Intranasal neomycin evokes broad-spectrum antiviral immunity in the upper respiratory tract.

Respiratory virus infections in humans cause a broad-spectrum of diseases that result in substantial morbidity and mortality annually worldwide. To reduce the global burden of respiratory viral diseases, preventative and therapeutic interventions that are accessible and effective are urgently needed, especially in countries that are disproportionately affected. Repurposing generic medicine has the potential to bring new treatments for infectious diseases to patients efficiently and equitably. In this study, we found that intranasal delivery of neomycin, a generic aminoglycoside antibiotic, induces the expression of interferon-stimulated genes (ISGs) in the nasal mucosa that is independent of the commensal microbiota. Prophylactic or therapeutic administration of neomycin provided significant protection against upper respiratory infection and lethal disease in a mouse model of COVID-19. Furthermore, neomycin treatment protected Mx1 congenic mice from upper and lower respiratory infections with a highly virulent strain of influenza A virus. In Syrian hamsters, neomycin treatment potently mitigated contact transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In healthy humans, intranasal application of neomycin-containing Neosporin ointment was well tolerated and effective at inducing ISG expression in the nose in a subset of participants. These findings suggest that neomycin has the potential to be harnessed as a host-directed antiviral strategy for the prevention and treatment of respiratory viral infections.

Adult Height in Girls With Idiopathic Premature Adrenarche: A Cohort Study and Design of a Predictive Model.

Introduction: Idiopathic premature adrenarche (IPA) is considered a normal variant of puberty, presenting more commonly in female patients. There are concerns as to whether IPA alters the final height of these girls. Our main objectives were to (a) compare the adult height of girls with IPA against their target height and (b) design a mathematical model to predict adult height at diagnosis in female patients with IPA. Materials and Methods: A cohort study of girls with IPA was conducted from the time of IPA diagnosis until adult height. The following data were collected: target height, perinatal history, anthropometric and biochemical variables and bone age at diagnosis, age at Tanner stage 2 and menarcheal age, and adult height. First, we performed a univariate statistical analysis after which we carried out a multiple linear regression analysis using adult height as the dependent variable. Results: We obtained data from 79 female patients diagnosed with IPA with a mean adult height of 164.6 cm (95% CI: 163.36-165.85 cm). The mean follow-up time was 6.60 years. Average age at Tanner stage 2 was 9.71 years. Mean menarcheal age was 11.64 years. There were no significant differences between target height and adult height. Of the several predictive models designed for these patients, one of them, which included bone age, obtained an R2 value of 71%. Conclusions: Although slightly advanced puberty was observed among the girls with IPA, their adult height was preserved. The use of predictive models of adult height on diagnosis of IPA could facilitate closer follow-up of girls at risk of reduced adult height.

A stem-loop RNA RIG-I agonist protects against acute and chronic SARS-CoV-2 infection in mice.

As SARS-CoV-2 continues to cause morbidity and mortality around the world, there is an urgent need for the development of effective medical countermeasures. Here, we assessed the antiviral capacity of a minimal RIG-I agonist, stem-loop RNA 14 (SLR14), in viral control, disease prevention, post-infection therapy, and cross-variant protection in mouse models of SARS-CoV-2 infection. A single dose of SLR14 prevented viral infection in the lower respiratory tract and development of severe disease in a type I interferon (IFN-I)-dependent manner. SLR14 demonstrated remarkable prophylactic protective capacity against lethal SARS-CoV-2 infection and retained considerable efficacy as a therapeutic agent. In immunodeficient mice carrying chronic SARS-CoV-2 infection, SLR14 elicited near-sterilizing innate immunity in the absence of the adaptive immune system. In the context of infection with variants of concern (VOCs), SLR14 conferred broad protection against emerging VOCs. These findings demonstrate the therapeutic potential of SLR14 as a host-directed, broad-spectrum antiviral for early post-exposure treatment and treatment of chronically infected immunosuppressed patients.

Trends in the Use of Anxiolytics in Castile and Leon, Spain, between 2015-2020: Evaluating the Impact of COVID-19.

