Extrahypothalamic oxytocin neurons drive stress-induced social vigilance and avoidance.

Oxytocin increases the salience of both positive and negative social contexts and it is thought that these diverse actions on behavior are mediated in part through circuit-specific action. This hypothesis is based primarily on manipulations of oxytocin receptor function, leaving open the question of whether different populations of oxytocin neurons mediate different effects on behavior. Here we inhibited oxytocin synthesis in a stress-sensitive population of oxytocin neurons specifically within the medioventral bed nucleus of the stria terminalis (BNSTmv). Oxytocin knockdown prevented social stress-induced increases in social vigilance and decreases in social approach. Viral tracing of BNSTmv oxytocin neurons revealed fibers in regions controlling defensive behaviors, including lateral hypothalamus, anterior hypothalamus, and anteromedial BNST (BNSTam). Oxytocin infusion into BNSTam in stress naïve mice increased social vigilance and reduced social approach. These results show that a population of extrahypothalamic oxytocin neurons plays a key role in controlling stress-induced social anxiety behaviors.

Oxytocin receptor behavioral effects and cell types in the bed nucleus of the stria terminalis.

Oxytocin is a neuropeptide that can produce anxiolytic effects and promote social approach. However, emerging evidence shows that under some conditions, oxytocin can instead induce anxiety-related behaviors. These diverse effects of oxytocin appear to be mediated by circuit-specific actions. Recent data showed that inhibition of oxytocin receptors (OTRs) in the bed nucleus of the stria terminalis (BNST) was sufficient to increase social approach and decrease social vigilance in female California mice (Peromyscus californicus) exposed to social defeat stress. As a member of the G-protein coupled receptor family, OTRs can induce distinct downstream pathways by coupling to different G-protein isoforms. We show that infusion of carbetocin, a biased OTR-Gq agonist, in the BNST reduced social approach in both female and male California mice. In both females and males, carbetocin also increased social vigilance. To gain insight into cell types that could be mediating this effect, we analyzed previously published single-cell RNAseq data from the BNST and nucleus accumbens (NAc). In the NAc, we and others showed that OTR activation promotes social approach behaviors. In the BNST, Oxtr was expressed in over 40 cell types, that span both posterior and anterior subregions of the BNST. The majority of Oxtr-expressing neurons were GABAergic. In the anterior regions of BNST targeted in our carbetocin experiments, Cyp26b1-expressing neurons had high average Oxtr expression. In the NAc, most Oxtr+ cells were D1 dopamine receptor-expressing neurons and interneurons. These differences in Oxtr cell type distribution may help explain how activation of OTR in BNST versus NAc can have different effects on social approach and social vigilance.

Adipokines, insulin resistance, and adiposity as a predictors of metabolic syndrome in child survivors of lymphoma and acute lymphoblastic leukemia of a developing country.

BACKGROUND: There is a growing body of evidence indicating that pediatric survivors of cancer are at a greater risk of developing metabolic syndrome. This study evaluated some probable predictors of metabolic syndrome (MS), such as leptin and adiponectin concentrations, the leptin/adiponectin ratio, insulin resistance, and adiposity, in a sample of child survivors of lymphoma and leukemia in Mexico City. METHODS: Fifty two children (leukemia n = 26, lymphoma n = 26), who were within the first 5 years after cessation of therapy, were considered as eligible to participate in the study. Testing included fasting insulin, glucose, adipokines and lipids; body fat mass was measured by DXA. The MS components were analyzed according to tertiles of adipokines, insulin resistance, and adiposity. Comparisons between continuous variables were performed according to the data distribution. The MS components were analyzed according to tertiles of adipokines, insulin resistance, and adiposity. With the purpose of assessing the risk of a present MS diagnosis, odds ratios (OR) with a 95% confidence interval (95% IC) were obtained using logistic regression analysis according to the various metabolic markers. RESULTS: The median children age was 12.1 years, and the interval time from the completion of therapy to study enrollment was 4 years. Among the MS components, the prevalence of HDL-C low was most common (42%), followed by central obesity (29%). The HOMA-IR (OR 9.0, 95% CI 2.0; 41.1), body fat (OR 5.5, 95% CI 1.6; 19.3), leptin level (OR 5.7, 95% CI 1.6; 20.2) and leptin/adiponectin ratio (OR 9.4, 95% CI 2.0; 49.8) in the highest tertile, were predictive factors of developing MS; whereas the lowest tertile of adiponectin was associated with a protective effect but not significant. CONCLUSIONS: Biomarkers such as HOMA-IR, leptin and leptin/adiponectin are associated with each of the components of the MS and with a heightened risk of suffering MS among children survivors of cancer. Given the close relationship between MS with risk of developing type 2 diabetes and cardiovascular disease, it is imperative to implement prevention measures in this population and especially in developing countries where these pathologies have become the leading cause of death.

