La Préparation et l’isomérisme géometrique des Acides Cinnamiques Méthylthio-α Substitués

An improved method of preparation and the separation of geometrical isomers of cis and trans α-methylthio-cinnamic acid derivatives are described. The observation on the NMR spectra and the determination of geometrical structure of these compounds by various spectrometric methods are also included.     

Synthesis of 7-Deoxy-d-glycero-d-gluco-heptose (SF-666A)

The synthesis of 7-deoxy-d-glycero-d-gluco-heptose (1) from 3,5-O-benzylidene-1,2-O-isopropylidene-α-d-glucofuranose (2) is described. Oxidation of compound (2) afforded 3,5-O-benzylidene-1,2-O-isopropylidene-α-d-gluco-hexodialdo-1,4-furanose (3), which was then treated with methylmagnesium iodide to give 3,5-O-benzylidene-1,2-O-isopropylidene-7-deoxy-α-d-glycero-d-gluco-heptose (4) and its l-glycero-d-gluco isomer (5). Hydrolysis of (4) produced compound (1), which was identical with natural SF-666 A, a fermentation product of Streptomyces setonensis nov. sp.     

Theoretical approach to the functional optimisation of spiriferide brachiopod shell: Optimum morphology of sulcus

Evidence suggests that biological forms that provide physiological and autecological functions have evolved to adapt to environmental conditions and to optimise requisite morpho-functions. We examined whether shell morphology is functionally optimised to generate passive feeding flow in the Devonian spiriferide brachiopod Paraspirifer bownockeri. This study was based on quantitative results from a computational fluid dynamics simulation and the Lagrangian multiplier method. We estimated the optimum development of the ventral median shell depression, which is called the sulcus, by minimising the pressure difference along the gape. This estimation was made under the constraint that the number of spiral flow rotations must be greater than one, which is effective for spiriferide feeding because of its alignment with the spiral lophophore. During mathematical optimisation, the equation resulted in a suitable flow velocity of approximately 0.1 m/s. At this velocity, the pressure difference was minimised, regardless of sulcus development. The constraint equation showed that the number of spiral flow rotations increased with sulcus development. The optimal solution was similar to the original sulcus form of Paraspirifer under an ambient flow of approximately 0.1 m/s. This result suggests that the variation of shell outline in spiriferids could provide a variety of preferential conditions for ambient flow and that the flow intensity could be adjusted by sulcus development to generate a robust passive feeding flow along the spiral feeding organs.     

Synthesis of N-substituted N-nitrosohydroxylamines as inhibitors of mushroom tyrosinase

A series of N-substituted N-nitrosohydroxylamines including six new compounds were synthesized and examined for inhibition of mushroom tyrosinase. Corresponding hydroxylamines were reacted with n-butyl nitrite to give substituted nitrosohydroxylamines as their ammonium salt. The N-substituted hydroxylamines were prepared from the primary amines via the oxaziridine, or from the carbonyl compounds via the oxime. Most of the nitrosohydroxylamines tested inhibited mushroom tyrosinase. Among them, N-cyclopentyl-N-nitrosohydroxylamine exhibited the most potent activity (IC(50)=0.6 microM), as powerful as that of tropolone, one of the most powerful inhibitors. As removal of nitroso or hydroxyl moiety, the enzyme inhibitory activity was completely diminished. Both N-nitroso group and N-hydroxy group were suggested to be essential for the activity, probably by interacting with the copper ion at the active site of the enzyme. Lineweaver-Burk plotting showed that cupferron was a competitive inhibitor but that N-cyclopentyl-N-nitrosohydroxylamine was not.     

Prospective study on the association between harm avoidance and postpartum depressive state in a maternal cohort of Japanese women

Background

Recent studies have displayed increased interest in examining the relationship between personality traits and the onset, treatment response patterns, and relapse of depression. This study aimed to examine whether or not harm avoidance (HA) was a risk factor for postpartum depression measured by the Edinburgh Postnatal Depression Scale (EPDS) and the state dependency of HA.

