An integrated pharmacokinetic/pharmacogenomic analysis of ABCB1 and SLCO1B1 polymorphisms on edoxaban exposure.

Edoxaban and its low-abundance, active metabolite M4 are substrates of P-glycoprotein (P-gp; MDR1) and organic anion transporter protein 1B1 (OATP1B1), respectively, and pharmacological inhibitors of P-gp and OATP1B1 can affect edoxaban and M4 pharmacokinetics (PK). In this integrated pharmacogenomic analysis, genotype and concentration-time data from 458 healthy volunteers in 14 completed phase 1 studies were pooled to examine the impact on edoxaban PK parameters of allelic variants of ABCB1 (rs1045642: C3435T) and SLCO1B1 (rs4149056: T521C), which encode for P-gp and OATP1B1. Although some pharmacologic inhibitors of P-gp and OATP1B1 increase edoxaban exposure, neither the ABCB1 C3435T nor the SLCO1B1 T521C polymorphism affected edoxaban PK. A slight elevation in M4 exposure was observed among SLCO1B1 C-allele carriers; however, this elevation is unlikely to be clinically significant as plasma M4 concentrations comprise <10% of total edoxaban levels.

International field trials of pyrethroid-treated wood exposed to Coptotermes acinaciformis in Australia and Coptotermes formosanus (Isoptera: Rhinotermitidae) in China and the United States.

Coptotermes Wasmann is one of the most important genera of wood-destroying insect pests, both in its native and introduced countries. Pyrethroids are among the most widely used insecticides in wood preservation around the world. Consequently, they have often been evaluated against different species of Coptotermes. However, because various test methods have been used between countries, comparing results is problematic. These field trials, using a single aboveground method of exposure, assessed a range of retentions of two pyrethroids (bifenthrin and permethrin) in Pinus radiata D. Don sapwood against two species of Coptotermes in three countries to provide directly comparable results. Coptotermes acinaciformis (Froggatt) in Australia consumed the most nontreated wood, followed by Coptotermes formosanus Shiraki in China, then C. formosanus in the United States, although these data were not significantly different. Both termite species demonstrated a dose-response to wood treated with the two pyrethroids; less wood was consumed as retention increased. Overall, C. acinaciformis consumed relatively little of the treated wood. In comparison, C. formosanus consumed 20-90% of the wood treated at the lowest retentions of the pyrethroids evaluated. Results indicated that C. acinaciformis was more sensitive to pyrethroid toxicity/repellency compared with C. formosanus. Factors that may have influenced the results are discussed. However, using a single aboveground method of exposure across three countries, that suited both species of Coptotermes, made it possible to determine unambiguously the actual differences between the species in their tolerances to the two pyrethroid insecticides.

Prevalence, incidence, and persistence of syphilis infection in female sex workers in a Chinese province.

The study's objectives were to investigate the prevalence, incidence, persistence, and associated risk factors of syphilis in female sex workers (FSWs) in Kaiyuan City, Yunnan, China. Three serial cross-sectional surveys were conducted and biological specimens were collected and tested for HIV, sexually transmitted infections, and drug use. The logistic Generalized Estimating Equation regression model was used to identify risk factors for prevalent syphilis. The prevalence of syphilis was 7·5%, 8·4% and 8·8%, respectively, in the three survey periods. Estimated syphilis incidence was 1·07 cases/100 person-years, and the persistence of syphilis per person at 6 months was 90·4%. In multivariate analysis, the factors associated with syphilis were age, lower education level, number of clients in a week, inconsistent condom use with clients, herpes simplex virus type 2 (HSV-2), and Chlamydia trachomatis. Persistent syphilis in this population of FSWs is a serious public health concern.

Abnormal epidermal keratinization in the repeated epilation mutant mouse.

