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1.
Hum Reprod ; 34(6): 966-977, 2019 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-31111889

RESUMEN

STUDY QUESTION: Is it feasible to disseminate testicular tissue cryopreservation with a standardized protocol through a coordinated network of centers and provide centralized processing/freezing for centers that do not have those capabilities? SUMMARY ANSWER: Centralized processing and freezing of testicular tissue from multiple sites is feasible and accelerates recruitment, providing the statistical power to make inferences that may inform fertility preservation practice. WHAT IS KNOWN ALREADY: Several centers in the USA and abroad are preserving testicular biopsies for patients who cannot preserve sperm in anticipation that cell- or tissue-based therapies can be used in the future to generate sperm and offspring. STUDY DESIGN, SIZE, DURATION: Testicular tissue samples from 189 patients were cryopreserved between January 2011 and November 2018. Medical diagnosis, previous chemotherapy exposure, tissue weight, and presence of germ cells were recorded. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human testicular tissue samples were obtained from patients undergoing treatments likely to cause infertility. Twenty five percent of the patient's tissue was donated to research and 75% was stored for patient's future use. The tissue was weighed, and research tissue was fixed for histological analysis with Periodic acid-Schiff hematoxylin staining and/or immunofluorescence staining for DEAD-box helicase 4, and/or undifferentiated embryonic cell transcription factor 1. MAIN RESULTS AND THE ROLE OF CHANCE: The average age of fertility preservation patients was 7.9 (SD = 5) years and ranged from 5 months to 34 years. The average amount of tissue collected was 411.3 (SD = 837.3) mg and ranged from 14.4 mg-6880.2 mg. Malignancies (n = 118) were the most common indication for testicular tissue freezing, followed by blood disorders (n = 45) and other conditions (n = 26). Thirty nine percent (n = 74) of patients had initiated their chemotherapy prior to undergoing testicular biopsy. Of the 189 patients recruited to date, 137 have been analyzed for the presence of germ cells and germ cells were confirmed in 132. LIMITATIONS, REASONS FOR CAUTION: This is a descriptive study of testicular tissues obtained from patients who were at risk of infertility. The function of spermatogonia in those biopsies could not be tested by transplantation due limited sample size. WIDER IMPLICATIONS OF THE FINDINGS: Patients and/or guardians are willing to pursue an experimental fertility preservation procedure when no alternatives are available. Our coordinated network of centers found that many patients request fertility preservation after initiating gonadotoxic therapies. This study demonstrates that undifferentiated stem and progenitor spermatogonia may be recovered from the testicular tissues of patients who are in the early stages of their treatment and have not yet received an ablative dose of therapy. The function of those spermatogonia was not tested. STUDY FUNDING/COMPETING INTEREST(S): Support for the research was from the Eunice Kennedy Shriver National Institute for Child Health and Human Development grants HD061289 and HD092084, the Scaife Foundation, the Richard King Mellon Foundation, the Departments of Ob/Gyn & Reproductive Sciences and Urology of the University of Pittsburgh Medical Center, United States-Israel Binational Science Foundation (BSF), and the Kahn Foundation. The authors declare that they do not have competing financial interests.


Asunto(s)
Criopreservación , Preservación de la Fertilidad/métodos , Infertilidad Masculina/terapia , Testículo , Adolescente , Adulto , Factores de Edad , Antineoplásicos/efectos adversos , Biopsia , Niño , Preescolar , Preservación de la Fertilidad/normas , Enfermedades Hematológicas/complicaciones , Enfermedades Hematológicas/terapia , Humanos , Infertilidad Masculina/etiología , Masculino , Neoplasias/complicaciones , Neoplasias/terapia , Radioterapia/efectos adversos , Recuento de Espermatozoides , Recuperación de la Esperma , Espermatogonias/fisiología , Adulto Joven
2.
Klin Monbl Augenheilkd ; 232(4): 446-51, 2015 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-25902095

