Application of Carbon Nanoparticles in Transoral Endoscopic Thyroidectomy Vestibular Approach for Unilateral Papillary Thyroid Cancer.

BACKGROUND: Transoral endoscopic thyroidectomy vestibular approach (TOETVA) is newly applied technology. Carbon nanoparticles (CNs) are novel lymph node tracers that have been widely used in China to help remove central lymph nodes (CLNs) and protect the parathyroid glands (PGs) in open thyroid cancer surgery. This study is to evaluate the effectiveness and safety of CNs in TOETVA. MATERIALS AND METHODS: A total of 158 patients who underwent TOETVA with unilateral papillary thyroid carcinoma were enrolled in this study from March 2019 to February 2022. The participants were divided into a CNs group (n=88) and a control group (n=70), based on whether they received a intraoperative injection of CNs or not. Meanwhile, the CNs group were additionally divided into 2 subgroups, leakage subgroup (n=26) and standard subgroup (n=62). The 2 groups and subgroups were compared in terms of patient characteristics, perioperative clinical results, and postoperative outcomes. RESULTS: All common metrics had no significant differences were found between the CNs group and the control group (P>0.05). The standard subgroup of CNs group had advantage over the control group on PGs identification (59/62 vs. 59/70 for superior PG, 56/62 vs. 52/70 for inferior PG, P<0.05). Moreover, the standard subgroup harvested more CLNs than the control group (8.97±2.96 vs. 7.47±2.93, P<0.05). More operation time was spent on the leakage subgroup of CNs group than the control group (160.00±17.61 vs. 140.00±13.32, P<0.05). Meanwhile, the leakage subgroup had disadvantage on intraoperative hemorrhage (26.15±10.80 vs. 21.21±7.09, P<0.05) and hospital durations (4.96±0.72 vs. 4.57±0.69, P<0.05). Furthermore, the leakage group identified fewer inferior PG than the control group (7/26 vs. 52/70, P<0.05). Contrary to the standard subgroup, the CLNs of the leakage subgroup was also unsatisfactory compared with the control group (4.96±1.84 vs. 7.47±2.93, P<0.05). CONCLUSIONS: The application of CNs suspension tracing technology has a definite effect in TOETVA. It can improve the thoroughness of lymph node dissection in the central region and enhance recognition of the PG. However, refined extracapsular anatomy is indispensable to prevent CN leakage. Leaked CNs will also be counterproductive to the operation.

Sodium Carbonate-Promoted Formation of 5-Amino-1,2,4-thiadiazoles and 5-Amino-1,2,4-selenadiazoles with Elemental Sulfur and Selenium.

Sodium carbonate-promoted facile synthesis of 5-amino-1,2,4-thiadiazoles and 5-amino-1,2,4-selenadiazoles with elemental sulfur and selenium, respectively, was developed. This method was carried out with O2 in the air as the green oxidant, and it has several advantages, including low cost, low toxicity, and stable sulfur and selenium sources, good to excellent yields with water as the sole byproduct, simple operation, and a broad substrate scope. Preliminary mechanistic studies indicate that the formation of the 1,2,4-thiadiazole ring and the 1,2,4-selenadiazole ring undergoes different processes.

Electrochemically Promoted Three-Component Reaction to N-Sulfonyl Amidines.

In this study, a multicomponent reaction via the Mannich intermediate was developed using methanol, secondary amine, and sulfonamide as starting materials. This method uses methanol as a green C1 source. The substrate scope is wide, and the yield is good. The mechanistic study shows that methanol generates formaldehyde under electrochemical conditions, and sulfonyl amidine as a nucleophile reacts with Schiff base intermediates to form N-sulfonyl amidine in a single step.

Efficacy of ß2-adrenergic receptor agonist combined with corticosteroid in the treatment of children with cough variant asthma.

BACKGROUND: Cough variant asthma (CVA) is one of the most common respiratory diseases in children, which has a serious impact on the quality of life and daily activities of children. For severe CVA, immunomodulatory drugs are needed. AIM: To evaluate the efficacy of salmeterol combined with budesonide in the treatment of pediatric CVA. METHODS: 130 children with CVA from January 2020 to December 2022 were prospectively selected and randomly divided into an observation group (salmeterol combined with budesonide) and a control group (budesonide combined with a placebo). Compare the clinical efficacy of two groups before and after intervention. The evaluation parameters include cough frequency score, nocturnal cough arousal, and lung function indicators. Serum inflammatory markers, immune function markers and airway anatomical indicators were also measured. RESULTS: After the intervention, the total effective rate of the observation group was significantly higher than that of the control group, and the cough frequency score and the night cough wake rate of the observation group were lower than that of the control group, with a statistically significant difference. In addition, the changes of lung function indicators, serum markers and immune function markers in the observation group were better than those in the control group. CONCLUSION: The clinical efficacy of salmeterol combined with Budesonide in the treatment of CVA is better than that of Budesonide alone.

