Organic nanofibers containing insect pheromone disruptants: a novel technical approach to controlled release dispensers with potential for process mechanization.

Beginning fifty years ago, the search for suitable dispensers containing insect pheromones grew with the availability of these synthetic biotechnical tools. Many economic entomologists and application engineers dearly wish they had the "smart, intelligent and ideal dispenser". More or less suitable approximations are available commercially, but none so far meets all demands. Under economic strictures, novel inexpensive systems would be advantageous with release characteristics tailored to the specific life histories of pest insects, the plants considered and the numerous requirements of growers alike. Simultaneously, their field distribution should be mechanizable and be accomplished by one (or very few) application runs. The dispensers should be biodegradable, biocompatible, sustainably applicable, and they should be based on renewable resources. This report presents first results of a novel organic, electrospun nanofiber dispenser with dimensions in the upper nanometer range. Its load of pheromone can be adjusted to be sufficient for 7 weeks of constant disruptive action in vineyards and can be directed against the European Grape Vine Moth Lobesia botrana (Lepidoptera: Tortricidae) which here serves as a readily available model. Mating disruption in L. botrana and the related Eupoecilia ambiguella is a well studied and developed engineering process. Equally, nanofiber production by electrospinning (for a comprehensive review see Greiner and Wendorff, 2007A, B) is well known and already has numerous applications in filtration technology, air conditioning, and medical wound dressing. Our goal was to bring together and successfully mate these (partly incompatible) technologies via technical tricks of a proprietary nature. Even though the lifetime and effectiveness of currently available nanofibers still must be doubled, the rather complicated system of their production and analysis is known well enough to identify the parameters that need future adjustment. Another challenge is the mechanical distribution of the fibers in the vineyards by suitable machinery. Also, in this respect, certain technical leads are available for future development.

Organic electrospun nanofibers as vehicles toward intelligent pheromone dispensers: characterization by laboratory investigations.

Organic nanofibers have a history of technical application in various independent fields, including medical technology, filtration technology, and applications of pharmaceuticals via inhalation into the lungs. Very recently, in a joint effort with polymer chemists, agricultural applications have been added to this list of priorities. The aim is finding novel approaches to insect control. Pheromones, dispensed in a quantifiable way, are being used here in disrupting the mating communication between male and female pest insects, e.g. the European grapevine moth Lobesia botrana (Lepidoptera: Tortricidae), where current dispenser technology does not fully meet the high expectations of growers and environmentalists with respect to longevity of constant release, self decomposition, mechanical distribution, renewability as well as sustainability of resources. The methodology of electrospinning is exhaustively covered by Greiner and Wendorff (2007), with technical details reported by Hellmann et al. (2009), Hein et al. (2011), and Hummel et al. (2010). Wind tunnel studies were run within a tunnel with adjustable laminar flow and 0.5 m/sec air velocity. Mass losses of the electrospun fiber bundles were determined with a sensitive analytical balance 2-3 times per week and recorded as time vs. mass change. CLSA experiments were performed with a self developed glass apparatus (Lindner, 2010) based on various suggestions of previous authors. Microgram quantities of volatile pheromone (E,Z)-7,9-Dodecadienylacetate were absorbed on a filter of rigorously purified charcoal and desorbed by repeated micro extraction with a suitable solvent mixture. Aliquots of the solution were subjected to temperature programmed capillary GLC. Retention times were used for identification, whereas the area covered by the pheromone peak originating from a FID detector signal was integrated and compared with a carefully calibrated standard peak. Since these signals were usually in the low nanogram range, several replications were averaged for statistical improvement. - Thermogravimetric analysis between ambient temperature and 500 degrees C provided a series of degradation curves where the diagram contained information on the evaporation of pheromone alone, polymer fiber alone and pheromone included in the fiber.- Microscopic investigations resulted in pictures of nanofibers from which the overall morphology and the fiber dimensions could be quantified. Organic nanofibers loaded with the grapevine moth pheromone have been well characterized by 5 different lab methods, followed by field bioassays reported elsewhere in these communications volumes (HUMMEL et al., 2011). This comprehensive analytical approach to fiber characterization is new and will be further refined. The federal agency JKI Berlin subjected the pheromone loaded organic fibers to various independent toxicological and ecotoxicological tests and found no adverse side effects.

[Rehabilitation and the Internet]. / Rehabilitation und Internet.

An overview is presented of the technical conditions, approaches, existing Internet services, famous homepages about rehabilitation in the Internet (WWW) as well as other possibilities of obtaining information via the Internet.

Paediatric thrombo-embolism: the influence of non-genetic factors and the role of activated protein C resistance and protein C deficiency.

