Conserved cis-regulatory elements of two odorant-binding protein genes, Obp57d and Obp57e, in Drosophila.

Insect odorant-binding proteins function in the sensing of odors, tastes, and pheromones. Genes encoding two odorant-binding proteins, Obp57d and Obp57e, were identified to be involved in the behavioral adaptation of Drosophila sechellia to its host plant. The two genes are expressed in cells associated with taste sensilla on the legs, and the expression pattern in the legs is conserved among closely related species. To identify the cis-regulatory elements necessary for the expression in the leg sensilla, the promoter sequences of Obp57d and Obp57e were compared among species. Two types of conserved sequence-motifs were found as candidate cis-regulatory elements. Functions of these conserved elements in the promoters of D. melanogaster Obp57d and Obp57e were examined by using a newly constructed vector that combines the advantages of φC31 integrase-based transformation and gypsy transposable-element-derived insulators. By GFP-reporter assay using the new vector, it was confirmed that these conserved elements are necessary for the expression in the legs, working synergistically with each other to affect the expression level. Single-nucleotide substitutions in these elements dramatically changed the promoter activity. These results provide insight into the molecular mechanism for evolution of adaptive behavior via modulation of OBP expression levels.

Evolution of expression patterns of two odorant-binding protein genes, Obp57d and Obp57e, in Drosophila.

Odorant-binding proteins (OBPs) function in the perception of chemical signals together with odorant and taste receptors. Genes encoding OBPs form a large family in insect genomes. In Drosophila, the evolution of OBP gene repertoire has been well studied by comparisons of the whole genome sequences from 12 closely related species. In contrast, their expression patterns are known only in Drosophila melanogaster. Two OBP genes, Obp57d and Obp57e, arose by gene duplication at the early stage of D. melanogaster species group evolution, followed by the divergence of open reading frame (ORF) sequences from each other. While most species in the melanogaster group maintain both Obp57d and Obp57e, some species have lost either gene, suggesting that the birth-and-death process is a dominating pattern of evolution at the Obp57d/e locus. However, it has not been explored whether the expression patterns of these two OBP genes are diverged or conserved among species. Here, we examined the expression patterns of Obp57d and Obp57e in the selected species from the melanogaster group using a combination of reporter analysis, RNA in situ hybridization, and quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis. As previously reported for D. melanogaster, expression in the chemosensilla on the legs was observed in all the species examined. Unlike in D. melnanogaster, however, additional expression in the chemosensilla on the mouthparts was observed in some species including Drosophila pseudoobscura, which maintains an ancestral OBP gene at the Obp57d/e locus. This result shows that, as well as their ORF sequences, the expression patterns of Obp57d and Obp57e have diverged substantially between closely related Drosophila species.

Missense and nonsense mutations of the flavin-containing monooxygenase 3 gene in a Japanese cohort.

We sequenced all exons and exon-intron junctions of the flavin-containing monooxygenase 3 (FMO3) gene from 3 Japanese individuals and their family members, who were case subjects that showed low FMO3 metabolic capacity among a population of self-reported trimethylaminuria Japanese volunteers (n=50). We found three novel single nucleotide polymorphisms (SNPs) (g. 20752 A>G, g. 27400 G>A, and g. 30308 C>T) causing an amino acid substitution and stop codons, Asn114Ser in exon 4, Trp388Stop in exon 7, and Gln470Stop in exon 9, respectively. The Trp388Stop and Gln470Stop also presented together with known SNPs, Val257Met and Glu158Lys, respectively, in the same alleles of the FMO3 gene to form novel haplotypes. These sequences are as follows: 1) SNP, 060825Shimizu004; GENE NAME, FMO3; ACCESSION NUMBER, AL021026; LENGTH, 25 base; 5'-TATCCAGTGTAAA/GTAAACATCCTGA-3'. 2) SNP, 060825Shimizu005; GENE NAME, FMO3; ACCESSION NUMBER, AL021026; LENGTH, 25 base; 5'-CCAGTCCCGCTGG/AGCAGCACAAGTA-3'. 3) SNP, 060825Shimizu006; GENE NAME, FMO3; ACCESSION NUMBER, AL021026; LENGTH, 25 base; 5'-TGTAGTCCCTACC/TAGTTTAGGCTGG-3'.

Pharmacokinetics/pharmacodynamics of acetaminophen analgesia in Japanese patients with chronic pain.