Transoral Endoscopic Thyroidectomy Vestibular Approach Versus Gasless Transaxillary Endoscopic Thyroidectomy for Patients With Unilateral Papillary Thyroid Carcinoma: A Retrospective Study.

BACKGROUND: Transoral endoscopic thyroidectomy vestibular approach (TOETVA) and gasless transaxillary endoscopic thyroidectomy (GTET) are 2 newly applied technologies. This study is to compare the 2 approaches from the aspects of effectiveness and safety. MATERIALS AND METHODS: A total of 339 patients who underwent TOETVA or GTET with unilateral papillary thyroid carcinoma were enrolled in this study from March 2019 to February 2022. The 2 groups were compared in terms of patient characteristics, perioperative clinical results, and postoperative outcomes. RESULTS: The operative time of the TOETVA group was significantly longer than the GTET group (141.39±16.11 vs. 98.45±12.24, P <0.05). The TOETVA group had advantages over GTET group when the reduction of parathyroid hormone was compared (19.18±17.43 vs. 23.07±15.72, P <0.05). Meanwhile, more parathyroids were detected in central neck specimens in GTET group (40/181 vs. 21/158, P <0.05). TOETVA had an advantage on total number of central lymph nodes over GTET (7.65±3.11 vs. 4.99±2.45, P <0.05), whereas the number of positive central lymph nodes was similar ( P >0.05). No differences were found between the 2 groups on other data. CONCLUSIONS: TOETVA and GTET are both safe and effective for unilateral papillary thyroid carcinomas. TOETVA has advantage on protection of inferior parathyroid glands and harvest of central lymph node dissection. Meanwhile, GTET can save more time compared with TOETVA. Surgeons and patients should freely choose the approaches based on their demands.

Electrocatalytic ring-opening dihydroalkoxylation of N-aryl maleimides with alcohols under metal- and oxidant-free conditions.

The electrocatalytic ring-opening dihydroalkoxylation of N-aryl maleimides with alcohols under metal- and oxidant-free conditions is described. This electrochemical process consists of anodic single-electron transfer oxidation, cathodic radical reduction, rearrangement-ring cleavage and nucleophilic addition cascade, which employs tetrabutylammonium bromide not only as a redox catalyst but also as an efficient supporting electrolyte, and offers a practical and environmentally friendly route to ring-opening difunctionalization products.

Three-Component Domino Reaction of Thioamide, Isonitriles, and Water: Selective Synthesis of 1,2,4-Thiadiazolidin-3-ones and (E)-N-(1,2-Diamino-2-thioxoethylidene)benzamides.

The three-component domino reaction of thioamides, benzyl isocyanide, and water in the presence of a catalytic amount of both Pd(dppf)Cl2 and Cu(OAc)2 afforded novel 1,2,4-thiadiazolidin-3-one cyclic compounds, whereas the same reaction with tertiary alkylisonitriles in the presence of rare earth metal salt [La(OTf)3] resulted in (E)-N-(1,2-diamino-2-thioxoethylidene)benzamide open-chain products. This divergent reaction enabled the one-pot construction of five (N-S, C-S, C-O, and two C-N) or four (C-S, C-N, C-O, and C-C) new chemical bonds. Mechanism studies indicate that the oxygen atom of the product was derived from H2O.

