Mutations in PNKP Cause Recessive Ataxia with Oculomotor Apraxia Type 4

Hereditary autosomal-recessive cerebellar ataxias are a genetically and clinically heterogeneous group of disorders. We used homozygosity mapping and exome sequencing to study a cohort of nine Portuguese families who were identified during a nationwide, population-based, systematic survey as displaying a consistent phenotype of recessive ataxia with oculomotor apraxia (AOA). The integration of data from these analyses led to the identification of the same homozygous PNKP (polynucleotide kinase 3′-phosphatase) mutation, c.1123G>T (p.Gly375Trp), in three of the studied families. When analyzing this particular gene in the exome sequencing data from the remaining cohort, we identified homozygous or compound-heterozygous mutations in five other families. PNKP is a dual-function enzyme with a key role in different pathways of DNA-damage repair. Mutations in this gene have previously been associated with an autosomal-recessive syndrome characterized by microcephaly; early-onset, intractable seizures; and developmental delay (MCSZ). The finding of PNKP mutations associated with recessive AOA extends the phenotype associated with this gene and identifies a fourth locus that causes AOA. These data confirm that MCSZ and some forms of ataxia share etiological features, most likely reflecting the role of PNKP in DNA-repair mechanisms.     

Antibacterial and antioxidant cassane diterpenoids from Caesalpinia benthamiana

Bioactivity-guided fractionation of the light petroleum extract of Caesalpinia benthamiana (=Mezoneuron benthamianum) root bark has led to the isolation of two cassane diterpenoids, designated as benthaminin 1 and 2. A third compound, a deoxy form of caesaldekarin C (also referred to as methyl vouacapenate) which has previously been isolated from Caesalpinia major, C. bonducella, Vouacapoua americana and V. macropetala, was also isolated, together with beta-sitosterol and stigmastenone. The antibacterial and antioxidant activities of these cassane diterpenoids have been assessed using the microdilution assay method and DPPH spectrophotometric and TBA lipid peroxidation assays. Benthaminin 1 was the more active antibacterial compound with MIC values of 47.8 microM for both Staphylococcus aureus and Micrococcus flavus. Benthaminin 2 was the more active antioxidant compound and showed IC50 values of 42.7 microM and 74.2 microM for the DPPH and TBA assays, respectively. Deoxycaesaldekarin C possessed both antibacterial and antioxidant activities. The presence of methyl ester and methyl functional groups as well as an unsaturated furan ring appears to confer antibacterial activity. On the other hand, the relatively stronger antioxidant activity of benthaminin 2 may be associated with the presence of an exocyclic methylene function.     

Lactobacillus-dominated cervicovaginal microbiota associated with reduced HIV/STI prevalence and genital HIV viral load in African women

Cervicovaginal microbiota not dominated by lactobacilli may facilitate transmission of HIV and other sexually transmitted infections (STIs), as well as miscarriages, preterm births and sepsis in pregnant women. However, little is known about the exact nature of the microbiological changes that cause these adverse outcomes. In this study, cervical samples of 174 Rwandan female sex workers were analyzed cross-sectionally using a phylogenetic microarray. Furthermore, HIV-1 RNA concentrations were measured in cervicovaginal lavages of 58 HIV-positive women among them. We identified six microbiome clusters, representing a gradient from low semi-quantitative abundance and diversity dominated by Lactobacillus crispatus (cluster R-I, with R denoting ‘Rwanda'') and L. iners (R-II) to intermediate (R-V) and high abundance and diversity (R-III, R-IV and R-VI) dominated by a mixture of anaerobes, including Gardnerella, Atopobium and Prevotella species. Women in cluster R-I were less likely to have HIV (P=0.03), herpes simplex virus type 2 (HSV-2; P<0.01), and high-risk human papillomavirus (HPV; P<0.01) and had no bacterial STIs (P=0.15). Statistically significant trends in prevalence of viral STIs were found from low prevalence in cluster R-I, to higher prevalence in clusters R-II and R-V, and highest prevalence in clusters R-III/R-IV/R-VI. Furthermore, only 10% of HIV-positive women in clusters R-I/R-II, compared with 40% in cluster R-V, and 42% in clusters R-III/R-IV/R-VI had detectable cervicovaginal HIV-1 RNA (P_trend=0.03). We conclude that L. crispatus-dominated, and to a lesser extent L. iners-dominated, cervicovaginal microbiota are associated with a lower prevalence of HIV/STIs and a lower likelihood of genital HIV-1 RNA shedding.     

In situ hybridization analysis of the temporospatial expression of the midkine/pleiotrophin family in rat embryonic pituitary gland

Pituitary gland development is controlled by numerous signaling molecules, which are produced in the oral ectoderm and diencephalon. A newly described family of heparin-binding growth factors, namely midkine (MK)/pleiotrophin (PTN), is involved in regulating the growth and differentiation of many tissues and organs. Using in situ hybridization with digoxigenin-labeled cRNA probes, we detected cells expressing MK and PTN in the developing rat pituitary gland. At embryonic day 12.5 (E12.5), MK expression was localized in Rathke’s pouch (derived from the oral ectoderm) and in the neurohypophyseal bud (derived from the diencephalon). From E12.5 to E19.5, MK mRNA was expressed in the developing neurohypophysis, and expression gradually decreased in the developing adenohypophysis. To characterize MK-expressing cells, we performed double-staining of MK mRNA and anterior pituitary hormones. At E19.5, no MK-expressing cells were stained with any hormone. In contrast, PTN was expressed only in the neurohypophysis primordium during all embryonic stages. In situ hybridization clearly showed that MK was expressed in primitive (immature/undifferentiated) adenohypophyseal cells and neurohypophyseal cells, whereas PTN was expressed only in neurohypophyseal cells. Thus, MK and PTN might play roles as signaling molecules during pituitary development.     

