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1.
Cryo Letters ; 41(1): 13-18, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33973979

RESUMEN

BACKGROUND: ATP exogenous (ATPe) has been used successfully in improving motility and fertility for many animal species. However this has not yet been tested on Brycon orbignyamus. OBJECTIVE: The objective of this study was to evaluate the use of ATPe for the cryopreservation of sperm from B. orbignyamus. MATERIALS AND METHODS: The ATPe concentrations tested were 1.0 µM, 5.0 µM and 10 µM combined with Beltsville Thawing SolutionTM extender and dimethylformamide at 7.5%. The sperm were frozen in a nitrogen vapour vessel and stored in liquid nitrogen at -196 ºC. The parameters of viability post-thawing were evaluated using CASA, and flow cytometer. RESULTS: The ATPe did not promote improvements in spermatic kinetics, and in the higher concentrations caused a worsening in these parameters. Also there was loss of mitochondrial functionality and greater cellular disruption with the concentration of 10 µM. CONCLUSION: We do not recommend the addition of ATP for cryopreserving B. orbignyamus.


Asunto(s)
Adenosina Trifosfato , Characiformes , Criopreservación , Crioprotectores , Preservación de Semen , Adenosina Trifosfato/farmacología , Animales , Criopreservación/veterinaria , Crioprotectores/farmacología , Masculino , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides
2.
Opt Express ; 27(5): 7330-7343, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30876298

RESUMEN

Nanoscale plasmonic particles represent a crucial transformation on optical and electronic properties exhibited by advanced materials. Herein are reported remarkable interferometric optical effects with dependence on polarization for filtering or modulating electronic signals in multilayer nanostructures. Metallic nanoparticles were incorporated in randomly distributed networks of reduced graphene oxide by an in-situ vapor-phase deposition method. The polarization-selectable nonlinear optical absorption contribution on the photoconductivity of reduced graphene oxide decorated with gold nanoparticles was analyzed. Nanosecond pulses at 532 nm wavelength were employed in a two-wave mixing experiment to study photoconduction and nonlinear optical absorption in this nanohybrid material. The ablation threshold of the sample was measured in 0.4 J/cm2. Electrochemical impedance spectroscopy measurements revealed a capacitive response that can be enhanced by gold decoration in carbon nanostructures. A strong two-photon absorption process characterized by 5 × 10-7 m/W was identified as a physical mechanism responsible for the nonlinear photoconductive behavior of the nanostructures. Experimental shift of 1 MHz for the cutoff frequency associated with an electrical filter function performed by the sample in film form was demonstrated. Moreover, amplitude modulation of electronic signals controlled by the polarization of a two-wave mixing experiment was proposed. All-optical and optoelectronic nanosystems controlled by multi-photonic interactions in carbon-based materials were discussed. The key role of the vectorial nature of light in two-wave mixing experiments is a fascinating tool for the exploration of low-dimensional systems.

4.
Fish Physiol Biochem ; 43(5): 1237-1244, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28389904

RESUMEN

Cylindrospermopsin (CYN) is a cyanotoxin that is cytotoxic to a wide variety of cells, particularly to the hepatocytes. In this study, the toxic effects of purified CYN were investigated in primary cultured hepatocytes of Neotropical fish Hoplias malabaricus. After isolation, attachment, and recovery for 72 h, the cells were exposed for 72 h to 0, 0.1, 1.0, 10, and 100 µg l-1 of CYN. Then, cell viability and a set of oxidative stress biomarker responses were determined. Catalase, superoxide dismutase, glucose-6-phosphate dehydrogenase, and glutathione S-transferase activities were not affected by exposure to CYN. Concentration-dependent decrease of glutathione reductase activity occurred for most CYN-exposed groups, whereas non-protein thiol content increased only for the highest CYN concentration. Lipid peroxidation, protein carbonylation, and DNA damage levels were not altered, but reactive oxygen species levels increased in the cells exposed to the highest concentration of CYN. Cell viability decreased in all the groups exposed to CYN. Thus, CYN may cause a slight change in redox balance, but it is not the main cause of cell death in H. malabaricus hepatocytes.


