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1.
Public Health ; 168: 26-35, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30682637

RESUMEN

OBJECTIVES: Although presbycusis typically becomes symptomatic only in older age, slight and mild hearing loss may be detectable well before this. We studied current prevalence and characteristics of hearing loss in Australian mid-life adults. STUDY DESIGN: This was a population-derived national cross-sectional study nested within the Longitudinal Study of Australian Children. METHODS: A total of 1485 parents/guardians (87.3% female) aged 30-59 years underwent air-conduction audiometry. Hearing loss was defined in three ways to maximize cross-study comparability: high Fletcher index (mean of 1, 2 and 4 kHz; primary outcome relevant to speech perception), lower frequency (mean of 1 and 2 kHz) and higher frequency (mean of 4 and 8 kHz). Multivariable logistic regression examined how losses vary by age, sex and neighbourhood disadvantage. RESULTS: On high Fletcher index, 27.3% had bilateral and 23.8% unilateral thresholds >15 dB hearing level (HL) (slight or worse), and 4.9% had bilateral and 6.3% unilateral thresholds >25 dB HL (mild or worse). Bilateral higher frequency losses were more common than lower frequency losses for thresholds >15 dB HL (30.9% vs. 26.4%) and >25 dB HL (11.0% vs. 4.6%). Age increased the risk of bilateral speech and higher frequency losses (all P for trend < 0.05), but not lower frequency losses >25 dB HL. Although sex was not associated with speech and lower frequency losses, men were more likely to have bilateral higher frequency losses (e.g. >15 dB HL: odds ratio [OR]: 2.2; 95% confidence interval [CI]: 1.5-3.2, P < 0.001). CONCLUSIONS: Both slight and mild hearing loss show high and rising prevalence across mid-life. This offers opportunities to prevent progression to reduce the profound later burden of age-related hearing loss.


Asunto(s)
Pérdida Auditiva/epidemiología , Adulto , Australia/epidemiología , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Prevalencia , Índice de Severidad de la Enfermedad
2.
Phys Chem Chem Phys ; 18(26): 17461-9, 2016 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-27302145

RESUMEN

The effect of the cooling rate on the solidification process of liquid aluminium is studied using a large-scale molecular dynamics method. It is found that there are various types of short-range order (SRO) structures in the liquid, among which the icosahedral (ICO)-like structures are dominant. These SRO structures are in dynamic fluctuation and transform each other. The effect of the cooling rate on the microstructure is very weak at high temperatures and in supercooled liquids, and it appears only below the liquid-solid transition temperature. Fast cooling rates favour the formation of amorphous structures with ICO-like features, while slow cooling rates favour the formation of FCC crystalline structures. Furthermore, FCC and HCP structures can coexist in crystalline structures. It is also found that nanocrystalline aluminium can be achieved at appropriate cooling rates, and its formation mechanism is thoroughly investigated by tracing the evolution of nanoclusters. The arrangement of FCC and HCP atoms in the nanograins displays various twinned structures as observed using visualization analysis, which is different from the layering or phase separation structures observed in the solidification of Lennard-Jones fluids and some metal liquids.