UNLABELLED: In many children, the pathogenesis of thrombo-embolism remains unexplained. This study examines the role of non-genetic risk factors in 37 children with venous or arterial thrombosis. Included were 17 patients with portal vein thrombosis following umbilical vein catheterisation, 6 with portal vein thrombosis and an uneventful neonatal period, 4 with deep vein thrombosis, 4 with renal vein thrombosis after kidney transplantation, 1 haemodialysis patient with thromboses of arteriovenous shunts, and 5 with arterial thromboses at various sites. In 25 of these 37 patients (68%) exogenic risk factors and particularly vascular manipulations (24/37) were related to the thrombotic event. Resistance to activated protein C was identified in 5 patients and protein C deficiency in 2 (7/37; 19%). This prevalence was significantly higher than that of the control group (14/243; 5.8%; chi 2, P < 0.008). CONCLUSION: Our data show that non-genetic and particular iatrogenic risk factors can often be identified in children with thrombosis, but activated protein C resistance and protein C deficiency are significant genetic risk factors in this age group.

[Equivalence values of the antioxidative capacity in serum of children with chronic renal failure, chronic hemodialysis and kidney transplantation]. / Aquivalenzwerte der antioxidativen Kapazität im Serum chronisch niereninsuffizienter, chronisch hämodialysierter und nierentransplantierter Kinder.

It is reported on the results of measurements of the antitoxydative capacity (AC) in the serum of children suffering from chronic renal failure, during hemodialysis and after kidney Transplantation. The results show in comparison with healthy children (19.95 +/- 5.22 mm, n = 19) that children suffering from chronic renal failure may develop an increased AC (66.18 +/- 29.14 mm, n = 24). In dialyzed children different values are found previous and after hemodialysis (58.11 +/- 9.25 vs. 17 +/- 3.6 mm). Children show after transplantation the highest values (78.9 +/- 26.04 mm, n = 13). If the increase of the AC is a compensatory and regulatory mechanism or the result of accumulation of antioxydative substances should realized in further investigations. The measurements of vitamin-E-supplemented sera may show that an oral application of vitamin E increase the AC in vivo.

[Malondialdehyde concentration in the serum of children with chronic renal failure, chronic hemodialysis and kidney transplantation]. / Malondialdehydkonzentration (MDA) im Serum chronisch niereninsuffizienter, chronisch hämodialysierter und nierentransplantierter Kinder.

The malondialdehyde equivalent (MDE) was measured by the thiobarbiturate method quantitatively in serum of healthy children, children suffering from chronic renal failure and after kidney transplantation. In the reference group (n = 19) a serum concentration of 3.98 +/- 0.84 nmol/ml was found. Elevated MDE serum concentrations were measured in all groups suffering from renal disease: groups with various degree of diminished renal function (7.05 +/- 2.12 nmol/ml; n = 24), children treated by chronic hemodialysis (6.38 +/- 0.98 nmol/ml; previous dialysis and 6.27 +/- 0.63 nmol/ml after dialysis, n = 9) and children after renal transplantation (6.59 +/- 1.14 nmol/ml; n = 13). In the hemodialysis group the MDE concentration was not affected by a single dialysis nor by sixth months dialysis course. A cell-damaging lipid peroxidation in children suffering from renal diseases is reflected by the investigations.

[The hepatocyte of the fetal rat as an in vitro model system for testing the antioxidant activity of biological fluids]. / Der Hepatozyt der fetalen Ratte als in vitro-Modellsystem zur Prüfung antioxidativer Aktivität von biologischen Flüssigkeiten.

In case of hepatocytes of the fetal rat at the end of the gestation (H.) the lipid-peroxidation was determined by measuring the malondialdehyde (MDA) and the vitality by means of the trypan-blue test. The H. with an incubation up to 120 minutes in PBS formed a high spontaneous value of MDA with a simultaneous loss of the cell activity (r = -0.89; p less than 0.05; n = 25). On the conditions of an experimentally generated activation of O2-radical-forming processes (addition of Fe2+/vit. C) concentration-depending increasing of the MDA-formation and trypan-blue reception of the H. were induced (p less than 0.01). The addition of vit. C reduced the MDA-formation and the vitality of the H. The results exclude a direct relation of the two parameters. The MDA-formation of the H. in vitro can be used for testing antioxidative effects of biological fluids.

[The effect of pH, temperature and albumin content on the vitality of fetal rat liver cells during in vitro tests]. / Einfluss von pH, Temperatur und Albumingehalt auf die Vitalität von Leberzellen fetaler Ratten bei in vitro-Versuchen.

The influence of pH, temperature, and albumin content in the incubation medium on the vitality incubated hepatocytes was tested in vitro as well as the effects in the trypan-blue exclusion test. pH changes between 6.8 and 7.4 in the incubation medium have not any influence on the vitality of the hepatocytes or the trypan-blue exclusion test. Reduced vitality results occurred in an initial pH 7.8 in the incubation medium. The vital dye exclusion test is not useful in case of incubation temperature of 4 degrees C, since the results regarding the vitality of the hepatocytes are only apparently better. An addition of human serum albumin is necessary for a good survival of the hepatocytes during the incubation.

