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1.
Am J Perinatol ; 35(13): 1331-1338, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29807371

RESUMEN

BACKGROUND: We previously showed, in a single-center study, that early heart rate (HR) characteristics predicted later adverse outcomes in very low birth weight (VLBW) infants. We sought to improve predictive models by adding oxygenation data and testing in a second neonatal intensive care unit (NICU). METHODS: HR and oxygen saturation (SpO2) from the first 12 hours and first 7 days after birth were analyzed for 778 VLBW infants at two NICUs. Using multivariate logistic regression, clinical predictive scores were developed for death, severe intraventricular hemorrhage (sIVH), bronchopulmonary dysplasia (BPD), treated retinopathy of prematurity (tROP), late-onset septicemia (LOS), and necrotizing enterocolitis (NEC). Ten HR-SpO2 measures were analyzed, with first 12 hours data used for predicting death or sIVH and first 7 days for the other outcomes. HR-SpO2 models were combined with clinical models to develop a pulse oximetry predictive score (POPS). Net reclassification improvement (NRI) compared performance of POPS with the clinical predictive score. RESULTS: Models using clinical or pulse oximetry variables alone performed well for each outcome. POPS performed better than clinical variables for predicting death, sIVH, and BPD (NRI > 0.5, p < 0.01), but not tROP, LOS, or NEC. CONCLUSION: Analysis of early HR-SpO2 characteristics adds to clinical risk factors to predict later adverse outcomes in VLBW infants.


Asunto(s)
Enfermedades del Prematuro , Oximetría , Diagnóstico Precoz , Femenino , Edad Gestacional , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Enfermedades del Prematuro/diagnóstico , Enfermedades del Prematuro/mortalidad , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Masculino , Oximetría/métodos , Oximetría/estadística & datos numéricos , Valor Predictivo de las Pruebas , Medición de Riesgo/métodos , Estados Unidos/epidemiología
2.
Chromosome Res ; 21(2): 101-6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23580138

RESUMEN

The first centromeric protein identified in any species was CENP-A, a divergent member of the histone H3 family that was recognised by autoantibodies from patients with scleroderma-spectrum disease. It has recently been suggested to rename this protein CenH3. Here, we argue that the original name should be maintained both because it is the basis of a long established nomenclature for centromere proteins and because it avoids confusion due to the presence of canonical histone H3 at centromeres.


Asunto(s)
Autoantígenos/genética , Proteínas Cromosómicas no Histona/genética , Histonas/genética , Autoantígenos/metabolismo , Centrómero , Proteína A Centromérica , Proteínas Cromosómicas no Histona/metabolismo , Histonas/metabolismo , Humanos , Cinetocoros , Esclerodermia Sistémica/genética , Terminología como Asunto
3.
J Appl Microbiol ; 115(3): 774-85, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23773226

RESUMEN

AIMS: The objective of this study was to determine whether varying levels of urbanization influence the dominant bacterial species of mildly resistant (0·03 mmol l(-1) tetracycline) and highly resistant (0·06 mmol l(-1) tetracycline) bacteria in sediment and water. Also, the level of urbanization was further evaluated to determine whether the diversity of tetracycline resistance genes present in the isolates and the capability of transferring their resistance were influenced. METHODS AND RESULTS: Sediment and water samples collected from five sampling sites were plated in triplicate on nutrient agar plates with a mild dose (0·03 mmol l(-1) ) and a high dose (0·06 mmol l(-1) ) of tetracycline. Five colonies from each plate plus an additional five from each triplicate group were randomly selected and isolated on nutrient agar containing 0·03 mmol l(-1) tetracycline (400 isolates). The isolates were identified by 16S rRNA gene sequencing and comparison to GenBank using blast. The isolates were also screened for 15 tetracycline resistance genes using a multiplex PCR assay and their ability to transfer resistance through conjugation experiments using a kanamycin-resistant Escherichia. coli K-12 strain labelled with a green fluorescent protein gene. Results from this study indicate that the dominant resistant organisms in this watershed are Acinetobacter spp., Chryseobacterium spp., Serratia spp., Pseudomonas spp., Aeromonas spp. and E. coli. All of these organisms are Gram negative and are closely related to pathogenic species. A majority of the isolates (66%) were capable of transferring their resistance, and there was a greater incidence of tet resistance transfer with increasing urbanization. Also, it was determined that the dominant resistance genes in the watershed are tet(W) and tet(A). CONCLUSION: Urbanization significantly affected dominant tetracycline-resistant bacteria species, but did not affect dominant resistance genes. There was correlation between increased urbanization with an increase in the ability to transfer tetracycline resistance. This indicates that urban areas may select for bacterial species that are capable of transferring resistance. SIGNIFICANCE AND IMPACT OF STUDY: These results indicate that urbanization influences the occurrence of tetracycline-resistant bacteria and the potential for transfer of resistance genes.


