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1.
J Speech Lang Hear Res ; 67(3): 974-988, 2024 03 11.
Article in English | MEDLINE | ID: mdl-38354099

ABSTRACT

PURPOSE: Developmental dyslexia is proposed to involve selective procedural memory deficits with intact declarative memory. Recent research in the domain of category learning has demonstrated that adults with dyslexia have selective deficits in Information-Integration (II) category learning that is proposed to rely on procedural learning mechanisms and unaffected Rule-Based (RB) category learning that is proposed to rely on declarative, hypothesis testing mechanisms. Importantly, learning mechanisms also change across development, with distinct developmental trajectories in both procedural and declarative learning mechanisms. It is unclear how dyslexia in childhood should influence auditory category learning, a critical skill for speech perception and reading development. METHOD: We examined auditory category learning performance and strategies in 7- to 12-year-old children with dyslexia (n = 25; nine females, 16 males) and typically developing controls (n = 25; 13 females, 12 males). Participants learned nonspeech auditory categories of spectrotemporal ripples that could be optimally learned with either RB selective attention to the temporal modulation dimension or procedural integration of information across spectral and temporal dimensions. We statistically compared performance using mixed-model analyses of variance and identified strategies using decision-bound computational models. RESULTS: We found that children with dyslexia have an apparent selective RB category learning deficit, rather than a selective II learning deficit observed in prior work in adults with dyslexia. CONCLUSION: These results suggest that the important skill of auditory category learning is impacted in children with dyslexia and throughout development, individuals with dyslexia may develop compensatory strategies that preserve declarative learning while developing difficulties in procedural learning. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25148519.


Subject(s)
Dyslexia , Speech Perception , Male , Adult , Child , Female , Humans , Learning , Reading , Research Design , Auditory Perception
2.
Cell Biol Int ; 45(10): 2074-2085, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34189808

ABSTRACT

This study evaluated such as exposure to ethinylestradiol during the prenatal (18th-22nd day) and pubertal (42nd-49th day) periods acts on the male ventral prostate and female prostate of 12-month old gerbils. We performed the analysis to serum hormone levels for estradiol and testosterone. The prostates were submitted to morphometric and immunohistochemical analyses. Exposure to ethinylestradiol during these developmental periods decreased the testosterone serum levels in males and increased the estradiol serum levels in females. Morphologically, prostate intraepithelial neoplasia and disorders in the arrangement of the fibrous components were observed in the prostate glands of both sexes of gerbil exposed to ethinylestradiol during development periods. In the male prostate, the ethinylestradiol promoted decreased in the frequency of positive epithelial cell for androgen receptor (AR) and increased the frequency of positive stromal cell for estrogen receptor α. However, in the female prostate, this synthetic estrogen caused AR upregulation and increased cell proliferation. This study shows that the exposure to ethinylestradiol during development phases alters the morphology and the hormonal signaling in the male and female prostates of old gerbils, confirming the action of ethinylestradiol as endocrine disruptor.


Subject(s)
Epithelial Cells/cytology , Ethinyl Estradiol/pharmacology , Prenatal Exposure Delayed Effects/pathology , Prostate/anatomy & histology , Animals , Animals, Newborn , Cell Proliferation , Epithelial Cells/drug effects , Estrogens/pharmacology , Ethinyl Estradiol/administration & dosage , Ethinyl Estradiol/toxicity , Female , Gerbillinae , Male , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , Prostate/drug effects
3.
J Pediatr ; 236: 54-61.e1, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34004191

ABSTRACT

OBJECTIVE: To demonstrate that a novel noninvasive index of intracranial pressure (ICP) derived from diffuse optics-based techniques is associated with intracranial hypertension. STUDY DESIGN: We compared noninvasive and invasive ICP measurements in infants with hydrocephalus. Infants born term and preterm were eligible for inclusion if clinically determined to require cerebrospinal fluid (CSF) diversion. Ventricular size was assessed preoperatively via ultrasound measurement of the fronto-occipital (FOR) and frontotemporal (FTHR) horn ratios. Invasive ICP was obtained at the time of surgical intervention with a manometer. Intracranial hypertension was defined as invasive ICP ≥15 mmHg. Diffuse optical measurements of cerebral perfusion, oxygen extraction, and noninvasive ICP were performed preoperatively, intraoperatively, and postoperatively. Optical and ultrasound measures were compared with invasive ICP measurements, and their change in values after CSF diversion were obtained. RESULTS: We included 39 infants, 23 with intracranial hypertension. No group difference in ventricular size was found by FOR (P = .93) or FTHR (P = .76). Infants with intracranial hypertension had significantly higher noninvasive ICP (P = .02) and oxygen extraction fraction (OEF) (P = .01) compared with infants without intracranial hypertension. Increased cerebral blood flow (P = .005) and improved OEF (P < .001) after CSF diversion were observed only in infants with intracranial hypertension. CONCLUSIONS: Noninvasive diffuse optical measures (including a noninvasive ICP index) were associated with intracranial hypertension. The findings suggest that impaired perfusion from intracranial hypertension was independent of ventricular size. Hemodynamic evidence of the benefits of CSF diversion was seen in infants with intracranial hypertension. Noninvasive optical techniques hold promise for aiding the assessment of CSF diversion timing.


