Cranial bone morphometric study among mouse strains

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Little is known about the molecular mechanism which regulates how the whole cranium is shaped. Mouse models currently available for genetic research include several hundreds of unique inbred strains and genetically engineered mutants. By cross comparing their genomic structures, we can elucidate the cause of any differences in the phenotype between two strains. The craniometry of subspecies, or closely related species, of mice provide a good systemic model to study the relationship between genetic variance and cranial shape evolution. The lack of a quantified framework for comparing and analyzing mouse cranial shape has been a problem. For this reason, we performed quantitative analysis of cranial shape morphology between several mouse strains. Results: This article reports on a craniometric assay of seven mouse strains: four inbred strains (C57BL/6J, BALB/cA, C3H/HeJ, and CBA/JNCr) from Mus musculus domesticus (M. m. domesticus); one closed colony strain (ICR) from M. m. domesticus; one inbred strain (MSM/Ms) from Mus musculus molossinus; and, Mus spretus as a strain from a species other than M. m. domesticus. W

Novel migrating mouse neural crest cell assay system utilizing P0-Cre/EGFP fluorescent time-lapse imaging

<p>Abstract</p> <p>Background</p> <p>Neural crest cells (NCCs) are embryonic, multipotent stem cells. Their long-range and precision-guided migration is one of their most striking characteristics. We previously reported that <it>P0-Cre/CAG-CAT-lacZ </it>double-transgenic mice showed significant lacZ expression in tissues derived from NCCs.</p> <p>Results</p> <p>In this study, by embedding a <it>P0-Cre/CAG-CAT-EGFP </it>embryo at E9.5 in collagen gel inside a culture glass slide, we were able to keep the embryo developing <it>ex vivo </it>for more than 24 hours; this development was with enough NCC fluorescent signal intensity to enable single-cell resolution analysis, with the accompanying NCC migration potential intact and with the appropriate NCC response to the extracellular signal maintained. By implantation of beads with absorbed platelet-derived growth factor-AA (PDGF-AA), we demonstrated that PDGF-AA acts as an NCC-attractant in embryos.</p> <p>We also performed assays with NCCs isolated from <it>P0-Cre/CAG-CAT-EGFP </it>embryos on culture plates. The neuromediator 5-hydroxytryptamine (5-HT) has been known to regulate NCC migration. We newly demonstrated that dopamine, in addition to 5-HT, stimulated NCC migration <it>in vitro</it>. Two NCC populations, with different axial levels of origins, showed unique distribution patterns regarding migration velocity and different dose-response patterns to both 5-HT and dopamine.</p> <p>Conclusions</p> <p>Although avian species predominated over the other species in the NCC study, our novel system should enable us to use mice to assay many different aspects of NCCs in embryos or on culture plates, such as migration, division, differentiation, and apoptosis.</p

Self-pulsation and excitability of blue-violet InGaN lasers

This article gives a review of our latest results on the self-pulsation and excitability properties of blue-violet lasers. A number of investigations of the phenomena in InGaN lasers with different designs are described. The bifurcations, which are the origin of the phenomena, are identified and the effects of the lasers parameters on device dynamics are discussed. It is shown how different laser structures can be used to control device behaviour and the dependence of self-pulsation and excitability behaviour on laser geometry is discussed. Finally, agreement between the results of numerical calculations and experimental measurements on self-pulsation is demonstrated

Outer Membrane Vesicles of Helicobacter pylori TK1402 are Involved in Biofilm Formation

<p>Abstract</p> <p>Background</p> <p><it>Helicobacter pylori </it>forms biofilms on glass surfaces at the air-liquid interface in <it>in vitro </it>batch cultures; however, biofilms of <it>H. pylori </it>have not been well characterized. In the present study, we analyzed the ability of <it>H. pylori </it>strains to form biofilms and characterized the underlying mechanisms of <it>H. pylori </it>biofilm formation.</p> <p>Results</p> <p>Strain TK1402 showed strong biofilm forming ability relative to the other strains in Brucella broth supplemented with 7% FCS. The strong biofilm forming ability of TK1402 is reflected the relative thickness of the biofilms. In addition, outer membrane vesicles (OMV) were detected within the matrix of only the TK1402 biofilms. Biofilm formation was strongly correlated with the production of OMV in this strain. We further observed that strain TK1402 did not form thick biofilms in Brucella broth supplemented with 0.2% β-cyclodextrin. However, the addition of the OMV-fraction collected from TK1402 could enhance biofilm formation.</p> <p>Conclusion</p> <p>The results suggested that OMV produced from TK1402 play an important role in biofilm formation in strain TK1402.</p

