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1.
Int J Nurs Sci ; 10(2): 158-166, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37095850

RESUMEN

This paper identifies key factors rooted in the systemic failings of the long-term care sector amongst four high income countries during the COVID-19 pandemic. The goal is to offer practice and policy solutions to prevent future tragedies. Based on data from Australia, Canada, Spain and the United States, the findings support evidence-based recommendations at macro, meso and micro levels of practice and policy intervention. Key macro recommendations include improving funding, transparency, accountability and health system integration; and promoting not-for-profit and government-run long-term care facilities. The meso recommendation involves moving from warehouses to "green houses." The micro recommendations emphasize mandating recommended staffing levels and skill mix; providing infection prevention and control training; establishing well-being and mental health supports for residents and staff; building evidence-based practice cultures; ensuring ongoing education for staff and nursing students; and fully integrating care partners, such as families or friends, into the healthcare team. Enacting these recommendations will improve residents' safety and quality of life, families' peace of mind, and staff retention and work satisfaction.

3.
Am J Infect Control ; 49(2): 226-228, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32652255

RESUMEN

We report on innovating protocols at an Academic Pediatric practice during the COVID-19 (2019 novel coronavirus) crisis. Facing the challenges of limited personal protective equipment and testing capacity, we rapidly and efficiently changed processes to optimize infection control, providing safe and effective care for our vulnerable population.


Asunto(s)
Centros Médicos Académicos/organización & administración , COVID-19/prevención & control , Servicios de Salud del Niño/organización & administración , Control de Infecciones/organización & administración , Niño , Humanos , Control de Infecciones/métodos , Equipo de Protección Personal/provisión & distribución , SARS-CoV-2
4.
Pediatrics ; 136(6): 1044-50, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26527548

RESUMEN

BACKGROUND AND OBJECTIVES: Research on children's use of mobile media devices lags behind its adoption. The objective of this study was to examine young children's exposure to and use of mobile media devices. METHODS: Cross-sectional study of 350 children aged 6 months to 4 years seen October to November 2014 at a pediatric clinic in an urban, low-income, minority community. The survey was adapted from Common Sense Media's 2013 nationwide survey. RESULTS: Most households had television (97%), tablets (83%), and smartphones (77%). At age 4, half the children had their own television and three-fourths their own mobile device. Almost all children (96.6%) used mobile devices, and most started using before age 1. Parents gave children devices when doing house chores (70%), to keep them calm (65%), and at bedtime (29%). At age 2, most children used a device daily and spent comparable screen time on television and mobile devices. Most 3- and 4-year-olds used devices without help, and one-third engaged in media multitasking. Content delivery applications such as YouTube and Netflix were popular. Child ownership of device, age at first use, and daily use were not associated with ethnicity or parent education. CONCLUSIONS: Young children in an urban, low-income, minority community had almost universal exposure to mobile devices, and most had their own device by age 4. The patterns of use suggest early adoption, frequent and independent use, and media multitasking. Studies are urgently needed to update recommendations for families and providers on the use of mobile media by young children.


Asunto(s)
Teléfono Celular/estadística & datos numéricos , Computadoras de Mano/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Televisión/estadística & datos numéricos , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Padres , Encuestas y Cuestionarios
5.
PLoS One ; 10(7): e0131881, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26196397

RESUMEN

We introduce and describe a novel non-invasive in-vivo method for mapping local rod rhodopsin distribution in the human retina over a 30-degree field. Our approach is based on analyzing the brightening of detected lipofuscin autofluorescence within small pixel clusters in registered imaging sequences taken with a commercial 488nm confocal scanning laser ophthalmoscope (cSLO) over a 1 minute period. We modeled the kinetics of rhodopsin bleaching by applying variational optimization techniques from applied mathematics. The physical model and the numerical analysis with its implementation are outlined in detail. This new technique enables the creation of spatial maps of the retinal rhodopsin and retinal pigment epithelium (RPE) bisretinoid distribution with an ≈ 50µm resolution.


