The enzyme 6-phospho-β-glucosidase is an important member of the glycoside hydrolase family 1 (GH1). However, its catalytic mechanisms, especially the key residues determining substrate specificity and affinity, are poorly understood. A metagenome-derived gene sequence, encoding a novel 6-phospho-β-glucosidase designated Pbgl25-217, was isolated and characterized. The optimal conditions for enzymatic activity were 37°C and pH 7; Ca2+, Mg2+, and Mn2+ stabilized the activity of Pbgl25-217, whereas Ni2+, Fe2+, Zn2+, Cu2+, and Fe3+ inhibited its activity. The Km and Vmax of Pbgl25-217 were 4.8 mM and 1,987.0 U mg−1, respectively. Seven conserved residues were recognized by multiple alignments and were tested by site-directed mutagenesis for their functions in substrate recognition and catalytic reaction. The results suggest that residues S427, Lys435, and Tyr437 act as “gatekeepers” in a phosphate-binding loop and play important roles in phosphate recognition. This functional identification may provide insights into the specificity of 6-phospho-β-glycosidases in GH1 and be useful for designing further directed evolution.
Racial/ethnic and socioeconomic disparities regarding untreated oral disease exist for older adults, and poor oral health diminishes quality of life. The ElderSmile program integrated screening for diabetes and hypertension into its community-based oral health activities at senior centers in northern Manhattan. Findings were that minority seniors were willing to be screened for primary care sensitive conditions by dental professionals, and a high level of unrecognized disease was found (7.8% and 24.6% of ElderSmile participants had positive screening results for previously undiagnosed diabetes and hypertension, respectively). Dental professionals may screen for primary care sensitive conditions and refer patients to health care providers for definitive diagnosis and treatment. The ElderSmile program is a replicable model for community-based oral and general health screening.
To investigate the effects of social isolation on oral mucosal healing in rats, and to determine if wound-associated genes and microRNAs (miRNAs) may contribute to this response.
Rats were group housed or socially isolated for 4 weeks before a 3.5 mm wound was placed on the hard oral palate. Wound closure was assessed daily and tissues were collected for determination of gene expression levels and miRNAs (i.e., miR-29a,b,c and miR-203). The predicted target of these microRNAs (i.e., vascular endothelial growth factor A, VEGFA) was functionally validated.
Social isolation stress delayed the healing process of oral palatal mucosal wounds in rats. Lower mRNA levels of interleukin-1β (IL1β), macrophage inflammatory protein-1α (MIP1α), fibroblast growth factor 7 (FGF7), and VEGFA were found in the biopsied tissues of isolated animals on days 1 and/or 3 post-wounding. Intriguingly, the isolated rats persistently exhibited higher levels of miR-29 family members and miR-203. Our results confirmed that VEGFA is a direct target of these miRNAs, as both miR-29a,c and miR-203 strongly and specifically suppressed endogenous VEGFA expression in vitro.
This study in rats demonstrates for the first time that social isolation delays oral mucosal healing, and suggests a potential role for healing-associated gene and miRNA interactions during this process via modulation of VEGF expression.
AIM: To investigate the effect of polydatin (PD), a resveratrol glucoside, on mast cell degranulation and anti-allergic activity.
METHODS: After the rats were orally sensitized with ovalbumin (OVA) for 48 d and underwent PD treatment for 4 d, all the rats were stimulated by 100 mg/mL OVA for 24 h and then sacrificed for the following experiments. The small intestines from all the groups were prepared for morphology examination by hematoxylin and eosin staining. We also used a smooth muscle organ bath to evaluate the motility of the small intestines. The OVA-specific immunoglobulin E (IgE) production and interleukin-4 (IL-4) levels in serum or supernatant of intestinal mucosa homogenates were analyzed by enzyme-linked immunosorbent assay (ELISA). Using toluidine blue stain, the activation and degranulation of isolated rat peritoneal mast cells (RPMCs) were analyzed. Release of histamine from RPMCs was measured by ELISA, and regulation of PD on intracellular Ca2+ mobilization was investigated by probing intracellular Ca2+ with fluo-4 fluorescent dye, with the signal recorded and analyzed.
