Phylogenetic lineages in Pseudocercospora

Pseudocercospora is a large cosmopolitan genus of plant pathogenic fungi that are commonly associated with leaf and fruit spots as well as blights on a wide range of plant hosts. They occur in arid as well as wet environments and in a wide range of climates including cool temperate, sub-tropical and tropical regions. Pseudocercospora is now treated as a genus in its own right, although formerly recognised as either an anamorphic state of Mycosphaerella or having mycosphaerella-like teleomorphs. The aim of this study was to sequence the partial 28S nuclear ribosomal RNA gene of a selected set of isolates to resolve phylogenetic generic limits within the Pseudocercospora complex. From these data, 14 clades are recognised, six of which cluster in Mycosphaerellaceae. Pseudocercospora s. str. represents a distinct clade, sister to Passalora eucalypti, and a clade representing the genera Scolecostigmina, Trochophora and Pallidocercospora gen. nov., taxa formerly accommodated in the Mycosphaerella heimii complex and characterised by smooth, pale brown conidia, as well as the formation of red crystals in agar media. Other clades in Mycosphaerellaceae include Sonderhenia, Microcyclosporella, and Paracercospora. Pseudocercosporella resides in a large clade along with Phloeospora, Miuraea, Cercospora and Septoria. Additional clades represent Dissoconiaceae, Teratosphaeriaceae, Cladosporiaceae, and the genera Xenostigmina, Strelitziana, Cyphellophora and Thedgonia. The genus Phaeomycocentrospora is introduced to accommodate Mycocentrospora cantuariensis, primarily distinguished from Pseudocercospora based on its hyaline hyphae, broad conidiogenous loci and hila. Host specificity was considered for 146 species of Pseudocercospora occurring on 115 host genera from 33 countries. Partial nucleotide sequence data for three gene loci, ITS, EF-1α, and ACT suggest that the majority of these species are host specific. Species identified on the basis of host, symptomatology and general morphology, within the same geographic region, frequently differed phylogenetically, indicating that the application of European and American names to Asian taxa, and vice versa, was often not warranted.

Taxonomic novelties:

New genera - Pallidocercospora Crous, Phaeomycocentrospora Crous, H.D. Shin & U. Braun; New species - Cercospora eucommiae Crous, U. Braun & H.D. Shin, Microcyclospora quercina Crous & Verkley, Pseudocercospora ampelopsis Crous, U. Braun & H.D. Shin, Pseudocercospora cercidicola Crous, U. Braun & C. Nakash., Pseudocercospora crispans G.C. Hunter & Crous, Pseudocercospora crocea Crous, U. Braun, G.C. Hunter & H.D. Shin, Pseudocercospora haiweiensis Crous & X. Zhou, Pseudocercospora humulicola Crous, U. Braun & H.D. Shin, Pseudocercospora marginalis G.C. Hunter, Crous, U. Braun & H.D. Shin, Pseudocercospora ocimi-basilici Crous, M.E. Palm & U. Braun, Pseudocercospora plectranthi G.C. Hunter, Crous, U. Braun & H.D. Shin, Pseudocercospora proteae Crous, Pseudocercospora pseudostigmina-platani Crous, U. Braun & H.D. Shin, Pseudocercospora pyracanthigena Crous, U. Braun & H.D. Shin, Pseudocercospora ravenalicola G.C. Hunter & Crous, Pseudocercospora rhamnellae G.C. Hunter, H.D. Shin, U. Braun & Crous, Pseudocercospora rhododendri-indici Crous, U. Braun & H.D. Shin, Pseudocercospora tibouchinigena Crous & U. Braun, Pseudocercospora xanthocercidis Crous, U. Braun & A. Wood, Pseudocercosporella koreana Crous, U. Braun & H.D. Shin; New combinations - Pallidocercospora acaciigena (Crous & M.J. Wingf.) Crous & M.J. Wingf., Pallidocercospora crystallina (Crous & M.J. Wingf.) Crous & M.J. Wingf., Pallidocercospora heimii (Crous) Crous, Pallidocercospora heimioides (Crous & M.J. Wingf.) Crous & M.J. Wingf., Pallidocercospora holualoana (Crous, Joanne E. Taylor & M.E. Palm) Crous, Pallidocercospora konae (Crous, Joanne E. Taylor & M.E. Palm) Crous, Pallidoocercospora irregulariramosa (Crous & M.J. Wingf.) Crous & M.J. Wingf., Phaeomycocentrospora cantuariensis (E.S. Salmon & Wormald) Crous, H.D. Shin & U. Braun, Pseudocercospora hakeae (U. Braun & Crous) U. Braun & Crous, Pseudocercospora leucadendri (Cooke) U. Braun & Crous, Pseudocercospora snelliana (Reichert) U. Braun, H.D. Shin, C. Nakash. & Crous, Pseudocercosporella chaenomelis (Y. Suto) C. Nakash., Crous, U. Braun & H.D. Shin; Typifications: Epitypifications - Pseudocercospora angolensis (T. Carvalho & O. Mendes) Crous & U. Braun, Pseudocercospora araliae (Henn.) Deighton, Pseudocercospora cercidis-chinensis H.D. Shin & U. Braun, Pseudocercospora corylopsidis (Togashi & Katsuki) C. Nakash. & Tak. Kobay., Pseudocercospora dovyalidis (Chupp & Doidge) Deighton, Pseudocercospora fukuokaensis (Chupp) X.J. Liu & Y.L. Guo, Pseudocercospora humuli (Hori) Y.L. Guo & X.J. Liu, Pseudocercospora kiggelariae (Syd.) Crous & U. Braun, Pseudocercospora lyoniae (Katsuki & Tak. Kobay.) Deighton, Pseudocercospora lythri H.D. Shin & U. Braun, Pseudocercospora sambucigena U. Braun, Crous & K. Schub., Pseudocercospora stephanandrae (Tak. Kobay. & H. Horie) C. Nakash. & Tak. Kobay., Pseudocercospora viburnigena U. Braun & Crous, Pseudocercosporella chaenomelis (Y. Suto) C. Nakash., Crous, U. Braun & H.D. Shin, Xenostigmina zilleri (A. Funk) Crous; Lectotypification - Pseudocercospora ocimicola (Petr. & Cif.) Deighton; Neotypifications - Pseudocercospora kiggelariae (Syd.) Crous & U. Braun, Pseudocercospora lonicericola (W. Yamam.) Deighton, Pseudocercospora zelkovae (Hori) X.J. Liu & Y.L. Guo.Key words: Capnodiales, Cercospora, cercosporoid, Mycosphaerella, Mycosphaerellaceae, Paracercospora, Pseudocercosporella, Multi-Locus Sequence Typing (MLST), systematics     

