Suppression of prolactin does not reduce infant care by parentally experienced male common marmosets (Callithrix jacchus)

High levels of prolactin have been found to correlate with the expression of paternal care in a variety of taxa. However, in mammals, there is little experimental evidence that prolactin is causally involved in the stimulation or maintenance of paternal care. Here, we suppressed prolactin production in paternally experienced common marmoset fathers in their family groups during the first 2 weeks after their infants were born. Circulating prolactin levels were suppressed using cabergoline (Dostinex: Pfizer), a long acting dopamine (D2) agonist with minimal behavioural side-effects. A within-subject design was used to compare behavioural and hormonal data on 5 paternally experienced fathers during two consecutive births. Cabergoline reduced prolactin to negligible levels in all fathers without effecting testosterone, DHT and cortisol and without adverse side-effects. However, lowering prolactin had no significant effect on the expression of majority of the behaviour patterns associated with paternal care. These included infant carrying, infant grooming and the frequency with which fathers retrieved and rejected infants. The only infant-related behaviour to be affected was the frequency with which fathers touched, licked and investigated infants. We noted a marginally significant increase in this behaviour during cabergoline treatment. Despite the lack of effect on paternal care, cabergoline did exert an effect on the affiliative/sexual behaviour of fathers as there was a significant increase in the grooming behaviour fathers directed at and received from their mates during drug treatment. This study showed that experienced male marmosets can express paternal behaviour in the absence of the high prolactin levels normally seen after infants are born.     

Inflorescence and floral ontogeny in Crocus sativus L. (Iridaceae)

Inflorescence and floral ontogeny of the perennial, herbaceous crop Crocus sativus L. were studied using epi-illumination light microscopy. After production of leaves with helical arrangement a determinate inflorescence forms which becomes completely transformed into a single terminal flower. In some cases, bifurcation of the inflorescence meristem yields two or three floral meristems. The order of floral organs initiation is outer tepals – stamens – inner tepals – carpels. Stamens and outer tepals are produced from the lateral bifurcation of three common stamen-tepal primordia. Within each whorl, organs start developing unidirectionally from the adaxial side, except for the stamens which begin to grow from the abaxial side. Specialized features during organ development include interprimordial growth between tepals forming a perianth tube, fusion at the base of stamen filaments, and formation of an inferior ovary with unfused styles.     

Identification of candidate SNPs for drug induced toxicity from differentially expressed genes in associated tissues

The growing collection of publicly available high-throughput data provides an invaluable resource for generating preliminary in silico data in support of novel hypotheses. In this study we used a cross-dataset meta-analysis strategy to identify novel candidate genes and genetic variations relevant to paclitaxel/carboplatin-induced myelosuppression and neuropathy. We identified genes affected by drug exposure and present in tissues associated with toxicity. From ten top-ranked genes 42 non-synonymous single nucleotide polymorphisms (SNPs) were identified in silico and genotyped in 94 cancer patients treated with carboplatin/paclitaxel. We observed variations in 11 SNPs, of which seven were present in a sufficient frequency for statistical evaluation. Of these seven SNPs, three were present in ABCA1 and ATM, and showed significant or borderline significant association with either myelosuppression or neuropathy. The strikingly high number of associations between genotype and clinically observed toxicity provides support for our data-driven computations strategy to identify biomarkers for drug toxicity.     

鲤IGF2b基因5'侧翼区序列克隆及不同鲤该区域GC富集区的甲基化分析

鲤(Cyprinus carpio)胰岛素样生长因子2b(insulin-like growth factor 2b,IGF2b)基因为鲤IGF基因家族重要的成员,已有的研究表明5'侧翼区序列对其功能的发挥有重要作用。因此,采用基因组步移法获取5'侧翼区序列,通过亚硫酸盐修饰的方法分析不同品种该区域GC富集区的甲基化状况。本文成功从鲤基因组DNA中获得695 bp的IGF2b 5'侧翼区序列。已获取的IGF2b 5'侧翼区序列经过TFSEARCH分析后发现了多个转录因子结合位点和TATA框,通过BLAST比对发现,鲤IGF2b 5'侧翼区DNA序列与斑马鱼(Danio rerio)IGF2b基因相比,相似性为87%。检测该区域富含GC的序列17个位点,发现建鲤(C.c.var.jian)有2个个体的3个位点出现甲基化,而黄河鲤(C.c.haematopterus)只有1个个体1个位点出现甲基化,这说明2个品种鲤在这个区域出现甲基化修饰的几率低,也验证了这2品种在该基因该区域GC富集区是稳定的。     

Minimally invasive transabdominal collection of preimplantation embryos from the common marmoset monkey (Callithrix jacchus)

A novel, minimally invasive, transabdominal embryo collection method (transabdominal method) was developed as an alternative to a standard abdominal incision for embryo collection in the common marmoset. The abdominal incision method was used for 304 flushes using 36 female animals, whereas the transabdominal method was used for 488 flushes using 48 females; successful embryo collection rates were 48.0% and 48.4% (P > 0.05), respectively. These techniques were successfully duplicated at another institute (German Primate Center, DPZ). At that institution, successful embryo collection rates were 88.9% and 77.8% for the abdominal incision and transabdominal methods, respectively (P > 0.05), whereas the average numbers of preimplantation embryos obtained per flush were (mean ± SD) 1.91 ± 0.35 and 1.71 ± 0.14 (P > 0.05). The transabdominal method reduced animal stress, did not require incisional wound healing, and enabled successive embryo recoveries to be done much sooner. More embryos in early developmental stages (zygotes/morulae) were recovered using the transabdominal method (76.1%) than the abdominal incision method (52.6%, P < 0.01). In contrast, recovery of arrested or abnormal embryos was not significantly different between these two methods (9.8% and 8.3%). To verify developmental ability of embryos recovered by the transabdominal method, transfer of 28 normal embryos to 14 surrogate mothers yielded a nidation rate of 57%. Five females sustained term pregnancies and eight neonates were born. This novel transabdominal method will facilitate progress in marmoset developmental biology and embryology.     

