Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Appl Radiat Isot ; 194: 110651, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36696750

RESUMEN

The Cavezzo meteorite was recovered on January 4th, 2020, just three days after the fall observed over Northern Italy by the all-sky cameras of the Italian PRISMA fireball network. Two specimens, weighing 3.1 g (F1) and 52.2 g (F2), were collected in the predicted strewn-field and the meteorite has been classified as an L5 anomalous chondrite. The gamma-activity of the F2 sample was measured at the Monte dei Cappuccini underground Research Station (Torino, Italy) with a large-volume HPGe-NaI(Tl) spectrometer. Thanks to the high efficiency, selectivity, and low background of the spectrometer, we were able to detect fifteen cosmogenic radioisotopes. The presence of nuclides with half-lives down to a few days (47Ca, 52Mn, and 48V) undoubtedly confirmed the recent fall of the sample. The very low activity of 44Ti and 60Co was revealed with a particular coincidence between the HPGe and NaI(Tl) detectors. To obtain the detection efficiency, we have simulated the response of the detector with the GEANT4 toolkit, once the spectrometer's dead layer thickness was estimated using standards of known activity. Moreover, the simulation of the Dhajala meteorite (H3/4 chondrite) measurement allowed us to verify that the self-absorption of the sample is correctly taken into account and validate our simulations. In this contribution, we focus on the coincidence optimization techniques and the detection efficiency computation.

2.
Curr Eye Res ; 38(9): 933-44, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23767776

RESUMEN

PURPOSE: Transplantation of autologous corneal stem cells in not possible in cases of bilateral limbal stem cell deficiency (LSCD). To restore the ocular surface in these patients, an autologous extraocular source of stem cells is desirable to avoid dependence on deceased donor tissue and host immunosuppression of allogenic transplants. While bone marrow-derived mesenchymal stem cells (MSCs) can acquire certain characteristics of corneal epithelial cells, subcutaneous adipose tissue (AT) is more readily available and accessible. The aim of this study was to determine if extraocular human AT-derived MSCs (hAT-MSCs) can acquire in vitro some features of corneal epithelial-like cells. METHODS: hAT-MSCs were isolated from human lipoaspirates and expanded up to 3-4 passages. We studied the immunophenotype of MSCs and demonstrated its multipotent capacity to differentiate toward osteoblasts, adipocytes and chondrocytes. To test the capacity of differentiation of hAT-MSCs toward corneal epithelial-like cells, hAT-MSCs were cultured on substrata of plastic or collagen IV. We used basal culture medium (BM), BM conditioned with human corneal epithelial cells (HCEcBM) and BM conditioned with limbal fibroblasts (LFcBM). RESULTS: The hAT-MSCs incubated for 15 days with HCEcBM acquired more polygonal and complex morphology as evaluated by phase-contrast microscopy and flow cytometry. Additionally, the expression of transforming growth factor-ß receptor CD105 and corneal epithelial marker CK12 got increased as evaluated by flow cytometry, real-time reverse-transcription polymerase chain reaction, western blot and immunostaining. These changes were absent in hAT-MSCs incubated with unconditioned BM or with LFcBM. CONCLUSIONS: Corneal epithelial-like cells can be induced from extraocular hAT-MSCs by subjecting them to an in vitro microenvironment containing conditioning signals derived from differentiated human corneal epithelial cells. Our results suggest that hAT-MSCs could provide a novel source of stem cells that hold the potential to restore sight lost in patients suffering from bilateral ocular surface failure due to LSCD.


Asunto(s)
Tejido Adiposo/citología , Trasplante de Córnea/métodos , Epitelio Corneal/citología , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Acondicionamiento Pretrasplante/métodos , Diferenciación Celular , Supervivencia Celular , Células Cultivadas , Microambiente Celular/fisiología , Epitelio Corneal/fisiología , Humanos , Inmunofenotipificación , Técnicas In Vitro , Limbo de la Córnea/citología , Células Madre Mesenquimatosas/fisiología , Transcriptoma
3.
J Immunol Methods ; 389(1-2): 61-8, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23318778

RESUMEN

Culturing of human retinal pigment epithelial cells (hRPE) is the initial step in cell therapy of some retinal diseases. To transfer these cells into clinical use, it is necessary to guarantee that they are well differentiated and contamination free. Fluorescence microscopy is the easiest method to do this, but it is associated with operator subjectivity, and the results are highly variable. The aim of this study was to demonstrate the practicality of implementing flow cytometry (FC) analysis to determine the purity of human RPE primary cell cultures. An ARPE19 cell line, human skin fibroblasts, hRPE, and human corneal epithelial cells were analysed by FC to determine the percentage of the hRPE population expressing RPE65 and epithelial and fibroblast proteins. The cell viability and DNA content also were determined. FC analysis showed that the hRPE cells were healthy, stable, and expressed RPE65 protein in the study working conditions. The density of RPE65 protein expression decreased during passages 2 to 10, which was confirmed using a Western blot technique. However, the hRPE cells did not express the 112-kDa epithelial and fibroblast proteins in the current working conditions. These findings suggested that FC facilitates a detailed analysis of human RPE primary cell cultures, a necessary step in developing new cell therapies for retinal diseases.


