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1.
Sci Rep ; 14(1): 21681, 2024 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289469

RESUMEN

Undifferentiated pleomorphic sarcoma (UPS) is the largest subgroup of soft tissue sarcomas. This study determined the value of perfusion-weighted imaging with dynamic-contrast-enhancement (PWI/DCE) morphologic, qualitative, and semiquantitative features for predicting UPS pathology-assessed treatment effect (PATE). This retrospective study included 33 surgically excised extremity UPS patients with pre-surgical MRI. Volumetric tumor segmentation from PWI/DCE was obtained at Baseline (BL), Post-Chemotherapy (PC), and Post-Radiation Therapy (PRT). The surgical specimens' PATE separated cases into Responders (R) (≥ 90%, 16 patients), Partial-Responders (PR) (89 - 31%, 10 patients), and Non-Responders (NR) (≤ 30%, seven patients). Seven semiquantitative kinetic parameters and maps were extracted from time-intensity curves (TICs), and 107 radiomic features were derived. Statistical analyses compared R vs. PR/NR. At PRT, 79% of R displayed a "Capsular" morphology (P = 1.49 × 10-7), and 100% demonstrated a TIC-type II (P = 8.32 × 10-7). 80% of PR showed "Unipolar" morphology (P = 1.03 × 10-5), and 60% expressed a TIC-type V (P = 0.06). Semiquantitative wash-in rate (WiR) was able to separate R vs. PR/NR (P = 0.0078). The WiR radiomics displayed significant differences in the first_order_10 percentile (P = 0.0178) comparing R vs. PR/NR at PRT. The PWI/DCE TIC-type II curve, low WiR, and "Capsular" enhancement represent PRT patterns typically observed in successfully treated UPS and demonstrate potential for UPS treatment response assessment.


Asunto(s)
Medios de Contraste , Sarcoma , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Adulto , Estudios Retrospectivos , Sarcoma/diagnóstico por imagen , Sarcoma/terapia , Sarcoma/patología , Sarcoma/radioterapia , Resultado del Tratamiento , Imagen por Resonancia Magnética/métodos , Anciano de 80 o más Años , Radiómica
2.
Radiography (Lond) ; 29(2): 327-332, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36706601

RESUMEN

INTRODUCTION: To establish if the CT dataset acquired during the stress element of myocardial perfusion imaging can be fused to the subsequent rest scan to reduce radiation doses from these procedures. METHODS: 86 rest scans were processed and evaluated using a self-designed project specific tool. Recording processing time, the time between the two data sets selected for fusion and assessing radiographic reports to ensure produced images were of diagnostic quality. RESULTS: 70% of fused scans were acquired 6-7 days apart; the mean (SD) processing time was calculated as 2.03 (0.36) minutes. The Pearson's correlation between these two variables was determined to be 0.22, showing a slight positive correlation although not statistically significant. 100% of the images produced were of diagnostic quality. CONCLUSION: Rest scans can be fused to a previously acquired CT, careful consideration should be given when positioning the patient and to the time interval between acquiring the two data sets, departmental guidelines can assist with this. Staff training may also be beneficial to ensure staff can assess if data sets are fusible prior to completing a scan. IMPLICATIONS FOR PRACTICE: This data provides evidence that retrospective fusion can reduce patient radiation doses in myocardial perfusion imaging without compromising diagnostic outcomes. Dose optimisation is an essential part of the ionising radiation (medical exposure) regulations therefore retrospective fusion should be considered in practice to ensure departmental compliance, although it is noteworthy this study is solely based in a single centred one camera department.


Asunto(s)
Imagen de Perfusión Miocárdica , Humanos , Imagen de Perfusión Miocárdica/métodos , Estudios Retrospectivos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X/métodos , Dosis de Radiación
3.
J Plast Reconstr Aesthet Surg ; 74(8): 1919-1930, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33436338

