Optimization of factors affecting the rooting of pine wilt disease resistant Masson pine (Pinus massoniana) stem cuttings.

Pine wilt disease (PWD) is a devastating disease affecting trees belonging to the genus Pinus. To control the spread of PWD in the Masson pine forest in China, PWD resistant Masson pine clones have been selected by the Anhui Academy of Forestry. However, because Masson pine is a difficult-to-root species, producing seedlings is challenging, especially from trees older than 5 years of age, which impedes the application of PWD resistant clones. In this study, we investigated the factors affecting rooting of PWD resistant clones and established a cheap, reliable, and simple method that promotes rooting. We tested the effects of three management methods, four substrates, two cutting materials, two cutting treatments, and three collection times on the rooting of cuttings obtained from 9-year-old PWD resistant clones. Rooting was observed only in stem cuttings treated with the full-light automatic spray management method. Additionally, stem cuttings showed a significantly higher rooting rate and root quality than needles cuttings. Compared with other substrates, stem cuttings planted in perlite produced the longest adventitious root and the highest total root length and lateral root number. Moreover, stem cuttings of PWD resistant clones collected in May showed a significantly higher rooting rate and root quality than those collected in June and July. Moreover, stem cuttings prepared with a horizontal cut while retaining the needles showed significantly higher rooting rate and root quality than those prepared with a diagonal cut while partly removing the needles. This study promotes the reproduction of seedlings of PWD-resistant Masson pine clones which helps control the spread of PWD, meanwhile, provides a technical reference for the propagation of mature pine trees via cuttings.

CircZFR serves as a prognostic marker to promote bladder cancer progression by regulating miR-377/ZEB2 signaling.

Circular RNAs (circRNAs) have been identified as crucial regulators of gene expression in human cancer biology. CircZFR is a novel identified circRNA and its effect in bladder cancer remains unclearly. In the present study, we aimed to investigate the role of circZFR in the progression of bladder cancer. First, we demonstrated that the expression of circZFR was higher in bladder cancer tissues and cells compared with adjacent non-tumor tissues and normal bladder epithelial cells. And higher circZFR levels were positively correlated with bladder cancer patients' pathological T stage, grade, lymphatic metastasis, recurrence, progression-free survival (PFS) and overall survival (OS). Functionally, knockdown of circZFR could significantly prohibit cell growth, migration and invasion, arrest cell cycle as well as promote apoptosis of bladder cancer cells in vitro study. Mechanistically, we observed that circZFR could directly bind to miR-377 as sponge to promote ZEB2 expression in bladder cancer cells. In addition, rescue assays demonstrated that restoration of ZEB2 significantly impaired the suppressive effects of circZFR silencing on bladder cancer cells growth, migration and invasion. Taken together, our results illuminated that circZFR could be a prognostic biomarker in bladder cancer and exerted oncogenic roles through regulating miR-377/ZEB2 axis in bladder cancer, which indicated that circZFR could be a potential therapeutic target for bladder cancer patients treatment.

MiR-27a-5p regulates apoptosis of liver ischemia-reperfusion injury in mice by targeting Bach1.

Ischemia-reperfusion (I/R) injury causes cellular dysfunction and a series of immune or apoptotic reactions. Bach1 is a mammalian transcription factor that represses Hmox1, which encodes heme oxygenase-1 (HO-1) that can degrade heme into free iron, carbon monoxide, and biliverdin, to play an important role in antioxidant, anti-inflammatory, and antiapoptotic activities. MicroRNAs (miRNAs) can be found in a variety of eukaryotic cells and viruses, a class of noncoding small RNAs that are encoded by endogenous genes. The aims of this study were to determine whether miR-27a-5p targets Bach1 and regulates cellular death; the dual-luciferase reporter assay was used to detect this and the results showed that miR-27a-5p significantly decreased the luciferase activity of the Bach1 3'-untranslated region. MiR-27a-5p was increased in mice during hepatic I/R and Bach1 was decreased. By transfecting the AML12 cells with the mimic, inhibitor miR-27a-5p in hypoxia/reoxygenation (H/R) models showed that overexpression of miR-27a-5p decreased Bach1 messenger RNA, upregulated HO-1 expression, and promoted antiapoptotic Bcl-2 and downregulated proapoptotic caspase-3 gene expression. In contrast, the miR-27a-5p inhibitor yielded the opposite results. Meanwhile, transfection with Bach1 small interference RNA obviously upregulated the protein levels of HO-1 and resulted in an increase in Bcl-2 and a decrease in caspase-3 protein levels. Thus, we can conclude that miR-27a-5p is relevant to liver I/R injury and overexpression of miR-27a-5p may alleviate apoptosis in H/R injury by targeting Bach1 in vitro.

