Author Correction: El Niño-Southern Oscillation complexity.

In this Review, the middle initial of author Kim M. Cobb was omitted. The original Review has been corrected online.

El Niño-Southern Oscillation complexity.

El Niño events are characterized by surface warming of the tropical Pacific Ocean and weakening of equatorial trade winds that occur every few years. Such conditions are accompanied by changes in atmospheric and oceanic circulation, affecting global climate, marine and terrestrial ecosystems, fisheries and human activities. The alternation of warm El Niño and cold La Niña conditions, referred to as the El Niño-Southern Oscillation (ENSO), represents the strongest year-to-year fluctuation of the global climate system. Here we provide a synopsis of our current understanding of the spatio-temporal complexity of this important climate mode and its influence on the Earth system.

7-day versus 14-day tegoprazan-based triple therapy to treat Helicobacter pylori infection: Real-world evidence.

BACKGROUND AND AIM: Potassium-competitive acid blockers (P-CABs) can be used to eradicate Helicobacter pylori infection. We aimed to evaluate the impact of treatment duration (7 vs 14 days) on successful H. pylori eradication with P-CAB-based triple therapy in Korea, where clarithromycin resistance rate is high. METHODS: We retrospectively reviewed the data of patients who received first-line treatment for H. pylori infection with tegoprazan-based triple therapy (50 mg tegoprazan + 1000 mg amoxicillin + 500 mg clarithromycin twice daily for 1 or 2 weeks). The primary endpoint was the eradication rate in intention-to-treat (ITT) analysis. RESULTS: Of the 948 patients included in the study, 435 and 513 received 7-day and 14-day tegoprazan-based triple therapy, respectively. The eradication rate was higher in the 14-day therapy group than in the 7-day therapy group (ITT, 63.9%; 95% confidence interval [CI], 59.3-68.3%] vs 78.6% [95% CI, 74.9-81.9%], respectively, P < 0.001; per-protocol, 70.5% [95% CI, 65.8-74.8%] vs 85.1% [81.7-88.1%], respectively, P < 0.001). Overall adverse event rates did not differ between the two groups. Although six patients in the 14-day treatment group discontinued the prescribed medications due to adverse events, four of them (67%) discontinued the medication within 4 days. CONCLUSIONS: The 14-day tegoprazan-based triple therapy showed a superior eradication rate and acceptable adverse events compared with the 7-day tegoprazan-based triple therapy. A 14-day treatment regimen may be required when H. pylori infection is treated with tegoprazan-based triple therapy in regions with high clarithromycin resistance.

A Randomized Controlled Trial Comparing Colonoscopic Enema With Additional Oral Preparation as a Salvage for Inadequate Bowel Cleansing Before Colonoscopy.

GOALS: The goal of this study was to evaluate the noninferiority of colonoscopic enema to additional oral preparation in salvage bowel cleansing for inadequate preparation for a morning colonoscopy. BACKGROUND: Colonoscopic enema, administering additional cathartics into the right colon through the colonoscope accessory channel, is suggested to rescue poor bowel preparation for a colonoscopy but lacking comparative study. STUDY: In this prospective, randomized, actively-controlled, parallel group, noninferiority trial, consecutive outpatients and health checkup recipients aged from 19 to 70 years with inappropriate bowel preparation during an elective colonoscopy were enrolled to receive either a colonoscopic enema of 1 L polyethylene glycol (PEG) (enema group) or additional oral intake of 2 L PEG (oral group). The primary endpoint was the proportion of adequate bowel preparation evaluated using the Boston Bowel Preparation Scale. RESULTS: Overall, 131 participants were randomized. Adequate bowel preparation was achieved in 53% (35/66) of the enema group, which was significantly inferior to the oral group (81.5%; 53/67) with a difference of -28.5% (95% confidence interval, -44.1, -12.9; P=0.001). The largest difference in the proportion of adequate bowel preparation was observed in the right colon (57.8% in the enema group vs. 86.9% in the oral group; P<0.001), followed by the transverse colon (85.9% vs. 98.4%; P=0.017) and the left colon (90.6% vs. 96.7%; P=0.274). CONCLUSIONS: The colonoscopic enema of 1 L PEG was inferior to the additional oral ingestion of 2 L PEG regarding efficacy as a salvage bowel preparation in adults with inadequate bowel cleansing for colonoscopy.

