Lateral flow assay is widely used in the point-of-care testing on-site and in-home testing with the advantage of being simple, rapid, sensitive and cost-effective. Proper labels are the key factors in lateral flow assay. Traditional labels include colloidal gold, selenium nanoparticle, and carbon nanoparticle, among which the colloidal gold is most commonly used. Lateral flow assay has been improved as a result of the discovery of new labels, such as quantum dots and nanozyme recently. Meanwhile, transformation of qualitative detection to quantitative detection is gradually realized. This article aims at introducing the most often used and the latest lateral flow assay labels, providing a basis theoretical investigation on screening proper labels for lateral flow assay researchers.
Objective lt;brgt;To investigate the feasibility of labeling iris pigment epithelial(IPE)cells of rabbits with 5(and 6)carboxyfluorescein diacetate succinimidyl ester(CFSE). lt;brgt; lt;brgt;Methods lt;brgt;Enzyme-assisted microdissection was used to isolate the cultured rabbitprime;s IPE cells.The third or forth subcultured IPE cells were incubated with 2.5,5,10,20,and 40 mu;mol/L of CFSE for 1,5,and10min respectively.The fluorescence intensity was detected by flow cytometry,and the leakage of CFSE and its dyeing were observed by fluorescence antibody labeling. lt;brgt;Results lt;brgt;Incubation with 20 mu;mol/L CFSE under 37℃for1minute was the most optimal condition for IPE cells labeling.The coloration of IPE cells stained by CFSE lasted 4 weeks.There was no leakage of dye from labeled rabbit IPE cells to non-labeled human IPE cells in mixed culture process. lt;brgt; lt;brgt;Conclusion lt;brgt;With the advantages of high rate of dyeing,long time of tracing,safety and convenience,CFSE can be used as a new method to label the rabbitprime;s IPE cells. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis, 2006, 22: 261-264)
Objective The combined appl ication of green fluorescent protein (GFP) and confocal laser scanning microscope three-dimensional reconstruction (CLSM-3DR) were used to monitor the construction and in vivo transplantation of tissue engineered bone (TEB), to provide for technology in selection of scaffolds and three-dimensional constructional methods. Methods After bone marrow mesenchymal stem cells (BMSCs) were isolated from a 2-year-old green goat by a combination method of density gradient centrifugation and adherent culture, and the expressions of CD29, CD60L, CD45, and CD44 in BMSCs were detected by flow cytometry. Plasmid of pLEGFP-N1 was ampl ified, digested by enzymes (Hind III, BamH I, Sal I, and Bgl II), and identified. Transfection of pLEGFP-N1 into PT67 cells was performed under the help of l iposome. Positive PT67 cells were picked out with G418, and prol iferated for harvesting virus. Based on the titre of virus, after BMSCs were infected by virus containing pLEGFP-N1, GFP positive BMSCs were collected and prol iferated for seeding cells. TEB was fabricated by GFP positive BMSCs and decalcified bone matrix (DBM) and observed by CLSM-3DR for the evaluation of the distribution and prol iferation of seeding cells. After TEB was transplanted in the defect of goat femur, CLSM was used for observing the survival and distribution of GFP positive cells in the grafts. Results The isolated cells were fibroblast-l ike morphous, with the positive expression of CD29 and CD44, and negative expression of CD60L and CD45. The digested production of pLEGFP-N1 was collected for ionophoresis, whose results showed the correct fragment length (6 900 bp). The virus of pLEGFP-N1 was harvested by transfection of pLEGFP-N1 into PT67 cells and used for further infection to obtain GFP positive BMSCs. The prol iferated GFP positive BMSCs and DBM were used for fabrication of TEB. The distribution, prol iferation, and migration of BMSCs in TEB were observed by CLSM-3DR. GFP positive cells also were observed in images of TEB graft in goat femur 28 days after transplantation. Conclusion The BMSCs labeled by GFP in three-dimensional scaffold in vivo were monitored well by CLSM-3DR. It suggests a wide use potency in monitoring of three-dimensional cultured TEB.
