Biochemical characterization of a multiple prenyltransferase from Tolypocladium inflatum.

Prenylation plays a pivotal role in the diversification and biological activities of natural products. This study presents the functional characterization of TolF, a multiple prenyltransferase from Tolypocladium inflatum. The heterologous expression of tolF in Aspergillus oryzae, coupled with feeding the transformed strain with paxilline, resulted in the production of 20- and 22-prenylpaxilline. Additionally, TolF demonstrated the ability to prenylated the reduced form of paxilline, ß-paxitriol. A related prenyltransferase TerF from Chaunopycnis alba, exhibited similar substrate tolerance and regioselectivity. In vitro enzyme assays using purified recombinant enzymes TolF and TerF confirmed their capacity to catalyze prenylation of paxilline, ß-paxitriol, and terpendole I. Based on previous reports, terpendole I should be considered a native substrate. This work not only enhances our understanding of the molecular basis and product diversity of prenylation reactions in indole diterpene biosynthesis, but also provides insights into the potential of fungal indole diterpene prenyltransferase to alter their position specificities for prenylation. This could be applicable for the synthesis of industrially useful compounds, including bioactive compounds, thereby opening up new avenues for the development of novel biosynthetic strategies and pharmaceuticals. KEY POINTS: • The study characterizes TolF as a multiple prenyltransferase from Tolypocladium inflatum. • TerF from Chaunopycnis alba shows similar substrate tolerance and regioselectivity compared to TolF. • The research offers insights into the potential applications of fungal indole diterpene prenyltransferases.

Pimpinellin ameliorates macrophage inflammation by promoting RNF146-mediated PARP1 ubiquitination.

Macrophage inflammation plays a central role during the development and progression of sepsis, while the regulation of macrophages by parthanatos has been recently identified as a novel strategy for anti-inflammatory therapies. This study was designed to investigate the therapeutic potential and mechanism of pimpinellin against LPS-induced sepsis. PARP1 and PAR activation were detected by western blot or immunohistochemistry. Cell death was assessed by flow cytometry and western blot. Cell metabolism was measured with a Seahorse XFe24 extracellular flux analyzer. C57, PARP1 knockout, and PARP1 conditional knock-in mice were used in a model of sepsis caused by LPS to assess the effect of pimpinellin. Here, we found that pimpinellin can specifically inhibit LPS-induced macrophage PARP1 and PAR activation. In vitro studies showed that pimpinellin could inhibit the expression of inflammatory cytokines and signal pathway activation in macrophages by inhibiting overexpression of PARP1. In addition, pimpinellin increased the survival rate of LPS-treated mice, thereby preventing LPS-induced sepsis. Further research confirmed that LPS-induced sepsis in PARP1 overexpressing mice was attenuated by pimpinellin, and PARP1 knockdown abolished the protective effect of pimpinellin against LPS-induced sepsis. Further study found that pimpinellin can promote ubiquitin-mediated degradation of PARP1 through RNF146. This is the first study to demonstrate that pimpinellin inhibits excessive inflammatory responses by promoting the ubiquitin-mediated degradation of PARP1.

Directed Evolution of 4-Hydroxyphenylpyruvate Biosensors Based on a Dual Selection System.

Biosensors based on allosteric transcription factors have been widely used in synthetic biology. In this study, we utilized the Acinetobacter ADP1 transcription factor PobR to develop a biosensor activating the PpobA promoter when bound to its natural ligand, 4-hydroxybenzoic acid (4HB). To screen for PobR mutants responsive to 4-hydroxyphenylpyruvate(HPP), we developed a dual selection system in E. coli. The positive selection of this system was used to enrich PobR mutants that identified the required ligands. The following negative selection eliminated or weakened PobR mutants that still responded to 4HB. Directed evolution of the PobR library resulted in a variant where PobRW177R was 5.1 times more reactive to 4-hydroxyphenylpyruvate than PobRWT. Overall, we developed an efficient dual selection system for directed evolution of biosensors.

Myricanol attenuates sepsis-induced inflammatory responses by nuclear factor erythroid 2-related factor 2 signaling and nuclear factor kappa B/mitogen-activated protein kinase pathway via upregulating Sirtuin 1.

Sepsis, a life-threatening condition characterized by dysregulated immune responses, remains a significant clinical challenge. Myricanol, a natural compound, plays a variety of roles in regulating lipid metabolism, anti-cancer, anti-neurodegeneration, and it could act as an Sirtuin 1 (SIRT1) activator. This study aimed to explore the therapeutic potential and underlying mechanism of myricanol in the lipopolysaccharide (LPS)-induced sepsis model. In vivo studies revealed that myricanol administration significantly improved the survival rate of LPS-treated mice, effectively mitigating LPS-induced inflammatory responses in lung tissue. Furthermore, in vitro studies demonstrated that myricanol treatment inhibited the expression of pro-inflammatory cytokines, attenuated signal pathway activation, and reduced oxidative stress in macrophages. In addition, we demonstrated that myricanol selectively enhances SIRT1 activation in LPS-stimulated macrophages, and all of the protective effect of myricanol were reversed through SIRT1 silencing. Remarkably, the beneficial effects of myricanol against LPS-induced sepsis were abolished in SIRT1 myeloid-specific knockout mice, underpinning the critical role of SIRT1 in mediating myricanol's therapeutic efficacy. In summary, this study provides significant evidence that myricanol acts as a potent SIRT1 activator, targeting inflammatory signal pathways and oxidative stress to suppress excessive inflammatory responses. Our findings highlight the potential of myricanol as a novel therapeutic agent for the treatment of LPS-induced sepsis.

