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Objective:Both antibiotic resistant bacteria (ARBs) and antibiotic resistant genes (ARGs) are considered as one of the most dangerous environmental pollutants in the 21st century by the WHO. This study aims to understand the ARGs of Klebsiella pneumoniae (K. pneumoniae) with multiple drug resistance bacterium from the marine water collected from a beach at Sanya Bay, and to explore the antibiotic resistance mechanism of the K. pneumoniae, providing a basis for exploring the transfer of drug resistance genes of beach, and preventing and controlling the health risk of entertainment population.Methods:The sample of marine water were collected and screened by Mcconkey plate. The drug sensitive test was detected by Merieux VITEK2, The DNA was extracted and one strain of 16srDNA was sequenced and identified as K. pneumoniae. Whole-genome resequencing was performed using Illumina HiseqXten platform, and the obtained sequences were compared with NCBI blasting. The reference bacterium were multi-resistant K. pneumoniae HS11286. Plasmids were extracted and the resistant genes were identified.Results:The ARGs encoding protein was 117/4801 (identity > 40%) and the carrying rate was 2.436 9%. The identity of following ARGs of OKPB, sul1, rpoB, ef-tu, phoP, sul2, AAC(6’)-ib-cr, QnrB, floR, aadA16 were more than 99%. The strain showed resistance to ampicillin, ticacillin/clavulanic acid and chloramphenicol, and was intermediate to ampicillin/sulbactam, compound sulfamethoxazole, ciprofloxacin, minocycline. Preliminary positioning showed that Qnrs, sul1, tetA, cat, QacE were carried on plasmid.Conclusion:The multiple drug resistant bacteria strain has a variety of different resistant phenotypes, some ARGs can be easily spread by plasmid. It probably will bring exposure risk to people for entertainment. Sensibility of some antibiotics were on the brink of resistance, It is necessary to tracking corresponding antibiotics pollution and strengthening monitoring of ARBs and mobile resistant elements of bacteria.
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Objective:With the increasing attention to health influence by ecology environment and climate changes, it is important to explore the characters of drinking water quality and meteorological factors at tropical areas of South China. This study aims to study the water quality of municipal source water and to elucidate the relationship between water quality changes and climatic factors at Haikou.Methods:By analyzing the data of water quality indexes of source water in the past five years from July 2013 to April 2017, the representative indexes as following were analyzed: Fecal coliforms (FC), ammonia nitrogen (NH4Results:Only the CODConclusion:The source water has a higher concentration of iron. The temperature is an important factor that affects the local source water quality of Haikou. It is necessary to strengthen removing COD
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Objective To investigate the effect of resveratrol on the expression of peroxisome proliferator activated re-ceptor γ coactivator-1α(PGC-1α)in skeletal muscle of rats with chronic obstructive pulmonary disease(COPD). Methods A total of 45 male Sprague Dawley rats were randomly divided into control group,model group and resveratrol group,15 rats in each group. The rats in the model group and resveratrol group were made COPD model through the intratracheal instillation of lipopolysaccharide and repeated smoke exposure,except the rats in the control group. From the 29th day of smoke exposure,the rats in the control group and model group were given 2 mL saline by gavage,once a day for 30 days;and the rats in the resvera-trol group were given 2 mL resveratrol solution by gavage(100 mg·kg - 1 ·d - 1 ),once a day for 30 days. After 30 days of con-tinuous gavage,the rats were sacrificed,then arterial blood and skeletal muscles were harvested. The level of tumor necrosis factor-α(TNF-α)in serum and skeletal muscle of rats was detected by enzyme linked immunosorbent assay. The expression of PGC-1α,nuclear respiratory factor 1(NRF1),mitochondrial transcription factor A(Tfam)and cytochrome C oxidase Ⅳ(COXⅣ)mRNA in skeletal muscle tissues of rats was determined by quantitative real-time polymerase chain reaction. The expres-sion of PGC-1α,NRF1,Tfam and COX Ⅳ protein was detected by Western blot. Results The level of TNF-α in serum and skeletal muscle tissues of rats in the model group and resveratrol group was significantly higher than that in the control group (P < 0. 01). The level of TNF-α in serum and skeletal muscle tissues of rats in the resveratrol group was significantly lower than that in the model group(P < 0. 01). The expression of PGC-1α,NRF1,Tfam,COX Ⅳ protein and mRNA in skeletal mus-cle tissues of rats in the resveratrol group and model group was significantly lower than that in the control group(P < 0. 01). The expression of PGC-1α,NRF1,Tfam,COX Ⅳ protein and mRNA in skeletal muscle tissues of rats in the resveratrol group was significantly higher than that in the model group(P < 0. 01,P < 0. 05). Conclusion Resveratrol can reduce the level of TNF-α in serum and skeletal muscle tissues of COPD rats,increase the expression of PGC-1α,thereby improving the mitochon-drial biosynthesis function.
