We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the criterion of a muon ...number measured in an air shower, we successfully suppress 99.92% of the cosmic-ray background events with energies E>100 TeV. As a result, we observed 24 photonlike events with E>100 TeV against 5.5 background events, which corresponds to a 5.6σ statistical significance. This is the first detection of photons with E>100 TeV from an astrophysical source.
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Background and purpose
The clinical characteristics of colony stimulating factor 1 receptor (CSF1R) related adult‐onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) have been ...only partially elucidated.
Methods
Clinical data from CSF1R mutation carriers who had been seen at our institutions or reported elsewhere were collected and analysed using a specific investigation sheet to standardize the data.
Results
In all, 122 cases from 90 families with CSF1R mutations were identified. The mean age of onset was 43 years (range 18–78 years), the mean age at death was 53 years (range 23–84 years) and the mean disease duration was 6.8 years (range 1–29 years). Women had a significantly younger age of onset than men (40 vs. 47 years, P = 0.0006, 95% confidence interval 3.158–11.177). There was an age‐dependent penetrance that was significantly different between the sexes (P = 0.0013). Motor dysfunctions were the most frequent initial symptom in women whose diseases began in their 20s. Thinning of the corpus callosum, abnormal signalling in pyramidal tracts, diffusion‐restricted lesions and calcifications in the white matter were characteristic imaging findings of ALSP. The calcifications were more frequently reported in our case series than in the literature (54% vs. 3%). Seventy‐nine per cent of the mutations were located in the distal part of the tyrosine kinase domain of CSF1R (102 cases). There were no apparent phenotype−genotype correlations.
Conclusions
The characteristics of ALSP were clarified. The phenotype of ALSP caused by CSF1R mutations is affected by sex.
ObjectiveTo analyse clinicoepidemiological features of neuromyelitis optica in a large cohort and to compare the differences between onset age, gender and clinical phenotypes.MethodsAntiaquaporin-4 ...antibody (AQP4-ab) levels were tested in 2366 serum samples of patients diagnosed as having central nervous system inflammatory demyelinating disorders by their referring physicians. AQP4-ab was measured by indirect immunofluorescence staining using human AQP4-transfected HEK 293 cells. A blinded analysis was performed and was combined with clinical information.ResultsA total of 583 patients (91.4% women) were AQP4-ab-positive. The average onset age was 42.9±15.9 years. According to MRI studies, spinal-cord lesions were detected in 85.3% of the patients, longitudinally extensive transverse myelitis in 72.7% and cerebral lesions in 51.1%. Unilateral or bilateral blindness was observed in 16.2% of patients, 19.8% were associated with Sjögren syndrome, and 13.6% were associated with thyroid diseases. Myelin basic protein was detected in the cerebrospinal fluid of 57.5% patients. In addition, men presented with an older onset age, a greater number of brainstem MRI lesions and positive myelin basic protein in the cerebrospinal fluid. All child-onset patients (<15 years, n=9) presented with optic neuritis as the first symptom, while older-onset patients presented with myelitis. Twenty patients initially developed limited brain lesions, and seven of these patients did not develop optic or spinal lesions during the 1–5-year follow-up period.ConclusionsThe clinical characteristics of AQP4-ab-positive patients were similar. However, optic neuritis was more common in paediatric patients, while myelitis was more common in older patients. A small number of patients exhibited only cerebral, brainstem, or cerebellar lesions during the initial several years and lower Extended Disability Status Scale scores.
Abstract We investigated the behavior of red blood cells (RBCs) in a microchannel with stenosis using a confocal micro-PTV system. Individual trajectories of RBCs in a concentrated suspension of up ...to 20% hematocrit (Hct) were measured successfully. Results indicated that the trajectories of healthy RBCs became asymmetric before and after the stenosis, while the trajectories of tracer particles in pure water were almost symmetric. The asymmetry was greater in 10% Hct than in 20% Hct. We also investigated the effect of deformability of RBCs on the cell-free layer thickness by hardening RBCs using a glutaraldehyde treatment. The results indicated that deformability is the key factor in the asymmetry of cell-free layer thickness. Therefore, the motions of RBCs are influenced strongly by the Hct, the deformability, and the channel geometry. These results give fundamental knowledge for a better understanding of blood flow in microcirculation and biomedical microdevices.
Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia is a rare neurodegenerative disease resulting from mutations in the colony stimulating factor 1 receptor gene. Accurate ...diagnosis can be difficult because the associated clinical and MR imaging findings are nonspecific. We present 9 cases with intracranial calcifications distributed in 2 brain regions: the frontal white matter adjacent to the anterior horns of the lateral ventricles and the parietal subcortical white matter. Thin-section (1-mm) CT scans are particularly helpful in detection due to the small size of the calcifications. These calcifications had a symmetric "stepping stone appearance" in the frontal pericallosal regions, which was clearly visible on reconstructed sagittal CT images. Intrafamilial variability was seen in 2 of the families, and calcifications were seen at birth in a single individual. These characteristic calcification patterns may assist in making a correct diagnosis and may contribute to understanding of the pathogenesis of leukoencephalopathy.
