Crowding and the epidemic intensity of COVID-19 transmission

The COVID-19 pandemic is straining public health systems worldwide and major non-pharmaceutical interventions have been implemented to slow its spread1-4. During the initial phase of the outbreak the spread was primarily determined by human mobility5,6. Yet empirical evidence on the effect of key geographic factors on local epidemic spread is lacking7. We analyse highly-resolved spatial variables for cities in China together with case count data in order to investigate the role of climate, urbanization, and variation in interventions across China. Here we show that the epidemic intensity of COVID-19 is strongly shaped by crowding, such that epidemics in dense cities are more spread out through time, and denser cities have larger total incidence. Observed differences in epidemic intensity are well captured by a metapopulation model of COVID-19 that explicitly accounts for spatial hierarchies. Densely-populated cities worldwide may experience more prolonged epidemics. Whilst stringent interventions can shorten the time length of these local epidemics, although these may be difficult to implement in many affected settings.

Alteration of inflammatory adipokines after four months of smoking abstinence in multidisciplinary intervention program.

BACKGROUND: many endocrine-metabolic changes are involved in smoking. OBJECTIVES: to evaluate serum concentrations of inflammatory adipokines in smokers at baseline and after four months of treatment for smoking cessation. METHODS: the serum concentrations of inflammatory cytokines were evaluated in smokers and abstinent. Nutritional assessment was based on measurements of body weight, height, and waist circumference (WC), to calculate body mass index (BMI), body adiposity index (BAI) and waist-to-height ratio (WHtR). Biochemical parameters were analyzed: total cholesterol, LDL-c, HDL-c, triglycerides, glucose, cortisol and insulin. The serum levels of leptin, adiponectin and ghrelin were determined by enzyme-linked immunosorbent assay (ELISA). The leptin/adiponectin ratio (L/A) was calculated. RESULTS: a total of 29 subjects were included in this study (22 women and seven men). The mean age of participants was 50.7 ± 10.47 years. The medium values of WHtR and BAI were above of the proposed cutoff point, indicating abdominal obesity. The biochemical parameters did not present statistically significant differences when comparing the initial and final values. At the end of treatment, the abstinent had higher levels of adiponectin when compared to those who remained smoker (p = 0.024). There was an increase in leptin levels and L/A, and a reduction in adiponectin levels after the treatment in abstinent and smokers (p < 0.05). CONCLUSION: this study has demonstrated that smoking cessation improves adiponectin levels when compared with smokers. Leptin and L/A levels increased throughout the treatment in both groups. The increased values of leptin and L/A in abstinent participants may indicate risk of metabolic events associated with smoking history that should be investigated.

Alteration of inflammatory adipokines after four months of smoking abstinence in multidisciplinary intervention program / Cambio en las adipocinas inflamatorias tras cuatro meses de abstinencia de fumar en un programa de intervención multimodal

Background: many endocrine-metabolic changes are involved in smoking. Objectives: to evaluate serum concentrations of inflammatory adipokines in smokers at baseline and after four months of treatment for smoking cessation. Methods: the serum concentrations of inflammatory cytokines were evaluated in smokers and abstinent. Nutritional assessment was based on measurements of body weight, height, and waist circumference (WC), to calculate body mass index (BMI), body adiposity index (BAI) and waist-to-height ratio (WHtR). Biochemical parameters were analyzed: total cholesterol, LDL-c, HDL-c, triglycerides, glucose, cortisol and insulin. The serum levels of leptin, adiponectin and ghrelin were determined by enzyme-linked immunosorbent assay (ELISA). The leptin/adiponectin ratio (L/A) was calculated. Results: a total of 29 subjects were included in this study (22 women and seven men). The mean age of participants was 50.7 ± 10.47 years. The medium values of WHtR and BAI were above of the proposed cutoff point, indicating abdominal obesity. The biochemical parameters did not present statistically significant differences when comparing the initial and final values. At the end of treatment, the abstinent had higher levels of adiponectin when compared to those who remained smoker (p = 0.024). There was an increase in leptin levels and L/A, and a reduction in adiponectin levels after the treatment in abstinent and smokers (p < 0.05). Conclusion: this study has demonstrated that smoking cessation improves adiponectin levels when compared with smokers. Leptin and L/A levels increased throughout the treatment in both groups. The increased values of leptin and L/A in abstinent participants may indicate risk of metabolic events associated with smoking history that should be investigated

