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1.
J Neurosurg Sci ; 58(2): 87-94, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24819485

RESUMEN

AIM: Even if endovascular techniques are improving, treatment of complex intracranial aneurysms still remains a neurosurgeon challenge. Adenosine administration, producing a brief and profound systemic hypotension, seems to improve surgical aneurysm visualization facilitating its exclusion with less risks of rupture. In our retrospective study we confirmed that adenosine advantages could be determinant for an optimal surgical result. METHODS: We retrospectively reviewed all unruptured complex cerebral aneurysms surgically treated in our institution between August 2009 and April 2012. Treatment of those aneurysms was surgical, with proximal temporary artery occlusion or adenosine induced flow arrest. We compared the two different techniques, evaluating intra- and postoperative data; a three-month follow-up including a neurological assessment, cerebral angiography and echocardiography for the adenosine group was performed. RESULTS: Twenty-four patients were collected in our study. Eleven patients underwent traditional temporary proximal clipping while in 13 patients intraoperative adenosine was used. Most common location was paraclinoid region. We did not observe any complication in the adenosine group. Adenosine was well tolerated, spontaneous recovery of sinusal cardiac rhythm was observed even at high and subsequent doses. The Intensive Care Unit and Hospital length of stay were shorter in adenosine group. A three-month follow-up did not show cardiac abnormalities with good angiographic aneurysms exclusion. CONCLUSION: We observed that adenosine administration allowed an easier clipping thanks to a reduced wall tension in a clearer surgical field without cardiological adverse events. In our opinion adenosine induced arrest technique could be an efficacious, harmless and reliable alternative strategy for surgical treatment of complex cerebral aneurysms.


Asunto(s)
Adenosina/administración & dosificación , Aneurisma Roto/prevención & control , Circulación Cerebrovascular/efectos de los fármacos , Aneurisma Intracraneal/tratamiento farmacológico , Aneurisma Intracraneal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Adenosina/efectos adversos , Adulto , Anciano , Anestesia/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/efectos adversos , Procedimientos Neuroquirúrgicos/instrumentación , Estudios Retrospectivos , Instrumentos Quirúrgicos , Resultado del Tratamiento , Vasodilatadores/administración & dosificación , Vasodilatadores/efectos adversos
2.
Child Care Health Dev ; 39(3): 442-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22676178

RESUMEN

BACKGROUND: Children living with juvenile idiopathic arthritis (JIA) have swollen, painful and stiff joints, which may have an impact on all spheres of their life, as well as their family. While children diagnosed in their preschool years may be at risk for worse physical outcomes than children diagnosed later in life, it is not clear whether they have worse psychological outcomes and whether these outcomes have an impact on their everyday life. The aim of this study was to examine the association between age at diagnosis and health outcomes in families of children with JIA. METHODS: Parents of children with JIA (n = 182) who attended rheumatology clinics at the Montreal Children's Hospital and British Columbia Children's Hospital completed measures assessing socio-demographic attributes, their child's health status, health-related quality of life and pain level, as well as their own level of psychological distress and coping behaviours. Regression models explored the association between age at diagnosis and health outcomes while adjusting for sex, age, severity and duration of the disease. RESULTS: Parents of children diagnosed with JIA before 5 years of age found their child to have a better health-related quality of life in terms of psychosocial functioning than parents of children diagnosed later [ß = -0.91 (-1.63, -0.19)]. Children diagnosed younger were also found to be less limited in schoolwork or activities with friends because of emotional or behavioural problems than children diagnosed later [odds ratio = 0.07 (0.01, 0.42)]. CONCLUSIONS: Children diagnosed younger seem to show good psychosocial adjustment, which may also be true for their caregivers. Perhaps more attention to psychosocial adjustment should be given to families of children who are diagnosed with the disease at an older age.


