ABSTRACT
Polyphenol oxidases (PPOs) are type-3 copper enzymes and are involved in many biological processes. However, the potential functions of PPOs in pollination are not fully understood. In this work, we have screened 13 PPO members in Nicotiana. tabacum (named NtPPO1-13, NtPPOs) to explore their characteristics and functions in pollination. The results show that NtPPOs are closely related to PPOs in Solanaceae and share conserved domains except NtPPO4. Generally, NtPPOs are diversely expressed in different tissues and are distributed in pistil and male gametes. Specifically, NtPPO9 and NtPPO10 are highly expressed in the pistil and mature anther. In addition, the expression levels and enzyme activities of NtPPOs are increased after N. tabacum self-pollination. Knockdown of NtPPOs would affect pollen growth after pollination, and the purines and flavonoid compounds are accumulated in self-pollinated pistil. Altogether, our findings demonstrate that NtPPOs potentially play a role in the pollen tube growth after pollination through purines and flavonoid compounds, and will provide new insights into the role of PPOs in plant reproduction.
Subject(s)
Nicotiana , Pollination , Nicotiana/genetics , Pollination/genetics , Pollen Tube , Flowers , Flavonoids/metabolism , Purines/metabolismABSTRACT
OBJECTIVE: To explore the effect and mechanism of norcantharidin (NCTD) on hematopoiesis function in leucopenia model rat induced by cyclophosphamide (CTX). METHODS: Leucopenia model was replicated in SD rat with cyclophosphamide(CTX) and model animal was treated with NCTD. Peripheral blood and bone marrow tissue samples were collected from the rats in each experimental group. Peripheral white blood cells (WBC) were counted and analyzed by automatic blood cell analyzer. Histopathologic changes of the biopsied bone marrow tissues were observed by histopathological techniques. The cell cycle and apoptosis rate of bone marrow cells were detected by flow cytometry. Immunohistochemical method was applied to observe the expression of apoptosis-related proteins BCL-2 and BAX in bone marrow. RESULTS: After NCTD treatment in model rats, the WBC count of peripheral blood obviously increased, the cell structure of bone tissue significantly recovered, NCTD could promote the cell proliferation and cycle changes of bone marrow cells, inhibit the bone marrow cell apoptosis and necrosis induced with CTX, up-regulate the expression of apoptosis-related protein BCL-2 and downregulated the BAX. CONCLUSION: NCTD can stimulate the bone marrow hematopoiesis and promote recovery of peripheral white blood cell level in the leukopenia model induced by CTX, and its mechanism may be related with NCTD regulating bone marrow cell cycle and with NCTD inhibiting cell apoptosis.
Subject(s)
Hematologic Diseases , Hematopoiesis , Animals , Apoptosis , Bone Marrow , Bone Marrow Cells , Bridged Bicyclo Compounds, Heterocyclic , Cell Cycle , Cell Proliferation , Cyclophosphamide , Disease Models, Animal , Flow Cytometry , Rats , Rats, Sprague-DawleyABSTRACT
BACKGROUND: Sciatic nerve block is widely used for anesthesia and analgesia in lower limb surgery, traditional method used for sciatic nerve block is nerve stimulation guidance. Whether the use of ultrasound-guided technology can increases the success rate of sciatic nerve block and provide other benefits are not defined. This meta-analysis was aimed to clarify this issue. METHOD: We searched Pubmed, the Cochrane library and Google Scholar. A total of 10 RCTs met our inclusion criteria. The patients included underwent ultrasound-guided or nerve stimulation guidance for sciatic nerve block. We compared the success rate, vascular puncture, the time of procedure and Success rate of catheter placement. RESULTS: Ultrasound-guided technology, compared with nerve stimulation for sciatic nerve block, provided higher success rate. [RR = 1.22 95% CI: 1.04-1.42, P = 0.01], Ultrasound guidance also reduce the risk of vascular puncture. [RR = 0.13 95% CI: 0.02-0.97, P = 0.05]. However, the success rate of catheter placement [RR = 1.1095% CI: 0.93-1.29, P = 0.27] and the time of performing sciatica never block [RR = -0.17 95% CI: -1.61-1.27, P = 0.82] did not differ significantly. CONCLUSIONS: Compared to traditional nerve stimulation guidance, ultrasound guidance for sciatic nerve may improve the success rate of block and reduce the risk of vascular puncture.
