Influence of systemic antibiotic therapy on the development and progression of induced apical periodontitis in Wistar rats.

The aim of this study was to investigate the influence of systemic antibiotic therapy on the development and progression of induced apical periodontitis (AP) in Wistar rats. Fifty-six rats were submitted to pulp exposure of the lower left first molar for the induction of AP. On the same day, intraperitoneal antibiotic therapy was administered once a day, for 15 days, until euthanasia. The groups were formed according to the different treatments (n = 8): C-control; GEN-treated with gentamicin (10 mg/Kg); AC-treated with amoxicillin (100 mg/Kg); MZ-treated with metronidazole (40 mg/Kg); AMP-treated with ampicillin (100 mg/Kg); AMC group-treated with amoxicillin + clavulanic acid (100 mg/kg); CLI-treated with clindamycin (60 mg/kg). After euthanasia, the jaws were collected and processed for (1) histological and histometric analysis using hematoxylin and eosin staining, (2) analysis of collagen fibers using Picrosirius Red staining and (3) bacteriological analysis using Brown-Brenn staining. The data were analyzed statistically (p < 0.05). AP induction was confirmed in all groups. The AMC group had the lower intensity of inflammatory infiltrate (p = 0.028) and less periapical bone resorption compared to control (p = 0.006). Regarding collagen maturation, PSR staining revealed a predominance of mature collagen fibers in all groups. The AC and AMC groups had the lower amount of mature fibers and the highest amount of immature fibers, compared to all other groups (p < 0.001). All groups showed bacterial contamination; however, the AC and AMC groups showed a lower extent of bacterial contamination compared to the control (p < 0.001). It can be concluded that systemic antibiotic therapy influences the development and progression of induced AP.

Oxidative stress-induced autonomous activation of the calcium/calmodulin-dependent kinase II involves disulfide formation in the regulatory domain.

Calcium/calmodulin-dependent protein kinase II δ (CaMKIIδ) has a pivotal role in cardiac signaling. Constitutive and deleterious CaMKII "autonomous" activation is induced by oxidative stress, and the previously reported mechanism involves oxidation of methionine residues in the regulatory domain. Here, we demonstrate that covalent oxidation leads to a disulfide bond with Cys273 in the regulatory domain causing autonomous activity. Autonomous activation was induced by treating CaMKII with diamide or histamine chloramine, two thiol-oxidizing agents. Autonomy was reversed when the protein was incubated with DTT or thioredoxin to reduce disulfide bonds. Tryptic mapping of the activated CaMKII revealed formation of a disulfide between Cys273 and Cys290 in the regulatory domain. We determined the apparent pKa of those Cys and found that Cys273 had a low pKa while that of Cys290 was elevated. The low pKa of Cys273 facilitates oxidation of its thiol to the sulfenic acid at physiological pH. The reactive sulfenic acid then attacks the thiol of Cys290 to form the disulfide. The previously reported CaMKII mutant in which methionine residues 281 and 282 were mutated to valine (MMVV) protects mice and flies from cardiac decompensation induced by oxidative stress. Our initial hypothesis was that the MMVV mutant underwent a conformational change that prevented disulfide formation and autonomous activation. However, we found that the thiol-oxidizing agents induced autonomy in the MMVV mutant and that the mutant undergoes rapid degradation by the cell, potentially preventing accumulation of the injurious autonomous form. Together, our results highlight additional mechanistic details of CaMKII autonomous activation.

Leveraging National Data and Regional Innovations to Right-Size Tobacco Treatment Policy for Behavioral Health in a Midwestern State.