The effects of the industrial transition on lower limb bone structure: A comparison of the inhabitants of Pecos Pueblo and present-day Indigenous peoples of New Mexico.

OBJECTIVES: Comparisons between Indigenous peoples over time and within a particular geographic region can shed light on the impact of environmental transitions on the skeleton, including relative bone strength, sexual dimorphism, and age-related changes. Here we compare long bone structural properties of the inhabitants of the late prehistoric-early historic Pecos Pueblo with those of present-day Indigenous individuals from New Mexico. MATERIALS AND METHODS: Femora and tibiae of 126 adults from Pecos Pueblo and 226 present-day adults were included in the study. Cross-sectional diaphyseal properties-areas and second moments of area-were obtained from past studies of the Pecos Pueblo skeletal sample, and from computed tomography scans of recently deceased individuals in the present-day sample. RESULTS: Femora and tibiae from Pecos individuals are stronger relative to body size than those of present-day Indigenous individuals. Present-day individuals are taller but not wider, and this body shape difference affects cross-sectional shape, more strongly proximally. The tibia shows anteroposterior strengthening among Pecos individuals, especially among males. Sexual dimorphism in midshaft bone shape is stronger within the Pecos Pueblo sample. With aging, Pecos individuals show more medullary expansion but also more subperiosteal expansion than present-day individuals, maintaining bone strength despite cortical thinning. DISCUSSION: Higher activity levels, carried out over rough terrain and throughout adult life, likely explain the relatively stronger lower limb bones of the Pecos individuals, as well as their greater subperiosteal expansion with aging. Greater sexual dimorphism in bone structure among Pecos individuals potentially reflects greater gender-based differences in behavioral patterns.

Effects of the energy balance transition on bone mass and strength.

Chronic positive energy balance has surged among societies worldwide due to increasing dietary energy intake and decreasing physical activity, a phenomenon called the energy balance transition. Here, we investigate the effects of this transition on bone mass and strength. We focus on the Indigenous peoples of New Mexico in the United States, a rare case of a group for which data can be compared between individuals living before and after the start of the transition. We show that since the transition began, bone strength in the leg has markedly decreased, even though bone mass has apparently increased. Decreased bone strength, coupled with a high prevalence of obesity, has resulted in many people today having weaker bones that must sustain excessively heavy loads, potentially heightening their risk of a bone fracture. These findings may provide insight into more widespread upward trends in bone fragility and fracture risk among societies undergoing the energy balance transition.

Diagnoses unveiled by early bronchoscopy in children with leukemia and pulmonary infiltrates.

Pulmonary complications in children with leukemia often display nonspecific clinical and radiologic manifestations that lead to a delay in diagnosis. The role of fiberoptic bronchoscopy (FOB) and the proper time for its performance are controversial. The aim of our study was to evaluate the frequency and nature of specific diagnoses revealed by FOB. Children with leukemia submitted to FOB because of suspicion of pulmonary involvement (mainly pneumonia) were retrospectively analyzed. A total of 33 FOB procedures performed in 31 patients (20 males) with an average age of 9.4 years (range, 3.5 to 15 y) were evaluated. Microorganisms isolated from 21 (63.6%) bronchoalveolar lavage samples were mainly fungi including Candida in 13 cases (39.4%) and Aspergillus in 3 cases (9.1%). Isolation rate in 10 procedures performed within the first 3 days was 90%. Tracheobronchitis was present in > 50% of patients, pulmonary hemorrhage was seen in 7 (21.0%) patients, and leukemic infiltration was demonstrated in 2 patients (6.1%), among other conditions visualized by FOB. Complications of FOB were minimal and transient. Our study suggests that FOB is a useful and safe procedure in patients with leukemia and pulmonary infiltrates. The earlier the FOB was performed, the higher the isolation rate of causative agents. In addition, this procedure allowed the identification of noninfectious airway comorbidities. Further studies in regard to this issue are warranted.

Bioaccumulation of trace metals in two oyster species from southwest Puerto Rico.

