Induction of Sestrin2 by pterostilbene suppresses ethanol-triggered hepatocyte senescence by degrading CCN1 via p62-dependent selective autophagy.

Hepatocyte senescence is a key event participating in the progression of alcoholic liver disease. Autophagy is a critical biological process that controls cell fates by affecting cell behaviors like senescence. Pterostilbene is a natural compound with hepatoprotective potential; however, its implication for alcoholic liver disease was not understood. This study was aimed to investigate the therapeutic effect of pterostilbene on alcoholic liver disease and elucidate the potential mechanism. Our results showed that pterostilbene alleviated ethanol-triggered hepatocyte damage and senescence. Intriguingly, pterostilbene decreased the protein abundance of cellular communication network factor 1 (CCN1) in ethanol-exposed hepatocytes, which was essential for pterostilbene to execute its anti-senescent function. In vivo studies verified the anti-senescent effect of pterostilbene on hepatocytes of alcohol-intoxicated mice. Pterostilbene also relieved senescence-associated secretory phenotype (SASP), redox imbalance, and steatosis by suppressing hepatic CCN1 expression. Mechanistically, pterostilbene-forced CCN1 reduction was dependent on posttranscriptional regulation via autophagy machinery but not transcriptional regulation. To be specific, pterostilbene restored autophagic flux in damaged hepatocytes and activated p62-mediated selective autophagy to recognize and lead CCN1 to autolysosomes for degradation. The protein abundance of Sestrin2 (SESN2), a core upstream modulator of autophagy pathway, was decreased in ethanol-administrated hepatocytes but rescued by co-treatment with pterostilbene. Induction of SESN2 protein by pterostilbene rescued ethanol-triggered autophagic dysfunction in hepatocytes, which then reduced senescence-associated markers, postponed hepatocyte senescence, and relieved alcohol-caused liver injury and inflammation. In conclusion, this work discovered a novel compound pterostilbene with therapeutic implications for alcoholic liver disease and uncover its underlying mechanism.

Synthesis of 1-substituted phenazines as novel antichlamydial agents.

A novel series of 1-substituted phenazines 4a-4l were designed and synthesized via Palladium-catalyzed reactions from 1-phenazine trifluoromethanesulfonate. These phenazines showed antichlamydial activity with IC50 values from 1 to 10 µM. Among them, compounds 4c and 4i exhibited the best antichlamydial activity with IC50 values from 2.06 to 2.74 µM without apparent cytotoxicity to host cells.

Procyanidin B2 and rutin in Ginkgo biloba extracts protect human retinal pigment epithelial (RPE) cells from oxidative stress by modulating Nrf2 and Erk1/2 signalling.

Oxidative stress plays an important role in the pathogenesis of human retinal diseases. Ginkgo biloba products are widely consumed herbal supplements that contain ingredients with anti-oxidant potentials. However, the active agents in ginkgo biloba extracts (GBE) are unclear. This study assessed the anti-oxidant effects of 19 natural compounds isolated from GBE to provide a rational basis for their use in preventing retinal diseases. The compounds were tested in retinal pigment epithelial (RPE) cells subjected to tert-butyl hydroperoxide (t-BHP)-induced oxidative stress. Cell viability and intracellular reactive oxygen species (ROS) were assessed and flow cytometry was used to delineate the cell death profile. The expression of nuclear factor erythroid 2-related factor-2 (Nrf2) was activated in RPE cells by t-BHP accompanied with an activation of Erk1/2 signaling. GBE-derived rutin and procyanidin B2 ameliorated t-BHP-induced cell death and promoted cell viability by suppressing intracellular ROS generation. These agents also enhanced Nrf2 expression with activating Erk1/2 signaling in RPE cells. In contrast, the other compounds tested were minimally active and did not prevent the loss of cell viability elicited by t-BHP. The present findings suggest that rutin and procyanidin B2 may have potential therapeutic values in the prevention of retinal diseases induced by oxidative damage.

Volatile organic compounds from a mixed fleet with numerous E10-fuelled vehicles in a tunnel study in China: Emission characteristics, ozone formation and secondary organic aerosol formation.

