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1.
Org Lett ; 21(14): 5719-5724, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31265315

RESUMO

N,N'-Acetals are sensitive compounds, and the challenging asymmetric synthesis of acyclic N,N'-acetals by the general addition of amines to ketimines has never been reported so far. In this study, highly enantioselective addition of aryl amines to isatin-derived ketimines catalyzed by chiral urea derived from quinine was developed. A series of new acyclic N,N'-acetals were constructed by this protocol in high to excellent yields (78-99%) and high to excellent enantioselectivities (76-96% ee).

2.
Jpn J Radiol ; 37(9): 636-641, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31270660

RESUMO

PURPOSE: To investigate the influence of virtual monochromatic spectral (VMS) CT images at different energy levels on the effectiveness of a motion correction technique (SSF) in dual-energy Spectral coronary CT angiography (CCTA). MATERIALS AND METHODS: 29 cases suspected of or diagnosed with coronary artery disease underwent Spectral CCTA using a prospective ECG triggering with 250 ms padding time. SSF was applied to the determined least-motion phase to generate 6 additional sets of VMS images with energy levels from 40 to 100 keV. CT value and standard deviation (SD) in the aortic root and epicardial adipose tissue were measured. Image quality of the RCA, LAD and LCX was evaluated on a per-vessel basis in each patient. Two reviewers evaluated the artery using the score of the segment. RESULTS: The low energy VMS images increased CT value and image noise compared with higher-energy VMS images, except 90 keV and 100 keV. The CNR of 40-70 keV were higher than those of 80-100 keV (P < 0.05). The image quality scores for images at 50-80 keV were higher than those of 40, 90, and 100 keV (P < 0.05), and the VMS image quality at 50 keV and 60 keV with SSF was the highest. CONCLUSION: SSF can effectively reduce the motion artifacts when coronary vessels have suitable contrast enhancement which can be achieved by adjusting energy levels of VMS images.

3.
Int. braz. j. urol ; 45(3): 617-620, May-June 2019.
Artigo em Inglês | LILACS-Express | ID: biblio-1012325

RESUMO

ABSTRACT Objective: Pyeloplasty is considered the gold standard treatment for ureteropelvic junction obstruction (UPJO). However, the failure rate of pyeloplasty is as high as 10% and repeat pyeloplasty is more difficult. This study aimed to evaluate the efficacy of balloon dilatation for failed pyeloplasty in children. Materials and Methods: Between 2011 and 2017, 15 patients, aged 6 months to 14 years, were treated with balloon dilation for restenosis of UPJO after a failed pyeloplasty. Ultrasound and intravenous urography were used to evaluate the primary outcome. Success was defined as the relief of symptoms and improvement of hydronephrosis, which was identified by ultrasound at the last follow-up. Results: All patients successfully completed the operation, 13 patients by retrograde approach and 2 patients by antegrade approach. Thirteen patients were followed for a median of 15 (4 to 57) months and 2 patients were lost to follow-up. Resolution of the hydronephrosis was observed in 5 cases. The anteroposterior diameter (APD) of the pelvis decreased by an average of 12.4 ± 14.4mm. Eight patients needed another surgery. The average postoperative hospital stay was 1.78 ± 1.4 days. Two patients experienced fever after balloon dilation. No other complications were found. Conclusions: Balloon dilatation surgery is safe for children, but it is not recommended for failed pyeloplasty in that group of patients, owing to the low success rate.

