RESUMEN
BACKGROUND: Echocardiography is increasingly becoming an integrated tool for circulatory evaluation in the intensive care unit and the operating room. Therefore, it is imperative to know the reproducibility of measurements obtained by echocardiography. In this study, a comparison of cardiac output (CO) measurements obtained with transesophageal echocardiography (TEE) and pulmonary artery catheter (PAC) thermodilution (TD) was carried out to test the precision, accuracy and trending ability of CO measurements obtained with TEE. METHODS: Twenty-five patients completed the study. Each patient was placed in the following successive positions: supine, head-down tilt, head-up tilt, supine, supine with phenylephrine administration, pace heart rate 80 beats per minute (bpm), pace heart rate 110 bpm. TEE CO and PAC CO were measured simultaneously. The agreement was analysed by Bland-Altman plots, and to assess trending ability, a polar plot was constructed. RESULTS: Both methods showed an acceptable precision 8% (PAC TD) and 16% (TEE). In comparison with PAC TD, the TEE was associated with a bias of -0.22 l/minute [95% confidence interval: -0.54; 0.10], wide limits of agreement (-1.73 l/minute; 1.29 l/minute), a percentage error of 38.6% and a trending ability with a radial degree of 53.6°, corresponding to a poor trending ability. CONCLUSION: In comparison, CO measurements obtained with TEE and PAC TD had wide limits of agreement, a larger percentage error than would be expected from the precision of the two methods, and a poor trending ability. Thus, TEE is not interchangeable with PAC TD for measuring CO.
Asunto(s)
Gasto Cardíaco/fisiología , Ecocardiografía Transesofágica/métodos , Arteria Pulmonar/fisiología , Termodilución/métodos , Anciano , Anciano de 80 o más Años , Algoritmos , Anestesia General , Puente de Arteria Coronaria , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio , Insuficiencia Multiorgánica/etiología , Insuficiencia Multiorgánica/mortalidad , Fenilefrina/farmacología , Postura/fisiología , Reproducibilidad de los Resultados , Síndrome de Dificultad Respiratoria/diagnóstico , Síndrome de Dificultad Respiratoria/fisiopatología , Vasoconstrictores/farmacologíaRESUMEN
BACKGROUND: Minimally invasive monitoring systems of central haemodynamics are gaining increasing popularity. The present study investigated the precision of the endotracheal cardiac output monitor (ECOM) system and its agreement with pulmonary artery catheter thermodilution (PAC TD) for measuring cardiac output (CO) during steady state and with induced haemodynamic changes in patients scheduled for elective cardiac surgery. METHODS: Twenty-five patients were enrolled. After induction of anaesthesia, endotracheal intubation using a dedicated ECOM tube, and insertion of the pulmonary artery catheter (PAC), the patient was placed in the following successive positions: (a) supine, (b) head-down tilt, (c) head-up tilt, (d) supine, (e) supine with phenylephrine administration. CO was measured simultaneously using the ECOM and the PAC. RESULTS: Both methods showed an equally good precision < 10%. Compared to PAC TD, the ECOM system was associated with a bias in supine position of -0.45 l/min (95% confidence interval: -0.86; -0.05), limits of agreement -2.40 l/min to 1.49 l/min and a percentage error of 41.0%. There was no agreement in trending ability between the two methods, with a concordance rate of 30%, shown in a four-quadrant plot. CONCLUSION: In a direct comparison with PAC TD, the ECOM system did not show an acceptable agreement, with wide limits of agreement, a much larger percentage error than should be expected from the precision of the two methods and a very poor trending ability. Thus, the ECOM does not replace measurements done by thermodilution using a pulmonary artery catheter in cardiac surgery patients.
