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1.
Brain ; 146(3): 968-976, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36181424

ABSTRACT

The aetiology of nodding syndrome remains unclear, and comprehensive genotyping and phenotyping data from patients remain sparse. Our objectives were to characterize the phenotype of patients with nodding syndrome, investigate potential contributors to disease aetiology, and evaluate response to immunotherapy. This cohort study investigated members of a single-family unit from Lamwo District, Uganda. The participants for this study were selected by the Ugandan Ministry of Health as representative for nodding syndrome and with a conducive family structure for genomic analyses. Of the eight family members who participated in the study at the National Institutes of Health (NIH) Clinical Center, three had nodding syndrome. The three affected patients were extensively evaluated with metagenomic sequencing for infectious pathogens, exome sequencing, spinal fluid immune analyses, neurometabolic and toxicology testing, continuous electroencephalography and neuroimaging. Five unaffected family members underwent a subset of testing for comparison. A distinctive interictal pattern of sleep-activated bursts of generalized and multifocal epileptiform discharges and slowing was observed in two patients. Brain imaging showed two patients had mild generalized cerebral atrophy, and both patients and unaffected family members had excessive metal deposition in the basal ganglia. Trace metal biochemical evaluation was normal. CSF was non-inflammatory and one patient had CSF-restricted oligoclonal bands. Onchocerca volvulus-specific antibodies were present in all patients and skin snips were negative for active onchocerciasis. Metagenomic sequencing of serum and CSF revealed hepatitis B virus in the serum of one patient. Vitamin B6 metabolites were borderline low in all family members and CSF pyridoxine metabolites were normal. Mitochondrial DNA testing was normal. Exome sequencing did not identify potentially causal candidate gene variants. Nodding syndrome is characterized by a distinctive pattern of sleep-activated epileptiform activity. The associated growth stunting may be due to hypothalamic dysfunction. Extensive testing years after disease onset did not clarify a causal aetiology. A trial of immunomodulation (plasmapheresis in two patients and intravenous immunoglobulin in one patient) was given without short-term effect, but longer-term follow-up was not possible to fully assess any benefit of this intervention.


Subject(s)
Nodding Syndrome , Onchocerciasis , United States , Humans , Cohort Studies , Immunomodulation , Genomics
2.
Bioorg Med Chem Lett ; 30(16): 127358, 2020 08 15.
Article in English | MEDLINE | ID: mdl-32631554

ABSTRACT

Thionation of adatanserin hydrochloride (2) with Lawesson's reagent in toluene/triethylamine afforded novel compound, (3r,5r,7r)-N-(2-(4-(pyrimidin-2-yl)piperazin-1-yl)ethyl)adamantane-1-carbothioamide (thioadatanserin, 3) in 84-90% isolated yield. Thioadatanserin underwent a tandem double alkylation with methyl iodide and benzyl bromide in NaH/THF to produce novel dialkylated products 6 and 7 respectively. The single X-ray crystal structure of 7 was determined to be 1-(2-((E- ((3r,5r,7r)-adamantan-1-yl)benzylthio)methylene)amino)ethyl)-1-benzyl-4- (pyrimidin-2-yl)piperazin-1-ium bromide showing that the piperazine ring adopts a chair-like configuration that is not co-planar with the pyrimidine ring. Thioadatanserin emerged as a dual potent partial agonist with activity against 5-HTR1A (EC50 6.7 nM) and antagonist activity against 5-HTR2A (IC50 62.3 nM) and was selective over 5-HTR2C receptor (IC50 > 3333 nM) in the PathHunter® ß-arrestin assays.


Subject(s)
Anxiety Disorders/drug therapy , Depression/drug therapy , Receptor, Serotonin, 5-HT1A/metabolism , Receptor, Serotonin, 5-HT2A/metabolism , Serotonin 5-HT1 Receptor Agonists/pharmacology , Serotonin 5-HT2 Receptor Antagonists/pharmacology , Alkylation , Dose-Response Relationship, Drug , Humans , Molecular Structure , Serotonin 5-HT1 Receptor Agonists/chemical synthesis , Serotonin 5-HT1 Receptor Agonists/chemistry , Serotonin 5-HT2 Receptor Antagonists/chemical synthesis , Serotonin 5-HT2 Receptor Antagonists/chemistry , Structure-Activity Relationship
3.
Proc Natl Acad Sci U S A ; 111(14): 5331-6, 2014 Apr 08.
Article in English | MEDLINE | ID: mdl-24706848