Objective To explore the clinical application of combination of radiolabeled colloid (99Tcm-sulphur colloid) and blue dye in sentinel lymph node biopsy (SLNB) for early-stage breast cancer. Methods SLNB was performed with the guidance of blue dye, radiolabeled colloid, and the combination method in all patients enrolled, and clinical and pathological data were recorded respectively for analysis. Results Two hundred and one patients were enrolled in this study and the SLN were successfully detected in 200 cases. The identification rate of radiolabeled colloid method and combination method was 99.5% (200/201) and 99.5% (198/199) respectively, which significantly higher than blue dye method (85.4%, P<0.001). There were no differences of accuracy rate 〔95.3% (162/170) vs. 94.5% (189/200) vs. 98.0% (194/198), P=0.185〕 and false negative rate 〔11.3% (8/71) vs. 13.9% (11/79) vs. 5.1% (4/79), P=0.165) between blue dye method, radiolabeled colloid method, and combination method. The combination method could detect more SLN than radiolabeled colloid method or blue dye method only (P<0.001). Compared to combination method, there were 12 and 7 patients miss diagnosed in blue dye method and radiolabeled colloid method, and the miss diagnosed rate was 16.0% (12/75) and 9.3% (7/75), respectively. Conclusions Compared to radiolabeled colloid and blue dye method, combination method has higher identification rate, and could identify more SLNs. It is recommended that the combination of radiolabeled colloid and blue dye should be adapted for procedure of SLNB in clinical practice.
Objective To observe whether theograde axial flow of retinal ganglion cells (RGC) in diabetic rats at the early stage was damaged. Methods Diabetic model was induced by streptozotocin in 6 adult male Sprague-Dawley (SD)rats. Fluorogold (FG) was injected to the superior colliculi 4 weeks later.Streched preparation of retina was made 12 and 72 hours after the injection, and was stained after photographed by fluorescent microscope. The proportion of RGC with different sizes labeled by FG was calculated. Other 6 normal adult male SD rats were in the control group. Results Twelve hours after injection with FG, there was no difference of the total number of RGC in experimental and control group, but the ratio of small RGC was lower in experimental group than that in the control group; 72 hours after injection with FG, The number of RGC, especially the small RGC, decreased obviously in experimental group compared with the control group. Conclusion The speed of the retrograde axial flow of RGC in diabetic rats at the early stage is affected, and the small RGC are damageable. (Chin J Ocul Fundus Dis, 2006, 22: 4-6)
Objective To introduce the evidence-based evaluation on off-label uses at home and abroad, so as to investigate a systematic method of evidence-based evaluation on off-label uses. Methods In combination with the domestic and international research literature, a systematic method of evidence-based evaluation on off-label uses was discussed from the following three aspects: sources of evidence, levels of evidence, and recommendation strength. Results Sources of evidence included Clinical Pharmacology, DRUGDEX? System, NCCN Drugs amp; Biologics Compendium and handsearched literature. Levels of evidence and recommendation strength could refer to the 2009 grade system of Oxford Centre for Evidence-Based Medicine, and the strength of recommendations and scientific support of DRUGDEX? System. Conclusion A systematic method of evidence-based evaluation on off-label uses is initially established.
Objective To find a kind of simple and effective method for purifying and label ing stromal vascular fraction cells (SVFs) so as to provide a theoretical basis for cl inical application of SVFs. Methods The subcutaneous adi pose tissue were harvested form volunteers. The adi pose tissue was digested with 0.065%, 0.125%, and 0.185% type I collagenase,respectively. SVFs were harvested after digestion and counted. After trypan blue staining, the rate of viable cells was observed. SVFs was labeled by 1, 1’-dioctadecyl-3, 3, 3’, 3’-2-tetramethy-lindocyanine perchlorate (DiI). The fluorescent label ing and growth was observed under an inverted fluorescence microscope. MTT assay was used to detect cell proliferation. Results The number of SVFs was (138.68 ± 11.64) × 104, (183.80 ± 10.16) × 104, and (293.07 ± 8.31) × 104 in 0.065% group, 0.125% group, and 0.185% group, respectively, showing significant differences among 3 groups (P lt; 0.01). The rates of viable cells were 91% ± 2%, 90% ± 2%, and 81% ± 2% in 0.065% group, 0.125% group, and 0.185% group, respectively, and it was significantly higher in 0.065% group and 0.125% group than in 0.185% group (P lt; 0.01), but no significant difference was found between 0.065% group and 0.125% group (P=0.881). Inverted fluorescence microscope showed that the cell membranes could be labeled by DiI with intact cell membrane, abundant cytoplasm, and good shape, but nucleus could not labeled. SVFs labeled by DiI could be cultured successfully and maintained a normal form. MTT assay showed that similar curves of the cell growth were observed before and after DiI labeled to SVFs. Conclusion The optimal collagenase concentration for purifying SVFs is 0.125%. DiI is a kind of ideal fluorescent dye for SVFs.
With the real-world study (RWS) becoming a hotspot for clinical research, health data collected from routine clinical practice have gained increasing attention worldwide, particularly the data related to the off-label use of drugs, which have been at the forefront of clinical research in recent years. The guidance from the National Medical Products Administration has proposed that real-world evidence (RWE) can be an important consideration in supporting label expansions where randomized controlled trials are unfeasible. Nevertheless, how to use the RWE to support the approval of new or expanded indications remains unclear. This study aims to explore the structured process for the use of RWE in supporting label expansions of approved drugs, and to discuss the key considerations in such process by reviewing the documents from relevant regulatory agencies and publications from public databases, which can inform future directions for studies in this area.
