Investigating the genetic and environmental structure of Cloninger's personality dimensions in adolescence.

In this study we examined the genetic and environmental structure of four dimensions from Cloninger's personality system: novelty-seeking (NS), harm-avoidance (HA), reward-dependence (RD), and persistence (PS). Although adult twin studies suggest that these personality dimensions are moderately heritable, this is the first twin study of Cloninger's personality dimensions in adolescence--a period marked by significant physiological and social changes. Study participants included 1851 adolescent twins between the ages of 11 and 18 years; 878 complete twin pairs and 95 singleton-responding twins. Subjects were participants in two community-based samples of twins residing in the state of Colorado. Results indicated that cross-sectional mean levels for NS, HA and RD tended to show modest increases across the adolescent years, while PS showed modest mean decreases. Consistent sex differences in means were found only for RD. Univariate biometrical twin models were used to decompose trait variance into genetic and environmental sources. Results indicated that for NS, HA and RD additive genetic influences and unique environmental effects were sufficient to explain the data. PS, however, could be explained by unique and common environmental effects only, with different patterns of common environmental effects for males and females. We found moderate heritability estimates for NS, HA and RD ranging from .28 to .36--with no evidence for sex-limitation in those influences.     

Polymer-assisted solution-phase (PASP) parallel synthesis of an alpha-ketothiazole library as tissue factor VIIa inhibitors

A solution-phase synthesis of an alpha-ketothiazole library of the general form D-Phe-L-AA-L-Arg-alpha-ketothiazole is described. The five-step synthesis is accomplished using a combination of polymeric reagents and polymer-assisted solution-phase purification protocols, including reactant-sequestering resins, reagent-sequestering resins, and tagged reagents. The multi-step synthesis affords the desired alpha-ketothiazole products in excellent purities and yields. A variety of L-amino acid inputs were used to probe the S2 pocket of the tissue factor (TF) VIIa enzyme to influence both potency and selectivity. An X-ray crystal structure of compound 10e bound to the TF/VIIa complex was obtained that explains the observed selectivity. The alpha-ketothiazoles were found to be potent, reversible-covalent inhibitors of tissue factor VIIa, with some analogues demonstrating selectivity versus thrombin.     

Testosterone and prolactin are associated with emotional responses to infant cries in new fathers

To determine the responsiveness of new fathers and non-fathers toward infant cues, we exposed fathers and non-fathers to infant cries and to control stimuli and we measured affective, heart-rate, and endocrine responses, including salivary testosterone and cortisol and plasma prolactin concentrations prior to and after cry presentations. We found that (1) fathers hearing the cry stimuli felt more sympathetic and more alert compared to groups who did not hear the cries or to non-fathers who heard the cries; (2) fathers and non-fathers with lower testosterone levels had higher sympathy and/or need to respond to the infant cries than fathers with higher testosterone levels; (3) fathers with higher, as opposed to lower, prolactin levels were also more alert and more positive in response to the cries; (4) fathers hearing the cry stimuli showed greater percentage increase in testosterone than fathers not hearing the cry stimuli; (5) experienced fathers hearing the cries showed a greater percentage increase in prolactin levels compared to first-time fathers or to any group of fathers hearing control stimuli; finally, (6) partial correlations with parity and experience entered as a covariates indicated that both experience and testosterone contributed to the variance in fathers' affective responses to infant cries. Taken together, these results indicate that, as with a number of other biparental species, human fathers are more responsive to infant cues than are non-fathers and fathers' responses to infant cues are related to both hormones and to caregiving experience.     

Evolution of unbalanced gain of distal chromosome 2p in neuroblastoma

Neuroblastoma, one of the most common tumors of childhood, presents at diagnosis with a vast number of recurrent chromosomal imbalances that include hyperdiploidy for whole chromosomes, partial loss of 1p, 3p, 4p, 11q, 14q, partial gain of 1q, 7q, 17q and amplification of MYCN. These abnormalities are nonrandomly distributed in neuroblastoma as loss of 3p and 11q rarely occur in MYCN amplified neuroblastomas. Here, we report on a patient who had a non-MYCN amplified 3p-/11q- neuroblastoma at diagnosis who subsequently developed a high level of MYCN amplification in bone marrow metastases 41 months after induction of complete remission. The tumor at diagnosis had low level unbalanced gain of distal 2p. In order to assess the frequency of low level gain of distal 2p in neuroblastoma, we examined the comparative genomic hybridization results from 60 neuroblastomas. Among non-MYCN amplified neuroblastomas, 8/45 (18%) had low level gain of distal 2p. Low level gain for a segment of 2p (i.e. a region larger than the 2p23-->p24 undergoing amplification) was also detected in five of the 15 tumors that had high level MYCN amplification. The possibility that low level gain of distal 2p is a risk factor for high level MYCN amplification is discussed.     