RESUMEN

BACKGROUND: Surgical management of large-angle infantile esotropia and decompensated microtropia has been controversially debated. There seems to be a relative bias against surgery on more than two horizontal muscles to avoid overcorrections. In our study we report on the sensory and motor outcomes after three horizontal muscle surgery. Furthermore we aim to suggest a table to guide surgery amounts. PATIENTS AND METHODS: This study was a retrospective interventional cohort of 27 patients (16 female, 11 male; mean age 7.9 [years], ranging from 1 to 27 [years]) with infantile esotropia and decompensated microtropia who underwent three horizontal muscle surgery (bilateral medial rectus muscle recession and lateral rectus muscle plication) between 2005 and 2013. RESULTS: Preoperative deviation in primary position measured 30.2 [°] (mean; range 21.9 to 48.0). Postoperatively esotropia was significantly reduced to 2.6 [°] (mean; range -16.7 to 16.7). After six months deviation measured 5.5 [°] (mean, range -14.1 to 21.9). An effect of 1.63°/mm was calculated for the combined three muscle surgery. CONCLUSIONS: For the correction of large-angle infantile esotropia and decompensated microtropia three horizontal muscle surgery is associated with a high success rate. Only a very low rate of consecutive exotropia does occur.


Asunto(s)
Esotropía/economía , Esotropía/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Músculos Oculomotores/cirugía , Procedimientos Quirúrgicos Oftalmológicos/métodos , Procedimientos de Cirugía Plástica/métodos , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
4.
Klin Monbl Augenheilkd ; 229(4): 357-61, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22496003

RESUMEN

BACKGROUND: The aim of this study was to describe the clinical characteristics and surgical outcome of acquired comitant non-accommodative esotropia without obvious cause in children with an early onset ≤ three years of age. PATIENTS AND METHODS: 24 consecutive patients (13 females) with acquired comitant non-accommodative esotropia underwent strabismus surgery. Outcome measures included amount of deviation and level of binocularity at last follow-up. RESULTS: An acute onset of strabismus was observed in 83 % of patients. Accompanying features such as diplopia, covering one eye or stumbling were observed in 40 % of the children. Cycloplegic retinoscopy revealed a mild to moderate hypermetropia in all children (mean hypermetropia + 2.2 diopters). 90.5 % of children were aligned within 8 PD of orthotropia. 81 % regained normal stereovision (Lang I/II). CONCLUSIONS: All children exhibited the typical features of acute acquired comitant esotropia (AACE) type II (Burian-Franceschetti). Collective characteristics of this form of strabismus are a comitant and relatively large deviation, mild hypermetropia, a potential of normal binocular cooperation and absence of an accommodative component and neurological pathology. Time and suddenness of strabismus onset may be less helpful in defining this entity.


Asunto(s)
Esotropía/diagnóstico , Esotropía/cirugía , Hiperopía/diagnóstico , Hiperopía/cirugía , Adulto , Diagnóstico Precoz , Femenino , Humanos , Hiperopía/etiología , Masculino , Resultado del Tratamiento
5.
Ophthalmologe ; 107(8): 708-12, 2010 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-20533050

RESUMEN

This article reviews the spectrum of possible motility disorders and ocular misalignment in patients with Möbius sequence. The various options for strabismus surgery are discussed and a stepwise algorithm is presented.


Asunto(s)
Enfermedades del Nervio Abducens/diagnóstico , Enfermedades del Nervio Abducens/cirugía , Síndrome de Mobius/diagnóstico , Síndrome de Mobius/cirugía , Músculos Oculomotores/cirugía , Estrabismo/diagnóstico , Estrabismo/cirugía , Algoritmos , Humanos
7.
Eye (Lond) ; 24(2): 222-5, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19461662

