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Summary: There is an urgent need for an oral, efficient and safe regimen for high‐risk APL under the pandemic of COVID‐19. We retrospectively analysed 60 high‐risk APL patients. For induction therapy (IT), in addition to all‐trans retinoic acid (ATRA) and oral arsenic (RIF), 22 patients received oral etoposide (VP16) as cytotoxic chemotherapy (CC), and 38 patients received intravenous CC as historical control group. The median dose of oral VP16 was 1000 mg [interquartile rage (IQR), 650–1250]. One patient died during IT in the control group, 59 evaluable patients (100%) achieved complete haematological remission (CHR) after IT and complete molecular remission (CMR) after consolidation therapy. The median time to CHR and CMR was 36 days (33.8–44) versus 35 days (32–42; p = 0.75) and 3 months (0.8–3.5) versus 3.3 months (2.4–3.7; p = 0.58) in the oral VP16 group and in the control group. Two (9.1%) and 3 (7.9%) patients experienced molecular relapse in different group respectively. The 2‐year estimated overall survival and event‐free survival were 100% versus 94.7% (p = 0.37) and 90.9% versus 89.5% (p = 0.97) respectively. A completely oral, efficient and safe induction regimen including oral VP16 as cytoreductive chemotherapy combined with ATRA and RIF is more convenient to administer for patients with high‐risk APL. [ABSTRACT FROM AUTHOR]

Objective: To assess the extent of recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN) damage in patients with idiopathic vocal cord paralysis (IVCP) exhibiting different paralytic sides. Methods: A total of 84 IVCP cases were evaluated using stroboscopic laryngoscopy, voice analysis, and laryngeal electromyography (LEMG). The results were compared between patients with left‐sided paralysis and right‐sided paralysis based on different disease courses (less than or more than 3 months). Results: Initially, the average age and disease progression of IVCP patients were found to be similar regardless of the side of paralysis (p >.05). Additionally, there were no significant variations in voice indicators, such as MPT, DSI, and VHI, between IVCP patients with left and right vocal cord paralysis (p >.05). Furthermore, no disparities were detected in the latencies and amplitudes of the paralyzed RLN and SLN, as well as the durations and amplitudes of the action potentials in the paralyzed TM and PCM, among IVCP patients with left and right vocal cord paralysis (p >.05). Notably, the amplitudes of the left paralytic CM were significantly lower than those of the right paralytic CM (0.45 vs. 0.53, Z = −2.013, p =.044). In addition, no disparities were observed in APDs and amplitudes between the ipsilateral PCM and TM, either for patients with left or right vocal fold paralysis (p >.05). Finally, all the IVCP patients were subdivided into two subgroups according to different disease course (less than or more than 3 months), and in each subgroup, the comparison of voice indicators and LEMG results in IVCP patients with left or right vocal fold paralysis were similar with the above findings (p >.05). Conclusion: Overall, the degree of RLN and SLN damage appeared to be similar in IVCP patients with left and right vocal cord paralysis, provided that the disease course was comparable. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae is a pathogenic fungus that seriously harms rice production. Phosphatases and carbon metabolism play crucial roles in the growth and development of eukaryotes. However, it remains unclear how serine/threonine phosphatases regulate the catabolism of triglycerides, a major form of stored lipids. In this study, we identified a serine/threonine protein phosphatase regulatory subunit, Smek1, which is required for the growth, conidiation, and virulence of M. oryzae. Deletion of SMEK1 led to defects in the utilization of lipids, arabinose, glycerol, and ethanol. In glucose medium, the expression of genes involved in lipolysis, long‐chain fatty acid degradation, β‐oxidation, and the glyoxylate cycle increased in the Δsmek1 mutant, which is consistent with ΔcreA in which a carbon catabolite repressor CREA was deleted. In lipid medium, the expression of genes involved in long‐chain fatty acid degradation, β‐oxidation, the glyoxylate cycle, and utilization of arabinose, ethanol, or glycerol decreased in the Δsmek1 mutant, which is consistent with Δcrf1 in which a transcription activator CRF1 required for carbon metabolism was deleted. Lipase activity, however, increased in the Δsmek1 mutant in both glucose and lipid media. Moreover, Smek1 directly interacted with CreA and Crf1, and dephosphorylated CreA and Crf1 in vivo. The phosphatase Smek1 is therefore a dual‐function regulator of the lipid and carbohydrate metabolism, and controls fungal development and virulence by coordinating the functions of CreA and Crf1 in carbon catabolite repression (CCR) and derepression (CCDR). [ABSTRACT FROM AUTHOR]