ObjectiveThis study aimed to determine the spectrum of pathological involvement of the striatonigral (StrN) and olivopontocerebellar (OPC) systems in Japanese patients with multiple system atrophy ...(MSA). This study also aimed to compare the pathological spectrum of Japanese MSA patients with the previously reported results in British MSA patients.MethodsA semiquantitative pathological analysis of 50 MSA patients' brains that were referred to the Brain Research Institute, Niigata University, Japan, was performed. The severity of neuronal cell loss was determined as previously described by the study from the Queen Square Brain Bank (QSBB), UK.ResultsThe mean neuronal cell loss score was significantly higher in the OPC area than in the basal ganglia sites examined, except the dorsolateral putamen. The relative prevalence of pathological phenotypes showed that 40% of cases had OPC-predominant pathology, 18% had StrN-predominant pathology and the remaining (42%) had equivalent StrN and OPC pathology. None of the MSA cases had coexistent Lewy bodies in the dorsal motor nucleus of the vagus and the substantia nigra.ConclusionsIn contrast to the previously reported results involving British patients' brains from the QSBB (OPC-predominant pathology 17%, StrN-predominant pathology 34%, equivalent StrN and OPC pathology 49%), the results of the present study showed more pathological involvement of the OPC system than of the StrN system. The rarity of Lewy bodies may underlie the phenotypic expression of Japanese MSA. The present observations reflect the disequilibrium in the phenotype distribution between the two populations.
Spinocerebellar ataxia type 15 (SCA15) is a progressive neurodegenerative disorder characterized by pure cerebellar ataxia, very slow progression, and distinct cerebellar atrophy. The locus for SCA15 ...was first mapped to 3p24.2-3pter in an Australian family. We have subsequently mapped two Japanese families presenting with ataxia and postural tremor of the head, arm, or trunk to the SCA15 locus. Recently, partial deletions involving both the type 1 inositol 1,4,5-triphosphate receptor (ITPR1) and sulfatase modifying factor 1 (SUMF1) genes have been identified in Australian and British families with SCA15.
We conducted fine haplotype analysis on the region including ITPR1. To identify the deletion, we conducted gene dosage analysis and array-based comparative genomic hybridization (aCGH) analysis. Gene expression analysis was performed using quantitative real-time reverse transcription PCR. Mutational analyses of ITPR1 and SUMF1 were also performed.
We have identified a 414-kb deletion including the entire ITPR1 and exon 1 of SUMF1 in patients in family A. The expression levels of ITPR1 and SUMF1 mRNAs of the patient were half those of the normal control. Furthermore, in family B, we have identified a C-to-T substitution at position 8581 of ITPR1, resulting in the amino acid substitution of leucine for proline at codon 1059, which is highly conserved among species.
Our results strongly confirm that ITPR1 is the causative gene for SCA15 and suggest that we need to investigate the point mutation in ITPR1 in the patients with autosomal dominant cerebellar ataxia and tremor.
Fluid chemistry and microbial community patterns in chimney habitats were investigated in two hydrothermal fields located at the Central Indian Ridge. Endmember hydrothermal fluid of the Solitaire ...field, located ~3 km away from the spreading center, was characterized by moderately high temperature (307°C), Cl depletion (489 mm), mildly acidic pH (≥4.40), and low metal concentrations (Fe ≤ 105 μm and Mn = 78 μm). Chloride depletion indicates that the subseafloor source fluid had undergone phase separation at temperatures higher than ~390°C while the metal depletion was likely attributable to fluid alteration occurring at a venting temperature of around 307°C. These different temperature conditions suggested from fluid chemistry might be associated with an off‐spreading center location of the field that allows subseafloor fluid cooling prior to seafloor discharge. The microbial community in the chimney habitat seemed comparable to previously known patterns in typical basalt‐hosted hydrothermal systems. Endmember hydrothermal fluid of the Dodo field, standing on center of the spreading axis, was characterized by high H2 concentration of 2.7 mm. The H2 enrichment was likely attributable to fresh basalt–fluid interaction, as suggested by the nondeformed sheet lava flow expansion around the vents. Thermodynamic calculation of the reducing pyrite–pyrrhotite–magnetite (PPM) redox buffer indeed reproduced the H2 enrichment. The quantitative cultivation test revealed that the microbial community associated with the hydrothermal fluid hosted abundant populations of (hyper)thermophilic hydrogenotrophic chemolithoautotrophs such as methanogens. The function of subseafloor hydrogenotrophic methanogenic populations dwelling around the H2‐enriched hydrothermal fluid flows was also inferred from the 13C‐ and D‐depleted signature of CH4 in the collected fluids. It was observed that the hydrothermal activity of the Dodo field had ceased until 2013.