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1.
J Environ Manage ; 336: 117712, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36933511

ABSTRACT

A micro firm relocation perspective plays important roles in deepening the understanding and knowledge on the environmental effects of industrial transfer and related mechanisms, however, such research and cases are currently scarce. Based on the building of both the database of firm relocation information and a conceptual framework of changes in environmental performance with firm relocation (ΔEP), involving factors of firm heterogeneity and changes in both locational conditions and whole-process pollution treatment paths, chemical firms in Jiangsu Province were selected to explore their ΔEP and related influencing mechanisms by the Wilcoxon signed-rank test of two paired samples and a binary logistic regression model in this study, respectively. Results showed that during 1998-2014, chemical firm relocation experienced a fluctuating growth trend with a continuous surge in inter-city relocation, accompanied by a deterioration in the environmental performance (EP) with a significant reduction of pollution removal intensity (p < 0.01) after firm relocation. Most firms relocated from Southern Jiangsu (72.5%) to places adjoining Jiangsu Province (58.5%), along the river and the coast (63.4%), and in the third- and fourth-tier cities (73.5%), respectively. As for these factors, the low development level of transfer-out (DTOR) and transfer-in region (DTIR) both resulted in the downgrading EP with firm relocation, but the inter-city relocation style (RS) and strict environmental regulation (ER) were the opposite. The benefits for upgrading EP after relocation conferred by the promotion of source-process treatment were limited by RS, DTOR, and DTIR. Among firms relocated to low DTIRs, the higher the firm competitiveness in terms of capital, technology, and environmental awareness, the greater the upgrading EP probability. When firms transferred to regions with stricter ER, the likelihood of improving EP increased more for those firms with weak competency. In a word, in order to prevent the pollution haven effect, superior governments should shrink regional differences in ER policies, whereas local governments in transfer-in regions should provide targeted and essential support in funding and technology according to the firm heterogeneity and fully consider actual conditions to make environmental measures in the future.


Subject(s)
Chemical Industry , Environmental Pollution , Cities , Environmental Policy , China
2.
J Sep Sci ; 43(19): 3816-3823, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32729191

ABSTRACT

Short peptide biomimetic affinity chromatography as a novel antibody separation chromatography is a potential alternative to protein A chromatography. However, if directly attaching ligand to matrix, the adsorption capacity and mass transfer rate would be affected by pore blockage and steric effect. Grafting resin is an effective method to solve this problem by using polymer as a bridge between matrix and ligand. In this work, a novel resin was prepared by grafting a tetrapeptide to the dextran-grafted matrix. Then, the adsorption properties for human immunoglobin G and BSA were determined. The results showed the saturation adsorption capacity could reach to 133 mg/g resin at pH 8.9 with a significantly low dissociation constant (0.03 mg/mL). The influence of flow rates to dynamic binding capacity of this resin was less than that of the non-grafted resin. The separation performance of the resin showed monoclonal antibody could be well isolated from the Chinese hamster ovary culture supernatant at pH 9.0 with the purity of 93.0% and yield of 84.7% by one step. Overall, this resin could achieve higher binding capacity by the possible of gaining higher ligand density, indicating its potential significance for separation in larger scale systems.


Subject(s)
Antibodies, Monoclonal/isolation & purification , Chromatography, Affinity/methods , Adsorption , Animals , Biomimetics , CHO Cells , Cricetulus , Dextrans/chemistry , Peptides/isolation & purification , Resins, Plant
3.
Biosens Bioelectron ; 134: 109-116, 2019 Jun 01.
Article in English | MEDLINE | ID: mdl-30965162

