Adrenocorticotropic hormone at pathophysiological concentration modulates the proliferation and differentiation of bone cells

SummaryBackground/purposeAdrenocorticotropic hormone (ACTH) plays a vital role in maintaining the function of the hypothalamic–pituitary–adrenal axis. Recent studies have demonstrated that ACTH directly affects the proliferation and differentiation of bone cells. However, the ACTH concentrations used in these studies appear to be markedly higher than the physiological concentrations. Here, we investigated whether ACTH at pathophysiological concentration affects the proliferation and differentiation of osteoblasts and osteoclasts.Materials and methodsWe evaluated the effect of ACTH at pathophysiological concentration on osteoclasts using tartrate-resistant acid phosphatase staining and on osteoblasts using alkaline phosphatase activity assay. Additionally, we conducted reverse transcriptase-polymerase chain reaction analysis.ResultsWe found that at pathophysiological concentration, ACTH does not affect osteoblast proliferation and inhibits osteoblast differentiation. Moreover, we showed that at pathophysiological concentration, ACTH does not affect the proliferation of bone marrow macrophages, but promotes differentiation of osteoclasts and induces expression of genes involved in bone resorption.ConclusionTaken together, our findings suggest that ACTH modulates the proliferation and differentiation of bone cells in vitro at pathophysiological concentration

Multimode Quantum Correlations in Supercontinuum Pulses

Suprecontinuum (SC) light contains complex spectral noise structure and its accurate characterization is important for fundamental understanding of its physics as well as for its applications. Several experimental and theoretical noise characterizations have been performed so far. However, none of them takes into account the quantum mechanical properties. Here, we demonstrate experimental characterisation of quantum noise and its spectral correlations formed in the SC light generated from a photonic crystal fiber. Moreover, by applying an appropriate basis transformation to these correlations, we demonstrate that the SC noise amplitude can be squeezed below the shot-noise limit in some bases, even in the presence of excessively large nonlinearities.Comment: 10 pages, 5 figure

Adipocytes do not significantly contribute to plasma angiotensinogen

Recently, it has been reported that 25% of plasma angiotensinogen (Agt) is derived from fat. Meanwhile, liver-specific Agt knockout (KO) mice have markedly low plasma Agt, which may be due to reduced fat mass. To study the contribution of the fat to plasma Agt, we tested whether increasing fat mass can elevate plasma Agt and blood pressure in liver- Agt KO mice. Epididymal fat mass in liver- Agt KO mice fed a high-fat diet (HFD) was 4.1-fold larger than that in liver- Agt KO mice on a normal-fat diet (NFD). The liver- Agt KO mice on NFD were hypotensive with low levels of plasma Agt (on average, 0.11 vs 2.38 μg/ml). HFD slightly increased plasma Agt (0.17 μg/ml) without increase in blood pressure. To further increase fat mass, liver- Agt KO mice were fed HFD and simultaneously supplemented with low-dose angiotensin II and compared with control mice. Fat mass was comparable between the two groups. However, liver- Agt KO mice had uniformly low plasma Agt (0.09 vs 2.07 μg/ml) and systolic blood pressure (78±12 vs 111±6 mm Hg). In conclusion, adipocyte-derived Agt has essentially no contribution to the plasma concentration and no impact on blood pressure compared to liver-derived Agt

Effect of CO2 on Colony Development by Bifidobacterium Species▿

This report investigates the requirement for CO2 for colony formation by Bifidobacterium species in both anoxic and oxic environments. All tested Bifidobacterium species exhibited difficulty in developing colonies in an atmosphere of 100% N2 but developed well when 1% CO2 was present. In the presence of CO2, the oxygen tolerance of the tested species was not improved. In the absence of CO2, only B. boum, a microaerophilic species, could develop colonies under an N2-based 5% O2 atmosphere, indicating that while CO2 is not an essential factor for colony development, both CO2 and O2 have stimulatory effects on B. boum colony development