[Treatment and metaphylaxis of cystine urolithiasis in children]. / Therapie und Metaphylaxe der Zystinurolithiasis im Kindesalter.

Basic ideas about the pathogenesis of cystinuria and calculi formation are shown in this case report. Aspects of a present and effective cystine stone therapy are discussed after that. We present the therapeutic procedure in two patients with recurrent cystine urinary stone formation who were operated on cystine stones in the past. Our experiences with a combination of chemolitholysis with N-acetyl-cystein through percutaneous nephrostomy and an oral drug therapy with alpha-mercaptopropionyl-glycin are reported. This form of treatment was successful in our two cases. A metaphylactic therapy is necessary to prevent recurrent cystine stone formation.

[The behavior of serum "liver enzyme" activity in children with chronic renal failure, hemodialysis and kidney transplantation]. / Zum Aktivitätsverhalten von "Leberenzymen" im Serum bei chronisch niereninsuffizienten, hämodialysierten und nierentransplantierten Kindern.

Liver enzymes were measured in 24 children with different degrees of renal insufficiency, in 6 children treated by chronic hemodialysis and in 13 children after kidney transplantation. The hemodialyzed and transplanted patients have the highest ALAT activity, independently of the presence of a liver infection. The AP activity in these patient groups were not different from the reference value. The activity of ALAT, GGT and CHE, respectively were most pathologic in the hemodialysis group. The enzyme activities have not been influenced by a single dialysis and a 6-month dialysis course. In uremic and chronic hemodialyzed patients the enzyme combination of ALAT, GGT and CHE has been recommended in the diagnosis and follow-up control of a liver cell damage. In the evaluation of enzyme activities in comparison with reference values of healthy volunteers an enzyme inhibition by the uremic serum should considered.

[Effect of human uremic serum on the survival of fetal rat hepatocytes]. / Einfluss von humanem urämischem Serum auf die Vitalität fetaler Rattenhepatozyten.

Children suffering from chronic renal insufficiency frequently show a liver cell damage. It is not clarified, whether this damage is caused immediately by chronic renal insufficiency. In the model of fetal rat hepatocytes, which were isolated by trypsin digestion, we have investigated the influence of normal and uremic serum on the lactate dehydrogenase release and the staining with trypan blue, respectively. Fetal rat hepatocytes under incubation conditions seems to be a useful model in the investigation of the influence of uremic metabolism on the liver cell. In our liver cell model the uremic serum did not influence the membrane permeability of hepatocytes for macromolecules. However, the viability of hepatocytes was impaired by 23% compared with normal serum. The vitality-reducing factor of the uremic serum is not dialysable.

Recombinant human interleukin 1 alpha: purification and biological characterization.

Interleukin 1 (IL 1) is a polypeptide hormone produced by activated macrophages that affects many different cell types involved in immune and inflammatory responses. The cloning and expression of a murine IL 1 cDNA in Escherichia coli encoding a polypeptide precursor of 270 amino acids has been reported, and expression of the carboxy-terminal 156 amino acids of this precursor in E. coli yields biologically active IL 1. By using the murine IL 1 cDNA as a probe, we have isolated its human homolog from cDNA generated to lipopolysaccharide-stimulated human leukocyte mRNA. Nucleotide sequence analysis of this cDNA predicts a protein of analysis of this cDNA predicts a protein of 271 amino acids (termed IL 1 alpha) which shows congruent to 61% homology to its murine counterpart but only 27% homology to a recently characterized human IL 1 precursor (IL 1 beta). We have expressed the carboxy-terminal 154 amino acids of IL 1 alpha in E. coli, purified this protein to homogeneity, and have compared it with pure recombinant murine IL 1 in several different IL 1 assays based on murine and human cells. Recombinant IL 1 is capable of stimulating T cell and fibroblast proliferation and inducing fibroblast collagenase and prostaglandin production, thus proving that a single molecule has many of the activities previously ascribed to only partially purified IL 1 preparations. Our results indicate that there exists a family of at least two human IL 1 genes (alpha and beta) whose dissimilar protein products have similar biological activities.

Cloning and expression of murine interleukin-1 cDNA in Escherichia coli.

Interleukin-1 (IL-1), a peptide hormone produced by activated macrophages, possesses the ability to modulate the proliferation, maturation and functional activation of a broad spectrum of cell types and may play a major role in the initiation and amplification of immune and inflammatory responses through its action on these diverse cell populations. IL-1 exhibits microheterogeneity in terms of its relative molecular mass (Mr, 13,000-19,000) and charge properties, and although murine IL-1 has been purified and some of its basic structure-function relationships have been elucidated, it has proved difficult to prepare sufficient amounts of IL-1 for direct and detailed sequence and structural studies. Here we report the cloning, sequence analysis and expression of murine IL-1 cDNA in Escherichia coli. The IL-1 cDNA codes for a polypeptide precursor of 270 amino acids. Biologically active IL-1 was produced in E. coli by expressing the carboxy-terminal 156 amino acids of the IL-1 precursor.