Nanocomposite PAAm/methyl cellulose/montmorillonite hydrogel: Evidence of synergistic effects for the slow release of fertilizers

In this work, we synthesized a novel series of hydrogels composed of polyacrylamide (PAAm), methylcellulose (MC), and calcic montmorillonite (MMt) appropriate for the controlled release of fertilizers, where the components presented a synergistic effect, giving very high fertilizer loading in their structure. The synthesized hydrogel was characterized in relation to morphological, hydrophilic, spectroscopic, structural, thermal, and kinetic properties. After those characterizations, the application potential was verified through sorption and desorption studies of a nitrogenated fertilizer, urea (CO(NH2)2). The swelling degree results showed that the clay loading considerably reduces the water absorption capability; however, the hydrolysis process favored the urea adsorption in the hydrogel nanocomposites, increasing the load content according to the increase of the clay mass. The FTIR spectra indicated that there was incorporation of the clay with the polymeric matrix of the hydrogel and that incorporation increased the water absorption speed (indicated by the kinetic constant k). By an X-ray diffraction technique, good nanodispersion (intercalation) and exfoliation of the clay platelets in the hydrogel matrix were observed. Furthermore, the presence of the montmorillonite in the hydrogel caused the system to liberate the nutrient in a more controlled manner than that with the neat hydrogel in different pH ranges. In conclusion, excellent results were obtained for the controlled desorption of urea, highlighting the hydrolyzed hydrogels containing 50% calcic montmorillonite. This system presented the best desorption results, releasing larger amounts of nutrient and almost 200 times slower than pure urea, i.e., without hydrogel. The total values of nutrients present in the system show that this material is potentially viable for application in agriculture as a nutrient carrier vehicle. © 2013 American Chemical Society.

Organically produced coffee exerts protective effects against the micronuclei induction by mutagens in mouse gut and bone marrow

While researchers have extensively evaluated the beneficial effects of coffee consumption in reducing the frequency of certain diseases, studies examining the differences between organic and conventional coffee intake are still needed. Therefore, this paper aims to investigate the functional effects of organic and conventional coffee by examining both its chemical composition and its mutagenic/antimutagenic properties. Infusions of 10% or 20% (w/v) of organic and conventional coffee were administered by gavage (10 mL/kg b.w., once or twice a day) to male Swiss mice against doxorubicin (DXR) and 1,2-dimethylhydrazine dihydrochloride (DMH)-induced mutagenicity. The levels of chlorogenic acids, caffeine and trigonelline from the coffee infusions and oxidative stress analysis from the liver were measured by HPLC. Gut and bone marrow micronucleus assays were used as mutagenic/antimutagenic endpoints, as well as the crypt measurements and gut apoptosis index. The in vivo tests revealed that only organic coffee exerted protective effects, despite oxidative stress analysis and crypt measurements not showing differences among treatments. Intriguingly, the low dose (10% w/v mL/kg) displayed a robust protective effect that showed a significant reduction in bone marrow micronuclei (26.8%), gut micronuclei (11.5%) and apoptosis (27.8%), whereas the higher coffee dose (2 × 20% w/v) only showed a protective effect against bone marrow micronucleus (43.7%). These results highlight that organic coffee could be considered to have beneficial functional effects, although it is still a challenge to define conclusions from analytical data and all the possible interactions from this complex food matrix. © 2013 Elsevier Ltd. All rights reserved.

Platelet-Rich Plasma And Chronic Wounds: Remaining Fibronectin May Influence Matrix Remodeling And Regeneration Success

Background: Platelet-rich plasma has been largely used as a therapeutic option for the treatment of chronic wounds of different etiologies. The enhanced regeneration observed after the use of platelet-rich plasma has been systematically attributed to the growth factors that are present inside platelets' granules. Aim: We hypothesize that the remaining plasma and platelet-bound fibronectin may act as a further bioactive protein in platelet-rich plasma preparations. Methods: Recent reports were analyzed and presented as direct evidences of this hypotheses. Results: Fibronectin may directly influence the extracellular matrix remodeling during wound repair. This effect is probably through matrix metalloproteinase expression, thus exerting an extra effect on chronic wound regeneration. Conclusions: Physicians should be well aware of the possible fibronectin-induced effects in their future endeavors with PRP in chronic wound treatment. © 2013 International Society for Cellular Therapy.