The Chinese government has developed an ambitious project to promote the application of ethanol gasoline (E10) on a national scale since 2017. Given the difference in fuel properties between E10 and traditional gasoline, it is necessary to evaluate the volatile organic compound (VOC) emissions from E10-fuelled vehicles. In this study, a two-week sampling campaign was conducted in an urban tunnel, in which E10-fuelled vehicles were dominant, to evaluate the characteristics of VOC emissions from the mixed fleet. In total, 105 VOC species were identified, and the ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) were estimated. The results showed that for vehicular VOC concentrations in the tunnel, alkanes, oxygenated VOCs (OVOCs) and alkenes were the most abundant VOC groups, with the average proportion being more than 80% of the total VOCs. The fleet-average VOC emission factor (EF) was 14.8 mg/km/veh, which was much lower than that from traditional gasoline-fuelled vehicle fleets, and alkanes, OVOCs, alkenes and aromatics were the major VOC groups. Because of the large number of E10-fuelled vehicles in the mixed fleet, a high proportion of OVOCs among the vehicular VOC emissions was observed. Ethane, acrolein, ethanol, ethylene and toluene were the top five VOC species with the largest EF in VOC emissions from the fleet. Alkenes were the main contributors with an average contribution of 43.9% of the total OFP, whereas aromatics dominated the total SOAFP by 95.8% on average. These results may provide a reference for the extensive application of ethanol gasoline and the development of vehicular emission models.

A selective and sensitive turn-on chemosensor for detection of Fe3+ in aqueous solution and its cell imaging in dorsal root ganglia neurons and MKN-45 cells.

A new turn-on fluorescent chemosensor (RBTM) for Fe3+ was designed based on Rhodamine B and a thiocarbonylimidazole moiety. The spectroscopic probe used for characterization of the synthesized system showed 300-fold fluorescence enhancement for the detection of Fe3+ with a 1:1 stoichiometry in EtOH/H2O solution (2:1, v/v, HEPES buffer, 1 mM, pH 7.30). Upon addition of Fe3+ in aqueous ethanol, the probe displayed a significant fluorescence enhancement and a distinct color change (colorless to pink) that can be detected by the naked eye. The binding constant between the probe and Fe3+ was determined to be 1.16 × 104 M-1 and the corresponding detection limit was calculated to be 0.256 µM. In addition, the energy gaps between the HOMO and LUMO in RBTM and RBTM-Fe3+ were calculated using DFT calculations to be 92.93 kcal/mol and 37.49 kcal/mol, respectively. The results indicate that binding of Fe3+ to RBTM lowered the HOMO-LUMO energy gap of the complex and stabilized the system. Fluorescence imaging experiments demonstrated that RBTM can be used as a fluorescent probe to detect Fe3+ in MKN-45 cells and dorsal root ganglia, thus revealing that RBTM could be used for biological applications.

Dual-binding pyridine and rhodamine B conjugate derivatives as fluorescent chemosensors for ferric ions in aqueous media and living cells.

Two new pyridine-type rhodamine B chemosensors (RBPO and RBPF) used to detect Fe3+ have been designed and synthesized, and the sensing behavior towards various metal ions was evaluated via UV-vis and fluorescence spectroscopic techniques. Both RBPO and RBPF not only have good spectral responses to Fe3+ in an EtOH/H2O solution (3 : 1, v/v, HEPES, 0.5 mM, pH = 7.33) with low detection limits and high binding constants, but also suffer from less interference from common metal cations. The two chemosensors are further proven to be practical in sensitively monitoring trace Fe3+ in real water specimens. Intracellular imaging applications demonstrated that RBPO and RBPF can be used as two fluorescent chemosensors for the detection of Fe3+ in living human breast adenocarcinoma (MCF-7) cells.

Role for GrgA in Regulation of σ28-Dependent Transcription in the Obligate Intracellular Bacterial Pathogen Chlamydia trachomatis.

The obligate intracellular bacterial pathogen Chlamydia trachomatis has a unique developmental cycle consisting of two contrasting cellular forms. Whereas the primary Chlamydia sigma factor, σ66, is involved in the expression of the majority of chlamydial genes throughout the developmental cycle, expression of several late genes requires the alternative sigma factor, σ28 In prior work, we identified GrgA as a Chlamydia-specific transcription factor that activates σ66-dependent transcription by binding DNA and interacting with a nonconserved region (NCR) of σ66 Here, we extend these findings by showing GrgA can also activate σ28-dependent transcription through direct interaction with σ28 We measure the binding affinity of GrgA for both σ66 and σ28, and we identify regions of GrgA important for σ28-dependent transcription. Similar to results obtained with σ66, we find that GrgA's interaction with σ28 involves an NCR located upstream of conserved region 2 of σ28 Our findings suggest that GrgA is an important regulator of both σ66- and σ28-dependent transcription in C. trachomatis and further highlight NCRs of bacterial RNA polymerase as targets for regulatory factors unique to particular organisms.IMPORTANCEChlamydia trachomatis is the number one sexually transmitted bacterial pathogen worldwide. A substantial proportion of C. trachomatis-infected women develop infertility, pelvic inflammatory syndrome, and other serious complications. C. trachomatis is also a leading infectious cause of blindness in underdeveloped countries. The pathogen has a unique developmental cycle that is transcriptionally regulated. The discovery of an expanded role for the Chlamydia-specific transcription factor GrgA helps us understand the progression of the chlamydial developmental cycle.