Asunto(s)
Citometría de Flujo/métodos , Epitelio Pigmentado de la Retina/citología , Línea Celular , Supervivencia Celular/fisiología , Células Epiteliales/citología , Citometría de Flujo/normas , Humanos , Cultivo Primario de Células/métodos , cis-trans-Isomerasas/análisis
4.
Exp Eye Res ; 93(6): 956-62, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21777584

RESUMEN

Retinal pigment epithelial (RPE) cells are currently in the "spotlight" of cell therapy approaches to some retinal diseases. The analysis of the expressed proteins of RPE primary cells is an essential step for many of these approaches. But the emission of autofluorescence by RPE cells produces higher background noise interference thereby creating an impediment to this analysis. Trypan Blue (TB), a routinely used counterstain, has the capacity to quench this autofluorescence, if it is used in optimized concentration. The results from the method developed in our study indicate that incubation of the cultured RPE cells with 20 µg/ml of TB after immunolabelling (post-treatment) as well as incubation of the retinal tissue specimens with same concentration before paraffin embedding, sectioning and immunolabelling (pre-treatment) can be applied to effectively quench the autofluorescence of RPE cells. Thus it can facilitate the evaluation of expressed cellular proteins in experimental as well as in pathological conditions, fulfilling the current requirement for developing a method which can serve to eliminate the autofluorescence of the cells, not only in cell cultures but also in tissues samples. This method should significantly increase the quality and value of RPE cell protein analysis, as well as other cell protein analysis performed by Flow cytometry (FC) and Immunohistochemistry (IHC) techniques.


Asunto(s)
Colorantes , Células Epiteliales/metabolismo , Proteínas del Ojo/metabolismo , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Epitelio Pigmentado de la Retina/metabolismo , Coloración y Etiquetado/métodos , Azul de Tripano , Animales , Artefactos , Células Cultivadas , Adhesión en Parafina , Reproducibilidad de los Resultados , Porcinos
5.
Invest Ophthalmol Vis Sci ; 52(7): 4819-28, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21474769

RESUMEN

PURPOSE: To assess cell viability and cell cycle kinetics of the conjunctival epithelium and to identify intraepithelial lymphocyte (IEL) subsets in patients with evaporative-type dry eye disease (ev-DED) caused by meibomian gland dysfunction and in healthy subjects. The effect of topical treatment and correlations between clinical symptoms and signs and epithelial and immune variables were also determined. METHODS: Inferior fornix and tarsal conjunctival cells were collected by brush cytology (BC) from patients with mild to moderate ev-DED (n = 23) before and after 2 months of treatment that included lid hygiene, artificial tears, and a 3-week course of topical unpreserved steroids. Healthy subjects (n = 17) served as controls. Two symptom questionnaires were self-answered, and multiple DED-related clinical tests were performed. Epithelial or immune lineage, IEL subtypes, cell viability, apoptosis, and cell cycle stage of the BC-recovered cells were determined by flow cytometry. RESULTS: Conjunctival cell viability was dramatically decreased in ev-DED patients compared with controls. For both groups, two different cell populations, differentiated by cell size and complexity, were present in the apoptosis assay. After 2 months of treatment, 87% of subjects subjectively improved, CD8 cells increased, and CD4 cells and the CD4/CD8 ratio significantly decreased. The pretreatment and posttreatment proliferative capacity of the conjunctival epithelium was significantly lower in ev-DED patients than in healthy controls. CONCLUSIONS: The viability and proliferative capacity of ev-DED patient conjunctival cells were reduced, suggesting a potential role for these parameters as disease biomarkers.


Asunto(s)
Proliferación Celular , Conjuntiva/patología , Síndromes de Ojo Seco/patología , Células Epiteliales/patología , Inmunidad Celular , Adulto , Anciano , Apoptosis , Ciclo Celular , Conjuntiva/inmunología , Síndromes de Ojo Seco/inmunología , Células Epiteliales/inmunología , Femenino , Citometría de Flujo , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
6.
Science ; 329(5993): 804, 2010 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-20651117

RESUMEN

We report on the detection in southern Egypt of an impact crater 45 meters in diameter with a pristine rayed structure. Such pristine structures are typically observed on atmosphereless rocky or icy planetary bodies in the solar system. This feature and the association with an iron meteorite impactor and shock metamorphism provides a unique picture of small-scale hypervelocity impacts on Earth's crust. Contrary to current geophysical models, ground data indicate that iron meteorites with masses of the order of tens of tons can penetrate the atmosphere without substantial fragmentation.

