The sleep disorder canine narcolepsy is caused by a mutation in the hypocretin (orexin) receptor 2 gene

Narcolepsy is a disabling sleep disorder affecting humans and animals. It is characterized by daytime sleepiness, cataplexy, and striking transitions from wakefulness into rapid eye movement (REM) sleep. In this study, we used positional cloning to identify an autosomal recessive mutation responsible for this sleep disorder in a well-established canine model. We have determined that canine narcolepsy is caused by disruption of the hypocretin (orexin) receptor 2 gene (Hcrtr2). This result identifies hypocretins as major sleep-modulating neurotransmitters and opens novel potential therapeutic approaches for narcoleptic patients.

An Arabidopsis gene regulatory network for secondary cell wall synthesis

The plant cell wall is an important factor for determining cell shape, function and response to the environment. Secondary cell walls, such as those found in xylem, are composed of cellulose, hemicelluloses and lignin and account for the bulk of plant biomass. The coordination between transcriptional regulation of synthesis for each polymer is complex and vital to cell function. A regulatory hierarchy of developmental switches has been proposed, although the full complement of regulators remains unknown. Here, we present a protein-DNA network between Arabidopsis transcription factors and secondary cell wall metabolic genes with gene expression regulated by a series of feed-forward loops. This model allowed us to develop and validate new hypotheses about secondary wall gene regulation under abiotic stress. Distinct stresses are able to perturb targeted genes to potentially promote functional adaptation. These interactions will serve as a foundation for understanding the regulation of a complex, integral plant component.

A CLOCK polymorphism associated with human diurnal preference

A single nucleotide polymorphism located in the 3' flanking region of the human CLOCK gene was investigated as a predictor of diurnal preference in a population-based random sample of 410 normal adults. Morningness-eveningness preferences were determined using the 19-item Home-Ostberg questionnaire. Subjects carrying one of the two CLOCK alleles, 3111C, had a significantly lower mean Horne-Ostberg score. The distribution of scores was clearly shifted toward eveningness for these subjects. The score difference was independent of age, sex and ethnic heritage, thus making population stratification effects unlikely to explain this difference. These subjects had a substantial 10- to 44-minute delay in preferred timing for activity or sleep episodes. We suggest that the identified polymorphism or another tightly linked polymorphism within the CLOCK gene or its regulatory elements may be responsible for the finding.

Complex HLA-DR and -DQ interactions confer risk of narcolepsy-cataplexy in three ethnic groups

Human narcolepsy-cataplexy, a sleep disorder associated with a centrally mediated hypocretin (orexin) deficiency, is tightly associated with HLA-DQB1*0602. Few studies have investigated the influence that additional HLA class II alleles have on susceptibility to this disease. In this work, 1,087 control subjects and 420 narcoleptic subjects with cataplexy, from three ethnic groups, were HLA typed, and the effects of HLA-DRB1, -DQA1, and -DQB1 were analyzed. As reported elsewhere, almost all narcoleptic subjects were positive for both HLA-DQA1*0102 and -DQB1*0602. A strong predisposing effect was observed in DQB1*0602 homozygotes, across all ethnic groups. Relative risks for narcolepsy were next calculated for heterozygous DQB1*0602/other HLA class II allelic combinations. Nine HLA class II alleles carried in trans with DQB1*0602 were found to influence disease predisposition. Significantly higher relative risks were observed for heterozygote combinations including DQB1*0301, DQA1*06, DRB1*04, DRB1*08, DRB1*11, and DRB1*12. Three alleles-DQB1*0601, DQB1*0501, and DQA1*01 (non-DQA1*0102)-were found to be protective. The genetic contribution of HLA-DQ to narcolepsy susceptibility was also estimated by use of lambda statistics. Results indicate that complex HLA-DR and -DQ interactions contribute to the genetic predisposition to human narcolepsy but that additional susceptibility loci are also most likely involved. Together with the recent hypocretin discoveries, these findings are consistent with an immunologically mediated destruction of hypocretin-containing cells in human narcolepsy-cataplexy.