3.
Bull Entomol Res ; 103(3): 363-71, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23458744

RESUMEN

The guava fruit fly, Bactrocera correcta (Bezzi) (Diptera: Tephritidae), is an invasive pest of fruit and vegetable crops that primarily inhabits Southeast Asia and which has the potential to become a major threat within both the Oriental and Australian oceanic regions as well as California and Florida. In light of the threat posed, it is important to develop a rapid, accurate and reliable method to identify B. correcta in quarantine work in order to provide an early warning to prevent its widespread invasion. In the present study, we describe a species-specific polymerase chain reaction assay for the diagnosis of B. correcta using mitochondrial DNA cytochrome oxidase I (mtDNA COI) barcoding genes. A B. correcta-specific primer pair was designed according to variations in the mtDNA COI barcode sequences among 14 fruit fly species. The specificity and sensitivity of the B. correcta-specific primer pair was tested based on the presence or absence of a band in the gel profile. A pair of species-specific B. correcta primers was successfully designed and named BCOR-F/BCOR-R. An ∼280 bp fragment was amplified from specimens belonging to 17 geographical populations and four life stages of B. correcta, while no such diagnostic bands were present in any of the 14 other related fruit fly species examined. Sensitivity test results demonstrated that successful amplification can be obtained with as little as 1 ng µl⁻¹ of template DNA. The species-specific PCR analysis was able to successfully diagnose B. correcta, even in immature life stages, and from adult body parts. This method proved to be a robust single-step molecular technique for the diagnosis of B. correcta with respect to potential plant quarantine.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Complejo IV de Transporte de Electrones/genética , Marcadores Genéticos/genética , Especies Introducidas , Tephritidae/genética , Distribución Animal , Animales , Asia Sudoriental , Secuencia de Bases , China , Cartilla de ADN/genética , Sistemas de Información Geográfica , Estadios del Ciclo de Vida/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , Sensibilidad y Especificidad , Alineación de Secuencia , Análisis de Secuencia de ADN , Especificidad de la Especie , Tephritidae/crecimiento & desarrollo
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(11): 1109-1114, 2021 Nov 09.
Artículo en Zh | MEDLINE | ID: mdl-34763406

RESUMEN

Objective: To investigate the status quo of human resources of dentists who deal with periodontal disease in Beijing area through an online survey, which may hopefully provide a preliminary basis for the decision-making of administrative departments and the formulation of periodontal professional development plan. Methods: The dentists who deal with periodontal disease at least half a day per week in Beijing area were investigated. A questionnaire was designed by the chairman of the Periodontology Committee of Beijing Stomatological Association. The questionnaire was sent to and finished by the dentists via "WenJuanXing" online survey software. The contents of the survey included general condition, the property of practice unit, title and position of the dentist, membership of professional society, time and content of periodontal treatment, adoption of new technology and new method of periodontal therapy during the past one year, status of periodontal treatment in the local population and reasons, understanding and influencing factors of periodontal professional development. Results: A total of 1 255 dentists completed the survey, who came from all 16 districts in Beijing, mainly Haidian, Chaoyang, Dongcheng and Xicheng Districts [The total percentage of these four main districts was 70.3% (882/1 255)]. The mean age of the dentists was (36.1±8.3) years. Among the dentists, 71.1% (892/1 255) were females, 88.1% (1 106/1 255) got a Bachelor's degree or above. It was estimated that 35.4% (444/1 255) of the dentists had received standardized periodontal training ever. The percentage of dentists carrying out new technology in the past one year was as high as 68.1% (855/1 255). There were only 163 periodontal specialists (13.0%) out of the dentists in the survey. Only 15.9% (200/1 255) of the dentists routinely performed periodontal surgery. The majority of the dentists [82.8% (1 039/1 255)] were from the state-owned hospitals. Fifty-four point seven percemt (686/1 255) of the dentists thought that lack of knowledge was the main reason why the general public failed to receive periodontal treatment. As for the biggest bottleneck affecting periodontal professional development, fifty-one point zero percent (640/1 255) of the dentists attributed it to the public neglect. Conclusions: The periodontal practitioners in Beijing are young, highly educated, unevenly distributed in 16 districts and mostly females. State-owned oral health institutions are an important force in periodontal diagnosis and treatment services in Beijing. The number of periodontal specialists need to be improved. Promotion of standardized periodontal surgery and the popularization of healthcare knowledge on periodontal disease should also be the focus in the future.