Side Effects of Neem Oil on the Midgut Endocrine Cells of the Green Lacewing Ceraeochrysa claveri (Navas) (Neuroptera: Chrysopidae)

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

Environmental effects on viscoelastic behavior of carbon fiber/PEKK thermoplastic composites

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effects of maternal diabetes on male offspring: high cell proliferation and increased activity of MMP-2 in the ventral prostate

This study presents a comprehensive view of the histological and functional status of the prostate of adult rat offspring of mothers subjected to gestational diabetes induced by alloxan. The ventral prostate of male adult offspring of diabetic (DP) or normal (CP) mothers was evaluated for collagen fibres, cell death, fibroblasts, smooth muscle cells, cell proliferation, matrix metalloproteinases (MMPs), androgen receptors (AR), transforming growth factor beta 1 (TGF beta-1), catalase and total antioxidant activity. The prostates of DP animals were lower in weight than those of the CP group. The DP group also exhibited hyperglycaemia and hypotestosteronemia, higher cell proliferation and AR expression, a reduction in alpha-actin (possibly interfering with the reproductive function of the prostate), and enhanced activity of MMP-2, although the absolute content of MMP-2 was lower in this group. These findings were associated with increased TGF beta-1 and decreased collagen distribution. The prostates of DP rats additionally exhibited reductions in catalase and total antioxidant activity. Thus, rats developing in a diabetic intrauterine environment have glycaemic and hormonal changes that impact on the structure and physiology of the prostate in adulthood. The increased AR expression possibly leads to elevated cell proliferation. Stromal remodelling was characterized by enhanced activity of MMP-2 and collagen degradation, even with increased TGF beta-1 activation. These changes associated with increased oxidative stress might interfere with tissue architecture and glandular homeostasis.

Phototherapy up-regulates dentin matrix proteins expression and synthesis by stem cells from human-exfoliated deciduous teeth

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

Leptin Effects on the Regenerative Capacity of Human Periodontal Cells

Obesity is increasing throughout the globe and characterized by excess adipose tissue, which represents a complex endocrine organ. Adipose tissue secrets bioactivemolecules called adipokines, which act at endocrine, paracrine, and autocrine levels. Obesity has recently been shown to be associated with periodontitis, a disease characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium, and also with compromised periodontal healing. Although the underlying mechanisms for these associations are not clear yet, increased levels of proinflammatory adipokines, such as leptin, as found in obese individuals, might be a critical pathomechanistic link. The objective of this study was to examine the impact of leptin on the regenerative capacity of human periodontal ligament (PDL) cells and also to study the local leptin production by these cells. Leptin caused a significant downregulation of growth (TGF beta 1, and VEGFA) and transcription (RUNX2) factors as well as matrix molecules (collagen, and periostin) and inhibited SMAD signaling under regenerative conditions. Moreover, the local expression of leptin and its full-length receptor was significantly downregulated by inflammatory, microbial, and biomechanical signals. This study demonstrates that the hormone leptin negatively interferes with the regenerative capacity of PDL cells, suggesting leptin as a pathomechanistic link between obesity and compromised periodontal healing.

Beneficial Effects of Adiponectin on Periodontal Ligament Cells under Normal and Regenerative Conditions

Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic link. The aim of this in vitro study was to examine the effects of adiponectin on periodontal ligament (PDL) cells under normal and regenerative conditions, and to study the regulation of adiponectin and its receptors in these cells. Adiponectin stimulated significantly the expression of growth factors and extracellular matrix, proliferation, and in vitro wound healing, reduced significantly the constitutive tumor necrosis factor-alpha expression, and caused a significant upregulation of its own expression. The beneficial actions of enamel matrix derivative on a number of PDL cell functions critical for periodontal regeneration were partially enhanced by adiponectin. The periodontopathogen Porphyromonas gingivalis inhibited the adiponectin expression and stimulated the expression of its receptors. In conclusion, reduced levels of adiponectin, as found in type 2 diabetes and obesity, may compromise periodontal health and healing.

Effects of immersion media and repolishing on color stability and superficial morphology of nanofilled composite resin

This study evaluated the influence of fluoride mouth rinses and repolishing on the superficial morphology and color stability of nanofilled resin. About 150 specimens were prepared and polished using aluminum oxide discs for 15 s with a pressure of 2 kg. The experimental groups were divided according to the immersion medium (artificial saliva, 0.5% sodium fluoride, Fluordent Reach, Oral B, Fluorgard) and repolishing procedure (without and with). The specimens were continuously immersed for 1 week. Thereafter, half of each sample was repolished. A color reading was performed after 24 h of immersion in the artificial saliva baseline, after continuous immersion, and after repolishing. The superficial morphology was examined using scanning electron microscopy (SEM) in a qualitative way. Color change (∆E) data were submitted to a mixed analysis of variance using a Shapiro-Wilk test (p>0.05 for the different immersion media) and Sidak's test (p<0.05 for the differences between groups). In the interaction between the repolishing and the immersion media, Fluorgard showed a statistical difference between the ∆E values with and without repolishing (p<0.0001). On the SEM observations, both Fluordent Reach and Fluorgard caused degradation of the superficial resinous matrix of the composite after continuous immersion. This matrix was removed after repolishing.