ABSTRACT

Hypoxia-driven changes in the tumor microenvironment facilitate cancer metastasis. In the present study, we investigated the regulatory cross talk between endocytic pathway, hypoxia, and tumor metastasis. Dynamin 2 (DNM2), a GTPase, is a critical mediator of endocytosis. Hypoxia decreased the levels of DNM2. DNM2 promoter has multiple hypoxia-inducible factor (HIF)-binding sites and genetic deletion of them relieved hypoxia-induced transcriptional suppression. Interestingly, DNM2 reciprocally regulated HIF. Inhibition of DNM2 GTPase activity and dominant-negative mutant of DNM2 showed a functional role for DNM2 in regulating HIF. Furthermore, the opposite strand of DNM2 gene encodes miR-199a, which is similarly reduced in cancer cells under hypoxia. miR-199a targets the 3'-UTR of HIF-1α and HIF-2α. Decreased miR-199a expression in hypoxia increased HIF levels. Exogenous expression of miR-199a decreased HIF, cell migration, and metastasis of ovarian cancer cells. miR-199a-mediated changes in HIF levels affected expression of the matrix-remodeling enzyme, lysyloxidase (LOX). LOX levels negatively correlated with progression-free survival in ovarian cancer patients. These results demonstrate a regulatory relationship between DNM2, miR-199a, and HIF, with implications in cancer metastasis.


Subject(s)
Dynamin II/physiology , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , MicroRNAs/physiology , Neoplasm Metastasis , Ovarian Neoplasms/pathology , Down-Regulation , Extracellular Matrix/metabolism , Female , Humans , Lipoxygenase/metabolism , MicroRNAs/genetics , Ovarian Neoplasms/genetics , Ovarian Neoplasms/metabolism , Peritoneal Neoplasms/secondary
4.
Ecotoxicol Environ Saf ; 142: 544-554, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28482323

ABSTRACT

Bioassays of planarian neoplasia highlight the potential of these organisms as useful standards to assess whether environmental toxins such as cadmium promote tumorigenesis. These studies complement other investigations into the exceptional healing and regeneration of planarians - processes that are driven by a population of active stem cells, or neoblasts, which are likely transformed during planarian tumor growth. Our goal was to determine if planarian tumorigenesis assays are amenable to mechanistic studies of cadmium carcinogenesis. To that end we demonstrate, by examining both counts of cell populations by size, and instances of mitosis, that the activity of the stem cell population can be monitored. We also provide evidence that specific biomodulators can affect the potential of planarian neoplastic growth, in that an inhibitor of metalloproteinases effectively blocked the development of the lesions. From these results, we infer that neoblast activity does respond to cadmium-induced tumor growth, and that metalloproteinases are required for the progression of cancer in the planarian.


Subject(s)
Cadmium/toxicity , Carcinogens/toxicity , Cell Transformation, Neoplastic/chemically induced , Models, Biological , Planarians/drug effects , Animals , Benchmarking , Carcinogenicity Tests , Cell Transformation, Neoplastic/ultrastructure , Cocarcinogenesis , Mitosis/drug effects , Planarians/cytology , Regeneration/drug effects
5.
J Med Entomol ; 57(1): 131-155, 2020 01 09.
Article in English | MEDLINE | ID: mdl-31368492

ABSTRACT

In the United States, tick-borne diseases are increasing in incidence and cases are reported over an expanding geographical area. Avoiding tick bites is a key strategy in tick-borne disease prevention, and this requires current and accurate information on where humans are at risk for exposure to ticks. Based on a review of published literature and records in the U.S. National Tick Collection and National Ecological Observatory Network databases, we compiled an updated county-level map showing the reported distribution of the American dog tick, Dermacentor variabilis (Say). We show that this vector of the bacterial agents causing Rocky Mountain spotted fever and tularemia is widely distributed, with records derived from 45 states across the contiguous United States. However, within these states, county-level records of established tick populations are limited. Relative to the range of suitable habitat for this tick, our data imply that D. variabilis is currently underreported in the peer-reviewed literature, highlighting a need for improved surveillance and documentation of existing tick records.


