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31.
BackgroundIn 2020, the SARS-CoV-2 (COVID-19) pandemic and lockdown control measures threatened to disrupt routine childhood immunisation programmes with early reports suggesting uptake would fall. In response, public health bodies in Scotland and England collected national data for childhood immunisations on a weekly or monthly basis to allow for rapid analysis of trends. The aim of this study was to use these data to assess the impact of different phases of the pandemic on infant and preschool immunisation uptake rates.Methods and findingsWe conducted an observational study using routinely collected data for the year prior to the pandemic (2019) and immediately before (22 January to March 2020), during (23 March to 26 July), and after (27 July to 4 October) the first UK “lockdown”. Data were obtained for Scotland from the Public Health Scotland “COVID19 wider impacts on the health care system” dashboard and for England from ImmForm.Five vaccinations delivered at different ages were evaluated; 3 doses of “6-in-1” diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b, and hepatitis B vaccine (DTaP/IPV/Hib/HepB) and 2 doses of measles, mumps, and rubella (MMR) vaccine. This represented 439,754 invitations to be vaccinated in Scotland and 4.1 million for England. Uptake during the 2020 periods was compared to the previous year (2019) using binary logistic regression analysis. For Scotland, uptake within 4 weeks of a child becoming eligible by age was analysed along with geographical region and indices of deprivation. For Scotland and England, we assessed whether immunisations were up-to-date at approximately 6 months (all doses 6-in-1) and 16 to 18 months (first MMR) of age.We found that uptake within 4 weeks of eligibility in Scotland for all the 5 vaccines was higher during lockdown than in 2019. Differences ranged from 1.3% for first dose 6-in-1 vaccine (95.3 versus 94%, odds ratio [OR] compared to 2019 1.28, 95% confidence intervals [CIs] 1.18 to 1.39) to 14.3% for second MMR dose (66.1 versus 51.8%, OR compared to 2019 1.8, 95% CI 1.74 to 1.87). Significant increases in uptake were seen across all deprivation levels.In England, fewer children due to receive their immunisations during the lockdown period were up to date at 6 months (6-in-1) or 18 months (first dose MMR). The fall in percentage uptake ranged from 0.5% for first 6-in-1 (95.8 versus 96.3%, OR compared to 2019 0.89, 95% CI 0.86– to 0.91) to 2.1% for third 6-in-1 (86.6 versus 88.7%, OR compared to 2019 0.82, 95% CI 0.81 to 0.83).The use of routinely collected data used in this study was a limiting factor as detailed information on potential confounding factors were not available and we were unable to eliminate the possibility of seasonal trends in immunisation uptake.ConclusionsIn this study, we observed that the national lockdown in Scotland was associated with an increase in timely childhood immunisation uptake; however, in England, uptake fell slightly. Reasons for the improved uptake in Scotland may include active measures taken to promote immunisation at local and national levels during this period and should be explored further. Promoting immunisation uptake and addressing potential vaccine hesitancy is particularly important given the ongoing pandemic and COVID-19 vaccination campaigns.

Fiona McQuaid and colleagues assess the uptake of infant and pre-school immunisations in Scotland and England during the COVID-19 pandemic.  相似文献   
32.
We tested the hypothesis that myocardial ischemia-reperfusion (I/R)-induced apoptosis is attenuated in transgenic mice overexpressing cardiac A(1) adenosine receptors. Isolated hearts from transgenic (TG, n = 19) and wild-type (WT, n = 22) mice underwent 30 min of ischemia and 2 h of reperfusion, with evaluation of apoptosis, caspase 3 activity, function, and necrosis. I/R-induced apoptosis was attenuated in TG hearts. TG hearts had less I/R-induced apoptotic nuclei (0.88 +/- 0.10% vs. 4.22 +/- 0.24% terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells in WT, P < 0.05), less DNA fragmentation (3.30 +/- 0.38-fold vs. 4.90 +/- 0.39-fold over control in WT, P < 0.05), and less I/R-induced caspase 3 activity (145 +/- 25% over nonischemic control vs. 234 +/- 31% in WT, P < 0.05). TG hearts also had improved recovery of function and less necrosis than WT hearts. In TG hearts pretreated with LY-294002 (3 microM) to evaluate the role of phosphosinositol-3-kinase in acute signaling, there was no change in the functional protection or apoptotic response to I/R. These data suggest that cardioprotection with transgenic overexpression of A(1) adenosine receptors involves attenuation of I/R-induced apoptosis that does not involve acute signaling through phosphoinositol-3-kinase.  相似文献   
33.
