Prevalence and risk factors of periodontal disease among pre-conception Chinese women.

BACKGROUND: Periodontal disease is one of the most common chronic infectious diseases. It has been reported that periodontal disease is associated with various adverse pregnancy outcomes including preterm birth, low birth weight, and gestational diabetes mellitus. Given the fact that the treatment for periodontal disease during pregnancy was ineffective in improving pregnancy outcomes by most of studies, the pre-conception period has been put forward as a more optimal time. However, very few studies have reported the prevalence of periodontal disease among pre-conception women. This study aimed to examine the prevalence and risk factors of periodontal disease among Chinese pre-conception women. METHODS: A survey was conducted among pre-conception women at the Maternal and Child Health Hospital, Changzhou, China between January 2012 and December 2014. A total of 987 pre-conception women were recruited for a full-mouth dental examination after providing informed consent. A dental examination was carried out by probing six sites per tooth using a manual UNC-15 probe and a recording form. RESULTS: The overall rate of periodontal disease among participants was 73.9% (729/987) (95% confidence interval (CI): 71.0-76.6%). Among women with periodontal disease, 48.0% of cases were mild, 50.9% were moderate and 1.1% were severe. Self-reported bleeding during tooth brushing was the only significant predictive factor for overall periodontal disease (adjusted odds ratio (aOR): 3.71, 95% CI: 2.24, 6.15, P < 0.001) and moderate/severe periodontal disease (aOR: 5.17, 95% CI: 3.05, 8.79, P < 0.001). CONCLUSION: A high prevalence of periodontal disease was found in pre-conception Chinese women. Women who have bleeding during tooth brushing could be at increased risk of periodontal disease, and might require further oral health care.

A randomized controlled trial of pre-conception treatment for periodontal disease to improve periodontal status during pregnancy and birth outcomes.

BACKGROUND: Evidence has suggested that periodontal disease is associated with an increased risk of various adverse pregnancy and birth outcomes. However, several large clinical randomized controlled trials failed to demonstrate periodontal therapy during pregnancy reduced the incidence of adverse pregnancy and birth outcomes. It has been suggested that the pre-conception period may be an optimal period for periodontal disease treatment rather than during pregnancy. To date, no randomized controlled trial (RCT) has examined if treating periodontal disease before pregnancy reduces adverse birth outcomes. This study aims to examine if the pre-conception treatment of periodontal disease will lead to improved periodontal status during late pregnancy and subsequent birth outcomes. METHODS/DESIGN: A sample of 470 (235 in each arm of the study) pre-conception women who plan to conceive within one year and with periodontal disease will be recruited for the study. All participants will be randomly allocated to the intervention or control group. The intervention group will receive free therapy including dental scaling and root planning (the standard therapy), supragingival prophylaxis, and oral hygiene education. The control group will only receive supragingival prophylaxis and oral hygiene education. Women will be followed throughout their pregnancy and then to childbirth. The main outcomes include periodontal disease status in late pregnancy and birth outcomes measured such as mean birth weight (grams), and mean gestational age (weeks). Periodontal disease will be diagnosed through a dental examination by measuring probing depth, clinical attachment loss and percentage of bleeding on probing (BOP) between gestational age of 32 and 36 weeks. Local and systemic inflammatory mediators are also included as main outcomes. DISCUSSION: This will be the first RCT to test whether treating periodontal disease among pre-conception women reduces periodontal disease during pregnancy and prevents adverse birth outcomes. If the effect of pre-pregnancy periodontal treatment is confirmed, this intervention could be recommended for application in low- or middle-income countries to improve both oral health and maternal and child health. TRIAL REGISTRATION: This trial is registered with Chinese Clinical Trial Registry (ChiCTR): ChiCTR-TRC-12001913.

Structural factors and mechanisms underlying the improved photodynamic cell killing with silicon phthalocyanine photosensitizers directed to lysosomes versus mitochondria.

The phthalocyanine photosensitizer Pc 4 has been shown to bind preferentially to mitochondrial and endoplasmic reticulum membranes. Upon photoirradiation of Pc 4-loaded cells, membrane components, especially Bcl-2, are photodamaged and apoptosis, as indicated by activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase, is triggered. A series of analogs of Pc 4 were synthesized, and the results demonstrate that Pcs with the aminopropylsiloxy ligand of Pc 4 or a similar one on one side of the Pc ring and a second large axial ligand on the other side of the ring have unexpected properties, including enhanced cell uptake, greater monomerization resulting in greater intracellular fluorescence and three-fold higher affinity constants for liposomes. The hydroxyl-bearing axial ligands tend to reduce aggregation of the Pc and direct it to lysosomes, resulting in four to six times more killing of cells, as defined by loss of clonogenicity, than with Pc 4. Whereas Pc 4-PDT photodamages Bcl-2 and Bcl-xL, Pc 181-PDT causes much less photodamage to Bcl-2 over the same dose-response range relative to cell killing, with earlier cleavage of Bid and slower caspase-3-dependent apoptosis. Therefore, within this series of photosensitizers, these hydroxyl-bearing axial ligands are less aggregated than is Pc 4, tend to localize to lysosomes and are more effective in overall cell killing than is Pc 4, but induce apoptosis more slowly and by a modified pathway.