Asunto(s)
Artritis Juvenil/diagnóstico , Adaptación Psicológica , Adolescente , Factores de Edad , Artritis Juvenil/psicología , Artritis Juvenil/rehabilitación , Cuidadores/psicología , Niño , Preescolar , Diagnóstico Precoz , Salud de la Familia , Estado de Salud , Humanos , Dolor/etiología , Dimensión del Dolor/métodos , Padres/psicología , Calidad de Vida , Estrés Psicológico/etiología
3.
Diabetologia ; 55(3): 579-88, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22234648

RESUMEN

AIMS/HYPOTHESIS: A positive impact of exercise intervention programmes on quality of life (QoL) may be important for long-term patient compliance to exercise recommendations. We have previously shown that QoL improves significantly with supervised exercise, whereas it worsens with counselling alone, in patients with type 2 diabetes from the Italian Diabetes and Exercise Study (IDES). Here, we report data on the relationship between changes in QoL and volume of physical activity/exercise in these individuals. METHODS: This multicentre parallel randomised controlled, open-label, trial enrolled sedentary patients with type 2 diabetes (n = 606 of 691 eligible) in 22 outpatient diabetes clinics. Patients were randomised by centre, age and diabetes treatment using a permuted-block design to twice-a-week supervised aerobic and resistance training plus exercise counselling (exercise group) versus counselling alone (control group) for 12 months. Health-related QoL was assessed by the 36-Item Short Form (SF-36) Health Survey. RESULTS: In the exercise group (n = 268 of 303 randomised), there was a trend for increasing QoL with increasing exercise volume, with significant improvement of the physical component summary (PCS) measure only above 17.5 metabolic equivalents h⁻¹ week⁻¹ and a clear volume-relationship for the mental component summary (MCS) measure. A relationship with volume of physical activity also was observed in the control group (n = 260 of 303 randomised), despite overall deterioration of all scores. Independent correlates of improvements in both PCS and MCS were exercise volume, study arm and, inversely, baseline score. CONCLUSIONS/INTERPRETATION: This large trial shows a relationship between changes in physical and mental health-related QoL measures and volume of physical activity/exercise, with supervised exercise training also providing volume-independent benefits.


Asunto(s)
Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/terapia , Ejercicio Físico/psicología , Centros de Acondicionamiento/métodos , Calidad de Vida , Índice de Masa Corporal , Estudios de Cohortes , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/análisis , Humanos , Italia , Estilo de Vida , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Escalas de Valoración Psiquiátrica , Entrenamiento de Fuerza , Conducta Sedentaria , Encuestas y Cuestionarios
4.
Artículo en Inglés | MEDLINE | ID: mdl-24785317

RESUMEN

In 2008, after the crisis of buffalo dairy fields in Campania, Italy, an assessment of the contamination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) was also necessary for other animal species bred in the region. The contents of PCDDs, polychlorinated dibenzofurans (PCDFs), and dl-PCBs were determined by high-resolution gas chromatography/mass spectrometry (HR-GC/MS) (according to USEPA method 1613) in 69 sheep and goat milk samples from 63 farms. In eleven samples from six sheep farms, the PCDD/Fs levels exceeded the maximum limit of 3.0 pg g(-1) fat established by the European Commission, in particular the concentrations ranged between 3.89 and 12.90 pg g(-1) fat. Statistical treatment of the results for the congener profiles of the non-compliant and compliant samples has been used to identify the sources of contamination.


Asunto(s)
Contaminación de Alimentos/análisis , Cabras , Leche/química , Bifenilos Policlorados/análisis , Ovinos , Animales , Benzofuranos/análisis , Búfalos , Dibenzofuranos Policlorados , Dioxinas , Cromatografía de Gases y Espectrometría de Masas/métodos , Italia , Concentración Máxima Admisible , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análisis
5.
Nutr Metab Cardiovasc Dis ; 20(8): 608-17, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19695853

RESUMEN

BACKGROUND AND AIMS: We investigated the effect of different exercise modalities on high sensitivity-C reactive protein (hs-CRP) and other inflammatory markers in patients with type 2 diabetes and the metabolic syndrome. METHODS AND RESULTS: Eighty-two patients were randomized into 4 groups: sedentary control (A); receiving counseling to perform low-intensity physical activity (B); performing prescribed and supervised high-intensity aerobic (C) or aerobic+resistance (D) exercise (with the same caloric expenditure) for 12 months. Evaluation of leisure-time physical activity and assessment of physical fitness, cardiovascular risk factors and inflammatory biomarkers was performed at baseline and every 3 months. Volume of physical activity increased and HbA(1c) decreased in Groups B-D. VO(2max), HOMA-IR index, HDL-cholesterol, waist circumference and albuminuria improved in Groups C and D, whereas strength and flexibility improved only in Group D. Levels of hs-CRP decreased in all three exercising groups, but the reduction was significant only in Groups C and D, and particularly in Group D. Changes in VO(2max) and the exercise modalities were strong predictors of hs-CRP reduction, independent of body weight. Leptin, resistin and interleukin-6 decreased, whereas adiponectin increased in Groups C and D. Interleukin-1ß, tumor necrosis factor-α and interferon-γ decreased, whereas anti-inflammatory interleukin-4 and 10 increased only in Group D. CONCLUSION: Physical exercise in type 2 diabetic patients with the metabolic syndrome is associated with a significant reduction of hs-CRP and other inflammatory and insulin resistance biomarkers, independent of weight loss. Long-term high-intensity (preferably mixed) training, in addition to daytime physical activity, is required to obtain a significant anti-inflammatory effect.