BACKGROUND: People with mental health (MH) and substance use disorders (SUD) have high rates of tobacco use and tobacco-related mortality. They want to stop smoking and studies have shown they can quit, but few behavioral health facilities provide tobacco treatment. The purpose of this paper is to describe how a midwestern statewide behavioral health collaboration used regional data to pinpoint strengths and weaknesses in tobacco treatment trends, identified policies in neighboring states that were associated with high rates of tobacco treatment, and worked with state leaders to implement these policies to enhance treatment. METHODS: We used publicly available data from 2 SAMHSA annual national surveys of MH/SUD facilities to describe tobacco treatment services and policies in behavioral health facilities in Kansas and 3 neighboring states (Missouri, Nebraska and Oklahoma). We interviewed neighboring state leaders to identify policies they had implemented to boost tobacco recovery services in behavioral health. We collaborated with our state behavioral health agency to encourage adoption of similar policies. RESULTS: Using 7 years of survey data (2014-2020), rates for screening, counseling, and medications for tobacco dependence were highest in Oklahoma and Missouri facilities. Oklahoma had the highest percentages of facilities reporting smoke-free campuses. In all states, rates of tobacco service provision and smoke-free campuses were lower among SUD facilities than in MH facilities. State leaders associated several policies with high performance, including (a) requiring programs contracting with the state to conduct screening, provide counseling, and adopt smoke-free campuses (Oklahoma and Missouri); (b) state-based collection of tobacco treatment service provision data (Oklahoma); (c) providing facilities with free NRT for clients (Oklahoma); (d) setting benchmarks for service provision (Oklahoma); (e) comprehensive Medicaid coverage of cessation medications (Missouri). Upon review of these findings, Kansas behavioral health officials adopted a 2-year process to implement similar policies and are integrating tobacco treatment requirements into the state Certified Community Behavioral Health Clinic program. CONCLUSIONS: Summarizing and sharing freely-available data across states laid the groundwork for cross-border networking and policy change. State and federal agencies should integrate these policies into contracts and block grants to reduce tobacco-related disparities among individuals with behavioral health conditions.

Melatonin decreases IRF-3 protein expression in the gastrocnemius muscle, reduces IL-1ß and LPS plasma concentrations, and improves the lipid profile in rats with apical periodontitis fed on a high-fat diet.

To evaluate the effects of melatonin (MEL) on the expression of toll-like receptor-4 (TLR4); myeloid differentiation primary response protein-88 (MyD88); TIR-domain-containing adapter-inducing interferon-ß (TRIF); IFN regulatory-factor-3 (IRF-3); nuclear factor kappa-B (NF-κB); plasma concentrations of interleukin-1ß (IL-1ß) and lipopolysaccharide (LPS); and lipid profile of rats with apical periodontitis (AP) fed on a high-fat diet (HFD). Eighty 60-day-old rats were divided into eight groups: control, AP, HFD, HFDAP, CNMEL, APMEL, HFDMEL and HFDAPMEL. HFD groups were fed on a HFD for 107 days. On day 7, experimental AP was induced in the AP groups, and after 70 days, MEL (5 mg/kg) was administered to the MEL groups for 30 days. Plasma concentrations of LPS and IL-1ß were analyzed using enzyme-linked immunosorbent assay, and the lipid profile was analyzed using biochemical tests. The expression of proteins involved in the TLR4 pathway (TLR4, MyD88, TRIF, IRF-3 and NF-κB) in the gastrocnemius muscle (GM) was evaluated using western blotting and qRT-PCR. Treatment with MEL decreased IRF-3 protein expression in GM and IL-1ß plasma concentration in the APMEL and HFDMEL groups. Reduction in LPS plasma concentration was reported only in the HFDMEL group. Additionally, a decrease in LDL and an increase in HDL were observed in the HFDMEL and HFDAPMEL groups. Treatment with MEL exhibited anti-inflammatory and anti-hyperlipidemic effects attributed to HFD and AP by reducing the plasma concentrations of IL-1ß and LPS in addition to reducing IRF-3 protein expression in the GM, which is associated with the production of inflammatory cytokines.

Anaerobic ATP synthesis pathways and inorganic phosphate transport and their possible roles in encystment in Acanthamoeba castellanii.

