Product quality research institute evaluation of cascade impactor profiles of pharmaceutical aerosols, part 3: Final report on a statistical procedure for determining equivalence

The purpose of this article is to report final results of the evaluation of a chi-square ratio test proposed by the US Food and Drug Administration (FDA) for demonstrating equivalence of aerodynamic particle size distribution (APSD) profiles of nasal and orally inhaled drug products. A working group of the Product Quality Research Institute previously published results demonstrating some limitations of the proposed test. In an effort to overcome the test's limited discrimination, the group proposed a supplemental test, a population bioequivalence (PBE) test for impactor-sized mass (ISM). In this final report the group compares the chi-square ratio test to the ISM-PBE test and to the combination of both tests. The basis for comparison is a set of 55 realistic scenarios of cascade impactor data, which were evaluated for equivalence by the statistical tests and independently by the group members. In many instances, the combined application of these 2 tests appeared to increase the discriminating ability of the statistical procedure compared with the chi-square ratio test alone. In certain situations the chi-square ratio test alone was sufficient to determine equivalence of APSD profiles, while in other situations neither of the tests alone nor their combination was adequate. This report describes all of these scenarios and results. In the end, the group did not recommend a statistical test for APSD profile equivalence. The group did not investigate other in vitro tests, in vivo issues, or other statistical tests for APSD profile comparisons. The studied tests are not intended for routine quality control of APSD.     

Biofilm building capacity of Salmonella enterica strains from the poultry farm environment

The Biofilm (BF) building capacity of different serotypes of Salmonella enterica derived from the poultry farm environment was investigated. Starting point for the investigation was the question if farm-isolated Salmonella serotypes with high importance for poultry meat and egg production are capable of forming a BF under defined laboratory conditions. Several isolates from different stages of the production cycle were chosen and compared to laboratory grown strains of the same serotype. BF building capacity was analyzed in a 96-well format during a time period of 2?days. Pulse field gel electrophoresis was used to establish a relationship between different isolates. The BF building capacity of a monospecies BF was strongly dependent on the temperature used for incubation. Results indicated further that certain farm isolates were capable of forming BF under laboratory conditions, whereas laboratory grown strains were not. Considerable differences between different field serovars and within one serovar exist. In conclusion, the BF building capacity of poultry-derived isolates is a function of adaptation to their host environment. Thus, the control of BF as a reservoir for Salmonella in the farm environment is of crucial importance for the overall improvement of food safety. Mechanical and substance-based approaches for this control exist in several variations, but overall decontamination success is difficult to achieve and needs to be especially adapted to the farm environment.     

The mutated S1-haplotype in sour cherry has an altered S-haplotype-specific F-box protein gene

Gametophytic self-incompatibility (GSI) is an outcrossing mechanism in flowering plants that is genetically controlled by 2 separate genes located at the highly polymorphic S-locus, termed S-haplotype. This study characterizes a pollen part mutant of the S(1)-haplotype present in sour cherry (Rosaceae, Prunus cerasus L.) that contributes to the loss of GSI. Inheritance of S-haplotypes from reciprocal interspecific crosses between the self-compatible sour cherry cultivar Ujfehértói Fürt?s carrying the mutated S(1)-haplotype (S(1)'S(4)S(d)S(null)) and the self-incompatible sweet cherry (Prunus avium L.) cultivars carrying the wild-type S(1)-haplotype revealed that the mutated S(1)-haplotype confers unilateral incompatibility with a functional pistil component and a nonfunctional pollen component. The altered sour cherry S(1)-haplotype pollen part mutant, termed S(1)', contains a 615-bp Ds-like element within the S(1)-haplotype-specific F-box protein gene (SFB(1)'). This insertion generates a premature in-frame stop codon that would result in a putative truncated SFB(1) containing only 75 of the 375 amino acids present in the wild-type SFB(1). S(1)' along with 2 other previously characterized Prunus S-haplotype mutants, S(f) and S(6m), illustrate that mobile element insertion is an evolutionary force contributing to the breakdown of GSI.     