Subject(s)
Animal Distribution , Dermacentor , Animals , United States
6.
Transl Res ; 215: 31-40, 2020 01.
Article in English | MEDLINE | ID: mdl-31520587

ABSTRACT

Precision medicine has generated diagnoses for many patients with challenging undiagnosed disorders. Some individuals remain without a diagnosis despite comprehensive testing, and this impedes their treatment. This report addresses the role of personalized medicine in identifying effective therapy for an undiagnosed disease. A 22-year-old woman presented with chronic severe recurrent trismus, facial pain, progressive multicentric inflammatory and fibrotic masses, and high C-reactive protein. Sites of disease included the pterygomaxillary region, masseter muscles, mandible, lung, pericardium, intrabdominal cavity, and retroperitoneum. A diagnosis was not established after an extensive assessment, including multiple biopsies. The patient was subsequently evaluated under the Undiagnosed Diseases Program at the National Institutes of Health. Large scale genotyping, proteomic studies, and in vitro and gene expression analyses of fibroblasts obtained from a major disease locus were performed. Germline genetic testing did not identify strong candidate genes; proteomic studies of the patient's serum and bronchoalveolar lavage fluid and gene expression analyses of her cells were consistent with dysregulation of the tumor necrosis factor-alpha pathway. The patient's cultured fibroblasts were incubated with selected drugs, and cell proliferation was inhibited by hydroxychloroquine. Treatment of the patient with hydroxychloroquine conferred prolonged beneficial clinical effects, including stabilization of trismus and reduction of corticosteroid dose, C-reactive protein, and size of masses. This case represents an example of precision medicine applied to discover effective treatments for individuals with enigmatic undiagnosed disorders.


Subject(s)
Disease Progression , Inflammation/diagnosis , Inflammation/therapy , Interdisciplinary Research , Precision Medicine , Undiagnosed Diseases/therapy , Adolescent , Bronchoalveolar Lavage Fluid , Female , Fibroblasts/pathology , Fibrosis , Gene Expression Regulation , Humans , Hydroxychloroquine/therapeutic use , Inflammation/diagnostic imaging , Inflammation/genetics , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Treatment Outcome , Undiagnosed Diseases/blood , Undiagnosed Diseases/diagnostic imaging , Undiagnosed Diseases/genetics , Young Adult
7.
Proc Natl Acad Sci U S A ; 103(23): 8607-12, 2006 Jun 06.
Article in English | MEDLINE | ID: mdl-16731626

ABSTRACT

There is growing evidence that dissolved phosphorus can regulate planktonic production in the oceans' subtropical gyres, yet there is little quantitative information about the biochemical fate of phosphorus in planktonic communities. We observed in the North Pacific Subtropical Gyre (NPSG) that the synthesis of membrane lipids accounted for 18-28% of the phosphate (PO4(3-)) taken up by the total planktonic community. Paradoxically, Prochlorococcus, the cyanobacterium that dominates NPSG phytoplankton, primarily synthesizes sulfoquinovosyldiacylglycerol (SQDG), a lipid that contains sulfur and sugar instead of phosphate. In axenic cultures of Prochlorococcus, it was observed that <1% of the total PO4(3-) uptake was incorporated into membrane lipids. Liquid chromatography/mass spectrometry of planktonic lipids in the NPSG confirmed that SQDG was the dominant membrane lipid. Furthermore, the analyses of SQDG synthesis genes from the Sargasso Sea environmental genome showed that the use of sulfolipids in subtropical gyres was confined primarily to picocyanobacteria; no sequences related to known heterotrophic bacterial SQDG lineages were found. This biochemical adaptation by Prochlorococcus must be a significant benefit to these organisms, which compete against phospholipid-rich heterotrophic bacteria for PO4(3-). Thus, evolution of this "sulfur-for-phosphorus" strategy set the stage for the success of picocyanobacteria in oligotrophic environments and may have been a major event in Earth's early history when the relative availability of sulfate and PO4(3-) were significantly different from today's ocean.


Subject(s)
Environment , Lipids/pharmacology , Phosphorus/metabolism , Prochlorococcus/drug effects , Prochlorococcus/metabolism , Seawater/microbiology , Chromatography, High Pressure Liquid , Genome, Bacterial/genetics , Membrane Lipids/chemistry , Phylogeny , Plankton/chemistry , Plankton/metabolism , Prochlorococcus/genetics
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