Acanthamoeba castellanii is the etiological agent of amoebic keratitis and is present in the environment in trophozoite or cyst forms. Both forms can infect the vertebrate host and colonize different tissues. The high resistance of cysts to standard drugs used in clinics contributes to the lack of effective treatments. Therefore, in this context, studies have emerged to understand cyst physiology and metabolism. Phosphate transporters are proteins responsible for the uptake of extracellular inorganic phosphate and transport to the cytosol. This work aims to verify the relationship between Pi transport and energetic metabolism in cysts of A. castellanii. The phosphate uptake ratio was higher in cysts compared with trophozoites. Recently, three sequences related to phosphate transporters have been identified in the A. castellanii genome (AcPHS1, AcPHS2, and AcPHS3); the messenger RNA expression levels of which differ depending on the amoeba life form. Pi uptake in cysts displayed peak activity at alkaline pH, whereas Pi transport in trophozoites was not affected in the same pH ranges. Cysts harbor a low-affinity Pi transport system (K0,5 and Vmax values of 1.76 ± 0.26 mM and 104.6 ± 6.3 nmol Pi × h-1 × 106 cells) compared to the trophozoite phosphate transport system. Pi transport seems important for anaerobic adenosine triphosphate synthesis in cysts, which initially occurs through the glycolytic pathway and subsequently through the pyruvate ferredoxin oxidoreductase pathway. Altogether, these results suggest that contrary to that previously postulated, cysts are active metabolic forms, and, as noted in trophozoites, phosphate uptake is important for energetic metabolism.

Vaping, Perceptions of Vaping, and Plans to Quit Among E-cigarette Users in the United States and the United Kingdom.

INTRODUCTION: Government and health organizations in the United States and the United Kingdom have taken different stances on e-cigarettes policy. To explore the potential effects of these policies, we describe e-cigarette user characteristics, intentions to quit, and perceived attitudes toward vaping. METHODS: We used the online crowdsourcing platform Prolific to conduct a cross-sectional survey of current vapers in both countries. Measures were drawn from international surveys. RESULTS: The sample included 1044 vapers (524 United Kingdom; 520 United States) with a mean age of 34. Samples differed by gender (United States: 57% male vs 45% in United Kingdom), race (United States: 79% White vs 90% in United Kingdom) and employment (United States: 73% employed vs 79% in United Kingdom). UK respondents were more likely than US respondents to be ever smokers (89% vs 71%, p < .0001); be daily vapers (69% vs 53%, p < .0001) and to use e-cigarettes to quit smoking (75% vs 65%, p < .0007). Most vapers in the United Kingdom and the United States want to stop vaping (62% vs 61%; p < .9493), but US respondents plan to quit significantly sooner (odds ratio 0.47, p < .0004). Attitudes differed as well. Over half (56%) of UK respondents reported their government-approved e-cigarette use, and 24% felt health care providers had positive views on e-cigarettes versus 29% and 13% from the United States, respectively (p < .0004 for both). CONCLUSIONS: Plans for quitting and perceptions regarding e-cigarettes differ markedly between demographically similar groups of vapers in the two countries. Future research should determine whether e-cigarette cessation for adults should be a public health goal, and if so, identify effective ways to stop. IMPLICATIONS: The contribution of this study is that it describes differences in behaviors and attitudes of vapers recruited through the same research platform and adjusted to account for minor demographic differences across country samples. For clinicians, these findings suggest that most vapers would welcome assistance in quitting. For researchers and policymakers, findings suggest that government policy regarding nicotine devices might influence behaviors and attitudes related to use and also that future research is needed to determine effective ways to quit.

Hydrogen Peroxide Generation as an Underlying Response to High Extracellular Inorganic Phosphate (Pi) in Breast Cancer Cells.

