1,462 research outputs found
Extracardiac 18F-florbetapir imaging in patients with systemic amyloidosis: more than hearts and minds
PURPOSE: 18F-Florbetapir has been reported to show cardiac uptake in patients with systemic light-chain amyloidosis (AL). This study systematically assessed uptake of 18F-florbetapir in patients with proven systemic amyloidosis at sites outside the heart. METHODS: Seventeen patients with proven cardiac amyloidosis underwent 18F-florbetapir PET/CT imaging, 15 with AL and 2 with transthyretin amyloidosis (ATTR). Three patients had repeat scans. All patients had protocolized assessment at the UK National Amyloidosis Centre including imaging with 123I-serum amyloid P component (SAP). 18F-Florbetapir images were assessed for areas of increased tracer accumulation and time-uptake curves in terms of standardized uptake values (SUVmean) were produced. RESULTS: All 17 patients showed 18F-florbetapir uptake at one or more extracardiac sites. Uptake was seen in the spleen in 6 patients (35%; 6 of 9, 67%, with splenic involvement on 123I-SAP scintigraphy), in the fat in 11 (65%), in the tongue in 8 (47%), in the parotids in 8 (47%), in the masticatory muscles in 7 (41%), in the lungs in 3 (18%), and in the kidney in 2 (12%) on the late half-body images. The 18F-florbetapir spleen retention index (SRI) was calculated. SRI >0.045 had 100% sensitivity/sensitivity (in relation to 123I-SAP splenic uptake, the current standard) in detecting splenic amyloid on dynamic imaging and a sensitivity of 66.7% and a specificity of 100% on the late half-body images. Intense lung uptake was seen in three patients, one of whom had lung interstitial infiltration suggestive of amyloid deposition on previous high-resolution CT. Repeat imaging showed a stable appearance in all three patients suggesting no early impact of treatment response. CONCLUSION: 18F-Florbetapir PET/CT is a promising tool for the detection of extracardiac sites of amyloid deposition. The combination of uptake in the heart and uptake in the spleen on 18F-florbetapir PET/CT, a hallmark of AL, suggests that this tracer holds promise as a screening tool for AL
Systemic amyloidosis in England: an epidemiological study.
Epidemiological studies of systemic amyloidosis are scarce and the burden of disease in England has not previously been estimated. In 1999, the National Health Service commissioned the National Amyloidosis Centre (NAC) to provide a national clinical service for all patients with amyloidosis. Data for all individuals referred to the NAC is held on a comprehensive central database, and these were compared with English death certificate data for amyloidosis from 2000 to 2008, obtained from the Office of National Statistics. Amyloidosis was stated on death certificates of 2543 individuals, representing 0·58/1000 recorded deaths. During the same period, 1143 amyloidosis patients followed at the NAC died, 903 (79%) of whom had amyloidosis recorded on their death certificates. The estimated minimum incidence of systemic amyloidosis in the English population in 2008, based on new referrals to the NAC, was 0·4/100 000 population. The incidence peaked at age 60-79 years. Systemic AL amyloidosis was the most common type with an estimated minimum incidence of 0·3/100 000 population. Although there are various limitations to this study, the available data suggest the incidence of systemic amyloidosis in England exceeds 0·8/100 000 of the population
The epidemiology of injuries across the weight-training sports
Background: Weight-training sports, including weightlifting, powerlifting, bodybuilding, strongman, Highland Games, and CrossFit, are weight-training sports that have separate divisions for males and females of a variety of ages, competitive standards, and bodyweight classes. These sports may be considered dangerous because of the heavy loads commonly used in training and competition. Objectives: Our objective was to systematically review the injury epidemiology of these weight-training sports, and, where possible, gain some insight into whether this may be affected by age, sex, competitive standard, and bodyweight class. Methods: We performed an electronic search using PubMed, SPORTDiscus, CINAHL, and Embase for injury epidemiology studies involving competitive athletes in these weight-training sports. Eligible studies included peer-reviewed journal articles only, with no limit placed on date or language of publication. We assessed the risk of bias in all studies using an adaption of the