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1.
J Multidiscip Healthc ; 16: 1367-1377, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37215751

RESUMEN

Purpose: Tru-cut biopsy is a minimally invasive technique used to obtain tissue samples for the diagnosis of tumors, especially in patients where primary surgery is not indicated. The aim of this study was to assess the adequacy, accuracy and safety of the tru-cut biopsy for diagnosis in gynecological cancer. Methods: A retrospective population-based review of 328 biopsies was conducted. The indications for tru-cut biopsies were diagnosis of primary tumors, metastases of gynecological and non-gynecological tumors, and suspected recurrences. A tissue sample was considered adequate when the quality/quality was sufficient to identify the subtype/origin of the tumor. Potential factors affecting adequacy were analyzed using logistic regressions analyses. Accuracy was defined as agreement between the diagnosis of the tru-cut biopsy and the postoperative histology. The therapy plan was registered, and the clinical applicability of the tru-cut biopsy was investigated. Complications within 30 days after the biopsy procedure were registered. Results: In total, 300 biopsies were identified as tru-cut biopsies. The overall adequacy was 86.3%, varying between 80.8% and 93.5%, respectively, when performed by a gynecological oncologist or a gynecologist with a subspecialty in ultrasound diagnosis. Sampling of a pelvic mass had a lower adequacy (81.6%) compared with sampling of the omentum (93.9%) or carcinomatosis (91.5%). The accuracy was 97.5%, and the complication rate was 1.3%. Conclusion: The tru-cut biopsy is a safe and reliable diagnostic method with a high accuracy and a good adequacy, depending on the site of the tissue sample, indications for the biopsy and the experience of the operator.

2.
Ultrasound Med Biol ; 39(9): 1682-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23849391

RESUMEN

The aim of this study was to investigate myocardial wall motion using echocardiography and color-coded tissue velocity imaging and to generate a cardiac state diagram for evaluation of the duration of the pre- and post-ejection phases in asphyxiated fetal lambs. Six near-term lambs were partly exteriorized and brought to cardiac arrest through asphyxia. Echocardiography measurements were recorded simultaneously with arterial blood sampling for lactate and blood gases. All fetal lambs exhibited prolongation of the pre- and post-ejection phases at the time when the most pronounced changes in lactate concentration and pH occurred. The mean change in duration of the pre- and post-ejection phases for all fetal lambs was 36 ± 7 ms (p < 0.002) and 77 ± 17 ms (p < 0.019), respectively, and the percentage change was 50% (p < 0.001) and 38% (p < 0.049), respectively. As asphyxia progressed in fetal lambs, the duration of the pre- and post-ejection phases increased. The cardiac state diagram has the potential to be a comprehensible tool for detecting fetal asphyxia.


Asunto(s)
Asfixia Neonatal/diagnóstico por imagen , Asfixia Neonatal/fisiopatología , Hipoxia Fetal/diagnóstico por imagen , Hipoxia Fetal/fisiopatología , Interpretación de Imagen Asistida por Computador/métodos , Volumen Sistólico , Ultrasonografía Prenatal/métodos , Algoritmos , Animales , Simulación por Computador , Aumento de la Imagen/métodos , Modelos Cardiovasculares , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ovinos
3.
PLoS One ; 8(5): e64033, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23700452