RESUMEN

INTRODUCTION: A detailed three-dimensional (3D) evaluation of microvasculature is evolving to be a powerful tool, providing mechanistic understanding of angiomodulating strategies. The aim of this study was to evaluate the microvascular architecture of nerve allografts after combined stem cell delivery and surgical angiogenesis in a rat sciatic nerve defect model. MATERIALS AND METHODS: In 25 Lewis rats, sciatic nerve gaps were repaired with (i) autografts, (ii) allografts, (iii) allografts wrapped in a pedicled superficial inferior epigastric artery fascia (SIEF) flap to provide surgical angiogenesis, combined with (iv) undifferentiated mesenchymal stem cells (MSC) and (v) MSCs differentiated into Schwann cell-like cells. At two weeks, vascular volume was measured using microcomputed tomography, and percentage and volume of vessels at different diameters were evaluated and compared with controls. RESULTS: The vascular volume was significantly greatest in allografts treated with undifferentiated MSCs and surgical angiogenesis combined as compared to all experimental groups (P<0.01 as compared to autografts, P<0.0001 to allografts, and P<0.05 to SIEF and SIEF combined with differentiated MSCs, respectively). Volume and diameters of vessel segments in nerve allografts were enhanced by surgical angiogenesis. These distributions were further improved when surgical angiogenesis was combined with stem cells, with greatest increase found when combined with undifferentiated MSCs. CONCLUSIONS: The interaction between vascularity and stem cells remains complex, however, this study provides some insight into its synergistic mechanisms. The combination of surgical angiogenesis with undifferentiated MSCs specifically, results in the greatest increase in revascularization, size of vessels, and stimulation of vessels to reach the middle longitudinal third of the nerve allograft.


Asunto(s)
Neovascularización Fisiológica , Nervio Ciático/cirugía , Trasplante de Células Madre , Aloinjertos , Animales , Autoinjertos , Diferenciación Celular , Masculino , Microcirculación , Modelos Animales , Regeneración Nerviosa , Transferencia de Nervios , Ratas , Ratas Endogámicas Lew , Colgajos Quirúrgicos/irrigación sanguínea , Microtomografía por Rayos X
4.
Gene ; 618: 24-27, 2017 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-28322993

RESUMEN

The ability to improve or restore blood flow and promote healing in ischemic tissue has many potential clinical applications. Augmentation by direct delivery of growth factors may further enhance results, but requires a method for sustained delivery. In this study, we have tested the ability of adeno-associated virus 9 (AAV9) delivered within the lumen of a porcine artery to transfect the vessel and produce a desired product. The marker chosen was green fluorescent protein (GFP) (Ke et al., 2011). In 4 farm pigs the cranial tibial artery was surgically exposed. The vessel was temporarily clamped proximally, and divided distally. A cannula was placed intraluminally, and the arterial segment was injected with 1×10E13 particles of AAV9.CB7.CI.GFP·WPRE.rBG. At 14days the transfected cranial tibial artery as well as the liver, spleen and kidneys were harvested. ELISA and reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) were used to analyze the artery for GFP production. Significant GFP expression was seen in all transfected cranial tibial vessels, as determined by both GFP protein production (ELISA) and mRNA (RT-qPCR). No GFP was identified in liver, spleen or kidney, nor in the no-GFP control animal artery. Adeno-associated virus 9 is an appropriate vector for gene therapy experiments in the porcine artery model. This vector, and the intraluminal deliver method described result in robust gene expression at 2weeks without evident systemic spill of the virus. The ability to limit delivery of the gene to an isolated segment of vessel is desirable for future research applications.


Asunto(s)
Dependovirus/genética , Terapia Genética/métodos , Arterias Tibiales , Animales , ADN Recombinante/administración & dosificación , ADN Recombinante/genética , Técnicas de Transferencia de Gen , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Inyecciones Intraarteriales , Porcinos
5.
Bone Joint J ; 99-B(1): 134-138, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28053269

RESUMEN

AIMS: Free vascularised fibular grafting has been used for the treatment of large bony defects for more than 40 years. However, there is little information about the risk factors for failure and whether newer locking techniques of fixation improve the rates of union. The purpose of this study was to compare the rates of union of free fibular grafts fixed with locking and traditional techniques, and to quantify the risk factors for nonunion and failure. PATIENTS AND METHODS: A retrospective review involved 134 consecutive procedures over a period of 20 years. Of these, 25 were excluded leaving 109 patients in the study. There were 66 men and 43 women, with a mean age of 33 years (5 to 78). Most (62) were performed for oncological indications, and the most common site (52) was the lower limb. Rate of union was estimated using the Kaplan-Meier method and risk factors for nonunion were assessed using Cox regression. All patients were followed up for at least one year. RESULTS: The rate of union was 82% at two years and 97% at five years. Union was achieved after the initial procedure in 76 patients (70%) at a mean of ten months (3 to 19), and overall union was achieved in 99 patients (91%). No surgical factor, including the use of locked fixation or supplementary corticocancellous bone grafts increased the rate of union. A history of smoking was significantly associated with a risk of nonunion. DISCUSSION: Free vascularised fibular grafting is a successful form of treatment for large bony defects. These results suggest that the use of modern techniques of fixation does not affect the risk of nonunion when compared with traditional forms of fixation, and smoking increases the risk of nonunion following this procedure. Cite this article: Bone Joint J 2017;99-B:134-8.