Introducción: en el tabaquismo están involucrados un gran número de cambios endocrino-metabólicos. Objetivos: evaluar las concentraciones séricas de adipocinas inflamatorias en fumadores al inicio y después de cuatro meses de tratamiento para dejar de fumar. Métodos: se evaluaron las concentraciones séricas de citocinas inflamatorias en fumadores y no fumadores. La evaluación nutricional se basó en las mediciones del peso corporal y la altura, para calcular el índice de masa corporal (IMC), la circunferencia de la cintura (CC), el índice de adiposidad corporal (IAC) y la relación cintura/estatura (RCE). Se analizaron los parámetros bioquímicos: colesterol total, LDL-c, HDL-c, triglicéridos, glucosa, cortisol e insulina. Los niveles séricos de leptina, adiponectina y grelina se determinaron mediante ensayo de inmunoabsorción enzimática (ELISA). Se calculó la relación leptina/adiponectina (L/A). Resultados: se incluyeron un total de 29 personas (22 mujeres y siete hombres). La edad media de los participantes fue de 50,7 ± 10,47 años. Los valores medios de CC e IAC se mostraron por encima del punto de corte propuesto, indicando obesidad abdominal. Los parámetros bioquímicos no presentaron diferencias estadísticamente significativas al comparar los valores iniciales y finales. Al final del tratamiento, los abstinentes tenían niveles más altos de adiponectina cuando se comparaban con los de aquellos que seguían fumando (p = 0,024). Hubo un aumento en los niveles de leptina y L/A y reducción de los niveles de adiponectina después del tratamiento en abstinentes y fumadores (p < 0,05). Conclusiones: este estudio ha demostrado que el abandono del hábito de fumar mejora los niveles de adiponectina en comparación con los fumadores. Los niveles de leptina y L/A aumentaron a lo largo del tratamiento en ambos grupos. Los valores aumentados de leptina y L/A en abstinentes pueden indicar riesgo de eventos metabólicos asociados al historial de tabaquismo que deben ser investigados

Th2 responses in OVA-sensitized BALB/c mice are down-modulated by Mycobacterium bovis BCG treatment.

OBJECTIVE: This study aimed to determine whether Mycobacterium bovis Bacillus Calmette-Guérin (BCG) treatment can reverse an established allergic airway inflammation in a BALB/c mouse model of ovalbumin (OVA)-induced airway inflammation. METHODS: OVA sensitized BALB/c mice were challenged with aerosolized OVA on days 28 to 30, 34, 41 and 63. Mice were intranasal treated with BCG on days 35 and 42. Twenty-four hours after the last challenge, blood samples were collected to detect anti-OVA immunoglobulin isotypes, and bronchoalveolar lavage (BAL) was harvested for cell count. Additionally, lungs were collected for histological analysis, detection of the eosinophil peroxidase (EPO) activity and measurement of cytokines and CCL11. The expression of CTLA-4, Foxp3 and IL-10 was also determined in lung tissue by flow cytometry. RESULTS: BCG treatment was able to inhibit an established allergic Th2-response, by decreasing the allergen-induced eosinophilic inflammation, EPO activity, levels of CCL11 and IL-4, serum levels of IgE and IgG1. Mycobacteria treatment increased lung levels of IFN-γ, IL-10 and TGF-ß, and expressions of Foxp3 and CTLA-4 in CD4(+)T cells. Additionally, an increased production of IL-10 by CD8(+) T cells was observed, even though no detectable changes in CD4(+)IL-10(+) was noticed. CONCLUSION: BCG treatment inhibits features of allergic airway inflammation and the results suggest that the mechanism underlying the down-regulatory effects of BCG on OVA-induced airway inflammation appear to be associated with the induction of both Th1 and T regulatory immune responses.

Avaliação rebrota da copa das árvores de pau-rosa (Aniba rosaeodora Ducke) em sistema de podas sucessivas / Evaluation of resprouting of rosewood tree (Aniba rosaeodora Ducke) crowns in sucessive prunings

O estudo foi conduzido em um plantio de pau-rosa com 36 anos, localizado na Reserva Florestal Adolpho Ducke, Manaus-AM, Brasil, latitude 03°00' 00 "e 03°08'00" S e longitude 59°52'40 "e 59°58'00" W. Foi determinada a biomassa da rebrota da copa das árvores de pau-rosa (Aniba rosaeodora Ducke, Lauraceae), podadas duas vezes (em 2000 e 2002) e das árvores podadas três vezes (em 1987, 2000 e 20002). Os resultados não indicaram diferenças significativas entre o DAP, altura total, número de brotos/fuste, comprimento e diâmetro dos brotos e peso verde da copa das árvores podadas duas ou três vezes. Os coeficientes de regressão e de correlação de Pearson indicaram que a biomassa da copa das árvores podadas pela terceira vez está fortemente correlacionada com a radiação PAR direta, PAR difusa, PAR total e o índice de área foliar. O elevado número de brotos/fuste revelou boa capacidade da rebrota da copa após sucessivas podas, fato que possibilita o manejo da biomassa das árvores através de podas.

This study was carried out in a rosewood plantation (36 years-old) located in the Adolpho Ducke Forest Reserve, Manaus, Amazonas, Brazil, latitude 03°00' 00 " to 03°08'00" S and longitude 59°52'40 " to 59°58'00" W. The biomass of sprouts was determined from twice pruned (2000 and 2002) rosewood ( Aniba rosaeodora Ducke, Lauraceae) tree crowns, and from those harvested three times (1987, 2000 and 2002). The results show that there are no significant differences in biomass productions between trees harvested two or tree times for the following parameters: DBH, total height, number of sprouts per bole, sprout length and diameter, and fresh canopy fresh weight. The regression and Pearson correlation coefficients showed that crown biomass from the third pruning was strongly correlated with direct PAR, diffuse PAR and total PAR and LAI (leaf area index). The high number of sprouts per bole reveals the crown's resprouting capacity after successive pruning. This shows that the species can be managed for biomass production through successive pruning.