As coastal ecosystems are impacted by land use change and anthropogenic activities, oysters can be an important tool for monitoring local water quality. We collected oysters (Crassostrea rhizophorae and Isognomon alatus) from coastal sites near Guánica and La Parguera in southwest Puerto Rico and analyzed their tissue for concentrations of Ag, As, Cd, Co, Cr, Cu, Ni, Pb, V, and Zn. All trace metals were found in both species, with high bioaccumulation factors for Ag, Cd, and Zn in both species and Cr in C. rhizophorae. Some trace metals are likely associated with anthropogenic sources, including paints and vehicles (Cu and Zn), oil (Ni and V), and wood preservatives (As). Cr in oysters near Guánica is most likely associated with sediment from erosion in the watershed. Both species could be used to monitor changes in trace metal concentrations and the influence of future watershed management strategies in the region.

Childhood acute leukemias are frequent in Mexico City: descriptive epidemiology.

BACKGROUND: Worldwide, acute leukemia is the most common type of childhood cancer. It is particularly common in the Hispanic populations residing in the United States, Costa Rica, and Mexico City. The objective of this study was to determine the incidence of acute leukemia in children who were diagnosed and treated in public hospitals in Mexico City. METHODS: Included in this study were those children, under 15 years of age and residents of Mexico City, who were diagnosed in 2006 and 2007 with leukemia, as determined by using the International Classification of Childhood Cancer. The average annual incidence rates (AAIR), and the standardized average annual incidence rates (SAAIR) per million children were calculated. We calculated crude, age- and sex-specific incidence rates and adjusted for age by the direct method with the world population as standard. We determined if there were a correlation between the incidence of acute leukemias in the various boroughs of Mexico City and either the number of agricultural hectares, the average number of persons per household, or the municipal human development index for Mexico (used as a reference of socio-economic level). RESULTS: Although a total of 610 new cases of leukemia were registered during 2006-2007, only 228 fit the criteria for inclusion in this study. The overall SAAIR was 57.6 per million children (95% CI, 46.9-68.3); acute lymphoblastic leukemia (ALL) was the most frequent type of leukemia, constituting 85.1% of the cases (SAAIR: 49.5 per million), followed by acute myeloblastic leukemia at 12.3% (SAAIR: 6.9 per million), and chronic myeloid leukemia at 1.7% (SAAIR: 0.9 per million). The 1-4 years age group had the highest SAAIR for ALL (77.7 per million). For cases of ALL, 73.2% had precursor B-cell immunophenotype (SAAIR: 35.8 per million) and 12.4% had T-cell immunophenotype (SAAIR 6.3 per million). The peak ages for ALL were 2-6 years and 8-10 years. More than half the children (58.8%) were classified as high risk. There was a positive correlation between the average number of persons per household and the incidence of the pre-B immunophenotype (Pearson's r, 0.789; P = 0.02). CONCLUSIONS: The frequency of ALL in Mexico City is among the highest in the world, similar to those found for Hispanics in the United States and in Costa Rica.

Father's occupational exposure to carcinogenic agents and childhood acute leukemia: a new method to assess exposure (a case-control study).

BACKGROUND: Medical research has not been able to establish whether a father's occupational exposures are associated with the development of acute leukemia (AL) in their offspring. The studies conducted have weaknesses that have generated a misclassification of such exposure. Occupations and exposures to substances associated with childhood cancer are not very frequently encountered in the general population; thus, the reported risks are both inconsistent and inaccurate. In this study, to assess exposure we used a new method, an exposure index, which took into consideration the industrial branch, specific position, use of protective equipment, substances at work, degree of contact with such substances, and time of exposure. This index allowed us to obtain a grade, which permitted the identification of individuals according to their level of exposure to known or potentially carcinogenic agents that are not necessarily specifically identified as risk factors for leukemia. The aim of this study was to determine the association between a father's occupational exposure to carcinogenic agents and the presence of AL in their offspring. METHODS: From 1999 to 2000, a case-control study was performed with 193 children who reside in Mexico City and had been diagnosed with AL. The initial sample-size calculation was 150 children per group, assessed with an expected odds ratio (OR) of three and a minimum exposure frequency of 15.8%. These children were matched by age, sex, and institution with 193 pediatric surgical patients at secondary-care hospitals. A questionnaire was used to determine each child's background and the characteristics of the father's occupation(s). In order to determine the level of exposure to carcinogenic agents, a previously validated exposure index (occupational exposure index, OEI) was used. The consistency and validity of the index were assessed by a questionnaire comparison, the sensory recognition of the work area, and an expert's opinion. RESULTS: The adjusted ORs and 95% confidence intervals (CI) were 1.69 (0.98, 2.92) during the preconception period; 1.98 (1.13, 3.45) during the index pregnancy; 2.11 (1.17, 3.78) during breastfeeding period; 2.17 (1.28, 3.66) after birth; and 2.06 (1.24, 3.42) for global exposure. CONCLUSION: This is the first study in which an OEI was used to assess a father's occupational exposure to carcinogenic agents as a risk factor for the development of childhood AL in his offspring. From our results, we conclude that children whose fathers have been exposed to a high level of carcinogenic agents seem to have a greater risk of developing acute leukemia. However, confounding factors cannot be disregarded due to an incomplete control for confounding.