4.
Medicine (Baltimore) ; 98(7): e14438, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30762753

RESUMO

A new method of quantitative computed tomography (CT) measurements of pulmonary vessels are applicable to morphological studies and may be helpful in defining the progression of emphysema in smokers. However, limited data are available on the relationship between the smoking status and pulmonary vessels alteration established in longitudinal observations. Therefore, we investigated the change of pulmonary vessels on CTs in a longitudinal cohort of smokers.Chest CTs were available for 287 current smokers, 439 non-smokers, and 80 former smokers who quit smoking at least 2 years after the baseline CT. CT images obtained at the baseline and 1 year later were assessed by a new quantitative CT measurement method, computing the total number of pulmonary vessels (TNV), mean lung density (MLD), and the percentage of low-attenuation areas at a threshold of -950 (density attenuation area [LAA]%950). Analysis of variance (ANOVA) and the independent sample t test were used to estimate the influence of the baseline parameters. The t paired test was employed to evaluate the change between the baseline and follow-up results.The current smokers related to have higher whole-lung MLD, as well as less and lower TNV values than the non-smokers (P <.05). But no significant differences in LAA%950 were found between smokers and non-smokers. After one year, the increase in LAA%950 was more rapid in the current (additional 0.3% per year, P <. 05-.01) than in the former smokers (additional 0.2% per year, P = .3). Additionally, the decline in TNV was faster in the current (additional -1.3 per year, P <.05-.01) than that in the former smokers (additional -0.2 per year, P = .6). Current smoke, pack-years, weight, and lung volume independently predicted TNV at baseline (P <.001) in multivariate analysis.The findings of this study reveal that the decline in the pulmonary vessels in smokers can be measured and related to their smoking status.


Assuntos
Pulmão/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Veias Pulmonares/diagnóstico por imagem , Fumar/patologia , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Idoso , Progressão da Doença , Seguimentos , Humanos , Estudos Longitudinais , Pulmão/irrigação sanguínea , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Enfisema Pulmonar/etiologia , Enfisema Pulmonar/patologia , Veias Pulmonares/patologia , Fumar/efeitos adversos , Abandono do Hábito de Fumar , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos
5.
PLoS One ; 14(1): e0206810, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30703102

RESUMO

OBJECTIVES: To compare the efficacy and safety of percutaneous nephrolithotomy (PCNL) and open surgery (OS) for surgical treatment of patients with staghorn stones based on published literatures. MATERIALS AND METHODS: A comprehensive literature search of Pubmed, Embase, CNKI and Cochrane Library was conducted to identify studies comparing outcomes of PCNL and OS for treating patients with staghorn stones up to Jan 2018. RESULTS: There was no significant difference in final-SFR between PCNL and OS (odds ratio[OR]: 1.17; 95% confidence interval [CI]: 0.64, 2.15; p = 0.61), while PCNL provided a significantly lower immediate-SFR compared with OS (OR: 0.29; 95% CI: 0.16, 0.51; P < 0.0001). PCNL provided significantly lower overall complication rate, shorter operative times, hospitalization times, less blood loss and blood transfusion compared with OS (OR: 0.59; 95% CI: 0.41, 0.84; P = 0.004), (weighted mean difference [WMD]: -59.01mins; 95% CI: -81.09, -36.93; p < 0.00001), (WMD: -5.77days; 95% CI: -7.80, -3.74; p < 0.00001), (WMD: -138.29ml; 95% CI: -244.98, -31.6; p = 0.01) and (OR: 0.44; 95% CI: 0.29, 0.68; P = 0.00002), respectively. No significant differences were found in minor complications (Clavien I-II) (OR: 0.72; 95% CI: 0.47, 1.09; p = 0.12) and major complications (Clavien III-V) (OR: 0.5; 95% CI: 0.23, 1.08; P = 0.08). In subgroup analysis, there were no significant differences for overall complications and operative times between mini-PCNL and OS. In sensitivity analysis, there was no significant difference for overall complications between PCNL and OS. CONCLUSION: Our analysis suggested that standard PCNL turns out to be a safe and feasible alternative for patients with staghorn stones compared to OS or mini-PCNL. Because of the inherent limitations of the included studies, further large sample, prospective, multi-centric and randomized control trials should be undertaken to confirm our findings.

