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1.
Phys Med ; 83: 184-193, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33798904

RESUMEN

PURPOSE: To develop a computerized detection system for the automatic classification of the presence/absence of mass lesions in digital breast tomosynthesis (DBT) annotated exams, based on a deep convolutional neural network (DCNN). MATERIALS AND METHODS: Three DCNN architectures working at image-level (DBT slice) were compared: two state-of-the-art pre-trained DCNN architectures (AlexNet and VGG19) customized through transfer learning, and one developed from scratch (DBT-DCNN). To evaluate these DCNN-based architectures we analysed their classification performance on two different datasets provided by two hospital radiology departments.DBT slice images were processed following normalization, background correction and data augmentation procedures. The accuracy, sensitivity, and area-under-the-curve (AUC) values were evaluated on both datasets, using receiver operating characteristic curves. A Grad-CAM technique was also implemented providing anindication of the lesion position in the DBT slice. RESULTS: Accuracy, sensitivity and AUC for the investigated DCNN are in-line with the best performance reported in the field. The DBT-DCNN network developed in this work showed an accuracy and a sensitivity of (90% ± 4%) and (96% ± 3%), respectively, with an AUC as good as 0.89 ± 0.04. Ak-fold cross validation test (withk = 4) showed an accuracy of 94.0% ± 0.2%, and a F1-score test provided a value as good as 0.93 ± 0.03. Grad-CAM maps show high activation in correspondence of pixels within the tumour regions. CONCLUSIONS: We developed a deep learning-based framework (DBT-DCNN) to classify DBT images from clinical exams. We investigated also apossible application of the Grad-CAM technique to identify the lesion position.


Asunto(s)
Neoplasias de la Mama , Aprendizaje Profundo , Área Bajo la Curva , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Mamografía , Redes Neurales de la Computación , Curva ROC
2.
Int J Immunopathol Pharmacol ; 26(3): 773-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24067476

RESUMEN

The treatment choice for metastatic breast cancer should consider the appropriate balance between efficacy and toxicity of the therapy. We discuss a clinical case with an early response and prolonged to liposomal anthracyclines-based chemotherapy, without cardiotoxicity, enhancing the evidence of safety of liposomal formulation to prevent heart damage. Moreover, the case seems to be of interest for the role of 18F-FDG-PET in clinical response assessment: an early decrease of the standardized uptake value value, even before conventional imaging evaluation, is highly predictive for prolonged clinical response.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/tratamiento farmacológico , Antibióticos Antineoplásicos/administración & dosificación , Antineoplásicos Alquilantes/administración & dosificación , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/diagnóstico por imagen , Carcinoma Ductal de Mama/secundario , Ciclofosfamida/administración & dosificación , Progresión de la Enfermedad , Doxorrubicina/administración & dosificación , Doxorrubicina/análogos & derivados , Femenino , Fluorodesoxiglucosa F18 , Humanos , Persona de Mediana Edad , Imagen Multimodal , Polietilenglicoles/administración & dosificación , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Radiofármacos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
3.
Eur J Clin Microbiol Infect Dis ; 31(11): 3139-44, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22735899

RESUMEN

The diagnosis of catheter-related bloodstream infections (CRBSIs) in febrile patients with indwelling central venous catheters (CVCs) needs improvement. To diagnose CRBSIs more efficiently, we have developed a novel culture approach using the catheter tips removed from febrile patients. CVCs and blood cultures from 1,070 patients with only CVC-related infections were obtained over a period of 3 years (January 2009 to December 2011). The CVCs were evaluated by a semi-quantitative catheter culture method according to Maki's method and by our novel method, which is based on the use of the HB&L UROQUATTRO™ system (Alifax, Padova, Italy). Using our new method, 571 (571/1,070) of the infections were confirmed as CRBSIs. The remaining 487 patients had infections that were associated with hematologic malignancies, neutropenia, prior exposure to antibiotics, and a decreased CVC removal rate. Twelve samples were identified as false-positives. The percentage of patients with CRBSIs confirmed using the HB&L UROQUATTRO™ system was 53.36 % versus 34.95 % (p-value 0.004) using Maki's method (374/1,070 CVC Maki-positive samples). Our results indicate that our new culture method allows for an improved CRBSI diagnosis rate. A significant number of tip cultures (18.41 %) tested positive for CRBSIs using our system but were negative when tested using Maki's method. Moreover, the use of the HB&L UROQUATTRO™ system allowed us to significantly reduce diagnosis time; a negative CRBSI diagnosis could be made within 6 h and a positive diagnosis could be made within 22-28 h.