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Bone marrow mesenchymal stem cells (MSCs) transplantation could repair injury tissue, but no study confirms whether MSCs can promote the proliferation of endogenous lung stem cells to repair alveolar epithelial cells of mice with chronic obstructive pulmonary disease (COPD). This study was designed to investigate the effect of MSCs on the proliferation of endogenous lung stem cells in COPD mice to confirm the repair mechanism of MSCs. The mice were divided into control group, COPD group, and COPD+MSCs group. The following indexes were detected: HE staining of lung tissue, the mean linear intercept (MLI) and alveolar destructive index (DI), the total cell number in bronchoalveolar lavage fluid (BALF), pulmonary function, alveolar wall apoptosis index (AI) and proliferation index (PI), the number of CD45(-)/CD31(-)/Sca-1(+) cells by flow cytometry (FCM), and the number of bronchoalveolar stem cells (BASCs) in bronchoalveolar duct junction (BADJ) by immunofluorescence. As compared with control group, the number of inflammatory cells in lung tissue was increased, alveolar septa was destroyed and the emphysema-like changes were seen, and the changes of lung function were in line with COPD in COPD group; AI of alveolar wall was significantly increased and PI significantly decreased in COPD group. There was no significant difference in the number of CD45(-)/CD31(-)/Sca-1(+) cells and BASCs between control group and COPD group. As compared with COPD group, the number of inflammatory cells in BALF was decreased, the number of CD45(-)/CD31(-)/Sca-1(+) cells and BASCs was increased, AI of alveolar wall was decreased and PI was increased, and emphysema-like changes were relieved in COPD+MSCs group. These findings suggested that MSCs transplantation can relieve lung injury by promoting proliferation of endogenous lung stem cells in the cigarette smoke-induced COPD mice.
Subject(s)
Animals , Mice , Cell Proliferation , Lung , Pathology , Mesenchymal Stem Cells , Cell Biology , Mice, Inbred C57BL , Pulmonary Disease, Chronic Obstructive , Pathology , TherapeuticsABSTRACT
Airway remodeling is an important pathological feature of asthma and the basis of severe asthma. Proliferation of airway smooth muscle cells (ASMCs) is a major contributor to airway remodeling. As an important Ca(2+) channel, transient receptor potential vanilloid 1 (TRPV1) plays the key role in the cell pathological and physiological processes. This study investigated the expression and activity of TRPV1 channel, and further clarified the effect of TRPV1 channel on the ASMCs proliferation and apoptosis in order to provide the scientific basis to treat asthmatic airway remodeling in clinical practice. Immunofluorescence staining and reverse transcription polymerase chain reaction (RT-PCR) were used to detect the expression of TRPV1 in rat ASMCs. Intracellular Ca(2+) was detected using the single cell confocal fluorescence microscopy measurement loaded with Fluo-4/AM. The cell cycles were observed by flow cytometry. MTT assay and Hoechst 33258 staining were used to detect the proliferation and apoptosis of ASMCs in rats respectively. The data showed that: (1) TRPV1 channel was present in rat ASMCs. (2) TRPV1 channel agonist, capsaicin, increased the Ca(2+) influx in a concentration-dependent manner (EC50=284.3±58 nmol/L). TRPV1 channel antagonist, capsazepine, inhibited Ca(2+) influx in rat ASMCs. (3) Capsaicin significantly increased the percentage of S+G2M ASMCs and the absorbance of MTT assay. Capsazepine had the opposite effect. (4) Capsaicin significantly inhibited the apoptosis, whereas capsazepine had the opposite effect. These results suggest that TRPV1 is present and mediates Ca(2+) influx in rat ASMCs. TRPV1 activity stimulates proliferation of ASMCs in rats.
