142 research outputs found

    Phenolic compounds and carotenoids amounts on guava epicarp injury, 'girdling'

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    A anomalia do epicarpo da goiaba, comumente relatada por agricultores e técnicos como o "anelamento juvenil da goiaba", tem causado preocupação devido à desinformação sobre o assunto. O objetivo deste estudo foi analisar quimicamente as concentrações de substâncias fenólicas e carotenoides na região do epicarpo de goiabas afetadas pelo "anelamento", visando a caracterizar essa anomalia previamente relatada. Foram analisadas substâncias fenólicas (taninos, flavonas/flavonóis, antocianinas e fenóis totais) e carotenoides em epicarpos de frutos verdes e maduros de goiabeiras cv. Paluma, com e sem anomalia. O delineamento experimental adotado foi o inteiramente casualizado, sendo estabelecidos seis tratamentos com o epicarpo dos frutos maduro sem anomalia na região inferior (FMSI); frutos maduros sem injuria na região superior (FMSS); frutos verdes sem anomalia na região inferior (FVSI); frutos verdes sem anomalia na região superior (FVSS); frutos verdes com anomalia na região inferior (FVCI); frutos verdes com anomalia na região superior (FVCS). Dentre as substâncias analisadas, os carotenoides, os taninos e os fenóis totais mostram indicativos para a caracterização do anelamento. Tanto substâncias fenólicas quanto carotenoides apresentam propriedades antioxidantes e, dessa forma, poderiam estar relacionadas à defesa antioxidante causada por um fator de estresse ainda desconhecido, que promove o "anelamento" característico apresentado pelas goiabas.Guava epicarp injuries, popularly known as "girdling", have been concerned technicians and producers due to misunderstand about their causes. The objective of this study was to analyze the amounts of phenolic compounds and carotenoids present on guava epicarp region affected by injury ("girdling") in order to characterize chemically those regions. Concentrations of phenolic compounds (tannins, flavones/flavonols, anthocyanins and total phenolic compounds) and carotenoids were analyzed on tissue from unripe and ripe guava injured and non-injured epicarp fruits (Psidium guajava cv. Paluma). The experimental design was randomized, and were established six treatments: epicarp from ripe fruit without injury in the lower (FMSI) and upper region (FMSS) of the fruit, unriped fruit without injury (lower - FVSI - and upper region - FVSS), injured unriped fruit with injury (lower - FVCI - and upper region - FVCS). Higher concentrations of phenolic compounds, carotenoids of tannins, were found on tissues of unripe fruit epicarp with "girdling" when compared with health epicarps. Results showed the participation of phenolics compounds (tannins) and carotenoids as possible substances that characterized the injury formation. Although phenolic compounds and carotenoids have antioxidant properties and are often related as antioxidant defenses, the causes of "girdling" of guava fruits are still unknown

    EVALUATION OF TORQUE MOMENT IN ESTHETIC BRACKETS

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    Objectives: To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires. Materials and Methods: This study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5–40° were examined. Results: The torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires. Conclusions: The current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires

    Correlation of Heat Shock Protein Expression to Gender Difference in Development of Stress-Induced Gastric Mucosal Injury in Rats

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    Recent studies have indicated that heat shock proteins (HSPs), which function as molecular chaperones, play important roles in cellular responses to stress-related events. However, the gender difference in the expression of HSP in the gastric mucosa remains unclear. In order to understand the mechanism of gender difference in the prevalence or severity of gastric mucosal lesions, the expression level of HSP and the correlation of estrogen to HSP induction in the gastric mucosa were evaluated in this study. The basal expression levels of HSP60 and HSP90 in the gastric mucosa were significantly higher in females than those in males. The gastric ulcer index was significantly higher in male rats compared to female rats observed after 12 h water immersion stress exposure. At this time point, the expression levels of HSP60 and HSP90 in the gastric mucosa were significantly higher in females than those in males. An estrogen-treatment significantly induced the expression of HSP60, HSP70 and HSP90 in the gastric mucosa. Inversely, an ovariectomy dramatically reduced the expression of HSP60, HSP70 and HSP90 in the gastric mucosa. Our results suggested that estrogen might play an important role in gastric mucosal protection with the induction of gastric mucosal HSPs

    Development of Stage 4 Macular Hole after Spontaneous Closure in a Patient with Stage 2 Macular Hole and a Lamellar Macular Hole-Associated Epiretinal Proliferation

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    Herein, we report the longitudinal observation of a case with reopening of the macular hole associated with a lamellar macular hole-associated epiretinal proliferation (LHEP) followed by spontaneous closure in patients with stage 2 idiopathic macular hole. A 64-year-old woman was referred for the decreased visual acuity (VA) and acute anorthopia in the right eye. Funduscopy and optical coherence tomography (OCT) showed stage 2 full-thickness macular hole without posterior vitreous detachment (PVD) and operculum formation. Her best-corrected visual acuity (BCVA) was 20/32. One month later, the diameter of the macular hole was getting small and VA improved. Six months later, the macular hole was treated spontaneously with the attached hyaloid membrane to the macula by OCT and the BCVA improved to 20/20. Fourteen months after the first visit, the BCVA decreased to 20/50 and the patient was diagnosed with stage 4 macular hole with complete PVD. OCT showed full-thickness macular hole with a LHEP in the right eye. After 25G-gauge vitrectomy with the peeling of internal limiting membrane (ILM) and LHEP, the macular hole was closed and BCVA finally improved to 20/25. Spontaneous macular hole closure without PVD may rarely occur in patients with LHEP. The surgical removal of ILM and LHEP may contribute to the successful macular hole closure after vitrectomy

    Magnetization and transport properties in the superconducting Pr2_{2}Ba4_{4}Cu7_{7}O15−δ_{15-\delta} with metallic double-chain

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    We have reported the effect of pressure on the magnetization, and transport properties in the nominal composition Pr2_{2}Ba4_{4}Cu7_{7}O15−δ_{15-\delta} synthesized by a sol-gel technique. A reduction treatment of the as-sintered sample in vacuum causes higher superconductivity achieving Tc,on=∼30T_{c,on}=\sim 30 K for δ=0.94\delta =0.94. Application of hydrostatic pressure on the oxygen depleted sample enhances its onset temperature up to 36 K at 1.2 GPa, indicating the nearly optimum doping level of the charge carrier in comparison to the pressure dependence of lower TcT_{c} samples with δ=0.45\delta =0.45. Seebeck coefficient of the superconducting sample shows a metallic conduction, followed by a clear drop below Tc,onT_{c,on} and is in its temperature dependence below 100 K quite different from that of the non-superconducting one. This finding strongly suggests a dramatic change of the electronic state along the CuO double chain due to the reduction treatment for the appearance of superconductivity .Comment: 5 pages,4 figure
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