RESUMEN

OBJECTIVE: An experienced sonographer can by listening to the Doppler audio signals perceive various timbres that distinguish different types of umbilical artery flow despite an unchanged pulsatility index (PI). Our aim was to develop an objective measure of the Doppler audio signals recorded from fetoplacental circulation in a sheep model. METHODS: Various degrees of pathological flow velocity waveforms in the umbilical artery, similar to those in human complicated pregnancies, were induced by microsphere embolization of the placental bed (embolization model, 7 lamb fetuses, 370 Doppler recordings) or by fetal hemodilution (anemia model, 4 lamb fetuses, 184 recordings). A subjective 11-step operator auditory scale (OAS) was related to conventional Doppler parameters, PI and time average mean velocity (TAM), and to sound frequency analysis of Doppler signals (sound frequency with the maximum energy content [MAXpeak] and frequency band at maximum level minus 15 dB [MAXpeak-15 dB] over several heart cycles). RESULTS: WE FOUND A NEGATIVE CORRELATION BETWEEN THE OAS AND PI: median Rho -0.73 (range -0.35- -0.94) and -0.68 (range -0.57- -0.78) in the two lamb models, respectively. There was a positive correlation between OAS and TAM in both models: median Rho 0.80 (range 0.58-0.95) and 0.90 (range 0.78-0.95), respectively. A strong correlation was found between TAM and the results of sound spectrum analysis; in the embolization model the median r was 0.91 (range 0.88-0.97) for MAXpeak and 0.91 (range 0.82-0.98) for MAXpeak-15 dB. In the anemia model, the corresponding values were 0.92 (range 0.78-0.96) and 0.96 (range 0.89-0.98), respectively. CONCLUSION: Audio-spectrum analysis reflects the subjective perception of Doppler sound signals in the umbilical artery and has a strong correlation to TAM-velocity. This information might be of importance for clinical management of complicated pregnancies as an addition to conventional Doppler parameters.


Asunto(s)
Ultrasonografía Prenatal/métodos , Arterias Umbilicales/diagnóstico por imagen , Animales , Percepción Auditiva , Velocidad del Flujo Sanguíneo , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Hipoxia Fetal/diagnóstico por imagen , Feto/irrigación sanguínea , Humanos , Personal de Laboratorio Clínico , Circulación Placentaria , Embarazo , Ovinos , Espectrografía del Sonido , Ultrasonografía Doppler en Color , Arterias Umbilicales/anomalías
4.
Blood ; 113(19): 4790-8, 2009 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-19074736

RESUMEN

Although successful in utero hematopoietic cell transplantation (IUHCT) of X-linked severe combined immune deficiency (X-SCID) with enriched stem and progenitor cells was achieved more than a decade ago, it remains applied only in rare cases. Although this in part reflects that postnatal transplantations have overall given good results, there are no direct comparisons between IUHCT and postnatal transplantations of X-SCID. The proposed tolerance of the fetal immune system to foreign human leukocyte antigen early in gestation, a main rationale behind IUHCT, has recently been challenged by evidence for a considerable immune barrier against in utero transplanted allogeneic bone marrow cells. Consequently, there is need for further exploring the application of purified stem and progenitor cells to overcome this barrier also in IUHCT. Herein, we demonstrate in a congenic setting that recently identified lymphoid-primed multipotent progenitors are superior to hematopoietic stem cells in providing rapid lymphoid reconstitution after IUHCT of X-SCID recipients, and sustain in the long-term B cells, polyclonal T cells, as well as short-lived B-cell progenitors and thymic T-cell precursors. We further provide evidence for IUHCT of hematopoietic stem cells giving superior B- and T-cell reconstitution in fetal X-SCID recipients compared with neonatal and adolescent recipients.


Asunto(s)
Células Progenitoras Linfoides/trasplante , Células Madre Multipotentes/trasplante , Células Madre/fisiología , Linfocitos T/metabolismo , Útero/trasplante , Enfermedades por Inmunodeficiencia Combinada Ligada al Cromosoma X/terapia , Animales , Animales Recién Nacidos , Médula Ósea/metabolismo , Femenino , Feto/fisiología , Reordenamiento Génico , Células Madre Hematopoyéticas/fisiología , Células Progenitoras Linfoides/inmunología , Células Progenitoras Linfoides/metabolismo , Linfopoyesis , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Células Madre Multipotentes/inmunología , Células Madre Multipotentes/metabolismo , Células Mieloides/metabolismo , Linfocitos T/citología , Linfocitos T/inmunología , Timo/citología , Timo/inmunología , Útero/inmunología , Enfermedades por Inmunodeficiencia Combinada Ligada al Cromosoma X/inmunología
5.
Nat Cell Biol ; 10(5): 584-92, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18425115

