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1.
J Endocrinol Invest ; 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882947

RESUMEN

PURPOSE: The finding of mTOR overactivation in patients affected by pancreatic neuroendocrine tumors (Pa-NETs) led to their treatment with the mTOR inhibitor everolimus. Unfortunately, the efficacy of everolimus is restricted by the occurrence of resistance. The mechanisms leading to Pa-NETs' progression and resistance are not well understood. Notably, chronic inflammation is implicated in NET development. NF-kB is involved in inflammation and drug resistance mechanisms through the activation of several mediators, including STAT3. In this respect, NF-κB and STAT3 interaction is implicated in the crosstalk between inflammatory and tumor cells. METHODS: We investigated the expression of NF-kB in different Pa-NETs by RT-qPCR and immunohistochemistry. Then, we studied the role of NF-κB and STAT3 interplay in QGP-1 cells. Subsequently, we assessed the impact of NF-κB and STAT3 inhibitors in QGP-1 cell proliferation and spheroids growth. Finally, we evaluated the implication of the NF-kB pathway in everolimus-resistant Pa-NET cells. RESULTS: We found that the increased NF-kB expression correlates  with a higher grade in Pa-NETs. The activation of the STAT3 pathway induced by TNFα is mediated by NF-kB p65. NF-kB p65 and STAT3 inhibitors decrease QGP-1 viability, spheroids growth, and Pa-NETs cell proliferation. These effects are maintained in everolimus-resistant QGP-1R cells. Interestingly, we found that NF-kB, STAT3, IL-8, and SOCS3 are overexpressed in QGP-1R compared to QGP-1. CONCLUSION: Since the NF-kB pathway is implicated in Pa-NETs' progression and resistance to everolimus, these data could explain the potential use of NF-kB as a novel therapeutic target in Pa-NET patients.

2.
J Dairy Sci ; 102(7): 5957-5961, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31128873

RESUMEN

Some Lactobacillus strains may contribute to the health of the host when administered in adequate concentrations, demonstrating their probiotic potential. In contrast, Listeria monocytogenes is a foodborne pathogen that can cause enteropathy, meningoencephalitis, abortion, and septicemia. The aim of this survey was to evaluate the in vitro and in vivo probiotic potential of Lactobacillus plantarum B7 and Lactobacillus rhamnosus D1, isolated from Minas artisanal cheese of the Serra da Canastra (Minas Gerais, Brazil), against Lis. monocytogenes. We submitted B7 and D1 to in vitro testing (antibiogram, tolerance to bile salts and artificial gastric fluid, and spot-on-lawn) and in vivo testing (relative weight gain in mice). Both Lactobacillus strains demonstrated in vitro inhibitory activity against Lis. monocytogenes, as well as sensitivity to antimicrobials and resistance to gastric acids and bile salts. In the in vivo assays, mice treated with D1 gained more weight than mice in the other groups. These results indicate that D1 could have higher probiotic potential than B7 because improvements in feed conversion may help animals fight infection.


Asunto(s)
Queso/microbiología , Lacticaseibacillus rhamnosus/química , Lactobacillus plantarum/química , Listeria monocytogenes/efectos de los fármacos , Probióticos/farmacología , Animales , Ácidos y Sales Biliares/química , Brasil , Masculino , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana
3.
J Biol Regul Homeost Agents ; 32(2 Suppl. 1): 217-221, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29460545

RESUMEN

This study has tested the effects of hyperbaric oxygen in periodontal structures in agreement with the theories supported by literature research. Eight patients, from 30 to 50 years-of-age, were tested with pure oxygen inhalation, at the 2.5 ATA absolute pressure. Main approved tests of periodontal health were evaluated before and after HBOT’s cycles. The results in all patients treated with HBOT, have founded clear improvement of clinical and instrumental parameters.


