4,109 research outputs found

    PRRT2 gene variant in a child with dysmorphic features, congenital microcephaly, and severe epileptic seizures: genotype-phenotype correlation?

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    BACKGROUND: Mutations in Proline-rich Transmembrane Protein 2 (PRRT2) have been primarily associated with individuals presenting with infantile epilepsy, including benign familial infantile epilepsy, benign infantile epilepsy, and benign myoclonus of early infancy, and/or with dyskinetic paroxysms such as paroxysmal kinesigenic dyskinesia, paroxysmal non-kinesigenic dyskinesia, and exercise-induced dyskinesia. However, the clinical manifestations of this disorder vary widely. PRRT2 encodes a protein expressed in the central nervous system that is mainly localized in the pre-synaptic neurons and is involved in the modulation of synaptic neurotransmitter release. The anomalous function of this gene has been proposed to cause dysregulation of neuronal excitability and cerebral disorders. CASE PRESENTATION: We hereby report on a young child followed-up for three years who presents with a spectrum of clinical manifestations such as congenital microcephaly, dysmorphic features, severe intellectual disability, and drug-resistant epileptic encephalopathy in association with a synonymous variant in PRRT2 gene (c.501Cā€‰>ā€‰T; p.Thr167Ile) of unknown clinical significance variant (VUS) revealed by diagnostic exome sequencing. CONCLUSION: Several hypotheses have been advanced on the specific role that PRRT2 gene mutations play to cause the clinical features of affected patients. To our knowledge, the severe phenotype seen in this case has never been reported in association with any clinically actionable variant, as the missense substitution detected in PRRT2 gene. Intriguingly, the same mutation was reported in the healthy father: the action of modifying factors in the affected child may be hypothesized. The report of similar observations could extend the spectrum of clinical manifestations linked to this mutation

    IsaB Inhibits Autophagic Flux to Promote Host Transmission of Methicillin-Resistant Staphylococcus aureus.

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    Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major nosocomial pathogen that is widespread in both health-care facilities and in the community at large, as a result of direct host-to-host transmission. Several virulence factors are associated with pathogen transmission to naive hosts. Immunodominant surface antigen B (IsaB) is a virulence factor that helps Staphylococcus aureus to evade the host defense system. However, the mechanism of IsaB on host transmissibility remains unclear. We found that IsaB expression was elevated in transmissible MRSA. Wild-type isaB strains inhibited autophagic flux to promote bacterial survival and elicit inflammation in THP-1 cells and mouse skin. MRSA isolates with increased IsaB expression showed decreased autophagic flux, and the MRSA isolate with the lowest IsaB expression showed increased autophagic flux. In addition, recombinant IsaB rescued the virulence of the isaB deletion strain and increased the group A streptococcus (GAS) virulence in vivo. Together, these results reveal that IsaB diminishes autophagic flux, thereby allowing MRSA to evade host degradation. These findings suggest that IsaB is a suitable target for preventing or treating MRSA infection

    Controlled release of human growth hormone fused with a human hybrid Fc fragment through a nanoporous polymer membrane

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    Nanotechnology has been applied to the development of more effective and compatible drug delivery systems for therapeutic proteins. Human growth hormone (hGH) was fused with a hybrid Fc fragment containing partial Fc domains of human IgD and IgG(4) to produce a long-acting fusion protein. The fusion protein, hGH-hyFc, resulted in the increase of the hydrodynamic diameter (ca. 11 nm) compared with the diameter (ca. 5 nm) of the recombinant hGH. A diblock copolymer membrane with nanopores (average diameter of 14.3 nm) exhibited a constant release rate of hGH-hyFc. The hGH-hyFc protein released in a controlled manner for one month was found to trigger the phosphorylation of Janus kinase 2 (JAK2) in human B lymphocyte and to exhibit an almost identical circular dichroism spectrum to that of the original hGH-hyFc, suggesting that the released fusion protein should maintain the functional and structural integrity of hGH. Thus, the nanoporous release device could be a potential delivery system for the long-term controlled release of therapeutic proteins fused with the hybrid Fc fragment.X111313sciescopu

    Measured and calculated seismic velocities and densities for granulites from xenolith occurrences and adjacent exposed lower crustal sections: A comparative study from the North China craton