RESULTS: We found that intragastric treatment with PD significantly reduced loss of mucosal barrier integrity in the small intestine. However, OVA-sensitization caused significant hyperactivity in the small intestine of allergic rats, which was attenuated by PD administration by 42% (1.26 ± 0.13 g vs OVA 2.18 ± 0.21 g, P < 0.01). PD therapy also inhibited IgE production (3.95 ± 0.53 ng/mL vs OVA 4.53 ± 0.52 ng/mL, P < 0.05) by suppressing the secretion of Th2-type cytokine, IL-4, by 34% (38.58 ± 4.41 pg/mL vs OVA 58.15 ± 6.24 pg/mL, P < 0.01). The ratio of degranulated mast cells, as indicated by vehicles (at least five) around the cells, dramatically increased in the OVA group by 5.5 fold (63.50% ± 15.51% vs phosphate-buffered saline 11.15% ± 8.26%, P < 0.001) and fell by 65% after PD treatment (21.95% ± 4.37% vs OVA 63.50% ± 15.51%, P < 0.001). PD mediated attenuation of mast cell degranulation was further confirmed by decreased histamine levels in both serum (5.98 ± 0.17 vs OVA 6.67 ± 0.12, P < 0.05) and intestinal mucosa homogenates (5.83 ± 0.91 vs OVA 7.35 ± 0.97, P < 0.05). Furthermore, we demonstrated that administration with PD significantly decreased mast cell degranulation due to reduced Ca2+ influx through store-operated calcium channels (SOCs) (2.35 ± 0.39 vs OVA 3.51 ± 0.38, P < 0.01).
CONCLUSION: Taken together, our data indicate that PD stabilizes mast cells by suppressing intracellular Ca2+ mobilization, mainly through inhibiting Ca2+ entry via SOCs, thus exerting a protective role against OVA-sensitized food allergy.
Polydatin; Food allergy; Mast cells; Store-operated calcium channels; Ca2+
Objective: All-trans retinoic acid (ATRA) has been demonstrated to inhibit tumor growth by restoration of gap junctional intercellular communication (GJIC) via upregulation of connexin (Cx) expression in some solid tumors. However, the relationship between ATRA and GJIC remains unclear in oral squamous cell carcinoma (OSCC). The aim of this study was to investigate the effect of ATRA on the GJIC function of OSCC.
Study design: We measured the effects of ATRA on the viability and cell cycle distribution of SCC9 and Tca8113 OSCC cells. The GJIC function was observed using the scrape-loading dye transfer technique, and the mRNA and protein levels of Cx32 and Cx43 were detected by qRT-PCR, Western blot, and immunofluorescence assays.
Results: ATRA inhibited the growth of OSCC cells in a dose- and time-dependent manner (P <0.05) and caused cell cycle arrest. ATRA-treated cells showed a 2.69-fold and 2.06-fold enhancement of GJIC in SCC9 and Tca8113 cells, respectively (P <0.05). Moreover, ATRA induced upregulation of Cx32 and Cx43 at both the mRNA and protein levels in OSCC cells.
Conclusion: Our results indicated that restoration of GJIC via enhanced Cx32 and Cx43 expression might serve as a novel mechanism for the anti-tumor effect of ATRA in OSCC.
Key words:All-trans retinoic acid, oral squamous cell carcinoma, connexin, gap junctional intercellular communication.
Coronary computed tomographic angiography (CCTA) is associated with high radiation dose to the female breasts. Bismuth breast shielding offers the potential to significantly reduce dose to the breasts and nearby organs, but the magnitude of this reduction and its impact on image quality and radiation dose have not been evaluated.
Radiation doses from CCTA to critical organs were determined using metal-oxide-semiconductor field-effect transistors positioned in a customized anthropomorphic whole-body dosimetry verification phantom. Image noise and signal were measured in regions of interest (ROIs) including the coronary arteries.
With bismuth shielding, breast radiation dose was reduced 46–57% depending on breast size and scanning technique, with more moderate dose reduction to the heart, lungs, and esophagus. However, shielding significantly decreased image signal (by 14.6 HU) and contrast (by 28.4 HU), modestly but significantly increased image noise in ROIs in locations of coronary arteries, and decreased contrast-to-noise ratio by 20.9%..