Asunto(s)
Encía/efectos de los fármacos , Encía/fisiología , Oxigenoterapia Hiperbárica , Oxígeno/uso terapéutico , Adulto , Salud , Humanos , Persona de Mediana Edad , Oxígeno/administración & dosificación
4.
J Biol Regul Homeost Agents ; 32(6 Suppl. 1): 35-40, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30644279

RESUMEN

The knee is the largest and most complex joint in the human body. Traumatic events, such as anterior cruciate ligament (ACL) tear, can lead to an alteration of joint tissues homeostasis. Literature reports an evident correlation between abnormal joint biomechanics and the status of articular tissues. These alterations, due to a sub-optimal ACL reconstruction, may result in an increasing risk of developing degenerative pathologies, such as osteoarthritis. Thus, the identification of the optimal surgical technique is a highly demanding issue in ACL reconstruction. The aim of this study was to analyze the correlation between joint cartilage conditions and knee biomechanics in ACL reconstructions, by integrating MRI T2 mapping investigations, radiostereophotogrammetry-based gait analysis and subject-specific musculoskeletal modelling.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Reconstrucción del Ligamento Cruzado Anterior , Cartílago Articular/diagnóstico por imagen , Fenómenos Biomecánicos , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética
5.
Br J Dermatol ; 172(1): 64-73, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24910265

RESUMEN

BACKGROUND: Recent reports have revealed the therapeutic potential of cell-mediated immunity in neoplasms such as cutaneous squamous cell carcinoma (SCC). OBJECTIVES: To define the antigenic coexpression of regulatory T cells (Tregs) and plasmacytoid dendritic cells (pDCs) and assess the CD8(+) /Foxp3(+) CD25(+) cell ratio at peritumoral and intratumoral levels in order to investigate a correlation with the aggressiveness of SCC tumours. METHODS: We evaluated the content and distribution of Foxp3(+) CD25(+) Treg and CD123(+) pDC infiltration and assessed CD8(+) /Foxp3(+) CD25(+) cell ratio at peritumoral and intratumoral levels in 40 SCCs (20 well-differentiated, G1; and 20 moderately to poorly differentiated, G2-G3) to investigate a correlation with their aggressiveness. We determined the profiles of Tregs and CD123(+) cells; immunostained for CD4, CD8, CD123, interleukin (IL)-1 and transforming growth factor (TGF)-ß1; and unequivocally double stained for Foxp3CD25. RESULTS: Peritumorally, CD4, CD8 and Foxp3 expression showed no difference between the two groups. CD123(+) cells were fewer in G2-G3 (P = 0·0005), while Foxp3(+) CD25(+) cells were more numerous (P = 0·0005). The Foxp3(+) CD25(+) /Foxp3(+) ratio was higher in G2-G3 cases (P = 0·0005), confirming the trend in this group of activated T lymphocytes towards total Treg Foxp3(+) cells, while the CD8(+) /Foxp3(+) CD25(+) ratio was higher in G1 (P = 0·0005). Intratumorally, CD4(+) and CD8(+) cells infiltrated G2-G3 (P = 0·048) more than G1 (P = 0·004), whereas almost all cells were CD123 negative. Regarding Foxp3CD25, TGF-ß1 and IL-10, they were less expressed in G1, whereas they were positive in G2-G3 (P < 0·05). The CD8(+) /Foxp3(+) CD25(+) ratio was similar to that observed in peritumoral infiltration. CONCLUSIONS: Our data suggest that intratumoral recruitment of Tregs, high expression of TGF-ß1 and IL-10, almost negative CD123+, and a low CD8(+) /Foxp3(+) CD25(+) T-cell ratio may contribute to the aggressiveness of cutaneous SCC, as already evidenced for other solid tumours.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Carcinoma de Células Escamosas/inmunología , Factores de Transcripción Forkhead/metabolismo , Inmunidad Celular/fisiología , Neoplasias Cutáneas/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Células Dendríticas/inmunología , Femenino , Humanos , Interleucina-10/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Neoplasias Cutáneas/patología , Factor de Crecimiento Transformador beta/metabolismo
6.
ESMO Open ; 9(4): 102991, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38631269

