Exome sequencing identifies a TCF4 mutation in a Chinese pedigree with symmetrical acral keratoderma

BACKGROUND

Symmetrical acral keratoderma (SAK) is a rare skin disorder and its pathogenesis and inheritability are unknown.

OBJECTIVES

To investigate the inheritance and pathogenesis of SAK.

METHODS

Four SAK cases occurred in a four-generation Chinese family. Exome sequencing identified SNPs with potential SAK-related mutations, and a potentially responsible gene transcription factor 4 (TCF4) was identified. TCF4 was then sequenced in all 11 family members, and pedigree analysis was performed. Histopathology and immunohistochemistry evaluated TCF4 expression in skin lesions. The gene mutation was investigated in human keratinocytes for keratin-related protein expression.

RESULTS

A novel heterozygous missense mutation, c.85C>A (p.Pro29Thr) was found in TCF4. The mutation showed autosomal dominant inheritance and perfectly cosegregated with the SAK phenotype in all family members. In skin lesions, TCF4 was present in the cytoplasm and membranes of the basal layer, the stratum spinosum and the stratum granulosum of the epidermis. The mutant TCF4 induced overexpression of differentiation markers including KRT1, KRT14, loricrin and involucrin.

CONCLUSIONS

A SAK-related gene mutation in TCF4 may function through transcriptional regulation of keratin.

[Laryngeal endoscopic cricopharyngeal myotomy for cricopharyngeal achalasia post stroke]

Objective: To explore the safety and validity of endoscopic cricopharyngeal myotomy in patients with cricopharyngeal achalasia. Methods: A total of 19 patients with cricopharyngeal achalasia suffered from sustained dysphagia were enrolled in this study. The patients were divided into transcervical cricopharyngeal myotomy(CPM) group and endoscopic CPM (ECPM) group. Swallowing function and complications were evaluated.SPSS7.0 software was used to analyze the data. Results: The swallowing function improved significantly in seven patients in ECPM group, and 9 patients improved in CPM group.The video fluoroscopic swallowing study(VFSS)-swallowing score, VFSS-aspiration score and drinking test score were (3.1±1.1), (3.4±0.8) and (2.0±0.6)in post-ECPM, (3.4±1.4), (3.0±0.9) and (2.2±0.6)in post-CPM. No statistical difference was found in validity between CPM group and ECPM group(t=-0.435, t=1.086, t=-0.607, P>0.05). No statistical difference was observed on the occurrence of complication between two groups. Only one patient had subcutaneous emphysema after operation in ECPM. Conclusions: New surgical instruments and endoscopic surgical technique were safe and effective for cricopharyngeal achalasia. Because these instruments are cheaper, laryngeal endoscopic cricopharyngeal myotomy is easier to be popularized more easily than microscopic laser assistted CPM.

HLA-B*40:356, identified by next-generation sequence based typing in a Chinese tuberculosis patient

HLA-B*40:356 differs from B*40:02:01 by only one nucleotide transition, C>A 1040 in exon 6.

Measurement of the Neutrino Mixing Angle θ_{23} in NOvA

This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of 6.05×10^{20} protons on target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal θ_{23} mixing (θ_{23}=π/4). Assuming the normal mass hierarchy, we find Δm_{32}^{2}=(2.67±0.11)×10^{-3}  eV^{2} and sin^{2}θ_{23} at the two statistically degenerate values 0.404_{-0.022}^{+0.030} and 0.624_{-0.030}^{+0.022}, both at the 68% confidence level. Our data disfavor the maximal mixing scenario with 2.6σ significance.

[Distribution of electroencephalograph power density in patients with severe obstructive sleep apnea during different sleep stages]