Asunto(s)
Infecciones Relacionadas con Catéteres/diagnóstico , Catéteres Venosos Centrales/efectos adversos , Técnicas Microbiológicas/métodos , Sepsis/diagnóstico , Errores Diagnósticos/estadística & datos numéricos , Humanos , Factores de Tiempo
4.
Minerva Cardioangiol ; 59(3): 271-84, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21516075

RESUMEN

Chronic total occlusion (CTO) is a common finding on diagnostic coronary angiography and represents one of the most challenging lesion subset in interventional cardiology. The introduction of dedicated guidewires and the development of new techniques have led to improve the success rate in the crossing of CTO lesion while the use of bare metal stent first, and, then, the use of drug eluting stent (DES) have significantly reduced the occurrence of restenosis and the need for target lesion revascularization in short and mid-term follow-up after CTO recanalization. However, new unsolved issues about the use of DES in CTO, that might impact long-term outcome, are emerging. The aim of this article is to review the current stage of knowledge on the application of stents in the treatment of CTO, with a particular attention to DES use and to DES-related challenges.


Asunto(s)
Oclusión Coronaria/terapia , Stents Liberadores de Fármacos , Angioplastia Coronaria con Balón , Enfermedad Crónica , Angiografía Coronaria , Oclusión Coronaria/diagnóstico , Reestenosis Coronaria/prevención & control , Medicina Basada en la Evidencia , Humanos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Stents , Resultado del Tratamiento
5.
Genome ; 51(9): 705-13, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18772948

RESUMEN

Three clones containing satellite DNA sequences were selected from a randomly sheared genomic DNA library of Picea abies (clones PAF1, PAG004P22F (2F), and PAG004E03C (3C)). PAF1 contained 7 repeats that were 37-55 bp in length and had 68.9%-91.9% nucleotide sequence similarity. Two 2F repeats were 305-306 bp in length and had 83% sequence similarity. Two 3C repeats were 193-226 bp in length and had a sequence similarity of 78.6%. The copy number per 1C DNA of PAF1, 2F, and 3C repeats was 2.7 x 10(6), 2.9 x 10(5), and 2.9 x 10(4), respectively. In situ hybridization showed centromeric localization of these sequences in two chromosome pairs with PAF1, all pairs but one with 2F, and three pairs with 3C. Moreover, PAF1 sequences hybridized at secondary constrictions in six pairs, while 2F-related sequences were found at these chromosome regions only in four pairs. These hybridization patterns allow all chromosome pairs to be distinguished. PAF1-related repeats were contained in the intergenic spacer (IGS) of ribosomal cistrons in all six nucleolar organizers of the complement, while sequences related to 2F were found on only one side of the rDNA arrays in four pairs, showing structural diversity between rDNA regions of different chromosomes.


Asunto(s)
Cromosomas de las Plantas , ADN Satélite/genética , Picea/genética , Secuencia de Bases , Southern Blotting , Centrómero , Hibridación Fluorescente in Situ , Cariotipificación , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico
6.
J Hosp Infect ; 66(3): 262-8, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17544166

