Exploring the oral bacterial flora: current status and future directions

Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.     

A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa

Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies.     

抗病毒药物2,5,6-三取代-4(3H)嘧啶酮衍生物的合成及诱导干扰素活性

In order to search for more ideal antiviral drugs,21 substituted pyriiT1idinone derivatives were designed and synthesized,among which 11 were not reported before. The cheinicalstructures were characterized by elemen tal and spectral analysis. The serum interferon - inducing activity was tested in mice. All 2-amino-5-bromo-6-substituted-4-(3H)pyrimidinone compounds were shown to have interferon inducing activity.The corresponding substituted pyrimidine thiones were less active.The new compounds of 6-sulfophenyl derivatives are soluble in、water, but the interferon-inducing activity are not higher than the original compound of ABPP.     

抗病毒药物2，5，6-三取代－4（3H）嘧啶酮衍生物的合成及诱导干扰素活性

抗病毒药物２，５，６-三取代－４（３Ｈ）嘧啶酮衍生物的合成及诱导干扰素活性刘新泳，徐丽君（山东医科大学药学系济南２５００１２）取代嘧啶酮类化合物是一类小分干扰素诱导剂，有抗病毒、抗肿瘤、杀菌抑霉、诱导干扰素和白介素、免疫调节等多种生物活性（１）。目前?..     

新型缩氨基硫脲衍生物——氨基巯三唑Schiff碱的合成与抗菌活性

设计合成了新型缩氨基硫脲衍生物4-氨基-3-(呋喃-2)-5-巯基-1,2,4-三唑及其十种不同醛的Schiff碱衍生物,并进行了抑菌实验。结果表明:Schiff碱化合物结构中的甲亚胺基是该类化合物的活性功能基。苯环上更换不同的取代基对其活性有一定的影响,其中化合物4-(5-硝基亚糠基氨基)-3-(呋喃-2)-5-巯基-1,2,4-三唑(Ik)抗菌活性最高且抗菌谱最广;化合物4-亚水杨基氨基-3-(呋喃-2)-5-巯基-1,2,4-三唑(Ib)具有较强的抑霉活性。     

Effects of radiopaque contrast media on calcium uptake and phosphatidylinositol metabolism in rat brain synaptosomes.

Radiographic contrast media (RCM) used in the subarachnoid space are associated with occasional adverse reactions. This study examines the possibility that RCM reactions are caused by interactions with the plasma membrane phosphatidylinositol (PI) second messenger system. Isolated nerve endings, known as synaptosomes, were produced from rat brain homogenates. The synaptosomes were then incubated with RCM to determine if 32Pi labeling of the PIs or the uptake of 45Ca were influenced in a manner consistent with known mechanisms. The RCM metrizamide, iopamidol, iodixanol, and iotrol (but not iohexol) increased the 32Pi labeling. Hyperosmolality produced large increases in phosphatidylinositol-4-phosphate (PIP) and phosphatidylinositol-4, 5,-bisphosphate (PIP2) labeling. In the non-depolarized state iodixanol, but not metrizamide or iohexol, caused a time-dependent increase in 45Ca uptake. Iodixanol, iohexol, and metrizamide also augmented the veratrine-stimulated uptake of calcium, but none of the RCM affected the uptake of Ca resulting from potassium depolarization. The increased 32Pi labeling of the PIs caused by RCM is not directly related to Ca uptake, because the direction of change is wrong. RCM perturbations of the plasma membrane may cause an inhibition of other membrane components and systems. Hyperosmolality also may cause inhibition of membrane components. It is not known if these effects are important in clinically observed RCM toxicity.     

The influence of beta-cyclodextrin on the solubility and dissolution rate of paracetamol solid dispersions.

The effect of cyclodextrin (beta-CD) on the solubility and dissolution rate of various paracetamol dispersion powders (1:1 w/w), and tablets was studied. Lower solubility was exhibited by a spray dried solid dispersion made from paracetamol-Ethocel-Macrogol 6000 (95:2:3). The improvement in solubility was influenced by complexation with beta-CD and the crystalline nature of the powder products made by different procedures. The difference in crystallinity was confirmed by X-ray powder diffraction patterns. The dissolution rate of paracetamol from tablets made from the solid dispersions was satisfactory compared with paracetamol alone. The differences between the dissolution rate from the examined paracetamol tablets resulted from the different solubility of each powder and from the structural changes of particles which influenced the consolidation of the tablet mass.     

Defective T suppressor-inducer cell function in human immune deficiency virus-seropositive hemophilia patients

In human immune deficiency virus (HIV)-seropositive hemophilia patients, a low number of CD4 + lymphocytes is found, as well as a low CD4+/CD8+ ratio. In previous studies, it has been shown that antigen- specific T-helper cell (CD4+) function was present and no excessive antigen-specific T-suppressor cell (CD8+) function could be demonstrated. In this report, we studied another activity of CD4+ cells, namely the capacity to induce T-suppressor cell activity. The results clearly show a selective dysfunction of CD4+ suppressor-inducer (Tsi) cell function. Since these HIV-seropositive hemophilia patients showed the presence of activated B cells in the peripheral circulation refractory to antigen-specific T-helper cell signals and secreting specific antibodies spontaneously, we raised the hypothesis that the activated B cells in the patients activate the Tsi cells in vivo. This constant activation leads to a functional exhaustion of the Tsi cell pool.