RESUMEN

PURPOSE: Joubert syndrome (JS) is an autosomal-recessive inherited complex malformation of the midbrain-hindbrain. It has been associated with ocular and oculomotor abnormalities. The aim of our study was to extend the ophthalmic knowledge in JS and to add new findings. METHODS: In a retrospective study, 10 consecutive patients, who met the revised diagnostic criteria of JS were included. Mutation analysis was carried out in all the cases. Each patient underwent a comprehensive neuro-ophthalmological examination. RESULTS: Bilateral drusen of the optic disc were found in two patients. Four patients showed bilateral morphological and functional signs of retinal dystrophy (CEP290 mutation in two cases and AHI1 mutation in one case). In nine patients performance during smooth pursuit, saccades, and vestibulo-ocular reflex (VOR) cancellation was poor. CONCLUSIONS: To the best of our knowledge, the association of optic disc drusen with JS has not yet been described. In support of the earlier findings, decreased smooth pursuit and VOR cancellation, as well as partial-to-complete oculomotor apraxia seem to be the key oculomotor features of JS. Genotype-phenotype correlations showed the predictive value of CEP290 and AHI1 mutations for retinal involvement.


Asunto(s)
Retina/patología , Anomalías Múltiples , Adolescente , Adulto , Enfermedades Cerebelosas/genética , Enfermedades Cerebelosas/fisiopatología , Cerebelo/anomalías , Niño , Análisis Mutacional de ADN , Anomalías del Ojo/genética , Anomalías del Ojo/fisiopatología , Femenino , Genotipo , Humanos , Enfermedades Renales Quísticas/genética , Enfermedades Renales Quísticas/fisiopatología , Masculino , Trastornos de la Motilidad Ocular/fisiopatología , Drusas del Disco Óptico/patología , Retina/anomalías , Retina/fisiopatología , Epitelio Pigmentado de la Retina/patología , Estudios Retrospectivos , Movimientos Sacádicos/fisiología , Agudeza Visual/fisiología , Adulto Joven
8.
Eye (Lond) ; 23(7): 1535-41, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18927597

RESUMEN

PURPOSE: The characteristic findings in accidental head injury consist of linear skull fracture, epidural haematoma, localized subdural haematoma, or cortical contusion because of a linear or translational impact force. Retinal haemorrhages have been found, although uncommon, in accidental head trauma. METHODS: We performed a retrospective study of 24 consecutive cases of children with severe head injuries caused by falls. Inclusion criteria were skull fractures and/or intracranial haemorrhages documented by computerized tomography. All patients underwent a careful ophthalmic examination including dilated indirect fundoscopy within the first 48 h following admission. RESULTS: No retinal haemorrhages could be found in patients whose accidents were plausible and physical and imaging findings were compatible with reported histories. Excessive bilateral retinal haemorrhages were found in only three children with the typical signs of shaken baby syndrome. In eight children, trauma had led to orbital roof fractures. CONCLUSIONS: Retinal haemorrhages were not found in any of the patients with accidental trauma despite the severity of their head injuries. Hence, we add more evidence that there are strong differences between the ocular involvement in accidental translational trauma and those in victims of non-accidental trauma. Fall-related injuries carry a very low risk of retinal haemorrhages.


Asunto(s)
Accidentes por Caídas , Traumatismos Craneocerebrales/complicaciones , Hemorragia Retiniana/etiología , Síndrome del Bebé Sacudido/complicaciones , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Hemorragia Retiniana/epidemiología , Estudios Retrospectivos
9.
Br J Ophthalmol ; 92(11): 1492-7, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18703554

RESUMEN

BACKGROUND/AIMS: Age-related macular degeneration (AMD) is among the leading causes of severe visual loss in individuals over 60 years old. Retinal changes associated with AMD were previously studied by time-domain optical coherence tomography (OCT). Recently, Fourier-domain OCT (FD-OCT) has been introduced. FD-OCT provides increased scan resolution and scanning speed, and generates three-dimensional (3D) OCT images. The purpose of this study was to demonstrate features of AMD assessed with high-density scanning 3D-FD-OCT (Topcon 3D-OCT1000). METHODS: The study was designed as a prospective, observational case series. Five patients with typical morphological changes due to AMD were chosen based on funduscopic findings. Eyes with non-exudative- and exudative AMD were included. 3D-FD-OCT images were obtained, and typical morphological changes associated with AMD were presented. RESULTS: FD-OCT provided detailed 3D-images of retinal structure. In addition, FD-OCT showed improved retinal coverage and image quality. FD-OCT B-scan imaging identified typical retinal changes associated with AMD. In addition, FD-OCT imaging revealed information about the extent and the 3D shape of retinal lesions. CONCLUSION: 3D-FD-OCT imaging is useful for diagnosing and following patients with AMD. In addition, 3D-FD-OCT provided information about the extent and 3D shape of retinal pathologies and showed improved retinal coverage.