Mitochondrial E3 Ubiquitin Protein Ligase 1 Mediates Cigarette Smoke-Induced Endothelial Cell Death and Dysfunction.

By virtue of the critical roles of Akt in vascular endothelial cell (EC) survival and function, cigarette smoke-induced Akt reduction may contribute to EC death and dysfunction in smokers' lungs. One of the negative Akt regulatory mechanisms is K48-linked Akt ubiquitination and subsequent proteasomal degradation. Here, we assessed the involvement of mitochondrial E3 ubiquitin protein ligase 1 (MUL1), recently revealed as a novel Akt ubiquitin E3 ligase, in cigarette smoke-induced Akt ubiquitination and its contribution to pulmonary EC death and dysfunction. In human lung microvascular ECs (HLMVECs), cigarette smoke extract (CSE) noticeably elevated MUL1 expression and K48-linked Akt ubiquitination, whereas Akt, p-Akt, eNOS, and p-eNOS levels were decreased. MUL1 knockdown suppressed CSE-induced Akt ubiquitination/degradation and cytoplasmic reductions of Akt and p-Akt. Furthermore, MUL1 knockdown attenuated reductions of eNOS and p-eNOS and alleviated EC survival, migration, and tube formation in the presence of CSE exposure. In addition, overexpression of K284R Akt, a mutant for a MUL1-ubiquitination site, produced similar effects. In HLMVECs exposed to CSE, Akt-MUL1 interaction was increased in coimmunoprecipitation and in situ proximity ligation assays. Similarly, the proximity ligation assay signals were elevated in rat lungs exposed to cigarette smoke for 3 months, during which Mul1 levels were noticeably increased. Finally, we found that CSE-mediated MUL1 induction in HLMVECs is mediated by retinoic acid receptor-related orphan receptor α. Taken together, these data suggest that cigarette smoke-induced MUL1 elevation mediates Akt ubiquitination/degradation, potentially leading to pulmonary EC death and functional impairment.

Clinical predictors associated with proton pump inhibitor-induced hypomagnesemia.

There is increasing evidence and case reports regarding proton pump inhibitor (PPI)-induced hypomagnesemia. Our study aimed to clarify the relationship between PPI use and serum magnesium levels and to specify high-risk patients. We retrospectively studied 112 consecutive patients aged 20 years or older who were treated with PPI for ≥30 days and whose serum magnesium levels were available for the PPI treatment period. We compared the mean level of serum magnesium of the enrolled patients with PPI treatment with matched controls. There were no significant differences between the matched PPI users (n = 105) and nonusers (n = 210) in the magnesium levels (0.85 ± 0.09 vs. 0.86 ± 0.16 mM, P = 0.297). In a subgroup analysis of a PPI user group, hypomagnesemia could be observed in 32 patients but not in 80 patients. In multivariate analyses, PPI use for >1 year, age less than 45 years, and concurrent cisplatin or carboplatin use were significantly associated with PPI-induced hypomagnesemia {P = 0.042, odds ratio [OR; 95% confidence interval (CI)]: 5.388 [1.056-27.493]; P = 0.007, OR [95% CI]: 4.710 [1.523-14.571]; P = 0.007, OR [95% CI]: 13.404 [2.066-86.952], respectively} after adjusting for confounders. This study shows that long-term PPI use is associated with hypomagnesemia in hospitalized adult patients. Therefore, serum magnesium levels should be checked before the initiation of PPI treatment and during the treatment period in patients, particularly those concurrently using platinum-based chemotherapy or who are expected to use PPI for long periods.

Predictive Factors for Endoscopic Visibility and Strategies for Pre-endoscopic Prokinetics Use in Patients with Upper Gastrointestinal Bleeding.