Asunto(s)
Modelos Biológicos , Células Fotorreceptoras Retinianas Bastones/citología , Células Fotorreceptoras Retinianas Bastones/metabolismo , Rodopsina/metabolismo , Humanos
6.
Methods Mol Biol ; 755: 57-66, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21761293

RESUMEN

Over the past 15 years, laser-based microdissection has improved the precision by which scientists can procure cells of interest from a heterogeneous tissue section. However, for studies that require a large amount of material (e.g., proteomics) or for cells that are scattered and difficult to identify by standard histological stains, an immunostain-based, automated approach becomes essential. In this chapter, we discuss the use of immunohistochemistry (IHC) and immunofluorescence (IF) to guide the microdissection process via manual and software-driven auto-dissection methods. Although technical challenges still exist with these innovative approaches, we present here methods and protocols to successfully perform immuno-based microdissection on commercially available laser dissection systems.


Asunto(s)
Inmunohistoquímica/métodos , Rayos Láser , Microdisección/métodos , Separación Celular/métodos , Criopreservación , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Queratinas/metabolismo , Masculino , Adhesión en Parafina , Próstata/citología , Próstata/metabolismo , Programas Informáticos , Fijación del Tejido
7.
BMC Proc ; 5 Suppl 2: S3, 2011 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-21554761

RESUMEN

BACKGROUND: The gene networks underlying closure of the optic fissure during vertebrate eye development are not well-understood. We use a novel clustering method based on nonlinear dimension reduction with data labeling to analyze microarray data from laser capture microdissected (LCM) cells at the site and developmental stages (days 10.5 to 12.5) of optic fissure closure. RESULTS: Our nonlinear methods created clusters of genes that mapped onto more specific biological processes and functions related to eye development as defined by Gene Ontology at lower false discovery rates than conventional linear cluster algorithms. Our new methods build on the advantages of LCM to isolate pure phenotypic populations within complex tissues in order to identify systems biology relationships among critical gene products expressed at lower copy number. CONCLUSIONS: The combination of LCM of embryonic organs, gene expression microarrays, and nonlinear dimension reduction with labeling is a potentially useful approach to extract subtle spatial and temporal co-variations within the gene regulatory networks that specify mammalian organogenesis and organ function. Our results motivate further analysis of nonlinear dimension reduction with labeling within other microarray data sets from LCM dissected tissues or other cell specific samples to determine the more general utility of our method for uncovering more specific biological functional relationships.

8.
Nat Protoc ; 6(4): 457-67, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21412274

RESUMEN

Laser-based microdissection facilitates the isolation of specific cell populations from clinical or animal model tissue specimens for molecular analysis. Expression microdissection (xMD) is a second-generation technology that offers considerable advantages in dissection capabilities; however, until recently the method has not been accessible to investigators. This protocol describes the adaptation of xMD to commonly used laser microdissection instruments and to a commercially available handheld laser device in order to make the technique widely available to the biomedical research community. The method improves dissection speed for many applications by using a targeting probe for cell procurement in place of an operator-based, cell-by-cell selection process. Moreover, xMD can provide improved dissection precision because of the unique characteristics of film activation. The time to complete the protocol is highly dependent on the target cell population and the number of cells needed for subsequent molecular analysis.


Asunto(s)
Rayos Láser , Microdisección/métodos , Separación Celular , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica/métodos , Microdisección/instrumentación , Polivinilos/química
9.
BMC Bioinformatics ; 12: 52, 2011 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-21310028