Epidemiological characteristics of hand, foot and mouth disease in Nanping City, Fujian Province from 2012 to 2021 / 中国热带医学

@#Abstract: Objective　To analyze the epidemic characteristics of hand, foot and mouth disease (HFMD) in Nanping City, Fujian province and to provide the basis for formulating effective prevention and control measures as well as evaluating the efficacy of prevention and treatment. Methods　Descriptive epidemiological method was used to analyze the incidence data of HFMD in Nanping City from 2012 to 2021. Results　A total of 49 231 cases of HFMD were reported in Nanping City from 2012 to 2021. The incidence fluctuated greatly over the 10-year period, ranging from 76.10/100 000 to 308.93/100 000, with an average incidence of 184.99/100 000 per year. The overall incidence and the number of cases showed a fluctuating downward trend over time, but the incidence was high in the next year, and there were statistically significant differences in the incidence rates between different years(χ2=8 169.176, P<0.001). There were significant regional differences in the incidence, the top three average annual incidence rates were: Guanze County (370.76/100 000), Zhenghe County (295.31/100 000) and Wuyishan City (250.31/100 000). There were two peaks of HFMD incidence each year, with the first occurring in May and June and the second occurring in September and October. The incidence rate was higher among males (215.86/100 000) than females (152.93/100 000), and males were more susceptible than females (RR=1.412, 95%CI=1.387-1.438). The cases were mainly aged 0-4 years, accounting for 86.25% (42 461/49 231) of all cases, and the incidence rate gradually decreased with increasing age (χ2trend=570,105.801, P<0.001). The majority of cases (85.22%, 41 953/49 231) occurred in children living in scattered areas, followed by children in kindergartens (12.39%, 6 101/49 231). The etiological results showed a total of 3 476 laboratory-confirmed cases, and the proportion of three (classes) of enterovirus positivity varied each year, with different pathogen compositions showing statistical significance (χ2=584.613, P<0.001). In addition to the years 2015-2017, during which Cox A16 and EV71 were the dominant strains, other years were dominated by other enteroviruses, with EV71 being the main type in severe and fatal cases of HFMD in Nanping City. Conclusion　Nanping City should strengthen health education for children living in the diaspora and in day-care centers, enhance surveillance of epidemics and pathogenology, improve vaccination rates against EV71, focus on the detection and typing of other enteroviruses, and implement effective prevention and control measures for HFMD.

Electrochemically Mediated Carboxylative Cyclization of Allylic/Homoallylic Amines with CO2 at Ambient Pressure.

CO2 is an important C1 resource. We report a method for the synthesis of pharmacologically active 2-oxazolidinones by reacting CO2 with allylic amines. As opposed to previous addition reactions, the unsaturated double bonds are preserved. Thus, the product is more plastic and easier to use for subsequent structural modification. Furthermore, this method can also be applied to the synthesis of six-membered heterocycles (1,3-oxazinan-2-ones) and the participation of a low concentration of CO2, indicating it has certain practicability.

The Role of Autophagy in Osteoarthritic Cartilage.

Osteoarthritis (OA) is one of the most common diseases leading to physical disability, with age being the main risk factor, and degeneration of articular cartilage is the main focus for the pathogenesis of OA. Autophagy is a crucial intracellular homeostasis system recycling flawed macromolecules and cellular organelles to sustain the metabolism of cells. Growing evidences have revealed that autophagy is chondroprotective by regulating apoptosis and repairing the function of damaged chondrocytes. Then, OA is related to autophagy depending on different stages and models. In this review, we discuss the character of autophagy in OA and the process of the autophagy pathway, which can be modulated by some drugs, key molecules and non-coding RNAs (microRNAs, long non-coding RNAs and circular RNAs). More in-depth investigations of autophagy are needed to find therapeutic targets or diagnostic biomarkers through in vitro and in vivo situations, making autophagy a more effective way for OA treatment in the future. The aim of this review is to introduce the concept of autophagy and make readers realize its impact on OA. The database we searched in is PubMed and we used the keywords listed below to find appropriate article resources.

Aerobic Copper-Catalyzed Four-Component Reaction of O-Phenylenediamines, Isocyanides, and Selenium Powder for the Assembly of Benzo[4,5]imidazo[2,1-c][1,2,4]selenadiazol-3-imine Derivatives.

A convenient, four-component reaction of o-phenylenediamines, isocyanides, and selenium powder catalyzed by a natural abundant copper/air (O2) catalyst system has been developed, providing a highly step and atom economical protocol for the synthesis of benzo[4,5]imidazo[2,1-c][1,2,4]selenadiazol-3-imine derivatives with excellent yields and good functional group tolerance. This method enables the construction of an imidazo[2,1-c][1,2,4]selenadiazol ring, one N-Se bond, one C-Se bond, and three C-N bonds in a single step with only water as the byproduct. Preliminary mechanistic studies imply that the copper/air (O2)-catalyzed cyclization proceeds via a selenium-centered radical intermediate.

