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1.
Exp Eye Res ; 193: 107980, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32088241

RESUMEN

The lamina cribrosa (LC) in glaucoma is with augmented production of extracellular matrix proteins (ECM) and connective tissue fibrosis. Fundamental pathological mechanisms for this fibrosis comprise fibrotic growth factors and oxidative stress. Transient receptor potential canonical channels (TRPC) channels play a key role in ECM fibrosis. Here, we study TRPC expression in glaucomatous LC cells, and investigate the role of TRPC in oxidative stress induced-profibrotic ECM gene transcription and cell proliferation in normal LC cells. Age-matched human LC cells (normal, n = 3 donors; glaucoma, n = 3 donors) were used. Hydrogen peroxide (H2O2, 100 µM), was used to induce oxidative stress in LC cells in the presence or absence of the pan TRPC inhibitor SKF96365 (10 µM) or knockdown of TRPC1/6 with siRNA. After treatments, ECM gene transcription, LC cell viability and proliferation and the phosphorylation of the transcription factor NFATc3, were measured using real time RT-PCR, colorimetric cell counting with the methyl-thiazolyl tetrazolium salt (MTS) assay, and Western immunoblotting, respectively. Results showed that TRPC1/C6 transcript and protein expression levels were significantly (p < 0.05) enhanced in glaucoma LC cells. Both SKF96365 and siRNA-TRPC1/C6 treatments significantly reduced the oxidative stress induced-ECM gene expression (transforming growth factor-ß1 (TGFß1), alpha smooth muscle actin (α-SMA), and collagen type 1A1 (Col1A1)), and cell proliferation in normal and glaucoma LC cells. Also, SKF96365 treatment inhibited the H2O2-induced NFATc3 protein dephosphorylation in LC cells. In conclusion, TRPC1/C6 expression is enhanced in glaucoma LC cells. These channels may contribute to oxidative stress-induced ECM gene transcription and cell proliferation in normal and glaucoma LC cells through Ca2+-NFATc3 signaling pathway mechanism. TRPC1 and TRPC6 channels could be important therapeutic targets to prevent ECM remodeling and fibrosis development in glaucoma optic neuropathy.


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Regulación de la Expresión Génica , Glaucoma/genética , Disco Óptico/patología , ARN/genética , Canales Catiónicos TRPC/genética , Canal Catiónico TRPC6/genética , Western Blotting , Proliferación Celular , Células Cultivadas , Proteínas de la Matriz Extracelular/metabolismo , Perfilación de la Expresión Génica , Glaucoma/metabolismo , Glaucoma/patología , Humanos , Disco Óptico/metabolismo , Canales Catiónicos TRPC/biosíntesis , Canal Catiónico TRPC6/biosíntesis , Transcripción Genética
2.
Mol Vis ; 17: 1182-91, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21617752

RESUMEN

PURPOSE: Oxidative stress is implicit in the pathological changes associated with glaucoma. The purpose of this study was to compare levels of oxidative stress in glial fibrillary acid-negative protein (GFAP) lamina cribrosa (LC) cells obtained from the optic nerve head (ONH) region of 5 normal (NLC) and 4 glaucomatous (GLC) human donor eyes and to also examine mitochondrial function and calcium homeostasis in this region of the ONH. METHODS: Intracellular reactive oxygen species (ROS) production was examined by a thiobarbituric acid reactive substances (TBARS) assay which measures malondialdehyde (MDA), a naturally occurring product of lipid peroxidation and is used as an indicator of oxidative stress. Mitochondrial membrane potential (MMP) and intracellular calcium ([Ca(2+)](i)) levels were evaluated by flow cytometry using the JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetrabenzimidazolecarbocyanine iodide) and fluo-4/AM probes respectively. Anti-oxidant and Ca(2+) transport system gene and protein expression were determined by real time polymerase chain reaction (RT-PCR) using gene-specific primer/probe sets and western immunoblotting, respectively. RESULTS: Intracellular ROS production was increased in GLC compared to NLC (27.19 ± 7.05 µM MDA versus 14.59 ± 0.82 µM MDA, p < 0.05). Expression of the anti-oxidants Aldo-keto reductase family 1 member C1 (AKR1C1) and Glutamate cysteine ligase catalytic subunit (GCLC) were significantly lower in GLC (p = 0.02) compared to NLC control. MMP was lower in GLC (57.5 ± 6.8%) compared to NLC (41.8 ± 5.3%). [Ca(2+)](i) levels were found to be higher (p < 0.001) in GLC cells compared to NLC. Expression of the plasma membrane Ca(2+)/ATPase (PMCA) and the sodium-calcium (NCX) exchangers were lower, while intracellular sarco-endoplasmic reticulum Ca(2+)/ATPase 3 (SERCA) expression was significantly higher in GLC compared to NLC. Subjection of NLC cells to oxidative stress (200 µM H(2)0(2)) reduced expression of Na(+)/Ca2(+) exchanger 1 (NCX 1), plasma membrane Ca2+ ATPase 1 (PMCA 1), and PMCA 4 as determined by RT-PCR. CONCLUSIONS: Our data finds evidence of oxidative stress, mitochondrial dysfunction and impaired calcium extrusion in GLC cells compared to NLC cells and suggests their importance in the pathological changes occurring at the ONH in glaucoma. Future therapies may target reducing oxidative stress and / or [Ca(2+)](i).


