Antimony glasses with large nonlinear refractive indices, small two-photon absorption coefficients and ultrafast response at telecom wavelengths

Nonlinear (NL) optical properties of antimony oxide based glasses (AG) were characterized for excitation wavelengths from 800 to 1600 m. The NL refractive indices, n2, and the two-photon absorption (TPA) coefficient, β, have been evaluated using the Z-scan technique. Values of n2≈ 10-15 - 10-14 cm2/W of electronic origin were measured and negligible TPA coefficients (β < 0.003 cm/GW) were determined. The response time of the nonlinearity is faster than 100 fs as determined using the Kerr shutter technique. The figure-of-merit usually considered for all-optical switching, T = 2βλ/n2 , indicates that AG are very good materials for ultrafast switches at telecom wavelengths. © 2007 IEEE.

Citotoxicity and immune response induced by organopalladium(II) compounds in mice bearing Ehrlich ascites tumour

Cyclometallated palladium(II) complexes are reactive inorganic compounds employed in several biological studies because of their antitumour potential and interaction with immune system. In the present study, the immune and citotoxic response induced by two organopalladated complexes: [{Pd(N,C-dmba)} 2(μ-NCS) 2] (1), [Pd(C-dmba)(NCS)(dppp)] (2) [dmba = N,N′-dimethylbenzylamine, dppp = 1,3-bis(diphenylphosphino)propane] and cisplatin (cis-DDP), as standard, were investigated in mice bearing Ehrlich ascites tumour. The mice were divided into five groups and inoculated with the compounds (1) or (2) or cisplatin, or only vehicle or phosphate-buffered saline (PBS). Many parameters were evaluated, such as tumour cell percentage in the peritoneal exsudate, levels of seric nitric oxide (NO) and tumour necrosis factor-alpha (TNF-α) and increase in life span. Analysis of all data revealed, for compound (2), an activity similar to that presented by cisplatin, resulting in increased life span, lower levels of seric TNF-α and increase in NO production. ©2007 Sociedade Brasileira de Química.

Response of human dental pulp capped with MTA and calcium hydroxide powder

Objectives: To compare the response of human dental pulp capped with a mineral trioxide aggregate (MTA) and Ca(OH) 2 powder. Methods and Material: Pulp exposures were performed on the occlusal floor of 40 permanent premolars. The pulp was then capped with either Ca(OH) 2 powder (CH) or MTA and restored with resin composite. After 30 days (groups CH30 and MTA30) and 60 days (groups CH60 and MTA60), the teeth were extracted and processed for HE and categorized in a histological score system. The data were subjected to Kruskal-Wallis and Conover tests (α=0.05). Results: In regard to dentin bridge formation, CH30 showed a tendency towards superior performance compared to MTA30 (p>0.05), although the products showed comparable results at day 60. In the item Inflammation and General State of the Pulp (p>0.05), CH showed a tendency towards presenting a higher inflammatory response. In the item Other Pulpal Findings, MTA and Ca(OH) 2 showed equal and excellent performance after 30 and 60 days (p>0.05). Conclusion: After 30 days, Ca(OH) 2 powder covered with calcium hydroxide cement showed faster hard tissue bridge formation compared to MTA. After 60 days, Ca(OH) 2 powder or MTA materials showed a similar and excellent histological response with the formation of a hard tissue bridge in almost all cases with low inflammatory infiltrate. © Operative Dentistry, 2008.

Performance of the CMS hadron calorimeter with cosmic ray muons and LHC beam data

The CMS Hadron Calorimeter in the barrel, endcap and forward regions is fully commissioned. Cosmic ray data were taken with and without magnetic field at the surface hall and after installation in the experimental hall, hundred meters underground. Various measurements were also performed during the few days of beam in the LHC in September 2008. Calibration parameters were extracted, and the energy response of the HCAL determined from test beam data has been checked. © 2010 IOP Publishing Ltd and SISSA.

Functional activity of neutrophils and systemic inflammatory response of Down's syndrome patients with periodontal disease

