7 research outputs found
Catalogue of Mesozoic radiolarian genera. Part 1: Triassic
No full textO'Dogherty, Luis, Carter, Elizabeth S., Dumitrica, Paulian, Goriččan, Špela, Wever, Patrick De, Hungerbühler, Alexandre, Bandini, Alexandre Nicolas, Takemura, Atsushi (2009): Catalogue of Mesozoic radiolarian genera. Part 1: Triassic. Geodiversitas 31 (2): 213-270, DOI: 10.5252/g2009n2a3, URL: http://www.bioone.org/doi/abs/10.5252/g2009n2a
Asymmetry of the ring of the Saturnalidae (entactinarian Radiolaria): Causes and morphological and evolutionary consequences
No full textMono- and Dicyrtid Nassellaria (Radiolaria) from the Upper Carnian of the Sorgun Ophiolitic Mélange, Southern Turkey and Kopría Mélange, Rhodes, Greece = Radiolaires nassellaires mono- et dicyrtides du Carnien supérieur du Mélange Ophiolitique de Sorgun, Turquie Méridionale et du Mélange de Kopría, Rhodes, Grèce
No full textFour new genera (Circopoulpus nov. gen., Aropeon nov. gen., Tekinium nov. gen., Caponabolella nov. gen.) and 19 new characteristic mono-
and dicyrtid Nassellarian species are described herein from two of the most diverse and best preserved Carnian (Late Triassic) radiolarian faunas
of the world, which are the lower Tuvalian sequence of the Sorgun Ophiolitic Mélange, southern Turkey, and the Kopría Mélange, Rhodes, Greece
Ammonoid biostratigraphy of the Early Spathian Columbites parisianus zone (Early Triassic) at Bear Lake Hot Springs, Idaho
No full textWe review paleontological work on the Meekoceras beds (middle Smithian) and Columbites beds at theBear Lake Hot Springs locality. The geology of the general area as well as the stratigraphy of the ThaynesFormation along the Hot Springs Ridge is discussed. We present a new detailed biostratigraphic scheme containingfour unique ammonoid horizons (in ascending order, Yvesgalleticeras montpelierense bed, Columbites parisianusbed, Arctomeekoceras popovi bed and Columbites isabellae beds) within the Columbites parisianus Zone at thissite and briefly apply the scheme to the classic Paris Canyon section on the west side of the Bear Lake Valley.Photographs and figures are given showing the locations of sections and fossiliferous horizons at the Bear Lake HotSprings and Paris Canyon sites from which ammonoids have been collected by the first author. We also comparethe biostratigraphic fossiliferous horizons of this work to the biochronologic scheme of Guex et al. (2010), whichis updated, based on new information provided in this report
Estudo da redução de acetofenonas utilizando biocatalizadores da região amazônica para obtenção de substâncias com elevada pureza enantiomérica de interesse farmacológico
No full textThe search for new biocatalysts is of great interest to the biotechnology and pharmaceutical
industries. Enzymes are substances found in plants and in microorganisms, and present
themselves as excellent catalysts due to their ability to synthesize chemical substances that
are biologically active. Some of these compounds are widespread in drug production, such as
enantiomerically pure alcohols. Its synthesis can be carried out using whole cells of vegetables
or microorganisms in the asymmetric bioreduction reactions of ketones. Considering the vast
biodiversity present in the Amazon region and the need for research in this area, this work
aimed to bioprospect new biocatalysts, in order to evaluate its potential on the enantioselective
bioreduction reactions of acetophenones. The vegetables Daucus carota (carrot), Zingiber
officinale (ginger), Manihot esculenta (cassava), Ipomoea potatoes (sweet potato), Solanum
melongena (eggplant), and different parts of Amazon plants Cissus gongylodes (Cipó kupá),
Solanum sessiliflorum (cubiu) and Xanthosoma violaceum were tested. Different fungi strains
of the genus Aspergillus were also tested. The fungi were evaluated regarding its production
of alcohol dehydrogenase (ADH), enzyme envolved in the bioreduction reactions. The reactios
of p-aminoacetophenone, p-hydroxyacetophenone, p-nitroacetophenone and p-methoxy-mnitroacetophenone
were evaluated in three reaction systems: organic (hexane), biphasic
(hexane and buffer), and aqueous (buffer). The fungi were cultivated for a period of five days,
then were filtered and set to dry. For the vegetables, an assepsia step was performed and then
they were cut into small pieces. Thereafter, 50 mg of the dried mycelia or 10 g of the sliced
vegetables were added to the reaction medium (40 mL) containing the previously solubilized
carbonyl substrates. After 24 hours, the reaction was analyzed by gas chromatography
equipped with a chiral column. All tested fungi produced ADH, and 5 strains were selected for
the biocatalytic reactions. Fungus A. brasiliensis presented the best convertion percentages
for the reduction of p-nitroacetophenone (c = 53.7%), and p-methoxy-m-nitroacetophenone (c
= 32.2%), both in a biphasic system. In organic medium, the strain was able to reduce the paminoacetophenone
(c = 11%). All these reactions presented enantiomeric excess > 99%.