Asunto(s)
Astrocitos/metabolismo , Calcio/metabolismo , Lámina Limitante Posterior/metabolismo , Glaucoma/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Mitocondrias/metabolismo , Disco Óptico/metabolismo , 20-Hidroxiesteroide Deshidrogenasas/genética , 20-Hidroxiesteroide Deshidrogenasas/metabolismo , Anciano , Anciano de 80 o más Años , Astrocitos/citología , Western Blotting , Estudios de Casos y Controles , Técnicas de Cultivo de Célula , Lámina Limitante Posterior/citología , Lámina Limitante Posterior/patología , Citometría de Flujo , Perfilación de la Expresión Génica , Glaucoma/patología , Proteína Ácida Fibrilar de la Glía/genética , Glutamato-Cisteína Ligasa/genética , Glutamato-Cisteína Ligasa/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Potencial de la Membrana Mitocondrial , Disco Óptico/patología , Estrés Oxidativo , ATPasas Transportadoras de Calcio de la Membrana Plasmática/genética , ATPasas Transportadoras de Calcio de la Membrana Plasmática/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
3.
PLoS One ; 16(7): e0253802, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34228739

RESUMEN

Microplastic continues to be an environmental concern, especially for filter feeding bivalves known to ingest these particles. It is important to understand the effects of microplastic particles on the physiological performance of these bivalves and many studies have investigated their impact on various physiological processes. This study investigated the effects of microplastic (10 µm) on digestive enzyme (amylase) activity of Mytilus galloprovincialis at 55,000 and 110,000 microplastic particles/L under laboratory conditions. Additionally, our study measured the expression of an isoform of Hsp70 in the gills to assess whether or not these particles may cause protein denaturation. Results revealed that this regime negatively affect the ability of M. galloprovincialis to digest starch under high food conditions but not low food conditions. Exposure to extreme levels of microplastic raised amylase activity. Furthermore, Hsp70 transcript abundance was not elevated in treatment mussels. These results show that mussels may be resilient to current microplastic pollution levels in nature.


Asunto(s)
Amilasas/metabolismo , Microplásticos/toxicidad , Mytilus edulis/enzimología , Contaminantes Químicos del Agua/toxicidad , Animales , Pruebas de Enzimas , Desnaturalización Proteica , Almidón/metabolismo , Pruebas de Toxicidad Subaguda
4.
Br J Cancer ; 103(10): 1510-7, 2010 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-20959828

RESUMEN

OBJECTIVE: This study examines the prognostic significance of human papillomavirus (HPV) in patients with locally advanced oropharyngeal squamous cell carcinoma (SCC) treated primarily with surgery or definitive radiotherapy. METHODS: One hundred and ninety-eight patients with Stage 3/4 SCC were followed up for recurrence in any form or death from any cause for between 1 and 235 months after diagnosis. HPV status was determined using HPV E6-targeted multiplex real-time PCR/p16 immunohistochemistry. Determinants of recurrence and mortality hazards were modelled using Cox's regression with censoring at follow-up dates. RESULTS: Forty-two per cent of cancers were HPV-positive (87% type 16). HPV predicted loco-regional control, event-free survival and overall survival in multivariable analysis. Within the surgery with adjuvant radiotherapy (n=110), definitive radiotherapy-alone (n=24) and definitive radiotherapy with chemotherapy (n=47) groups, patients with HPV-positive cancers were one-third or less as likely to have loco-regional recurrence, an event or to die of any cause as those with HPV-negative cancers after adjusting for age, gender, tumour grade, AJCC stage and primary site. The 14 patients treated with surgery alone were considered too few for multivariable analysis. CONCLUSION: HPV status predicts better outcome in oropharyngeal cancer treated with surgery plus adjuvant radiotherapy as well as with definitive radiation therapy±chemotherapy.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Papillomavirus Humano 6/aislamiento & purificación , Neoplasias Orofaríngeas/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Neoplasias Orofaríngeas/tratamiento farmacológico , Neoplasias Orofaríngeas/mortalidad , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/cirugía , Valor Predictivo de las Pruebas , Recurrencia , Neoplasias de la Lengua/patología , Neoplasias de la Lengua/terapia , Neoplasias Tonsilares/patología , Neoplasias Tonsilares/terapia
5.
Osteoporos Int ; 20(4): 507-18, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18758880

