Correlative cryo-imaging of the cellular universe with soft X-rays and laser light used to track F-actin structures in mammalian cells.

Imaging of actin filaments is crucial due to the integral role that they play in many cellular functions such as intracellular transport, membrane remodelling and cell motility. Visualizing actin filaments has so far relied on fluorescence microscopy and electron microscopy/tomography. The former lacks the capacity to capture the overall local ultrastructure, while the latter requires rigorous sample preparation that can lead to potential artefacts, and only delivers relatively small volumes of imaging data at the thinnest areas of a cell. In this work, a correlative approach utilizing in situ super-resolution fluorescence imaging and cryo X-ray tomography was used to image bundles of actin filaments deep inside cells under near-native conditions. In this case, fluorescence 3D imaging localized the actin bundles within the intracellular space, while X-ray tomograms of the same areas provided detailed views of the local ultrastructure. Using this new approach, actin trails connecting vesicles in the perinuclear area and hotspots of actin presence within and around multivesicular bodies were observed. The characteristic prevalence of filamentous actin in cytoplasmic extensions was also documented.

Data-deposition protocols for correlative soft X-ray tomography and super-resolution structured illumination microscopy applications.

This protocol illustrates the steps necessary to deposit correlated 3D cryo-imaging data from cryo-structured illumination microscopy and cryo-soft X-ray tomography with the BioStudies and EMPIAR deposition databases of the European Bioinformatics Institute. There is currently a real need for a robust method of data deposition to ensure unhindered access to and independent validation of correlative light and X-ray microscopy data to allow use in further comparative studies, educational activities, and data mining. For complete details on the use and execution of this protocol, please refer to Kounatidis et al. (2020).

Quantifying Seasonal Variation in Insecticide-Treated Net Use among Those with Access.

Seasonal variation in the proportion of the population using an insecticide-treated net (ITN) is well documented and is widely believed to be dependent on mosquito abundance and heat, driven by rainfall and temperature. However, seasonal variation in ITN use has not been quantified controlling for ITN access. Demographic and Health Survey and Malaria Indicator Survey datasets, their georeferenced data, and public rainfall and climate layers were pooled for 21 countries. Nine rainfall typologies were developed from rainfall patterns in Köppen climate zones. For each typology, the odds of ITN use among individuals with access to an ITN within their households ("ITN use given access") were estimated for each month of the year, controlling for region, wealth quintile, residence, year, temperature, and malaria parasitemia level. Seasonality of ITN use given access was observed over all nine rainfall typologies and was most pronounced in arid climates and less pronounced where rainfall was relatively constant throughout the year. Peak ITN use occurred 1-3 months after peak rainfall and corresponded with peak malaria incidence and average malaria transmission season. The observed lags between peak rainfall and peak ITN use given access suggest that net use is triggered by mosquito density. In equatorial areas, ITN use is likely to be high year-round, given the presence of mosquitoes and an associated year-round perceived malaria risk. These results can be used to inform behavior change interventions to improve ITN use in specific times of the year and to inform geospatial models of the impact of ITNs on transmission.

Creating a future laboratory workforce: a California group's success.

In early 2001, a small group of hospital lab administrators, educators, and hospital council and health occupations leaders in the South San Francisco Bay Area, seeing no end to the area's laboratory workforce shortage, developed an ambitious plan to increase the number of clinical laboratory scientists (CLSs). Here is how they convinced administrators from 15 area hospitals to fund it.