Subject(s)
Animals , Rats , Antipruritics , Pharmacology , Apoptosis , Physiology , Bronchi , Cell Biology , Metabolism , Calcium Signaling , Physiology , Capsaicin , Pharmacology , Cell Proliferation , Myocytes, Smooth Muscle , Cell Biology , Metabolism , Rats, Sprague-Dawley , TRPV Cation Channels , MetabolismABSTRACT
Airway remodeling is an important pathological feature of asthma and the basis of severe asthma. Proliferation of airway smooth muscle cells (ASMCs) is a major contributor to airway remodeling. As an important Ca(2+) channel, transient receptor potential vanilloid 1 (TRPV1) plays the key role in the cell pathological and physiological processes. This study investigated the expression and activity of TRPV1 channel, and further clarified the effect of TRPV1 channel on the ASMCs proliferation and apoptosis in order to provide the scientific basis to treat asthmatic airway remodeling in clinical practice. Immunofluorescence staining and reverse transcription polymerase chain reaction (RT-PCR) were used to detect the expression of TRPV1 in rat ASMCs. Intracellular Ca(2+) was detected using the single cell confocal fluorescence microscopy measurement loaded with Fluo-4/AM. The cell cycles were observed by flow cytometry. MTT assay and Hoechst 33258 staining were used to detect the proliferation and apoptosis of ASMCs in rats respectively. The data showed that: (1) TRPV1 channel was present in rat ASMCs. (2) TRPV1 channel agonist, capsaicin, increased the Ca(2+) influx in a concentration-dependent manner (EC50=284.3±58 nmol/L). TRPV1 channel antagonist, capsazepine, inhibited Ca(2+) influx in rat ASMCs. (3) Capsaicin significantly increased the percentage of S+G2M ASMCs and the absorbance of MTT assay. Capsazepine had the opposite effect. (4) Capsaicin significantly inhibited the apoptosis, whereas capsazepine had the opposite effect. These results suggest that TRPV1 is present and mediates Ca(2+) influx in rat ASMCs. TRPV1 activity stimulates proliferation of ASMCs in rats.
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Bronchial asthma is a common chronic airway inflammatory disease. Asthma is associated with high mortality, especially in the elderly patients. Repeated exacerbations cause disease progression. Therefore, identifying the onset of acute elderly asthma as soon as possible and giving the effective treatment is crucial to improve the prognosis. This study was to investigate the significance of fractional exhaled nitric oxide (FeNO) combined with serum procalcitonin (PCT) and C-reactive protein (CRP) in the evaluation of elderly asthma. A total of 120 elderly patients with an acute attack of asthma from July, 2010 to May, 2012 were studied. On presentation, FeNO, serum PCT and CRP concentrations were measured and sputum culture was also performed. The elderly patients were re-evaluated when they had returned to their stable clinical state. The elderly patients were classified into two groups: positive bacterial culture group (A) and negative bacterial culture group (B). The results showed that: (1) In patients with an acute exacerbation of asthma, 48 (40%) patients had positive sputum bacterial culture and 72 (60%) had negative sputum bacterial culture. (2) The levels of FeNO in patients with acute exacerbation of asthma were significantly higher than in those with no acute exacerbation state (63.8±24.6 vs. 19±6.5 ppb, P0.05). (3) The levels of PCT and CRP in group A patients with an acute exacerbation of asthma were significantly higher (P0.05) when compared with the exacerbation group. There were no significant differences in the levels of PCT and CRP between the two groups in non-acute exacerbation state (P>0.05). These results suggest that the increase in FeNO indicates the acute exacerbation of asthma, and the elevation of serum PCT and CRP levels may be associated with bacterial infection.