Effects of electroacupuncture on experimental periodontitis in rats

Background: Acupuncture has shown the capability of modulating the immuno-inflammatory response of the host. This study aims to evaluate the effects of electroacupuncture (EA) on ligature-induced periodontitis in rats. Methods: Thirty-two animals were divided into four groups: 1) control; 2) experimental periodontitis (EP); 3) sham-treated (EP/EA-sham); and 4) treated with EA (EP/EA). For the EP groups, a ligature was placed around the right mandibular first molars at day 1. Sessions of EA or EA-sham were assigned every other day. For EA treatment, large intestine meridian points LI4 and LI11 and stomach meridian points ST36 and ST44 were used. EA-sham was performed in off-meridian points. Animals were euthanized at day 11. Histomorphometric and microtomographic analyses were performed. Immunolabeling patterns for the receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), and tartrate-resistant acid phosphatase (TRAP) were assessed. Expressions of interleukin (IL)-1 beta, matrix metalloproteinase (MMP)-8, IL-6, and cyclooxygenase (COX)-2 messenger RNAs (mRNAs) were evaluated by quantitative reverse transcription-polymerase chain reaction. Data were analyzed statistically (P < 0.05, analysis of variance). Results: Histomorphometric and microtomographic analyses demonstrated that group EP/EA presented reduced alveolar bone loss when compared to group EP (P < 0.05). Reduced RANKL immunolabeling and fewer TRAP-positive multinucleated cells were observed in the EA-treated group in relation to group EP. No differences were observed in OPG expression among groups. EA treatment decreased the genic expression of IL-1 beta and MMP-8 (P < 0.05), increased the mRNA expression of IL-6 (P < 0.05), and did not modify the genic expression of COX-2 in animals with EP (P > 0.05). Conclusion: It can be concluded that EA reduced periodontal tissue breakdown and the expression of some proinflammatory mediators and a proresorptive factor in EP in rats.

Morphological effects of neem (Azadirachta indica A. Juss) seed oil with known azadirachtin concentrations on the oocytes of semi-engorged Rhipicephalus sanguineus ticks (Acari: Ixodidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Patch size, functional isolation, visibility and matrix permeability influences neotropical primate occurrence within highly fragmented landscapes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Cissus quadrangularis Linn exerts dose-dependent biphasic effects: osteogenic and anti-proliferative, through modulating ROS, cell cycle and Runx2 gene expression in primary rat osteoblasts

Objectives: This report highlights phytoconstituents present in Cissus quadrangularis (CQ) extract and examines biphasic (proliferative and anti-proliferative) effects of its extract on bone cell proliferation, differentiation, mineralization, ROS generation, cell cycle progression and Runx2 gene expression in primary rat osteoblasts. Materials and methods: Phytoconstituents were identified using gas chromatography-mass spectroscopy (GC-MS). Osteoblasts were exposed to different concentrations (10-100g/ml) of CQ extract and cell proliferation and cell differentiation were investigated at different periods of time. Subsequently, intracellular ROS intensity, apoptosis and matrix mineralization of osteoblasts were evaluated. We performed flow cytometry for DNA content and real-time PCR for Runx2 gene expression analysis.Results: CQ extract's approximately 40 bioactive compounds of fatty acids, hydrocarbons, vitamins and steroidal derivatives were identified. Osteoblasts exposed to varying concentrations of extract exhibited biphasic variation in cell proliferation and differentiation as a function of dose and time. Moreover, lower concentrations (10-50g/ml) of extract slightly reduced ROS intensity, although they enhanced matrix mineralization, DNA content in S phase of the cell cycle, and levels of Runx2 expression. However, higher concentrations (75-100g/ml) considerably induced the ROS intensity and nuclear condensation in osteoblasts, while it reduced mineralization level, proportion of cells in S phase and Runx2 level of the osteogenic gene.Conclusions: These findings suggest that CQ extract revealed concentration-dependent biphasic effects, which would contribute notably to future assessment of pre-clinical efficacy and safety studies.

The Anti-Inflammatory Effects of the Methanolic Extract and Fractions from Davilla elliptica St. Hil. (Dilleniaceae) on Bothrops jararaca Envenomation

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