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21.
Background Excess adiposity at diagnosis and weight gain during chemotherapy is associated with tumour recurrence and chemotherapy toxicity. We assessed the efficacy of intermittent energy restriction (IER) vs continuous energy restriction (CER) for weight control and toxicity reduction during chemotherapy.Methods One hundred and seventy-two women were randomised to follow IER or CER throughout adjuvant/neoadjuvant chemotherapy. Primary endpoints were weight and body fat change. Secondary endpoints included chemotherapy toxicity, cardiovascular risk markers, and correlative markers of metabolism, inflammation and oxidative stress.Results Primary analyses showed non-significant reductions in weight (−1.1 (−2.4 to +0.2) kg, p = 0.11) and body fat (−1.0 (−2.1 to +0.1) kg, p = 0.086) in IER compared with CER. Predefined secondary analyses adjusted for body water showed significantly greater reductions in weight (−1.4 (−2.5 to −0.2) kg, p = 0.024) and body fat (−1.1 (−2.1 to −0.2) kg, p = 0.046) in IER compared with CER. Incidence of grade 3/4 toxicities were comparable overall (IER 31.0 vs CER 36.5%, p = 0.45) with a trend to fewer grade 3/4 toxicities with IER (18%) vs CER (31%) during cycles 4–6 of primarily taxane therapy (p = 0.063).Conclusions IER is feasible during chemotherapy. The potential efficacy for weight control and reducing toxicity needs to be tested in future larger trials.Clinical trial registration ISRCTN04156504.Subject terms: Randomized controlled trials, Breast cancer, Nutrition, Weight management, Breast cancer  相似文献   
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Whole-genome sequencing of viral isolates is critical for informing transmission patterns and for the ongoing evolution of pathogens, especially during a pandemic. However, when genomes have low variability in the early stages of a pandemic, the impact of technical and/or sequencing errors increases. We quantitatively assessed inter-laboratory differences in consensus genome assemblies of 72 matched SARS-CoV-2-positive specimens sequenced at different laboratories in Sydney, Australia. Raw sequence data were assembled using two different bioinformatics pipelines in parallel, and resulting consensus genomes were compared to detect laboratory-specific differences. Matched genome sequences were predominantly concordant, with a median pairwise identity of 99.997%. Identified differences were predominantly driven by ambiguous site content. Ignoring these produced differences in only 2.3% (5/216) of pairwise comparisons, each differing by a single nucleotide. Matched samples were assigned the same Pango lineage in 98.2% (212/216) of pairwise comparisons, and were mostly assigned to the same phylogenetic clade. However, epidemiological inference based only on single nucleotide variant distances may lead to significant differences in the number of defined clusters if variant allele frequency thresholds for consensus genome generation differ between laboratories. These results underscore the need for a unified, best-practices approach to bioinformatics between laboratories working on a common outbreak problem.  相似文献   
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ObjectiveIn this review, we summarize ongoing clinical trials involving liquid biopsies (LB) for colorectal cancer (CRC), outlining the current landscape and the future implementation of this technology. We also describe the current use of LB in CRC treatment at our institution, the Mayo Clinic Enterprise.BackgroundThe use of LB in CRC treatment merits close attention. Their role is being evaluated in the screening, non-intervention, intervention, and surveillance settings through many active trials. This, coupled with the technique’s rapid integration into clinical practice, creates constant evolution of care.MethodsReview of ClinicalTrials.gov was performed identifying relevant and active trials involving LB for CRC. “Colorectal cancer” plus other terms including “liquid biopsies” and “ctDNA” were used as search terms, identifying 35 active trials.ConclusionsLB use for the CRC is actively being investigated and requires close attention. Based on current evidence, Mayo Clinic Enterprise currently uses LB in the non-interventional, interventional and surveillance setting, but not for screening. Results of these trials may further establish the use of LB in the management of CRC.  相似文献   
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Short‐chain enoyl‐CoA hydratase (SCEH or ECHS1) deficiency is a rare inborn error of metabolism caused by biallelic mutations in the gene ECHS1 (OMIM 602292). Clinical presentation includes infantile‐onset severe developmental delay, regression, seizures, elevated lactate, and brain MRI abnormalities consistent with Leigh syndrome (LS). Characteristic abnormal biochemical findings are secondary to dysfunction of valine metabolism. We describe four patients from two consanguineous families (one Pakistani and one Irish Traveler), who presented in infancy with LS. Urine organic acid analysis by GC/MS showed increased levels of erythro‐2,3‐dihydroxy‐2‐methylbutyrate and 3‐methylglutaconate (3‐MGC). Increased urine excretion of methacrylyl‐CoA and acryloyl‐CoA related metabolites analyzed by LC‐MS/MS, were suggestive of SCEH deficiency; this was confirmed in patient fibroblasts. Both families were shown to harbor homozygous pathogenic variants in the ECHS1 gene; a c.476A > G (p.Gln159Arg) ECHS1variant in the Pakistani family and a c.538A > G, p.(Thr180Ala) ECHS1 variant in the Irish Traveler family. The c.538A > G, p.(Thr180Ala) ECHS1 variant was postulated to represent a Canadian founder mutation, but we present SNP genotyping data to support Irish ancestry of this variant with a haplotype common to the previously reported Canadian patients and our Irish Traveler family. The presence of detectable erythro‐2,3‐dihydroxy‐2‐methylbutyrate is a nonspecific marker on urine organic acid analysis but this finding, together with increased excretion of 3‐MGC, elevated plasma lactate, and normal acylcarnitine profile in patients with a Leigh‐like presentation should prompt consideration of a diagnosis of SCEH deficiency and genetic analysis of ECHS1. ECHS1 deficiency can be added to the list of conditions with 3‐MGA.  相似文献   
28.

