Utilización de análogos fluorados de la feromona sexual de Sesamia nonagrioides Lef. como inhibidores de su actividad biológica

Se ha estudiado el papel, como inhibidores de la acción feromonal, de determinados fluoroderivados, análogos estructurales del acetato de (Z)-l 1-hexadecenilo, componente principal de la feromona sexual del noctuido Sesamia nonagrioides Lef. Dichos compuestos fueron los análogos fluoroacetato (mono, di y trifluoroacetato de (Z)-l 1-hexadecenilo) y la trifluorometilcetona análoga [(Z)-1,1,1 -trifluoro-14-nonadecen-2-ona]. La acción inhibidora fue evaluada a partir de los resultados de actividad electrofisiológica (pruebas de electroantenograma, EAG), de estudios de comportamiento en pruebas de túnel de viento y de pruebas de capturas en campo. Los acetatos fluorados, especialmente el mono y el trifluoracetato, se mostraron como buenos inhibidores de la acción atrayente de la feromona en los tres tipos de pruebas realizadas, mientras que la trifluorometilcetona análoga mostró una actividad mucho menor.

Actividad biológica de la azadiractina sobre Nezara viridula (L.)

Se ha estudiado la acción reguladora del desarrollo de diferentes dosis de azadiractina, aplicadas tópicamente sobre ninfas Nezara viridula (L.) de 5 o estadio. Igualmente se ha evaluado la fecundidad y la fertilidad de adultos, machos y hembras, procedentes de ninfas tratada con dicho compuesto a varias dosis subletales. Con dosis iguales o superiores a 200 ng/insecto se alcanzaron porcentajes de mortalidad en la muda superiores al 85 %, estos adultos poseían además un elevado número de características ninfales y resultaron inviables. A dosis inferiores, desde 50 a 2 ng/insecto, se obtuvo un porcentaje de adultos aparentemente normales superior al 50%. El efecto esterilizante eductor de fecundidad de la azadiractina se observo tratando hembras y machos con dosis de 5 ng/insecto. El número de huevos/insecto tratado fue significativamente inferior al testigo control. Finalmente azadiractina a dosis de 1 (J-g/cm^ dispuesta sobre el área de puesta, mostró un claro efecto disuasor de la oviposición sobre hembras fecundadas de la especie.

Fixação de frutos de limeiras ácidas 'Tahiti' aneladas e tratadas com ácido giberélico

O objetivo deste trabalho foi avaliar o efeito do ácido giberélico (GA3) e do anelamento de ramos sobre a abscisão de estruturas florais e o pegamento de frutos em limeira ácida 'Tahiti'. Para as variáveis relacionadas à abscisão de estruturas reprodutivas, o esquema experimental foi em parcelas subdivididas no tempo, com o fatorial 4 x 3 nas parcelas. Quanto ao pegamento de frutos, o esquema experimental foi apenas o fatorial 4 x 3. O primeiro fator foi a aplicação de GA3 em quatro concentrações (0; 7; 14 e 21 mg/L), e o segundo, as duas épocas de anelamento: no início do florescimento (AIF) e a um mês após o florescimento (AMAF), mais a testemunha sem anelamento (SA). O delineamento experimental foi em blocos casualizados (DBC), com cinco repetições. Verificou-se que o GA3 não inibe a abscisão das estruturas reprodutivas e não afeta o pegamento dos frutos de limeira ácida 'Tahiti'. O anelamento reduziu a abscisão das estruturas reprodutivas. O pegamento de frutos nas plantas com o AIF foi 15,66% e com o AMAF, de 16,11%, o que significa aumentos de 220% e 229%, respectivamente, em relação às plantas SA, que tiveram pegamento de 4,89%.

Induction chemoradiation in stage IIIA/N2 non-small-cell lung cancer: a phase 3 randomised trial.

BACKGROUND: One of the standard options in the treatment of stage IIIA/N2 non-small-cell lung cancer is neoadjuvant chemotherapy and surgery. We did a randomised trial to investigate whether the addition of neoadjuvant radiotherapy improves outcomes. METHODS: We enrolled patients in 23 centres in Switzerland, Germany and Serbia. Eligible patients had pathologically proven, stage IIIA/N2 non-small-cell lung cancer and were randomly assigned to treatment groups in a 1:1 ratio. Those in the chemoradiotherapy group received three cycles of neoadjuvant chemotherapy (100 mg/m(2) cisplatin and 85 mg/m(2) docetaxel) followed by radiotherapy with 44 Gy in 22 fractions over 3 weeks, and those in the control group received neoadjuvant chemotherapy alone. All patients were scheduled to undergo surgery. Randomisation was stratified by centre, mediastinal bulk (less than 5 cm vs 5 cm or more), and weight loss (5% or more vs less than 5% in the previous 6 months). The primary endpoint was event-free survival. Analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00030771. FINDINGS: From 2001 to 2012, 232 patients were enrolled, of whom 117 were allocated to the chemoradiotherapy group and 115 to the chemotherapy group. Median event-free survival was similar in the two groups at 12·8 months (95% CI 9·7-22·9) in the chemoradiotherapy group and 11·6 months (8·4-15·2) in the chemotherapy group (p=0·67). Median overall survival was 37·1 months (95% CI 22·6-50·0) with radiotherapy, compared with 26·2 months (19·9-52·1) in the control group. Chemotherapy-related toxic effects were reported in most patients, but 91% of patients completed three cycles of chemotherapy. Radiotherapy-induced grade 3 dysphagia was seen in seven (7%) patients. Three patients died in the control group within 30 days after surgery. INTERPRETATION: Radiotherapy did not add any benefit to induction chemotherapy followed by surgery. We suggest that one definitive local treatment modality combined with neoadjuvant chemotherapy is adequate to treat resectable stage IIIA/N2 non-small-cell lung cancer. FUNDING: Swiss State Secretariat for Education, Research and Innovation (SERI), Swiss Cancer League, and Sanofi.