Comparing the Efficacy of Intra-Articular Single Platelet-Rich Plasma(PRP) versus Novel Crosslinked Hyaluronic Acid for Early-Stage Knee Osteoarthritis: A Prospective, Double-Blind, Randomized Controlled Trial.

Background and Objectives: For the treatment of knee osteoarthritis (OA), intra-articular platelet-rich plasma (PRP) and novel crosslinked single-dose hyaluronic acid (HA) have both been reported to improve outcomes, but no study has compared them for the treatment of knee OA. We hypothesized patients with early-stage knee OA who received PRP injections would have more WOMAC score changes than those who received HA injections. This is the first prospective, double-blind, parallel, randomized controlled trial comparing the efficacy of intra-articular single-dose PRP versus novel crosslinked HA (HyajointPlus) for treating early-stage knee OA. Materials and Methods: This study analyzed 110 patients randomized into the PRP (n = 54) or HA (n = 56) groups. The primary outcome is the change of WOMAC score at 1-, 3-, and 6-month follow-ups compared to baseline. Results: The data revealed significant improvements in all WOMAC scores in the PRP group at 1-, 3-, and 6-month follow-up visits compared with the baseline level except for the WOMAC stiffness score at the 1-month follow up. In the HA group, significant improvements were observed only in the WOMAC pain score for all the follow-up visits and in WOMAC stiffness, function, and total scores at 6-month follow-up. When comparing the change of WOMAC score at 1-, 3-, and 6-month follow-ups, no significant differences were found between PRP and HA group. Conclusions: This study revealed that both PRP and HA can yield significant improvements in WOMAC scores at 6-month follow-up without any between-group differences at 1-, 3-, and 6-month follow-ups. Thus, both the single-injection regimens of PRP and HA can improve the functional outcomes for treating early-stage knee OA.

Scaling-up and proteomic analysis reveals photosynthetic and metabolic insights toward prolonged H2 photoproduction in Chlamydomonas hpm91 mutant lacking proton gradient regulation 5 (PGR5).

Clean and sustainable H2 production is crucial to a carbon-neutral world. H2 generation by Chlamydomonas reinhardtii is an attractive approach for solar-H2 from H2O. However, it is currently not large-scalable because of lacking desirable strains with both optimal H2 productivity and sufficient knowledge of underlying molecular mechanism. We hereby carried out extensive and in-depth investigations of H2 photoproduction of hpm91 mutant lacking PGR5 (Proton Gradient Regulation 5) toward its up-scaling and fundamental mechanism issues. We show that hpm91 is at least 100-fold scalable (up to 10 L) with continuous H2 collection of 7287 ml H2/10L-HPBR in averagely 26 days under sulfur deprivation. Also, we show that hpm91 is robust and active during sustained H2 photoproduction, most likely due to decreased intracellular ROS relative to wild type. Moreover, we obtained quantitative proteomic profiles of wild type and hpm91 at four representing time points of H2 evolution, leading to 2229 and 1350 differentially expressed proteins, respectively. Compared to wild type, major proteome alterations of hpm91 include not only core subunits of photosystems and those related to anti-oxidative responses but also essential proteins in photosynthetic antenna, C/N metabolic balance, and sulfur assimilation toward both cysteine biosynthesis and sulfation of metabolites during sulfur-deprived H2 production. These results reveal not only new insights of cellular and molecular basis of enhanced H2 production in hpm91 but also provide additional candidate gene targets and modules for further genetic modifications and/or in artificial photosynthesis mimics toward basic and applied research aiming at advancing solar-H2 technology.

The Role of Mitochondrial Metabolism, AMPK-SIRT Mediated Pathway, LncRNA and MicroRNA in Osteoarthritis.

Osteoarthritis (OA) is the most common joint disease characterized by degeneration of articular cartilage and causes severe joint pain, physical disability, and impaired quality of life. Recently, it was found that mitochondria not only act as a powerhouse of cells that provide energy for cellular metabolism, but are also involved in crucial pathways responsible for maintaining chondrocyte physiology. Therefore, a growing amount of evidence emphasizes that impairment of mitochondrial function is associated with OA pathogenesis; however, the exact mechanism is not well known. Moreover, the AMP-activated protein kinase (AMPK)-Sirtuin (SIRT) signaling pathway, long non-coding RNA (lncRNA), and microRNA (miRNA) are important for regulating the physiological and pathological processes of chondrocytes, indicating that these may be targets for OA treatment. In this review, we first focus on the importance of mitochondria metabolic dysregulation related to OA. Then, we show recent evidence on the AMPK-SIRT mediated pathway associated with OA pathogenesis and potential treatment options. Finally, we discuss current research into the effects of lncRNA and miRNA on OA progression or inhibition.