7.
Int. braz. j. urol ; 33(6): 785-794, Nov.-Dec. 2007. ilus, tab
Artículo en Inglés | LILACS | ID: lil-476642

RESUMEN

INTRODUCTION: The corpora cavernosa are cylindrical vessels containing fluid under pressure. Thus, if cavernous wall resistance decreases, the radius increases and internal pressure decreases (LaPlace's law). We reasoned that if we decrease the corpus cavernosum radius, by excising a strip from each tunica albuginea, intracavernous pressure would increase during erection. MATERIALS AND METHODS: We treated with this procedure, four patients (mean age 41.5) with long-standing erectile dysfunction due to veno-occlusive dysfunction, non-responders to phosphodiesterase-5 inhibitors and intracavernous PGE1 injection. RESULTS: Two months post-surgery, intracavernous PGE1 (40 mcg) induced a satisfactory erection in two patients and a 45 percent and 58 percent tumescence in the other two. PGE1 responders also responded to 100 mg sildenafil. After 100 mg sildenafil and 20 mg tadalafil, the two non-responders had erections that enabled penetration but were short lasting. CONCLUSION: The procedure described could be more effective than cavernous revascularization operations. The results seem to confirm the mathematical assumptions.


Asunto(s)
Adulto , Humanos , Masculino , Persona de Mediana Edad , Tejido Elástico/patología , Impotencia Vasculogénica/cirugía , Pene/cirugía , Velocidad del Flujo Sanguíneo , Tejido Elástico/fisiopatología , Impotencia Vasculogénica/fisiopatología , Periodo Posoperatorio , Pene/irrigación sanguínea
8.
Urol Int ; 79 Suppl 1: 20-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17726348

RESUMEN

Nephrolithiasis has a multifactorial origin, and several disorders may coexist in the same patient. We made a basic and a specific laboratory evaluation. The complete metabolic evaluation consisted of a serum chemistry panel: blood sugar level, complete hemogram, serum electrolytes, GOT, GPT, calcium, phosphate, uric acid, and creatinine levels and RIA dosage of PTH, vitamin D3, cAMP, FT4, FT3 and TSH. The complete analyses of random urinalysis and culture are: (1) dip-stick test: pH, leukocytes/bacteria and Brand's test, and (2) 24-hour urine collection: calcium, magnesium, oxalate, phosphate, citrate, urea, urate, sodium, creatinine, chloride, potassium. It is possible with these tests to identify secondary causes of nephrolithiasis and uncover coexisting problems that may have an impact on patient management. The future for diagnosis, prevention and therapy will be the identification of genetic alterations and related specific dosage.


Asunto(s)
Análisis Químico de la Sangre , Nefrolitiasis/diagnóstico , Urinálisis , Humanos , Nefrolitiasis/sangre , Nefrolitiasis/etiología , Nefrolitiasis/orina , Medición de Riesgo , Factores de Riesgo
9.
Anticancer Res ; 27(2): 1095-104, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17465249

RESUMEN

Androgen deprivation therapy still remains the gold standard in the treatment of advanced prostate cancer. Unfortunately, patients with metastatic prostate cancer treated with androgen deprivation therapy frequently develop androgen-independent prostate cancer. Cytotoxic chemotherapy has not been used routinely and the current standard regimens have not demonstrated any significant alteration in the development of hormone-refractory disease. Recent phase III randomized clinical trials have suggested that docetaxel-based therapy, demonstrating a real increase of survival in treated patients, could represent the new standard treatment for metastatic patients. There is also promising activity of new drug combinations, such as taxanes plus vinca alkaloids, and of classic chemotherapeutic agents plus biological drugs. This review focuses on the current therapies for the treatment of HRPC.


