Spectrophotometric determination of cefaclor in pharmaceutical preparations

A simple spectrophotometric method is proposed for the determination of cefaclor. The method involves alkaline hydrolysis of the drug in ammonia buffer solution at pH 10 to yield diketopiperazine-2,5-dione derivative and subsequent measurement at 340 nm. Beer's law is obeyed in the concentration range 1.8 - 55 mg/mL. The proposed method was successfully applied to the determination of cefaclor in pharmaceutical formulations.

Estudos da eletrodeposição de metais em regime de subtensão

This work reviews recent studies of underpotential deposition (UPD) of several metals on Pt and Au substrates performed in the Grupo de Materiais Eletroquímicos e Métodos Eletroanalíticos (IQSC -- USP, São Carlos). The UPD Cu, Cd and Pb on Pt were analysed in terms of their influence in the oxygen evolution reaction. Partial blockage of surface active sites, promoted by Pb ad-atoms, resulted in a change from water to hydrogen peroxide as the final product. The Ag UPD on Pt and Au substrates was also discussed in this work. A detailed model of charge calculation for Ag monolayer was developed and confirmed by the rotating ring-disk data. The partial charge transfer in UPD studies was analysed in the Cd/Pt and Cd/Au systems and a value of 0.5 was found for the adsorption electrovalence of Cd ad-ions. The Sn/Pt UPD systems were studied from the point of view of the valences of metallic ions in solution. The deposition from Sn(IV) generates a full monolayer with a maximum occupation of approximately 40% of the surface active sites (340 µC cm-2) plus 105 µC cm-2 of Hads (half monolayer). Changing the metallic ion for Sn(II), it was possible to deposit a full monolayer (210 µC cm-2) without any detectable Hads. Finally, the effect of anions was discussed in the Zn/Pt and Zn/Au systems. Here, the hydrogen evolution reaction (her) and the hydrogen adsorption/desorption were used in order to investigate the maximum coverage of the surface with Zn ad-atoms. The full monolayer, characterised by the complete absence of Hads, was achieved only in 0.5 M HF solutions.

Geração sonoquímica de oxidantes em solução aquosa saturada de tetracloreto de carbono

In this work the CCl4 degradation in aqueous solution by sonication with 40 kHz commercial ultrasonic bath was investigated. Sonochemical degradation of CCl4 occur by the cleavage of C-Cl bond into the cavitation bubbles. Oxidation reactions and the pH decreasing in the bulk solution during sonication were attributed to chlorine radicals produced by CCl4 sonolysis, leading to increase the chloride concentration. The formation of oxidizing agents was evaluated employing I- and Fe2+ ion solutions, converted to I2 and HIO, and Fe3+, respectively. The amount of chloride and hydronium ions produced after 3 min of irradiation was 11.52 and 12.19 mmol, respectively, suggesting that the same reaction was involved to produce these ions. Fe2+ oxidation and the pH variation were monitored to estimate chlorine radical formation rate in the presence (0.107 mumol s-1) and absence (0.092 mumol s-1) of metallic ion during the first minute of sonication.

Piccola sarabanda

Soitinnus: piano.