Anxiolytics (N05B) are one of the most widely used pharmacological groups. This study aimed to analyze the progression of the consumption of anxiolytics (ATC classification: N05B) dispensed in pharmacies in Castile and Leon, Spain, from 2015 to 2020, with a special focus on the possible impact of COVID-19 on the use of these drugs. A quantitative-qualitative analysis of usage was carried out using the total number of packs and the packs per 1000 inhabitants. Overall, the use of anxiolytics grew by 14.41% during 2015-2020. The most commonly used drugs were the short-acting benzodiazepine derivatives lorazepam (whose use increased by 15.18%) and alprazolam (whose use increased by 21.40%), and the dispensing of the long-acting derivative diazepam increased the most, by 31.83%. Anxiolytics consumption increased significantly in 2020 and peaked in March. The pattern of use remained the same in 2020. The consumption of anxiolytics has continued to increase in Castile and Leon over the last six years. The COVID-19 pandemic situation affected the dispensing of these drugs, causing a sharp increase in prescriptions, especially during March, when the confinement of the population was initiated.

Streptomyces sp. M54: an actinobacteria associated with a neotropical social wasp with high potential for antibiotic production.

Streptomyces symbionts in insects have shown to be a valuable source of new antibiotics. Here, we report the genome sequence and the potential for antibiotic production of "Streptomyces sp. M54", an Actinobacteria associated with the eusocial wasp, Polybia plebeja. The Streptomyces sp. M54 genome is composed of a chromosome (7.96 Mb), and a plasmid (1.91 Kb) and harbors 30 biosynthetic gene clusters for secondary metabolites, of which only one third has been previously characterized. Growth inhibition bioassays show that this bacterium produces antimicrobial compounds that are active against Hirsutella citriformis, a natural fungal enemy of its host, and the human pathogens Staphylococcus aureus and Candida albicans. Analyses through TLC-bioautography, LC-MS/MS and NMR allowed the identification of five macrocyclic ionophore antibiotics, with previously reported antibacterial, antitumor and antiviral properties. Phylogenetic analyses placed Streptomyces sp. M54 in a clade of other host-associated strains taxonomically related to Streptomyces griseus. Pangenomic and ANI analyses confirm the identity of one of its closest relatives as Streptomyces sp. LaPpAH-199, a strain isolated from an ant-plant symbiosis in Africa. In summary, our results suggest an insect-microbe association in distant geographic areas and showcase the potential of Streptomyces sp. M54 and related strains for the discovery of novel antibiotics.

Intestinal Gel-Forming Mucins Polymerize by Disulfide-Mediated Dimerization of D3 Domains.

The mucin 2 glycoprotein assembles into a complex hydrogel that protects intestinal epithelia and houses the gut microbiome. A major step in mucin 2 assembly is further multimerization of preformed mucin dimers, thought to produce a honeycomb-like arrangement upon hydrogel expansion. Important open questions are how multiple mucin 2 dimers become covalently linked to one another and how mucin 2 multimerization compares with analogous processes in related polymers such as respiratory tract mucins and the hemostasis protein von Willebrand factor. Here we report the x-ray crystal structure of the mucin 2 multimerization module, found to form a dimer linked by two intersubunit disulfide bonds. The dimer structure calls into question the current model for intestinal mucin assembly, which proposes disulfide-mediated trimerization of the same module. Key residues making interactions across the dimer interface are highly conserved in intestinal mucin orthologs, supporting the physiological relevance of the observed quaternary structure. With knowledge of the interface residues, it can be demonstrated that many of these amino acids are also present in other mucins and in von Willebrand factor, further indicating that the stable dimer arrangement reported herein is likely to be shared across this functionally broad protein family. The mucin 2 module structure thus reveals the manner by which both mucins and von Willebrand factor polymerize, drawing deep structural parallels between macromolecular assemblies critical to mucosal epithelia and the vasculature.

Estudio de la asociación de adrenarquia prematura idiopática con la presencia de alteraciones metabólicas y con antecedente de pequeño para edad gestacional / The relationship between metabolic disorders and small for gestational age with idiopathic premature adrenarche

