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1.
Stem Cell Res ; 62: 102799, 2022 07.
Article in English | MEDLINE | ID: mdl-35550987

ABSTRACT

Kabuki syndrome (KS) is a rare genetic disorder typically characterized by facial abnormalities, developmental delay, cognitive dysfunction, and organ impairment. In this report, fibroblast cells obtained from a KS patient containing a heterozygous KMT2D c.12592 C>T mutation (p.R4198X) were reprogrammed using non-integrative Sendai virus to generate three induced pluripotent stem cell (iPSC) clones. The iPSC lines retained the KS patient mutation, and displayed normal karyotypes, pluripotency marker expression, and the ability to differentiate into the three germ layers.


Subject(s)
Hematologic Diseases , Induced Pluripotent Stem Cells , Vestibular Diseases , Abnormalities, Multiple , Face/abnormalities , Hematologic Diseases/genetics , Humans , Mutation/genetics , Vestibular Diseases/genetics
2.
mBio ; 13(1): e0344421, 2022 02 22.
Article in English | MEDLINE | ID: mdl-35073756

ABSTRACT

Emerging resistance to artemisinin drugs threatens the elimination of malaria. Resistance is widespread in South East Asia (SEA) and Myanmar. Neighboring Bangladesh, where 90% of infections occur in the Chittagong Hill Tracts (CHTs), lacks recent assessment. We undertook a prospective study in the sole district-level hospital in Bandarban, a CHT district with low population densities but 60% of reported malaria cases. Thirty patients presented with malaria in 2018. An increase to 68 patients in 2019 correlated with the district-level rise in malaria, rainfall, humidity, and temperature. Twenty-four patients (7 in 2018 and 17 in 2019) with uncomplicated Plasmodium falciparum monoinfection were assessed for clearing parasites after starting artemisinin combination therapy (ACT). The median (range) time to clear half of the initial parasites was 5.6 (1.5 to 9.6) h, with 20% of patients showing a median of 8 h. There was no correlation between parasite clearance and initial parasitemia, blood cell counts, or mutations of P. falciparum gene Pfkelch13 (the molecular marker of artemisinin resistance [AR]). The in vitro ring-stage survival assay (RSA) revealed one (of four) culture-adapted strains with a quantifiable resistance of 2.01% ± 0.1% (mean ± standard error of the mean [SEM]). Regression analyses of in vivo and in vitro measurements of the four CHT strains and WHO-validated K13 resistance mutations yielded good correlation (R2 = 0.7; ρ = 0.9, P < 0.005), strengthening evaluation of emerging AR with small sample sizes, a challenge in many low/moderate-prevalence sites. There is an urgent need to deploy multiple, complementary approaches to understand the evolutionary dynamics of the emergence of P. falciparum resistant to artemisinin derivatives in countries where malaria is endemic. IMPORTANCE Malaria elimination is a Millennium Development Goal. Artemisinins, fast-acting antimalarial drugs, have played a key role in malaria elimination. Emergence of artemisinin resistance threatens the global elimination of malaria. Over the last decade, advanced clinical and laboratory methods have documented its spread throughout South East Asia and Myanmar. Neighboring Bangladesh lies in the historical path of dissemination of antimalarial resistance to the rest of the world, yet it has not been evaluated by combinations of leading methods, particularly in the highland Chittagong Hill Tracts adjacent to Myanmar which contain >90% of malaria in Bangladesh. We show the first establishment of capacity to assess clinical artemisinin resistance directly in patients in the hilltops and laboratory adaptation of Bangladeshi parasite strains from a remote, sparsely populated malaria frontier that is responsive to climate. Our study also provides a generalized model for comprehensive monitoring of drug resistance for countries where malaria is endemic.