According to the growth rate hypothesis (GRH), tumour cells have high inorganic phosphate (Pi) demands due to accelerated proliferation. Compared to healthy individuals, cancer patients present with a nearly 2.5-fold higher Pi serum concentration. In this work, we show that an increasing concentration of Pi had the opposite effect on Pi-transporters only in MDA-MB-231 when compared to other breast cell lines: MCF-7 or MCF10-A (non-tumoural breast cell line). Here, we show for the first time that high extracellular Pi concentration mediates ROS production in TNBC (MDA-MB-231). After a short-time exposure (1 h), Pi hyperpolarizes the mitochondrial membrane, increases mitochondrial ROS generation, impairs oxygen (O2) consumption and increases PKC activity. However, after 24 h Pi-exposure, the source of H2O2 seems to shift from mitochondria to an NADPH oxidase enzyme (NOX), through activation of PKC by H2O2. Exogenous-added H2O2 modulated Pi-transporters the same way as extracellular high Pi, which could be reversed by the addition of the antioxidant N-acetylcysteine (NAC). NAC was also able to abolish Pi-induced Epithelial-mesenchymal transition (EMT), migration and adhesion of MDA-MB-231. We believe that Pi transporters support part of the energy required for the metastatic processes stimulated by Pi and trigger Pi-induced H2O2 production as a signalling response to promote cell migration and adhesion.

Acanthamoeba castellanii phosphate transporter (AcPHS) is important to maintain inorganic phosphate influx and is related to trophozoite metabolic processes.

Acanthamoeba castellanii is a free-living amoeba and the etiological agent of granulomatous amoebic encephalitis and amoebic keratitis. A. castellanii can be present as trophozoites or cysts. The trophozoite is the vegetative form of the cell and has great infective capacity compared to the cysts, which are the dormant form that protect the cell from environmental changes. Phosphate transporters are a group of proteins that are able to internalize inorganic phosphate from the extracellular to intracellular medium. Plasma membrane phosphate transporters are responsible for maintaining phosphate homeostasis, and in some organisms, regulating cellular growth. The aim of this work was to biochemically characterize the plasma membrane phosphate transporter in A. castellanii and its role in cellular growth and metabolism. To measure inorganic phosphate (Pi) uptake, trophozoites were grown in liquid PYG medium at 28 °C for 2 days. The phosphate uptake was measured by the rapid filtration of intact cells incubated with 0.5 µCi of 32Pi for 1 h. The Pi transport was linear as a function of time and exhibited Michaelis-Menten kinetics with a Km = 88.78 ± 6.86 µM Pi and Vmax = 547.5 ± 16.9 Pi × h-1 × 10-6 cells. A. castellanii presented linear phosphate uptake up to 1 h with a cell density ranging from 1 × 105 to 2 × 106 amoeba × ml-1. The Pi uptake was higher in the acidic pH range than in the alkaline range. The oxygen consumption of living trophozoites increased according to Pi addition to the extracellular medium. When the cells were treated with FCCP, no effect from Pi on the oxygen flow was observed. The addition of increasing Pi concentrations not only increased oxygen consumption but also increased the intracellular ATP pool. These phenomena were abolished when the cells were treated with FCCP or exposed to hypoxia. Together, these results reinforce the hypothesis that Pi is a key nutrient for Acanthamoeba castellanii metabolism.

Potency evaluation of rabies vaccine for human use: The impact of reducing the number of animals per dilution - Part 2.

The most critical parameter for the quality control of the rabies vaccine is potency, which is evaluated by challenge test in mice while using a large animal number. Because the 3Rs concept is applied worldwide, it becomes necessary to develop alternative methods to demonstrate the production consistency of these vaccines and reduce the number of animals used for performing assays. Hence, the present study evaluated the impacts of reducing the number of mice used in the NIH test for such vaccines. A retrospective data analysis compared vaccines tested in the standard test with the results of the reduced test using only the first cages of each dilution and considering the second cages as their replicates. The relevance of the reduced assay was evaluated using Bland- Altman plot and CCC. Reliability was assessed by CV% and confidence intervals, while the impact of the reduced mouse number was evaluated by the analysis of the confidence interval of potency results and regression, linearity and parallelism parameters. The results demonstrated the feasibility of reducing to eight mice per dilution in routine assays, with complete statistical validation of the resulting potency, allowing the number of animals used for the test vaccines to be reduced by 50%.