The long noncoding RNA ZFAS1 facilitates bladder cancer tumorigenesis by sponging miR-329.

The incidence and mortality rate of bladder cancer have dramatically expanded, so it's urgent to discover new biomarker and therapeutic target for bladder cancer. Recently, lncRNA has been identified as oncogene or tumor suppressor to regulate the tumorigenesis. LncRNA ZFAS1 has been confirmed as oncogene in various tumors. However, the expression, function, and underlying mechanism of ZFAS1 in bladder carcinogenesis have yet to be totally clarified. In the current study, our data demonstrated that ZFAS1 expression was significantly upregulated in bladder cancer tissues and cell lines. Furthermore, Kaplan-Meier analysis revealed that high ZFAS1 expression was significantly associated with unfavorable progression free survival (PFS) (P = 0.0034 < 0.01) and overall survival (OS) (P = 0.0041 < 0.01) of bladder cancer patients. Moreover, silencing of ZFAS1 expression could markedly suppress bladder cancer cells proliferation and colony formation, arrest cell cycle, promote cell apoptosis and inhibit cell migration in vitro. In addition, bioinformatics analysis, luciferase reporter assay, and pull down assay revealed that ZFAS1 straightly interacted with miR-329. Lastly, rescue experiments confirmed that miR-329 inhibitor reversed the tumor suppressing roles of ZFAS1 knockdown on bladder cancer cells. Collectively, our results illuminated that ZFAS1 could serve as an oncogene in the tumorigenesis of bladder cancer, and discovered the functional regulatory network of ZFAS1 sponging miR-329.

The luminescence properties of Sr2-1.5x-1.5y P2 O7 :xDy3+ ,yCe3+ phosphor for near-UV-based white LEDs synthesized by a chemical co-precipitation method.

A series of Sr2 P2 O7 :Dy3+ , Sr2 P2 O7 :Ce3+ and Sr2 P2 O7 :Dy3+ ,Ce3+ phosphors was synthesized via the one-step calcination process for the precursors prepared by co-precipitation methods. The phases, morphology, quantum efficiency and photoluminescence properties of the obtained phosphors were characterized systematically. These results show that the near-spherical particles prepared through calcining the precursors by means of ammonium dibasic phosphate co-precipitation (method 3) have the smallest particle size and strongest emission intensity among the three methods in the paper. With Dy3+ concentration increasing in Sr2 P2 O7 :Dy3+ phosphors, the luminescence intensity first increases, reaches maximum, and then decreases. A similar trend was followed by Sr2 P2 O7 :Ce3+ with Ce3+ concentration increasing. A successful attempt was made to initiate the energy transfer mechanism from Ce3+ to Dy3+ in the host lattice and an overlap between the emission band of Ce3+ and the excitation band of Dy3+ indicated that the Ce3+  â†’ Dy3+ energy transfer may indeed exist. It is clear that the photoluminescence intensity of Dy3+ as well as the quantum efficiency of the phosphor can be enhanced markedly by co-doping Ce3+ . Sr2 P2 O7 :Dy3+ ,Ce3+ has its (CIE) chromaticity coordinates in the bluish-white-light region, near the standard illuminant D65 . The CIE 1913 chromaticity coordinates of Sr2 P2 O7 :Dy3+ phosphors fall in the white-light region, and are adjacent to the ideal white-light coordinates. In addition, the colour temperature and colour tone of Sr2 P2 O7 :Dy3+ could be adjusted by changing the relative concentration of Dy3+ . In short, Sr2 P2 O7 :Dy3+ can be a promising single-phased white-light emitting phosphor for near-UV (NUV) w-LEDs.

NADPH oxidase inhibitor regulates microRNAs with improved outcome after mechanical reperfusion.