Incidence of leukemias in children from El Salvador and Mexico City between 1996 and 2000: population-based data.

BACKGROUND: There are very few studies that report the incidence of acute leukemias in children in Latin America. This work assesses the incidence of acute leukemias, between 1996 and 2000, in children from 0-14 years old who were attended at the Mexican Social Security Institute in Mexico City and in children from 0-11 years old in El Salvador. DESIGN: Population-based data. Hospitals: In San Salvador, El Salvador, Hospital Nacional de Niños "Benjamin Bloom", the only center in El Salvador which attends all children, younger than 12 years, with oncologic disease. The Pediatric Hospital and the General Hospital of the Mexican Social Security Institute in Mexico City, the only centers in Mexico City which attend all those children with acute leukemia who have a right to this service. DIAGNOSIS: All patients were diagnosed by bone marrow smear and were divided into acute lymphoid leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), and unspecified leukemias (UL). The annual incidence rate (AIR) and average annual incidence rate (AAIR) were calculated per million children. Cases were stratified by age and assigned to one of four age strata: 1) <1 year; 2) 1-4 years; 3) 5-9 years, or 4) 10-14 or 10-11 years, for Mexico City and El Salvador, respectively. RESULTS: The number of cases was 375 and 238 in El Salvador and Mexico City, respectively. AAIRs in Mexico City were 44.9, 10.6, 2.5, 0.5, and 58.4 per million children for ALL, AML, CML, UL, and total leukemias, respectively. The AAIRs in El Salvador could not be calculated because the fourth age stratum in El Salvador included children only from 0-11 years old. The incidence rates for the Salvadorian group of 0-11 year olds were 34.2, 7.1, 0.6, 0.2, and 43.2 per million children for ALL, AML, CML, UL, and total leukemias, respectively. CONCLUSION: Reported AIRs for each age group in El Salvador were similar to those from other American countries. The AAIR of ALL in Mexico City is one of the highest reported for North America.

Inmunoterapia con alérgenos de ácaros en pacientes con rinitis alérgica y apnea obstructiva del sueño / Immunotherapy with mite allergens in patients with allergic rhinitis and obstructive sleep apnea

Para confirmar la presencia de apneea obstructiva del sueño (OSA) en rinitis alérgica (RA), se realizó poligrafía cardiorrespiratoria (CRP) y para tratar ambas condiciones, inmunoterapia alérgeno específica (ITAE). El diseño fue descriptivo en el universo de pacientes del servicio de Alergología del policlínico Previsora en Camagüey, Cuba, desde diciembre 2018 a marzo 2020. Se seleccionaron 326 pacientes en orden consecutivo de asistencia a la consulta, teniendo en cuenta los criterios: ≥5 años con RA, sospecha de OSA y prueba cutánea con ácaros: Dermatophagoides pteronyssinus, Dermatophagoides siboney y Blomia tropicalis, producidos en: Centro Nacional de Biopreparados de Cuba. Todos recibieron ASIT por ≥10 meses y se realizó CRP antes y después de la ASIT. La CRP se realizó utilizando el marcaje automático de eventos de ApneaLink AirTM (Resmed Corp., RFA), validado para estudiar los trastornos del sueño en el hogar. Los resultados de la prueba cutánea y de CRP se evaluaron antes y después de la ASIT; también la eficacia de la ASIT según criterios de pacientes y profesionales. De la muestra, 152 fueron del sexo femenino y 174 del sexo masculino para un 46,6 por ciento y 53,4 por ciento respectivamente; aquellos con habón de 5 a 6 mm fueron los más representados (p=0,04). Hubo descenso en los niveles de gravedad de OSA después de la ASIT (p=0,025). En la valoración de la eficacia de la ASIT, hubo un número significativo de mejorados (p=0,012). La CRP proporciona el diagnóstico de OSA en RA, y la ASIT cambia el curso de ambas condiciones(AU)