RESUMEN

BACKGROUND: The Gene Ontology (GO) Consortium organizes genes into hierarchical categories based on biological process, molecular function and subcellular localization. Tools such as GoMiner can leverage GO to perform ontological analysis of microarray and proteomics studies, typically generating a list of significant functional categories. Two or more of the categories are often redundant, in the sense that identical or nearly-identical sets of genes map to the categories. The redundancy might typically inflate the report of significant categories by a factor of three-fold, create an illusion of an overly long list of significant categories, and obscure the relevant biological interpretation. RESULTS: We now introduce a new resource, RedundancyMiner, that de-replicates the redundant and nearly-redundant GO categories that had been determined by first running GoMiner. The main algorithm of RedundancyMiner, MultiClust, performs a novel form of cluster analysis in which a GO category might belong to several category clusters. Each category cluster follows a "complete linkage" paradigm. The metric is a similarity measure that captures the overlap in gene mapping between pairs of categories. CONCLUSIONS: RedundancyMiner effectively eliminated redundancies from a set of GO categories. For illustration, we have applied it to the clarification of the results arising from two current studies: (1) assessment of the gene expression profiles obtained by laser capture microdissection (LCM) of serial cryosections of the retina at the site of final optic fissure closure in the mouse embryos at specific embryonic stages, and (2) analysis of a conceptual data set obtained by examining a list of genes deemed to be "kinetochore" genes.


Asunto(s)
Minería de Datos/métodos , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Proteómica/métodos , Algoritmos , Animales , Análisis por Conglomerados , Biología Computacional/métodos , Ratones , Programas Informáticos
10.
J Pediatr ; 158(4): 628-633.e1, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21075381

RESUMEN

OBJECTIVE: To evaluate whether oxidative stress is correlated with adiposity, obesity-related metabolic abnormalities, and ambulatory blood pressure (ABP) in a multi-ethnic pediatric population. STUDY DESIGN: We conducted a prospective study enrolling 42 obese children (age, 12.8 ± 2.4 years) and 34 non-obese children (age, 11.8 ± 3.4 years). We measured urine 8-isoprostane and hydrogen peroxide (markers of oxidative stress) in both obese and non-obese groups. In the obese group, we measured the 24-hour ABP and obtained an oral glucose tolerance test, lipid panel, interleukin-6, and tumor necrosis factor-α. RESULTS: 8-isoprostane and hydrogen peroxide were correlated with body mass index standard deviation score and waist circumference. The mean 8-isoprostane and hydrogen peroxide levels of the obese group were higher than those of the non-obese group. In the subset of obese subjects who underwent ABP monitoring, 8-isoprostane was correlated with mean 24-hour systolic blood pressure: within the obese group, 8-isoprostane was higher in obese children with elevated mean 24-hour systolic blood pressure. CONCLUSIONS: Our findings provide evidence of a significant correlation between oxidative stress, adiposity, and blood pressure in children. Longitudinal studies in a larger population sample are needed to validate the association between elevated urine 8-isoprostane level and cardiovascular risk factors in an obese pediatric population.


Asunto(s)
Hipertensión/fisiopatología , Obesidad/fisiopatología , Estrés Oxidativo/fisiología , Adolescente , Niño , Estudios Transversales , Dinoprost/análogos & derivados , Dinoprost/orina , Dislipidemias/epidemiología , Dislipidemias/etnología , Femenino , Humanos , Peróxido de Hidrógeno/orina , Hipertensión/etnología , Interleucina-6/sangre , Masculino , Obesidad/epidemiología , Obesidad/etnología , Obesidad/orina , Estudios Prospectivos , Factor de Necrosis Tumoral alfa/sangre
11.
Am J Ophthalmol ; 148(4): 573-83, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19573860