Introducción: Hasta la fecha hay datos contradictorios sobre la relación entre adrenarquia prematura idiopática (API) y el antecedente de pequeño para edad gestacional así como con la presencia de obesidad y otras alteraciones metabólicas. Es nuestra intención estudiar esa posible asociación en una cohorte de niñas con API de nuestro hospital. Pacientes y métodos: Estudio descriptivo transversal que incluyó a niñas diagnosticadas de API en el servicio de Pediatría de la Fundación Jiménez Díaz entre enero de 2007 y mayo de 2015. Se recogieron datos sobre antecedentes familiares, antecedentes personales que incluían datos perinatales así como datos antropométricos y datos bioquímicos al diagnóstico. Resultados: Del total de 76 niñas con API, un 2,7% presentaba antecedente de pequeño para edad gestacional. Utilizando la clasificación del índice de masa corporal según criterios modificados de OMS 2007/Cole 2000, un 11,8% tenían sobrepeso y un 11,8% obesidad al diagnóstico. Según los criterios del Ministerio de Sanidad, un 6,6% presentaban sobrepeso y un 18,4% obesidad. Un 21,2% evidenciaron insulinorresistencia y un 13,95% presentaban dislipidemia. Ninguna de las pacientes cumplía criterios de hipertensión arterial. En el análisis comparativo entre niñas con API que presentaban normopeso frente a las que tenían sobrepeso y obesidad, las segundas presentaban niveles significativamente más elevados de triglicéridos e insulina y más bajos de colesterol HDL. Conclusiones: Las niñas con API estudiadas no presentan mayor porcentaje de pequeño para edad gestacional que la población general. La prevalencia de sobrepeso y obesidad entre las niñas con API no es superior a la de la población de su entorno (AU)

Background: There is still controversy on the relationship between idiopathic premature adrenarche (IPA) and a history of small for gestational age, as well as the concomitant presence of obesity and other metabolic disturbances. An attempt is made to study these potential associations in a cohort of girls with IPA from our hospital. Patients and methods: A descriptive cross-sectional study was conducted that included girls with a diagnosis of IPA from the Paediatric Department of the Fundación Jiménez Díaz (Madrid, Spain) between January 2007 and May 2015. A record was made of family and personal history with perinatal data, as well as anthropometric data and biochemical values at the time of diagnosis. Results: Out of a total of 76 girls with IPA, 2.7% had a history of small for gestational age. When body mass index was analysed according to modified criteria of WHO 2007/Cole 2000, 11.8% were overweight, and 11.8% were obese at diagnosis. Using the criteria set by the Spanish Ministry of Health, 6.6% were overweight and 18.4% obese, with 21.2% of the girls being insulin resistance, and 13.95% having dyslipidaemia. None of them had hypertension. From a comparative analysis between normal and overweight and obesity IPA girls, the latter had significantly higher levels of triglycerides and insulin, a higher HOMA index, and lower levels of HDL cholesterol. Conclusions: IPA girls included in the study do not have a higher prevalence of small for gestational age compared to the general population. Prevalence of overweight and obesity in girls with IPA is not higher than the prevalence in the normal population (AU)

[The relationship between metabolic disorders and small for gestational age with idiopathic premature adrenarche]. / Estudio de la asociación de adrenarquia prematura idiopática con la presencia de alteraciones metabólicas y con antecedente de pequeño para edad gestacional.

BACKGROUND: There is still controversy on the relationship between idiopathic premature adrenarche (IPA) and a history of small for gestational age, as well as the concomitant presence of obesity and other metabolic disturbances. An attempt is made to study these potential associations in a cohort of girls with IPA from our hospital. PATIENTS AND METHODS: A descriptive cross-sectional study was conducted that included girls with a diagnosis of IPA from the Paediatric Department of the Fundación Jiménez Díaz (Madrid, Spain) between January 2007 and May 2015. A record was made of family and personal history with perinatal data, as well as anthropometric data and biochemical values at the time of diagnosis. RESULTS: Out of a total of 76 girls with IPA, 2.7% had a history of small for gestational age. When body mass index was analysed according to modified criteria of WHO 2007/Cole 2000, 11.8% were overweight, and 11.8% were obese at diagnosis. Using the criteria set by the Spanish Ministry of Health, 6.6% were overweight and 18.4% obese, with 21.2% of the girls being insulin resistance, and 13.95% having dyslipidaemia. None of them had hypertension. From a comparative analysis between normal and overweight and obesity IPA girls, the latter had significantly higher levels of triglycerides and insulin, a higher HOMA index, and lower levels of HDL cholesterol. CONCLUSIONS: IPA girls included in the study do not have a higher prevalence of small for gestational age compared to the general population. Prevalence of overweight and obesity in girls with IPA is not higher than the prevalence in the normal population.

Variations in serum magnesium and hormonal levels during incremental exercise.