musculoskeletal injury review method. Results: Only five of the 20 eligible studies had a risk of bias score ≥75 %, meaning the risk of bias in these five studies was considered low. While 14 of the studies had sample sizes >100 participants, only four studies utilized a prospective design. Bodybuilding had the lowest injury rates (0.12–0.7 injuries per lifter per year; 0.24–1 injury per 1000 h), with strongman (4.5–6.1 injuries per 1000 h) and Highland Games (7.5 injuries per 1000 h) reporting the highest rates. The shoulder, lower back, knee, elbow, and wrist/hand were generally the most commonly injured anatomical locations; strains, tendinitis, and sprains were the most common injury type. Very few significant differences in any of the injury outcomes were observed as a function of age, sex, competitive standard, or bodyweight class. Conclusion: While the majority of the research we reviewed utilized retrospective designs, the weight-training sports appear to have relatively low rates of injury compared with common team sports. Future weight-training sport injury epidemiology research needs to be improved, particularly in terms of the use of prospective designs, diagnosis of injury, and changes in risk exposure
Diagnosis, pathogenesis and outcome in leucocyte chemotactic factor 2 (ALECT2) amyloidosis
Introduction:
Renal biopsy series from North America suggest that leucocyte chemotactic factor 2 (ALECT2) amyloid is the third most common type of renal amyloid. We report the first case series from a European Centre of prevalence, clinical presentation and diagnostic findings in ALECT2 amyloidosis and report long-term patient and renal outcomes for the first time.
Methods:
We studied the clinical features, diagnostic investigations and the outcome of all patients with ALECT2 amyloidosis followed systematically at the UK National Amyloidosis Centre (NAC) between 1994 and 2015.
Results:
Twenty-four patients, all non-Caucasian, were diagnosed with ALECT2 amyloidosis representing 1.3% of all patients referred to the NAC with biopsy-proved renal amyloid. Diagnosis was made at median age of 62 years, usually from renal histology; immunohistochemical staining was definitive for ALECT2 fibril type. Median estimated glomerular filtration rate (GFR) at diagnosis was 33 mL/min/1.73 m2 and median proteinuria was 0.5 g/24 h. Hepatic amyloid was evident on serum amyloid P component (SAP) scintigraphy in 11/24 cases but was not associated with significant derangement of liver function. No patient had evidence of cardiac amyloidosis or amyloid neuropathy. Median follow-up was 4.8 (range 0.5–15.2) years, during which four patients died and four progressed to end-stage renal disease. The mean rate of GFR loss was 4.2 (range 0.5–9.6) mL/min/year and median estimated renal survival from diagnosis was 8.2 years. Serial SAP scans revealed little or no change in total body amyloid burden.
Conclusions:
ALECT2 amyloidosis is a relatively benign type of renal amyloid, associated with a slow GFR decline, which is reliably diagnosed on renal histology. Neither the molecular basis nor the factors underlying the apparent restriction of ALECT2 amyloidosis to non-Caucasian populations have been determined
Diagnostic sensitivity of abdominal fat aspiration in cardiac amyloidosis
Aims:
Congo red staining of an endomyocardial biopsy is the diagnostic gold-standard in suspected cardiac amyloidosis (CA), but the procedure is associated with the risk, albeit small, of serious complications, and delay in diagnosis due to the requirement for technical expertise. In contrast, abdominal fat pad fine needle aspiration (FPFNA) is a simple, safe and well-established procedure in systemic amyloidosis, but its diagnostic sensitivity in patients with suspected CA remains unclear.
Methods and results:
We assessed the diagnostic sensitivity of FPFNA in 600 consecutive patients diagnosed with CA [216 AL amyloidosis, 113 hereditary transthyretin (ATTRm), and 271 wild-type transthyretin (ATTRwt) amyloidosis] at our Centre. Amyloid was detected on Congo red staining of FPFNAs in 181/216 (84%) patients with cardiac AL amyloidosis, including 100, 97, and 78% of those with a large, moderate, and small whole-body amyloid burden, respectively, as assessed by serum amyloid P (SAP) component scintigraphy (P < 0.001); the deposits were successfully typed as AL by immunohistochemistry in 102/216 (47%) cases. Amyloid was detected in FPFNAs of 51/113 (45%) patients with ATTRm CA, and only 42/271 (15%) cases with ATTRwt CA.