Objective: To investigate the variation of electroencephalograph(EEG) power density during different sleep stages in OSA for understanding of the mechanisms underlying the brain dysfunction in OSA as well as its earlier diagnosis and treatment. Methods: Sixteen-channel EEGs from OSA patients and normal controls in stage wake, sleep stage 1, sleep stage 2, sleep stage 3 and rapid eye movement stage were analyzed by time-frequency analysis method. The EEG power density in different frequency bands (including δ, θ, α, σ, β and γ) was respectively compared between the 2 groups. The correlation between the variation in the EEG power and primary indices of polysomnography was further analyzed. Results: The EEG power density in δ band in stage wake [OSA: (0.82±0.13) μV(2)/Hz, Control: (0.66±0.02) μV(2)/Hz, t=4.309, P<0.05], stage 1 [OSA: (1.28±0.07) μV(2)/Hz, Control: (0.92±0.04) μV(2)/Hz, t=-3.369, P<0.05] and stage 3 [OSA: (2.74±0.22) μV(2)/Hz, Control: (2.04±0.07) μV(2)/Hz, t=-2.669, P<0.05] was significantly higher in OSA, compared with that in the control. Statistical analysis showed that the EEG power density was significantly higher in frontal and central regions in stage wake [frontal: OSA: (0.90±0.02) μV(2)/Hz, Control: (0.66±0.02) μV(2)/Hz, t=8.539, P<0.01; central: OSA: (1.15±0.06) μV(2)/Hz, Control: (0.72±0.02) μV(2)/Hz, t=6.669, P<0.01] and stage 1 [frontal: OSA: (1.23±0.03) μV(2)/Hz, Control: (0.99±0.03) μV(2)/Hz, t=5.983, P<0.01; central: OSA: (1.52±0.05) μV(2)/Hz, Control: (1.14±0.04) μV(2)/Hz, t=5.714, P<0.01], as well as central region in stage 3 [OSA: (3.24±0.17) μV(2)/Hz, Control: (2.71±0.08) μV(2)/Hz, t=2.707, P<0.05]. The correlation analysis showed that the power density in central region in stage 1 and stage 3 was positively correlated with arousal index (r=0.877 in stage 1, 0.656 in stage 3), implying that sleep fragmentation was closely related to the variation of EEG power density during nocturnal sleep in OSA. Conclusions: The feature stages for OSA are stage wake, stage 1 and stage 3. The EEG power density in OSA (δ band) was significantly higher than that in the control. The EEG power density in OSA and the control shows differences in frontal and central regions in stage wake and stage 1, as well as in central region in stage 3. The results indicate that low-frequency EEG power density giving priority to frontal area and central area has improved in severe OSA, which may be related to the neurologic deficits in corresponding brain areas.

Transition Metal Chelator Induces Progesterone Production in Mouse Cumulus-Oocyte Complexes and Corpora Lutea

Progesterone production is upregulated in granulosa cells (cumulus and mural) after the LH surge, but the intra-follicular mechanisms regulating this transition are not completely known. Recent findings show that the transition metal chelator, N,N,N',N'-tetrakis-(2-pyridylmethyl)-ethylenediamine (TPEN), impairs ovarian function. In this study, we provide evidence that chelating transition metals, including zinc, enhances progesterone production. The findings show that TPEN (transition metal chelator) increases abundance of Cyp11a1 and Star messenger RNA (mRNA) between 8- and 20-fold and progesterone production more than 3-fold in cultured cumulus-oocyte complexes (COC). Feeding a zinc-deficient diet for 10 days, but not 3 days, increased Star, Hsd3b, and prostaglandin F2 alpha receptor (Ptgfr) mRNA ~2.5-fold, suggesting that the effect of TPEN is through modulation of zinc availability. Progesterone from cumulus cells promotes oocyte developmental potential. Blocking progesterone production with epostane during maturation reduced subsequent blastocyst formation from 89 % in control to 18 % in epostane-treated complexes, but supplementation with progesterone restored blastocyst developmental potential to 94 %. Feeding a zinc-deficient diet for 5 days before ovulation did not affect the number of CL, STAR protein, or serum progesterone. However, incubating luteal tissue with TPEN increased abundance of Star, Hsd3b, and Ptgfr mRNA 2-3-fold and increased progesterone production 3-fold. TPEN is known to abolish SMAD2/3 signaling in cumulus cells. However, treatment of COC with the SMAD2/3 phosphorylation inhibitor, SB421542, did not by itself induce steroidogenic transcripts but did potentiate EGF-induced Star mRNA expression. Collectively, the results show that depletion of transition metals with TPEN acutely enhances progesterone biosynthesis in COC and luteal tissue.

