Abstract The increase in world population and the demand for technologies have exponentially increased the consumption of mineral resources, putting their availability for future generations at risk. The objective of this study is to know the state of academic production on resource scarcity and evaluate its consequences on exploitation, sustainability and technological development. A systematized bibliographic review was developed using the Scopus, WoS and SciELO databases. 57 documents were analyzed that cover topics such as the environmental impact of extraction, reuse strategies, criticality evaluations and regulatory policies for mining activity. It is concluded that the main factors of resource scarcity are related to the lack of regulations, the growing demand for new technologies and discrepancy in criticality estimation methods. There is a need to look for extraction alternatives and promote material recovery strategies.

Resumen El incremento de la población mundial y la demanda de tecnologías han aumentado de manera exponencial el consumo de recursos minerales, poniendo en riesgo su disponibilidad para las generaciones futuras. El presente estudio tiene como objetivo conocer el estado de la producción académica sobre la escasez de recursos y evaluar sus consecuencias en la explotación, la sostenibilidad y el desarrollo tecnológico. Se llevó a cabo una revisión bibliográfica sistematizada usando las bases de datos Scopus, WoS y SciELO. Se analizaron 57 documentos que abordan temáticas como el impacto ambiental de la extracción, estrategias de reutilización, evaluaciones de criticidad y políticas de regulación de la actividad minera. Se concluye que los principales factores de la escasez de recursos están relacionados con la falta de normativa, la creciente demanda de nuevas tecnologías y discrepancia en los métodos de estimación de criticidad. Se advierte la necesidad de buscar alternativas de extracción y fomentar estrategias de recuperación de materiales.

Resumen Introducción: observaciones en líneas celulares sugieren que el uso de cinacalcet podría asociarse con un aumento de grasa corporal y del estado inflamatorio y una alteración del metabolismo lipídico. Sin embargo, al escalar el modelo a nivel clínico se desconoce la ocurrencia de estos efectos. Objetivos: analizar el efecto de la terapia con cinacalcet sobre parámetros antropométricos, inflamatorios y lipídicos en pacientes renales con hiperparatiroidismo secundario (HPT2). Métodos: estudio observacional con dos aproximaciones. El estudio retrospectivo incluyó 89 pacientes que iniciaron tratamiento de cinacalcet desde el año 2018 con un seguimiento máximo de 36 meses. Se analizaron variables de índice de masa corporal (IMC), circunferencia de cintura, pliegue tricipital, paratohormona (PTH) y perfil bioquímico. El estudio prospectivo incluyó 52 pacientes que iniciaron tratamiento con cinacalcet desde el año 2020 con un seguimiento de 12 meses. Se analizaron variables de IMC, PTH, perfil lipídico y proteína C reactiva (PCR). Resultados: en el estudio retrospectivo, el IMC fue de 27 kg/m2, con un 62 % de exceso de peso y un 65 % de los pacientes con riesgo cardiovascular elevado. Cinacalcet redujo la PTH un 12 % luego de seis meses (p < 0,01) y el calcio sérico disminuyó un 3,4 % al final del seguimiento (p = 0,04). En el estudio prospectivo, el IMC fue de 26,8 kg/m2, con un 60 % de exceso de peso. La PTH disminuyó un 8,4 % luego de seis meses. El colesterol total, el colesterol LDL y los triglicéridos disminuyeron en un 6,8 %, 12,5 % y 5,5 %, respectivamente, al finalizar el seguimiento. Conclusiones: el estado nutricional prevalente es el exceso de peso. En pacientes con HPT2 cinacalcet mejora el control de la PTH sin provocar cambios en parámetros antropométricos, lipídicos e inflamatorios.