Asunto(s)
Enfermedades Periodontales , Adulto , Odontólogos , Femenino , Humanos , Masculino , Enfermedades Periodontales/terapia , Periodoncia , Encuestas y Cuestionarios , Recursos Humanos
5.
Eur Rev Med Pharmacol Sci ; 25(4): 2031-2038, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33660815

RESUMEN

OBJECTIVE: The attention network is the structural basis of cognitive function. As one of the two known attention networks, the ventral attention network (VAN) has a significant impact on the cognitive impairment of patients with epilepsy. Nevertheless, changes in network homogeneity (NH) are rarely reported in the VAN of right temporal lobe epilepsy (rTLE) patients. Therefore, we explored the NH of the VAN in rTLE patients in this study. PATIENTS AND METHODS: Seventy rTLE patients and 69 healthy controls were recruited. All participants underwent resting-state functional magnetic resonance imaging (fMRI), which was the primary method of evaluation. The executive control reaction time (ECRT) was examined via the attentional network test. The Data Processing Assistant for Resting-State fMRI (DPARSF) was used to analyze NH. The independent component analysis (ICA) and correlation analysis were used in data analysis. RESULTS: Compared to the control group, patients with right temporal lobe epilepsy showed a lower NH in the right superior temporal gyrus, and a longer ECRT. However, abnormal NH values had no significant association with the clinical measurements. CONCLUSIONS: Patients with right temporal lobe epilepsy have abnormal NH values in the VAN, and the executive functions in rTLE patients are also altered. The altered NH values in VAN may help provide new insights into the pathophysiology of cognitive impairment in rTLE.


Asunto(s)
Encéfalo/fisiopatología , Disfunción Cognitiva/fisiopatología , Red en Modo Predeterminado/fisiopatología , Epilepsia del Lóbulo Temporal/fisiopatología , Adulto , Femenino , Humanos , Masculino
6.
Nanotechnology ; 21(7): 75102, 2010 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-20090199

RESUMEN

In order to reveal the biocompatibility of Fe(3)O(4) nanoparticles and bipolar surfactant tetramethylammonium 11-aminoundecanoate cytotoxicity tests were performed as a function of concentration from low (0.1 microg ml(-1)) to higher concentration (100 microg ml(-1)) using various human glia, human breast cancer and normal cell lines. Cytotoxicity tests for human glia (D54MG, G9T, SF126, U87, U251, U373), human breast cancer (MB157, SKBR3, T47D) and normal (H184B5F5/M10, WI-38, SVGp12) cell lines exhibited almost nontoxicity and reveal biocompatibility of Fe(3)O(4) nanoparticles in the concentration range of 0.1-10 microg ml(-1), while accountable cytotoxicity can be seen at 100 microg ml(-1). The results of our studies suggest that Fe(3)O(4) nanoparticles coated with bipolar surfactant tetramethylammonium 11-aminoundecanoate are biocompatible and promising for bio-applications such as drug delivery, magnetic resonance imaging and magnetic hyperthermia.


Asunto(s)
Materiales Biocompatibles/farmacología , Neoplasias de la Mama/metabolismo , Mama/efectos de los fármacos , Compuestos Férricos/farmacología , Ensayo de Materiales/métodos , Nanopartículas del Metal/química , Neuroglía/efectos de los fármacos , Aminoácidos/farmacología , Materiales Biocompatibles/química , Mama/citología , Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Compuestos Férricos/química , Humanos , Microscopía , Neuroglía/citología , Neuroglía/metabolismo , Compuestos de Amonio Cuaternario/farmacología , Tensoactivos/farmacología
7.
Neuroimage ; 46(3): 749-61, 2009 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-19236922

RESUMEN

The segmentation from MRI of macroscopically ill-defined and highly variable structures, such as the hippocampus (Hc) and the amygdala (Am), requires the use of specific constraints. Here, we describe and evaluate a fast fully automatic hybrid segmentation that uses knowledge derived from probabilistic atlases and anatomical landmarks, adapted from a semi-automatic method. The algorithm was designed at the outset for application on images from healthy subjects and patients with hippocampal sclerosis. Probabilistic atlases were built from 16 healthy subjects, registered using SPM5. Local mismatch in the atlas registration step was automatically detected and corrected. Quantitative evaluation with respect to manual segmentations was performed on the 16 young subjects, with a leave-one-out strategy, a mixed cohort of 8 controls and 15 patients with epilepsy with variable degrees of hippocampal sclerosis, and 8 healthy subjects acquired on a 3 T scanner. Seven performance indices were computed, among which error on volumes RV and Dice overlap K. The method proved to be fast, robust and accurate. For Hc, results with the new method were: 16 young subjects {RV=5%, K=87%}; mixed cohort {RV=8%, K=84%}; 3 T cohort {RV=9%, K=85%}. Results were better than with atlas-based (thresholded probability map) or semi-automatic segmentations. Atlas mismatch detection and correction proved efficient for the most sclerotic Hc. For Am, results were: 16 young controls {RV=7%, K=85%}; mixed cohort {RV=19%, K=78%}; 3 T cohort {RV=10%, K=77%}. Results were better than with the semi-automatic segmentation, and were also better than atlas-based segmentations for the 16 young subjects.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Inteligencia Artificial , Hipocampo/anatomía & histología , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Adulto , Algoritmos , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Inorg Chem ; 48(24): 11655-9, 2009 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-19919020

