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1.
Gastrointest Endosc ; 99(6): 981-988.e5, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38103750

RESUMEN

BACKGROUND AND AIMS: Jejunostomy tube placements provides enteral access for feeding in eligible patients who cannot meet their nutritional needs by mouth. They can be surgically placed laparoscopically (lap-J) or with the use of a conventional open laparotomy approach (open-J). Recently, direct percutaneous endoscopic jejunostomy (DPEJ) has emerged as an alternative owing to its low cost and shorter recovery times. We sought to retrospectively compare the procedural success rates and adverse events of these methods. METHODS: Patients were identified by querying our health system patient database and the departmental database of patients who underwent DPEJ. The patients were divided into 3 cohorts based on the procedure: DPEJ, lap-J, or open-J. Patient age and body mass index, procedural success rate, and adverse event rate were compared among the 3 groups. RESULTS: A total of 201 patients met inclusion criteria (65 DPEJ, 111 lap-J, and 25 open-J). Procedural success rates were similar among the 3 groups (DPEJ 96.9%, lap-J 99.1%, open-J 100%; P = .702). Rates of infection and bleeding were also similar among the 3 groups. There were no cases of GI perforation. Tube dysfunction for any reason that required complete removal or replacement within 90 days occurred more often in the surgical groups than in the DPEJ group (DPEJ 0%, lap-J 35.1%, open-J 40.0%; P < .001). This was driven largely by increased rates of tube clogging and tube dislodgement in the surgical groups. CONCLUSIONS: DPEJ is a safe and effective alternative to surgical jejunostomy in eligible patients and may be associated with decreased adverse event rates at 90 days.


Asunto(s)
Nutrición Enteral , Yeyunostomía , Humanos , Yeyunostomía/métodos , Yeyunostomía/efectos adversos , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Nutrición Enteral/métodos , Nutrición Enteral/instrumentación , Endoscopía Gastrointestinal/métodos , Endoscopía Gastrointestinal/efectos adversos , Adulto , Laparoscopía/métodos , Resultado del Tratamiento , Anciano de 80 o más Años
2.
Genome ; 59(8): 527-40, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27373142

RESUMEN

In Drosophila melanogaster, the mini-w(+) transgene in Pci is normally expressed throughout the adult eye; however, when other P or KP elements are present, a variegated-eye phenotype results, indicating random w(+) silencing during development called P-element-dependent silencing (PDS). Mutant Su(var)205 and Su(var)3-7 alleles act as haplo-suppressors/triplo-enhancers of this variegated phenotype, indicating that these heterochromatic modifiers act dose dependently in PDS. Previously, we recovered a spontaneous mutation of P{lacW}ci(Dplac) called P{lacW}ci(DplacE1) (E1) that variegated in the absence of P elements, presumably due to the insertion of an adjacent gypsy element. From a screen for genetic modifiers of E1 variegation, we describe here the isolation of five mutations in ash1 and three in trx that enhance the E1 variegated phenotype in a dose-dependent and cumulative manner. These mutant alleles enhance PDS at E1, and in E1/P{lacW}ci(Dplac), but suppress position effect variegation (PEV) at In(1)w(m)(4). This opposite action is consistent with a model where ASH1 and TRX mark transcriptionally active chromatin domains. If ASH1 or TRX function is lost or reduced, heterochromatin can spread into these domains creating a sink that diverts heterochromatic proteins from other variegating locations, which then may express a suppressed phenotype.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Mutación , Factores de Transcripción/genética , Alelos , Animales , Homólogo de la Proteína Chromobox 5 , Drosophila melanogaster/fisiología , Femenino , Silenciador del Gen , Sitios Genéticos , Heterocromatina/genética , Masculino , Fenotipo , Análisis de Secuencia de ADN , Supresión Genética , Transgenes
3.
Neurosurg Rev ; 39(1): 1-11; discussion 11, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26212700

