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Benedek G, Edvardson S, Alon SA, Galun E, Lako R, Rivkin M, Riek LP, Ramadhan Lasu AA, Levite M, Miller K, Abed El Latif M
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PLoS Negl Trop Dis,
2020]
Nodding syndrome (NS) is a devastating and enigmatic childhood epilepsy. NS is accompanied by multiple neurological impairments and neuroinflammation, and associated with the parasite Onchocerca volvulus (Ov) and other environmental factors. Moreover, NS seems to be an 'Autoimmune Epilepsy' since: 1. ~50% of NS patients have neurotoxic cross-reactive Ov/Leimodin-I autoimmune antibodies. 2. Our recently-published findings: Most (~86%) of NS patients have glutamate-receptor AMPA-GluR3B-peptide autoimmune-antibodies that bind, induce Reactive-Oxygen-Species, and kill both neural cells and T cells. Furthermore, NS patient's IgG induce seizures, brain multiple damage alike occurring in brains of NS patients, and elevation of T cells and activated microglia and astrocytes, in brains of normal mice. Human Leukocyte antigen (HLA) class I and II molecules are critical for initiating effective beneficial immunity against foreign microorganisms and contributing to proper brain function, but also predispose to detrimental autoimmunity against self-peptides. We analyzed seven HLA loci, either by next-generation-sequencing or Sequence-Specific-Oligonucleotide-Probe, in 48 NS patients and 51 healthy controls from South Sudan. We discovered that NS associates significantly with both protective HLA haplotype: HLA-B*42:01, C*17:01, DRB1*03:02, DQB1*04:02 and DQA1*04:01, and susceptible motif: Ala24, Glu63 and Phe67, in the HLA-B peptide-binding groove. These amino acids create a hydrophobic and sterically closed peptide-binding HLA pocket, favoring proline residue. Our findings suggest that immunogenetic fingerprints in HLA peptide-binding grooves tentatively associate with protection or susceptibility to NS. Accordingly, different HLA molecules may explain why under similar environmental factors, only some children, within the same families, tribes and districts, develop NS, while others do not.
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Int J Pharm,
2020]
In this work, the increase of the Caenorhabditis elegans (C.elegans) lifespan extension using hyper-branched cyclodextrin-based nanosponges (CD-NS) complexing oxyresveratrol (OXY), and the possible inhibition of C.elegans phosphodiesterase type 4 (PDE4) were evaluated. The titration displacement of fluorescein was used to calculate the apparent complexation constant (K<sub>F</sub>) between CD-NS and OXY. Moreover, PDE4 was expressed in E.coli, purified and refolded in presence of cyclodextrins (CDs) to study its possible inhibition as pharmacological target of OXY. The apparent activity was characterized and the inhibitory effect of OXY on PDE4 displayed a competitive in vitro inhibition corroborated in silico. A maximum increase of the in vivo life expectancy of about 9.6% of using OXY/CD-NS complexes in comparison with the control was obtained, in contrast to the 6.5 % obtained with free OXY. No effect on lifespan or toxicity with CD-NS alone was found. These results as a whole represent new opportunities to use OXY and CD-NS in lifespan products.
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Pan Afr Med J,
2017]
Nodding Syndrome (NS) is a childhood neurological disorder characterized by atonic seizures, cognitive decline, school dropout, muscle weakness, thermal dysfunction, wasting and stunted growth. There are recent published information suggesting associations between Nodding Syndrome (NS) with cerebrospinal fluid (CSF) VGKC antibodies and serum leiomidin-1 antibody cross reacting with Onchocerca Volvulus (OV). These findings suggest a neuro-inflammatory cause of NS and they are important findings in the search for the cause of Nodding Syndrome. These observations perhaps provide further, the unique explanation for the association between Nodding Syndrome and Onchocerca Volvulus. Many clinical and epidemiological studies had shown a significant correlation between NS and infestation with a nematode, Onchocerca volvulus which causes a disease, Onchocerciasis, some of which when left untreated can develop visual defect ("River Blindness"). While these studies conducted in Northern Uganda and Southern Sudan indicate a statistically significant association with (OV infection (using positive skin snips), we observe that (OV is generally endemic in many parts of Sub Saharan Africa and Latin America and that to date, no NS cases have been recorded in those regions. This letter to the Editor is to provide additional information on the current view about the relationship between Nodding Syndrome and Onchocerca Volvulus as seen in Northern Uganda.