BACKGROUND: Although current guideline recommends selective use of pre-endoscopic prokinetics to increase diagnostic yield in upper gastrointestinal bleeding (UGIB) patients, no data to guide the use of these drugs are available. AIMS: We aimed to investigate predictive factors for endoscopic visibility and develop simple and useful strategies for pre-endoscopic prokinetics use in UGIB patients. METHODS: A total of 220 consecutive patients who underwent upper endoscopy for suspicious UGIB were enrolled. Patients were randomly allocated to either a training or a validation set at a 2:1 ratio. Significant parameters on univariate analysis were subsequently tested by a classification and regression tree (CART) analysis. RESULTS: Time to endoscopy and nasogastric aspirate findings were independently related to endoscopic visibility. The CART analysis generated algorithms proposed sequential use of time to endoscopy (≤5.2 vs. >5.2 h) and nasogastric aspirate findings (red blood or coffee rounds vs. clear aspirate) for predicting endoscopic visibility. Prediction of unacceptable visibility in the validation set produced sensitivity, specificity, positive predictive value, and negative predictive value of 75.8, 67.5, 65.8, and 77.1 %, respectively. Accurate prediction for visibility was identified in 52 of 73 patients (71.2 %). CONCLUSIONS: Time to endoscopy and nasogastric aspirate findings were independently related to endoscopic visibility in patients with UGIB. A decision-tree model incorporating these two variables may be useful for selecting UGIB patients who benefit from pre-endoscopic prokinetics use.

Structures of D14 and D14L in the strigolactone and karrikin signaling pathways.

Strigolactones (SLs) are plant hormones that inhibit shoot branching. DWARF14 (D14) inhibits rice tillering and is an SL receptor candidate in the branching inhibition pathway, whereas the close homologue DWARF14-LIKE (D14L) participates in the signaling pathway of karrikins (KARs), which are derived from burnt vegetation as smoke stimulants of seed germination. We provide the first evidence for direct binding of the bioactive SL analogue GR24 to D14. Isothermal titration calorimetry measurements show a D14-GR24 binding affinity in the sub-micromolar range. Similarly, bioactive KAR1 directly binds D14L in the micromolar range. The crystal structure of rice D14 shows a compact α-/ß-fold hydrolase domain forming a deep ligand-binding pocket capable of accommodating GR24. Insertion of four α-helices between ß6 strand and αD helix forms the helical cap of the pocket, although the pocket is open to the solvent. The pocket contains the conserved catalytic triad Ser-His-Asp aligned with the oxyanion hole, suggesting hydrolase activity. Although these structural characteristics are conserved in D14L, the D14L pocket is smaller than that of D14. The KAR-insensitive mutation kai2-1 is located at the prominent long ß6-αD1 loop, which is characteristic in D14 and D14L, but not in related α-/ß-fold hydrolases.

Pre-treatment neutrophil to lymphocyte ratio as a prognostic marker to predict chemotherapeutic response and survival outcomes in metastatic advanced gastric cancer.

BACKGROUND: Several studies have shown that the neutrophil to lymphocyte ratio (NLR) in peripheral blood is a prognostic factor of various cancers. However, there is limited information on the clinical and prognostic significance of NLR in patients with metastatic advanced gastric cancer (AGC). Therefore, we examined whether the NLR can be used as a prognostic marker for predicting chemotherapeutic response and survival outcomes in metastatic AGC patients who are receiving palliative chemotherapy. METHOD: A total of 268 patients diagnosed with metastatic AGC were enrolled. NLR was calculated from complete blood cell count taken before the first chemotherapy treatment. Patients were divided into two groups according to the median value of NLR: a high NLR group and a low NLR group. RESULT: The median follow-up period was 340 days (range 72-1796 days) and median NLR was 3.06 (range 0.18-18.16). The high NLR group (NLR >3.0) contained 138 patients and the low NLR group (NLR ≤3.0) contained 130 patients. Low NLR group patients had a significantly higher chemotherapeutic disease control rate (90.0 % vs. 80.4; P = 0.028), and longer progression-free survival (PFS) and overall survival (OS) than the high NLR group patients (186 vs. 146 days; P = 0.001; 414 vs. 280 days; P < 0.001, respectively). In multivariate analysis, NLR showed a significant association with PFS (HR 1.478; 95 % CI 1.154-1.892; P = 0.002) and OS (HR 1.569; 95 % CI 1.227-2.006; P < 0.001). CONCLUSION: Pretreatment NLR is a useful prognostic marker in patients with metastatic AGC who are undergoing palliative chemotherapy.