Background

Increasing pressures on emergency departments (ED) are straining services and creating inefficiencies in service delivery worldwide. A potentially avoidable pressure is inappropriate attendances (IA); typically low urgency, self-referred patients better managed by other services. This study examines demographics and temporal trends associated with IA to help inform measures to address them.

Methods

Using a national ED dataset, a cross-sectional examination of ED attendances in England from April 2011 to March 2012 (n?=?15,056,095) was conducted. IA were defined as patients who were self-referred; were not attending a follow-up; received no investigation and either no treatment or ‘guidance/advice only’; and were discharged with either no follow-up or follow-up with primary care. Small, nationally representative areas were used to assign each attendance to a residential measure of deprivation. Multivariate analysis was used to predict relationships between IA, demographics (age, gender, deprivation) and temporal factors (day, month, hour, bank holiday, Christmas period).

Results

Overall, 11.7% of attendances were categorized as inappropriate. IA peaked in early childhood (adjusted odds ratio (AOR)?=?1.53 for both one and two year olds), and was elevated throughout late-teens and young adulthood, with odds reducing steadily from age 27 (reference category, age 40). Both IA and appropriate attendances (AA) were most frequent in the most deprived populations. However, relative to AA, those living in the least deprived areas had the highest odds of IA (AOR?=?0.89 in most deprived quintile). Odds of IA were also higher for males (AOR?=?0.95 in females). Both AA and IA were highest on Mondays, whilst weekends, bank holidays and the period between 8 am and 4 pm saw more IA relative to AA.

Conclusions

Prevention of IA would be best targeted at parents of young children and at older youths/young adults, and during weekends and bank holidays. Service provision focusing on access to primary care and EDs serving the most deprived communities would have the most benefit. Improvements in coverage and data quality of the national ED dataset, and the addition of an appropriateness field, would make this dataset an effective monitoring tool to evaluate interventions addressing this issue.
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29.
We have previously shown that unlike endogenous ? genes, unrearranged ? transgenes undergo V?-J? recombination in T as well as B cells of transgenic mice. To determine whether the difference in recombination specificity of the transgenic and endogenous ? genes is associated with differences in DNA structure, the methylation status of the endogenous genes and three unrearranged ? transgenes was compared. The J?-C? locus of the transgenes was found to be hypomethylated in all tissues of the transgenic mice. In contrast, methylation of the endogenous ? genes was tissue and developmentally regulated. Hypomethylation of the endogenous J?-C? region occurs only in cells of the B lineage undergoing, or having completed ? gene recombination. Transfection of fibroblasts from transgenic and control mice with the recombination activating genes, Rag1 and Rag2, led to a high level of rearrangement of the hypomethylated transgenic, but not the endogenous ? genes. These results suggest that hypomethylation defines an accessible state of the ? locus and that methylation/demethylation could be involved in the control of ? gene rearrangement during lymphocyte differentiation.  相似文献   
30.
Aim: To investigate static and dynamic visuospatial working memory (VSWM) processes in first‐episode psychosis (FEP) patients and explore the validity of such measures as specific trait markers of schizophrenia. Methods: Twenty FEP patients and 20 age‐, sex‐, laterality‐ and education‐matched controls carried out a dynamic and static VSWM paradigm. At 2‐year follow up 13 patients met Diagnostic and Statistical Manual (of Mental Health Disorders) – Fourth Edition (DSM‐IV) criteria for schizophrenia, 1 for bipolar disorder, 1 for brief psychotic episode and 5 for schizotypal personality disorder. Results: Compared with controls, the 20 FEP patients showed severe impairment in the dynamic VSWM condition but much less impairment in the static condition. No specific bias in stimulus selection was detected in the two tasks. Two‐year follow‐up evaluations suggested poorer baseline scores on the dynamic task clearly differentiated the 13 FEP patients who developed schizophrenia from the seven who did not. Conclusions: Results suggest deficits in VSWM in FEP patients. Specific exploratory analyses further suggest that deficit in monitoring‐manipulation VSWM processes, especially involved in our dynamic VSWM task, can be a reliable marker of schizophrenia.  相似文献   
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