Effects of 15-Days -6° Head-Down Bed Rest on the Attention Bias of Threatening Stimulus.

Previous researchers have found that head-down bed rest (HDBR) will affect the emotional state of individuals, and negative emotions such as anxiety are closely related to attention bias. The present study adopted the dot-probe task to evaluate the effects of 15-days of -6° HDBR on the attention bias of threatening stimulus in 17 young men, which was completed before (Pre-HDBR), during (HDBR-1, HDBR-8, HDBR-15), after (Post-HDBR) the bed rest. In addition, self-report inventories (State Anxiety Inventory, SAI; Positive Affect and Negative Affect Scale, PANAS) were conducted to record emotional changes. The results showed that the participants' negative affect scores on HDBR-8 were significantly lower than the HDBR-1 in PANAS while there was no significant difference on positive affect scores and anxiety scores in SAI. And the results showed that at the Pre-HDBR, HDBT-1, HDBR-15, Post-HDBR, the response speed to threatening stimulus was faster than neutral stimulus, but no statistical significance. However, reaction time of threatening stimulus is significantly longer than neutral stimulus in the HDBR-8, indicating that HDBR may have an effect on the participants' attention bias, and this effect is manifested as attention avoidance.

[Effects of Obstructive Sleep Apnea and Gender on Glomerular Filtration Rate in Hypertensive Population].

Objective To explore the associations of obstructive sleep apnea(OSA) and gender with estimated glomerular filtration rate(eGFR) in hypertensive populations.Methods From February 2005 to August 2010,2064 hypertensive patients who were treated in the Department of Hypertension Center underwent overnight polysomnographic monitoring.According to the apnea-hypopnea index(AHI),they were assigned into an hypertension combined with OSA group and a hypertension group.The clinical characteristics and sleep monitoring indicators were compared between different genders and between the two groups.Multivariate Logistic regression was employed to analyze the influencing factors of eGFR.Results Among the 2064 hypertensive patients,there were 1537 males(including 1221 patients with OSA) and 527 females(including 350 patients with OSA).The males had higher prevalence of OSA(χ2=36.631,P<0.001) and diastolic blood pressure(Z=-7.776,P<0.001) and lower eGFR(Z=-3.010,P=0.003) than the females.The males had higher AHI(Z=-8.727,P<0.001),apnea index(Z=-9.252,P<0.001),hypopnea index(HI)(Z=-4.868,P<0.001) than the females,and the lowest oxygen saturation(t=-3.325,P=0.001) was significantly lower in males than in females.The hypertension combined with OSA group showed lower eGFR than the hypertension group(Z=-27.434,P<0.001;Z=-18.762,P<0.001).HI was negatively correlated with eGFR in the male population(r=-0.006,P=0.017),and AHI and HI were negatively correlated eGFR in females(r=-0.108,P=0.013;r=-0.094,P=0.032).After adjustment,Logistic regression showed that OSA and oxygen desaturation index 4 were the risk factors for the reduction of eGFR in hypertensive patients in males and females,respectively(OR=1.383,95%CI=1.010-1.905,P=0.045;OR=1.013,95%CI=1.002-1.024,P=0.021).Conclusion OSA lowers the eGFR of hypertensive patients,and OSA and oxygen desaturation index are the risk factors for the decrease in eGFR in male and female hypertensive patients,respectively.

MnSO4-promoted S-O bond cleavage for synthesizing functionalized sulfonium ylides from activated alkynes and sulfoxides.

A variety of functionalized sulfonium ylides were prepared in good yields through MnSO4-promoted S-O bond cleavage from activated alkynes and sulfoxides. Experimental results showed that the MnSO4 catalyst played important roles in accelerating the reaction and promoting the [1,3]-rearrangement of the S-O bond. Furthermore, the product was easily obtained on a gram scale by simple recrystallization without column chromatography. The obtained product can be converted to new sulfonium ylides and undergo cycloaddition with an alkyne to afford a trisubstituted furan scaffold.