Final results of the SAKK 16/00 trial: a randomized phase III trial comparing neoadjuvant chemoradiation to chemotherapy alone in stage IIIA/N2 non-small cell lung cancer (NSCLC).

Aim: One standard option in the treatment of stage IIIA/N2 NSCLC is neoadjuvant chemotherapy followed by surgery. We investigated in a randomized trial whether the addition of neoadjuvant radiotherapy would improve the outcome. Here we present the final results of this study. Methods: Patients (pts.) with pathologically proven, resectable stage IIIA/N2 NSCLC, performance status 0-1, and adequate organ function were randomized 1:1 to chemoradiation (CRT) with 3 cycles of neoadjuvant chemotherapy (cisplatin 100 mg/m2 and docetaxel 85 mg/m2 d1, q3weeks) followed by accelerated concomitant boost radiotherapy (RT) with 44 Gy in 22 fractions in 3 weeks, or neoadjuvant chemotherapy alone (CT), with subsequent surgery for all pts. The primary endpoint was event-free survival (EFS). Results: 232 pts. were randomized in 23 centers, the median follow-up was 53 months. Two thirds were men, median age was 60 years (range 37-76). Histology was squamous cell in 33%, adenocarcinoma in 43%. Response rate to CRT was 61% vs. 44% with CT. 85% of all pts. underwent surgery, 30-day postoperative mortality was 1%. The rate of complete resection was 91% (CRT) vs. 81% (CT) and the pathological complete remission (pCR) rate was 16% vs. 12%. The median EFS was 13.1 months (95% CI 9.9 - 23.5) for the CRT group vs. 11.8 months (95% CI 8.4 - 15.2) in the CT arm (p 0.665). The median overall survival (OS) with CRT was 37.1 months (95% CI 22.6 -50), with CT 26.1 months ( 95% CI 26.1 - 52.1, p 0.938). The local failure rate was 23% in both arms. In the CT arm 12 pts. were given postoperative radiotherapy (PORT) for R1 resection, 6 pts. received PORT in violation of the protocol. Pts. with a pCR, mediastinal downstaging to ypN0/1 and complete resection had a better outcome. Toxicity of chemotherapy was substantial, especially febrile neutropenia was common, whereas RT was well tolerated. Conclusions: This is the first completed phase III trial to evaluate the role of induction chemoradiotherapy and surgery, in comparison to neoadjuvant CT alone followed by surgery. RT was active, it increased response, complete resection and pCR rates. However, this failed to translate into an improvement of local control, EFS or OS. Notably, surgery after induction treatment was safe, including pneumonectomy. The overall survival rates of our neoadjuvant regimen are very encouraging, especially for a multicenter setting. Disclosure: M. Pless: Advisory Board for Sanofi; R. Cathomas: Advisory Board Sanofi D.C. Betticher: Advisory Board Sanofi. All other authors have declared no conflicts of interest.

Estudos de QSAR baseados em dados de atividade biológica obtidos por microcalorimetria: III interação de m-alcoxifenóis e p-hidroxibenzoatos de alquila com Escherichia coli

QSAR studies based on flow microcalorimetric bioassay data for interaction of homologous series of m-alkoxyphenols and p-hydroxybenzoates with E. coli cells were carried out applying factorial design. Results for both series showed a linear relationship between log(dose)max and log Po/w. Analysis of these data allows the identification of contributions toward the derived bioactivity from the parent structures (the molecule minus n-CH2 groups present in the side-chain) and the lipophilic groups, CH2. These results are discussed with respect to drug quantitative structure-relationship.