Asunto(s)
Bacterias/aislamiento & purificación , Genes Bacterianos , Resistencia a la Tetraciclina/genética , Acinetobacter/efectos de los fármacos , Acinetobacter/genética , Aeromonas/efectos de los fármacos , Aeromonas/genética , Bacterias/efectos de los fármacos , Bacterias/genética , Clima , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Sedimentos Geológicos/microbiología , Pseudomonas/efectos de los fármacos , Pseudomonas/genética , Urbanización , Microbiología del Agua
4.
Neurogastroenterol Motil ; 35(5): e14548, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36942766

RESUMEN

BACKGROUND: Gulf War Illness (GWI) is a chronic, multi-symptom disorder affecting 25%-32% of Gulf War veterans. Veterans with GWI disproportionately suffer from gastrointestinal (GI) disorders. Given the increasing evidence supporting a gut-brain axis, we explore the relationship between post-traumatic stress disorder (PTSD), GWI, and self-reported GI disorders among GW veterans. METHODS: Veterans from the Gulf War Era Cohort and Biorepository responded to a mail-based survey (N = 1058). They were stratified by GWI (Centers for Disease Control definition) and PTSD status. This yielded three groups: GWI-, GWI+/PTSD-, and GWI+/PTSD+. Multivariable logistic regression adjusting for demographic and military characteristics examined associations between GWI/PTSD groups and GI disorders. Results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI). KEY RESULTS: The most frequently reported GI disorders were irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and colon polyps (CP). The GWI+/PTSD+ group had a higher odds of these disorders than the GWI+/PTSD- group (aORIBS  = 3.12, 95% CI: 1.93-5.05; aORGERD  = 2.04, 95% CI: 1.44-2.90; aORCP  = 1.85, 95% CI: 1.23-2.80), which had a higher odds of these disorders than the GWI- group (aORIBS  = 4.38, 95% CI: 1.55-12.36; aORGERD  = 2.51 95% CI: 1.63-3.87; aORCP  = 2.57, 95% CI: 1.53-4.32). CONCLUSIONS & INFERENCES: GW veterans with GWI and PTSD have significantly higher odds of specific self-reported GI disorders than the other groups. Given the known bidirectional influences of the gut and brain, these veterans may benefit from a holistic healthcare approach that considers biopsychosocial contributors to the assessment and management of disease.


Asunto(s)
Reflujo Gastroesofágico , Enfermedades Gastrointestinales , Síndrome del Colon Irritable , Síndrome del Golfo Pérsico , Trastornos por Estrés Postraumático , Veteranos , Humanos , Veteranos/psicología , Autoinforme , Guerra del Golfo
5.
J Neonatal Perinatal Med ; 15(1): 155-163, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33967061

RESUMEN

BACKGROUND: Very low birth weight (VLBW) infants must achieve several maturational milestones to be discharged home from the NICU. OBJECTIVE: Describe the timing of maturational milestones in VLBW infants and the impact of clinical variables and milestone achievement on postmenstrual age (PMA) at discharge. METHODS: For VLBW infants without severe lung disease discharged home from a level IV NICU, we assessed PMA at the achievement of thermoregulation, cardiorespiratory stability, feeding, and discharge. RESULTS: In 400 infants (median GA 28.4 weeks), lower birth weight, white race, and having multiple comorbidities of prematurity predicted later discharge PMA. The most common milestone sequence was CPAP discontinuation, caffeine discontinuation, thermoregulation, apnea resolution, and full oral feeds. PMA at apnea resolution and full oral feeds correlated highly with discharge PMA. CONCLUSIONS: In a single-center VLBW cohort, comorbidities of prematurity impacted the timing of NICU discharge through delay in oral feeding and cardiorespiratory stability.