RESUMEN

Expandable vertebral body replacement cages (VBRs) have been widely used for reconstruction of the thoracolumbar spine following corpectomy. However, their use in the cervical spine is less common, and currently, no expandable cages on the market are cleared or approved by the US Food and Drug Administration for use in the cervical spine. The objective of this study was to perform a systematic review on the use of expandable cages in the treatment of cervical spine pathology with a focus on fusion rates, deformity correction, complications, and indications. A comprehensive Medline search was performed, and 24 applicable articles were identified and included in this review. The advantages of expandable cages include greater ease of implantation with less risk of damage to the end plate, less intraoperative manipulation of the device, and potentially greater control over lordosis. They may be particularly advantageous in cases with poor bone quality, such as patients with osteoporosis or metastatic tumors that have been radiated. However, there is a potential risk of overdistraction, which is increased in the cervical spine, their minimum height limits their use in cases with collapsed vertebra, and the amount of hardware in the expansion mechanism may limit the surface area available for fusion. The use of expandable VBRs are a valuable tool in the armamentarium for reconstruction of the anterior column of the cervical spine with an acceptable safety profile. Although expandable cervical cages are clearly beneficial in certain clinical situations, widespread use following all corpectomies is not justified due to their significantly greater cost compared to structural bone grafts or non-expandable VBRs, which can be utilized to achieve similar clinical outcomes.


Asunto(s)
Vértebras Cervicales/cirugía , Cámaras de Difusión de Cultivos , Fijadores Internos , Procedimientos Neuroquirúrgicos/instrumentación , Humanos , Fusión Vertebral
4.
Behav Brain Sci ; 36(5): 495-6; discussion 503-21, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23985414

RESUMEN

Van de Vliert embraces a "supply side" model of human needs, underplaying a "demand" model whereby individuals, motivated by psychological needs, develop coping strategies that help them meet their personal goals and collectively exert an influence on social and economic systems. Undesirable climates may inflate the value of financial capital, but they also boost the value of social capital.


Asunto(s)
Clima , Ecosistema , Libertad , Factores Socioeconómicos , Humanos
5.
Int J Health Care Qual Assur ; 26(7): 653-65, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24167923

RESUMEN

PURPOSE: The purpose of this paper is to gain insight into nurses' understandings of what constitutes suitable footwear for older people in care homes. DESIGN/METHODOLOGY/APPROACH: An exploratory descriptive qualitative survey was carried out of 20 registered nurses employed in six Scottish care homes for older people. Data were collected using a semi-structured questionnaire that included five open-ended questions. Content analysis was used to theme footwear perceptions. FINDINGS: Participants had several views about what encompasses safe footwear; some were erroneous. The link between inappropriate footwear and falls was recognised by 80 per cent of respondents, but some were unclear about the features that effect or inhibit safety. No UK or international standardised guidelines were identified that advise nurses about appropriate footwear for older people. PRACTICAL IMPLICATIONS: It is unknown whether respondents represent the nurse population because findings are restricted by a small sample size. Nonetheless, the group showed variable understanding of what constitutes safe footwear for older people and links with fall prevention. Improved nurse-education about what comprises safe footwear and the links with falls prevention in older people is required. Structured guidelines to direct nurse educators about what to teach student nurses about appropriate footwear for older people may work towards reducing falls. ORIGINALITY/VALUE: No guidelines to direct nurses about appropriate footwear for older people in care homes have been written. Key points have been developed.