RESUMEN

PURPOSE: To use multiple imaging methods to investigate patients with type 2 idiopathic macular telangiectasia (IMT) at different disease severity stages so as to characterize and categorize disease progression through the full spectrum of disease phenotypes. DESIGN: Observational case series. METHODS: Twelve patients with type 2 IMT (22 eyes) examined with fundus photography, angiography, optical coherence tomography imaging, fundus autofluorescence (FAF), and microperimetry testing in an institutional setting. RESULTS: Eyes examined by multiple imaging methods were classified into 5 proposed categories (0 through 4): category 0 (fellow) eyes had normal results on all imaging methods. Category 1 eyes had increased foveal autofluorescence on FAF imaging as the only imaging abnormality. Category 2 eyes had increased foveal autofluorescence together with funduscopic and angiographic features typical of type 2 IMT. Category 3 eyes had additional evidence of foveal atrophy on optical coherence tomography, and category 4 eyes had all the above features plus clinically evident pigment clumping. FAF signal increased in intensity in the foveal region from category 0 through category 3, whereas category 4 eyes demonstrated a mixed pattern of increased and decreased FAF signal. CONCLUSIONS: The findings here outline a sequence of progressive changes seen with multiple imaging methods in advancing stages of disease. Increase in foveal autofluorescence is an early anatomic change in type 2 IMT that may precede typical clinical and angiographic changes. Loss of macular pigment density in the fovea and a changing composition of fluorophores in the retinal pigment epithelium may underlie these changes on FAF in the fundus.


Asunto(s)
Diagnóstico por Imagen/métodos , Técnicas de Diagnóstico Oftalmológico , Enfermedades de la Retina/diagnóstico , Vasos Retinianos/patología , Telangiectasia/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Colorantes , Estudios Transversales , Progresión de la Enfermedad , Femenino , Angiografía con Fluoresceína , Fluorescencia , Fondo de Ojo , Humanos , Verde de Indocianina , Masculino , Persona de Mediana Edad , Fotograbar , Enfermedades de la Retina/fisiopatología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Telangiectasia/fisiopatología , Tomografía de Coherencia Óptica , Pruebas del Campo Visual
12.
Proc Natl Acad Sci U S A ; 106(5): 1462-7, 2009 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-19171890

RESUMEN

The gene networks underlying closure of the optic fissure during vertebrate eye development are poorly understood. Here, we profile global gene expression during optic fissure closure using laser capture microdissected (LCM) tissue from the margins of the fissure. From these data, we identify a unique role for the C(2)H(2) zinc finger proteins Nlz1 and Nlz2 in normal fissure closure. Gene knockdown of nlz1 and/or nlz2 in zebrafish leads to a failure of the optic fissure to close, a phenotype which closely resembles that seen in human uveal coloboma. We also identify misregulation of pax2 in the developing eye of morphant fish, suggesting that Nlz1 and Nlz2 act upstream of the Pax2 pathway in directing proper closure of the optic fissure.


Asunto(s)
Proteínas de Unión al ADN/genética , Ojo/embriología , Perfilación de la Expresión Génica , Proteínas Represoras/genética , Proteínas de Pez Cebra/genética , Animales , Secuencia de Bases , Coloboma/genética , Cartilla de ADN , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Factor de Transcripción PAX2/genética , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , ARN Mensajero/genética , Pez Cebra , Dedos de Zinc
13.
Ophthalmic Res ; 40(3-4): 124-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18421225

RESUMEN

BACKGROUND/AIMS: Senescent Ccl2-/- mice develop cardinal features of human age-related macular degeneration (AMD). Loss-of-function single-nucleotide polymorphisms within CX3CR1 are associated with AMD. METHODS: We generated Ccl2-/-/Cx3cr1-/- [double-knockout (DKO)] mice and evaluated the eyes using fundoscopy routine histology, immunochemistry, biochemistry and proteomics. RESULTS: At 6 weeks old, all DKO mice developed AMD-like retinal lesions such as abnormal retinal pigment epithelium cells, drusen, photoreceptor atrophy and choroidal neovascularization, which progressed with age and reversed with high omega-3 long-chain polyunsaturated fatty acid diet. N-retinylidene-N-retinylethanolamine (A2E), a major lipofuscin fluorophore, illustrated by an emission peak at approximately 600 nm, was significantly higher in DKO retinal pigment epithelium. Decreased ERp29 was found in the retina of DKO mice. CONCLUSION: A broad spectrum of AMD pathologies with early onset and high penetrance in these mice implicate certain chemokines, A2E and endoplasmic reticulum proteins in AMD pathogenesis.