Rapid in-focus corrections on quantitative amplitude and phase imaging using transport of intensity equation method

Transport of intensity equation (TIE) method can acquire sample phase distributions with high speed and accuracy, offering another perspective for cellular observations and measurements. However, caused by incorrect focal plane determination, blurs and halos are induced, decreasing resolution and accuracy in both retrieved amplitude and phase information. In order to obtain high-accurate sample details, we propose TIE based in-focus correction technique for quantitative amplitude and phase imaging, which can locate focal plane and then retrieve both in-focus intensity and phase distributions combining with numerical wavefront extraction and propagation as well as physical image recorder translation. Certified by both numerical simulations and practical measurements, it is believed the proposed method not only captures high-accurate in-focus sample information, but also provides a potential way for fast autofocusing in microscopic system.

FBXL4 defects are common in patients with congenital lactic acidemia and encephalomyopathic mitochondrial DNA depletion syndrome

Mutations in FBXL4 have recently been recognized to cause a mitochondrial disorder, with clinical features including early onset lactic acidosis, hypotonia, and developmental delay. FBXL4 sequence analysis was performed in 808 subjects suspected to have a mitochondrial disorder. In addition, 28 samples from patients with early onset of lactic acidosis, but without identifiable mutations in 192 genes known to cause mitochondrial diseases, were examined for FBXL4 mutations. Definitive diagnosis was made in 10 new subjects with a total of 7 novel deleterious variants; 5 null and 2 missense substitutions. All patients exhibited congenital lactic acidemia, most of them with severe encephalopathic presentation, and global developmental delay. Overall, FBXL4 defects account for at least 0.7% (6 out of 808) of subjects suspected to have a mitochondrial disorder, and as high as 14.3% (4 out of 28) in young children with congenital lactic acidosis and clinical features of mitochondrial disease. Including FBLX4 in the mitochondrial diseases panel should be particularly important for patients with congenital lactic acidosis.

125 INCOMPLETE COMPENSATORY UP-REGULATION OF X-LINKED GENES IN BOVINE GERMLINE, EARLY EMBRYOS, AND SOMATIC TISSUES

The maintenance of a proper gene dosage is essential in cellular networks. To resolve the dosage imbalance between eutherian females (XX) and male (XY), X chromosome inactivation (XCI) occurs in females, while X-chromosome dosage compensation up-regulates the active X to balance its expression with that of autosome pairs [Ohno’s hypothesis; Ohno 1967 Sex Chromosomes and Sex-linked Genes (Springer-Verlag), p. 99]. These phenomena have been well studied in humans and mice, despite many controversies over the existence of such up-regulation. Using RNA sequencing data, we determined X chromosome dosage compensation in the bovine by analysing the global expression profiles of germ cells, embryos, and somatic tissues. Eight bovine RNA-seq data sets were obtained in from the Gene Expression Omnibus, covering bovine immature/mature oocytes (GSE59186 and GSE52415), pre-implantation conceptuses (GSE59186, GSE52415, and GSE56513), extra-embryonic tissues (PRJNA229443), and male/female somatic tissues (GSE74076, GSE63509, PRJEB6377, and GSE65125). The RNAseq data were trimmed and non-uniquely (paralogs included) mapped to the bovine reference genome assembly UMD3.1.1 using Hisat2 (version 2.0.5) aligner. The mRNA level of each gene, estimated by transformed transcripts per kilobase million was quantified by IsoEM (version 1.1.5). These RNA-seq data sets represented 4 chromosome scenarios in cells: XXXX:AAAA (diploid immature oocyte with DNA duplication), XX:AA (haploid mature oocyte with DNA duplication), XX:AA and X:AA (gradual changed X status in bovine pre-implantation conceptuses), and X:AA (extra-embryonic tissues and somatic cells in female with one active X or XY male) were analysed for dosage compensation. A total of 959 X-linked genes and 20,316 autosome genes were used to calculate the relative X to autosomal gene (A) expression (RXE): log2 (X expression) − log2 (A expression). The following dosage determinations were made: RXE values ≥ 0: complete dosage compensation (or X: A ratio ≥ 1); RXE values < 0: in-complete dosage compensation; RXE value = −1: no dosage compensation (or X: A ratio = 0.5). Our analyses showed a decreased RXE after fertilization, from −0.33 in matured oocytes to −0.50 at the 2-cell stage, indicating that the sperm that undergo meiotic sex chromosome inactivation (MSCI) bring in inactive X chromosomes to the matured oocytes. Subsequently, the activation of the bovine embryonic genome at the 4- to 8-cell stage increased RXE from −0.54 to −0.05. This was followed by a sharp RXE decline from −0.02 at the 16-cell stage, 0.1 at the 32-cell stage to −0.29 at the compact morula stage, which is known as paternal X inactivation stage in the bovine. Finally, RXE was stabilised from blastocysts −0.19 through the Day 19 conceptuses −0.25 to somatic tissue average −0.21 with a pattern of incomplete X compensation. These findings support X expression up-regulation as proposed by Ohno. No significant RXE differences were observed between bovine female and male somatic tissues, further supporting Ohno’s hypothesis, which predicts a balance in the expression of X-linked genes to that of autosomes. This study confirms Ohno’s hypothesis of X dosage compensation in bovine germ cells, early embryos, and somatic tissues.

