Radioactive penicillin G production by immobilized fungal vesicles

Summary Radioactive penicillin G production from l-[1-¹⁴C]-valine (1.75 GBq · mmol^-1) by native and by calcium alginate gel immobilized mycelium of Penicillium chrysogenum PQ-96 in a medium for antibiotic production as well as by vesicles isolated from the protoplasts of the same strain in a well-defined reaction mixture was investigated. Specific radioactivity of the penicillin G produced by the native vesicles was 1.45 GBq · mmol^-1 and that of the antibiotic synthesized by the calcium alginate gel immobilized vesicles was 1.48 GBq · mmol^-1. By comparison, the specific radioactivity of penicillin G produced by native mycelium was 0.42 GBq · mmol^-1 and of that synthesized by the immobilized mycelium was 0.96 GBq · mmol^-1. Production of radioactive penicillin G by native and immobilized vesicles in repeated use was also investigated. At the beginning of the production phase, the radioactive penicillin G synthesized by the immobilized vesicles was 25 nmol · mg protein^-1 · h^-1 and decreased after 8 days to a level of 11 nmol · mg protein^-1 · h^-1. The half-life of the immobilized vesicles was 7 days. The native vesicles showed a rapid decrease in radioactive antibiotic production. In comparison, the penicillin G production in a repeated use of immobilized vesicles decreased during 40 days from 140 nmol · mg protein^-1 · h^-1 to 60 nmol · mg protein^-1 · h^-1. The half-life of the immobilized vesicles was 35 days. The native vesicles showed after 4 days a lack of activity of penicillin G production. The stability of immobilized mycelium or vesicles in the process of radioactive penicillin G production is discussed.     

Diseases of civilization,today and tomorrow

Summary The term diseases of civilization that would have represented many scourges of the past, now applies to chronic conditions, still of obscure origin, which have replaced them as dominant health problems of the more industrialized countries. The reasons for their emergence include the decline of major epidemic diseases and associated social troubles, and the various consequences of economic development. Both groups of factors are increasingly relevant to the situation in many developing countries, where the expectation of life has been increasing spectacularly for many years, and where changes in the biological, physical and social environment are in progress. The incidence of cardiovascular diseases, cancer and other diseases proceeds gradually and inexorably, and may be hastened by the interaction of old and new risk factors that happen to coexist in some newer industrialized countries. These include: accumulation of environmental pollution, overcrowding in continually growing cities, increase in cigarette smoking, alcohol and fat consumption, and disintegration of the social infrastructure. The interaction of these factors may result in increased incidence, prevalence and mortality from disease of civilization in the now developing world in a few decades to come.

---

Resumen El término arriba mencionado, que hubiera descrito en el pasado a muchas enfermadades epidémicas, se refiere ahora a estados crónicos, de origen todavía oscuro, que las han reemplazado como principal problema de tipo sanitario en los países más industrializados. El declive de las enfermedades epidémicas de mayor importancia, con todos los problemas sociales que estas generaban, junto con algunas consecuencias del desarrollo económico, se cuentan entre las causas de este cambio. En los países en vías de desarrollo dos factores tiene una importancia determinante en la evolución de este proceso: el espectacular aumento de la esperanza de vida y los cambios en los entornos biológico, físico y social. Como con consecuencia de todo ello la incidencia de enfermedades cardiovasculares, cáncer y otras enfermedades va incrementádose inexorablemente, acelerándose su aparición debido a la interacción entre factores de riesgo viejos con los nuevos, que coexisten en los países de in industrialización reciente, entre los que cabe incluir: la acumulación de polución ambiental, el hacinamiento en ciudades de constante crecimiento, el incremento en el consumo de cigarrillos, alcohol y grasas, y la desintegración de las estructuras sociales tradicionales. En las próximas décadas, la interacción entre todos factores, puede conducir a un aumento en la tasa de mortalidad por enfermedades de la civilización en el hasta ahora denominado mundo en vías de desarrollo.

---

Résumé Le terme de maladies de civilisation, qui pouvait correspondre dans le passé à bien des fléaux; s'applique aujourd'hui à des affections chroniques d'origines encore inconnue qui ont remplacé les anciens fléaux comme problèmes dominants de la santé dans les pays les plus développés. Les raisons de leur émergence comprennent d'une part la disparition des grandes épidémies et d'autres conséquences des vicissitudes sociales, et d'autre part l'interaction de divers sousproduits du développement économique. Ces deux groupes de facteurs concernent un nombre croissant de pays en voie de développement: depuis plusieurs années, la durée de vie moyenne de leurs populations s'est allongée de façon spectaculaire et leur environnement biologique, physique et social est en cours de changement. De ce fait, les maladies cardiovasculaires, le cancer et d'autres affections progressent graduellement et inéluctablement, et cette évolution peut être hâtée par l'interaction des vieux et des nouveaux facteurs de risques qui coexistent chez certains nouveaux venus à la civilisation industrielle. Ces risques comprennent: l'accumulation de la pollution dans l'environnement, la sur-population des mégalopoles qui ne cessent de croître, la consommation accrue de tabac, d'alcool et de graisses, la désintégration de l'infrastructure sociale et bien d'autres facteurs encore. L'accumulation de ces agents agressifs peut conduire à accroître dans les prochaines décennies l'incidence et la prévalence des maladies de civilisation et leur taux de mortalité dans le monde présentemment en cours de développement.

