Research progress on dental materials for preventing root caries / 口腔疾病防治

@#The high incidence and untreated rate of root caries, a common and frequently occurring oral disease with challenging treatment in elderly individuals, is the main cause of tooth loss among elderly people, as rapid development results in pulpitis and periapical periodontitis or residual crown and root, which has been regarded as one of the common chronic oral diseases seriously affecting the quality of life of elderly people. Thus, early intervention and prevention are important. Traditional dental materials for preventing root caries have been widely used in clinical practice; however, they have the disadvantages of tooth coloring, remineralization and low sterilization efficiency. A series of new dental materials for preventing root caries have gradually become a research hotspot recently, which have the advantages of promoting the mineralization of deep dental tissue, prolonging the action time and enhancing adhesion. Future caries prevention materials should be designed according to the characteristics of root surface caries and the application population and should be developed toward simplicity, high efficiency and low toxicity. This review describes current research regarding anti-caries prevention material application, serving as a theoretical underpinning for the research of root caries prevention materials, which is important for both promotion in the effective prevention of root caries and improvement in the status of oral health and the quality of life among old people.

Study on the strategies of problem design in preclinical medicineclass for clinical medicine speciality / 中华医学教育探索杂志

Classlearning plays an important role in clinical study.The quality of problem design affects the efficiency of classroom teaching.However,there are many defectsIn teachers' problem design.According to the training objectives and the learning characteristics of clinical medicine,the article focuses on the angle of basic medical classroom.First of all,from the three aspects of knowledge,skills and comprehensive quality,this paper expounds the significance of the efficient problem design to achieve the training goal ofclinical specialty.Then,this paper studies the shortcomings in the current problem design.Finally,this paper puts forwardfeasible suggestion for improving the efficiency of problem design in clinical basic medical classroomfrom the following four aspects:the construction of reasonable knowledge structure,simulation of clinical diagnosis,critical thinking and questions from students to teachers.

Preparation and measurement of sodium tanshinone Ⅱ-A sulfonate in mice serum and effects on big conductance calcium-activated potassium channels in porcine coronary artery smooth muscle cells / 重庆医学

Objective To discuss a method combining serum‐pharmacology and electrophysiology technology ,and to research the mechanism of dilating porcine coronary artery of sodium tanshinone Ⅱ‐A sulfonate (DS‐201) .Methods To give mice intragastric administration solution and measure DS‐201 concentration in mice serum ,and apply the serum to single channel patch to research its effect on big conductance calcium‐activated potassium channels(BKca ) in porcine coronary artery smooth muscle cells (PCASMCs) . Results The linear range of concentration containing DS‐201 serum was 0 .73 to 1 .91 μg/mL (r=0 .997 7) ,the recycle rate was 99 .85% -101 .47% ,and the concentration was(7 .32 ± 4 .25)μg/mL ;the result indicates that serum containing DS‐201 has activa‐tion effects on BKCa in PCASMCs ,while there was no statistical significance (P>0 .05) .Conclusion The establishment method of the alcohol extraction of Danshen is useful and reliable .The HPLC method of measuring DS‐201 concentration is precise .Choosing higher quality drugs or raising bioavailability can improve combination of the serum pharmacology and electrophysiological tech‐nique .

Mold Occurring on the Air Cleaner High-Efficiency Particulate Air Filters Used in the Houses of Child Patients with Atopic Dermatitis