Efficacy of Intra-Articular Injection of Biofermentation-Derived High-Molecular Hyaluronic Acid in Knee Osteoarthritis: An Ultrasonographic Study.

OBJECTIVE: The aim of this study is to evaluate the efficacy of intra-articular injection with HYAJOINT Plus, a biofermentation-derived, high-molecular hyaluronic acid (HA), on the progression of structural changes of cartilage in patients with knee osteoarthritis (OA) by using objectively promised ultrasonography (US) evaluation. DESIGN: In this prospective clinical trial, 56 OA patients completed the study. One single dose of injection of HYAJOINT Plus into the knee cavity was performed. The primary efficacy outcome measure for structural change of knee joint was evaluated by US using a semiquantitative grading system. Secondary efficacy outcome measures included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total and subscale scores. All efficacy outcomes were measured at baseline and at first, third, and sixth month following treatment. RESULTS: There were significant US grade-improvement changes of cartilage between baseline and follow-up visits over medial femoral condyle and transverse overall evaluation at 3- and 6-month follow-ups, and over lateral femoral condyle, intercondylar notch, and medial longitudinal area at 6-month follow-up. The improved score change of WOMAC from baseline was significant at 1- and 3-month follow-ups in pain subscale, whereas score change from baseline was significant at 6-month follow-up in total score and all 3 subscale scores. CONCLUSIONS: It was determined that significant improvement was found on cartilage by US after intra-articular injection with high-molecular weight, biological fermentation-derived HYAJOINT Plus. The semiquantitative grading system by US is a promising tool to identify the efficacy on cartilage band after interventions.

Molecular Weight of Hyaluronic Acid Has Major Influence on Its Efficacy and Safety for Viscosupplementation in Hip Osteoarthritis: A Systematic Review and Meta-Analysis.

BACKGROUND: This study aimed to compare the efficacy and safety of intra-articular hyaluronic acid (HA) injection with different molecular weights (MWs) for treating hip osteoarthritis (OA). METHODS: A systematic literature search for relevant studies was conducted in 3 electronic databases, including PubMed, BMJ Journals, and Cochrane Library, from inception to April 2020. Extracted outcomes included visual analogue scale (VAS) (1, 3, and 6 months), Lequesne index (3 and 6 months), and adverse effects. HAs were classified into low-molecular-weight (LMW), moderate-molecular-weight (MMW), high-molecular-weight (HMW), and ultra-high-molecular-weight (UHMW) groups. Meta-analysis was performed using Review Manager 5.3. RESULTS: A total of 15 studies with 614 patients were included. Our meta-analysis showed that the HMW HA group had the best improvement in VAS and Lequesne index compared with other HA groups for all the follow-up visits. Moreover, the HMW group demonstrated significantly better improvement than the other groups in VAS at 6-month follow-up and in Lequesne index at 3- and 6-month follow-ups. Analysis for adverse effects revealed low rates of systemic adverse effects (≤0.6%) in all groups and similar rate of local adverse effects (around 10%) among the groups except for UHMW HA group (37.5%). CONCLUSION: Among different MWs of HA for treating hip OA, HMW HA injection demonstrated the best efficacy for up to 6 months after treatment without increased risk of adverse effects. Further studies with more comprehensive data and a higher level of evidence are required to prove our results.

Structure and activity of SLAC1 channels for stomatal signaling in leaves.

Stomata in leaves regulate gas exchange between the plant and its atmosphere. Various environmental stimuli elicit abscisic acid (ABA); ABA leads to phosphoactivation of slow anion channel 1 (SLAC1); SLAC1 activity reduces turgor pressure in aperture-defining guard cells; and stomatal closure ensues. We used electrophysiology for functional characterizations of Arabidopsis thaliana SLAC1 (AtSLAC1) and cryoelectron microscopy (cryo-EM) for structural analysis of Brachypodium distachyon SLAC1 (BdSLAC1), at 2.97-Å resolution. We identified 14 phosphorylation sites in AtSLAC1 and showed nearly 330-fold channel-activity enhancement with 4 to 6 of these phosphorylated. Seven SLAC1-conserved arginines are poised in BdSLAC1 for regulatory interaction with the N-terminal extension. This BdSLAC1 structure has its pores closed, in a basal state, spring loaded by phenylalanyl residues in high-energy conformations. SLAC1 phosphorylation fine-tunes an equilibrium between basal and activated SLAC1 trimers, thereby controlling the degree of stomatal opening.