Synthesis of [11-2H2], [8-2H2], [7-2H2], [6-2H2], [5-2H2], [4-2H2] and [3-2H2] cis-9-octadecenoates

Deuterated oleates have been synthesized by semihydrogenation of acetylenic intermediates. [11-²H₂]Oleate was prepared by two-carbon chain extension of the C₁₆ alcohol obtained from [1-²H₂]octyl bromide and 7-octyn-1-ol. [8-²H₂] and [7-²H₂]oleates were both prepared from dimethyl suberate, tetradeutero intermediate C₁₆ alcohols were synthesized from [1,8-²H₄] and [2,7-²H₄]octane diols by monobromination, conversion to deuterated 9-decyn-1-ols and reaction with octyl bromide. Oxidation gave [8-²H₂]-9-octadecynoate and [2,7-²H₂]-9-octadecynoate, after semihydrogenation of the latter, deuterons at C-2 were removed by exchange with aqueous alkali. [6-²H₂] and [5-²H₂]oleates were obtained from methyl 5-tetradecynoate, semihydrogenation, deuterium exchange at C-2 and two malonate extensions gave [6-²H₂]oleate; reduction with lithium aluminum deuteride, two malonate extensions and semihydrogenation gave the [5-²H₂] ester. [4-²H₂] and [3-²H₂]oleates were both obtained from methyl 7-cis-hexadecenoate, exchange of the α protons and chain extension gave the [4-²H₂] ester and reduction with lithium aluminum deuteride and chain extension gave the [3-²H₂] ester.     

Binding Patterns of Rotavirus Genotypes P[4], P[6], and P[8] in China with Histo-Blood Group Antigens

Rotaviruses (RVs) are an important cause of severe gastroenteritis in children. It has been found that RV may recognize the histo-blood group antigens (HBGAs) as ligands or receptors and bind HBGAs in a type-dependent manner. In this study, we investigated the binding specificity of VP8* proteins from human rotaviruses (RV) that are prevalent in China including genotypes P[4], P[6], and P[8]. Through the saliva- and oligosaccharide-based binding assays, we found that the VP8* proteins of P[4] and P[8] RV showed similar reactivity with the Le^b and H type 1 antigens, while P[6] RV weakly bound the Le^b antigen. These findings may facilitate further research into RV host specificity and vaccine development.     

Synthesis of methyl [18-2H3], [17-2H2], [16-2H2], [14-2H2] and [12-2H2] cis-9-octadecenoates

Methyl [17-²H₂]oleate was prepared by stepwise reduction from 17-oxooleate in 24% yield. Methyl [18-²H₃], [16-²H₂], [14-²H₂] and [12-²H₂] oleates were synthesized from appropriately deuterated octylbromides by conversion to deuterated 7-hexadecyn-1-ols and chain extention to deuterated stearolates followed by semihydrogenation; overall yields were about 17%.     

How to find a prion: [URE3], [PSI+] and [beta

Infectious proteins (prions) in yeast or other microorganisms can be identified by genetic methods of rather general applicability. Infection in yeast means transfer by cytoplasmic mixing (cytoduction), a property of all non-chromosomal genetic elements whether plasmids, viruses, or prions. Prions can be diagnosed by reversible curability, increased occurrence when the corresponding protein is overproduced, a requirement for the gene for the corresponding protein for propagation, and, in some cases, similarity of phenotype of: (a) mutations in the gene for the protein and (b) the presence of the prion. This approach is illustrated with [URE3], an amyloid-based prion of the regulator of nitrogen catabolism, Ure2p and [PSI(+)] as a prion of the translation termination factor Sup35p. The prion concept is not limited to infectious amyloids, but includes proteins whose active form is necessary for the activation of the inactive precursor. We detail methods used in studies of [URE3] and [beta], a self-activating protease, some of which are of broad application.     

Host discrimination byChelonus insularis [Hym.: Braconidae], telenomus heliothidis [Hym.: Scelionidae], andTrichogramma pretiosum [Hym.: Trichogrammatidae]

The ability of female parasitoids (Chelonus insularis Cresson,Telenomus heliothidis Ashmead, andTrichogramma pretiosum Riley) to distinguish between parasitized and unparasitized tobacco budworm,Heliothis virescens (F.), eggs was determined in laboratory studies. All 3 species were relatively efficient at detecting eggs that were previously parasitized by conspecific females.T. heliothidis andT. pretiosum were able to discriminate on the basis of external examination of host eggs, whereasC. insularis appeared to examine hosts internally as well as externally. In interspecific tests, no species readily rejected eggs parasitized by the other 2 species.     