Abstract Introduction: observations in cell lines suggest that the use of cinacalcet could be associated with increase in body fat, inflammatory state, and alteration in lipid metabolism. However, when scaling the model to the clinical level, the occurrence of these effects is unknown. Objectives: to analyze the effect of cinacalcet therapy on anthropometric, inflammatory and lipid parameters in renal patients with secondary hyperparathyroidism (SHPT). Methods: observational study with two approaches. The retrospective study included 89 patients who started cinacalcet treatment since 2018 with a maximum follow-up of 36 months. Body mass index (BMI) variables, waist circumference, tricipital skinfold, parathyroid hormone (PTH), and biochemical profile were analyzed. The prospective study included 52 patients who started cinacalcet treatment since 2020 with a 12-month follow-up. BMI, PTH, lipid profile, and PCR variables were analyzed. Results: in the retrospective study, BMI was 27 kg/m2, with 62 % overweight and 65 % of patients with high cardiovascular risk. Cinacalcet reduced PTH by 12 % after six months (p < 0.01) and serum calcium decreased by 3.4 % at the end of follow-up (p = 0.04). According to the prospective study, BMI was 26.8 kg/m2, with 60 % overweight. PTH decreased by 8.4 % after six months. Total cholesterol, LDL cholesterol, and triglycerides decreased by 6.8 %, 12.5 %, and 5.5 %, respectively, at the end of follow-up. Conclusions: the prevalent nutritional status is excess weight. In patients with SHPT, cinacalcet improves PTH control without causing changes in anthropometric, lipid, and inflammatory parameters.

ABSTRACT Objective. To evaluate the effectiveness of a standardized and simplified protocol based on the technical pillars of the HEARTS Initiative for the control of hypertensive patients in the Cardiovascular Health Program at the first level of care in Chile. Methods. Longitudinal observational study (historical cohort) in two family health centers at the first level of care in Santiago. The control of blood pressure in hypertensive adults using a standardized and simplified protocol was compared to the usual protocol based on national guidelines. Innovations in the standardized protocol included changes in how the health team is coordinated, initiation of pharmacological treatment immediately after confirmed diagnosis, standardized pharmacological treatment with a combination of at least two or three antihypertensive drugs taken daily in a single tablet. Follow-up was conducted after one year to assess the percentage of adherence to treatment and achievement of blood pressure control targets (< 140/90 mmHg). Results. A total of 1490 patients were evaluated: 562 who followed the standardized and simplified protocol, and 928 who were treated with the usual protocol (family health centers: 650; family health centers: 278). After one year, patients in the standardized and simplified protocol group had a higher proportion of adherence to blood pressure control targets (65% versus 37% and 41%, p<0.001) and higher adherence to treatment compared to those following the usual protocol (71% versus 18% and 23%, p<0.001). Conclusions. The results show that the standardized and simplified protocol is more effective than the usual protocol in controlling arterial hypertension in patients undergoing treatment at the first level of care in Chile. Its implementation at the national level could contribute to a decrease in major cardiovascular events.

RESUMO Objetivo. Avaliar a eficácia de um protocolo padronizado e simplificado, com base nos pilares técnicos da iniciativa HEARTS, para o controle de pacientes com hipertensão arterial do Programa de Saúde Cardiovascular na atenção primária à saúde do Chile. Métodos. Estudo observacional longitudinal (coorte histórica) em 2 centros de atenção primária de saúde da família em Santiago, que comparou o controle da pressão arterial em adultos com hipertensão, atingido com o protocolo padronizado e simplificado, versus o protocolo habitual, de acordo com as diretrizes nacionais. As inovações do protocolo padronizado incluíram mudanças na coordenação da equipe de saúde, início do tratamento farmacológico imediatamente após a confirmação do diagnóstico e tratamento farmacológico padronizado com associação de pelo menos 2 ou 3 anti-hipertensivos em um único comprimido, tomados uma vez ao dia. O acompanhamento foi realizado por 1 ano para avaliar o percentual de adesão ao tratamento e o cumprimento das metas de controle da pressão arterial (menor que 140/90 mmHg). Resultados. Foram avaliados 1.490 pacientes: 562 que utilizaram o protocolo padronizado e simplificado e 928 que foram tratados com o protocolo habitual (unidade de saúde da família 1: 650, unidade de saúde da família 2: 278). Em 1 ano de seguimento, os pacientes do grupo do protocolo padronizado e simplificado apresentaram maior proporção de cumprimento das metas de controle da pressão arterial (65% versus 37% e 41%, p<0,001) e maior percentual de adesão ao tratamento, em comparação com aqueles que utilizaram o protocolo habitual (71% versus 18% e 23%, p<0,001). Conclusões. Os resultados mostram que o protocolo padronizado e simplificado é mais eficaz que o protocolo habitual no controle da hipertensão arterial em pacientes que estão em tratamento na atenção primária do Chile. Sua implementação no nível nacional poderia contribuir para a redução de eventos cardiovasculares maiores.