Repeated epilation (Er) is a radiation-induced, autosomal, incomplete dominant mutation in mice which is expressed in heterozygotes but is lethal in the homozygous condition. Many effects of the mutation occur in skin: the epidermis in Er/Er mice is adhesive (oral and nasal orifices fuse, limbs adhere to the body wall), hyperplastic, and fails to undergo terminal differentiation. Skin from fetal +/+, Er/+ and Er/Er mice at ages pre- and postkeratinization examined by light, scanning, and transmission electron microscopy showed marked abnormalities in tissue architecture, differentiation, and cell structure; light and dark basal epidermal cells were separated by wide intercellular spaces, joined by few desmosomes, and contained phagolysomes. The numbers of spinous, granular, and superficial layers were highly variable within any given region and among various regions of the body. In some areas, 2-8 layers of granular cells, containing large or diminutive keratohyalin granules, extended to the epidermal surface; in others, the granular layers were covered by several layers of partially keratinized or nonkeratinized cells. In rare instances, a single or small group of cornified cells was present among the granular layers but was not associated with the epidermal surface. Both the granular and nonkeratinized/partially keratinized upper epidermal layers Er/Er skin gave positive immunofluorescence with antiserum to the histidine-rich, basic protein, filaggrin. Proteins in epidermal extracts from +/+, Er/+ and Er/Er mice were separated and identified by radio- and immunolabeling techniques. The Er/Er extract was missing a 26.5- kdalton protein and had an altered ratio of bands in the keratin region. The 26.5-kdalton band was histidine-rich and cross-reacted with the antiserum to rat filaggrin. Several high molecular weight bands present in both Er/Er and +/+ extracts also reacted with the antiserum. These are presumed to be the precursors of filaggrin and to account for the immunofluorescence om Er/Er epidermis even though the product protein is absent. The morphologic and biochemical data indicated that the genetic defect has a general and profound influence on epidermal differentiation, including alteration of two proteins (filaggrin and keratin) important in normal terminal differentiation, tissue architecture, and cytology. Identification of epidermal abnormalities at early stages of development (prekeratinization) and defective structure of other tissues and gross anatomy suggest that the mutation is responsible for a defect in same regulatory step important in many processes of differentiation and development.

Correction of abnormal matrix formed by cmd/cmd chondrocytes in culture by exogenously added cartilage proteoglycan.

The cartilage matrix deficiency (cmd/cmd) mouse fails to synthesize the core protein of cartilage-characteristic proteoglycan (cartilage PG). Chondrocytes from the cmd/cmd cartilage cultured in vitro produced nodules with greatly reduced extracellular matrix. Immunofluorescence staining revealed that the nodules of mutant cells differed from the normal in lacking cartilage PG and in uneven and reduced deposition of type II collagen. Exogenously added cartilage PG prepared from either normal mouse cartilage or Swarm rat chondrosarcoma to the culture medium was incorporated exclusively into the extracellular matrices of the nodules, with a concurrent correction of the abnormal distribution pattern of type II collagen. The incorporation of cartilage PG into the matrix was disturbed by hyaluronic acid or decasaccharide derived therefrom, suggesting that the incorporation process involves the interaction of added proteoglycan with hyaluronic acid. Both the hyaluronic acid-binding region and the protein-enriched core molecule prepared from rat chondrosarcoma cartilage PG could also be incorporated but, unlike the intact cartilage PG, they were distributed equally in the surrounding zones where fibroblast-like cells predominate. The results indicate that the intact form of cartilage PG is required for specific incorporation into the chondrocyte nodules, and further suggest that cartilage PG plays a regulatory role in the assembly of the matrix macromolecules.

Defects in the cartilaginous growth plates of brachymorphic mice.

Homozygous brachymorphic (bm/bm) mice are characterized by disproportionately short stature. Newborn bm/bm epiphyseal cartilages are shorter than normal although the cells in the different zones of growth are relatively well organized. The extracellular matrix reacts poorly with stains specific for sulfated glycosaminoglycans. The ultrastructural appearance of the cartilage matrix indicates normal collagen fibrils; however, proteoglycan aggregate granules are smaller than normal and are present in reduced numbers, particularly in the columnar and hypertrophic zones of the growth plate. In addition, a prominent network of fine filaments, which are extractable in 4 M guanidine hydrochloride, are present in the bm/bm cartilage matrix. These findings suggest that a defect affecting the proteoglycan component of cartilage occurs in bm/bm mice.