Subject(s)
Cerebrovascular Circulation/physiology , Hydrocephalus/diagnostic imaging , Hydrocephalus/physiopathology , Intracranial Hypertension/diagnosis , Cerebrospinal Fluid Shunts , Feasibility Studies , Female , Humans , Hydrocephalus/surgery , Infant, Newborn , Intracranial Hypertension/etiology , Intracranial Hypertension/physiopathology , Intracranial Pressure/physiology , Male , Optical Imaging , Pilot Projects , Reproducibility of Results , Spectrum Analysis
4.
Spine (Phila Pa 1976) ; 45(13): E781-E786, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32539291

ABSTRACT

STUDY DESIGN: This is a level IV retrospective descriptive study at a single institution. OBJECTIVE: The objective of the study was to determine the preoperative signs or symptoms prompting cervicomedullary imaging in Jeune syndrome. SUMMARY OF BACKGROUND DATA: Jeune syndrome is a rare autosomal recessive disorder that results in pulmonary compromise from abnormal development of the thorax. Multiple medical comorbidities complicate timely diagnosis of cervicomedullary stenosis, which neurologically jeopardizes this patient population with regards to improper cervical manipulation. Currently, explicit screening of the cervicomedullary junction is not advocated in national guidelines. METHODS: The User Reporting Workbench and Center for Thoracic Insufficiency Syndrome (CTIS) Safety Registry was queried for patients with Jeune syndrome under the age of 18 with cervicomedullary stenosis with or without suboccipital craniectomy/craniotomy evaluated at the authors' institution from January 1, 2007 to August 21, 2018. The primary outcome was the clinical reason for cervicomedullary screening. Secondary outcomes were: age at time of surgery, preoperative myelopathy (spasticity, urinary retention), hydrocephalus, postoperative deficits (respiratory, motor, swallowing difficulty), and need for cervical fusion. RESULTS: Of 32 patients with Jeune syndrome, four (12.5%) had cervicomedullary stenosis requiring decompression. The average age at surgery was 5.25 months (2-9 mo). Two patients underwent imaging due to desaturation events while the other two patients were diagnosed with cervical stenosis as an incidental finding. No patients exhibited clinical myelopathy. Two patients had baseline preoperative swallowing difficulties. None of the patients postoperatively required cervical fusions, nor did they exhibit respiratory deficits, motor deficits, or worsening swallowing difficulties. CONCLUSION: Jeune patients should be routinely screened for cervicomedullary stenosis and undergo subsequent prophylactic decompression to minimize or eliminate the development of irreversible neurologic compromise. LEVEL OF EVIDENCE: 4.


Subject(s)
Decompression, Surgical , Ellis-Van Creveld Syndrome/complications , Ellis-Van Creveld Syndrome/surgery , Nerve Compression Syndromes/prevention & control , Spinal Stenosis/surgery , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Deglutition Disorders/etiology , Humans , Hydrocephalus/etiology , Infant , Nerve Compression Syndromes/etiology , Neurosurgical Procedures , Postoperative Period , Retrospective Studies , Spinal Cord , Spinal Stenosis/diagnostic imaging , Spinal Stenosis/etiology , Spinal Stenosis/prevention & control
5.
Health Aff (Millwood) ; 37(3): 421-428, 2018 03.
Article in English | MEDLINE | ID: mdl-29505365

ABSTRACT

The quality of breast cancer care among Medicare beneficiaries in the US territories-where federal spending for health care is lower than in the continental US-is unknown. We compared female Medicare beneficiaries who were residents of the US territories and had surgical treatment for breast cancer in 2008-14 to those in the continental US in terms of receipt of recommended breast cancer care (diagnostic needle biopsy and adjuvant radiation therapy [RT] following breast-conserving surgery) and the timeliness (time from needle biopsy to surgery and from surgery to adjuvant RT) of that care. Residents of the US territories were less likely to receive recommended care (24 percent lower odds of receiving diagnostic needle biopsy and 34 percent lower odds of receiving adjuvant RT) and to receive timely care (45 percent lower odds of receiving surgery and 82 percent lower odds of receiving adjuvant RT, both within three months). Further research is needed to identify barriers to the provision of adequate and timely breast cancer care in this unique population.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/radiotherapy , Breast Neoplasms/surgery , Healthcare Disparities , Medicare/statistics & numerical data , Quality of Health Care , Aged , Aged, 80 and over , Female , Humans , Insurance Claim Review/statistics & numerical data , Puerto Rico , Retrospective Studies , Time Factors , United States
6.
Mol Ecol ; 23(10): 2543-58, 2014 May.
Article in English | MEDLINE | ID: mdl-24703227