RESUMEN

SUMMARY: In this systematic review, we summarize risk factors for low bone mineral density and bone loss in healthy men age 50 years or older. Consistent risk factors were: age, smoking, low weight, physical/functional limitations, and previous fracture. Data specific to men has clinical and policy implications. INTRODUCTION: Osteoporosis is a significant health care problem in men as well as women, yet the majority of evidence on diagnosis and management of osteoporosis is focused on postmenopausal women. The objective of this systematic review is to examine risk factors for low bone mineral density (BMD) and bone loss in healthy men age 50 years or older. MATERIALS AND METHODS: A systematic search for observational studies was conducted in MEDLINE, Cochrane Database of Systematic Reviews, DARE, CENTRAL, CINAHL and Embase, Health STAR. The three main search concepts were bone density, densitometry, and risk factors. Trained reviewers assessed articles using a priori criteria. RESULTS: Of 642 screened abstracts, 299 articles required a full review, and 25 remained in the final assessment. Consistent risk factors for low BMD/bone loss were: advancing age, smoking, and low weight/weight loss. Although less evidence was available, physical/functional limitations and prevalent fracture (after age 50) were also associated with low BMD/bone loss. The evidence was inconsistent or weak for physical activity, alcohol consumption, calcium intake, muscle strength, family history of fracture/osteoporosis, and height/height loss. CONCLUSION: In this systematic review, we identified several risk factors for low BMD/bone loss in men that are measurable in primary practice.


Asunto(s)
Osteoporosis/etiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Densidad Ósea , Fracturas Óseas/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Proyectos de Investigación , Factores de Riesgo , Fumar/efectos adversos , Pérdida de Peso/fisiología
6.
Br J Oral Maxillofac Surg ; 44(3): 187-92, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16095776

RESUMEN

The aim of this study was to evaluate (by postal questionnaire) quality of life and function in patients who have had resections of oral cancer and reconstruction by radial forearm flaps. Between October 1987 and December 2002, 258 patients had reconstructions by radial forearm flaps after resection of tumours in the oral cavity. Of these, 139 surviving patients were identified from the database and were sent questionnaires comprising five sections: Functional Assessment of Cancer Therapy-General (FACT-G) and -Head and Neck (FACT-HN); University of Washington Quality of Life Scale (UWQoL); Performance Status Scale for Head and Neck Cancer (PSS-HN); and the final section addressed dental rehabilitation and morbidity at the donor site. Sixty-three questionnaires (45%) were returned. In 17 (27%), parts of the questionnaire were incomplete. The median UWQoL score was 623/900, FACT-G was 92/108, FACT-HN was 31/48, and PSS-HN showed that eating in public, understandability of speech and normality of diet were 75/100, 75/100 and 50/100, respectively. The effect of stage and site on quality of life and function did not reach statistical significance. The effect of radiotherapy on speech (p=0.036) and diet (p=0.007) was significant. Patients who worried about their cancer returning had a lower UWQoL score (p=0.016). Ninety percent regarded their arm as disfigured, but 81% felt comfortable wearing short-sleeved shirts. Sensation and function of the hand were reported as normal in 87 and 92%, respectively. We conclude that patients who have had oral cancer have a persistent reduction in quality of life and function long after completion of treatment. The effects can be assessed by postal questionnaire, but the low rate of return (45%) and difficulties with completion reduce the quality of the data. Quality of life and function are essential components of improvements in outcome.


