Association analysis between the -2518MCP-1(A/G) polymorphism and generalized aggressive periodontitis in a Chinese population

BACKGROUND AND OBJECTIVE

It has been suggested that aggressive periodontitis has a genetic basis. Monocyte chemoattractant protein 1 (MCP-1) plays a critical role in the recruitment of monocytes and the development of periodontitis. The -2518MCP-1(A/G) polymorphism has been implicated as a risk or susceptibility factor for a variety of autoimmune conditions and inflammatory diseases. The intent of this investigation was to study whether the -2518MCP-1(A/G) polymorphism is associated with generalized aggressive periodontitis in the Chinese population.

MATERIAL AND METHODS

One hundred and twenty-four patients with generalized aggressive periodontitis and 94 healthy subjects were included in this case-control study. Genomic DNA was isolated from a peripheral blood sample obtained from each subject. Gene polymorphisms of -2518MCP-1(A/G) were analyzed by a standard polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. A logistic regression analysis was performed to test the association between the -2518MCP-1(A/G) genotype (alleles) and generalized aggressive periodontitis with adjustment of the major covariates (gender, age and smoking status).

RESULTS

There was no significant association of the -2518MCP-1(A/G) polymorphism with generalized aggressive periodontitis in the unstratified subjects. However, when patients were stratified by gender, the frequency of the G(+) genotype was significantly lower in female patients with generalized aggressive periodontitis compared with female controls (p = 0.036, adjusted odds ratio = 0.3, 95% CI: 0.1-0.9). In female patients with generalized aggressive periodontitis, the probing pocket depth was larger in subjects with the AA genotype than in subjects with the G(+) genotype (5.07 mm vs. 4.30 mm; Z = -2.470, p = 0.014).

CONCLUSION

The polymorphisms of -2518MCP-1 may play an important role in determining generalized aggressive periodontitis susceptibility in this cohort of Chinese women.

Variation in sequence and expression of the avian FTO, and association with glucose metabolism, body weight, fatness and body composition in chickens

OBJECTIVE

The fat mass and obesity-associated gene (FTO), a crucial gene that affects human obesity and metabolism, has been widely studied in mammals but remains poorly characterized in birds. We aimed to identify variant FTO transcripts in domestic avian species, and to characterize the expression and biological functions of FTO in chickens.

METHODS

Variant FTO transcripts and their expression in birds were investigated using RACE and real-time quantitative reverse transcriptase-PCR technology. The effects of FTO on glucose metabolism, growth and body composition were determined by fasting and various diet treatments, as well as association analysis in a F₂ resource population. The function of cFTO1 was further studied by overexpression in chick embryo fibroblast (CEF) cells.

RESULTS

Variant FTO transcripts were identified in chicken (cFTO1 to cFTO4), duck (dFTO1, dFTO2 and dFTO4) and goose (gFTO1, gFTO2 and gFTO5). In the chicken, the complete transcript (cFTO1) was predominantly expressed in the leg muscle, pituitary, hypothalamus and cerebellum. Fasting increased both cFTO1 and PGC1α gene expression in the cerebrum, liver, breast muscle and subcutaneous fat, but decreased expression in the pituitary and anterior hypothalamus. In all tested tissues in chickens, a high-glucose diet markedly increased cFTO1 and PGC1α expression. Feeding a high-fat diet increased both cFTO1 and PGC1α expression, except in the pituitary. Overexpression of cFTO1 in CEF cells significantly increased the expression of PGC1α (2.5-fold), STAT3 (2.2-fold) and HL (1.5-fold), a cluster of genes related to energy metabolism. A total of 65 single nucleotide polymorphisms (SNPs) were identified in chicken FTO, and 18 tested SNPs were significantly associated with traits of body weight, body composition and fatness.

CONCLUSIONS

These data collectively indicate that FTO is related to glucose metabolism, body weight, fatness and body composition in birds, thus expanding knowledge of FTO function to non-mammalian species.