RESUMEN

BACKGROUND: Advances in surgical techniques and systemic treatments have increased the likelihood of achieving radical surgery and long-term survival in metastatic colorectal cancer (mCRC) patients with initially unresectable colorectal liver metastases (CRLMs). Nonetheless, roughly half of the patients resected after an upfront systemic therapy experience disease relapse within 6 months from surgery, thus leading to the question whether surgery is actually beneficial for these patients. MATERIALS AND METHODS: A real-world dataset of mCRC patients with initially unresectable liver-limited disease treated with conversion chemotherapy followed by radical resection of CRLMs at three high-volume Italian institutions was retrospectively assessed with the aim of investigating the association of baseline and pre-surgical clinical, radiological and molecular factors with the risk of relapse within 6 or 12 months from surgery. RESULTS: Overall, 268 patients were included in the analysis and 207 (77%) experienced recurrence. Ninety-six (46%) of them had disease relapse within 6 months after CRLM resection and in spite of several variables associated with early recurrence at univariate analyses, only primary tumour resection at diagnosis [odds ratio (OR) 0.53, 95% confidence interval (CI) 0.32-0.89, P = 0.02] remained significant in the multivariable model. Among patients with resected primary tumours, pN+ stage was associated with higher risk of disease relapse within 6 months (OR 3.02, 95% CI 1.23-7.41, P = 0.02). One hundred and forty-nine patients (72%) had disease relapse within 12 months after CRLMs resection but none of the analysed variables was independently associated with outcome. CONCLUSIONS: Clinical, radiological and molecular factors assessed before and after conversion chemotherapy do not reliably predict early recurrence after secondary resection of initially unresectable CRLMs. While novel markers are needed to optimize the cost/efficacy balance of surgical procedures, CRLM resection should be offered as soon as metastases become resectable during first-line chemotherapy to all patients eligible for surgery.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Recurrencia Local de Neoplasia , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Hepatectomía/métodos
7.
Heredity (Edinb) ; 111(1): 57-65, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23549337

RESUMEN

The Foxl2 (forkhead box L2) gene is an important member of the forkhead domain family, primarily responsible for the development of ovaries during female sex differentiation. The evolutionary studies conducted previously considered the presence of paralog Foxl2 copies only in teleosts. However, to search for possible paralog copies in other groups of vertebrates and ensure that all predicted copies were homolog to the Foxl2 gene, a broad evolutionary analysis was performed, based on the forkhead domain family. A total of 2464 sequences for the forkhead domain were recovered, and subsequently, 64 representative sequences for Foxl2 were used in the evolutionary analysis of this gene. The most important contribution of this study was the discovery of a new subgroup of Foxl2 copies (ortholog to Foxl2B) present in the chondrichthyan Callorhinchus milii, in the coelacanth Latimeria chalumnae, in the avian Taeniopygia guttata and in the marsupial Monodelphis domestica. This new scenario indicates a gene duplication event in an ancestor of gnathostomes. Furthermore, based on the analysis of the syntenic regions of both Foxl2 copies, the duplication event was not exclusive to Foxl2. Moreover, the duplicated copy distribution was shown to be complex across vertebrates, especially in tetrapods, and the results strongly support a loss of this copy in eutherian species. Finally, the scenario observed in this study suggests an update for Foxl2 gene nomenclature, extending the actual suggested teleost naming of Foxl2A and Foxl2B to all vertebrate sequences and contributing to the establishment of a new evolutionary context for the Foxl2 gene.


Asunto(s)
Factores de Transcripción Forkhead/genética , Duplicación de Gen , Genoma , Vertebrados/genética , Animales , Evolución Molecular , Femenino , Dosificación de Gen , Masculino , Datos de Secuencia Molecular , Filogenia , Sintenía , Vertebrados/clasificación
8.
Chromosome Res ; 20(2): 279-92, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22234547

RESUMEN

To better understand genomic and chromosomal organization and evolutionary patterns of the U1 snRNA gene in cichlid fish, the gene was cytogenetically mapped and comparatively analyzed in 19 species belonging to several clades of the group. Moreover, the distribution and organization of U1 snRNA gene was analyzed in the Oreochromis niloticus genome. The results indicated high conservation of one chromosomal cluster of U1 snRNA in the African, Asian, and South American species, with few variations in the chromosomal position of the clusters in the South American species. The genomic analysis of U1 revealed a distinct scenario from that observed under the cytogenetic mapping. An enrichment of the U1 gene on linkage group (LG) 14 was observed that did not correspond to the same chromosome that harbors the U1 cluster identified by cytogenetic mapping. Moreover, it was revealed that the presence of several distinct transposable elements in the U1 gene flanking regions could be involved in the spreading of this sequence, but the generation of new, large snRNA clusters (detectable by fluorescent in situ hybridization, FISH) is apparently hampered. These results contribute to the understanding of multigene families' evolution and reinforce the utility of integrative analysis and the use of cytogenetic and bioinformatic methods to address the genomic and chromosomal evolutionary patterns of repeated DNAs among vertebrates. Moreover, the U1 gene represents a useful new chromosomal marker for cytogenetic studies.