Carcinomatosis matters: clinical outcomes and prognostic factors for clinical success of stent placement in malignant gastric outlet obstruction.

BACKGROUND: Although carcinomatosis is not a contraindication to stenting in selected patients with malignant gastric outlet obstruction (GOO), associate factors for clinical success rate of self-expandable metallic stent (SEMS) placement in GOO patients with carcinomatosis have not been fully characterized. METHODS: We analyzed a total 228 patients who were scheduled for SEMS placement for malignant GOO in tertiary-care academic medical center. All patients were treated with an uncovered or covered SEMS by using the over-the-wire placement procedure. We retrospectively evaluated clinical outcomes of SEMS placement. RESULTS: Technical success was achieved in all patients. Patients were categorized into two groups according to the presence of carcinomatosis. Clinical success rates of patients without carcinomatosis group and with carcinomatosis group were 93.9 % (92 of 98) and 80.8 % (105 of 130), respectively (P = 0.004). In subgroup analysis of patients with carcinomatosis, the clinical success rate was lower in patients with ascites (64.8 %) than in those without ascites (92.1 %, P < 0.001). Multivariate logistic regression model revealed that carcinomatosis without ascites did not decrease clinical success rate compared with absence of carcinomatosis; meanwhile, carcinomatosis with ascites showed lower clinical success rates compared with absence of carcinomatosis (adjusted odds ratio 0.163, 95 % confidence interval 0.058-0.461). In addition, poor performance status [Eastern Cooperative Oncology Group (ECOG) status ≥ 3, adjusted odds ratio 0.178, 95 % confidence interval 0.078-0.409] was also an independent poor predictive factor for clinical success of SEMS placement. CONCLUSIONS: In palliation for malignant GOO, the status of carcinomatosis with ascites and poor performance status (ECOG status ≥ 3) are significant predictive factors for poor clinical success of SEMS placement.

Safety and patient satisfaction of early diet after endoscopic submucosal dissection for gastric epithelial neoplasia: a prospective, randomized study.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a standard treatment for gastric neoplasia limited to the mucosa without lymph node metastasis. However, there are neither standardized guidelines nor studies on the best time to start oral intake after ESD. The aim of this study was to compare patient satisfaction, safety, length of hospital stay, and economic feasibility between an early post-ESD diet and the conventional immediate fasting protocol. METHODS: A total of 130 patients with 156 gastric epithelial neoplasias who underwent ESD by a single expert endoscopist were consecutively and prospectively enrolled. Enrolled patients were randomized to an early diet group or a control group. The early diet group started meals as a clear liquid diet on day 0, and a soft diet and general diet in sequence on day 1. The fasting group was fasted for 2 days. Patients in both groups underwent second-look endoscopy within 2 days following ESD and follow-up endoscopy after 2 months. RESULTS: In the course of the study, ten patients were excluded. The total number of patients in the early diet group and control group was 63 and 57, respectively. Mean age was 62 years (±9.4). There were no significant differences in clinicopathologic conditions or endoscopic results such as procedure time or size of lesions between the two groups. There were no significant differences in abdominal pain score, rate of post-ESD bleeding or healing rate of ESD-induced ulcer between the two groups. However, the early diet protocol led to significantly higher patient satisfaction (p = 0.001), lower hospital costs (p < 0.001), and shorter hospital stay (p < 0.001) than the conventional fasting protocol. CONCLUSIONS: An early post-ESD diet protocol provides higher patient satisfaction, is more cost effective, decreases hospital stay, and does not influence complication rates such as post-ESD bleeding, abdominal pain, or ulcer healing compared with the conventional fasting protocol.