Dosimetric variations of target volumes and organs at risk in nasopharyngeal carcinoma intensity-modulated radiotherapy

OBJECTIVE

The aim of this study was to evaluate the actual dose variability to the targets and organs at risk (OARs) during nasopharyngeal carcinoma (NPC) intensity-modulated radiotherapy (IMRT) and to investigate the significance of replanning.

METHODS

11 NPC patients were included in this study. Each patient had both a planning CT and weekly repeated CT. Simulated plans that were generated by using the same beam configurations mapped to the repeated CT represented the actual delivered doses to the target volumes and OARs. An IMRT replanning was performed with the fifth week CT scan. Doses among the initial plan, the simulated plans and replanning were compared.

RESULTS

There were no significant dosimetric differences in the gross tumour volume, clinical target volume (CTV) 1 or CTV2 for either the simulated plans or the replanning compared with the initial plan. Dosimetric variability of both parotid glands and the brain stem were unique to each individual, and doses to the spinal cord were always maintained within the limit. Replanning in the fifth week had significantly decreased the doses delivered to both parotids (p-values of the mean dose were 0.015 and 0.026 for the left and right parotid, respectively), whereas it did not reduce the doses to the brain stem and spinal cord. There was no relationship between dose variability and weight loss.

CONCLUSIONS

There are no significant dose changes for target volumes and spinal cord, and doses to the brain stem and both parotid glands changed individually during NPC IMRT. Replanning helps to spare bilateral parotids.

Change in mortality risk over time in young kidney transplant recipients

Mortality risk for kidney transplant recipients may change with increasing accumulated exposure to the "transplantation milieu." We sought to characterize changes over time in mortality rate and in age-, sex- and race-standardized mortality ratios (SMR) relative to the general population, and to estimate the association between increasing time since first transplant and mortality risk. A total of 18 911 patients who received a first transplant at <21 years old (1983-2006), and whose data were recorded in the USRDS, were studied. There were 2713 deaths over a median follow-up of 8.9 (interquartile range 4.0-14.5; maximum 23) years. Among those with graft function, mortality was highest in the first post transplant year; beyond the first year of the first transplant, age-adjusted mortality rates and SMRs decreased slightly over follow-up. Cause of death was cardiovascular for 34.6%, infection for 19.5%, malignancy for 5.8%, other for 21.4% and unknown for 18.7%. For every 1-year time increment after the end of the first post transplant year, age-adjusted all-cause and cardiovascular mortality rates fell by 1% (p = 0.06) and 16% (p = 0.007), respectively; infection-related mortality rate did not change over time (p = 0.5). These results suggest that exposure to the transplantation milieu has no cumulative negative effects on cardiovascular health over the long term.

Stability and nonlinear optical properties of ZnO nanoparticles

Photoluminescence (PL) of ZnO nanoparticles of different surface states and sizes grown by several methods has been measured. The origin of luminescence and dependence of the luminescence spectrum shape and intensity on 325 nm excitation laser power are studied. Strong ultraviolet emission at 3.26 eV, weak violet emission around 3.12 eV and weak green emission at 2.40 eV have been observed in 16 nm nanoparticles capped by octylamine grown by non-hydrolytic method. The nanoparticles are stable under high power laser radiation and their PL intensity increases nonlinearly with an increasing laser power. As the nanoparticle size decreases to 12 nm, high power laser produces nonradiative centers which may quench the luminescence in a degree. Nanoparticles of 8 nm capped by PVP and uncapped nanoparticles of 14 nm are unstable and their luminescence depends on the excitation laser power. High power laser can quench O vacancy emission and enhance ultraviolet emission in PVP capped nanoparticles while vacancy emission can not be quenched in uncapped nanoparticles.