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Int J Pharm,
2023]
In this study, the ability of zein nanospheres (NS) and zein nanocapsules containing wheat germ oil (NC) to enhance the bioavailability and efficacy of quercetin was evaluated. Both types of nanocarriers had similar physico-chemical properties, including size (between 230 and 250 nm), spherical shape, negative zeta potential, and surface hydrophobicity. However, NS displayed a higher ability than NC to interact with the intestinal epithelium, as evidenced by an oral biodistribution study in rats. Moreover, both types of nanocarriers offered similar loading efficiencies and release profiles in simulated fluids. In C. elegans, the encapsulation of quercetin in nanospheres (Q-NS) was found to be two twice more effective than the free form of quercetin in reducing lipid accumulation. For nanocapsules, the presence of wheat germ oil significantly increased the storage of lipids in C. elegans; although the incorporation of quercetin (Q-NC) significantly counteracted the presence of the oil. Finally, nanoparticles improved the oral absorption of quercetin in Wistar rats, offering a relative oral bioavailability of 26% and 57% for Q-NS and Q-NC, respectively, compared to a 5% for the control formulation. Overall, the study suggests that zein nanocarriers, particularly nanospheres, could be useful in improving the bioavailability and efficacy of quercetin.
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[
Parasitol Today,
1996]
Spliced leader trans-splicing is a form of RNA processing originally described and studied in parasitic kinetoplastida. This mechanism of gene expression also occurs in parasitic and free-living metazoa. In this review, Dick Davis describes current knowledge of the distribution, substrates, specificity and functional significance of trans-splicing in metazoa.
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International Worm Meeting,
2015]
STEM professionals in the 21st century remain predominantly Caucasian/white, in spite of decades of work by professional societies, colleges and universities, and individual scientists to broaden participation. This multifaceted problem includes concerns among students and faculty at minority-serving institutions about the economics of career choice, family pressure to pursue a career in a biomedical field, and limited exposure to natural history. Further, institutional efforts in recruitment by research universities remain rooted in graduate fairs that target senior undergraduates from groups underrepresented in science, whereas connections made via shared research networks provide a more sure means to admission in molecular and cell biology. The UC Davis-University of Maryland Eastern Shore (UMES) Molecular and Cellular Biology Graduate Admissions Pathways (MCBGAP) program addresses this challenge via collaborations between faculty at the two institutions and a research co-mentoring program that brings UMES undergraduates to UC Davis for summer research. The program is funded by a grant from the University of California Office of the President and the UC Davis College of Biological Sciences.MCBGAP supported two cohorts of five UMES students in the summers of 2014 and 2015. The MCBGAP program consists of reciprocal student-faculty visits, close interactions between key UC Davis and UMES faculty, monthly Skype meetings that involve mentors and students, and research, professional development, and field trips in the summer. MCBGAP has catalyzed change both at UMES, where students are given the opportunity to self-identify as researchers at a tier 1 research university, and at UC Davis, where increased numbers of faculty recognize the need to be proactive in graduate recruiting and admissions, and multiple deans have committed time to mentor students and funds to support additional undergraduates from Historically Black Colleges and Universities for summer research and mentoring. The experience has also inspired us to apply for a Postbaccalaureate Research Education Program (PREP) from the NIH.