Life history traits variation in heterogeneous environment: The case of a freshwater snail resistance to pond drying

Ecologists and population geneticists have long suspected that the diversity of living organisms was connected to the structure of their environment. In heterogeneous environments, diversifying selection combined to restricted gene flow may indeed lead to locally adapted populations. The freshwater snail, Galba truncatula, is a good model to address this question because it is present in a heterogeneous environment composed of temporary and permanent waters. In order to test the selective importance of those environments, we proposed here to measure survival of lineages from both habitats during drought episodes. To this purpose, we experimentally submitted adults and juveniles individuals from both habitats to drought. We found a difference in desiccation resistance between temporary and permanents waters only for adults. Adults from temporary habitats were found more resistant to drought. This divergence in desiccation resistance seems to explain the unexpected life history traits differences between habitats observed.     

3×3完全双列杂交F1不同阶段生长特点的分析

为了了解鲤杂交F1不同组合、不同阶段生长性状的变化情况,研究以建鲤、黄河鲤和黑龙江野鲤3个鲤品种双列杂交F1为试验材料,通过组合、组合内性别间、性别、不同时期体重、体增重以及协方差分量的分析,来确定完全双列杂交F1生长性状的变化特点,以及在此过程中起重要作用的影响因素。结果表明:不同时期各个组合体重不同,不同时期组合内性别间体重差异不同;不同时期不同性别间体重差异不同;不同协方差分量,同一组合PIT标记17个月时的体重的最小二乘估计值不同,同一个协方差分量,9个组合中极值估计值出现的组合也不同;除PIT标记17个月后的体厚作为协方差分量外,性别之间体重没有差异,其余分量均是雌鱼体重显著高于雄鱼体重。这些说明选取合适的协方差分量对组合的选择和育种的结果有重要影响。     

One-third rules with equality: Second-order evolutionary stability conditions in finite populations

The one-third law of evolutionary dynamics [Nowak et al. 2004. Emergence of cooperation and evolutionary stability in finite populations. Nature 428, 246-650] describes a robustness criterion for evolution in a finite population: If at an A-frequency of 1/3, the fitness of an A player is greater (smaller) than the fitness of a B player, then a single A mutant that appears in a population of otherwise all B has a fixation probability greater (smaller) than the neutral threshold 1/N, the inverse population size. We examine the case where at an A-frequency of 1/3, the fitness of an A player is exactly equal to the fitness of a B player. We find that in this case the relative magnitude of the cross payoffs matters: If the payoff of A against B is larger (smaller) than the payoff of B against A, then a single A mutant has a fixation probability larger (smaller) than 1/N. If the cross payoffs coincide, we are in the special case of a partnership game, where the deviation cost from an inefficient equilibrium is exactly balanced by the potential gain of switching to the payoff dominant equilibrium. We show that in this case the fixation probability of A is lower than 1/N. Finally, we illustrate our findings by a language game with differentiated costs of signals.     

Non-management of Natural Resources: The Case of Inland Fisheries in the Mayan Zone,Quintana Roo,México

This study explores the management of inland fisheries on common lands (ejidos) within the Mayan Zone of Quintana Roo, Mexico. Qualitative survey data are used to examine whether there are (a) ongoing fishery conservation activities; (b) local caretakers of fishing sites; (c) restrictions on where fishing can take place; and (d) particular groups of individuals who lack the right to fish within the ejidos. Results indicate that in contrast to other local resources, fisheries in the ejidos have less defined use rights, being viewed as largely “open access”. In particular, most feel that outsiders can fish in an ejido if they abide by local rules (notably not damaging the local water bodies, asking consent to fish, and having a friend or relative in the community). However, there are within-community differences in views concerning management and conservation, with those more dependent on fishing being more likely to support exclusion of outsiders.     

Plasmid content of salt stress-tolerant <Emphasis Type="Italic">Rhizobium</Emphasis> strains from Egyptian soils nodulating common bean (<Emphasis Type="Italic">Phaseolus vulgaris</Emphasis> L.)

Plasmid profile analysis is useful to characterize Rhizobium strains within the same species. Among the 16 Rhizobium strains examined, 14 had distinct plasmid profiles. The size of plasmids ranged from 40 to 650 kb, and three plasmids of 650, 510 and 390 kb were common to several strains. Plasmid analysis revealed that Rhizobium etli contained a mega-plasmid, similar in size to Rhizobium tropici. All the salt-tolerant strains examined had a plasmid of 250 kb, except for strain EBRI 29. This suggests that this plasmid may play an important adaptive role under salt stress conditions.