Utilização do resíduo líquido de indústria de processamento de suco de laranja como meio de cultura de Penicillium citrinum: depuração biológica do resíduo e produção de enzima

Penicillium citrinum grown in orange juice processing wastes medium under continuous agitation was studied in order to establish optimal conditions (incubation period, incubation temperature, initial pH and nitrogen addition) for biomass and ribonuclease production, as well as, biological depuration of the wastes. Nitrogen addition to wastes medium increased the biomass and ribonuclease production and provides COD reduction. The soy meal shows to be the best nitrogen source. The conditions for a more favorable enzyme and biomass production and COD reduction were initial pH 6.0 and temperature of 27°C. The maximum value obtained for these parameters on optimal conditions of cultivation was 11 U/mL of enzyme, 4 mg/mL of biomass (dry matter) and 55% of COD reduction, in 96 hours of incubation.

Proposição, validação e análise dos modelos que correlacionam estrutura química e atividade biológica

The present paper aims to bring under discussion some theoretical and practical aspects about the proposition, validation and analysis of QSAR models based on multiple linear regression. A comprehensive approach for the derivation of extrathermodynamic equations is reviewed. Some examples of QSAR models published in the literature are analyzed and criticized.

Métodos de preparação e atividade biológica do ácido quinolínico e derivados

In 1981 2,3-pyridine dicarboxylic acid (quinolinic acid) was discovery to be a selective agonist for the N-methyl -D-aspartic acid (NMDA) receptor. As a consequence it possesses neurotoxic activity resulting from overstimulation of the receptor. Quinolinic acid is implicated as an etiological factor in a range of neurodegenerative disease including AIDS related dementia, Huntington´s disease and Lyme disease. In the design of novel therapies to treat these diseases, some molecules have been identified as an important target. In this paper we described different methods to prepare quinolinic acid and derivatives.

Fixação de nitrogênio: estrutura, função e modelagem bioinorgânica das nitrogenases

Biological nitrogen fixation, catalyzed by nitrogenases, contributes about half of the nitrogen needed to global agriculture. For forty years synthetic chemists and theoreticians have tried to understand and model the structure and function of this important metalloenzyme. Ten years after the first report on the crystal structure of the MoFe protein, scientists still have not been able to synthesize a chemical equivalent of the FeMo cofactor nor the structure knowledge revealed the key to its catalytic activity. This paper with 104 references presents a review of the most relevant advances in chemical nitrogen fixation and their relation with the nitrogenases.

Adsorção de As, Cu, Pb e Cr na avaliação da capacidade de fixação de metais por resíduo de mineradoras de ferro

Two samples of residues from iron mining plants have been investigated for their retention capacity of As, Cu, Cr, and Pb. The sample with the higher content of iron oxides showed the highest capacity to retain metals. The adsorption affinity series changes from Pb>Cu>Cr~As to As>Pb>Cu>Cr or As>Cu>Cr>Pb, depending on the material and the concentration of the initial solution. In the competitive environment, the Pb adsorption decreases and the As, Cu and Cr adsorption increases. Sequential extraction procedures, carried out after adsorption batch experiments, showed that the most important adsorption process occurs in the oxide fraction and that the major part of the absorbed metal is remobilized from exchangeable and oxide fractions.

Tiossemicarbazonas: métodos de obtenção, aplicações sintéticas e importância biológica

Thiosemicarbazones are a class of compounds known by their chemical and biological properties, such as antitumor, antibacterial, antiviral and antiprotozoal activity. Their ability to form chelates with metals has great importance in their biological activities. Their synthesis is very simple, versatile and clean, usually giving high yields. They are largely employed as intermediates, in the synthesis of others compounds. This article is a survey of some of these characteristics showing their great importance to organic and medicinal chemistry.

Ocorrência e atividade biológica de quassinóides da última década

Quassinoids, the bitter principles of the Simaroubaceae family, are a group of structurally complex and highly oxygenated degraded triterpenes. They are divided into five groups according to their basic skeleton, C-18, C-19, C-20, C-22 and C-25. In recent years, attention has been focused on quassinoids because several of them have shown promising biological activities. This paper features a review of some characteristics of these compounds, updating known information with discoveries from the last decade and covering chemical structures, basic skeletons, occurrence in genus and species, besides detailed studies of biological activities such as antitumor, antimalarial, phytotoxic, antifeedant, insecticidal, anti-inflammatory and antiulcer.

Composição química e atividade biológica das folhas e frutos de Triphasia trifolia

The chemical composition of the essential oils from leaves and fruits of Triphasia trifolia was analyzed by GC-FID and GC-MS. The major constituents of oil obtained from leaves were sabinene (35.4%) and myrcene (34.1%), while the prevalent compounds in oil from fruits were sabinene (37.2%), beta-pinene (23.95) and gamma-terpinene (16.3%). Both oils showed moderate antimicrobial activity. The fruit decoction was also investigated leading to the isolation of the coumarins isopimpinelin, (R)-byakangelicin and (S)-mexoticin. From leaves were isolated the coumarins (R)-byakangelicin, aurapten, (S)-mexoticin, isosibiricin, isomerazin and coumurrayin and the flavonoid vitexin. All coumarins showed cholinesterase inhibition on TLC tests.