130 A CATALOG OF REFERENCE GENES WITH HIGH, MEDIUM, AND LOW LEVELS OF EXPRESSION DURING BOVINE IN VIVO PRE-IMPLANTATION DEVELOPMENT

Appropriate reference genes for accurate normalization in RT-PCR are essential for the study of gene expression. Ideal reference genes should not only have stable expression across stages of embryo development, but also be expressed at comparable levels to the target genes. Using RNA-seq data from in vivo-produced bovine oocytes and embryos from the 2-cell to blastocyst stage (Jiang et al., 2014 BMC Genomics 15, 756), we tried to establish a catalogue of all reference genes for RT-PCR analysis. One-way ANOVA generated 4055 genes that did not differ across stages. To reduce this list, we used the entire RNA-seq data set and first removed genes with a FPKM (fragments per kilobase of transcript per million mapped reads) of <1, and then rescaled each gene’s expression values within a range of 0 to 1. We subsequently calculated the expression variance for each gene across all stages. By assuming that the calculated variances follow a Gaussian distribution and that the majority of the genes do not have a stable expression level, a gene was classified as a reference if its variance significantly deviated (P < 0.05) from these assumptions. We identified 346 potential reference genes, all of which were among the candidates from the ANOVA analysis. We arbitrarily assigned genes in this list to high (FPKM ≥ 100), medium (10 < FPKM < 100), and low expression levels (FPKM ≤ 10), and 37, 154, and 155 genes, respectively, fell into these groups. Surprisingly, none of the commonly used reference genes, such as GAPDH, PPIA, ACTB, PRL15, GUSB, and H3F2A, were identified as being stably expressed across in vivo development. This is consistent with findings of prior RT-PCR studies (Robert et al. 2002 Biol. Reprod. 67, 1465–1472; Ross et al. 2010 Cell Reprogram. 12, 709–717). The following gene ontology terms were significantly enriched for the 346 genes: cell cycle, translation, transport, chromatin, cell division, and metabolic process, indicating that the early embryos maintained constant levels of genes involved in fundamental biological functions. Finally, we performed RT-PCR to validate the RNA-seq results using different bovine in vivo-derived oocytes and embryos (n = 3/stage). We successfully validated 10 selected genes, including those in the high (CS, PGD, and ACTR3), medium (CCT5, MRPL47, COG2, CRT9, and HELLS), and low expression groups (CDC23 and TTF1). In conclusion, we recommend the use of reference genes that are expressed at comparable levels to target genes. This study offers a useful resource to aid in the appropriate selection of reference genes, which will improve the accuracy of quantitative gene expression analyses across bovine embryo pre-implantation development.

127 ABUNDANCE OF mRNA FOR HISTONE VARIANTS, HISTONE, AND DNA MODIFICATION ENZYMES IN BOVINE IN VIVO OOCYTES AND PRE-IMPLANTATION EMBRYOS