To confirm the presence of obstructive sleep apnea (OSA) in allergic rhinitis (AR), cardiorespiratory polygraphy (CRP) was performed, and to treat both conditions, the allergen specific immunotherapy (ASIT) was used in order to change their course. Descriptive study in the universe of patients from Previsora polyclinic Allergology service, Camagüey, Cuba was carried-out from December 2018 to March 2020. 326 patients were selected in consecutive order of attendance at the consultation, taking into account the criteria: ≥5 years with AR, suspicion of OSA and positive skin test to: Dermatophagoides pteronyssinus, Dermatophagoides siboney and Blomia tropicalis, supplied by the National Center for Biopreparations in Cuba. All patients received ASIT for ≥10 months and CRP was performed before and after ASIT. The CRP results were taken from the automatic scoring of the ApneaLink AirTM device (Resmed Corp., Australia), validated to study OSA at home. The skin test and CRP results were evaluated before and after the ASIT. In addition, the assessment of the ASIT efficacy according to criteria of patients and professionals was performed. The sample was made-up of 152 female patients (46.6 percent) and 174 males (53.4 percent); those with 5 to 6 mm wheal were the most represented (p=0.04). There was decrease in OSA severity levels after ASIT (p=0.025). The ASIT efficacy was proved with a significant number of improvements (p=0.012). CRP provides the diagnosis of OSA in AR, and ASIT changes the course of both conditions(AU)

Importancia de los alérgenos de ácaros domésticos en el diagnóstico de la rinitis alérgica con síndrome de apnea-hipopnea del sueño / Importance of household mite allergens in the diagnosis of allergic rhinitis with sleep apnea-hypopnea syndrome

Los ácaros Dermatophagoides pteronyssinus (Dp), Dermatophagoides siboney (Ds) y Blomia tropicalis (Bt), constituyen la herramienta fundamental para diagnóstico e inmunoterapia de rinitis alérgica (RA), que en muchas ocasiones se asocia al síndrome apnea-hipopnea obstructiva del sueño (SAHOS). Para diagnosticar SAHOS se seleccionaron 465 individuos del registro de alergia del Policlínico Previsora, Camagüey, Cuba, con diagnóstico presuntivo de RA. Se descartaron aquellos con prueba cutánea Prick test negativa a Dp, Ds y Bt y sin poligrafía cardio-respiratoria (PCR), quedando para estudio 236 pacientes entre 8 y 70 años de edad: 102 casos (43,2 por ciento) definidos como aquellos con respiración oral y ronquidos y 134 controles (56,7 por ciento) sin respiración oral ni ronquidos. La PCR se realizó utilizando el marcaje automático de eventos del dispositivo ApneaLink AirTM (Resmed Corp., RFA). La media del tamaño del habón fue de 5,9 mm en los casos (p=0,02). El índice de apnea e hipopnea (IAH) fue positivo en 129 pacientes (54,6 por ciento); de ellos, 97 casos (41,1 por ciento) y 32 controles (13,5 por ciento). Los pacientes con IAH˃20/h predominaron en los casos con 21 individuos (8,8 por ciento) (p꞊0,048). La sensibilidad del PCR fue del 95,10 por ciento, su especificidad del 76,12 por ciento. Los valores predictivos positivos y negativos del 75,19 por ciento y 95,33 por ciento respectivamente. Se estimó en 3,98 la razón de verosimilitud positiva y de 0,06 la negativa. Los pacientes con SAHOS en los casos y controles presentan incremento con predominio para casos (p=0,002). La PCR con el dispositivo ApneaLink permite hacer el diagnóstico de SAHOS en RA(AU)

The mites Dermatophagoides pteronyssinus (Dp), Dermatophagoides siboney (Ds) and Blomia tropicalis (Bt) are the primary tool for the diagnosis and immunotherapy of Allergic Rhinitis (AR), which is often associated with the Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS). To diagnose OSAHS, 465 individuals were selected from the allergy registry of the Previsora Polyclinic, Camagüey, Cuba, with presumptive diagnosis of AR. Those with a skin test (Prick test) negative to Dp, Ds and Bt, and without a previous Cardiorespiratory Polygraphy (CRP) were discarded, leaving 236 patients between 8 and 70 years old: 102 cases (43.2 percent) those with oral breathing and snoring and 134 controls (56.7 percent) without oral breathing or snoring. The CRP data analysis was performed using the automatic algorithm of the ApneaLink AirTM device (Resmed Corp., Germany). The average size of the wheal was 5.9 mm in cases (p = 0.02). The Apnea Hypopnea Index (AHI) was greater than 5 events/hour in 129 patients (54.6 percent); of those, 97 cases (41.1 percent) and 32 controls (13.5 percent). Patients with AHI˃20/h predominated in cases with 21 individuals (8.8 percent) (p꞊0.048). The sensitivity of the PCR was 95.10 percent, its specificity 76.12 percent. The positive and negative predictive values were 75.19 percent and 95.33 percent respectively. The positive likelihood ratio was 3.98 and the negative one was 0.06. The prevalence of OSAHS was significantly higher in cases compared to controls (p =0.002). The CRP with the ApneaLink device allows the diagnosis of SAHOS in AR(AU)