ABSTRACT

In this work, a dual-signal-amplified electrochemiluminescence (ECL) biosensor was proposed for the first time to detect microRNAs (miRNAs) based on cyclic enzyme and seeded-watermelon-like mesoporous nanospheres (mSiO2@CdTe@SiO2, mSQS NSs). mSQS NSs were successfully fabricated by inlaying the CdTe quantum dots (QDs) into the mesoporous silica (mSiO2) and future coating the surface with the silica layer. The obtained mSQS NSs contained tens of QDs and exhibited much stronger ECL signal than single QDs. The ECL biosensor achieved firstly signal amplification by using mSQS NSs to label the functional oligonucleotide probe (DNA-F) as enhanced ECL signal probes. Well-dispersed Fe3O4@Au nanoparticles were prepared as immobilization matrices to load hairpin-structured DNA probe (DNA-P). When the target miRNAs were present, hairpin DNA undertook conformation changes. Meanwhile, RNA/DNA duplexes was formed which cleaved by duplex-specific nuclease (DSN) to release miRNAs. Target miRNAs were cycled to hybridize with hairpin DNA, which achieved secondly signal amplification of the ECL biosensor. Thereafter, the complementarily parts between DNA-F and the rest DNA-P generated conjugates. The obtained conjugates would be collected on the surface of the electrode by effecting of magnet. Under the optimal conditions, the developed biosensor showed a wide linear range from 0.1 pM to 100 pM with a low detection limit of 33 fM (S/N = 3). The results of detection for the stability, specificity and reproducibility of ECL biosensor were outstanding. Simultaneously, the potential application of ECL biosensor was verified by using biosensor in serum sample.


Subject(s)
Biosensing Techniques/methods , Cadmium Compounds/chemistry , Luminescent Agents/chemistry , Luminescent Measurements/methods , MicroRNAs/blood , Quantum Dots/chemistry , Tellurium/chemistry , Electrochemical Techniques/methods , Gold/chemistry , Humans , Limit of Detection , Metal Nanoparticles/chemistry , MicroRNAs/analysis , Nanospheres/chemistry , Nanospheres/ultrastructure , Quantum Dots/ultrastructure , Silicon Dioxide/chemistry
4.
Environ Sci Pollut Res Int ; 26(8): 8098-8110, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30685864

ABSTRACT

Industrial transfer has swept through in China. However, there is still a knowledge gap about its environmental effects. In this study, industrial transfer status was assessed and evaluated by industrial ratios (%; the gross product contributions of the secondary industry to the whole industry) and the impact of such transfer on atmospheric environment (SO2, NO2, PM10 (particles with aerodynamic diameter less than 10 µm), precipitations of SO42-, NO3-, and NH4+) in the 38 districts and counties in Chongqing was analyzed and discussed for the period of 2006-2015. Results showed that industries were transferred obviously from the main urban region (MUR) into the 1-h economic region (OHER). Atmospheric sulfur and PM10 were efficiently put in control, but atmospheric nitrogen (NO2; precipitations of NO3- and NH4+) was increasing and posted a potential threat to air quality especially during 2011-2015. Correlations showed that industrial ratios had significantly positive relationships with concentrations of ambient SO2 and PM10 in the MUR and ambient NO2 in the OHER (p < 0.05) while a remarkably negative one with concentrations of ambient SO2 in the OHER (p < 0.05) during 2006-2015, implying that industrial transfer could be effective in transferring sulfur pollution but not as efficient in transferring atmospheric nitrogen and PM10 pollutions as SO2 between in the MUR and OHER. More measures should be taken to reduce nitrogen and PM10 emission and a regional monitoring network of ambient NH3 is in urgent need.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring/methods , Industry , Nitrogen Dioxide/analysis , Particulate Matter/analysis , Sulfur Dioxide/analysis , Air Movements , Air Pollution , China , Spatio-Temporal Analysis
5.
BMC Vet Res ; 14(1): 25, 2018 Jan 22.
Article in English | MEDLINE | ID: mdl-29357858