RESUMEN

The exposure of (Ti(1-x)Zr(x))Co(2.00) intermetallic alloys to hydrogen at high pressure caused (Ti(1-x)Zr(x))Co(2.00) (x = 0.50-0.90) hydrides in the alloy. The crystalline structural, electronic, and magnetic properties of parent alloys and of their hydrides were determined by using XRD (X-ray powder diffraction) and XAS (X-ray absorption spectrometry) and by the use of SQUID (a superconducting quantum interference device). Hydrogenation did not alter the crystal structure of the parent alloy, but it did increase the volume of the unit cell. An in situ Co K-edge XAS study of the hydride revealed that the valence state of Co increased during discharge (which is the release of hydrogen from the hydride). Hydrogenation of the parent alloy also reduced the magnetic moment. A possible mechanism of discharge for the hydride is also proposed.

9.
Neuroscience ; 155(4): 1221-6, 2008 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-18675887

RESUMEN

Preclinical exploration of pain processing in the brain as well as evaluating pain-relief drugs in small animals embodies the potential biophysical effects in humans. However, it is difficult to measure nociception-related cerebral metabolic changes in vivo, especially in unanesthetized animals. The present study used (18)F-fluorodeoxyglucose small-animal positron emission tomography to produce cerebral metabolic maps associated with formalin-induced nociception. Anesthesia was not applied during the uptake period so as to reduce possible confounding effects on pain processing in the brain. The formalin stimulation at the hind paw of rats resulted in significant metabolic increases in the bilateral cingulate cortex, motor cortex, primary somatosensory cortex, secondary somatosensory cortex, insular cortex, visual cortex, caudate putamen, hippocampus, periaqueductal gray, amygdala, thalamus, and hypothalamus. Among the measured areas, clear lateralization was only evident in the primary somatosensory cortex and hypothalamus. In addition, pretreatment with lidocaine (4 mg/kg, i.v.) and morphine (10 mg/kg, i.v.) significantly suppressed formalin-induced cerebral metabolic increases in these areas. The present protocol allowed identification of the brain areas involved in pain processing, and should be useful in further evaluations of the effects of new drugs and preclinical therapies for pain.


Asunto(s)
Encéfalo/diagnóstico por imagen , Fluorodesoxiglucosa F18/metabolismo , Dolor/diagnóstico por imagen , Tomografía de Emisión de Positrones , Analgésicos/farmacología , Analgésicos/uso terapéutico , Análisis de Varianza , Animales , Encéfalo/efectos de los fármacos , Formaldehído/efectos adversos , Lateralidad Funcional , Lidocaína/farmacología , Lidocaína/uso terapéutico , Masculino , Morfina/farmacología , Morfina/uso terapéutico , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Ratas , Ratas Wistar
10.
J Phys Chem B ; 112(27): 8017-23, 2008 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-18558734