Prevalence of gene rearrangements in Mexican children with acute lymphoblastic leukemia: a population study-report from the Mexican Interinstitutional Group for the identification of the causes of childhood leukemia.

Mexico has one of the highest incidences of childhood leukemia worldwide and significantly higher mortality rates for this disease compared with other countries. One possible cause is the high prevalence of gene rearrangements associated with the etiology or with a poor prognosis of childhood acute lymphoblastic leukemia (ALL). The aims of this multicenter study were to determine the prevalence of the four most common gene rearrangements [ETV6-RUNX1, TCF3-PBX1, BCR-ABL1, and MLL rearrangements] and to explore their relationship with mortality rates during the first year of treatment in ALL children from Mexico City. Patients were recruited from eight public hospitals during 2010-2012. A total of 282 bone marrow samples were obtained at each child's diagnosis for screening by conventional and multiplex reverse transcription polymerase chain reaction to determine the gene rearrangements. Gene rearrangements were detected in 50 (17.7%) patients. ETV6-RUNX1 was detected in 21 (7.4%) patients, TCF3-PBX1 in 20 (7.1%) patients, BCR-ABL1 in 5 (1.8%) patients, and MLL rearrangements in 4 (1.4%) patients. The earliest deaths occurred at months 1, 2, and 3 after diagnosis in patients with MLL, ETV6-RUNX1, and BCR-ABL1 gene rearrangements, respectively. Gene rearrangements could be related to the aggressiveness of leukemia observed in Mexican children.

Lack of evidence for human T-lymphotropic virus type 1 and mouse mammary tumor-like virus involvement in the genesis of childhood acute lymphoblastic leukemia.

BACKGROUND: In Mexico City, the incidence of childhood acute lymphoblastic leukemia (ALL) is one of the highest in the world; epidemiologic evidence suggests that infectious agents could be involved in the genesis of this disease. Early transmitted oncogenic retroviruses infecting lymphocytes are important candidates. METHODS: PCR-based assays were used to screen viral genomic sequences of human T-cell lymphotrophic virus, type 1 (HTLV1) and mouse mammary tumor virus (MMTV)-like virus (MMTV-LV) in leukemic cells from 67 pediatric patients with ALL. RESULTS: Viral genomic sequences were not detected in any sample by neither standard nor nested PCR. CONCLUSIONS: Because of the methodologic strictness and high statistical power of the study, these results suggest that HTLV1 and MMTV-LV are not involved in the genesis of childhood ALL in Mexican children. IMPACT: To our knowledge, this is the first work exploring the direct participation of HTLV1 and MMTV-LV retroviruses in childhood ALL development.

The age incidence of childhood B-cell precursor acute lymphoblastic leukemia in Mexico City.

The objective of this population-based survey was to assess the peak age of incidence of B-cell precursor acute lymphoblastic leukemia (ALL) in children in Mexico City (MC). All patients were classified according to their immunophenotype, and only B-cell precursor and T-lineage were analyzed. Rates of incidence were calculated x10 children. Of the 364 children from MC who were included in this study, immunophenotyping had been performed for 81.6%. The frequency of B-cell precursor ALL was 76.1%, whereas T lineage ALL showed a frequency of 23.6%. Peak age for ALL was 2 to 3 years of age. B-cell precursor ALL was the major contributor to peak age; T lineage ALL showed a peak among 1 and 3 years of age. We conclude that the age peak for children with ALL in MC is within the ranges reported for developed countries and that B-cell precursor ALL is the main contributor to these peak.