Periodontal disease (PD) is characterized as an inflammatory process that compromises the support and protection of the periodontium. Patients with Down's syndrome (DS) are prone to develop PD. Neutrophils (NE) are the first line of defense against infection and their absence sets the stage for disease. Aim: To compare the activity and function of NE in the peripheral blood from DS patients with and without PD, assisted at the Center for Dental Assistance to Patients with Special Needs affiliated with the School of Dentistry of Araçatuba, Brazil. Methods: Purified NE were collected from peripheral blood of 22 DS patients. NE were used to detect the 5-lypoxigenase (5-LO) expression by RT-PCR. Plasma from peripheral blood was collected to measure tumor necrosis factor-a (TNF-α) and interleukin-8 (IL-8) by ELISA and nitrite (NO 3) using a Griess assay. Results: Data analysis demonstrated that DS patients with PD present high levels of TNF-a and IL-8 when compared with DS patients without PD. However, there was no statistically significant difference in the levels of NO 3 production between the groups. The levels of the inflammatory mediator 5-LO expression increased in DS patients with PD. Conclusions: According with these results, it was concluded that TNF-α and IL-8 are produced by DS patients with PD. Furthermore, DS patients with PD presented high levels of 5-LO expression, suggesting the presence of leukotriene B 4 (LTB 4) in PD, thus demonstrating that the changes in NE function due to the elevation of inflammatory mediators contribute to PD.

Mathematical analysis and simulations involving chemotherapy and surgery on large human tumours under a suitable cell-kill functional response

Dosage and frequency of treatment schedules are important for successful chemotherapy. However, in this work we argue that cell-kill response and tumoral growth should not be seen as separate and therefore are essential in a mathematical cancer model. This paper presents a mathematical model for sequencing of cancer chemotherapy and surgery. Our purpose is to investigate treatments for large human tumours considering a suitable cell-kill dynamics. We use some biological and pharmacological data in a numerical approach, where drug administration occurs in cycles (periodic infusion) and surgery is performed instantaneously. Moreover, we also present an analysis of stability for a chemotherapeutic model with continuous drug administration. According to Norton & Simon [22], our results indicate that chemotherapy is less eficient in treating tumours that have reached a plateau level of growing and that a combination with surgical treatment can provide better outcomes.

Intensified peginterferon α-2a dosing increases sustained virologic response rates in heavy, high viral load hepatitis c genotype 1 patients with high low-density lipoprotein

BACKGROUND AND GOAL: Patients infected with hepatitis C virus (HCV) with elevated low-density lipoprotein (LDL) levels achieve higher sustained virologic response (SVR) rates after peginterferon (PegIFN)/ribavirin treatment versus patients with lower LDL. Our aim was to determine whether SVR rates in patients with low/elevated LDL can be improved by dose intensification. STUDY: In PROGRESS, genotype 1 patients with baseline HCV RNA≥400,000 IU/mL and body weight ≥85 kg were randomized to 48 weeks of 180 μg/wk PegIFN α-2a (40 kDa) plus ribavirin (A: 1200 mg/d; B: 1400/1600 mg/d) or 12 weeks of 360 μg/wk PegIFN α-2a followed by 36 weeks of 180 μg/wk, plus ribavirin (C: 1200 mg/d; D: 1400/1600 mg/d). This retrospective analysis assessed SVR rates among patients with low (<100 mg/dL) or elevated (≥100 mg/dL) LDL. Patients with high LDL (n=256) had higher baseline HCV RNA (5.86×10 IU/mL) versus patients with low LDL (n=262; 4.02×10 IU/mL; P=0.0003). RESULTS: Multiple logistic regression analysis identified a significant interaction between PegIFN α-2a dose and LDL levels on SVR (P=0.0193). The only treatment-related SVR predictor in the nested multiple logistic regression was PegIFN α-2a dose among patients with elevated LDL (P=0.0074); therefore, data from the standard (A+B) and induction (C+D) dose arms were pooled. Among patients with low LDL, SVR rates were 40% and 35% in the standard and induction-dose groups, respectively; SVR rates in patients with high LDL were 44% and 60% (P=0.014), respectively. CONCLUSIONS: Intensified dosing of PegIFN α-2a increases SVR rates in patients with elevated LDL even with the difficult-to-cure characteristics of genotype 1, high baseline viral load, and high body weight. Copyright © 2013 by Lippincott Williams & Wilkins.

Ionotropic but not metabotropic glutamatergic receptors in the locus coeruleus modulate the hypercapnic ventilatory response in unanaesthetized rats

Aim: Central chemoreceptors are important to detect changes of CO2/H+, and the Locus coeruleus (LC) is one of the many putative central chemoreceptor sites. Here, we studied the contribution of LC glutamatergic receptors on ventilatory, cardiovascular and thermal responses to hypercapnia. Methods: To this end, we determined pulmonary ventilation (VE), body temperatures (Tb), mean arterial pressure (MAP) and heart rate (HR) of male Wistar rats before and after unilateral microinjection of kynurenic acid (KY, an ionotropic glutamate receptor antagonist, 10 nmol/0.1 μL) or α-methyl-4-carboxyphenylglycine (MCPG, a metabotropic glutamate receptor antagonist, 10 nmol/0.1 μL) into the LC, followed by 60 min of air breathing or hypercapnia exposure (7% CO2). Results: Ventilatory response to hypercapnia was higher in animals treated with KY intra-LC (1918.7 ± 275.4) compared with the control group (1057.8 ± 213.9, P < 0.01). However, the MCPG treatment within the LC had no effect on the hypercapnia-induced hyperpnea. The cardiovascular and thermal controls were not affected by hypercapnia or by the injection of KY and MCPG in the LC. Conclusion: These data suggest that glutamate acting on ionotropic, but not metabotropic, receptors in the LC exerts an inhibitory modulation of hypercapnia-induced hyperpnea. © 2013 Scandinavian Physiological Society.