Asunto(s)
Gasto Cardíaco , Monitoreo Fisiológico/instrumentación , Termodilución/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Spectrograms in medical ultrasound are usually estimated with Welch's method (WM). WM is dependent on an observation window (OW) of up to 256 emissions per estimate to achieve sufficient spectral resolution and contrast. Two adaptive filterbank methods have been suggested to reduce the OW: Blood spectral Power Capon (BPC) and the Blood Amplitude and Phase EStimation method (BAPES). Ten volunteers were scanned over the carotid artery. From each data set, 28 spectrograms were produced by combining four approaches (WM with a Hanning window (W.HAN), WM with a boxcar window (W.BOX), BPC and BAPES) and seven OWs (128, 64, 32, 16, 8, 4, 2). The full-width-at-half-maximum (FWHM) and the ratio between main and side-lobe levels were calculated at end-diastole for each spectrogram. Furthermore, all 280 spectrograms were randomized and presented to nine radiologists for visual evaluation: useful/not useful. BAPES and BPC compared to WM had better resolution (lower FWHM) for all OW<128 while only BAPES compared to WM had improved contrast (higher ratio). According to the scores given by the radiologists, BAPES, BPC and W.HAN performed equally well (p>0.05) at OW 128 and 64, while W.BOX scored less (p<0.05). At OW 32, BAPES and BPC performed better than WM (p<0.0001) and BAPES was significantly superior to BPC at OW 16 (p=0.0002) and 8 (p<0.0001). BPC at OW 32 performed as well as BPC at OW 128 (p=0.29) and BAPES at OW 16 as BAPES at OW 128 (p=0.55). WM at OW 16 and 8 failed as all four methods at OW 4 and 2. The intra-observer variability tested for three radiologist showed on average good agreement (90%, kappa=0.79) and inter-observer variability showed moderate agreement (78%, kappa=0.56). The results indicated that BPC and BAPES had better resolution and BAPES better contrast than WM, and that OW can be reduced to 32 using BPC and 16 using BAPES without reducing the usefulness of the spectrogram. This could potentially increase the temporal resolution of the spectrogram or the frame-rate of the interleaved B-mode images.
Asunto(s)
Algoritmos , Velocidad del Flujo Sanguíneo/fisiología , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Reología/métodos , Ultrasonografía Doppler/métodos , Adulto , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
PURPOSE: Conventional ultrasound methods for acquiring color flow images of the blood motion are limited by a relatively low frame rate and are restricted to only giving velocity estimates along the ultrasound beam direction. To circumvent these limitations, the Plane Wave Excitation (PWE) method has been proposed. MATERIAL AND METHODS: The PWE method can estimate the 2D vector velocity of the blood with a high frame rate. Vector velocity estimates are acquired by using the following approach: The ultrasound is not focused during the ultrasound transmission, and a full speckle image of the blood can be acquired for each pulse emission. The pulse is a 13 bit Barker code transmitted simultaneously from each transducer element. The 2D vector velocity of the blood is found using 2D speckle tracking between segments in consecutive speckle images. Implemented on the experimental scanner RASMUS and using a 100 CPU linux cluster for post processing, PWE can achieve a frame of 100 Hz where one vector velocity sequence of approximately 3 sec, takes 10 h to store and 48 h to process. In this paper a case study is presented of in-vivo vector velocity estimates in different complex vessel geometries. RESULTS: The flow patterns of six bifurcations and two veins were investigated. It was shown: 1. that a stable vortex in the carotid bulb was present opposed to other examined bifurcations, 2. that retrograde flow was present in the superficial branch of the femoral artery during diastole, 3. that retrograde flow was present in the subclavian artery and antegrade in the common carotid artery during diastole, 4. that vortices were formed in the sinus pockets behind the venous valves in both antegrade and retrograde flow, and 5. that secondary flow was present in various vessels. CONCLUSION: Using a fast vector velocity ultrasound method, in-vivo scans have been recorded where complex flow patterns were visualized in greater detail than previously visualized by conventional color flow imaging techniques.