RESUMEN

Recent studies have suggested that regeneration of non-haematopoietic cell lineages can occur through heterotypic cell fusion with haematopoietic cells of the myeloid lineage. Here we show that lymphocytes also form heterotypic-fusion hybrids with cardiomyocytes, skeletal muscle, hepatocytes and Purkinje neurons. However, through lineage fate-mapping we demonstrate that such in vivo fusion of lymphoid and myeloid blood cells does not occur to an appreciable extent in steady-state adult tissues or during normal development. Rather, fusion of blood cells with different non-haematopoietic cell types is induced by organ-specific injuries or whole-body irradiation, which has been used in previous studies to condition recipients of bone marrow transplants. Our findings demonstrate that blood cells of the lymphoid and myeloid lineages contribute to various non-haematopoietic tissues by forming rare fusion hybrids, but almost exclusively in response to injuries or inflammation.


Asunto(s)
Fusión Celular , Linaje de la Célula , Células Madre Hematopoyéticas/fisiología , Linfocitos/fisiología , Células Mieloides/fisiología , Radiación , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/fisiología , Trasplante de Médula Ósea , Femenino , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células Madre Hematopoyéticas/citología , Hepatocitos/citología , Hepatocitos/fisiología , Linfocitos/citología , Ratones , Ratones SCID , Ratones Transgénicos , Músculo Esquelético/citología , Células Mieloides/citología , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología , Células de Purkinje/citología , Células de Purkinje/fisiología , Quimera por Trasplante
6.
J Immunol ; 180(4): 2045-53, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18250409

RESUMEN

Hematopoietic stem cell (HSC) numbers are tightly regulated and maintained in postnatal hematopoiesis. Extensive studies have supported a role of the cytokine tyrosine kinase receptor Kit in sustaining cycling HSCs when competing with wild-type HSCs posttransplantation, but not in maintenance of quiescent HSCs in steady state adult bone marrow. In this study, we investigated HSC regulation in White Spotting 41 (Kit(W41/W41)) mice, with a partial loss of function of Kit. Although the extensive fetal HSC expansion was Kit-independent, adult Kit(W41/W41) mice had an almost 2-fold reduction in long-term HSCs, reflecting a loss of roughly 10,000 Lin(-)Sca-1(+)Kit(high) (LSK)CD34(-)Flt3(-) long-term HSCs by 12 wk of age, whereas LSKCD34(+)Flt3(-) short-term HSCs and LSKCD34(+)Flt3(+) multipotent progenitors were less affected. Whereas homing and initial reconstitution of Kit(W41/W41) bone marrow cells in myeloablated recipients were close to normal, self-renewing Kit(W41/W41) HSCs were progressively depleted in not only competitive but also noncompetitive transplantation assays. Overexpression of the anti-apoptotic regulator BCL-2 partially rescued the posttransplantation Kit(W41/W41) HSC deficiency, suggesting that Kit might at least in the posttransplantation setting in part sustain HSC numbers by promoting HSC survival. Most notably, accelerated in vivo BrdU incorporation and cell cycle kinetics implicated a previously unrecognized role of Kit in maintaining quiescent HSCs in steady state adult hematopoiesis.


Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Proteínas Proto-Oncogénicas c-kit/fisiología , Fase de Descanso del Ciclo Celular , Envejecimiento/genética , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Bromodesoxiuridina/metabolismo , Ciclo Celular/genética , Feto , Hematopoyesis/genética , Cinética , Hígado/citología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Células Madre Multipotentes/citología , Células Madre Multipotentes/metabolismo , Pigmentación/genética , Mutación Puntual , Proteínas Proto-Oncogénicas c-kit/genética , Fase de Descanso del Ciclo Celular/genética
8.
Immunity ; 26(4): 407-19, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17433729

RESUMEN

Recent studies implicated the existence of adult lymphoid-primed multipotent progenitors (LMPPs) with little or no megakaryocyte-erythroid potential, questioning common myeloid and lymphoid progenitors as obligate intermediates in hematopoietic stem cell (HSC) lineage commitment. However, the existence of LMPPs remains contentious. Herein, global and single-cell analyses revealed a hierarchical organization of transcriptional lineage programs, with downregulation of megakaryocyte-erythroid genes from HSCs to LMPPs, sustained granulocyte-monocyte priming, and upregulation of common lymphoid (but not B and T cell-specific) genes. These biological and molecular relationships, implicating almost mutual exclusion of megakaryocyte-erythroid and lymphoid pathways, are established already in fetal hematopoiesis, as evidenced by existence of LMPPs in fetal liver. The identification of LMPPs and hierarchically ordered transcriptional activation and downregulation of distinct lineage programs is compatible with a model for HSC lineage commitment in which the probability for undergoing different lineage commitment fates changes gradually when progressing from HSCs to LMPPs.


Asunto(s)
Células Madre Adultas/inmunología , Linaje de la Célula/genética , Feto/inmunología , Regulación del Desarrollo de la Expresión Génica , Linfocitos/inmunología , Células Madre Multipotentes/inmunología , Células Madre Adultas/citología , Animales , Desarrollo Fetal/genética , Feto/citología , Perfilación de la Expresión Génica , Linfocitos/citología , Ratones , Células Madre Multipotentes/citología , Transcripción Genética
9.
J Matern Fetal Neonatal Med ; 17(2): 101-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16076616

RESUMEN

OBJECTIVE: To investigate the perinatal adaptive response of the adrenal blood flow/adrenal fractional moving blood volume (AFMBV) and carotid blood flow (CBF), in sheep fetuses subjected to severe acute intrauterine hypoxia/asphyxia induced by total cord occlusion. METHODS: Adrenal blood flow velocity, AFMBV and CBF were measured in 13 exteriorized fetal sheep; eight of them underwent total umbilical cord occlusion to induce severe acute hypoxia/asphyxia. Five lambs were used as sham controls. Middle adrenal artery pulsatility index (MAAPI) and mean velocity (MAAMV) were recorded with pulsed Doppler ultrasound. AFMBV was estimated using power Doppler ultrasound. CBF was recorded with a transonic flowmeter. In the neonatal period, after resuscitation all lambs were followed for a 4-hour period and AFMBV and CBF were recorded. Mean arterial blood pressure (MABP) and fetal heart rate were recorded continuously. Arterial cortisol levels were measured at the beginning and at the end of the fetal and neonatal periods. RESULTS: Following the total cord occlusion, there was a significant reduction in the CBF, MABP, and heart rate and adrenal flow/AFMBV after 2, 4 and 5 min, respectively. Cortisol levels in the asphyctic lambs at the end of the cord occlusion were significantly lower than those in controls. After resuscitation, the asphyctic lambs showed increased AFMBV and cortisol levels, and reduced MABP as compared to control lambs. No differences were found in CBF, MAAPI and MAAMV. Thereafter, no differences were observed between the two groups in any of the studied parameters. At the end of the cord occlusion period, there was a significant correlation between AFMBV and MABP (r=0.69), between AFMBV and CBF (r =0.65) and between CBF and MABP (r=0.89). CONCLUSION: During severe acute intrauterine hypoxia, the fetal lamb is able to maintain the blood flow to the brain and the adrenal gland for 3-5 min. Changes in the AFMBV and the CBF were highly correlated to the changes in MABP. Adrenal FMBV and cortisol levels were higher in lamb neonates exposed to severe intrauterine asphyxia.


