Fracture toughness of various core build-up materials

PURPOSE: The purpose of this investigation was to compare the fracture toughness of several core materials. MATERIALS AND METHODS: Five core build-up materials were tested: (1) glass ionomer, (2) resin-modified glass ionomer, (3) titanium-reinforced composite, (4) composite resin with fluoride, and (5) amalgam. Fracture toughness determinations were made using 3-point flexure of beams with a central single-edge notch. The notch was standardized by the use of a special mold into which each of the materials was condensed. Ten beams of each material were tested on an Instron test machine (Instron Corp, Canton, MA) at a crosshead speed of 1.25 mm/min. The maximum loads were determined from which the fracture toughness values (KIC) were calculated. The data were analyzed statistically using analysis of variance and t tests. RESULTS: The mean fracture toughness value in MN.m-3/2 for each of them is as follows: (1) glass ionomer, 0.717 +/- 0.071; (2) resin-modified glass ionomer, 0.747 +/- 0.061; (3) titanium-reinforced composite, 1.409 +/- 0.051; (4) composite resin with fluoride, 1.660 +/- 0.086; and (5) amalgam, 1.521 +/- 0.081. There was no significant difference in the KIC values for the glass ionomer-based materials, and both of these were significantly lower than amalgam, titanium-reinforced composite resin, and composite resin with fluoride (p < .001). CONCLUSION: The titanium-reinforced composite resin, the composite resin with fluoride, and amalgam materials showed fracture toughness most likely to withstand the stresses generated during mastication.     

Effect of Electro-acupuncture on Expression of IRS-1/PI3K/GLUT4 Pathway in Ovarian Granulosa Cells of Infertile Patients with Polycystic Ovary Syndrome-Insulin Resistance of Phlegm-Dampness Syndrome

Objective: To evaluate the effect of electro-acupuncture (EA) in infertile patients with phlegm dampness polycystic ovary syndrome-insulin resistance (PCOS-IR). Methods: Seventy-six PCOS-IR patients who underwnet in vitro fertilization and embryo transfer (IVF-ET) were equally assigned to two groups according to a random digital table: the EA group and the control group, with 38 cases in each group. Before undergoing IVF, the two groups were treated with EA or pseudo-acupuncture, respectively, for 3 menstrual cycles. The intervention was 25 min twice a week until the day of oocyte collection. The selected acupoints were Zhongwan (RN 12), Tianshu (ST 25), Daheng (SP 15), Daimai (GB 26), Qihai (CV 6), Guanyuan (CV 4), and bilateral points including Xuehai (SP 10), Fenglong (ST 40), Zusanli (ST 36), and Yinlingquan (SP 9). Evaluation of phlegm-dampness syndrome score and IR score were carried out before and after treatment. Additionally, the number of oocytes retrieved, transplantable embryo rate, high-quality embryo rate, clinical pregnancy rate and live birth rate were compared between the two groups. Real-time polymerase chain reaction analysis was used to monitor the mRNA expression of the insulin receptor substrate (IRS-1), phosphatidylinositiol 3-kinase (PI3K) and glucose transport factor 4 (GLUT4) in ovarian granulosa cells. Results: EA treatment reduced the phlegm-dampness syndrome score as well as the IR scores compared with the control group (P<0.05). No significant differences in the number of oocytes retrieved and clinical pregnancy rate between the two groups (P>0.05). Moreover, the transplantable embryo rate [49.0% (284/580) vs. 41.9% (273/652)], high-quality embryo rate [36.6% (104/284) vs. 27.8% (76/273)], and live birth rate [50% (19/38) vs. 26.3% (10/38)] in the EA group were significantly higher than in the control group (P<0.05). Gene expression analyses revealed significantly elevated IRS-1, PI3K and GLUT4 mRNA in ovarian granulosa cells of the EA group compared with the control group (P<0.05). Conclusions: EA may ameliorate the effects of phlegm-dampness syndrome and ovarian IR in PCOS-IR patients. Mechanistically, this effect might be through an upregulation of the IRS-1/PI3K/GLUT4 signaling pathway, which may result in improved oocyte quality and embryonic development potential. (Registration No. ChiCTR1800015453)     

Comparative Study of the Genetic Diversity,Antimicrobial Resistance,and Pathogenicity of Aeromonas Isolates from Clinical Patients and Healthy Individuals

Objective This study was performed to compare the genetic diversity, virulence, and antimicrobial resistance of Aeromonas strains isolated from patients and healthy individuals. Methods A total of 38 clinical strains and 19 strains from healthy individuals were isolated from the samples collected in Ma'anshan City, Anhui Province. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, and their resistance to 12 antibiotics was evaluated. The pathogenicity of these strains was examined through beta-hemolysis, protease activity, and virulence gene assays. Results The 57 Aeromonas strains were divided into 55 sequence types. Of these types, 21 were novel, suggesting that their genetic diversity was high. These Aeromonas isolates could be divided into 7 species, and the positive rates of beta-hemolysis and protease activity were 49.1％ and 73.7％, respectively. The detection rate of clinical patients in terms of beta-hemolysis and protease activity was higher than that of healthy individuals. Among the four most common Aeromonas strains, A. dhakensis had the highest detection rate of virulence genes. The multidrug resistance rate of the clinical isolates was much higher than that of the strains isolated from healthy individuals. Conclusions The taxonomy, virulence properties, and antibiotic resistance of Aeromonas isolates from patients differ from those of the isolates from healthy individuals.     