Conformational change of ascidiacyclamide caused by asymmetric modification for an isoleucine residue: structural analyses of [Gly], [Leu], and [Phe]ascidiacyclamides by x-ray diffraction and NMR spectroscopy

Ascidiacyclamide, a cytotoxic cyclic peptide from tunicate, is composed of unusual amino acids and has a repeated sequence, c[-thiazole-D-Val-oxazoline-L-Ile-]2 ([Ile]ASC). The symmetric chemical structure has been assumed to be correlated with the cytotoxicity, and it is reasonable to consider that the disturbance of its structure from the C2 symmetry results in the changes of conformation and activity. In order to quantitatively estimate the molecular conformation-activity relationship, an isoleucine residue was substituted by Gly, Leu, or Phe to disturb the C2 symmetry. The conformations of three derivatives were examined by nmr spectroscopy and the crystal structure of [Leu]ASC was also analyzed by x-ray diffraction method. The 1H-nmr experiments and the constrained molecular dynamics simulations showed the twisted "figure 8" conformers for [Gly] and [Phe]ASCs and the "square" conformer for [Leu]ASC in the DMSO solution. The x-ray crystal analysis of [Leu]ASC also revealed the square form similar to the solution structure. On the other hand, their cytotoxic activities were measured using L1210 leukemia cells and were related with the bulkiness and/or hydrophobicity of the side chain of the substituted amino acid; [Phe] > or = [Ile] > [Leu] > [Gly]ASCs. As an attempt to consider the correlation between the activity and conformer, the accessible surface area (ASA) was calculated for each derivative to estimate the size or bulkiness of its conformation. Although the ASAs of nmr structures were not directly related to the type of conformer (figure 8 or square form), it was an important probe to consider the cytotoxicity of each derivative.     

Preliminary studies on the efficacy and establishment ofRoptrocerus xylophagorum [Hym.: Torymidae], a parasitoid ofIps grandicollis [Col.: Scolytidae], in Australia

Parasitization ofIps grandicollis Eichhoff byRoptrocerus xylophagorum (Ratzeburg), and intra-specific competition withinIps broods, were studied under laboratory conditions. Largest numbers of immatureR. xylophagorum were found in logs sampled when about half theIps brood were callow adults. Rates of parasitization rarely exceeded 20 %, and were usually much lower. Numbers of parasitoids were not affected by bark thickness. In the absence of parasitism,Ips broods suffered a density-dependent mortality which increased greatly in intensity and continued to act later in development of the broods when initial densities of larvae exceeded a threshold of about 400 per 1 000 cm² of bark. The possible significance of this mortality is discussed in relation to the ability of parasitoids to reduceIps numbers. A field experiment was done to investigate the ability ofR. xylophagorum to establish in a new habitat. Populations were established for 1 or more generations by releasing 50 females at sites prepared by supplying small numbers of logs containing immatureIps.     

Magnetic circular dichroism studies of succinate dehydrogenase. Evidence for [2Fe-2S], [3Fe-xS], and [4Fe-4S] centers in reconstitutively active enzyme

Reconstitutively active and inactive succinate dehydrogenase have been investigated by low temperature magnetic circular dichroism (MCD) and EPR spectroscopy and room temperature CD and absorption spectroscopy. Reconstitutively active succinate dehydrogenase is found to contain three spectroscopically distinct Fe-S clusters: S1, S2, and S3. In agreement with previous studies, MCD and CD spectroscopy confirm that center S1 is a succinate-reducible [2Fe-2S]2+,1+ center. The MCD characteristics of center S2 identify it as a dithionite-reducible [4Fe-4S]2+,1+ similar to those in bacterial ferredoxins. EPR power saturation studies and the weakness of the EPR signal from reduced S2 indicate that there is a weak magnetic interaction between centers S1 and S2 in their paramagnetic, S = 1/2, reduced states. Center S3 is identified both by the form of the MCD spectrum and the characteristic magnetization behavior as a reduced [3Fe-xS] center in both succinate- and dithionite-reduced reconstitutively active succinate dehydrogenase. Arguments are presented in favor of centers S2 and S3 being separate centers rather than interconversion products of the same cluster. Reconstitutively inactive succinate dehydrogenase is found to be deficient in center S3. These results resolve many of the controversies concerning the Fe-S cluster content of succinate dehydrogenase and reconcile published EPR data with analytical and core extrusion studies. Moreover, they indicate that center S3 is a necessary requirement for reconstitutive activity and suggest that it is able to sustain ubiquinone reductase activity as a [3Fe-xS] center.     