Asunto(s)
Toxinas Bacterianas/farmacología , Supervivencia Celular/efectos de los fármacos , Characiformes , Hepatocitos/efectos de los fármacos , Uracilo/análogos & derivados , Alcaloides , Animales , Toxinas Bacterianas/administración & dosificación , Biomarcadores , Células Cultivadas , Toxinas de Cianobacterias , Relación Dosis-Respuesta a Droga , Estrés Oxidativo/efectos de los fármacos , Uracilo/administración & dosificación , Uracilo/farmacología
5.
Radiologia ; 59(3): 253-263, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27671947

RESUMEN

Fever of unknown origin is defined as a body temperature greater than 38.3°C lasting more than three weeks for which the cause could not be found within one week of hospital admission. More than 200 causes have been reported, and these can be classified into four categories: infections, inflammatory diseases, oncologic processes, and miscellaneous conditions. Noninvasive diagnostic techniques are used in 69.2% of cases and invasive techniques in 30.8%. Structural imaging techniques show the morphological changes from infectious, inflammatory, and tumor-related processes, but they do not allow the detection of the early changes brought about by these processes. The metabolic information provided by 18F-FDG PET/CT has a promising role in these patients. 18F-FDG uptake is based on the cells' use of glucose as a source of energy, so it can be observed in infectious, inflammatory, and tumor-related processes. The established non-oncologic indications for 18F-FDG PET/CT are sarcoidosis, osteomyelitis, spondylodiscitis, fever of unknown origin, and vasculitis, which together account for more than 85% of studies.


Asunto(s)
Fiebre de Origen Desconocido/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Infecciones/diagnóstico por imagen , Inflamación/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Fiebre de Origen Desconocido/etiología , Humanos , Infecciones/complicaciones , Inflamación/complicaciones
6.
Q J Nucl Med Mol Imaging ; 59(3): 342-50, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24844254

RESUMEN

AIM: Aim of the present study was to evaluate the usefulness of 11C-choline PET/CT for detecting lymphatic or haematogenous spread and for planning radiotherapy in patients with medium-to-high risk prostate cancer. METHODS: We have included 61 consecutive patients recently diagnosed with cancer prostate by biopsy. All patients were classified as medium-to-high risk: Gleason: 7-9; PSA: 6.3-30.4 ng/mL; stage T2c (N.=20) or stage T3 (N.=41). Image acquisition began 5 min after intravenous injection of 11C-choline (656+119 MBq), starting at the pelvis and continuing craniocaudally. Images were interpreted visually to evaluate uptake by the prostate gland. Lymph nodes with 11C-choline uptake were considered invaded, regardless of their size. Bone lesions were considered positive when they showed greater focal uptake than the surrounding bone. In patients with evidence of lymph-node invasion or bone metastases (15 patients), disease was classified as locoregional, oligometastatic, or multimetastatic. RESULTS: All patients had prostate gland uptake (20 focal, 8 bifocal, and 33 multifocal). Extraprostatic disease was present in 15 patients (24.6%), as follows: 9 (60%) in a single location: in an infradiaphragmatic lymph node (N.=6), in a supradiaphragmatic lymph node (N.=1), and in bone (M1) (N.=2). Six (40%) as multifocal invasion: with both infra- and supradiaphragmatic lymph node involvement (N.=2); with infradiaphragmatic lymph node involvement and M1 bone metastases (N.=3); and infra- and supradiaphragmatic lymph node involvement plus M1 bone metastases (N.=1). Disease was classified as locoregional (N.=6), oligometastatic (N.=5), and multimetastatic (N.=4). The 11 (73.3%) patients with locoregional and oligometastatic disease were selected to undergo intensity-modulated radiation therapy with dose escalation based on the PET findings. CONCLUSION: Our results suggest that 11C-choline PET/CT is a useful one-stop diagnostic procedure for evaluating patients with medium/high risk prostate cancer scheduled for radical treatment. 11C-choline PET/CT can reliably rule out lymph node involvement and remote metastases, allowing to select candidates for radiotherapy and to plan their treatment.


