Leaf Beetles of the Cayman Islands (Coleoptera: Chrysomelidae)

Data are presented for 29 chrysomelid species (Coleoptera: Chrysomelidae) occurring in the Cayman Islands, West Indies, 26 of these not having been reported from these islands previously. Altica occidentalis Suffrian is removed from the genus Lysathia Bechyné and reinstated in Altica Geoffroy. Chaetocnema perplexa Blake is synonymized with Chaetocnema confinis Crotch, new synonymy. Omophoita cyanipennis octomaculata (Crotch) is synonymized with Omophoita cyanipennis (Fabricius), new synonymy. The following nine species are named and described: Apraea luciae, Apraea priscilae, Cryptocephalus catharinae, Cryptocephalus kirki, Cryptocephalus paulotigrinus, Longitarsus alisonae, Megistops adiae, Nyctiplanctus bifasciatus, Syphrea thurstonae, all are new species. Taxonomic notes and a key to species, as well as information on plant associations and extralimital distribution, are also provided

Penurunan Viabilitas Benih Padi (Oryza Sativa L.) melalui Beberapa Metode Pengusangan Cepat

Availability of seed lots with different viabilities is very important as the material for invigoration studies. Acceleratedor rapid aging methods is expected to serve seeds with different viabilities for those studies. The objective of this study was toobtain efficient seeds rapid aging method of rice seeds. The study consisted of three experiments i.e. rapid aging with ethanolgas, soaking seed in liquid ethanol (96%) and exposing seeds to 41 oC temperature and ± 100% relative humidity. Eachexperiment was arranged in a randomized block design with single factor that was length of aging with three replications.There were eight rice varieties used in this study, i. e. three varieties of upland rice, two verieties of lowland rice, and threevarieties of swamp rice. The results showed that the physical aging method could not produce reliable data due to fungusinfection on the treated seed. It was found that generally 60% and 50% viabilities of rice seed could be obtain by ethanol gastreatment for 4.9 and 5.3 hours, as well as by liquid ethanol for 4.0 and 4.4 minutes, respectively. Rapid aging method withliquid ethanol was the fastest and simplest method for decreasing seed viability of rice

Batch and fed-batch cultures of E. coli TB1 at different oxygen transfer rates: Effect of stirring and oxigen partial pressures on cell growth and cytochrome b5 production

Batch cultures of E. coli TB1/pUC13 were carried out at different oxygen transfer rates (OTR) enhanced by the increase of stirring rate and by the increase of air total pressure of the bioreactor. These two variables showed to have little effect on cell growth but a negative effect on cytochrome b5 (recombinant protein) production. However, this effect was more significant of high stirring rates than for values of pressure up to 0.4 MPa. The effects of stirring and pressure were also investigated for fed-batch mode operation. In this type of cell cultivation high cell densities are reached, thus a high capacity of oxygen supply of the system is required. To compare the two ways of improving OTR, cell behaviour was followed in two bioreactors at different operational conditions giving the same maximum OTR value. The first one operated at a high stirring rate (500 rpm) and at atmospheric pressure (0.1 MPa) and the other one at high air pressure (0.48 MPa) and low stirring rate. The increased pressure seemed to be a better way of ensuring an adequate oxygen supply to a culture of E. coli TB1 cells than an increased stirring rate. For the high pressure experiment a higher cellular density was reached, as well as a higher cyt.b5 expression which led to a 4-fold increase in final productivity. These experiments showed that bioreactor pressurization can be successfully used as a means of enhancing oxygen mass transfer to shear sensitive cell cultures.Fundação para a Ciência e a Tecnologia (FCT) – PRAXIS XXI

Sonographic and Computed tomographic demonstration of hepatic hydatid cyst communicating with the biliary tree

A 30 years old male patient presented to the emergency room with a three day history of right upper quadrant pain and jaundice

Hepatic arterioportal fistula: Doppler and Ultrasound findings

A 69 years old female patient presented to our Radiology department to control a hepatic cyst that have been drained because of its great dimensions

Effects of hyperbaric air on the Saccharomyces cerevisae morphology and viability