BACKGROUND: Inhibition of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) pathway improves the neurological outcome in the transient middle cerebral artery occlusion (tMCAO) animal model. In this study we analyzed the microRNAs profile targeting NOX2 and NOX4 genes and its response to NOX2/4 inhibitor VAS2870 to understand the mechanisms of this protective effect. METHODS: The intraluminal filament tMCAO model was established in hyperglycemic rats (n=106) with 5 hours ischemia followed by 19 hours reperfusion. NOX inhibitor VAS2870 was delivered intravenously before reperfusion. Infarct volume, hemorrhagic transformation, and mortality were determined at 24 hours after cerebral ischemia. MicroRNAs profile targeting NOX2 and NOX4 genes were predicted by microRNA databases and further evaluated by microRNA microarray and quantitative RT-PCR. RESULTS: Ten microRNAs potentially targeting NOX2 and NOX4 genes (including microRNA-29a, microRNA-29c, microRNA-126a, microRNA-132, microRNA-136, microRNA-138, microRNA-139, microRNA-153, microRNA-337, and microRNA-376a) were significantly downregulated in the ischemic hemisphere in the tMCAO group compared with the sham-operated group, as shown by microRNA microarray and quantitative RT-PCR (all p<0.05). Intravenous treatment with NOX inhibitor VAS2870 before reperfusion increased the expression of microRNA-29a, microRNA-29c, microRNA-126a, and microRNA-132 compared with the tMCAO group (all p<0.05). CONCLUSIONS: Several microRNAs potentially targeting NOX2 and NOX4 genes displayed altered levels in hyperglycemic rats with the tMCAO model, suggesting their regulatory roles and targeting potentials for acute ischemic stroke treatment. Targeting specific microRNAs may represent a novel intervention opportunity to improve outcome and reduce hemorrhagic transformation after mechanical reperfusion for acute ischemic stroke.

NADPH oxidase inhibitor improves outcome of mechanical reperfusion by suppressing hemorrhagic transformation.

BACKGROUND: Severe hemorrhagic transformation (HT) after mechanical thrombectomy predicts a poor clinical outcome in acute ischemic stroke. To better understand the mechanism of HT, we investigated the role of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) in HT after reperfusion during acute stroke and whether NOX2/4 inhibitor VAS2870 reduces reperfusion-induced HT after mechanical recanalization. METHODS: A model of reperfusion-induced HT was established in rats (n=182) with hyperglycemic challenge and 5 h middle cerebral artery occlusion followed by 19 h reperfusion. NOX inhibitor VAS2870 was delivered intravenously 30 min before reperfusion. Infarct volume, brain water content, HT, neurological score, mortality rate, blood-brain barrier (BBB) damage, neuronal apoptosis, and reactive oxygen species were determined at 24 h after cerebral ischemia. The expressions of NOX1, NOX2, NOX4, and BBB-associated proteins were measured. RESULTS: NOX2 and NOX4 upregulation and severe HT were observed in hyperglycemic rats after cerebral ischemia/reperfusion. VAS2870 suppressed oxidative stress, neuronal apoptosis, and NOX2/4 upregulation in the ischemic hemisphere. VAS2870 reduced infarct volume (17.2±5.3% vs 37.4±9.2%, p<0.01) and the frequency of reperfusion-induced parenchymal hematoma (29.7% vs 59.5%, p<0.05) at 24 h after ischemia compared with the ischemia/reperfusion group. VAS2870 attenuated brain edema and reduced reperfusion-induced BBB breakdown, resulting in improved neurological outcome (neurological deficit score 1.43±0.50 vs 2.43±0.93, p<0.001) and reduced mortality (11.9% vs 64.1%, p<0.001). CONCLUSIONS: NOX2 and NOX4 may mediate HT in rats with large vessel stroke after mechanical reperfusion. Infusion of NOX inhibitor VAS2870 before mechanical thrombectomy represents a novel adjunctive therapeutic strategy to prevent reperfusion-induced HT and improve outcome of acute stroke treatment.

The luminescent properties and crystal structure of Sr(1.5-x)-(1.5y) Mg0.5 SiO4 :xEu2+ ,yCe3+ blue phosphor synthesized by co-precipitation method.