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    Granulites from the Neogene xenolith-bearing Hannuoba alkaline basalt and from the Manjinggou-Wayaokou exposed lower crustal section in the Archean Huai'an terrain, which occurs within and surrounds the Hannuoba basalt, provide a unique opportunity for a comparative study on petrophysical properties and composition of the lower crust represented by these two types of samples. P and S wave velocities and densities of 12 Hannuoba lower crustal xenoliths and one associated spinel lherzolite xenolith as well as nine granulites and granulite-facies metasedimentary rocks from the Archean Huai'an terrain were measured in laboratory at pressures up to 600 MPa and temperatures up to 600Ā°C. Calculations of P and S wave velocities were also made for the same suite of samples based on modal mineralogy and single-crystal velocities whose variations with composition are considered by using microprobe analyses and velocities of end members. The measured and calculated Vp at room temperature and 600 MPa, where the microcrack effect is considered to be almost eliminated, agree within 4% for rocks from the Manjinggou-Wayaokou section and the adjacent Wutai-Jining upper crustal to upper lower crustal section. In contrast, the xenoliths show systematically lower measured Vp by up to 15% relative to calculated velocities, even if decompression-induced products of kelyphite and glass are taken into account. The lower measured velocities for xenoliths are attributed to grain boundary alteration and residual porosity. This implies that although granulite xenoliths provide direct information about lower crustal constitution and chemical composition, they are not faithful samples for studying in situ seismic properties of the lower crust in terms of measured velocities due to alterations during their entrainment to the surface, which changes their physical properties significantly. In this respect, granulites from high-grade terrains are better samples because they are not subjected to significant changes during their slow transport to the surface and because physical properties depend primarily on mineralogy in addition to pressure and temperature. On the other hand, calculated velocities for granulite xenoliths are consistent with velocities for granulites from terrains, suggesting that they can be also used to infer lower crust composition by correlating with results from seismic refraction studies. Copyright 2000 by the American Geophysical Union.published_or_final_versio

    Trinitrophenol Reactive T-Cell Hybridomas Recognize Antigens That Require Antigen Processing

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    Protein antigens must be taken up, processed, and displayed on the surface of antigen-presenting cells in association with major histocompatibility complex molecules before they can be recognized by T cells. Whether recognition of the haptens used to study allergic contact hypersensitivity in murine models similarly requires processing has not been determined. We analyzed whether presentation of trinitrophenol to trinitrophenol reactive T-cell hybridomas requires antigen processing by studying the effects of inhibitors of antigen processing and presentation on tile ability of a syngeneic B-cell tumor (A20) to present trinitrophenol to a series of interleukin-2 producing, trinitrophenol specific, major histocompatibility complex class II-restricted T-cell hybridomas.The ability of trinitrophenol modified A20 cells to stimulate the hybridomas was completely inhibited by rnonoclonal, anti-trinitrophenol, or anti-Ia antibodies and was significantly reduced by paraformaldehyde fixation immediately after trinitrophenol modification. Trinitrophenol-modified A20 cultured at 37Ā°C for 2h prior to fixation was significantly more effective at stimulating the hybridomas than trinitrophenol-modified A20 to present trinitrophenol was inhibited by chloroquine. Paraformaldehyde fixation and chloroquine treatment had similar effects on the ability of trinitrophenol modified lymph node dendritic cells to stimulate the trinitrophenol specific hybridomas. Paraformaldehyde fixation and chloroquine treatment had similar effects on the ability of A20 cells to present ovalbumin to ovalbumin-specific hybridomas as they had on the ability of trinitrophenol modified A20 cells to present trinitrophenol to the trinitrophenol specific hybridomas. One of seven T-cell hybridomas responded to trinitrophenol modified ovalbumin but not other trinitrophenol modified proteins. These results suggest that, at least in part, T cells in the contact hypersensitivity response to trinitrophenol recognize antigens that require processing and that trinitrophenol modified proteins can be recognized

    Surge of Typhoid Intestinal Perforations as Possible Result of COVID-19-Associated Delays in Seeking Care, Madagascar.

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    During the coronavirus disease pandemic, we observed a 6.4-fold increase in typhoid intestinal perforation incidence in Antananarivo, Madagascar. Thirteen perforations occurred within 6 months (February 2020-July 2020), compared with 13 perforations during the previous 41 months (August 2016-January 2020). The increase may be attributable to delayed healthcare seeking during the pandemic

    Toward production of jet fuel functionality in oilseeds: identification of FatB acyl-acyl carrier protein thioesterases and evaluation of combinatorial expression strategies in \u3ci\u3eCamelina\u3c/i\u3e seeds

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    Seeds of members of the genus Cuphea accumulate medium-chain fatty acids (MCFAs; 8:0ā€“14:0). MCFA- and palmitic acid- (16:0) rich vegetable oils have received attention for jet fuel production, given their similarity in chain length to Jet A fuel hydrocarbons. Studies were conducted to test genes, including those from Cuphea, for their ability to confer jet fuel-type fatty acid accumulation in seed oil of the emerging biofuel crop Camelina sativa. Transcriptomes from Cuphea viscosissima and Cuphea pulcherrima developing seeds that accumulate \u3e90% of C8 and C10 fatty acids revealed three FatB cDNAs (CpuFatB3, CvFatB1, and CpuFatB4) expressed predominantly in seeds and structurally divergent from typical FatB thioesterases that release 16:0 from acyl carrier protein (ACP). Expression of CpuFatB3 and CvFatB1 resulted in Camelina oil with capric acid (10:0), and CpuFatB4 expression conferred myristic acid (14:0) production and increased 16:0. Co-expression of combinations of previously characterized Cuphea and California bay FatBs produced Camelina oils with mixtures of C8ā€“C16 fatty acids, but amounts of each fatty acid were less than obtained by expression of individual FatB cDNAs. Increases in lauric acid (12:0) and 14:0, but not 10:0, in Camelina oil and at the sn-2 position of triacylglycerols resulted from inclusion of a coconut lysophosphatidic acid acyltransferase specialized for MCFAs. RNA interference (RNAi) suppression of Camelina Ī²-ketoacyl-ACP synthase II, however, reduced 12:0 in seeds expressing a 12:0-ACP-specific FatB. Camelina lines presented here provide platforms for additional metabolic engineering targeting fatty acid synthase and specialized acyltransferases for achieving oils with high levels of jet fuel-type fatty acids