In this study, we examined the relationship between plasma magnesium levels and hormonal variations during an incremental exercise test until exhaustion in 27, well-trained, male endurance athletes. After a warm-up of 10 min at 2 W/kg, the test began at an initial workload of 2.5 W/kg and continued with increments of 0.5 W/kg every 10 min until exhaustion. Plasma magnesium, catecholamine, insulin, glucagon, parathyroid hormone (PTH), calcitonin, aldosterone and cortisol levels were determined at rest, at the end of each stage and three, five and seven minutes post-exercise. With the incremental exercise test, no variations in plasma magnesium levels were found, while plasma adrenaline, noradrenaline, PTH, glucagon and cortisol levels increased significantly. Over the course of the exercise, plasma levels of insulin decreased significantly, but those of calcitonin remained steady. During the recovery period, catecholamines and insulin returned to basal levels. These findings indicate that the magnesium status of euhydrated endurance athletes during incremental exercise testing may be the result of the interrelation between several hormonal variations.

Características psicopatológicas de un grupo de adolescentes con obesidad que ingresa a un programa de terapia nutricional / Psychopathological characteristics of a group of adolescents with obesity that entered into a nutritional therapy program

La obesidad es actualmente el principal problema nutricional de la población chilena. Afecta a un 32 por ciento de los adolescentes y se ha asociado con: discriminación, baja autoestima, matonaje escolar, dificultades sociales, fracaso escolar y comorbilidad de salud mental (hasta un 58 por ciento, principalmente manifestaciones internalizantes). Son escasos los estudios de personalidad en población infantojuvenil con obesidad, encontrándose asociaciones con narcisismo y descontrol de impulsos. Dado que la personalidad es un determinante profundo de pensamientos y comportamiento, esperamos que el estudio de la personalidad nos entregue una mejor comprensión de la obesidad. Nuestro objetivo es describir la psicopatología y rasgos de personalidad en un grupo de adolescentes mujeres con obesidad que ingresan a tratamiento nutricional. Se realizó un estudio clínico descriptivo y transversal, de 22 pacientes de sexo femenino, entre 13 y 19 años que ingresaron a tratamiento en dos centros del Departamento Oriente de la Facultad de Medicina de la Universidad de Chile. Se aplicó a las participantes una entrevista estructurada (MINI- Kids) para evaluar diagnósticos del Eje I y un test autoaplicado para evaluar características de personalidad (MACI, validado para población adolescente chilena y utilizado en estudios previos). Los resultados derivados de la aplicación del MACI se observó que el 68,2 por ciento de las pacientes evaluadas presentó rasgos de personalidad “prominentes”, y de este grupo el rasgo más frecuentemente encontrado corresponde a “Egocéntrico”, seguido por los rasgos “Histriónico”, “Rudo” y “Conformista”. Se evaluaron además los rasgos más frecuentes que se presentaban bajo el corte mínimo, los cuales fueron: tendencia límite (10 pacientes), introversión y autopunitivo (8 pacientes) e inhibido (7 pacientes)...

Obesity is the main nutritional problem of Chilean population, being 32 percent of chilean adolescents obese. It has been associated with: discrimination, low self-esteem, bullying, social difficulties, school failure and mental health comorbidity (up to 58 percent, mainly internalizing events). There are only a few studies about personality in obese children and adolescents, and those studies have found associations with narcissism and impulsivity. Given that personality is deep determinant in thoughts and behavior, we expect that the study of personality would give us a better understanding of obesity. Our main target is to describe the psychopathology and personality traits in a group of female adolescents with obesity that entered into nutritional treatment. We conducted a descriptive clinical study of 22 female patients between 13 and 19 years old who iniciated treatment in two centers from the East Department of the University of Chile Medical School. A structured interview (MINI-Kids) was applied to the participants to evaluate Axis I diagnoses, and a self-administered test was used to evaluate personality characteristics (MACI, validated in chilean adolescents, used in previous studies). In the results from the implementation of MACI test we observed that 68.2 percent of patients showed “prominent” traits, and from this group the most frequent feature founded was “Egotistic” followed by the features “Dramatizing”, “Unruly” and “Conforming” We also evaluated the traits that were presented under the lower limit, which were: borderline tendency (10 patients), introversive and self-demeaning (8 patients) and inhibited (7 patients). In addition 77.3 percent of the patients studied met criteria for at least one Axis I diagnosis (17 adolescents), half of them with a depressive disorder and 45 percent with comorbidity. The patients studied have features in common, and this work presents a first approach from the child and adolescent mental health...