Utilidad de la proteína C reactiva para el diagnóstico de infección bacteriana en el paciente pediátrico con cáncer, fiebre y neutropenia / Usefulness of C-reactive protein in the diagnosis of bacterial infection in the pediatric patient with cancer, fever and neutropenia

Introducción. El diagnóstico de infección bacteriana en el paciente con cáncer, fiebre y neutropenia se dificulta debido a una pobre respuesta inflamatoria. Se han realizado evaluaciones con reactantes de fase aguda, como la proteína C reactiva, con resultados variables. El objetivo de este trabajo fue calcular la sensibilidad, especificidad, valores predictivos positivos y negativos y razones de verosimilitud de la proteína C reactiva para el diagnóstico de infección bacteriana en pacientes con cáncer y neutropenia febril. Métodos. Se realizó el estudio de la prueba diagnóstica. Se incluyeron pacientes pediátricos con cáncer, y neutropenia (<500 NA/mm³). La proteína C reactiva se cuantificó por nefelometría. Los episodios se clasificaron en cuatro grupos: grupo I, infección microbiológicamente documentada; grupo II, infección clínicamente documentada; grupo III, fiebre por otras causas; y grupo IV, pacientes con neutropenia sin fiebre. Se realizó el cálculo de sensibilidad, especificidad, valores predictivos positivos y negativos, curvas operantes del receptor y razones de verosimilitud. Para la comparación de variables cuantitativas se emplearon la U de Mann-Whitney y Kruskal-Wallis y para variables cualitativas, χ². Resultados. Se incluyeron 127 episodios que se distribuyeron en: 29, 47, 20 y 31 episodios para los grupos I, II, III y IV, respectivamente. Las medianas de la proteína C reactiva fueron 282 mg/L para el grupo I, 205 mg/L grupo II, 27.3 mg/L grupo III y 5.1 mg/L para el grupo IV (p < 0.001). Con la proteína C reactiva de 60 mg/L se obtuvo una sensibilidad de 94%, especificidad de 94%, valor predictivo positivo 96% y valor predictivo negativo 92%; razón de verosimilitud para un resultado positivo 15.6 y de 0.06 para resultado negativo. Conclusiones. La proteína C reactiva es una prueba útil y económica para el diagnóstico de infección bacteriana en el paciente con cáncer, fiebre y neutropenia.

Background. Diagnosis of bacterial infection in the patient with cancer, fever and neutropenia is difficult due to the poor inflammatory response. Several evaluations of acute phase reactants such as C-reactive protein (C-RP) have been performed with diverse results. The aim of this study was to calculate the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), and likelihood ratios (LR) for C-RP in the diagnosis of bacterial infection of patients with cancer, neutropenia and fever. Methods. We carried out a diagnostic test study. Pediatric patients with cancer and neutropenia (<500 NA/mm³) were selected. C-RP was determined by nephelometry. Episodes were classified into the following groups: group I: microbiologically documented infection; group II: clinically documented infection; group III: fever of unknown origin; group IV: patients with neutropenia without fever. Sensitivity, specificity, PPV, NPV, receiving operating curves (ROC) and LR were calculated. Mann-Whitney U test and Kruskal-Wallis test were used for comparison of quantitative variables. For qualitative variables, χ2 test was used. Results. There were 127 episodes distributed as follows: 29, 47, 20 and 31 for groups I, II, III and IV, respectively. Median of C-RP values were 282 mg/L for group I, 205 mg/L group II, 27.3 mg/L group III and 5.1 mg/L group IV (p <0.001). With a C-RP value of 60 mg/L, we obtained a sensitivity of 94%, specificity 94%, PPV 6% and NPV 92%. LR for a positive test was 15.6 and LR for a negative test was 0.06. Conclusions. C-RP is a useful and economically feasible test for diagnosis of bacterial infection in patients with cancer, neutropenia and fever.

Incidencia de las leucemias agudas en niños de la ciudad de México, de 1982 a 1991 / Incidence of acute leukemia in children of Mexico city; 1982 to 1991

