Natural and laboratory-guided evolution has created a rich diversity of fluorescent protein (FP)-based sensors for chloride (Cl
−
). To date, such sensors have been limited to the
Aequorea victoria
...green fluorescent protein (avGFP) family, and fusions with other FPs have unlocked ratiometric imaging applications. Recently, we identified the yellow fluorescent protein from jellyfish
Phialidium
sp. (phiYFP) as a fluorescent turn-on, self-ratiometric Cl
−
sensor. To elucidate its working mechanism as a rare example of a single FP with this capability, we tracked the excited-state dynamics of phiYFP using femtosecond transient absorption (fs-TA) spectroscopy and target analysis. The photoexcited neutral chromophore undergoes bifurcated pathways with the twisting-motion-induced nonradiative decay and barrierless excited-state proton transfer. The latter pathway yields a weakly fluorescent anionic intermediate
, followed by the formation of a red-shifted fluorescent state
that enables the ratiometric response on the tens of picoseconds timescale. The redshift results from the optimized π-π stacking between chromophore Y66 and nearby Y203, an ultrafast molecular event. The anion binding leads to an increase of the chromophore p
K
a
and ESPT population, and the hindrance of
conversion. The interplay between these two effects determines the turn-on fluorescence response to halides such as Cl
−
but turn-off response to other anions such as nitrate as governed by different binding affinities. These deep mechanistic insights lay the foundation for guiding the targeted engineering of phiYFP and its derivatives for ratiometric imaging of cellular chloride with high selectivity.
We discovered an interplay between proton transfer and conformational reorganization that powers a standalone fluorescent-protein-based excitation-ratiometric biosensor for chloride imaging.
Background
The Erector Spinae Plane (ESP) block is a recent development in the field of regional anaesthesia and has been increasingly explored for abdominal surgeries to reduce opioid use and ...improve pain control. Colorectal cancer is the commonest cancer in multi-ethnic Singapore and requires surgery for curative treatment. ESP is a promising alternative in colorectal surgeries, but few studies have evaluated its efficacy in such surgeries. Therefore, this study aims to evaluate the use of ESP blocks in laparoscopic colorectal surgeries to establish its safety and efficacy in this field.
Methods
A prospective two-armed interventional cohort study comparing T8–T10 ESP blocks with conventional multimodal intravenous analgesia for laparoscopic colectomies was conducted in a single institution in Singapore. The decision for doing an ESP block versus conventional multimodal intravenous analgesia was made by a consensus between the attending surgeon and anesthesiologist. Outcomes measured were total intra-operative opioid consumption, post-operative pain control and patient outcome. Post-operative pain control was measured by pain score, analgesia use, and amount of opioids consumed. Patient outcome was determined by presence of ileus.
Results
A total of 146 patients were included, of which 30 patients received an ESP block. Overall, the ESP group had a significantly lower median opioid usage both intra-operatively and post-operatively (
p
= 0.031). Fewer patients required patient-controlled analgesia and rescue analgesia post-operatively for pain control (
p
< 0.001) amongst the ESP group. Pain scores were similar and post-operative ileus was absent in both groups. Multivariate analysis found that the ESP block had an independent effect on reducing intra-opioid consumption (
p
= 0.014). Multivariate analysis of post-operative opioid use and pain scores did not yield statistically significant results.
Conclusions
The ESP block was an effective alternative regional anaesthesia for colorectal surgery that reduced intra-operative and post-operative opioid use while attaining satisfactory pain control.
Graphical abstract
To identify factors related to the frequency of physical activity (PA) promotion by health professionals working in cardiac and/or pulmonary rehabilitation.
A cross-sectional online survey of health ...professionals working in cardiac and/or pulmonary rehabilitation in Australia was conducted between July and November 2022.
A total of 71 health professionals from four disciplines (physiotherapy, nursing, exercise physiology, occupational therapy) completed the survey. The majority agreed that PA promotion was part of their role. Despite this, only half of the participants encouraged ≥ 10 patients per month to be more physically active. In logistic regression modelling, health professionals that measured patients’ PA levels (odds ratio 8.04, 95% confidence level 1.45–44.19) and prioritised PA promotion regardless of other patient problems (odds ratio 3.3, 95% confidence level 0.74–14.82) were much more likely to frequently promote PA to patients.
Measurement of patients’ PA levels within cardiac and pulmonary rehabilitation and making PA promotion a priority may impact the implementation of PA promotion within these programs.
Physical activity measurement as a key performance indicator in cardiac and pulmonary rehabilitation is indicated. This may be an important strategy to increase physical activity promotion by cardiac and pulmonary rehabilitation health professionals.
•Cardiac & pulmonary rehab clinicians agree physical activity (PA) promotion is key.•If patient’s PA levels were measured clinicians were much more likely to promote PA.•Clinicians that prioritised PA promotion were more likely to promote PA.•PA measurement as a key performance indicator within rehab is recommended.
SARS-CoV-2 enters the body through inhalation or self-inoculation to mucosal surfaces. The kinetics of the ocular and nasal mucosal-specific-immunoglobulin A(IgA) responses remain under-studied.
