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The understanding of the reproductive events and the molecular mechanisms regulating fertility and infertility in humans relies heavily on the analysis of the corresponding phenotypes in mouse models. While molecular genetic approaches provide significant insight into the molecular regulation of these processes, the lack of live imaging methods that allow for detailed visualization of the mouse reproductive organs limits our investigations of dynamic events taking place during the ovulation, the fertilization and the pre-implantation stages of embryonic development. Here we introduce an in vivo three-dimensional imaging approach for visualizing the mouse oviduct and reproductive events with micro-scale spatial resolution using optical coherence tomography (OCT). This method relies on the natural tissue optical contrast and does not require the application of any contrast agents. For the first time, we present live high-resolution images of the internal structural features of the oviduct, as well as other reproductive organs and the oocytes surrounded by cumulus cells. These results provide the basis for a wide range of live dynamic studies focused on understanding fertility and infertility.OCIS codes: (110.4500) Optical coherence tomography, (170.3880) Medical and biological imaging, (170.5380) Physiology  相似文献   
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Background: Non-alcoholic fatty hepatitis (NASH) is highly prevalent, mitochondria damage is the main pathophysiological characteristic of NASH. However, treatment for mitochondria damage is rarely reported. Methods: NASH model was established in rats, the protective effects of curcumin were evaluated by histological observation; structure and function assessments of mitochondria; and apoptotic genes expression. Results: NASH rats treated with curcumin displayed relatively slight liver damage when compared with NASH livers. The average mitochondrial length and width of NASH (12.0 ± 3.2 and 5.1 ± 1.1 micrometers) were significantly longer than that of normal (6.2 ± 2.1 and 2.1 ± 1.5 micrometers) and NASH treated with curcumin (7.4 ± 1.2 and 3.2 ± 1.5 micrometers) rats. The average malondialdehyde (MDA) and 4-hydroxy nonyl alcohol (HNE) levels in liver homogenates of NASH rats (4.23 ± 0.22 and 19.23 ± 2.3 nmol/Ml) were significantly higher than these in normal (1.32 ± 0.12 and 3.52 ± 0.43 nmol/mL) and NASH treated with curcumin (1.74 ± 0.11 and 4.66 ± 0.99 nmol/mL) rats. The expression levels of CytC, Casp3 and Casp8 of the NASH livers were significantly higher than normal and NASH treated with curcumin rats livers. Conclusion: Our data demonstrated that curcumin prevents the NASH by mitochondria protection and apoptosis reduction and provided a possible novel treatment for NASH.  相似文献   
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To compare the target volume, position and matching index of the patient‐specific internal gross tumor volume (IGTV) based on three‐dimensional (3D) and four‐dimensional (4D) computed tomography (CT) images for primary esophageal cancer. Twenty‐nine patients with primary thoracic esophageal cancer underwent 3DCT and 4DCT scans during free breathing. IGTVs were constructed using three approaches: combining the gross target volumes from the 10 respiratory phases of the 4DCT dataset to produce IGTV10; IGTV2 was acquired by combining the two extreme phases; and IGTV3D was created from the 3DCT‐based gross target volume by enlarging the 95th percentile of motion in each direction measured by the 4DCT. 0.16 cm lateral (LR), 0.14 cm anteroposterior (AP) and 0.29 cm superoinferior (SI) in the upper; 0.18 cm LR, 0.10 cm AP and 0.63 cm SI in the middle; and 0.40 cm LR, 0.58 cm AP and 0.82 cm in the lower thoracic esophagus could account for 95% of respiratory‐induced tumor motion. The centroid position shift between IGTV10 and IGTV2 was all below 0.10 cm, and less than 0.20 cm between IGTV10 and IGTV3D. IGTV10 was bigger than IGTV2; the mean value of matching index for IGTV2 to IGTV10 was 0.87 ± 0.05, 0.85 ± 0.06 and 0.83 ± 0.05 for upper, middle and distal thoracic esophageal tumors, respectively, and just 0.57 ± 0.11, 0.56 ± 0.13 and 0.40 ± 0.03 between IGTV3D and IGTV10. 4DCT‐based IGTV10 is a reasonable patient‐specific IGTV for primary thoracic esophageal cancer, and IGTV2 is considered as an acceptable alternative to IGTV10. However, it seems unreasonable to use IGTV3D substitute IGTV10.  相似文献   
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The role of mitochondrial reactive oxygen species (mitoROS) in cellular function remains obscure. By synthesizing recent data, we propose here that local dynamic mitoROS in the form of "superoxide flashes" serve as "signaling ROS" rather than "homeostatic ROS", distinguishable from basal mitoROS due to constitutive leakage of the electron transfer chain (ETC). Individual superoxide flashes are 10-s mitoROS bursts that are compartmentalized to a single mitochondrion or local mitochondrial networks. As a highly-conserved universal mitochondrial activity, it occurs in intact cells, in ex vivo beating hearts, and even in living animals. Unlike basal mitoROS, superoxide flashes are ignited by transient openings of a type of mitochondrial permeability transition pore (mPTP), and their incidence is richly regulated by an array of factors that converge on either the mPTP or ETC. Emerging evidence has shown that superoxide flashes decode dietary and metabolic status or exercise, gauge oxidative stress (e.g., during reoxygenation after hypoxia or anoxia), and constitute early mitochondrial signals that initiate oxidative stress-related apoptosis in a context-dependent manner. That they make only a miniscule contribution to global ROS attests to the high efficiency of local ROS signaling. However, the exact mechanisms underlying superoxide flash formation, regulation and function remain uncertain. Future investigation is warranted to uncover the cellular logic and molecular pathways of local dynamic mitoROS signaling in heart muscle cells and many other cell types.  相似文献   
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