---

---

Invited paper presented at the VII International Conference on the Global Impacts of Applied Microbiology, Helsinki, 12–16.8.1985. Session 4     

Regulation of Membrane Flexibility in Human Erythrocytes.

We have used spin-labels to detect prostaglandin E induced changes in erythrocyte membranes. The observed changes in spin-label resonance spectra can be mimicked in erythrocyte ghosts by loading them with cAMP or cGMP. These changes can also be observed by adding either of these cyclic nucleotides to intact cells. This entry of cyclic nucleotides into intact cells is blocked by an inhibitor of the anion channel. We suggest that the observed changes in paramagnetic resonance spectra are due to changes in lipid "fluidity" that are brought about by changes in the biochemical state of membrane-associated proteins (such as spectrin) and in the direct or indirect biophysical interactions of these proteins with membrane lipids.     

Evaluation of the genetic profile of the Pulawska breed

An assessment was made of the genetic variation of the Pulawska pig through the determination of polymorphism of 6 genes and 14 microsatellite sequences. The examinations covered 52 gilts included in a preservation breeding project. The identification of the alleles at microsatellite loci was performed in an ABI PRISM 310 GENETIC ANALYZER. Gene polymorphism was established by the PCR-RLFP method. On the basis of the variation of 6 genes and 14 microsatellites the mean value of the heterozygosity coefficient was estimated at 0.61, while the value of the corresponding PIC coefficient (polymorphism information content) amounted to 0.55. The probability that the genotypes of two randomly chosen individuals in a population are identical was: 6.95 x 10(-3) (based on gene allele frequency) and 1.23 x 10(-14) (based on microsatellite allele frequency).     

A reverse-hybridization assay for the rapid and simultaneous detection of nine HFE gene mutations

Hereditary hemochromatosis (HH) is a very common autosomal recessive disorder of iron metabolism and frequently associated with mutations in the HFE gene. Molecular genetic testing for HFE mutations is considered valuable for carrier identification, as well as for early diagnosis of the disease, allowing simple treatment by phlebotomy and normal survival of patients. We have developed a reverse-hybridization assay for the routine diagnosis of eight previously described and one novel (E168Q) HFE point mutations. The test is based on multiplex DNA amplification and ready-to-use membrane teststrips, which contain oligonucleotide probes for each wild-type and mutated allele immobilized as an array of parallel lines. The procedure is rapid and accessible to automation on commercially available equipment, and by adding new probes the teststrip can easily be adapted to cover an increasing number of mutations.     

Liposomal quercetin potentiates maxi-K channel openings in smooth muscles and restores its activity after oxidative stress

The effects of quercetin-loaded liposomes (PCL-Q) and their constituents, that is, free quercetin (Q) and ‘empty’ phosphatidylcholine vesicles (PCL), on maxi-K channel activity were studied in single mouse ileal myocytes before and after H₂O₂-induced oxidative stress. Macroscopic Maxi-K channel currents were recorded using whole-cell patch clamp techniques, while single BK_Ca channel currents were recorded in the cell-attached configuration. Bath application of PCL-Q (100?μg/ml of lipid and 3?μg/ml of quercetin) increased single Maxi-K channel activity more than threefold, from 0.010?±?0.003 to 0.034?±?0.004 (n?=?5; p?<?0.05), whereas single-channel conductance increased non-significantly from 138 to 146?pS. In the presence of PCL-Q multiple simultaneous channel openings were observed, with up to eight active channels in the membrane patch. Surprisingly, ‘empty’ PCL (100?μg/ml) also produced some channel activation, although it was less potent compared to PCL-Q, that is, these increased NPo from 0.010?±?0.003 to 0.019?±?0.003 (n?=?5; p?<?0.05) and did not affect single-channel conductance (139?pS). Application of PCL-Q restored macroscopic Maxi-K currents suppressed by H₂O₂-induced oxidative stress in ileal smooth muscle cells. We conclude that PCL-Q can activate Maxi-K channels in ileal myocytes mainly by increasing channel open probability, as well as maintain Maxi-K-mediated whole-cell current under the conditions of oxidative stress. While fusion of the ‘pure’ liposomes with the plasma membrane may indirectly activate Maxi-K channels by altering channel’s phospholipids environment, the additional potentiating action of quercetin may be due to its better bioavailability.     

A new species of Discocyrtanus from Mato Grosso,Brazil (Opiliones: Gonyleptidae) with a key to the species of the genus

Discocyrtanus canjinjim sp. n., belonging to the family Gonyleptidae Sundevall, 1833 is described based on nineteen specimens, eleven adult males and eight adult females, collected in the Vila Bela da Santíssima Trindade, in the State of Mato Grosso, Brazil. This new species represents an endemic component for the harvestmen fauna of Chiquitano Dry Forests terrestrial eco-region, being the most occidental point of distribution of the genus, notably found in the Cerrado and the Atlantic Forest. The new species is characterized by femur IV swollen with the same length of dorsal scutum, trochanter IV with prodorsal distal apophysis as a stout hook not bifurcated, and a unique form of genitalia in the genus. This paper also includes the first identification key to the species of the genus after its revalidation.