Objetivo. Medir la tasa de incidencia de las leucemias agudas (LA) en las diferentes delegaciones políticas del Distrito Federal y evaluar si existe una tendencia significativa en dichos padecimientos en tales delegaciones. Material y métodos. Estudio longitudinal descriptivo realizado en seis hospitales de la ciudad de México, los que atienden a cerca de 97.5 por ciento de todos los niños con cáncer de esta ciudad. Los datos se capturaron de 1995 a 1996, y se analizaron en 1999, en el Hospital de Pediatría del Centro Médico Nacional Siglo XXI, del Instituto Mexicano del Seguro Social. Para cada delegación se cal-cularon la tasa de incidencia anual promedio, la tasa es-tandarizada y la razón estandarizada de morbilidad (REM) con intervalos de confianza al 95 por ciento (IC 95 por ciento). La tendencia se evaluó con la tasa de cambio promedio. Re-sultados. Se observó una tendencia al incremento en la incidencia de la leucemia aguda linfoblástica (LAL) en cinco delegaciones: Alvaro Obregón, Cuauhtémoc, Gustavo A. Madero, Izta-calco y Venustiano Carranza. En la leucemia aguda mieloblás-tica (LAM) no se notificaron cambios estadísticamente signi-ficativos en la incidencia en ninguna delegación política. Sólo con LAM se encontró una REM significativa y co-rrespondió a la delegación Alvaro Obregón (REM= 2.91, IC 95 por ciento 1.63 - 4.80). Las REM más altas se encontraron en el sur y suroeste de la ciudad. Conclusiones. Sólo se observó incremento en la incidencia de LAL en cinco delegaciones políticas. La incidencia más alta de LAM se encontró en la delegación Alvaro Obregón.

Proteinuria secundaria a hiperproteinemia inducida por transfusiones de plasma. / Proteinuria secondary to hyperproteinemia induced by plasma infusions

En general se reconocen dos mecanismos principales de produccion de proteinuria: incremento de la permeabilidad glomerular y reduccion de la resorcion tubular renal.Sin embargo, existe un tercer mecanismo que consiste en paso aumentado de proteinas por el filtro glomerular normal, a consecuencia de incremento en su concentracion serica. A este ultimo respecto se describe el caso de un nino con enfermedad de Christmas que desarrollo proteinuria masiva secundaria a hiperproteinemia inducida por transfusiones multiples de plasma. La proteinuria desaparecio al suspenderse estas transfusiones

Respuesta al tratamiento en ninos con purpura trombocitopenica idiopatica cronica. / Response to the treatment in children with chronic idiopathic thrombocytopenic purpura

Se estudiaron 63 ninos con purpura trombocitopenica idiopatica cronica (PTIC), 39 de los cuales eran del sexo femenino. Todos los pacientes recibieron al inicio tratamiento con prednisona, y se produjo respuesta en quetopenia en seis (9 por ciento) de ellos. Por la persistencia de la plaquetopenia se practico esplenectomia a 55 pacientes y ocurrio remision en 34 (62 por ciento) de los casos. En los 21 pacientes restantes se indico nuevamente tratamiento con prednisona, y se produjo reaccion en otros seis (28 por ciento) casos. Una paciente fallecio por complicacion infecciosa. Los 14 pacientes que no respondieron a las medidas terapeuticas anteriores se sometieron a tratamiento con agentes inmunosupresores sin efecto favorable manifiesto. Los resultados de este estudio indican que la esplenectomia continua siendo el tratamiento de eleccion en ninos con PTIC que experimentan plaquetopenia grave y persistente. Los ninos que no responden a la esplenectomia tienden a reaccionar a un nuevo tratamiento con dosis bajas de corticosteroides

Un instrumento para medir la calidad de vida por medio del desempeño diario en pacientes pediátricos con leucemia / An instrumen for measuring the quality of life through daily work with pediatric leukemic patients

Objetivo: determinar la validez de un instrumento para evaluar el estado funcional de pacientes pediátricos con leucemia, como indicador de calidad de vida. Material: se diseñó un cuestionario de las actividades de la vida diario del niño de acuerdo a los criterios de Lickert, el cual fue cometido a un estudio piloto con pacientes sin enfermedad crónica ni incapacitante. El resultado se correlacionó con la impresión clínica del cuestionario a 60 pacientes, en 15 de los cuales se evaluó la consistencia. Resultados: se aplicó el cuestionario a 60 pacientes. veintinueve femeninos y 31 masculinos, se encontró en remisión 15 por ciento con recaída y 8 por ciento en inducción a la remisión. El intervalo de edad fue de 2 a 16 años con una media de 9 ñ 3.6 años. En forma global, el 100 por ciento de los pacientes obtuvo calificación satisfactoria, mayor a 35 puntos. El área escolar fue la más afectada ni con la fase del tratamiento. La correlación entre el médico tratante con las del cuestionario fue de 100 por ciento. El instrumento mostró consistencia. Conclusiones: el cuestionario identificó adecua-damente el nivel de desempeño diario de los pacientes con leucemia, así como áreas específicas en las cuales se encuentra alterado el desempeño. El nivel de desempeño de los pacientes pediátricos con leucemia es adecuado.