Asunto(s)
Accidentes por Caídas/prevención & control , Actitud del Personal de Salud , Hogares para Ancianos/normas , Casas de Salud/normas , Personal de Enfermería/educación , Zapatos/normas , Anciano , Educación Continua en Enfermería , Humanos , Capacitación en Servicio , Personal de Enfermería/normas , Investigación Cualitativa , Recursos Humanos
6.
Chromosoma ; 120(6): 573-85, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22009629

RESUMEN

The P elements of Drosophila melanogaster are well-studied transposons with both mobilizing and repressor functions. P elements can also variably silence the expression of certain other transgenes through a phenomenon known as P element-dependent silencing (PDS). To examine the role of the P repressor in PDS, we have induced, isolated, and characterized 22 point mutations in an archetype P element called P[SalI]89D. All mutations showed a loss in the ability to silence one or more assays for the PDS phenotype. These mutants also lost the ability to induce the suppression of variegation in P[hsp26-pt-T]39C-12, another P element-dependent phenotype. A subgroup of 11 mutations was further assayed for their ability to act as a P repressor and silence the P element promoter transcribing a lacZ ( + ) gene, and this function was lost as well. Taken together, this study supports a model of PDS acting through protein interactions, not RNA, with heterochromatic proteins to modify the extent of variegation seen in PDS. Furthermore, the common loss of functions for PDS and P repressor silencing (from another P promoter) argues for a common role of the repressor. This makes the PDS model a good system for examining P repressor functions and how they relate to transposon-mediated gene silencing in general.


Asunto(s)
Elementos Transponibles de ADN , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Silenciador del Gen , Mutación Puntual , Proteínas Represoras/genética , Animales , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/metabolismo , Proteínas Represoras/metabolismo , Transgenes
7.
J Orthop Res ; 40(4): 909-916, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34081344

RESUMEN

Although bone marrow-derived mesenchymal stem cells (BMCs) have been widely used in spinal fusion procedures, adipose-derived stem cells (ASCs) offer a number of advantages as an alternative clinical cell source. This study directly compares the efficacy of ASCs and BMCs from the same donor animals to achieve successful fusion when combined with a clinical-grade bone graft substitute in a rat lumbar fusion model. ASCs and BMCs were isolated from the same Lewis donor rats and grown to passage 2 (P2). Single-level bilateral posterolateral intertransverse process lumbar fusion surgery was performed on syngeneic rats divided into three experimental groups: clinical-grade bone graft substitute alone (CBGS); CBGS+ rat ASCs (rASC); and, CBGS+ rat BMCs (rBMC). Eight weeks postoperatively, fusion was evaluated via micro-CT, manual palpation and histology. In vitro analysis of the osteogenic capacity of rBMCs and rASCs was also performed. Results indicated that the average fusion volume in the rASC group was the largest and was significantly larger than the CBGS group. Although the rASC group displayed the highest fusion rates via micro-CT and manual palpation, this difference was not statistically significant. Cell-seeded grafts showed more histological bone formation than cell-free grafts. P2 rASCs and rBMCs displayed similar in vitro osteogenic differentiation capacities. Overall, this study showed that, when combined with a clinical-grade bone graft substitute in a rat model, rASCs cells yielded the largest fusion masses and comparable fusion results to rBMCs. These results add to growing evidence that ASCs provide an attractive alternative to BMCs for spinal fusion procedures.


Asunto(s)
Sustitutos de Huesos , Fusión Vertebral , Animales , Médula Ósea , Vértebras Lumbares/cirugía , Osteogénesis , Ratas , Ratas Endogámicas Lew , Fusión Vertebral/métodos
8.
Endosc Int Open ; 10(9): E1282-E1290, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36118633