Alcohol Impairs Predation Risk Response and Communication in Zebrafish

The effects of ethanol exposure on Danio rerio have been studied from the perspectives of developmental biology and behavior. However, little is known about the effects of ethanol on the prey-predator relationship and chemical communication of predation risk. Here, we showed that visual contact with a predator triggers stress axis activation in zebrafish. We also observed a typical stress response in zebrafish receiving water from these conspecifics, indicating that these fish chemically communicate predation risk. Our work is the first to demonstrate how alcohol effects this prey-predator interaction. We showed for the first time that alcohol exposure completely blocks stress axis activation in both fish seeing the predator and in fish that come in indirect contact with a predator by receiving water from these conspecifics. Together with other research results and with the translational relevance of this fish species, our data points to zebrafish as a promising animal model to study human alcoholism. © 2013 Oliveira et al.

Salivary epithelial cells as model to study immune response against cutaneous pathogens

The human skin not only provides passive protection as a physical barrier against external injury, but also mediates active surveillance via epidermal cell surface receptors that recognize and respond to potential invaders. Primary keratinocytes and immortalized cell lines, the commonly used sources to investigate immune responses of cutaneous epithelium are often difficult to obtain and/or potentially exhibit changes in cellular genetic make-up. Here we investigated the possibility of using salivary epithelial cells (SEC) to evaluate the host response to cutaneous microbes. Elevated secretion of IFN-γ and IL-12 was observed in the SEC stimulated with Staphylococcus aureus, a transient pathogen of the skin, as mono species biofilm as compared to SEC stimulated with a commensal microbe, the Staphylococcus epidermidis. Co-culture of the SEC with both microbes as dual species biofilm elicited maximum cytokine response. Stimulation with S. aureus alone but not with S. epidermidis alone induced maximum toll-like receptor-2 (TLR-2) expression in the SEC. Exposure to dual species biofilm induced a sustained upregulation of TLR-2 in the SEC for up to an hour. The data support novel application of the SEC as efficient biospecimen that may be used to investigate personalized response to cutaneous microflora. © 2013 Wiley Periodicals, Inc.

Peginterferon plus ribavirin and sustained virological response rate in HCV-related advanced fibrosis: a real life study

Background: Tolerance and response to antiviral HCV treatment is poor in advanced fibrosis. The aim of this study was to assess SVR rate and its predictive factors in HCV advanced fibrosis patients treated in real life with full dose PEG-IFN plus RBV and to evaluate the adverse events related to treatment. Methods: A multicentric, retrospective study was conducted at six university hospitals. METAVIR F3 and F4 HCV monoinfected patients who were treated with PEG-IFN and RBV had their data analyzed. A stepwise logistic regression analysis was performed to identify the variables independently related to SVR. Adverse events were recorded during treatment. Results: 308 patients were included, 75% genotype 1 and 23% genotype 3. METAVIR F3 was present in 39% and F4 in 61% of patients. The median Child Pugh score for F4 patients was 5 (5–9). The global SVR rate was 34%, 11% were relapsers and 55% were nonresponders. SVR rates were similar between patients treated with PEG-IFN alfa 2a or alfa 2b (p = 0.24). SVR rates according to Child–Pugh score were 26% (Child A) and 18% (Child B). The independent factors related to SVR in F4 patients were genotype 3, RVR and fewer Child Pugh score points. Treatment interruption occurred in 31% patients and death occurred in 1.9%, all with liver cirrhosis. Conclusion: Treatment of HCV in patients with advanced fibrosis should not be postponed. However, a very careful evaluation of cirrhotic patients must be performed before treatment is indicated and careful monitoring is required during treatment.