Subcellular Localization and Functional Analysis of the Arabidopsis GTPase RabE

Membrane trafficking plays a fundamental role in eukaryotic cell biology. Of the numerous known or predicted protein components of the plant cell trafficking system, only a relatively small subset have been characterized with respect to their biological roles in plant growth, development, and response to stresses. In this study, we investigated the subcellular localization and function of an Arabidopsis (Arabidopsis thaliana) small GTPase belonging to the RabE family. RabE proteins are phylogenetically related to well-characterized regulators of polarized vesicle transport from the Golgi apparatus to the plasma membrane in animal and yeast cells. The RabE family of GTPases has also been proposed to be a putative host target of AvrPto, an effector protein produced by the plant pathogen Pseudomonas syringae, based on yeast two-hybrid analysis. We generated transgenic Arabidopsis plants that constitutively expressed one of the five RabE proteins (RabE1d) fused to green fluorescent protein (GFP). GFP-RabE1d and endogenous RabE proteins were found to be associated with the Golgi apparatus and the plasma membrane in Arabidopsis leaf cells. RabE down-regulation, due to cosuppression in transgenic plants, resulted in drastically altered leaf morphology and reduced plant size, providing experimental evidence for an important role of RabE GTPases in regulating plant growth. RabE down-regulation did not affect plant susceptibility to pathogenic P. syringae bacteria; conversely, expression of the constitutively active RabE1d-Q74L enhanced plant defenses, conferring resistance to P. syringae infection.     

Efficacy of a herbal product against Histomonas meleagridis after experimental infection of turkey poults

Histomoniasis (infectious enterohepatitis, blackhead) is caused by the protozoan parasite Histomonas meleagridis (H. meleagridis). After the ban of all prophylactic and therapeutic drugs in the European Union, histomoniasis is increasingly responsible for considerable economic problems to the poultry industry. The aim of this study was to investigate the effect of a herbal product with extracts from cinnamon, garlic, lemon, and rosemary on H. meleagridis in turkey poults in vivo. For this purpose, 60 two-week-old poults were divided into three groups. Group 1 received the herbal product in the feed six days before infection and in water three days before infection, then in feed and drinking water until the end of the experiment. Groups 2 and 3 were left untreated. At week 3 of age, Groups 1 and 2 were infected intracloacally with H. meleagridis. Three weeks after infection the surviving birds were euthanized and examined for pathological lesions. Mortality was 20% in Group 1 and 50% in Group 2. There were no deaths in Group 3. DNA of histomonads was detected in all examined caeca and livers of the dead birds, but was not detected in any examined organ of the surviving birds of all groups. There was no noticeable difference in the lesion scores of the dead birds between the groups. The surviving birds of all groups did not show lesions post mortem. Since all effective prophylactic and therapeutic drugs against histomoniasis were banned in the EU, under given conditions the investigated herbal product seems to be an effective alternative for the reduction of mortality in turkeys caused by histomoniasis.     

Establishment of Ulmus pumila seedlings on steppe slopes of the northern Mongolian mountain taiga

The potential of Siberian elm (Ulmus pumila) to regenerate from seeds was experimentally studied on south-facing slopes in the northern Mongolian mountain taiga. These slopes are covered with a vegetation mosaic of different steppe communities and small, savanna-like, U. pumila open woodlands. The hypothesis is tested that the xeric microclimate and high herbivore densities limit the success of seedling establishment in U. pumila and thereby prevent elm from complete encroachment of the grassland-dominated slopes. Seeds were sown and 2-yr-old seedlings were planted prior to the growing season. The water supply was manipulated by irrigation, as was the feeding pressure by caterpillars with an insecticide. Large herbivores were excluded by fencing. Seeds germinated throughout the summer, but the emerged seedlings did not survive for more than 2 or 3 weeks. Germination rates increased with increasing soil water content and decreasing soil temperatures. Many seeds were consumed by granivores. Most planted 2-yr-old seedlings survived the two growing seasons covered by the study. However, the seedlings suffered from feeding damage by insects (gypsy moth, grasshoppers) and small mammals, from nitrogen deficiency and, to a lesser degree, from drought. The results suggest that high susceptibility of newly emerged seedlings to environmental stresses is a serious bottle neck for U. pumila that prevents them from the formation of closed forests on northern Mongolia's steppe slopes, whereas the probability for seedling survival after this early stage is high.