Fungi are the known sources of irritation associated with atopic diseases (e.g., asthma, allergic rhinoconjunctivitis, and atopic eczema). To quantitatively estimate their presence in the indoor environment of atopic dermatitis-inflicted child patient's houses (ADCPHs), the high-efficiency particulate air (HEPA) filters installed inside the air cleaners of three different ADCPHs were investigated for the presence of mold. The air cleaner HEPA filters obtained from the three different ADCPHs were coded as HEPA-A, -B, and -C, respectively, and tested for the presence of mold. The colony forming units (CFUs) corresponding to the HEPA-A, -B, and -C filters were estimated to be 6.51 x 10(2) +/- 1.50 x 10(2) CFU/cm2, 8.72 x 10(2) +/- 1.69 x 10(2) CFU/cm2, and 9.71 x 10(2) +/- 1.35 x 10(2) CFU/cm2, respectively. Aspergillus, Penicillium, Alternaria, Cladosporium, Trichoderma, and other fungal groups were detected in the 2,494 isolates. The distribution of these fungal groups differed among the three filters. Cladosporium was the major fungal group in filters HEPA-A and -C, whereas Penicillium was the major fungal group in the filter HEPA-B. Nine fungal species, including some of the known allergenic species, were identified in these isolates. Cladosporium cladosporioides was the most common mold among all the three filters. This is the first report on the presence of fungi in the air cleaner HEPA filters from ADCPHs in Korea.

Standardization method for measurement of hydroxyurea by Ultra High Efficiency Liquid Chromatography in plasma of patients with sickle cell disease

Sickle cell anemia (SCA) is a recessively inherited disease characterized by chronic hemolytic anemia, chronic inflammation, and acute episodes of hemolysis. Hydroxyurea (HU) is widely used to increase the levels of fetal hemoglobin (HbF). The objective of this study was to standardize and validate a method for the quantification of HU in human plasma by using ultra high performance liquid chromatography (UPLC) in order to determine the plasma HU levels in adult patients with SCA who had been treated with HU. We used an analytical reverse phase column (Nucleosil C18) with a mobile phase consisting of acetonitrile/water (16.7/83.3). The retention times of HU, urea, and methylurea were 6.7, 7.7, and 11.4 min, respectively. All parameters of the validation process were defined. To determine the precision and accuracy of quality controls, HU in plasma was used at concentrations of 100, 740, and 1600 µM, with methylurea as the internal standard. Linearity was assessed in the range of 50-1600 µM HU in plasma, obtaining a correlation coefficient of 0.99. The method was accurate and precise and can be used for the quantitative determination of HU for therapeutic monitoring of patients with SCA treated with HU.

A anemia falciforme (AF) é uma doença hereditária recessiva caracterizada por anemia hemolítica crônica, inflamação crônica e episódios agudos de hemólise. Hidroxiureia (HU) é amplamente utilizada para aumentar os níveis de hemoglobina fetal (Hb F). O objetivo consiste em padronizar e validar um método para a quantificação de HU no plasma humano utilizando Cromatografia Líquida de Ultra Alta Eficiência (UPLC), a fim de determinar os níveis de HU em pacientes adultos com AF, tratados com HU. Utilizou-se coluna analítica de fase inversa (Nucleosil C18), fase móvel constituída por acetonitrila/água (16,7/83,3). Os tempos de retenção da HU, uréia e metiluréia foram respectivamente de 6,7, 7,7 e 11,4 minutos. Definiram-se todos os parâmetros do processo de validação. Para determinar a precisão e exatidão dos controles de qualidade utilizaram-se concentrações de 100, 740 e 1600 mM de HU no plasma, empregando como padrão interno a metiluréia. A linearidade foi avaliada no intervalo de 50 1600 mM de HU no plasma, obtendo-se coeficiente de correlação de 0,99. O método foi considerado exato e preciso e pode ser realizado com o propósito de determinação quantitativa de HU para monitorização terapêutica de pacientes com AF tratados com esse fármaco.