Olfactory sensitivity in humans: genetic versus environmental control.

Olfactory sensitivity to acetic acid, isobutyric acid, and 2-sec-butyl-cyclohexanone was tested in 97 adult male twin pairs to determine the extent to which variation in odor perception was genetically determined. Analysis of the data revealed no evidence for heritability of olfactory sensitivity. However, factors significantly associated with odor perception included cigar, pipe, and cigarette smoking; body fatness; alcohol consumption; and diabetes mellitus.

A New Subspecies of Heliconius hermathena (Nymphalidae: Heliconiinae) from Southern Amazonia.

The present paper describes Heliconius hermathena curua Freitas & Ramos ssp. nov. This subspecies exhibits a non-mimetic phenotype typical of H. hermathena, but is characterized by the merging of the yellow streak over the forewing cubitus with the red postmedian band in the dorsal forewing. The subspecies is known from two localities in the south of Altamira, Pará State, Brazil, where it inhabits an isolated patch of "campina" vegetation more than 600 km from the nearest known H. hermathena populations. Geographic isolation of the population is supported by molecular data; based on the mitochondrial gene COI, all individuals of H. hermathena curuassp. nov. form a monophyletic group and all haplotypes found in it are unique, suggesting that gene flow is not currently on-going. Given the fragile situation of Amazonian white sand forests and the proximity of the population to areas of intensive agriculture, this new subspecies and its habitat deserve attention.

Additions to the known U.S. distribution of Latrodectus geometricus (Araneae: Theridiidae).

The range of the brown widow spider Latrodectus geometricus C. L. Koch includes much of Africa and South and Central America. This medically important spider has been recently introduced to Japan, Indonesia, Papua New Guinea, Australia, Hawaii, and California. After the identification of the brown widow spider in New Orleans, LA, and southern Mississippi, surveys in the southeastern United States were conducted from the fall of 2006 through February 2008. We found populations of brown widow spiders in Georgia, Texas, and multiple localities in southeastern Louisiana and Mississippi. In Mississippi, specimens were collected as far north as a county bordering Tennessee. In New Orleans, the brown widow spider has been commonly collected from various locations where human contact is likely.

Aberrant methylation of the BRCA1 CpG island promoter is associated with decreased BRCA1 mRNA in sporadic breast cancer cells.

BRCA1 mRNA is reduced in sporadic breast cancer cells despite the lack of mutations. Because a CpG island is found at the 5' end of the BRCA1 gene, we hypothesized that the decreased BRCA1 mRNA in sporadic breast cancer was associated with aberrant cytosine methylation of the CpG island. We examined BRCA1 mRNA expression in normal human mammary epithelial cells (HMECs), peripheral blood lymphocytes (PBLs) and six sporadic breast cancer cell lines using RT-PCR. The normal breast cells expressed high levels of BRCA1 mRNA. The sporadic breast cancer cell lines and PBLs expressed lower levels of BRCA1 mRNA ranging from a 3-16-fold decrease compared to the normal breast cells. We identified a 600 bp region of the BRCA1 CpG island that possessed strong promoter activity (approximately 40-fold above control), and determined the cytosine methylation patterns of the 30 CpG sites within this region by sodium bisulfite genomic sequencing. The HMECs, PBLs and five of the sporadic breast cancer cell lines were largely unmethylated. However, one sporadic breast cancer cell line, UACC3199, was > or = 60% methylated at all 30 CpG sites (18 sites were 100% methylated) and was associated with an eightfold decrease in BRCA1 mRNA compared to normal breast cells. These findings suggest that aberrant cytosine methylation of the BRCA1 CpG island promoter may be one mechanism of BRCA1 repression in sporadic breast cancer.