Asunto(s)
Enfermedades del Prematuro , Recién Nacido de muy Bajo Peso , Apnea , Peso al Nacer , Humanos , Lactante , Recién Nacido , Alta del Paciente
6.
J Neonatal Perinatal Med ; 14(2): 269-276, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33136069

RESUMEN

BACKGROUND: Increased understanding of characteristics of urinary tract infection (UTI) among very low birthweight infants (VLBW) might lead to improvement in detection and treatment. Continuous monitoring for abnormal heart rate characteristics (HRC) could provide early warning of UTIs. OBJECTIVE: Describe the characteristics of UTI, including HRC, in VLBW infants. METHODS: We reviewed records of VLBW infants admitted from 2005-2010 at two academic centers participating in a randomized clinical trial of HRC monitoring. Results of all urine cultures, renal ultrasounds (RUS), and voiding cystourethrograms (VCUG) were assessed. Change in the HRC index was analyzed before and after UTI. RESULTS: Of 823 VLBW infants (27.7±2.9 weeks GA, 53% male), 378 had > / = 1 urine culture obtained. A UTI (≥10,000 CFU and >five days of antibiotics) was diagnosed in 80 infants, (10% prevalence, mean GA 25.8±2.0 weeks, 76% male). Prophylactic antibiotics were administered to 29 (36%) infants after UTI, of whom four (14%) had another UTI. Recurrent UTI also occurred in 7/51 (14%) of infants not on uroprophylaxis after their first UTI. RUS was performed after UTI in 78%, and hydronephrosis and other major anomalies were found in 19%. A VCUG was performed in 48% of infants and 18% demonstrated vesicoureteral reflux (VUR). The mean HRC rose and fell significantly in the two days before and after diagnosis of UTI. CONCLUSIONS: UTI was diagnosed in 10% of VLBW infants, and the HRC index increased prior to diagnosis, suggesting that continuous HRC monitoring in the NICU might allow earlier diagnosis and treatment of UTI.


Asunto(s)
Frecuencia Cardíaca , Recién Nacido de muy Bajo Peso , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/tratamiento farmacológico , Humanos , Lactante , Masculino , Estudios Retrospectivos , Factores de Tiempo , Ultrasonografía
7.
J Neonatal Perinatal Med ; 14(4): 553-561, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33523025

RESUMEN

BACKGROUND: In premature infants, clinical changes frequently occur due to sepsis or non-infectious conditions, and distinguishing between these is challenging. Baseline risk factors, vital signs, and clinical signs guide decisions to culture and start antibiotics. We sought to compare heart rate (HR) and oxygenation (SpO2) patterns as well as baseline variables and clinical signs prompting sepsis work-ups ultimately determined to be late-onset sepsis (LOS) and sepsis ruled out (SRO). METHODS: At three NICUs, we reviewed records of very low birth weight (VLBW) infants around their first sepsis work-up diagnosed as LOS or SRO. Clinical signs prompting the evaluation were determined from clinician documentation. HR-SpO2 data, when available, were analyzed for mean, standard deviation, skewness, kurtosis, and cross-correlation. We used LASSO and logistic regression to assess variable importance and associations with LOS compared to SRO. RESULTS: We analyzed sepsis work-ups in 408 infants (173 LOS, 235 SRO). Compared to infants with SRO, those with LOS were of lower GA and BW, and more likely to have a central catheter and mechanical ventilation. Clinical signs cited more often in LOS included hypotension, acidosis, abdominal distension, lethargy, oliguria, and abnormal CBC or CRP(p < 0.05). HR-SpO2 data were available in 266 events. Cross-correlation HR-SpO2 before the event was associated with LOS after adjusting for GA, BW, and postnatal age. A model combining baseline, clinical and HR-SpO2 variables had AUC 0.821. CONCLUSION: In VLBW infants at 3-NICUs, we describe the baseline, clinical, and HR-SpO2 variables associated with LOS versus SRO.