While bismuth breast shielding can significantly decrease radiation dose to critical organs, it is associated with an increase in image noise, decrease in contrast-to-noise, and changes tissue attenuation characteristics in the location of the coronary arteries.
coronary CT angiography; radiation dose; bismuth shielding; breast shielding
Caregivers may represent an opportunity to improve cardiovascular disease (CVD) outcomes but prospective data are limited. We studied 3188 consecutive patients [41% minority, 39% female] admitted to a university hospital medical cardiovascular service to evaluate the association between having a caregiver and rehospitalization/death at 1 year. Clinical outcomes at 1 year were documented by a hospital-based clinical information system supplemented by standardized questionnaire. Comorbidities were documented by hospital electronic record review. At baseline, 13% (n=417) of patients had a paid caregiver and 25% (n=789) had only an informal caregiver. Having a caregiver was associated with rehospitalization or death at 1 year (OR=1.68; 95%CI=1.45–1.95), which varied by paid (OR=2.46; 95%CI=1.96–3.09) and informal (OR=1.40; 95%CI=1.18–1.65) caregiver status. Having a caregiver was significantly (p<.05) associated with age ≥65 years, racial/ethnic minority, lack of health insurance, past medical history of diabetes mellitus or hypertension, a Ghali comorbidity index >1, chronic obstructive pulmonary disease, or taking ≥ 9 prescriptions medications. The relation between caregiving and rehospitalization/death at 1 year was attenuated, but remained significant after adjustment (Paid OR=1.64; 95%CI=1.26–2.12 and Informal OR=1.20; 95%CI=1.00–1.44). In conclusion, risk of rehospitalization/death was significantly higher among cardiac patients with caregivers and was not fully explained by traditional comorbidities. Systematic determination of having a caregiver may be a simple method to identify patients at heightened risk of poor clinical outcomes.
Cardiovascular Disease; Caregiving; Outcomes; Prevention
In selected patients undergoing cardiac surgery, our research group previously showed that optimized temporary biventricular pacing can increase cardiac output one hour after weaning from cardiopulmonary bypass. Whether pacing is effective after beating-heart surgery is unknown. Accordingly, in this study we examined the feasibility of temporary biventricular pacing after off-pump coronary artery bypass grafting.
The effects of optimized pacing on cardiac output were measured with an electromagnetic aortic flow probe at the conclusion of surgery in 5 patients with a preoperative mean left ventricular ejection fraction of 0.26 (range, 0.15–0.35). Atrioventricular (7) and interventricular (9) delay settings were optimized in randomized order.
Cardiac output with optimized biventricular pacing was 4.2 ± 0.7 L/min; in sinus rhythm, it was 3.8 ± 0.5 L/min. Atrial pacing at a matched heart rate resulted in cardiac output intermediate to that of sinus rhythm and biventricular pacing (4 ± 0.6 L/min). Optimization of atrioventricular and interventricular delay, in comparison with nominal settings, trended toward increased flow.
This study shows that temporary biventricular pacing is feasible in patients with preoperative left ventricular dysfunction who are undergoing off-pump coronary artery bypass grafting. Further study of the possible clinical benefits of this intervention is warranted.
Arrhythmias, cardiac/therapy; cardiac pacing, artificial/methods; cardiac output, low/therapy; heart failure/therapy; stroke volume; ventricular dysfunction, left/complications/prevention & control
Previous studies have demonstrated the efficacy of electroacupuncture at ST36 for patients with gastrointestinal motility disorders. While several lines of evidence suggest that the effect may involve vagal reflex, the precise molecular mechanism underlying this process still remains unclear. Here we report that the intragastric pressure increase induced by low frequency electric stimulation at ST36 was blocked by AP-5, an antagonist of N-methyl-D-aspartate receptors (NMDARs). Indeed, stimulating ST36 enhanced NMDAR-mediated, but not 2-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propanoic-acid-(AMPA-) receptor-(AMPAR-) mediated synaptic transmission in gastric-projecting neurons of the dorsal motor nucleus of the vagus (DMV). We also identified that suppression of presynaptic μ-opioid receptors may contribute to upregulation of NMDAR-mediated synaptic transmission induced by electroacupuncture at ST36. Furthermore, we determined that the glutamate-receptor-2a-(NR2A-) containing NMDARs are essential for NMDAR-mediated enhancement of gastric motility caused by stimulating ST36. Taken together, our results reveal an important role of NMDA receptors in mediating enhancement of gastric motility induced by stimulating ST36.