Pharmacokinetics and pharmacodynamics of stereoisomeric drugs with particular reference to bioequivalence determination

Drugs containing one or more chiral centres exist in stereoisomeric molecular forms. Most commonly, drugs containing a single asymmetric carbon atom exist in two enantiomeric forms, designated as eutomer (the more potent) and distomer (the less potent). As well as differences in potency and other pharmacodynamic properties, most members of enantiomeric pairs commonly differ also in their pharmacokinetic profiles. This article reviews factors underlying differences in pharmacological properties of enantiomers. The relevance of such differences for studies designed to evaluate the bioequivalence of products containing chiral drugs is also reviewed.     

Thermoregulatory capacity and muscle membrane integrity are compromised in broilers compared with layers at the same age or body weight

1. The effects of acute heat stress (2 h at 32 degrees C and 75% RH) on body temperature and indices of respiratory thermoregulation and skeletal muscle function were examined in two divergently selected male grandparent lines of broiler and layer-type chickens at two ages (35 and 63 d), or at a similar body weight (approximately 2.2 kg). 2. The two chicken lines exhibited markedly different baseline blood acid-base and skeletal muscle characteristics. At the same age or live weight, birds from the broiler line had significantly higher venous blood carbon dioxide tensions associated with lower blood pH. Plasma creatine kinase (CK) activities reflecting muscle membrane damage were also greatly elevated in the broiler line. 3. Exposure to acute heat stress caused an increase in deep body temperature, panting-induced acid-base disturbances and elevated plasma CK activity in both lines of chicken, an effect that increased with age. The extent of disturbances in acid-base regulation and heat-stress-induced myopathy were more pronounced in the broiler than the layer line at the same age or similar live weights. 4. It is suggested that genetic selection for high muscle growth in broiler lines has compromised their capacity to respond to an acute thermal challenge, leading to detrimental consequences for muscle function. This reduction in heat tolerance may have important implications for bird welfare and subsequent meat quality.     

Interspecies allometric scaling. Part I: prediction of clearance in large animals

Interspecies scaling is a useful tool for the prediction of pharmacokinetic parameters from animals to humans, and it is often used for estimating a first-time in human dose. The knowledge of pharmacokinetics in veterinary species is important for dosage selection, particularly in the treatment of large zoo animal species, such as elephants, giant cats and camels, for which pharmacokinetic data are scant. Therefore, the accuracy in clearance predictions in large animal species, with and without the use of correction factors (rule of exponents), and the impact of species selection in the prediction of clearance in large animal species was examined. Based upon this analysis, it was determined that there is a much larger risk of inaccuracies in the clearance estimates in large animal species when compared with that observed for humans. Unlike in humans, for large animal species, correction factors could not be applied because there was no trend between the exponents of simple allometry and the appropriate correction factor for improving our predictions. Nevertheless, we did see an indication that the exponents of simple allometry may alert us as to when the predicted clearance in the large animal may be underestimated or overpredicted. For example, if a large animal is included in the scaling, the predicted clearance in a large animal should be considered overestimated if the exponent of simple allometry is >1.3. Despite the potential for extrapolation error, the reality is that allometric scaling is needed across many veterinary practice situations, and therefore will be used. For this reason, it is important to consider mechanisms for reducing the risk of extrapolation errors that can seriously affect target animal safety, therapeutic response, or the accuracy of withdrawal time predictions.     

Immunity to chlamydial infections in mice—II. A quantitative study of respiratory challenge

Comparative, quantitative disease responses to intranasal chlamydial infection in susceptible mice and others vaccinated either intraperitoneally or intranasally three weeks previously are recorded. Resistance to challenge was confirmed in both vaccinated groups being manifest by reduced mortality, inhibited growth and survival of the organism, and increased lung macrophage response     

The effects of transfer factor, parasitic antigen and precipitated immunoglobulin treatments in lambs infected with Haemonchus contortus

Significant reductions in adult worm burdens in lambs less than six months old infected with 5000 third stage Haemonchus contortus larvae were achieved following the combination of a single transfer factor treatment with multiple parenteral treatments of adult parasitic antigen and precipitated immunoglobulin. Specific cellular responses in the abomasa associated with individual treatments were discernible in all the experimental groups and quantitative differences in these responses reflected the varying treatment levels and treatment combinations. The reactions associated with transfer factor were similar to immediate type hypersensitivity responses and their role as possible effector mechanisms in correcting partial immune incompetency in lambs is discussed.