Subject(s)
Antimalarials , Artemisinins , Drug Resistance , Malaria, Falciparum , Humans , Antimalarials/pharmacology , Artemisinins/therapeutic use , Bangladesh , Drug Resistance/genetics , Malaria, Falciparum/parasitology , Plasmodium falciparum/genetics , Prospective Studies , Protozoan Proteins/genetics
3.
PLoS Comput Biol ; 16(5): e1007871, 2020 05.
Article in English | MEDLINE | ID: mdl-32421718

ABSTRACT

Monogenetic diseases provide unique opportunity for studying complex, clinical states that underlie neurological severity. Loss of glycine decarboxylase (GLDC) can severely impact neurological development as seen in non-ketotic hyperglycinemia (NKH). NKH is a neuro-metabolic disorder lacking quantitative predictors of disease states. It is characterized by elevation of glycine, seizures and failure to thrive, but glycine reduction often fails to confer neurological benefit, suggesting need for alternate tools to distinguish severe from attenuated disease. A major challenge has been that there are 255 unique disease-causing missense mutations in GLDC, of which 206 remain entirely uncharacterized. Here we report a Multiparametric Mutation Score (MMS) developed by combining in silico predictions of stability, evolutionary conservation and protein interaction models and suitable to assess 251 of 255 mutations. In addition, we created a quantitative scale of clinical disease severity comprising of four major disease domains (seizure, cognitive failure, muscular and motor control and brain-malformation) to comprehensively score patient symptoms identified in 131 clinical reports published over the last 15 years. The resulting patient Clinical Outcomes Scores (COS) were used to optimize the MMS for biological and clinical relevance and yield a patient Weighted Multiparametric Mutation Score (WMMS) that separates severe from attenuated neurological disease (p = 1.2 e-5). Our study provides understanding for developing quantitative tools to predict clinical severity of neurological disease and a clinical scale that advances monitoring disease progression needed to evaluate new treatments for NKH.


Subject(s)
Gene Expression Regulation, Enzymologic , Genotype , Glycine Dehydrogenase (Decarboxylating)/genetics , Hyperglycinemia, Nonketotic/genetics , Mutation, Missense , Phenotype , Humans , Hyperglycinemia, Nonketotic/diagnosis , Hyperglycinemia, Nonketotic/pathology , Severity of Illness Index
4.
Front Psychol ; 11: 164, 2020.
Article in English | MEDLINE | ID: mdl-32116958

ABSTRACT

Teachers commonly categorize students as visual or auditory learners. Despite a lack of empirical evidence, teaching to a student's perceived learning style remains common practice in education (Pashler et al., 2009). Having conducted an extensive review of the literature, Pashler et al. (2009) noted, "...very few studies have even used an experimental methodology capable of testing the validity of learning styles applied to education" (p. 105). Rogowsky et al. (2015) published the first study following the experimental design prescribed by Pashler et al. Focusing specifically on the visual/auditory dichotomy, Rogowsky et al. (2015) examined the extent to which learning style predicts comprehension and retention based on mode of instruction. Their study has been noted as "The only study located through the systematic literature search across six different databases and the screening of more than 1000 records that was totally aligned with Pashler's criteria" (Aslaksen and Loras, 2018, p. 3). The caveat to the 2015 study is that it was conducted with adult learners. The current study uses the same design and methodology as its predecessor, but on a school-aged population, making it the first of its kind. Consistent with earlier findings with adults, results failed to find a significant relationship between auditory or visual learning style preference and comprehension. Fifth graders with a visual learning style scored higher than those with an auditory learning style on listening and reading comprehension measures. As such, and counter to current educational beliefs and practices, teachers may actually be doing a disservice to students by using resources to determine their learning style and then tailoring the curriculum to match that learning style.

5.
BMC Med Genet ; 21(1): 42, 2020 02 27.
Article in English | MEDLINE | ID: mdl-32106822

ABSTRACT

BACKGROUND: von Hippel-Lindau (VHL) disease is a familial neoplasia syndrome that results from the germline mutation of VHL. Pathogenic VHL mutations include deletion, frameshift, nonsense and missense mutations. Synonymous mutations are expected to be phenotypically silent and their role in VHL disease remains poorly understood. CASE PRESENTATION: We report a Caucasian male with a family history of pheochromocytoma and the synonymous VHL mutation c.414A > G (p.Pro138Pro). At 47-years, MRI revealed pheochromocytoma in the left adrenal gland and hemangioblastomas in the spine and brain. Pheochromocytoma was treated by adrenalectomy. Radiotherapy, followed by craniotomy and resection were needed to reduce hemangioblastomas to residual lesions. Two of three of the proband's children inherited the mutation and both presented with retinal hemangioblastomas without pheochromocytoma at age 7: one twin needed four laser treatments. Primary skin fibroblasts carrying the heterozygous mutation or wild type VHL were established from the family. Mutant fibroblasts downregulated full-length VHL mRNA and protein, and upregulated the short VHL mRNA isoform (a result of exon 2 skipping in splicing) at the mRNA level but not at the protein level. CONCLUSIONS: Our study shows that the synonymous VHL mutation c.414A > G can within 7 years induce pediatric retinal hemangioblastoma in absence of pheochromocytoma. This highlights the need to include splicing-altering synonymous mutations into the screening for VHL disease. This is also the first report on detecting and validating a synonymous VHL mutation using patient-derived fibroblasts. The mutation c.414A > G translates to p.Pro138Pro, yet it is not functionally silent, because it causes aberrant splicing by skipping exon 2. The reduced but not completely abolished pVHL protein in a loss-of-heterozygosity genetic backdrop may underlie the etiology of VHL disease.