Asunto(s)
Mapeo Cromosómico , Cíclidos/genética , Genoma , ARN Nuclear Pequeño/genética , Animales , Secuencia de Bases , ADN Intergénico , Orden Génico , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Alineación de Secuencia
9.
Minerva Stomatol ; 62(1-2): 43-9, 2013.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-23422682

RESUMEN

We report a case of a 37-year-old caucasian woman presenting a 1 cm pinkish nodular asymptomatic lesion of the hard palate, slowly growing in the last years. The lesion underwent to biopsy. Histological analysis showed the nevus tissue layered under a continuous squamous epithelium. The stroma contained nests of medium-sized round cells, with regular monomorphous nuclei. The nevus cells were immunohistochemically positive for S-100 protein, while melanin, visualized by Masson-Fontana silver staining, was absent. Therefore a diagnosis of non pigmented melanocytic nevus was formulated. Because of its rarity and to avoid any risk of malignant transformation, a surgical treatment with wide excision was chosen; the surgical wound was previously covered with a membrane of fibrin and autologous platelets, and subsequently sutured, resulting in a total heal. This procedure seems to be the most reliable to approach melanocytic lesions of the oral cavity. Clinical diagnosis of non-pigmented nevi, either flat or protruding, is difficult, because the nevus shows a pinkish colour that is indistinguishable from that of the surrounding mucosa. Moreover, attention is required when similar clinical evidence occurs, because the localization inside the oral cavity may offer several problems of differential diagnosis.


Asunto(s)
Nevo Pigmentado/cirugía , Procedimientos Quirúrgicos Orales/métodos , Neoplasias Palatinas/cirugía , Adulto , Biomarcadores de Tumor/análisis , Plaquetas , Femenino , Fibrina/uso terapéutico , Humanos , Melanocitos/química , Melanocitos/ultraestructura , Nevo Pigmentado/química , Nevo Pigmentado/patología , Neoplasias Palatinas/química , Neoplasias Palatinas/patología , Proteínas S100/análisis , Cicatrización de Heridas
10.
Cytogenet Genome Res ; 133(1): 34-42, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21196713

RESUMEN

To enhance our understanding of the organization of the genome and chromosome evolution of cichlid fish species, we have isolated and physically mapped onto the chromosomes the transposable elements (TEs) Rex1, Rex3 and Rex6, which are conserved in teleost fish, in the chromosomes of African and South American cichlid species. The physical mapping of different Rex elements showed that they are primarily compartmentalized in the pericentromeric heterochromatic regions, although dispersed or clustered signals in euchromatic regions were also observed. The presence of TEs in heterochromatin can be correlated with their role in the structure and organization of heterochromatic areas (such as centromeres) or with the lower selective pressure that act on these gene-poor regions. The Rex elements were also concentrated in the largest chromosome pair of the Nile tilapia, Oreochromis niloticus. This chromosome pair is supposed to have originated by fusions, demonstrating the possible involvement of TEs with chromosome rearrangements. Besides general patterns of chromosomal distribution, comparative analysis suggests that Rex elements could differ in their chromosomal distribution among different fish groups or species and that intrinsic aspects of the genomes could influence the spread, accumulation or elimination of TEs.


Asunto(s)
Cromosomas , Cíclidos/genética , Elementos Transponibles de ADN , Retroelementos , Animales , Análisis Citogenético
11.
Clin Endocrinol (Oxf) ; 75(4): 528-34, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21575027