Self-pulsation in an InGaN laser - theory and experiment -

Room-temperature operation of self-pulsating InGaN lasers was obtained at a wavelength of 395 nm. The laser structure consists of a multiquantum-well InGaN active layer and a p-type InGaN single-quantum-well saturable absorber. The frequency range of the self-pulsation was from 1.6 to 2.9 GHz. The experimental results were well explained with our theoretical analysis. We found that features of the saturable absorber strongly affect the self-pulsation. Influence of device and material parameters on the laser dynamics was also investigated

Gastric Cancer with a Very High Serum CA 19-9 Level

Carbohydrate antigen 19-9 (CA 19-9) is a sensitive marker for pancreatic and hepatobiliary malignancies. The highest frequency of elevated serum CA 19-9 levels is found among patients with pancreatic cancer. CA 19-9 has recently been demonstrated to be a marker of digestive tract malignancies. We report the case of a patient with a gastric cancer and a very high serum CA 19-9 level. During laparotomy, a large mass was found in the antrum. A distal gastrectomy with D2 dissection of the lymph nodes was performed. Histological examination, including immunohistochemistry, revealed an adenocarcinoma of the stomach producing CA 19-9. To the best of our knowledge, no patient with an extremely high serum CA 19-9 level resulting from a gastric adenocarcinoma has been reported previously

Low magnetic field promotes recombinant human BMP-2-induced bone formation and influences orientation of trabeculae and bone marrow-derived stromal cells

Effects of high magnetic fields [MFs, ≥ 1 T (T)] on osteoblastic differentiation and the orientation of cells or matrix proteins have been reported. However, the effect of low MFs (< 1 T) on the orientation of bone formation is not well known. This study was performed to verify the effects of low MFs on osteoblastic differentiation, bone formation, and orientation of both cells and newly formed bone. An apparatus was prepared with two magnets (190 mT) aligned in parallel to generate a parallel MF. In vitro, bone marrow-derived stromal cells of rats were used to assess the effects of low MFs on cell orientation, osteoblastic differentiation, and mineralization. A bone morphogenetic protein (BMP)-2-induced ectopic bone model was used to elucidate the effect of low MFs on microstructural indices, trabecula orientation, and the apatite c-axis orientation of newly formed bone. Low MFs resulted in an increased ratio of cells oriented perpendicular to the direction of the MF and promoted osteoblastic differentiation in vitro. Moreover, in vivo analysis demonstrated that low MFs promoted bone formation and changed the orientation of trabeculae and apatite crystal in a direction perpendicular to the MF. These changes led to an increase in the mechanical strength of rhBMP-2-induced bone. These results suggest that the application of low MFs has potential to facilitate the regeneration of bone with sufficient mechanical strength by controlling the orientation of newly formed bone.Okada R., Yamato K., Kawakami M., et al. Low magnetic field promotes recombinant human BMP-2-induced bone formation and influences orientation of trabeculae and bone marrow-derived stromal cells. Bone Reports, 14, 100757. https://doi.org/10.1016/j.bonr.2021.100757

Effects of continuous passive motion on the expression of membrane type 1-matrix metalloproteinase in rat immobilized muscles

We examined the effects of continuous passive motion（ CPM） on membrane type 1-matrix metalloproteinase（ MT1-MMP） expression in rat immobilized muscles. Eight-week-old male Wister rats were used for each of two trials, one with 2 weeks, and another one with 4 weeks of immobilization with/without CPM. In each trial, rats were immobilized（ immobilization group）, and immobilized and simultaneously given CPM （CPM group）. The soleus muscle of each rat was evaluated by gelatin zymography, western blotting and reverse transcription-polymerase chain reaction（ RT-PCR）. Gelatin zymography revealed a greater level of gelatinase activity in the extract of the muscles of the immobilization group than in those of the control and CPM group. The expressions of matrix metalloproteinase 2 （MMP-2） and MT1-MMP mRNA in the muscle extract of the immobilization group were also greater than those in the control and CPM group. Our results suggested that joint immobilization induces expression of MT1-MMP, a cleavage enzyme of MMP-2 in muscles, resulting in muscular degeneration, and that CPM can prevent these changes