Asunto(s)
Neoplasias Óseas/cirugía , Trasplante Óseo/métodos , Colgajos Tisulares Libres/trasplante , Adolescente , Adulto , Anciano , Trasplante Óseo/efectos adversos , Niño , Preescolar , Femenino , Peroné/trasplante , Colgajos Tisulares Libres/efectos adversos , Supervivencia de Injerto/fisiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Reoperación , Factores de Riesgo , Recolección de Tejidos y Órganos/métodos , Sitio Donante de Trasplante , Resultado del Tratamiento , Cicatrización de Heridas/fisiología , Adulto Joven
6.
Childs Nerv Syst ; 31(5): 693-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25735848

RESUMEN

OBJECTIVES: This study aimed to investigate the inter-rater reliability and construct validity of the Scale for the Assessment and Rating of Ataxia (SARA) and Brief Ataxia Rating Scale (BARS) in children with posterior fossa tumours. These scales have been developed for adults with genetic ataxias, and the performance of these scales in children with brain tumours has not previously been described. METHODS: The participants, who had undergone surgical resection for a posterior fossa tumour (inclusion criteria age 4-18 years), were recruited from the neuro-oncology service at a tertiary children's hospital. Children were assessed using the SARA, BARS and Paediatric Evaluation of Disability Index (PEDI) mobility domain, a measure of function. Children were independently rated by two therapists to determine the inter-rater reliability of the SARA and BARS. The construct validity was determined by assessing the correlation between the two scales with the PEDI. RESULTS: Forty-four children were recruited. Inter-rater reliability was good for both scales, demonstrating the strong correlations (SARA, r = 0.94; BARS, r = 0.91) and the good consistency (93 % of SARA and 90 % of BARS paired scores differing by less than 2 points) between two raters. Both ataxia scales demonstrated a strong negative correlation with the mobility domain of the PEDI (SARA, r = -0.77; BARS, r = -0.76), indicating that more severe ataxia was associated with worse mobility. The mean time for completion of the SARA was 4.5 and 2.7 min for the BARS. CONCLUSIONS: The SARA and BARS are reliable and valid measures and appear to be of equal value in determining the severity of ataxia in children with posterior fossa tumours.


Asunto(s)
Ataxia/diagnóstico , Neoplasias Encefálicas/complicaciones , Fosa Craneal Posterior/patología , Evaluación de la Discapacidad , Examen Neurológico , Neoplasias de la Base del Cráneo/complicaciones , Adolescente , Ataxia/etiología , Neoplasias Encefálicas/patología , Niño , Preescolar , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Neoplasias de la Base del Cráneo/patología
7.
J Plast Reconstr Aesthet Surg ; 67(1): 1-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24090720

RESUMEN

BACKGROUND: Autologous fat grafting to the velopharynx has been described for treatment of velopharyngeal insufficiency for over a decade. The aim of this review was to evaluate outcomes of autologous fat grafting for velopharyngeal insufficiency. METHODS: A computerized search was performed across multiple databases. Studies involving patients undergoing autologous fat grafting for velopharyngeal insufficiency treatment that reported at least one pre- and post-intervention outcome measure were included. RESULTS: A systematic search revealed eleven studies that satisfied inclusion criteria. All were case series or noncomparative observational studies. Three reported on isolated posterior pharyngeal wall augmentation, while eight involved augmentation of the pharyngeal arches, velum and/or posterior pharyngeal wall. In general, selected patients had plateaued with regards to speech therapy and had small-to-moderate velopharyngeal closure defects. Although most patients had a cleft palate diagnosis, the proportion that had previous velopharyngoplasty, or other related diagnoses was highly variable. In all but one report outcome measures included perceptual speech assessment. Objective measures such as nasalance and fat graft take were inconsistently reported. Overall, results of fat grafting for velopharyngeal insufficiency were variable and depended on assessment modality. One case of obstructive sleep apnea was reported. CONCLUSIONS: Despite potential benefits of autologous fat grafting for velopharyngeal insufficiency, questions remain as to patient selection, safety, and optimal graft volume and injection sites. This review underscores the need for standardized assessment methods and prospective comparative studies or randomized controlled trials to compare fat grafting with established velopharyngoplasty techniques to better define indications for its use.