Assessment of microbiological air quality in hemato-oncology units and its relationship with the occurrence of invasive fungal infections: an integrative review

Worldwide aging of the human population has promoted an increase in the incidence of neoplasia, including hematological cancers, which render patients particularly vulnerable to invasive fungal infections. For this reason, air filtration in hemato-oncology units has been recommended. However, scarce literature has assessed the impact of microbiological air quality on the occurrence of fungal infections in this population. We performed an integrative review of studies in the MEDLINE database that were published between January 1980 and October 2012, using the following combinations of keywords: air × quality × HEPA, air × quality × hematology, and airborne fungal infections. The search yielded only 13 articles, suggesting that high-efficiency filtering of the ambient air in hemato-oncology units can prevent the incidence of invasive fungal infections. However, no randomized clinical trial was found to confirm this suggestion. Currently, there is no consensus about the maximum allowable count of fungi in the air, which complicates filtration monitoring, including filter maintenance and replacement, and needs to be addressed in future studies.

Guiding medical equipment procurement by human factors engineering / 中华医院管理杂志

Human factors engineering is a promising interdisciplinary subject in applied sciences.This study presented the development and research purposes of human factors engineering.Based on case studies,the authors probed into the importance of the engineering in the design,management and procurement of medical equipments,for the purpose of optimizing medical equipment design,manufacturing and procurement.

Evaluation of vaporized hydrogen peroxide fumigation as a method for the bio-decontamination of the high efficiency particulate air filter unit / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate the performance of vaporized hydrogen peroxide (VHP) for the bio-decontamination of the high efficiency particulate air (HEPA) filter unit.</p><p><b>METHODS</b>Self-made or commercially available bioindicators were placed at designated locations in the HEPA filter unit under VHP fumigation. The spores on coupons were then extracted by 0.5 h submergence in eluent followed by 200- time violent knocks.</p><p><b>RESULTS</b>Due to the presence of HEPA filter in the box, spore recovery from coupons placed at the bottom of the filter downstream was significantly higher than that from coupons placed at the other locations. The gap of decontamination efficiency between the top and the bottom of the filter downstream became narrower with the exposure time extended. The decontamination efficiency of the bottom of the filter downstream only improved gently with the injection rate of H2O2 increased and the decontamination efficiency decreased instead when the injection rate exceeded 2.5 g/min. The commercially available bioindicators were competent to indicate the disinfection efficiency of VHP for the HEPA filter unit.</p><p><b>CONCLUSION</b>This assay developed can detect all 16 β-lactams demanded by the European Union (EU). The whole procedure takes only 45 min and can detect 42 samples and the standards with duplicate analysis.</p>

Estudo comparativo da veiculação do diclofenaco sódico pela fonoforese de alta e baixa frequência em ratos / Comparative study of sodic diclofenaco veiculation by fonoforesis using high and low frequency in rats

Objetivo: estudar a aplicação do ultrassom terapêutico com alta frequência-3MH em estudo comparativo com aplicação do ultrassom terapêutico de baixa frequência-1MHz, na indução do aumento na absorção transcutânea do diclofenaco de sódio pela pele de ratos. Método: estudo experimental utilizando 15 ratos machos, adultos, da linhagem Wistar, com peso entre 250 a 350 gramas, distribuídos em três grupos: Alta, Baixa Frequência e Controle de 5 ratos cada. Foram coletadas 4 amostras de sangue de cada animal, nos tempos de 0? antes da aplicação do ultrassom, 30?, 60? e 90? minutos após a realização da técnica específica para cada grupo. Na leitura das amostras, foi utilizado o equipamento de Cromatografia Líquida de Alta Eficiência-CLAE. Resultado: a análise foi obtida através do método não paramétrico, ANOVA de Kruskal-Wallis, não comprovando diferença estatisticamente significante entre os grupos analisados no que diz respeito a maior absorção do fármaco. Conclusão: os resultados obtidos sugerem novos estudos, que busquem aperfeiçoar o método aplicado e possa agregar maiores conhecimentos ao assunto pesquisado o que possibilitará resultados cada vez mais precisos.