ABSTRACT

BACKGROUND: Pseudorabies (PR) is an important emerging infectious disease that is characterized by fever, extreme itching and encephalomyelitis. However, it is still unclear whether Tibetan pigs are exposed to Pseudorabies virus (PRV) or not. The present study was conducted to investigate the seroprevalence of PRV infection in Tibetan pigs in Nyingchi area of Tibet through enzyme-linked immunosorbent assay (ELISA). A total of 368 serum samples from Tibetan pigs were collected during 2015. RESULTS: Results showed that 58 (15.76%) samples were found positive for PRV antibodies with further distribution of 18.23%, 13.42% and 6.25% from Nyingchi, Mainling and Gongbo'gyamda areas on the Tibetan plateau, respectively; along with 12.10%, 17.71% and 17.57% prevalence of PRV in juveniles, sub-adults and adults, respectively. The prevalence of PRV infection between male (14.61%) and female (16.84%) showed non-significant difference (P > 0.05). The risk factors of infection were found to be associated with feed type, age and altitude. CONCLUSIONS: The present study depicts a serious concern with a new emerging infectious disease in Tibetan pigs in Tibet, China.


Subject(s)
Herpesvirus 1, Suid/immunology , Pseudorabies/epidemiology , Swine Diseases/epidemiology , Age Factors , Altitude , Animal Feed/analysis , Animals , Enzyme-Linked Immunosorbent Assay , Female , Male , Pseudorabies/immunology , Risk Factors , Seroepidemiologic Studies , Swine , Swine Diseases/virology , Tibet/epidemiology
6.
Pesqui. vet. bras ; 38(1): 37-40, Jan. 2018. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-895542

ABSTRACT

Chickens are considered to be potential reservoirs of Newcastle disease virus (NDV). In this study, six Newcastle disease virus strains were isolated and characterized in Tibetan chickens. The HN gene was sequenced, and phylogenetic relationship to reference strains was studied. The phylogenetic analysis demonstrated that these six isolated strains were closely related to NDV isolates of the reference strains GQ245823, KT002186, KU527561, KJ563939, AY225110, EU305607, KM056357, Y18898, GQ245832, AF077761 and lasota strain. Among them, EU305607, KJ563939 and KM056357 were isolated from India, while lasota strain came from attenuated vaccine widely used in China. Then, mean death time (MDT) and intracerebral pathogenicity index (ICPI) were used to estimate the pathogenicity of the isolates. Pathogenicity experiment showed HNH1 and HN17 to be virulent. Our results indicated that genetically diverse viruses circulate in Tibetan chickens, and based upon the phlogeographic analysis, we estimated the origin of ancestral viruses of the isolates and its sister strains located in India and China (lasota strain). It indicates the importance of continuous surveillance to enhance current understanding of the genetic evolution of the NDV strains.(AU)


Subject(s)
Animals , Female , Newcastle disease virus/genetics , Newcastle disease virus/pathogenicity , Chickens/virology , Phylogeny , Tibet
7.
Nucl Med Commun ; 37(3): 322-8, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26671850

ABSTRACT

Venous thromboembolism (VTE) can present as deep vein thrombosis (DVT) and/or acute pulmonary embolism (PE). In fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT, 18F-FDG activity along the deep veins of the lower extremities (LE) is often observed and, unless it is associated with focal intense activity, is not considered abnormal. However, anecdotally it has been associated with the placement of an inferior vena cava filter. In this short paper we intend to investigate this association. We found 10 patients who were investigated in the vascular laboratory by means of either LE or upper-extremity duplex or a chest computed tomography with PE protocol, or who had undergone the placement of an inferior vena cava filter between 27 April 2010 and 7 January 2013 and who had also undergone one or more 18F-FDG-PET scan(s) that included the LE. Seventeen patients without venous 18F-FDG uptake were added as controls. 18F-FDG uptake visualized in the LE was scored as the number of positive LE veins and the extent of the radiotracer uptake. The time intervals between the VTE event and the 18F-FDG-PET scan(s) were recorded. The time intervals between the most remote and the closest 18F-FDG-PET before a VTE event averaged 79 ± 101 and 49 ± 82 days, respectively, and the closest and the most remote 18F-FDG-PET after the VTE event averaged 58 ± 50 and 122 ± 124 days. The extent of uptake in the LE veins averaged 7 ± 2 for the patients with an acute DVT on LE duplex and 5 ± 3 for those with negative or chronic DVT on LE duplex (P=nonsignificant). Two patients (n=3 and 10) were negative for VTE events and had an extent of 0. The number of positive events correlated slightly with the extent of venous uptake (r=0.69). The 17 control patients without venous uptake on 18F-FDG-PET had no history of VTE. There was an association between LE venous uptake of 18F-FDG and risk for VTE. The association was not related to the location of the VTE, nor to the timing of the VTE.