Objective: This study aimed to analyze the characteristics of laryngopharyngeal reflux (LPR) by using narrow band imaging (NBI) endoscopy. Study Design: A prospective study. Setting: A large‐volume practice with tertiary care providers. Methods: A total of 67 patients with suspected LPR who underwent 24‐hour multichannel intraluminal impedance–pH monitoring were included from June 2020 to March 2022. Manifestations of NBI endoscopy included submucosal clustered brownish microvessels (CBMs), spotted brownish microvessels, and no special microvessels; the latter 2 formed the non‐CBM group. The manifestations of all patients and their changes were observed after 8 weeks of proton pump inhibitor and symptomatic treatment for patients with LPR, and symptomatic treatment for patients without LPR. Results: According to the results of 24‐hour multichannel intraluminal impedance–pH monitoring, the incidence of submucosal CBMs was significantly higher in patients with LPR (30 cases) than in those without LPR (37 cases, P <.001), particularly in the posterior cricoid area (P <.001). Besides Reflux Finding Score, the incidence of signs such as subglottic edema and vocal fold edema was significantly higher in the CBM group than the non‐CBM group (P <.05). Finally, 22 patients with LPR (91.7%) and only 2 patients without LPR (28.6%) underwent a transformation from CBMs to spotted brownish microvessels after continuous medication for 8 weeks in the CBM group (χ2 = 15.916, P <.001), while no significant change was observed in patients with or without LPR in the non‐CBM group (P >.05). Conclusion: Submucosal CBMs in the posterior cricoid area under NBI endoscopy may be a characteristic of LPR. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Summary: The development and pathogenicity of the fungus Magnaporthe oryzae, the causal agent of destructive rice blast disease, require it to perceive external environmental signals. Opy2, an overproduction‐induced pheromone‐resistant protein 2, is a crucial protein for sensing external signals in Saccharomyces cerevisiae. However, the biological functions of the homologue of Opy2 in M. oryzae are unclear. In this study, we identified that MoOPY2 is involved in fungal development, pathogenicity, and autophagy in M. oryzae. Deletion of MoOPY2 resulted in pleiotropic defects in hyphal growth, conidiation, germ tube extension, appressorium formation, appressorium turgor generation, and invasive growth, therefore leading to attenuated pathogenicity. Furthermore, MoOpy2 participates in the Osm1 MAPK pathway and the Mps1 MAPK pathway by interacting with the adaptor protein Mst50. The interaction sites of Mst50 and MoOpy2 colocalized with the autophagic marker protein MoAtg8 in the preautophagosomal structure sites (PAS). Notably, the ΔMoopy2 mutant caused cumulative MoAtg8 lipidation and rapid GFP‐MoAtg8 degradation in response to nitrogen starvation, showing that MoOpy2 is involved in the negative regulation of autophagy activity. Taken together, our study revealed that MoOpy2 of M. oryzae plays an essential role in the orchestration of fungal development, appressorium penetration, autophagy and pathogenesis. [ABSTRACT FROM AUTHOR]

Summary: Magnaporthe oryzae is an important plant pathogen that causes rice blast. Hse1 and Vps27 are components of ESCRT‐0 involved in the multivesicular body (MVB) sorting pathway and biogenesis. To date, the biological functions of ESCRT‐0 in M. oryzae have not been determined. In this study, we identified and characterized Hse1 and Vps27 in M. oryzae. Disruption of MoHse1 and MoVps27 caused pleiotropic defects in growth, conidiation, sexual development and pathogenicity, thereby resulting in loss of virulence in rice and barley leaves. Disruption of MoHse1 and MoVps27 triggered increased lipidation of MoAtg8 and degradation of GFP‐MoAtg8, indicating that ESCRT‐0 is involved in the regulation of autophagy. ESCRT‐0 was determined to interact with coat protein complex II (COPII), a regulator functioning in homeostasis of the endoplasmic reticulum (ER homeostasis), and disruption of MoHse1 and MoVps27 also blocked activation of the unfolded protein response (UPR) and autophagy of the endoplasmic reticulum (ER‐phagy). Overall, our results indicate that ESCRT‐0 plays critical roles in regulating fungal development, virulence, autophagy and ER‐phagy in M. oryzae. [ABSTRACT FROM AUTHOR]