Cloning and characterization of sialidases with 2-6' and 2-3' sialyl lactose specificity from Pasteurella multocida

Pasteurella multocida is a mucosal pathogen that colonizes the respiratory system of susceptible hosts. Most isolates of P. multocida produce sialidase activity, which may contribute to colonization of the respiratory tract or the production of lesions in an active infection. We have cloned and sequenced a sialidase gene, nanH, from a fowl cholera isolate of P. multocida. Sequence analysis of NanH revealed that it exhibited significant amino acid sequence homology with many microbial sialidases. Insertional inactivation of nanH resulted in a mutant strain that was not deficient in sialidase production. However, this mutant exhibited reduced enzyme activity and growth rate on 2-3' sialyl lactose compared to the wild type. Subsequently, we demonstrated the presence of two sialidases by cloning another sialidase gene that differed from nanH in DNA sequence and substrate specificity. NanB demonstrated activity on both 2-3' and 2-6' sialyl lactose, while NanH demonstrated activity only on 2-3' sialyl lactose. Neither enzyme liberated sialic acid from colominic acid (2-8' sialyl lactose). Recombinant E. coli containing the sialidase genes were able to utilize several sialoconjugants when they were provided as sole carbon sources in minimal medium. These data suggest that sialidases have a nutritional function and may contribute to the ability of P. multocida to colonize and persist on vertebrate mucosal surfaces.     

CASP8 SNP D302H (rs1045485) Is Associated with Worse Survival in MYCN-Amplified Neuroblastoma Patients

Background

Neuroblastoma is a pediatric cancer that exhibits a wide clinical spectrum ranging from spontaneous regression in low-risk patients to fatal disease in high-risk patients. The identification of single nucleotide polymorphisms (SNPs) may help explain the heterogeneity of neuroblastoma and assist in identifying patients at higher risk for poor survival. SNPs in the TP53 pathway are of special importance, as several studies have reported associations between TP53 pathway SNPs and cancer. Of note, less than 2% of neuroblastoma tumors have a TP53 mutation at diagnosis.

Patients and Methods

We selected 21 of the most frequently studied SNPs in the TP53 pathway and evaluated their association with outcome in 500 neuroblastoma patients using TaqMan allelic discrimination assays.

Results and Conclusion

We investigated the impact of 21 SNPs on overall survival, event-free survival, age at diagnosis, MYCN status, and stage of the disease in 500 neuroblastoma patients. A missense SNP in exon 10 of the CASP8 gene SNP D302H was associated with worse overall and event-free survival in patients with MYCN-amplified neuroblastoma tumors.     

Identification,synthesis and SAR of amino substituted pyrido[3,2b]pyrazinones as potent and selective PDE5 inhibitors

A new class of potent and selective PDE5 inhibitors is disclosed. Guided by X-ray crystallographic data, optimization of an HTS lead led to the discovery of a series of 2-aryl, (N8)-alkyl substituted-6-aminosubstituted pyrido[3,2b]pyrazinones which show potent inhibition of the PDE5 enzyme. Synthetic details and some structure–activity relationships are also presented.     

Expression and function of phospholipase C in breast carcinoma

Phosphoinositide-specific phospholipase C (PLC) control the levels of their substrate phosphatidylinositol 4,5-bisphosphate (PI(4,5)P₂), and its hydrolysis products diacylglycerol (DAG) and Ins(1,4,5)P₃, second messengers key to growth control and cell movement. The former is modulated by breakdown of plasma membrane and nuclear phosphoinositides, while the latter is mediated by phosphoinositide-driven remodeling of the actin cytoskeleton. The roles of PLC in the etiology and progression of breast carcinoma, however, are poorly understood. Previous studies reported a correlation between PLCβ₂ expression and breast tumor grade, making PLCβ₂ a potential marker for clinical outcome (Bertagnolo et al., 2006). While over-expression of PLCβ₂ is not sufficient to induce transformation of normal breast epithelial cells, it appears to play a role in promoting cell migration (Bertagnolo et al., 2007).Here we examined the expression of this and other PLC mRNA (β₁–β₄, δ₁, δ₃ and δ₄, γ₁ and γ₂) in normal breast epithelial lines, MCF-10A, and compared that pattern to breast tumor lines MDA-MB-231 and to T47D, using real-time relative-quantification PCR. Our results show that PLCγ₁, γ₂ and δ₁ and δ3 are more highly expressed in the transformed cell lines compared to MCF-10A when normalized to mRNA encoding various house keeping proteins; whereas PLCβ₂ mRNA levels were considerably lower than other PLC subtypes, including PLCβ₁ in the metastatic lines. Examination of PLC mRNA levels from normal and cancerous human breast tissue showed a similar pattern of expression, however, when staging or tumor size was considered, PLCδ₁ and δ₃ expression were positively correlated.To test whether PLCδ₁ or δ₃ played any role in tumor cell proliferation or cell migration, we transfected cells with siRNA specifically targeting these isoforms. RNAi mediated knockdown of either PLC isoform, reduced proliferation of the MDA-MB-231 cells. Morphological changes including cell rounding, and surface blebbing and nuclear fragmentation were observed. These changes were accompanied by reductions in cell migration activities. On the other hand, PLCδ₁ knockdown failed to cause comparable morphological changes in the normal MCF-10A line, but did reduce cell proliferation and migration. Taken together, these data are consistent with the idea that PLCδ₁ and δ₃ isoforms support the growth and migration of normal and neoplastic mammary epithelial cells in vitro.