RESUMEN

Even with good surveillance programmes, hospital-acquired infections (HAIs) are not always recognized and this may lead to an outbreak. In order to reduce this risk, we propose a model for prompt detection of HAIs, based on the use of a real-time epidemiological information system called VIGI@ct (bioMèrieux, Las Balmas, France) and on the rapid confirmation or exclusion of the genetic relationship among pathogens using fluorescent amplified length fragment polymorphism (f-AFLP) microbial fingerprinting. We present the results of one year's experience with the system, which identified a total of 306 suspicious HAIs. Of these, 281 (92%) were 'confirmed' by clinical evidence, 16 (5%) were considered to be simple colonization and the latter nine (3%) were archived as 'not answered' because of the absence of the physician's cooperation. There were seven suspected outbreaks; of these, f-AFLP analysis confirmed the clonal relationship among the isolates in four cases: outbreak 1 (four isolates of Pseudomonas aeruginosa), outbreak 2 (three Escherichia coli isolates), outbreak 6 (two Candida parapsilosis isolates) and outbreak 7 (30 ESbetaL-producing Klebsiella pneumoniae subsp. pneumoniae). Based on our results, we conclude that the combination of VIGI@ct and f-AFLP is useful in the rapid assessment of an outbreak due to Gram-positive or Gram-negative bacteria and yeasts.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Infección Hospitalaria/diagnóstico , Brotes de Enfermedades/prevención & control , Control de Infecciones/métodos , Sistemas de Registros Médicos Computarizados , Infección Hospitalaria/prevención & control , Genotipo , Humanos , Unidades de Cuidados Intensivos , Italia , Polimorfismo de Longitud del Fragmento de Restricción , Vigilancia de Guardia
7.
Genome ; 49(1): 64-72, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16462902

RESUMEN

Two repeated DNA sequences, pHaS13 and pHaS211, which revealed similarity to the int gene of Ty3-gypsy retrotransposons and the RNAse-H gene of Ty1-copia retroelements, respectively, were surveyed in Asteraceae species and within the genus Helianthus. Southern analysis of the genome of selected Asteraceae that belong to different tribes showed that pHaS13- and pHaS211-related subfamilies of gypsy- and copia-like retroelements are highly redundant only in Helianthus and, to a lesser extent, in Tithonia, a Helianthus strict relative. However, under low stringency posthybridization washes, bands were observed in almost all the other Asteraceae tested when pHaS13 was used as a probe, and in several species when pHaS211 was hybridized. FISH analysis of pHaS13 or pHaS211 probes was performed in species in which labelling was observed in Southern hybridizations carried out under high stringency conditions (Helianthus annuus, Tithonia rotundifolia, Ageratum spp., Leontopodium spp., Senecio vulgaris for pHaS13, and H. annuus, Tithonia rotundifolia, and S. vulgaris for pHaS211). Scattered labelling was observed over all metaphase chromosomes, indicating a large dispersal of both Ty3-gypsy- and Ty1-copia-like retroelements. However, preferential localization of Ty3-gypsy-like sequences at centromeric chromosome regions was observed in all of the species studies but one, even in species in which pHaS13-related elements are poorly represented. Ty1-copia-like sequences showed preferential localization at the chromosome ends only in H. annuus. To study the evolution of gypsy- and copia-like retrotransposons in Helianthus, cladograms were built based on the Southern blot hybridization patterns of pHaS13 or pHaS211 sequences to DNA digests of several species of this genus. Both cladograms agree in splitting the genomes studied into annuals and perennials. Differences that occurred within the clades of perennial and annual species between gypsy- and copia-like retroelements indicated that these retrotransposons were differentially active during Helianthus speciation, suggesting that the evolution of the 2 retroelement families was, within limits, independent.


Asunto(s)
Asteraceae/clasificación , Asteraceae/genética , Helianthus/clasificación , Helianthus/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Secuencia de Aminoácidos , Evolución Molecular , Datos de Secuencia Molecular
8.
Cytogenet Genome Res ; 109(1-3): 385-92, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15753601