Identification of a (CUG)n triplet repeat RNA-binding protein and its expression in myotonic dystrophy

Myotonic dystrophy (DM) is an autosomal dominant neuromuscular disease that is associated with a (CTG)n repeat expansion in the 3'-untranslated region of the myotonin protein kinase (Mt-PK) gene. This study reports the isolation and characterization of a (CUG)n triplet repeat pre-mRNA/mRNA binding protein that may play an important role in DM pathogenesis. Two HeLa cell proteins, CUG-BP1 and CUG-BP2, have been purified based upon their ability to bind specifically to (CUG)8 oligonucleotides in vitro. While CUG-BP1 is the major (CUG)8-binding activity in normal cells, nuclear CUG-BP2 binding activity increases in DM cells. Both CUG-BP1 and CUG-BP2 have been identified as isoforms of a novel heterogeneous nuclear ribonucleoprotein (hnRNP), hNab50. The CUG-BP/hNab50 protein is localized predominantly in the nucleus and is associated with polyadenylated RNAs in vivo. In vitro RNA-binding/photocrosslinking studies demonstrate that CUG-BP/hNab50 binds to RNAs containing the Mt-PK 3'-UTR. We propose that the (CUG)n repeat region in Mt-PK mRNA is a binding site for CUG-BP/hNab50 in vivo, and triplet repeat expansion leads to sequestration of this hnRNP on mutant Mt-PK transcripts.

Uptake of liposomes by cultured mouse bone marrow macrophages: influence of liposome composition and size

A wide range of liposome compositions have previously been examined in vivo for their ability to affect the uptake of liposomes into cells of the reticuloendothelial (RE, mononuclear phagocyte) system (Allen, T.M. and Chonn, A. (1987) FEBS Lett. 223, 42-46; Allen et al. (1989) Biochim. Biophys. Acta 981, 27-35). In this study we have examined the ability of cultured murine bone marrow macrophages to endocytose liposomes of various compositions and have looked for correlations between the in vivo and the in vitro observations. Compounds which substantially decreased RE uptake of liposomes in vivo, such as monosialoganglioside (GM1) and a novel synthetic lipid derivative of polyethyleneglycol (PEG-PE), also greatly decreased liposome uptake by bone marrow macrophages in a concentration-dependent manner. Lipids which increase bilayer rigidity, such as sphingomyelin (SM) and cholesterol (CHOL), decreased both in vivo and in vitro uptake of liposomes. Likewise, positive correlations were observed between the in vivo behavior of liposomes containing phosphatidylserine (PS) or various gangliosides and the ability of these liposomes to be taken up by bone marrow macrophages. Total liposome uptake by macrophages increased with incubation time at 37 degrees C while very little liposome association with the macrophages was observed at 4 degrees C. Liposome uptake increased with liposome concentration and for liposomes composed of egg phosphatidylcholine (PC) uptake plateaued at 40 nmol lipid per mg cell protein. There was an inverse correlation between liposome size of extruded large unilamellar vesicles and their uptake by macrophages.

Photochemical inactivation of viruses and bacteria in platelet concentrates by use of a novel psoralen and long-wavelength ultraviolet light

BACKGROUND

A photochemical treatment process has been developed for the inactivation of viruses and bacteria in platelet concentrates. This process is based on the photochemical reaction of a novel psoralen, S-59, with nucleic acids upon illumination with long-wavelength ultraviolet light (UVA, 320-400 nm).

STUDY DESIGN AND METHODS

High levels of pathogens were added to single-donor platelet concentrates containing 3 to 5 x 10(11) platelets in 300 mL of 35-percent autologous plasma and 65-percent platelet additive solution. After treatment with S-59 (150 microM) and UVA (0-3 J/cm2), the infectivity of each pathogen was measured with established biologic assays. In vitro platelet function after photochemical treatment was evaluated during 7 days of storage by using a panel of 14 assays. The in vivo recovery and life span of photochemically treated platelets were evaluated after 24 hours of storage in a primate transfusion model.