Pyocyanin Inhibits Chlamydia Infection by Disabling Infectivity of the Elementary Body and Disrupting Intracellular Growth.

The obligate intracellular bacterium Chlamydia is a widespread human pathogen that causes serious problems, including (but not limited to) infertility and blindness. Our search for novel antichlamydial metabolites from marine-derived microorganisms led to the isolation of pyocyanin, a small compound from Pseudomonas aeruginosa Pyocyanin is an effective antichlamydial for all three Chlamydia spp. tested. It has a 50% inhibitory concentration (IC50) of 0.019 to 0.028 µM, which is comparable to the IC50 of tetracycline. At concentrations as low as 0.0039 µM, pyocyanin disables infectivity of the chlamydial elementary body (EB). At 0.5 µM or higher concentrations, the continuous presence of pyocyanin also inhibits chlamydial growth in the inclusion during later stages of the developmental cycle. Oxidative stress, a major known antimicrobial mechanism of pyocyanin, appears to be responsible only for the inhibition of bacterial growth and not for the disinfection of EBs. Pyocyanin is well-tolerated by probiotic vaginal Lactobacillus spp. Our findings suggest that pyocyanin is of therapeutic value for chlamydial infections and can serve as a valuable chemical probe for studying chlamydial biology.

Distinct Roles For ROCK1 and ROCK2 in the Regulation of Oxldl-Mediated Endothelial Dysfunction.

BACKGROUND/AIMS: This study used Rho-associated protein kinase (ROCK) isoform-selective suppression or a ROCK inhibitor to analyze the roles of ROCK1 and ROCK2 in regulating endothelial dysfunction triggered by oxidized low-density lipoprotein (oxLDL). METHODS: ROCK1 or ROCK2 expression in human umbilical vein endothelial cells (HUVECs) was suppressed by small interfering RNA (siRNA). HUVECs were pretreated with 30 µM Y27632 (pan ROCK inhibitor) for 30 min before exposure to 200 µg/mL oxLDL for an additional 24 h. Cell viability was determined by the MTT assay, and cell apoptosis was evaluated by the TUNEL assay. Protein expression and phosphorylation were assessed by Western blot analysis. The morphology of total and phosphorylated vimentin (p-vimentin) and the co-localization of vimentin with vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) were detected by the immunofluorescence assay. The adhesion of promonocytic U937 cells to HUVECs was observed by light microscopy. RESULTS: ROCK2 suppression or Y27632 treatment, rather than ROCK1 deletion, effectively reduced endothelial cell apoptosis and preserved cell survival. ROCK2 suppression exhibited improved vimentin and p-vimentin cytoskeleton stability and decreased vimentin cleavage by attenuating caspase-3 activity. In addition, increased p-vimentin expression induced by oxLDL was significantly inhibited by ROCK2 deletion or Y27632 treatment. In contrast, ROCK1 suppression showed no obvious effects on the vimentin cytoskeleton, but significantly regulated the expression of adhesion molecules. Endothelial ICAM-1 or VCAM-1 expression induced by oxLDL was obviously inhibited by ROCK1 suppression or Y27632 treatment. Moreover, the expression of ICAM-1 induced by oxLDL could also be reduced by ROCK2 suppression. Furthermore, ROCK2 deficiency or Y27632 treatment inhibited the redistribution of adhesion molecules and their co-localization with vimentin caused by oxLDL. These effects resulted in the significant inhibition of monocyte-endothelial adhesion induced by oxLDL. CONCLUSION: The results of this study support the novel concept that ROCK1 is involved in oxLDL-induced cell adhesion by regulating adhesion molecule expression, whereas ROCK2 is required for both endothelial apoptosis and adhesion by regulating both the vimentin cytoskeleton and adhesion molecules. Consequently, ROCK1 and ROCK2 have distinct roles in the regulation of oxLDL-mediated endothelial dysfunction.