Virus-induced diabetes mellitus. IV. Genetic and environmental factors influencing the development of diabetes after infection with the M variant of encephalomyocarditis virus.

The M variant of encephalomyocarditis virus (EMC) infects pancreatic beta cells and causes the development of a diabetic syndrome in susceptible strains of mice. By examining four F1 crosses of susceptible and resistant strains of mice, we found that the development of diabetes after infection was inherited as a recessive trait. Analysis of the data from the F2 generation indicated that more than one gene was involved in the development of EMC-diabetes. The severity and frequency of abnormal glucose levels in EMC-infected animals was markedly influenced by environmental factors.

Glucokinase regulatory protein may interact with glucokinase in the hepatocyte nucleus.

Glucokinase (GK) plays a central role in the sensing of glucose in pancreatic beta-cells and parenchymal cells of the liver. Glucokinase regulatory protein is a physiological inhibitor of GK in the liver. To understand the role of the interaction of these two proteins in glucose sensing, we carried out a series of experiments to localize the protein in the liver cell. The regulatory protein was found to be present mainly in the nucleus of the cell under a variety of conditions that mimicked the glucose status of the fed and fasted state. GK was localized in the nucleus when the cells were exposed to low glucose concentrations. At higher glucose concentrations or in the presence of low concentrations of fructose, GK translocated to the cytoplasm. The effect of fructose was more robust and rapid than the effect of high glucose concentrations. Furthermore, the effect of fructose and high glucose on the translocation of GK from the nucleus could be partially reversed by glucagon. This unusual localization and behavior suggests a role for GK and its regulatory protein in hepatic energy metabolism that may be broader than glucose phosphorylation.

Heterologous expression and characterization of rat liver glucokinase regulatory protein.

Glucokinase is a critical component of the physiological glucose sensor found in cell types that are responsive to changes in plasma glucose levels. The acute regulation of glucokinase activity has been shown to occur via a regulatory protein found in liver parenchymal cells (Van Schaftingen E, Detheux M, Da Cunha MV. Faseb J 8:414-419, 1994). The action of this protein is modulated by phosphate esters of fructose. In the presence of fructose-6-phosphate, the protein inhibits glucokinase in an allosteric competitive manner, while fructose-1-phosphate reverses this inhibition. A cDNA potentially encoding the rat liver regulatory protein has been cloned, but its identity is uncertain because of the small amounts of soluble protein obtained by expression in bacteria. We report the heterologous expression of the regulatory protein in Escherichia coli and its purification to homogeneity and high specific activity in a single chromatographic step. The properties of this recombinant protein are very similar to those of the liver protein. Direct demonstration of the binding of the recombinant protein to glucokinase has been obtained in vitro using coprecipitation experiments and in vivo, using the yeast two-hybrid system. These studies establish that the protein encoded by the cDNA is identical to the glucokinase regulatory protein and also validate tools with which to carry out structure-function studies on the interaction of the regulatory protein with glucokinase.

Loratadine and terfenadine interaction with nefazodone: Both antihistamines are associated with QTc prolongation.