Subject(s)
Fluorodeoxyglucose F18/metabolism , Lower Extremity/blood supply , Veins/metabolism , Venous Thromboembolism/diagnostic imaging , Venous Thromboembolism/metabolism , Biological Transport , Humans , Positron-Emission Tomography , Retrospective Studies , Veins/diagnostic imaging
10.
Acad Radiol ; 21(2): 232-49, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24439337

ABSTRACT

The technology behind positron emission tomography (PET) and the most widely used tracer, 2-deoxy-2-[18F]fluoro-D-glucose (FDG), were both conceived in the 1970s, but the latest decade has witnessed a rapid emergence of FDG-PET as an effective imaging technique. This is not least due to the emergence of hybrid scanners combining PET with computed tomography (PET/CT). Molecular imaging has enormous potential for advancing biological research and patient care, and FDG-PET/CT is currently the most widely used technology in this domain. In this review, we discuss contemporary applications of FDG-PET and FDG-PET/CT as well as novel developments in quantification and potential future indications including the emerging new modality PET/magnetic resonance imaging.


Subject(s)
Fluorodeoxyglucose F18/pharmacokinetics , Molecular Imaging/methods , Multimodal Imaging/methods , Positron-Emission Tomography/methods , Tomography, X-Ray Computed/methods , Humans , Radiopharmaceuticals/pharmacokinetics
11.
Clin Nucl Med ; 39(2): e173-5, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24152615

ABSTRACT

A 48-year-old man with a newly diagnosed acute myeloid leukemia developed purpuric rash on day 6 after chemotherapy. Skin biopsy on day 8 demonstrated Grover disease. Triamcinolone treatment started on day 10 with subjective improvement on day 15. Initial FDG PET/CT on day 12 demonstrated rarely seen diffuse skin uptake that was interpreted as technical artifact and repeated on day 16. Accurately reviewing both PET and CT imaging would prevent confusion between diffuse cutaneous hypermetabolic activity and a technical artifact. Grover disease usually affects the trunk and may be related to the elimination of chemotherapy agents by sweating.


Subject(s)
Acantholysis/complications , Acantholysis/diagnosis , Fluorodeoxyglucose F18 , Ichthyosis/complications , Ichthyosis/diagnosis , Leukemia, Myeloid, Acute/complications , Multimodal Imaging , Positron-Emission Tomography , Tomography, X-Ray Computed , Acantholysis/diagnostic imaging , Humans , Ichthyosis/diagnostic imaging , Male , Middle Aged
12.
Hell J Nucl Med ; 16(3): 169-74, 2013.
Article in English | MEDLINE | ID: mdl-24137579