Asunto(s)
Saturación de Oxígeno , Sepsis , Humanos , Lactante , Recién Nacido , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal , Factores de Riesgo , Sepsis/diagnóstico , Signos Vitales
8.
Curr Top Microbiol Immunol ; 314: 165-93, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17593661

RESUMEN

Populations of unconventional T lymphocytes that express alpha beta T cell antigen receptors (TCRs) have been characterized, including T cells reactive to glycolipids presented by CD1 molecules. The CD1 molecules have a structure broadly similar to major histocompatibility complex (MHC) class I and class II proteins, but because the antigens CD 1 presents are so different from peptides, it is possible that glycolipid reactive TCRs have properties that distinguish them from TCRs expressed by conventional T cells. Consistent with this possibility, CD1-reactive T cells have an unrestrained pattern of co-receptor expression, as they include CD4+, CD8+, and double-negative cells. Furthermore, unlike peptide-reactive T cells, there are populations of glycolipid-reactive T cells with invariant alpha chain TCRs that are conserved across species. There are also glycolipid reactive populations with more variable TCRs, however, suggesting that it may be difficult to make categorical generalizations about glycolipid reactive TCRs. Among the glycolipid reactive TCRs, the invariant TCR expressed by CD1d reactive NKT cells has been by far the most thoroughly studied, and in this article we emphasize the unique features of this antigen recognition system, including repertoire formation, fine specificity, TCR affinity, and TCR structure.


Asunto(s)
Antígenos CD1/metabolismo , Glucolípidos/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Animales , Antígenos CD1/química , Glucolípidos/química , Humanos , Células Asesinas Naturales/inmunología , Ratones , Receptores de Antígenos de Linfocitos T alfa-beta/química , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Linfocitos T/inmunología
10.
Curr Biol ; 7(11): 901-4, 1997 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9382805

RESUMEN

The trilaminar kinetochore directs the segregation of chromosomes in mitosis and meiosis. Despite its importance, the molecular architecture of this structure remains poorly understood [1]. The best known component of the kinetochore plates is CENP-C, a protein that is required for kinetochore assembly [2], but whose molecular role in kinetochore structure and function is unknown. Here we have raised for the first time monospecific antisera to CENP-A [3], a 17 kD centromere-specific histone variant that is 62% identical to the carboxy-terminal domain of histone H3 [4,5] and that resembles the yeast centromeric component CSE4 [6]. We have found by simultaneous immunofluorescence with centromere antigens of known ultrastructural location that CENP-A is concentrated in the region of the inner kinetochore plate at active centromeres. Because CENP-A was previously shown to co-purify with nucleosomes [7], our data suggest a specific nucleosomal substructure for the kinetochore. In human cells, these kinetochore-specific nucleosomes are enriched in alpha-satellite DNA [8]. However, the association of CENP-A with neocentromeres lacking detectable alpha-satellite DNA, and the lack of CENP-A association with alpha-satellite-rich inactive centromeres of dicentric chromosomes together suggest that CENP-A association with kinetochores is unlikely to be determined solely by DNA sequence recognition. We speculate that CENP-A binding could be a consequence of epigenetic tagging of mammalian centromeres.


Asunto(s)
Centrómero/metabolismo , Proteínas Cromosómicas no Histona/inmunología , Proteínas Cromosómicas no Histona/metabolismo , Cinetocoros/metabolismo , Nucleosomas/metabolismo , Secuencia de Aminoácidos , Autoanticuerpos/metabolismo , Autoantígenos/química , Autoantígenos/inmunología , Autoantígenos/metabolismo , Centrómero/química , Proteína A Centromérica , Proteínas Cromosómicas no Histona/química , Células HeLa , Humanos , Cinetocoros/química , Datos de Secuencia Molecular , Nucleosomas/química
11.
Appl Spectrosc ; 60(9): 994-1003, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17002824

RESUMEN

This investigation utilizes surface plasmon resonance (SPR) spectroscopy to detect and quantify human epidermal growth factor receptor 2 (HER-2), an oncogene product that is over-expressed in some aggressive forms of breast cancer. Specifically, the HER-2 trans-membrane protein p185 and its extra cellular fragment p105 are analytes targeted in this work by using a gold-based biosensor slide on which an anti-HER-2 antibody has been immobilized by attachment to Protein G that is fixed to the gold film. A detection limit of > or =11 ng/mL for p185 resulted when trastuzumab was used as the anti-HER-2 antibody on the biosensor slide. Experiments with semi-purified p105 revealed that it binds weakly and reversibly to trastuzumab, therefore complicating its detection and quantification. Results of studies that reacted a 13-amino-acid peptide (PP13) from the HER-2 kinase domain with its specific antibody were critically different than p185 and p105 studies. Spectral analysis of the reflectivity at constant bulk buffer refractive index revealed a progressive negative SPR shift over time. A negative shift suggests that a loss of protein mass from the anti-PP13 antibody-Protein G biosensor is occurring. Several possibilities that may explain these negative SPR shifts are discussed.