Asunto(s)
Neoplasias de la Boca , Calidad de Vida , Sobrevivientes , Adulto , Anciano , Anciano de 80 o más Años , Métodos Epidemiológicos , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/psicología , Neoplasias de la Boca/cirugía , Calidad de Vida/psicología , Recuperación de la Función , Colgajos Quirúrgicos , Sobrevivientes/psicología
7.
Protein Eng Des Sel ; 29(6): 231-243, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27160179

RESUMEN

Non-native protein aggregation is a ubiquitous challenge in the production, storage and administration of protein-based biotherapeutics. This study focuses on altering electrostatic protein-protein interactions as a strategy to modulate aggregation propensity in terms of temperature-dependent aggregation rates, using single-charge variants of human γ-D crystallin. Molecular models were combined to predict amino acid substitutions that would modulate protein-protein interactions with minimal effects on conformational stability. Experimental protein-protein interactions were quantified by the Kirkwood-Buff integrals (G22) from laser scattering, and G22 showed semi-quantitative agreement with model predictions. Experimental initial-rates for aggregation showed that increased (decreased) repulsive interactions led to significantly increased (decreased) aggregation resistance, even based solely on single-point mutations. However, in the case of a particular amino acid (E17), the aggregation mechanism was altered by substitution with R or K, and this greatly mitigated improvements in aggregation resistance. The results illustrate that predictions based on native protein-protein interactions can provide a useful design target for engineering aggregation resistance; however, this approach needs to be balanced with consideration of how mutations can impact aggregation mechanisms.


Asunto(s)
Mutagénesis Sitio-Dirigida , Agregado de Proteínas , gamma-Cristalinas/química , gamma-Cristalinas/genética , Clonación Molecular , Escherichia coli/genética , Humanos , Modelos Moleculares , Mutación Puntual , Mapas de Interacción de Proteínas , Estabilidad Proteica , Electricidad Estática , Temperatura , gamma-Cristalinas/metabolismo
8.
Leukemia ; 2(8): 496-502, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3412023

RESUMEN

Human herpesvirus 6 (HHV-6) is a recently discovered virus which has not been causally linked to any particular disease. In order to investigate the possible role of this virus in the pathogenesis of lymphoid malignancies, we examined tissue samples from 117 patients for the presence of HHV-6-specific DNA sequences. Two cases of non-Hodgkin's lymphoma were found to be positive. One patient had a T cell lymphoma and a preceding history of angioimmunoblastic lymphadenopathy; the other had a B cell lymphoma occurring in the context of Sjögren's syndrome. HHV-6 has been isolated previously from a patient with angioimmunoblastic lymphadenopathy, and viral sequences have been identified in another patient with Sjögren's syndrome and B cell lymphoma. The relationship between HHV-6 and these conditions therefore warrants further investigation.


Asunto(s)
ADN Viral/análisis , Herpesviridae/genética , Linfoma no Hodgkin/microbiología , Anciano , Secuencia de Bases , Femenino , Humanos , Linfadenopatía Inmunoblástica/etiología , Linfoma no Hodgkin/etiología , Persona de Mediana Edad , Síndrome de Sjögren/etiología
9.
Br J Oral Maxillofac Surg ; 43(3): 199-204, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15888352

RESUMEN

BACKGROUND: The aim of this study was to report the applications, complications, and limitations of the radial forearm flap when used for reconstruction after excision of cancers in the mouth. PATIENTS AND METHODS: We reviewed records in our database from October 1987 to December 2002; a total of 505 patients had surgical defects of the head and neck reconstructed with a radial forearm flap: 258 patients had oral cancers, of whom 173 were men and 85 women, median age was 70 years. Five patients had two reconstructions (total 263), of which 247 were fasciocutaneous and 16 osseofasciocutaneous flaps. Mucosal squamous carcinoma accounted for 97% of the primary cancers. RESULTS: There were nine failures of the flap (3.4%) and four episodes of partial necrosis. Four patients (2%) died within 30 days of operation. Orocutaneous fistulas appeared in nine patients (3.4%), 10 patients had wound infections, and nine had haematomas. The nine failed flaps were replaced by a second free flap in one patient, a pectoralis major flap in three, a buccinator myomucosal flap in one, a skin graft in one, and the remaining three defects healed by secondary intention. There was one failure and one partial failure among the 16 osseofasciocutaneous flaps.