During early embryogenesis, chromatin composition and structure undergo dramatic changes due to replacement of canonical histones by histone variants, post-translational modifications of histones, and changes in DNA methylation. These dynamics of chromatin play important roles in the regulation of gene expression and development of embryonic cells. Our goal here is to describe the above-mentioned changes using recently established transcriptome profiles of bovine in vivo-produced oocytes and pre-implantation embryos (Jiang et al. 2014 BMC Genomics, 15, 1). Ten multiparous Holstein cows were synchronized and superovulated. Artificial insemination was conducted at 12 and 24 h post-standing heat using semen from bulls of proven fertility. In vivo-matured oocytes and 2- to 16-cell stage embryos were collected at 30 h, and 2 to 4 days after oestrus by oviducal flushing. Early morulae, compact morulae, and blastocysts were collected by non-surgical uterine flushing on days 5, 6, and 7 after oestrus. Single-cell deep sequencing libraries were prepared from oocytes/embryos (2 samples/stage) using a SOLiDTM Total RNA-seq Kit (Thermo Fisher Scientific, Waltham, MA, USA) following the manufacturer’s instructions and sequenced on a 5500xl Genetic Analyzer. The reproducibility of the preparation and sequencing methods were indicated by high Pearson correlation efficiencies between the replicates. Sequencing reads were normalized to transcripts per million as final results after trimming and mapping of the reads. We found that 8, 8, 7, 13, 10, 2, and 2 out of the 14, 52, 22, 31, 23, 4, and 3 annotated histone variants, histone methyl-tranferases, histone demethylases, histone acetyl-tranferases, histone deacetylases, DNA methyl-transferases, and DNA demethylases, respectively, were highly abundant (mean transformed transcripts per kilobase million > 50) in at least one of the pre-implantation development stages studied. Among histone variants with high mRNA abundance, H1FOO, H3F3A, and H3F3B were highly stored in oocytes, whereas other variants such as H2AFJ, H2AFV, H2AFX, H2AFY, H2AFZ, and CENPA were largely transcribed after the embryonic genome activation. H3F3A and H3F3B, however, were maintained at relatively high levels throughout pre-implantation development. Additionally, the mRNA for histone acetyl-transferases, TADA2A and TADA1; histone deacetylase, HDAC1 and HDAC3; histone methyl-transferases, EED and PRMT5; histone demethylase, KDM1A, were more abundant than others. It was also found that oocytes stored a large amount of DNA methyl-transferase, DNMT1, which degraded gradually after fertilization. Overall, in vivo-produced oocytes and early embryos contained more mRNA for histone-modifying enzymes than those for DNA modification. Taken together, our results suggest that although there are widely recognised and dramatic changes in embryonic DNA methylation through both active and passive mechanisms, the pre-implantation embryos may be more engaged in modifying histones than DNA.

Losartan Improves Palmitate-Induced Insulin Resistance in 3T3-L1 Adipocytes Through Upregulation of Src Phosphorylation

Angiotensin II type 1 receptor blocker losartan has shown strongly anti-insulin resistance properties in vivo and in vitro; however, the underlying mechanisms are poorly understood. In this study, we demonstrate that losartan administration increased phosphorylation of Akt and its downstream Akt substrate of 160 kDa (AS160), enhanced plasma membrane translocation of glucose transporter type 4 (GLUT4), and increased glucose uptake, along with increased Src phosphorylation as well as reduced expression of docking protein 1(DOK1) in palmitate-treated 3T3-L1 adipocytes. The beneficial impacts of losartan on insulin signaling were diminished in Src-deficient 3T3-L1 adipocytes. In addition, suppressed expression of DOK1 by losartan was abolished by Src knockdown. Our results suggest that anti-insulin resistance ability of losartan is mediated by Src/DOK1/Akt pathway.

Outcomes of standard dose EC-MPS with low exposure to CsA in DCD renal transplantation recipients with DGF

AIMS

The lower limit of exposure to cyclosporine A (CsA) has not yet been established in donation after cardiac death (DCD) renal transplantation recipients with delayed graft function (DGF) receiving enteric-coated mycophenolate sodium (EC-MPS) therapy. Stable and adequate mycophenolic acid (MPA) dosing may facilitate lower CsA exposure after DCD renal transplantation in recipients with DGF without compromising safety.

METHODS

A 12-month, single-centre open-label prospective trial was performed in our centre. According to their DGF risk index using the previous DGF prediction models, we divided up the patients on oral CsA into either a DGF group (n = 26) and no DGF group (n = 48). All of the patients initially received the standard EC-MPS dosing (1440 mg/day). The initial dose of CsA in the low risk of DGF group was 4.5 mg/kg/day and in the high risk of DGF group was 2.5 mg/kg/day. Efficacy parameters, safety and tolerability were assessed over a 12-month study period.

RESULTS

The incidence of DGF was 18.5% in the 162 DCD recipients. Between the DGF group and the no DGF group, the 1-year patient survival and graft survival were not significantly different. The incidence of BPAR was higher in the DGF group (26.9% vs. 8.3%, p = 0.032). Most patients in the DGF group had recovery of renal function after 1 month. The adverse events between the two groups were not significantly different. The daily EC-MPS doses of the DGF group were significantly higher than the no DGF group before the 6-month follow-up period. There were no significant differences between the two groups regarding the mean AUC levels during the follow-up period.