RESUMEN

Genomic in situ hybridization was used to study Triticum x Dasypyrum wide hybrids and derived lines. A cytogenetic investigation was carried out in progenies of (i) amphiploids derived from T. turgidum var. durum (T. durum; 2n = 14; genomes AABB) x D. villosum (2n = 14; genome VV), (ii) three-parental hybrids (T. durum x D. villosum) x T. aestivum (2n = 42, genomes A'A'B'B'D'D'), and (iii) T. aestivum aneuploid lines carrying D. villosum chromosomes or chromatin. The amphiploids derived from T. durum x D. villosum showed a stable chromosomal constitution, made up of 14 V chromosomes, 14 chromosomes carrying the wheat A genome and 14 chromosomes carrying the B genome. High karyological instability was observed in the progenies of three-parental hybrids ([T. durum x D. villosum] x T. aestivum). Plants having the expected 14 A chromosomes, 14 B chromosomes, 7 D chromosomes, and 7 V chromosomes were rather rare (4.5%). Many progeny plants (45.5%) had the hexaploid wheat genome with 42 chromosomes and lacked any detectable D. villosum chromatin. Other plants (50%) had 14 A chromosomes and 14 B chromosomes, plus variable numbers of D and V chromosomes, the former being better retained than the latter in most cases. Some T. aestivum lines carrying D. villosum chromosomes or chromatin, as the result of addition, substitution, or recombination events or even a combination of these karyological events, were found to be stable. Other lines were unstable, and these lines carried 1V, 3V, or 5V chromosomes or their portions. Substitution or recombination events where 1V chromosomes were involved could concern the homeologous counterparts in both the A and B and D genomes of wheat. No line could be recovered where the shorter arm of 3V chromosomes was present. Changes in the morphology and banding pattern of V chromosomes were observed in hybrids that did not carry the entire D. villosum complement. By comparing the results of our cytogenetic analyses with certain phenotypic characteristics of the lines studied, genes for discrete traits could be assigned to specific V chromosomes or V chromosome arms. From the frequency of V chromosomes that were involved in chromatin exchanges with or substituted for one of their homeologous counterparts in the A, B, and D wheat genomes, it was inferred that D. villosum belongs to the same phyletic lineage as T. urartu (donor of the A genome of wheat) and Aegilops speltoides (B genome), and that Ae. squarrosa (D genome) diverged earlier from D. villosum.


Asunto(s)
Poaceae/genética , Triticum/genética , Cromosomas de las Plantas/genética , Cromosomas de las Plantas/ultraestructura , Cruzamientos Genéticos , ADN de Plantas/genética , ADN de Plantas/aislamiento & purificación , Hibridación Genética , Cariotipificación , Ploidias
9.
Int J Rehabil Res ; 26(4): 313-6, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14634367

RESUMEN

The purpose of this study was to explore intra-individual variability of global self-esteem and physical self-worth in adolescents with spina bifida (n = 3). Three adolescents were assessed in their schools by auto-evaluation over a period of 12 weeks (three times a week) with the Physical Self Inventory-6, a six-item questionnaire with a visual analogue scale. Statistical analyses included auto-correlation function (ACF) for studying the time series. Descriptive statistics demonstrated that in all the dimensions of physical self and global self-esteem, participants showed great variability over time. Auto-correlation function indicated 20 non-stationary and unstable time series, and four stationary time series. The non-stationary evolution of physical self, and global self-esteem in the three adolescents with spina bifida studied may explain the absence of consensus in the literature on the level of the self-perception. Future longitudinal research needs to be engaged.


Asunto(s)
Autoimagen , Disrafia Espinal/psicología , Adolescente , Femenino , Humanos , Estudios Longitudinales , Masculino , Encuestas y Cuestionarios
10.
Sci China C Life Sci ; 46(1): 104-12, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20213367

RESUMEN

Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36-42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30-36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1-4 pairs of the O.violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29-34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1-3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromosome complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.


Asunto(s)
Brassica/genética , Aneuploidia , Brassicaceae/genética , ADN de Plantas/genética , Genoma de Planta , Homocigoto , Hibridación Genética , Hibridación in Situ , Planta de la Mostaza/genética
11.
Chromosoma ; 111(3): 192-200, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12355209

RESUMEN

Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.