Asunto(s)
Imagenología Tridimensional/métodos , Mácula Lútea/patología , Degeneración Macular/patología , Disco Óptico/patología , Células Fotorreceptoras de Vertebrados/patología , Tomografía de Coherencia Óptica/métodos , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Angiografía con Fluoresceína/métodos , Análisis de Fourier , Humanos , Estudios Prospectivos
10.
Ann Oncol ; 18(10): 1641-5, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17660493

RESUMEN

BACKGROUND: The present study aimed to assess predictors of distress after 'prophylactic mastectomy (PM) and salpingo-ovariectomy (PSO), in order to enable the early identification of patients who could benefit from psychological support. PATIENTS AND METHODS: General distress and cancer-related distress were assessed in 82 women at increased risk of hereditary breast and/or ovarian cancer undergoing PM and/or PSO, before and 6 and 12 months after prophylactic surgery. Neurotic lability and coping were assessed before surgery. RESULTS: Cancer-related distress and general distress at both follow-up moments were best explained by the level of cancer-related and general distress at baseline. Being a mutation carrier was predictive of increased cancer-related distress at 6-month follow-up (but not at 12 months), and of lower general distress 12 months after prophylactic surgery. Also, coping by having comforting thoughts was predictive of less cancer-related distress at 6-month follow-up. CONCLUSIONS: Genetically predisposed women who are at risk of post-surgical distress can be identified using one or more of the predictors found in this study. Exploration of and/or attention to cancer-related distress and coping style before prophylactic surgery may help physicians and psychosocial workers to identify women who might benefit from additional post-surgical support.


Asunto(s)
Neoplasias de la Mama/prevención & control , Trompas Uterinas/cirugía , Mastectomía/psicología , Neoplasias Ováricas/prevención & control , Ovariectomía/psicología , Estrés Psicológico/etiología , Adaptación Psicológica , Adulto , Neoplasias de la Mama/genética , Neoplasias de la Mama/psicología , Femenino , Predisposición Genética a la Enfermedad/psicología , Heterocigoto , Humanos , Persona de Mediana Edad , Mutación , Neoplasias Ováricas/genética , Neoplasias Ováricas/psicología , Estudios Prospectivos
12.
Eye (Lond) ; 20(6): 697-702, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15933745

RESUMEN

OBJECTIVE: To investigate whether there is an association between the magnitude of retinal haemodynamic abnormalities in patients with age-related macular degeneration (AMD) and the degree of severity of the AMD. METHODS: A retinal laser Doppler system (Canon CLBF 100) was used to measure retinal arterial haemodynamic parameters in 25 eyes of 25 patients with AMD and nine eyes of nine age-matched control subjects. Severity of AMD was classified into Mild (n=11), Moderate (n=7), or Severe (n=7). The pulsatility ratio (PR), the pulsatility index (PI), and the resistivity index (RI) were determined. RESULTS: PR, PI, and RI in the patients with AMD were each significantly higher than in the control group, and increased monotonically with increasing severity of AMD. However, there were no differences in mean blood velocity, arterial diameter, or blood flow rate among the groups. This suggests that the increased blood flow pulsatility in the retinal arteries of the eyes with AMD is not due to increased distal vascular resistance, but instead is likely due to a loss of compliance in the arterial vasculature leading to the eye. CONCLUSION: Our results suggest that an increasing vascular rigidity in the systemic arterial circulation is directly associated with an increasing severity of AMD.