Asunto(s)
Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Radiofármacos/química , Planificación de la Radioterapia Asistida por Computador , Anciano , Biopsia , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Radioisótopos de Carbono/química , Colina/química , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Tomografía de Emisión de Positrones , Estudios Prospectivos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X
7.
Radiologia ; 57(6): 489-95, 2015.
Artículo en Español | MEDLINE | ID: mdl-25857249

RESUMEN

OBJECTIVE: To review the findings on (18)F-FDG PET-CT in patients with fever of unknown origin lasting more than 7 days. MATERIAL AND METHODS: This retrospective descriptive observational study included 93 (18)F-FDG PET-CT studies to detect a fever-causing focus done at three nuclear medicine centers from October 2006 through February 2014. A nuclear medicine specialist and a radiologist reviewed the images for foci of pathological uptake; another specialist's opinion resolved discrepancies. The findings on (18)F-FDG PET-CT studies were checked against clinical and/or histological findings. RESULTS: Abnormal (18)F-FDG uptake on PET-CT that could explain the cause of the fever was found in 52 (56%) of the 93 studies, and the cause of the fever was confirmed in 50 of these 52 studies. In the 50 cases in which the cause of the fever was confirmed, infection was the most common cause (54%), followed by noninfectious inflammatory disease (28%) and tumors (18%). CONCLUSION: (18)F-FDG PET-CT is useful in diagnosing the cause of prolonged febrile illness, so it might be practical to use it earlier in the diagnostic process.


Asunto(s)
Fiebre/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Humanos , Radiofármacos , Estudios Retrospectivos
8.
Mol Ecol ; 23(6): 1333-1347, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24384031

RESUMEN

Many organisms have intimate associations with beneficial microbes acquired from the environment. These host-symbiont associations can be specific and stable, but they are prone to lower partner specificity and more partner-switching than vertically transmitted mutualisms. To investigate partner specificity in an environmentally acquired insect symbiosis, we used 16S rRNA gene and multilocus sequencing to survey the bacterial population in the bacteria-harbouring organ (crypts) of 49 individuals across four sympatric broad-headed bug species (Alydus calcaratus, A. conspersus, A. tomentosus and Megalotomus quinquespinosus). Similar to other insect-bacteria associations, Burkholderia spp. were the most common residents of the crypts in all four insect species (77.2% of recovered sequences). Burkholderia presence was associated with prolonged survival to adulthood in A. tomentosus, suggesting a beneficial role of these specialized associations. Burkholderia were also found in environmental reservoirs in the insects' habitat, which may facilitate acquisition by insects by increasing Burkholderia-insect encounters. Symbiont establishment could also be facilitated by resistance to insect defences; zone of inhibition assays demonstrated that Burkholderia and other bacteria isolated from crypts are resistant to insect defences that limit growth of Escherichia coli. Alternatively, the insects' defences may not efficiently kill a broad range of bacteria. Although the symbiosis is targeted to Burkholderia, the insects' crypts housed other bacteria, including non-Burkholderiaceae species. There is no significant effect of host insect species on Burkholderia distribution, suggesting a lack of strong partner specificity at finer scales. The presence of frequent partner-switching between sympatric insects and their symbionts likely prevents tight co-evolutionary dynamics.


Asunto(s)
Burkholderia/clasificación , Heterópteros/microbiología , Simbiosis , Simpatría , Animales , Técnicas de Tipificación Bacteriana , Burkholderia/genética , Burkholderia/aislamiento & purificación , ADN Bacteriano/genética , Sistema Digestivo/microbiología , Ecosistema , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Filogenia , ARN Ribosómico 16S/genética , Microbiología del Suelo
9.
Artículo en Inglés | MEDLINE | ID: mdl-37865228

RESUMEN

OBJECTIVE: To evaluate the detection rate and therapeutic implication of the infiltration of the internal mammary chain (IMCI) by [18F]FDG PET/MRI for staging of patients with breast cancer. METHODS: Prospective study including 41 women with breast cancer (stage ≥ IIB) staged by [18F]FDG PET/MR. Two-phase exam: breast imaging (prone), whole-body (supine). TNM stage assessed by peer consensus with Nuclear Medicine and Radiology specialists. Study of the afferent vessel (AV) to IMC by breast MRI. IMCI was correlated with age, AV-IMC, T stage, breast quadrants, axillary and distant infiltration. Therapeutic re-evaluation by a multidisciplinary committee. RESULTS: IMCI detection rate of 34% (14/41), with 8/14 patients under 55 years of age. All 14 patients with IMCI showed AV-IMC, 6 of them (43.9%) without VA-axillary. Of 27/41 patients without IMCI, in 13 (48.1%) only AV-axillary was found, in the remaining 14 (51.9%), AV-axillary and AV-IMC was found. In 57% (8/14) tumours were multicentric and 42% (6/14) focal, in inner quadrants in 4/6 (66.7%). In 1/14 patient (7.1%) only IMCI was found, in 9/14 (64.3%) axillary and IMC, in 4/14 patients (28.6%) distant lesions were detected. Committee re-evaluation: no further treatment in 27/41 patients (65.8%), thoracic radiotherapy in 10/41 patients (24.4%), systemic therapy in 4/41 patients (9.7%). CONCLUSION: Our detection rate of IMCI in breast cancer staging by [18F]FDG PET/MR was 34%. Related factors were age, multicentric tumours, inner quadrants, detection of AV-IMC, NM staging. The evidence of IMCI allowed tailored therapy, with thoracic radiotherapy implementation in 24.4% of patients.