CONCLUSIONS

These results show that low expose CsA with standard dosing of EC-MPS and thymoglobulin was efficacious, safe and well-tolerated in DCD renal transplant recipients with DGF in China. Furthermore, stable and adequate MPA exposure helped to reduce the dose of and exposure to CsA. Thus, this may lead to less-induced nephrotoxicity and better renal function recovery.

[The effects of P - glycoprotein expression induced by ulinastatin on HK - 2 cells damage induced by paraquat]

Objective: To investigate the protective effect of P-glycoprotein up-regulated by ulinastatin (UTI) on HK-2 cells during paraquat (PQ) -induced injury and its underlying mechanisms. Methods: The re- search was divided into two parts. The first part of the research was divided into normal control group, PQ group, UTI+PQ group, UTI control group. The second part of the research was divided into negative virus group (including control group, PQ group, PQU+TI group, UTI group) and P-gp siRNA group (including control group, PQ group, PQU+TI group, UTI group) . Negative virus group: the cells were transfected into the blank virus; siRNA P-gp group: the cells were transfected with P-gp siRNA virus. HK-2 cells were routinely cultured. After 800 μmol/L PQ treatment, the changes of P-gp protein levels in the HK-2 cells were determined by West-ern-blot (WB) . Then, transfected lentivirus bringing P-gp silent gene, the cell viability was determined by CCK-8 assay, the expression of P-gp in the cells after transfection was detected by WB and the concentration of PQ in HK-2 cells were measured by high performance liquid chromatography (HPLC) . Results: Compared with the normal control group, the P-gp expression of PQ group had no significantly changes (P>0.05) . Compared with the PQ group, the P-gp expression of UTI+PQ group significantly increased (P>0.05) . Compared with the corre-sponding control siRNA group, the P-gp siRNA group had no significantly changes in cell viability (P>0.05) . and significantly decreased in P-gp expression. Compared with the corresponding control siRNA group, the P-gp siRNA group had no significantly changes in PQ concentration in HK-2 cell (P>0.05) , but compared with P-gp siRNA PQ group, the PQ concentration of P-gp siRNA PQ+UTI group significantly decrease (P<0.05) . Conclusion: UTI significantly reduced the accumulation of PQ in HK-2 cells and increased the viability of HK-2 cells in vitro may be not by increased P-gp activity. UTI could significantly reduce HK-2 cell injury induced by PQ in vitro and improve the survival rate of HK-2 cells. It may not be related to the up regulation of P-gp expres-sion.

Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^{2}2θ_{μe} are set over 6 orders of magnitude in the sterile mass-squared splitting Δm_{41}^{2}. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm_{41}^{2}<0.8  eV^{2} at 95%  CL_{s}.

Search for Sterile Neutrinos Mixing with Muon Neutrinos in MINOS

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a ν_{μ}-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56×10^{20} protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ_{24} and Δm_{41}^{2} and set limits on parameters of the four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |U_{μ4}|^{2} and |U_{τ4}|^{2}, under the assumption that mixing between ν_{e} and ν_{s} is negligible (|U_{e4}|^{2}=0). No evidence for ν_{μ}→ν_{s} transitions is found and we set a world-leading limit on θ_{24} for values of Δm_{41}^{2}≲1  eV^{2}.

From the Blood to the Central Nervous System: A Nanoparticle's Journey Through the Blood-Brain Barrier by Transcytosis

Designing nanoparticles that effectively enter the central nervous system (CNS) rapidly and without alteration is one of the major challenges in the use of nanotechnology for the brain. In this chapter, we explore the process of transcytosis, a receptor-mediated transport pathway that permits endogenous macromolecules to enter the CNS by crossing the blood-brain barrier. Transcytosis across the blood-brain barrier involves a number of distinct stages, including receptor binding, endocytosis into a transport vesicle, trafficking of the vesicle to the opposite side of the cell, and finally exocytosis and release of cargo. For each stage, we discuss the current knowledge on biological, physiological, and physical factors that influence nanoparticle transit through that stage of transcytosis, with implications for nanoparticle design. Finally, we look at the current progress in designing nanoparticles that exploit transcytosis for CNS delivery.