Asunto(s)
Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Común/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Velocidad del Flujo Sanguíneo , Tronco Braquiocefálico/diagnóstico por imagen , Venas Cerebrales/diagnóstico por imagen , Diástole , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Venas Yugulares/diagnóstico por imagen , Vena Safena/diagnóstico por imagen , Sensibilidad y EspecificidadRESUMEN
The objective of this paper is to validate angle independent vector velocity methods for blood velocity estimation. Conventional Doppler ultrasound (US) only estimates the blood velocity along the US beam direction where the estimate is angle corrected assuming laminar flow parallel to vessel boundaries. This results in incorrect blood velocity estimates, when angle of insonation approaches 90 degrees or when blood flow is non-laminar. Three angle independent vector velocity methods are evaluated in this paper: directional beamforming (DB), synthetic aperture flow imaging (STA) and transverse oscillation (TO). The performances of the three methods were investigated by measuring the stroke volume in the right common carotid artery of 11 healthy volunteers with magnetic resonance phase contrast angiography (MRA) as reference. The correlation with confidence intervals (CI) between the three vector velocity methods and MRA were: DB vs. MRA: R=0.84 (p<0.01, 95% CI: 0.49-0.96); STA vs. MRA: R=0.71 (p<0.05, 95% CI: 0.19-0.92) and TO vs. MRA: R=0.91 (p<0.01, 95% CI: 0.69-0.98). No significant differences were observed for any of the three comparisons (DB vs. MRA: p=0.65; STA vs. MRA: p=0.24; TO vs. MRA: p=0.36). Bland-Altman plots were additionally constructed, and mean differences with limits of agreements (LoA) for the three comparisons were: DB vs. MRA=0.17 ml (95% CI: -0.61-0.95) with LoA=-2.11-2.44 ml; STA vs. MRA=-0.55 ml (95% CI: -1.54-0.43) with LoA=-3.42-2.32 ml; TO vs. MRA=0.24 ml (95% CI: -0.32-0.81) with LoA=-1.41-1.90 ml. According to the results, reliable volume flow estimates can be obtained with all three methods. The three US vector velocity techniques can yield quantitative insight into flow dynamics and visualize complex flow patterns, which potentially can give the clinician a novel tool for cardiovascular disease assessment.
Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Arteria Carótida Común/fisiología , Angiografía Cerebral/métodos , Circulación Cerebrovascular/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Angiografía por Resonancia Magnética/métodos , Ultrasonografía Doppler/métodos , Algoritmos , Arteria Carótida Común/anatomía & histología , Arteria Carótida Común/diagnóstico por imagen , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
The aim of the present investigation was to study prevalence of low back pain, pelvic girdle pain (PGP) and pelvic floor disorders during pregnancy and after childbirth in elite athletes. A postal questionnaire was sent to all elite athletes who had given birth registered with The Norwegian Olympic Committee and Confederation of Sports (n=40). Eighty age-matched women served as the control group. The response rates were 77.5% and 57.5% in the elite athletes and control groups, respectively. There were no significant differences in the prevalence of low back and PGP, urinary or fecal incontinence among elite athletes and controls at any time point. The prevalence of low back pain without radiation to the leg in elite athletes was 25.8%, 18.5%, 9.7% and 29% the year before pregnancy, during pregnancy, 6 weeks postpartum and at the time of completing the questionnaire, respectively. The prevalence of PGP was 0, 29.6%, 12.9% and 19.4%. Prevalence of stress urinary incontinence was 12.9%, 18.5%, 29% and 35.5%. None of the elite athletes had fecal incontinence at any time point. There were no differences in mode of delivery or birthweight between elite athletes and controls. The elite athletes had a significantly lower body mass index at 6 weeks postpartum and at present compared with the control group.