Novel gamma-1 herpesviruses identified in free-ranging new world monkeys (golden-handed tamarin [Saguinus midas], squirrel monkey [Saimiri sciureus], and white-faced saki [Pithecia pithecia]) in French Guiana

The recent finding of a novel Epstein-Barr virus-related lymphocryptovirus (CalHV-3) in a captive colony of common marmoset (Callithrix jacchus) in the United States modifies the view that the host range of lymphocryptovirus is restricted to humans and Old World primates. We investigated the presence of Epstein-Barr virus-related viruses in 79 samples of New World monkeys caught in the wild, including six species of the Cebidae family and one of the Callitrichidae, living in the rain forest of French Guiana. Using a degenerate consensus PCR method for the herpesvirus DNA polymerase gene, we identified three novel lymphocryptoviruses from golden-handed tamarin (Saguinus midas) of the Callitrichidae family and squirrel monkey (Saimiri sciureus) and white-faced saki (Pithecia pithecia) of the Cebidae family. With the CalHV-3 strain, these three novel viruses constitute a well-supported phylogenetic clade in the Lymphocryptovirus genus, which is clearly distinct from the lineage of Old World lymphocryptovirus, hosted by catarrhine monkeys and humans. In tamarins, the prevalence of the novel lymphocryptovirus was more than 50%, indicating that it circulates well in the wild population, perhaps due to specific ecoethological patterns such as confrontations and intergroup migration. The detection and partial molecular characterization of the polymerase gene of three novel Gamma-1-Herpesvirinae from New World monkeys caught in the wild clearly indicate that free-ranging populations of platyrrhine are natural hosts of lymphocryptoviruses. Further characterization of these novel viruses will provide new insight not only into the origin and evolution of Gammaherpesvirinae but also into their pathogenicity.     

Nocturnal stomatal conductance responses to rising [CO2], temperature and drought

The response of nocturnal stomatal conductance (g(s,n)) to rising atmospheric CO(2) concentration ([CO(2)]) is currently unknown, and may differ from responses of daytime stomatal conductance (g(s,d)). Because night-time water fluxes can have a significant impact on landscape water budgets, an understanding of the effects of [CO(2)] and temperature on g(s,n) is crucial for predicting water fluxes under future climates. Here, we examined the effects of [CO(2)] (280, 400 and 640 μmol mol(-1)), temperature (ambient and ambient + 4°C) and drought on g(s,n,) and g(s,d) in Eucalyptus sideroxylon saplings. g(s,n) was substantially higher than zero, averaging 34% of g(s,d). Before the onset of drought, g(s,n) increased by 85% when [CO(2)] increased from 280 to 640 μmol mol(-1), averaged across both temperature treatments. g(s,n) declined with drought, but an increase in [CO(2)] slowed this decline. Consequently, the soil water potential at which g(s,n) was zero (Ψ(0)) was significantly more negative in elevated [CO(2)] and temperature treatments. g(s,d) showed inconsistent responses to [CO(2)] and temperature. g (s,n) may be higher in future climates, potentially increasing nocturnal water loss and susceptibility to drought, but cannot be predicted easily from g(s,d). Therefore, predictive models using stomatal conductance must account for both g(s,n) and g(s,d) when estimating ecosystem water fluxes.     

Conformational study of cyclo[D-Trp-D-Asp-Pro-D-Val-Leu], an endothelin-A receptor-selective antagonist.

The conformation of cyclo[D-Trp-D-Asp-Pro-D-Val-Leu], (BQ123), an endothelin-A receptor-selective antagonist, has been studied in 20% acetonitrile in water by CD and NMR spectroscopy. CD studies showed the peptide adopted a similar, constrained conformation in both water alone and 20% acetonitrile in water. NMR spectra showed the proline residue to be in the trans conformation and 2 of the NH protons to exchange slowly with the solvent, indicating hydrogen bonding. Structural constraints derived from the NMR spectra were used to define the conformation in molecular dynamics simulations. A single backbone conformation is observed for the cycle, comprising a beta type II turn and a gamma' turn.     

Interaction of LDL, Lp[a], and reduced Lp[a] with monoclonal antibodies against apoB