Conclusions:
FPFNA has reasonable diagnostic sensitivity in cardiac AL amyloidosis, particularly in patients with a large whole-body amyloid burden. Although the diagnostic sensitivity of FPFNA is substantially lower in transthyretin CA, particularly ATTRwt, it may nevertheless sometimes obviate the need for endomyocardial biopsy
Comparison of sequencing-based methods to profile DNA methylation and identification of monoallelic epigenetic modifications.
Analysis of DNA methylation patterns relies increasingly on sequencing-based profiling methods. The four most frequently used sequencing-based technologies are the bisulfite-based methods MethylC-seq and reduced representation bisulfite sequencing (RRBS), and the enrichment-based techniques methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylated DNA binding domain sequencing (MBD-seq). We applied all four methods to biological replicates of human embryonic stem cells to assess their genome-wide CpG coverage, resolution, cost, concordance and the influence of CpG density and genomic context. The methylation levels assessed by the two bisulfite methods were concordant (their difference did not exceed a given threshold) for 82% for CpGs and 99% of the non-CpG cytosines. Using binary methylation calls, the two enrichment methods were 99% concordant and regions assessed by all four methods were 97% concordant. We combined MeDIP-seq with methylation-sensitive restriction enzyme (MRE-seq) sequencing for comprehensive methylome coverage at lower cost. This, along with RNA-seq and ChIP-seq of the ES cells enabled us to detect regions with allele-specific epigenetic states, identifying most known imprinted regions and new loci with monoallelic epigenetic marks and monoallelic expression
Defining the expression hierarchy of latent T-cell epitopes in Epstein-Barr virus infection with TCR-like antibodies
Epstein-Barr virus (EBV) is a gamma herpesvirus that causes a life-long latent infection in human hosts. The latent gene products LMP1, LMP2A and EBNA1 are expressed by EBV-associated tumors and peptide epitopes derived from these can be targeted by CD8 Cytotoxic T-Lymphocyte (CTL) lines. Whilst CTL-based methodologies can be utilized to infer the presence of specific latent epitopes, they do not allow a direct visualization or quantitation of these epitopes. Here, we describe the characterization of three TCR-like monoclonal antibodies (mAbs) targeting the latent epitopes LMP1[subscript 125–133], LMP2A[subscript 426–434] or EBNA1[subscript 562–570] in association with HLA-A0201. These are employed to map the expression hierarchy of endogenously generated EBV epitopes. The dominance of EBNA1[subscript 562–570] in association with HLA-A0201 was consistently observed in cell lines and EBV-associated tumor biopsies. These data highlight the discordance between MHC-epitope density and frequencies of associated CTL with implications for cell-based immunotherapies and/or vaccines for EBV-associated disease
Current warming will reduce yields unless maize breeding and seed systems adapt immediately
The development of crop varieties that are better suited to new climatic conditions is vital for future food production1, 2. Increases in mean temperature accelerate crop development, resulting in shorter crop durations and reduced time to accumulate biomass and yield3, 4. The process of breeding, delivery and adoption (BDA) of new maize varieties can take up to 30 years. Here, we assess for the first time the implications of warming during the BDA process by using five bias-corrected global climate models and four representative concentration pathways with realistic scenarios of maize BDA times in Africa. The results show that the projected difference in temperature between the start and end of the maize BDA cycle results in shorter crop durations that are outside current variability. Both adaptation and mitigation can reduce duration loss. In particular, climate projections have the potential to provide target elevated temperatures for breeding. Whilst options for reducing BDA time are highly context dependent, common threads include improved recording and sharing of data across regions for the whole BDA cycle, streamlining of regulation, and capacity building. Finally, we show that the results have implications for maize across the tropics, where similar shortening of duration is projected
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos2Δϕ modulation for all ΣETPb ranges and particle pT
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