Asunto(s)
Helianthus/genética , Retroelementos , Secuencia de Aminoácidos , Mapeo Cromosómico , Evolución Molecular , Dosificación de Gen , Datos de Secuencia Molecular , Alineación de Secuencia
12.
Chromosome Res ; 8(7): 615-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11117357

RESUMEN

The chromosome complement of olive (Olea europaea L.) has been characterized by differential staining of the chromatin and chromosomal localization of highly repeated DNA sequences and ribosomal cistrons. DAPI staining produces different-sized positive bands in various locations on all the chromosomes. By combining this band pattern with the results obtained from cytological hybridization of OeTaq80, OeTaq178, and OeGEM86 DNA tandem repeats, most of the pairs can be distinguished from each other, in spite of the large number of chromosomes (2n = 46), their small size and similar morphology. Different tandem-repeated DNA sequences may be contained into single heterochromatic chromosome regions, even though there are regions where repeats of only one family are present. OeTaq80- and OeGEM86-related DNA sequences are rather specific to the heterochromatin at the chromosome ends, while most sequences related to the longer OeTaq178 probe are confined to interstitial heterochromatin. Some exceptions suggest that major chromosomal rearrangements occurred during genome evolution. Polymorphism, which may differentiate olive cultivars, was observed within chromosome pairs I, V, and VII.


Asunto(s)
Cromosomas , Magnoliopsida/genética , Secuencias Repetidas en Tándem , Cromatina/ultraestructura , Bandeo Cromosómico , Cromosomas/química , Cromosomas/genética , Cromosomas/ultraestructura , Colorantes Fluorescentes , Hibridación in Situ , Indoles , Cariotipificación , Metafase
13.
Radiol Med ; 100(1-2): 33-6, 2000.
Artículo en Italiano | MEDLINE | ID: mdl-11109449

RESUMEN

PURPOSE: US is usually considered of little help in studying the ureters because it only shows proximal and distal tracts. The distal ureter is also difficult to study with most of the other imaging methods. Transrectal probes improve depiction of the intramural and pelvic tracts of the ureter, as well as image quality, dramatically providing good results in a short time. The first and, to our knowledge, the only report on this procedure has been Holm's (1994), where the author reported good results though in a small series. For years we have used transrectal US, performed for prostate studies, also to examine intramural ureters and have obtained good results in a short time. Thus we decided to compare the transrectal with the transabdominal approach. MATERIAL AND METHODS: We examined 92 randomly selected male patients with various urologic conditions but no ureter involvement using 3.5 MHz convex and 5.0 MHz biplane transrectal probes. Image quality was rated on an arbitrary scale (0-4) and then submitted to statistical analysis. RESULTS: Transrectal images were clearly superior to transabdominal ones (p = 0.012) and particularly, ureters were depicted in 93% versus 60% of cases, respectively. The amount of urine in the bladder appears to play a major role (the greater the amount the worse the image quality), while ureter depiction is independent of body habit and bladder squeezing. CONCLUSIONS: Our results are clearly superior to Holm's. Also, considering that the transrectal examination requires a short time, is cost-effective and little invasive, we believe that this method can play an extremely important role in lower ureter studies.


Asunto(s)
Uréter/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sínfisis Pubiana , Recto , Ultrasonografía/instrumentación , Ultrasonografía/métodos , Enfermedades Ureterales/diagnóstico por imagen
14.
Chromosoma ; 108(5): 317-24, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10525968