6.
Acad Radiol ; 26(7): 878-884, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30803898

RESUMO

PURPOSE: To investigate the value of dual-energy spectral computed tomography (CT) imaging in the differential diagnosis of small bowel adenocarcinoma (SBA) from primary small intestinal lymphoma (PSIL). MATERIALS AND METHODS: We retrospectively analyzed the images of 27 SBA cases and 15 PSIL cases. These patients underwent spectral CT imaging in the arterial phase (AP) and venous phase (VP). CT attenuation values of tumors at different energy levels were measured to generate spectral attenuation curve and to calculate curve slope (λHU). Iodine concentration (IC) in tumors at AP and VP were measured and normalized to that of aorta as normalized iodine concentration (NIC). Independent samples t test was used to analyze the spectral CT parameters; Receiver operating characteristic curves were generated to evaluate the diagnostic efficacy of each parameter. RESULTS: There were significant differences between SBA and PSIL in IC (2.09 ± 0.71 vs 1.33 ± 0.15 mg/ml), NIC (0.20 ± 0.06 vs 0.13 ± 0.02) and slope (λHU) (2.78 ± 1.06 vs 1.86 ± 0.30) in AP and (1.86 ± 0.68 vs 1.37 ± 0.18 mg/ml for IC; 0.47 ± 0.13 vs 0.33 ± 0.02 for NIC and 2.00 ± 0.56 vs 1.50 ± 0.26 for λHU) in VP (all p < 0.05). For the CT value measurement, there were significant differences between SBA and PSIL in the 40-60keV energy range (p < 0.05), but not in the 70-140keV range (p > 0.05). Using 1.38 mg/ml as a threshold value for iodine concentration at AP, one could obtain the area-under-curve of 0.93 for receiver operating characteristic study and sensitivity of 94% and specificity of 85% for differentiating SBA from PSIL. The sensitivity and specificity values were significantly higher than the respective values of 62% and 60% with the conventional CT numbers at 70keV. CONCLUSION: Quantitative parameters obtained in spectral CT, especially iodine concentration in AP, provide high accuracy for differentiating SBA from PSIL.

7.
Int Braz J Urol ; 45(3): 617-620, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30676306

RESUMO

OBJECTIVE: Pyeloplasty is considered the gold standard treatment for ureteropelvic junction obstruction (UPJO). However, the failure rate of pyeloplasty is as high as 10% and repeat pyeloplasty is more difficult. This study aimed to evaluate the efficacy of balloon dilatation for failed pyeloplasty in children. MATERIALS AND METHODS: Between 2011 and 2017, 15 patients, aged 6 months to 14 years, were treated with balloon dilation for restenosis of UPJO after a failed pyeloplasty. Ultrasound and intravenous urography were used to evaluate the primary outcome. Success was defined as the relief of symptoms and improvement of hydronephrosis, which was identified by ultrasound at the last follow-up. RESULTS: All patients successfully completed the operation, 13 patients by retrograde approach and 2 patients by antegrade approach. Thirteen patients were followed for a median of 15 (4 to 57) months and 2 patients were lost to follow-up. Resolution of the hydronephrosis was observed in 5 cases. The anteroposterior diameter (APD) of the pelvis decreased by an average of 12.4 ± 14.4mm. Eight patients needed another surgery. The average postoperative hospital stay was 1.78 ± 1.4 days. Two patients experienced fever after balloon dilation. No other complications were found. CONCLUSIONS: Balloon dilatation surgery is safe for children, but it is not recommended for failed pyeloplasty in that group of patients, owing to the low success rate.


Assuntos
Pelve Renal/cirurgia , Obstrução Ureteral/cirurgia , Cateterismo Urinário/métodos , Procedimentos Cirúrgicos Urológicos/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Hidronefrose/cirurgia , Lactente , Pelve Renal/diagnóstico por imagem , Masculino , Reprodutibilidade dos Testes , Resultado do Tratamento , Ultrassonografia/métodos , Obstrução Ureteral/diagnóstico por imagem , Cateterismo Urinário/instrumentação , Urografia/métodos , Procedimentos Cirúrgicos Urológicos/instrumentação
8.
Acad Radiol ; 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30660470

RESUMO

RATIONALE AND OBJECTIVES: To compare upper abdominal computed tomography (CT) image quality of new model-based iterative reconstruction (MBIR) with low-contrast resolution preference (MBIRNR40), conventional MBIR (MBIRc), and adaptive statistical iterative reconstruction (ASIR) at low dose with ASIR at routine-dose. MATERIALS AND METHODS: Study included phantom and 60 patients who had initial and follow-up CT scans. For patients, the delay phase was acquired at routine-dose (noise index = 10 HU) for the initial scan and low dose (noise index = 20 HU) for the follow-up. The low-dose CT was reconstructed with 40% and 60% ASIR, MBIRc, and MBIRNR40, while routine-dose CT was reconstructed with 40% ASIR. CT value and noise measurements of the subcutaneous fat, back muscle, liver, and spleen parenchyma were compared using one-way ANOVA. Two radiologists used semiquantitative 7-scale (-3 to +3) to rate image quality and artifacts. RESULTS: The phantom study revealed superior low-contrast resolution with MBIRNR40. For patient scans, the CT dose index for the low-dose CT was 3.00 ± 1.32 mGy, 75% lower than the 11.90 ± 4.75 mGy for the routine-dose CT. Image noise for the low-dose MBIRNR40 images was significantly lower than the low-dose MBIRc and ASIR images, and routine-dose ASIR images (p < 0.05). Subjective ratings showed higher image quality for low-dose MBIRNR40, with lower noise, better low-contrast resolution for abdominal structures, and finer lesion contours than those of low-dose MBIRc and ASIR images, and routine-dose ASIR images (p < 0.05). CONCLUSION: MBIRNR40 with low-contrast resolution preference provides significantly lower noise and better image quality than MBIRc and ASIR in low-dose abdominal CT; significantly better objective and subjective image quality than the routine-dose ASIR with 75% dose reduction.