RESUMEN

In this paper, we report the synthesis of carbon coated Li(Mn0.35Co 0.2Fe0.45)PO4 and discuss the effect of Co2P formation during the carbothermal reduction process, which enhances the electrochemical performance of cathode material for lithium ion batteries. It was observed that Co2P was favorably formed in 5% H2/Ar than in Ar atmosphere. The conductivity of Li(Mn0.35Co0.2Fe0.45)PO4/C sintered at 600-800 degrees C in 5% H2/Ar is increased as the temperature is increased. The O K-edge X-ray absorption near edge spectrum (XANES) demonstrates that content of hole carriers is increased in Li(Mn0.35Co0.2Fe0.45)PO4/C as the amount of Co2P increased. We also observed that the capacity of Li(Mn0.35Co0.2Fe0.45)PO4/C is increased with sintering temperature, and it exhibited a maximum capacity of 166 mAh/g at 700 degrees C. It was found that the enhancement in the discharge capacity of sintered Li(Mn0.35Co0.2Fe0.45)PO4/C was as a result of its higher electrical conductivity under 5% H2/Ar atmosphere as compared with Ar atmosphere.

11.
J Phys Chem B ; 112(36): 11250-7, 2008 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-18636763

RESUMEN

In the present investigation, we report the transformation of alpha-LiVOPO 4 to alpha-Li 3V 2(PO 4) 3, leading to an enhancement of capacity. The alpha-LiVOPO 4 sample was synthesized by a sol-gel method, followed by sintering at 550-650 degrees C in a flow of 5% H 2/Ar. The structural transformation of a triclinic alpha-LiVOPO 4 structure to a monoclinic alpha-Li 3V 2(PO 4) 3 structure was observed at higher sintering temperatures (700-800 degrees C in a flow of 5% H 2/Ar). The alpha-Li 3V 2(PO 4) 3 phase was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermal gravimetric analysis, and X-ray absorption near edge spectrum (XANES) techniques. The valence shift of vanadium ions from +4 to +3 states was observed using in situ XANES experiments at V K-edge. The structural transformation is ascertained by the shape changes in pre-edge and near edge area of X-ray absorption spectrum. It was observed that the capacity was enhanced from 140 mAh/g to 164 mAh/g via structural transformation process of LiVOPO 4 to Li 3V 2(PO 4) 3.

12.
J Phys Chem B ; 112(16): 4870-5, 2008 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-18386860

RESUMEN

The synthesis of platinum nanoparticle loaded LiCoO2 (Pt-LiCoO2) was carried out successfully by an impregnation method followed by sintering at different temperatures. The catalytic role of Pt-LiCoO2 composite in hydrogen generation during hydrolysis of sodium borohydride (NaBH4) was studied for fuel cell applications. X-ray diffraction (XRD), transmission electron microscopy (TEM), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) have been used to elucidate the structural and catalytic properties of Pt-LiCoO2. It was found that the 15 wt % of Pt nanoparticles on LiCoO2 sintered at 450 degrees C support showed the maximum efficiency for the catalysis reaction of hydrogen production. X-ray absorption near edge structure (XANES) analysis and extended X-ray absorption fine structure (EXAFS) analysis using a synchrotron radiation source were performed to carry out ex situ measurements in order to understand the mechanism of the catalytic process for the production of hydrogen during the hydrolysis of NaBH4. Co K-edge XANES showed a small percentage of cobalt in the metallic form after hydrogen generation which suggests the reduction of the cobalt during the hydrolysis of NaBH4.

13.
Eur J Gynaecol Oncol ; 29(3): 246-51, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18592788

RESUMEN

PURPOSE OF INVESTIGATION: To assess the clinical use of F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the post-therapy surveillance of uterine sarcoma. METHODS: Eight whole-body FDG-PET studies were performed in seven women with previously treated uterine sarcoma. Conventional image studies (computed tomography) and physical examinations were performed for follow-up. All FDG-PET studies were indicated to localize suspected recurrences noted by conventional methods. RESULTS: The per case sensitivity of the FDG-PET studies and CT scans was 85.7% (6/7) and 100% (7/7), respectively (p = 0.174). FDG-PET was able to detect seven extrapelvic metastastic sites below the diaphragm (7/7, sensitivity: 100%), including the liver, spleen, paraaortic lymph node, spine and paracolic gutter, as well as pulmonary lesions in five patients, while the CT scan detected only three lesions (3/7, sensitivity: 42.9%; p = 0.070). FDG-PET detected only four recurrent pelvic lesions (4/6) and CT scan detected six (6/6) recurrent pelvic lesions (66.7% vs 100%, p = 0.455). CONCLUSIONS: The FDG-PET showed a better detection rate than the abdominal CT scan for extrapelvic metastatic lesions and a similar detection rate as well as abdominal CT scan. FDG-PET can serve as a useful detection tool for patients with uterine sarcomas because nearly 80% of recurrence involve an extrapelvic site.