Asunto(s)
Receptor ErbB-2/análisis , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales Humanizados , Técnicas Biosensibles , Línea Celular Tumoral , Oro , Humanos , Inmunoensayo , Proteínas del Tejido Nervioso/química , Oligopéptidos/química , Unión Proteica , Estructura Terciaria de Proteína , Receptor ErbB-2/inmunología , Receptor ErbB-2/aislamiento & purificación , Proteínas Recombinantes/química , Resonancia por Plasmón de Superficie , Trastuzumab
12.
Lupus Sci Med ; 3(1): e000146, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27099766

RESUMEN

OBJECTIVES: To evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of single-dose and multiple-dose administration of AMG 557, a human anti-inducible T cell co-stimulator ligand (ICOSL) monoclonal antibody, in subjects with systemic lupus erythematosus (SLE). METHODS: Patients with mild, stable SLE (n=112) were enrolled in two clinical trials to evaluate the effects of single (1.8-210 mg subcutaneous or 18 mg intravenous) and multiple (6 -210 mg subcutaneous every other week (Q2W)×7) doses of AMG 557. Subjects received two 1 mg intradermal injections 28 days apart of keyhole limpet haemocyanin (KLH), a neoantigen, to assess PD effects of AMG 557. Safety, PK, target occupancy, anti-KLH antibody responses, lymphocyte subset analyses and SLE-associated biomarkers and clinical outcomes were assessed. RESULTS: AMG 557 demonstrated an acceptable safety profile. The PK properties were consistent with an antibody directed against a cell surface target, with non-linear PK observed at lower concentrations and linear PK at higher concentrations. Target occupancy by AMG 557 was dose dependent and reversible, and maximal occupancy was achieved in the setting of this trial. Anti-AMG 557 antibodies were observed, but none were neutralising and without impact on drug levels. A significant reduction in the anti-KLH IgG response was observed with AMG 557 administration without discernible changes in the anti-KLH IgM response or on the overall IgG levels. No discernible changes were seen in lymphocyte subsets or in SLE-related biomarkers and clinical measures. CONCLUSIONS: The selective reduction in anti-KLH IgG demonstrates a PD effect of AMG 557 in subjects with SLE consistent with the biology of the ICOS pathway and supports further studies of AMG 557 as a potential therapeutic for autoimmune diseases. TRIAL REGISTRATION NUMBERS: NCT02391259 and NCT00774943.

13.
J Clin Oncol ; 11(10): 1888-93, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8410114

RESUMEN

PURPOSE: A prospectively randomized trial was performed to determine whether the combination of fluorouracil (FU) plus leucovorin (FU-LV) administered orally is more effective than equitoxic FU for patients with metastatic colorectal cancer. PATIENTS AND METHODS: A double-blind, placebo-controlled trial design was used to eliminate observer bias. An escalating FU dosing schedule was used to achieve equal toxicity. End points were response, time to treatment failure (TTF), and eight quality-of-life (QL) parameters. A crossover arm allowed FU-treated patients to receive FU-LV combination treatment after treatment failure. RESULTS: Response rate was 32% for FU-LV versus 23% for FU (P = .15). Median TTF was 22 versus 16 weeks (P = .27). Median survival time was 44 versus 54 weeks (P = .26). QL was the same for both treatments, except for days of hospitalization, which was greater for FU-LV (P < .001). Toxicities were similar to those previously reported for FU-LV and FU alone. CONCLUSION: Oral LV-FU produces the same efficacy and toxicity pattern as has been reported for intravenous LV-FU. When FU-LV is compared with equitoxic doses of FU, there is no difference in patient outcome. These results suggest that patients with advanced disease should receive FU at doses adequate to produce toxicity.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Fluorouracilo/uso terapéutico , Leucovorina/uso terapéutico , Adenocarcinoma/secundario , Anciano , Neoplasias Colorrectales/patología , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Análisis de Supervivencia , Resultado del Tratamiento
14.
Am J Med Genet ; 47(2): 223-30, 1993 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8213910