9.
Magn Reson Imaging ; 57: 271-276, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30557591

RESUMO

OBJECTIVES: High resolution CT is the most commonly used radiological method for differentiating benign from malignant peripheral solid pulmonary masses, however, some of them are not easily diagnosed by morphology alone. Furthermore, due to the radiation dose, it is unsuitable for patients with disorders requiring repeated examinations over prolonged periods. The aims of this study were to evaluate whether a combination of diffusion-weighted images (DWI) and free-breathing radial 3D fat-suppressed T1-weighted gradient echo (radial volumetric interpolated breath-hold examination, radial VIBE) sequence can enable discrimination between benign from malignant peripheral solid pulmonary masses. MATERIALS AND METHODS: Both chest CT scan and MR imaging with radial VIBE and DWI were obtained from 47 patients; 30 males and 17 females (mean age 64 years old; age range 48-83 years old). Benign and malignant peripheral solid pulmonary masses were conclusively identified by pathology results. Two radiologists independently reviewed all the images and record radiological features including morphological signs on radial VIBE, CT images, and ADC value. Receiver operating characteristic (ROC) was used to analyze the capability of radial VIBE as well as DWI to distinguish malignant from benign peripheral solid pulmonary masses. RESULTS: In 77% of patients, malignant peripheral solid pulmonary masses were found. Morphological signs of mediastinal lymph node enlargement and lobulation were more easily found in malignant masses in both radial VIBE (mediastinal lymph node enlargement: p = 0.033, lobulation: p = 0.039) and CT (mediastinal lymph node enlargement: p = 0.004, lobulation: p = 0.012). The ADC value were also significant difference between benign and malignant groups (p = 0.001). Combined ADC value with radial VIBE was a most specific test than routine-dose CT (86.1% vs 75%, p < 0.001), but less sensitive than routine-dose CT (81.8% vs 90.9%; p < 0.001) for malignant peripheral solid pulmonary masses detection. Diagnostic accuracy was 89% for combining ADC value with radial VIBE, and 85% for routine-dose CT. CONCLUSIONS: Combination of morphological signs and ADC value seems to improve differentiating malignant from benign peripheral solid pulmonary masses. Especially in patients unable to endure radiation exposure, suspend respiration, radial VIBE provides similar morphological signs displaying to those on routine-dose CT.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Imagem Tridimensional/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Respiração , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC
10.
Org Biomol Chem ; 16(46): 8927-8932, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30431642

RESUMO

A highly diastereo- and enantioselective Mannich reaction of isatin-derived ketimines with oxo-indanecarboxylates catalyzed by chiral thiourea derived from hydroquinidine has been developed. A series of 3-substituted 3-amino-oxindoles containing assembled bicyclic rings linked by a C-C bond were constructed by this protocol in excellent yields (92-99%) with high enantioselectivities (85-99% ee) and diastereoselectivities (up to >99 : 1 dr).