Objective: to study the application of therapeutic ultrasound with high frequency-3MH in a comparative study with application of therapeutic ultrasound, low-frequency 1MHz-induced increase in transcutaneous absorption of diclofenac sodium by the skin of mice. Method: an experimental study using 15 male rats, adult male rats, weighing 250 to 350 grams were divided into three groups: High, Low Frequency Control and 5 mice each. We collected 4 blood samples from each animal at 0 'prior to the application of ultrasound, 30', 60 'and 90' minutes after the completion of specific techniques for each group. In reading the samples, we used the equipment Chromatography High Performance Liquid-HPLC. Result: the analysis was performed using the method nonparametricANOVA Kruskal-Wallis test does not confirm a statistically significant difference between the groups with regard to the greater absorption of the drug. Conclusion: the results suggest further studies that seek to improve the methodology used, and may add more knowledge to the subject researched the results will enable more precise.

Study on HPLC Fingerprint of Smilacis Rhizoma / 中华中医药杂志

Objective:Adopting RP-HPLC method,to study and establish the fingerprint of smilacis rhizome.Methods: YMC-Pack ODS-A(5 ?m,4.6 mm?250 mm) chromatographic column,acetonitrile-0.05% phosphoric acid solution gradient elution were applied;with flow rate of 0.8 ml/min and UV detector at 290 nm.Results: Technology investigation indicated that the analytical method this study established has a better reproducibility.The similarity of smilacis rhizoma fingerprints from different sources is better;smilacis rhizome and its three confusions fingerprints are apparently different.Conclusion: HPLC fingerprint analysis can be a method for quality control of medical material of smilacis rhizoma.

Discussion on Compulsory Matching Security Equipment of Biosafety Laboratory / 医疗卫生装备

The construction of biosafety laboratory was highly concerned these years because of the spread of high pathogenic diseases including SARS and avian influenza. In the past several years, the construction of many BSL-2/3 laboratories played an important role in preventing the dissemination of pathogens involved in the research. Meanwhile, serious problems were also raised because some project designers or constructors were not clear with the compulsory safety equipments in these laboratories so that the requirement of zero-leakage could not be achieved. The compulsory safety equipments emerging and disposing solid, liquid and gas offal in the biosafety laboratory were reviewed. The R&D of special equipments in biosafety laboratory in China was also introduced.

Content Determination of Paeoniflorin in Blood Plasma with Reversed-phase High-efficiency Liquid Chromatography / 中成药

The method, established for analysis of paeoniflorin in blood plasma, appeared a good linear relationship(r=0.9998). Using meta-hydroxybenzoic acid as internal standard and calibration factor combined, the quantitation precision of method could be raised. The result of determination of calibration factor conformed with the chromatography prescriptions in "Pharmacopoeia of China" (edited in 1990). The average recovery reached up 97.13％. The minimum detection amount was 5.6ng. The coefficients of within-day and between-day variation were 0.39％ and 1.17％, respectively. This method is suitable for paeoniflorin analysis of in vivo sample . At present,the in vivo absorption of Baihegujintang Granules (containing Radix Paeoniae alba or Radix Paeoniae rubra) by rabbit is preliminarily investigated utilizing this method.

Content Determination of Icariin in Fuchun Tablets with Reversed-phase High-efficiency Liquid Chromatography / 中成药

A simple, rapid and accurate method is described for the determination of icariin in Fuchun Tablets by reversed-phase high-efficiency liquid chromatography. The samples were first extracted with 70% alcohol for 50 minutes The resulting solutions were chromatographed on aYWG-C18 column.By using a mobile phase of methanoltetrahydrofuran-water (26.5:15.9:56.7) and a detection wavelength at 274 nm, the recovery for 101.02%, CV=2.4%,are obtained.The method can be employed for the quality control of Fuchun Tablets.

Test Methods of HEPA Filter and their Application / 医疗卫生装备

Four test methods of HEPA filter such as D.O.P test, sodium flame test, oil mist test and particle counting test,are introduced briefly.Furthermore the numerical relations of the above four methods are analyzed. The differences between efficiency of test and practical efficiency and the aspects needed to be considered when testing filter for bio-protection are discussed at the end.