Effect of the functionalization of the axial phthalocyanine ligands on the energy transfer in QD-based donor-acceptor pairs.

This study examines the electronic coupling between quantum dots (QDs) and molecules on their surfaces as a function of the modality of their interaction. As a probe, the energy transfer (ET) between CdSe QDs and phthalocyanines (Pcs) was monitored and evaluated with regard to the functionalization of the axial phthalocyanine ligand, bulkiness of the functional group bridging the QD donor and Pc acceptor, and the number of the functionalized axial ligands. New silicon PCs and their conjugates with CdSe QDs were synthesized. The ET efficiency and kinetics were studied by steady state and femtosecond time-resolved absorption spectroscopy. We observed a decrease in ET efficiency with the increase in functional group bulkiness, which could be explained by increasing steric hindrance between the ET pair. In addition, a higher ET efficiency was observed for amino and thiol functionalized Pcs compared to Pcs without functional group on the axial alkyl chain.

Nicotine Inhibits Cisplatin-Induced Apoptosis via Regulating α5-nAChR/AKT Signaling in Human Gastric Cancer Cells.

Gastric cancer incidence demonstrates a strong etiologic association with smoking. Nicotine, the major component in tobacco, is a survival agonist that inhibits apoptosis induced by certain chemotherapeutic agents, but the precise mechanisms involved remain largely unknown. Recently studies have indicated that α5-nicotinic acetylcholine receptor (α5-nAChR) is highly associated with lung cancer risk and nicotine dependence. Nevertheless, no information has been available about whether nicotine also affects proliferation of human gastric cancer cells through regulation of α5-nAChR. To evaluate the hypothesis that α5-nAChR may play a role in gastric cancer, we investigated its expression in gastric cancer tissues and cell lines. The expression of α5-nAChR increased in gastric cancer tissue compared with para-carcinoma tissues. In view of the results, we proceeded to investigate whether nicotine inhibits cisplatin-induced apoptosis via regulating α5-nAChR in gastric cancer cell. The results showed that nicotine significantly promoted cell proliferation in a dose and time-dependent manner through α5-nAChR activation in human gastric cells. Furthermore, nicotine inhibited apoptosis induced by cisplatin. Silence of α5-nAChR ablated the protective effects of nicotine. However, when co-administrating LY294002, an inhibitor of PI3K/AKT pathway, an increased apoptosis was observed. This effect correlated with the induction of Bcl-2, Bax, Survivin and Caspase-3 by nicotine in gastric cell lines. These results suggest that exposure to nicotine might negatively impact the apoptotic potential of chemotherapeutic drugs and that α5-nAChR/AKT signaling plays a key role in the anti-apoptotic activity of nicotine induced by cisplatin.

Highly enantioselective deracemization of linear and vaulted biaryl ligands.

[reaction: see text] A copper-mediated deracemization of the vaulted biaryl ligands VANOL and VAPOL can be readily achieved in the presence of (-)-spartiene. The optimal procedure involves the in situ generation of copper(II) and leads to the reproducible formation of (S)-VANOL and (S)-VAPOL in greater than 99% ee from the racemates. This method is superior to existing procedures for BINOL (92% ee).

Synthesis and photophysical properties of silicon phthalocyanines with axial siloxy ligands bearing alkylamine termini.

Eleven silicon phthalocyanines which can be grouped into two homologous series [SiPc[OSi(CH3)2(CH2)(n)N(CH3)2]2, n = 1-6 (series 1), and SiPc[OSi(CH3)2(CH2)3N((CH2)(n)H)2]2, n = 1-6 (series 2)] as well as an analogous phthalocyanine, SiPc[OSi(CH3)2(CH2)3NH2]2, were synthesized. The ground state absorption spectra, the triplet state dynamics, and singlet oxygen quantum yields of 10 of these phthalocyanines were measured. All compounds displayed similar ground state absorption spectral properties in dimethylformamide solution with single Q band maxima at 668 +/- 2 nm and B band maxima at 352 +/- 1 nm. Photoexcitation of all compounds in the B bands generated the optical absorptions of the triplet states which decayed with lifetimes in the hundreds of microseconds region. Oxygen quenching bimolecular rate constants near 2 x 10(9) M(-1) s(-1) were measured, indicating that energy transfer to oxygen was exergonic. Singlet oxygen quantum yields, phi(delta), were measured, and those phthalocyanines in which the axial ligands are terminated by dimethylamine residues at the end of alkyl chains having four or more methylene links exhibited yields near > or = 0.35. Others gave singlet oxygen quantum yields near 0.2, and still others showed singlet oxygen yields of <0.1. The reduced singlet oxygen yields are probably caused by a charge transfer quenching of the 1pi,pi* state of the phthalocyanine by interaction with the lone pair electrons on the nitrogen atoms of the amine termini. In some cases, these can approach and interact with the electronically excited pi-framework, owing to diffusive motions of the flexible oligo-methylene tether.