RESULTS

The following levels of pathogen inactivation were achieved: >10(6.7) plaque-forming units (PFU) per mL of cell-free human immunodeficiency virus (HIV), >10(6.6) PFU per mL of cell-associated HIV, >10(6.8) infectious dose (ID50) per mL of duck hepatitis B virus (a model for hepatitis B virus), >10(6.5) PFU per mL of bovine viral diarrhea virus (a model for hepatitis C virus), >10(6.6) colony-forming units of Staphylococcus epidermidis, and >10(5.6) colony-forming units of Klebsiella pneumoniae. Expression of integrated HIV was inhibited by 0.1 microM S-59 and 1 J per cm2 of UVA. In vitro and in vivo platelet function were adequately maintained after antiviral and antibacterial treatment.

CONCLUSION

Photochemical treatment of platelet concentrates offers the potential for reducing transfusion-related viral and bacterial diseases.

Cotranslational biogenesis of NF-kappaB p50 by the 26S proteasome

The NFkappaB1 gene encodes two functionally distinct proteins termed p50 and p105. p50 corresponds to the N terminus of p105 and with p65 (RelA) forms the prototypical NF-kappaB transcription factor complex. In contrast, p105 functions as a Rel-specific inhibitor (IKB) and has been proposed to be the precursor of p50. Our studies now demonstrate that p50 is generated by a unique cotranslational processing event involving the 26S proteasome, whereas cotranslational folding of sequences near the C terminus of p50 abrogates proteasome processing and leads to p105 production. These results indicate that p105 is not the precursor of p50 and reveal a novel mechanism of gene regulation that ensures the balanced production and independent function of the p50 and p105 proteins.

MiR-200b and miR-15b regulate chemotherapy-induced epithelial-mesenchymal transition in human tongue cancer cells by targeting BMI1

Chemotherapy has been reported to induce epithelial-mesenchymal transition (EMT) in tumor cells, which is a critical step in the process of metastasis leading to cancer spreading and treatment failure. However, the underlying mechanisms of chemotherapy-induced EMT remain unclear, and the involvement of microRNAs (miRNA) in this process is poorly understood. To address these questions, we established stable chemotherapy-resistant tongue squamous cell carcinoma (TSCC) cell lines CAL27-res and SCC25-res by exposing the parental CAL27 and SCC25 lines to escalating concentrations of cisplatin for 6 months. CAL27-res and SCC25-res cells displayed mesenchymal features with enhanced invasiveness and motility. MiRNA microarray illustrated that miR-200b and miR-15b were the most significantly downregulated microRNAs in CAL27-res cells. Ectopic expression of miR-200b and miR-15b with miRNA mimics effectively reversed the phenotype of EMT in CAL27-res and SCC25-res cells, and sensitized them to chemotherapy, but inhibition of miR-200b and miR-15b in the sensitive lines with anti-sense oligonucleotides induced EMT and conferred chemoresistance. Retrieving the expression of B lymphoma Mo-MLV insertion region 1 homolog (BMI1), a target for miR-200b and miR-15b, in the presence of the miRNA mimics by transfecting CAL27-res cells with pcDNA3.1-BMI1-carrying mutated seed sequences of miR-200b or miR-15b at its 3'-UTR recapitulated chemotherapy-induced EMT. In vivo, enforced miR-200b or miR-15b expression suppressed metastasis of TSCC xenografts established by CAL27-res cells. Clinically, reduced miR-200b or miR-15b expression was associated with chemotherapeutic resistance in TSCCs and poor patient survival. Our data suggest that reduced expression of miR-200b and miR-15b underscores the mechanisms of chemotherapy-induced EMT in TSCC, and may serve as therapeutic targets to reverse chemotherapy resistance in tongue cancers.

Skin colonization by Staphylococcus aureus in patients with eczema and atopic dermatitis and relevant combined topical therapy: a double-blind multicentre randomized controlled trial

BACKGROUND

Staphylococcus aureus has a peculiar ability to colonize the skin of patients with eczema and atopic dermatitis (AD), and is consistently found in eczematous skin lesions in these patients. A correlation between the severity of the eczema and colonization with S. aureus has been demonstrated, and it has been determined that bacterial colonization is an important factor aggravating skin lesions. Patients colonized with S. aureus have been treated with antibiotics in several open and double-blind placebo-controlled studies, with conflicting results.

OBJECTIVES

To investigate the colonizing features of S. aureus in the lesional and nonlesional skin of patients with eczema and AD in China and to compare the therapeutic effect of mupirocin plus hydrocortisone butyrate with vehicle ointment plus hydrocortisone butyrate.