Asunto(s)
Neoplasias de la Mama , Fluorodesoxiglucosa F18 , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/terapia , Neoplasias de la Mama/patología , Estudios Prospectivos , Radiofármacos , Estadificación de Neoplasias , Imagen por Resonancia Magnética
10.
Artículo en Inglés | MEDLINE | ID: mdl-39009305

RESUMEN

OBJECTIVE: To analyse the efficacy of integrated assessment of [18F]F-PSMA-1007 PET/MRI on the early detection of local recurrence (LR) for prostate cancer patients with PSA levels <0.5ng/ml after radical prostatectomy. To assess the location of recurrence so that therapy may be tailored to patient. METHODS: Prospective study including 35 patients with prostate cancer (PCa), who were referred for a [18F]F-PSMA-1007 PET/MR after prostatectomy with a very initial PSA value increase (PSA<0,5ng/ml). Simultaneous acquisition in a PET/MRI hybrid equipment (SIGNA-GE), 1h after administration of 370%±10% MBq of [18F]F-PSMA-1007: Prostate selective imaging (20min): multiparametric PET+MRI (MRImp): DIXON, T1, T2, diffusion sequences post-gadolinium administration. Whole body image (30min): PET+MRI: DIXON, T1, T2, diffusion, STIR sequences. A nuclear physician and a radiologist jointly reviewed the studies: In order to assess LR, the "Prostate Imaging for Recurrence Reporting" system was used on MRI, as well as the Likert scale on the PET prostate imaging. The remaining lesions were classified as N1 and M1a. RESULTS: PET/MRI was positive in 25 patients (71,4%) and negative in 10 patients (28,6%). RL was detected in 15 patients (42.9%): in 2 (5.7%) MRI was superior; in 3 (8.6%) PET was superior; integrated PET/MRI showed improved results in 5 patients (14.3%) for the detection of LR. Location of recurrences: LR in 11 patients (44.0%); N1 in 10 (40.0%); LR+N1 (8.0%) in 2; LR+N1+M1a in 2 (8.0%). In 20 patients (80%) the PET/MRI findings allowed radioguided radiotherapy implementation (11 on LR, and 9 on N1), whereas hormonal treatment was decided in 5 patients (20%) due to multimetastases/spread disease. CONCLUSION: [18F]F-PSMA-1007 PET/MRI has a 71.4% recurrence detection rate after prostatectomy with PSA<0.5ng/ml. Its combined PET and MRI study increases the detection of LR by 14.3%, with a high N1+M1a detection rate (56%), allowing radioguided radiotherapy in 80% of patients.

11.
Semergen ; 50(1): 102076, 2024.
Artículo en Español | MEDLINE | ID: mdl-37837727

RESUMEN

BACKGROUND: Peritonsillar infection (PTI) is a reason for urgent consultation due to intense throat discomfort. A delayed or inaccurate diagnosis can jeopardize the upper aerodigestive tract and be fatal in its evolution. Our objective was to develop a predictive model for the presence of IPA helping in its rapid detection. PATIENTS AND METHODS: A 66-month retrospective observational study from 2017 was carried out in a county and tertiary referral hospitals, registering data from all patients diagnosed with PTI and a proportional volume of subjects with pharyngeal symptoms without PTI. Collection of clinical, exploratory and demographic data among participants. Their higher relative risk of PTI presence allowed them to be considered as variables to be tested. Development of a scoring scale for the probability of suffering from it and logistic regression analysis, obtaining the ROC curve with the best diagnostic correlation. Internal validation and estimation of the predictive values of the model. RESULTS: On 348 cases of PTI, the assessment scale scored the presence of six variables: trismus (3), unilateral dysphagia-odynophagia (2), velar bulging (2), reflex otalgia (1), pharyngolalia (1) and age between 16 and 46 years (1). With a range of 0-10, a cut-off ≥6 offered a sensitivity of 96.1%, a specificity of 93.9%, and an efficiency of 94.9%. The area under the ROC curve was 0.979. CONCLUSIONS: The internal validation of this model based on signs and symptoms makes it a very useful tool for early detection of PTI in otorhinolaryngology and primary care.


Asunto(s)
Trastornos de Deglución , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Riesgo , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/etiología , Derivación y Consulta
14.
Appl Opt ; 52(22): E22-7, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23913083

RESUMEN

Electrical and nonlinear optical experiments were performed on multiwall carbon nanotubes (CNTs) prepared by a chemical vapor deposition method. We report that the incorporation of platinum particles on the CNTs surface originates an enhancement in the photoconductive properties with noticeable capabilities to modulate optical and electrical signals. The photoconductive logic gate function OR was experimentally demonstrated using a simple photoconductive platform based on our samples. A two-photon absorption effect was identified as the main mechanism of third-order optical nonlinearity under a nonresonant nanosecond excitation. Multiphotonic interactions were described in order to explain the observed behavior.

15.
Appl Radiat Isot ; 195: 110742, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36857814

RESUMEN

Two samples, one of natural iridium and the other of enriched 193Ir, were irradiated with a monoenergetic neutron beam of energy 6.0 MeV at the Triangle Universities Nuclear Laboratory. The product of the 193Ir [Formula: see text] Ir reaction was determined by means of measuring X-rays following electron conversion of the isomeric state at 80.2 keV in 193Ir. The cross section for inelastic neutron scattering is reported disagreeing with the literature data.

16.
Neurologia (Engl Ed) ; 37(6): 434-440, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34092536

RESUMEN

INTRODUCTION: Stroke affects around 15 million people per year, with 10%-15% occurring in individuals under 50 years old (stroke in young adults). The prevalence of different vascular risk factors and healthcare strategies for stroke management vary worldwide, making the epidemiology and specific characteristics of stroke in each region an important area of research. This study aimed to determine the prevalence of different vascular risk factors and the aetiology and characteristics of ischaemic stroke in young adults in the autonomous community of Aragon, Spain. METHODS: A cross-sectional, multi-centre study was conducted by the neurology departments of all hospitals in the Aragonese Health Service. We identified all patients aged between 18 and 50 years who were admitted to any of these hospitals with a diagnosis of ischaemic stroke or TIA between January 2005 and December 2015. Data were collected on demographic variables, vascular risk factors, and type of stroke, among other variables. RESULTS: During the study period, 786 patients between 18 and 50 years old were admitted with a diagnosis of ischaemic stroke or TIA to any hospital of Aragon, at a mean annual rate of 12.3 per 100 000 population. The median age was 45 years (IQR: 40-48 years). The most prevalent vascular risk factor was tobacco use, in 404 patients (51.4%). The majority of strokes were of undetermined cause (36.2%), followed by other causes (26.5%). The median NIHSS score was 3.5 (IQR: 2.0-7.0). In total, 211 patients (26.8%) presented TIA. Fifty-nine per cent of the patients admitted with a diagnosis of ischaemic stroke (10.3%) were treated with fibrinolysis. CONCLUSIONS: Ischaemic stroke in young adults is not uncommon in Aragon, and is of undetermined aetiology in a considerable number of cases; it is therefore necessary to implement measures to improve study of the condition, to reduce its incidence, and to prevent its recurrence.


Asunto(s)
Isquemia Encefálica , Ataque Isquémico Transitorio , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Adolescente , Adulto , Isquemia Encefálica/complicaciones , Isquemia Encefálica/epidemiología , Estudios Transversales , Humanos , Ataque Isquémico Transitorio/complicaciones , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/terapia , Adulto Joven
17.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33579662

RESUMEN

AIM: Evaluate the therapy impact of initial staging in patients diagnosed with prostate cancer by 18 F-choline PET/MRI hybrid technique. MATERIAL: A prospective study which included 31 patients diagnosed with prostate cancer; Gleason > 7; mean PSA 13.6 ng/mL (range 6.3-20.6). PET/MRI studies were acquired simultaneously with hybrid equipment (SIGNA.3T, GE) following intravenous injection of 185 ± 18.5MBq of 18F-choline: - Early/prostate imaging: PET emission + multiparametric MR: DIXON-T1-T2-diffusion-gadolinium. - Late/whole-body imaging: PET emission + MR: DIXON-T1-T2-diffusion-STIR sequences. Images were visually evaluated. SUV & ADC & textures were also calculated. Treatment selection was based upon Oncology Committee consensus decision. RESULTS: Procedure was well tolerated in all patients, and no artifacts were reported. MRI was superior in T staging in eight patients (25.8%) (Likert: 2-3), whereas PET increased MRI sensitivity in three patients (9.7%) (PIRADS: 3). PROSTATE LESION LOCATION: Peripheral 91.4%, transitional 8.6%. SUVmax threshold: 2.95: sensitivity 92.9%, specificity 66.7%. No correlation SUV vs. ADC. Better distinction between stage T2 vs. T3 using the DiscrLin model with NG = 16 (AUC 0.7767 ± 0.3386). PET was superior to T2 in textures analysis (0.588 vs. 0.412). Seventeen patients (54.8%) were staged ≥ T3, with surgical treatment being contraindicated. Fifteen patients (48.4%) presented with extra-prostatic disease: 8/31 oligometastatic and 7/31 multiple metastasis. Therapy approach following PET/MRI was: radical treatment in 24/31 patients (77.4%), 14 radical prostatectomy and 10 MRI-guided radiotherapy; systemic treatment in 7/31 patients (22.6%). CONCLUSION: 18F-choline PET/MRI had a complementary role for the T staging, with a high detection rate for NM infiltration. PET/MRI findings allowed patients to be directed either to prostatectomy or MRI-guided radiotherapy, and thus avoiding radicaltreatment in 22.6% of patients.

18.
Rev Esp Med Nucl ; 29(6): 285-8, 2010.
Artículo en Español | MEDLINE | ID: mdl-20702003

RESUMEN

AIM: To determine the impact of an additional inspiration CT scan on the conventional ¹8F-FDG PET-CT protocol in the detection of small pulmonary nodules. METHOD: One hundred consecutive patients who presented with one or various nodules were studied. Whole-body PET-CT was performed using Gemini (Philips). CT acquisition parameters were 120 kV/25 mAs, the same as those for the transmission/fusion CT (mild expiration) and inspiratory CT. RESULTS: A total of 188 nodules were detected in the inspiratory CT with sizes between 0.3-3 cm. Non-inspiratory CT did not show 20/188 nodules (10.6%) with sizes between 0.3-1cm, this corresponding to 17 patients. The most frequent localization of non-detectable nodules in non-inspiratory CT was the lower lobes. ¹8F-FDG uptake was detected by the PET in 83.9% and 72% of nodules with > 1 cm and between 0.7 and 1cm, respectively. However, only 10.5% of nodules <0.7 cm showed increased metabolic activity. CONCLUSION: In selected patients, inspiratory CT added to conventional PET-CT significantly improves the detection of small nodules (10.6%), especially in those lesions located in the lower lobes, due to respiratory movements, and may have an impact on patient management.


Asunto(s)
Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Radiofármacos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Artefactos , Carcinoma/diagnóstico por imagen , Carcinoma/secundario , Reacciones Falso Negativas , Femenino , Humanos , Inhalación , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Movimiento , Estudios Prospectivos , Cintigrafía , Sensibilidad y Especificidad , Nódulo Pulmonar Solitario/diagnóstico por imagen
19.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32192907

RESUMEN

AIM: To standardize acquisition protocols for 18F-Choline PET/CT to prevent from urine interference, to determine the best time point for the whole-body study, and to assess whether "dual point" acquisition allows for differentiating malignant vs. benign lesions. METHODS: One hundred consecutive patients with prostate cancer were prospectively studied. Immediately after 18F-Choline injection, a pelvis study was acquired, and a whole-body was subsequently obtained 1 and 2 hours p.i. Mean SUVmax was obtained in regions and for every sequential imaging. Mean analysis (χ2) and SUV percentage change (2/1 hours; 1 hours/0 min) were obtained. Metabolic pattern dynamics were assessed: accumulative vs. clearance. Patient follow-up after therapy and directed classification whenever ethically possible were performed. RESULTS: Fifty-three prostate foci, without disturbing urinary activity was ever found on early images. Accumulative pattern in 42, with percentage increase was: 0 min/1 hour: +16.7% (χ20.94); 1/2 hours: +10,0% (χ2 0.83). Clearance pattern in 11, with percentage decrease: 0 min/1 hour: -21.4% (χ20.91): -7.7% (χ20.85), corresponding in 7 to initial staging and in 4 post-radiotherapy biochemical recurrence. Every infradiaphragmatic uptake (n: 24) showed accumulative pattern, with percentage increase of +9.1% (χ20.97), all of them depicted on early imaging. As for 12 supradiaphragmantic uptake, 8 of them showed clearance pattern with percentage decrease: -13.0% (χ20.95). Accumulative pattern showed in 4 of them with percentage increase +13.0% (χ2 0.96), thus being assessed as invasive/malignant. Every bone uptake (n: 18) showed accumulative pattern, with percentage increase: +17.1% (χ20.95), all of them depicted on 1 hour imaging. CONCLUSIONS: As for prostate assessment is concerned, dual point at 0 min/1 hour proved to be the best procedure. As for supradiaphragmatic lymph-nodes detection, dual point with 1/2 hours performed best. As for infradiaphragmatic and bone involvement, as well as for inconclusive findings, the 2 hour imaging increased our diagnostic confidence.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Colina/análogos & derivados , Radioisótopos de Flúor , Tomografía Computarizada por Tomografía de Emisión de Positrones/normas , Neoplasias de la Próstata/diagnóstico por imagen , Radiofármacos , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Colina/farmacocinética , Colina/orina , Diagnóstico Diferencial , Radioisótopos de Flúor/farmacocinética , Radioisótopos de Flúor/orina , Humanos , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Pelvis/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Estudios Prospectivos , Enfermedades de la Próstata/diagnóstico por imagen , Radiofármacos/farmacocinética , Radiofármacos/orina , Factores de Tiempo , Imagen de Cuerpo Entero
20.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32165153

RESUMEN

OBJECTIVE: To assess the detection rate of 18F-Choline PET/MRI and subsequent changes in therapy approach for patients with prostate cancer treated by prostatectomy and with rising levels of PSA <1 ng/ml. METHODS: Prospective study with our first 36 patients with prostatectomy for prostate cancer and rising levels of PSA, who were referred for an 18F-Choline PET/MRI study. A dual-phase study was acquired after intravenous administration of 185±10% MBq of 18F-Choline: 1) early imaging (immediately after tracer administration) of prostate area (emission PET/Multiparametric MRI). 2) whole-body imaging 1 h after tracer injection (emission PET/MRI: T1, T2, STIR, diffusion). The therapy approach for patients was decided upon the Oncology Committee consensus based on 18F-Choline PET/MRI findings. RESULTS: Twenty out of 36 patients (55.6%) were positive for the 18F-Choline PET/MRI study: 8 (22.2%) within the prostatectomy bed, 7 (19.4%) with infradiaphragmatic lymph nodes, 4 (11.1%) with local recurrence and infradiaphragmatic lymph nodes, and 1 (2.8%) with bone metastasis. Sixteen out of the 36 patients (44.4%) were negative for the 18F-Choline PET/MRI study. 18F-Choline PET/MRI findings had an impact on the therapy approach to follow: 15 patients (41.6%) showed oligometastatic disease which was treated by imaging-guided radiotherapy, 5 (13.9%) with multiple metastatic disease were treated by androgen deprivation therapy, 16 (44.4%) negative were under active surveillance. CONCLUSION: Hybrid 18F-Choline PET/MRI procedure showed a high detection rate for recurrence in prostate cancer patients treated with prostatectomy and rising PSA levels <1 ng/ml, and 18F-Choline PET/MRI findings resulted in a better tailored therapy approach delivered to our patients.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Colina/análogos & derivados , Radioisótopos de Flúor , Calicreínas/sangre , Imagen Multimodal , Imágenes de Resonancia Magnética Multiparamétrica/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico por imagen , Radiofármacos , Adenocarcinoma/sangre , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Anciano , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Manejo de la Enfermedad , Reacciones Falso Negativas , Reacciones Falso Positivas , Humanos , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Estudios Prospectivos , Prostatectomía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/cirugía , Terapia Recuperativa
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