Synthesis and evaluation of a novel 'off-on' chemical sensor based on rhodamine B and the 2,5-pyrrolidinedione moiety for selective discrimination of glutathione and its bioimaging in living cells.

A new "turn-on" fluorescent probe, RDMBM, based on the rhodamine B dye and the 2,5-pyrrolidinedione moiety was synthesized and characterized. Its sensing behavior toward various amino acids was evaluated via UV-vis and fluorescence spectroscopic techniques. The observed spectral changes showed that RDMBM displays high selectivity and sensitivity toward GSH in MeOH/H2O (1:2, v/v, pH 7.40, Tris-HCl buffer, 1 mM) solution and that it undergoes 1:1 covalent binding with GSH. More importantly, the hydrogenation and ring-opening of the nitrogen atom in the spirane structure of rhodamine B derivatives were tightly bound to the induction effects of different groups. Furthermore, fluorescence imaging applications demonstrated that RDMBM can be successfully used for the detection of GSH in human breast cancer cells MCF-7.

In vitro Antichlamydial Activity of 1,2,3,5-Tetrasubstituted Pyrrole Derivatives.

BACKGROUND: Chlamydia is a group of bacterial pathogens distributed worldwide that can lead to serious reproductive and other health problems. The rise of antibiotic-resistant pathogens promotes the development of novel antichlamydial agents. The aim of this study is to assess in vitro antichlamydial activity of our previously synthesized 1,2,3,5- tetrasubstituted pyrroles. METHODS: The derivatives were screened for their antichlamydial activity against three Chlamydia strains by calculating IC50 values using concentration-response inhibition data between 1 and 32 µM. The action of the compounds on Chlamydia elementary body (EB) infectivity and the impact of the chemicals' administration time on their antichlamydial effect were evaluated to reveal the inhibitory mechanism. RESULTS: Some of the compounds moderately inhibited the Chlamydia strains. Compound 10 exhibited the strongest inhibitory activity, with IC50 values from 4.34 to 5.83 µM. These pyrrole derivatives inhibited Chlamydia infection by reducing EB infectivity during the early stage and disturbing Chlamydia growth by targeting the early-to-middle stage prior to 12 h of the chlamydial life cycle. CONCLUSION: Our findings highlight the potential of 1,2,3,5-tetrasubstituted pyrrole derivatives as promising lead molecules for the development of antichlamydial agents.

Dihydromyricetin Attenuates Myocardial Hypertrophy Induced by Transverse Aortic Constriction via Oxidative Stress Inhibition and SIRT3 Pathway Enhancement.

Dihydromyricetin (DMY), one of the flavonoids in vine tea, exerts several pharmacological actions. However, it is not clear whether DMY has a protective effect on pressure overload-induced myocardial hypertrophy. In the present study, male C57BL/6 mice aging 8⁻10 weeks were subjected to transverse aortic constriction (TAC) surgery after 2 weeks of DMY (250 mg/kg/day) intragastric administration. DMY was given for another 2 weeks after surgery. Blood pressure, myocardial structure, cardiomyocyte cross-sectional area, cardiac function, and cardiac index were observed. The level of oxidative stress in the myocardium was assessed with dihydroethidium staining. Our results showed that DMY had no significant effect on the blood pressure. DMY decreased inter ventricular septum and left ventricular posterior wall thickness, relative wall thickness, cardiomyocyte cross-sectional areas, as well as cardiac index after TAC. DMY pretreatment also significantly reduced arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP) mRNA and protein expressions, decreased reactive oxygen species production and malondialdehyde (MDA) level, while increased total antioxidant capacity (T-AOC), activity of superoxide dismutase (SOD), expression of sirtuin 3 (SIRT3), forkhead-box-protein 3a (FOXO3a) and SOD2, and SIRT3 activity in the myocardium of mice after TAC. Taken together, DMY ameliorated TAC induced myocardial hypertrophy in mice related to oxidative stress inhibition and SIRT3 pathway enhancement.

Antichlamydial Dimeric Indole Derivatives from Marine Actinomycete Rubrobacter radiotolerans.