Several studies have indicated that PAPSS2 (3′-phosphoadenosine-5′-phosphosulfate synthetase 2) activity is important to normal skeletal development. Mouse PAPSS2 is predominantly expressed during the formation of the skeleton and cartilaginous elements of the mouse embryo and in newborn mice. However, the role and mechanism of PAPSS2 in bone formation remains largely unidentified. By analyzing the expression pattern of the PAPSS2 gene, we have found that PAPSS2 is expressed in bone tissue and bone formation. PAPSS2 transcripts increase during osteoblast differentiation and are in less level in RANKL-induced osteoclast like cells. By using lentivirus-mediated RNA interference (RNAi) technology, we knocked down PAPSS2 expression in MC3T3-E1 osteoblast. Silencing of PAPSS2 expression significantly decreases ALP activity and cell mineralization, inhibits expression of osteoblast marker osteopontin (OPN) and collagen I. Conversely, overexpression of PAPSS2 promotes the MC3T3-E1 to differentiate into osteoblast and mineralization. Moreover, compared to that in the control cells, the mRNA level and protein expression of phosphorylated Smad 2/3, which is a key transcriptional factor in the Smad osteoblast differentiation pathway, showed significant decreases in PAPSS2-silenced cells and increases in PAPSS2-overexpression cells. These results suggest that PAPSS2 might regulate osteoblast ALP activity and cell mineralization, probably through Smads signal pathways.
Two new drimenyl cyclohexenone derivatives, named purpurogemutantin (1) and purpurogemutantidin (2), and the known macrophorin A (3) were isolated from a bioactive mutant BD-1-6 obtained by random diethyl sulfate (DES) mutagenesis of a marine-derived Penicillium purpurogenum G59. Structures and absolute configurations of 1 and 2 were determined by extensive spectroscopic methods, especially 2D NMR and electronic circular dichroism (ECD) analysis. Possible biosynthetic pathways for 1–3 were also proposed and discussed. Compounds 1 and 2 significantly inhibited human cancer K562, HL-60, HeLa, BGC-823 and MCF-7 cells, and compound 3 also inhibited the K562 and HL-60 cells. Both bioassay and chemical analysis (HPLC, LC-ESIMS) demonstrated that the parent strain G59 did not produce 1–3, and that DES-induced mutation(s) in the mutant BD-1-6 activated some silent biosynthetic pathways in the parent strain G59, including one set for 1–3 production.
purpurogemutantin; purpurogemutantidin; sesquiterpene; meroterpenoid; structure determination; antitumor activity; Penicillium purpurogenum; marine-derived fungus; DES mutagenesis
A large number of studies have been conducted to explore the efficacy of electroacupuncture (EA) for the treatment of gastrointestinal motility. While several lines of evidence addressed the basic mechanism of EA on gastrointestinal motility regarding effects of limb and abdomen points, the mechanism for effects of the back points on gastric motility still remains unclear. Here we report that the NMDA receptor (NMDAR) antagonist kynurenic acid inhibited the gastric emptying increase induced by high-intensity EA at BL21 and agonist NMDA enhanced the effect of the same treatment. EA at BL21 enhanced NMDAR, but not AMPA receptor (AMPAR) component of miniature excitatory postsynaptic current (mEPSC) in gastric-projecting neurons of the dorsal motor nucleus of the vagus (DMV). In sum, our data demonstrate an important role of NMDAR-mediated synaptic transmission of gastric-projecting DMV neurons in mediating EA at BL21-induced enhancement of gastric emptying.