Summary: Despite the high cure probability for acute promyelocytic leukaemia (APL), a minority of patients will relapse and the risk factors for relapse are unclear. We retrospectively analysed 212 patients who were diagnosed with non‐high‐risk APL and received all‐trans retinoic acid (ATRA) plus arsenic as front‐line therapy at Peking University Institute of Hematology from February 2014 to December 2018. A total of 176 patients (83%) received oral arsenic (realgar‐indigo naturalis formula) plus ATRA, 36 patients (17%) received arsenic trioxide plus ATRA and 203 patients were evaluable for relapse. After a median (range) follow‐up of 53·6 (24·3–85·4) months, two patients had molecular relapse and eight had haematological relapse. A promyelocytic leukaemia/retinoic acid receptor alpha (PML‐RARA) transcript level of ≥6·5% at the end of induction therapy was associated with relapse (P = 0·031). The 5‐year cumulative incidence of relapse, event‐free survival and overall survival were 5·5%, 92·3% and 96·3% respectively. In conclusion, the present long‐term follow‐up study further confirmed the high cure probability of ATRA plus oral arsenic as front‐line therapy for non‐high‐risk APL and showed that the PML‐RARA transcript level at the end of induction therapy was associated with relapse. [ABSTRACT FROM AUTHOR]

TQ‐B3203 is a new topoisomerase I inhibitor derived from camptothecin. In this paper, a simple and reliable ultra high‐performance liquid chromatography‐tandem mass spectrometric method was developed and validated for determination of TQ‐B3203 in human plasma with TQ‐B3203‐d8 used as the internal standard. Bis(p‐nitrophenyl)phosphate (2 mol/L) was added to ensure the stability of TQ‐B3203 in human plasma. Plasma samples were protein precipitated by methanol and processed samples were chromatographed on an AQUITY BEH C8 column (50 × 2.1 mm, id 1.7 μm) with acetonitrile and water (0.1% formic acid) as the mobile phase. The calibration curves showed good linearity (R≥0.99) over the concentration range of 0.5–500 ng/mL. Within‐ and between‐run precision were ≤5.8% and the accuracy was within the range of −8.3 to 14.0%. This method was further successfully applied to a pharmacokinetic study of TQ‐B3203 in Chinese advanced solid cancer patients after administration of TQ‐B3203 liposome injection. [ABSTRACT FROM AUTHOR]

Summary: Amino acids are vital components in cell metabolism. Leucine is a regulatory factor that generates significant impact on protein synthesis/turnover, modulates diverse cellular signalling pathways and participates in oxidative processes and immune responses. Here, we identified and characterized the functions of a leucine‐associated Zn2Cys6‐type transcription factor, MoLeu3. Disruption of MoLEU3 resulted in significantly reduced pathogenicity in barley and rice. Quantitative RT‐PCR showed that the expression levels of the putative leucine biosynthesis‐related genes, MoLEU1, MoLEU2 and MoLEU4 were downregulated in the ΔMoleu3 mutant. We used high‐throughput gene knockout method to generate the null mutants of MoLEU1, MoLEU2 and MoLEU4 respectively. The ΔMoleu1, ΔMoleu2 and ΔMoleu4 mutants are leucine auxotroph and showed similar phenotypic characterizations, including reduced conidiation, delayed mobilization and degradation of glycogen and lipid droplets, limited appressorium‐mediated penetration, and restricted invasive hyphae growth within host cells. Collectively, MoLEU1, MoLEU2, and MoLEU4 regulated by MoLEU3 play crucial roles in fungal development and infectious processes through modulation of leucine biosynthesis in Magnaporthe oryzae. [ABSTRACT FROM AUTHOR]