RESUMEN

Fluorescence in situ hybridization (FISH) using chromosome-specific DNA libraries as painting probes was applied in the analysis of six subtle, balanced chromosome rearrangements. Both fresh and older slides, some of which had been previously G-banded, were used to determine if FISH could identify unambiguously very small amounts of translocated material. Our results indicate that this procedure can clearly and precisely distinguish the specific components of extremely subtle translocations, in different cell types, such as leukocytes, aminocytes, and chorionic villus, and irregardless of preparation age. This ability makes FISH a valuable tool in clinical cytogenetics for the confirmation of preliminary G-banded karyotypes.


Asunto(s)
Hibridación in Situ/métodos , Diagnóstico Prenatal/métodos , Translocación Genética , Cromosomas Humanos Par 1 , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 17 , Cromosomas Humanos Par 18 , Cromosomas Humanos Par 22 , Cromosomas Humanos Par 4 , Cromosomas Humanos Par 7 , Cromosomas Humanos Par 8 , Cromosomas Humanos Par 9 , Sondas de ADN , Femenino , Biblioteca de Genes , Humanos , Masculino , Embarazo , Sensibilidad y Especificidad
15.
Am J Med Genet ; 75(1): 45-51, 1998 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-9450856

RESUMEN

Cytogenetic studies of 2 sisters with mild microcephaly, growth deficiency, and mild errors of morphogenesis demonstrated a unique combination of multiple trisomies, most often involving chromosomes 8 and 18 either together as sole trisomies or in combination with other chromosomes. Since neither sib has phenotypic anomalies associated with trisomy 8 or 18 mosaicism, the trisomies likely did not occur during embryogenesis, but later possibly due to a predisposition for mitotic instability. To determine if the observed chromosome instability may be related to centromere function, metaphase cells were characterized by immunofluorescence of the centromere protein, CENP-E. Hybridization of CENP-E antibodies, in combination with in situ hybridization of a chromosome 8 or 18 alpha-satellite probe, showed hybridization to chromosomes 8 and 18 in both normal and aneuploid cells from each patient. These data indicate that the chromosomes in each child contain functional and active centromeres. The clinical and cytogenetic findings in these 2 individuals are compared with 7 other previously reported individuals, each of whom have similar findings. Together, these studies support the notion that a recessive mitotic mutant may be responsible for the chromosomal mosaicism and for the resulting clinical phenotype.


Asunto(s)
Proteínas Cromosómicas no Histona/análisis , Fenotipo , Ploidias , Centrómero/genética , Preescolar , Cromosomas Humanos Par 18 , Cromosomas Humanos Par 8 , Citogenética , Femenino , Genotipo , Humanos , Trisomía/patología
16.
Cancer Genet Cytogenet ; 82(2): 93-9, 1995 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-7664251

RESUMEN

Identification of complex chromosomal rearrangements can be difficult, due either to the limited number and sometimes poor quality of metaphases in bone marrow preparations or to the nature of the rearrangements. Fluorescence in situ hybridization (FISH) using chromosome-specific DNA libraries in conjunction with a cosmid probe for the c-ABL oncogene was performed to substantiate the preliminary G-banded karyotypes of six patients with chronic myelogenous leukemia (CML). Our results indicate that FISH is sufficiently sensitive to detect complex and subtle rearrangements, even in bone marrow preparations with suboptimal metaphases, and can provide valuable corroborative information.


Asunto(s)
Aberraciones Cromosómicas , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Médula Ósea/ultraestructura , Sondas de ADN , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Cromosoma Filadelfia
17.
Environ Mol Mutagen ; 28(3): 182-91, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8908179

RESUMEN

The centromere, recognized cytologically as the primary constriction, is essential for chromosomal attachment to the spindle and for proper segregation of mitotic and meiotic chromosomes. Considerable progress has been made in identifying both DNA and protein components of the centromere and kinetochore complex in mammalian chromosomes, including definition of specific motor proteins with demonstrable functions in chromosome movement. Searches for possible environmental influences on chromosome disjunction might logically be based on known components of the segregation apparatus, both intrinsic and extrinsic to the chromosomes themselves. This article reviews available information on both DNA and protein components of the centromere of mammalian, particularly human, chromosomes and summarizes our current understanding of their role(s) in facilitating normal chromosome behavior in mitosis and meiosis.