Chlamydiae are widely distributed pathogens of human populations, which can lead to serious reproductive and other health problems. In our search for novel antichlamydial metabolites from marine derived-microorganisms, one new (1) and two known (2, 3) dimeric indole derivatives were isolated from the sponge-derived actinomycete Rubrobacter radiotolerans. The chemical structures of these metabolites were elucidated by NMR spectroscopic data as well as CD calculations. All three metabolites suppressed chlamydial growth in a concentration-dependent manner. Among them, compound 1 exhibited the most effective antichlamydial activity with IC50 values of 46.6 ~ 96.4 µM in the production of infectious progeny. Compounds appeared to target the mid-stage of the chlamydial developmental cycle by interfering with reticular body replication, but not directly inactivating the infectious elementary body.

GM1 ganglioside reverses the cognitive deficits induced by MK801 in mice.

Cognitive deficits are core symptoms of schizophrenia, but effective treatments are still lacking. Previous studies have reported that the brain-derived neurotrophic factor (BDNF) signaling is closely involved in learning and memory. Monosialotetrahexosylganglioside (GM1) is a ganglioside with wide-ranging pharmacologic effects that enhances the BDNF signaling cascade. This study aimed to assess the effects of GM1 on schizophrenia-related cognitive impairments. A brief disruption of N-methyl-D-aspartate receptors with MK801 was used to generate the animal model for cognitive deficits in schizophrenia. It was found that MK801-treated mice showed significant deficits in memory ability compared with control mice in different behavior tests, and this was accompanied by decreased hippocampal BDNF signaling pathway. Consecutive administration of GM1 fully restored the MK801-induced cognitive deficits and the impaired BDNF signaling in the hippocampus. Furthermore, a BDNF system inhibitor abolished the effects of GM1 in the MK801 model. Taken together, our results show that GM1 could reverse the MK801-induced cognitive deficits, suggesting a potential usefulness of GM1 in treating the schizophrenia-related cognitive impairments.

Gaseous emissions from compressed natural gas buses in urban road and highway tests in China.

The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas (CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0-10km/hr were increased to 10-20km/hr, the CO2, CO, nitrogen oxide (NOx), and total hydrocarbon (THC) emission factors decreased by (71.6±4.3)%, (65.6±9.5)%, (64.9±9.2)% and (67.8±0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards (Euro IV) did not have lower emission factors than the Chongqing coaches with Euro II emission standards. Both the higher emission factors at 0-10km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO2 and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most (by 83.2%), followed by the THC emission factors, which decreased by 67.1%.

Synthesis and evaluation of a novel Rhodamine B pyrene [2]rotaxane as an intracellular delivery agent for doxorubicin.

A novel Rhodamine B-derivatized host [2]rotaxane, containing a dibenzyl-24-crown-8 (DB24C8) ring as the wheel and a pyrene as another fluorophore blocking group, was designed, synthesized and structurally characterized. A comparison of the (1)H NMR spectra of RhBPy [2]rotaxane with those of and DB24C8, nuclear Overhauser effect spectroscopy (NOESY), mass spectrometry and fluorescence spectroscopy confirmed the interlocked nature of RhBPy [2]rotaxane. The temperature dependence of the rotaxane studied by (1)H NMR spectroscopy further demonstrated that RhBPy [2]rotaxane can be applied as a molecular switch. RhBPy [2]rotaxane has also been demonstrated to be an efficient transport agent for delivering the cancer drug doxorubicin (DOX) into tumor cells. Indeed, DOX delivered by RhBPy [2]rotaxane could effectively inhibit tumor cell growth.

Synthesis and evaluation of a new Rhodamine B and Di(2-picolyl)amine conjugate as a highly sensitive and selective chemosensor for Al3+ and its application in living-cell imaging.

A new Rhodamine B derivative (RBDPA), namely, N(1)-(2-(3',6'-bis(diethylamino)-3-oxospiro[isoindoline-1,9'-xanthen]-2-yl)ethyl)-N(4),N(4)-bis(pyridin-2-ylmethyl)succinamide, was designed, synthesized and structurally characterized to develop a chemosensor. The studies show that RBDPA exhibits high sensitivity and selectivity toward Al(3+) among many other metal cations in an ethanol/H2O (1:1, v/v, pH=7.2, HEPES buffer, 0.1mM) solution. Fluorescence microscopy experiments further demonstrate that RBDPA can be used as a fluorescent probe to detect Al(3+) in living cells.

Chlamydia trachomatis protein GrgA activates transcription by contacting the nonconserved region of σ66.