Objective: To find new clues to reduce postoperative recurrence after intralesional curettage by studying MRI and pathological features of giant tumor of bone (GCTB) boundaries. Methods: A retrospective study was performed in the departments of orthopaedic surgery and medical imaging at our hospitals from January 2006 to August 2016. A total of 16 GCTB patients confirmed by pathology were asked to participate in the present study. The age range was from 18 to 44 years (9 women and 7 men). All patients underwent MRI examination. All patients underwent en bloc resection and complete postoperative tumor segments were obtained. Five specimens were obtained randomly at the place of the segments where the GCTB boundary showed different types on MRI. Ordinary HE staining was used for all specimens and we measured the depth of local tumor cell infiltration (240 measurements). Results were expressed as means ± standard deviation. Statistical analyses were carried out with one‐way ANOVA and the Student–Newman–Keuls test. P < 0.05 was considered statistically significant. The kappa test was used to analyze the degree of agreement of observers. Results: A total of 16 patients (median age 30.56 years; range, 18–44 years) with GCTB (the number of distal femurs and proximal tibias was 9 and 7, respectively) were tested. The boundaries of all GCTB cases were composed of clear boundary, relatively clear boundary, and blurred boundary in different proportions on MRI. Based on continuous observation of all MRI, all boundaries were incomplete. The kappa value between two radiologists and two pathologists was 0.91 and 0.88, respectively. The average depth of local tumor cell infiltration in the clear boundary, relatively clear boundary, and blurred boundary groups was 0.42 ± 0.11 mm, 2.85 ± 0.21 mm, and 4.83 ± 0.12 mm, respectively. There was statistical difference among the three groups (F = 17.62, P < 0.05). There was also statistical difference between each of the two groups (q‐value was 8.95, 14.28, and 5.21, respectively, P < 0.05). The depth of local tumor cell infiltration with blurred boundaries on MRI was the largest and the depth with clear boundaries was the smallest. Conclusion: The intralesional curettage boundaries need to be expanded on the basis of different types of boundaries provided by MRI. [ABSTRACT FROM AUTHOR]

Summary: The Skp1‐Cul1‐F‐box‐protein (SCF) ubiquitin ligases are important parts of the ubiquitin system controlling many cellular biological processes in eukaryotes. However, the roles of SCF ubiquitin ligases remain unclear in phytopathogenic Magnaporthe oryzae. Here, we cloned 24 F‐box proteins and confirmed that 17 proteins could interact with MoSkp1, showing their potential to participate in SCF complexes. To determine their functions, null mutants of 21 F‐box‐containing genes were created. Among them, the F‐box proteins MoFwd1, MoCdc4 and MoFbx15 were found to be required for growth, development and full virulence. Fluorescent‐microscopy observations demonstrated that both MoFbx15 and MoCdc4 were localized to the nucleus, compared with MoFwd1, which was distributed in the cytosol. MoCdc4 and MoFwd1 bound to MoSkp1 via the F‐box domain, the deletion of which abrogated their function. Race tube and qRT‐PCR assays confirmed that MoFwd1 was involved in circadian rhythm by regulating transcription and protein stability of the core circadian clock regulator MoFRQ. Moreover, MoFWD1 also orchestrates conidial germination by influencing conidial amino acids pools and oxidative stress release. Overall, our results indicate that SCF ubiquitin ligases play indispensable roles in development and pathogenicity in M. oryzae. [ABSTRACT FROM AUTHOR]