Previous studies demonstrated that Alzheimer's disease was considered as the consequence produced by deficiency of Kidney essence. However, the mechanism underlying the symptoms also remains elusive. Here we report that spatial learning and memory, escape, and swimming capacities were damaged significantly in Kidney-yang deficiency rats. Indeed, both hippocampal Aβ40 and 42 increases in Kidney-yang deficiency contribute to the learning and memory impairments. Specifically, damage of synaptic plasticity is involved in the learning and memory impairment of Kidney-yang deficiency rats. We determined that the learning and memory damage in Kidney-yang deficiency due to synaptic plasticity impairment and increases of Aβ40 and 42 was not caused via NMDA receptor internalization induced by Aβ increase. β-Adrenergic receptor agonist can rescue the impaired long-term potential (LTP) in Kidney-yang rats. Taken together, our results suggest that spatial learning and memory inhibited in Kidney-yang deficiency might be induced by Aβ increase and the decrease of β2 receptor function in glia.
In-depth knowledge of bodily fluid phosphoproteomes, such as whole saliva, is limited. To better understand the whole saliva phosphoproteome, we generated a large-scale catalog of phosphorylated proteins. To circumvent the wide dynamic range of phosphoprotein abundance in whole saliva, we combined dynamic range compression using hexapeptide beads, strong cation exchange HPLC peptide fractionation, and immobilized metal affinity chromatography prior to mass spectrometry. In total, 217 unique phosphopeptides sites were identified representing 85 distinct phosphoproteins at 2.3% global FDR. From these peptides, 129 distinct phosphorylation sites were identified of which 57 were previously known, but only 11 of which had been previously identified in whole saliva. Cellular localization analysis revealed salivary phosphoproteins had a distribution similar to all known salivary proteins, but with less relative representation in “extracellular” and “plasma membrane” categories compared to salivary glycoproteins. Sequence alignment showed that phosphorylation occurred at acidic-directed kinase, proline-directed, and basophilic motifs. This differs from plasma phosphoproteins, which predominantly occur at Golgi casein kinase recognized sequences. Collectively, these results suggest diverse functions for salivary phosphoproteins and multiple kinases involved in their processing and secretion. In all, this study should lay groundwork for future elucidation of the functions of salivary protein phosphorylation.
Phosphoproteomics; Whole Saliva; Dynamic Range Compression; Mass Spectrometry
This paper addresses the dose-finding problem in cancer trials in which we are concerned with the gradation of severe toxicities that are considered dose limiting. In order to differentiate the tolerance for different toxicity types and grades, we propose a novel extension of the continual reassessment method that explicitly accounts for multiple toxicity constraints. We apply the proposed methods to redesign a bortezomib trial in lymphoma patients and compare their performance with that of the existing methods. Based on simulations, our proposed methods achieve comparable accuracy in identifying the maximum tolerated dose but have better control of the erroneous allocation and recommendation of an overdose.
Design calibration; Dose-finding cancer trials; Toxicity grades and types
To assess stability of cardiac output, mean arterial pressure, and systemic vascular resistance during biventricular pacing optimization.
Substudy analysis of data collected as part of a randomized controlled study examining the effects of optimized temporary biventricular pacing after cardiopulmonary bypass.
Single center study at a university affiliated tertiary care hospital.
Cardiac surgery patients at risk of left ventricular failure following cardiopulmonary bypass (CPB).
Biventricular pacing was optimized immediately after CPB. Atrioventricular delay (7 unique settings) was optimized first, followed by left ventricular pacing site (3 unique settings), followed by interventricular delay (9 unique settings) Each setting was tested twice for 10 seconds each time. Vasoactive medication and fluid infusion rates were held constant.
Measurements and Main Results
Aortic flow velocity and radial artery pressure were digitized, recorded, and averaged over single respiratory cycles. Least squares and linear regression/Wilcoxon analysis were applied to the first seven patients studied. Subsequently, curvilinear analysis was applied to 15 patients. Changes in MAP and SVR were statistically insignificant or too small to be meaningful by least squares analysis. During interventricular synchrony optimization, cardiac output and mean arterial pressure decreased (mean changes −5.7% and −2.5%, respectively; with standard errors 2.3% and 1.5%, respectively), whereas SVR increased (mean change 3.1% with standard error 3.4%). Only the change in cardiac output was statistically significant (p =0.043). Curvilinear fits to data for 15 patients demonstrate progressive hemodynamic stability over the total testing period.