Five monoclonal antibodies (2A, 9A, 6B, L3, L7) produced in mice against human apolipoprotein B were investigated by competitive and inhibitive electroimmunoassay (EIA) for their reactivity with low density lipoprotein (LDL), lipoprotein[a] (Lp[a]), and reduced Lp[a]. All of the antibodies reacted with apoB of the different lipoproteins indicated by very similar slopes of the binding curves. None of them gave a positive reaction with apolipoprotein[a]. The amount of apoB required for 50% inhibition of antibody binding varied for the different antibodies and lipoproteins. Antibody 9A showed almost the same affinity for LDL, Lp[a], and reduced Lp[a]. Antibodies 2A and 6B bound about twofold better to LDL and reduced Lp[a] than to untreated Lp[a]. Antibodies L3 and L7 needed nearly threefold higher amounts of Lp[a]-apoB for 50% inhibition of antibody binding than of apoB of LDL and reduced Lp[a]. The amount of apoB required for 50% inhibition of antibody binding was somewhat higher in inhibitive assay than in competitive assay. We suggest that apo[a] covers certain epitopes of apoB in native Lp[a] leading to a reduced reaction with the monoclonal antibodies. However, it could also be that the binding of the [a]antigen to apoB via disulfide bridges causes profound conformational changes of the apoB region exposed to the surface.     

Introduction,colonization and establishment ofLysiphlebus testaceipes [Hymenoptera: Aphidiidae], in Argentina

The introduction, colonization, and establishment ofLysiphlebus testaceipes (Cresson) for the biological control ofSchizaphis graminum (Rondani). in Argentina is briefly discussed.     

Biology and population development ofAblattaria arenaria [Coleoptera: Silphidae], a snail predator

The biology ofAblattaria arenaria (Kraatz) was studied in the laboratory by using a helicid snail,Xeropicta derbentina (Kyrnicki) as prey. Population development ofA. arenaria in the field was studied in 1985 and 1986. The eggs ofA. arenaria were laid in the soil in lots of 5–45 at various intervals, and the total number of eggs per female varied from 144 to 193 during the oviposition period of 24–88 days.A. arenaria passed through the egg, 3 larval, prepupal, and pupal stages before reaching the adult stage. The mean duration of these stages was 9.8, 3.9, 2.5, 5.9, 3.8 and 5.7 days, respectively, with a total of 31.4 days. A. arenaria overwintered as an adult and became active and laid eggs during the spring. The start of spring activity seemed to be highly influenced by relative humidity. High humidity resulted in early emergence from overwintering sites. There was 1 generation in 1985, but 2 population peaks occurred in 1986. Immature stages of the 2nd generation became adult before the beginning of aestivation. Activity of the beetles was stopped by the beginning of hot weather in June, which synchronized well with the beginning of snail aestivation.      

Co-curing of plasmids affecting killer double-stranded RNAs of Saccharomyces cerevisiae: [HOK], [NEX], and the abundance of L are related and further evidence that M1 requires L.

We describe two sets of plasmid-plasmid interactions in the yeast Saccharomyces cerevisiae. [HOK], [EXL], [NEX], and [KIL-k1] are genetically defined plasmids, and M1 and L are biochemically defined double-stranded RNA plasmids. We show that (i) [HOK], [NEX], and the abundance of L are related, and (ii) under submaximal curing conditions, all colonies retaining M1 also retain L. There are three pieces of evidence that either [NEX] required [HOK] for replication or [NEX] and [HOK] are on the same plasmid. The evidence is as follows. (i) The great majority of strains containing [HOK] also contain [NEX]. However, two [HOK] [NEX-o] strains do exist. (ii) Growth at 39 degrees C or growth at 34 degrees C with 3% ethanol or 2-propanol cures [HOK] and [NEX]. In a [HOK] [NEX] strain, the two plasmids are always co-cured. (iii) [HOK] and [NEX] are both maintained in mak4, mak6, and mak27 strains (mak = maintenance of [KIL-k1]), but not in mak3, mak10, and pet18 strains. Strains containing [HOK] and [NEX] have about fourfold more L double-stranded RNA than their isochromosomal, cured derivatives. In addition, a cytoductant which has acquired [HOK] and [NEX] has fourfold more L than its parent. These results are consistent with either [HOK] being a form of L or [HOK] increasing the copy number of L. Using a K1 killer strain in which L, as well as M1, could be cured by growth at 38 degrees C, we examined the distribution of loss of M1 and L under conditions giving 98% M-o colonies and at least 50% L-o colonies. No M1L-o colonies were observed, supporting the previous suggestion by others that M1 requires L.     

Ultraviolet Mutagenesis Studies of [psi], a Cytoplasmic Determinant of SACCHAROMYCES CEREVISIAE

UV mutagenesis was used to probe the molecular nature of [psi], a non-mitochondrial cytoplasmic determinant of Saccharomyces cerevisiae involved in the control of nonsense suppression. The UV-induced mutation from [psi⁺] to [psi^-] showed characteristics of forward nuclear gene mutation in terms of frequency, induction kinetics, occurrence of whole and sectored mutant clones and the effect of the stage in the growth cycle on mutation frequency. The involvement of pyrimidine dimers in the premutational lesion giving the [psi^-] mutation was demonstrated by photoreactivation. UV-induced damage to the [psi] genetic determinant was shown to be repaired by nuclear-coded repair enzymes that are responsible for the repair of nuclear DNA damage. UV-induced damage to mitochondrial DNA appeared to be, at least partly, under the control of different repair processes. The evidence obtained suggests that the [psi] determinant is DNA.     