Subject(s)
Cerebellar Neoplasms/genetics , Hemangioblastoma/genetics , RNA Splicing/genetics , Silent Mutation , Von Hippel-Lindau Tumor Suppressor Protein/genetics , Adrenal Gland Neoplasms/complications , Adrenal Gland Neoplasms/diagnosis , Adrenal Gland Neoplasms/genetics , Cerebellar Neoplasms/complications , Cerebellar Neoplasms/diagnosis , Child , Child, Preschool , Family , Female , Frameshift Mutation/genetics , Germ-Line Mutation , Hemangioblastoma/complications , Hemangioblastoma/diagnosis , Humans , Male , Middle Aged , Neoplasms, Multiple Primary/diagnosis , Neoplasms, Multiple Primary/genetics , Pedigree , Pheochromocytoma/complications , Pheochromocytoma/diagnosis , Pheochromocytoma/genetics , Proline/genetics , Retinal Neoplasms/complications , Retinal Neoplasms/diagnosis , Retinal Neoplasms/genetics , Spinal Neoplasms/complications , Spinal Neoplasms/diagnosis , Spinal Neoplasms/genetics , von Hippel-Lindau Disease/complications , von Hippel-Lindau Disease/genetics
6.
Am J Case Rep ; 20: 1159-1169, 2019 Aug 08.
Article in English | MEDLINE | ID: mdl-31391415

ABSTRACT

BACKGROUND Shprintzen-Goldberg syndrome (SGS) is an extremely rare collagenopathy, most often caused by autosomal-dominant mutations in the SKI proto-oncogene, which is a component of the transforming growth factor beta (TGF-ß) signaling pathway. Approximately 50-60 cases of SGS have been recorded in the literature worldwide since its discovery in 1982. This collagen disorder affects bone and vascular development throughout the body, resulting in craniosynostosis, scoliosis, chest deformities, and aortic root dilation. Patients may have problems in the central nervous system, including Chiari 1 malformation, hydrocephalus, and dilation of the lateral ventricles. Unfortunately, the symptoms of SGS closely parallel those of related collagenopathies involving mutations in the TGF-ß signaling pathway, which makes accurate diagnosis difficult without genetic testing, especially in cases with complex presentation. CASE REPORT In this report we present the unique and complex disease manifestations in a 9-year-old girl with SGS. The patient had severe cervical spinal instability that resolved after surgical occipital-C4 fusion with an autograft from the rib. Midface distraction surgery was used to treat the patient's craniosynostosis and related facial deformities. This surgery was complicated by loss of 750 mL of blood due to insufficient dura and prominent vasculature. CONCLUSIONS Connective tissue symptoms associated with SGS can involve dural and vascular problems, as seen in this case report. Thus, the risk of extreme blood loss should be anticipated any time midface distraction surgery is performed on an SGS patient. Continued research is needed to define how this case relates to the SGS patient population.