In order to improve the luminescent performance of silicate blue phosphors, Sr(1.5-x)-(1.5y) Mg0.5 SiO4 :xEu2+ ,yCe3+ phosphors were synthesized using one-step calcination of a precursor prepared by chemical co-precipitation. The crystal structure and luminescent properties of the phosphors were analyzed using X-ray diffraction and fluorescence spectrophotometry, respectively. Because the activated ions (Eu2+ ) can occupy two different types of sites (Sr1 and Sr2 ), the emission spectrum of Eu2+ excited at 350 nm contains two single bands (EM1 and EM2 ) in the wavelength range 400-550 nm, centered at 463 nm, and the emission intensity first increases and then decreases with increasing concentrations of Eu2+ ions. Co-doping of Ce3+ ions can greatly enhance the emission intensity of Eu2+ by transferring its excitation energy to Eu2+ . Because of concentration quenching, a higher substitution concentration of Ce3+ can lead to a decrease in the intensity. Meanwhile, the quantum efficiency of the phosphor is improved after doping with Ce3+ , and a blue shift phenomenon is observed in the CIE chromaticity diagram. The results indicate that Sr(1.5-x)-(1.5y) Mg0.5 SiO4 :xEu2+ ,yCe3+ can be used as a potential new blue phosphor for white light-emitting diodes.

The B3 Subunit of the Cone Cyclic Nucleotide-gated Channel Regulates the Light Responses of Cones and Contributes to the Channel Structural Flexibility.

Cone photoreceptor cyclic nucleotide-gated (CNG) channels play a pivotal role in cone phototransduction, which is a process essential for daylight vision, color vision, and visual acuity. Mutations in the cone channel subunits CNGA3 and CNGB3 are associated with human cone diseases, including achromatopsia, cone dystrophies, and early onset macular degeneration. Mutations in CNGB3 alone account for 50% of reported cases of achromatopsia. This work investigated the role of CNGB3 in cone light response and cone channel structural stability. As cones comprise only 2-3% of the total photoreceptor population in the wild-type mouse retina, we used Cngb3(-/-)/Nrl(-/-) mice with CNGB3 deficiency on a cone-dominant background in our study. We found that, in the absence of CNGB3, CNGA3 was able to travel to the outer segments, co-localize with cone opsin, and form tetrameric complexes. Electroretinogram analyses revealed reduced cone light response amplitude/sensitivity and slower response recovery in Cngb3(-/-)/Nrl(-/-) mice compared with Nrl(-/-) mice. Absence of CNGB3 expression altered the adaptation capacity of cones and severely compromised function in bright light. Biochemical analysis demonstrated that CNGA3 channels lacking CNGB3 were more resilient to proteolysis than CNGA3/CNGB3 channels, suggesting a hindered structural flexibility. Thus, CNGB3 regulates cone light response kinetics and the channel structural flexibility. This work advances our understanding of the biochemical and functional role of CNGB3 in cone photoreceptors.

Chromophore supply rate-limits mammalian photoreceptor dark adaptation.

Efficient regeneration of visual pigment following its destruction by light is critical for the function of mammalian photoreceptors. Here, we show that misexpression of a subset of cone genes in the rd7 mouse hybrid rods enables them to access the normally cone-specific retina visual cycle. The rapid supply of chromophore by the retina visual cycle dramatically accelerated the mouse rod dark adaptation. At the same time, the competition between rods and cones for retina-derived chromophore slowed cone dark adaptation, indicating that the cone specificity of the retina visual cycle is key for rapid cone dark adaptation. Our findings demonstrate that mammalian photoreceptor dark adaptation is dominated by the supply of chromophore. Misexpression of cone genes in rods may represent a novel approach to treating visual disorders associated with mutations of visual cycle proteins or with reduced retinal pigment epithelium function due to aging.

Matrix metalloproteinase-9 expression in carotid atherosclerotic plaque and contrast-enhanced MRI in a swine model.