Asunto(s)
Trasplante Óseo/métodos , Procedimientos Quirúrgicos Orales/métodos , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Fístula Cutánea/etiología , Fascia/trasplante , Femenino , Antebrazo , Hematoma/etiología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/cirugía , Necrosis , Fístula Oral/etiología , Procedimientos Quirúrgicos Orales/efectos adversos , Músculos Pectorales/trasplante , Procedimientos de Cirugía Plástica/efectos adversos , Reoperación , Estudios Retrospectivos , Trasplante de Piel/métodos , Colgajos Quirúrgicos/efectos adversos , Infección de la Herida Quirúrgica/etiología , Tasa de Supervivencia , Resultado del Tratamiento
10.
Ir J Med Sci ; 174(2): 36-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16094911

RESUMEN

AIMS: This study was designed to document the changing trends in ophthalmic surgery in acute public hospitals in the Republic of Ireland over the years 1994 to 2001. METHOD: We obtained Hospital In-Patient Enquiry (HIPE) data returned from the major acute public hospitals to the Economic and Social Research Institute. We searched for cataracts, glaucoma, retinal detachment, strabismus, corneal transplant and repair of perforating injuries of the globe. RESULTS: There was a 24% increase in the total number of the searched operations occurring during the study period, from 8,857 procedures in 1994 to 11,005 in 2001. In 2001, cataract surgery alone counted for 82% of all procedures performed. There was a large increase in cataract (49%) and vitreo-retinal procedures (41%) reported between 1994 and 2001. Conversely, a large fall in trabeculectomy (67%), strabismus (63%) and corneal transplant (52%) procedures occurred during the study period. CONCLUSION: These data suggest that surgical numbers in ophthalmology in Ireland are increasing and the relative proportions are changing.


Asunto(s)
Hospitales Públicos/estadística & datos numéricos , Procedimientos Quirúrgicos Oftalmológicos/estadística & datos numéricos , Revisión de Utilización de Recursos/estadística & datos numéricos , Humanos , Irlanda
11.
Biomed Res Int ; 2015: 418159, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26557667

RESUMEN

INTRODUCTION: Altered ocular perfusion and vascular dysregulation have been reported in glaucoma. The aim of this paper was to evaluate the vascular response to a hypercapnic stimulus. METHODS: Twenty normal tension glaucoma (NTG) patients and eighteen age- and gender-matched controls had pulsatile ocular blood flow (POBF) measurements, systemic cardiovascular assessment, and laser Doppler digital blood flow (DBF) assessed. Measurements were taken at baseline, after 10-minutes rest, in the stable sitting and supine positions and following induction and stabilization of hypercapnia, which induced a 15% increase in end-tidal pCO2. The POBF response to hypercapnia was divided into high (>20%) and low responders (<20%). RESULTS: 65% of NTG patients had a greater than 41% increase in POBF following CO2 rebreathing (high responders). These high responders had a lower baseline POBF, lower baseline DBF, and a greater DBF response to thermal stimulus. CONCLUSION: NTG patients that have a greater than 20% increase in POBF after a hypercapnic stimulus have lower baseline POBF and DBF values. This suggests that there is impaired regulation of blood flow in a significant subgroup of NTG patients. This observation may reflect a generalised dysfunction of the vascular endothelium.


Asunto(s)
Hipercapnia/fisiopatología , Glaucoma de Baja Tensión/sangre , Glaucoma de Baja Tensión/fisiopatología , Velocidad del Flujo Sanguíneo/fisiología , Estudios de Casos y Controles , Ojo/fisiopatología , Femenino , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Flujo Pulsátil/fisiología , Flujo Sanguíneo Regional/fisiología
12.
Br J Ophthalmol ; 99(7): 1009-14, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25795916

RESUMEN

PURPOSE: This study examines the effect of the L-type calcium channel blocker verapamil on mechanical strain-induced extracellular matrix genes in optic nerve head lamina cribrosa (LC) cells. METHODS: Changes in LC cell intracellular calcium [Ca(2+)]i following hypotonic cell membrane stretch were measured with the fluorescent probe fura-2/AM. Fluorescence intensity was measured, after labelling, by calcium (Ca2+) imaging confocal microscopy. Confluent human LC cell cultures were serum starved for 24 h prior to exposure to cyclical mechanical strain (1 Hz, 15%) for 24 h in the presence or absence of verapamil (10 mm). Transforming growth factor-ß 1 (TGF-ß1), collagen 6A3 (COL6A3) and chondroitin sulfate proteoglycan 2 (CSPG2) mRNA expression levels were assessed by quantitative RT-PCR. RESULTS: Hypotonic cell membrane stretch of LC cells from normal donors significantly increased [Ca2+]i (p<0.05). Exposure to cyclical mechanical strain (15% strain) produced a statistically significant increase in the three matrix genes that were examined (TGF-ß1, COL6A3 and CSPG2). This response in both cyclical and mechanical stretch was significantly reduced by pretreating LC cells with the L-type calcium channel blocker verapamil (p<0.05). CONCLUSIONS: This study provides evidence of a novel mechanotransduction pathway linking mechanical strain, cation channel function and the induction of LC cell matrix gene transcription. This highlights the potential involvement of calcium influx in the activation of matrix remodelling responses in the optic nerve head and supports the rationale that calcium channel blockers may attenuate disease progression in glaucoma.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/fisiología , Matriz Extracelular/genética , Regulación de la Expresión Génica/fisiología , Mecanotransducción Celular/efectos de los fármacos , Verapamilo/farmacología , Anciano , Anciano de 80 o más Años , Calcio/metabolismo , Células Cultivadas , Colágeno Tipo VI/genética , Fura-2/análogos & derivados , Fura-2/metabolismo , Humanos , Mecanotransducción Celular/fisiología , Microscopía Confocal , Disco Óptico/citología , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Estrés Mecánico , Factor de Crecimiento Transformador beta1/genética , Versicanos/genética
13.
J Clin Endocrinol Metab ; 85(8): 2733-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10946873

