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1.
Nat Commun ; 15(1): 3108, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600080

RESUMEN

The senescence of fruit is a complex physiological process, with various cell types within the pericarp, making it highly challenging to elucidate their individual roles in fruit senescence. In this study, a single-cell expression atlas of the pericarp of pitaya (Hylocereus undatus) is constructed, revealing exocarp and mesocarp cells undergoing the most significant changes during the fruit senescence process. Pseudotime analysis establishes cellular differentiation and gene expression trajectories during senescence. Early-stage oxidative stress imbalance is followed by the activation of resistance in exocarp cells, subsequently senescence-associated proteins accumulate in the mesocarp cells at late-stage senescence. The central role of the early response factor HuCMB1 is unveiled in the senescence regulatory network. This study provides a spatiotemporal perspective for a deeper understanding of the dynamic senescence process in plants.


Asunto(s)
Cactaceae , Frutas , Frutas/genética , Proteínas/genética , Cactaceae/genética , Análisis de Secuencia de ARN
2.
Hortic Res ; 10(5): uhad058, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37213680

RESUMEN

Recent advances in genome sequencing and assembly techniques have made it possible to achieve chromosome level reference genomes for citrus. Relatively few genomes have been anchored at the chromosome level and/or are haplotype phased, with the available genomes of varying accuracy and completeness. We now report a phased high-quality chromosome level genome assembly for an Australian native citrus species; Citrus australis (round lime) using highly accurate PacBio HiFi long reads, complemented with Hi-C scaffolding. Hifiasm with Hi-C integrated assembly resulted in a 331 Mb genome of C. australis with two haplotypes of nine pseudochromosomes with an N50 of 36.3 Mb and 98.8% genome assembly completeness (BUSCO). Repeat analysis showed that more than 50% of the genome contained interspersed repeats. Among them, LTR elements were the predominant type (21.0%), of which LTR Gypsy (9.8%) and LTR copia (7.7%) elements were the most abundant repeats. A total of 29 464 genes and 32 009 transcripts were identified in the genome. Of these, 28 222 CDS (25 753 genes) had BLAST hits and 21 401 CDS (75.8%) were annotated with at least one GO term. Citrus specific genes for antimicrobial peptides, defense, volatile compounds and acidity regulation were identified. The synteny analysis showed conserved regions between the two haplotypes with some structural variations in Chromosomes 2, 4, 7 and 8. This chromosome scale, and haplotype resolved C. australis genome will facilitate the study of important genes for citrus breeding and will also allow the enhanced definition of the evolutionary relationships between wild and domesticated citrus species.

3.
BMC Genomics ; 24(1): 18, 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36639618

RESUMEN

BACKGROUND: The importance of uridine 5'-diphosphate glucose (UDP-G) synthesis and degradation on carbon (C) partitioning has been indicated in several studies of plant systems, whereby the kinetic properties and abundance of involved enzymes had a significant effect upon the volume of C moving into the hemicellulose, cellulose and sucrose pools. In this study, the expression of 136 genes belonging to 32 gene families related to UDP-G metabolism was studied in 3 major sugarcane organs (including leaf, internode and root) at 6 different developmental stages in 2 commercial genotypes. RESULTS: Analysis of the genes associated with UDP-G metabolism in leaves indicated low expression of sucrose synthase, but relatively high expression of invertase genes, specifically cell-wall invertase 4 and neutral acid invertase 1-1 and 3 genes. Further, organs that are primarily responsible for sucrose synthesis or bioaccumulation, i.e., in source organs (mature leaves) and storage sink organs (mature internodes), had very low expression of sucrose, cellulose and hemicellulose synthesis genes, specifically sucrose synthase 1 and 2, UDP-G dehydrogenase 5 and several cellulose synthase subunit genes. Gene expression was mostly very low in both leaf and mature internode samples; however, leaves did have a comparatively heightened invertase and sucrose phosphate synthase expression. Major differences were observed in the transcription of several genes between immature sink organs (roots and immature internodes). Gene transcription favoured utilisation of UDP-G toward insoluble and respiratory pools in roots. Whereas, there was comparatively higher expression of sucrose synthetic genes, sucrose phosphate synthase 1 and 4, and comparatively lower expression of many genes associated with C flow to insoluble and respiratory pools including myo-Inositol oxygenase, UDP-G dehydrogenase 4, vacuolar invertase 1, and several cell-wall invertases in immature internodes. CONCLUSION: This study represents the first effort to quantify the expression of gene families associated with UDP-G metabolism in sugarcane. Transcriptional analysis displayed the likelihood that C partitioning in sugarcane is closely related to the transcription of genes associated with the UDP-G metabolism. The data presented may provide an accurate genetic reference for future efforts in altering UDP-G metabolism and in turn C partitioning in sugarcane.


Asunto(s)
Saccharum , Saccharum/metabolismo , beta-Fructofuranosidasa/genética , beta-Fructofuranosidasa/metabolismo , Uridina Difosfato/metabolismo , Sacarosa/metabolismo , Celulosa/metabolismo , Glucosa/metabolismo , Oxidorreductasas/metabolismo
4.
Biotechnol Biofuels ; 13(1): 201, 2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33298135

RESUMEN

BACKGROUND: The composition of biomass determines its suitability for different applications within a biorefinery system. The proportion of the major biomass fractions (sugar, cellulose, hemicellulose and lignin) may vary in different sugarcane genotypes and growth environments and different parts of the plant. This study investigated the composition of mature and immature internodes, roots and mature leaves of sugarcane. RESULTS: Internodes were found to have a significantly larger alcohol-soluble component than leaves and roots. The primary difference between the immature and mature internodes was the ratio of soluble sugars. In mature tissues, sucrose content was significantly higher, whereas in immature internodal tissues there was lower sucrose and heightened concentrations of reducing sugars. Carbon (C) partitioning in leaf tissues was characterised by low levels of soluble components and high "other" and cell wall fractions. Root tissue had low ratios of soluble fractions relative to their cell wall contents, indicating a lack of storage of soluble carbon. There was no significant difference in the ratio of the major cell wall fractions between the major organ types. Characterisation of individual non-cellulosic monomers indicated leaf and root tissues had significantly higher arabinose and galactose fractions. Significantly larger proportions of syringyl lignin compounds and the hydroxycinnamic compound, p-coumaric acid were observed in mature internodal tissues compared to the other tissue types. Tissue-specific differences in composition were shown to greatly affect the recalcitrance of the cell wall to enzymatic saccharification. CONCLUSIONS: Overall, this study displayed clear evidence of the differential partitioning of C throughout the sugarcane plant in specific organs. These organ-specific differences have major implications in their utility as a bioproduct feedstock. For example, the inclusion of trash (leaves) with the culms (internodes) may alter processing efficiency.

5.
BMC Plant Biol ; 19(1): 160, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-31023213

RESUMEN

BACKGROUND: Sugarcane accumulates very high levels of sucrose in the culm. Elucidation of the molecular mechanisms that allows such high sucrose synthesis and accumulation (up to 650 mM) is made difficult by the complexity of the highly polyploid genome. Here we report the use of RNA Seq data to characterize the sucrose synthase (SuSy) genes expressed in the transcriptome of the mature sugarcane plant. RESULTS: Four SuSy gene families were identified in the sugarcane Iso-Seq long read transcriptome (SUGIT) through gene annotation of transcripts that mapped to reference SuSy genes from sorghum and maize. In total, 38, 19, 14, and 2 transcripts were identified for the four corresponding SuSy genes 1, 2, 4 and 7, respectively. Comparative studies using available SuSy genes from sorghum (1, 2, 4, 6, 7) and maize (1-7) revealed that the sugarcane SuSy genes were interrupted by multiple introns and that they share a highly conserved gene structure. Spatial expression of the four SuSy genes in sugarcane genotypes and in the progenitor species, Saccharum spontaneum and Saccharum officinarum, was studied in the leaf and root tissues and also in three regions of the culm tissue; top, middle and bottom internodes. Expression profiles indicated that all SuSy transcripts were differentially expressed between the top and bottom tissues, with high expression in the top tissues, lower expression in the bottom and moderate expression in the middle, indicating a gradient of SuSy activity in the sugarcane culm. Further, the root tissue had similar expression levels to that of the top internodes while leaf tissues showed lower expression. In the progenitors, SuSy7 was found to be highly expressed in S. officinarum while the other three SuSy genes had moderate expression in both the progenitors. CONCLUSIONS: The high expression of the SuSy genes in sink tissues, the top internodes and the roots suggests functional roles in sucrose utilization to support growth. The SuSy7 gene has not been previously reported in sugarcane. As sugarcane is unique in storing such high amounts of sucrose, it is possible that there are more SuSy genes/isoforms with specific expression patterns to be discovered in this complex system.


Asunto(s)
Genes de Plantas , Variación Genética , Glucosiltransferasas/genética , Especificidad de Órganos/genética , Saccharum/genética , Transcriptoma/genética , Exones/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Intrones/genética , Sistemas de Lectura Abierta/genética , Oryza/genética , Filogenia , Sorghum/genética , Zea mays/genética
6.
BMC Genomics ; 18(1): 395, 2017 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-28532419

RESUMEN

BACKGROUND: Despite the economic importance of sugarcane in sugar and bioenergy production, there is not yet a reference genome available. Most of the sugarcane transcriptomic studies have been based on Saccharum officinarum gene indices (SoGI), expressed sequence tags (ESTs) and de novo assembled transcript contigs from short-reads; hence knowledge of the sugarcane transcriptome is limited in relation to transcript length and number of transcript isoforms. RESULTS: The sugarcane transcriptome was sequenced using PacBio isoform sequencing (Iso-Seq) of a pooled RNA sample derived from leaf, internode and root tissues, of different developmental stages, from 22 varieties, to explore the potential for capturing full-length transcript isoforms. A total of 107,598 unique transcript isoforms were obtained, representing about 71% of the total number of predicted sugarcane genes. The majority of this dataset (92%) matched the plant protein database, while just over 2% was novel transcripts, and over 2% was putative long non-coding RNAs. About 56% and 23% of total sequences were annotated against the gene ontology and KEGG pathway databases, respectively. Comparison with de novo contigs from Illumina RNA-Sequencing (RNA-Seq) of the internode samples from the same experiment and public databases showed that the Iso-Seq method recovered more full-length transcript isoforms, had a higher N50 and average length of largest 1,000 proteins; whereas a greater representation of the gene content and RNA diversity was captured in RNA-Seq. Only 62% of PacBio transcript isoforms matched 67% of de novo contigs, while the non-matched proportions were attributed to the inclusion of leaf/root tissues and the normalization in PacBio, and the representation of more gene content and RNA classes in the de novo assembly, respectively. About 69% of PacBio transcript isoforms and 41% of de novo contigs aligned with the sorghum genome, indicating the high conservation of orthologs in the genic regions of the two genomes. CONCLUSIONS: The transcriptome dataset should contribute to improved sugarcane gene models and sugarcane protein predictions; and will serve as a reference database for analysis of transcript expression in sugarcane.


Asunto(s)
Perfilación de la Expresión Génica , Genómica , Poliploidía , Isoformas de ARN/genética , Saccharum/genética , Análisis de Secuencia de ARN , Empalme Alternativo , Etiquetas de Secuencia Expresada/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , ARN Mensajero/genética
7.
Plast Reconstr Surg ; 134(6): 1279-1284, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25415094

RESUMEN

BACKGROUND: Standards of cleft care abroad differ from those in the United States, particularly in less developed countries, where international adoption rates are high. Children adopted from these countries present to plastic surgeons in the United States at various ages and states of repair. The operative and perioperative needs of these children are poorly understood. This study attempts to characterize the preadoption history, the postadoption course, and surgical outcomes of children adopted with cleft deformities. METHODS: The authors performed a retrospective review of all adopted cleft lip-cleft palate patients presenting to an academic craniofacial referral center and compared outcomes among adopted children who were repaired abroad, adopted children who underwent repair performed by the two senior authors (C.R.D. and S.B.B.), and children born in the United States who underwent repair performed by one of the senior authors (S.B.B.) RESULTS: : Between May of 1993 and August of 2010, 83 adopted children with cleft deformities were evaluated in the authors' craniofacial center. Average age at adoption was 30.5 months (range, 5.0 to 95.0 months). Comparing outcomes among adopted children repaired abroad, adopted children repaired by the senior authors, and children born in the United States who underwent repair in the United States, the authors found no statistically significant differences in lip revision rates, fistula rates, or velopharyngeal insufficiency. CONCLUSIONS: Adopted cleft patients constitute a complex and variable population with high rates of revision and delayed presentation. Internationally adopted children with orofacial clefts fared no better or worse after undergoing primary cleft repair abroad or in the United States.


Asunto(s)
Adopción , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Emigrantes e Inmigrantes , Procedimientos de Cirugía Plástica/métodos , Niño , Femenino , Humanos , Lactante , Masculino , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento , Estados Unidos
8.
Psychol Serv ; 10(3): 350-2, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23937085

RESUMEN

The purpose of this program was to evaluate the benefits of integrating VA Care Coordination Home Telehealth and Telemental health within HBPC. A case study design was used to determine quality assurance and quality improvement of incorporating additional home telehealth equipment within Home Based Primary Care (HBPC). Veterans with complex medical conditions and their caregivers living in rural Oklahoma were enrolled. Veterans received the same care other HBPC patients received with the addition of home telehealth equipment. Members from the interdisciplinary treatment team were certified to use the telehealth equipment. Veterans and their caregivers were trained on use of the equipment in their homes. Standard HBPC program measures were used to assess the program success. Assessments from all disciplines on the HBPC team were at baseline, 3, and 6 months, and participants provided satisfaction and interview data to assess the benefits of integrating technology into standard care delivery within an HBPC program. Six veterans were enrolled (mean age = 72 yrs) with a range of physical health conditions including: chronic obstructive pulmonary disease, cerebrovascular accident, spinal cord injury, diabetes, hypertension, and syncope. Primary mental health conditions included depression, dementia, anxiety, and PTSD. Scores on the Mini-Mental State Examination ranged from 18 to 30. Over a 6-month period, case studies indicated improvements in strength, social functioning, decreased caregiver burden, and compliance with treatment plan. This integration of CCHT and HBPC served previously underserved rural veterans having complex medical conditions and appears both feasible and clinically beneficial to veterans and their caregivers.


Asunto(s)
Enfermedad Crónica/terapia , Servicios de Atención de Salud a Domicilio/organización & administración , Trastornos Mentales/terapia , Atención Primaria de Salud/organización & administración , Telemedicina/organización & administración , Anciano , Anciano de 80 o más Años , Humanos , Oklahoma , Manejo de Atención al Paciente/métodos , Manejo de Atención al Paciente/organización & administración , Proyectos Piloto , Atención Primaria de Salud/métodos , Salud Rural , Telemedicina/métodos , Resultado del Tratamiento , Veteranos/psicología
9.
Phys Med Biol ; 58(6): 1947-68, 2013 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-23459448

RESUMEN

Human exposure to radio frequency (RF) electromagnetic energy is known to result in tissue heating and can raise temperatures substantially in some situations. Standards for safe exposure to RF do not reflect bio-heat transfer considerations however. Thermoregulatory function (vasodilation, sweating) may mitigate RF heating effects in some environments and exposure scenarios. Conversely, a combination of an extreme environment (high temperature, high humidity), high activity levels and thermally insulating garments may exacerbate RF exposure and pose a risk of unsafe temperature elevation, even for power densities which might be acceptable in a normothermic environment. A high-resolution thermophysiological model, incorporating a heterogeneous tissue model of a seated adult has been developed and used to replicate a series of whole-body exposures at a frequency (100 MHz) which approximates that of human whole-body resonance. Exposures were simulated at three power densities (4, 6 and 8 mW cm(-2)) plus a sham exposure and at three different ambient temperatures (24, 28 and 31 °C). The maximum hypothalamic temperature increase over the course of a 45 min exposure was 0.28 °C and occurred in the most extreme conditions (T(AMB) = 31 °C, PD = 8 mW cm(-2)). Skin temperature increases attributable to RF exposure were modest, with the exception of a 'hot spot' in the vicinity of the ankle where skin temperatures exceeded 39 °C. Temperature increases in internal organs and tissues were small, except for connective tissue and bone in the lower leg and foot. Temperature elevation also was noted in the spinal cord, consistent with a hot spot previously identified in the literature.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Modelos Anatómicos , Ondas de Radio/efectos adversos , Temperatura , Adulto , Humanos , Temperatura Cutánea/efectos de la radiación , Sudoración/efectos de la radiación , Factores de Tiempo
10.
Infant Behav Dev ; 35(4): 829-37, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22986178

RESUMEN

Institutional care, particularly when experienced early in life, is associated with delays in social and emotional development that often persist years after adoption. It has been hypothesized that compromise of the hypothalamic-pituitary-adrenocortical (HPA) axis due to adverse condition in institutions is a mediator of later emotional and behavioral problems. The first goal of our project was to investigate whether improvements in the social and emotional environment are associated with changes in HPA axis function. The second goal was to explore whether HPA alterations related to early social adversity were associated with more compromised general development and social and emotional functioning post adoption. Children adopted from Eastern European orphanages (N = 76, mean age was 17 months, SD = 5) were followed as part of an ongoing longitudinal study. Data, including diurnal cortisol patterns, were collected at two time points: baseline (within one month of adoption) and follow-up (six months later). Cortisol values were averaged over two days of saliva sampling after wake-up and before bedtime. We found that morning cortisol values increased between the baseline assessment (M = 0.27 µg/dl, SD = 0.13) and follow-up (M = 0.33 µg/dl, SD = 0.20), t(76) = -2.1, p<0.05. HPA functioning was not associated with general developmental level at either the initial or six months post-adoption assessments. However, dysregulation of the HPA axis (i.e., flatter diurnal pattern) at follow-up was associated with more behavioral and emotional problems. Overall, these results suggest that investigating specific physiological mechanisms is important in identifying children at risk for persistent social and emotional problems and in understanding the long-term consequences of early adversity. Future work should investigate whether disturbance in the HPA system is a heightened risk for long-term negative developmental outcomes.


Asunto(s)
Adopción/psicología , Niño Institucionalizado/psicología , Sistema Hipotálamo-Hipofisario/fisiología , Sistema Hipófiso-Suprarrenal/fisiología , Estrés Psicológico/fisiopatología , Preescolar , Ritmo Circadiano/fisiología , Femenino , Estudios de Seguimiento , Humanos , Hidrocortisona/análisis , Lactante , Estudios Longitudinales , Masculino , Orfanatos , Saliva/química , Estrés Psicológico/psicología
11.
Bioelectromagnetics ; 31(8): 656-63, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20683908

RESUMEN

A macrophage assay and proteomic screening were used to investigate the biological activity of soluble factors in the plasma of millimeter wave-exposed rats. NR8383 rat macrophages were incubated for 24 h with 10% plasma from male Sprague-Dawley rats that had been exposed to sham conditions, or exposed to 42 °C environmental heat or 35 GHz millimeter waves at 75 mW/cm² until core temperature reached 41.0 °C. Two-dimensional polyacrylamide gel electrophoresis, image analysis, and Western blotting were used to analyze approximately 600 protein spots in the cell lysates for changes in protein abundance and levels of 3-nitrotyrosine, a marker of macrophage stimulation. Proteins of interest were identified using peptide mass fingerprinting. Compared to plasma from sham-exposed rats, plasma from environmental heat- or millimeter wave-exposed rats increased the expression of 11 proteins, and levels of 3-nitrotyrosine in seven proteins, in the NR8383 cells. These altered proteins are associated with inflammation, oxidative stress, and energy metabolism. Findings of this study indicate both environmental heat and 35 GHz millimeter wave exposure elicit the release of macrophage-activating mediators into the plasma of rats.


Asunto(s)
Proteínas Sanguíneas/metabolismo , Campos Electromagnéticos , Macrófagos/metabolismo , Macrófagos/efectos de la radiación , Proteómica/métodos , Animales , Línea Celular , Regulación de la Expresión Génica/efectos de la radiación , Calor , Masculino , Ratas , Ratas Sprague-Dawley , Tirosina/análogos & derivados , Tirosina/sangre
12.
Int J Pediatr Endocrinol ; 2010: 107252, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21234323

RESUMEN

Children raised in orphanages frequently experience growth suppression due to multiple risk factors. Placing such children in more nurturing environments through adoption leads to significant catch-up growth (CUG), the determinants of which are not entirely understood. The goal of this study was to perform an auxological evaluation and examine the degree and correlates of CUG in international adoptees. Children adopted from Eastern Europe, (n = 148, 71 males), 7 to 59 months of age, were recruited within 3 weeks of their arrival to the US. At baseline, mean height SDS was -1.2 ± 1.1 and 22% were <-2 SDS for height. IGF-1 and/or IGFBP-3 levels <-2 SDS were present in 32%. CUG, defined as a gain of >+0.5 in height SDS, was seen in 62% of adoptees at 6 months after adoption; 7% of children remained <-2 SDS for height (two had growth hormone deficiency). Growth factors improved in the majority of children. Younger age, greater degree of initial growth failure, and higher caloric intake were significantly associated with improved linear growth in multiple regression models. In summary, most adoptees demonstrate excellent CUG within six months after adoption. If growth failure persists after 6 months of appropriate caloric intake, nutrition-independent causes should be considered.