RESUMEN

OBJECTIVE: The percentage of patients with thyroid cancer incidentally diagnosed during a (18) F-fluorodeoxyglucose Positron Emission Tomography with computed tomography (CT) (FDG-PET/CT) for nonthyroid diseases ranges between 26% and 50%. DESIGN: Retrospective assessment of the clinical and pathological features of thyroid incidentalomas at FDG-PET/CT, aiming to identify potential predictors of malignancy. PATIENTS: Fifty-two patients with incidental thyroid uptake at FDG-PET/CT were retrospectively included [38 W, age 64·1 ± 12·5 years (mean ± SD)]. An arbitrary cut-off level of 5·0 for the 'maximum standardized uptake value' (SUV max) was chosen to differentiate benign from malignant tumours. Complete thyroid function, neck ultrasonography (US) features, and cyto-histological results were reported for all cases. RESULTS: In our institution, the prevalence of incidental thyroid (18) F-fluorodeoxyglucose ((18) F-FDG) uptake was nearly 1·76%. The prevalence of focal uptake correlated with greater risk of malignancy (P < 0·01). In particular, the euthyroidism (P < 0·003) and a SUV max >5·0 (P < 0·0001) were associated with the diagnosis of thyroid cancer. Diffusely increased FDG-PET/CT uptake in the thyroid was related to benign conditions. CONCLUSIONS: The presence of focal uptake with high SUV max and euthyroidism correlate with high likelihood of malignancy. Performing a neck US would have to be recommended in all patients with euthyroidism and an incidental FDG-PET/CT focal thyroid uptake. We do not suggest to use FDG-PET/CT as a screening tool for thyroid cancer in the general population, because of both its high cost and low incidence of thyroid incidentaloma at FDG-PET/CT.


Asunto(s)
Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
12.
Clin Exp Dermatol ; 36(6): 617-20, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21771005

RESUMEN

We describe two nonconsanguineous white patients with multiple pigmented basal cell carcinomas (BCCs) that were histopathologically confirmed. The first patient had calcification of the cerebral falx, multiple keratocysts in the jaw, and other malformations of the cranial and finger bones. The second patient presented with multiple dermoid cysts, calcification of the cerebral falx, keratocysts of the mandible, and agenesis of left kidney. Both patients had palmar pits. Both denied any family history of cutaneous tumours. On dermatoscopic examination of patient 1, multiple, bluish, confluent and large globules were seen. The second patient had blue ovoid globules, arborizing vessels, and areas shaped like maple leaves and spoke-wheels. Based on the clinical and radiological features we diagnosed both patients as having Gorlin syndrome (GS). To our knowledge, there are no previous reports of white patients with GS showing only pigmented BCCs. The dermatoscopic patterns were different in the two patients, and to our knowledge, this is the first report of a patient with GS showing a spoked-wheel dermatoscopic pattern.


Asunto(s)
Síndrome del Nevo Basocelular/patología , Neoplasias Óseas/patología , Carcinoma Basocelular/patología , Neoplasias Cutáneas/patología , Adulto , Dermoscopía , Síndrome de Hamartoma Múltiple , Humanos , Masculino , Persona de Mediana Edad , Nevo Pigmentado/patología
13.
J Fish Biol ; 78(4): 1239-48, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21463318

RESUMEN

Cytogenetic markers were used to compare the karyotypes of an isolated population of Hoplias malabaricus with others previously described. The results revealed peculiar characteristics that indicate a new independent evolutionary unit within the H. malabaricus complex.


Asunto(s)
Cromosomas/genética , Análisis Citogenético , Peces/genética , Variación Genética , Animales , Femenino , Cariotipificación , Masculino , Polimorfismo Genético
14.
Nature ; 403(6765): 54-6, 2000 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-10638747

RESUMEN

Adaptive-optics systems can in principle allow a telescope to achieve performance at its theoretical maximum (limited only by diffraction), by correcting in real time for the distortion of starlight by atmospheric turbulence. For such a system installed on an 8-m-class telescope, the spatial resolution and sensitivity could be up to 100 times better than conventional imaging. Adaptive-optics corrections have hitherto been achieved only for regions of the sky within a few arcseconds of a bright reference source. But it has been proposed theoretically that by using multiple guide stars, the tomography of atmospheric turbulence could be probed and used to extend adaptive-optics corrections to the whole sky. Here we report the experimental verification of such tomographic corrections, using three off-axis reference stars approximately 15 arcsec from the central star. We used the observations of the off-axis stars to calculate the deformations of the wavefront of the central star, and then compare them with the real measured values. This tomographic approach is found to reduce variations in the wavefront by approximately 92%. Our result demonstrates that a serious barrier to achieving diffraction-limited seeing over the whole sky has been removed.