Summary: Pyricularia oryzae is the causal pathogen of rice blast disease. Autophagy has been shown to play important roles in P. oryzae development and plant infection. The P. oryzae endosomal system is highly dynamic and has been shown to be associated with conidiogenesis and pathogenicity as well. To date, the crosstalk between autophagy and endocytosis has not been explored in P. oryzae. Here, we identified three P. oryzae VPS9 domain‐containing proteins, PoVps9, PoMuk1 and PoVrl1. We found that PoVps9 and PoMuk1 are localized to vesicles and are each co‐localized with PoVps21, a recognized marker of early endosomes. Deletion of PoVPS9 resulted in severe defects in endocytosis and autophagosome degradation and impaired the localization of PoVps21 to endosomes. Additionally, deletion of the PoMUK1 gene in the ΔPovps9 mutant background exhibited more severe defects in development, autophagy and endocytosis compared with the ΔPovps9 mutant. Pull‐down assay showed that PoVps9 interacts with PoVps21, PoRab11 and PoRab1, which have been verified to participate in endocytosis. Furthermore, yeast two‐hybrid and co‐immunoprecipitation assays confirmed that PoVps9 directly interacts with the GDP form of PoVps21. Thus, PoVps9 is a key protein involved in autophagy and in endocytosis. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is an early hallmark during the clinical course of heart failure and regulated by various signalling pathways. Recently, we observed that mouse embryonic fibroblasts from CD38 knockout mice were significantly resistant to oxidative stress such as H2O2-induced injury and hypoxia/reoxygenation-induced injury. In addition, we also found that CD38 knockout mice protected heart from ischaemia reperfusion injury through activating SIRT1/FOXOs-mediated antioxidative stress pathway. However, the role of CD38 in cardiac hypertrophy is not explored. Here, we investigated the roles and mechanisms of CD38 in angiotensin II (Ang-II)-induced cardiac hypertrophy. Following 14 days of Ang-II infusion with osmotic mini-pumps, a comparable hypertension was generated in both of CD38 knockout and wild-type mice. However, the cardiac hypertrophy and fibrosis were much more severe in wild-type mice compared with CD38 knockout mice. Consistently, RNAi-induced knockdown of CD38 decreased the gene expressions of atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) and reactive oxygen species generation in Ang-II-stimulated H9c2 cells. In addition, the expression of SIRT3 was elevated in CD38 knockdown H9c2 cells, in which SIRT3 may further activate the FOXO3 antioxidant pathway. The intracellular Ca2+ release induced by Ang-II markedly decreased in CD38 knockdown H9c2 cells, which might be associated with the decrease of nuclear translocation of NFATc4 and inhibition of ERK/AKT phosphorylation. We concluded that CD38 plays an essential role in cardiac hypertrophy probably via inhibition of SIRT3 expression and activation of Ca2+-NFAT signalling pathway. Thus, CD38 may be a novel target for treating cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

Apremilast (AP) {systematic name: ( S)-2-[1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl]-4-acetamidoisoindoline-1,3-dione} is an inhibitor of phosphodieasterase-4 (PDE4) and is indicated for the treatment of adult patients with active psoriatic arthritis. The ability of AP to form solvates has been investigated and three solvatomorphs of AP, namely, the AP ethyl acetate hemisolvate, C22H24N2O7S·0.5C4H8O2, the AP toluene hemisolvate, C22H24N2O7S·0.5C7H8, and the AP dichloromethane monosolvate, C22H24N2O7S·CH2Cl2, were obtained. The three AP solvatomorphs were characterized by X-ray powder diffraction, thermogravimetric analysis and differential scanning calorimetry. Single-crystal X-ray diffraction was used to analyze the structures, crystal symmetry, packing modes, stoichiometry and hydrogen-bonding interactions of the solvatomorphs. In addition, dissolution analyses were performed to study the dissolution rates of different AP solvatomorph tablets in vitro and to make comparisons with commercial apremilast tablets (produced by Celgene); all three solvatomorphs showed similar dissolution rates and similar values of the similarity factor f2 in a comparison of their dissolution profiles. [ABSTRACT FROM AUTHOR]

The ubiquitin system modulates protein functions through targeting substrates for ubiquitination. Here, E2 conjugating enzyme MoRad6-related ubiquitination pathways are identified and analyzed in Magnaporthe oryzae, the causal agent of rice blast disease. Disruption of MoRad6 leads to severe defects in growth, sporulation, conidial germination, appressorium formation, and plant infection. To depict the functions of MoRad6, three putative ubiquitin ligases, MoRad18, MoBre1 and MoUbr1, are also characterized. Deletion of MoRad18 causes minor phenotypic changes, while MoBre1 is required for growth, conidiation and pathogenicity in M. oryzae. Defects in ΔMobre1 likely resulted from the reduction in di- and tri-methylation level of Histone 3 lysine 4 (H3K4). Notably, MoUbr1 is crucial for conidial adhesion and germination, possibly by degrading components of cAMP/PKA and mitogen-activated protein kinase (MAPK) Pmk1 signaling pathways via the N-end rule pathway. Germination failure of ΔMoubr1 conidia could be rescued by elevation of cAMP level or enhanced Pmk1 phosphorylation resulting from further deletion of MoIra1, the M. oryzae homolog of yeast Ira1/2. These reveal vital effects of cAMP/PKA and MAPK Pmk1 signaling on conidial germination in M. oryzae. Altogether, our results suggest that MoRad6-mediated ubiquitination pathways are essential for the infection-related development and pathogenicity of M. oryzae. [ABSTRACT FROM AUTHOR]

Rab GTPases are required for vesicle-vacuolar fusion during vacuolar biogenesis in fungi. To date, little is known about the biological functions of the Rab small GTPase components in Magnaporthe oryzae. In this study, we investigated MoYpt7 of M. oryzae, a homologue of the small Ras-like GTPase Ypt7 in Saccharomyces cerevisiae. Cellular localization assays showed that MoYpt7 was predominantly localized to vacuolar membranes. Using a targeted gene disruption strategy, a MoYPT7 mutant was generated that exhibited defects in mycelial growth and production of conidia. The conidia of the MoYPT7 mutant were malformed and defective in the formation of appressoria. Consequently, the MoYPT7 mutant failed to cause disease in rice and barley. Furthermore, the MoYPT7 mutant showed impairment in autophagy, breached cell wall integrity, and higher sensitivity to both calcium and heavy metal stress. Transformants constitutively expressing an active MoYPT7 allele (MoYPT7-CA, Gln67Leu) exhibited distinct phenotypes from the MoYPT7 mutant. Expression of MoYPT7-CA in MoYpt7 reduced pathogenicity and produced more appressoriaforming single-septum conidia. These results indicate that MoYPT7 is required for fungal morphogenesis, vacuole fusion, autophagy, stress resistance and pathogenicity in M. oryzae. [ABSTRACT FROM AUTHOR]

BACKGROUND The root bark of Aralia is a rich source of bioactive components that may improve glycemic control and lipid status. In this study, 148 patients with type 2 diabetes mellitus ( T2DM) were assigned randomly to receive either glipizide alone or glipizide plus Aralia root bark extract ( ARBE) for 8 weeks to test the effects of ARBE plus glipizide therapy on glycemic control and lipid profiles in these patients. RESULTS Levels of HbA1c, fasting plasma glucose ( FPG) and 2 h postprandial plasma glucose (2-h PPG) in both groups significantly decreased from baseline. Glycated hemoglobin ( HbA1c) decreased marginally significantly in participants taking glipizide plus ARBE compared with the glipizide group ( P = 0.06). Participants in the combination group had significant decreases in total cholesterol ( TC) and low-density lipoprotein cholesterol ( LDL-C), and the between-group difference achieved statistical significance for LDL-C ( P = 0.04). Reduction in HbA1c in the combination group was significantly associated with changes in TC ( r = 0.32; P = 0.006) and LDL-C ( r = 0.34; P = 0.005), and the change in FPG was inversely correlated with LDL-C reduction ( r = 0.34; P = 0.004). CONCLUSIONS In patients with T2DM, combination therapy with glipizide and ARBE resulted in moderately lowering HbA1c and LDL-C levels compared with glipizide alone. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The magnocellular neurosecretory cells of the hypothalamus (MNCs) regulate their electrical behaviour as a function of external osmolality through changes in the activity of osmosensitive ion channels. We now present evidence that the MNCs express an osmosensitive voltage-gated K+ current (the OKC). Whole-cell patch-clamp experiments on acutely isolated MNCs were used to show that increases in the external osmolality from 295 to 325 mosmol/kg cause an increase in a slow, tetraethylammonium-insensitive outward current. The equilibrium potential for this current is close to the predicted EK in two different concentrations of external K+. The OKC is sensitive to block by Ba2+ (0.3 mm), and by the M-type K+ current blockers linopirdine (150 μm) and XE991 (5 μm), and to enhancement by retigabine (10 μm), which increases opening of M-type K+ channels. The OKC is suppressed by muscarine (30 μm) and is decreased by the L-type Ca2+ channel blocker nifedipine (10 μm), but not by apamin (100 nm), which blocks SK-type Ca2+-dependent K+ currents. Reverse transcriptase-polymerase chain reaction and immunocytochemical data suggest that MNCs express several members of the KV7 (KCNQ) family of K+ channels, including KV7.2, 7.3, 7.4 and 7.5. Extracellular recordings of individual MNCs in a hypothalamic explant preparation demonstrated that an XE991- and retigabine-sensitive current contribute to the regulation of MNC firing. Our data suggest that the MNCs express an osmosensitive K+ current that could contribute to the regulation of MNC firing by external osmolality and that could be mediated by KV7/M-type K+ channels. [ABSTRACT FROM AUTHOR]