...Conjunctival fluid (CF,
= 140) and nasal epithelial lining fluid (NELF,
= 424) obtained by paper strips and plasma (
= 153) were collected longitudinally from SARS-CoV-2 paediatric (
= 34) and adult (
= 47) patients. The SARS-CoV-2 spike protein 1(S1)-specific mucosal antibody levels in COVID-19 patients, from hospital admission to six months post-diagnosis, were assessed.
The mucosal antibody was IgA-predominant. In the NELF of asymptomatic paediatric patients, S1-specific IgA was induced as early as the first four days post-diagnosis. Their plasma S1-specific IgG levels were higher than in symptomatic patients in the second week after diagnosis. The IgA and IgG levels correlated positively with the surrogate neutralization readout. The detectable NELF "receptor-blocking" S1-specific IgA in the first week after diagnosis correlated with a rapid decline in viral load.
Early and intense nasal S1-specific IgA levels link to a rapid decrease in viral load. Our results provide insights into the role of mucosal immunity in SARS-CoV-2 exposure and protection. There may be a role of NELF IgA in the screening and diagnosis of SARS-CoV-2 infection.
Purpose
Drug-coated balloon angioplasty (DCBA) has been studied as a potentially superior option compared to conventional percutaneous transluminal angioplasty (PTA) in treating below-the-knee (BTK) ...arteries in chronic limb-threatening ischemia (CLTI). The aim of this study is to examine the cost-effectiveness of DCBA versus PTA in BTK arteries based on a randomized controlled trial.
Material and Methods
A prospective economic study was embedded in a randomized controlled trial of 138 patients with CLTI. Resource use and health outcomes were assessed at baseline, and at 3, 6 and 12 months post-intervention. Costs were calculated from a societal perspective and health outcomes measured using quality-adjusted life years with probabilistic sensitivity analysis performed to account for subject heterogeneity.
Results
Compared with participants randomized to receive PTA, participants randomized to DCBA gained an average baseline-adjusted quality-adjusted life years (QALYs) of .012 while average total costs were USD$1854 higher; this translates to an incremental cost-effectiveness ratio (ICER) of US$154,500 additional cost per QALY gained. However, the estimate of ICER had substantial variance with only 48% of bootstrap ICERs meeting a benchmark threshold of US$57,705 (the average gross domestic product (GDP) per capita of Singapore).
Conclusion
The use of DCBA in BTK arteries in CLTI patients was not cost-effective compared with PTA.
Level of Evidence
2, Randomized trial.
The hepatitis B X protein (HBx) plays a role in the epigenetic regulation of hepatitis B virus (HBV) replication. This study investigated the effects of HBx mutations on HBV transcription and the ...recruitment of HBx, histone acetyl-transferase P300 and histone deacetylase 1 (HDAC1) to circularized HBV DNA (which resembles covalently closed circular DNA cccDNA). Compared with wild type, majority of mutants had lower levels of intracellular HBV RNA (44-77% reduction) and secretory HBsAg (25-81% reduction), and 12 mutants had a reduction in intracellular encapsidated HBV DNA (33-64% reduction). Eight mutants with >70% reduction in HBV RNA and/or HBsAg were selected for chromatin immunoprecipitation analysis. Four HBx mutants with mutations in amino acid residues 55-60 and 121-126 had a lower degree of HBx-cccDNA association than wild type HBx (mean % input: 0.02-0.64% vs. 3.08% in wild type). A reduced association between cccDNA and P300 (mean % input: 0.69-1.81% vs. 3.48% in wild type) and an augmented association with HDAC1 (mean % input: 4.01-14.0% vs. 1.53% in wild type) were detected. HBx amino acid residues 55-60 and 121-126 may play an important role in HBV transcription regulation, via their impeded interaction with cccDNA and altered recruitment of histone modifying enzymes to cccDNA.
PurposeThe purpose of this paper is to identify the continuance usage of livestreaming commerce. The proposed antecedents of livestreaming commerce continuance usage are social presence, perceived ...crowdedness, need for arousal, susceptibility to informational influence, and perceived value, whilst trust in broadcasters is treated as the moderating factor.Design/methodology/approachA survey was conducted using a questionnaire designed specifically for this purpose, which was completed by 388 Malaysian consumers aged 26–40 years who have prior experience with livestreaming commerce. The authors tested the framework using the partial least squares structural equation modelling (PLS-SEM) technique and complementary by performing artificial neural network (ANN) analysis.FindingsThe results indicate several significant relationships, whereby social presence, perceived crowdedness, susceptibility to informational influence, and trust in broadcasters significantly influence perceived value, whereas perceived value significantly influences continuance intention. In addition, trust in broadcasters moderates the relationship between perceived value and continuance intention.Originality/valueThe current study adds significantly to the body of knowledge about livestreaming by examining the direct determinants of perceived value and thus delineating how perceived value influences continuance intention. The findings yielded also illustrate the role of trust in broadcaster as the moderator of the link between perceived value and continuance intention.
We detected African swine fever virus (ASFV) from a wild boar in Singapore. In <72 hours, we confirmed and reported ASFV p72 genotype II, CD2v serogroup 8, and IGR-II variant by using a combination ...of real-time PCR and whole-genome sequencing. Continued biosurveillance will be needed to monitor ASFV in Singapore.
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