BACKGROUND: A swine model of carotid atherosclerosis may greatly facilitate the identification of imaging characteristics of vulnerable plaques and the preclinical evaluation of endovascular intervention. In this study we assess the association of matrix metalloproteinase (MMP)-9 expression and neovascularity in carotid atherosclerotic plaques with MRI patterns in a swine model. METHODS: Carotid atherosclerosis models were created in miniswine using a combination of partial ligation and a high cholesterol diet. The animals were imaged in a 1.5 T MR scanner at 3 months and carotid arteries were obtained for histopathological and immunohistochemical examination. Contrast-enhanced T1-weighted imaging (T1WI) was used to match the histology findings. The contrast-to-noise ratio (CNR) of the plaques on T1WI and contrast-enhanced T1WI were measured and the association of MMP-9 expression and neovascularity in the carotid plaque with CNR on MRI was analyzed. RESULT: Forty carotid artery segments were matched between MRI and histology. All segments were advanced carotid atherosclerotic plaques. The matched contrast-enhanced T1WI and histology slices showed good correlation for ratio of plaque size to lumen diameter (r=0.94, p<0.001). Plaque CNR on contrast-enhanced T1WI was higher in plaques with strong MMP-9 expression than in those with weak MMP-9 expression (p=0.05). Plaque CNR on contrast-enhanced T1WI was also higher in plaques with marked neovascularization than in those without (p=0.02). CONCLUSIONS: Increased plaque CNR on contrast-enhanced T1WI is associated with MMP-9 expression and neovascularization in carotid atherosclerotic plaques and may be used to identify vulnerable plaques.

Overexpression of matrix metalloproteinase-9 is correlated with carotid intraplaque hemorrhage in a swine model.

OBJECTIVE: Carotid intraplaque hemorrhage may result in rapid worsening of stenosis and thrombus formation leading to stroke in patients with carotid atherosclerosis. The purpose of this study was to assess the association of the lesional expression of matrix metalloproteinase (MMP)-9 with carotid plaque and intraplaque hemorrhage in a swine model. METHODS: Carotid atherosclerosis was induced in miniswine using a combination of partial ligation and a high cholesterol diet. The carotid artery and rete mirabile were obtained for histopathological and immunohistochemical studies at 3 months. Atherosclerotic changes were classified by Stary stage according to the American Heart Association and the features of vulnerable carotid plaque were assessed. The association of MMP-9 expression in the carotid plaque with intraplaque hemorrhage was analyzed. RESULTS: One hundred and ninety-one carotid segments from 10 carotid artery models were assessed. Among 139 segments with atherosclerotic changes, 102 had advanced plaque (Stary stage IV-VI). Atheroemboli were found in all 10 rete mirabili, confirming the presence of vulnerable ipsilateral carotid plaques. There was a trend to increased MMP-9 expression in the group with advanced plaque. Areas positive for MMP-9 were significantly greater in plaques with intraplaque hemorrhage than in those without intraplaque hemorrhage (11.84±1.22% vs 6.63±0.59%, p<0.001). CONCLUSIONS: Increased expression of MMP-9 is associated with intraplaque hemorrhage in a swine model of vulnerable carotid atherosclerosis.

Interphotoreceptor retinoid-binding protein as the physiologically relevant carrier of 11-cis-retinol in the cone visual cycle.

Cones function in constant light and are responsible for mediating daytime human vision. Like rods, cones use the photosensitive molecule 11-cis-retinal to detect light, and in constant illumination, a continuous supply of 11-cis-retinal is needed. A retina visual cycle is thought to provide a privileged supply of 11-cis-retinal to cones by using 11-cis-retinol generated in Müller cells. In the cycle, 11-cis-retinol is transported from Müller cells to cone inner segments, where it is oxidized to 11-cis-retinal. This oxidation step is only performed in cones, thus rendering the cycle cone-specific. Interphotoreceptor retinoid-binding protein (IRBP) is a retinoid-binding protein in the subretinal space that binds 11-cis-retinol endogenously. Cones in Irbp(-/-) mice are retinoid-deficient under photopic conditions, and it is possible that 11-cis-retinol supplies are disrupted in the absence of IRBP. We tested the hypothesis that IRBP facilitates the delivery of 11-cis-retinol to cones by preserving the isomeric state of 11-cis-retinol in light. With electrophysiology, we show that the cone-like photoreceptors of Nrl(-/-) mice use the cone visual cycle similarly to wild-type cones. Then, using oxidation assays in isolated Nrl(-/-)Rpe65(-/-) retinas, we show that IRBP delivers 11-cis-retinol for oxidation in cones and improves the efficiency of the oxidation reaction. Finally, we show that IRBP protects the isomeric state of 11-cis-retinol in the presence of light. Together, these findings suggest that IRBP plays an important role in the delivery of 11-cis-retinol to cones and can facilitate cone function in the presence of light.