13.
Radiat Res ; 171(5): 615-21, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19580497

RESUMEN

The blood-brain barrier (BBB) consists of tight junctions between the endothelial cells that line the capillaries in the central nervous system. This structure protects the brain, and neurological damage could occur if it is compromised. Several publications by researchers at Lund University have reported alterations in the BBB after exposure to low-power 915 MHz energy. These publications increased the level of concern regarding the safety of wireless communication devices such as mobile phones. We performed a confirmation study designed to determine whether the BBB is altered in rats exposed in a transverse electromagnetic (TEM) transmission line cell to 915 MHz energy at parameters similar to those in the Lund University studies. Unanesthetized rats were exposed for 30 min to either continuous-wave or modulated (16 or 217 Hz) 915 MHz energy at power levels resulting in whole-body specific absorption rates (SARs) of 0.0018-20 W/kg. Albumin immunohistochemistry was performed on perfused brain tissue sections to determine the integrity of the BBB. Chi-square analysis revealed no significant increase in albumin extravasation in any of the exposed animals compared to the sham-exposed or home cage control animals.


Asunto(s)
Albúminas/farmacocinética , Barrera Hematoencefálica/efectos de la radiación , Ondas de Radio , Animales , Inmunohistoquímica , Masculino , Dosis de Radiación , Ratas , Ratas Endogámicas F344
14.
Radiat Res ; 169(3): 288-300, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18302488

RESUMEN

To better understand the cellular and molecular responses to overexposure to millimeter waves, alterations in the gene expression profile and histology of skin after exposure to 35 GHz radiofrequency radiation were investigated. Rats were subjected to sham exposure, to 42 degrees C environmental heat, or to 35 GHz millimeter waves at 75 mW/cm(2). Skin samples were collected at 6 and 24 h after exposure for Affymetrix GeneChip analysis. The skin was harvested from a separate group of rats at 3-6 h or 24-48 h after exposure for histopathology analysis. Microscopic findings observed in the dermis of rats exposed to 35 GHz millimeter waves included aggregation of neutrophils in vessels, degeneration of stromal cells, and breakdown of collagen. Changes were detected in 56 genes at 6 h and 58 genes at 24 h in the millimeter-wave-exposed rats. Genes associated with regulation of transcription, protein folding, oxidative stress, immune response, and tissue matrix turnover were affected at both times. At 24 h, more genes related to extracellular matrix structure and chemokine activity were altered. Up-regulation of Hspa1a, Timp1, S100a9, Ccl2 and Angptl4 at 24 h by 35 GHz millimeter-wave exposure was confirmed by real-time RT-PCR. These results obtained from histopathology, microarrays and RT-PCR indicate that prolonged exposure to 35 GHz millimeter waves causes thermally related stress and injury in skin while triggering repair processes involving inflammation and tissue matrix recovery.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Regulación de la Expresión Génica/efectos de la radiación , Microondas , Especies Reactivas de Oxígeno/metabolismo , Temperatura Cutánea/efectos de la radiación , Piel/metabolismo , Piel/efectos de la radiación , Animales , Citocinas/metabolismo , Relación Dosis-Respuesta en la Radiación , Proteínas de la Matriz Extracelular/metabolismo , Proteínas de Choque Térmico/metabolismo , Calor , Masculino , Dosis de Radiación , Ratas , Ratas Sprague-Dawley
15.
Shock ; 25(6): 625-32, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16721271

RESUMEN

Electromagnetic fields at millimeter wave lengths are being developed for commercial and military use at power levels that can cause temperature increases in the skin. Previous work suggests that sustained exposure to millimeter waves causes greater heating of skin, leading to faster induction of circulatory failure than exposure to environmental heat (EH). We tested this hypothesis in three separate experiments by comparing temperature changes in skin, subcutis, and colon, and the time to reach circulatory collapse (mean arterial blood pressure, 20 mmHg) in male Sprague-Dawley rats exposed to the following conditions that produced similar rates of body core heating within each experiment: (1) EH at 42 degrees C, 35 GHz at 75 mW/cm, or 94 GHz at 75 mW/cm under ketamine and xylazine anesthesia; (2) EH at 43 degrees C, 35 GHz at 90 mW/cm, or 94 GHz at 90 mW/cm under ketamine and xylazine anesthesia; and (3) EH at 42 degrees C, 35 GHz at 90 mW/cm, or 94 GHz at 75 mW/cm under isoflurane anesthesia. In all three experiments, the rate and amount of temperature increase at the subcutis and skin surface differed significantly in the rank order of 94 GHz more than 35 GHz more than EH. The time to reach circulatory collapse was significantly less only for rats exposed to 94 GHz at 90 mW/cm, the group with the greatest rate of skin and subcutis heating of all groups in this study, compared with both the 35 GHz at 90 mW/cm and the EH at 43 degrees C groups. These data indicate that body core heating is the major determinant of induction of hemodynamic collapse, and the influence of heating of the skin and subcutis becomes significant only when a certain threshold rate of heating of these tissues is exceeded.