RESUMEN

The world's highest incidence of thyroid cancer has been reported among females in New Caledonia, a French overseas territory in the Pacific located between Australia and Fiji. To date, no molecular genetic studies in this population are available. Over the past few years, the oncogenic rearrangement of the ret protooncogene (ret/ptc) has been studied in papillary carcinomas in different populations. In this study, we investigated the prevalence and distribution of ret/ptc1, 2, and 3 in papillary thyroid carcinoma from the New Caledonian population and compared the pattern with that of an Australian population. Fresh-frozen and paraffin-embedded papillary carcinomas from 27 New Caledonian and 20 Australian patients were examined for ret rearrangements by means of RT-PCR with primers flanking the chimeric region, followed by hybridization with radioactive probes. ret/ptc was present in 70% of the New Caledonian and in 85% of the Australian samples. Multiple rearrangements were detected and confirmed by sequencing in 19 cases, 4 of which had 3 types of rearrangements in the same tumor. This study demonstrates a high prevalence of ret/ptc in New Caledonian and Australian papillary carcinoma. The findings of multiple ret/ptc in the same tumor suggest that some thyroid neoplasms may indeed be polyclonal.


Asunto(s)
Carcinoma Papilar/genética , Proteínas de Drosophila , Reordenamiento Génico , Proteínas de la Membrana/genética , Proteínas Oncogénicas/genética , Fosfoproteínas Fosfatasas/genética , Proteínas , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas de Saccharomyces cerevisiae , Neoplasias de la Tiroides/genética , Adolescente , Adulto , Anciano , Australia/epidemiología , Secuencia de Bases , Carcinoma Papilar/epidemiología , Femenino , Humanos , Incidencia , Péptidos y Proteínas de Señalización Intracelular , Masculino , Persona de Mediana Edad , Nueva Caledonia/epidemiología , Proteínas de Fusión Oncogénica , Receptores Patched , Receptor Patched-1 , Mutación Puntual , Proteína Fosfatasa 2 , Proteína Fosfatasa 2C , Proteínas Tirosina Quinasas , Proteínas Proto-Oncogénicas c-ret , Receptores de Superficie Celular , Neoplasias de la Tiroides/epidemiología
14.
Int J Radiat Oncol Biol Phys ; 13(6): 825-32, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3583851

RESUMEN

Two hundred fifty radical neck dissections, undertaken for mucosal squamous carcinomas of the head and neck, were reviewed with reference to pathological findings and their clinical implications. No major differences in descriptive surgical pathology were established between irradiated and non-irradiated resections. In general, irradiated dissections had lower total node counts and somewhat fewer nodal metastases involving a smaller number of different nodal groups. The topography of nodal deposits was similar in irradiated and non-irradiated resections. Palpable keratin granulomas (without intact tumor) were almost confined to irradiated patients. Transcapsular spread of tumor from involved lymph nodes was common: it was demonstrated in 160/188 'positive' dissections (85%) and was subclassified as 'macroscopic' in 90 and 'microscopic' in 70. The incidence and extent of transcapsular spread was similar in irradiated and nonirradiated resections. It was more frequently observed in association with large nodal masses but it was also regularly found with small nodal deposits less than 3 cm in diameter. Statistical analyses showed strong associations (p less than 0.0005) between the presence and/or extent of transcapsular spread and subsequent recurrence in the operated neck and overall survival. The predictive value of other clinical and pathological features vis-a-vis local neck recurrence such as numbers of involved nodal groups was weaker. Macroscopic transcapsulr spread emerges as the major prognostic factor for recurrent disease in the neck (p less than 0.0001). Attention is drawn to the advantages of accurate descriptive categories ('macroscopic', 'microscopic') for this critical prognostic feature.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Humanos , Escisión del Ganglio Linfático , Cuello , Pronóstico
15.
Aliment Pharmacol Ther ; 6(1): 51-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1347468