APP processing is regulated by cytoplasmic phosphorylation   总被引:14,自引:0,他引:14       下载免费PDF全文
Amyloid-beta peptide (Abeta) aggregate in senile plaque is a key characteristic of Alzheimer's disease (AD). Here, we show that phosphorylation of amyloid precursor protein (APP) on threonine 668 (P-APP) may play a role in APP metabolism. In AD brains, P-APP accumulates in large vesicular structures in afflicted hippocampal pyramidal neurons that costain with antibodies against endosome markers and the beta-secretase, BACE1. Western blot analysis reveals increased levels of T668-phosphorylated APP COOH-terminal fragments in hippocampal lysates from many AD but not control subjects. Importantly, P-APP cofractionates with endosome markers and BACE1 in an iodixanol gradient and displays extensive colocalization with BACE1 in rat primary cortical neurons. Furthermore, APP COOH-terminal fragments generated by BACE1 are preferentially phosphorylated on T668 verses those produced by alpha-secretase. The production of Abeta is significantly reduced when phosphorylation of T668 is either abolished by mutation or inhibited by T668 kinase inhibitors. Together, these results suggest that T668 phosphorylation may facilitate the BACE1 cleavage of APP to increase Abeta generation.  相似文献   
34.
The folding of alpha-helical membrane proteins has previously been described using the two stage model, in which the membrane insertion of independently stable alpha-helices is followed by their mutual interactions within the membrane to give higher order folding and oligomerization. Given recent advances in our understanding of membrane protein structure it has become apparent that in some cases the model may not fully represent the folding process. Here we present a three stage model which gives considerations to ligand binding, folding of extramembranous loops, insertion of peripheral domains and the formation of quaternary structure.  相似文献   
35.
Previous studies have shown that high-level (300-fold normal) cardiac overexpression of A1-adenosine receptors (A1-ARs) in transgenic (TG) mice protects isolated hearts against ischemia-reperfusion injury. However, this high level of overexpression is associated with bradycardia and increased incidence of arrhythmia during ischemia in intact mice, which interfered with studies to determine whether this line of TG mice might also be protected against myocardial infarction (MI) in vivo. For these studies, we therefore selected a line of TG mice that overexpresses the A1-AR at more moderate levels (30-fold normal), which affords cardioprotection in the isolated heart while minimizing bradycardia and arrhythmia during ischemia in intact mice. Wild-type (WT; n = 10) and moderate-level A1-AR TG (n = 10) mice underwent 45 min of left anterior descending coronary artery occlusion, followed by 24-h reperfusion. Infarct size and region at risk were determined by triphenyltetrazolium chloride and phthalo blue staining, respectively. Infarct size (% region at risk) in WT mice was 52 +/- 3%, whereas overexpression of A1-ARs in the TG mice markedly reduced infarct size to 31 +/- 3% (P < 0.05). Furthermore, contractile function (left ventricular ejection fraction) as determined by cardiac magnetic resonance imaging 24 h after MI was better preserved in TG vs. WT mice. Cardiac overexpression of A1-ARs reduces infarct size by 40% and preserves cardiac function in intact mice after MI.  相似文献   
36.
An assay based on a solvent-sensitive fluorogenic dye molecule, badan, is used to test the binding affinity of a library of tetrapeptide molecules for the BIR3 (baculovirus IAP repeat) domain of XIAP (X-linked inhibitor of apoptosis protein). The fluorophore is attached to a tetrapeptide, Ala-Val-Pro-Cys-NH(2), through a thiol linkage and, upon binding to XIAP, undergoes a solvatochromic shift in fluorescence emission. When a molecule (e.g., a natural protein known to bind to XIAP or a tetrapeptide mimic) displaces the dye, the emission shifts back to the spectrum observed in water. As emission intensity is related to the binding of the tetrapeptide, the intensity can be used to determine the equilibrium constant, K, for the displacement of the dye by the tetrapeptide. The results permit residue-specific analysis of the interaction. Furthermore, we show that hydrophobic effects in the fourth position are general and can effectively increase overall affinity.  相似文献   
37.
Exudates were collected from stumps of pre-anthesis inflorescences of oil palm and analysed for cytokinin and gibberellin content using combined HPLC-ELISA techniques. Three antisera, for zeatin-type, dihydrozeatin-type and isopentenyladenine-type cytokinins, were used in ELISAs to identify members of these three groups of cytokinins. Ribotides, 9-glucosides, free bases and ribosides were detected for each of the groups with zeatin riboside the most abundant cytokinin identified in the exudate. Isopentenyladenine-type and dihydrozeatin-type cytokinins were also identified but at lower levels. In addition, two monoclonal antibodies were used in the development of novel ELISAs for members of the 13-hydroxylated and non-13-hydroxylated families of gibberellins. The new ELISAs allow the determination of gibberellins in smaller amounts of tissue than are required for GC-MS. The most abundant gibberellins identified in exudates were GA19 and GA44, as well as other members of the early 13-hydroxylation pathway. Gibberellins were confirmed by GC-MS. The presence of these types of growth regulators in exudate supplying immature inflorescences suggest they have a role in growth and development of these structures.  相似文献   
38.
Quantification of strength with hand-held dynamometers is commonplace. Hand-held dynamometers offer ease of use; however, previous investigations have shown much variability between repeated measures using the same dynamometer. Even less is known regarding the degree of variability between various dynamometers. Therefore, the intent of this investigation was to compare measures of hip abduction strength recorded with 3 different but commonly used hand-held dynamometers, specifically the Microfet 2 Load Cell, Jamar Hand-Held, and Dial Push-Pull Gauge. Maximal isometric hip abduction strength was recorded in 10 women (27.6 +/- 6.2 years) over 3 consecutive days using a different device each day. A significant difference in recorded force was noted between the devices (p < 0.001) as the Microfet showed significantly less force than the others. This was supported by intraclass correlation coefficients (ICCs) ranging from 0.277 to 0.688. These data suggest that consideration must be given to using the same dynamometer when quantifying strength over repeated sessions.  相似文献   
39.
40.
The 26S proteasome complex plays a major role in the non-lysosomal degradation of intracellular proteins. Purified 26S proteasomes give a pattern of more than 40 spots on 2D-PAGE gels. The positions of subunits have been identified by mass spectrometry of tryptic peptides and by immunoblotting with subunit-specific antipeptide antibodies. Two-dimensional polyacrylamide gel electrophoresis of proteasomes immunoprecipitated from [32P]phosphate-labelled human embryo lung L-132 cells revealed the presence of at least three major phosphorylated polypeptides among the regulatory subunits as well as the C8 and C9 components of the core 20S proteasome. Comparison with the positions of the regulatory polypeptides revealed a minor phosphorylated form to be S7 (MSS1). Antibodies against S4, S6 (TBP7) and S12 (MOV34) all cross-reacted at the position of major phosphorylated polypeptides suggesting that several of the ATPase subunits may be phosphorylated. The phosphorylation of S4 was confirmed by double immunoprecipitation experiments in which 26S proteasomes were immunoprecipitated as above and dissociated and then S4 was immunoprecipitated with subunit-specific antibodies. Antibodies against the non-ATPase subunit S10, which has been suggested by others to be phosphorylated, did not coincide with the position of a phosphorylated polypeptide. Some differences were observed in the 2D-PAGE pattern of proteasomes immunoprecipitated from cultured cells compared to purified rat liver 26S proteasomes suggesting possible differences in subunit compositions of 26S proteasomes.  相似文献   
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