Asunto(s)
Temperatura Corporal/efectos de la radiación , Colon/efectos de la radiación , Hemodinámica/efectos de la radiación , Calor/efectos adversos , Microondas/efectos adversos , Piel/efectos de la radiación , Animales , Colon/irrigación sanguínea , Relación Dosis-Respuesta en la Radiación , Masculino , Ratas , Ratas Sprague-Dawley , Piel/irrigación sanguínea
16.
Pediatr Clin North Am ; 52(5): 1351-68, vii, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16154467

RESUMEN

Growth delay is one of the most common and persistent findings in children who have been adopted from abroad. Although the cause is not clearly understood, it may be related to the observed phenomenon of psychosocial short stature described in children from abusive and neglectful settings in western countries. Fortunately, adopted children generally experience significant improvement in growth after joining their new family, but this may put girls at risk for early and rapidly progressing puberty. This review should help the health care team to understand these issues and work better with the adoptive parents to ensure a child's smooth transition into family life.


Asunto(s)
Adopción , Estatura , Trastornos del Crecimiento/etiología , Estado de Salud , Pubertad Precoz/etiología , Pubertad , Niño , Protección a la Infancia , Femenino , Crecimiento , Trastornos del Crecimiento/terapia , Humanos , Masculino , Padres/educación , Pubertad Tardía/etiología , Factores de Riesgo , Factores Sexuales , Estados Unidos
17.
Semin Speech Lang ; 26(1): 1-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15731965

RESUMEN

Adoptions from international countries have become an option for many US families, with over 150,000 children adopted in the past 14 years. Typically, internationally adopted children present with a host of medical and developmental concerns. Issues such as growth stunting, abnormal behaviors, and significant delays in motor, speech, and language development are likely directly related to the prenatal and early postnatal environment experienced prior to adoption. The new family and its health-care team must quickly work to identify and address these issues to aid the child's integration into his or her new family. This article will examine potential issues seen in children who are being adopted, including the impact of early environment on subsequent development. We will summarize early and long-term medical issues and review the extent of developmental delays seen in children adopted internationally. Finally, we will discuss possible mechanisms leading to the observed delays, including the impact of stress on subsequent development. By understanding the extent of expected delays and the mechanisms likely causing the issues, the health-care team will be in a good position to quickly identify and develop intervention protocols that will foster the child's assimilation into his or her new family.


Asunto(s)
Adopción/etnología , Adopción/psicología , Discapacidades del Desarrollo/etiología , Infecciones/etiología , Internacionalidad , Trastornos del Desarrollo del Lenguaje/etiología , Trastornos del Habla/etiología , Aculturación , Nivel de Alerta/fisiología , Niño , Niño Institucionalizado/psicología , Estudios Transversales , Discapacidades del Desarrollo/epidemiología , Discapacidades del Desarrollo/fisiopatología , Discapacidades del Desarrollo/psicología , Europa Oriental/etnología , Humanos , Sistema Hipotálamo-Hipofisario/fisiopatología , Infecciones/epidemiología , Infecciones/fisiopatología , Infecciones/psicología , Trastornos del Desarrollo del Lenguaje/epidemiología , Trastornos del Desarrollo del Lenguaje/fisiopatología , Trastornos del Desarrollo del Lenguaje/psicología , Orfanatos/estadística & datos numéricos , Grupo de Atención al Paciente , Sistema Hipófiso-Suprarrenal/fisiopatología , Pobreza/estadística & datos numéricos , Pronóstico , Factores de Riesgo , Medio Social , Trastornos del Habla/epidemiología , Trastornos del Habla/fisiopatología , Trastornos del Habla/psicología , Estrés Psicológico/complicaciones , Estados Unidos
18.
J Pediatr Endocrinol Metab ; 17(5): 711-7, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15237704

RESUMEN

Pediatric patients with brain tumors can loose 1 SD of height prior to beginning growth hormone (GH) therapy. The objectives of this study were to characterize the early growth failure, identify contributing factors and propose interventions. Five children were followed quarterly for 2 years to monitor auxological parameters, nutritional indices, and endocrine measuremnts. GH stimulation tests were done every 6 months to determine the timing of the onset of GH deficiency. The nadir for height velocity (HV) occurred 6 months after diagnosis. Poor gains in height correlated with decreased calorie count (p <0.001), poor weight gain (p <0.001), decreased BMI (p <0.001) and lowered leptin levels (p <0.001). All patients were able to secrete GH normally during this nadir of growth. Children treated for brain tumors demonstrate an early triphasic pattern of growth. Growth failure due to cachexia occurs first, then a second transient phase of normal growth is observed followed by a third phase of growth failure due to GH deficiency. Phase 1 is characterized by decreased HV, BMI, leptin levels and calorie counts. With recognition of this profile, the early growth failure might be preventable with aggressive nutritional rehabilitation.


