435 research outputs found
A Novel PET Imaging Probe for the Detection and Monitoring of Translocator Protein 18 kDa Expression in Pathological Disorders
A new fluorine-substituted ligand, compound 1 (CB251), with a very high affinity (Ki = 0.27 ± 0.09 nM) and selectivity for the 18-kDa translocator protein (TSPO), is presented as an attractive biomarker for the diagnosis of neuroinflammation, neurodegeneration and tumour progression. To test compound 1 as a TSPO PET imaging agent in vivo, 2-(2-(4-(2-[18F]fluoroethoxy)phenyl)-6,8-dichloroimidazo[1,2-a]pyridin-3-yl)-N,N-dipropylacetamide ([18F]1; [18F]CB251) was synthesized by nucleophilic aliphatic substitution in a single-step radiolabelling procedure with a 11.1 ± 3.5% (n = 14, decay corrected) radiochemical yield and over 99% radiochemical purity. In animal PET imaging studies, [18F]CB251 provided a clearly visible image of the inflammatory lesion with the binding potential of the specifically bound radioligand relative to the non-displaceable radioligand in tissue (BPND 1.83 ± 0.18), in a neuroinflammation rat model based on the unilateral stereotaxic injection of lipopolysaccharide (LPS), comparable to that of [11C]PBR28 (BPND 1.55 ± 0.41). [18F]CB251 showed moderate tumour uptake (1.96 ± 0.11%ID/g at 1 h post injection) in human glioblastoma U87-MG xenografts. These results suggest that [18F]CB251 is a promising TSPO PET imaging agent for neuroinflammation and TSPO-rich cancers
A Rare Case of a Signet Ring Cell Carcinoma of the Colon Mimicking a Juvenile Polyp
Primary signet ring cell carcinoma (SRC) of colon at early stage is quite rare. Only 26 cases were reported until now. We report an early stage of primary SRC which was misdiagnosed as a juvenile polyp and treated with polypectomy followed by surgical resection. A 21-year-old male was administered for hematochezia. Abdominopelvic enhanced computed tomography revealed a polyp with active bleeding at the proximal rectum just below the rectosigmoid junction. Colonoscopy examination revealed a colon polyp with 0.5 cm sized head. Polypectomy was performed with snare and the polyp was completely removed. Biopsy revealed SRC. Surgical resection was also performed and there were no residual tumor or lymph node metastasis in the surgical specimen
Could Fractional Exhaled Nitric Oxide Test be Useful in Predicting Inhaled Corticosteroid Responsiveness in Chronic Cough? A Systematic Review
© 2016 Background Fractional exhaled nitric oxide (FENO) is a safe and convenient test for assessing T H 2 airway inflammation, which is potentially useful in the management of patients with chronic cough. Objective To summarize the current evidence on the diagnostic usefulness of FENO for predicting inhaled corticosteroid (ICS) responsiveness in patients with chronic cough. Methods A systematic literature review was conducted to identify articles published in peer-reviewed journals up to February 2015, without language restriction. We included studies that reported the usefulness of FENO (index test) for predicting ICS responsiveness (reference standard) in patients with chronic cough (target condition). The data were extracted to construct a 2 × 2 accuracy table. Study quality was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Results We identified 5 original studies (2 prospective and 3 retrospective studies). We identified considerable heterogeneities in study design and outcome definitions, and thus were unable to perform a meta-analysis. The proportion of ICS responders ranged from 44% to 59%. Sensitivity and specificity ranged from 53% to 90%, and from 63% to 97%, respectively. The reported area under the curve ranged from abou t 0.60 to 0.87; however, studies with a prospective design and a lower prevalence of asthma had lower area under the curve values. None measured placebo effects or objective cough frequency. Conclusions We did not find strong evidence to support the use of FENO tests for predicting ICS responsiveness in chronic cough. Further studies need to have a randomized, placebo-controlled design, and should use validated measurement tools for cough. Standardization would facilitate the development of clinical evidence
Distal Cholangiocarcinoma with Gastric Metastasis Mimicking Early Gastric Cancer
We report an unusual case of distal cholangiocarcinoma with gastric metastasis mimicking early gastric cancer. A 67-year-old woman presented with a 4-month history of abdominal pain after eating. Computed tomography showed a malignant tumor of the common bile duct located just above the intrapancreatic segment, and endoscopy revealed a 2-cm, flat, elevated lesion with convergence of the surrounding folds, situated at the gastric angle. Based on the endoscopic biopsy results, an adenocarcinoma, thought to be an early gastric cancer, was diagnosed. The patient underwent Whipples's operation. Histopathological findings showed that the adenocarcinomatous tissue was clearly demarcated and infiltrated the gastric mucosa and submucosa, leaving the gastric superficial mucosa intact. Both tumors showed similar pathological features and were positive for cytokeratin (CK)-19 and CK-7. These finding suggest distal cholangiocarcinoma with gastric metastasis
Hysteroscopic Resection of the Vaginal Septum in Uterus Didelphys with Obstructed Hemivagina: A Case Report
Uterus didelphys with obstructed hemivagina and ipsilateral renal agenesis is a rare congenital anomaly. Excision of the obstructed vaginal septum is the treatment of choice for symptom relief and the preservation of reproductive capability. A 14-yr-old girl complained of persistent vaginal spotting following each menstruation. Pelvic magnetic resonance imaging revealed a uterus didelphys with left hematocolpos and ipsilateral renal agenesis. Instead of conventional transvaginal excision of the vaginal septum, we used hysteroscopic excision under transabdominal ultrasonographic guidance to preserve the integrity of the hymen. The postoperative course was uneventful, and clinical symptoms were completely resolved after this intervention. Resectoscopic excision of the vaginal septum was found to be easy, safe, effective, and appropriate for young women as it preserved hymen integrity. We believe that this is the first Korean report on the use of a hysteroscopy for vaginal septum resection in a patient with uterus didelphys with obstructed hemivagina
Attitude Control Strategy for HAUSAT-2 with Pitch Bias Momentum System
The HAUSAT-2 is a 25kg class micro/nanosatellite which is being developed by graduate students at the Space System Research Laboratory(SSRL). This paper addresses a newly proposed strategy for detumbling the HAUSAT-2 and starting up a momentum wheel, and also studies performance validation and application ranges of such method through simulation. B-dot logic is generally used for controlling the initial tip-off rate. However, it has the disadvantage of taking a relatively long time to control the initial tip-off rate. To solve this problem, this paper suggests a new detumbling control method to be able to adapt to micro/nanosatellite with the pitch bias momentum system, and has shown simulation results. Proposed detumbling method was able to control the angular rate within 20 minutes which is a significant reduction compared to conventional methods. In addition, the momentum wheel initial start-up must be done under stable conditions, and conventional pitch spin-stabilized initial wheel start-up method is commonly used. The performance of the method is compared and verified through simulation. The overall result shows much faster control time compared to the conventional methods, and achievement of the nominal wheel speed and 3-axes stabilization while maintaining stability
- …