The cone-specific visual cycle.

Cone photoreceptors mediate our daytime vision and function under bright and rapidly-changing light conditions. As their visual pigment is destroyed in the process of photoactivation, the continuous function of cones imposes the need for rapid recycling of their chromophore and regeneration of their pigment. The canonical retinoid visual cycle through the retinal pigment epithelium cells recycles chromophore and supplies it to both rods and cones. However, shortcomings of this pathway, including its slow rate and competition with rods for chromophore, have led to the suggestion that cones might use a separate mechanism for recycling of chromophore. In the past four decades biochemical studies have identified enzymatic activities consistent with recycling chromophore in the retinas of cone-dominant animals, such as chicken and ground squirrel. These studies have led to the hypothesis of a cone-specific retina visual cycle. The physiological relevance of these studies was controversial for a long time and evidence for the function of this visual cycle emerged only in very recent studies and will be the focus of this review. The retina visual cycle supplies chromophore and promotes pigment regeneration only in cones but not in rods. This pathway is independent of the pigment epithelium and instead involves the Müller cells in the retina, where chromophore is recycled and supplied selectively to cones. The rapid supply of chromophore through the retina visual cycle is critical for extending the dynamic range of cones to bright light and for their rapid dark adaptation following exposure to light. The importance of the retina visual cycle is emphasized also by its preservation through evolution as its function has now been demonstrated in species ranging from salamander to zebrafish, mouse, primate, and human.

Fields of applications, diagnostic yields and findings of OMOM capsule endoscopy in 2400 Chinese patients.

AIM: To retrospectively analyze the fields of application, diagnostic yields and findings of OMOM capsule endoscopy in Chinese patients. METHODS: A database including 2400 Chinese patients who received OMOM capsule endoscopy in 27 endoscopy centers in China was retrieved from the Jianshan Science and Technology Ltd. OMOM capsule endoscopy database. The patient's age, gender, fields of application, the potentially relevant findings, pyloric transit time (PTT), small bowel transit time (SBTT), and complete small-bowel examination rate (CSER) were recorded and analyzed. RESULTS: Two thousand four hundred patients aged 9-91 years (mean, 49 years), of whom 1510 were males (62.9%), underwent 2400 OMOM capsule endoscopy procedures. One thousand two hundred and thirty two (51.3%) were referred with obscure gastrointestinal bleeding (OGIB), 642 (26.8%) with abdominal pain, and 223 (9.3%) with chronic diarrhea. The overall diagnostic yield was 47.7% (1144/2400). The diagnostic yield of OMOM capsule endoscopy in OGIB subgroup was much higher than in the non-OGIB subgroup (62.4% vs 32.1%, P < 0.001). The most common findings of the small bowel in Chinese patients with OGIB were arteriovenous malformation (28.1%) and tumors (18.9%). There was no significant difference in the diagnostic yield between the male and female patients with OGIB. However, the diagnostic yield in patients aged more than 60 was higher than in patients aged less than 60 (69.8% vs 58.9%, P < 0.001). The median PTT was 41 min (range: 1-544 min) and the mean SBTT was 247.2 +/- 88.9 min. The overall CSER was 86.8%. CONCLUSION: The OMOM capsule endoscopy is a valuable tool for small bowel evaluation with good overall diagnostic yield and CSER.

Single-cell suction recordings from mouse cone photoreceptors.

