Effectiveness of Vaginal-Implant Transmitters for Locating Elk Parturition Sites

ABSTRACT We assessed success of vaginal implant transmitters (VITs), deployed in 198 elk (Cervus elaphus nelsoni), in locating elk calving sites in western Wyoming, USA, in 2006–2007. We identified 60.3% of expelled VIT locations as definite or probable event markers and an additional 21.8% as possible event markers. Failure rate for VITs was 10.6%, and we found an additional 7.3% in improbable or impossible parturition sites. Vaginal implant transmitters were effective in locating calving and abortion sites and will facilitate definition of parturition habitat selection and parturition ranges of specific subpopulations.     

Chromosome numbers and meiotic analysis in the pre-breeding of <Emphasis Type="BoldItalic">Brachiaria decumbens</Emphasis> (Poaceae)

A total of 44 accessions of Brachiaria decumbens were analysed for chromosome count and meiotic behaviour in order to identify potential progenitors for crosses. Among them, 15 accessions presented 2n = 18; 27 accessions, 2n = 36; and 2 accessions, 2n = 45 chromosomes. Among the diploid accessions, the rate of meiotic abnormalities was low, ranging from 0.82% to 7.93%. In the 27 tetraploid accessions, the rate of meiotic abnormalities ranged from 18.41% to 65.83%. The most common meiotic abnormalities were related to irregular chromosome segregation, but chromosome stickiness and abnormal cytokinesis were observed in low frequency. All abnormalities can compromise pollen viability by generating unbalanced gametes. Based on the chromosome number and meiotic stability, the present study indicates the apomictic tetraploid accessions that can act as male genitor to produce interspecific hybrids with B. ruziziensis or intraspecific hybrids with recently artificially tetraploidized accessions.     

A new genus of Staphylinidae (Coleoptera) from the Lower Cretaceous: the first fossil rove beetles from the Southern Hemisphere

The fossil genus of rove beetles Apticax gen.n . with two new species, A. volans sp.n . and A. solidus sp.n., is described from the Nova Olinda Member of the Crato Formation in north‐eastern Brazil (Aptian–Albian, dated as 125–99.6 Ma old). Both species belong to the clade Staphylininae + Paederinae in the staphylinine group of subfamilies and are the first fossil true Staphylinidae to be described from the entire Southern Hemisphere. Although they resemble Paederinae, the low number of satisfactorily preserved characters do not allow definite placement of either A. volans or A. solidus in any of the subfamilies of Staphylinidae.     

Parthenogenesis did not consistently evolve in insular populations of Ischnura hastata (Odonata,Coenagrionidae)

1. The evolutionary advantages that have driven the evolution of sex are still very much debated, and a number of benefits of parthenogenesis over sexual reproduction have been proposed. In particular, parthenogenetic individuals are thought to exhibit higher probabilities of establishment following arrival in new, isolated habitats such as islands. 2. One notable example of parthenogenesis occurring in islands is the damselfly Ischnura hastata, an American species that has colonised the Azores archipelago, where the populations consist only of females. This is the only known example of parthenogenesis within the insect order Odonata. 3. Here, two island populations of I. hastata were studied, one in the Galapagos and one in Cuba, to test whether island colonisation is consistently associated with parthenogenesis in this species. Field capture–mark–recapture studies and laboratory rearing of field‐collected eggs were undertaken in both areas. 4. Sex ratios in the field were found to be heavily female‐biased among mature individuals; however, fertility rates of field‐collected eggs were high, and the sex ratios in the laboratory did not differ from 1 : 1. Data from laboratory rearing showed that shorter larval development times and shorter adult life spans in males result in protandry, which might explain the skewed sex ratios in the field. 5. These findings are consistent with sex differences in key demographic parameters which could predispose I. hastata to parthenogenesis. However, the Azores population of I. hastata remains the only documented case of asexual reproduction in this insect group.     