Asunto(s)
Degeneración Macular/fisiopatología , Arteria Retiniana/fisiopatología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Flujometría por Láser-Doppler , Masculino , Flujo Pulsátil , Flujo Sanguíneo Regional , Índice de Severidad de la Enfermedad , Resistencia Vascular
13.
Breast ; 13(4): 329-33, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15325669

RESUMEN

Reports about neuroendocrine (NE) differentiation in breast carcinomas and its possible relation with prognosis are scarce. Furthermore the results of some studies have not been subjected to multivariate survival analysis and the follow-up periods were relatively short. Therefore, in the present long-term follow-up study, the prognostic influence of immunohistochemically defined NE cells, present in the tumours of 40 out of 317 (12.6%) curatively operated breast cancer patients, was studied. The mean follow-up period was 104 months. NE differentiation (NED) was determined by the immunohistochemical detection of chromogranin A and/or synaptophysin. This is concordant with other studies focussing on NED in breast cancer. In contrast to the literature in our series only in 9 out of 40 cases (23%) we were able to detect coexpression of chromogranin A and synaptophysin. This might be due to the characteristics of the antibodies we used. Although most tumours in our series were of the usual type, some tumours with NED were of a special type. Neither univariately, nor taking account of various known prognostic factors, does focal NED appear to carry a special prognostic significance. This finding is in line with results of previous studies.


Asunto(s)
Neoplasias de la Mama/patología , Cromograninas/biosíntesis , Sinaptofisina/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Diferenciación Celular , Cromogranina A , Cromograninas/análisis , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Análisis Multivariante , Sistemas Neurosecretores/fisiología , Pronóstico , Análisis de Supervivencia , Sinaptofisina/análisis
14.
Theor Appl Genet ; 106(7): 1293-9, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12748781

RESUMEN

The recessive mutation of the def gene of pea (Pisum sativum L.) leads to the loss of the hilum, the abscission zone between the seed and the pod. Thereby, it reduces the free dispersal of the seeds through pod shattering. As a prerequisite for a gene isolation via a map-based cloning approach, bulked segregant analysis followed by single plant analyses of over 200 homozygous individuals of a population of 476 F2 plants derived from a cross between 'DGV' (def wild-type) and 'PF' (def mutant), were used to detect markers closely linked to the def locus. The AFLP technique in combination with silver staining was used to maximize numbers of reproducible marker loci. Fifteen AFLP loci showed a genetic distance less than 5 and two of them less than 1 centiMorgans (cM) to the gene of interest. AFLPs were converted into sequence tagged sites (STSs) and into a newly refined AFLP-based single locus marker named the 'sequence specified AFLP' (ssAFLP).


Asunto(s)
Ligamiento Genético , Marcadores Genéticos , Pisum sativum/genética , Proteínas de Plantas/genética , Polimorfismo Genético , Lugares Marcados de Secuencia , Secuencia de Bases , Cartilla de ADN
15.
Proc Natl Acad Sci U S A ; 98(26): 14819-24, 2001 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-11752429

RESUMEN

The amino acid sequence rules that specify beta-sheet structure in proteins remain obscure. A subclass of beta-sheet proteins, parallel beta-helices, represent a processive folding of the chain into an elongated topologically simpler fold than globular beta-sheets. In this paper, we present a computational approach that predicts the right-handed parallel beta-helix supersecondary structural motif in primary amino acid sequences by using beta-strand interactions learned from non-beta-helix structures. A program called BETAWRAP (http://theory.lcs.mit.edu/betawrap) implements this method and recognizes each of the seven known parallel beta-helix families, when trained on the known parallel beta-helices from outside that family. BETAWRAP identifies 2,448 sequences among 595,890 screened from the National Center for Biotechnology Information (NCBI; http://www.ncbi.nlm.nih.gov/) nonredundant protein database as likely parallel beta-helices. It identifies surprisingly many bacterial and fungal protein sequences that play a role in human infectious disease; these include toxins, virulence factors, adhesins, and surface proteins of Chlamydia, Helicobacteria, Bordetella, Leishmania, Borrelia, Rickettsia, Neisseria, and Bacillus anthracis. Also unexpected was the rarity of the parallel beta-helix fold and its predicted sequences among higher eukaryotes. The computational method introduced here can be called a three-dimensional dynamic profile method because it generates interstrand pairwise correlations from a processive sequence wrap. Such methods may be applicable to recognizing other beta structures for which strand topology and profiles of residue accessibility are well conserved.