ABSTRACT

Our purpose was to evaluate quantitative mid-treatment fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT scans in predicting the quantitative result of the end of treatment 18F-FDG PET/CT scan. With approval of Emory's Institutional Review Board, data were extracted from 273 existing 18F-FDG PET/CT scans of 143 pediatric patients performed for evaluation of lymphoma. The inclusion criteria were the availability of an initial staging scan (D0) and a mid-treatment scan after 1 to 3 cycles of chemotherapy (D1) and a post-treatment scan (D2). Absolute and relative changed of D1 compared to D0 were measured and their values in predicting D3 values were determined. Analysis was performed on a lesion basis (N=78) in 18 patients with an average of 4.3 lesions per patients. Results showed that the predictive value depended on the value selected as significant for the predictors (D1 SUV and D1 %SUV), and on the limit between negative and positive selected for the predicted value D2 SUV. If the maximum SUV<2.0 in D2 was the limit for negative, the negative predictive value if D1<4 was 0.84%. If positive was defined as D2>3.0, the positive predictive value of D1>4 was 100%. In that way outcome was predictable with absolute certainty in as many as 71% of the lesions with a single limit for D1 and D2. In conclusion, in this limited retrospective study the positive predictive value of the mid-treatment scan, was high for the post-treatment result for patient and lesion response seen on D2.


Subject(s)
Antineoplastic Agents/therapeutic use , Fluorodeoxyglucose F18 , Lymphoma/diagnosis , Lymphoma/drug therapy , Multimodal Imaging/statistics & numerical data , Positron-Emission Tomography/statistics & numerical data , Tomography, X-Ray Computed/statistics & numerical data , Adolescent , Child , Female , Humans , Image Interpretation, Computer-Assisted/methods , Lymphoma/epidemiology , Male , Prevalence , Prognosis , Radiopharmaceuticals , Reproducibility of Results , Retrospective Studies , Risk Factors , Sensitivity and Specificity , Treatment Outcome
14.
BMC Genomics ; 11: 729, 2010 Dec 30.
Article in English | MEDLINE | ID: mdl-21192789

ABSTRACT

BACKGROUND: Salmonella paratyphi C is one of the few human-adapted pathogens along with S. typhi, S. paratyphi A and S. paratyphi B that cause typhoid, but it is not clear whether these bacteria cause the disease by the same or different pathogenic mechanisms. Notably, these typhoid agents have distinct sets of large genomic insertions, which may encode different pathogenicity factors. Previously we identified a novel prophage, SPC-P1, in S. paratyphi C RKS4594 and wondered whether it might be involved in pathogenicity of the bacteria. RESULTS: We analyzed the sequence of SPC-P1 and found that it is an inducible phage with an overall G+C content of 47.24%, similar to that of most Salmonella phages such as P22 and ST64T but significantly lower than the 52.16% average of the RKS4594 chromosome. Electron microscopy showed short-tailed phage particles very similar to the lambdoid phage CUS-3. To evaluate its roles in pathogenicity, we lysogenized S. paratyphi C strain CN13/87, which did not have this prophage, and infected mice with the lysogenized CN13/87. Compared to the phage-free wild type CN13/87, the lysogenized CN13/87 exhibited significantly increased virulence and caused multi-organ damages in mice at considerably lower infection doses. CONCLUSIONS: SPC-P1 contributes pathogenicity to S. paratyphi C in animal infection models, so it is possible that this prophage is involved in typhoid pathogenesis in humans. Genetic and functional analyses of SPC-P1 may facilitate the study of pathogenic evolution of the extant typhoid agents, providing particular help in elucidating the pathogenic determinants of the typhoid agents.


Subject(s)
Bacteriophage P1/genetics , Prophages/genetics , Salmonella paratyphi C/pathogenicity , Salmonella paratyphi C/virology , Animals , Bacteriophage P1/ultrastructure , Colony Count, Microbial , DNA, Viral/genetics , Genome, Bacterial/genetics , Humans , Lysogeny/genetics , Mice , Molecular Sequence Data , Open Reading Frames/genetics , Paratyphoid Fever/genetics , Paratyphoid Fever/microbiology , Paratyphoid Fever/pathology , Phylogeny , Polymerase Chain Reaction , Prophages/ultrastructure , Salmonella paratyphi C/classification , Salmonella paratyphi C/growth & development , Serotyping , Virus Activation/genetics
15.
Proc Am Thorac Soc ; 4(4): 347-9, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17652499