11.
PLoS One ; 13(10): e0206048, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30339676

RESUMO

OBJECTIVE: To compare the efficacy and safety of micropercutaneous nephrolithotomy (Microperc) and retrograde intrarenal surgery (RIRS) in treating renal stones using published literature. METHODS: A systematic literature review was performed on August 21, 2017, using PubMed, Embase, and Cochrane Library databases in accordance with the PRISMA guidelines. Summarized mean differences (MDs) or odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the differences in outcomes between Microperc and RIRS. RESULTS: A total of nine studies (7 in adult patients and 2 in pediatric patients) containing 842 patients (381 Microperc cases and 461 RIRS cases) with renal stones were included in this analysis. Among the adult patients, Microperc was associated with higher stone-free rate(SFR)(OR: 1.6; 95% CI, 1.03 to 2.48), significantly longer hospital stays (MD: 0.66 day; 95% CI, 0.17 to 1.15), longer fluoroscopy time (MD: 78.12 s; 95% CI, 66.08 to 90.15), and larger decreases in hemoglobin (MD: 0.59 g/dl; 95% CI, 0.16 to 1.02) than was RIRS. No significant differences were observed with respect to operative time, stone-free rate, complication rate or auxiliary procedures. CONCLUSIONS: Our results demonstrated that Microperc might be more effective in adult patients than RIRS will due to its higher SFR. However, longer hospital stays, longer fluoroscopy time and a larger decrease in hemoglobin should be considered cautiously.

12.
Cell Commun Signal ; 16(1): 62, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30241478

RESUMO

BACKGROUND: TEM8 is a cell membrane protein predominantly expressed in tumor endothelium, which serves as a receptor for the protective antigen (PA) of anthrax toxin. However, the physiological ligands for TEM8 remain unknown. RESULTS: Here we identified uPA as an interacting partner of TEM8. Binding of uPA stimulated the phosphorylation of TEM8 and augmented phosphorylation of EGFR and ERK1/2. Finally, TEM8-Fc, a recombinant fusion protein comprising the extracellular domain of human TEM8 linked to the Fc portion of human IgG1, efficiently abrogated the interaction between uPA and TEM8, blocked uPA-induced migration of HepG2 cells in vitro and inhibited the growth and metastasis of human MCF-7 xenografts in vivo. uPA, TEM8 and EGFR overexpression and ERK1/2 phosphorylation were found co-located on frozen cancer tissue sections. CONCLUSIONS: Taken together, our data provide evidence that TEM8 is a novel receptor for uPA, which may play a significant role in the regulation of tumor growth and metastasis.

13.
BJU Int ; 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30253029

RESUMO

OBJECTIVES: To evaluate the long-term outcomes of patients undergoing observation of asymptomatic renal calculi and identify factors associated with stone-related events. PATIENTS AND METHODS: Patients with asymptomatic renal calculi electing active surveillance of their stones were retrospectively reviewed. Patients underwent annual ultrasonography and clinical visits with standardised questions regarding the development of symptoms or complications from calculi. Spontaneous stone passage, stone growth, development of stone-related symptoms, and requirement for intervention during follow-up were deemed as stone-related events. RESULTS: Between 2007 and 2017, 293 patients were reviewed to evaluate the natural history of asymptomatic renal calculi. The mean follow-up was 4.2 years. Overall incidences of spontaneous passage, stone growth, development of stone-related symptoms, and requirement of intervention were 32.1%, 16.7%, 28.3% and 12.3%, respectively. Stones >5 mm and lower pole stones were significantly less likely to pass spontaneously. Patients with diabetes mellitus (DM), hyperuricaemia or non-lower calyceal stone were more likely to experience stone growth. Stones >5 mm or non-lower pole stones were more likely to become symptomatic. Significant predictors of surgical intervention were stone size (>5 mm) and patients' age (>60 years). Primary therapy was extracorporeal shockwave lithotripsy in 33 patients and flexible ureteroscopy in three. CONCLUSION: The natural history of asymptomatic renal stones rarely requires intervention, although they do have a slightly higher rate of symptomatic events and growth over the intermediate term. In particular, patients with stones >5 mm, DM, hyperuricaemia, or non-lower calyceal stones are at higher risk of developing stone-related events, and should therefore be recommended for regular follow-up.