Asunto(s)
Bacterias/química , Proteínas Bacterianas/química , Bases de Datos de Proteínas , Cristalografía por Rayos X , Estructura Secundaria de Proteína
16.
Mutat Res ; 493(1-2): 87-93, 2001 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-11516718

RESUMEN

The three protocols of the comet assay A/N, A/A and N/N were for the first time applied to the plant species Arabidopsis thaliana. The purpose of the experiments was to establish conditions for genotoxic exposure causing DNA damage in Arabidopsis nuclei. This is required for comprehensive gene expression profiling with the intention to screen for genes involved in response of Arabidopsis cells to genotoxic stress. Five chemicals belonging to different classes of mutagens (the monofunctional alkylating agents N-methyl-N-nitrosourea and methyl methanesulfonate, the polyfunctional alkylating agent mitomycin C, the radiomimetic bleomycin and the herbicide maleic hydrazide) were tested. Except for maleic hydrazide, dose-dependent increases in DNA damage were found using the A/N comet assay protocol. While a rapid repair of bleomycin-mediated SSBs and DSBs was found, no significant reduction of DNA migration was observed up to 48h after treatment with the monofunctional alkylating agents.


Asunto(s)
Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Daño del ADN , Reparación del ADN , Mutágenos/toxicidad , Alquilantes/toxicidad , Arabidopsis/metabolismo , Bleomicina/toxicidad , Ensayo Cometa , Herbicidas/toxicidad , Hidrazida Maleica/toxicidad , Metilmetanosulfonato/toxicidad , Metilnitrosourea/toxicidad , Mitomicina/toxicidad , Mutágenos/clasificación , Fármacos Sensibilizantes a Radiaciones/toxicidad
17.
Mutat Res ; 493(1-2): 95-100, 2001 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-11516719

RESUMEN

We have established the comet assay for detection of DNA damage in barley. Immediately after treatment with the monofunctional alkylating agent MNU, a dose-dependent increase of DNA damage (mainly DNA breaks) was detected by the alkaline denaturation/neutral gel electrophoresis (A/N) variant of the comet assay in nuclei isolated from root tip meristems and from young leaves. A reduction of damage was observed within meristematic nuclei but not in differentiated leaf nuclei 48h after treatment. Adaptive pretreatment with a nontoxic dose of cadmium chloride prior to challenge treatment with MNU reduced the frequency of chromatid type aberrations, micronuclei and aneuploid cells as well as the amount of DNA in comet tails of meristematic nuclei.


Asunto(s)
Daño del ADN , Hordeum/efectos de los fármacos , Hordeum/genética , Metilnitrosourea/toxicidad , Alquilantes/toxicidad , Aneuploidia , Cloruro de Cadmio/farmacología , Aberraciones Cromosómicas , Ensayo Cometa , Micronúcleos con Defecto Cromosómico/efectos de los fármacos
18.
J Dermatol Sci ; 26(1): 36-45, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11323219

RESUMEN

The histological diagnosis of initial mycosis fungoides (MF) and the molecular mechanisms that are responsible for its progression and transformation to the more highly malignant variants of MF remain largely unknown. Because of the rare occurrence of these tumours, the need for snap frozen skin biopsy specimens and the difficulty to obtain suitable material for karyotypic and genotypic analysis, specific cytogenetic and molecular lesions have not yet been identified. In particular the role of known oncogenes and tumour suppressor genes, including the p53 gene, in the pathogenesis and clinical progression of MF has not been extensively investigated. The present study was carried out using the polymerase chain reaction (PCR) technique combined with temperature gradient gel electrophoresis (TGGE) to detect mutations of the p53 gene in 58 patients with MF. TGGE analysis was also used in combination with clonality analysis by means of T-cell receptor gamma (TCRG) gene rearrangement studies to distinguish parapsoriasis en plaque and initial MF from patch/plaque stage MF. More than 83% of the diagnoses of initial MF could be confirmed using PCR-TGGE analysis. However, although the sensitive TGGE analysis was used for all exons, p53 gene polymorphisms were found in 4 and p53 gene mutation in only 1 of 58 biopsy specimens. It appears unlikely that p53 gene mutations play a role in either the pathogenesis of parapsoriasis and initial MF or their progression to advanced stages of MF. However, TCRG gene rearrangement studies by means of TCR-TGGE analysis may be useful for distinguishing histologically discordant cases of initial MF.