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Bronchial asthma is a common chronic airway inflammatory disease. Asthma is associated with high mortality, especially in the elderly patients. Repeated exacerbations cause disease progression. Therefore, identifying the onset of acute elderly asthma as soon as possible and giving the effective treatment is crucial to improve the prognosis. This study was to investigate the significance of fractional exhaled nitric oxide (FeNO) combined with serum procalcitonin (PCT) and C-reactive protein (CRP) in the evaluation of elderly asthma. A total of 120 elderly patients with an acute attack of asthma from July, 2010 to May, 2012 were studied. On presentation, FeNO, serum PCT and CRP concentrations were measured and sputum culture was also performed. The elderly patients were re-evaluated when they had returned to their stable clinical state. The elderly patients were classified into two groups: positive bacterial culture group (A) and negative bacterial culture group (B). The results showed that: (1) In patients with an acute exacerbation of asthma, 48 (40%) patients had positive sputum bacterial culture and 72 (60%) had negative sputum bacterial culture. (2) The levels of FeNO in patients with acute exacerbation of asthma were significantly higher than in those with no acute exacerbation state (63.8±24.6 vs. 19±6.5 ppb, P<0.05). There was no significant difference in FeNO between group A and group B (P>0.05). (3) The levels of PCT and CRP in group A patients with an acute exacerbation of asthma were significantly higher (P<0.05) than in group B (for PCT: 27.46±9.32 vs. 7.85±3.52 ng/mL; for CRP: 51.25±11.46 vs. 17.11±5.87 mg/L, respectively). When they had returned to stable clinical state, the levels of PCT and CRP in group A were decreased significantly (P<0.05), and those in group B had no significant change (P>0.05) when compared with the exacerbation group. There were no significant differences in the levels of PCT and CRP between the two groups in non-acute exacerbation state (P>0.05). These results suggest that the increase in FeNO indicates the acute exacerbation of asthma, and the elevation of serum PCT and CRP levels may be associated with bacterial infection.
Subject(s)
Aged , Female , Humans , Male , Asthma , Diagnosis , Metabolism , Biomarkers , Metabolism , Breath Tests , Methods , C-Reactive Protein , Metabolism , Calcitonin , Blood , Calcitonin Gene-Related Peptide , Exhalation , Nitric Oxide , Metabolism , Protein Precursors , Blood , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Objective To discuss the molecular mechanism of 18F-fluorodeoxyglucose (FDG) uptake in tumor and to assess its value to identify pathologic type and cancer staging in patients with earlystage nasopharyngeal carcinoma.Methods Forty patients with nasopharyngeal carcinoma of early-stage,including 12 cases with T1 stage and 28 cases with T2 stage, underwent FDG PET imaging.The maximum standardized uptake value ( SUVmax ) and mean standardized uptake value ( SUVmean ) of FDG uptake of each patient were measured and compared between T1 and T2 stage by t-test.The expression of glucose transport protein 1 ( Glut1 ) and hexokinase- Ⅱ ( HK- Ⅱ ) of each case was measured in paraffin sections by streptavidin-perosidase (SP) immunohistochemistry.The positive expression rate of Glut1 and HK- Ⅱ was calculated and compared between T1 and T2 by x2 test.Meanwhile, the correlation between the expression of Glut1 or HK-Ⅱ and the SUVmax was tested by Pearson analysis.Results The SUVmax and SUVmean in 40 patients were 9.45 ± 1.87 and 6.04 ± 1.09, respectively.The SUVmax of patients with T1 stage (8.95 ± 1.91 ) was significantly lower (t =4.46, P＜0.001 ) than that of patients with T2 stage (11.55 ± 1.70), and the SUVmean of patients with T1 stage (5.61 ± 1.08) was significantly lower ( t = 6.76, P ＜ 0.001 ) than that of patients with T2 stage (7.98 ± 1.10) too.Among 40 patients, all patients showed positive expression of Glut1 and HK-Ⅱ , and the positive expression rate of Glut1 and HK-Ⅱ was ( 45.2 ± 10.9 )% and ( 68.3 ±9.5)%, respectively.The positive expression rate of Glut1 was (38.4 ±8.1)% in T1 stage and (49.7 ±12.6)% in T2 stage, which displayed no difference (x2 =40.58, P＞0.05), but the HK-Ⅱ positive expression rate showed significant difference (x2 =58.71, P＜0.05) between T1 stage (60.1 ±11.1)% and T2 stage (77.9 ± 14.7 )%.The correlation analysis indicated that there was low-degree positive correlation (r =0.369, P=0.019) between the SUVmax and Glut1 expression, and there was medium-degree positive correlation (r = 0.549, P = 0.001 ) between the SUVmax and HK-Ⅱ expression.Conclusion Expression of Glut1 and HK-Ⅱ was positively correlated with FDG uptake in patients with early-stage nasopharyngeal carcinoma.