Asunto(s)
Proteína C-Reactiva/análisis , Diabetes Mellitus Tipo 2/inmunología , Ejercicio Físico , Inflamación/prevención & control , Síndrome Metabólico/inmunología , Pérdida de Peso , Adulto , Anciano , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Humanos , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Factor de Necrosis Tumoral alfa/sangre
6.
Chemosphere ; 77(9): 1212-6, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19836049

RESUMEN

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and certain dioxin-like polychlorinated biphenyls (dl-PCBs) are a family of chemically-related lipophilic compounds characterized by similar toxicity. Due to their properties they are universally distributed in the environment and classified as persistent organic pollutants (POPs). From most of studies carried out to evaluate human dietary intake, milk and dairy products result as a major contributors of PCDD/Fs uptake. Of course the main source of milk contamination is animal feeds. Lactating ruminants, cows included, transfer these compounds to the food chain by ingestion of contaminated vegetables or soil. Their resistance to degradation and a high lipophilicity means that PCDD/Fs and dl-PCBs may be accumulated into fat tissues from which they are transferred to milk during lactation period. Seventy-nine cows milk samples, collected in the monitoring plan 2008, were analyzed for PCDD/Fs and dl-PCBs. Eleven milk samples were non-compliant corresponding to five breeding livestock located in Caserta province. The distribution of PCDD/Fs and dl-PCBs congeners in these samples was examined in order to determine the likely sources of dioxins. The results show that the congener profile is characterized by a prevalence of PCDFs in respect of PCDDs, that represents the typical pattern of thermal origin contamination.


Asunto(s)
Benzofuranos/análisis , Dioxinas/análisis , Contaminantes Ambientales/análisis , Leche/química , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análogos & derivados , Animales , Dibenzofuranos Policlorados , Monitoreo del Ambiente/métodos , Italia , Dibenzodioxinas Policloradas/análisis
7.
Child Care Health Dev ; 35(1): 33-40, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19523000

RESUMEN

OBJECTIVES: The objectives of this study are: (1) to describe parental coping in a cohort of children with physical disabilities (PDs); (2) to determine whether the child's level of function is associated with parental coping; and (3) to explore whether socio-demographic factors such as child's age, maternal education and family structure are associated with parental coping. METHODS: Parents of 150 children with PDs were interviewed after being referred to community rehabilitation services. They answered the following: the Coping Health Inventory for Parents, the Functional Independence Measure for children (WeeFIM) and a study questionnaire that addressed socio-demographic characteristics. Multiple linear regression models were used to determine the association between level of function and other factors and parental coping. RESULTS: Mean (SD) age of the children was 40.9 (15.2) months and 64.7% were male. Parental coping scores, measured by the Coping Health Inventory for Parents, indicated that the parents in our study found seeking out social support from community resources useful. Parents of children with moderate to severe dysfunction in mobility (WeeFIM) found coping behaviours related to communicating with the healthcare professionals regarding their child's condition useful (beta coefficient, 2.07; 95% CI, 0.37, 3.78). Greater perceived usefulness of maintaining social support through community resources was associated with lower maternal education, working parents and two-parent families. CONCLUSION: These findings underscore the importance of helping parents of children with PDs maintain social support. It is important to help parents understand their child's medical situation, especially those whose children have more severe mobility dysfunction.


