In vitro propagation of katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc), an endangered plant in China

Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) is a long-lived, deciduous, wind-pollinated tree with dimorphic leaves. It is valued as an ornamental or a shade tree for landscape and a commercially valuable tree. Conventional propagation through seeds and cutting is not sufficient to satisfy the progressive demand. There is an exigent need to develop protocols for rapid propagation of katsura trees. This study reports an in vitro propogation of the tree. The work focused on assessing the effects of basal medium, plant growth regulators (PGRs) combination on shoot and root proliferation. Nodal sections of young shoots were used as explants. Shoot initiation, and shoot and root proliferation were carried out on basal medium and PGRs combination. The optimal response of shoot initiation was observed in woody plant medium (WPM) supplemented with 1.0 mg L−1BA and 0.01 mg L−1IBA (indole-3-butyric acid) and the percentage of shoot initiation was up to 91.66%. For proliferation of micropropagated shoots, three orthogonal designs were carried out. The result shows that the highest proliferation coefficient (4.83) was obtained in the medium containing 1.0 mg L−1 BA and 0.05 mg L−1 NAA. With the application of benzyladenine (BA) and naphthalene acetic acid (NAA), emerald green and vigorous shoots were observed. Shoots about 2.0 cm long with 4 to 6 leaves were excised and transferred to root propagation media. When the concentration of NAA was 0.5 mg L−1, the rooting percentage, mean number and mean length of roots were the highest, reaching 75% and 3.1 and 2.1 cm respectively. This efficient plant regeneration system would be helpful for genetic improvement through future conservation and biotechnology research.Keywords: Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc), shoot initiation, shoot propagation, root propagatio

New nematode species from the continental slope of New Zealand (Chromadorea, Microlaimida, and Chromadorida), and unexpected placement of the genus Molgolaimus Ditlevsen, 1921

Abstract(#br)The current nematode classification comprises three primarily marine basal Chromadorean orders: the Microlaimida Leduc et al., 2018; Desmodorida De Coninck, 1965; and Chromadorida Chitwood, 1933. The phylogenetic placement of several taxa within these orders, however, is unclear due to the paucity of taxonomically informative morphological characters for high-level classification and is yet to be tested by molecular phylogenetic analyses due to the absence of molecular sequences. Here, we describe Molgolaimus kaikouraensis sp. nov. and Aponema pseudotorosum sp. nov. from the continental slope of New Zealand and investigate phylogenetic relationships of these species and that of the rare desmodorid genera Onepunema and Pseudonchus , using SSU phylogenetic analyses for the..

Biofouling characteristics in Xinghua Bay of Fujian, China

Biofouling is one of the main factors affecting the efficiency and safety of cooling water systems in coastal nuclear power plants. Understanding the population dynamics, succession rules and cumulative effects of major fouling organisms is the basis for targeted prevention and control. A 1-year simulated concrete panel test was conducted from December 2020 to November 2021 in Xinghua Bay, China. A total of 78 species of fouling organisms were recorded by combining the monthly, seasonal, semiannual, annual and monthly cumulative panels, and the community composition was dominated by nearshore warm-water species, making for a typical subtropical inner bay-type community. The fouling organisms had a peak attachment period from June to October. Significantly more attachment was observed during summer (from June to August) than during the other three seasons. The attachment amount in the second half-year (from June to November) was much higher than that in the first half-year (from December to May). The attachment thickness, density, and biomass of the bottom summer panels reached 20 cm, 105,150 ind./m2, and 19,274.50 g/m2, respectively, while those of the bottom annual panels were 40 cm, 27,300 ind./m2, and 17,762.50 g/m2, respectively. The dominant fouling organisms with calcified shells mainly included Amphibalanus reticulatus and Pernaviridis. These species had high attachment amounts,could accumulate attachments for a long time, and even might cause secondary blockage, making them the most detrimental to the safety of a cooling system. Moreover,the seasonal upward growth of hydroids and bryozoans can also significantly reduce the efficiency of cooling water intake. We suggest that targeted prevention and control should be carried out according to the larval attachment period of different dominant groups of fouling organisms during June-October, which can greatly improve the prevention and control efficiency. Strengthening the research on the biological cycle phenomenon of the main species and their main environmental impact factors, and establishing a scientific and effective early-warning model are the governance direction of formulating and implementing scientific pollution prevention and control in the future

Three new free-living marine nematode species of Dorylaimopsis (Nematoda Araeolaimida: Comesomatidae) from the South China Sea and the Chukchi Sea

Fu, Sujing, Leduc, Daniel, Rao, Yiyong, Cai, Lizhe (2019): Three new free-living marine nematode species of Dorylaimopsis (Nematoda Araeolaimida: Comesomatidae) from the South China Sea and the Chukchi Sea. Zootaxa 4608 (3): 433-450, DOI: 10.11646/zootaxa.4608.3.