Influence of anti-allergic drugs used systemically on the process of root resorption during delayed tooth replantation: A study in rats.

BACKGROUND/AIM: Anti-allergic drugs can inhibit the hard tissue resorption process, and due to similarities between root resorption and bone mechanisms, it can be inferred that these drugs may also control root resorption. The aim of this study was to analyze the effects of anti-allergic drugs used systemically on the process of root resorption following delayed tooth replantation. MATERIALS AND METHODS: Thirty-two maxillary right incisors of rats were extracted and subsequently replanted. Rats were divided into four groups according to the anti-allergic drug administered: the rats in groups DEX, Q, and MO were treated systemically with dexamethasone phosphate, quercetin, and montelukast, respectively, and no systemic medication was administered to rats in group C. After 60 days, the animals were euthanized, and the specimens were processed for histomorphometric and immunohistochemical analyses. Statistical significance was set at P < .05. RESULTS: There were no significant differences between the groups in terms of inflammatory resorption, replacement resorption, or presence of tartrate-resistant acid phosphatase. In terms of events occurring in the periodontal ligament space, there was a difference between groups Q and MO due to the presence of dental ankylosis and inflammatory connective tissue (P < .05). A difference in inflammatory cells was also observed through CD45 immunolabeling between the DEX and Q groups when compared to the C group (P < .05). CONCLUSION: The systemic administration of anti-allergic drugs did not have an effect on the process of root resorption following delayed tooth replantation.

Tartrate-resistant phosphatase type 5 in Trypanosoma cruzi is important for resistance to oxidative stress promoted by hydrogen peroxide.

Trypanosoma cruzi (the causative agent of Chagas disease) presents a complex life cycle that involves adaptations in vertebrate and invertebrate hosts. As a protozoan parasite of hematophagous insects and mammalian hosts, T. cruzi is exposed to reactive oxygen species (ROS). To investigate the functionality of T. cruzi tartrate-resistant acid phosphatase type 5 (TcACP5), we cloned, superexpressed and purified the enzyme. Purified TcACP5 exhibited a Vmax and apparent Km for pNPP hydrolysis of 7.7 ±â€¯0.2 nmol pNP × µg-1 × h-1 and 169.3 ±â€¯22.6 µM, respectively. The pH dependence was characterized by sharp maximal activity at pH 5.0, and inhibition assays demonstrated its sensitivity to acid phosphatase inhibitors. Similar activities were obtained with saturating concentrations of P-Ser and P-Thr as substrates. The enzyme metabolizes hydrogen peroxide (H2O2) in vitro, and parasites superexpressing this enzyme were more resistant to oxidative stress promoted by H2O2. Taken together, these results suggest that TcACP5 plays a central role in phosphoryl transfer and redox reactions.

Climatically-mediated landcover change: impacts on Brazilian territory.

In the face of climate change threats, governments are drawing attention to policies for mitigating its effects on biodiversity. However, the lack of distribution data makes predictions at species level a difficult task, mainly in regions of higher biodiversity. To overcome this problem, we use native landcover as a surrogate biodiversity, because it can represent specialized habitat for species, and investigate the effects of future climate change on Brazilian biomes. We characterize the climatic niches of native landcover and use ecological niche modeling to predict the potential distribution under current and future climate scenarios. Our results highlight expansion of the distribution of open vegetation and the contraction of closed forests. Drier Brazilian biomes, like Caatinga and Cerrado, are predicted to expand their distributions, being the most resistant to climate change impacts. However, these would also be affected by losses of their closed forest enclaves and their habitat-specific or endemic species. Replacement by open vegetation and overall reductions are a considerable risk for closed forest, threatening Amazon and Atlantic forest biomes. Here, we evidence the impacts of climate change on Brazilian biomes, and draw attention to the necessity for management and attenuation plans to guarantee the future of Brazilian biodiversity.