Asunto(s)
Adaptación Psicológica , Personas con Discapacidad/rehabilitación , Familia/psicología , Padres/psicología , Actividades Cotidianas , Niño , Preescolar , Evaluación de la Discapacidad , Escolaridad , Femenino , Humanos , Lactante , Masculino , Padres/educación , Relaciones Profesional-Familia , Análisis de Regresión , Autocuidado , Factores Socioeconómicos
9.
Eur J Biochem ; 267(18): 5733-41, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10971584

RESUMEN

The stability of the dodecameric Listeria innocua ferritin at low pH values has been investigated by spectroscopic methods and size-exclusion chromatography. The dodecamer is extremely stable in comparison to the classic ferritin tetracosamer and preserves its quaternary assembly at pH 2.0, despite an altered tertiary structure. Below pH 2.0, dissociation into dimers occurs and is paralleled by the complete loss of tertiary structure and a significant decrease in secondary structure elements. Dissociation of dimers into monomers occurs only at pH 1.0. Addition of NaCl to the protein at pH 2.0 induces structural changes similar to those observed upon increasing the proton concentration, although dissociation proceeds only to the dimer stage. Addition of sulfate at pH values >/= 1.5 prevents the dissociation of the dodecamer. The role played by hydrophilic and hydrophobic interactions in determining the resistance to dissociation of L. innocua ferritin at low pH is discussed in the light of its three-dimensional structure.


Asunto(s)
Ferritinas/química , Listeria/química , Aniones , Cromatografía , Dicroismo Circular , Dimerización , Electroforesis en Gel de Poliacrilamida , Ferritinas/metabolismo , Concentración de Iones de Hidrógeno , Hierro/metabolismo , Modelos Moleculares , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Cloruro de Sodio/farmacología , Espectrometría de Fluorescencia , Sulfatos/metabolismo , Sulfatos/farmacología , Rayos Ultravioleta
10.
Biochem J ; 338 ( Pt 1): 71-5, 1999 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-9931300

RESUMEN

The polypeptide chain that assembles into the unusual dodecameric shell of Listeria innocua apoferritin lacks the ferroxidase centre characteristic of H-type mammalian chains, but is able to catalyse both Fe(II) oxidation and nucleation of the iron core. A cluster of five carboxylate residues, which correspond in part to the site of iron core nucleation typical of L-type mammalian ferritins, has been proposed to be involved in both functions. The features of the iron uptake kinetics and of Fe(II) autoxidation in the presence of citrate followed spectrophotometrically confirm this assignment. In Listeria the kinetics of iron uptake is hyperbolic at low Fe(II)-to-dodecamer ratios and becomes sigmoidal when iron exceeds 150 Fe(II) atoms per dodecamer, namely when a fast crystal growth phase follows a slow initial nucleation step. Iron autoxidation in the presence of citrate displays a similar behaviour. Thus the time course is sigmoidal at low citrate-to-Fe ratios at which Fe(III) polymerization is predominant, but is hyperbolic at ligand concentrations high enough to prevent polymerization. The marked inhibitory effect of Tb(III) on the kinetics of iron incorporation confirms that carboxylates provide the iron ligands in L. innocua apoferritin. Iron uptake followed in steady-state fluorescence experiments allows one to distinguish Fe(II) binding and oxidation from the subsequent movement of Fe(III) into the apoferritin cavity as in mammalian ferritins despite the different localization of the tryptophan residues.


Asunto(s)
Ferritinas/metabolismo , Hierro/metabolismo , Listeria/metabolismo , Apoferritinas/química , Catálisis , Citratos/química , Ferritinas/química , Concentración de Iones de Hidrógeno , Hierro/química , Cinética , Oxidación-Reducción , Citrato de Sodio , Espectrometría de Fluorescencia , Terbio/química , Zinc/química
11.
Clin Cancer Res ; 4(11): 2585-9, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9829720

RESUMEN

Head and neck squamous cell carcinomas (SCCs) seem to follow a multistep process of carcinogenesis in which chemical and/or viral agents are associated with specific genetic alterations. The prevalence of human papillomavirus (HPV) infection and the amplification of the cyclin D1 (CCND1) gene were evaluated in a series of 75 laryngeal SCCs by PCR with HPV consensus primers and Southern blot analysis with a CCND1-specific probe, respectively. HPV DNA was detected in 22 of 75 (29.3%) tumors, and it belonged almost exclusively to the highly oncogenic HPV-16, HPV-18, and HPV-33. CCND1 gene amplification was found in 15 of 75 (20%) tumors, and it was associated with HPV infection in a statistically significant manner (chi2 = 20.3; P < 0.001). Because the viral oncoproteins E6 and E7 from high-risk HPV types are known to promote genomic rearrangements, these findings suggest that amplification of the CCND1 gene in laryngeal SCCs may occur as a consequence of the genomic instability associated with HPV infection. In turn, amplified CCND1, either alone or in conjunction with a direct action of the viral oncoproteins E6 and E7, could lead to a perturbation of the cell cycle. This model could explain the involvement of high-risk HPV types in laryngeal carcinogenesis.


