.95. An analysis of ALL incidence in Mexico showed significant differences for region IV in comparison with the other regions based on the HDI values (p = 0.0001). CONCLUSIONS: Further in-depth studies, including the economic aspects of the different geographic regions and their ethnographic characteristics, would give a more comprehensive panorama.
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INTRODUCTION AND HYPOTHESIS: Uncomplicated urinary tract infection (uUTI) is defined as the presence of pathogenic organisms in the urinary tract without anatomical and functional abnormalities, is accompanied by inflammatory leukocytes and cytokines and may or may not develop clinical symptoms. The frequency of uncomplicated urinary tract infection is higher in young women. Several quinolone treatment regimens are available; however, since we do not know which is the best antibiotic regimen for the treatment of this urinary infection, we analyzed the published evidence and conducted a systematic review with network meta-analysis. The aim was to compare and hierarchize quinolones according to their efficacy and safety and to identify the best treatment for uncomplicated urinary tract infection in women through a systematic review with network meta-analysis. METHODS: Medline, Embase, LILACS, Cochrane CENTRAL and other databases were searched for trials. Bias in the trials was assessed using the Cochrane Collaboration tool. To analyze efficacy and adverse events, for direct comparisons, we obtained risk ratios and 95% confidence intervals by applying a fixed-effects model using tau2 and Q2 tests to calculate the heterogeneity. For the network meta-analysis, we analyzed the indirect comparisons by Bucher's method. RESULTS: We included 18 trials (8765 women). For premenopausal women, ofloxacin had a 57% probability of achieving remission but an 83% frequency of adverse events. For postmenopausal women, ofloxacin was 82% more effective for remission, with a 49% frequency of adverse events, compared with other types of quinolones. CONCLUSIONS: Compared with other quinolones, ofloxacin 200 mg once daily for a treatment duration < 3 days provides the highest clinical and bacteriological remission rates with the lowest relapse and resistance rates for the treatment of women with uUTIs. However, additional trials are needed to confirm our findings, especially when the treatment duration exceeds 3 days.
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Quinolonas , Infecciones Urinarias , Antibacterianos/efectos adversos , Enfermedad Crónica , Femenino , Humanos , Metaanálisis en Red , Quinolonas/efectos adversos , Infecciones Urinarias/tratamiento farmacológicoRESUMEN
BACKGROUND: B-cell acute lymphoblastic leukemia (B-ALL) is the most commonly diagnosed childhood malignancy worldwide and is especially common in Mexico. Additionally, the number of cases has increased in recent years. Thus, it is very important to develop molecular strategies to diagnose leukemia. The aim of this study was to investigate MYB expression and to determine its impact on the diagnosis of B-ALL. METHODS: We analyzed the B-ALL gene expression profile by microarray data mining. Bioinformatics analysis was performed to identify the genes that are overexpressed in leukemia. We determined that MYB was highly expressed in leukemia. Then, we validated MYB expression in 70 patients with B-ALL and in 16 healthy controls (HCs) using qRT-PCR. The results were statistically analyzed using the Kolmogorov-Smirnov Z test, Mann-Whitney U test, receiver operating characteristic curves, and the Youden index. RESULTS: The microarrays showed that MYB was overexpressed in B-ALL patients with a fold change of 57.8728 and a P value of 2.56-195 . MYB expression showed great variability among the patients analyzed. However, compared to the HCs, the B-ALL patients had a P value < .0001, an area under the curve of 0.813, and a Youden index of 1.46, indicating the statistical significance. CONCLUSION: MYB expression in B-ALL cells could be a potential molecular marker for childhood leukemia.
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Linfocitos B , Genes myb , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Niño , Preescolar , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Lactante , Masculino , Patología MolecularRESUMEN
It is important to study the relationship between extremely low-frequency magnetic fields (ELF-MFs) and childhood leukemia, particularly in locations with a high incidence of this neoplasm in children and an elevated exposure to ELF-MF, such as Mexico City. The aim was to investigate the association between ELF-MF exposure and the risk of B-lineage acute lymphoblastic leukemia (B-ALL). A case-control study was conducted in Mexico City during the period from 2010 to 2011. Residential 24-h ELF-MF measurements were obtained for 290 incident B-ALL patients and 407 controls, aged less than 16 years. Controls were frequency-matched by sex, age (±18 months), and health institution. The adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were calculated. ELF-MF exposure at <0.2 µT was used to define the reference group. ELF-MF exposure at ≥0.3 µT was observed in 11.3% of the controls. Different ELF-MF intensity cutoff values were used to define the highest exposure category; the highest exposure category for each cutoff value was associated with an increased risk of B-ALL compared with the corresponding lower exposure categories. The aORs were as follows: ≥0.2 µT = 1.26 (95% CI: 0.84-1.89); ≥0.3 µT = 1.53 (95% CI: 0.95-2.48); ≥0.4 µT = 1.87 (95% CI: 1.04-3.35); ≥0.5 µT = 1.80 (95% CI 0.95-3.44); ≥0.6 µT = 2.32 (95% CI: 1.10-4.93). ELF-MF exposure as a continuous variable (per 0.2 µT intervals) was associated with B-ALL risk (aOR = 1.06; 95% CI: 1.01-1.12). In the present study, the proportion of children exposed to ≥0.3 µT is among the highest reported worldwide. Additionally, an ELF-MF exposure ≥0.4 µT may be associated with the risk of B-ALL. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.