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<p><b>OBJECTIVE</b>To evaluate the in vivo and in vitro stability of (131)I-Herceptin and its form of existence in the blood.</p><p><b>METHODS</b>Herceptin was labelled with iodine-131 using the Iodogen method. (131)I-Herceptin was stored at 4 degrees celsius for 3, 24, 48, 72 and 96 h, and the radiochemical purity (RCP) was measured by high performance liquid chromatography (HPLC). Five rabbits received injections of (131)I-Herceptin and at 1, 3, 6, 24, 48, 72, 96 and 120 h after the injection, blood samples were taken to measure the RCP of (131)I-Herceptin in the serum, and the radio count of the serum and blood cells was calculated.</p><p><b>RESULTS</b>The baseline RCP of (131)I-Herceptin was (94.9±2.7)%. The RCP was stable after placement at 4 degrees celsius for not over 72 h (F=15.985, P<0.001), but was significantly lowered to (82.6±2.8)% after preservation for over 72 h (t=9.971, P<0.001). Within the time of 1.0 to 96 h after injection in rabbits, (131)I-Herceptin existed mainly in the serum with a radio count of 81%-87%; 24 h after the injection, the RCP of (131)I-Herceptin in the serum was significantly lowered to (75.4±3.9)% (t=6.564, P<0.001).</p><p><b>CONCLUSION</b>Storage at 4 degrees celsius for no more than 72 h does not obviously affect the activity of (131)I-Herceptin in terms of RCP. After injection in rabbits, (131)I-Herceptin exists mainly in the serum and its radiochemical purity remains stable within 24 h, after which obvious degradation occurs.</p>
Subject(s)
Animals , Humans , Rabbits , Antibodies, Monoclonal, Humanized , Pharmacokinetics , Blood , Metabolism , Cell Line, Tumor , Drug Stability , Iodine Radioisotopes , Pharmacokinetics , Radiopharmaceuticals , Pharmacokinetics , TrastuzumabABSTRACT
<p><b>OBJECTIVE</b>To investigate the relationship between the proliferation of sensitized human airway smooth muscle cells (HASMCs) and the expression of extracellular signal regulated kinase (ERK) and the effect of Shenmai Injection (SMI) on HASMCs.</p><p><b>METHODS</b>The HASMCs cultured in vitro were divided into three groups: (1) control group; (2) sensitized group: containing 10% asthmatic serum; (3) SMI group: further divided into three different concentration subgroups interferred with 10 microL/mL, 50 microL/mL, and 100 microL/mL SMI, respectively. The proliferation of HASMCs was detected using MTT method, the expression of proliferating cell nucleus antigen (PCNA) in HASMCs was detected using immunocytochemical staining, and the expression of phosphoration-ERK1/2 (p-ERK1/2) protein was detected using Western-blot.</p><p><b>RESULTS</b>After passive sensitization,: the optical density value (A A(490) value) of HASMCs was significantly increased from 0.366+/-0.086 to 0.839+/- 0.168 (P<0.05). In addition, the expression of PCNA was significantly increased from 28.7%+/-5.9% in the control group to 69.8%+/-7.5% in the sensitized group (P<0.05). At the same time, the expression of p-ERK1/2 in passively sensitized HASMCs was significantly increased compared with the control group (all P<0.05). After application of 10 microL/mL, 50 microL/mL, and 100 microL/mL SMI to the cultured media of passively sensitized group, the A(570) value was significantly decreased from 0.839+/-0.168 to 0.612+/-0.100, 0.412+/-0.092, and 0.339+/-0.077, respectively (P<0.05). Moreover, the expression of PCNA was significantly decreased from 69.8%+/-7.5% to 57.8%+/-6.2%, 40.7%+/-5.4%, and 26.1%+/-5.2%, respectively. At the same time, the expression of p-ERK1/2 in each SMI group was significantly decreased compared with the sensitized group (all P<0.05).</p><p><b>CONCLUSION</b>ERK signal transduction pathway may be involved in the airway remodeling in asthma. The expression of ERK can be inhibited by SMI in a dose-dependent manner, thus preventing the proliferation of HASMCs.</p>
Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Asthma , Pathology , Blotting, Western , Cell Proliferation , Drug Combinations , Drugs, Chinese Herbal , Pharmacology , Extracellular Signal-Regulated MAP Kinases , Metabolism , Injections , Myocytes, Smooth Muscle , Pathology , Proliferating Cell Nuclear Antigen , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To analyze the radiogenic distribution in the sacrum in whole-body bone scanning.</p><p><b>METHODS</b>A total of 212 patients receiving whole-body bone scanning without any explicit bone metastases were divided into different age and gender groups. The radioactive distribution in the sacrum in whole-body bone scanning was analyzed statistically.</p><p><b>RESULTS</b>Of these cases, 31.1% presented with thin radioactive distribution in the sacrum and 11.3% exhibited increased radioactive distribution. Normal radioactive distribution in the sacrum was found in 57.6% of the cases. In both male and female elderly patients (>70 years), the rate of normal radioactive distribution in the sacrum was obviously reduced with increased rate of thin radioactive distribution. The female elderly patients showed higher rate of increased radioactive distribution in the sacrum than male elderly patients.</p><p><b>CONCLUSION</b>The radioactive distribution in the sacrum is similar between female and male patients. Elderly male patients over 70 years have generally thin radioactive distribution in the sacrum due to the presence of osteoporosis, which is also associated with latent fracture of the sacrum to result in increased radioactive distribution in the sacrum in whole-body bone scanning.</p>
Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Neoplasms , Diagnostic Imaging , Pathology , Radionuclide Imaging , Sacrum , Diagnostic Imaging , Spinal Neoplasms , Diagnostic Imaging , Technetium Tc 99m Medronate , Pharmacokinetics , Whole Body ImagingABSTRACT
<p><b>OBJECTIVE</b>To study the overexpression of vascular endothelial growth factor (VEGF) and fluorine-18 fluorodeoxyglucose (FDG) uptake in early-stage nasopharyngeal carcinoma (NPC) and evaluate their relationship.</p><p><b>METHODS</b>FDG positron emission tomography (PET) was performed in forty patients with stage I and stage II NPC. The maximum and mean standard uptake values (SUVmax and SUVmean, respectively) were measured in each patient, and the expression of VEGF was measured on paraffin sections using immunohistochemistry.</p><p><b>RESULTS</b>The FDG uptake in the patients were 9.45-/+1.87 (SUVmax) and 6.04-/+1.09 (SUVmean), 8.95-/+1.91 (SUVmax) and 6.04-/+1.09 (SUVmean) in stage I patients, and 11.55-/+1.70 (SUVmax) and 7.98-/+1.1 (SUVmean) in stage II patients. The FDG uptake of stage II patients was higher than that of stage I patients. The FDG uptake of non-keratinizing differentiated carcinoma was 9.74-/+1.82 (SUVmax) and 6.82-/+1.23 (SUVmean) and 10.44-/+2.16 (SUVmax) and 6.68-/+1.35 (SUVmean) in non-keratinizing undifferentiated carcinoma, showing no significant differences between them (SUVmax: t=1.230, P>0.05; SUVmean: t=0.346, P>0.05). The VEGF-positive cells were 60.80% in the tumor. A correlation between VEGF expression and FDG uptake in he tumor was noted (r=0.460, P=0.03).</p><p><b>CONCLUSION</b>VEGF overexpression is correlated to FDG uptake in patients with early-stage NPC. The SUV value reflects the glucose metabolism of NPC, and also shows the degree of oxygen insufficiency in the tumor tissue.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Fluorodeoxyglucose F18 , Pharmacokinetics , Nasopharyngeal Neoplasms , Diagnostic Imaging , Metabolism , Neoplasm Staging , Positron-Emission Tomography , Methods , Radiopharmaceuticals , Pharmacokinetics , Vascular Endothelial Growth Factor A , Genetics , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To study the mechanism of cardiotoxicity associated with Herceptin.</p><p><b>METHODS</b>Herceptin was labeled with iodine-131 using the Iodogen method. Radioimmunoimaging was performed in 5 rabbits at 3 h to 5 days following (131)I-Herceptin injection to investigate the biodistribution of Herceptin. (131)I-Herceptin uptake in each organ or tissue relative to that in the muscular tissue (O/M ratio) was calculated and compared. On the fifth day following the injection, the organs including the heart, lung, liver and muscles were taken for measurement of the weight and radiocounts. HER2 expression was measured by immunohistochemistry in these organs and tissues.</p><p><b>RESULTS</b>The O/M ratio of the heart was significantly higher than that of the lung (P=0.032) and liver (P=0.019) at 3 h after Herceptin injection, but reduced significantly at 24 h (P=0.001). The uptake of (131)I-Herceptin in the myocardium was slightly higher that that in the muscle and intestine, but lower than that in the lung and spleen. HER2 expression showed no significant difference between the myocardium and the other tissues such as the liver, lung, and kidney (H=3.236, P=0.172).</p><p><b>CONCLUSION</b>Myocardium expresses low levels of HER2 and accumulates Herceptin no more than the other tissues.</p>