1.A Fluorimetric Method for Determination of Chromium (Ⅵ)
Suling FENG ; Anna TANG ; Jing FAN
Chinese Journal of Analytical Chemistry 2001;29(5):558-560
A simple and sensitive fluorimetric method is proposed for the determination of Cr(Ⅵ).The method is based on the oxidation of Cr(Ⅵ) to the pyronine in the sulfuric acid medium.The detection limit for Cr(Ⅵ) is 2.2μg/L,the linear range of the determination is 8.0~88μg/L.The method has been used to determine Cr(Ⅵ) in electroplating waste,electroplating solution and alloy steel samples with satisfactory results.
2.Therapeutic effect of chemokine SLC combined with immune adjuvant CpG-ODN in treatment of implanted mouse melanoma
Xiangfan XU ; Zhenzhu XU ; Lihua TANG ; Anna LI ; Xianhui XU ; Chunbao LIU
Chinese Journal of Cancer Biotherapy 2010;17(1):25-29
Objective: To study the therapeutic effect of secondary lymphoid tissue chemokine (SLC) combined with CpG oligodeoxynucleotide (CpG-ODN) in treatment of implanted mouse melanoma and the possible mechanism. Methods: SLC-Fc fusion protein was prepared and its chemotaxis of lymphocytes was detected by chemotaxis assay. Implanted melanoma mouse models were established and randomly divided into 4 groups: control group, SLC-Fc group, CpG-ODN group, and SLC-Fc+CpG-ODN group. The growth of implanted tumors in each group was observed after treatment. Subtype and infiltration of lymphocytes in implanted tumor tissues were examined by flow cytometry. Results: SLC-Fc protein was successfully prepared, and it dose-dependently attracted lymphocytes (0.03, 0.3, and 3 μg/L). Intra-tumor injection SLC-Fc and CpG-ODN alone or in combination significantly inhibited growth of B16-implanted tumors. Tumor size in SLC-Fc+CpG-ODN group was significantly smaller than that in control group (P<0.01), and animals in SLC-Fc+CpG-ODN group survived longer. Tumor-infiltrated CD4~+ T, CD~8+ T, and dendritic cells (DCs) in SLC-Fc+CpG-ODN group were markedly increased as compared with those in control group (P<0.05), and tumor draining lymph nodes were dramatically enlarged. Conclusion: SLC combined with CpG-ODN can inhibit the growth of implanted melanoma by attracting CD4~+ T and CD8~+ T and promoting proliferation of DCs.
3.Accommodative stimulus response curve of emmetropes and myopes.
Anna C H YEO ; Kok Kai KANG ; Wilfred TANG
Annals of the Academy of Medicine, Singapore 2006;35(12):868-874
INTRODUCTIONMyopes are suspected to be poorer at responding to accommodative stimuli than emmetropes, and this may worsen the degree of their myopia. The study aims to compare the abilities of young adult emmetropes and myopes in responding to accommodative stimuli, as indicated by their Accommodation Stimulus Response Curves (ASRCs) in a predominantly Chinese population.
MATERIALS AND METHODSSeventeen emmetropes and 33 myopes aged between 16 and 23 years (mean, 18.6 +/- 1.2) were recruited, of whom 11 were progressing and 22 were non-progressing myopes. The ASRC gradients of subjects were measured using the methods of decreasing distance series (DDS), positive (PLS) and negative lens series (NLS).
RESULTSThe ASRC is method dependent. The gradients of the curves are significantly different among 3 methods of measurement using single-factor ANOVA (F3.057 = 44.815, P <0.01). The slopes of the accommodative errors of all subjects were steeper using the NLS method, and the lags of accommodation increased with elevated demands. No significant differences in ASRC gradients were found between emmetropes, non-progressing myopes and progressing myopes for the range of accommodative demands for each method. Progressing myopes showed the highest error towards the higher demand compared with the emmetropes and non-progressing myopes.
CONCLUSIONAccommodative responses of myopes were more sluggish though there were no statistical differences in ASRC gradients between emmetropes and myopes. It is not certain if the poorer accommodative responses were a cause, or a consequence, of myopia.
Accommodation, Ocular ; Adolescent ; Adult ; Disease Progression ; Female ; Humans ; Male ; Myopia ; physiopathology ; Refraction, Ocular
4. Long-term stability of periodontal root coverage procedures for gingival recession
Anna DAI ; Peihui DING ; Qi TANG ; Mengxin YANG ; Lili CHEN
Chinese Journal of Stomatology 2019;54(2):124-129
Gingival recession could result in root exposure, dental hypersensitivity and poor aesthetics. It has been demonstrated that varieties of root coverage procedures can significantly improve gingival recession in short-term (≤6 months), of which coronally advanced flap combined with connective tissue graft is the gold standard technique for treatment of gingival recession. It could obtain the optimally complete root coverage and maintain long-term stability (≥2 years). However, clinical knowledge about the long-term effectiveness of the other alternative graft materials remain very limited. Based on the existing clinical evidence, this article reviews coronally advanced flap, coronally advanced flap combined with connective tissue graft or alternative graft materials, with particular attention to the long-term stability of them, in order to provide reference for the design of further clinical trials and the plan of clinical treatments.
5.Compliance with noninvasive home ventilation in children with obstructive sleep apnoea.
Anna Maria NATHAN ; Jenny Poh Lin TANG ; Anne GOH ; Oon Hoe TEOH ; Oh Moh CHAY
Singapore medical journal 2013;54(12):678-682
INTRODUCTIONThis study aimed to determine compliance with noninvasive home ventilation in children with obstructive sleep apnoea and the factors affecting this compliance.
METHODSWe retrospectively reviewed 51 children who were prescribed noninvasive home ventilation for the management of obstructive sleep apnoea from 1 January 2000 until 31 May 2008. Noninvasive ventilation was started based on positive polysomnogram, i.e. obstructive apnoea hypopnea index ≥ 1/hr. Compliance was defined as the use of noninvasive ventilation ≥ 4 days/week.
RESULTSNoninvasive home ventilation was started at a median age of 11.5 years. In all, 21 (41.2 %) children were reported to be compliant with treatment. Univariate analysis revealed that the female gender (p = 0.017), presence of asthma (p = 0.023), presence of genetic syndromes (p = 0.023), use of bi-level ventilation versus continuous positive airway pressure (p = 0.027), and funding from the social work department (p = 0.049) were associated with compliance with noninvasive home ventilation. Logistic regression revealed the presence of asthma (p = 0.008) and female gender (p = 0.047) to be significantly associated with compliance with treatment. However, factors such as counselling prior to initiation of treatment, severity of obstructive sleep apnoea before initiation of treatment, obesity, use of humidification, and polysomnogram indices were not found to be associated with treatment compliance.
CONCLUSIONOnly 41.2% of the children in this study were reported to be compliant with noninvasive home ventilation. The female gender and the presence of asthma were associated with treatment compliance. Future research focusing on effective methods to improve compliance with noninvasive home ventilation in children should be undertaken.
Adolescent ; Asthma ; Child ; Child, Preschool ; Comorbidity ; Continuous Positive Airway Pressure ; Female ; Humans ; Infant ; Male ; Obesity ; complications ; Patient Compliance ; Polysomnography ; Regression Analysis ; Retrospective Studies ; Rhinitis, Allergic ; complications ; Sleep Apnea, Obstructive ; complications ; therapy