Recreational and occupational exposure to seawater (SW), have increased but the effect of SW on skin has not been elucidated. The purpose of present study was to assess the effects of SW immersion on the dorsal skin in hairless mice. Adult hairless mice were individually immersed in SW for 3 h, 6 h and 12 h; then, full-thickness dorsal skin of 2 cm diameter was excised for pathological examination (light microscope), apoptosis detection (terminal deoxynucleotidyl transferase-mediated 2′-deoxyuridine 5′-triphosphate nick end labeling [TUNEL]) and proliferation index evaluation (immunohistochemistry). Normal and normal saline (NS)-immersed skin were used as controls. Histological examination revealed that there were randomly distributed cell deaths, presenting cell shrinkage, condensation of nuclear chromatin and eosinophilic cytoplasm in the epidermis, and neutrophil infiltration in the dermis, after SW immersion. Moreover, TUNEL showed low levels of apoptosis in normal (9.07 ± 0.70%) and NS-immersed skin (9.99 ± 1.22%). There was an apparent increase in the 6-h and 12-h SW immersed groups (29.90 ± 6.85%, P < 0.01; 45.46 ± 6.12%, P < 0.01, respectively). Ki-67 antigen was located in the basal layer of the epidermis and hair follicles, the rates of Ki-67-positive cells were 7.90 ± 1.45% and 7.76 ± 1.52% in normal and NS-immersed skin, respectively, and in the 12-h SW immersed group, the rate of Ki-67-positive cells reached 23.85 ± 4.21% (threefold, P < 0.01). In each group, the rate of apoptosis was higher than that of proliferation. We conclude that SW immersion can cause time-dependent apoptosis and proliferation in the epidermis, and the overall effect of SW immersion is injury to the epidermis. [ABSTRACT FROM AUTHOR]

The magnocellular neurosecretory cells of the hypothalamus (MNCs) regulate their electrical behaviour as a function of external osmolality through changes in the activity of osmosensitive ion channels. We now present evidence that the MNCs express an osmosensitive voltage-gated K(+) current (the OKC). Whole-cell patch-clamp experiments on acutely isolated MNCs were used to show that increases in the external osmolality from 295 to 325 mosmol/kg cause an increase in a slow, tetraethylammonium-insensitive outward current. The equilibrium potential for this current is close to the predicted E(K) in two different concentrations of external K(+). The OKC is sensitive to block by Ba(2+) (0.3 mm), and by the M-type K(+) current blockers linopirdine (150 microm) and XE991 (5 microm), and to enhancement by retigabine (10 microm), which increases opening of M-type K(+) channels. The OKC is suppressed by muscarine (30 microm) and is decreased by the L-type Ca(2+) channel blocker nifedipine (10 microm), but not by apamin (100 nm), which blocks SK-type Ca(2+)-dependent K(+) currents. Reverse transcriptase-polymerase chain reaction and immunocytochemical data suggest that MNCs express several members of the K(V)7 (KCNQ) family of K(+) channels, including K(V)7.2, 7.3, 7.4 and 7.5. Extracellular recordings of individual MNCs in a hypothalamic explant preparation demonstrated that an XE991- and retigabine-sensitive current contribute to the regulation of MNC firing. Our data suggest that the MNCs express an osmosensitive K(+) current that could contribute to the regulation of MNC firing by external osmolality and that could be mediated by K(V)7/M-type K(+) channels.