Influence of flavonoid extracts from celery on oxidative stress induced by dichlorvos in rats

The present work was to investigate the effects of flavonoid extracts from celery on oxidative stress induced by dichlorvos (DIC) in male Wistar rats maintained on a normal diet. The rats were given DIC through intragastric administration by the dose of 7.2 mg/kg·body weight (bw)/day and additionally added 5% flavonoid extracts to the diet for 4 weeks continuously. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione-S-transferase (GST) and the content of malondialdehyde (MDA) in livers of rats were measured at the end of the experiment. Under the influence of DIC, there were significant decrease in the activities of SOD, CAT and GST and significant increase in GPx activity and MDA content. The results also showed that the activities of SOD, GST and CAT in the DIC-treated group declined significantly when compared with the flavonoid extracts group and the DIC + flavonoid extracts group, respectively. With regard to GPx activity and MDA content, significant increase were showed in the DIC-treated group in comparison to those in the flavonoid extracts group and the DIC + flavonoid extracts group, respectively. The observations presented lead us to conclude the harmful effects of DIC during the exposure and the protective role of flavonoids in minimizing these effects.

Systemic and acute administration of parathyroid hormone-related peptide(1-36) stimulates endogenous beta cell proliferation while preserving function in adult mice

AIMS/HYPOTHESIS

A major focus in the treatment of diabetes is to identify factors that stimulate endogenous beta cell growth while preserving function. The first 36 amino acids of parathyroid hormone-related protein (PTHrP) are sufficient to enhance proliferation and function in rodent and human beta cells in vitro. This study examined whether acute and systemic administration of the amino-terminal PTHrP(1-36) peptide can achieve similar effects in rodent beta cells in vivo.

METHODS

Adult male mice were injected with 40, 80 or 160 μg of PTHrP(1-36) per kg body weight or with vehicle for 25 days. Glucose and beta cell homeostasis, as well as expression of differentiation markers and cell cycle genes were analysed.

RESULTS

All three doses of PTHrP(1-36) significantly enhanced beta cell proliferation in vivo at day 25, with 160 μg/kg PTHrP(1-36) increasing proliferation as early as day 5. Importantly, the two higher doses of PTHrP(1-36) caused a significant 30% expansion of beta cell mass, with a short-term improvement in glucose tolerance. PTHrP(1-36) did not cause hypercalcaemia, or change islet number, beta cell size, beta cell death or expression of differentiation markers. Analysis of islet G1/S cell cycle proteins revealed that chronic overabundance of PTHrP(1-139) in the beta cell significantly increased the cell cycle activator cyclin D2 and decreased levels of cyclin-dependent kinase 4 inhibitor (p16( Ink4a ) [Ink4a also known as Cdkn2a]), but acute treatment with PTHrP(1-36) did not.

CONCLUSIONS/INTERPRETATION

Acute and systemic administration of PTHrP(1-36) increases rodent beta cell proliferation and mass without negatively affecting function or survival. These findings highlight the future potential therapeutic effectiveness of this peptide under diabetes-related pathophysiological conditions.

Microwave and terahertz wave sensing with metamaterials

We have designed, fabricated, and characterized metamaterial enhanced bimaterial cantilever pixels for far-infrared detection. Local heating due to absorption from split ring resonators (SRRs) incorporated directly onto the cantilever pixels leads to mechanical deflection which is readily detected with visible light. Highly responsive pixels have been fabricated for detection at 95 GHz and 693 GHz, demonstrating the frequency agility of our technique. We have obtained single pixel responsivities as high as 16,500 V/W and noise equivalent powers of 10(-8) W/Hz(1/2) with these first-generation devices.

Brain-derived neurotrophic factor-activated astrocytes produce mechanical allodynia in neuropathic pain

