The Effects of One-Step Self-Etch Adhesives on the Induction of Oxidative Stress and Production of TGF-β1 and BMP-2 by Human Gingival Fibroblasts

The aim of this study was to evaluate and compare the effects of two self-etch adhesive materials on the induction of oxidative stress and production of transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2) by cultured human gingival fibroblasts (HGF). Inflammation-free attached gingiva was obtained from healthy donors under informed consent. Following 24- and 72-h exposure of HGF to two different elutes of the test materials, cell viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Lipid peroxidation, a major indicator of oxidative stress, was measured by the thiobarbituric acid reactive substance (TBARS) assay. TGF-β1 and BMP-2 levels in cell-free culture media were determined by enzyme-linked immunosorbent assay (ELISA). Cell viability of the test groups was significantly lower than those of control at 24 and 72 h (P < 0.001), but showed an increase at 72 h (P < 0.001). The TBARS levels of both test groups were significantly greater than that of control (P < 0.05), and displayed similar values at 72 h (P > 0.05). For both materials, the levels of TGF-β1 and BMP-2 were significantly greater than that of control (P < 0.05). Both test groups showed increased TGF-β1 levels. These results indicate that the tested self-etch adhesives might be capable of inducing production of TGF-β1 and BMP-2 in cultured HGF, despite their cytotoxic and oxidative stress-producing potential.     

D-Galactose injured neurogenesis in the hippocampus of adult mice

Abstract

Objectives: We studied the effects of the reactive oxygen species (ROS) on neural progenitor cell proliferation and survival in the dentate gyrus (DG).

Methods: The adult mice were treated with D-galactose for 7 weeks to mimic natural aging in mice. The level of malondialdehyde (MDA) and the activities of antioxidant enzymes in the serum were detected. Neurodegeneration and neurogenesis in the hippocampus were explored using terminal deoxynucleotidyltransferase-mediated UTP nick-end labeling (TUNEL) to detect the dying cells and bromodeoxyuridine (BrdU) was used to label the newly born cells.

Results: After the treatment of D-galactose, the level of MDA increased and the activities of the antioxidant enzyme decreased in the serum. TUNEL-positive cells significantly increased in the DG, CA1 and CA3 subfields. The BrdU-labeled proliferating cells and surviving cells in the DG decreased significantly in number after D-galactose treatment.

Discussion: D-Galactose induced the impairment of neurogenesis in the DG, which is similar to natural aging in mice. ROS accumulation as a result of D-galactose may be related to the decrease of neurogenesis in the DG.     

急性胰腺炎细胞免疫功能测定

目的　探讨急性胰腺炎（ＡＰ） 病人的细胞免疫状态。方法　对３７ 例急性胰腺炎患者和１０ 例健康成人的Ｔ 淋巴细胞亚群,Ｃ 反应蛋白（ＣＲＰ） 进行测定分析。结果　Ｔ淋巴细胞亚群中ＣＤ４ 阳性细胞百分比和ＣＤ４／ＣＤ８ 比值在重症急性胰腺炎（ＳＡＰ） 患者中下降明显。结论　ＡＰ 患者特别是ＳＡＰ 患者存在细胞免疫功能损害,免疫调节治疗可能对ＳＡＰ 患者有一定的作用。邱新光, 男,３６ 岁, 医学博士, 河南医科大学附一院外科,４５００５２ 　河南省郑州市建设东路１ 号秦兆寅,纪宗正, 黎一鸣, 西安医科大学第二附属医院外科,７１０００４ 　陕西省西安市西五路３６ 号     

Dengue virus related hemophagocytosis: a rare case report

Abstract

We describe a patient with bone marrow hemophagocytosis who had classic dengue fever associated with nasal bleeding and pancytopenia. The patient recovered with appropriate supportive care. A literature search shows fewer than 20 case reports of dengue related hemophagocytosis in the English literature. Our patient is an interesting case of dengue related hemophagocytic syndrome and adds an additional case to the literature. Clinicians should consider that the occurrence of hemophagocytosis in the appropriate geographical area could be due to dengue virus infection and present with pancytopenia.     

Intestinal Motility During Hypoxia and Reoxygenation in Vitro

Ischemia-reperfusion injury leads to profoundfunctional and structural alterations of thegastrointestinal tract. We developed an in vitro modelof reperfusion injury to study the changes in intestinal motility during hypoxia followed byreoxygenation. We recorded the spontaneous motoractivity of intestinal rings from the proximal mousejejunum, using force displacement transducers. Inaddition to the rhythmic contractions, we studied thecontractile response to transmural stimulation ofintrinsic nerves. During hypoxia, the frequency of thespontaneous contractions and the resting tensiondecreased. While 29% of the tissues still responded toneural stimulation after 15 min of hypoxia, electricalfield stimulation did not evoke any response after 60min of hypoxia. Reoxygenation resulted in a transient increase in the baseline tension and an initialnormalization of the spontaneous rhythmic contractions,which subsequently became irregular. The percentage oftissues that recovered their ability to respond to electrical field stimulation 10 min afterreoxygenation decreased from 100% after 15 min ofhypoxia to 47% after 60 min of hypoxia. Theadministration of the antioxidant glutathione preventedthe functional abnormalities seen 10 min after reoxygenation.The pharmacological inhibition of Cu,Zn superoxidedismutase exacerbated the functional reoxygenationdamage. Conversely, the overexpression of thisradical-scavenging enzyme in transgenic mice increased thelikelihood of functional recovery. Reoxygenation in acalciumfree solution also prevented prolonged functionaldamage of the muscle rings. We conclude thathypoxia-reoxygenation significantly alters intestinal motility. Thegeneration of reactive oxygen species and disruptions inthe calcium homeostasis play an important role in thepathogenesis of reoxygenation damage. Interventions that alter the intracellular redox state oraffect the secondary changes in the intracellularcalcium concentration can prevent or blunt the effectsof reoxygenation injury on intestinalmotility.     