Asunto(s)
Metástasis de la Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Sarcoma/diagnóstico por imagen , Neoplasias Uterinas/diagnóstico por imagen , Adulto , Anciano , Femenino , Fluorodesoxiglucosa F18 , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Pelvis/diagnóstico por imagen , Pelvis/patología , Radiofármacos , Recurrencia , Sarcoma/patología , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión , Tomografía Computarizada por Rayos X , Neoplasias Uterinas/patología , Imagen de Cuerpo Entero/métodos
14.
J Phys Chem B ; 111(9): 2262-7, 2007 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-17291033

RESUMEN

The effect of isovalent chemical substitution of Eu3+ into the Tb3+ sites on the magnetic and electrical properties of (Tb1-xEux)MnO3 (0

15.
Appl Radiat Isot ; 65(1): 57-63, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16916606

RESUMEN

The aim of this study was to develop an automated synthesis of 9-(4-[(18)F]-fluoro-3-hydroxymethylbutyl)guanine ([(18)F]FHBG) and 9-[(3-[(18)F]fluoro-1-hydroxy-2-propoxy)methyl]guanine ([(18)F]FHPG) using a Scanditronix Anatech RB III robotic system. [(18)F]HF was produced via (18)O(p, n)(18)F using a Scanditronix MC17F cyclotron. On average, a typical run produced [(18)F]FHBG and [(18)F]FHPG with an uncorrected radiochemical yield of 19% and 16%, respectively, at end of synthesis (EOS) from irradiation of 95% enriched [(18)O]water. The total synthesis time was 80 min. The retention time of [(18)F]FHBG and [(18)F]FHPG (the radio-peak) was 3.9 and 4.0 min, respectively, which was consistent with the [(19)F]FHBG and [(19)F]FHPG ultraviolet peak. The radiochemical purity was greater than 97%. A robotic, automated method for [(18)F]FHBG and [(18)F]FHPG radiosynthesis is therefore feasible. The radiation burden for the operator can be reduced as much as possible. Sufficient radioactivities of [(18)F]FHBG and [(18)F]FHPG could be obtained for non-invasive monitoring the expression of transfected gene in vivo with positron emission tomography (PET).


Asunto(s)
Ganciclovir/análogos & derivados , Perfilación de la Expresión Génica/métodos , Guanina/análogos & derivados , Marcaje Isotópico/instrumentación , Tomografía de Emisión de Positrones/métodos , Robótica/instrumentación , Manejo de Especímenes/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Ganciclovir/síntesis química , Ganciclovir/aislamiento & purificación , Perfilación de la Expresión Génica/instrumentación , Guanina/síntesis química , Guanina/aislamiento & purificación , Marcaje Isotópico/métodos , Técnicas de Sonda Molecular , Tomografía de Emisión de Positrones/instrumentación , Radiofármacos/síntesis química , Robótica/métodos , Manejo de Especímenes/métodos
16.
Appl Radiat Isot ; 65(6): 682-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17379530

RESUMEN

This study aimed to develop an automated synthesis of [18F]fluoromisonidazole ([18F]FMISO) using a Scanditronix Anatech RB III robotic system. [18F]HF was produced via the 18O(p,n)18F reaction using a Scanditronix MC17F cyclotron. On average, a typical run produced [18F]FMISO with an uncorrected radiochemical yield of 30+/-5% at end of synthesis (EOS) from the irradiation of 95% enriched [18O]water. The total synthesis time was 65 min. The retention time of [18F]FMISO (the radio-peak) was 4.9 min, which was consistent with the authentic FMISO (the ultraviolet peak). The radiochemical purity was greater than 97%. Preparation of [18F]FMISO using the automated robotic system is highly reliable and reproducible, and the radiation burden for the operator can be largely reduced. Sufficient radioactivities of [18F]FMISO could be obtained for non-invasive tumor hypoxia imaging in vivo with positron emission tomography (PET).