Efficacy and Tolerability of 14-Day Tegoprazan- versus Rabeprazole-Based Triple Therapy for Eradication of Helicobacter pylori: A Real-World Evidence Study.

Background/Aims: Tegoprazan, a new, fast, and strong potassium-competitive acid blocker, has been approved for the treatment of gastric acid-related diseases in Korea. However, real-world clinical data regarding this drug are scarce. We aimed to compare the Helicobacter pylori eradication rates of tegoprazan- and rabeprazole-based triple therapy. Methods: We retrospectively reviewed data from patients who received first-line treatment for H. pylori infection using tegoprazan- or rabeprazole-based triple therapy for 2 weeks (50 mg tegoprazan or 20 mg rabeprazole+1,000 mg amoxicillin+500 mg clarithromycin twice daily). The primary endpoint was the eradication rate as determined by intention-to-treat analysis. Results: Of the 677 patients included in our study, 344 and 333 received tegoprazan-based and rabeprazole-based triple therapy, respectively. The eradication rate from intention-to-treat analysis was 76.7% (95% confidence interval [CI], 72.1% to 81.0%) for tegoprazan-based triple therapy and 75.4% (95% CI, 70.5% to 79.8%) for rabeprazole-based triple therapy. There was no significant difference in the eradication rates between the two groups (p>0.999). Per-protocol analysis also revealed no significant difference between the eradication rates of the two groups (tegoprazan 83.4% [95% CI, 79.0% to 87.2%] vs rabeprazole 83.5% [79.0% to 87.4%], p>0.999). Furthermore, there was no significant difference in adverse event rates between the two groups (tegoprazan, 27.6%; rabeprazole, 25.8%; p=0.604). Conclusions: The eradication rate of tegoprazan-based triple therapy was similar to that of rabeprazole-based triple therapy. Further studies on the dose-escalation effect of tegoprazan for H. pylori eradication and the efficacy of tegoprazan in regimens other than conventional triple therapy are needed.

Bortezomib alleviates experimental pulmonary arterial hypertension.

Vascular remodeling and endothelial dysfunction are important pathogenic features of pulmonary arterial hypertension (PAH). There is a growing body of evidence that proteasome inhibitors may be beneficial in vascular diseases by inhibiting proliferation of vascular smooth muscle cells (VSMCs) and ameliorating endothelial dysfunction. Here, we evaluated whether bortezomib (BTZ) could alleviate hypoxia- and monocrotaline (MCT)-induced PAH. BTZ (at doses from 1 to 100 µg/kg, or a dose of 100 µg/kg) was administered to mice every other day for the last 2 weeks of a 5-week hypoxia (10% O(2)) period, or to rats once daily from Day 22 to Day 34 after MCT challenge, respectively. BTZ treatment substantially suppressed elevation of right ventricular (RV) systolic pressure, RV hypertrophy, and pulmonary vascular remodeling in hypoxia-exposed mice. Similarly, BTZ treatment inhibited RV hypertrophy and vascular remodeling in MCT-injected rats. Strikingly, BTZ rescued 70% of MCT-injected rats up to Day 60, along with a considerable reduction in RV systolic pressure and suppression of vascular remodeling, whereas, among MCT-injected rats not administered BTZ, there were no survivors by Day 41. BTZ significantly suppressed proliferation of pulmonary VSMCs in vivo and in vitro. Furthermore, BTZ increased not only endothelial nitric oxide (NO) synthase (eNOS), phosphorylated eNOS, and NO production in vitro, but also eNOS and p-eNOS in hypoxia-exposed mice and MCT-injected rats, respectively. In contrast to the beneficial effects, BTZ increased active caspase-3 in cardiac ventricles of MCT-injected rats. Taken together, with caution for cardiotoxicity, BTZ could be a potential therapeutic strategy in PAH, possibly acting by inhibition of VSMC proliferation and amelioration of endothelial dysfunction.

Cigarette smoke induces Akt protein degradation by the ubiquitin-proteasome system.