Rod and cone photoreceptors in the retina are responsible for light detection. In darkness, cyclic nucleotide-gated (CNG) channels in the outer segment are open and allow cations to flow steadily inwards across the membrane, depolarizing the cell. Light exposure triggers the closure of the CNG channels, blocks the inward cation current flow, and thus results in cell hyperpolarization. Based on the polarity of photoreceptors, a suction recording method was developed in 1970s that, unlike the classic patch-clamp technique, does not require penetrating the plasma membrane. Drawing the outer segment into a tightly-fitting glass pipette filled with extracellular solution allows recording the current changes in individual cells upon test-flash exposure. However, this well-established "outer-segment-in (OS-in)" suction recording is not suitable for mouse cone recordings, because of the low percentage of cones in the mouse retina (3%) and the difficulties in identifying the cone outer segments. Recently, an inner-segment-in (IS-in) recording configuration was developed to draw the inner segment/nuclear region of the photoreceptor into the recording pipette. In this video, we will show how to record from individual mouse cone photoresponses using single-cell suction electrode.

An alternative pathway mediates the mouse and human cone visual cycle.

One of the fundamental mysteries of the human visual system is the continuous function of cone photoreceptors in bright daylight. As visual pigment is destroyed, or bleached, by light, cones require its rapid regeneration, which in turn involves rapid recycling of the pigment's chromophore. The canonical visual cycle for rod and cone pigments involves recycling of their chromophore from all-trans retinol to 11-cis retinal in the pigment epithelium, adjacent to photoreceptors. However, shortcomings of this pathway indicate the function of a second, cone-specific, mechanism for chromophore recycling. Indeed, biochemical and physiological studies on lower species have described a cone-specific visual cycle in addition to the long-known pigment epithelium pathway. Two important questions remain, however: what is the role of this pathway in the function of mammalian cones, and is it present in higher mammals, including humans? Here, we show that mouse, primate, and human neural retinas promote pigment regeneration and dark adaptation selectively in cones, but not in rods. This pathway supports rapid dark adaptation of mammalian cones and extends their dynamic range in background light independently of the pigment epithelium. This pigment-regeneration mechanism is essential for our daytime vision and appears to be evolutionarily conserved.

Intra-retinal visual cycle required for rapid and complete cone dark adaptation.

Daytime vision is mediated by retinal cones, which, unlike rods, remain functional even in bright light and dark-adapt rapidly. These cone properties are enabled by rapid regeneration of their pigment. This in turn requires rapid chromophore recycling that may not be achieved by the canonical retinal pigment epithelium visual cycle. Recent biochemical studies have suggested the presence of a second, cone-specific visual cycle, although its physiological function remains to be established. We found that the Müller cells in the salamander neural retina promote cone-specific pigment regeneration and dark adaptation that are independent of the pigment epithelium. Without this pathway, dark adaptation of cones was slow and incomplete. Notably, the rates of cone pigment regeneration by the retina and pigment epithelium visual cycles were essentially identical, suggesting a possible common rate-limiting step. Finally, we also observed cone dark adaptation in the isolated mouse retina.

[Clinical analysis of donor hepatectomy in living donor liver transplantation: report of 74 cases].

OBJECTIVE: To evaluate the living donor selection, donor hepatectomy technique, and surgical complication in living donor liver transplantation. METHODS: From June 2007 to July 2008, 74 consecutive cases living donor hepatectomy were performed by the same surgical team. Seventy-four donors (64 males and 10 females) with a mean age of 29.2 years old passed the donor liver assessment and evaluation program successfully. The hepatectomy procedure types contained right liver resection (n = 72), of which 27 cases harvested the middle hepatic vein and 45 cases not, left liver resection contain middle hepatic vein (n = 1) and left lateral resection (n = 1). RESULTS: Of all the donors, operation time was (6.5 +/- 6.2) hours, the mean blood loss was 300 ml (100 - 500 ml) and didn't accept foreign blood transfusion. The maximum alanine aminotransferase (ALT) level was (229.5 +/- 108.6) U/L, the ALT returned to normal time was (12.7 +/- 4.8) d, the maximum total bilirubin (TB) level was (78.7 +/- 44.3) micromol/L, the TB returned to normal time was (8.8 +/- 2.7) d, and the mean hospital stay time was 14 days (7 - 28 d). The complications included bile leak (n = 1), cut surface hemorrhage (n = 1) and anaphylactoid purpura (n = 1). All the donors returned to normal work and life finally. CONCLUSIONS: Precisely evaluating donor blood vascular and biliary anatomy before operation, keeping the blood vascular and bile duct integrity during operation and monitoring complication to solve it immediately after operation is crucial to ensure donor safety and recovering successfully.