The bacterial RNA polymerase holoenzyme consists of a catalytic core enzyme in complex with a σ factor that is required for promoter-specific transcription initiation. Primary, or housekeeping, σ factors are responsible for most of the gene expression that occurs during the exponential phase of growth. Primary σ factors share four regions of conserved sequence, regions 1-4, which have been further subdivided. Many primary σ factors also contain a nonconserved region (NCR) located between subregions 1.2 and 2.1, which can vary widely in length. Interactions between the NCR of the primary σ factor of Escherichia coli, σ(70), and the ß' subunit of the E. coli core enzyme have been shown to influence gene expression, suggesting that the NCR of primary σ factors represents a potential target for transcription regulation. Here, we report the identification and characterization of a previously undocumented Chlamydia trachomatis transcription factor, designated GrgA (general regulator of genes A). We demonstrate in vitro that GrgA is a DNA-binding protein that can stimulate transcription from a range of σ(66)-dependent promoters. We further show that GrgA activates transcription by contacting the NCR of the primary σ factor of C. trachomatis, σ(66). Our findings suggest GrgA serves as an important regulator of σ(66)-dependent transcription in C. trachomatis. Furthermore, because GrgA is present only in chlamydiae, our findings highlight how nonconserved regions of the bacterial RNA polymerase can be targets of regulatory factors that are unique to particular organisms.

[The value of transesophageal echocardiography to guide the implantation of 2 pieces of MitraClip during transcatheter mitral valve repair operation].

OBJECTIVE: To investigate the value of transesophageal echocardiography to guide the implantation of 2 pieces of MitraClip during transcatheter mitral valve repair operation. METHODS: From October 2013 to June 2014, 6 transcatheter mitral valve repair operations were performed in our hospital for symptomatic patients with severe functional mitral regurgitation (MR), transesophageal echocardiography was applied to guide the implantation of 2 pieces of MitraClip. Clinical data are retrospectively analyzed to evaluate implantation timing and approach of the 2nd piece of MitraClip, as well as the immediate effect of the interventional therapy. RESULTS: After implantation of 1st piece of MitraClip, transesophageal echocardiography evidenced MR ≥ grade 2 with central regurgitation and immediate mitral average transvalvular pressure gradient < 3 mmHg (1 mmHg = 0.133 kPa) in these 6 patients and 2nd piece of MitraClip was implanted in these patients. After implantation of 2nd piece of MitraClip, it is observed via transesophageal echocardiography that mitral regurgitations were reduced by ≥ 2 grades for all 6 patients. For 3 patients, MR was reduced to grade 1. For the other 3 patients, MR is reduced to grade 2. Among the 3 patients whose MR was reduced to grade 2, 2 operations were stopped because immediate mitral average transvalvular pressure gradient equaled to 3 mmHg, and the rest 1 operation was stopped because MR was too diverse and not able to select proper position to implant the next MitraClip. All 6 operations are completed successfully.There were no myocardial infarction, death or complications requiring mitral valve surgery after the MitraClip procedure. There were also no MitraClip detachment, thrombus embolism, mitral valve apparatus injuries, mitral stenosis, pericardial tamponade post procedure. CONCLUSIONS: Transesophageal echocardiography plays an important role to guide the implantation of 2 pieces of MitraClip in transcatheter mitral valve repair operation. Mitral average transvalvular pressure gradient and initial position of regurgitation after implantation of the previous MitraClip are critical determinants for decision making if the next piece of MitraClip can be implanted or not.

Benzylidene acylhydrazides inhibit chlamydial growth in a type III secretion- and iron chelation-independent manner.

Chlamydiae are widespread Gram-negative pathogens of humans and animals. Salicylidene acylhydrazides, developed as inhibitors of type III secretion system (T3SS) in Yersinia spp., have an inhibitory effect on chlamydial infection. However, these inhibitors also have the capacity to chelate iron, and it is possible that their antichlamydial effects are caused by iron starvation. Therefore, we have explored the modification of salicylidene acylhydrazides with the goal to uncouple the antichlamydial effect from iron starvation. We discovered that benzylidene acylhydrazides, which cannot chelate iron, inhibit chlamydial growth. Biochemical and genetic analyses suggest that the derivative compounds inhibit chlamydiae through a T3SS-independent mechanism. Four single nucleotide polymorphisms were identified in a Chlamydia muridarum variant resistant to benzylidene acylhydrazides, but it may be necessary to segregate the mutations to differentiate their roles in the resistance phenotype. Benzylidene acylhydrazides are well tolerated by host cells and probiotic vaginal Lactobacillus species and are therefore of potential therapeutic value.