Neuropathic pain management is challenging for physicians and a vexing problem for basic researchers. Recent studies reveal that activated spinal astrocytes may play a vital role in nerve injury-induced neuropathic pain, although the mechanisms are not fully understood. We have found increased glial fibrillary acidic protein (GFAP) expression, a hallmark of reactive gliosis, and elevated brain-derived neurotrophic factor (BDNF) expression in the dorsal horn in a rat model of allodynia induced by spinal nerve ligation (SNL). The high GFAP expression and mechanical allodynia that SNL induces were prevented by the intrathecal injection of the BDNF-sequestering fusion protein TrkB/Fc. Additionally, mechanical allodynia and GFAP overexpression was induced by the spinal administration of exogenous BDNF to naive rats, and exogenous BDNF given together with fluorocitrate, an astrocytic metabolism inhibitor, inhibited allodynia and GFAP upregulation. Exogenous BDNF also activated the astrocytes directly when tested in vitro. Furthermore, intrathecal administration of BDNF-stimulated astrocytes also induced mechanical allodynia in naive rats. All of these results indicate that astrocytes activated by BDNF might contribute to mechanical allodynia development in neuropathic pain in rats.

An EGFR inhibitor enhances the efficacy of SN38, an active metabolite of irinotecan, in SN38-refractory gastric carcinoma cells

BACKGROUND

Acquired drug resistance to irinotecan is one of the significant obstacles in the treatment of advanced gastric cancer. This study was performed to clarify the effect of epidermal growth factor receptor (EGFR) inhibitors in combination with SN38, an active metabolite of irinotecan, on the proliferation of irinotecan-refractory gastric cancer.

METHODS

Two irinotecan-resistant gastric cancer cell lines, OCUM-2M/SN38 and OCUM-8/SN38 were, respectively, established by stepwise exposure to SN38 from the parent gastric cancer cell lines OCUM-2M and OCUM-8. The combination effects of two EGFR inhibitors, gefitinib and lapatinib, with SN38 on proliferation, apoptosis, and cell cycle on gastric cancer cells were examined.

RESULTS

Gefitinib or lapatinib showed synergistic anti-tumour effects against OCUM-2M/SN38 and OCUM-8/SN38 cells when used in combination with SN38, but not against OCUM-2M or OCUM-8 cells. SN38 increased the expression of EGFR and HER2 in OCUM-2M/SN38 and OCUM-8/SN38 cells. The combination of an EGFR inhibitor and SN38 significantly increased the levels of apoptosis-related molecules, caspase-6, p53, and DAPK-2, and resulted in the induction of apoptosis of irinotecan-resistant cells. The EGFR inhibitors increased the S-phase and decreased the UGT1A1 and ABCG expression in irinotecan-resistant cells. The SN38 plus Lapatinib group more effectively suppressed in vivo tumour growth by OCUM-2M/SN38 cells than either alone group.

CONCLUSION

The combination treatment with an EGFR inhibitor and irinotecan might produce synergistic anti-tumour effects for irinotecan-refractory gastric cancer cells. The regulation of SN38 metabolism-related genes and cell cycle by EGFR inhibitors might be responsible for the synergism.

Association analysis of BANK1 gene with psoriasis in Southern Han Chinese

Psoriasis is a chronic inflammatory skin disease with an immunogenetic background. This study aimed to determine the association between three functional SNPs of BANK1 (rs10516487, rs17266594 and rs3733197) with psoriasis in Southern Han Chinese population by determining their frequency in 242 patients with psoriasis and 317 healthy individuals. The genotype frequencies of the detected polymorphisms were analysed in relation to the susceptibility of psoriasis. Our data show that there is no significant difference in genotype distribution for the three BANK1 SNPs between patients and healthy controls. The AA frequency of rs3733197 is significantly higher in patients with psoriasis onset before the age of 23 than in those with late disease onset (P =  0.0069). In addition, analysis on BANK1 haplotype also suggests a protective role for TGC and CAT haplotype from psoriasis (OR 0.55, 95% CI: 0.34-0.89; P = 0.0144; OR 0.62, 95% CI: 0.42-0.92; P = 0.0175), whereas CGT haplotype is associated with increased risk of the disease (OR 1.38, 95% CI: 1.05-1.81, P = 0.0203). Overall, our result indicates that polymorphism in BANK1 is associated with susceptibility to psoriasis in Southern Han Chinese.