Emphysema is one of the characteristic features of chronic obstructive pulmonary disease, which is caused mainly by cigarette smoking. Recent data have suggested that apoptosis and cell cycle arrest may contribute to the development of emphysema. In this study, we addressed the question of whether and how cigarette smoke affected Akt, which plays a critical role in cell survival and proliferation. In normal human lung fibroblasts, cigarette smoke extract (CSE) caused cell death, accompanying degradation of total and phosphorylated Akt (p-Akt), which was inhibited by MG132. CSE exposure resulted in preferential ubiquitination of the active Akt (myristoylated), rather than the inactive (T308A/S473A double mutant) Akt. Consistent with cytotoxicity, CSE induced a progressive decrease of phosphorylated human homolog of mouse double minute homolog 2 (p-HDM2) and phosphorylated apoptosis signal regulating kinase 1 (p-ASK1) with concomitant elevation of p53, p21, and phosphorylated p38 MAPK. Forced expression of the active Akt reduced both CSE-induced cytotoxicity and alteration in HDM2/p53/p21 and ASK1/p38 MAPK, compared with the inactive Akt. Of note, CSE induced expression of the tetratrico-peptide repeat domain 3 (TTC3), known as a ubiquitin ligase for active Akt. TTC3 siRNAs suppressed not only CSE-induced Akt degradation but also CSE-induced cytotoxicity. Accordingly, rat lungs exposed to cigarette smoke for 3 months showed elevated TTC3 expression and reduced Akt and p-Akt. Taken together, these data suggest that cigarette smoke induces cytotoxicity, partly through Akt degradation via the ubiquitin-proteasome system, in which TTC3 acts as a ubiquitin ligase for active Akt.

Mesenchymal stem cell-conditioned media recovers lung fibroblasts from cigarette smoke-induced damage.

Cigarette smoking causes apoptotic death, senescence, and impairment of repair functions in lung fibroblasts, which maintain the integrity of alveolar structure by producing extracellular matrix (ECM) proteins. Therefore, recovery of lung fibroblasts from cigarette smoke-induced damage may be crucial in regeneration of emphysematous lung resulting from degradation of ECM proteins and subsequent loss of alveolar cells. Recently, we reported that bone marrow-derived mesenchymal stem cell-conditioned media (MSC-CM) led to angiogenesis and regeneration of lung damaged by cigarette smoke. In this study, to further investigate reparative mechanisms for MSC-CM-mediated lung repair, we attempted to determine whether MSC-CM can recover lung fibroblasts from cigarette smoke-induced damage. In lung fibroblasts exposed to cigarette smoke extract (CSE), MSC-CM, not only inhibited apoptotic death, but also induced cell proliferation and reversed CSE-induced changes in the levels of caspase-3, p53, p21, p27, Akt, and p-Akt. MSC-CM also restored expression of ECM proteins and collagen gel contraction while suppressing CSE-induced expression of cyclooxygenase-2 and microsomal PGE(2) synthase-2. The CSE-opposing effects of MSC-CM on cell fate, expression of ECM proteins, and collagen gel contraction were partially inhibited by LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor. In rats, MSC-CM administration also resulted in elevation of p-Akt and restored proliferation of lung fibroblasts, which was suppressed by exposure to cigarette smoke. Taken together, these data suggest that MSC-CM may recover lung fibroblasts from cigarette smoke-induced damage, possibly through inhibition of apoptosis, induction of proliferation, and restoration of lung fibroblast repair function, which are mediated in part by the PI3K/Akt pathway.

Efficacy of entecavir and adefovir combination therapy for patients with lamivudine- and entecavir-resistant chronic hepatitis B.