Does Pain in the Neonatal Period Influence Motor and Sensory Functions in a Similar Way for Males and Females During Post-Natal Development in Rats?

OBJECTIVE : Early pain experiences can lead to disruption in the long-term responses to pain and in abnormal development and behavior in rodents. We evaluated the sensory and motor development of Wistar rats after exposure to painful stimulation (repetitive needle prickling) immediately after birth. METHODS : Male and female rats were followed up to 6 months of life, and sensory and motor functions were investigated by testing paw withdrawal with von Frey filaments, calibrated forceps (CF), and grip strength (GS) tests. RESULTS : Body weight increased with age and tended to be smaller in pain groups compared with their controls of the same sex. GS values also increased with age in controls but were stable and even decreased in pain groups from 120 up to 180 days. The von Frey filaments test showed higher values on the nonstimulated paws in male and female pain groups, with no differences between sides on the controls. The CF test showed smaller values on the stimulated paws in the pain group, with no differences between sides on the controls. CONCLUSIONS : Pain in the neonatal period influences sensory and motor functions negatively during development in male and female rats, even long term after the painful stimulus is ceased. The neonatal injury-induced hypersensitivity is persistent, and male and female rats respond similarly to the stimulus.

Rhodnius prolixus: modulation of antioxidant defenses by Trypanosoma rangeli.

Trypanosoma rangeli is a protozoan parasite of insects and mammals that is challenged by the constant action of reactive oxygen species, generated either by its own metabolism or through the host immune response. The aim of this work was to investigate whether T. rangeli is able to modify the redox state of its insect vector, Rhodnius prolixus, through the modulation of such antioxidant enzymes as superoxide dismutase (SOD), catalase, and GPx present in the midgut of the insect. We verified that in R. prolixus fed with blood infected with T. rangeli there is an increase in SOD activity in the anterior and posterior midguts. However, the activities of enzymes related to hydrogen peroxide and hydroperoxides metabolism, such as catalase and GPx, were decreased in relation to the insect control group, which was only fed blood. These changes in the redox state of the vector led to an increase in lipid peroxidation and thiol oxidation levels in the anterior and posterior midgut tissues. We also verified that the addition of 1 mM GSH in the blood meal of the infected insects increased the proliferation of these parasites by 50%. These results suggest that there is an increase in oxidative stress in the insect gut during T. rangeli infection, and this condition could contribute to the control of the proliferation of these parasites.

Peanut (Arachis hypogaea L.) seeds and by-products in metabolic syndrome and cardiovascular disorders: A systematic review of clinical studies.

BACKGROUND: Cardiovascular disease (CVDs) is the leading cause of death worldwide. The main risk factors are hypertension, diabetes, obesity, and increased serum lipids. The peanut (Arachis hypogaea L.), also known as the groundnut, goober, pindar, or monkey nut, belongs to the Fabaceae family and is the fourth most cultivated oilseed in the world. The seeds and skin of peanuts possess a rich phytochemical profile composed of antioxidants, such as phenolic acids, stilbenes, flavonoids, and phytosterols. Peanut consumption can provide numerous health benefits, such as anti-obesity, antidiabetic, antihypertensive, and hypolipidemic effects. Accordingly, peanuts have the potential to treat CVD and counteract its risk factors. PURPOSE: This study aims to critically evaluate the effects of peanuts on metabolic syndrome (MetS) and CVD risk factors based on clinical studies. METHOD: This review includes studies indexed in MEDLINE-PubMed, COCHRANE, and EMBASE, and the Preferred Reporting Items for a Systematic Review and Meta-Analysis guidelines were adhered to. RESULTS: Nineteen studies were included and indicated that the consumption of raw peanuts or differing forms of processed foods containing peanut products and phytochemicals could improve metabolic parameters, such as glycemia, insulinemia, glycated hemoglobin, lipids, body mass index, waist circumference, atherogenic indices, and endothelial function. CONCLUSION: We propose that this legume and its products be used as a sustainable and low-cost alternative for the prevention and treatment of MetS and CVD. However, further research with larger sample sizes, longer intervention durations, and more diverse populations is needed to understand the full benefit of peanut consumption in MetS and CVD.