BACKGROUND AND OBJECTIVE: Nefazodone inhibits CYP3A; therefore coadministration with CYP3A substrates such as terfenadine or loratadine may result in increased exposure to these drugs. A potential pharmacodynamic consequence is electrocardiographic QTc prolongation, which has been associated with torsade de pointes cardiac arrhythmia. Therefore a clinical pharmacokinetic-pharmacodynamic evaluation of this potential interaction was conducted. METHODS: A randomized, double-blind, double-dummy, parallel group, multiple-dose design was used. Healthy men and women who were given doses of 60 mg of terfenadine every 12 hours, 20 mg of loratadine once daily, and 300 mg of nefazodone every 12 hours were studied. Descriptive pharmacokinetics (time to maximum concentration, maximum concentration, and area under the plasma concentration-time curve) were used for the examination of interactions among the respective parent drugs and metabolites. QTc prolongation (mean value over the dosing interval) was the pharmacodynamic parameter measured. Kinetic and dynamic analysis was used for the examination of pooled concentration and QTc data with the use of a linear model. RESULTS: Concomitant nefazodone treatment markedly increased the dose interval area under the plasma concentration-time curve of both terfenadine (mean value, 17.3 +/- 8.5 ng. mL/h versus 97.4 +/- 48.9 ng. mL/h; P <.001) and carboxyterfenadine (mean value, 1.69 +/- 0.48 microg. h/mL versus 2.88 +/- 0.53 microg. h/mL; P <.001) and moderately increased the dose interval area under the plasma concentration-time curve of both loratadine (mean value, 31.5 +/- 27.9 ng. h/mL versus 43.7 +/- 25.9 ng. h/mL; P <.014) and descarboethoxyloratadine (mean value, 73.4 +/- 54.9 ng. h/mL versus 81.9 +/- 26.2 ng. h/mL; P <.002). The mean QTc was unchanged with terfenadine alone; however, it was markedly prolonged with concomitant nefazodone and terfenadine (mean [90% confidence interval] prolongation 42.4 ms [34.2, 50.6 ms]; P <.05). Similarly, the mean QTc was unchanged with loratadine alone; however, it was prolonged with concomitant nefazodone and loratadine (21.6 ms [13.7, 29.4 ms]; P <.05). Nefazodone alone did not change mean QTc. QTc was positively correlated with terfenadine plasma concentration (r (2) = 0.21; P =.0001). Similarly, QTc was positively correlated with loratadine plasma concentration (r (2) = 0.056; P =.0008) but with a flatter slope. There was no relationship between QTc and nefazodone plasma concentration during treatment with nefazodone alone (r (2) = 0.002, not significant). CONCLUSIONS: In healthy men and women, concomitant nefazodone treatment at a therapeutic dose increases exposure to both terfenadine and carboxyterfenadine. This increased exposure is associated with marked QTc prolongation, which is correlated with terfenadine plasma concentration. A similar interaction occurs with loratadine, although it is of lesser magnitude. Concomitant administration of nefazodone with terfenadine may have predisposed individuals to the arrhythmia associated with QTc prolongation, torsade de pointes, when terfenadine was available for clinical use. However, a new finding is that in the context of higher than clinically recommended daily doses (20 mg) of loratadine concomitant administration with a metabolic inhibitor such as nefazodone can also result in QTc prolongation.

Progressive increases in serum catalase activity in advancing human immunodeficiency virus infection.

We found that serum from individuals with Acquired Immunodeficiency Syndrome (AIDS) had more (p less than .05) catalase activity (31.5 +/- 5.2 U/mL) than serum from healthy control subjects (7.3 +/- 0.8 U/mL). Moreover, serum catalase (but not glutathione peroxidase) activity increased progressively with advancing human immunodeficiency virus (HIV) infection (i.e., AIDS greater than symptomatic infection greater than asymptomatic infection greater than controls). Increases in serum catalase activity correlated with increases in serum hydrogen peroxide (H2O2) scavenging ability and reached levels which decreased exogenous H2O2-mediated injury to cultured endothelial cells without altering neutrophil bactericidal activity or mononuclear cell cytotoxicity in vitro. Serum catalase activity correlated with serum lactate dehydrogenase (LDH) activity but did not appear to be a consequence of erythrocyte (RBC) hemolysis since RBC fragility and serum haptoglobin levels were comparable in HIV-infected and control subjects. Increases in serum catalase activity may reflect and/or compensate for systemic glutathione and other antioxidant deficiencies in HIV-infected individuals.

Total homocysteine is not a determinant of arterial pulse wave velocity in young healthy adults.