Asunto(s)
Autoantígenos , Centrómero , Proteínas Cromosómicas no Histona/fisiología , Cromosomas Humanos , Proteínas de Unión al ADN , Animales , Proteína A Centromérica , Proteína B del Centrómero , ADN Satélite/química , ADN Satélite/genética , ADN Satélite/metabolismo , Humanos , Cinetocoros , Mamíferos/genética
18.
Pharmacotherapy ; 15(5): 600-7, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8570432

RESUMEN

We compared health-related quality of life (HQL) measures in 210 patients with metastatic colorectal cancer who were receiving equitoxic regimens of weekly 5-fluorouracil (5-FU) plus leucovorin (LV) or 5-FU alone in a multicenter, placebo-controlled, double-blind, randomized trial. The HQL was assessed during the first 120 days of treatment by the patient-generated functional living index-cancer (FLIC) questionnaire. Also assessed were clinician-generated measures to evaluate physical functioning and suffering: Karnofsky performance status (KPS), body weight, disease symptoms, and hospitalization. No significant difference was detected between treatment groups in HQL or in any measurement of efficacy or toxicity. The number of patients hospitalized was similar in both groups, 35 patients receiving 5-FU-LV, 32 receiving 5-FU-placebo, but those receiving 5-FU-LV were hospitalized longer (450 vs 315 total days). The KPS improved or stabilized in 23% and 37% of patients, respectively. Overall, FLIC scores significantly improved in 27% or remained stable in 62% of all patients; disease symptoms improved in 19-49%; a weight increase of 2 kg or more occurred in 27%. A change in FLIC was not associated with tumor response or improvement in pain, but a decline in FLIC was associated with improved survival. An improvement in KPS or weight was associated with tumor response and strongly correlated with survival. Improvement of pain was associated with a stable or increase in weight, and worsening of pain correlated with lack of tumor response.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Calidad de Vida , Neoplasias del Recto/tratamiento farmacológico , Adenocarcinoma/secundario , Adulto , Anciano , Antimetabolitos Antineoplásicos/administración & dosificación , Neoplasias del Colon/patología , Método Doble Ciego , Femenino , Fluorouracilo/administración & dosificación , Hospitalización , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Dolor/prevención & control , Neoplasias del Recto/patología , Encuestas y Cuestionarios
20.
Hum Mol Genet ; 4(12): 2189-97, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8634687

RESUMEN

Robertsonian translocations are the most common structural dicentric rearrangements in humans. The stability of these dicentrics is attributed to the inactivation of one centromere by mechanisms which are currently unknown. The presence and amounts of centromeric proteins (CENPs) differ between the centromeres of the few dicentrics which have been studied, providing a limited understanding of the protein components necessary for centromeric function. However, CENP-C previously has been observed only at the active centromeres in two dicentric chromosomes. In the present investigation, the presence and localizations of several centromeric antigens, CENP-B, -C and -E, have been determined in 12 dicentric Robertsonian translocations. Each translocation was studied initially using in situ hybridization with alpha-satellite DNA probes to determine the active centromere. Subsequent immunofluorescence of monoclonal and polyclonal antibodies generated to various centromeric antigens demonstrated that the protein composition differs at the two centromeres of these dicentric translocations. While CENP-B was present at both active and inactive centromeres, CENP-C and -E were located at active centromeres only in the majority of translocations. These results confirm previous observations of CENP-C at active centromeres and provide the first evidence that CENP-E correlates with active centromeres as well, demonstrating that at least two specific centromeric proteins are required for human centromeric function.


Asunto(s)
Centrómero/inmunología , Proteínas Cromosómicas no Histona/fisiología , Proteínas de Unión al ADN , Translocación Genética , Autoantígenos/inmunología , Autoantígenos/fisiología , Síndrome CREST/inmunología , Centrómero/fisiología , Proteína B del Centrómero , Proteínas Cromosómicas no Histona/inmunología , Cromosomas Humanos Par 13 , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 15 , Cromosomas Humanos Par 21 , Humanos , Hibridación Fluorescente in Situ , Microscopía Fluorescente
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