BACKGROUND: The optimal treatment of patients with chronic hepatitis B (CHB) who develop resistance to both lamivudine (LMV) and entecavir (ETV) after sequential monotherapy of LMV and ETV remains little known. METHODS: We evaluated the efficacy of entecavir (ETV) plus adefovir dipivoxil (ADV) combination therapy for patients with resistance to LMV and ETV. We reviewed the medical records of 12 patients, and treated all 12 patients with ETV plus ADV combination therapy for at least 18 months. Quantitative hepatitis B virus (HBV) DNA levels, serologic markers, and hepatic panel values were monitored at baseline and 3-month intervals thereafter for 18 months. RESULTS: The baseline mean serum HBV DNA level was 7.26 ± 1.11 log(10) copies/ml. The mean reductions in serum HBV DNA levels from baseline to 3, 6, 9, 12, 15, and 18 months were -1.98 ± 1.03, -2.87 ± 1.02, -3.32 ± 1.10, -3.92 ± 1.30, -4.36 ± 1.22, and -4.57 ± 1.18 log(10) copies/ml, respectively. Complete virological response (HBV DNA of <2 log(10) copies/ml) at 6, 12, and 18 months was observed in 1 (8.3%), 4 (33.3%), and 6 (50.0%) patients, respectively. The 2 patients with baseline HBV DNA of <6 log(10) copies/ml achieved complete virological response at 18 months, while 4 of 10 patients with baseline HBV DNA of ≥6 log(10) copies/ml achieved complete virological response at 18 months. None of the 12 patients experienced virological breakthrough during follow-up. CONCLUSIONS: ETV plus ADV combination therapy effectively reduced serum HBV DNA levels in patients with CHB who developed resistance to both LMV and ETV. Additional long-term studies are needed to assess the effect of long-term treatment with these drugs.

Tropical origins of the record-breaking 2020 summer rainfall extremes in East Asia.

The East Asian countries have experienced heavy rainfalls in boreal summer 2020. Here, we investigate the dynamical processes driving the rainfall extremes in East Asia during July and August. The Indian Ocean basin warming in June can be responsible for the anticyclonic anomalies in the western North Pacific (WNP), which modulate the zonally-elongated rainfalls in East Asia during July through an atmospheric Rossby wave train. In August, the East Asian rainfall increase is also related to the anticyclonic anomalies in the subtropical WNP, although it is located further north. The north tropical Atlantic warming in June partly contributes to the subtropical WNP rainfall decrease in August through a subtropical teleconnection. Then the subtropical WNP rainfall decrease drives the local anticyclonic anomalies that cause the rainfall increase in East Asia during August. The tropical Indian Ocean anomalously warmed in June and the subtropical WNP rainfall decreased in August 2020, which played a role in modulating the WNP anticyclonic anomalies. Therefore, the record-breaking rainfall extremes in East Asia that occurred during summer 2020 can be explained by the teleconnections associated with the tropical origins among the Indian, Pacific, and Atlantic Oceans and their interbasin interactions.

Characterization of an (R)-specific enoyl-CoA hydratase from Streptomyces sp. strain CFMR 7: A metabolic tool for enhancing the production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate).

Poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] has a high potential to serve as a commercial bioplastic due to its biodegradability, thermoplastic and mechanical properties. The properties of this copolymer are greatly affected by the composition of 3HHx monomer. One of the most efficient ways to modulate the composition of 3HHx monomer in P(3HB-co-3HHx) is by manipulating the (R)-3HHx-CoA monomer supply. In this study, a new (R)-specific enoyl-CoA hydratase originating from a non-PHA producer, Streptomyces sp. strain CFMR 7 (PhaJSs), was characterized and found to be effective in supplying 3HHx monomer during in vivo production of P(3HB-co-3HHx) copolymer. The P(3HB-co-3HHx) copolymer produced from the Cupriavidus necator transformant that harbors phaJSs, PHB-4/pBBR1-CBP-M-CPF4JSs, showed enhanced 3HHx incorporation of up to 11 mol% without affecting the P(3HB-co-3HHx) production when palm oil was used as the carbon source. In addition, both kcat and kcat/Km of PhaJSs were higher toward the C6 than the shorter C4 substrates, underscoring the preference for 3-hydroxyhexanoyl-CoA. These results suggest that PhaJSs has a significant ability to supply 3HHx monomers for PHA biosynthesis via ß-oxidation and can be applied for metabolic engineering of robust PHA-producing strains.

