In Vitro Antibacterial Activity of Prenylated Guanidine Alkaloids from Pterogyne nitens and Synthetic Analogues

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

Immunoreactivity of synthetic peptides derived from proteins of Cryptococcus gattii

Aim: To determine the immunoreactivity of synthetic Cryptococcus-derived peptides. Materials & methods: A total of 63 B-cell epitopes from previously identified Cryptococcus gattii immunoreactive proteins were synthesized and evaluated as antigens in ELISAs. The peptides were first evaluated for their ability to react against sera from immunocompetent subjects carrying cryptococcal meningitis. Peptides that yielded high sensitivity and specificity in the first test were then retested with sera from individuals with other fungal pathologies for cross-reactivity determination. Results: Six of 63 synthetic peptides were recognized by antibodies in immunoassays, with a specificity of 100%, sensitivity of 78% and low cross-reactivity. Conclusion: We successfully determined the immunoreactivity of selected synthetic peptides of C. gattii derived proteins.

Micro-extração em fase sólida (SPME) in situ e comparação de compostos voláteis em variedades de manga (Mangifera indica L.) resistentes e suscetíveis à mosca-das-frutas Anastrepha obliqua (Macquart) (Diptera: Tephritidae)

Pós-graduação em Química - IQ

Histopathologycal findings in the ovaries and uterus of albino female rats promoted by co-administration of synthetic steroids and nicotine

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

The steady-state behavior of the synthetic and side-sensitive synthetic double sampling (X)over-bar charts

The steady-state average run length is used to measure the performance of the recently proposed synthetic double sampling (X) over bar chart (synthetic DS chart). The overall performance of the DS X chart in signaling process mean shifts of different magnitudes does not improve when it is integrated with the conforming run length chart, except when the integrated charts are designed to offer very high protection against false alarms, and the use of large samples is prohibitive. The synthetic chart signals when a second point falls beyond the control limits, no matter whether one of them falls above the centerline and the other falls below it; with the side-sensitive feature, the synthetic chart does not signal when they fall on opposite sides of the centerline. We also investigated the steady-state average run length of the side-sensitive synthetic DS X chart. With the side-sensitive feature, the overall performance of the synthetic DS X chart improves, but not enough to outperform the non-synthetic DS X chart. Copyright (C) 2014 John Wiley &Sons, Ltd.

Michelson interferometer vibrometer using self-correcting synthetic-heterodyne demodulation

Synthetic-heterodyne demodulation is a useful technique for dynamic displacement and velocity detection in interferometric sensors, as it can provide an output signal that is immune to interferometric drift. With the advent of cost-effective, high-speed real-time signal-processing systems and software, processing of the complex signals encountered in interferometry has become more feasible. In synthetic heterodyne, to obtain the actual dynamic displacement or vibration of the object under test requires knowledge of the interferometer visibility and also the argument of two Bessel functions. In this paper, a method is described for determining the former and setting the Bessel function argument to a set value, which ensures maximum sensitivity. Conventional synthetic-heterodyne demodulation requires the use of two in-phase local oscillators; however, the relative phase of these oscillators relative to the interferometric signal is unknown. It is shown that, by using two additional quadrature local oscillators, a demodulated signal can be obtained that is independent of this phase difference. The experimental interferometer is aMichelson configuration using a visible single-mode laser, whose current is sinusoidally modulated at a frequency of 20 kHz. The detected interferometer output is acquired using a 250 kHz analog-to-digital converter and processed in real time. The system is used to measure the displacement sensitivity frequency response and linearity of a piezoelectric mirror shifter over a range of 500 Hz to 10 kHz. The experimental results show good agreement with two data-obtained independent techniques: the signal coincidence and denominated n-commuted Pernick method.

Enamel matrix protein derivative plus synthetic bone substitute for the treatment of mandibular Class II furcation defects: a case series