Asunto(s)
Dolor de la Región Lumbar/epidemiología , Actividad Motora , Diafragma Pélvico/fisiología , Dolor Pélvico/epidemiología , Pelvis/fisiología , Resultado del Embarazo , Deportes/fisiología , Adulto , Estudios de Casos y Controles , Incontinencia Fecal/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/epidemiología , Noruega/epidemiología , Embarazo , Prevalencia , Estudios Retrospectivos , Encuestas y Cuestionarios , Factores de Tiempo , Incontinencia Urinaria/epidemiologíaRESUMEN
OBJECTIVE: To compare two quantitative pilocarpine iontophoresis tests for sweat chloride. DESIGN: Simultaneous right and left arm sweat tests were done with the Gibson/Cooke and the CF quantum technologies. SETTING: Sweat tests were performed in a quality controlled cystic fibrosis (CF) sweat test laboratory by an experienced technologist at the University of Minnesota CF Center. PATIENTS: Patients referred for sweat tests as well as volunteer CF and control subjects (50 CF and 114 'normals') were tested. INTERVENTIONS: Standard procedures were used for the Gibson/Cooke test (GCST). The manufacturer of the CF quantum test (CFQT) provided factory standardized materials. MAIN OUTCOME MEASURES: Sweat chloride concentration, test time, failed tests, sensitivity, specificity, and cost. RESULTS: Duplicate test comparing the CFQT and the GCST revealed good comparability (R2 = 0.9434). Sensitivity and specificity of the two methods are comparable at about 94% and 99% respectively. Rate of failed tests was 1% for the CFQT and 15% for the GCST. The CFQT and the GCST are comparable (R2 = 0.9434). Sensitivity (94%) and specificity (99%) are the same for both tests. CONCLUSIONS: The CFQT method is equal in accuracy and reliability to the more labor-intensive and costly GCST. Advantages of the CFQT are: the small sample size required (three to ten mg), decreased operator dependence, simpler to perform, and requires less equipment. It could be used in a clinic setting to diagnose CF in patients with suggestive symptoms.
Asunto(s)
Cloruros/análisis , Fibrosis Quística/diagnóstico , Juego de Reactivos para Diagnóstico , Sudor/química , Adolescente , Adulto , Anciano , Niño , Preescolar , Humanos , Lactante , Iontoforesis , Persona de Mediana Edad , Pilocarpina/administración & dosificación , Sensibilidad y EspecificidadRESUMEN
Four van Veen grab replicates where collected to sample macrofauna (organism retained on a 500 micron mesh sieve) at four stations in the Gulf of Nicoya, during October 24, 1997, January 16 and April 30, 1998. This information was used to search for any effects of trawling on the benthic fauna. Two stations where located in a trawled area, and two stations where in a protected area. Diversity (H') varied from 2.01 to 3.52 in the trawled area and from 2.13 to 2.78 in the protected area. Diversity was generally higher in the trawled area, and this was in contradiction to what we would have expected from other studies where the trend has been that trawling reduces diversity. Brittlestars and lancelets seemed to be the groups mostly harmed by the trawling, while amphipods where more abundant in trawled areas. The multivariate analyses did not reveal the patterns of faunal change as well as we hoped. This is surely because of our lack of more replicate samples. The multivariate analyses are easily confounded when few sites are analyzed. We have found differences in the type of fauna found in trawled and protected areas and, considering the differences in environmental variables in our stations and our lack of replication, this indicates that there are differences and a larger investigation is in order to reveal its magnitude.
Asunto(s)
Monitoreo del Ambiente , Explotaciones Pesqueras/métodos , Invertebrados/clasificación , Animales , Biodiversidad , Costa Rica , Análisis Multivariante , Densidad de PoblaciónRESUMEN
A candidate tumor suppressor gene, MMAC1/PTEN, located in human chromosome band 10q23, was recently identified based on sequence alterations observed in several glioma, breast, prostate, and kidney tumor specimens or cell lines. To further investigate the mutational profile of this gene in human cancers, we examined a large set of human tumor specimens and cancer cell lines of many types for 10q23 allelic losses and MMAC1 sequence alterations. Loss of heterozygosity (LOH) at the MMAC1 locus was observed in approximately one-half of the samples examined, consistent with the high frequency of 10q allelic loss reported for many cancers. Of 124 tumor specimens exhibiting LOH that have been screened for MMAC1 alterations to date, we have detected variants in 13 (approximately 10%) of these primary tumors; the highest frequency of variants was found in glioblastoma specimens (approximately 23%). Novel alterations identified in this gene include a missense variant in a melanoma sample and a splicing variant and a nonsense mutation in pediatric glioblastomas. Of 76 tumor cell lines prescreened for probable LOH, microsequence alterations of MMAC1 were detected in 12 (approximately 16%) of the lines, including those derived from astrocytoma, leukemia, and melanoma tumors, as well as bladder, breast, lung, prostate, submaxillary gland, and testis carcinomas. In addition, in this set of tumor cell lines, we detected 11 (approximately 14%) homozygous deletions that eliminated coding portions of MMAC1, a class of abnormality not detected by our methods in primary tumors. These data support the occurrence of inactivating MMAC1 alterations in multiple human cancer types. In addition, we report the discovery of a putative pseudogene of MMAC1 localized on chromosome 9.