Asunto(s)
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virología , Ciclina D1/genética , Amplificación de Genes , Neoplasias Laríngeas/complicaciones , Papillomaviridae , Infecciones por Papillomavirus/complicaciones , Infecciones Tumorales por Virus/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , ADN Viral/análisis , Femenino , Humanos , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/virología , Masculino , Persona de Mediana Edad , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Infecciones Tumorales por Virus/virología
12.
Protein Sci ; 7(2): 427-32, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9521120

RESUMEN

Iron oxidation and incorporation into apoferritins of different subunit composition, namely the recombinant H and L homopolymers and the natural horse spleen heteropolymer (10-15% H), have been followed by steady-state and time-resolved fluorescence. After aerobic addition of 100 Fe(II) atoms/polymer, markedly different kinetic profiles are observed. In the rL-homopolymer a slow monotonic fluorescence quenching is observed which reflects binding, slow oxidation at the threefold apoferritin channels, and diffusion into the protein cavity. In the rH-homopolymer a fast fluorescence quenching is followed by a partial, slow recovery. The two processes have been attributed to Fe(II) binding and oxidation at the ferroxidase centers and to Fe(III) released into the cavity, respectively. The fluorescence kinetics of horse spleen apoferritin is dominated by the H chain contribution and resembles that of the H homopolymer. It brings out clearly that the rate of the overall process is limited by the rate at which Fe(III) leaves the ferroxidase centers of the H chains where binding of incoming Fe(II) and its oxidation take place. The data obtained upon stepwise addition of iron and the results of optical absorption measurements confirm this picture. The correspondence between steady-state and time-resolved data is remarkably good; this is manifest when the latter are used to calculate the change in fluorescence intensity as apparent in the steady-state measurements.


Asunto(s)
Ferritinas/biosíntesis , Bazo/metabolismo , Animales , Biopolímeros , Ferritinas/química , Ferritinas/metabolismo , Caballos , Humanos , Cinética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectrometría de Fluorescencia
13.
Haematologica ; 82(3): 262-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9234570

RESUMEN

BACKGROUND AND OBJECTIVE: Telomerase is the enzyme that stabilizes and elongates the telomeric ends of chromosomes. It is expressed in germline and malignant cells and absent in most human somatic cells. The selective expression of telomerase has thus been proposed to be a basis for the immortality of germline and malignant cells. Recently, telomerase activity has been observed in human bone marrow (BM) and peripheral blood (PB) samples. The objective of our study was to further characterize the telomerase-expressing population in BM and PB. METHODS: CD34+ cells were isolated from BM and PB, cultured in vitro, and telomerase activity was assessed by the PCR-based TRAP assay. RESULTS: Telomerase activity in human BM and PB could be almost exclusively assigned to the hematopoietic progenitor cell fraction expressing the CD34 antigen. We observed telomerase activity in CD34+ cells from BM and cytokine-mobilized PB. CD34+ cells lacking co-expression of CD33 demonstrated higher levels of telomerase than myeloid committed CD34+/CD33+ cells. In vitro culture of CD34+ cells in the presence of a cocktail of growth factors inducing differentiation resulted in a decrease of telomerase activity. Telomerase activity increased in peripheral blood during cytokine-induced mobilization of hematopoietic progenitor cells. INTERPRETATION AND CONCLUSIONS: Our data demonstrate that at least a portion of the hematopoietic stem/progenitor cell fraction expresses telomerase and downregulates its expression through differentiation.