Asunto(s)
Tejido Adiposo/trasplante , Insuficiencia Velofaríngea/cirugía , Fisura del Paladar/cirugía , Humanos , Trastornos del Habla/cirugía , Resultado del Tratamiento
8.
J Biomed Nanotechnol ; 8(4): 703-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22852480

RESUMEN

PM02734 is a chemically synthesized depsipeptide derived from the marine kahalalides family with a broad spectrum of activity against solid tumors in vitro and in vivo, but presenting low bioavailability. In this work, solid lipid nanoparticles made of Precirol ATO 5 have been developed using a hot homogenization method followed by high shear homogenization and ultrasonication. These solid lipid nanoparticles show suitable size (around 150 nm) and encapsulation efficiency (nearly 70%) for the oral administration of the compound PM02734. A physical-chemical stability study was performed after 6 months of storage at different thermical conditions, concluding that solid lipid nanoparticles stored at 4 degrees C were more stable than solid lipid nanoparticles stored at 25 degrees C. The pharmacokinetic profile of drug-loaded solid lipid nanoparticles was also evaluated in Beagle dogs and compared with that of a cyclodextrin-based delivery system by means of AUC, C(max) and T(max) parameter estimation. Solid lipid nanoparticle based formulation provided a sustained release of the drug for a longer period of time than the cyclodextrins.


Asunto(s)
Ciclodextrinas/farmacocinética , Depsipéptidos/farmacocinética , Nanopartículas/química , Animales , Disponibilidad Biológica , Ciclodextrinas/administración & dosificación , Ciclodextrinas/química , Depsipéptidos/administración & dosificación , Depsipéptidos/química , Perros , Portadores de Fármacos/farmacocinética , Sistemas de Liberación de Medicamentos , Estabilidad de Medicamentos , Lípidos/administración & dosificación , Lípidos/química , Lípidos/farmacocinética , Conformación Molecular , Nanopartículas/administración & dosificación , Tamaño de la Partícula
9.
J Invertebr Pathol ; 107(2): 132-8, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21457716

RESUMEN

Several strains of Bacillus thuringiensis were previously isolated from soil in Antarctica and appeared to have physiological adaptations to this cold, nutrient-poor environment. In spite of this they could produce abnormally large, parasporal crystals under laboratory conditions. Here, they have been further characterised for toxin genes and invertebrate pathogenicity. All of the strains were positive in PCR assays for the cry1Aa and cry2 genes. This was confirmed by sequence analysis and the parasporal crystals of all strains contained polypeptides of about 130kDa. This potential for lepidopteran toxicity was borne out in bioassays of purified δ-endotoxins against larvae of Pieris brassicae: the LD(50) values of B2408 (288µg) were comparable to that of the reference strain, HD-12 (201µg). There was no activity against the nematode Caenorhabditis elegans in spite of the fact that all strains appeared to possess the cry6 gene. PCR screening for genes encoding other nematode-toxic classes of toxins (Cry5, 4 and 21) was negative. B. thuringiensis has never previously been shown to be toxic to Collembola (springtails) but the purified δ-endotoxins of one of the Antarctic strains showed some activity against Folsomia candida and Seira domestica (224µg and 238µg, respectively). It seems unlikely that the level of toxicity demonstrated against springtails would support a pathogenic life-style in nature. All of the strains were positive for genes encoding Bacillus cereus-type enterotoxins. In the absence of higher insects and mammals the ecological value of retaining the toxic capability demonstrated here is uncertain.