RESUMEN

Background and study aims Obesity prevalence continues to rise in the United States with Roux-en-Y gastric bypass (RYGB) surgery being one of the most common bariatric procedures. With this trend, more patients with altered upper gastrointestinal (UGI) anatomy have required endoscopic intervention including direct percutaneous endoscopic jejunostomy (DPEJ) placement. We aimed to assess the safety and success rates of DPEJ in RYGB patients. Patients and methods All patients at a tertiary care referral center who underwent DPEJ during an 8-year period were queried from a prospectively maintained registry of all enteroscopy procedures. Duplicate cases and altered upper UGI anatomy subtypes other than RYGB were excluded. The final cohort consisted of two groups: RYGB vs native anatomy (NA). Demographic, procedural, readmission, follow-up, and complication data were recorded. Comparative analysis was performed. Results Seventy-two patients were included where 28 had RYGB and 44 had NA. Both groups had similar baseline and pre-procedure data. Procedure success rate was 89 % in RYGB patients and 98 % in NA patients ( P  = 0.13). There were no intraprocedural complications. Early and late postprocedural complication rates were similar between the groups (both 4 % vs 7 %). Average follow-up times in the RYGB and NA groups were 12.97 ±â€Š9.35 and 13.44 ±â€Š9.21 months, respectively. Although readmission rates at 1 and 6 months were higher in the NA versus the RYGB group (21 % vs 7 % and 25 % vs 15 %), these differences were not significant. Conclusions DPEJ can be successful and safely placed in RYGB patients with no significant difference in procedure success, complication, or readmission rates when compared to control.

9.
J Cell Biol ; 174(3): 349-58, 2006 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-16880270

RESUMEN

In mammalian cells, the GW182 protein localizes to cytoplasmic bodies implicated in the regulation of messenger RNA (mRNA) stability, translation, and the RNA interference pathway. Many of these functions have also been assigned to analogous yeast cytoplasmic mRNA processing bodies. We have characterized the single Drosophila melanogaster homologue of the human GW182 protein family, which we have named Gawky (GW). Drosophila GW localizes to punctate, cytoplasmic foci in an RNA-dependent manner. Drosophila GW bodies (GWBs) appear to function analogously to human GWBs, as human GW182 colocalizes with GW when expressed in Drosophila cells. The RNA-induced silencing complex component Argonaute2 and orthologues of LSm4 and Xrn1 (Pacman) associated with 5'-3' mRNA degradation localize to some GWBs. Reducing GW activity by mutation or antibody injection during syncytial embryo development leads to abnormal nuclear divisions, demonstrating an early requirement for GWB-mediated cytoplasmic mRNA regulation. This suggests that gw represents a previously unknown member of a small group of genes that need to be expressed zygotically during early embryo development.


Asunto(s)
Estructuras Citoplasmáticas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriología , ARN Mensajero/metabolismo , Animales , Anticuerpos/inmunología , División del Núcleo Celular , Segregación Cromosómica , Estructuras Citoplasmáticas/ultraestructura , Proteínas de Drosophila/química , Proteínas de Drosophila/deficiencia , Drosophila melanogaster/citología , Drosophila melanogaster/ultraestructura , Embrión no Mamífero/citología , Embrión no Mamífero/embriología , Embrión no Mamífero/ultraestructura , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Humanos , Mutación/genética , Filogenia , Transporte de Proteínas , Cigoto/citología , Cigoto/ultraestructura
10.
Genome ; 54(9): 752-62, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21888571

RESUMEN

Transposable elements are found in the genomes of all eukaryotes and play a critical role in altering gene expression and genome organization. In Drosophila melanogaster, transposable P elements are responsible for the phenomenon of hybrid dysgenesis. KP elements, a deletion-derivative of the complete P element, can suppress this mutagenic effect. KP elements can also silence the expression of certain other P-element-mediated transgenes in a process called P-element-dependent silencing (PDS), which is thought to involve the recruitment of heterochromatin proteins. To explore the mechanism of this silencing, we have mobilized KP elements to create a series of strains that contain single, well-defined KP insertions that show PDS. To understand the quantitative role of KP elements in PDS, these single inserts were combined in a series of crosses to obtain genotypes with zero, one, or two KP elements, from which we could examine the effect of KP gene dose. The extent of PDS in these genotypes was shown to be dose dependent in a logarithmic rather than linear fashion. A logarithmic dose dependency is consistent with the KP products interacting with heterochromatic proteins in a concentration-dependent manner such that two molecules are needed to induce gene silencing.