RESUMEN

The clinical tolerance to three 5-aminosalicylic acid (5-ASA) releasing preparations (mesalazine, olsalazine and balsalazide) was assessed in a consecutive series of 43 patients with inflammatory bowel disease who were intolerant to sulphasalazine. The relative contributions to the side-effects of sulphasalazine made by its two components, 5-ASA and sulphapyridine, were also assessed in these patients. Thirty-nine (91%) patients were able to tolerate at least one of the three 5-ASA preparations. Only four (9%) patients were intolerant to all preparations, having adverse reactions previously experienced with sulphasalazine and presumably related to 5-ASA rather than sulphapyridine. The clinical tolerance to mesalazine (63%), olsalazine (70%) and balsalazide (70%) was similar, and tolerance to one drug only was found in nine (18%) patients. The commonest adverse reactions associated with 5-ASA preparations were gastrointestinal. Diarrhoea was a problem in five patients during treatment with olsalazine and three each while on mesalazine and balsalazide. Allergic reactions from 5-ASA preparations were uncommon; of ten patients with rash following sulphasalazine only one developed a rash with mesalazine. The results of this study indicate that the vast majority of patients with inflammatory bowel disease can be managed with at least one of these four 5-ASA containing preparations and that the side-effects of sulphasalazine are multifactorial in aetiology, some being due to the parent molecule, and some to one of its two metabolites, 5-ASA and sulphapyridine.


Asunto(s)
Ácidos Aminosalicílicos/efectos adversos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Sulfasalazina/efectos adversos , Ácidos Aminosalicílicos/administración & dosificación , Hipersensibilidad a las Drogas , Femenino , Humanos , Masculino , Mesalamina , Fenilhidrazinas , Sulfapiridina/efectos adversos
16.
Autoimmunity ; 7(2-3): 97-108, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2104186

RESUMEN

Fifteen women with positive islet cell antibodies were identified in a group of 115 consecutive patients found to have impaired glucose tolerance in pregnancy. These subjects were postulated to be at increased risk of later developing type 1 diabetes mellitus. They were examined post--partum for HLA types known to be associated with this disease and for any increase in Interleukin 2 receptor expression or alteration of T cell subsets of possible relevance to its pathogenesis. Fifteen women negative for islet antibodies and with normal glucose tolerance during previous pregnancy and 15 women with a normal fasting plasma glucose who had never been pregnant were studied as controls. Using flow cytometric techniques a significant increase in both the number and proportion of activated (Interleukin 2 receptor, CD25) lymphocytes in the peripheral blood of women who had islet cell antibodies and previous impaired glucose tolerance in pregnancy was found (0.14 +/- SE 0.03 x 10(9)/l; 7.1 +/- 1.1%) when compared with normal parous controls (0.09 +/- 0.01 x 10(9)/l; 4.2 +/- 0.6%), p less than 0.01 x 10(9)/l; showed significant increases when compared with nulliparous controls (0.04 +/- 0.01 x 10(9)/l; 2.1 +/- 0.2%), p less than 0.01. No differences were detected between the three groups with respect to total T-lymphocytes (CD3), helper T-lymphocytes (CD4), suppressor cytotoxic T-lymphocytes (CD8), or the inducer of suppressor (Leu 3+/Leu 8+) subset of T-lymphocytes. Three women persistently islet cell antibody positive, two of whom were HLA DR4, showed impaired glucose tolerance at the time of lymphocyte subset analysis, while two further patients, one DR3 and the other DR4, had developed type 1 (insulin-dependent) diabetes. No correlation between increased Interleukin 2 receptor expression and glucose intolerance was demonstrated. We conclude that islet cell antibody positive women with impaired glucose tolerance during pregnancy are at increased risk of later developing type 1 diabetes but that heightened immune activation present in these women is in part a post-pregnancy phenomenon.