Asunto(s)
Bacillus thuringiensis/patogenicidad , Toxinas Bacterianas/metabolismo , Lepidópteros/microbiología , Control Biológico de Vectores/métodos , Adaptación Fisiológica , Animales , Regiones Antárticas , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/toxicidad , Toxinas Bacterianas/toxicidad , Brassica/microbiología , Caenorhabditis elegans/efectos de los fármacos , Endotoxinas/genética , Endotoxinas/metabolismo , Endotoxinas/toxicidad , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidad , Insecticidas/toxicidad , Dosificación Letal Mediana , Hojas de la Planta/microbiología
10.
J Hand Surg Eur Vol ; 35(7): 569-74, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20237188

RESUMEN

The success of vascularized bone grafts from the medial femoral condyle in various clinical applications has sparked renewed interest in the microvascular anatomy of this region. This study describes the arterial supply of the distal medial femoral condyle and its implications in harvesting vascularized bone grafts. The location, branching pattern, internal diameter, and distribution of perforators of the descending genicular artery and superior medial genicular artery in 19 fresh cadaveric lower limbs were recorded. The descending genicular artery was present in 89% and the superior medial genicular artery was present in 100% of specimens with average distances proximal to the articular surface of 13.7 cm and 5.2 cm, respectively. The average number of perforating vessels was greatest in the posterior distal quadrant of the condyle. The blood supply of the medial femoral condyle is plentiful and consistent making it a useful source for free vascularized bone grafts.


Asunto(s)
Trasplante Óseo , Fémur/irrigación sanguínea , Fémur/trasplante , Recolección de Tejidos y Órganos , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Disección , Epífisis/irrigación sanguínea , Epífisis/trasplante , Humanos , Persona de Mediana Edad , Periostio/irrigación sanguínea , Periostio/trasplante , Flujo Sanguíneo Regional , Reproducibilidad de los Resultados
11.
Neurogastroenterol Motil ; 22(1): 70-8, e29, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19650770

RESUMEN

We aimed to evaluate the changes of nerve morphology and distribution of neurotransmitters and neuropeptides in the rectum of Shigella flexneri-infected patients and in the duodenum of Vibrio cholerae O1-infected patients. Nerve morphology was observed by transmission electron microscopy. Immunoreactivity of nerve growth factor (NGF), neurotransmitters and neuropeptides in tissues were studied by immunohistochemistry. Ultrastructural analysis of intestinal biopsy revealed persisting axons degeneration throughout the study period in all patients. Regeneration was already evident at the acute stage with marked increase at late convalescence. Both acute shigellosis and cholera were accompanied by increased expression of NGF and histamine and decreased expression of serotonin that was restored at convalescence. Immunoreactivity of vasoactive intestinal peptide (VIP) was increased during acute cholera, whereas in shigellosis VIP- and substance P-immunoreactive nerves appeared at early convalescence. Both shigellosis and cholera induced long-lasting degeneration of enteric neuronal axons, despite the presence of ongoing proliferation and regeneration processes. Neurotransmitters and neuropeptides may play differential roles in invasive and watery diarrhoea.


Asunto(s)
Diarrea/inmunología , Diarrea/patología , Sistema Nervioso Entérico , Neuronas , Recto , Adolescente , Adulto , Biopsia , Cólera/inmunología , Cólera/patología , Diarrea/microbiología , Disentería Bacilar/inmunología , Disentería Bacilar/patología , Sistema Nervioso Entérico/citología , Sistema Nervioso Entérico/inmunología , Histamina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factor de Crecimiento Nervioso/metabolismo , Neuronas/metabolismo , Neuronas/ultraestructura , Recto/citología , Recto/inervación , Recto/metabolismo , Serotonina/metabolismo , Sustancia P/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Péptido Intestinal Vasoactivo/metabolismo , Vibrio cholerae O1/metabolismo , Vibrio cholerae O1/patogenicidad , Adulto Joven
12.
Int J Syst Evol Microbiol ; 59(Pt 8): 2114-21, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19567583

RESUMEN

Minimal standards for describing new taxa within the aerobic endospore-forming bacteria are proposed, following Recommendation 30b of the Bacteriological Code (1990 Revision). These minimal standards are recommended as guidelines to assist authors in the preparation of descriptions for novel taxa. They encourage broad polyphasic characterization and the construction of descriptions that are practically useful in routine diagnostic laboratories. The proposals have been endorsed by the Subcommittee on the Taxonomy of the Genus Bacillus and Related Organisms of the International Committee on Systematics of Prokaryotes.


Asunto(s)
Bacterias Formadoras de Endosporas/clasificación , Terminología como Asunto
14.
Anaesthesia ; 63(12): 1365-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18717658

RESUMEN

SUMMARY: We present the case of a 65-year-old male with severe coronary artery disease and a single colorectal liver metastasis. An elective intra-aortic balloon pump (IABP) was inserted following induction of anaesthesia to reduce left ventricular workload during his liver resection. After an uneventful recovery he was discharged on day 5. We review the literature on the elective use of these devices in cardiac surgery in which it is becoming routine practice in high risk patients. However in non-cardiac surgery there have been only 15 published cases all in very high risk patients, with favourable outcomes. To our knowledge this is the first published case of the use of elective IABP during liver surgery.