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Opt Express,
2008]
Nanosecond laser pulses (lambda = 355 nm) were used to cut mechanosensory neurons in Caenorhabditis elegans and motorneurons in Drosophila melanogaster larvae. A pulse energy range of 0.8-1.2 microJ and < 20 pulses in single shot mode were sufficient to generate axonal cuts. Viability post-surgery was >95% for C. elegans and 60% for Drosophila. Cavitation bubble dynamics generated due to laser-induced plasma formation were observed in vivo by time-resolved imaging in both organisms. Bubble oscillations were severely damped in vivo and cavitation dynamics were complete within 100 ns in C. elegans and 800 ns in Drosophila. We report the use of this system to study axonal transport for the first time and discuss advantages of nanosecond lasers compared to femtosecond sources for such procedures.
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Eur J Hum Genet,
2003]
Noonan syndrome (NS, MIM 163950) is an autosomal dominant condition characterised by facial dysmorphy, congenital cardiac defects and short stature. Recently missense mutations in PTPN11, the gene encoding the nonreceptor protein tyrosine phosphatase SHP-2 on 12q24, were identified in 50% of analysed Noonan cases. A large four-generation Belgian family with NS and some features suggestive of cardio-facio-cutaneous syndrome (CFC) was previously used to fine map the Noonan syndrome candidate region to a 5 cM region in 12q24. We now report the identification of a mutation (Gln79Arg) in the PTPN11 gene in this large family. In D. melanogaster and C. elegans the PTPN11 gene has been implicated in oogenesis. In this family two affected females had dizygous twins. This suggests that PTPN11 might also be involved in oogenesis and twinning in humans.European Journal of Human Genetics (2002) 11, 85-88. doi:10.1038/sj.ejhg.5200915
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Infect Immun,
2013]
Acinetobacter baumannii has become a major problem in the clinical setting with the prevalence of infections caused by multidrug-resistant strains on the increase. Nevertheless, only a limited number of molecular mechanisms involved in the success of A. baumannii as a human pathogen have been described. In this study, we examined the virulence features of a hypermotile derivative of A. baumannii strain ATCC 17978, which was found to display enhanced adherence to human pneumocytes and elevated levels of lethality toward Caenorhabditis elegans nematodes. Analysis of cellular lipids revealed modifications to the fatty acid composition, providing a possible explanation for the observed changes in hydrophobicity and subsequent alteration in adherence and motility. Comparison of the genome sequences of the hypermotile variant and parental strain revealed that an insertion sequence had disrupted an hns-like gene in the variant. This gene encodes a homologue of the histone-like nucleoid structuring (H-NS) protein, a known global transcriptional repressor. Transcriptome analysis identified the global effects of this mutation on gene expression, with major changes seen in the autotransporter Ata, a type VI secretion system, and a type I pilus cluster. Interestingly, isolation and analysis of a second independent hypermotile ATCC 17978 variant revealed a mutation to a residue within the DNA binding region of H-NS. Taken together, these mutants indicate that the phenotypic and transcriptomic differences seen are due to loss of regulatory control effected by H-NS.
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[
Neuronal Development, Synaptic Function and Behavior, Madison, WI,
2010]
Over fortyAscaris FMRFamide-like (AF) peptides have been sequenced in the parasiticnematode Ascaris suum by the Strettonlab. Many of these peptides have beenshown to have potent effects on the A.suum locomotory nervous system (Davis & Stretton, 1996). Locomotion isvital to the survival of the parasite in its host so an in-depth knowledge ofpeptide localization and behavioral effects is essential to develop neweffective anthelmintics. The FMRFamide-like peptide AF19 (AEGLSSPLIRFamide)has been shown to have inhibitory effects on locomotion (Davis & Stretton,2001). Injection of the peptide in the head-restricted behavioral assayabolished all locomotory waveforms and their propagations (Reinitz &Stretton, 2000). Ananti-peptide antibody specific to AF19 reproducibly stains a subset of neuronsin the cephalic region of A. suum. ALA , one of the two cells in the dorsal ganglion , shows AF19-immunoreactivity. This isdata is corroborated by single cell mass spectrometric (MS) and MS/MS data. Cloning, based on th sequence ofa novel peptide in ALA, yieldedthe transcript that encodes AF19 (
afp-13)and two other amidated peptides. In situ hybridizationexperiments are planned to further corroborate the cellular localization ofAF19. Supported by NIH grant AI15429.