SummaryBackgroundModerate cooling after birth asphyxia is associated with substantial reductions in death and disability, but additional therapies might provide further benefit. We assessed whether the addition of xenon gas, a promising novel therapy, after the initiation of hypothermia for birth asphyxia would result in further improvement.MethodsTotal Body hypothermia plus Xenon (TOBY-Xe) was a proof-of-concept, randomised, open-label, parallel-group trial done at four intensive-care neonatal units in the UK. Eligible infants were 36–43 weeks of gestational age, had signs of moderate to severe encephalopathy and moderately or severely abnormal background activity for at least 30 min or seizures as shown by amplitude-integrated EEG (aEEG), and had one of the following: Apgar score of 5 or less 10 min after birth, continued need for resuscitation 10 min after birth, or acidosis within 1 h of birth. Participants were allocated in a 1:1 ratio by use of a secure web-based computer-generated randomisation sequence within 12 h of birth to cooling to a rectal temperature of 33·5°C for 72 h (standard treatment) or to cooling in combination with 30% inhaled xenon for 24 h started immediately after randomisation. The primary outcomes were reduction in lactate to N-acetyl aspartate ratio in the thalamus and in preserved fractional anisotropy in the posterior limb of the internal capsule, measured with magnetic resonance spectroscopy and MRI, respectively, within 15 days of birth. The investigator assessing these outcomes was masked to allocation. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00934700, and with ISRCTN, as ISRCTN08886155.FindingsThe study was done from Jan 31, 2012, to Sept 30, 2014. We enrolled 92 infants, 46 of whom were randomly assigned to cooling only and 46 to xenon plus cooling. 37 infants in the cooling only group and 41 in the cooling plus xenon group underwent magnetic resonance assessments and were included in the analysis of the primary outcomes. We noted no significant differences in lactate to N-acetyl aspartate ratio in the thalamus (geometric mean ratio 1·09, 95% CI 0·90 to 1·32) or fractional anisotropy (mean difference −0·01, 95% CI −0·03 to 0·02) in the posterior limb of the internal capsule between the two groups. Nine infants died in the cooling group and 11 in the xenon group. Two adverse events were reported in the xenon group: subcutaneous fat necrosis and transient desaturation during the MRI. No serious adverse events were recorded.InterpretationAdministration of xenon within the delayed timeframe used in this trial is feasible and apparently safe, but is unlikely to enhance the neuroprotective effect of cooling after birth asphyxia.FundingUK Medical Research Council.
Background: Iron repletion augments exercise capacity in chronic heart failure (HF), but there is a lack of mechanistic data explaining how iron could augment exercise performance despite minimal changes in hemoglobin (Hb). Besides Hb, iron is an obligate component of mitochondrial enzymes that generate cellular energy in the form of adenosine triphosphate and phosphocreatine (PCr). Dynamic phosphorus magnetic resonance spectroscopy is a noninvasive tool that quantifies in vivo muscle energetics by measuring the kinetics of PCr recovery after exertion. We tested the hypothesis that intravenous iron repletion in chronic HF enhances skeletal muscle energetics as reflected by shorter PCr recovery half-times (PCr t 1/2 ) on phosphorus magnetic resonance spectroscopy. Methods: We enrolled 40 patients (50% anemic) with chronic HF, New York Heart Association class ≥II, left ventricular ejection fraction ≤45%, and iron deficiency (ferritin<100 μg/L or 100–300 μg/L with transferrin saturation <20%). Subjects underwent stratified (anemic versus nonanemic) randomization (1:1) to a single, double-blinded, total dose infusion of iron isomaltoside or saline placebo with end points reassessed early at 2 weeks posttreatment to minimize confounding from exercise adaptation. The primary end point was PCr t 1/2 at 2 weeks. Secondary end points included ADP recovery half-time (ADP t 1/2; energetic marker), iron status, symptoms, Hb, exercise capacity, and safety. Results: In the total population, treatment groups were similar at baseline. At 2 weeks, iron isomaltoside improved PCr t 1/2 (adjusted difference, –6.8 s; 95% CI, 11.5 to –2.1; P =0.006), ADP t 1/2 (–5.3 s; 95% CI, –9.7 to –0.9; P =0.02), ferritin (304 ng/mL; 95% CI, 217–391; P <0.0001), transferrin saturation (6.8%; 95% CI, 2.7–10.8; P =0.002), New York Heart Association class (–0.23; 95% CI, –0.46 to –0.01; P =0.04), resting respiratory rate (–0.7 breaths/min; 95% CI, –1.2 to –0.2; P =0.009), and postexercise Borg dyspnea score (–2.0; 95% CI, –3.7 to –0.3; P =0.04), but not Hb (2.4 g/L; 95% CI, –3.5 to 8.4; P =0.41). Adverse events were similar between groups. In subgroup analyses, iron isomaltoside improved PCr t 1/2 in anemic (–8.4 s; 95% CI, –16.7 to –0.2; P =0.04) and nonanemic (–5.2 s; 95% CI, –10.6 to 0.2; P =0.06) cohorts. Conclusions: In patients with chronic HF and iron deficiency, a total repletion dose of iron isomaltoside given at a single sitting is well tolerated and associated with faster skeletal muscle PCr t 1/2 at 2 weeks, implying better mitochondrial function. Augmented skeletal muscle energetics might therefore be an important mechanism via which iron repletion confers benefits in chronic HF despite minimal Hb changes. Clinical Trial Registration: URL: https://www.clinicaltrialsregister.eu/ctr-search/trial/2012-005592-13/GB . Unique identifier: EudraCT 2012-005592-13.