Among the tested vegetables, the reduction of p-aminoacetophenone mediated by the tuber
of purple taioba presented an outstanding result (c = 93.6%) of only one chiral alcohol, in
organic medium. For the reduction of p-hydroxyacetophenone, the carrot was the best
biocatalyst, forming only one enantiomer, with 45.5% conversion in biphasic medium. For pnitroacetophenone,
the cipó-kupá promoted the formation of only one product with 13.9%
conversion in the two-phase medium. For p-methoxy-m-nitroacetophenone, cassava and
purple taioba tuber provided 34.6% conversion to the chiral alcohol in aqueous medium. To
evaluate the influence of reaction time, substrate concentration and pH over the conversion
values, it was performed an experimental design for some of the biocatalytic systems. For A.
brasiliensis, time and pH were the variables that significantly influenced chiral alcohol
production (p > 0.5), with the shortest time and the highest pH leading to the highest conversion
rates. For the tests performed with the vegetables, sweet potato was directly influenced by pH
during the reduction reaction of p-nitroacetophenone (p > 00.5). In this work were obtained
results that demonstrate the biocatalytic potential of fungi of the genus Aspergillus and of
several plants found in the Amazon region, especially purple taioba. It is expected that
researchs on this area can be carried out to explore the biotechnological potential of these
organisms with an emphasis on biocatalysis.
Key words: Biocatalysis, Aspergillus, Vegetables, Biorreduction, Enantioselectivity.A busca por novos biocatalisadores é de grande interesse para a indústria biotecnológica e
farmacêutica. As enzimas são substâncias encontradas em vegetais e microrganismos e se
apresentam como excelentes catalisadores devido à sua capacidade de sintetizar substâncias
químicas biologicamente ativas. Algumas destas substâncias são bastante difundidas na
produção de fármacos, como os álcoois enantiomericamente puros. Sua síntese pode ser
realizada utilizando células integras de vegetais ou de microrganismos em reações de
biorredução assimétrica de cetonas. Diante da vasta biodiversidade presente na região
amazônica e a necessidade de investigações nesta área, este trabalho teve como objetivo
realizar a bioprospecção de novos biocatalisadores, a fim de avaliar seu potencial em reações
de biorredução enantiosseletiva de acetofenonas substituídas. Foram testados os vegetais
Daucus carota (cenoura), Zingiber officinale (gengibre), Manihot esculenta (mandioca),
Ipomoea batatas (batata doce), Solanum melongena (berinjela), e as diferentes partes das
plantas amazônicas Cissus gongylodes (cipó kupá), Solanum sessiliflorum (cubiu) e
Xanthosoma violaceum (taioba roxa), além de diferentes cepas de fungos do gênero
Aspergillus. Os fungos foram avaliados quanto à produção de álcool desidrogenase (ADH),
enzima envolvida nas reações de biorredução. As reações de redução da paminoacetofenona,
p-hidroxiacetofenona, p-nitroacetofenona e p-metoxi-m-nitroacetofenona
foram avaliadas em três sistemas reacionais: orgânico (hexano), bifásico (hexano e tampão)
e aquoso (tampão). Os fungos foram cultivados por um período de cinco dias, foram filtrados
e os micélios postos para secar. Para os vegetais foi realizada uma etapa de asepssia e em
seguida estes foram cortados em pequenos pedaços. Após isto 50 mg dos micélios secos ou
10 g dos vegetais cortados foram adicionados ao meio reacional (40 mL) contendo o substrato
carbonílico previamente solubilizado. Após 24 horas, a reação foi analisada por cromatografia
em fase gasosa equipada com coluna quiral. Todos os fungos produziram ADH, sendo 5
cepas selecionadas para as reações biocatalíticas. O fungo Aspergillus brasiliensis foi o que
apresentou os melhores percentuais de conversão para as reações de redução da pnitroacetofenona
(c = 53,7%), p-metoxi-m-nitroacetofenona (c = 32,2%) ambas em sistema
bifásico, e em meio orgânico a cepa foi capaz de reduzir a p-aminoacetofenona (c = 11%),
sendo que todas estas reações apresentaram valores de excesso enantiomérico >99%.