Asunto(s)
Variaciones en el Número de Copia de ADN/genética , Elementos Transponibles de ADN/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas Nucleares/genética , Proteínas de Unión al ARN/genética , Animales , Secuencia de Bases , Proteínas de Drosophila/metabolismo , Color del Ojo/genética , Dosificación de Gen , Regulación de la Expresión Génica , Silenciador del Gen , Genotipo , Heterocromatina/metabolismo , Proteínas Nucleares/metabolismo , Epitelio Pigmentado Ocular/metabolismo , Proteínas de Unión al ARN/metabolismo , Análisis de Secuencia de ADN , Eliminación de Secuencia , Elementos Silenciadores Transcripcionales/genética
11.
Front Psychol ; 12: 651108, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33935911

RESUMEN

Many studies of primate vocalization have been undertaken to improve our understanding of the evolution of language. Perhaps, for this reason, investigators have focused on calls that were thought to carry symbolic information about the environment. Here I suggest that even if these calls were in fact symbolic, there were independent reasons to question this approach in the first place. I begin by asking what kind of communication system would satisfy a species' biological needs. For example, where animals benefit from living in large groups, I ask how members would need to communicate to keep their groups from fragmenting. In this context, I discuss the role of social grooming and "close calls," including lip-smacking and grunting. Parallels exist in human societies, where information is exchanged about all kinds of things, often less about the nominal topic than the communicants themselves. This sort of indexical (or personal) information is vital to group living, which presupposes the ability to tolerate, relate to, and interact constructively with other individuals. Making indexical communication the focus of comparative research encourages consideration of somatic and behavioral cues that facilitate relationships and social benefits, including cooperation and collaboration. There is ample room here for a different and potentially more fruitful approach to communication in humans and other primates, one that focuses on personal appraisals, based on cues originating with individuals, rather than signals excited by environmental events.

12.
J Orthop Surg Res ; 15(1): 410, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32933551

RESUMEN

BACKGROUND: Despite widespread use of femoral-sourced allografts in clinical spinal fusion procedures and the increasing interest in using femoral reamer-irrigator-aspirator (RIA) autograft in clinical bone grafting, few studies have examined the efficacy of femoral grafts compared to iliac crest grafts in spinal fusion. The objective of this study was to directly compare the use of autologous iliac crest with syngeneic femoral and iliac allograft bone in the rat model of lumbar spinal fusion. METHODS: Single-level bilateral posterolateral intertransverse process lumbar spinal fusion surgery was performed on Lewis rats divided into three experimental groups: iliac crest autograft, syngeneic iliac crest allograft, and syngeneic femoral allograft bone. Eight weeks postoperatively, fusion was evaluated via microCT analysis, manual palpation, and histology. In vitro analysis of the colony-forming and osteogenic capacity of bone marrow cells derived from rat femurs and hips was also performed to determine whether there was a correlation with the fusion efficacy of these graft sources. RESULTS: Although no differences were observed between groups in CT fusion mass volumes, iliac allografts displayed an increased number of radiographically fused fusion masses and a higher rate of bilateral fusion via manual palpation. Histologically, hip-derived grafts showed better integration with host bone than femur derived ones, likely associated with the higher concentration of osteogenic progenitor cells observed in hip-derived bone marrow. CONCLUSIONS: This study demonstrates the feasibility of using syngeneic allograft bone in place of autograft bone within inbred rat fusion models and highlights the need for further study of femoral-derived grafts in fusion.


Asunto(s)
Aloinjertos , Autoinjertos , Trasplante Óseo/métodos , Fémur/trasplante , Ilion/trasplante , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Animales , Células de la Médula Ósea/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Estudios de Factibilidad , Femenino , Vértebras Lumbares/diagnóstico por imagen , Osteogénesis , Ratas Endogámicas Lew , Células Madre , Tomografía Computarizada por Rayos X
13.
J Bone Joint Surg Am ; 101(19): 1741-1749, 2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31577679