RESUMEN Objetivo. Evaluar la eficacia de un protocolo estandarizado y simplificado basado en los pilares técnicos de la Iniciativa HEARTS para el control de pacientes hipertensos del Programa de Salud Cardiovascular en el primer nivel de atención de salud en Chile. Métodos. Estudio observacional longitudinal (cohorte histórica), en 2 centros de salud familiar del primer nivel de atención en Santiago, que comparó el control de presión arterial en adultos hipertensos logrado con el protocolo estandarizado y simplificado, frente al protocolo habitual, según las guías nacionales. Las innovaciones del protocolo estandarizado incluyeron cambios en la coordinación del equipo de salud, inicio de tratamiento farmacológico inmediatamente después de confirmación diagnóstica, tratamiento farmacológico estandarizado con combinación de al menos 2 o 3 fármacos antihipertensivos en un sólo comprimido, en una toma diaria. Se realizó seguimiento por 1 año para evaluar el porcentaje de adherencia al tratamiento y cumplimiento de metas de control de presión arterial (menor a 140/90 mmHg). Resultados. Se evaluaron 1 490 pacientes: 562 que utilizaron el protocolo estandarizado y simplificado y 928 tratados con el protocolo habitual (centros de salud familiar-1: 650, centros de salud familiar -2: 278). A 1 año de seguimiento, los pacientes del grupo del protocolo estandarizado y simplificado tuvieron mayor proporción de cumplimiento de metas de control de presión arterial (65% versus 37% y 41%, p<0,001) y mayor porcentaje de adherencia al tratamiento en comparación con aquellos con el protocolo habitual (71% versus 18% y 23%, p<0,001). Conclusiones. Los resultados muestran que el protocolo estandarizado y simplificado es más efectivo que el protocolo habitual en el control de hipertensión arterial en pacientes en tratamiento en el primer nivel de atención en Chile. Su implementación a nivel nacional podría contribuir a la disminución de eventos cardiovasculares mayores.

Abstract Background: protein restriction is the mainstay of dietary management of chronic kidney disease. Aim: to assess the usefulness of urine urea nitrogen measurement as a marker of protein restriction. Methods: healthy young participants were randomly divided in two groups. During 14 days, one group received a diet containing 30 kcal/kg body weight and 1 g protein/kg body weight and the other group received a diet with the same amount of calories and 0.6 g/kg of proteins. At baseline, seven days and 14 days, 24 h dietary recalls were answered by the participants. They collected 24 hour urine and provided spot urine samples at baseline and at the end of the intervention, to measure creatinine and urea nitrogen. Results: forty-one participants aged 29 ± 5 years completed the follow-up. According to 24h dietary recalls, the group receiving 0.6 g/kg protein reduced significantly the protein intake during the intervention from 0.88 ± 0.06 to 0.59 ± 0.05 g/kg/day. A significant reduction in 24 h urea nitrogen excretion was also observed in this group. In the group receiving 1 g/kg of protein, no significant changes in 24 h urea nitrogen excretion were observed. Among all participants, the odds ratio of observing a reduction in protein intake in the dietary survey was 5.75 (95% confidence intervals 1.29-25.55, p = 0.02), when a reduction in 24 h urea nitrogen excretion corrected by creatinine was observed. No changes were observed in urea nitrogen excretion in spot urine samples. Conclusions: repeated urea nitrogen excretion measured in 24 h urine samples can be a reliable indicator of dietary protein restriction.