Asunto(s)
Células Madre Hematopoyéticas/enzimología , Telomerasa/análisis , Antígenos CD34/análisis , Células Sanguíneas/enzimología , Células de la Médula Ósea , Diferenciación Celular , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Inducción Enzimática , Factores de Crecimiento de Célula Hematopoyética/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Linfoma/patología , Linfoma de Células B Grandes Difuso/enzimología , Linfoma de Células B Grandes Difuso/patología , Células Madre Neoplásicas/enzimología , Reacción en Cadena de la Polimerasa , Células Tumorales Cultivadas
14.
Clin Cancer Res ; 2(11): 1895-900, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9816146

RESUMEN

The activation of telomerase has been shown to be an important step during tumorigenesis in a variety of malignancies and is associated with characteristics of cellular immortality, such as indefinite proliferative potential. We studied telomerase activity in a series of human laryngeal carcinomas. Thirty-six tumors from 35 patients were studied using a sensitive PCR-based technique, the telomeric repeat amplification protocol assay. Telomerase activity was present in 32 tumors (89%), and the level of activity correlated with the stage of disease. In two of four telomerase-negative tumors, we found evidence of an inhibitor of telomerase activity. In many cases, samples of mucosa surrounding the tumor were also studied, and telomerase could be detected in 16 of 21 patients. For this reason, we proceeded to perform a topographical analysis that demonstrated a pattern of telomerase activity suggestive of a spread of telomerase-positive cells. In conclusion, these data indicate that telomerase activation is important for laryngeal carcinogenesis and that telomerase assay might be a valuable addition to determine the spread of the disease.


Asunto(s)
Carcinoma de Células Escamosas/enzimología , Neoplasias Laríngeas/enzimología , Telomerasa/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/secundario , Inhibidores Enzimáticos/metabolismo , Humanos , Mucosa Laríngea/enzimología , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patología , Estadificación de Neoplasias , Estadística como Asunto , Telomerasa/antagonistas & inhibidores , Células U937
15.
Arch Biochem Biophys ; 325(1): 58-64, 1996 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-8554343

RESUMEN

The thermal stability of horse spleen apoferritin, a heteropolymer composed of 90% L and 10% H chains, has been studied by differential scanning calorimetry and compared with that of the human recombinant H homopolymer. The denaturation temperatures (Tm) are significantly higher for the horse spleen polymer than for the recombinant protein under all experimental conditions (e.g., at pH 7, Tm values are > or = 93 and 77 degrees C, respectively). The thermal denaturation process displays substantial reversibility for both polymers up to a few degrees below Tm, as indicated by CD measurements in the far and near uv regions. At temperatures higher than Tm the thermograms are influenced by the exothermic contribution of aggregation and/or precipitation. The H homopolymer thermogram, which is not distorted by the exotherm, is consistent with a multistate denaturation process. Acid dissociation of apoferritin produces stable dimeric subunits. The thermal unfolding of both dimeric subunits is reversible at least up to Tm and is characterized by an inversion of stability relative to the polymers (at pH 3.5, Tm is 42 degrees C for the horse spleen and 50 degrees C for the H subunit). These results indicate that the stabilization of the polymeric structure arises mainly from interactions between dimers, in accordance with the crystallographic evidence that the dimers are the building blocks of the polymeric molecule.


Asunto(s)
Apoferritinas/química , Calor , Bazo/química , Animales , Rastreo Diferencial de Calorimetría , Estabilidad de Medicamentos , Caballos , Humanos , Concentración de Iones de Hidrógeno , Sustancias Macromoleculares , Proteínas Recombinantes/química , Termodinámica
16.
Clin Cancer Res ; 2(1): 175-80, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9816104

RESUMEN

The cyclin D1 (CCND1) gene is amplified, rearranged, and overexpressed frequently in human cancer, including squamous cell carcinoma. The gene dosage of CCND1 was examined in 51 primary laryngeal squamous cell carcinomas, and amplification of the gene was found in 9 (17.6%) cases. CCND1 amplification did not correlate with age, tumor localization and extension, cervical lymph node involvement, histopathological grading, and epidermal growth factor receptor levels. In a univariate analysis, CCND1 amplification, tumor extension, lymph node involvement, poor histological differentiation, and high epidermal growth factor receptor levels were correlated significantly with shorter overall survival. In a median follow-up period of 29 months, the overall survival rate was 71.4% for patients affected with tumors displaying a normal CCND1 dosage and only 25.0% for patients affected with tumors carrying amplified CCND1 (P = 0.0288). In a multivariate analysis, only CCND1 and tumor extension retained statistically significant prognostic values (P = 0.037 and 0.041, respectively). This is the first report in which CCND1 amplification is identified as a significant independent prognostic factor in laryngeal carcinoma. Evaluation of CCND1 amplification could be applicable to the clinical management of laryngeal cancer, allowing identification of patients with poor prognoses.