Dentre os vegetais, destacou-se a reação de redução da p-aminoacetofenona mediada pelo
tubérculo da taioba roxa que promoveu a maior conversão ao produto enantiomericamente
puro (93,6%) em meio orgânico. Na redução da p-hidroxiacetofenona, a cenoura foi o melhor
biocatalisador, formando apenas um enantiômero, com 45,5% de conversão em meio bifásico.
Para a p-nitroacetofenona, o cipó-kupá promoveu a formação de apenas um produto com
13,9% de conversão em meio bifásico. Para a p-metoxi-m-nitroacetofenona, a mandioca e o
tubérculo da taioba roxa forneceram 34,6% de conversão ao álcool quiral em meio aquoso. A
fim de avaliar a influência do tempo de reação, da concentração do substrato e do pH sobre
as conversões a produto, foi realizado um planejamento experimental para alguns sistemas
biocatalíticos. Para o A. brasiliensis o tempo e o pH foram as variáveis que influenciaram
significativamente a obtenção do álcool quiral (p > 0,05), sendo que o menor tempo e o maior
pH levaram às maiores percentagens de conversão. Dos ensaios realizados com os vegetais,
a batata doce foi influenciada diretamente pelo pH durante a reação de redução da pnitroacetofenona.
Neste trabalho foram obtidos resultados que demonstram o potencial
biocatalítico dos fungos do gênero Aspergillus e de vegetais encontrados da região
amazônica, com destaque para a taioba roxa. Espera-se com estes resultados que mais
pesquisas sejam realizadas a fim de se explorar o potencial biotecnológico destes organismos
com ênfase na biocatálise.
Palavras-chave: Biocatálise, Aspergillus, Vegetais, Biorredução, Enantiosseltividade
Fatal subarachnoid hemorrhage following ischemia in vertebrobasilar dolichoectasia
No full textVertebrobasilar dolichoectasia (VBD) is a chronic disorder with various cerebrovascular and compressive manifestations, involving subarachnoid hemorrhage (SAH). Occurrence of SAH shortly after worsening of clinical VBD symptoms has occasionally been reported. The goal of the study was to examine this association, in particular its pathophysiology, clinical precursor signs, time course, and outcome. To this end, in a retrospective multicenter study, we analyzed 20 patients with VBD and SAH in regard to preceding clinical symptoms, presence of vertebrobasilar thrombosis and ischemia, outcome and neuropathological correlates. Median age of the 7 female and 13 male patients was 70 years (interquartile range [IQR] 18.3 years). Fourteen patients (70%) presented with new or acutely worsening posterior fossa signs at a median of 3 days prior to SAH (IQR 2, range 0.5-14). A thrombus within the VBD was detected in 12 patients (60%). Thrombus formation was associated with clinical deterioration (χ 2 = 4.38, P = 0.04) and ponto-cerebellar ischemia (χ 2 = 8.09, P = 0.005). During follow-up after SAH, 13 patients (65%) died, after a median survival time of 24 hours (IQR 66.2, range 2-264 hours), with a significant association between proven ponto-cerebellar ischemia and case fatality (χ 2 = 6.24, P = 0.01). The data establish an association between clinical deterioration in patients with VBD, vertebrobasilar ischemia, and subsequent SAH. Antithrombotic treatment after deterioration appears controversial and SAH outcome is frequently fatal. Our data also indicate a short window of 3 days that may allow for evaluating interventional treatment, preferably within randomized trials
Assessment of recent process analytical technology (PAT) trends : a multiauthor review
No full textThis multiauthor review article aims to bring readers up to date with some of the current trends in the field of process analytical technology (PAT) by summarizing each aspect of the subject (sensor development, PAT based process monitoring and control methods) and presenting applications both in industrial laboratories and in manufacture e.g. at GSK, AstraZeneca and Roche. Furthermore, the paper discusses the PAT paradigm from the regulatory science perspective. Given the multidisciplinary nature of PAT, such an endeavour would be almost impossible for a single author, so the concept of a multiauthor review was born. Each section of the multiauthor review has been written by a single expert or group of experts with the aim to report on its own research results. This paper also serves as a comprehensive source of information on PAT topics for the novice reader
