Analysis of ENU-induced mutations at the Adh locus in Drosophila melanogaster

N-Ethyl-N-nitrosourea (ENU) was used to induce mutations in the Drosophila melanogaster, alcohol dehydrogenase (Adh) gene. Flies were treated with ENU and mated to homozygous intragenic Adh null mutants; Adh null mutations were selected by exposure of the F1 generation to 1-penten-3-ol. Fourteen Adh null mutations were recovered which included 11 from spermatozoa, 2 from oocytes and 1 from a premeiotic spermatocyte. 2 mutations from spermatozoa and 1 of the mutations from oocytes were multilocus deficiencies which included the Adh locus as determined by complementation tests. The remaining 11 intragenic Adh null mutations were sequenced using the Sanger dideoxy method. One Adh null mutation induced in an oocyte was an AT to TA transversion and the mutation induced in a premeiotic spermatocyte was a GC to AT transition, both of which resulted in a single amino acid substitution. The 11 null mutations induced in spermatozoa were a data set in which both the dose of ENU and the treated germ-cell stage were held constant; therefore, only these 11 mutations were used to calculate the mutation frequency and compare the mutations at the Adh locus with those recovered in other studies. The dose of ENU induced a sex-linked recessive lethal frequency approximately 300 times that of the spontaneous frequency; therefore, these mutations were assumed to have been induced by ENU. 2 of the 11 mutations induced in spermatozoa were multilocus deficiencies and 9 were intragenic mutations. 7 of the 9 intragenic mutations were GC to AT transitions which resulted in 5 single amino acid substitutions, 1 premature translation termination codon, and 1 splice site mutation.(ABSTRACT TRUNCATED AT 400 WORDS)     

Discovery of a potent, selective and orally active canine COX-2 inhibitor, 2-(3-difluoromethyl-5-phenyl-pyrazol-1-yl)-5-methanesulfonyl-pyridine

Structure-activity relationship (SAR) studies of 2-[3-di(and tri)fluoromethyl-5-arylpyrazol-1-yl]-5-methanesulfonylpyridine derivatives for canine COX enzymes are described. This led to the identification of 12a as a lead candidate for further progression. The in vitro and in vivo activity of 12a for the canine COX-2 enzyme as well as its in vivo efficacy and pharmacokinetic properties in dog are highlighted.     

QUESTIONABLE COMPENSATION CLAIMS—Principles of Special Examination

In deciding a disputed claim of disability arising from occupation, physicians should ascertain whether a patient''s medical history has any bearing on the disability; they should attempt psychologic evaluation of the patient as it may reflect on the conditions they observe in physical examination; they should investigate symptoms complained of by the patient rather than accept them as prima facie evidence of disability; and they must have knowledge of the extent to which an injury can cause disability.It is urged that standards of physical ability and disability, as well as of other physical factors which may affect compensation claims, be established by organized research.     

Is Didymosphenia geminata an introduced species in New Zealand? Evidence from trends in water chemistry,and chloroplast DNA

Defining the geographic origins of free‐living aquatic microorganisms can be problematic because many such organisms have ubiquitous distributions, and proving absence from a region is practically impossible. Geographic origins become important if microorganisms have invasive characteristics. The freshwater diatom Didymosphenia geminata is a potentially ubiquitous microorganism for which the recent global expansion of nuisance proliferations has been attributed to environmental change. The changes may include declines in dissolved reactive phosphorus (DRP) to low levels (e.g., <2 mg/m³) and increases in dissolved inorganic nitrogen (DIN) to >10 mg/m³ because both these nutrient conditions are associated with nuisance proliferations of D. geminata. Proliferations of D. geminata have been observed in South Island, New Zealand, since 2004. We aimed to address the ubiquity hypothesis for D. geminata in New Zealand using historical river water nutrient data and new molecular analyses. We used 15 years of data at 77 river sites to assess whether trends in DRP or DIN prior to the spread of D. geminata were consistent with a transition from a rare, undetected, species to a nuisance species. We used new sequences of chloroplast regions to examine the genetic similarity of D. geminata populations from New Zealand and six overseas locations. We found no evidence for declines in DRP concentrations since 1989 that could explain the spread of proliferations since 2004. At some affected sites, lowest DRP occurred before 2004. Trends in DIN also did not indicate enhanced suitability for D. geminata. Lack of diversity in the chloroplast intergenic regions of New Zealand populations and populations from western North America is consistent with recent dispersal to New Zealand. Our analyses did not support the proposal that D. geminata was historically present in New Zealand rivers. These results provide further evidence countering proposals of general ubiquity in freshwater diatoms and indicate that, as assumed in 2004, D. geminata is a recent arrival in New Zealand.     

Contrasting effects of low‐level phosphorus and nitrogen enrichment on growth of the mat‐forming alga Didymosphenia geminata in an oligotrophic river

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Structure and variability of recently inserted Alu family members.

The HS subfamily of Alu sequences is comprised of a group of nearly identical members. Individual subfamily members share 97.7% nucleotide identity with each other and 98.9% nucleotide identity with the HS consensus sequence. Individual subfamily members are on the average 2.8 million years old, and were probably derived from a single source 'master' gene sometime after the human/great ape divergence. The recent Alu family member insertions provide a better image of the structure of Alu retroposons before they have had the opportunity to change significantly. All of the HS subfamily members are flanked by perfect direct repeats as a result of insertion at staggered nicks. The 'master' gene from which the HS subfamily members were derived had an oligo-dA rich tail at least 40 bases long. The 'master' gene is very rich in CpG dinucleotides, but nucleotide substitutions within subfamily members accumulated in a random manner typical for Alu sequence with CpG substitutions occurring 9.2 fold faster than non-CpG substitutions.     

Trigonocephaly and the 11q- syndrome.

A seventh case of deletion of the distal long arm of a chromosome 11 is described. As in other cases with this karyotypic abnormality, trigonocephaly is the most noticeable phenotypic peculiarity. A review of common developmental and dysmorphic features among the seven recognized cases is presented.     

A survey of gastrointestinal parasites of olive baboons (Papio anubis) in human settlement areas of Mole National Park, Ghana

Fecal samples from 55 free-ranging olive baboons (Papio anubis) in Mole National Park, Ghana, were collected 22 June-7 July 2008 and analyzed for gastrointestinal parasites. This is the first survey of baboon gastrointestinal parasites in Ghana and provides baseline data for this area. Ninety-three percent of samples were infected, leaving 7% with no parasites observed. Of those infected, there was a 76% prevalence of strongyles, 53% Strongyloides spp., 11% Abbreviata caucasica , 62% prevalence of Balantidium coli (trophozoites and cysts identified), 4% Entomeba hystolytica/dispar, and 47% unidentified protozoan parasites. Of the strongyle infections, 9% were identified as Oesophagostamum sp. One sample contained an unidentified spirurid nematode that resembled Gongylonema sp. Mole has a mixed forest-savanna habitat, and baboons frequently range into human areas, which makes them subject to parasites from each habitat and multiple sources of exposure. We found a high prevalence of nematode parasites, consistent with a wet or cooler forest environment, or high rates of fecal contamination. The presence of Strongyloides sp., E. hystolitica/dispar, and B. coli suggest potential public health risk from baboons, but molecular identification of these parasites, and documentation of their presence in local human populations, would be necessary to confirm zoonotic transmission.