Distribution of meiofaunal abundance in relation to environmental factors in Beibu Gulf, South China Sea

State Oceanic Administration of ChinaThis study aims to explore the distribution of meiofaunal abundance in relation to environmental factors in the Beibu Gulf, a natural semi-enclosed part of the South China Sea, surrounded by China and Vietnam. Meiofauna and ten benthic environmental factors were determined at 27 sampling stations in the Beibu Gulf in four surveys during 2006-2007. The results show a clear geographical trend in meiofaunal abundance, water depth, salinity and clay content. The meiofaunal abundance and the clay content decreased, whereas the water depth and the salinity increased from the north to the south of the Gulf. The percentage of meiofaunal abundance in the 0-2 cm layer increased, whereas in the 2-5 cm and 5-10 cm layers it decreased from the north to the south of the Gulf. Correlation analysis show significant negative correlations between meiofaunal abundance and water depth, benthic temperature, salinity and pH, but significant positive correlations between meiofaunal abundance and dissolved oxygen, chlorophyll a and clay content

Targeting ectodysplasin promotor by CRISPR/dCas9-effector effectively induces the reprogramming of human bone marrow-derived mesenchymal stem cells into sweat gland-like cells

Abstract Background Patients with a deep burn injury are characterized by losing the function of perspiration and being unable to regenerate the sweat glands. Because of their easy accession, multipotency, and lower immunogenicity, bone marrow-derived mesenchymal stem cells (BM-MSCs) represent as an ideal biological source for cell therapy. The aim of this study was to identify whether targeting the promotor of ectodysplasin (EDA) by CRISPR/dCas9-effector (dCas9-E) could induce the BM-MSCs to differentiate into sweat gland-like cells (SGCs). Methods Activation of EDA transcription in BM-MSCs was attained by transfection of naive BM-MSCs with the lenti-CRISPR/dCas9-effector and single-guide RNAs (sgRNAs). The impact of dCas9-E BM-MSCs on the formation of SGCs and repair of burn injury was identified and evaluated both in vitro and in a mouse model. Results After transfection with sgRNA-guided dCas9-E, the BM-MSCs acquired significantly higher transcription and expression of EDA by doxycycline (Dox) induction. Intriguingly, the specific markers (CEA, CK7, CK14, and CK19) of sweat glands were also positive in the transfected BM-MSCs, suggesting that EDA plays a critical role in promoting BM-MSC differentiation into sweat glands. Furthermore, when the dCas9-E BM-MSCs with Dox induction were implanted into a wound in a laboratory animal model, iodine-starch perspiration tests revealed that the treated paws were positive for perspiration, while the paws treated with saline showed a negative manifestation. For the regulatory mechanism, the expression of downstream genes of NF-κB (Shh and cyclin D1) was also enhanced accordingly. Conclusions These results suggest that EDA is a pivotal factor for sweat gland regeneration from BM-MSCs and may also offer a new approach for destroyed sweat glands and extensive deep burns

[Médailles de Silésie monnaies-antiques, moyen-âge et modernes, Russie, Alsace etc...]

[Vente. Numismatique. 1898-10-26. Frankfort][Collection. Numismatique. Pniower, Georges. 1898]Avec mode text

Bone Marrow-Derived Mesenchymal Stem Cells Promoted Cutaneous Wound Healing by Regulating Keratinocyte Migration via β₂‑Adrenergic Receptor Signaling

Mesenchymal stem cells (MSCs) play an important role in cutaneous wound healing; however, the functional mechanisms involved in the healing process are poorly understood. A series of studies indicate that keratinocytes that migrate into the wound bed rely on an epithelial-mesenchymal transition (EMT)-like process to initiate re-epithelialization. We therefore examined whether bone marrow-derived MSCs (BMSCs) could affect biological behavior and induce EMT-like characteristics in the human epidermal keratinocytes (HEKs) and in the immortalized human keratinocyte cell line HaCaT cells, and we investigated the signaling pathways of BMSC-mediated phenotypic changes. By assessing the expression of EMT-related markers including E-cadherin, α-SMA, and Snail family transcription factors by β₂-adrenergic receptor (β₂-AR) blockage using ICI-118,551, a β₂-AR selective antagonist, or β₂-AR small interfering RNA (siRNA), we showed an involvement of β₂-AR signaling in the induction of EMT-like alterations in human keratinocytes in vitro. β₂-AR signaling also affected collective and individual cell migration in human keratinocyte cell lines, which was attenuated by administration of ICI-118,551. Treating the cells with BMSC-conditioned media (BMSC-CM) not only recapitulated the effect of isoproterenol (ISO) on cell migration but also induced the expression of β₂-AR and a panel of proteins associated with mesenchymal phenotype in HEKs and HaCaT cells. Similarly, a blockade of the β₂-AR by either ICI-118,551 or β₂-AR siRNAs reversed both responses of the epidermal keratinocyte cell lines relative to BMSC-CM exposure. These results were further verified in our vivo findings and indicated that the exogenous application of MSCs promoted cutaneous wound healing and endowed the keratinocytes surrounding the wound area with an increased migratory phenotype through activation of β₂-AR signaling. Our findings suggest a biochemical mechanism underlying the function of MSCs in wound re-epithelization, which provides a reliable theoretical basis for the wide application of MSCs in the treatment of chronic wounds