AIMS: Hyperhomocysteinaemia has been associated with reduced pulse wave velocity (PWV) in patients with end-stage renal disease and in those with hypertension. The aim of this study was to examine the association between total homocysteine (tHcy) concentrations, the biochemical and genetic determinants of tHcy and PWV in healthy young adults. METHODS AND RESULTS: A total of 489 subjects aged 20-25 years participated. A fasting blood sample was taken and PWV measured using a non-invasive optical method. tHcy did not correlate with PWV, whether assessed at the aorto-iliac segment (P = 0.18), the aorto-radial segment (P = 0.39) or the aorto-dorsalis-pedis segment (P = 0.22). When tHcy was classified into normal (<15) and high (> or =15micromol/l), PWV did not differ between the two groups at any segment. PWV did not differ by MTHFR C677T or NOS3 G894T genotype, even when smoking and folate sub-groups were considered. Considering aortic PWV as a dependent variable, stepwise regression analysis showed that the only parameter entering the model for all segments was systolic blood pressure (aorto-iliac, P < 0.001; aorto-radial, P = 0.01; aorto-dorsalis-pedis, P = 0.001). Age, sex, COL1A1 genotype and triglycerides entered the model significantly for two of three segments. CONCLUSION: This study shows that arterial PWV is not associated with tHcy in a healthy young population.

Joining forces for children's health.

From airborne particulatesto pesticide-laden fruit, children probably encounter more pollutants than adults. Because their bodies are rapidly developing, children may react more strongly to these toxins, too. The NIEHS hopes to learn more about how several hazardous agents specifically affect kids. Together, the NIEHS and the EPA are spending $10 million to establish up to six Centers for Children's Environmental Health and Disease Prevention Research. The CDC, a third partner,will later help apply center research to public health.

Global health: what's in it for us?

A new report, America's Vital Interest in Global Health, released in June by the Institute of Medicine's (IOM) Board on International Health, calls for increased U.S. foreign health care spending to fund research and education about diseases of the developing world, a global surveillance system to spot environmental changes and emerging disease conditions, public and private sector partnerships to distribute vaccines and drugs overseas, and a new government body to help coordinate these efforts. The report argues that, in an increasingly global society, the United States can't afford to ignore its neighbors' problems, for economic as well as social reasons.

The syndrome of anosmia with hypogonadotropic hypogonadism: a genetic study of 18 new families and a review.

Among 18 NIH probands with anosmia and hypogonadotropic hypogonadism (AHH), seven had affected relatives and three had consanguineous parents. Both sexes were equally affected and parents were phenotypically normal. Parental age was not increased. Cleft lip and palate occurred in both eugonadal and hypogonadal persons, a previously reported association that may represent variable expression of AHH. Diabetes mellitus, usually insulin-dependent, was frequent in probands and their families. Other common traits included obesity, cryptorchidism, and hearing loss. All probands were chromosomally normal. The frequency of some dermatoglyphic traits of probands differed from normal, but no trait was unique to AHH. Segregation analysis of our proband sibships was consistent with a hypothesis of autosomal-recessive inheritance with variable expression. However, genetic heterogeneity was apparent when previous reports of familial AHH were surveyed. An X-linked or male sex-limited autosomal-dominant form with unilateral renal agenesis, mental retardation, and hypotelorism has been observed. The infrequent reports of direct male-to-male transmission limit characterization of an autosomal-dominant form of AHH. Our phenotypic analysis suggests that the traits of mental retardation, renal anomalies, hypotelorism, diabetes, and hearing loss may help to distinguish various forms of AHH, whereas cryptorchidism, clefts, and obesity appear in several types of families. At present, genetic counseling is dependent upon establishing inheritance pattern after examination for the known associated anomalies.

A methodological review of non-therapeutic intervention trials employing cluster randomization, 1979-1989.

A methodological review is presented of 16 non-therapeutic intervention trials published over the last decade which have randomized intact clusters rather than individuals in treatment groups. Each of the trials was surveyed as to the information supplied on six methodological criteria. Although there is increasing recognition of the methodological issues associated with cluster randomization, many investigators are still not aware of the impact of this design on sample size requirements and analysis considerations. Investigators are urged to publish the cluster-specific event rates observed in their trials as a guide for the planning of future studies.