    Toward production of jet fuel functionality in oilseeds: identification of FatB acyl-acyl carrier protein thioesterases and evaluation of combinatorial expression strategies in \u3ci\u3eCamelina\u3c/i\u3e seeds

    Get PDF
    Seeds of members of the genus Cuphea accumulate medium-chain fatty acids (MCFAs; 8:0ā€“14:0). MCFA- and palmitic acid- (16:0) rich vegetable oils have received attention for jet fuel production, given their similarity in chain length to Jet A fuel hydrocarbons. Studies were conducted to test genes, including those from Cuphea, for their ability to confer jet fuel-type fatty acid accumulation in seed oil of the emerging biofuel crop Camelina sativa. Transcriptomes from Cuphea viscosissima and Cuphea pulcherrima developing seeds that accumulate \u3e90% of C8 and C10 fatty acids revealed three FatB cDNAs (CpuFatB3, CvFatB1, and CpuFatB4) expressed predominantly in seeds and structurally divergent from typical FatB thioesterases that release 16:0 from acyl carrier protein (ACP). Expression of CpuFatB3 and CvFatB1 resulted in Camelina oil with capric acid (10:0), and CpuFatB4 expression conferred myristic acid (14:0) production and increased 16:0. Co-expression of combinations of previously characterized Cuphea and California bay FatBs produced Camelina oils with mixtures of C8ā€“C16 fatty acids, but amounts of each fatty acid were less than obtained by expression of individual FatB cDNAs. Increases in lauric acid (12:0) and 14:0, but not 10:0, in Camelina oil and at the sn-2 position of triacylglycerols resulted from inclusion of a coconut lysophosphatidic acid acyltransferase specialized for MCFAs. RNA interference (RNAi) suppression of Camelina Ī²-ketoacyl-ACP synthase II, however, reduced 12:0 in seeds expressing a 12:0-ACP-specific FatB. Camelina lines presented here provide platforms for additional metabolic engineering targeting fatty acid synthase and specialized acyltransferases for achieving oils with high levels of jet fuel-type fatty acids

    Toward production of jet fuel functionality in oilseeds: identification of FatB acyl-acyl carrier protein thioesterases and evaluation of combinatorial expression strategies in \u3ci\u3eCamelina\u3c/i\u3e seeds

    Get PDF
    Seeds of members of the genus Cuphea accumulate medium-chain fatty acids (MCFAs; 8:0ā€“14:0). MCFA- and palmitic acid- (16:0) rich vegetable oils have received attention for jet fuel production, given their similarity in chain length to Jet A fuel hydrocarbons. Studies were conducted to test genes, including those from Cuphea, for their ability to confer jet fuel-type fatty acid accumulation in seed oil of the emerging biofuel crop Camelina sativa. Transcriptomes from Cuphea viscosissima and Cuphea pulcherrima developing seeds that accumulate \u3e90% of C8 and C10 fatty acids revealed three FatB cDNAs (CpuFatB3, CvFatB1, and CpuFatB4) expressed predominantly in seeds and structurally divergent from typical FatB thioesterases that release 16:0 from acyl carrier protein (ACP). Expression of CpuFatB3 and CvFatB1 resulted in Camelina oil with capric acid (10:0), and CpuFatB4 expression conferred myristic acid (14:0) production and increased 16:0. Co-expression of combinations of previously characterized Cuphea and California bay FatBs produced Camelina oils with mixtures of C8ā€“C16 fatty acids, but amounts of each fatty acid were less than obtained by expression of individual FatB cDNAs. Increases in lauric acid (12:0) and 14:0, but not 10:0, in Camelina oil and at the sn-2 position of triacylglycerols resulted from inclusion of a coconut lysophosphatidic acid acyltransferase specialized for MCFAs. RNA interference (RNAi) suppression of Camelina Ī²-ketoacyl-ACP synthase II, however, reduced 12:0 in seeds expressing a 12:0-ACP-specific FatB. Camelina lines presented here provide platforms for additional metabolic engineering targeting fatty acid synthase and specialized acyltransferases for achieving oils with high levels of jet fuel-type fatty acids
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