BiVP optimization may be safely applied in patients following CPB. With continuous monitoring of MAP and CO the procedure results in no harmful hemodynamic perturbation.
Cardiac Function; Cardiopulmonary Bypass; Physiology; Pathophysiology; Circulatory Hemodynamics; Electrophysiology; Pacing; Cardiac Resynchronization Therapy; Biventricular Pacing
A new approach to activate silent gene clusters for dormant secondary metabolite production has been developed by introducing gentamicin-resistance to an originally inactive, marine-derived fungal strain Penicillium purpurogenum G59. Upon treatment of the G59 spores with a high concentration of gentamicin in aqueous DMSO, a total of 181 mutants were obtained by single colony isolation. In contrast to the strain G59, the EtOAc extracts of nine mutant cultures showed inhibitory effects on K562 cells, indicating that the nine mutants had acquired capability to produce antitumor metabolites. This was evidenced by TLC and HPLC analysis of EtOAc extracts of G59 and the nine mutants. Further isolation and characterization demonstrated that four antitumor secondary metabolites, janthinone (1), fructigenine A (2), aspterric acid methyl ester (3) and citrinin (4), were newly produced by mutant 5-1-4 compared to the parent strain G59, and which were also not found in the secondary metabolites of other Penicillium purpurogenum strains. However, Compounds 1–4 inhibited the proliferation of K562 cells with inhibition rates of 34.6% (1), 60.8% (2), 31.7% (3) and 67.1% (4) at 100 μg/mL, respectively. The present study demonstrated the effectiveness of a simple, yet practical approach to activate the production of dormant fungal secondary metabolites by introducing acquired resistance to aminoglycoside antibiotics, which could be applied to the studies for eliciting dormant metabolic potential of fungi to obtain cryptic secondary metabolites.
Penicillium purpurogenum G59; marine-derived fungus; gentamicin resistance; DMSO; antitumor activity; secondary metabolite production
Interest in ion channels as drug targets for contraception has grown with the realization that certain ion channel subunits are located exclusively in sperm. Selective knockdown of ion channel subunits can lead to infertility without ill effects, and selective inhibitors and/or openers of these ion channels could interfere with sperm function. In this study, in vivo electroporation (EP) and rete testis microinjection-mediated plasmid DNA were adopted to silence CatSper2 expression, which is essential in sperm hyperactivation. The results showed that high transfection efficiency and expression were achieved by plasmid DNA that was directly injected into the rete testis. As a result of the expression of CatSper2 being blocked, the treatment group showed significantly lower (P<0.05) hyperactivation rate, fertilization rate in vitro, migration motility in viscoelastic solution and intracellular Ca2+ peak. The low hyperactivation and fertilization rates lasted for 60 days. Meanwhile, analysis of the sperm survival rate and testis histology indicated that in vivo EP had no significant effect on the function of the testis, spermatogenesis or sperm activity. The present study demonstrated that it was feasible to achieve male contraception by silencing the expression of CatSper2, the key protein involved in sperm hyperactivation.
Catsper2; in vivo electroporation; male contraception; rete testis microinjection
Objective. The chemokine receptor CXCR4 and its ligand CXCL12 have been suggested to play important roles in the initiation or progression of cancers. The goal of the present study was to investigate alterations of CXCL12/CXCR4 in oral premalignant lesions and oral squamous cell carcinoma (OSCC). Methods. In 13 normal oral epithelia, 24 dysplastic oral leukoplakia (OLK), and 40 OSCC specimens, expressions of CXCL12 and CXCR4 were evaluated by immunohistochemistry. Results. CXCR4 was expressed in 37.5% of OLK and 60% of OSCC. CXCL12 was detected in 50% of OLK and 62.5% of OSCC. In OLK, CXCR4 positive ratio showed no significant difference from normal epithelia, but the CXCL12 positive ratio was significantly higher. Significant relationship between CXCL12 and CXCR4 was found both in OLK and OSCC. Conclusion. Our results indicated that CXCL12/CXCR4 axis may play roles from early steps of oral malignant transformation and contribute to the progress of oral carcinogenesis.