Lounais-Suomen meriklusteri 2009

Lounais-Suomen meriklusteri kattaa Varsinais-Suomen ja Satakunnan maakunnat. Ensimmäinen alueellisen meriklusterin perusselvitys valmistui vuonna 2006. Tämän tutkimusraportin pääsisältönä on Lounais-Suomen meriklusterin taloudellisten ja toiminnallisten perustunnuslukujen päivitys sekä niiden esittäminen aikasarjana vuodesta 2005 vuoteen 2008. Tilastollisen aineiston perusvuosi on 2008. Varsinais-Suomessa ja Satakunnassa toimii vajaat 340 meriklusteriin kuuluvaa yritystä, joilla on alueella noin 400 toimipaikkaa. Näistä Satakunnassa sijaitsee reilut 100 ja Varsinais-Suomessa vajaat 300. Määrä on hieman pienempi kuin perusselvityksen aikaan, mikä johtuu osin yritysfuusioista ja osin siitä, että jotkut yritykset eivät enää toimi merisektorilla. Meriklusterin merkitys on edelleen erittäin suuri Lounais-Suomessa ja sen suhteellinen osuus on säilynyt samassa suuruusluokassa kuin vuonna 2006. Meriklusteriyritysten Lounais-Suomen toimipaikkojen yhteenlaskettu liikevaihto vuonna 2008 oli noin 4,3 miljardia euroa, josta noin 3,5 miljardia euroa tuli suoraan yritysten merisektorin liiketoiminnasta. Meriklusteriyritykset työllistävät alueella yhteensä noin 17 000 henkilöä, joista merisektori työllistää suoraan noin 12 700 henkilöä. Meriklusterin osuus kaikista Varsinais-Suomen ja Satakunnan työllisistä on noin 5,4 prosenttia. Välilliset työllisyysvaikutukset huomioiden meriklusteri työllistää Lounais-Suomessa vähintään 27 000 henkilöä eli noin 8,2 prosenttia alueen työllisistä. Lounais-Suomen osuus koko Suomen meriklusterista vaihtelee eri pääryhmittäin. Liikevaihdon mukaan mitattuna telakkatoiminnassa osuus on noin 85 prosenttia, varustamotoiminnassa noin 15 prosenttia ja satamissa noin 25 prosenttia. Karkeasti arvioituna kaikkien meriklusteriyritysten merisektorin toimintojen osalta Lounais-Suomen toimipaikkojen liikevaihdon osuus on noin 30–40 prosenttia. Aikasarjatarkastelu osoittaa, että meriklusterin positiivinen kehitys taittui vuonna 2008. Liikevaihdon kasvu hiipui, kuten myös henkilöstömäärän kasvu. Elo-syyskuun 2009 tilanne osoittaa, että henkilöstömäärä on laskenut edellisestä vuodesta. Kyselyyn vastanneista yrityksistä lähes kolmannes oli jo joutunut lomauttamaan henkilöstöään. Liiketoiminnan tulevaisuudennäkymät ovat nyt huomattavasti synkemmät kuin vuonna 2006. Vain hieman yli 10 prosenttia vastaajista arvioi näkymien parantuvan tulevan vuoden sisällä. Hieman yli puolet odottaa tilanteen säilyvän ennallaan ja lähes 30 prosenttia uskoo näkymien edelleen heikkenevän. Meriteollisuuden näkymät ovat kaikkein huonoimmat ja näkymiä leimaavat monet erityyppiset epävarmuustekijät. Merikuljetukset ja satamatoiminnot puolestaan ovat suoraan riippuvaisia yleisestä taloudellisesta tilanteesta ja siinä tapahtuvat muutokset heijastuvat niihin varsin nopeasti.

De caussis florescentis & marcescentis reipublicae litterariae

Dedicatio: Claudius Ekeblad, Carolus Wilhelmus von Düben, Christophorus Clewberg, Petrus Adrianus Gadd.

Le Constitutionnel : journal politique et littéraire

1816/12/05 (Numéro 340).

Estabilização do ácido lipoico via encapsulação em nanocápsulas poliméricas planejadas para aplicação cutânea

This work reports the development of polymeric nanocapsules containing lipoic acid prepared by interfacial deposition of poli(ε-caprolactona). The suspensions showed acid pH and encapsulation efficiencies from 77 to 90%. Zeta potential values were from -7.42 to -5.43 mV and particle sizes were lower than 340 nm with polidispersion lower than 0.3. The stability of nanocapsules within 28 days was evaluated in terms of pH, lipoic acid content, diameter, size distribution, zeta potential and measurements of relative light backscattering. The stability of formulations containing free lipoic acid was also evaluated. Nanoencapsulation drastically improved the physico-chemical stability of lipoic acid.

An testamenta sint juris naturalis?

Invocatio: I.N.D.O.M.

Composição química e atividade anticolinesterásica de uma fração ativa do extrato de folhas de Citrus limon (L.) Burm

This paper describes the chemical composition and acetylcholinesterase inhibition of an active chromatographic fraction of the EtOAc extract of Citrus limon leaves. The composition of the active fraction presented a mixture of two coumarins, 5,8-dimethoxy-psoralen and 5,7- dimethoxycoumarin, identified by ¹H and ¹³C NMR data analysis, including DEPT, COSY, HMBC and HSQC experiments. It was also demonstrated that this mixture presents qualitative and quantitative AChE inhibition. In vitro studies indicated a CE50 value of 340 µg/mL with 95% of confidence. In vivo studies (10 and 25 mg/kg) revealed inhibition of 30.09 and 30.06% of AChE activity in relation to neostigmine, respectively.