METHODS

A multicentre, double-blind randomized trial was conducted. Eczema Area and Severity Index (EASI) scores were evaluated before the start of the trial and on the 7th, 14th and 28th day of treatment. Swabs for bacterial isolation were taken from lesional skin before the start of the trial and on the 7th, 14th and 28th day of treatment, and from nonlesional skin only before the start of the trial. A combination topical therapy with mupirocin plus hydrocortisone butyrate ointment was used in the experimental group, with vehicle ointment plus hydrocortisone butyrate ointment as a control.

RESULTS

Of 327 patients enrolled in the study, 208 had eczema and 119 had AD. Bacteria were isolated from 70.2% of lesional and 32.7% of nonlesional skin samples from patients with eczema, of which S. aureus accounted for 47.3% and 27.9%, respectively. Bacteria were isolated from 74.8% of lesional and 34.5% of nonlesional skin samples from patients with AD, of which S. aureus accounted for 79.8% and 80.5%, respectively. The colonization density of S. aureus was markedly higher in lesional than in nonlesional skin, both in patients with eczema and with AD (P < 0.01, P < 0.05), and was positively correlated with lesion severity. Considering the EASI scores before and after treatment and the final effective rate, good therapeutic effects were obtained in both the combination experimental groups and the control groups (P < 0.01), and there were no differences in the global therapeutic effect between the two groups in patients with eczema and with AD (P > 0.05). However, in patients with eczema with a clinical score of > 8 or in patients with AD with a clinical score of > 7, the therapeutic effect in the experimental groups was superior to that in the control groups (P < 0.05) on the 7th day of treatment. There were no differences between the two groups on the 14th and 28th days of treatment (P > 0.05). Following the improvement of symptoms and signs of eczema and AD, the positive rates of bacteria and S. aureus were reduced on the 7th day of treatment.

CONCLUSIONS

This study confirmed that lesional skin of patients with eczema and AD was more frequently colonized with S. aureus than was nonlesional skin. The more severe the eczema, the higher the colonization rate of S. aureus, and S. aureus was also more often present in lesional and nonlesional skin in patients with AD than in those with eczema. Staphylococcus aureus infection is related to the pathogenesis of eczema and AD. An antibiotic-corticosteroid combination and corticosteroid alone both gave good therapeutic effect in eczema and in AD, and both reduced colonization by S. aureus. Early combined topical therapy is beneficial to patients with moderate to severe eczema and AD, and it is unnecessary to use antibiotics at later stages of disease or in mild eczema or AD.

Crystal structures of substrate binding to Bacillus subtilis holo-(acyl carrier protein) synthase reveal a novel trimeric arrangement of molecules resulting in three active sites

BACKGROUND

Holo-(acyl carrier protein) synthase (AcpS), a member of the phosphopantetheinyl transferase superfamily, plays a crucial role in the functional activation of acyl carrier protein (ACP) in the fatty acid biosynthesis pathway. AcpS catalyzes the attachment of the 4'-phosphopantetheinyl moiety of coenzyme A (CoA) to the sidechain of a conserved serine residue on apo-ACP.

RESULTS

We describe here the first crystal structure of a type II ACP from Bacillus subtilis in complex with its activator AcpS at 2.3 A. We also have determined the structures of AcpS alone (at 1.8 A) and AcpS in complex with CoA (at 1.5 A). These structures reveal that AcpS exists as a trimer. A catalytic center is located at each of the solvent-exposed interfaces between AcpS molecules. Site-directed mutagenesis studies confirm the importance of trimer formation in AcpS activity.

CONCLUSIONS

The active site in AcpS is only formed when two AcpS molecules dimerize. The addition of a third molecule allows for the formation of two additional active sites and also permits a large hydrophobic surface from each molecule of AcpS to be buried in the trimer. The mutations Ile5-->Arg, Gln113-->Glu and Gln113-->Arg show that AcpS is inactive when unable to form a trimer. The co-crystal structures of AcpS-CoA and AcpS-ACP allow us to propose a catalytic mechanism for this class of 4'-phosphopantetheinyl transferases.