Asunto(s)
Radioisótopos de Flúor/química , Misonidazol/análogos & derivados , Radiofármacos/síntesis química , Hipoxia/diagnóstico por imagen , Misonidazol/síntesis química , Neoplasias/diagnóstico por imagen , Neoplasias/metabolismo , Tomografía de Emisión de Positrones , Robótica
17.
Nuklearmedizin ; 45(5): 201-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17043730

RESUMEN

UNLABELLED: The AIM of this prospective study was to evaluate the usefulness of the thallium-201 ( (201) Tl) thyroid scan in the detection of malignancy in cold thyroid nodules whose status was equivocal following palpation fine-needle aspiration cytology (FNAC). PATIENTS, METHODS: Fifty-one patients with clinically palpable solitary cold thyroid nodules classified as non-diagnostic or suspicious following biopsy underwent (201) Tl thyroid scans. Each scan was performed 15 min (early scan) and 3 h (delayed scan) after an intravenous administration of 74 MBq (201) Tl. Thallium uptake in the nodules was visually assessed and scored on a three point scale, with a grade of three defining malignancy. All patients underwent surgery and the histopathology of nodule tissues were compared with results of the scans. RESULTS: Fifty-one nodules were examined. Forty were benign and 11 were malignant. For early scans, the diagnostically relevant parameters were: sensitivity (100%), specificity (75%), and accuracy (80%). Corresponding findings for the delayed scan were: 91%, 98%, and 96%. CONCLUSION: The (201) Tl scan is useful for detecting malignancy in cold thyroid nodules classified as nondiagnostic or suspicious lesions by FNAC.


Asunto(s)
Radioisótopos de Talio , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Biopsia con Aguja Fina , Femenino , Humanos , Masculino , Cintigrafía , Reproducibilidad de los Resultados
18.
Cancer Res ; 44(8): 3252-7, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6204744

RESUMEN

The antiproliferative effect of human interferons (IFNs) and double-stranded RNAs (dsRNAs) was measured in eight human tumor cell lines, five of which were derived from carcinomas of the bladder. Dose-response curves were generated for a 72-hr treatment period. The concentration of interferon or dsRNA necessary to inhibit tumor cell growth 50% compared to untreated cells was generated by linear regression analysis of the dose-response data. In the seven of eight cell lines in which a direct comparison could be made, IFN-beta was a more potent inhibitor than IFN-alpha. Polyriboinosinic acid X polyribocytidylic acid consistently gave an increased antiproliferative response compared to its mismatched analogue, rln X r(C12,U)n. Correlations could not be made between either IFN-alpha or IFN-beta and the dsRNA effect. No correlation was seen between IFN or dsRNA sensitivity and cell type, ability to bind IFN, growth rate, or tumorigenicity in nude mice. The antiproliferative effect of dsRNA was studied in the presence of antibodies against IFN-beta in HT1080 Cl 4, a cell line sensitive to both IFN and dsRNA, and A2182, a cell line relatively resistant to IFN-beta but sensitive to dsRNA. In both cell lines, the anti-IFN-beta antibodies inhibited the antiproliferative effect of the dsRNAs. After treatment with a concentration of dsRNA necessary to inhibit tumor cell growth 50% compared to untreated cells, a concentration of IFN-beta necessary to inhibit tumor cell growth 50% was induced in the HT1080 Cl 4 cells; however, only a low level of IFN-beta was detected in the culture medium of the A2182 cells.