RESUMEN

A family of repeated DNA sequences of about 1200 bp in length and bordered by well-conserved, 18 bp inverted repeats (VfB family) was found in the nuclear genome of Vicia faba. The structure, chromosomal organization, redundancy modulation and evolution of these sequences were investigated. They are enriched in A+T base pairs (about 40% G+C) and lack any obvious internally repeated motif. A 64%-73% nucleotide sequence identity was found when pairwise comparisons between VfB sequences were carried out (average 69%). Direct repeats were not found to flank the inverted repeats that border these DNA sequences. The results obtained by hybridizing VfB repeats to Southern blots of V. faba genomic DNA digested with EcoRI indicated that these DNA elements are interspersed in the genome. The appearance of bands in these Southern blots and comparison of the structure of the sequences that flank different VfB elements showed that these repeats might be part of other, longer repeated DNA sequences. A high degree of dispersion throughout the genome was confirmed by cytological hybridization, which showed VfB sequences to be scattered along the length of all chromosomes and to be absent or rare only at heterochromatic chromosomal regions. These sequences contribute to intraspecific alterations of genomic size. Indeed, dot-blot hybridizations proved that their redundancy, which is positively correlated with the overall amount of nuclear DNA in each accession, varies between V. faba land races (27x10(3)-230x10(3) copies per 1C DNA). Southern blot hybridization of VfB repeats to restriction endonuclease-digested genomic DNAs of V. faba, V. narbonensis, V. sativa, Phaseolus coccineus, Populus deltoides, and Triticum durum revealed nucleotide sequence homology of these DNA elements, whatever the stringency conditions, only to the DNAs of Vicia species, and to a reduced extent to the DNAs of V. narbonensis and V. sativa compared with that of V. faba. It is concluded that VfB repeats might be descended from mobile DNA elements and contribute to change genomic size and organization during evolution.


Asunto(s)
Cromosomas/genética , ADN de Plantas/genética , ADN Satélite/genética , Fabaceae/genética , Plantas Medicinales , Composición de Base , Emparejamiento Base , Secuencia de Bases , Mapeo Cromosómico , Cromosomas/ultraestructura , Evolución Molecular , Fabaceae/clasificación , Genoma de Planta , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
15.
Heredity (Edinb) ; 83 ( Pt 2): 188-95, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10469207

RESUMEN

The amount and spatial organization of the heterochromatin in nuclei of the shoot meristem and the frequency in the nuclear DNA of sequences belonging to a family of tandem repeats were investigated in cultivars of Olea europaea and related species. Significant differences between Olea species and between cultivars of O. europaea were observed: (i) in the spatial organization of the heterochromatin in interphase nuclei as determined by the number and surface area of the chromocentres; (ii) in genome size; and (iii) in the amount of condensed chromatin as measured by cytophotometry carried out at different thresholds of optical density. DNA elements belonging to a family of tandem repeats about 80 bp in length (OeTaq80 repeats) were isolated from the genomic DNA of an olive cultivar. It was shown: (i) by nucleotide sequence comparisons, that these repeats display variability in structure even within the same array, where different elements may share no more than 74% homology; (ii) by in situ hybridization, that OeTaq80-related DNA sequences are mainly localized in the heterochromatin at the chromosome ends; (iii) by dot-blot hybridization experiments, that these sequences are highly represented in the genome of all the olive cultivars and the majority of Olea species studied, and that their frequency may differ significantly even between olive cultivars; and (iv) by calculating the copy number of OeTaq80-related sequences per haploid (1C) genome, that the redundancy of these DNA elements may differ significantly between the genomes tested. It is suggested that the inter- and intraspecific changes in the nuclear and genomic traits observed can contribute to the understanding of the phylogenetic relationships between Olea species and in defining parameters to be exploited in varietal identification within cultivated olives.


Asunto(s)
Frutas/genética , Heterocromatina/química , Secuencia de Bases , Núcleo Celular/química , Citofotometría , ADN de Plantas , Evolución Molecular , Genes de Plantas , Datos de Secuencia Molecular , Brotes de la Planta/química , Especificidad de la Especie , Secuencias Repetidas en Tándem
16.
Dig Surg ; 15(1): 30-4, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9845560