Ultrasound-assisted extraction of ginseng saponins from ginseng roots and cultured ginseng cells

Ultrasound-assisted extraction was evaluated as a simpler and more effective alternative to conventional extraction methods for the isolation of ginsenosides (saponins) from various types of ginseng. The ginseng samples were extracted with different solvents, under either direct sonication by an ultrasound probe horn or indirect sonication in an ultrasound cleaning bath. The ultrasonic extraction was compared with the conventional method of refluxing boiling solvents in a soxhlet extractor, on the yields of both the total saponin isolated by thin-layer chromatography and the individual ginsenosides by high performance liquid chromatography. It was found that the sonication-assisted extraction of ginseng saponins was about three times faster than the traditional extraction method. The ultrasonic extraction was not only more efficient but also convenient for the recovery and purification of the active ingredients of plant materials. In addition, the sonication-assisted extraction can be carried out at lower temperatures which are favorable for the thermally unstable compounds.

The STAT3 inhibitor NSC 74859 is effective in hepatocellular cancers with disrupted TGF-beta signaling

Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide, with few effective therapeutic options for advanced disease. At least 40% of HCCs are clonal, potentially arising from STAT3+, NANOG+ and OCT3/4+ liver progenitor/stem cell transformation, along with inactivation of transforming growth factor-beta (TGF-beta) signaling. Here we report significantly greater signal transducer and activator of transcription 3 (STAT3) and tyrosine phosphorylated STAT3 in human HCC tissues (P<0.0030 and P<0.0455, respectively) than in human normal liver. Further, in HCC cells with loss of response to TGF-beta, NSC 74859, a STAT3-specific inhibitor, markedly suppresses growth. In contrast, CD133(+) status did not affect the response to STAT3 inhibition: both CD133(+) Huh-7 cells and CD133(-) Huh-7 cells are equally sensitive to NSC 74859 treatment and STAT3 inhibition, with an IC(50) of 100 muM. Thus, the TGF-beta/beta2 spectrin (beta2SP) pathway may reflect a more functional 'stem/progenitor' state than CD133. Furthermore, NSC 74859 treatment of Huh-7 xenografts in nude mice significantly retarded tumor growth, with an effective dose of only 5 mg/kg. Moreover, NSC 74859 inhibited tyrosine phosphorylation of STAT3 in HCC cells in vivo. We conclude that inhibiting interleukin 6 (IL6)/STAT3 in HCCs with inactivation of the TGF-beta/beta2SP pathway is an effective approach in management of HCCs. Thus, IL6/STAT3, a major signaling pathway in HCC stem cell renewal and proliferation, can provide a novel approach to the treatment of specific HCCs.

The dose-effect relationships between torture and psychiatric symptoms in Vietnamese ex-political detainees and a comparison group

The purpose of this study was to determine in Vietnamese ex-political detainees newly arrived into the United States a) the prevalence of torture and psychiatric symptoms and b) the dose-effect relationships between cumulative torture experience and the psychiatric symptoms of posttraumatic stress disorder (PTSD) and major depression. The study population included Vietnamese ex-political detainees (N = 51) and a comparison group (N = 22). All respondents received culturally validated instruments with known psychometric properties including Vietnamese versions of the Hopkins Symptom Checklist-25 and the Harvard Trauma Questionnaire. The ex-political detainees, in contrast to the comparison group, had experienced more torture events (12.2 SD = 4.2 vs. 2.6 SD = 3.1) and had higher rates of PTSD (90% vs. 79%) and depression (49% vs. 15%). Dose-effect relationships between cumulative torture experience and psychiatric symptoms were positive with the PTSD subcategory of "increased arousal" revealing the strongest association. These findings provide evidence that torture is associated with psychiatric morbidity in Vietnamese refugees. The demonstration of significant dose-effect responses supports the hypothesis that torture is a major risk factor in the etiology of major depression and PTSD. The generalizability of these results to other torture survivor groups is unknown. The interaction between torture and other pre- and post-migration risk factors over time in different cultural settings still needs to be examined.