ABSTRACT

Medical imaging has increasingly provided surrogate endpoints in therapeutic trials. This use assumes that the interpretation of the images can be unbiased and reproducible and that the image attributes included in the interpretation are relevant to the mechanism of the trial. The principal motivation for computer analysis is to evaluate an attribute of the image as a metric in an algorithmic manner, independent of observer bias or variability. The metric is expected to reflect change in rough proportion with at least one aspect of the degree of disease or the effectiveness of the therapeutic intervention. If either condition is satisfied, the measure is quantitative. Visual interpretation explicitly or implicitly tends to be based on multiple image attributes. Explicit combination of multiple attributes yields composite scores. To evaluate the risk or probability of disease, they are useful. But the components of the scores can be combined only if they are mathematically isomorphic. For the evaluation of interventions, they are less useful because the effect on one component may be obscured by the lack of effect on other components. This article reviews quantification of air trapping in cystic fibrosis and quantification in general. Validation of any computer analysis can rely on agreement with visual interpreters (on average), they can be derived from first principles, or by agreement with an alternative method that measures the pathophysiological mechanism directly (xenon washout for air trapping). However, in the context of trials, the validation may come from a superior ability to detect objective change and to discriminate between affected and unaffected individuals.


Subject(s)
Cystic Fibrosis/diagnosis , Diagnosis, Computer-Assisted , Diagnostic Imaging , Algorithms , Humans
16.
Cancer Biother Radiopharm ; 21(3): 243-56, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16918301

ABSTRACT

PURPOSE: The primary aim of this study was to evaluate the biodistribution and toxicity of 131I-chimeric(ch) TNT-1/B monoclonal antibody (MAB), which binds to intracellular antigens of necrotic regions within tumors, in patients with advanced colon or colorectal cancer. The rationale for targeting areas of tumor necrosis is the observation that necrotic lesions are more abundant in cancer lesions than in surrounding tissues. PATIENTS AND METHODS: Cohorts of patients with advanced colon or colorectal cancer were administered a one-time 30-60-minute intravenous (i.v.) infusion of 131I-chTNT-1/B at doses ranging from 12.95 to 66.23 MBq/kg (0.35-1.79 mCi/kg). RESULTS: The dose-limiting toxicity, experienced at 66.23 MBq/kg (1.79 mCi/kg) 131I-chTNT-1/B MAB, was myelosuppression. Two (2) patients at the 66.23-MBq/kg (1.79 mCi/kg) dose level had both grade 3 thrombocytopenia and grade 3 neutropenia that persisted for at least 2 weeks but were reversible. The maximum tolerated dose was 58.09 MBq/kg (1.57 mCi/kg) 131I-chTNT-1/B MAB. Of the 21 patients, one developed a moderate human antichimeric antibody (HACA) response and 6 developed low HACA responses. CONCLUSIONS: The infusion of 131I-chTNT-1/B MAB was well tolerated, without significant nonhematological toxicity. No patient obtained a complete or partial response, based on tumor cross-product response criteria. Tumor localization was seen in patients with dose levels at, and exceeding, 50.23 MBq/kg (1.36 mCi/kg) 131I-chTNT-1/B MAB.


Subject(s)
Antibodies, Monoclonal/chemistry , Colonic Neoplasms/radiotherapy , Colorectal Neoplasms/radiotherapy , Iodine Radioisotopes/therapeutic use , Radioimmunotherapy/instrumentation , Radioimmunotherapy/methods , Adult , Aged , Clinical Trials as Topic , Female , Humans , Male , Middle Aged , Necrosis , Radiometry , Recombinant Fusion Proteins/chemistry , Tomography, Emission-Computed, Single-Photon/methods , Tumor Necrosis Factor-alpha/metabolism
17.
Chest ; 128(4): 2327-35, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16236891