Asunto(s)
Quimiocina CCL2/deficiencia , Degeneración Macular/metabolismo , Epitelio Pigmentado Ocular/metabolismo , Receptores de Quimiocina/deficiencia , Animales , Receptor 1 de Quimiocinas CX3C , Citocinas , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Degeneración Macular/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Epitelio Pigmentado Ocular/ultraestructura
14.
BMC Genomics ; 7: 97, 2006 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-16643667

RESUMEN

BACKGROUND: Gene expression profiling by microarray analysis of cells enriched by laser capture microdissection (LCM) faces several technical challenges. Frozen sections yield higher quality RNA than paraffin-imbedded sections, but even with frozen sections, the staining methods used for histological identification of cells of interest could still damage the mRNA in the cells. To study the contribution of staining methods to degradation of results from gene expression profiling of LCM samples, we subjected pellets of the mouse plasma cell tumor cell line TEPC 1165 to direct RNA extraction and to parallel frozen sectioning for LCM and subsequent RNA extraction. We used microarray hybridization analysis to compare gene expression profiles of RNA from cell pellets with gene expression profiles of RNA from frozen sections that had been stained with hematoxylin and eosin (H&E), Nissl Stain (NS), and for immunofluorescence (IF) as well as with the plasma cell-revealing methyl green pyronin (MGP) stain. All RNAs were amplified with two rounds of T7-based in vitro transcription and analyzed by two-color expression analysis on 10-K cDNA microarrays. RESULTS: The MGP-stained samples showed the least introduction of mRNA loss, followed by H&E and immunofluorescence. Nissl staining was significantly more detrimental to gene expression profiles, presumably owing to an aqueous step in which RNA may have been damaged by endogenous or exogenous RNAases. CONCLUSION: RNA damage can occur during the staining steps preparatory to laser capture microdissection, with the consequence of loss of representation of certain genes in microarray hybridization analysis. Inclusion of RNAase inhibitor in aqueous staining solutions appears to be important in protecting RNA from loss of gene transcripts.


Asunto(s)
Perfilación de la Expresión Génica , Microdisección/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN/análisis , Animales , Línea Celular Tumoral , Rayos Láser , Verde de Metilo/farmacología , Ratones , Microscopía Fluorescente , Hibridación de Ácido Nucleico , Pironina/farmacología , ARN/metabolismo , Coloración y Etiquetado/métodos
15.
J Transl Med ; 4: 13, 2006 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-16512911

RESUMEN

BACKGROUND: A functional blood supply is essential for tumor growth and proliferation. However, the mechanism of blood vessel recruitment to the tumor is still poorly understood. Ideally, a thorough molecular assessment of blood vessel cells would be critical in our comprehension of this process. Yet, to date, there is little known about the molecular makeup of the endothelial cells of tumor-associated blood vessels, due in part to the difficulty of isolating a pure population of endothelial cells from the heterogeneous tissue environment. METHODS: Here we describe the use of a recently developed technique, Expression Microdissection, to isolate endothelial cells from the tumor microenvironment. The methylation status of the dissected samples was evaluated for GSTP1 and RARbeta2 promoters via the QMS-PCR method. RESULTS: Comparing GSTP1 and RARbeta2 promoter methylation data, we show that 100% and 88% methylation is detected, respectively, in the tumor areas, both in epithelium and endothelium. Little to no methylation is observed in non-tumor tissue areas. CONCLUSION: We applied an accurate microdissection technique to isolate endothelial cells from tissues, enabling DNA analysis such as promoter methylation status. The observations suggest that epigenetic alterations may play a role in determining the phenotype of tumor-associated vasculature.