Asunto(s)
Genes p53 , Micosis Fungoide/genética , Micosis Fungoide/patología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Biopsia , Humanos , Mutación , Polimorfismo Genético
19.
J Clin Oncol ; 19(4): 924-30, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11181654

RESUMEN

PURPOSE: Women with a high breast cancer risk due to a familial predisposition may choose between preventive surgery and regular surveillance. The effectiveness of surveillance in high-risk women and especially BRCA1/2 mutation carriers is unknown. We present first results from a single large family cancer clinic. PATIENTS AND METHODS: Women with breast cancer risk over 15% were examined by physical examination every 6 months and mammography every year. Detection rates and screening parameters were calculated for the total group and separately for different age and genetic risk groups. RESULTS: At least one examination was performed in 1,198 women: 449 moderate and 621 high-risk women and 128 BRCA1/2 mutation carriers. Within a median follow-up of 3 years, 35 breast cancers were detected (four ductal carcinoma-in-situ; 31 invasive tumors); the average detection rate was 9.7 per 1,000. Detection rates (95% confidence interval) for moderate and high-risk women and BRCA1/2 carriers were 3.3 (1.1 to 8.6), 8.4 (5.4 to 13.2), and 33 (17 to 63) per 1,000 person-years, respectively. The ratio of observed cases versus breast cancers expected in an average-risk population of comparable age was 2.7, 7.0 and 23.7 respectively. Overall, node negativity was 65%; 34% of primary tumors were less than 10 mm; sensitivity was 74%. Results with respect to tumor stage and sensitivity were less favorable in BRCA1/2 carriers and in women under the age of 40. CONCLUSION: It is possible to identify young women at high risk for breast cancer. The number of cancers detected was significantly greater than expected in an age-matched average-risk population and related to the risk category. Overall, screening parameters were comparable to population screening data, with less favorable results in the youngest age group (< 40) and BRCA1/2 carriers.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Genes BRCA1 , Heterocigoto , Proteínas de Neoplasias/genética , Factores de Transcripción/genética , Adulto , Factores de Edad , Anciano , Proteína BRCA2 , Femenino , Humanos , Mamografía , Persona de Mediana Edad , Mutación , Riesgo
20.
Mutagenesis ; 15(6): 503-6, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11077002

RESUMEN

The genotoxic effect of the monofunctional alkylating agent N:-methyl-N:-nitrosourea (MNU) on root-tip nuclei of the field bean, Vicia faba, has been tested by comparative application of three protocols of the comet assay. While the alkaline denaturation/alkaline electrophoresis (A/A) procedure proved to be most sensitive at low doses, the alkaline denaturation/neutral electrophoresis (A/N) procedure yielded an optimal dose-response curve within a wider dose range. With the neutral electrophoresis without alkaline denaturation (N/N) procedure only minimal response was found. MNU-mediated single-strand breaks occurred in nuclei of all interphase stages. Detection of tandemly repeated FOK:I elements on comets by fluorescence in situ hybridization showed an average involvement of these heterochromatin-specific sequences in MNU-mediated single-strand breaks. This, together with previous results, suggests that the pronounced clustering of chromosomal aberrations in heterochromatic regions after treatment with S phase-dependent mutagens is mainly due to an error-prone interference of recombinative repair and replication in damaged basic repeats of large tandem repeat arrays.


Asunto(s)
Alquilantes , Núcleo Celular/metabolismo , Cromátides/genética , Daño del ADN/efectos de los fármacos , Interfase/efectos de los fármacos , Metilnitrosourea , Ciclo Celular/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Separación Celular , Aberraciones Cromosómicas , Cromosomas/efectos de los fármacos , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Electroforesis , Citometría de Flujo , Hibridación Fluorescente in Situ , Plantas/efectos de los fármacos
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