ABSTRACT

Soil heterogeneity is an important driver of divergent natural selection in plants. Neotropical forests have the highest tree diversity on earth, and frequently, soil specialist congeners are distributed parapatrically. While the role of edaphic heterogeneity in the origin and maintenance of tropical tree diversity is unknown, it has been posited that natural selection across the patchwork of soils in the Amazon rainforest is important in driving and maintaining tree diversity. We examined genetic and morphological differentiation among populations of the tropical tree Protium subserratum growing parapatrically on the mosaic of white-sand, brown-sand and clay soils found throughout western Amazonia. Nuclear microsatellites and leaf morphology were used to (i) quantify the extent of phenotypic and genetic divergence across habitat types, (ii) assess the importance of natural selection vs. drift in population divergence, (iii) determine the extent of hybridization and introgression across habitat types, (iv) estimate migration rates among populations. We found significant morphological variation correlated with soil type. Higher levels of genetic differentiation and lower migration rates were observed between adjacent populations found on different soil types than between geographically distant populations on the same soil type. PST -FST comparisons indicate a role for natural selection in population divergence among soil types. A small number of hybrids were detected suggesting that gene flow among soil specialist populations may occur at low frequencies. Our results suggest that edaphic specialization has occurred multiple times in P. subserratum and that divergent natural selection across edaphic boundaries may be a general mechanism promoting and maintaining Amazonian tree diversity.


Subject(s)
Burseraceae/genetics , Ecosystem , Genetics, Population , Selection, Genetic , Soil , Bayes Theorem , Cluster Analysis , Ecotype , Gene Flow , Genetic Drift , Hybridization, Genetic , Linkage Disequilibrium , Microsatellite Repeats , Peru , Phenotype , Plant Leaves/anatomy & histology , Trees/genetics
7.
PLoS One ; 8(5): e62639, 2013.
Article in English | MEDLINE | ID: mdl-23667502

ABSTRACT

The formation of spatial genetic structure (SGS) may originate from different patterns of seed deposition in the landscape, and is mostly determined by seed dispersal limitation. After dispersal, mechanisms such as filtering by environmental factors or attack by herbivores/pathogens throughout plant development stages, and potentially either disrupt or intensify SGS patterns. We investigated how the genotype of Protium subserratum (Burseraceae), a common tree species in the Ducke Reserve, Brazil, is distributed across the landscape. We used seven microsatellite markers to assess the SGS among plants at different life stages and in different environments. By quantifying the patterns of relatedness among plants of different sizes, we inferred the ontogenetic stage in which SGS changes occurred, and compared these effects across soil types. Relatedness among seedlings decreased when distance between seedlings increased, especially for the youngest seedlings. However, this trend was not continued by older plants, as relatedness values were higher among neighboring individuals of the juvenile and adult size class. Contrasting relatedness patterns between seedlings and larger individuals suggests a trade-off between the negative effects of being near closely-related adults (e.g. due to herbivore and pathogen attack) and the advantage of being in a site favorable to establishment. We also found that soil texture strongly influenced density-dependence patterns, as young seedlings in clay soils were more related to each other than were seedlings in bottomland sandy soils, suggesting that the mechanisms that create and maintain patterns of SGS within a population may interact with environmental heterogeneity.


Subject(s)
Burseraceae/growth & development , Burseraceae/genetics , Genotype , Phylogeny , Soil/chemistry , Spatial Analysis , Ecosystem , Genetic Variation , Seedlings/genetics , Seedlings/growth & development
8.
Arch Latinoam Nutr ; 37(1): 122-31, 1987 Mar.
Article in Spanish | MEDLINE | ID: mdl-3454612

ABSTRACT

Trial were conducted in Costa Rica in 1984 and 1985, to determine the possibility of substituting pejibaye (Bactris gasipaes H.B.K.) meal for wheat flour in bread. Utilization in three distinct mixtures was examined: 90:10, 85:15 and 80:20 percentage of wheat flour to percentage of pejibaye meal, respectively. The breads were made, and dough analyses were conducted at "Molinos de Costa Rica, S.A.", the country's principal flour mill. Chemical analyses were carried out at the University of Costa Rica. Results indicate a marked inverse relationship between both initial dough development time and dough strength maintenance, and the content of pejibaye meal present in the flour mixture. Consequent problems with sufficient dough expansion preclude utilization of this fruit meal for bread-making in proportions significantly greater than 10% of the total composite flour. The above-mentioned findings reflect the high nutritional value of the pejibaye fruit. Although the protein content is inversely correlated with the amount of pejibaye meal in the mixture, vitamin A and fat contents are positively correlated. This fact demonstrates that the utilization of pejibaye meal in bread-making may well be in some ways considered as a form of nutritional enrichment. As a final conclusion drawn from the results of analyses of the trials and sensory observations, the 90% wheat flour with 10% pejibaye meal mixture apparently was the optimum substitution level of the breads examined. The potential macroeconomic ramifications on the Costa Rican economy of producing and utilizing pejibaye meal in bread-making, are highly favorable.


Subject(s)
Bread , Flour , Food Handling , Fruit , Fruit/analysis , Nutritive Value
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