Pheromone-regulated genes required for yeast mating differentiation

Yeast cells mate by an inducible pathway that involves agglutination, mating projection formation, cell fusion, and nuclear fusion. To obtain insight into the mating differentiation of Saccharomyces cerevisiae, we carried out a large-scale transposon tagging screen to identify genes whose expression is regulated by mating pheromone. 91,200 transformants containing random lacZ insertions were screened for beta-galactosidase (beta-gal) expression in the presence and absence of alpha factor, and 189 strains containing pheromone-regulated lacZ insertions were identified. Transposon insertion alleles corresponding to 20 genes that are novel or had not previously been known to be pheromone regulated were examined for effects on the mating process. Mutations in four novel genes, FIG1, FIG2, KAR5/ FIG3, and FIG4 were found to cause mating defects. Three of the proteins encoded by these genes, Fig1p, Fig2p, and Fig4p, are dispensible for cell polarization in uniform concentrations of mating pheromone, but are required for normal cell polarization in mating mixtures, conditions that involve cell-cell communication. Fig1p and Fig2p are also important for cell fusion and conjugation bridge shape, respectively. The fourth protein, Kar5p/Fig3p, is required for nuclear fusion. Fig1p and Fig2p are likely to act at the cell surface as Fig1:: beta-gal and Fig2::beta-gal fusion proteins localize to the periphery of mating cells. Fig4p is a member of a family of eukaryotic proteins that contain a domain homologous to the yeast Sac1p. Our results indicate that a variety of novel genes are expressed specifically during mating differentiation to mediate proper cell morphogenesis, cell fusion, and other steps of the mating process.

Sequence-based association analysis of HLA class I and II alleles in Japanese supports conservation of common haplotypes

Alleles of HLA-A, B, C, DRB1, DQB1, and DPB1 loci were fully determined in 117 healthy Japanese. A*2402, A*3303, A*1101, A*0201, B*4403, B*5201, Cw*0102, Cw*1403, Cw*0304, Cw*0702, Cw*0801, and Cw*1202 showed frequencies of over 10%. Multi-locus haplotype frequencies were estimated by the maximum likelihood method. Strength of association between C and B loci was comparable with that between DRB1 and DQB1 loci. Alleles unidentified by a serological method and having very similar nucleotide sequences (A2: A*0201, A*0206, A*0207, B61: B*4002, B*4006) were carried by different haplotypes. Several frequent five-locus haplotypes were identified including A*3303-Cw*1403-B*4403-DRB1(*)1302-DQB1(*)0604, and A*2402-Cw*1202-B*5201-DRB1(*)1502-DQB1(*)0601. These sequence-based haplotypes corresponded to serology-based common haplotypes which have already been described in Japanese. These findings indicate that common HLA haplotypes consist of particular sets of HLA alleles and that these haplotypes have been conserved through recent human evolution.

A glycine-rich region in NF-kappaB p105 functions as a processing signal for the generation of the p50 subunit

Transcription factor NF-kappaB is generally considered to be a heterodimer with two subunits, p50 and p65. The p50 subunit has been suggested to be generated from its precursor, p105, via the ubiquitin-proteasome pathway. During processing, the C-terminal portion of p105 is rapidly degraded whereas the N-terminal portion (p50) is left intact. We report here that a 23-amino-acid, glycine-rich region (GRR) in p105 functions as a processing signal for the generation of p50. A GRR-dependent endoproteolytic cleavage downstream of the GRR releases p50 from p105, and this cleavage does not require any specific downstream sequences. p50 can be generated from chimeric precursor p105N-GRR-IkappaBalpha, while the C-terminal portion (IkappaBalpha) can also be recovered, suggesting that p105 processing includes two steps: a GRR-dependent endoproteolytic cleavage and the subsequent degradation of the C-terminal portion. We have also demonstrated that the GRR can direct a similar processing event when it is inserted into a protein unrelated to the NF-kappaB family and that it is therefore an independent signal for processing.

Synthesis, chromatographic resolution, and anti-human immunodeficiency virus activity of (+/-)-calanolide A and its enantiomers

The anti-HIV agent (+/-)-calanolide A (1) has been synthesized in a five-step approach starting with phloroglucinol [-->5-->6-->11-->18-->(+/-)-1], which includes Pechmann reaction, Friedel-Crafts acylation, chromenylation with 4,4-dimethoxy-2-methylbutan-2-ol, cyclization, and Luche reduction. Cyclization of chromene 11 to chromanone 18 was achieved by employing either acetaldehyde diethyl acetal or paraldehyde in the presence of trifluoroacetic acid and pyridine or PPTS. Luche reduction of chromanone 18 at lower temperature preferably yielded (+/-)-1. Reduction of chromone 12, synthesized by Kostanecki-Robinson reaction from chromene 11, failed to afford (+/-)-1. The synthetic (+/-)-1 has been chromatographically resolved into its optically active forms, (+)- and (-)-1. The anti-HIV activities for synthetic (+/-)-1, as well as resultant (+)- and (-)-1, have been determined. Only (+)-1 accounted for anti-HIV activity, which was similar to the data reported for the natural product, and (-)-1 was inactive.

Steroidogenic factor-1 (SF-1, Ad4BP, NR5A1) and disorders of testis development

Steroidogenic factor-1 (SF-1) (Ad4BP, NR5A1) is a nuclear receptor that regulates many aspects of adrenal and reproductive development and function. Consequently, deletion of the gene (Nr5a1) encoding Sf-1 in XY mice results in impaired adrenal development, complete testicular dysgenesis with Mullerian structures, and female external genitalia. Initial efforts to identify NR5A1 changes in humans focused on 46,XY individuals with combined adrenogonadal failure and Mullerian structures. Although this combination of clinical features is rare, 2 such patients harboring NR5A1 mutations have been described within the past decade. More recently, however, it has emerged that heterozygous loss of function mutations in NR5A1 can be found relatively frequently in children and adults with 46,XY disorders of sex development (DSD) but with apparently normal adrenal function. The phenotypic spectrum associated with these changes ranges from complete testicular dysgenesis with Mullerian structures, through individuals with mild clitoromegaly or genital ambiguity, to severe penoscrotal hypospadias or even anorchia. Furthermore, a non-synonymous polymorphism in NR5A1 may be associated with micropenis or undescended testes within the population. Taken together, these reports suggest that variable loss of SF-1 function can be associated with a wide range of reproductive phenotypes in humans.

Anaesthetic technique may affect prognosis for ovarian serous adenocarcinoma: a retrospective analysis

BACKGROUND

Animal studies have shown that regional anaesthesia and analgesia may prevent or attenuate the surgical stress response by preserving immune function and result in better long-term outcome. We have tested the hypothesis that patients with ovarian serous adenocarcinoma who had surgery with epidural anaesthesia and analgesia would have better long-term outcome than those who were given general anaesthesia (GA) and i.v. opioid analgesia.

METHODS

A retrospective review of medical records identified 143 patients with ovarian serous adenocarcinoma who underwent surgery between January 1994 and October 2006 at the Sun Yat-sen University Cancer Center. Data in the analysis included age, anaesthesia-analgesia technique, ASA status, blood loss, transfusion, duration of surgery, status of preoperative cancer antigen 125, tumour size, International Federation of Gynecology and Obstetrics stage, histological grade, lymph node status, residual macroscopic tumour, and chemotherapy. Survival analysis was made with the main outcome measure of death.

RESULTS

The 3- and 5-yr overall survival rates were 78% and 61% in the patient group who received epidural anaesthesia and analgesia (Group E, n=106), and 58% and 49% in the patient group who received GA and i.v. opioid analgesia (Group G, n=37), respectively. After adjusting for the other variables, Group G had a hazard ratio of 1.214 (P=0.043) in a multivariable Cox regression model compared with Group E.

CONCLUSIONS

This retrospective analysis suggests that epidural anaesthesia and analgesia for ovarian serous adenocarcinoma surgery may reduce mortality during the initial years of follow-up.