14.
Acad Radiol ; 25(12): 1526-1532, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30017502

RESUMO

OBJECTIVE: We aimed to evaluate a new model-based iterative reconstruction (MBIRn) algorithm either with spatial resolution and noise reduction balance (MBIRSTND) or spatial resolution preference (MBIRRP20) for quantitative analysis of airway in low-dose chest computed tomography (CT) with a computer-aided detection (CAD) software, in comparison to adaptive statistical iterative reconstruction (ASIR) in routine-dose CT. METHODS: Thirty patients who underwent both the routine-dose (noise index [NI] = 14 HU) and low-dose (at 30% level with NI = 28 HU) CT examination for pulmonary disease were included. Image acquisition was performed with 120 kVp tube voltage and automatic tube current modulation. Routine-dose scans were reconstructed with ASIR, whereas low-dose scans were reconstructed with ASIR, MBIRSTND, and MBIRRP20. Airway dimensions of the right middle lobe bronchus from the four reconstructions were measured using CAD software. Two radiologists used a semiquantitative 5 scoring criteria (-2, inferior to; +2, superior to; -1 slightly inferior to; +1, slightly superior to; and 0, equal to ASIR in routine-dose CT) to rate the subjective image quality of MBIRSTND and MBIRRP20 of airway trees. The paired t test and Wilcoxon signed-rank test were used for statistical comparison. RESULTS: The low-dose CT provided 70.76% dose reduction compared to the routine-dose CT (0.88 ± 0.83 mSv vs 3.01 ± 1.89 mSv). MBIRSTND and MBIRRP20 with low-dose CT provided longer bronchial length measurements and were better in measurement variability and continuity and completeness of bronchial walls than ASIR in routine-dose CT (P < .05). MBIRSTND was better for subjective noise and MBIRRP20 for showing distal branches. CONCLUSIONS: MBIRSTND and MBIRRP20 algorithms provide better airway quantification at 30% of the radiation dose, compared to ASIR at routine-dose CT.

15.
Br J Radiol ; 91(1088): 20170655, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29848018

RESUMO

OBJECTIVE: To compare image quality of two adaptive statistical iterative reconstruction (ASiR and ASiR-V) algorithms using objective and subjective metrics for routine liver CT, with the conventional filtered back projection (FBP) reconstructions as reference standards. METHODS: This institutional review board-approved study included 52 patients with clinically suspected hepatic metastases. Patients were divided equally into ASiR and ASiR-V groups with same scan parameters. Images were reconstructed with ASiR and ASiR-V from 0 (FBP) to 100% blending percentages at 10% interval in its respective group. Mean and standard deviation of CT numbers for liver parenchyma were recorded. Two experienced radiologists reviewed all images for image quality blindly and independently. Data were statistically analyzed. RESULTS: There was no difference in CT dose index between ASiR and ASiR-V groups. As the percentage of ASiR and ASiR-V increased from 10 to 100% , image noise reduced by 8.6 -57.9% and 8.9-81.6%, respectively, compared with FBP. There was substantial interobserver agreement in image quality assessment for ASiR and ASiR-V images. Compared with FBP reconstruction, subjective image quality scores of ASiR and ASiR-V improved significantly as percentage increased from 10 to 80% for ASiR (peaked at 50% with 32.2% noise reduction) and from 10 to 90% (peaked at 60% with 51.5% noise reduction) for ASiR-V. CONCLUSION: Both ASiR and ASiR-V improved the objective and subjective image quality for routine liver CT compared with FBP. ASiR-V provided further image quality improvement with higher acceptable percentage than ASiR, and ASiR-V60% had the highest image quality score. Advances in knowledge: (1) Both ASiR and ASiR-V significantly reduce image noise compared with conventional FBP reconstruction. (2) ASiR-V with 60 blending percentage provides the highest image quality score in routine liver CT.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Anal Chem ; 90(11): 6626-6634, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29722976

RESUMO

Fluorescent probes with multimodal and multilevel imaging capabilities are highly valuable as imaging with such probes not only can obtain new layers of information but also enable cross-validation of results under different experimental conditions. In recent years, the development of genetically encoded reversibly photoswitchable fluorescent proteins (RSFPs) has greatly promoted the application of various kinds of live-cell nanoscopy approaches, including reversible saturable optical fluorescence transitions (RESOLFT) and stochastic optical fluctuation imaging (SOFI). However, these two classes of live-cell nanoscopy approaches require different optical characteristics of specific RSFPs. In this work, we developed GMars-T, a monomeric bright green RSFP which can satisfy both RESOLFT and photochromic SOFI (pcSOFI) imaging in live cells. We further generated biosensor based on bimolecular fluorescence complementation (BiFC) of GMars-T which offers high specificity and sensitivity in detecting and visualizing various protein-protein interactions (PPIs) in different subcellular compartments under physiological conditions (e.g., 37 °C) in live mammalian cells. Thus, the newly developed GMars-T can serve as both structural imaging probe with multimodal super-resolution imaging capability and functional imaging probe for reporting PPIs with high specificity and sensitivity based on its derived biosensor.

