Hormonal facilitation in the release of sperm from the spermatheca of the red-spotted newt

Summary Several neurotransmitters and hormones with potential to trigger a simultaneous contraction of the oviducts and the spermathecal myoepithelium were examined. Saline (0.05 ml), or 0.05 ml saline plus acetylcholine (9 mg), norepinephrine (50 g), arginine-vasotocin (25 units), prostaglandin F₂(3g) were injected into the spermathecal region of female newts (n=24 per group). The numbers of sperm present in the cloacae of prostaglandin-injected animals (107±30 SEM) were significantly greater than the numbers detected in saline (27±5 SEM) and in uninjected (14±3 SEM) controls. Smaller and less consistent increases in the numbers of sperm were detected in the vasotocin- and norepinephrine-injected groups. Study of sections from ovulating female newts failed to produce evidence that pressure from the passage of ova through the posterior portion of the oviduct forced sperm from the spermatheca. Observations indicate an active role for the spermathecal myoepithelium in the discharge of stored sperm and of a role for prostaglandin F₂ in triggering that discharge.     

Immobilization of cross-linked In-doped Mo(O,S)2 on cellulose nanofiber for effective organic-compound degradation under visible light illumination

Relatively small amounts of In-doped Mo(O,S)₂ (IMS) catalysts (10%, 20%, and 30%) were deposited on cellulose nanofiber (CNF) by cross-linking them with functional groups of siloxane and epoxy to form CNF-IMS hybrid composites. The as-prepared hybrid composites were characterized and tested their performances toward the photo degradations of cationic (MB and RhB) and anionic (MO) dyes. As indium was doped into Mo(O,S)₂ lattice to form solid-solution, the charge transfer and photocarrier separation during the catalytic reaction were simultaneously enhanced as probed with electrochemical impedance spectroscopy and photoluminescence measurements, respectively. To ensure the catalyst on CNF was well deposited and recyclable, the hybrid composite was evaluated with a reusability experiment to show the stability performance in degrading organic dyes. It was found the environmentally friendly CNF-IMS hybrid composite was relatively stable during the reusability experiment, indicating no catalyst powder was leached out during the photocatalytic reaction. The photoreaction mechanism was convinced by radical-scavenging experiments to show that hydroxyl and superoxide played essential roles for the organic dye degradations in visible-light illuminated conditions. The cross-linked organic/inorganic hybrid catalyst showed a prospective visible light active material not only to solve the environmental issue due to the leaching of nanoparticles but also to lower the post-treatment/recycling cost of photocatalyst in industrial application.     

Natural history of mesenchymal stem cells,from vessel walls to culture vessels

Mesenchymal stem/stromal cells (MSCs) can regenerate tissues by direct differentiation or indirectly by stimulating angiogenesis, limiting inflammation, and recruiting tissue-specific progenitor cells. MSCs emerge and multiply in long-term cultures of total cells from the bone marrow or multiple other organs. Such a derivation in vitro is simple and convenient, hence popular, but has long precluded understanding of the native identity, tissue distribution, frequency, and natural role of MSCs, which have been defined and validated exclusively in terms of surface marker expression and developmental potential in culture into bone, cartilage, and fat. Such simple, widely accepted criteria uniformly typify MSCs, even though some differences in potential exist, depending on tissue sources. Combined immunohistochemistry, flow cytometry, and cell culture have allowed tracking the artifactual cultured mesenchymal stem/stromal cells back to perivascular anatomical regions. Presently, both pericytes enveloping microvessels and adventitial cells surrounding larger arteries and veins have been described as possible MSC forerunners. While such a vascular association would explain why MSCs have been isolated from virtually all tissues tested, the origin of the MSCs grown from umbilical cord blood remains unknown. In fact, most aspects of the biology of perivascular MSCs are still obscure, from the emergence of these cells in the embryo to the molecular control of their activity in adult tissues. Such dark areas have not compromised intents to use these cells in clinical settings though, in which purified perivascular cells already exhibit decisive advantages over conventional MSCs, including purity, thorough characterization and, principally, total independence from in vitro culture. A growing body of experimental data is currently paving the way to the medical usage of autologous sorted perivascular cells for indications in which MSCs have been previously contemplated or actually used, such as bone regeneration and cardiovascular tissue repair.     

Magnetic-field-induced charge-stripe order in the high-temperature superconductor YBa2Cu3Oy

Electronic charges introduced in copper-oxide (CuO(2)) planes generate high-transition-temperature (T(c)) superconductivity but, under special circumstances, they can also order into filaments called stripes. Whether an underlying tendency towards charge order is present in all copper oxides and whether this has any relationship with superconductivity are, however, two highly controversial issues. To uncover underlying electronic order, magnetic fields strong enough to destabilize superconductivity can be used. Such experiments, including quantum oscillations in YBa(2)Cu(3)O(y) (an extremely clean copper oxide in which charge order has not until now been observed) have suggested that superconductivity competes with spin, rather than charge, order. Here we report nuclear magnetic resonance measurements showing that high magnetic fields actually induce charge order, without spin order, in the CuO(2) planes of YBa(2)Cu(3)O(y). The observed static, unidirectional, modulation of the charge density breaks translational symmetry, thus explaining quantum oscillation results, and we argue that it is most probably the same 4a-periodic modulation as in stripe-ordered copper oxides. That it develops only when superconductivity fades away and near the same 1/8 hole doping as in La(2-x)Ba(x)CuO(4) (ref.?1) suggests that charge order, although visibly pinned by CuO chains in YBa(2)Cu(3)O(y), is an intrinsic propensity of the superconducting planes of high-T(c) copper oxides.     

C-terminal truncations in human 3'-5' DNA exonuclease TREX1 cause autosomal dominant retinal vasculopathy with cerebral leukodystrophy

Autosomal dominant retinal vasculopathy with cerebral leukodystrophy is a microvascular endotheliopathy with middle-age onset. In nine families, we identified heterozygous C-terminal frameshift mutations in TREX1, which encodes a 3'-5' exonuclease. These truncated proteins retain exonuclease activity but lose normal perinuclear localization. These data have implications for the maintenance of vascular integrity in the degenerative cerebral microangiopathies leading to stroke and dementias.     

Isoelectric focusing of mosquito esterases in the presence of Triton X-100

Summary Triton X-100 improves nonspecific esterase solubilization from mosquito samples and also leads to increased resolution in an isoelectric focusing electrophoresis.Acknowledgments. This research was supported by a US Army contract/grant DAMD 17-77-C-7018, US Army Medical Research and Development Command, Washington, DC and by the Office of Naval Research.