ABSTRACT

PURPOSES: To evaluate quantitative air trapping measurements in children with mild cystic fibrosis (CF) lung disease during a 1-year, double-blind, placebo-controlled, recombinant human deoxyribonuclease (rhDNase) [dornase alfa] intervention trial and compare results from quantitative air trapping with those from spirometry or visually scored high-resolution CT (HRCT) scans of the chest. MATERIALS AND METHODS: Twenty-five children with CF randomized to either daily rhDNase or placebo aerosol were evaluated at baseline, and at 3 months and 12 months by spirometer-triggered HRCT and spirometry. Outcome variables were percentage of predicted FVC, FEV1, and forced expiratory flow, midexpiratory phase (FEF(25-75%)); total and subcomponent visual HRCT scores; and quantitative air trapping measurements derived from chest HRCT images. RESULTS: At baseline, there were no statistical differences between groups in any of the variables used as an outcome. After 3 months of treatment, both groups had improvements in percentage of predicted FEV1 and FEF(25-75%), and total HRCT visual scores. In contrast, the rhDNase group had a 13% decrease in quantitative air trapping from baseline (severe air trapping [A3]), compared to an increase of 48% in the placebo group (p = 0.023). After 12 months, both groups had declines in percentage of predicted FVC and FEV1, but the rhDNase group retained improvements in percentage of predicted FEF(25-75%) and quantitative air trapping. The mucus plugging and total HRCT visual scores were also improved in the rhDNase group after 12 months of treatment, with and without significant differences between groups (p = 0.026 and p = 0.676). Quantitative air trapping (A3) remained improved in the rhDNase group (- 15.4%) and worsened in the placebo group (+61.3%) with nearly significant differences noted between groups (p = 0.053) after 12 months of treatment. CONCLUSIONS: Quantitative air trapping is a more consistent sensitive outcome measure than either spirometry or total HRCT scores, and can discriminate differences in treatment effects in children with minimal CF lung disease.


Subject(s)
Air/analysis , Cystic Fibrosis/drug therapy , Deoxyribonuclease I/therapeutic use , Child , Cystic Fibrosis/diagnostic imaging , Cystic Fibrosis/physiopathology , Double-Blind Method , Humans , Placebos , Respiratory Function Tests , Tomography, X-Ray Computed
18.
Chest ; 123(5): 1655-63, 2003 May.
Article in English | MEDLINE | ID: mdl-12740287

ABSTRACT

PURPOSE: To automatically derive the degree of air trapping in mild cystic fibrosis (CF) disease from high-resolution CT (HRCT) data, and to evaluate the discriminating power of the measurement. MATERIALS AND METHODS: The data consist of six pairs of anatomically matched tomographic slices, obtained during breath-holding in triggered HRCT acquisitions. The pairs consist of an inspiratory slice, at > or = 95% of slow vital capacity, and an expiratory slice at near residual volume (nRV). The subjects are 25 patients with mild CF and 10 age-matched, normal control subjects. SUBJECTS: Lung segmentation is automatic. The limits defining air trapping in the expiratory slices are determined by the distribution of densities in the expanded lung. They are modulated by density changes between expiration and inspiration. Air trapping defects consist of contiguous low-density voxels. The difference between patients and control subjects was evaluated in comparison to pulmonary function test (PFT) results and lung density distribution descriptors (global density descriptors). RESULTS: In mild CF, air trapping does not correlate with global PFT results, except for the ratio of residual volume (RV) to total lung capacity (TLC); however, the size of air trapping defects was the best discriminator between patients and control subjects (p < 0.005). Of PFT results, only RV/TLC reached significance at p < 0.05. The global density descriptors reached near significance in the nRV images only. CONCLUSION: Air trapping defined as defect size and measured in an objective automated manner is a powerful discriminator for mild CF.


Subject(s)
Cystic Fibrosis/diagnostic imaging , Lung/diagnostic imaging , Tomography, X-Ray Computed , Adolescent , Child , Cystic Fibrosis/physiopathology , Female , Forced Expiratory Volume , Humans , Image Processing, Computer-Assisted , Male , Maximal Midexpiratory Flow Rate , Residual Volume , Spirometry , Vital Capacity
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