91 research outputs found
Efficient callus induction and indirect plant regeneration from various tissues of Jatropha curcas
The Jatropha curcas is considered as an important energy plant due to the fact that its seed contains high oil content. Nowadays focus is being placed on J. curcas callus induction and plant regeneration. In this study, explants epicotyl, hypocotyl, petiole and cotyledon of 8-day-old seedlings of J. curcas were utilized for callus induction on media supplied with 1 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D), naphthyl acetic acid (NAA) or indolebutyric acid (IBA) and 0.1 mg/L kinetin (Kin), and the results demonstrated that the combination of 1 mg/L NAA and 0.1 mg/L Kin was the best medium for callus induction and growth. In addition, induced calli were transferred to regeneration medium containing different combination of auxins and cytokinins, and the data showed that the medium containing 1 mg/L thidiazuron (TDZ) and 1 mg/L Kin combined with 0.1 mg/L IBA was propitious to plant regeneration compared with other combinations.Keywords: Callus induction, indolebutyric acid, Jatropha curcas, kinetin, naphthyl acetic acid, plant regeneration, thidiazuro
The First Sinomastodon (Gomphotheriidae, Proboscidea) Skull From the Quaternary in China
The first Sinomastodon (Gomphotheriidae, Proboscidea) skull of the Early Pleistocene, collected from the Renzidong Cave deposits in Anhui Province, Eastern China, is described here as S. jiangnanensis sp. nov. As the only brevirostrine trilophodont gomphotheriid known from the Old World, Sinomastodon was mainly indigenous to China from the Early Pliocene to the Pleistocene. Compared with a few single Pleistocene teeth previously found in China, S. jiangnanensis sp. nov. is represented by a relatively complete skull, mandible and dentition, which is the first discovery of a Quaternary Sinomastodon skull from China. With a brevirostrine, elephant-like skull, no lower tusks, and simple bunodont and trilophodont intermediate molars, the new species is morphologically distinct from other gomphotheres and should belong to the genus Sinomastodon. The new species is more progressive than S. hanjiangensis and the Pliocene type species S. intermedius in its skull and mandible morphology, but is evidently more primitive than the Pleistocene S. yangziensis in its molar morphology. The faunal analysis suggests that the emergence of S. jiangnanensis sp. nov. in Jiangnan area and its southward migration may have been related to a cooling event at the beginning of the Quaternary in Eastern China
The First Sinomastodon (Gomphotheriidae, Proboscidea) Skull From the Quaternary in China
The first Sinomastodon (Gomphotheriidae, Proboscidea) skull of the Early Pleistocene, collected from the Renzidong Cave deposits in Anhui Province, Eastern China, is described here as S. jiangnanensis sp. nov. As the only brevirostrine trilophodont gomphotheriid known from the Old World, Sinomastodon was mainly indigenous to China from the Early Pliocene to the Pleistocene. Compared with a few single Pleistocene teeth previously found in China, S. jiangnanensis sp. nov. is represented by a relatively complete skull, mandible and dentition, which is the first discovery of a Quaternary Sinomastodon skull from China. With a brevirostrine, elephant-like skull, no lower tusks, and simple bunodont and trilophodont intermediate molars, the new species is morphologically distinct from other gomphotheres and should belong to the genus Sinomastodon. The new species is more progressive than S. hanjiangensis and the Pliocene type species S. intermedius in its skull and mandible morphology, but is evidently more primitive than the Pleistocene S. yangziensis in its molar morphology. The faunal analysis suggests that the emergence of S. jiangnanensis sp. nov. in Jiangnan area and its southward migration may have been related to a cooling event at the beginning of the Quaternary in Eastern China
Nonlinear optical radiation of a lithium niobate microcavity
The nonlinear optical radiation of an integrated lithium niobate microcavity
is demonstrated, which has been neglected in previous studies of nonlinear
photonic devices. We find that the nonlinear coupling between confined optical
modes on the chip and continuum modes in free space can be greatly enhanced on
the platform of integrated microcavity, with feasible relaxation of the
phase-matching condition. With an infrared pump laser, we observe the vertical
radiation of second-harmonic wave at the visible band, which indicates a robust
phase-matching-free chip-to-free-space frequency converter and also unveils an
extra energy dissipation channel for integrated devices. Such an unexpected
coherent nonlinear interaction between the free-space beam and the confined
mode is also validated by the different frequency generation. Furthermore,
based on the phase-matching-free nature of the nonlinear radiation, we build an