Bone marrow cells repair cigarette smoke-induced emphysema in rats.

The therapeutic potential of stem cells in chronic obstructive pulmonary disease is not well known although stem cell therapy is effective in models of other pulmonary diseases. We tested the capacities of bone marrow cells (BMCs), mesenchymal stem cells (MSCs), and conditioned media of MSCs (MSC-CM) to repair cigarette smoke-induced emphysema. Inbred female Lewis rats were exposed to cigarette smoke for 6 mo and then received BMCs, MSCs, or MSC-CM from male Lewis rats. For 2 mo after injection, the BMC treatment gradually alleviated the cigarette smoke-induced emphysema and restored the increased mean linear intercept. The BMC treatment significantly increased cell proliferation and the number of small pulmonary vessels, reduced apoptotic cell death, attenuated the mean pulmonary arterial pressure, and inhibited muscularization in small pulmonary vessels. However, only a few male donor cells were detected from 1 day to 1 mo after BMC administration. The MSCs and cell-free MSC-CM also induced the repair of emphysema and increased the number of small pulmonary vessels. Our data show that BMC, MSCs, and MSC-CM treatment repaired cigarette smoke-induced emphysema. The repair activity of these treatments is consistent with a paracrine effect rather than stem cell engraftment because most of the donor cells disappeared and because cell-free MSC-CM also induced the repair.

YC-1 attenuates hypoxia-induced pulmonary arterial hypertension in mice.

BACKGROUND: Pulmonary arterial hypertension (PAH) is characterized by a progressive increase in pulmonary vascular resistance and elevation of pulmonary arterial pressure, leading to right ventricular failure and eventual death. Currently, no curative therapy for PAH is available, and the overall prognosis is very poor. Recently, direct activators of soluble guanylyl cyclase (sGC) have been tested as a novel therapeutic modality in experimental models of pulmonary arterial hypertension (PAH). OBJECTIVE: In this study, we used in vitro and in vivo models to evaluate the therapeutic potential of 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1), a dual functioning chemical, as a direct activator of guanylyl cyclase and an inhibitor of hypoxia-inducible factor-1. METHODS: We analyzed the effects of YC-1 on cell proliferation and the levels of p21 and p53 in human pulmonary artery smooth muscle cells (HPASMCs) under hypoxia. We also determined the effects of YC-1 on expression of endothelin-1 (ET-1) and phosphorylation status of endothelial nitric oxide synthase (eNOS) at Ser(1179) in human pulmonary artery endothelial cells (HPAECs) under hypoxia. In mice, hypoxic PAH was induced by exposure to normobaric hypoxic conditions for 28 days. To assess preventive or therapeutic effects, randomized mice were subjected to once daily i.p. injections of YC-1 for the entire hypoxic period (5 mg/kg) or for the last seven days of a 28-day hypoxic period (5 and 10 mg/kg). On day 28, we measured the right ventricular systolic pressure (RVSP) and determined the degrees of right ventricular hypertrophy (RVH) and vascular remodeling. RESULTS: In HPASMCs, YC-1 inhibited hypoxia-induced proliferation and induction of p53 and p21 in a concentration-dependent manner. Also, YC-1 suppressed the hypoxia-induced expression of ET-1 mRNA and dephosphorylation of eNOS at Ser(1179) in HPAECs. In the preventive in vivo model, a daily dose of 5 mg/kg YC-1 significantly prevented the elevation of RVSP, development of RVH, and pulmonary vascular remodeling, which were caused by hypoxic exposure. In the therapeutic model, YC-1 at daily doses of 5 and 10 mg/kg alleviated RVH and pulmonary vascular remodeling but did not prevent the elevation of RVSP. CONCLUSIONS: Our results indicate that YC-1 prevents the development of hypoxia-induced PAH in a preventive model and alleviates RVH and pulmonary vascular remodeling in a therapeutic model. Therefore, these data imply that YC-1 has therapeutic potential for use in a single or combination therapy for PAH.