To be or not to be [fertile], that is the question

Background

According to our literature analysis, there are no data focused on spermatozoa emotional representations in childless men and data on the emotional repercussions of a diagnosis of infertility on men are still scarce. Thus, in this work, we investigated what the presence or absence of spermatozoa in the semen symbolize for men.

Material and methods

To answer this question, 441 childless heterosexual men participated in an anonymous, prospective, Internet-based survey.

Results

In response to the question “What would having a high or normal sperm count symbolize for you?” the most frequent answer was “ability to father a child”. Men living with a partner were significantly more likely than single men to answer “ability to father a child” (p?<?0.05) and less likely to answer “virility” and/or “ability to have an erection/ejaculation” (p?=?0.001). In response to the question “If you found out that you had a low sperm count or no spermatozoa at all, how would you feel?”, most of the men stated that they would be disappointed. Men living with a partner were more likely to state that they would feel ashamed (p?<?0.05) or guilty with regard to their partner (p?<?0.0001).

Conclusions

These preliminary results should help us to improve (i) the way that male infertility is announced (it is easier to find the right words if one understands the possible importance of having a high sperm count) and (ii) the psychological, marital and sexual counselling provided to men with a diagnosis of infertility.

     

[S2], [S3], and [N3] coordination modes of hydrotris(thioxotriazolyl)borato. Zinc, nickel, cobalt, and bismuth complexes

The ligand hydrotris(1,4-dihydro-3-methyl-4-phenyl-5-thioxo-1,2,4-triazolyl)borato (Tr^Ph,Me) was synthetized as natrium salt and the complexes [Zn(Tr^Ph,Me)₂] · 7.5H₂O · 1.5CH₃CN (2a), [Zn(Tr^Ph,Me)₂] · 8DMF (2b), [Co(Tr^Ph,Me)₂] · 8DMF (3a), [Ni(Tr^Ph,Me)₂] · H₂O · 6DMSO (4a), [Bi(Tr^Ph,Me)₂]NO₃ (5), have been isolated and structurally characterized by X-ray diffraction. In the zinc derivatives the ligand adopts different denticity and coordination modes, η² and [S₂] for 2a and η³ and [N₃] for 2b, depending on the crystallization solvent, giving rise to tetrahedral and octahedral geometry, respectively. In the octahedral cobalt and nickel complexes the ligand is η³ and [N₃] coordinated whereas in the bismuth complex the η³ and [S₃] coordination is exhibited.     

Biological studies ofClausenia josefi [Hym. Encyrtidae], a parasite ofPlanococcus vitis

Clausenia josefi, an internal primary parasite ofPlanococcus vitis, was first found and described in 1963. A summary of studies involving duration of development, reproduction, sex ratio, and effect of host size on development, under both laboratory and outdoor conditions, is presented.     

Biological studies ofBrachyserphus abruptus [Hym.: Proctotrupidae], a nitidulid parasite

Data are presented on survival, fecundity, and hosts ofBrachyserphus abruptus (Say), a solitary internal parasite of nitidulid (sap beetle) larvae. In the laboratory these wasps have been successfully reared fromCarpophilus hemipterus (L.),C. freemani Dobson,C. lugubris Murray,Stelidota geminata (Say),S. octomaculata (Say),S. ferruginea Reitter,Glischrochilus quadrisignatus (Say),Lobiopa insularis (Castelnau), andHaptoncus luteolus (Erichson). Field collections ofB. abruptus have been made fromS. geminata, S. octomaculata, C. hemipterus, C. lugubris, L. insularis andH. luteolus. Oviposition continues throughout most of the adult female's lifetime. Under laboratory conditions life expectancy of females wasca. 6 days. Mean number of progeny reaching adulthood per female was 57, with a 1∶1 sex ratio. First and 2^nd instar nitidulids were suitable for successful development ofB. abruptus. Third instars were attacked byB. abruptus but were not successfully parasitized. Parasite development required 29 days in 1^st instar hosts and 27 d. in 2^nd instars. Percent parasitism in 1^st instarC. hemipterus averaged 65% and for 2^nd instar 45%. After parasitism, larvae ofC. hemipterus surviving to become adults averaged 0.6% for 1^st instar, 9.3% for 2^nd instar, and 90% for 3^rd instar. This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation for its use by The Ohio State University.