16.
Transfusion ; 45(2 Suppl): 72S-80S, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16086792

RESUMEN

BACKGROUND: There is continuing interest in the development of in vitro tests evaluating the in vivo function, recovery, and survival of platelets stored for transfusion. A recent forum concluded that no completely reliable test exists, although discoid morphology indicates a platelet's good health. We evaluated a novel device, the NAPSAC (Noninvasive Assessment of Platelet Shape and Concentration), designed to determine noninvasively the proportion of discoid platelets in a stored concentrate, as well as platelet concentration. STUDY DESIGN AND METHODS: Twenty-eight plateletapheresis concentrates stored 24 hours in PL-146 were evaluated. Percent discoid platelet results were correlated with radiolabeled autologous recovery and survival performed using 111Indium oxyquinoline and calculated using linear (L) and multiple-hit (M) models. pH of 8 concentrates was raised at the end of storage with 6N NaOH. Platelet concentration measured by NAPSAC and Coulter Thrombocounter C was compared in 256 plateletapheresis products. RESULTS: Percent discoid platelets at 24 hours did not correlate significantly with platelet recovery or survival (recovery L = 0.29, M = 0.28; survival L = 0.16, M = 0.03). Raising the pH (mean 6.38 to 6.94) resulted in a significant increase in percent discoid platelets (21% to 41%). Platelet concentration values for both methods studied were linearly correlated with a slope of 1.01 +/- 0.03, r = 0.81. CONCLUSION: Percent discoid platelets was not predictive of posttransfusion platelet recovery or survival. The results suggest that non-discoid platelets may survive posttransfusion and even revert to discoid shape, since raising the pH approximately doubled the percent of discoid platelets. The NAPSAC was shown to be a reliable instrument for noninvasively determining platelet concentration in PL-146 concentrates.


Asunto(s)
Plaquetas/citología , Plaquetas/fisiología , Supervivencia Celular , Transfusión de Plaquetas , Conservación de la Sangre , Femenino , Humanos , Radioisótopos de Indio , Masculino , Plaquetoferesis
17.
Hum Reprod ; 20(2): 476-83, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15576398

RESUMEN

BACKGROUND: The factors involved in oocyte survival and transition from quiescence to the growing phenotype remain unknown. Herein we report genes that are differentially expressed in the primordial oocyte revealed by DNA arrays. METHODS: Primordial oocytes were captured selectively in rhesus monkey ovary sections using laser capture microdissection. The RNA was extracted and amplified in two rounds by T7-based linear RNA amplification, fluorescence labelled and then hybridized to human cDNA arrays containing 7680 elements. RNA from human placenta served as a reference sample. RESULTS: Ninety-five genes were found to be consistently expressed at a higher level in primordial oocytes. Expression of several of these genes in the oocyte has been reported before, e.g. deleted in azoospermia (DAZ), prohibitin and transglutaminase 2. Oocyte expression of several novel transcripts revealed on array hybridization, such as gene 33, ubiquitin-conjugating enzyme E2A, G1 to S phase transition 1, growth arrest and DNA damage-inducible (GADD), and dendritic cell-derived ubiquitin-like protein (DC-UbP) was confirmed by in situ hybridization. Some array-identified gene products [integrin beta3, alpha-tubulin, regulatory telomere elongation protein (RAP1) and cellular repressor of EIA-stimulated genes (CREG protein)] were detected in human oocytes by immunofluorescence. Bioinformatic analysis of the oocyte-enriched transcripts reveals a functional profile summarized as follows: cell cycle (14%); transporter (13%); signal transduction (10%); cytoskeletal (7%); transcription factor (5%); immune response (5%); apoptosis-related (5%); RNA processing (5%); and the remainder of miscellaneous categories. CONCLUSIONS: These observations may contribute to the elucidation of molecular pathways involved in oocyte survival and maturation.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de Secuencia por Matrices de Oligonucleótidos , Oocitos/citología , Oocitos/fisiología , Animales , Bases de Datos Genéticas , Femenino , Macaca mulatta , Folículo Ovárico/citología , Folículo Ovárico/fisiología
18.
Diagn Mol Pathol ; 13(4): 207-12, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15538110

RESUMEN

Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting. Expression microdissection (xMD) offers significant advantages over available methods, including an increase in dissection speed of several orders of magnitude. xMD may become a valuable tool for investigators studying cancer or other disease states in patient specimens and animal models.