RESUMEN

BACKGROUND/AIMS: The surgical treatment of duodenogastric reflux (DGR), resistant to medical therapy, in patients with intact stomach is difficult to standardize. The aim of this study is to present our experience on 5 patients, all cholecystectomized, with severe DGR disease treated surgically. METHODS: Out of a group of 223 patients suffering from nonulcerous dispeptic pathology presenting to our department, we selected 5 patients suffering from alkaline reflux gastritis in intact stomach. The diagnosis of primary DGR was made using Wilson's criteria. The surgical procedure adopted consisted of a truncal vagotomy, antrectomy, and a Roux-en-Y gastrojejunostomy. RESULTS: No perioperative mortality was observed. Twelve months after surgery all patients expressed satisfaction with the result of the operation and complained of no severe disturbances. A sense of postprandial fullness with a sense of pain in the left shoulder persisted in one case only, requiring the consumption of small and frequent meals. Radiological examination of the upper gastrointestinal tract of these patients showed notably delayed emptying of the gastric stump, while the endoscopic picture was completely normal. CONCLUSION: The antrectomy and Roux-en-Y gastrojejunostomy is a better known operation, easily executed, and has the advantage that it can be performed on patients previously operated on for gastric resection and therefore suffering from secondary reflux. It also has the advantage of removing the gastric antrum where mucous atrophy is more frequent and is susceptible to neoplastic degeneration. However, at the present time the choice between different types of operation depends exclusively on the personal conviction and experience of the surgeon.


Asunto(s)
Reflujo Duodenogástrico/cirugía , Yeyuno/cirugía , Estómago/cirugía , Vagotomía Troncal , Anastomosis en-Y de Roux , Colecistectomía/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antro Pilórico/cirugía
17.
J Surg Oncol ; 68(1): 48-50, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9610663

RESUMEN

BACKGROUND AND OBJECTIVES: Chemotherapy and radiotherapy have been investigated in several studies about their role in primary (neoadjuvant) treatment before surgery in breast cancer. We proposed a pilot study to evaluate a primary scheme of alternate radio-chemotherapy in the treatment of operable (T2- small T3) breast cancer. METHODS: 14 patients were recruited. Cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) were administered on days 1 and 8, every 4 wk, for two cycles. Radiotherapy was administered during the 3rd and 4th wk (5 d/wk) after the beginning of chemotherapy. The patients were operated on within 24 wk. All the patients received four additional cycles of chemotherapy within 1 mo after surgery. RESULTS: We observed: 1 (8.3%) complete remission (CR), 8 (66.7%) partial remission (PR), 3 (25%) stationary disease (SD); no progressive disease was observed. Modified radical mastectomy was performed on 7 patients (58.3%). Conservative surgery was performed on 5 cases (41.7%). No major complications were observed. No patient has shown local or distant recurrence. CONCLUSIONS: This study shows the feasibility of a primary chemoradiotherapy treatment for breast cancer. But to evaluate the impact of this therapy on overall survival and recurrence risk and its possible introduction in clinical practice, we need larger series and longer follow-up.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/terapia , Mastectomía Radical Modificada , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Terapia Combinada , Esquema de Medicación , Estudios de Factibilidad , Femenino , Fluorouracilo/administración & dosificación , Humanos , Metotrexato/administración & dosificación , Persona de Mediana Edad , Proyectos Piloto , Dosificación Radioterapéutica
18.
Radiol Med ; 91(3): 231-7, 1996 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-8628936

RESUMEN

The normal laryngeal and perilaryngeal structures (neither nodal nor vascular) of 120 healthy and informed volunteers and of 46 patients with extralaryngeal neck conditions were studied with ultrasonography (US). The study was performed with a high-frequency linear probe on the transverse and sagittal planes; the patients were examined supine, with neck hyperextension, during quiet breathing, in inspiratory and expiratory breath-holding, during Valsalva maneuver or phonation. Axial scans clearly depict, in cranio-caudal direction, the base of the tongue, the hyoid and adjacent muscular structures. At the laryngeal vestibule epiglottis is always clearly demonstrated as a thin hypoechoic curvilinear rim and the pre-epiglottic space as a fat-filled and markedly echogenic structure. Pyriform sinuses are more difficult to study with US and should therefore be always distended by air during Valsalva because no suitable US contrast agent is available for their exploration yet. The ossification of thyroid laminae prevents or hinders the exploration of endolaryngeal structures because of consequent posterior acoustic shadow. In case of partial ossification or cartilaginous thyroid laminae, paraglottic spaces are easily demonstrated with US, as well as the false cords and, partially, arytenoids and posterior laryngeal wall muscles. The muscular structure of the true cords, their mobility in the M-mode and, in half of the cases, the thin vocal plicae joining anteriorly in the anterior commissure, are easily depicted with US. To conclude, US permits to demonstrate normal laryngeal anatomy by a quick and harmless examination in several breathing and phonation phases, which is an essential premise to the correct interpretation of abnormal US findings.