ObjectiveTo investigate the situation of off-label drug use in dose (OLDUD) of ambroxol hydrochloride injection (AHI) in perioperative period among patients for stanford type A aortic dissection in Guangdong General Hospital, so as to provide references for the rational application of AHI in clinical practice. MethodsAll medical orders of AHI for patients had aortic arch replacement for Stanford type A aortic dissection in Guangdong General Hospital between January 2005 and December 2014 were included. The patients were divided into a mild OLDUD ( < 450 mg) group, a moderate OLDUD (450 mg≤OLDUD < 900 mg) group, and a high OLDUD (≥900 mg)group. The preoperative and postoperative features, incidence of PPCs, mortality, incidence of reintubation, time of mechanical ventilation, time stay in ICU, time stay in hospital and the overall costs among three groups were compared by SPSS 22.0 software. Resultsa) A total of 549 patients were included. The incidence of OLDUD was 99.82%. The most common PMDDs were 450 mg (n=358) and 900 mg (n=88). b) The three groups were well matched for perioperative and operative variables. c) The incidence of preoperative drug use was 8.6%. The incidences (5.5% vs. 7.7% vs. 15.7%, P=0.022) and maximum doses (180 mg vs. 300 mg vs. 450 mg, P=0.014) of preoperative drug use were statistically different in mild OLDUD, moderate OLDUD and high OLDUD groups. The days of preoperative drug use were not different (3 d vs. 2.5 d vs. 2 d, P=0.307). The days of postoperative drug use (9.5 d vs. 13 d vs. 19 d, P < 0.001) and postoperative drug use in maximum doses (7 d vs. 8 d vs. 7 d, P=0.005) were different. d) The incidence of PPCs was 100%, and the mortality (8.2% vs. 6.6% vs. 9.0%, P=0.696) was not statistically different among mild OLDUD, moderate OLDUD and high OLDUD groups. However the incidence of reintubation (14.3% vs. 13.8% vs. 27%, P=0.009), time of mechanical ventilation (37 h vs. 50 h vs. 114 h, P < 0.001), time stay in ICU (138 h vs. 178.5 h vs. 316 h, P < 0.001), time stay in hospital (25 d vs. 27 d vs. 34 d, P=0.001) and the overall costs (¥ 0.17 million vs. ¥ 0.19 million vs. ¥ 0.25 million, P < 0.001) were different among three groups. Moreover, they were all increasing along with the dose of AHI. ConclusionAHI cannot improve the prognosis of patients having aortic arch replacement for Stanford Type A Aortic Dissection in a dose-dependent manner. Further well-designed prospective studies should be conducted to verification or falsification.
Objective To assess the global situation of off-label drug use in outpatient children.Methods A search was conducted in PubMed, EMbase, CBM, CNKI and VIP for collecting studies on off-label drug use in outpatient children aged 0 to 18 years, and the publication language was limited to English and Chinese. The quality assessment was based on Crombie Criteria for cross-sectional studies, and the descriptive analysis was performed to analyze the incidence of off-label drug use at all levels of medical institutes and different age groups, the common types of off-label used drugs, and the constitution ratio of off-label use drugs. Results A total of 20 cross-sectional studies were included, involving 1 933 760 children and 5 262 573 prescriptions. The results of descriptive analysis showed: a) The incidence of off-label drug use in outpatient children in primary care and tertiary care institutes were 19.5% (IQR 13.5%, 24.5%) and 26.0% (IQR 24.0%, 35.0%), respectively; b) The primary studies reported that neonate, infant and adolescent had the highest incidence of off-label drug use, while the other children had the lowest incidence; c) Drugs for respiratory system, anti-infection, sensory organs, and dermatosis were listed as the top 5 frequently used off-label drugs by more than half of the studies; d) The studies with issue of “lack of instruction for children” showed it was exactly the type with highest incidence of off-label use, while other studies without that issue showed the highest incidence was over aged off-label use. Conclusion a) Off-label drug use is common in outpatient children. The incidence of off-label drug use may be higher in tertiary care institutes than primary care institutes, and it is higher in neonate, infant and adolescent rather than other age groups of children; b) Incidence of off-label use may be higher in inpatient children than outpatient ones; c) Drugs for respiratory system, anti-infection, sensory organs, and dermatosis were most common types of off-label use; and d) Off-label use due to both “lack of instruction for children” and “over aged use” is more common. So it suggests that further studies trials should focus on fields in which clinical trials of drugs are totally absent.