Asunto(s)
Interferón Tipo I/toxicidad , Interferón gamma/toxicidad , ARN Bicatenario/toxicidad , División Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Interferones/genética , Interferones/metabolismo , Neoplasias/fisiopatología , Receptores de Superficie Celular/metabolismo , Receptores de Interferón
19.
Neurosci Lett ; 375(2): 87-90, 2005 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-15670647

RESUMEN

The present study assesses the changes of dopamine levels in the basal ganglia (BG) of rabbit brain during heatstroke with or without hypothermia therapy. The dopamine levels were determined by using 6(F18) fluoro-L-dopa (FDOPA) positron emission tomography (PET) scan. Heatstroke was induced by exposing the anesthetized rabbits to a high blanket temperature (T(blanket)) of 45 degrees C. Hypothermia therapy was accomplished by decreasing T(blanket) from 45 to 16 degrees C. Regions-of-interest were carefully selected on the BG and cerebellum (C). The uptake ratio of FDOPA was defined as the mean counts per pixel from BG divided by the mean counts from C. BG/C ratios represent the dopamine levels of BG. The results showed that the values of mean arterial pressure (MAP) in heatstroke rabbits without hypothermia therapy were significantly lower than those in normothermic controls. However, BG/C FDOPA ratios were greater. Both the arterial hypotension and the increased BG/C FDOPA ratios observed during heatstroke were all reduced after hypothermia therapy. Our data demonstrate that the dopamine overload visualized in the BG of rabbit brain during heatstroke can be suppressed by hypothermia therapy.


Asunto(s)
Ganglios Basales/diagnóstico por imagen , Ganglios Basales/fisiopatología , Dihidroxifenilalanina/análogos & derivados , Dopamina/metabolismo , Golpe de Calor/diagnóstico por imagen , Golpe de Calor/terapia , Hipotermia Inducida , Animales , Ganglios Basales/metabolismo , Presión Sanguínea , Temperatura Corporal , Cerebelo/diagnóstico por imagen , Cerebelo/metabolismo , Cerebelo/fisiopatología , Dihidroxifenilalanina/farmacocinética , Modelos Animales de Enfermedad , Dopamina/análisis , Golpe de Calor/complicaciones , Hipotensión/etiología , Hipotensión/fisiopatología , Hipotensión/terapia , Masculino , Tomografía de Emisión de Positrones , Conejos
20.
Neurology ; 54(11): 2061-6, 2000 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-10851363

RESUMEN

OBJECTIVE: To examine the effects of estrogen therapy on cognition, mood, and cerebral blood flow in patients with AD. BACKGROUND: Some studies have suggested estrogen may be effective in the treatment of AD. However, most of these studies were not controlled adequately. METHODS: Fifty female AD patients were recruited in a randomized, double-blind, placebo-controlled 12-week trial. Each member of the estrogen-treated group received conjugated estrogen (Premarin) 1.25 mg/day. The primary outcome measures were the Cognitive Ability Screening Instrument (CASI), Clinical Dementia Rating (CDR), and Clinician Interview-Based Impression of Change (CIBIC-plus). The secondary outcome measures were Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD), Hamilton Anxiety Rating Scale (HARS), Hamilton Depression Rating Scale (HDRS), and 99mTc hexamethylpropylene amine oxime SPECT of the brain. RESULTS: No meaningful differences were found between the outcome measures (CASI, CDR, CIBIC-plus, BEHAVE-AD, HARS, HDRS, and cerebral blood flow) taken from the estrogen-treated group and those from the control group. CONCLUSION: A 1.25-mg/day dose of Premarin administered for 12 consecutive weeks does not produce a meaningful effect on cognitive performance, dementia severity, behavior, mood, and cerebral perfusion in female AD patients. Because estrogen therapy has been suspected of yielding adverse effects, and its therapeutic effectiveness is in doubt, additional evaluation of its role in AD treatment ought to be conducted.


Asunto(s)
Afecto/efectos de los fármacos , Enfermedad de Alzheimer/tratamiento farmacológico , Cognición/efectos de los fármacos , Terapia de Reemplazo de Estrógeno , Estrógenos Conjugados (USP)/uso terapéutico , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Distribución de Chi-Cuadrado , Método Doble Ciego , Estrógenos Conjugados (USP)/farmacología , Femenino , Humanos , Persona de Mediana Edad
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