Asunto(s)
Adenocarcinoma/cirugía , Enfermedad Coronaria/terapia , Contrapulsador Intraaórtico , Cuidados Intraoperatorios/métodos , Neoplasias Hepáticas/cirugía , Adenocarcinoma/complicaciones , Adenocarcinoma/secundario , Anciano , Enfermedad Coronaria/complicaciones , Hepatectomía/métodos , Humanos , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/secundario , Masculino , Neoplasias del Recto/complicaciones , Neoplasias del Recto/cirugía
15.
Clin Exp Immunol ; 147(3): 472-82, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17302896

RESUMEN

An important limitation in T cell studies of human autoimmune (type 1) diabetes is lack of direct access to cells infiltrating the pancreas. We hypothesized that cells recently released from the pancreas into the blood might express a characteristic combination of markers of activation. We therefore examined the recently activated circulating T cell population [CD3+, human leucocyte antigen D-related (HLA-DR+)] using cytokine production and 10 additional subset markers [CD69, CD25, CD122, CD30, CD44v6, CD57, CD71, CCR3 (CD193), CCR5 (CD195) or CXCR3 (CD183)], comparing newly diagnosed adult (ND) (age 18-40 years) patients (n=19) to patients with diabetes for >10 years [long-standing (LS), n=19] and HLA-matched controls (C, n=16). CD3+ DR+ cells were enriched by two-step immunomagnetic separation. No differences in basal or stimulated production of interleukin (IL)-4, IL-10, IL-13 or interferon (IFN)-gamma by CD3+ DR+ enriched cells were observed between the different groups of subjects. However, among the CD3+ DR+ population, significant expansions appeared to be present in the very small CD30+, CD69+ and CD122+ subpopulations. A confirmatory study was then performed using new subjects (ND=26, LS=15), three-colour flow cytometry, unseparated cells and three additional subset markers (CD38, CD134, CD4/CD25). This confirmed the expansion of the CD3+ DR+ CD30+ subpopulation in ND subjects. We conclude that a relative expansion in the T cell subpopulation with the activated phenotype CD3+ DR+ CD30+ is seen in the peripheral blood of subjects with newly diagnosed type 1 diabetes. This subpopulation represents less than 0 x 7% of circulating T cells and may provide a rich source of disease-specific T cells that can be isolated from blood.


Asunto(s)
Diabetes Mellitus Tipo 1/inmunología , Antígeno Ki-1/sangre , Activación de Linfocitos/inmunología , Subgrupos de Linfocitos T/inmunología , Adolescente , Adulto , Complejo CD3/sangre , Citocinas/biosíntesis , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Citometría de Flujo/métodos , Antígenos HLA-DR/sangre , Prueba de Histocompatibilidad , Humanos , Separación Inmunomagnética , Masculino , Factores de Tiempo
17.
DNA Repair (Amst) ; 5(7): 863-7, 2006 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-16774850

RESUMEN

Short-wave ultra-violet light promotes the formation of DNA dimers between adjacent thymine bases, and if unrepaired these dimers may induce skin cancer. Living cells have a very robust repair system capable of repairing hundreds of lesions every day. Although many of the details of the dimer repair mechanism are known, it is still a mystery how the dimers are recognized. Because the dimers are hidden from repair proteins diffusing in the cell nucleus, it has been surmised that dimer recognition is indirect. In this paper, a new recognition signal is suggested by a theory of the dimer-induced large amplitude, prolonged oscillations in the motion of the two strands in double-stranded DNA molecules. These large amplitude oscillations of the two DNA strands, localized around the dimer will unveil the dimer allowing the repair proteins to bind to the dimer site. The temperature dependence of the recognition rate is correlated with the inter-strand fluctuations and must decrease with decreasing temperature according to the findings in this paper. Moreover the probability for finding a large opening is localized to the dimer neighbourhood and these large openings may play an important role in dimer-repair protein biochemistry.