Asunto(s)
Cromosomas Humanos Par 10 , Mutación , Neoplasias/genética , Monoéster Fosfórico Hidrolasas , Proteínas Tirosina Fosfatasas/genética , Proteínas Supresoras de Tumor , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Niño , Mapeo Cromosómico , Exones , Femenino , Eliminación de Gen , Marcadores Genéticos , Variación Genética , Glioblastoma/genética , Glioblastoma/patología , Glioma/genética , Glioma/patología , Humanos , Intrones , Neoplasias Renales/genética , Neoplasias Renales/patología , Masculino , Neoplasias/patología , Fosfohidrolasa PTEN , Mutación Puntual , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Tirosina Fosfatasas/análisis , Proteínas Tirosina Fosfatasas/biosíntesis , Eliminación de Secuencia , Neoplasias Testiculares/genética , Neoplasias Testiculares/patología , Células Tumorales CultivadasRESUMEN
We addressed experimentally the suggestion by Gally et al. [Gally J. A., Read Montague P., Reeke G. N. Jr and Edelman G. M. (1990) Proc. Natl Acad. Sci. U.S.A. 87, 3547-3551] that nitric oxide may play a role in the use-dependent modification of synaptic efficacy in the developing nervous system. In a preliminary control experiment, we treated rat pups from postnatal day 8 to postnatal day 22 with a nitric oxide synthase blocker (L-nitro-arginine) and compared their growth curves and brain weights to those of saline injected control pubs. No significant differences were found after the 14 days of nitric oxide synthase inhibition. In the subsequent experiment, we inhibited nitric oxide synthesis in rat pups from postnatal day 8 to day 29 and assessed their place learning ability and open field behavior as adults. We found an increased speed of habituation of locomotion in an open field in 5-month-old rats that had been treated postnatally with a nitric oxide synthase blocker. There was no difference between treated and non-treated rats with respect to place learning in a water maze. We conclude that perturbation of nitric oxide production during early postnatal development does not preclude normal learning and memory function in the adult.
Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Conducta Animal/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Nitroarginina/farmacología , Animales , Peso Corporal/efectos de los fármacos , Encéfalo/anatomía & histología , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Óxido Nítrico Sintasa/antagonistas & inhibidores , Ratas , Ratas Wistar , Cloruro de Sodio/farmacologíaRESUMEN
High frequency chest compression (HFCC) appears promising as a form of chest physiotherapy. Studies published by several clinical centers support its efficacy, and further clinical data are expected to become available.
Asunto(s)
Fibrosis Quística/terapia , Drenaje Postural , Enfermedades Pulmonares Obstructivas/terapia , Moco , Terapia Respiratoria , Ensayos Clínicos como Asunto , Trajes Gravitatorios , Humanos , Depuración Mucociliar/fisiologíaRESUMEN
Leukemias are characterized by an idiopathic proliferation of a progenitor cell that is committed to a single cell lineage. However, leukemias with dual-lineage differentiation are being described, especially within the pediatric age group. The authors reviewed 118 cases of adult acute leukemia phenotyped by immunofluorescent flow cytometry; 7 cases demonstrated mixed cell lineage. Immunophenotypically these cases were defined by early B-lymphocyte differentiation (TdT, HLA-DR, and CD19) coexpressed with a myeloid receptor (CD13, CD15, or CD33) on the same leukemic cell. Routine cytochemical evaluation demonstrated punctate positivity of the blasts with naphthol AS-D chloroacetate esterase stain in five of seven cases. Cytogenetic analysis revealed structural abnormalities of chromosome 11 in four of the seven cases. Three of these studies showed a break at 11q23-24, the location of the human proto-oncogene ets-1. Clinically, two of these leukemias represented chronic myelogenous leukemia in blast crisis, and all cases behaved aggressively. The authors' data suggest that mixed lineage leukemias are an identifiable subset of adult acute leukemias and are associated with a poor prognosis.