Asunto(s)
Carcinoma de Células Escamosas/genética , Ciclina D1/genética , Amplificación de Genes , Neoplasias Laríngeas/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Receptores ErbB/análisis , Femenino , Humanos , Neoplasias Laríngeas/mortalidad , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia
17.
J Inorg Biochem ; 44(1): 27-37, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1791467

RESUMEN

The interaction of hydroxypyridinones with human serum transferrin and ovotransferrin has been studied by analyzing the distribution of iron between the chelator and the proteins as a function of both ligand concentration and transferrin saturation. The kinetics of iron removal by 3-hydroxypyridin-4-ones from both transferrins is slow; in ovotransferrin it appears to be monophasic, in contrast to that observed for serum transferrin. After 24 hours incubation at a 40:1 chelator:protein molar ratio, the percentage of iron removed from Fe(III)-ovotransferrin is 50%-60%, and is somewhat higher in the case of serum transferrin, in line with the respective affinity constants for the metal. The 3-hydroxypyridin-2-ones and the 3-hydroxypyran-4-ones, both of which have lower affinities for Fe(III), remove smaller proportions of the metal. The percentage of desaturation obtained with bidentate and hexadentate pyridinones appears to be similar for both transferrin classes at chelator:protein molar ratios from 40:1. The degree of transferrin saturation influences the extent of chelator mediated iron mobilization in the case of serum transferrin, but not of ovotransferrin. 59Fe competition studies demonstrate that bidentate pyridin-4-ones are capable of donating iron to serum apotransferrin; the relative concentrations of ligand and protein influence the distribution of iron because their effective binding constants (at pH 7.4) for Fe(III) are similar.


Asunto(s)
Quelantes/farmacología , Conalbúmina/metabolismo , Hierro/metabolismo , Piridonas/farmacología , Transferrina/metabolismo , Apoproteínas/metabolismo , Humanos , Radioisótopos de Hierro , Cinética , Relación Estructura-Actividad
18.
Magn Reson Med ; 11(3): 283-7, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2550718

RESUMEN

A murine anti-human melanoma monoclonal antibody fragment was labeled with gadolinium and its proton relaxation efficiency compared to controls at frequencies ranging from 2 to 300 MHz. Relaxation time variations were about 30-40% in 10-15 microM solutions. The labeled fragment showed proton relaxation enhancement relative to free gadolinium, while preserving its immunoreactivity. A tentative labeling of a melanoma pellet by means of the fragment, just at the borderline of a minimum expected T1 variation, gave no detectable difference.


Asunto(s)
Anticuerpos Monoclonales/análisis , Anticuerpos Antineoplásicos/análisis , Espectroscopía de Resonancia Magnética , Melanoma/inmunología , Animales , Sitios de Unión de Anticuerpos , Gadolinio , Humanos , Fragmentos Fab de Inmunoglobulinas , Ratones , Protones , Factores de Tiempo
20.
J Speech Hear Res ; 28(1): 79-87, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3982000

RESUMEN

The timing of prephonatory movements of the larynx, rib cage, and abdomen was examined in order to gain insight into the contribution of the vocal folds to the posturing of the chest wall. A simple stimulus-response paradigm was used in eliciting brief utterances--/a/ and /ha/--from six adult males. Chest wall movements were observed using mercury strain gages while simultaneous electroglottographic and airflow records provided information about vocal fold behavior. Independence of prephonatory laryngeal and chest wall behavior was demonstrated. Laryngeal adjustment preceded the start of vocal fold oscillation by a constant amount of time, whereas the time of onset of the chest wall adjustment varied as a function of the utterance type. The qualitative characteristics of prephonatory chest wall posturing were unaffected by altering glottal configuration requirements. Rib cage enlargement occurred during postural adjustment while the vocal folds were abducted (in preparation for /h/). This implies that rib cage enlargement during prephonatory chest wall posturing was not a passive response to abdominal compression.


Asunto(s)
Laringe/fisiología , Habla/fisiología , Tórax/fisiología , Adulto , Glotis/fisiología , Humanos , Masculino , Fonación , Costillas/fisiología , Factores de Tiempo
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