Asunto(s)
Laringe/diagnóstico por imagen , Adolescente , Adulto , Anciano , Niño , Preescolar , Epiglotis/anatomía & histología , Epiglotis/diagnóstico por imagen , Femenino , Humanos , Hueso Hioides/anatomía & histología , Hueso Hioides/diagnóstico por imagen , Músculos Laríngeos/anatomía & histología , Músculos Laríngeos/diagnóstico por imagen , Laringe/anatomía & histología , Masculino , Persona de Mediana Edad , Valores de Referencia , Ultrasonografía/instrumentación , Ultrasonografía/métodos , Pliegues Vocales/anatomía & histología , Pliegues Vocales/diagnóstico por imagen
19.
Genome ; 38(6): 1255-61, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8654919

RESUMEN

Tandemly repeated DNA sequences about 60 bp in length, which may be isolated by digestion with FokI restriction endonuclease, were studied by means of molecular and cytological hybridization in Vicia faba and other Vicia species. The results obtained can be summarized as follows: (i) FokI repeats are almost species specific to V. faba, since they hybridize to a minimum extent to genomic DNA of only two out of five related species; (ii) these tandemly repeated elements display variability in structure even within one and the same array, where different repeats may share not more than 71% homology; (iii) their redundancy in the genome of V. faba is remarkably high and varies largely between land races (copy numbers per haploid, 1C, genome range from 21.51 x 10(6) to 5.39 x 10(6)); (iv) FokI repeats are clustered in differing amounts in each subtelocentric pair of the chromosome complement and are missing or present in a nondetectable amount in the submetacentric pair; (vi) chromosome regions that bear these repeats associate closely to varying degrees in interphase nuclei. These results are discussed in relation to possible functional roles that tandemly repeated DNA sequences such as the FokI elements might play.


Asunto(s)
Mapeo Cromosómico , Fabaceae/genética , Genoma de Planta , Plantas Medicinales , Secuencias Repetitivas de Ácidos Nucleicos/genética , Secuencia de Bases , Clonación Molecular , ADN de Plantas/genética , ADN de Plantas/aislamiento & purificación , Desoxirribonucleasas de Localización Especificada Tipo II , Dosificación de Gen , Hibridación in Situ , Interfase , Metafase , Datos de Secuencia Molecular , Raíces de Plantas , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
20.
Int Surg ; 80(1): 75-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7657498

RESUMEN

On 673 consecutive patients, excisional biopsy was performed on an outpatient basis using local anesthesia when a palpable breast lump was thought to be benign on clinical, mammographic and cytologic grounds (213 cases) or when the suspicion of cancer was low (100 cases). General anesthesia was performed when the mass was considered to be malignant or highly suspicious for cancer (360 cases). The percentage of correct preoperative diagnosis of benignancy was 96.2% (12 cancers in the outpatient group) and that of malignancy was 98.1% (7 benign lesions in the inpatient group). These data indicate that in the absence of malignant or highly suspicious preoperative findings breast biopsy should be performed under local anesthesia: it is a safe and more economical procedure in terms of medical costs, surgeon's time and patient's anxiety. On 60 patients breast biopsy was performed for non palpable breast lesions detected by mammography. Nineteen cancers were found (35%): the highest percentage was in stellate opacities and in highly suspicious microcalcifications (positive predictive value-PPV-of 45% and 50%, respectively). No cancer was detected in low density masses and in non suspicious calcifications: so, in such patients biopsy should not be recommended for the unacceptable overall biopsy cost.


Asunto(s)
Biopsia/métodos , Neoplasias de la Mama/diagnóstico , Mama/patología , Adulto , Anciano , Anestesia General , Anestesia Local , Biopsia/economía , Femenino , Humanos , Persona de Mediana Edad
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