Auditory stimulation with music influences the geometric indices of heart rate variability in response to the postural change maneuver

It is poor in the literature the behavior of the geometric indices of heart rate variability (HRV) during the musical auditory stimulation. The objective is to investigate the acute effects of classic musical auditory stimulation on the geometric indexes of HRV in women in response to the postural change maneuver (PCM). We evaluated 11 healthy women between 18 and 25 years old. We analyzed the following indices: Triangular index, Triangular interpolation of RR intervals and Poincar plot (standard deviation of the instantaneous variability of the beat-to beat heart rate [SD1], standard deviation of long-term continuous RR interval variability and Ratio between the short - and long-term variations of RR intervals [SD1/SD2] ratio). HRV was recorded at seated rest for 10 min. The women quickly stood up from a seated position in up to 3 s and remained standing still for 15 min. HRV was recorded at the following periods: Rest, 0-5 min, 5-10 min and 10-15 min during standing. In the second protocol, the subject was exposed to auditory musical stimulation (Pachelbel-Canon in D) for 10 min at seated position before standing position. Shapiro-Wilk to verify normality of data and ANOVA for repeated measures followed by the Bonferroni test for parametric variables and Friedmans followed by the Dunns posttest for non-parametric distributions. In the first protocol, all indices were reduced at 10-15 min after the volunteers stood up. In the protocol musical auditory stimulation, the SD1 index was reduced at 5-10 min after the volunteers stood up compared with the music period. The SD1/SD2 ratio was decreased at control and music period compared with 5-10 min after the volunteers stood up. Musical auditory stimulation attenuates the cardiac autonomic responses to the PCM.

In situ protocol for the detemination of dose-response effect of low-fluoride dentifrices on enamel remineralization

No in situ protocol has assessed the dose-response effects of fluoride dentifrices involving low-fluoride formulations. Objective: To assess the ability of an in situ remineralization model in determining dose-response effects of dentifrices containing low fluoride concentrations ([F]) on bovine enamel. Material and Methods: Volunteers wore palatal appliances containing demineralized enamel blocks and brushed their teeth and devices with the dentifrices supplied (double-blind, crossover protocol) separately for 3 and 7 days. Surface hardness (SH), integrated subsurface hardness (AKHN) and [F] in enamel were determined. Data were analyzed by ANOVA, Tukey's test and Pearson's correlation (p<0.05). Results: Dose-response relationships were verified between [F] in dentifrices and SH, AKHN and enamel [F]. Higher correlation coefficients between enamel [F] and SH and AKHN were obtained for the 3-day period. Significant differences in SH and AKHN were observed among all groups for the 3-day period, but not between 0-275, 275-550, and 550-1,100 mu g F/g dentifrices for the 7-day period, nor between 3- and 7-day periods for the 1,100 mu g F/g groups. Conclusions: Considering that the peak remineralization capacity of the conventional dentifrice (1,100 mu g F/g) was achieved in 3 days, this experimental period could be used in future studies assessing new dentifrice formulations, especially at low-fluoride concentrations.

Evaluation of the Host Response in Various Models of Induced Periodontal Disease in Mice

Background: The aim of this study is to characterize and evaluate the host response caused by three different models of experimental periodontitis in mice.Methods: C57BL/6 wild-type female mice were distributed into six experimental groups and sacrificed at 7, 15, and 30 days after the induction of periodontal disease: 1) group C: no treatment control group; 2) group L: periodontal disease induced by ligature; 3) group G-Pg: oral gavage with Porphyromonas gingivalis (Pg); 4) group G-PgFn: oral gavage with Fusobacterium nucleatum + Pg; 5) group I-Pg: heat-killed Pg injected into the palatal mucosa between the molars; and 6) group I-V: phosphatebuffered saline injected into the palatal mucosa. The samples were used to analyze the immune-inflammatory process in the gingival tissue via descriptive histologic and real-time polymerase chain reaction analyses. The alveolar bone loss was evaluated using microcomputed tomography. The data were analyzed using the Kruskal-Wallis test, followed by a post hoc Dunn test and analysis of variance, followed by a Tukey test using a 5% significance level.Results: Only the ligature model displayed significant alveolar bone loss in the initial period (7 days), which was maintained with time. The group injected with heat-killed Pg displayed significant alveolar bone loss starting from day 15, which continued to progress with time (P < 0.05). A significant increase (P < 0.05) in the gene expression of proinflammatory cytokines (interleukin-6 and -1b) and proteins involved in osteoclastogenesis (receptor activator of nuclear factor-kB ligand and osteoprotegerin) was observed in the ligature group on day 7.Conclusion: The ligature and injection of heat-killed Pg models were the most representative of periodontal disease in humans, whereas the oral gavage models were not effective at inducing the disease under the experimental conditions.

Periodontopathogens levels and clinical response to periodontal therapy in individuals with the interleukin-4 haplotype associated with susceptibility to chronic periodontitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)