Optical system design for orthosymplectic transformations in phase space.

On the basis of a matrix formalism, we analyze the paraxial optical systems composed by generalized lenses and fixed free-space intervals, suitable for orthosymplectic transformations in phase space. Flexible configurations to perform the attractive operations for optical information processing such as image rotation, separable fractional Fourier transformation, and twisting for different parameters are proposed.

Fourier series analysis of fractal lenses: theory and experiments with a liquid-crystal display.

We report on a Fourier series approach that predicts the focal points and intensities produced by fractal zone plate lenses. This approach allows us to separate the effects of the fractal order from those of the lens aperture. We implement these fractal lenses onto a liquid-crystal display and show experimental verification of our theory.

Focusing properties of fractal zone plates: experimental implementation with a liquid-crystal display.

We report the first experimental results, to our knowledge, with fractal zone plates implemented in a liquid-crystal display. Our results largely agree with theory for the axial irradiance distribution of these lenses. The dependence of the shape and size of the focus points on critical design parameters is discussed. Additional unpredicted features are also described.

Importance of the phase and amplitude in the fractional Fourier domain.

The importance of the amplitude and phase in the fractional Fourier transform (FT) domain is analyzed on the basis of the rectangular signal and the real-world image. The quality of signal restoration from only the amplitude or from only the phase of its fractional FT by applying the inverse fractional FT is considered. It is shown that the signal reconstructed from the amplitude of the fractional FT usually reveals the main features of the original signal only for relatively low fractional orders. On the basis of phase information in the fractional FT domains, significant details of the signal can be obtained for nearly all fractional orders.

Lesión de dieulafoy una causa oculta de sangrado gastrointestinal: presentación de un caso y revisión de la literatura / Injuries of dieulafoy cause occulta of gastroientestinal hemorrhage: presentation of a case and review of the literature

Se presenta el caso de un paciente de sexo masculino, de 80 años de edad con Hemorragia Digestiva Superior recurrente no masiva de origen oculto, descubriéndose Lesión de Dieulafoy posterior a un episodio de Hemorragia Digestiva Mesiva, tratada exitosamente con Esclerosis. Se hace hincapié en la necesidad de realizar Endoscopia de dichas lesiones y su importancia como herramienta de diagnóstico y control post-esclerosis. La resección precisa en cuña de este caso, fue precedida de tatuaje de la zona de esclerosis ya estudiada por Eco-endoscopia. Un control al año ha demostrado ausencia de recurrencia

Valores normales de alfa feto proteína por ensayo inmunorradiométrico durante el primer año de vida / Alpha fetoprotein reference levels during the first year of life

El propósito de este estudio fue determinar la variación de los niveles séricos de alfa fetoproteína (AFP), durante el primer año de vida, utilizando un ensayo inmunorradiométrico. Se realizó la estadística descriptiva en cada período estudiado. Se determinó el tipo de correlación existente entre la AFP sérica y el tiempo. Durante el primer mes de vida se observó una correlación lineal: r = - 0,957; mientras que entre el 2º y 12º mes los datos se ajustaron a una potencial de la forma y = axb : r = 0,989. Los niveles promedios de AFP al primer año de vida fueron similares a los del adulto normal, no obstante un 10 por ciento de los niños estudiados presentó valores más elevados. Los rangos de normalidad obtenidos permitiran una mejor discriminación entre normales y patológicos, cuando sea necesaria la utilización de AFP como un elemento más para diagnosticar neoplasias embrionarias, en la etapa de vida estudiada

Valores normales de alfa feto proteína por ensayo inmunorradiométrico durante el primer año de vida / Alpha fetoprotein reference levels during the first year of life

El propósito de este estudio fue determinar la variación de los niveles séricos de alfa fetoproteína (AFP), durante el primer año de vida, utilizando un ensayo inmunorradiométrico. Se realizó la estadística descriptiva en cada período estudiado. Se determinó el tipo de correlación existente entre la AFP sérica y el tiempo. Durante el primer mes de vida se observó una correlación lineal: r = - 0,957; mientras que entre el 2º y 12º mes los datos se ajustaron a una potencial de la forma y = axb : r = 0,989. Los niveles promedios de AFP al primer año de vida fueron similares a los del adulto normal, no obstante un 10 por ciento de los niños estudiados presentó valores más eleva