Asunto(s)
Neoplasias de la Próstata/tratamiento farmacológico , Antraciclinas/uso terapéutico , Antimetabolitos Antineoplásicos/uso terapéutico , Antineoplásicos Alquilantes/uso terapéutico , Difosfonatos/uso terapéutico , Estramustina/uso terapéutico , Humanos , Masculino , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Compuestos Organoplatinos/uso terapéutico , Taxoides/uso terapéutico , Alcaloides de la Vinca/uso terapéutico
10.
Recent Results Cancer Res ; 175: 251-65, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17432564

RESUMEN

Prostate cancer is detected today at earlier stages and in younger men than ever before. A lot of men are asymptomatic and also physically and sexually active at diagnosis, and most of them are being treated by curative procedures. These trends have led to increasing numbers of patients undergoing disease management for longer periods of time. For many patients quality of life (QoL) may be just as important as survival. Thus, QoL considerations may well be the critical factor in medical decision-making for most of them. Widespread interest in studying patient-centred outcomes has led to the development of methods for health-related QoL measurements. In fact, many questionnaires have been introduced in clinical practice to assess the impact of QoL in patients (SF-36, CARES, FACT, EORTC QLQ-C30, GRISS, UCLA PCI, PCOS). Herein we evaluate the impact of QoL on patients affected by prostate cancer and treated with watchful waiting, radical prostatectomy, radiotherapy and hormonal therapy; we have also considered the role of supportive care, including the administration of analgesics, antidepressants, corticosteroids, bisphosphonates, antiemetics and stool softeners, together with psychological support. The ultimate goal of QoL research should strongly improve medical care and concretely assist patients and physicians in treatment decision-making.


Asunto(s)
Neoplasias de la Próstata/terapia , Calidad de Vida , Estado de Salud , Humanos , Masculino , Cuidados Paliativos , Neoplasias de la Próstata/psicología
11.
Int Braz J Urol ; 33(6): 785-90; discussion 790-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18199346

RESUMEN

INTRODUCTION: The corpora cavernosa are cylindrical vessels containing fluid under pressure. Thus, if cavernous wall resistance decreases, the radius increases and internal pressure decreases (LaPlace's law). We reasoned that if we decrease the corpus cavernosum radius, by excising a strip from each tunica albuginea, intracavernous pressure would increase during erection. MATERIALS AND METHODS: We treated with this procedure, four patients (mean age 41.5) with long-standing erectile dysfunction due to veno-occlusive dysfunction, non-responders to phosphodiesterase-5 inhibitors and intracavernous PGE1 injection. RESULTS: Two months post-surgery, intracavernous PGE1 (40 mcg) induced a satisfactory erection in two patients and a 45% and 58% tumescence in the other two. PGE1 responders also responded to 100 mg sildenafil. After 100 mg sildenafil and 20 mg tadalafil, the two non-responders had erections that enabled penetration but were short lasting. CONCLUSION: The procedure described could be more effective than cavernous revascularization operations. The results seem to confirm the mathematical assumptions.


Asunto(s)
Tejido Elástico/patología , Impotencia Vasculogénica/cirugía , Pene/cirugía , Adulto , Velocidad del Flujo Sanguíneo , Tejido Elástico/fisiopatología , Humanos , Impotencia Vasculogénica/fisiopatología , Masculino , Persona de Mediana Edad , Pene/irrigación sanguínea , Periodo Posoperatorio
12.
Anticancer Res ; 26(4B): 3151-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16886649

RESUMEN

The proportion of prostate cancer diagnosed at localized stages increased from 56.7% to 74. 0% between 1973 and 1993 ("stage migration"). A corresponding increase in the number of radical prostatectomies performed each year was also noted. Nomograms are mathematical algorithms derived from statistical models that are used to predict outcomes for an individual patient, or for groups of patients. In fact, careful pre-operative patient and tumor selection before radical prostatectomy is mandatory. Locally advanced prostate cancer is defined as tumor that has extended clinically beyond the prostatic capsule, with invasion of the pericapsular tissue, apex, bladder neck or seminal vescicle, but without lymph node involvement or distant metastasis. It is estimated that 12-15% of prostate cancer are stage T3. Overstaging or understaging of this cancer is common. Correct staging of clinical T3 disease is even more difficult and both overstaging pT2 and understaging pT4 or pN+ are common. The goals of treatment for T3 tumors are to cure the disease, prolong survival or metastasis-free survival and improve the quality of life. The authors reviewed the most important studies, investigated radical prostatectomy as monotherapy for locally advanced prostate cancer and the integration of surgery with hormonal treatment. The EAU guidelines on prostate cancer state that radical prostatectomy in locally advanced disease is an option for selected patients with small T3, PSA <20 ng/ml, Gleason score <8 and a life expectancy > 10 years. Ten to 15% of clinical T3 are overstaged as pT2. This may lead to the possibility of curing these patients with surgery as the monotherapy. The increased use of nomograms and increased knowledge of recognized prognostic factors could lead to the selection of a large number of patients, often with a long life expectancy, who could benefit from surgical treatment.


Asunto(s)
Neoplasias de la Próstata/cirugía , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Prostatectomía , Neoplasias de la Próstata/patología , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA