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1.
J Hand Surg Am ; 48(9): 955.e1-955.e8, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35550311

RESUMEN

PURPOSE: Proximal row carpectomy (PRC) can be performed in the late stages of Kienböck disease using the traditional open technique or arthroscopically. In this study, we describe the arthroscopically-assisted mini-open PRC technique. The aim of the study was to compare the functional results with the open PRC technique in advanced-stage Kienböck disease. METHODS: The medical records of patients with Kienböck disease who underwent open PRC between 2006-2010 (Cohort A) and arthroscopically-assisted PRC (AAPRC) between 2010-2018 (Cohort B) were analyzed. The Quick Disabilities of the Arm, Shoulder, and Hand scores, visual analog scale, and Modified Mayo Wrist Scores were compared, which were obtained at the early postoperative (third month) and final follow-up. RESULTS: Cohort A had 14 and Cohort B 21 patients. The preoperative, early, and final mean visual analog scale scores were 7, 3, and 0.3, respectively, for Cohort A, and 7, 0.3, and 0.1, respectively, for Cohort B. The preoperative mean Quick Disabilities of the Arm, Shoulder, and Hand scores decreased from 69 to 34 at the third-month and 6.1 on the final follow-up visit for Cohort A and from 77 to 18, and 5 for Cohort B. The final Mayo wrist scores were excellent in 4, good in 4, and moderate in 6 of the Cohort A patients, and excellent in 11, good in 8, and moderate in 2 of the Cohort B patients. Mean flexion increased to 52° from 43° for Cohort A and to 62° from 41° for Cohort B. CONCLUSIONS: AAPRC, compared to the open PRC, resulted in increased wrist motion and increased Mayo wrist scores in the long-term. Also, the third-month patient-related outcomes revealed favorable results in the AAPRC group. We attribute these findings to the earlier initiation of postoperative wrist motion and the less invasive character of the AAPRC procedure. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Huesos del Carpo , Osteonecrosis , Humanos , Huesos del Carpo/cirugía , Articulación de la Muñeca/cirugía , Muñeca , Osteonecrosis/cirugía , Rango del Movimiento Articular , Estudios de Seguimiento
2.
J Am Coll Radiol ; 19(5S): S194-S207, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35550802

RESUMEN

The staging and surveillance of testicular cancer is a complex topic, which integrates clinical, biochemical, and imaging components. The use of imaging for staging and surveillance of testicular cancer is individually tailored to each patient by considering tumor histology and prognosis. This document discusses the rationale for use of imaging by imaging modality during the initial staging of testicular seminoma and nonseminoma tumors and during the planned surveillance of stage IA and IB testicular cancer by histological subtype integrating clinical suspicion for disease recurrence in surveillance protocols. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Asunto(s)
Neoplasias Testiculares , Diagnóstico por Imagen , Medicina Basada en la Evidencia , Humanos , Masculino , Neoplasias de Células Germinales y Embrionarias , Sociedades Médicas , Neoplasias Testiculares/diagnóstico por imagen , Estados Unidos
3.
Environ Sci Pollut Res Int ; 29(13): 19731-19740, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34718969

RESUMEN

The present paper discussed the comparison of the persistence and mobility of metsulfuron-methyl from a residue field trial experiment and simulation using a VARLEACH model. The residue field trial experiment was performed at Sungai Buloh Oil Palm Estate, Selangor. The plots were treated with metsulfuron-methyl at two treatment rates of 15 g a.i ha-1 (T1) and 30 g a.i ha-1 (T2). Soil samples were collected at 0, 1, 3, 7, 14, 21, 30, 60 and 90 days after treatment (DAT) and analysed subsequently by HPLC-UV. The results show that metsulfuron-methyl degraded rapidly in the soil with the half-life (t½) of 6.3 days in T1 and 7.9 days in T2. The simulation of VARLEACH model gave similar pattern of persistence and mobility of metsulfuron-methyl in the soil profile. However, total residues and the mobility of the metsulfuron-methyl were poorly simulated by the VARLEACH model due to consistent overestimation of the quantified residues. Results indicated that the metsulfuron-methyl lost more rapidly than the prediction values from VARLEACH model. In this case, simulation models which use transformation routines similar and which include additional degraded processes such as leaching, volatilisation, plant uptake or runoff could be considered. Albeit, overestimated values on the concentrations of metsulfuron-methyl are reported using VARLEACH model, the model still can be used as rapid and fast approach to predict the behaviour of pesticide at minimum cost.


Asunto(s)
Herbicidas , Contaminantes del Suelo , Arilsulfonatos , Herbicidas/química , Suelo/química , Contaminantes del Suelo/análisis
4.
Tech Hand Up Extrem Surg ; 26(1): 63-68, 2021 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-34265840

RESUMEN

The treatment choice in scapholunate (SL) injury depends on the extent of the SL ligament tear, chronicity of injury, quality of the ligament remnants, reducibility of carpal malalignment, and cartilage status of the radiocarpal and midcarpal joints. In the absence of degenerative changes with chronic reducible dissociation, the optimal treatment would be the reconstruction of the SL interosseous ligament. Various SL reconstruction techniques via open or arthroscopic approaches have been described over the years; they include tendon reconstructions, volar/dorsal capsulodesis, SL allografts, bone-tissue-bone composite grafts, reduction and association of the scaphoid and lunate procedure, SL axis method, and SL internal brace technique. However, all of these techniques have their own shortcomings and disadvantages. The present study demonstrates a new technique using a suture-button device for the reduction and fixation of SL diastasis. The suture-button system is positioned between the scaphoid and the triquetrum, the direction of the system prevents scaphoid flexion and maintains continuity of the reduction. Arthroscopic dorsal ligamento-capsulodesis technique can be added to achieve biological healing during the stabilization process. The major advantages of this technique over others are a straightforward application with shorter operative time and lack of a need for harvesting a tendon graft. The technique is performed through mini-incisions, which enable a shorter postoperative recovery time and rehabilitation period and a quicker restoration of function which decreases the risk of joint stiffness. Furthermore, large bone tunnels which increase the risk of fracture are avoided.


Asunto(s)
Inestabilidad de la Articulación , Hueso Semilunar , Hueso Escafoides , Humanos , Inestabilidad de la Articulación/cirugía , Ligamentos Articulares/lesiones , Ligamentos Articulares/cirugía , Hueso Semilunar/cirugía , Hueso Escafoides/cirugía , Suturas , Articulación de la Muñeca/cirugía
5.
J Am Coll Radiol ; 18(5S): S126-S138, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33958107

RESUMEN

Urothelial cancer is the second most common cancer, and cause of cancer death, related to the genitourinary tract. The goals of surveillance imaging after the treatment of urothelial cancer of the urinary bladder are to detect new or previously undetected urothelial tumors, to identify metastatic disease, and to evaluate for complications of therapy. For surveillance, patients can be stratified into one of three groups: 1) nonmuscle invasive bladder cancer with no symptoms or additional risk factors; 2) nonmuscle invasive bladder cancer with symptoms or additional risk factors; and 3) muscle invasive bladder cancer. This document is a review of the current literature for urothelial cancer and resulting recommendations for surveillance imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Asunto(s)
Carcinoma de Células Transicionales , Radiología , Neoplasias de la Vejiga Urinaria , Medicina Basada en la Evidencia , Humanos , Sociedades Médicas , Estados Unidos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen
6.
J Am Coll Radiol ; 17(11S): S487-S496, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33153559

RESUMEN

Urinary tract infections (UTIs) in women are common, with an overall lifetime risk over >50%. UTIs are considered recurrent when they follow complete clinical resolution of a previous UTI and are usually defined as at least three episodes of infection within the preceding 12 months. An uncomplicated UTI is classified as a UTI without structural or functional abnormalities of the urinary tract and without relevant comorbidities. Complicated UTIs are those occurring in patients with underlying structural or medical problems. In women with recurrent uncomplicated UTIs, cystoscopy and imaging are not routinely used. In women suspected of having a recurrent complicated UTI, cystoscopy and imaging should be considered. CT urography or MR urography are usually appropriate for the evaluation of recurrent complicated lower urinary tract infections or for women who are nonresponders to conventional therapy, develop frequent reinfections or relapses, or have known underlying risk factors. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Asunto(s)
Sociedades Médicas , Infecciones Urinarias , Medicina Basada en la Evidencia , Femenino , Humanos , Imagen por Resonancia Magnética , Estados Unidos , Infecciones Urinarias/diagnóstico por imagen
7.
Biomolecules ; 10(7)2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32708824

RESUMEN

A field trial experiment was conducted to investigate the degradation of metsulfuron-methyl at two application dosages, 15 g a.i/ha and 30 g a.i/ha, at an oil palm plantation. Soil samples were collected at ‒1, 0, 1, 3, 7, 14, and 21 days after treatment (DAT) at the following depths: 0-10, 10-20, 20-30, 30-40, and 40-50 cm. The results showed rapid degradation of metsulfuron-methyl in the soil, with calculated half-life (t½) values ranging from 6.3 and 7.9 days. The rates of degradation of metsulfuron-methyl followed first-order reaction kinetics (R2 = 0.91-0.92). At the spray dosage of 15 g a.i/ha, metsulfuron-methyl residue was detected at up to 20-30 cm soil depth, at 3.56% to 1.78% at 3 and 7 DAT, respectively. Doubling the dosage to 30 g a.i/ha increased the metsulfuron-methyl residue in up to 30-40 cm soil depth at 3, 7, and 14 DAT, with concentrations ranging from 1.90% to 1.74%. These findings suggest that metsulfuron-methyl has a low impact on the accumulation of the residues in the soil at application dosages of 15 g a.i/ha and 30 g a.i/ha, due to rapid degradation, and the half-life was found to be 6.3 to 7.9 days.


Asunto(s)
Arilsulfonatos/análisis , Herbicidas/análisis , Contaminantes del Suelo/análisis , Arecaceae/crecimiento & desarrollo , Producción de Cultivos , Cinética , Aceite de Palma/química , Suelo/química
8.
Cureus ; 12(1): e6574, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-32051792

RESUMEN

Introduction Adrenal incidentalomas (AI) are adrenal masses that are discovered during radiological examinations conducted for other reasons. In this study, we focused on the pathological and radiological properties of nonfunctional AI(NFAI) and the association with malignancy risk in our clinical series. Methods A total of 186 patients underwent adrenalectomy between 2010 and 2017; of these, 76 (40.8%) patients with non-functional AI were included in the current study. The radiological and pathologic characteristics of these AIs were retrospectively analyzed to determine the malignancy rate. Results There were 22 (28.9%) male and 54 (71.1%) female patients with nonfunctional AI included in this study. The median age was 55 (range: 24-85) years. Of the patients included, 37 (48.6%) had AI on the left and 39 (51.3%) had AI on the right adrenal gland. Sixty-one (80.2%) cases were treated laparoscopically, four (5.3%) required conversion to open surgery due to intraoperative difficulties such as bleeding and adhesions, and 11 (14.4%) were managed with open adrenalectomy. The rate of malignancy in the tumors with diameters of <4 cm, 4-6 cm, and >6 cm was found to be 0%, 2.9%, and 13.6%, respectively. Conclusions Determining the ideal cutoff value for surgical indication in an NFAI is challenging. Besides the malignancy risk, the rate of silent pheochromacytomas must be taken into account in the surgical decision.

9.
J Am Coll Radiol ; 16(11S): S378-S383, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31685105

RESUMEN

Lower urinary tract symptoms due to benign prostatic enlargement have a high prevalence in men over 50 years of age. Diagnosis is made with a combination of focused history and physician examination and validated symptom questionnaires. Urodynamic studies can help to differentiate storage from voiding abnormalities. Pelvic ultrasound may be indicated to assess bladder volume and wall thickness. Other imaging modalities, including prostate MRI, are usually not indicated in the initial workup and evaluation of uncomplicated lower urinary tract symptoms from an enlarged prostate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Asunto(s)
Síntomas del Sistema Urinario Inferior/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/diagnóstico por imagen , Radiología/normas , Urodinámica/fisiología , Anciano , Medicina Basada en la Evidencia , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Síntomas del Sistema Urinario Inferior/patología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Control de Calidad , Sociedades Médicas/normas , Ultrasonografía Doppler/métodos , Estados Unidos
10.
J Am Coll Radiol ; 16(11S): S392-S398, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31685107

RESUMEN

Lower urinary tract injury is most commonly the result of blunt trauma but can also result from penetrating or iatrogenic trauma. Clinical findings in patients with a mechanism of penetrating trauma to the lower urinary tract include lacerations or puncture wounds of the pelvis, perineum, buttocks, or genitalia, as well as gross hematuria or inability to void. CT cystography or fluoroscopy retrograde cystography are usually the most appropriate initial imaging procedures in patients with a mechanism of penetrating trauma to the lower urinary tract. CT of the pelvis with intravenous contrast, pelvic radiography, fluoroscopic retrograde urethrography, and CT of the pelvis without intravenous contrast may be appropriate in some cases. Arteriography, radiographic intravenous urography, CT of the pelvis without and with intravenous contrast, ultrasound, MRI, and nuclear scintigraphy are usually not appropriate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Asunto(s)
Traumatismos Abdominales/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Guías de Práctica Clínica como Asunto , Vejiga Urinaria/lesiones , Sistema Urinario/lesiones , Heridas Penetrantes/diagnóstico por imagen , Traumatismos Abdominales/cirugía , Medios de Contraste , Cistografía/métodos , Medicina Basada en la Evidencia , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Imagen por Resonancia Magnética/métodos , Masculino , Tomografía de Emisión de Positrones/métodos , Control de Calidad , Radiología/normas , Sensibilidad y Especificidad , Sociedades Médicas/normas , Tomografía Computarizada por Rayos X/métodos , Estados Unidos , Uretra/diagnóstico por imagen , Uretra/lesiones , Vejiga Urinaria/diagnóstico por imagen , Sistema Urinario/diagnóstico por imagen
11.
J Am Coll Radiol ; 16(11S): S417-S427, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31685109

RESUMEN

Urothelial cancer is the second most common cancer, and cause of cancer death, related to the genitourinary tract. The goals of surveillance imaging after the treatment of urothelial cancer of the urinary bladder are to detect new or previously undetected urothelial tumors, to identify metastatic disease, and to evaluate for complications of therapy. For surveillance, patients can be stratified into one of three groups: (1) nonmuscle invasive bladder cancer with no symptoms or additional risk factors; (2) nonmuscle invasive bladder cancer with symptoms or additional risk factors; and (3) muscle invasive bladder cancer. This article is a review of the current literature for urothelial cancer and resulting recommendations for surveillance imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.


Asunto(s)
Carcinoma de Células Transicionales/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Guías de Práctica Clínica como Asunto , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/cirugía , Cistectomía/métodos , Cistografía/métodos , Cistoscopía/métodos , Medicina Basada en la Evidencia , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Monitoreo Fisiológico , Clasificación del Tumor , Invasividad Neoplásica/patología , Pronóstico , Control de Calidad , Radiología/normas , Sensibilidad y Especificidad , Sociedades Médicas/normas , Tomografía Computarizada por Rayos X/métodos , Estados Unidos , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía
12.
Ann Biomed Eng ; 47(2): 524-536, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30488309

RESUMEN

To improve the targeting accuracy and reduce procedure time in magnetic resonance imaging (MRI)-guided procedures, a 3D-printed flexible template was developed. The template was printed using flexible photopolymer resin FLFLGR02 in Form 2 printer® (Formlabs, Inc., Somerville, MA). The flexible material gives the template a unique advantage by allowing it to make close contact with human skin and provide accurate insertion with the help of the newly developed OncoNav software. At the back of the template, there is a grid comprised of circular containers filled with contrast agent. At the front of the template, the guide holes between the containers provide space and angular flexibility for needle insertion. MRI scans are initially used to identify tumor position as well as the template location. The OncoNav software then pre-selects a best guide hole for targeting a specific lesion and suggests insertion depth for the physician A phantom study of 13 insertions in a CT scanner was carried out for assessing needle placement accuracy. The mean total distance error between planned and actual insertion is 2.7 mm, the maximum error was 4.78 mm and standard deviation was 1.1 mm. The accuracy of the OncoNav-assisted and template-guided needle targeting is comparable to the robot-assisted procedure. The proposed template is a low-cost, quickly-deployable and disposable medical device. The presented technology will be further evaluated in prostate cancer patients to quantify its accuracy in needle biopsy.


Asunto(s)
Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Agujas , Fantasmas de Imagen , Neoplasias de la Próstata , Programas Informáticos , Humanos , Biopsia Guiada por Imagen/instrumentación , Biopsia Guiada por Imagen/métodos , Masculino , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología
13.
Bull Environ Contam Toxicol ; 100(5): 677-682, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29516138

RESUMEN

The residual levels and persistence of thiram in the soil, water and oil palm seedling leaves were investigated under field conditions. The experimental plots were carried out on a clay loam soil and applied with three treatments namely; manufacturer's recommended dosage (25.6 g a.i. plot-1), manufacturer's double recommended dosage (51.2 g a.i. plot-1), and control (water) were applied. Thiram residues were detected in the soil from day 0 to day 3 in the range of 0.22-27.04 mg kg-1. Low concentrations of thiram were observed in the water and leave samples in the range of 0.27-2.52 mg L-1 and 1.34-12.28 mg kg-1, respectively. Results have shown that thiram has a rapid degradation and has less persistence due to climatic factors. These findings suggest that thiram is safe when applied at manufacturer's recommended dosage on oil palm seedlings due to low residual levels observed in soil and water bodies.


Asunto(s)
Fungicidas Industriales/análisis , Tiram/análisis , Monitoreo del Ambiente , Aceite de Palma , Hojas de la Planta/química , Suelo/química , Contaminantes del Suelo/análisis , Agua , Contaminantes Químicos del Agua/análisis
14.
Environ Monit Assess ; 189(11): 551, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-29022154

RESUMEN

This study focused on the residue detection of the herbicides triclopyr and glufosinate ammonium in the runoff losses from the Tasik Chini oil palm plantation area and the Tasik Chini Lake under natural rainfall conditions in the Malaysian tropical environment. Triclopyr and glufosinate ammonium are post-emergence herbicides. Both herbicides were foliar-sprayed on 0.5 ha of oil palm plantation plots, which were individualized by an uneven slope of 10-15%. Samples were collected at 1, 3, 7, 15, 30, 45, 60, 90, and 120 days after treatment. The concentrations of both herbicides quickly diminished from those in the analyzed sample by the time of collection. The highest residue levels found in the field surface leachate were 0.031 (single dosage, triclopyr), 0.041 (single dosage, glufosinate ammonium), 0.017 (double dosage, triclopyr), and 0.037 µg/kg (double dosage, glufosinate ammonium). The chromatographic peaks were observed at "0" day treatment (2 h after herbicide application). From the applied active ingredients, the triclopyr and glufosinate losses were 0.025 and 0.055%, respectively. The experimental results showed that both herbicides are less potent than other herbicides in polluting water systems because of their short persistence and strong adsorption onto soil clay particles.


Asunto(s)
Aminobutiratos/análisis , Monitoreo del Ambiente/métodos , Glicolatos/análisis , Herbicidas/análisis , Residuos de Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Arecaceae/crecimiento & desarrollo , Malasia , Lluvia , Suelo/química
15.
Am J Nucl Med Mol Imaging ; 7(4): 195-203, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28913158

RESUMEN

89Zr-panitumumab is a novel immuno-PET radiotracer. A fully humanized IgG2 antibody, panitumumab binds with high affinity to the extracellular ligand binding domain of EGFR. Immuno-PET with radiolabeled panitumumab is a non-invasive method that could characterize EGFR expression in tumors and metastatic lesions. It might also assist in selecting patients likely to benefit from targeted therapy as well as monitor response and drug biodistribution for dosing guidance. Our objective was to calculate the maximum dosing for effective imaging with minimal radiation exposure in a small subset. Three patients with metastatic colon cancer were injected with approximately 1 mCi (37 MBq) of 89Zr-panitumumab IV. Whole body static images were then obtained at 2-6 hours, 1-3 days and 5-7 days post injection. Whole organ contours were applied to the liver, kidneys, spleen, stomach, lungs, bone, gut, heart, bladder and psoas muscle. From these contours, time activity curves were derived and used to calculate mean resident times which were used as input into OLINDA 1.1 software for dosimetry estimates. The whole body effective dose was estimated between 0.264 mSv/MBq (0.97 rem/mCi) and 0.330 mSv/MBq (1.22 rem/mCi). The organ which had the highest dose was the liver which OLINDA estimated between 1.9 mGy/MBq (7.2 rad/mCi) and 2.5 mGy/MBq (9 rad/mCi). The effective dose is within range of extrapolated estimates from mice studies. 89Zr-panitumumab appears safe and dosimetry estimates are reasonable for clinical imaging.

16.
Bull Environ Contam Toxicol ; 96(1): 120-4, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26546229

RESUMEN

The mobility of (14)C-chlorpyrifos using soil TLC was investigated in this study. It was found that chlorpyrifos was not mobile in clay, clay loam and peat soil. The mobility of (14)C-chlorpyrifos and non-labelled chlorpyrifos was also tested with silica gel TLC using three types of developing solvent hexane (100%), hexane:ethyl acetate (95:5, v/v); and hexane:ethyl acetate (98:2, v/v). The study showed that both the (14)C-labelled and non-labelled chlorpyrifos have the same Retardation Factor (Rf) for different developing solvent systems. From the soil column study on mobility of chlorpyrifos, it was observed that no chlorpyrifos residue was found below 5 cm depth in three types of soil at simulation rainfall of 20, 50 and 100 mm. Therefore, the soil column and TLC studies have shown similar findings in the mobility of chlorpyrifos.


Asunto(s)
Cloropirifos/análisis , Insecticidas/análisis , Contaminantes del Suelo/análisis , Silicatos de Aluminio/química , Arecaceae , Cloropirifos/química , Cromatografía en Capa Delgada , Arcilla , Insecticidas/química , Malasia , Suelo/química , Contaminantes del Suelo/química , Solventes
17.
PLoS One ; 10(10): e0138170, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26437264

RESUMEN

Triazine-2-(14)C metsulfuron-methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-(14)C metsulfuron-methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC) equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery column (250 x 4.6 mm, 5 µm), and PRP-1 column (305 x 7.0 mm, 10 µm) was used for the HPLC analysis. The radioactivity was determined by a Liquid Scintillation Counter (LSC) in scintillation fluid. The soil used was both sterilized and non-sterilized in order to observe the involvement of soil microbes. The estimated DT50 and DT90 values of metsulfuron-methyl in a non-sterile system were observed to be 13 and 44 days, whereas in sterilized soil, the DT50 and DT90 were 31 and 70 days, respectively. The principal degradation product after 60 days was CO2. The higher cumulative amount of (14)CO2 in (14)C-triazine in the non-sterilized soil compared to that in the sterile system suggests that biological degradation by soil micro-organisms significantly contributes to the dissipation of the compound. The major routes of degradation were O-demethylation, sulfonylurea bridge cleavage and the triazine "ring-opened."


Asunto(s)
Arecaceae/crecimiento & desarrollo , Arilsulfonatos/química , Herbicidas/química , Contaminantes del Suelo/química , Suelo/química , Triazinas/química , Arilsulfonatos/metabolismo , Herbicidas/metabolismo , Cinética , Oxígeno/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Triazinas/metabolismo
18.
J Clin Oncol ; 31(18): 2296-302, 2013 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-23630200

RESUMEN

PURPOSE: Alveolar soft part sarcoma (ASPS) is a rare, highly vascular tumor, for which no effective standard systemic treatment exists for patients with unresectable disease. Cediranib is a potent, oral small-molecule inhibitor of all three vascular endothelial growth factor receptors (VEGFRs). PATIENTS AND METHODS: We conducted a phase II trial of once-daily cediranib (30 mg) given in 28-day cycles for patients with metastatic, unresectable ASPS to determine the objective response rate (ORR). We also compared gene expression profiles in pre- and post-treatment tumor biopsies and evaluated the effect of cediranib on tumor proliferation and angiogenesis using positron emission tomography and dynamic contrast-enhanced magnetic resonance imaging. RESULTS: Of 46 patients enrolled, 43 were evaluable for response at the time of analysis. The ORR was 35%, with 15 of 43 patients achieving a partial response. Twenty-six patients (60%) had stable disease as the best response, with a disease control rate (partial response + stable disease) at 24 weeks of 84%. Microarray analysis with validation by quantitative real-time polymerase chain reaction on paired tumor biopsies from eight patients demonstrated downregulation of genes related to vasculogenesis. CONCLUSION: In this largest prospective trial to date of systemic therapy for metastatic ASPS, we observed that cediranib has substantial single-agent activity, producing an ORR of 35% and a disease control rate of 84% at 24 weeks. On the basis of these results, an open-label, multicenter, randomized phase II registration trial is currently being conducted for patients with metastatic ASPS comparing cediranib with another VEGFR inhibitor, sunitinib.


Asunto(s)
Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Quinazolinas/uso terapéutico , Sarcoma de Parte Blanda Alveolar/tratamiento farmacológico , Sarcoma de Parte Blanda Alveolar/genética , Adulto , Anorexia/inducido químicamente , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Diarrea/inducido químicamente , Femenino , Redes Reguladoras de Genes , Humanos , Hipertensión/inducido químicamente , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Estudios Prospectivos , Quinazolinas/efectos adversos , Quinazolinas/farmacocinética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sarcoma de Parte Blanda Alveolar/metabolismo , Resultado del Tratamiento , Adulto Joven
19.
BJU Int ; 111(8): 1269-80, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23419134

RESUMEN

OBJECTIVE: To assess the efficacy and toxicity of cediranib, a highly potent inhibitor of vascular endothelial growth factor receptor tyrosine kinases, in patients with metastatic castration-resistant prostate cancer (CRPC) previously treated with docetaxel-based therapy. PATIENTS AND METHODS: The study used a Simon two-stage trial design, which required at least two of 12 patients in the first cohort to be progression-free at 6 months. We enrolled a total of 35 evaluable patients who all received cediranib 20 mg orally daily. In a second cohort, 23 additional patients received prednisone 10 mg daily with cediranib. Endpoints included tumour response, progression-free survival (PFS), overall survival (OS), vascular permeability via dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and toxicity. RESULTS: A total of 59 patients were enrolled, of whom 67% had received two or more previous chemotherapy regimens. Six of 39 patients with measurable disease had confirmed partial responses and one had an unconfirmed partial response. At 6 months, 43.9% of patients were progression-free; the median PFS and OS periods for all patients were 3.7 months and 10.1 months, respectively. We found that the DCE-MRI variables baseline transport constant (Ktrans ) and rate constant at day 28 were significantly associated with PFS in univariate analyses, but only baseline Ktrans remained significant when considered jointly. The most frequent toxicities were hypertension, fatigue, anorexia and weight loss; the addition of prednisone reduced the incidence of constitutional toxicities. CONCLUSION: This study demonstrated that cediranib was generally well tolerated with some anti-tumour activity in highly pretreated patients with metastatic CRPC who had progressive disease after docetaxel-based therapy.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Orquiectomía , Neoplasias de la Próstata/tratamiento farmacológico , Quinazolinas/administración & dosificación , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Administración Oral , Anciano , Relación Dosis-Respuesta a Droga , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Inhibidores de Proteínas Quinasas/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento
20.
J Environ Biol ; 33(3): 573-7, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-23029905

RESUMEN

Laboratory experiments were conducted to evaluate adsorption, desorption and mobility of metsulfuron-methyl in soils of the oil palm agroecosystem consisting of the Bernam, Selangor, Rengam and Bongor soil series. The lowest adsorption of metsulfuron-methyl occurred in the Bongor soil (0.366 ml g(-1)), and the highest in the Bemam soil (2.837 ml g(-1). The K(fads) (Freundlich) values of metsulfuron-methyl were 0.366, 0.560, 1.570 and 2.837 ml g(-1) in Bongor, Rengam, Selangor and Bemam soil, respectively. The highest K(fdes) value of metsulfuron-methyl, observed in the Bemam soil, was 2.563 indicating low desorption 0.280 (relatively strong retention). In contrast, the lowest K(fdes) value of 0.564 was observed for the Bongor soil, which had the lowest organic matter (1.43%) and clay content (13.2%). Soil organic matter and clay content were the main factors affecting the adsorption of metsulfuron-methyl. The results of the soil column leaching studies suggested that metsulfuron-methyl has a moderate potential for mobility in the Bernam and Bongor soil series with 19.3% and 39%, respectively for rainfall at 200 mm. However, since metsulfuron-methyl is applied at a very low rate (the maximum field application rate used was 30 g ha(-1)) and is susceptible to biodegradation, the potential forground water contamination is low.


Asunto(s)
Arecaceae , Arilsulfonatos/análisis , Herbicidas/análisis , Residuos de Plaguicidas/análisis , Suelo/análisis , Adsorción , Agricultura , Malasia
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