Improvement in Quality of Life With Left Prefrontal Transcranial Magnetic Stimulation in Patients With Pharmacoresistant Major Depression: Acute and Six Month Outcomes

BackgroundTranscranial magnetic stimulation (TMS) is a safe and effective treatment for major depression. We describe quality of life (QOL) outcomes from acute treatment with TMS, and describe the durability of benefit across 24-weeks.MethodsThree hundred and one medication-free patients with pharmacoresistant major depression were randomized to active or sham TMS in a 6-week controlled trial. Nonresponders to the 6-week blinded phase of the study were enrolled in a 6-week open-label study without unblinding the prior treatment assignment. Responders and partial responders to both the blinded (active or sham treatment) or open acute treatment phases were tapered off TMS over three weeks, while initiating maintenance antidepressant medication monotherapy. These subjects entered the 24-week study to examine the durability of response to TMS. The Medical Outcomes Study-36 Item Short Form (SF-36) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) were used to measure overall function and QOL. During the 24-week durability of effect study, QOL assessments were done at study entry and at the end of 24-weeks.ResultsStatistically significant improvement in both functional status and QOL outcomes was observed in patients treated with active TMS compared with sham TMS during the acute phase of the randomized, sham-controlled trial. Similar benefits were observed in patients who entered the open-label extension study. These improvements were sustained across the 24-week follow up study.ConclusionsAcute treatment with TMS improved functional status and QOL outcomes in patients with major depression. This clinical effect was durable in long-term follow up.     

Prevention and treatment of type 2 diabetes: current role of lifestyle, natural product, and pharmacological interventions

Common complications of type 2 diabetes (T2D) are eye, kidney and nerve diseases, as well as an increased risk for the development of cardiovascular disease and cancer. The overwhelming influence of these conditions contributes to a decreased quality of life and life span, as well as significant economic consequences. Although obesity once served as a surrogate marker for the risk of T2D, we know now that excess adipose tissue secretes inflammatory cytokines that left unchecked, accelerate the progression to insulin resistance and T2D. In addition, excess alcohol consumption may also increase the risk of T2D. From a therapeutic standpoint, lifestyle interventions such as dietary modification and/or exercise training have been shown to improve glucose homeostasis but may not normalize the disease process unless weight loss is achieved and increased physical activity patterns are established. Furthermore, utilization of natural products may serve as a significant adjunct in the fight against insulin resistance but further research is needed to ascertain their validity. Since it is clear that pharmaceutical therapy plays a significant role in the treatment of insulin resistance, this review will also discuss some of the newly developed pharmaceutical therapies that may work in conjunction with lifestyle interventions, and lessen the burden of behavioral change as the only strategy against the development of T2D.     

Vitamin D levels and obstructive sleep apnoea in children

Aims/hypothesisObstructive sleep apnoea (OSA) is a common health problem in children. African American (AA) and obese children have higher prevalence of OSA, and are also at a higher risk of reduced vitamin D levels. We hypothesised that OSA would be associated with lower levels of plasma 25-hydroxyvitamin D (25(OH)D) and increase in the risk of metabolic dysfunction and systemic inflammation.MethodsIn this observational cross-sectional study, 176 prospectively recruited children (mean age: 6.8 ± 0.8 years) underwent overnight polysomnographic evaluation and a fasting blood draw the morning after the sleep study. In addition to lipid profile, homeostatic model of insulin resistance (HOMA-IR) and high-sensitivity C-reactive protein (hsCRP) assays and plasma 25(OH)D levels were assessed using ELISA kits.ResultsAA children, obese children and children with OSA had significantly lower 25(OH)D levels. Linear associations emerged between 25(OH)D plasma levels and body mass index (BMI) z-score, hsCRP and HOMA-IR, as well as with apnoea–hypopnoea index (AHI) and oxygen saturation (SpO₂) nadir, the latter two associations remaining statistically significant even when controlling for all other potential confounders, and independently accounting for 17.7% of the variance in 25(OH)D (p < 0.01).Conclusions25(OH)D levels are reduced in paediatric OSA, in AA children and in obese children, particularly when all are present, and may play a role in modulating the degree of insulin resistance and systemic inflammation. The short-term and long-term significance of reduced 25(OH)D in paediatric OSA remains undefined.     

VAMP加逆转剂治疗难治性急性淋巴细胞白血病的体内、外研究

目的：观察VAMP方案加维拉帕米或环孢菌素A逆转治疗难治性ALL的疗效。方法：选择原发和继发耐药的ALL患者13例，采用VAMP方案加维拉帕米或环孢菌素A逆转体内、外研究。结果：13例ALL中7例达CR,3例达PR,3例无效。体外VAMP方案加VRP或CsA可有效逆转耐药。结论：采用VAMP方案加维拉帕米或环孢菌素A逆转治疗难治性ALL,可取得较好的疗效,为争取移植治疗创造了条件。