Human mesenchymal stromal cells do not promote recurrence of soft tissue sarcomas in mouse xenografts after radiation and surgery

Background. Mesenchymal stromal cells (MSCs) promote wound healing, including after radiotherapy (RT) and surgery. The use of MSCs in regenerative medicine in the context of malignancy, such as to enhance wound healing post-RT/surgery in patients with soft tissue sarcomas (STSs), requires safety validation. The aim of this study was to determine the effects of human MSCs on STS growth in vitro and local recurrence and metastasis in vivo. Methods. Human primary STS and HT-1080 fibrosarcoma lines were transduced to express luciferase/eGFP (enhanced green fluorescent protein). Sarcoma cells were co-cultured or co-injected with bone marrow–derived MSCs for growth studies. Xenograft tumor models were established with STS lines in NOD/SCID/γ_c^null mice. To emulate a clinical scenario, subcutaneous tumors were treated with RT/surgery prior to MSC injection into the tumor bed. Local and distant tumor recurrence was studied using histology and bioluminescence imaging. Results. MSCs did not promote STS proliferation upon co-culture in vitro, which was consistent among MSCs from different donors. Co-injection of MSCs with sarcoma cells in mice exhibited no significant tumor-stimulating effect, compared with control mice injected with sarcoma cells alone. MSC administration after RT/surgery had no effect on local recurrence or metastasis of STS. Discussion. These studies are important for the establishment of a safety profile for MSC administration in patients with STS. Our data suggest that MSCs are safe in STS management after standard of care RT/surgery, which can be further investigated in early-phase clinical trials to also determine the efficacy of MSCs in reducing morbidity and to mitigate wound complications in these patients.     

Dielectric-Gravimetric Measurements on Fucus vesiculosus and Ascophyllum nodosum During Dehydration

Careri, G., Giansanti, A. and Fensom, D. 1986. Dielectnc-gravimetricmeasurements on Fucus vesiculosus and Ascophyllum nodosum duringdehydration.—J. exp. Bot. 37: 375–378. Samples of the marine algae Fucus vesiculosus and Ascophyllumnodosum were dehydrated between plates of a condenser so thatsimultaneous measurements of dielectric properties and rateof water loss could be made. During the desiccation process,both the evaporation rate and the dielectric properties becomezero at a critical hydration H_c, indicating that for H <H_c,the residual water must be in a tightly bound state. The absolutevalues of H_c, depend on the nature of the sample, but they arein the range 0·1–0·3, well above the hydrationlimit for active ion uptake (H=0·02). It is concludedthat, in these fucoids, living cells are maintained in the hydrationregion where water is in the bound state only. Key words: Fucus, Ascophyllwn, dielectric, dehydration     

Pinocytosis of Ferritin from the Gut Lumen in Larvae of a Sea Star (Patiria miniata) and a Sea Urchin (Lytechinus pictus)

Pinocytosis of macromolecules from the gut lumen is demonstrated for the first time in larval stages of invertebrates. Developing sea stars ( Patiria miniata ) and sea urchins ( Lytechinus pictus ) were incubated in seawater containing ferritin, which was detected in cell organelles by transmission electron microscopy. Pinocytotic uptake of ferritin by gut cells of Patiria could be detected as soon as the larval mouth opened before the esophagus, stomach and intestine could be distinguished from one another; in contrast, no pinocytosis was detected at the comparable developmental stage (the prism larva) of Lytechinus . Pinocytosis was first detected in developing Lytechinus in pluteus larvae, especially in the stomach and intestine. In gut cells of both kinds of echinoderm larvae, the ferritin progressed rapidly from coated pits at the luminal cell membrane to secondary lysosomes (e.g. this progression took only about 10 min in stomach cells of Patiria larvae). Phagocytosis from the gut lumen was never observed after latex beads or starch granules were fed to larvae of Patiria and Lytechinus . Moreover, there was no evidence of pinocytosis of ferritin or phagocytosis of large particles by epidermal cells of larvae of either species.