Sample size calculation is an important factor to evaluate the reliability of the diagnostic test. In this paper, a case study of the clinical diagnostic test of artificial intelligence for identification of liver contrast-enhanced ultrasound was performed to conduct two-category and multi-categories studies. Based on sensitivity and specificity, the sample size was then estimated in combination with the statistical characteristics of disease incidence, test level and one/two-sided test. Eventually, the sample size was corrected by integrating the factors of the proportion of training/test dataset and the dropout rate of cases in the medical image recognition system. Moreover, the application of Sample Size Calculator, MedCalc, PASS, and other software can accelerate sample size calculation and reduce the amount of labor.
A multiple-stimuli-responsive drug-conjugated cross-linked micelles was prepared by radical copolymerization. The chemical structure, morphology, and size of the cross-linked micelles were characterized, and the drug loading of the micelle was calculated. The experimental results indicated that the hydrodynamic size of the drug-loaded micelles were about 100 nm, and the as prepared micelles could be degraded and swelled in presence of reducing glutathione (GSH). The low critical solution temperature (LCST) of the micelle was around 39.4℃. According to the experimental results, the micelles will shrink at temperature above the LCST. Subsequently, the accumulative drug release rate was up to 91.78% under acidic (pH 5.0), reductive (GSH 10 mmol/L) and high temperature (42.0℃) conditions mimicking the tumor microenvironment, while a relatively low release rate of 1.12% was observed without stimulation. The drug-conjugated cross-linked micelles showed a strong cell uptake behavior. In the cytotoxicity assay, the micelles exhibited effective anti-cancer activity and excellent biocompatibility. In brief, the experimental results show that the as-prepared drug-conjugated cross-linked micelle exhibits multiple stimuli-responsiveness, which holds great promise for anti-cancer drug delivery.
Objective To evaluate the utility of collagen-gel droplet embedded-culture drug sensitivity test (CD-DST) in pancreatic carcinoma cell by compared with WST-8. Methods The chemosensitivity to 5-fluorouracil (5-FU), gemzar (GEM) and oxaliplatin (OXA) of pancreatic adenocarcinoma cells SW1990, PCT-3 and ASPC-1 were tested by WST-8 and CD-DST respectively. Results In a certain living cell number range (500-10 000), there was a linear correlation (r=0.991 1, P<0.05) between the integral optical density in CD-DST and the cell number. The inhibition ratios of three kinds of cell growth tested by CD-DST were higher than those tested by WST-8 (P<0.05). The results of drug chemosensitivity to 5-FU, GEM and OXA detected by two methods were uniform. Conclusion The CD-DST can be used to assay the drug chemosensitivity in vitro for pancreatic carcinoma.
Objective To explore the effect of hydrostatic pressure on intracellular free calcium concentration ([Ca2+]i) and the gene expression of transient receptor potential vanilloid (TRPV) in cultured human bladder smooth muscle cells (hb-SMCs), and to prel iminarily probe into the possible molecular mechanism of hb-SMCs prol iferation stimulated by hydrostatic pressure. Methods The passage 6-7 hb-SMCs were loaded with Ca2+ indicator Fluo-3/AM. When the hb-SMCs were under 0 cm H2O (1 cm H2O=0.098 kPa) (group A) or 200 cm H2O hydrostatic pressure for 30 minutes (group B) and then removing the 200 cm H2O hydrostatic pressure (group C), the [Ca2+]i was measured respectively by inverted laser anningconfocal microscope. When the hb-SMCs were given the 200 cm H2O hydrostatic pressure for 0 hour, 2 hours, 6 hours, 2 hours, and 24 hours, the mRNA expressions of TRPV1, TRPV2, and TRPV4 were detected by RT-PCR technique. Results The [Ca2+]i of group A, group B, and group C were (100.808 ± 1.724), (122.008 ± 1.575), and (99.918 ± 0.887) U, respectively; group B was significantly higher than groups A and C (P lt; 0.001). The [Ca2+]i of group C decreased to the base l ine level of group A after removing the pressure (t=0.919, P=0.394). The TRPV1, TRPV2, and TRPV4 genes expressed in hb-SMCs under 200 cm H2O hydrostatic pressure at 0 hour, 2 hours, 6 hours, 12 hours, and 24 hours, but the expressions had no obvious changes with time. There was no significant difference in the expressions of TRPV1, TRPV2, and TRPV4 among 3 groups (P gt; 0.05). Conclusion The [Ca2+]i of hb-SMCs increases significantly under high hydrostatic pressure. As possible genes in stretch-activated cation channel, the TRPV1, TRPV2, and TRPV4 express in hb-SMCs under 200 cm H2O hydrostatic pressure. It is possible that the mechanical pressure regulates the [Ca2+]i of hb-SMCs by opening the stretch-activated cation channel rather than up-regulating its expression.
Objective Chronic cough is often present as increasing cough reaction to various physical and chemical stimulating factors. This study is aimed to investigate the difference of cough sensitivity and its mechanisms which are not clear among different causes of chronic cough. Methods Patients with chronic cough were recruited from cough clinic of Guangzhou Institute of Respiratory Diseases between 2005 to 2010. Using a modified diagnostic algorithm of chronic cough, common causes were identified. Capsaicin cough provocation test was also performed in these patients to assess the cough threshold. The relations between cough reflex sensitivity and duration of cough, cough severity, pulmonary function, induced sputum cell counts were then investigated. Results Through the diagnostic algorithm of chronic cough, the current study evaluated 133 adult patients, including 24 cases with upper airway cough syndrome (UACS) , 26 patients with cough variant asthma (CVA) , 31 cases with eosinophilic bronchitis (EB) , 30 patients with atopic cough (AC) , 22 cases with gastroesophageal reflux induced cough (GERC) . There were 30 healthy volunteers recruited as normal control. The cough threshold of LgC5 in AC, CVA, EB, GERC and UACS was 1.70 ±0.70, 2.12 ±0.67, 2.13 ±0.69, 1.69 ±0.73, 2.16 ±0.66, respectively. The LgC5 of the normal group ( 2.63 ±0.39) was higher than those in chronic cough groups( All P lt; 0.05) . The LgC5 of AC and GERC were lower than CVA, EB and UACS ( all Plt;0.05) . Duration and daytime score of cough showed positive correlations with LgC5( r =-0. 280, -0. 168, all P lt;0.05) . Pulmonary function and differential cell count of induced sputumwere not associated with LgC5 ( all Pgt;0.05) . Conclusions Different cause of chronic cough exhbit high cough reflex sensitivity to different extent. The difference of cough sensitivity may reflect the different pathogenesis among different causes, and may be related to the type of nerve fiber dominating the cough reflex.
Inappropriate and irrational prescription of antimicrobial agents has led to increasing bacterial resistance, which has become a major concern around the world. Clinical microbiology service provides a basis and guarantee for the rational application of antimicrobial agents and an important technical support for antimicrobial stewardship, and plays an important role in promoting the rational use of antimicrobial agents. This paper summarizes and evaluates the specific role and technical requirements of clinical microbiology service in the diagnosis of infectious diseases, rational application of antimicrobial agents, hospital infection control and training of medical staff, so as to provide a technical guidance for clinical microbiology service in the antimicrobial stewardship.