Impact of photobleaching of fluorescent proteins on FRET measurements under two-photon excitation.

Förster resonance energy transfer (FRET) is a widely used technique for nanoscale molecular distance measurements, which makes FRET ideal for studying protein interactions and quaternary structure of protein complexes. In this work, we were interested in how photobleaching of donor and acceptor molecules affects the FRET results under various excitation conditions. We conducted a systematic study, under two-photon excitation, of the effects of the excitation power and the choice of excitation wavelengths upon the measured FRET efficiencies of multiplex protein constructs, consisting of one donor (D) and two acceptors (A) or one acceptor and a non-fluorescent tag (N), using both the kinetic theory of FRET and numerical simulations under given excitation conditions.

Mechanistic insights from the atomic-level quaternary structure of short-lived GPCR oligomers in live cells.

The functional significance of the interactions between proteins in living cells to form short-lived quaternary structures cannot be overemphasized. Yet, quaternary structure information is not captured by current methods, neither can those methods determine structure within living cells. The dynamic versatility, abundance, and functional diversity of G protein-coupled receptors (GPCRs) pose myriad challenges to existing technologies but also present these proteins as the ideal testbed for new technologies to investigate the complex inter-regulation of receptor-ligand, receptor-receptor, and receptor-downstream effector interfaces in living cells.

Implementation of FRET Spectrometry Using Temporally Resolved Fluorescence: A Feasibility Study.

Förster resonance energy transfer (FRET) spectrometry is a method for determining the quaternary structure of protein oligomers from distributions of FRET efficiencies that are drawn from pixels of fluorescence images of cells expressing the proteins of interest. FRET spectrometry protocols currently rely on obtaining spectrally resolved fluorescence data from intensity-based experiments. Another imaging method, fluorescence lifetime imaging microscopy (FLIM), is a widely used alternative to compute FRET efficiencies for each pixel in an image from the reduction of the fluorescence lifetime of the donors caused by FRET.

The Epidemiology of Injuries in Adults in Nepal: Findings from a Hospital-Based Injury Surveillance Study.

This study aimed to develop and evaluate a model of hospital-based injury surveillance and describe the epidemiology of injuries in adults. One-year prospective surveillance was conducted in two hospitals in Hetauda, Nepal. Data were collected electronically for patients presenting to emergency departments (EDs) with injuries between April 2019 and March 2020.

Development and Evaluation of a Community Surveillance Method for Estimating Deaths Due to Injuries in Rural Nepal.

Almost 10% of global deaths are secondary to injuries, yet in the absence of routine injury surveillance and with few studies of injury mortality, the number and cause of injury deaths in many countries are not well understood. This study aimed to develop and evaluate the feasibility of a method to identify injury deaths in rural Nepal. Working with local government authorities, health post staff and female community health volunteers (FCHVs), we developed a two-stage community fatal injury surveillance approach.

Comparative photophysical properties of some widely used fluorescent proteins under two-photon excitation conditions.

Understanding the photophysical properties of fluorescent proteins (FPs), such as emission and absorption spectra, molecular brightness, photostability, and photo-switching, is critical to the development of criteria for their selection as tags for fluorescent-based biological applications. While two-photon excitation imaging techniques have steadily gained popularity - due to comparatively deeper penetration depth, reduced out-of-focus photobleaching, and wide separation between emission spectra and two-photon excitation spectra -, most studies reporting on the photophysical properties of FPs tend to remain focused on single-photon excitation. Here, we report our investigation of the photophysical properties of several commonly used fluorescent proteins using two-photon microscopy with spectral resolution in both excitation and emission.

Perceptions of injury risk in the home and workplace in Nepal: a qualitative study.

Objective: Injuries are a global health problem. To develop context-specific injury prevention interventions, one needs to understand population perceptions of home and workplace injuries. This study explored a range of views and perceptions about injuries in a variety of settings and identified barriers and facilitators to injury prevention.

Home-related and work-related injuries in Makwanpur district, Nepal: a household survey.

Objective: To describe the epidemiology of home-related and work-related injuries, their mechanisms, inequalities and costs associated with these injuries.

Methods: A household survey was undertaken in three palikas of Makwanpur district between April and June 2019. Data were collected electronically on non-fatal injuries that occurred in the previous 3 months and fatal injuries that occurred in the previous 5 years.

Long-term impact of community-based participatory women's groups on child and maternal mortality and child disability: follow-up of a cluster randomised trial in rural Nepal.

Background: Community-based women's groups practising participatory learning and action (PLA) can reduce maternal and neonatal mortality in low-income countries. However, it is not clear whether these reductions are associated with subsequent increased or decreased rates of childhood death and disability. We assessed the impact on child deaths and disability beyond the perinatal period among participants in the earliest trial in Nepal 2001-2003.

Prenatal and perinatal risk factors for disability in a rural Nepali birth cohort.

Background: Improving newborn health remains a global health priority. Little however is known about the neurodevelopmental consequences for survivors of complications in pregnancy, labour and the neonatal period in in low-income countries outside of small selective and typically urban facility studies. We ask which antenatal, birth and neonatal factors are associated with disability in childhood in a large community birth cohort from rural Nepal.

Disabled women׳s maternal and newborn health care in rural Nepal: a qualitative study.

Objective: there is little evidence about disabled women׳s access to maternal and newborn health services in low-income countries and few studies consult disabled women themselves to understand their experience of care and care seeking. Our study explores disabled women׳s experiences of maternal and newborn care in rural Nepal.

Design: we used a qualitative methodology, using semi-structured interviews.