Acetaminophen (APAP) is a popular analgesic. In the present study, we characterized the pharmacokinetics and pharmacodynamics of APAP in the Japanese. Five healthy volunteers were administered 1000 mg of APAP orally. Five patients with chronic pain were administered the optimal oral dose of APAP ranging from 600 to 1000 mg to allow for an adequate analgesic effect. Plasma APAP and APAP metabolite concentrations were measured in the volunteers, plasma APAP concentrations and pain scores using a visual analog scale were measured in the patients with chronic pain. Patient data were fitted to a first-order absorption one-compartment model with delayed effects accounted for by an effect compartment. A sigmoid Emax model was used as the pharmacodynamic model. Acetaminophen-cysteine metabolites, which are conjugates of the toxic metabolite N-acetyl-p-benzoquinone-imine, were detected in the plasma at levels lower than 0.2 microg/ml, but no side effects were observed. The pharmacokinetic and pharmacodynamic parameter (mean+/-S.D.) estimates were as follows: clearance, 18.7+/-4.7 l/h; distribution volume, 30.9+/-6.8 l; absorption rate constant, 2.4+/-1.3 h(-1); rate constant for the elimination of APAP from the effect compartment, 1.3+/-0.5 h(-1); maximum pain relief score, 4.6+/-2.2 units; effect compartment concentration at 50% maximum, 2.0+/-1.2 microg/ml; and sigmoid factor, 1.3+/-0.7. These results suggest that these parameters can be used to determine an effective APAP dosage regimen for Japanese patients with chronic pain.

Cohort study of advanced IgA nephropathy: efficacy and limitations of corticosteroids with tonsillectomy.

BACKGROUND: Elevated serum creatinine is associated with poor outcome in IgA nephropathy (IgAN). The efficacy and limitations of corticosteroids in advanced IgAN (Cr >or=1.5 mg/dl), however, remains controversial. METHODS: We retrospectively investigated 70 patients with advanced IgAN (Cr >or=1.5 mg/dl) classified into three groups according to their treatment regimens, that is, steroid pulse with tonsillectomy, conventional steroid, and supportive therapy. We evaluated the three groups to elucidate predictors for the endpoints ESRF and doubled serum creatinine from baseline. RESULTS: Steroid pulse with tonsillectomy, conventional steroid and supportive therapy were performed in 30, 25 and 15 patients, respectively. During the mean follow-up period of 70.3 (12-137) months, 41.4% of patients reached ESRF (13.3 vs. 56.0 vs. 73.3%, p < 0.001) and 45.7% doubled serum creatinine from baseline (16.7 vs. 64.0 vs. 73.3%, p < 0.001). The incidence of ESRF in the patients treated by steroid pulse with tonsillectomy was significantly lower than the incidences in the patients treated by conventional steroid and supportive therapy at a baseline creatinine level of 1.5-2 mg/dl, but no statistical difference was observed at a level of >2 mg/dl. The Kaplan-Meier estimated probability of renal survival without ESRF was 89.2, 74.1 and 72.2% at 5 years and 82.8, 51.0 and 45.1% at 8 years, respectively (p = 0.017). The predictors for ESRF, identified in a Cox proportional hazards model, were baseline serum creatinine (p < 0.001) and interstitial infiltrate (p = 0.003). Steroid pulse with tonsillectomy also had a protective effect on the risk of reaching ESRF (p = 0.013). By target cross-stratification, the patients with baseline creatinine of 1.5-2 mg/dl who underwent steroid pulse with tonsillectomy showed a better renal survival rate than the others (p < 0.001). CONCLUSION: Steroid pulse therapy combined with tonsillectomy may be more effective than conventional steroid therapy in patients with a baseline creatinine level of

Regression of IgA nephropathy: a repeat biopsy study.

Histological cure of immunoglobulin A (IgA) nephropathy has been reported only rarely in adults. To elucidate the reversibility of established IgA nephropathy, we performed a repeat biopsy study. A second biopsy was performed in 35 patients with IgA nephropathy in whom hematuria, an essential finding of IgA nephropathy, had disappeared (proteinuria also had disappeared in 23 patients) after a treatment protocol involving high doses of methylprednisolone and tonsillectomy. The interval between the first and second biopsy was 18 to 138 months (mean, 77.1 months). Mean serum creatinine level was 1.11 +/- 0.35 (SD) mg/dL (range, 0.6 to 1.9 mg/dL) at the time of the first biopsy and 0.96 +/- 0.24 mg/dL at the time of the second biopsy. Mesangial proliferation was significantly reduced in second-biopsy specimens (mesangial proliferation score: first-biopsy specimens, 2.49 +/- 0.74; second-biopsy specimens, 0.91 +/- 0.89; P < 0.001). Acute inflammatory glomerular lesions, such as endocapillary proliferations, glomerular tuft necrosis, and cellular crescents, were present in 32 patients in first-biopsy specimens, whereas these were no longer present in any of the second-biopsy specimens. Although no significant difference in percentage of globally sclerotic glomeruli was observed between the first and second biopsy specimens, the percentage of segmentally sclerotic glomeruli was significantly lower in second-biopsy specimens (P < 0.001). Interstitial mononuclear cell infiltration was markedly reduced in second-biopsy specimens (P < 0.001). The area of renal cortex affected by interstitial fibrosis and/or edema was significantly reduced in second-biopsy specimens (first-biopsy specimens, 21.4% +/- 20.3%; second-biopsy specimens, 9.6% +/- 11.7%; P < 0.01). The distribution of IgA mesangial deposits had diminished in most patients, and no IgA deposits were seen in second-biopsy specimens from 8 patients. These findings indicate that mesangial proliferation and interstitial changes in IgA nephropathy are reversible to a considerable extent. A histological cure may be obtainable in a considerable proportion of patients, especially if treatment is initiated at a relatively early stage.