Chemical Conjugation of Cowpea Mosaic Viruses with Reactive HPMA-Based Polymers

N-(2-Hydroxypropyl)methacrylamide (HPMA) co-polymers containing disulfide and carbonyl thiazolidine-2-thione (TT) reactive groups in their side-chains (pHPMA-TT) were used as reductively removable chemical modification of the surface of cowpea mosaic viruses (CPMV). CPMV was used in this study as a model particle for viral gene delivery. The co-polymer reaction with CPMV surfaces carried out in aqueous solution was evaluated by monitoring the changes in the weight-average molecular weight and hydrodynamic size of the viruses using light scattering methods. The reaction conditions were optimized. The surface modification of CPMV with pHPMA-TT under selected conditions (concentrations of a coating polymer (c _p) and NaCl) has not influenced the size distribution of the viral particles. The uncharged polymers bound to the viral surface via biodegradable S–S bonds can be fully removed by the exchange reaction with reductive dithiothreitol. To achieve optimal covering of viral surfaces, the positively charged reactive polymers (with or without biodegradable S–S bonds) should be applied at low concentrations (c _p=0.1–0.5 mg/ml) and in presence of NaCl (0.15 M).     

Oral estrogen replacement therapy increases forearm reactive hyperemia accompanied by increases in serum levels of nitric oxide in postmenopausal women

The present study sought to determine the correlation between the vasodilator response of forearm resistance vessels and the circulating levels of nitric oxide (NO) after the administration of oral estrogen for 12 weeks to postmenopausal women. We classified postmenopausal women into two groups: those treated with conjugated equine estrogen (0.625 mg daily) orally for 12 weeks (n = 24) or those who received no treatment (control group ,n = 8). Forearm blood flow was measured using strain-gauge plethysmography during hyperemia to evaluate endotheliumdependent vasodilation ,and after sublingual nitroglycerin administration to evaluate endothelium-independent vasodilation. Serum levels of nitrite/nitrate (metabolites of NO) and lipid parameters were measured. Basal forearm blood flow ,body weight and heart rate were similar in each group. After 12 weeks of estrogen administration ,the maximal forearm blood flow response during reactive hyperemia and the serum level of nitrite/nitrate each showed a significant increase from 26.9 ± 1.9 to 37.9 ± 3.5 ml/min per 100 ml tissue (p < 0.01) ,and from 25.2 ± 2.2 to 37.5 ± 3.7 μmol/l (p < 0.05) ,respectively. No increases were seen in controls. The changes in forearm blood flow after sublingual nitroglycerin were similar before and after 12 weeks of estrogen administration. The increase in maximal forearm blood flow with reactive hyperemia was significantly correlated with the increase in nitrite/nitrate in the group administered estrogen (r = 0.48 ,p < 0.05). There was no significant correlation between maximal forearm blood flow with reactive hyperemia ,nor any change in serum lipids ,blood pressure or other parameters. In conclusion ,the 12-week administration of oral estrogen increased forearm reactive hyperemia in postmenopausal women ,probably via an increase in the production of NO.     

Time Controlled Release of Arabinofuranosylcytosine (Ara-C) from Agarose Hydrogels using Layer-by-Layer Assembly: An In Vitro Study

Experimentally induced axonal regeneration is compromised by glial scar formation arising from leptomeningeal fibroblasts cells in and around the hydrogel scaffold implanted for nerve repair. Strategies are needed to prevent such fibroblastic reactive cell layer formation for enhanced axonal regeneration. Here, we implement the technique of layer-by-layer assembled degradable, hydrogen bonded multilayers on agarose hydrogels to incorporate an anti-mitotic drug (1-β-D-arabinofuranosylcytosine (Ara-C)) within the agarose hydrogels. We show controlled release of Ara-C under physiological conditions over a period of days. The concentrations of Ara-C released from agarose at the different time points were sufficient to inhibit fibroblast growth in vitro, while not adversely affecting the viability of the neuronal cells.     

Evaluation of New Tri-methacrylates as a Reactive Diluent in Root Canal Sealant

In this work, a novel tri-methacrylate oligomer, GPTEMA, with three long-branched chain structures was synthesized through the reaction of glycerol propoxylate triglycidyl ether (GPTE) and methacrylic acid. The structure of GPTEMA was confirmed by FT-IR, ¹H-NMR, gel-permeation chromatography (GPC) and element analysis. The GPTEMA was used to partially or completely replace TEGDMA as reactive diluent and applied in a root canal sealant system containing Bis-GMA. The effects of GPTEMA on the polymerization behavior of Bis-GMA/TEGDMA/GPTEMA co-polymer and properties of its polymerizing product were investigated. Polymerization shrinkage, double bond conversion, glass transition temperature, flexural strength, flexural modulus, water sorption and diffusion coefficient of the Bis-GMA/TEGDMA/GPTEMA co-polymer were measured. The results illustrated that the Bis-GMA/TEGDMA/GPTEMA co-polymer attained lower polymerization shrinkage and higher double bond conversion. However, its T _g, flexural strength and flexural modulus decreased with increasing content of GPTEMA, water sorption and diffusion coefficient increased with increasing content of GPTEMA.