15.
Eur Rev Med Pharmacol Sci ; 14(10): 865-70, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21222373

RESUMEN

Herbal medicines are widely used in the world and are generally considered effective and safe, although many studies have demonstrated their potential toxic effects, particularly for the liver. We present a case of a woman, who developed a mixed cholestatic/hepatocellular liver injury due to herbal products. Firstly, she was admitted to Division of Surgery for right upper abdominal pain and jaundice and, for the suspect of biliary obstruction, she underwent to cholecystectomy. For persistence of liver enzymes elevation, she was admitted to our Gastroenterology Unit. We excluded every etiologies of hepatitis and, after an intensive dialogue with the patient, we obtained a history of herbal medicines use. Then, we performed a liver biopsy which was compatible with hepatotoxic injury. Therapy with ursodeoxycholic acid (UDCA) was started. Liver function tests returned to normal in two months. We describe this clinical case to encourage the communication doctor/patient in phytotherapy area and physician knowledge about efficacy and side effects of herbal medicine to avoid delayed diagnosis.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Medicamentos Herbarios Chinos/toxicidad , Fitoterapia/efectos adversos , Adulto , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Femenino , Humanos , Ácido Ursodesoxicólico/uso terapéutico
16.
J Fish Biol ; 76(5): 1117-27, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20409165

RESUMEN

Three species of cichlids belonging to the genus Symphysodon have demonstrated interspecific and intraspecific variation in nucleolus organizer regions (NOR) detected with silver nitrate. In order to understand the evolution of this marker in the genus, the structural variability of these sequences in mitotic chromosomes from Symphysodon aequifasciatus, Symphysodon discus and Symphysodon haraldi was investigated using both silver nitrate impregnation and hybridization of the 18S rRNA gene probe. For the three species, the two markers were intraspecifically and interspecifically variable both in the number and in the size of the sites. This polymorphism may stem from duplications and translocations, which suggests that structural chromosome rearrangements effectively act in the karyoevolution of wild Symphysodon species and may have favoured the adaptability of these fishes to diverse aquatic environments in the Amazon.


Asunto(s)
Cíclidos/genética , Evolución Molecular , Región Organizadora del Nucléolo/genética , ARN Ribosómico 18S/genética , Animales , Aberraciones Cromosómicas , Sondas de ADN , ADN Ribosómico/genética , Femenino , Marcadores Genéticos , Hibridación Fluorescente in Situ , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Tinción con Nitrato de Plata
17.
Eur Rev Med Pharmacol Sci ; 24(13): 7357-7365, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32706074

RESUMEN

OBJECTIVE: Liver transplant (LT) patients need regular follow-up both by ultrasonography and elastography. Shear wave elastography is now available in high-end ultrasound systems that, however, may yield different values for any given liver, reflecting technological differences. The aim of this study was to establish whether the point shear wave elastography QElaXto® (QEpSWE), available on Esaote (Genoa, Italy) systems, is comparable to the standard Fibroscan® (vibration-controlled transient elastography, VCTE) in the real-life setting of liver transplant (LT) patients. PATIENTS AND METHODS: We prospectively examined with QEpSWE 196 consecutive LT patients referred for VCTE and ultrasound examination. The agreement between QEpSWE and VCTE was assessed with Lin concordance correlation coefficient (CCC) and Bland-Altman analysis. The performance of QEpSWE was assessed with the ROC curves using the VCTE cut-offs of 7 and 12 kPa for F2-F3 and F4, respectively. RESULTS: The two methods showed 100% of successful and reliable liver stiffness measurements (LSM), similar median LSM in the whole group and in the two subgroups F2-F3 and F4 of fibrosis, with a disagreement in categorization of liver fibrosis in only 2% of cases, and never more than 1 stage of fibrosis. Further, they presented the same degree of higher LSMs in clinically unstable LT patients and an excellent overall agreement (CCC=0.91, accuracy=0.95, precision=0.96), even if agreement was less satisfactory in the range of severe fibrosis. The optimal cutoffs of QEpSWE were 6.7 and 11.6 kPa for F2-F3 and F4, respectively. CONCLUSIONS: The values of VCTE and QEpSWE showed a very high correlation in the staging of liver fibrosis. QEpSWE seems a promising method for staging liver fibrosis in LT patients.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Cirrosis Hepática/diagnóstico por imagen , Trasplante de Hígado , Anciano , Estudios Transversales , Femenino , Humanos , Cirrosis Hepática/etiología , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento
18.
Cytogenet Genome Res ; 127(1): 43-53, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20110656