Tumors become more homogeneous with treatment. An increase in T2-weighted MR imaging uniformity and a decrease in T2-weighted MR imaging entropy following NACT may provide an earlier indication of pCR than tumor size change.
Magnetic resonance cholangiopancreatography (MRCP) is a technique that has evolved over the past two decades. It continues to have a fundamental role in the non-invasive investigation of many pancreatico-biliary disorders. The purpose of this review is to summarise the key concepts behind MRCP, the different techniques that are currently employed (including functional and secretin-stimulated MRCP), the pitfalls the reader should be aware of, and the main clinical indications for its use.
BackgroundIt is known that individuals with bilateral spastic cerebral palsy (BSCP) have small and weak muscles. However, no studies to date have investigated intramuscular fat infiltration in this group. The objective of this study is to determine whether adults with BSCP have greater adiposity in and around their skeletal muscles than their typically developing (TD) peers as this may have significant functional and cardio-metabolic implications for this patient group.Methods10 young adults with BSCP (7 male, mean age 22.5 years, Gross Motor Function Classification System (GMFCS) levels I-III), and 10 TD young adults (6 male, mean age 22.8 years) took part in this study. 11 cm sections of the left leg of all subjects were imaged using multi-echo gradient echo chemical shift imaging (mDixon). Percentage intermuscular fat (IMAT), intramuscular fat (IntraMF) and a subcutaneous fat to muscle volume ratio (SF/M) were calculated.ResultsIntraMF was higher with BSCP for all muscles (p = 0.001-0.013) and was significantly different between GMFCS levels (p < 0.001), with GMFCS level III having the highest IntraMF content. IMAT was also higher with BSCP p < 0.001). No significant difference was observed in SF/M between groups.ConclusionYoung adults with BSCP have increased intermuscular and intramuscular fat compared to their TD peers. The relationship between these findings and potential cardio-metabolic and functional sequelae are yet to be investigated.
This UK Quantitative WB-DWI Technical Workgroup consensus provides guidance on maximising accuracy and reproducibly of quantitative WB-DWI for oncology. The consensus guidance can be used by researchers and clinicians to harmonise WB-DWI protocols which will accelerate clinical translation of WB-DWI-derived QIBs.
For many patients with kidney failure, the cause and underlying defect remain unknown. Here, we describe a novel mechanism of a genetic order characterized by renal Fanconi syndrome and kidney failure. We clinically and genetically characterized members of five families with autosomal dominant renal Fanconi syndrome and kidney failure. We performed genome-wide linkage analysis, sequencing, and expression studies in kidney biopsy specimens and renal cells along with knockout mouse studies and evaluations of mitochondrial morphology and function. Structural studies examined the effects of recognized mutations. The renal disease in these patients resulted from monoallelic mutations in the gene encoding glycine amidinotransferase (GATM), a renal proximal tubular enzyme in the creatine biosynthetic pathway that is otherwise associated with a recessive disorder of creatine deficiency. analysis showed that the particular mutations, identified in 28 members of the five families, create an additional interaction interface within the GATM protein and likely cause the linear aggregation of GATM observed in patient biopsy specimens and cultured proximal tubule cells. GATM aggregates-containing mitochondria were elongated and associated with increased ROS production, activation of the NLRP3 inflammasome, enhanced expression of the profibrotic cytokine IL-18, and increased cell death. In this novel genetic disorder, fully penetrant heterozygous missense mutations in trigger intramitochondrial fibrillary deposition of GATM and lead to elongated and abnormal mitochondria. We speculate that this renal proximal tubular mitochondrial pathology initiates a response from the inflammasome, with subsequent development of kidney fibrosis.
This is the first study investigating the optimal mDixon parameters for intramuscular fat quantification compared with MRS in vivo and in vitro.
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