17.
Cell Physiol Biochem ; 47(2): 441-457, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29794415

RESUMO

The accumulation of mutated somatic cells due to the incompetency of body's immune system may lead to tumor onset. Therefore, enhancing the ability of the system to eliminate such cells should be the core of tumor therapy. The intrinsic antitumor immunity is triggered by tumor-specific antigens (TSA) or TSA-sensitized dendritic cells (DC). Once initiated, specific anti-tumor antibodies are produced and tumor-specific killer immune cells, including cytotoxic T lymphocytes (CTL), NK cells, and macrophages, are raised or induced. Several strategies may enhance antitumor action of immune system, such as supplying tumor-targeted antibody, activating T cells, enhancing the activity and tumor recognition of NK cells, promoting tumor-targeted phagocytosis of macrophages, and eliminating the immunosuppressive myeloid-derived suppressor cells (MDSCs) and Treg cells. Apart from the immune system, the removal of tumor burden still needs to be assisted by drugs, surgery or radiation. And the body's internal environment and tumor microenvironment should be improved to recover immune cell function and prevent tumor growth. Multiple microenvironment modulatory therapies may be applied, including addressing hypoxia and oxidative stress, correcting metabolic disorders, and controlling chronic inflammation. Finally, to cure tumor and prevent tumor recurrence, repairing or supporting therapy that consist of tissue repair and nutritional supplement should be applied properly.


Assuntos
Imunoterapia , Neoplasias/terapia , Anticorpos Antineoplásicos/uso terapêutico , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Sistema Imunitário/citologia , Sistema Imunitário/metabolismo , Células Matadoras Naturais/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Estresse Oxidativo , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral
18.
PLoS One ; 13(4): e0193714, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29641601

RESUMO

PURPOSE: To investigate the value of spectral CT in the differential diagnosis of benign from malignant pleural effusion. METHOD AND MATERIALS: 14 patients with benign pleural effusion and 15 patients with malignant pleural effusion underwent non-contrast spectral CT imaging. These patients were later verified by the combination of disease history, clinical signs and other information with the consensus of surgeons and radiologists. Various Spectral CT image parameters measured for the effusion were as follows: CT numbers of the polychromatic 140kVp images, monochromatic images at 40keV and 100keV, the material density contents from the water, fat and blood-based material decomposition images, the effective atomic number and the spectral curve slope. These values were statistically compared with t test and logistic regression analysis between benign and malignant pleural effusion. RESULTS: The CT value of benign and malignant pleural effusion in the polychromatic 140kVp images showed no differences (12.61±3.39HU vs. 14.71±5.03HU) (P>0.05), however, they were statistically different on the monochromatic images at 40keV (43.15±3.79 vs. 39.42±2.60, p = 0.005) and 100keV (9.11±1.38 vs. 6.52±2.04, p<0.001). There was difference in the effective atomic number value between the benign (7.87±0.08) and malignant pleural effusion (7.90±0.02) (P = 0.02). Using 6.32HU as the threshold for CT value measurement at 100keV, one could obtain sensitivity of 100% and specificity of 66.7% with area-under-curve of 0.843 for differentiating benign from malignant effusion. In addition, age and disease history were potential confounding factors for differentiating malignant pleural effusion from benign, since the older age (61.13±12.51 year-old vs48.57±12.33 year-old) as well as longer disease history (70.00±49.28 day vs.28.36±21.64 day) were more easily to be found in the malignant pleural effusion group than those in the benign pleural effusion group. By combining above five factors, one could obtain sensitivity of 100% and specificity of 71.4% with area-under-curve of 0.933 for differentiating benign from malignant effusion. CONCLUSION: The CT value measurement at both high and low energy levels and the effective atomic number obtained in a single spectral CT scan can assist the differential diagnosis of benign from malignant pleural effusion.Combining them with patient age and disease history can further improve diagnostic performance. CLINICAL RELEVANCE/APPLICATION: Clinical findings and Spectral CT imaging can provide significant evidences about the nature of pleural effusion.