Fed-batch cultivation of Saccharomyces cerevisae is the dominating technique in high cell density cultures of processes such as the production of Baker's yeast [l] and recombinant proteins [2]. Due to the high oxygen demand of these cultures, the oxygen supply to the culture is an important and difficult task. The use of hyperbaric air, e.g., air at increased pressure, for oxygen mass transfer improvement has been proved to be applicable to several microbial strains [3,4]. In this study, the effects of hyperbaric air up to 1.5 MPa on the viability and morphology of S. cerevisiae cells grown in fed-batch cultures were investigated. Fed-batch experiments were performed in a stainless steel stirred tank reactor. Exponential feeding at dilution rates up to 0.1 h-1 was used, in order to ensure full respiratory metabolism. The ethanol production due to oxygen _limitation at atmospheric pressure was reduced by the bioreactor pressurization up to 1.0 MPa. No differences on the fraction of viable cells, size of the cells and genealogical age were observed in this range of total pressure. Moreover, best results were obtained for experiments where pressure was increased gradually throughout time. This observation indicates the existence of an adaptation period of the cells to hyperbaric conditions. However, a strong inhibition of cell activity was observed for the operation at 1.5 MPa total air pressure. This effect was due to the increase on the oxygen partial pressure because similar cell behaviour was found using pure oxygen at the same partial pressure (0.32 MPa). Oxygen toxicity resulted in a drastic decrease of cell viability, inhibition of ATP synthesis and morphologic changes, mainly, cell size decrease

Response of the thermophile Thermus sp. RQ-1 to hyperbaric air in batch and fed-batch cultivation

The effects of increased air pressure in a cul- ture of the thermophilic microorganism Thermus sp. RQ-1 were investigated. Cell growth dependence on oxygen supply was investigated in a fermenter at atmo- spheric pressure. Total oxygen depletion from the me- dium for low values of kLa was observed during the exponential growth phase. It was possible with this strain to enhance the oxygen transfer rate by increasing the air pressure. Cell productivity was improved by pressurisation up to 0.56 MPa for batch cultivation; and an induction of the antioxidant enzymes, superoxide dismutase and catalase, was observed with the rise in pressure. Cell pre-cultivation under pressurised condi- tions conferred to the cells more resistance to an exposure to hydrogen peroxide and more sensitivity to paraquat (methyl viologen). The usefulness of bioreactor pressurisation on the cultivation of Thermus sp. RQ-1 was demonstrated for fed-batch operation, with the at- tainment of higher cell densities. A two-fold increase in cell mass productivity was obtained by the use of hyperbaric air (0.5 MPa). With the pressurisation of the head-space in the reactor, it was also possible to elimi- nate the loss of liquid by evaporation, which amounted to more than 10% at 70 °C and atmospheric pressure.Fundação para a Ciência e a Tecnologia (FCT) – PRAXIS XXI - project 2/2.1/BIO/20/9

Morphological and physiological changes in Saccharomyces cerevisiae by oxidative stress from hyperbaric air

Increase in air or oxygen pressure in microbial cell cultures can cause oxidative stress and consequently affect cell physiology and morphology. The behaviour of Saccharomyces cerevisiae grown under hyperbaric atmospheres of air and pure oxygen was studied. A limit of 1.0 MPa for the air pressure increase (i.e. 0.21 MPa of oxygen partial pressure) in a fed-batch culture of S. cerevisiae was established. Values of 1.5 MPa air pressure and 0.32 MPa pure oxygen pressure strongly inhibited the metabolic activity and the viability of the cells. Also, morphological changes were observed, especially cell-size distribution and the genealogical age profile. Pressure caused cell compression and an increase in number of aged cells. These effects were attributed to oxygen toxicity since similar results were obtained using air or oxygen, if oxygen partial pressure was equal to or higher than 0.32 MPa. The activity of the antioxidant enzymes, catalase and superoxide dismutase (SOD) (cytosolic and mitochondrial isoformes) indicated that the enzymes have different roles in oxidative stress cell protection, depending on other factors that affect the cell physiological state