Hepatitis B virus X protein (HBx) plays a crucial role in the development of hepatocellular carcinoma (HCC), however, little is known about the mechanism. Here, we investigated the relationship between HBx and Notch signaling in HepG2 cells after they were transfected with the HBx gene. It was found that HBx upregulated the expression of Notch-1, Jagged-1 and Hes-1 at the transcriptional level by binding to the Notch-1 intracellular domain, which is congruent with the observations of enhanced malignant biological activities of HBx-transfected HepG2 cells compared with normal HepG2 cells. However, while Notch signaling was blocked, the HBx-induced abnormalities were partially reversed. These findings suggest that HBx may promote the progression of HCC via the activated Notch pathway.
HBx; HepG2; Notch; NICD; DAPT
A link between periodontal infections and an increased risk for vascular disease has been demonstrated. Porphyromonas gingivalis, a major periodontal pathogen, localizes in human atherosclerotic plaques, accelerates atherosclerosis in animal models and modulates vascular cell function. The receptor for advanced glycation endproducts (RAGE) regulates vascular inflammation and atherogenesis. We hypothesized that RAGE is involved in P. gingivalis’s contribution to proatherogenic responses in vascular endothelial cells.
Methods and Results
Murine aortic endothelial cells (MAEC) were isolated from wild type C57BL/6 or RAGE−/− mice and were infected with P. gingivalis strain 381. P. gingivalis 381 infection significantly enhanced expression of RAGE in wild-type MAEC. Levels of proatherogenic advanced glycation endproducts (AGEs) and monocyte chemoattractant protein 1 (MCP-1) were significantly increased in wild-type MAEC following P. gingivalis 381 infection, but were unaffected in MAEC from RAGE−/− mice or in MAEC infected with DPG3, a fimbriae-deficient mutant of P. gingivalis 381. Consistent with a role for oxidative stress and an AGE-dependent activation of RAGE in this setting, both antioxidant treatment and AGE blockade significantly suppressed RAGE gene expression and RAGE and MCP-1 protein levels in P. gingivalis 381 infected human aortic endothelial cells (HAEC).
The present findings implicate for the first time the AGE-RAGE axis in the amplification of proatherogenic responses triggered by P. gingivalis in vascular endothelial cells.
RAGE; infection; P. gingivalis; periodontitis; endothelial cells; vascular inflammation; atherosclerosis
Previous studies showed that genetic deletion or pharmacological blockade of the receptor for advanced glycation end products (RAGE) prevents the early structural changes in the glomerulus associated with diabetic nephropathy. To overcome limitations of mouse models that lack the progressive glomerulosclerosis observed in humans, we studied the contribution of RAGE to diabetic nephropathy in the OVE26 type 1 mouse, a model of progressive glomerulosclerosis and decline of renal function.
RESEARCH DESIGN AND METHODS
We bred OVE26 mice with homozygous RAGE knockout (RKO) mice and examined structural changes associated with diabetic nephropathy and used inulin clearance studies and albumin:creatinine measurements to assess renal function. Transcriptional changes in the Tgf-β1 and plasminogen activator inhibitor 1 gene products were measured to investigate mechanisms underlying accumulation of mesangial matrix in OVE26 mice.
Deletion of RAGE in OVE26 mice reduced nephromegaly, mesangial sclerosis, cast formation, glomerular basement membrane thickening, podocyte effacement, and albuminuria. The significant 29% reduction in glomerular filtration rate observed in OVE26 mice was completely prevented by deletion of RAGE. Increased transcription of the genes for plasminogen activator inhibitor 1, Tgf-β1, Tgf-β–induced, and α1-(IV) collagen observed in OVE26 renal cortex was significantly reduced in OVE26 RKO kidney cortex. ROCK1 activity was significantly lower in OVE26 RKO compared with OVE26 kidney cortex.