Investigating the Neuroprotective and Cognitive-Enhancing Effects of Bacopa monnieri: A Systematic Review Focused on Inflammation, Oxidative Stress, Mitochondrial Dysfunction, and Apoptosis.

The aging of the global population has increased the prevalence of neurodegenerative conditions. Bacopa monnieri (BM), an herb with active compounds, such as bacosides A and B, betulinic acid, loliolide, asiatic acid, and quercetin, demonstrates the potential for brain health. Limited research has been conducted on the therapeutic applications of BM in neurodegenerative conditions. This systematic review aims to project BM's beneficial role in brain disorders. BM has anti-apoptotic and antioxidant actions and can repair damaged neurons, stimulate kinase activity, restore synaptic function, improve nerve transmission, and increase neuroprotection. The included twenty-two clinical trials demonstrated that BM can reduce Nuclear Factor-κB phosphorylation, improve emotional function, cognitive functions, anhedonia, hyperactivity, sleep routine, depression, attention deficit, learning problems, memory retention, impulsivity, and psychiatric problems. Moreover, BM can reduce the levels of pro-inflammatory biomarkers and oxidative stress. Here, we highlight that BM provides notable therapeutic benefits and can serve as a complementary approach for the care of patients with neurodegenerative conditions associated with brain disorders. This review adds to the growing interest in natural products and their potential therapeutic applications by improving our understanding of the mechanisms underlying cognitive function and neurodegeneration and informing the development of new therapeutic strategies for neurodegenerative diseases.

Influence of photoactivation on tissue response to different dyes used in photodynamic therapy and laser ablation therapy.

Laser ablation therapy (LA) uses Indocyanine Green dye (ICG) which efficiently absorbs laser energy and the increased temperature results in an instantaneous flame that chars tissue and microbes. Photodynamic therapy (PDT) uses different dyes that are activated by light to kill bacteria. This study evaluated the biocompatibility of the dye Curcumin (CUR), Methylene Blue (MB), and Indocyanine Green (ICG) before and after laser activation (ACT). Polyethylene tubes containing one of the dyes were implanted in the subcutaneous tissue of 32 rats (4 tubes per rat) which were divided into 8 groups: C - control (saline solution); C + ACT (Red Laser 660 nm); CUR; CUR + ACT (480 nm blue LED); MB; MB + ACT (Red Laser 660 nm); ICG; ICG + ACT (810 nm Infrared Laser). After 7 and 30 days (n = 8/time), the rats were euthanized and the tubes with the surrounding tissue were removed and processed for histological analysis of inflammation using H&E stain, and collagen fiber maturation using picrosirius red (PSR). A two-way analysis of variance statistical test was applied (p < 0.05). At 7 days, regardless of laser activation, the CUR group showed a greater inflammatory infiltrate compared to the ICG and control groups, and the MB group had a greater inflammation only in relation to the control (p < 0.05). At 30 days, CUR and MB groups showed a greater inflammatory infiltrate than the control (p < 0.05). ICG group was equal to the control in both periods, regardless of the laser activation (p > 0.05). Laser activation induced the proliferation of collagen immature fibers at 7 days, regardless of the dye (p < 0.05). The CUR group showed a lower percentage of immature and mature fibers at 7 days, compared to ICG and control (p < 0.05) and, at 30 days, compared to control (p < 0.05). Regardless of laser activation, the ICG showed the results of collagen maturation closest to the control (p > 0.05). It was concluded that all dyes are biocompatible and that laser activation did not interfere with biocompatibility. In addition, the maturity of collagen was adequate before and after the laser activation. These results demonstrate that the clinical use of dyes is safe even when activated with a laser.

Inhibition of ecto-phosphatase activity in conidia reduces adhesion and virulence of Metarhizium anisopliae on the host insect Dysdercus peruvianus.