RESUMEN

BACKGROUND: Local, intrawound use of antibiotic powder, such as vancomycin and tobramycin, in spinal fusion surgery has become an increasingly common prophylactic measure in an attempt to reduce rates of postsurgical infection. However, the effects of localized antibiotic delivery on fusion remain unclear. The objective of this study was to examine the in vivo effects of intraoperative local delivery of 2 antibiotics commonly used in bone-grafting surgery on spinal fusion outcomes in a rat model. METHODS: Single-level (L4-L5), bilateral posterolateral intertransverse process lumbar fusion surgery was performed on 60 female Lewis rats (6 to 8 weeks of age) using syngeneic iliac crest allograft mixed with clinical bone-graft substitute and varying concentrations of antibiotics (n = 12 each): (1) control without any antibiotics, (2) low-dose vancomycin (14.3 mg/kg), (3) high-dose vancomycin (71.5 mg/kg), (4) low-dose tobramycin (28.6 mg/kg), and (5) high-dose tobramycin (143 mg/kg). Eight weeks postoperatively, fusion was evaluated via micro-computed tomography (µCT), manual palpation, and histological analysis, with blinding to treatment group. In the µCT analysis, fusion-mass volumes were measured for each rat. Each spine specimen (L4-L5) was rated (manual palpation score) on a scale of 2 to 0 (2 = fused, 1 = partially fused, and 0 = non-fused). RESULTS: The mean fusion-mass volume on µCT (mm) was as follows: control, 29.3 ± 6.2; low-dose vancomycin, 26.3 ± 8.9; high-dose vancomycin, 18.8 ± 7.9; low-dose tobramycin, 32.7 ± 9.0; and high-dose tobramycin, 43.8 ± 11.9 (control versus high-dose vancomycin, p < 0.05; and control versus high-dose tobramycin, p < 0.05). The mean manual palpation score for each group was as follows: control, 1.46 ± 0.58; low-dose vancomycin, 0.86 ± 0.87; high-dose vancomycin, 0.68 ± 0.62; low-dose tobramycin, 1.25 ± 0.71; and high-dose tobramycin, 1.32 ± 0.72 (control versus high-dose vancomycin, p < 0.05). The histological analyses demonstrated a similar trend with regard to spinal fusion volume. CONCLUSIONS: Intraoperative local application of vancomycin, particularly at a supraphysiological dosage, may have detrimental effects on fusion-mass formation. No inhibitory effect of tobramycin on fusion-mass formation was observed. CLINICAL RELEVANCE: When spine surgeons decide to use intraoperative intrawound antibiotics in spinal fusion surgery, they should weigh the reduction in surgical site infection against a possible inhibitory effect on fusion.


Asunto(s)
Antibacterianos/administración & dosificación , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Tobramicina/administración & dosificación , Vancomicina/administración & dosificación , Animales , Relación Dosis-Respuesta a Droga , Humanos , Vértebras Lumbares/diagnóstico por imagen , Osteoblastos/patología , Palpación/métodos , Polvos , Ratas Endogámicas Lew , Infección de la Herida Quirúrgica/patología , Infección de la Herida Quirúrgica/prevención & control , Microtomografía por Rayos X
14.
J Theor Biol ; 251(4): 640-52, 2008 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-18291421

RESUMEN

The handicap principle has been applied to a number of different traits in the last three decades, but it is difficult to characterize its record, or even its perceived relevance, when it comes to an important human attribute-spoken language. In some cases, assumptions regarding the energetic cost of speech, and the veracity of linguistically encoded messages, have failed to recognize critical aspects of human development, cognition, and social ecology. In other cases, the fact that speech contains honest (physiological) information, and tends to be used honestly with family and friends, has been overlooked. Speech and language are functionally related but they involve different resources. Individuals can increase the attractiveness of their speech, and of more stylized vocal and verbal performances, without enhancing linguistic structure or content; and they can modify their use of language without significant changes in the physical form of speech. That its production costs are normally low enables speech to be produced extravagantly in bids for status and mating relationships, and in evolution, may have allowed its content--linguistic knowledge and structure--to become complex.