Asunto(s)
Separación Celular/métodos , Disección/métodos , Perfilación de la Expresión Génica/métodos , Micromanipulación/métodos , Animales , Disección/instrumentación , Genómica , Humanos , Inmunohistoquímica , Rayos Láser , Proteómica
19.
Laryngoscope ; 114(12): 2123-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15564832

RESUMEN

OBJECTIVES: To quantify gene expression in tumor cells from human head and neck squamous cell carcinomas (HNSCC) using laser capture microdissection (LCM). STUDY DESIGN: Histopathologically identified HNSCC cells were microdissected from frozen sections, RNA was isolated, and vascular endothelial growth factor (VEGF) gene expression was measured by real-time reverse transcriptase polymerase chain reaction (RT-PCR). MATERIALS AND METHODS: Two human HNSCC tumor samples and matched normal mucosal biopsies and five human xenograft tumor specimens were harvested, embedded, and frozen in OCT. The frozen tumors were sectioned to 8 to 10 mum in thickness, and hematoxylin-eosin (H&E) staining was performed before LCM. An estimated 2,000 to 3,000 tumor cells were microdissected from frozen sections and processed for RNA isolation. mRNA for VEGF was analyzed by real time RT-PCR (TaqMan) with commercially available primers and probes. RESULTS: Two thousand to 3000 cells were necessary to obtain a suitable quantity of RNA for subsequent gene expression study by real-time RT-PCR. The gene expression of VEGF, a major tumor angiogenic factor, was tested in microdissected HNSCC and compared with uninvolved normal mucosal controls. A greater than seven-fold increase of VEGF expression in tumor specimens versus mucosal controls was observed. CONCLUSIONS: LCM is a novel sample conserving technique that allows the precise selection of tumor cells from a heterogeneous architecture. The combination of LCM and real-time RT-PCR appears particularly efficacious for studying HNSCC molecular pathogenesis and identifying tissue-specific biomarkers.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias de Cabeza y Cuello/genética , Rayos Láser , Microdisección , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Biopsia con Aguja , Carcinoma de Células Escamosas/patología , Estudios de Cohortes , Femenino , Secciones por Congelación , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/patología , Humanos , Inmunohistoquímica , Masculino , Probabilidad , ARN Neoplásico/análisis , Sensibilidad y Especificidad , Factor A de Crecimiento Endotelial Vascular/análisis
20.
J Neurosci ; 24(32): 7174-85, 2004 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-15306651

RESUMEN

Oxytocin- and vasopressin-producing magnocellular neurons (MCNs) of the hypothalamo-neurohypophysial system are the only neuronal phenotypes present in the rat supraoptic nucleus (SON). Laser microdissection of the SON, extraction and T7-based amplification of its RNAs, and analysis of the resulting cDNAs by hybridization on a 35, 319 element DNA microarray have provided a detailed composite view of the gene expression profile of the MCNs. The genes expressed in the SON were compared with those expressed in a reference tissue consisting of total hypothalamus, and this "expression ratio" indicated which genes were preferentially expressed in the SON. Of the 26,000 unique genes on the array, 1385 were found to be expressed in the SON at levels more than two times greater than in the hypothalamus as a whole. Of these, 123 were expressed > or =3.4-fold higher in the SON versus hypothalamus. Most of these preferentially expressed genes were not previously known to be expressed in the MCNs. Quantitative and double-label in situ hybridization histochemistry was used selectively to confirm a number of these microarray observations and to evaluate the osmotic regulation and cell-specific expression of these genes, respectively.


Asunto(s)
Perfilación de la Expresión Génica , Hipotálamo Anterior/metabolismo , Neuronas/metabolismo , Animales , Regulación de la Expresión Génica , Hipotálamo Anterior/citología , Hibridación in Situ , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ósmosis , Oxitocina/metabolismo , ARN/biosíntesis , Ratas , Ratas Sprague-Dawley , Vasopresinas/metabolismo
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