Asunto(s)
Glándulas Suprarrenales/irrigación sanguínea , Arterias Carótidas/fisiología , Hipoxia Fetal/fisiopatología , Isquemia/complicaciones , Cordón Umbilical/irrigación sanguínea , Animales , Velocidad del Flujo Sanguíneo , Circulación Cerebrovascular/fisiología , Hipoxia Fetal/etiología , Feto , Ovinos
10.
Cell ; 121(2): 295-306, 2005 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-15851035

RESUMEN

All blood cell lineages derive from a common hematopoietic stem cell (HSC). The current model implicates that the first lineage commitment step of adult pluripotent HSCs results in a strict separation into common lymphoid and common myeloid precursors. We present evidence for a population of cells which, although sustaining a high proliferative and combined lympho-myeloid differentiation potential, have lost the ability to adopt erythroid and megakaryocyte lineage fates. Cells in the Lin-Sca-1+c-kit+ HSC compartment coexpressing high levels of the tyrosine kinase receptor Flt3 sustain granulocyte, monocyte, and B and T cell potentials but in contrast to Lin-Sca-1+c-kit+Flt3- HSCs fail to produce significant erythroid and megakaryocytic progeny. This distinct lineage restriction site is accompanied by downregulation of genes for regulators of erythroid and megakaryocyte development. In agreement with representing a lymphoid primed progenitor, Lin-Sca-1+c-kit+CD34+Flt3+ cells display upregulated IL-7 receptor gene expression. Based on these observations, we propose a revised road map for adult blood lineage development.


Asunto(s)
Linaje de la Célula/fisiología , Células Progenitoras Mieloides/clasificación , Células Progenitoras Mieloides/citología , Factores de Edad , Animales , Diferenciación Celular , Regulación hacia Abajo , Eritrocitos/citología , Regulación de la Expresión Génica , Técnicas In Vitro , Megacariocitos/citología , Ratones , Ratones Endogámicos C57BL , Células Progenitoras Mieloides/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Tirosina Quinasa 3 Similar a fms
11.
Blood ; 102(3): 881-6, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12676789

RESUMEN

The cytokine tyrosine kinase receptors c-kit and flt3 are expressed and function in early mouse and human hematopoiesis. Through its ability to promote ex vivo expansion and oncoretroviral transduction of primitive human hematopoietic progenitors, the flt3 ligand (FL) has emerged as a key stimulator of candidate human hematopoietic stem cells (HSCs). However, recent studies in the mouse suggest that though it is present on short-term repopulating cells, flt3 is not expressed on bone marrow long-term reconstituting HSCs, the ultimate target for the development of cell replacement and gene therapy. Herein we demonstrate that though only a fraction of human adult bone marrow and cord blood CD34+long-term culture-initiating cells (LTC-ICs) express flt3, most cord blood lymphomyeloid HSCs capable of in vivo reconstituting nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice are flt3+. The striking difference in flt3 and c-kit expression on mouse and candidate human HSCs translated into a corresponding difference in flt3 and c-kit function because FL was more efficient than SCF at supporting the survival of candidate human HSCs. In contrast, SCF is far superior to FL as a viability factor for mouse HSCs. Thus, the present data provide compelling evidence for a contrasting expression and response pattern of flt3 and c-kit on mouse and human HSCs.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/metabolismo , Proteínas de la Membrana/fisiología , Proteínas Proto-Oncogénicas c-kit/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Tirosina Quinasas Receptoras/fisiología , Animales , Antígenos CD34 , Médula Ósea/metabolismo , Supervivencia Celular , Sangre Fetal/citología , Supervivencia de Injerto , Células Madre Hematopoyéticas/citología , Humanos , Linfopoyesis , Ratones , Ratones SCID , Mielopoyesis , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas c-kit/biosíntesis , Proteínas Tirosina Quinasas Receptoras/biosíntesis , Factor de Células Madre , Trasplante Heterólogo , Tirosina Quinasa 3 Similar a fms
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