Detecção de Closterovirus em videira e caracterização parcial de um isolado do Grapevine leafroll-associated virus 3

O enrolamento da folha da videira (Vitis spp.) é uma doença causada por até oito vírus, Grapevine leafroll-associated virus (GLRaV) 1 a 8, sorologicamente distintos e associados ao floema de videiras infetadas. Neste trabalho, foram detectados GLRaV-1 e -3 por DAS-ELISA em 6,9 e 14,7% das amostras analisadas, respectivamente, e provenientes de duas importantes regiões vitícolas do Brasil (Serra Gaúcha e Vale do São Francisco). Os GLRaV-2, -5 e -7 não foram detectados. O GLRaV-3 também foi detectado por dot-ELISA e western blot, observando-se a provável proteína capsidial com cerca de 36 kDa. Um fragmento de 340 pb, compreendendo o terminal 3' do gene da polimerase viral de GLRaV-3, foi amplificado por PCR e seqüenciado. As seqüências de nucleotídeos e aminoácidos deduzidos deste isolado apresentaram alta homologia, 95,0 e 97,1%, respectivamente, com outro isolado de GLRaV-3 (NY1).

Variability of the 3' terminal of the polymerase gene of Grapevine leafroll-associated virus 3 isolates from Vale do São Francisco, Brazil

Many viral diseases, including leafroll, which is of great economic importance, affect grapevines (Vitis spp.). A complex of eight viruses [Grapevine leafroll-associated virus (GLRaV) -1 to 8] is associated with this disease. The objective of this study was to compare the variability of the 3' terminal region of the polymerase gene of three isolates of GLRaV-3 (Grapevine leafroll-associated virus-3), from Submédio do Vale do Rio São Francisco (Petrolina-PE) with that of other isolates available at the GenBank, including an isolate from North America and another from Southern Brazil. The viral RNA was extracted from three infected ELISA reactive plants and a fragment of 340 bp was amplified, by RT-PCR, using primers that recognize that portion of the polymerase gene found between nucleotides 8267 and 8606. The three isolates from Vale do Rio São Francisco named Pet-1, Pet-2 and Pet-3, showed similarities ranging from 98% and 94%, respectively to the isolates from North America (AF037268) and Southern Brazilian (AF438411). Considering the whole genome, the main variation found was one amino acid change at position 2766 (F2766Y). These preliminary data indicate the existence of a natural variation among GLRaV-3 isolates from grapevines. This could be due to the vegetative propagation and long cycle of the plant, associated with the error-prone nature of RNA-dependent RNA polymerase.

Use of spectrophotometry as a tool to quantify the sporulation of Penicillium allii in garlic lesions

A technique to measure the concentration of Penicillium allii conidia in damp chamber experiments by spectrophotometry was developed. A negative linear correlation (R²=0.56) was observed between transmittance at 340 nm and the concentration of P. allii conidia in water agar 0.05%. The equation that relates transmittance (T) with concentration (conidia mL-1) (y) is: y = 9.3 10(6) - 86497 T. The method was assayed by inoculating 43 P. allii strains in two garlic cultivars. The method proved to be more rapid than the traditional use of a hemocytometer with an improved accuracy. The CV of the number of conidia per hemocytometer reticule was of 35.04%, while the transmittance CV was of 2.73%. The extreme values chosen for T were 40 and 80 because the sensitivity of the method decreased when concentrations of conidia were out of this range.

Quimiometria como ferramenta analitica para definição das condiçoes de ensaio da enzima peroxidase de soja

Enzimas Peroxidases são heme-proteínas encontradas nos diferentes organismos vivos, especialmente vegetais, apresentam importante papel fisiológico/bioquímico como proteção contra microorganismos invasores. A soja, um dos mais importantes produtos para o agronegócio brasileiro apresenta na casca de suas sementes (subproduto) alta atividade de peroxidase, denominada soybean peroxidase,com potencial de utilização em métodos analíticos clínicos. A proposta do trabalho foi aplicar o planejamento fatorial para otimização das condições extração da enzima, definição das condições ótimas de atividade (pH e temperatura), utilizando metodologia de superfície de resposta. Os dados obtidos com clara definição foram: i) extração em pó cetonico, ii) meio reacional: pH 3,3, volume da amostra contendo a enzima 330 µL - 340 µL, peróxido de hidrogênio 4,2 mmol.L-1 150 µL, tempo de reação 20 segundos, temperatura 50º C, substrato guaiacol 30mmol.L-1 300 µL, e 0,1 mol.L-1 de NaCl. O uso da dessa metodologia para definição das condições de extração e estudos cinético-enzimáticos da peroxidase de soja foram eficientes e mais precisos, comparado a metodologia de variações/repetições (tentativa e erro).