Asunto(s)
Lenguaje , Selección Genética , Habla/fisiología , Cognición , Comunicación , Humanos , Medio Social , Conducta Verbal
15.
J Speech Lang Hear Res ; 51(5): 1300-14, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18812490

RESUMEN

PURPOSE: This study examined the development of timing characteristics in early spontaneous speech of children who were later identified as having reading disability (RD). METHOD: Child-adult play sessions were recorded longitudinally at 2 and 3 years of age in 27 children, most of whom were at high familial risk for RD. For each speaking turn, the number of syllables was determined and an acoustic analysis measured the time allocated to articulation, pausing before speaking, and pausing during speaking. RESULTS: In grade school, a reading battery identified 9 children with RD and 18 children without RD (9 at high risk, 9 at low risk). Early speaking rate was significantly slower in the group with RD, with significantly different patterns of pausing compared with children without RD. Group differences became more distinct by age 3, as longer speaking turns were attempted. CONCLUSIONS: The results are discussed in terms of speech and language formulation. Phonetic plans may be shorter and/or less specified in children with RD, surfacing as slow, short speaking turns with increased pausing relative to articulation. This explanation is consistent with several accounts of RD and provides a perspective on how speech and language deficits may manifest during spontaneous verbal interactions between young children and adults.


Asunto(s)
Dislexia/fisiopatología , Habla/fisiología , Conducta Verbal/fisiología , Preescolar , Dislexia/epidemiología , Femenino , Humanos , Pruebas del Lenguaje , Estudios Longitudinales , Masculino , Tiempo de Reacción/fisiología , Lectura , Factores de Riesgo , Acústica del Lenguaje , Inteligibilidad del Habla
16.
Read Writ ; 31(1): 75-98, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29367806

RESUMEN

A randomized control trial compared the effects of two kinds of vocabulary instruction on component reading skills of adult struggling readers. Participants seeking alternative high school diplomas received 8 h of scripted tutoring to learn forty academic vocabulary words embedded within a civics curriculum. They were matched for language background and reading levels, then randomly assigned to either morpho-phonemic analysis teaching word origins, morpheme and syllable structures, or traditional whole word study teaching multiple sentence contexts, meaningful connections, and spellings. Both groups made comparable gains in learning the target words, but the morpho-phonemic group showed greater gains in reading unfamiliar words on standardized tests of word reading, including word attack and word recognition. Findings support theories of word learning and literacy that promote explicit instruction in word analysis to increase poor readers' linguistic awareness by revealing connections between morphological, phonological, and orthographic structures within words.

17.
World Neurosurg ; 115: e366-e374, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29678698

RESUMEN

BACKGROUND: Parathyroid hormone (PTH) (1-34) treatment reduces fracture risk in osteoporotic patients. Previously, we demonstrated in a rabbit model that low-dose PTH treatment resulted in increased fusion mass volume. As effects of PTH on bone are dose-dependent, we aimed to evaluate whether increasing dosage of PTH increases both volume and biomechanical stiffness of the resulting fusion masses and/or exhibits synergistic effects with low-dose bone morphogenetic protein 2 (BMP-2). METHODS: Posterolateral lumbar spinal fusion surgery was performed on 60 New Zealand White rabbits divided into 6 experimental groups: iliac crest autograft alone, autograft plus 20 µg/kg/day PTH, autograft plus 40 µg/kg/day PTH, BMP-2 alone, BMP-2 plus 20 µg/kg/day PTH, and BMP-2 plus 40 µg/kg PTH. Fusion was assessed at postoperative week 6 via manual palpation, volumetric computed tomography analysis, and 4-point bending biomechanical testing. RESULTS: All groups treated with BMP-2 fused. Increasing doses of PTH resulted in increased fusion mass volume compared with autograft alone. Autograft plus 40 µg/kg/day PTH yielded fusion mass volumes comparable to BMP-2. When the autograft groups were considered alone, increased mechanical stiffness was observed only in the 20 µg/kg/day group. No significant stiffness differences were observed between BMP-2 groups. CONCLUSIONS: Treatment with the highest dose of PTH resulted in fusion mass volumes similar to those obtained with BMP-2. When the autograft groups were considered alone, significant increases in mechanical stiffness were observed at a dosage of 20 µg/kg/day, suggesting there may be an optimal dose of PTH in the rabbit model. Effects of BMP-2 on fusion were dominant.