Asunto(s)
Autoanticuerpos/análisis , Islotes Pancreáticos/inmunología , Periodo Posparto/inmunología , Embarazo en Diabéticas/inmunología , Receptores de Interleucina-2/biosíntesis , Subgrupos de Linfocitos T/inmunología , Adolescente , Adulto , Biomarcadores , Estudios de Cohortes , Diabetes Mellitus Tipo 1 , Femenino , Citometría de Flujo , Prueba de Tolerancia a la Glucosa , Antígenos HLA-DR/análisis , Humanos , Activación de Linfocitos , Persona de Mediana Edad , Embarazo , Receptores de Interleucina-2/análisis , Factores de Riesgo
17.
J Clin Pathol ; 41(5): 558-61, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3290266

RESUMEN

Differential cell counts were performed on 200 paired bone marrow aspirates and trephine biopsy specimens to compare the distribution of cell types. Relatively more immature myeloid cells were found in the trephine biopsy specimens and relatively more polymorphs and lymphocytes in the aspirates. Two methods for sampling areas of the trephine biopsy specimens for counting were assessed, and the differences between aspirates and trephine specimens were found to be more consistent when the second, more extensive, sampling method was used. This method also permitted quantitation of some features of bone marrow topography and provided information that would not normally be obtainable from aspirated material. The techniques were easy to apply and took relatively little time to perform. They could offer useful information in the study of bone marrow disorders, particularly those such as myelodysplastic syndromes in which disturbances of marrow architecture are prominent.


Asunto(s)
Células de la Médula Ósea , Biopsia/métodos , Examen de la Médula Ósea , Recuento de Células , Técnicas Histológicas , Humanos
18.
J Clin Pathol ; 42(3): 271-4, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2467925

RESUMEN

Immunocytochemical studies, using the antibodies CAM 5.2 and NA1/34 (CD1a), were performed on normal lymphoid tissue and malignant lymphomas. A population of dendritic cells in the paracortex of lymph nodes and in T cell lymphomas reacted with both antibodies. Colocalisation with antibodies was also found in gastrointestinal epithelium. Immune blotting shows that the likely basis of this reactivity is a 12 kilodalton peptide which is recognised by both antibodies. This is almost certainly the beta t peptide which has been described as the light chain of CD1a.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Diferenciación/inmunología , Colon/inmunología , Ganglios Linfáticos/inmunología , Estómago/inmunología , Antígenos CD1 , Células Dendríticas/inmunología , Epitelio/inmunología , Epítopos/inmunología , Humanos , Linfoma/inmunología , Linfocitos T
19.
J Clin Pathol ; 41(4): 365-9, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3366919

RESUMEN

Flow cytometry was performed on paraffin embedded tissue from 115 cases of Hodgkin's disease. Thirteen (11%) tumours were aneuploid with no significant difference between the histological subgroups. The median proliferative index was 14%, and the highest values were found in the NS2 (16.4%) and lymphocyte depleted (16.0%) subgroups. The difference in proliferative index approached significance when the NS2 subgroup was compared with the NS1 subgroup (p less than or equal to 0.11) and when the lymphocyte depleted and NS2 subgroups combined were compared with the mixed cellularity, lymphocyte predominance, and NS1 subgroups combined (p less than or equal to 0.07). There was a trend towards better survival for patients with aneuploid tumours and those cases with a proliferative index below 15%, but neither of these trends was significant.


Asunto(s)
ADN de Neoplasias/análisis , Enfermedad de Hodgkin/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Citometría de Flujo , Enfermedad de Hodgkin/análisis , Enfermedad de Hodgkin/mortalidad , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mitosis , Pronóstico
20.
J Clin Pathol ; 56(5): 374-7, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12719459

RESUMEN

AIMS: To evaluate the practicality of use and the effectiveness of a standard protocol for examining nephrectomy specimens for renal cell carcinoma (RCC), with emphasis on the identification of vascular invasion. METHODS: A standard protocol, devised to identify the major prognostic determinants, was used to examine 79 consecutive tumours submitted to four histopathology departments. The incidence of vascular invasion found was compared with the incidence in a historical series of tumours. RESULTS: The protocol proved easy to follow, and appeared to increase the incidence of observed vascular invasion (40 of 69 cases compared with 69 of 176 cases in the historical series; p = 0.059, Fishers exact test, one sided) CONCLUSIONS: If pathological prognostic determinants are to be used for clinical management, then it is important that they are identified and recorded consistently. The protocol described provides a method of examining nephrectomy specimens that can be used in routine practice and would probably reliably identify recognised prognostic variables.


Asunto(s)
Carcinoma de Células Renales/irrigación sanguínea , Neoplasias Renales/irrigación sanguínea , Neovascularización Patológica/patología , Nefrectomía , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Protocolos Clínicos , Disección/métodos , Humanos , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Pronóstico
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