Diurnal patterns in Scots pine stem oleoresin pressure in a boreal forest

Coniferous tree stems contain large amounts of oleoresin under positive pressure in the resin ducts. Studies in North‐American pines indicated that the stem oleoresin exudation pressure (OEP) correlates negatively with transpiration rate and soil water content. However, it is not known how the OEP changes affect the emissions of volatile vapours from the trees. We measured the OEP, xylem diameter changes indicating changes in xylem water potential and monoterpene emissions under field conditions in mature Scots pine (Pinus sylvestris L.) trees in southern Finland. Contrary to earlier reports, the diurnal OEP changes were positively correlated with temperature and transpiration rate. OEP was lowest at the top part of the stem, where water potentials were also more negative, and often closely linked to ambient temperature and stem monoterpene emissions. However, occasionally OEP was affected by sudden changes in vapour pressure deficit (VPD), indicating the importance of xylem water potential on OEP as well. We conclude that the oleoresin storage pools in tree stems are in a dynamic relationship with ambient temperature and xylem water potential, and that the canopy monoterpene emission rates may therefore be also regulated by whole tree processes and not only by the conditions prevailing in the upper canopy.     

Prolactin induces chitotriosidase expression in human macrophages through PTK,PI3‐K,and MAPK pathways

We previously reported that prolactin (PRL) induces chitotriosidase (CHIT‐1) mRNA expression in human macrophages. In this investigation we determined the signaling pathways involved in CHIT‐1 induction in response to PRL. The CHIT‐1 induction PRL‐mediated was reduced by wortmannin and LY‐294002, inhibitors of phosphatidylinositol 3‐kinase (PI3‐K) and by genistein an inhibitor of protein tyrosine kinase (PTK). Pre‐treatment of macrophages with SB203580, a specific inhibitor of the mitogen‐activated kinases (MAPK) p38, or with U0126, an inhibitor of MAPK p44/42, prevented both basal and exogenous PRL‐mediated CHIT‐1 expression. No significant effects on CHIT‐1 induction PRL‐mediated were observed with a protein kinase C inhibitor (PKC), rottlerin, or with an Src inhibitor, PP2, or with JAK2 inhibitor, AG490. In addition, PRL induced a phosphorylation of AKT that was prevented both by the two MAPK inhibitors SB203580 and U0126 and by the PI3‐K inhibitors wortmannin and LY‐294002. In conclusion, our results indicate that PRL up‐regulated CHIT‐1 expression via PTK, PI3‐K, MAPK, and signaling transduction components. J. Cell. Biochem. 107: 881–889, 2009. © 2009 Wiley‐Liss, Inc.     

Stage dependent influences of polydnaviruses and the parasitoid larva on host ecdysteroids

In the solitary egg-larval parasitoid Chelonus inanitus (Braconidae) both polydnavirus and the parasitoid larva manipulate host development. Parasitization leads to a premature drop in juvenile hormone titre and a precocious onset of metamorphosis in the 5th larval instar. The C. inanitus bracovirus (CiBV) alone causes a reduction in host ecdysteroid titres at the pupal cell formation stage and prevents pupation. Here we report three new findings. (1) We show that parasitization causes a reduction in haemolymph ecdysteroid titre immediately after the moult to the 5th instar; similarly low values were seen in nonparasitized larvae after the moult to the 6th instar. These data along with parasitoid removal experiments indicate that the low ecdysteroid titre after the moult is a very early sign of the upcoming metamorphosis. (2) In vitro experiments with prothoracic glands and brain extracts showed that CiBV affects both prothoracic glands and prothoracicotropic hormone after the stage of pupal cell formation. (3) In the haemolymph of parasitized larvae the ecdysteroid titre increased in the late cell formation stage, i.e. immediately before egression of the parasitoid. In vitro experiments showed that late 2nd instar parasitoids release ecdysteroids and are thus very likely responsible for the rise in host ecdysteroids.     

Movement patterns and space use of the first giant anteater (Myrmecophaga tridactyla) monitored in São Paulo State,Brazil

This study analyzes a giant anteater’s (Myrmecophaga tridactyla) movement patterns and space use in São Paulo, Brazil. It is the first study to track a giant anteater with Iridium-GPS. The anteater traveled an average distance of 1326 m day^–1 with an average speed of 1.04 m min^–1. Home range by Kernel was 2.46 km² while the core area was 0.75 km², and estimates by Brownian bridge and minimum convex polygon were also provided. The anteater used shrub savanna, open savanna, and water habitats more than expected. Monitoring ended just after 10 days when the female giant anteater’s GPS was found on an illegal trail.