Asunto(s)
Reparación del ADN , Dímeros de Pirimidina/metabolismo , Dímeros de Pirimidina/efectos de la radiación , ADN/química , ADN/metabolismo , ADN/efectos de la radiación , Daño del ADN , Humanos , Técnicas In Vitro , Modelos Biológicos , Método de Montecarlo , Rayos Ultravioleta/efectos adversos
18.
DNA Repair (Amst) ; 5(1): 111-20, 2006 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-16202662

RESUMEN

p21/WAF1/CIP1/MDA6 is a key cell cycle regulator. Cell cycle regulation is an important part of development, differentiation, DNA repair and apoptosis. Following DNA damage, p53 dependent expression of p21 results in a rapid cell cycle arrest. p21 also appears to be important for the development of melanocytes, promoting their differentiation and melanogenesis. Here, we examine the effect of p21 deficiency on the development of another pigmented tissue, the retinal pigment epithelium. The murine mutation pink-eyed unstable (p(un)) spontaneously reverts to a wild-type allele by homologous recombination. In a retinal pigment epithelium cell this results in pigmentation, which can be observed in the adult eye. The clonal expansion of such cells during development has provided insight into the pattern of retinal pigment epithelium development. In contrast to previous results with Atm, p53 and Gadd45, p(un) reversion events in p21 deficient mice did not show any significant change. These results suggest that p21 does not play any role in maintaining overall genomic stability by regulating homologous recombination frequencies during development. However, the absence of p21 caused a distinct change in the positions of the reversion events within the retinal pigment epithelium. Those events that would normally arrest to produce single cell events continued to proliferate uncovering a cell cycle dysregulation phenotype. It is likely that p21 is involved in controlling the developmental pattern of the retinal pigment. We also found a C57BL/6J specific p21 dependent ocular defect in retinal folding, similar to those reported in the absence of p53.


Asunto(s)
Tipificación del Cuerpo/fisiología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Epitelio Pigmentado Ocular/embriología , Recombinación Genética , Animales , Proliferación Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Daño del ADN/fisiología , Ojo/citología , Ojo/crecimiento & desarrollo , Anomalías del Ojo/genética , Regulación del Desarrollo de la Expresión Génica , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Epitelio Pigmentado Ocular/citología , Epitelio Pigmentado Ocular/crecimiento & desarrollo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
19.
Tissue Eng ; 11(7-8): 1115-21, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16144447

RESUMEN

After lung injury and damage to the alveolar epithelium, the underlying basement membranes become exposed. Proliferation of type II pneumocytes and their differentiation to the type I phenotype have been considered to be the mechanism by which repopulation of the alveolar epithelium occurs. A growing body of evidence has shown that tissues can be repaired by cells acquired via the circulation. For the lung, bone marrow stem cells have been shown in mice to regenerate epithelium as well as give rise to the expected mesodermal derivatives. We hypothesized that extrapulmonary cells, including those from the bone marrow, can contribute to the reepithelialization of human alveoli. To investigate this, we examined samples of peripheral lung from patients who had undergone cross-gender transplantation of lung or bone marrow. Thus, archival blocks of peripheral lung were analyzed from male patients (surgical samples, n = 8) who had received a lung transplant from a female donor and female patients (postmortem samples, n = 3) who had male bone marrow transplants. In both cases, male cells were identified in the female lungs by Y chromosome in situ hybridization. Male cells could be identified in the alveolar epithelium where, in the better preserved, transplanted lungs, it was possible to show that some had differentiated to type II pneumocytes. In addition, Y chromosomes were found to be widespread in cells of mesenchymal lineage, including macrophages and endothelial cells. Concomitant visualization of Y and X chromosomes, using fluorescence immunolabeling, yielded no evidence of cellular fusion, although the poor quality of the autopsy samples studied meant that the possibility could not be excluded. These observations suggest that, as occurs in rodents, the epithelium of the adult human lung has the capacity to renew itself, using cells recruited from extrapulmonary sources, including the bone marrow. This finding could provide new therapeutic opportunities for a range of pulmonary diseases by providing means to repair the lung and a novel route for gene therapy.


Asunto(s)
Células de la Médula Ósea/patología , Enfermedades Pulmonares/patología , Trasplante de Pulmón/patología , Pulmón/citología , Mucosa Olfatoria/citología , Regeneración , Adulto , Diferenciación Celular , Niño , Femenino , Humanos , Técnicas In Vitro , Lactante , Pulmón/fisiopatología , Enfermedades Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Mucosa Olfatoria/fisiopatología
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