RESUMEN

As part of a genetic screening program for wild Discus fishes, we analyzed karyotypes and cytogenetic characteristics of Symphysodon aequifasciatus, S. discus and S. haraldi using C-banding and fluorescent in situ hybridization (FISH) with the Rex3 retrotransposon and 5S rDNA probes in mitotic and meiotic chromosomes. In the 3 species, diploid chromosome number was 2n = 60 and karyotypes contained predominantly meta-submetacentric chromosomes. C-banding showed blocks of constitutive heterochromatin mainly in the pericentromeric region. Physical mapping of repetitive 5S rDNA sequences and Rex3 retrotransposons in mitotic and meiotic chromosomes showed partial colocalization of constitutive heterochromatin and repetitive elements. Correlations among the accumulation of repetitive elements, heterochromatinization and chromosome rearrangements have been hypothesized to explain the karyotype differentiation in the Symphysodon genus. The role of repetitive elements in adaptation to highly diverse habitats, as well as in the generation of the phenotypic and genetic variability found in wild Discus populations, needs to be further investigated.


Asunto(s)
Cromosomas , Cíclidos/genética , ADN Ribosómico/genética , Retroelementos/genética , Animales , Femenino , Cariotipificación , Masculino , Mapeo Físico de Cromosoma
19.
Cytogenet Genome Res ; 125(3): 224-34, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19738382

RESUMEN

Repeated DNA elements have been extensively applied as physical chromosome markers in comparative studies for the identification of chromosomal rearrangements, the identification of sex chromosomes, chromosome evolution analysis and applied genetics. Here, we report the characterization of the transposable elements (TE) Tc1, Rex1, Rex3 and Rex6 and a new element called RCk in the genome of the South American cichlid fish Cichla kelberi using nucleotide sequence analysis and hybridization to metaphase chromosomes. The analysis of the repeated elements demonstrated that they are, in most cases, compartmentalized in heterochromatic regions, as has been observed in several other vertebrates. On the other hand, the elements Rex1 and Rex3 were also observed spanning extensive euchromatic regions on 2 chromosome pairs. The RCk element exhibits a wide distribution among fishes and also in amphibians, and it was spread throughout the chromosomes of C. kelberi. Our results have demonstrated that the compartmentalization of repeated elements is not restricted to heterochromatic segments, which has provided new concepts with regard to the genomic organization of transposons.


Asunto(s)
Cíclidos/genética , Elementos Transponibles de ADN , Genoma , Animales , Cromosomas , Análisis Citogenético , ADN/química , ADN/genética , Filogenia , Mapeo Físico de Cromosoma , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
20.
Transplant Proc ; 51(1): 184-186, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30655123

RESUMEN

Annual dermatologic examination is required in all transplant recipients because of the high risk of skin cancers. Nevertheless, if the transplant recipient is merely advised to have a dermatologic consultation, the adherence usually appears to be poor. We analyzed our population of liver transplant recipients in 2 periods: in 2014 (group 1) and in 2016 (group 2), when we had organized the presence of a dermatologist at scheduled intervals to annually examine the entire liver transplant population we actively follow-up. The adherence to dermatologic screening during period 1 was significantly lower (50/179; 28% of patients) than during period 2 (198/200; 99% of patients) (P < .0001). In group 1 and 2, respectively, we found cutaneous lesions in 3 of 50 (6%) and in 13 of 198 (7%) examined patients and in 3 of 179 (1.7%) and in 13 of 200 (6.5%) of the whole groups of patients in follow-up (P = .02). The type of neoplastic lesions found at dermatologic visits were similar in group 1 (1 squamous cell carcinoma, 1 basal cell carcinoma) and group 2 (2 squamous cell carcinoma, 3 basal cell carcinoma) (P = .45), but with this intensive protocol of surveillance we discovered more preneoplastic lesions (1 leukoplakia in group 1 vs 7 actinic keratosis and 1 dysplastic nevus in group 2; P = .03). These results suggest that the planned presence of a dermatologist is mandatory among the many aspects of a well-organized transplant follow-up team.


Asunto(s)
Trasplante de Hígado/efectos adversos , Tamizaje Masivo/métodos , Cooperación del Paciente , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/etiología , Receptores de Trasplantes , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
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