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Exposición a Riesgos Ambientales/efectos adversos , Campos Magnéticos/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Ciudades/epidemiología , Femenino , Humanos , Incidencia , MasculinoRESUMEN
BACKGROUND: The parental age at conception has been reported to be a risk factor for childhood acute leukaemia (AL); however, the relationship is controversial. The aim of the present study was to investigate the association between parental age at conception and the risk of AL in Mexican children, a population with a high incidence of the disease and a high prevalence of pregnancies in adolescents and young adults. METHODS: A multicentre case-control study was conducted. Incident AL cases younger than 17 years of age diagnosed between 2010 and 2015 were included. Controls were matched with cases according to age, sex, and health institution. Using logistic regression analysis, adjusted odds ratios (aOR) and 95 % confidence intervals (95 % CI) were calculated for each maternal stratum after adjusting for paternal age at conception of index child. The maternal age between 25 and 29.99 years was selected as the reference category. RESULTS: In most strata where maternal and paternal ages were assessed, no association was found with the risk of developing acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML) in their offspring. An increased risk for AML was observed when the mother was between 20 and 24.99 years of age and the father aged 25-29.99 years (aOR, 1.94; 95 % CI, 1.03-3.67). In addition, there was a positive association for ALL when the mother´s age was between 20 and 24.99 years and the father was <20 years of age, however, a very wide confidence interval was noted (aOR, 12.26; 95 % CI, 1.41-106.83). CONCLUSION: In the present study, maternal and paternal ages assessed in different strata showed little association with risk of developing ALL and AML in children. Positive associations between risk of both types of childhood AL were observed with younger paternal and maternal ages.
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Fertilización , Leucemia Mieloide Aguda/epidemiología , Edad Materna , Edad Paterna , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , México/epidemiología , Oportunidad Relativa , Embarazo , Factores de Riesgo , Adulto JovenRESUMEN
B-cell acute lymphoblastic leukemia is the most commonly diagnosed childhood malignancy worldwide; more than 50% of these cases are diagnosed in Mexico. Although the five-year survival rate is >80%, 30% of patients experience relapse with poor prognosis. Cancer-associated gene expression profiles have been identified in several malignancies, and some transcripts have been used to predict disease prognosis. The human transcriptome is incompletely elucidated; moreover, more than 80% of transcripts can be processed via alternative splicing (AS), which increases transcript and protein diversity. The human transcriptome is divided; coding RNA accounts for 2%, and the remaining 98% is noncoding RNA. Noncoding RNA can undergo AS, promoting the diversity of noncoding transcripts. We designed specific primers to amplify previously reported alternative transcript variants of ZNF695 and showed that six ZNF695 transcript variants are co-expressed in cancer cell lines. The amplicons were sequenced and identified. Additionally, we analyzed the expression of these six transcript variants in bone marrow from B-cell acute lymphoblastic leukemia patients and observed that ZNF695 transcript variants one and three were the predominant variants expressed in leukemia. Moreover, our results showed the co-expression of coding and long noncoding RNA. Finally, we observed that long noncoding RNA ZNF695 expression predicted survival rates.
Asunto(s)
Empalme Alternativo , Biomarcadores de Tumor/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Células Cultivadas , Niño , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Células MCF-7 , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
A high impact of ARID5B SNPs on acute lymphoblastic leukemia (ALL) susceptibility has been described in Hispanic children; therefore, it is relevant to know if they influence the high incidence of childhood-ALL in Mexicans. Seven SNPs (rs10821936, rs10994982, rs7089424, rs2393732, rs2393782, rs2893881, rs4948488) of ARID5B were analyzed in 384 controls and 298 ALL children using genomic DNA and TaqMan probes. The SNPs were analyzed for deviation of Hardy-Weinberg equilibrium; Fisher's exact test was used to compare the genotypic and allelic frequencies between controls and patients. The association between SNPs and ALL susceptibility was calculated, and haplotype and ancestry analyses were conducted. All SNPs were associated with ALL, pre-B ALL, and hyperdiploid-ALL susceptibility (p < 0.05). No association with T-ALL and gene fusions was found (p > 0.05). The seven SNPs were associated with risk of pre-B ALL in younger children; however, rs2393732, rs2393782, rs2893881, and rs4948488 were not associated with susceptibility in older children and adolescents. The CAG haplotype (rs10821936, rs10994982, rs7089424) was strongly associated with ALL risk in our population (p < 0.00001). The frequency of all risk alleles in our ALL, pre-B, and hyperdiploid-ALL patients was higher than that in Hispanic children reported. This is the first report showing the association between rs2393732, rs2393782, and rs4948488 with pre-B hyperdiploid-ALL children. The G allele at rs2893881 confers major risk for pre-B hyperdiploid-ALL in Mexican (OR, 2.29) than in Hispanic children (OR, 1.71). The genetic background of our population could influence the susceptibility to ALL and explain its high incidence in Mexico.