integrated atomic gas sensor to characterize Rb isotopes with a single telecom
laser. The unveiled mechanism of nonlinear optical radiation is universal for
all dielectric photonic integrated devices, and provides a simple and robust
chip-to-free-space as well as visible-to-telecom interface.Comment: 7 Pages, 4 figure
Retinoic Acid and Arsenic for Treating Acute Promyelocytic Leukemia
What were the critical steps in the development of ATRA and arsenic as treatments for APL? Researchers in Shanghai tell the story and look to the futur
Overexpression and Small Molecule-Triggered Downregulation of CIP2A in Lung Cancer
Lung cancer is the leading cause of cancer deaths worldwide, with a five-year overall survival rate of only 15%. Cancerous inhibitor of PP2A (CIP2A) is a human oncoprotein inhibiting PP2A in many human malignancies. However, whether CIP2A can be a new drug target for lung cancer is largely unclear.Normal and malignant lung tissues were derived from 60 lung cancer patients from southern China. RT-PCR, Western blotting and immunohistochemistry were used to evaluate the expression of CIP2A. We found that among the 60 patients, CIP2A was undetectable or very low in paratumor normal tissues, but was dramatically elevated in tumor samples in 38 (63.3%) patients. CIP2A overexpression was associated with cigarette smoking. Silencing CIP2A by siRNA inhibited the proliferation and clonogenic activity of lung cancer cells. Intriguingly, we found a natural compound, rabdocoetsin B which is extracted from a Traditional Chinese Medicinal herb Rabdosia coetsa, could induce down-regulation of CIP2A and inactivation of Akt pathway, and inhibit proliferation and induce apoptosis in a variety of lung cancer cells.Our findings strongly indicate that CIP2A could be an effective target for lung cancer drug development, and the therapeutic potentials of CIP2A-targeting agents warrant further investigation
Long Non-coding RNAs and Their Roles in Non-small-cell Lung Cancer
As a leading cause of cancer deaths worldwide, lung cancer is a collection of diseases with diverse etiologies which can be broadly classified into small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). Lung cancer is characterized by genomic and epigenomic alterations; however, mechanisms underlying lung tumorigenesis remain to be elucidated. Long non-coding RNAs (lncRNAs) are a group of non-coding RNAs that consist of ⩾200 nucleotides but possess low or no protein-coding potential. Accumulating evidence indicates that abnormal expression of lncRNAs is associated with tumorigenesis of various cancers, including lung cancer, through multiple biological mechanisms involving epigenetic, transcriptional, and post-transcriptional alterations. In this review, we highlight the expression and roles of lncRNAs in NSCLC and discuss their potential clinical applications as diagnostic or prognostic biomarkers, as well as therapeutic targets
Death-associated protein kinase 1 correlates with podocyte apoptosis and renal damage and can be mediated by miR-361
Background. Herein, we aimed to determine
whether DAPK1 and its post-transcriptional regulator
miR-361 were implicated in high glucose (HG)-induced
podocyte injury and renal damage in db/db mice.
Materials and methods. Podocytes were incubated
with normal glucose (NG; 5 mM) or HG (30 mM).
Podocyte apoptosis was evaluated using TUNEL
staining. Lentiviral-delivered specific short hairpin RNA
(shRNA) was designed to silence DAPK1 expression in
podocytes. miR-361 agomir was administrated by tail
intravenous injection in db/db diabetic mice to
investigate the renoprotection of miR-361 in vivo.
Results. Exposure of podocytes to HG led to a
significant increase in DAPK1 mRNA and protein levels
and a decrease in miR-361 expression levels.
Knockdown of DAPK1 attenuated HG-triggered growth
inhibition, apoptosis, DNA damage and cell membrane
damage in podocytes. Mechanically, DAPK1 was a
direct target of miR-361. Transfection with miR-361
mimics into podocytes resulted in a significant decrease
in the DAPK1 protein expression level. In addition, HGinduced the up-regulation of the DAPK1 protein
expression level in podocytes was restrained by miR-361
mimics transfection. Intriguingly, overexpression of
DAPK1 in HG-stimulated podocytes muted miR-361-
mediated cytoprotection, including anti-apoptosis,
resistance to DNA and membrane damage. In vivo,
overexpression of miR-361 protected against
hyperglycemia-induced podocyte loss, tubular atrophy
and interstitial fibrosis in the kidney of db/db mice.
Moreover, overexpression of miR-361 inhibited the
protein expression of DAPK1 in the kidney of db/db
mice.
Conclusion. Our research presented a novel
mechanism of HG-induced podocyte damage or renal
lesion, supporting the miR-361/DAPK1 signaling
pathway that could be used as a potential therapeutic
target for the treatment of DN
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