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Entre marzo y octubre de 2002 se compararon los ensamblajes de hormigas que forrajean en el suelo en un sistema no manejado (reserva natural El Ciprés) y en algunas fincas vecinas. En dos transectos de 100 m se instalaron estaciones de muestreo cada 10 m con trampa de caída (pitfall) y cebo de atún epígeo durante 880 h y 92 días respectivamente. En 1471 eventos de captura se determinaron 68 especies distribuidas en 26 géneros y 8 subfamilias. En el sistema silvopastoril- guayaba y en monocultivo de granadilla (Passiflora ligularis) dominaron las especies de hormigas mientras que la distribución fue más equitativa en los usos del terreno con estructura vegetal más compleja (bosque, café, sucesión temprana y banco de forrajes). El sistema silvopastoril-guayaba fue el más rico en especies (31) seguido por café (30) y por el bosque y la sucesión temprana (29). El flujo de especies fue alto en bosque, café y sucesión temprana, indicando que la calidad de la matriz es factor importante para el mantenimiento de la biodiversidad.

La caficultra nacional es una actividad económica de primer orden que trasciende el ámbito sectorial; en la actualidad atravieza una difícil coyuntura por la situación de los mercados mjundiales, que a partir de la terminación del Pacto Cafetero de Cuotas, presentan una fuerte baja en precios y una alta acumulación de existencias en manos de los tostadores. En este artículo se hace un esfuerzo de carácter exploratorio a nivel de la empresa, para buscar soluciones que contribuyan junto a otras de carócter macroeconómico a mantener en un nivel adeucado el ingreso cafetero; al mejoramiento de las eficiencias internas productivas y a la técnica de la Administración Rural, se les conceden especial relevancia, para los efectos anotados.The coffee production is the main activity of the Colombian agricultural sector. However, coffee production, at the present time, is going through the worst crisis in its history due to the coffee prices at the New York and London eschanges. We discuss some farm management principies and other practices with in the farm as very important factors - besides macroeconomic policies to take into account to overcome the problems faced by the coffee growers.

Migration of endothelial and many other cells requires spatiotemporal regulation of protrusive and contractile cytoskeletal rearrangements that drive local cell shape changes. Unexpectedly, the small GTPase Rho, a crucial regulator of cell movement, has been reported to be active in both local cell protrusions and retractions, raising the question of how Rho activity can coordinate cell migration. Here, we show that Rho activity is absent in local protrusions and active during retractions. During retractions, Rho rapidly activated ezrin-radixin-moesin proteins (ERMs) to increase actin-membrane attachment, and, with a delay, nonmuscle myosin 2 (NM2). Rho activity was excitable, with NM2 acting as a slow negative feedback regulator. Strikingly, inhibition of SLK/LOK kinases, through which Rho activates ERMs, caused elongated cell morphologies, impaired Rho-induced cell contractions, and reverted Rho-induced blebbing. Together, our study demonstrates that Rho activity drives retractions by sequentially enhancing ERM-mediated actin-membrane attachment for force transmission and NM2-dependent contractility.

Flow or collective movement is a frequently observed phenomenon for many cellular components including the cytoskeletal proteins actin and myosin. To study protein flow in living cells, we and others have previously used spatiotemporal image correlation spectroscopy (STICS) analysis on fluorescence microscopy image time series. Yet, in cells, multiple protein flows often occur simultaneously on different scales resulting in superimposed fluorescence intensity fluctuations that are challenging to separate using STICS. Here, we exploited the characteristic that distinct protein flows often occur at different spatial scales present in the image series to disentangle superimposed protein flow dynamics. We employed a newly developed and an established spatial filtering algorithm to alternatively accentuate or attenuate local image intensity heterogeneity across different spatial scales. Subsequently, we analysed the spatially filtered time series with STICS, allowing the quantification of two distinct superimposed flows within the image time series. As a proof of principle of our analysis approach, we used simulated fluorescence intensity fluctuations as well as time series of nonmuscle myosin II in endothelial cells and actin-based podosomes in dendritic cells and revealed simultaneously occurring contiguous and noncontiguous flow dynamics in each of these systems. Altogether, this work extends the application of STICS for the quantification of multiple protein flow dynamics in complex biological systems including the actomyosin cytoskeleton., (© 2024 The Author(s). Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.)

Goal: To describe the dynamics of syndromic surveillance of ILI cases in seasonal and COVID-19 pandemic scenarios., Methodology: A descriptive study of the epidemiological behavior of ILI in the seasonal and COVID-19 pandemic scenarios. Of a sample of 16,231 cases of ILI from 2013 to 2021, the features of cases from 68 weeks before and during the pandemic were selected and compared; weekly endemic channels were built; data fluctuations on the trend of ILI cases were analyzed; and estimated weekly correlations between weekly P25 age, cases confirmed by rapid tests, and mortality from COVID-19. To analyze clinical-epidemiological and mortality data, Student's t test, Mann-Whitney U, Chi2, Spearman's Ro, polynomial, and multinomial regression with a 95% confidence interval were used., Results: During the COVID-19 pandemic, those most affected with ILI were: adults and the elderly; higher median age; autochthonous cases predominated; a lower proportion of other syndromes; delays in seeking care; and a higher rate of pneumonia attack than in the seasonal period (p< 0.01). Rapid tests (serological and antigenic) confirmed 52.7% as COVID-19. Two ILI pandemic waves were seasonally consistent with confirmed COVID-19 cases and district mortality with robust correlation (p<0.01) before and during the pandemic, especially the ILI weekly P25 age, which has a more robust correlation with mortality than ILI and rapid tests (p<0.01) whose endemic channels describe and could predict the evolution of the pandemic (p<0.01)., Conclusions: The pandemic changed the clinical and epidemiological behavior of ILI, and the weekly P25 of age is a more robust indicator to monitor the COVID-19 pandemic than a rapid test and could predict its evolution., Competing Interests: This does not alter our adherence to the PLOS ONE policy on sharing data and materials., (Copyright: © 2024 Ocaña Gutiérrez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The human respiratory syncytial virus (hRSV) is the leading etiologic agent causing respiratory infections in infants, children, older adults, and patients with comorbidities. Sixty-seven years have passed since the discovery of hRSV, and only a few successful mitigation or treatment tools have been developed against this virus. One of these is immunotherapy with monoclonal antibodies against structural proteins of the virus, such as Palivizumab, the first prophylactic approach approved by the Food and Drug Administration (FDA) of the USA. In this article, we discuss different strategies for the prevention and treatment of hRSV infection, focusing on the molecular mechanisms against each target that underly the rational design of antibodies against hRSV. At the same time, we describe the latest results regarding currently approved therapies against hRSV and the challenges associated with developing new candidates., Competing Interests: Declaration of competing interest The authors declare the following possible conflict of interest: Dr. Alexis Kalergis has a patent ‘Monoclonal Antibody specific against the antigen N of the Human Respiratory Syncytial Virus (VRSH), useful for the treatment of infection, its detection, and diagnosis: PCT/CL 2018/050,079, date of presentation September 2018. The authors report no other conflicts of interest in this work., (Copyright © 2023 Elsevier B.V. All rights reserved.)