Objectives: The aim of this study is to report on the treatment of mandibular Class II furcation defects with enamel matrix protein derivative (EMD) combined with a beta TCP/HA (beta-tricalcium phosphate/hydroxyapatite) alloplastic material. Method and Materials: Thirteen patients were selected. All patients were nonsmokers, systemically healthy, and diagnosed with chronic periodontitis; had not taken medications known to interfere with periodontal tissue health and healing; presented one Class II mandibular furcation defect with horizontal probing equal to or greater than 4 mm at buccal site. The clinical parameters evaluated were probing depth (PD), relative gingival margin position (RGMP), relative vertical clinical attachment level (RVCAL), and relative horizontal clinical attachment level (RHCAL). A paired Student t test was used to detect differences between the baseline and 6-month measurements, with the level of significance of .05. Results: After 6 months, the treatment produced a statistically significant reduction in PD and a significant gain in RVCAL and RHCAL, but no observable change in RGMP. RVCAL ranged from 13.77 (+/- 1.31) at baseline to 12.15 (+/- 1.29) after 6 months, with a mean change of -1.62 +/- 1.00 mm (P<.05). RHCAL ranged from 5.54 (+/- 0.75) to 2.92 (+/- 0.92), with a mean change of -2.62 +/- 0.63 mm (P<.05). After 6 months, 76.92% of the patients improved their diagnosis to Class I furcation defects while 23.08% remained as Class II. Conclusion: The present study has shown that positive clinical results may be expected from the combined treatment of Class II furcation defects with EMD and beta TCP/HA, especially considering the gain of horizontal attachment level. Despite this result, controlled clinical studies are needed to confirm our outcomes.

Transparent organic-inorganic nanocomposites membranes based on carboxymethylcellulose and synthetic clay

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

Caffeic acid esters and triterpenes of Alibertia macrophylla

A hydroalcoholic extract of the leaves of Alibertia macrophylla afforded the esters of caffeic acid and 2-phenylethanol or 2-methyl butane-1,4-diol. The leaves also contain caffeic acid. The acetone extract of the stems of A. macrophylla contain α-amyrin, β-amyrin, α-amyrenone, β-amyrenone, lupeol, lupenone and germanicone. Structural assignments were taken through spectral data analysis and physical properties. This is the first report on the chemistry of Alibertia. © 1991.

Inhibitory effect of gallic acid and its esters on 2,2'-azobis(2-amidinopropane)hodrpchloride (AAPH)-induced hemolysis and depletion of intracellular glutathione in erythrocytes

The protective effect of gallic acid and its esters, methyl, propyl, and lauryl gallate, against 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione (GSH) in erythrocytes was studied. The inhibition of hemolysis was dose-dependent, and the esters were significantly more effective than gallic acid. Gallic acid and its esters were compared with regard to their reactivity to free radicals, using the DPPH and AAPH/pyranine free-cell assays, and no significant difference was obtained. Gallic acid and its esters not only failed to inhibit the depletion of intracellular GSH in erythrocytes induced by AAPH but exacerbated it. Similarly, the oxidation of GSH by AAPH or horseradish peroxidase/H(2)O(2) in cell-free systems was exacerbated by gallic acid or gallates. This property could be involved in the recent findings on pro-apoptotic and pro-oxidant activities of gallates in tumor cells. We provide evidence that lipophilicity and not only radical scavenger potency is an important factor regarding the efficiency of antihemolytic substances.

Toxicity and loss of mitochondrial membrane potential induced by Alkyl Gallates in Trypanosoma cruzi

American trypanosomiasis or Chagas disease is a debilitating disease representing an important social problem that affects, approximately, 10 million people in the world. The main aggravating factor of this situation is the lack of an effective drug to treat the different stages of this disease. In this context, the search for trypanocidal substances isolated from plants, synthetic or semi synthetic molecules, is an important strategy. Here, the trypanocidal potential of gallates was assayed in epimastigotes forms of T. cruzi and also, the interference of these substances on the mitochondrial membrane potential of the parasites was assessed, allowing the study of the mechanism of action of the gallates in the T. cruzi organisms. Regarding the preliminary structure-activity relationships, the side chain length of gallates plays crucial role for activity. Nonyl, decyl, undecyl, and dodecyl gallates showed potent antitrypanosomal effect (IC50 from 1.46 to 2.90 μM) in contrast with benznidazole (IC50 = 34.0 μM). Heptyl gallate showed a strong synergistic activity with benznidazole, reducing by 105-fold the IC50 of benznidazole. Loss of mitochondrial membrane potential induced by these esters was revealed. Tetradecyl gallate induced a loss of 53% of the mitochondrial membrane potential, at IC50 value.

Temperature Dependent Luminescence Spectra of Synthetic and Natural Alexandrite

Results of photoluminescence measurements for natural and synthetic alexandrite (BeAl2O4:Cr3+) are presented, where the samples are excited by the 488 nm line of an Ar+ laser, at different temperatures. The main issue is the analysis of the Cr3+ transition in the chrysoberyl matrix (BeAl2O4), with major technological application as active media for laser action. Results indicate anomalous behavior of Cr3+ transition depending on the measurement temperature. A simple model to explain the phenomena is suggested.