Asunto(s)
Leucemia/genética , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Leucemia/inmunología , Leucemia/patología , Masculino , Persona de Mediana Edad , Fenotipo , Pronóstico , Proto-Oncogenes Mas , Coloración y EtiquetadoRESUMEN
Amplification of oncogenes has been found to be an important prognostic factor in behavior of patients' malignancies. In this study we have used new gel electrophoresis techniques to follow the location of amplified c-myc oncogene sequences in HL-60 promyelocytic leukemia cells. In passages 46-62 of the cells, the cells contain amplified c-myc sequences on submicroscopic circular extrachromosomal DNA (episomes). With increased passages in culture (passages 63-72) the cells lose the episome c-myc sequences with a shift of those sequences to double minutes. With additional passage in culture, the c-myc shifts from the double minutes to a chromosomal site der(5)t(5;17)(q11.2;q?11.2). Concomitant with the shift of the c-myc sequences into the chromosomal compartment is a phenotypic change of a shortened cell-doubling time. These studies provide the first molecular evidence of a progression from a submicroscopic location for amplified oncogene sequences to a chromosomal location for the amplified sequences. This molecularly documented model can now be used to test various strategies to prevent incorporation of extrachromosomally located oncogene sequences into chromosomal sites. Prevention of integration of the oncogene sequences into chromosomal sites could modulate progression of patients' tumors.
Asunto(s)
Aberraciones Cromosómicas , ADN de Neoplasias/genética , Amplificación de Genes , Leucemia Promielocítica Aguda/genética , Oncogenes , Plásmidos , Proteínas Proto-Oncogénicas/genética , División Celular , Humanos , Leucemia Promielocítica Aguda/patología , Hibridación de Ácido Nucleico , Proteínas Proto-Oncogénicas c-myc , Células Tumorales CultivadasRESUMEN
A patient with hypogonadotropic hypogonadism and anosmia (Kallmann's syndrome) had an associated chromosomal abnormality. Evaluation of the hypothalamic pituitary axis showed undetectable basal LH and FSH and slight increases in both gonadotropins in response to GnRH. Augmented gonadotropin response to GnRH after serial subcutaneous injections of GnRH confirmed a hypothalamic defect. Additional endocrine tests failed to reveal other hormone dysfunctions. A supernumerary chromosome was detected by routine chromosome analysis. The extra genetic material was identified by differential cytogenetic banding procedures as an accessory bisatellited marker chromosome originating from either chromosome group D or G. Chromosome analyses of both parents were normal. Our results suggest that, in at least some cases, the Kallmann's phenotype may be associated with a chromosome abnormality.
Asunto(s)
Aberraciones Cromosómicas/complicaciones , Gonadotropinas Hipofisarias/deficiencia , Hipogonadismo/complicaciones , Trastornos del Olfato/complicaciones , Adulto , Trastornos de los Cromosomas , Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/uso terapéutico , Humanos , Cariotipificación , Hormona Luteinizante/sangre , Masculino , SíndromeRESUMEN
We describe the clinical and cytogenetic findings of a 9 1/2 month old girl with a complex chromosome rearrangement resulting in a probable deletion of band 2p14. She does not resemble other reported cases of del(2p).
Asunto(s)
Deleción Cromosómica , Cromosomas Humanos 1-3 , Cromosomas Humanos 21-22 e Y , Cromosomas Humanos 6-12 y X , Femenino , Humanos , LactanteRESUMEN
Partial tetrasomy 9 is a very rare chromosome abnormality. Of the reported cases, most have had tetrasomy only of 9p arising from the formation of an isochromosome. In addition, mosaicism was found in five of the 12 previous cases. We report on a case of non-mosaic partial tetrasomy 9 involving all of the short arms and asymmetrical segments of the long arms.