Subject(s)
Arachnodactyly/surgery , Blood Loss, Surgical , Craniosynostoses/surgery , Dura Mater/abnormalities , Marfan Syndrome/surgery , Osteotomy, Le Fort/adverse effects , Child , Female , Humans , Proto-Oncogene Mas
7.
Games Health J ; 4(2): 145-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-26181808

ABSTRACT

OBJECTIVE: This pilot study aimed to assess whether performance on posturography games correlates with the Gross Motor Function Measure (GMFM) in children with cerebral palsy. MATERIALS AND METHODS: Simple games using static posturography technology allowed subjects to control screen events via postural sway. Game performance was compared with GMFMs using correlation analysis in a convenience sample of nine girls and six boys with cerebral palsy. Likert scales were used to obtain subjective responses to the balance games. RESULTS: GMFM scores correlated with game performance, especially measures emphasizing rhythmic sway. Twelve of the 15 subjects enjoyed the game and asserted an interest in playing again. CONCLUSIONS: Digital posturography games engage children with cerebral palsy in balance tasks, provide visual feedback in a balance control task, and have the potential to increase autonomy in balance control training among pediatric patients with cerebral palsy. This approach can support the relationship between child and therapist. The potential for interactive posturography to complement the assessment and treatment of balance in cerebral palsy bears continuing study.


Subject(s)
Cerebral Palsy/rehabilitation , Exercise Therapy/methods , Motor Skills/physiology , Postural Balance/physiology , User-Computer Interface , Adolescent , Cerebral Palsy/physiopathology , Child , Child, Preschool , Disability Evaluation , Female , Humans , Male , Pilot Projects , Video Games
8.
Exp Brain Res ; 184(4): 493-509, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17896103

ABSTRACT

We investigated the ability of cats to discriminate differences between vowel-like spectra, assessed their discrimination ability over time, and compared spectral receptive fields in primary auditory cortex (AI) of trained and untrained cats. Animals were trained to discriminate changes in the spectral envelope of a broad-band harmonic complex in a 2-alternative forced choice procedure. The standard stimulus was an acoustic grating consisting of a harmonic complex with a sinusoidally modulated spectral envelope ("ripple spectrum"). The spacing of spectral peaks was conserved at 1, 2, or 2.66 peaks/octave. Animals were trained to detect differences in the frequency location of energy peaks, corresponding to changes in the spectral envelope phase. Average discrimination thresholds improved continuously during the course of the testing from phase-shifts of 96 degrees at the beginning to 44 degrees after 4-6 months of training with a 1 ripple/octave spectral envelope. Responses of AI single units and small groups of neurons to pure tones and ripple spectra were modified during perceptual discrimination training with vowel-like ripple stimuli. The transfer function for spectral envelope frequencies narrowed and the tuning for pure tones sharpened significantly in discriminant versus naïve animals. By contrast, control animals that used the ripple spectra only in a lateralization task showed broader ripple transfer functions and narrower pure-tone tuning than naïve animals.


Subject(s)
Auditory Cortex/physiology , Auditory Perception/physiology , Conditioning, Psychological/physiology , Discrimination Learning/physiology , Neuronal Plasticity/physiology , Acoustic Stimulation , Animals , Cats , Electrophysiology , Phonetics , Psychophysics
9.
J Neurophysiol ; 94(6): 4441-54, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16162837

ABSTRACT

The spectral selectivity of auditory nerve fibers was characterized by a method based on responses to random-spectrum-shape stimuli. The method models the average discharge rate of fibers for steady stimuli and is based on responses to approximately 100 noise-like stimuli with pseudorandom spectral levels in 1/8- or 1/16-octave frequency bins. The model assumes that rate is determined by a linear weighting of the spectrum plus a second-order weighting of all pairs of spectrum values within a certain frequency range of best frequency. The method allows prediction of rate responses to stimuli with arbitrary wideband spectral shapes, thus providing a direct test of the degree of linearity of spectral processing Auditory-nerve fibers are shown to rely mainly on linear weighting of the stimulus spectrum; however, significant second-order terms are present and are important in predicting responses to random-spectrum shape stimuli, although not for predicting responses to noise filtered with cat head-related transfer functions. The second-order terms weight the products of levels at identical frequencies positively and the products of different frequencies negatively. As such, they model both curvature in the rate versus level function and suppressive interactions between different frequency components. The first- and second-order characterizations derived in this method provide a measure of higher-order nonlinearities in neurons, albeit without providing information about temporal characteristics.


Subject(s)
Acoustic Stimulation , Auditory Pathways/physiology , Cochlear Nerve/physiology , Evoked Potentials, Auditory/physiology , Models, Neurological , Nonlinear Dynamics , Animals , Cats , Dose-Response Relationship, Radiation , Psychoacoustics , Spectrum Analysis , Time Factors
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