Assuntos
Derrame Pleural Maligno/diagnóstico por imagem , Derrame Pleural/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
19.
PLoS One ; 13(3): e0194606, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29566037

RESUMO

OBJECTIVES: A number of researchers have reported that vasectomy is a risk factor for testicular cancer. However, this conclusion is inconsistent with a number of other published articles. Hence, we conducted this meta-analysis to assess whether vasectomy increases the risk of testicular cancer. MATERIALS AND METHODS: We identified all related studies by searching the PubMed, Embase, and Cochrane Library database from January 01, 1980 to June 01, 2017. The Newcastle-Ottawa Scale (NOS) checklist was used to assess all included non-randomized studies. Summarized odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the difference in outcomes between case and control groups. Subgroup analyses were performed according to the study design and country. RESULTS: A total of eight studies (2176 testicular cancer patients) were included in this systematic review and meta-analysis. Six articles were case-control studies, and two were cohort studies. The pooled estimate of the OR was 1.10 (95% CI: 0.93-1.30) based on the eight studies in a fixed effects model. Two subgroup analyses were performed according to the study design and country. The results were consistent with the overall findings. Publication bias was detected by Begg's test and Egger's test and p values > 0.05, respectively. CONCLUSIONS: Our meta-analysis suggested that there was no association between vasectomy and the development of testicular cancer. More high-quality studies are warranted to further explore the association between vasectomy and risk of testicular cancer.


Assuntos
Neoplasias Testiculares/epidemiologia , Vasectomia/estatística & dados numéricos , Estudos de Casos e Controles , Estudos de Coortes , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/etiologia , Fatores de Risco , Neoplasias Testiculares/etiologia , Vasectomia/efeitos adversos
20.
Br J Radiol ; 91(1086): 20170631, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29412008

RESUMO

OBJECTIVE: To investigate the application of low radiation and contrast dose spectral CT angiology using rapid kV-switching technique in the head and neck with subtraction method for bone removal. METHODS: This prospective study was approved by the local ethics committee. 64 cases for head and neck CT angiology were randomly divided into Groups A (n = 32) and B (n = 32). Group A underwent unenhanced CT with 100 kVp, 200 mA and contrast-enhanced CT with spectral CT mode with body mass index-dependent low dose protocols. Group B used conventional helical scanning with 120 kVp, auto mA for noise index of 12 HU (Hounsfield unit) for both the unenhanced and contrast-enhanced CT. Subtraction images were formed by subtracting the unenhanced images from enhanced images (with the 65 keV-enhanced spectral CT image in Group A). CT numbers and their standard deviations in aortic arch, carotid arteries, middle cerebral artery and air were measured in the subtraction images. The signal-to-noise ratio and contrast-to-noise ratio for the common and internal carotid arteries and middle cerebral artery were calculated. Image quality in terms of bone removal effect was evaluated by two experienced radiologists independently and blindly using a 4-point system. Radiation dose and total iodine load were recorded. Measurements were statistically compared between the two groups. RESULTS: The two groups had same demographic results. There was no difference in the CT number, signal-to-noise and contrast-to-noise ratio values for carotid arteries and middle cerebral artery in the subtraction images between the two groups (p > 0.05). However, the bone removal effect score [median (min-max)] in Group A [4 (3-4)] was rated better than in Group B [3 (2-4)] (p < 0.001), with excellent agreement between the two observers (κ > 0.80). The radiation dose in Group A (average of 2.64 mSv) was 57% lower than the 6.18 mSv in Group B (p < 0.001). The total iodine intake in Group A was 13.5g, 36% lower than the 21g in Group B. CONCLUSION: Spectral CT imaging with rapid kV-switching in the subtraction angiography in head and neck provides better bone removal with significantly reduced radiation and contrast dose compared with conventional subtraction method. Advances in knowledge: This novel method provides better bone removal with significant radiation and contrast dose reduction compared with the conventional subtraction CT, and maybe used clinically to protect the thyroid gland and ocular lenses from unnecessary high radiation.


Assuntos
Angiografia Digital/métodos , Angiografia por Tomografia Computadorizada/métodos , Cabeça/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Idoso , Aorta/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Transtornos Cerebrovasculares/diagnóstico por imagem , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação
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