Asunto(s)
Anomalías Múltiples/genética , Aberraciones Cromosómicas/genética , Cromosomas Humanos 6-12 y X , Trisomía , Enfermedades del Desarrollo Óseo/genética , Bandeo Cromosómico , Trastornos de los Cromosomas , Labio Leporino/genética , Fisura del Paladar/genética , Huesos Faciales/anomalías , Femenino , Humanos , Recién Nacido , Cariotipificación , Mosaicismo , Cráneo/anomalíasRESUMEN
Patients with a partial deletion of the long arm of chromosome 10 are rare. We report eight new cases involving various segments of 10q: one terminal deletion (10q26), four (8;10) translocations resulting in terminal deletions (10q26) and duplications (8q24.3), a de novo interstitial deletion (10q23), an interstitial deletion due to a (10;13) translocation (10q11.2----10q22.1), and a ring (10p15----10q26).
Asunto(s)
Deleción Cromosómica , Cromosomas Humanos 6-12 y X , Anomalías Múltiples/genética , Adulto , Preescolar , Dermatoglifia , Cara/anomalías , Femenino , Humanos , Lactante , Discapacidad Intelectual/genética , Masculino , Cromosomas en Anillo , Translocación GenéticaRESUMEN
Seven terminal deletions and four interstitial deletions of 6q have been reported. We present the clinical and cytogenetic findings of these cases and of two new patients with different interstitial deletions of 6q. Although there are too few cases of interstitial deletions to identify one or more clinical syndromes associated with monosomies of the more proximal regions of 6q, a terminal 6q deletion syndrome is proposed. Its major components are microcephaly with mental retardation, strabismus, apparently low-set malformed ears, a broad nasal bridge, micrognathia, apparently short neck, congenital heart defect, abnormal palmar creases, and various hand abnormalities.
Asunto(s)
Deleción Cromosómica , Cromosomas Humanos 6-12 y X , Anomalías Múltiples/genética , Adolescente , Preescolar , Dermatoglifia , Femenino , Humanos , Discapacidad Intelectual/genética , Masculino , SíndromeRESUMEN
Abnormalities of chromosome number, such as the autosomal trisomies and sex chromosome aneuploidies, are considered to be sporadic events with low and constant recurrence risk across populations. On the other hand, abnormalities of chromosome structure can be generated by environmental agents and also transmitted in families and therefore may accumulate in certain populations. Evidence from several geographically diverse newborn infant screening studies and from clinical cytogenetics laboratories (including our own) supports the hypothesis that the frequency of structural abnormalities varies among populations, whereas the frequency of numerical abnormalities remains relatively constant among populations. The data from our laboratory, based on 1,201 patients over a 6-year period, suggest a two- to nearly fourfold higher frequency of structural defects over that of other populations (8.8% vs 4.2% and 2.5% of samples tested). Some of the problems associated with making comparisons among the published data sets are discussed, along with alternative explanations for the variability in the frequency of structural defects reported in different populations.
Asunto(s)
Aberraciones Cromosómicas/epidemiología , Aneuploidia , Trastornos de los Cromosomas , Connecticut , Etnicidad , Europa (Continente) , Femenino , Humanos , Recién Nacido , Masculino , Manitoba , Moscú , Aberraciones Cromosómicas Sexuales/epidemiología , TexasRESUMEN
We describe a female infant with partial trisomy 8q who has microphthalmia, a cleft palate, micrognathia and a heart defect. Her dysmorphogenetic features closely resemble the characteristic pattern seen in the 17 cases thus far reported in the literature. Her chromosomal defect was caused by an unbalanced translocation, inherited through her father, and found to have been transmitted through at least 5 generations. Recently developed models designed to predict the most probable mode of unbalanced segregation from the meiotic quadrivalent and the likelihood that a chromosomally unbalanced fetus will survive to term are applied to this family's translocation. Also, the frequencies of potential reproductive outcomes from carriers of this translocation generated from empiric data are considered as a requisite aid to genetic counseling.