Runx2 overexpression enhances osteoblastic differentiation and mineralization in adipose--derived stem cells in vitro and in vivo

Like bone marrow stromal cells, adipose tissue-derived stem cells (ADSCs) possess multilineage potential, a capacity for self-renewal and long-term viability. To confirm whether ADSCs represent a promising source of cells for gene-enhanced bone tissue-engineering, the osteogenic potential of ADSCs under the control of certain osteoinductive genes has been evaluated. Runx2, a transcription factor at the downstream end of bone morphogenetic protein (BMP) signaling pathways, is essential for osteoblast differentiation and bone formation. In this study we used adenovirus vector to deliver Runx2 to ADSCs and then examined the enhancement of osteogenic activity. Overexpression of Runx2 inhibited adipogenesis, as demonstrated by suppression of LPL and PPARgamma expression at the mRNA level and reduced lipid droplet formation. Moreover, ADSCs transduced with Ad-Runx2 underwent rapid and marked osteoblast differentiation as determined by osteoblastic gene expression, alkaline phosphatase activity and mineral deposition. Additionally, histological examination revealed that implantation of Runx2 modified ADSCs could induce mineral deposition and bone-like tissue formation in vivo. These results confirmed, firstly, the ability of Runx2 to promote osteogenesis and cell differentiation and, secondly, the competence of ADSCs as target cells for bone tissue engineering. Our work demonstrates a potential new approach for bone repair using Runx2-modified ADSCs for bone tissue engineering.

GAKIN, a novel kinesin-like protein associates with the human homologue of the Drosophila discs large tumor suppressor in T lymphocytes

Reorganization of the cortical cytoskeleton is a hallmark of T lymphocyte activation. Upon binding to antigen presenting cells, the T cells rapidly undergo cytoskeletal re-organization thus forming a cap at the cell-cell contact site leading to receptor clustering, protein segregation, and cellular polarization. Previously, we reported cloning of the human lymphocyte homologue of the Drosophila Discs Large tumor suppressor protein (hDlg). Here we show that a novel protein termed GAKIN binds to the guanylate kinase-like domain of hDlg. Affinity protein purification, peptide sequencing, and cloning of GAKIN cDNA from Jurkat J77 lymphocytes identified GAKIN as a novel member of the kinesin superfamily of motor proteins. GAKIN mRNA is ubiquitously expressed, and the predicted amino acid sequence shares significant sequence similarity with the Drosophila kinesin-73 motor protein. GAKIN sequence contains a motor domain at the NH(2) terminus, a central stalk domain, and a putative microtubule-interacting sequence called the CAP-Gly domain at the COOH terminus. Among the MAGUK superfamily of proteins examined, GAKIN binds to the guanylate kinase-like domain of PSD-95 but not of p55. The hDlg and GAKIN are localized mainly in the cytoplasm of resting T lymphocytes, however, upon CD2 receptor cross-linking the hDlg can translocate to the lymphocyte cap. We propose that the GAKIN-hDlg interaction lays the foundation for a general paradigm of coupling MAGUKs to the microtubule-based cytoskeleton, and that this interaction may be functionally important for the intracellular trafficking of MAGUKs and associated protein complexes in vivo.

Genomic amplification of MET with boundaries within fragile site FRA7G and upregulation of MET pathways in esophageal adenocarcinoma

Esophageal adenocarcinoma (EA) is characterized by a poor prognosis making the identification of clinically targetable proteins essential for improving patient outcome. We report the involvement of multiple alterations of the MET pathway in EA development and progression. Microarray analysis of Barrett's metaplasia, dysplasia, and EA revealed overexpression of the MET oncogene in EAs but only those with MET gene amplification. STS-amplification mapping revealed that the boundary of the MET amplicon in these EAs is defined by fragile site FRA7G. We also identified an amplicon at 11p13 that resulted in amplification and overexpression of CD44, a gene involved in MET autophosphorylation upon HGF stimulation. Tissue microarrays with phospho-MET-specific antibodies demonstrated a uniformly high abundance of MET activation in primary EA and cells metastatic to lymph nodes but to a lesser extent in a subset of metaplastic and dysplastic Barrett's samples. Increased expression of multiple genes in the MET pathway associated with invasive growth, for example, many MMPs and osteopontin, also was found in EAs. Treatment of EA-derived cell lines with geldanamycin, an inhibitor for tyrosine kinases including MET receptor kinase, reduced cell migration and induced EA cell apoptosis. The data indicate that upregulation of the MET pathway may contribute to the poor outcome of EA patients and that therapeutic agents targeting this pathway may help improve patient survival.