Metarhizium anisopliae is an entomopathogenic fungus with the ability to infect a broad range of arthropods, and have evolved distinct strategies for their attachment to hosts. Here, we describe the characterisation of ecto-phosphatase activity on the conidia surface of M. anisopliae and its relevance in the host interaction process. Ecto-phosphatase activity was linear for 60 min and during this time, was linear with the increase of cell density. The optimum pH was in the acidic range and some divalent metals, such as Cu(2+), Cd(2+) and Zn(2+), inhibited ecto-phosphatase activity. The activity was also reduced by phosphatase inhibitors. Importantly, the inhibition of phosphatase activity in conidia reduced the adhesion to Dysdercus peruvianus (Hemiptera: Pyrrhocoridae) integument and, consequently and indirectly, M. anisopliae infection. The results herein presented show, for the first time, the importance of ecto-phosphatase activity in M. anisopliae conidia and provide the first evidence of its direct involvement in adhesion and host infection.

NADPH oxidase biology and the regulation of tyrosine kinase receptor signaling and cancer drug cytotoxicity.

The outdated idea that reactive oxygen species (ROS) are only dangerous products of cellular metabolism, causing toxic and mutagenic effects on cellular components, is being replaced by the view that ROS have several important functions in cell signaling. In aerobic organisms, ROS can be generated from different sources, including the mitochondrial electron transport chain, xanthine oxidase, myeloperoxidase, and lipoxygenase, but the only enzyme family that produces ROS as its main product is the NADPH oxidase family (NOX enzymes). These transfer electrons from NADPH (converting it to NADP-) to oxygen to make O(2)•-. Due to their stability, the products of NADPH oxidase, hydrogen peroxide, and superoxide are considered the most favorable ROS to act as signaling molecules. Transcription factors that regulate gene expression involved in carcinogenesis are modulated by NADPH oxidase, and it has emerged as a promising target for cancer therapies. The present review discusses the mechanisms by which NADPH oxidase regulates signal transduction pathways in view of tyrosine kinase receptors, which are pivotal to regulating the hallmarks of cancer, and how ROS mediate the cytotoxicity of several cancer drugs employed in clinical practice.

Bleaching gel volume influences hydrogen peroxide diffusion, inflammation, and the presence of nitric oxide in the pulp tissue: in vitro and in vivo model.

OBJECTIVE: To assess whether bleaching gel volume influences chromatic changes, hydrogen peroxide (HP) diffusion, inflammation, and oxidative stress in the pulp tissue. METHODOLOGY: A total of 60 bovine teeth were divided into four groups, according to bleaching gel volume (n=15): without gel (WG); V30 (30 µL of 35% HP); V60 (60 µL); and V120 (120 µL). HP diffusion analysis was performed in the first session (T1). Chromatic changes (ΔE, ΔE00, and WID) were assessed after the first (T1), second (T2), third (T3) sessions, and 15 d (T4) after the end of treatment. Moreover, 20 rats were randomly divided into four groups (n=10) and their upper first molars were treated with different gel volumes: control (no treatment); V2 (2 µL of 17.5% HP); V4 (4 µL); and V8 (8 µL). After 24 h, rats were euthanized and the specimens processed for histological and immunohistochemical (nitric oxide synthase) evaluation. Data were analyzed using the Wilcoxon and Mann-Whitney tests (p<0.05). RESULTS: In vitro (bovine teeth), chromatic changes were not influenced by bleaching gel volume, showing similar values in all groups and sessions, except for the control group (p<0.05). The V120 group had the highest HP diffusion values (p<0.05). In vivo (pulp tissue), the V4 and V8 groups showed the highest inflammatory infiltrate in the pulp and significant oxidative stress (p<0.05). CONCLUSION: The adverse effects on the dental pulp related to HP diffusion, pulp inflammation, and oxidative stress depend on bleaching gel volume, while the bleaching effect is not proportional to the volume used.