Methods

Pregnant women (n=460; mean age 31.9±4.2 years) who participated in a prenatal program completed the EPDS as a measure of depressive state and the Temperament and Character Inventory (TCI) as a measure of HA during three periods: early pregnancy (T1), late pregnancy (around 36 weeks), and 1 month postpartum (T2). Changes in EPDS and HA scores from T1 to T2 were compared between the non depressive (ND) group and the postpartum depressive (PD) group.

Results

There was no significant difference in the level of HA between the ND and PD groups at T1. In the ND group, EPDS and HA scores did not change significantly from T1 to T2. In the PD group, both scores increased significantly from T1 to T2 (EPDS, p<0.0001; HA, p<0.048). In the ND and PD groups, a significant positive correlation was observed in changes in EPDS and HA scores from T1 to T2 (r=0.31, p=0.002).

Conclusions

These results suggest that HA cannot be considered a risk factor for the development of postpartum depression measured by EPDS. Furthermore, HA may be state dependent.     

Impact of vaccination on cytotoxic T lymphocyte immunodominance and cooperation against simian immunodeficiency virus replication in rhesus macaques

Cytotoxic T lymphocyte (CTL) responses play a central role in viral suppression in human immunodeficiency virus (HIV) infections. Prophylactic vaccination resulting in effective CTL responses after viral exposure would contribute to HIV control. It is important to know how CTL memory induction by vaccination affects postexposure CTL responses. We previously showed vaccine-based control of a simian immunodeficiency virus (SIV) challenge in a group of Burmese rhesus macaques sharing a major histocompatibility complex class I haplotype. Gag(206-216) and Gag(241-249) epitope-specific CTL responses were responsible for this control. In the present study, we show the impact of individual epitope-specific CTL induction by prophylactic vaccination on postexposure CTL responses. In the acute phase after SIV challenge, dominant Gag(206-216)-specific CTL responses with delayed, naive-derived Gag(241-249)-specific CTL induction were observed in Gag(206-216) epitope-vaccinated animals with prophylactic induction of single Gag(206-216) epitope-specific CTL memory, and vice versa in Gag(241-249) epitope-vaccinated animals with single Gag(241-249) epitope-specific CTL induction. Animals with Gag(206-216)-specific CTL induction by vaccination selected for a Gag(206-216)-specific CTL escape mutation by week 5 and showed significantly less decline of plasma viral loads from week 3 to week 5 than in Gag(241-249) epitope-vaccinated animals without escape mutations. Our results present evidence indicating significant influence of prophylactic vaccination on postexposure CTL immunodominance and cooperation of vaccine antigen-specific and non-vaccine antigen-specific CTL responses, which affects virus control. These findings provide great insights into antigen design for CTL-inducing AIDS vaccines.     

Accumulation of secretory granules in pituitary clonal cells derived from the epithelium of Rathke's pouch

Summary 2A8 clonal cells derived from the epithelium of Rathke's pouch of the fetal rat are essentially agranular when grown in vitro, in spite of their active secretion of hormones, i.e., ACTH, prolactin and growth hormone. These cells do not produce detectable amounts of thyrotrophic or gonadotrophic hormones in vitro. When the growth medium (Ham's F10) was supplemented with rat median eminence extract (MEE), l-thyroxin and fresh serum from hypophysectomized rats, some of the 2A8 cells accumulated and stored secretory granules which were characteristic of the cells of the intact pituitary gland. Typical thyrotrophic and gonadotrophic cells also became recognizable and all six anterior pituitary hormones were released into the culture medium. Growth of 2A8 cells in this modified culture medium resulted in an increased production of all hormones with increasing time in culture.These results indicate that the processes that lead to the accumulation of typical mature secretory granules which characterize the individual pituitary cell types are initiated or promoted by some unidentified factor or factors which are present in fresh rat serum. It is also apparent that fresh rat serum can promote the differentiation of gonadotrophs and thyrotrophs in vitro.Supported by USPHS Grant Am 12583 and Institutional Research Grant of The University of Texas Health Science Center at San Antonio, TexasThe authors wish to thank Mrs. Pauline Polette for her skillful technical assistance