Asunto(s)
Estatura/efectos de la radiación , Neoplasias Encefálicas/radioterapia , Irradiación Craneana/efectos adversos , Trastornos del Crecimiento/etiología , Hormona de Crecimiento Humana/deficiencia , Hipotálamo/efectos de la radiación , Neoplasias Neuroepiteliales/radioterapia , Antineoplásicos/uso terapéutico , Estatura/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Caquexia/fisiopatología , Niño , Preescolar , Terapia Combinada , Femenino , Estudios de Seguimiento , Trastornos del Crecimiento/sangre , Trastornos del Crecimiento/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Hipotálamo/fisiopatología , Leptina/sangre , Masculino , Neoplasias Neuroepiteliales/tratamiento farmacológico , Traumatismos por Radiación/complicaciones , Sobrevivientes
19.
Health Phys ; 86(2): 115-20, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14744044

RESUMEN

We have previously reported species differences in the rate of skin heating in response to millimeter wavelength microwave exposure. We hypothesized that these differences were predominantly a function of species differences in the ability to increase skin blood flow during local heating. Mathematical modeling also suggested that, in humans, the rate of skin heating during prolonged millimeter wavelength exposure would be dependent on skin blood flow. In order to empirically test this hypothesis, we determined the role of baseline skin blood flow on the rate of cutaneous heating induced by 94-GHz microwave energy in humans (3 female, 3 male) using infrared thermography and laser Doppler imaging to measure skin temperature and relative skin blood flow, respectively. Millimeter wavelength exposure intensities used were high power (HP), 1 W x cm(-2) for 4 s and low power, 175 mW cm(-2) for 180 s. Skin blood flow was (a) normal, (b) eliminated using a blood pressure cuff to occlude forearm blood flow, or (c) elevated by heating the skin prior to irradiation. Results showed that for the HP exposures, these manipulations did not influence the rate of skin heating. For the low power exposures, occlusion of baseline skin blood flow had a small impact on the subsequent rate of heating. In contrast, a two-fold elevation in baseline skin blood flow had a profound impact on the subsequent rate of heating, resulting in a substantially lower rate of heating. Occlusion of an elevated skin blood flow reversed this lower rate of heating. The results of these studies demonstrate that relatively small changes in skin blood flow may produce substantial alterations in the rate of skin heating during prolonged 94-GHz exposure.


Asunto(s)
Microondas , Temperatura Cutánea/fisiología , Temperatura Cutánea/efectos de la radiación , Piel/irrigación sanguínea , Piel/efectos de la radiación , Adaptación Fisiológica/efectos de la radiación , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Velocidad del Flujo Sanguíneo/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Femenino , Antebrazo/irrigación sanguínea , Antebrazo/fisiología , Antebrazo/efectos de la radiación , Calor , Humanos , Flujometría por Láser-Doppler/métodos , Masculino , Dosis de Radiación , Termografía/métodos
20.
Pediatr Nurs ; 30(6): 483-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15704598

RESUMEN

Internationally adopted children come from high risk environments that differ significantly from those of children born and raised in the United States. This can impact their developmental and parenting needs. Aware adoptive parents can do many things to lessen the effects of a highly deprived early start to life and encourage optimal development. However, preconceived ideas and myths about adoption often stand in the way of parental desires to provide the best for their newly adopted child. Pediatric nurses aware of these common myths can educate and support adoptive parents in the early identification of potential concerns and in addressing and ameliorating them. Preparation, planning, and use of professional resources, as needed, can assist parents in supporting the child's development and in achieving successful integration of the internationally adopted child into their new family.


Asunto(s)
Adopción , Cuidado del Niño/métodos , Padres/educación , Adopción/psicología , Actitud Frente a la Salud , Niño , Cuidado del Niño/psicología , Desarrollo Infantil , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud , Estado de Salud , Humanos , Servicios de Información , Internet , Amor , Evaluación de Necesidades , Rol de la Enfermera , Apego a Objetos , Relaciones Padres-Hijo , Padres/psicología , Enfermería Pediátrica/métodos , Pobreza/psicología , Factores de Riesgo , Apoyo Social
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