First data on the age,growth processes,and otoliths of snub-nosed spiny eel <Emphasis Type="Italic">Notacanthus chemnitzii</Emphasis> (Notacanthidae)

This is the first work on the age, developmental stages, and otoliths of snub-nosed spiny eel Notacanthus chemnitzii (Notacanthidae), a rare fish species inhabiting the waters of southwestern Greenland. The mean age of 14 studied fishes (with a length of 36–104 cm and a mass of 74–3834 g) varied in the range from 11 to 26 years. Since the duration of leptocephalus stage is unknown, the real age can be greater. The length of snub-nosed spiny eel can reach 122 cm; thus, its maximal age can be more than 30 years. The minimal length of mature females was 55 cm (18 years); the minimal length of mature males was 66 cm (14 years).     

The anabolic action of intermittent parathyroid hormone on cortical bone depends partly on its ability to induce nitric oxide‐mediated vasorelaxation in BALB/c mice

There is strong evidence that vasodilatory nitric oxide (NO) donors have anabolic effects on bone in humans. Parathyroid hormone (PTH), the only osteoanabolic drug currently approved, is also a vasodilator. We investigated whether the NO synthase inhibitor L‐NAME might alter the effect of PTH on bone by blocking its vasodilatory effect. BALB/c mice received 28 daily injections of PTH[1–34] (80 µg/kg/day) or L‐NAME (30 mg/kg/day), alone or in combination. Hindlimb blood perfusion was measured by laser Doppler imaging. Bone architecture, turnover and mechanical properties in the femur were analysed respectively by micro‐CT, histomorphometry and three‐point bending. PTH increased hindlimb blood flow by >30% within 10 min of injection (P < 0.001). Co‐treatment with L‐NAME blocked the action of PTH on blood flow, whereas L‐NAME alone had no effect. PTH treatment increased femoral cortical bone volume and formation rate by 20% and 110%, respectively (P < 0.001). PTH had no effect on trabecular bone volume in the femoral metaphysis although trabecular thickness and number were increased and decreased by 25%, respectively. Co‐treatment with L‐NAME restricted the PTH‐stimulated increase in cortical bone formation but had no clear‐cut effects in trabecular bone. Co‐treatment with L‐NAME did not affect the mechanical strength in femurs induced by iPTH. These results suggest that NO‐mediated vasorelaxation plays partly a role in the anabolic action of PTH on cortical bone. © 2016 The Authors. Cell Biochemistry and Function published by John Wiley & Sons, Ltd.     

Otolith shape lends support to the sensory drive hypothesis in rockfishes

The sensory drive hypothesis proposes that environmental factors affect both signalling dynamics and the evolution of signals and receivers. Sound detection and equilibrium in marine fishes are senses dependent on the sagittae otoliths, whose morphological variability appears intrinsically linked to the environment. The aim of this study was to understand if and which environmental factors could be conditioning the evolution of this sensory structure, therefore lending support to the sensory drive hypothesis. Thus, we analysed the otolith shape of 42 rockfish species (Sebastes spp.) to test the potential associations with the phylogeny, biological (age), ecological (feeding habit and depth distribution) and biogeographical factors. The results showed strong differences in the otolith shapes of some species, noticeably influenced by ecological and biogeographical factors. Moreover, otolith shape was clearly conditioned by phylogeny, but with a strong environmental effect, cautioning about the use of this structure for the systematics of rockfishes or other marine fishes. However, our most relevant finding is that the data supported the sensory drive hypothesis as a force promoting the radiation of the genus Sebastes. This hypothesis holds that adaptive divergence in communication has significant influence relative to other life history traits. It has already been established in Sebastes for visual characters and organs; our results showed that it applies to otolith transformations as well (despite the clear influence of feeding and depth), expanding the scope of the hypothesis to other sensory structures.     

Repeated immunostaining of the same tissue section using alkaline phosphatase as a reporter

One can determine the best dilution of a primary antibody for immunohistochemistry that uses horseradish peroxidase conjugated to a secondary antibody by testing increasing concentrations sequentially on the same tissue section. When the same tissue section is incubated repeatedly with increasing concentrations of primary antibodies to epithelial membrane antigen, smooth muscle α-actin, or vimentin using alkaline phosphatase conjugated to a secondary antibody as the reporter, the best staining was obtained with a less concentrated primary antibody than was optimal for a single staining test. The best concentration of primary antibody for single run staining using an alkaline phosphatase reporting system is usually four times the best concentration for staining with multiple runs. The optimal concentration can be determined by denaturing the residual alkaline phosphatase and extracting residual stain by incubating the section in 4:1 diglyme:phosphate buffered saline for 20 min at 80^o C between tests of primary antibody concentrations. I tested the method for four chromogens from one supplier and one chromogen from a different supplier.     

Marine biology of the pacific lamprey Entosphenus tridentatus

Reviews in Fish Biology and Fisheries - Pacific lamprey Entosphenus tridentatus has an anadromous life cycle that begins with larvae that filter-feed in freshwater, followed by transformation into...     

A Ca2+-Binding Protein that Regulates the Lifetime of the Transducin Active State

Biophysics - Abstract—It has been previously shown in the study of the kinetic behavior of cGMP-specific phosphodiesterase in preparations of the outer segments of bovine retinal rods, which...     

First Mass Capture of Black Snake Mackerel Nealotus tripes (Gempylidae)

Journal of Ichthyology - This article documents the first mass capture (over 300 individuals per catch) of black snake mackerel Nealotus tripes (Gempylidae) in the open part of the northwestern...     

Erratum to: Transoceanic Migration of Pacific Lamprey,Entosphenus tridentatus

Journal of Ichthyology -     

Histostructure of the Locomotor Apparatus in the Three Deep-Water Species of Lanternfishes (Myctophidae): Myctophum punctatum,Notoscopelus kroyeri,and Lampanyctus macdonaldi

Journal of Ichthyology - The morphological and functional characteristics of the somatic musculature’s histological structure have been studied for three species of deep-sea fish from the...