Resumen Introducción: la restricción proteica es fundamental en el manejo de la enfermedad renal crónica. Objetivo: valuamos la utilidad de la medición de nitrógeno ureico urinario como marcador de restricción proteica. Métodos: participantes jóvenes sanos fueron divididos aleatoriamente en dos grupos. Un grupo recibió una dieta con 30 kcal/día/kg peso corporal y 1 g/proteína/día/kg peso corporal y el otro recibió una dieta con la misma cantidad de calorías pero con 0,6 g/kg peso corporal de proteína. Al inicio, a los siete y a los 14 días, los participantes respondieron una encuesta dietaria de recordatorio de 24 horas. Además, recolectaron orina de 24 horas y se les tomó una muestra aislada de orina al comienzo y a los 14 días de la intervención para medir creatinina y nitrógeno ureico. Resultados: cuarenta y un participantes de 29 ± 5 años completaron el estudio. El grupo que consumió 0,6 g/kg de proteínas redujo su ingesta proteica de 0,88 ± 0,06 a 0,59 ± 0,05 g/kg/día durante la intervención. En este grupo se observó una reducción significativa en la excreción urinaria de nitrógeno ureico en 24 horas. No se observó tal reducción en el grupo que consumió 1 g/kg de proteínas. La tasa de probabilidad de detectar una reducción en la ingesta proteica en las encuestas dietarias, cuando se observaba una disminución en la excreción urinaria de nitrógeno ureico/mg creatinina de 24 horas, fue de 5,75 (intervalos de confianza de 95% = 1,29-25,55, p = 0,02). No hubo cambios significativos en la excreción de nitrógeno ureico en las muestras aisladas de orina. Conclusión: las mediciones repetidas de nitrógeno ureico urinario en 24 horas son un marcador de restricción dietaria de proteínas.

Background: Type 2 Diabetes Mellitus is not always treated successfully, in part due to the difficulties perceived by the medical community about the use of insulin. Aim: To identify the constraints perceived by primary care physicians (PCPs) in the prescription and use of insulin. Material and Methods: Six PCPs were subjected to a semi-structured interview about self-perceived management difficulties, behaviors and beliefs on the use of insulin among diabetics. According to their responses a questionnaire about the subject was devised and PCPs were invited by e-mail to answer it. Results: There were 88 replies and 48% of respondents recognized to have management deficiencies in at least one aspect of insulin prescription. The most common deficiencies were determining the type of insulin and treatment of complications. The perceived difficulties were lack of training (58.0%), lack of medical hours (46.6%), lack of communication with specialists (46.6%), lack of reactive strips for capillary blood glucose determination (43.2%) and rotation of doctors (40.9%). The most common behaviors towards patients reluctant to use insulin were persuasion (83.0%), education and supervisión (63.6%) and signature ofan ad-hoc document (38.6%). Ninety percent considered that timely use of insulin is more beneficial  than its prescription as a last resort and 94.3% did not consider that insulin should be prescribed by a specialist. Conclusions: A significant percentage of physicians do not trust their own knowledge about insulin prescription. These professionals should receive training in not only technical aspects of prescribing insulin, but also in the psychological and persuasión strategies. There is willingness among PCPs to prescribe insulin.

Background: The study RENAAL (Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan) demonstrated that Losartan was more effective lo reduce the progression of kidney disease in diabetic patients with proteinuria and a reduction in glomerular filtration rate. Aim: To perform a cost benefit analysis of Losartan use from provider and payer points of view. Material and methods: Published data of the RENAAL study was analyzed. The costs of the use or not use of Losartan in patients with diabetic nephropathy were compared in terms of total costs of the disease including medications, hospital admissions for myocardial infarction, cerebrovascular accidents and congestive cardiac failure and the costs of chronic hemodialysis. Results: The reduction in antihypertensive medication use, hospital admissions, and the delay in dialysis requirement from a mean of 65 to 79 months induced by Losartan use, results in net savings of $7,576,135 per patient, at 3.5 years of intervention. The figure does not change using different sensitivity scenarios. Conclusions: The eventual use of Losartan in type 2 diabetic patients results in important savings.