Cresimiento y metabolismo del calcio en ratas sometidas a intoxicación crónica con hidróxido de aluminio / Growth and metabolism of calcio in rats chronically poisoned with aluminium hydroxide

Se estudiaron los efectos del aluminio sobre el crecimiento y desarrollo corporal, entre la 3 y 26 semanas de edad, en ratas intoxicadas crónicamente con hidróxido de aluminio (80 mg/kg peso ûi.p.- 3 veces por semana) y en ratas controles. El crecimiento fue evaluado de acuerdo a la teorfa de Parks de alimentación y crecimiento. El metabolismo del calcio al finalizar el perfodo de intoxicación, se estudió a través de un balance de calcio y la determinación de la velocidad de deposición y resorción ósea con ayuda de (45)Ca. Se examinó la función de la glándula paratiroides por un método indirecto. Se observó una disminución del peso corporal, sin afectarse la ingesta de alimento. El grupo tratado con aluminio se carcterizó por una reducción en la eficiencia inicial de conversión de alimento en biomasa. El aluminio no afectó la velocidad de crecimiento, ni el tiempo necesario para alcanzar la madurez. El balance de calcio en las ratas tratadas fue significativamente menor que en el grupo control. Esto fue acompañado de un aumento significativo del calcio excretado por heces, causado quizás por una menor absorción intestinal. Se observaron depósitos importantes de aluminio en la superficie del hueso trabecular y una disminución en la masa de calcio óseo en las ratas tratadas, no obstante no existen diferencias de esta última al ser expresada por 100 gr de peso corporal. La velocidad de deposición de Ca++ óseo disminuyó por efecto del aluminio, sin existir modificaciones en la velocidad de resorción ósea. La reducción del turnover óseo, reflejado por la disminución de Vo+/Vo-, fue acompañado por una menor velocidad en la recuperación de la calcemia, dato vinculado indirectamente a la respuesta de la glándula paratiroides a la hipocalcemia. En el modelo estudiado, la reducción del turnover óseo podrfa estar originado por los depósitos de aluminio en hueso, no obstante podrfan existir factores asociados como una disfunción en la secreción de PTH, o bien disminución de la afinidad en sus receptores a nivel óseo.

Cresimiento y metabolismo del calcio en ratas sometidas a intoxicación crónica con hidróxido de aluminio / Growth and metabolism of calcio in rats chronically poisoned with aluminium hydroxide

Se estudiaron los efectos del aluminio sobre el crecimiento y desarrollo corporal, entre la 3 y 26 semanas de edad, en ratas intoxicadas crónicamente con hidróxido de aluminio (80 mg/kg peso ¹i.p.- 3 veces por semana) y en ratas controles. El crecimiento fue evaluado de acuerdo a la teorfa de Parks de alimentación y crecimiento. El metabolismo del calcio al finalizar el perfodo de intoxicación, se estudió a través de un balance de calcio y la determinación de la velocidad de deposición y resorción ósea con ayuda de (45)Ca. Se examinó la función de la glándula paratiroides por un método indirecto. Se observó una disminución del peso corporal, sin afectarse la ingesta de alimento. El grupo tratado con aluminio se carcterizó por una reducción en la eficiencia inicial de conversión de alimento en biomasa. El aluminio no afectó la velocidad de crecimiento, ni el tiempo necesario para alcanzar la madurez. El balance de calcio en las ratas tratadas fue significativamente menor que en el grupo control. Esto fue acompañado de un aumento significativo del calcio excretado por heces, causado quizás por una menor absorción intestinal. Se observaron depósitos importantes de aluminio en la superficie del hueso trabecular y una disminución en la masa de calcio óseo en las ratas tratadas, no obstante no existen diferencias de esta última al ser expresada por 100 gr de peso corporal. La velocidad de deposición de Ca++ óseo disminuyó por efecto del aluminio, sin existir modificaciones en la velocidad de resorción ósea. La reducción del turnover óseo, reflejado por la disminución de Vo+/Vo-, fue acompañado por una menor velocidad en la recuperación de la calcemia, dato vinculado indirectamente a la respuesta de la glándula paratiroides a la hipocalcemia. En el modelo estudiado, la reducción del turnover óseo podrfa estar originado por los depósitos de aluminio en hueso, no obstante podrfan existir factores asociados como una disfunción en la secreción de PTH, o bien disminución de la afinidad en sus receptores a nivel óseo. (AU)