Asunto(s)
Proteína Morfogenética Ósea 2/farmacología , Ilion/trasplante , Vértebras Lumbares/cirugía , Hormona Paratiroidea/farmacología , Animales , Proteínas Morfogenéticas Óseas/uso terapéutico , Trasplante Óseo/métodos , Ilion/efectos de los fármacos , Vértebras Lumbares/efectos de los fármacos , Región Lumbosacra/diagnóstico por imagen , Masculino , Modelos Animales , Conejos , Fusión Vertebral/métodos , Trasplante Autólogo/métodos
18.
Psychon Bull Rev ; 24(1): 232-237, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27432002

RESUMEN

Although language is generally spoken, most evolutionary proposals say little about any changes that may have induced vocal control. Here I suggest that the interaction of two changes in our species-one in sociality, the other in life history-liberated the voice from its affective moorings, enabling it to serve as a fitness cue or signal. The modification of life history increased the helplessness of infants, thus their competition for care, pressuring them to emit, and parents (and others) to evaluate, new vocal cues in bids for attention. This change elaborated and formalized the care communication system that was used in infancy and, because of parental adoption of social criteria, extended it into childhood, supporting the extrafamilial relationships that intensify in those stages. The remodeling of life history, in conjunction with intensified sociality, also enhanced vocal signaling in adolescence-a second stage that is unique to humans-and adulthood. Building on the new vocal skills and fitness criteria that emerged earlier, I claim that males with ornamented speech enjoyed advantages in their pursuit of dominance and reproductive opportunities in evolutionary history, as they do today. There are implications of this scenario for the mechanistic level of vocal diversification. Today, intentionality plays a role both in the instrumental crying of infants and the modulated vocalizations of adults. In evolutionary history, I claim that in both cases, spontaneously emitted behavioral cues elicited perceptible responses, giving rise to strategic signals that were sent, and processed, under a new and fundamentally different neural regime.


Asunto(s)
Evolución Biológica , Conducta Verbal , Voz , Humanos
19.
Genetics ; 170(1): 5-6, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15781711

RESUMEN

Although mitosis and meiosis are fundamental to understanding genetics, students often find them difficult to learn. We suggest using common "pool noodles" as teaching aids to represent chromatids in classroom demonstrations. Students use these noodles to demonstrate the processes of synapsis, segregation, and recombination. Student feedback has been overwhelmingly positive.


Asunto(s)
Cromosomas/genética , Citogenética/educación , Meiosis/genética , Mitosis/genética , Modelos Genéticos
20.
Genetics ; 170(1): 127-38, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15466427

RESUMEN

For more than 80 years, the euchromatic right arm of the Drosophila fourth chromosome (101F-102F) has been one of the least genetically accessible regions of the fly genome despite the fact that many important genes reside there. To improve the mapping of genes on the fourth chromosome, we describe a strategy to generate targeted deficiencies and we describe 13 deficiencies that subdivide the 300 kb between the cytological coordinates 102A6 and 102C1 into five discrete regions plus a 200-kb region from 102C1 to 102D6. Together these deficiencies substantially improve the mapping capabilities for mutant loci on the fourth chromosome.


Asunto(s)
Aberraciones Cromosómicas , Mapeo Cromosómico , Drosophila melanogaster/genética , Mutagénesis Sitio-Dirigida , Animales , Genes Letales , Marcadores Genéticos
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