These data provide compelling evidence for critical roles for RAGE in the pathogenesis of diabetic nephropathy and suggest that strategies targeting RAGE in long-term diabetes may prevent loss of renal function.
Purpose: Patients with acute hip fractures who are on maintenance warfarin for anticoagulation present a significant challenge and their management remains controversial. The purpose of this study was to assess thromboembolic and systemic complications associated with pharmacological reversal of warfarin-associated coagulopathy in a population of geriatric patients with hip fractures. Methods: This retrospective cohort study identified patients with operative hip fractures on oral warfarin therapy who had an international normalized ratio (INR) >1.50 on admission (N = 93) approximately over a 13-year span. The control group consisted of patients whose warfarin was held upon admission without further intervention preoperatively (n = 23). The treatment group consisted of patients who underwent pharmacologic reversal of elevated INR with vitamin K and/or fresh frozen plasma (FFP) in addition to holding warfarin (n = 70). Primary outcomes included thromboembolic and other complications as well as mortality within 3 months of presentation. Time to surgery was a secondary outcome. Results: The 3-month mortality rate was 4% in the pharmacological intervention group and 17% in the watch-and-wait group; this difference trended toward statistical significance (P = .06). There were no significant differences in the likelihoods of other thromboembolic or nonthromboembolic complications between groups. While the difference in mean time to surgery was not significantly different overall between groups, this difference was significant in a subgroup of patients with higher baseline INRs (n = 46, INR >2.17), with a mean difference of 4.0 fewer days until surgery in the pharmacological intervention group (P < .01). Conclusions: Pharmacological reversal of warfarin-associated coagulopathy with a combination of vitamin K and FFP appears to be a safe way to optimize patients for operative fixation of hip fractures and is associated with a shorter delay to surgery in patients with more elevated INRs preoperatively. Level of evidence: retrospective cohort study (level III).
anticoagulation; warfarin; reversal; hip fracture
A quantitative structure–property relationship (QSPR) analysis of aliphatic alcohols is presented. Four physicochemical properties were studied: boiling point (BP), n-octanol–water partition coefficient (lg POW), water solubility (lg W) and the chromatographic retention indices (RI) on different polar stationary phases. In order to investigate the quantitative structure–property relationship of aliphatic alcohols, the molecular structure ROH is divided into two parts, R and OH to generate structural parameter. It was proposed that the property is affected by three main factors for aliphatic alcohols, alkyl group R, substituted group OH, and interaction between R and OH. On the basis of the polarizability effect index (PEI), previously developed by Cao, the novel molecular polarizability effect index (MPEI) combined with odd-even index (OEI), the sum eigenvalues of bond-connecting matrix (SX1CH) previously developed in our team, were used to predict the property of aliphatic alcohols. The sets of molecular descriptors were derived directly from the structure of the compounds based on graph theory. QSPR models were generated using only calculated descriptors and multiple linear regression techniques. These QSPR models showed high values of multiple correlation coefficient (R > 0.99) and Fisher-ratio statistics. The leave-one-out cross-validation demonstrated the final models to be statistically significant and reliable.
quantitative structure property relationship; aliphatic alcohols; boiling points; n-octanol-water partition coefficient; water solubility; retention indices
The aim of this study was to evaluate the clinical and radiographic results of cementless acetabular revision with deep frozen morsellised allografts. Sixty-one patients (65 hips) underwent acetabular revision using cementless components and deep frozen morsellised allografts. Fifty-seven hips (53 patients) were reviewed at a mean of 105.1 months (range 72–180 months) after revision. The study group included 29 males and 24 females with a mean age of 46.4 years. One cup underwent further revision for aseptic loosening and two were defined as radiographic failures. The mean time for allograft incorporation was 12.5 months (range 6–24 months) after index surgery. The mean Harris hip score of the patients improved from 61.1 points preoperatively to 91.6 points postoperatively. Linear and cavitary osteolysis was observed in two and 12 hips, respectively. The acetabular revision using cementless components with deep frozen morsellized allografts provides favourable clinical and radiographic results, although the initial disease and age may adversely affect the outcomes.