An oncogenic role of miR-142-3p in human T-cell acute lymphoblastic leukemia (T-ALL) by targeting glucocorticoid receptor-α and cAMP/PKA pathways

MicroRNAs (miRNAs) are a family of 19-24 nucleotide non-coding RNAs with posttranscriptional regulatory functions. The involvement of miRNAs in normal hematopoiesis implies that deregulated miRNAs might contribute to leukemogenesis. To date, although certain miRNAs have been established a clear oncogenic role in hematological malignancies, other individual miRNAs potentially involved in human leukemogenesis still remain elusive. In this report, we showed that miR-142-3p was upregulated in human T-leukemic cell lines and primary T-leukemic cells isolated from T-cell acute lymphoblastic leukemia (T-ALL) patients and its expressive levels were correlated with patients' prognosis. Such an oncogenic role of miR-142-3p could be explained by its targeting cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) and glucocorticoid receptor alpha (GRα). High levels of miR-142-3p resulted in low levels of cAMP and weak activity of PKA, thus relieving the inhibitory effect of PKA on T-leukemic cell proliferation. Meanwhile, miR-142-3p decreased GRα protein expression by directly targeting the 3'-untranslational region of GRα mRNA, leading to glucocorticoid resistance. Transfection of the miR-142-3p inhibitor effectively converted glucocorticoid resistance, because of the resultant increase of GRα expression and PKA activity. These findings suggest that miR-142-3p is critical in T-cell leukemogenesis and may serve as a potential therapeutic target in T-ALL patients.

Current Insights into the role of HIF-1 in cutaneous wound healing

Hypoxia Inducible Factor-1 (HIF-1) is considered the major coordinator of the cellular adaptive response to hypoxia. Over recent years, its activity in the context of wound healing has been the object of increasing investigation. On the molecular level, HIF-1 transcriptional target products have been shown to regulate the process of endothelial cell survival, migration and proliferation (VEGF, ANGPT-1, ANGPT-2, ANGPT-4, FGF-2, PlGF, PDGF-B, RGC-32), vascular smooth muscle cell migration and proliferation (FGF-2, EGF, PDGF, thrombospondin) and mobilization of Circulating Angiogenic Cells to the periphery (SFD-1/CXCR4). Studies on the effect of HIF-1 on the expression and activity of extracellular cell matrix modifying enzymes, such as MMPs and prolidase, have been conducted in the context of tumor angiogenesis and metastasis, and have resulted in controversial findings. A growing body of evidence suggests that HIF-1 also affects reepithelialization of the wound bed, through increasing keratinocyte migration, but decreasing their proliferation. Diminished HIF-1 levels and activity have been documented in conditions of impaired wound healing, such as wound healing in aged and in diabetic mice. The increasing number of studies on the role of HIF-1 in wound healing, apart from answering certain questions, has also raised an equal number, if not more. Clarifying the topics that still remain unclear could introduce a new era of HIF-1 targeted management of a wide range of problematic wounds.

Differential effects of down-regulated steroidogenic factor-1 on basal and angiotensin II-induced aldosterone secretion

Aldosterone synthase (CYP11B2) is responsible for the final step in aldosterone synthesis and is importantly regulated by angiotensin-II (Ang II) through diverse pathways. However, under pathological conditions, such as in hyperaldosteronism, the regulation becomes disordered. The transcription factor steroidogenic factor-1 (SF-1) is important in regulating the endocrine system and is overexpressed in aldosterone-producing adenoma (APA), a common cause of hyperaldosteronism. Overexpression of SF-1 has been extensively studied, but little in-depth information is available regarding the effects of inhibitory SF-1 on CYP11B2 and Ang II. In this paper, we have investigated the roles of down-regulated SF-1 in basal and Ang II-induced CYP11B2 expression using SF-1-specific short hairpin RNA. Inhibitory SF-1 was found to decrease the sensitivity of CYP11B2 and aldosterone to Ang II stimulation, whereas a down-regulation of SF-1 enhanced basal CYP11B2 expression and aldosterone production in H295R cells. Considering these differential effects of SF-1 on aldosterone production, these results might provide a new insight into the understanding of hyperaldosteronism.