Whole-cell FRET monitoring of transcription factor activities enables functional annotation of signal transduction systems in living bacteria.

Bacteria adapt to their constantly changing environments largely by transcriptional regulation through the activities of various transcription factors (TFs). However, techniques that monitor TF-promoter interactions in situ in living bacteria are lacking. Herein, we developed a whole-cell TF-promoter binding assay based on the intermolecular FRET between an unnatural amino acid, l-(7-hydroxycoumarin-4-yl) ethylglycine, which labels TFs with bright fluorescence through genetic encoding (donor fluorophore) and the live cell nucleic acid stain SYTO 9 (acceptor fluorophore). We show that this new FRET pair monitors the intricate TF-promoter interactions elicited by various types of signal transduction systems, including one-component (CueR) and two-component systems (BasSR and PhoPQ), in bacteria with high specificity and sensitivity. We demonstrate that robust CouA incorporation and FRET occurrence is achieved in all these regulatory systems based on either the crystal structures of TFs or their simulated structures, if 3D structures of the TFs were unavailable. Furthermore, using CueR and PhoPQ systems as models, we demonstrate that the whole-cell FRET assay is applicable for the identification and validation of complex regulatory circuit and novel modulators of regulatory systems of interest. Finally, we show that the FRET system is applicable for single-cell analysis and monitoring TF activities in Escherichia coli colonizing a Caenorhabditis elegans host. In conclusion, we established a tractable and sensitive TF-promoter binding assay, which not only complements currently available approaches for DNA-protein interactions but also provides novel opportunities for functional annotation of bacterial signal transduction systems and studies of the bacteria-host interface.

High-efficient production of mushroom polyketide compounds in a platform host Aspergillus oryzae.

BACKGROUND: Orsellinic acid (2,4-dihydroxy-6-methylbenzoic acid, OA) and its structural analog o-Orsellinaldehyde, have become widely used intermediates in clinical drugs synthesis. Although the research on the biosynthesis of such compounds has made significant progress, due to the lack of suitable hosts, there is still far from the industrial production of such compounds based on synthetic biology. RESULTS: With the help of genome mining, we found a polyketide synthase (PKS, HerA) in the genome of the Hericium erinaceus, which shares 60% amino acid sequence homology with ArmB from Armillaria mellea, an identified PKS capable of synthesizing OA. To characterize the function of HerA, we cloned herA and heterologously expressed it in Aspergillus oryzae, and successfully detected the production of OA. Subsequently, the introduction of an incomplete PKS (Pks5) from Ustilago maydis containing only three domains (AMP-ACP-R), which was into herA-containing A. oryzae, the resulted in the production of o-Orsellinaldehyde. Considering the economic value of OA and o-Orsellinaldehyde, we then optimized the yield of these compounds in A. oryzae. The screening showed that when maltose was used as carbon source, the yields of OA and o-Orsellinaldehyde were 57.68 mg/L and 15.71 mg/L respectively, while the yields were 340.41 mg/Kg and 84.79 mg/Kg respectively in rice medium for 10 days. CONCLUSIONS: Herein, we successfully expressed the genes of basidiomycetes using A. oryzae heterologous host. As a fungus of ascomycetes, which not only correctly splices genes of basidiomycetes containing multiple introns, but also efficiently produces their metabolites. This study highlights that A. oryzae is an excellent host for the heterologous production of fungal natural products, and has the potential to become an efficient chassis for the production of basidiomycete secondary metabolites in synthetic biology.

A review of synthetic biology tools in Yarrowia lipolytica.

Yarrowia lipolytica is a non-conventional oleaginous yeast with great potential for industrial production. Y. lipolytica has a high propensity for flux through tricarboxylic acid cycle intermediates. Therefore, this host is currently being developed as a workhorse, and is rapidly emerging in biotechnology fields, especially for industrial chemical production, whole-cell bioconversion, and the treatment and recycling of industrial waste. In recent studies, Y. lipolytica has been rewritten and introduced with non-native metabolites of certain compounds of interest owing to the advancement in synthetic biology tools. In this review, we collate recent progress to present a detailed and insightful summary of the major developments in synthetic biology tools and techniques for Y. lipolytica, including promoters, terminators, selection markers, autonomously replicating sequences, DNA assembly techniques, genome editing techniques, and subcellular organelle engineering. This comprehensive overview would be a useful resource for future genetic engineering studies to improve the yield of desired metabolic products in Y. lipolytica.

Genome sequencing of Inonotus obliquus reveals insights into candidate genes involved in secondary metabolite biosynthesis.

BACKGROUND: Inonotus obliquus is an important edible and medicinal mushroom that was shown to have many pharmacological activities in preclinical trials, including anti-inflammatory, antitumor, immunomodulatory, and antioxidant effects. However, the biosynthesis of these pharmacological components has rarely been reported. The lack of genomic information has hindered further molecular characterization of this mushroom. RESULTS: In this study, we report the genome of I. obliquus using a combined high-throughput Illumina NovaSeq with Oxford Nanopore PromethION sequencing platform. The de novo assembled 38.18 Mb I. obliquus genome was determined to harbor 12,525 predicted protein-coding genes, with 81.83% of them having detectable sequence similarities to others available in public databases. Phylogenetic analysis revealed the close evolutionary relationship of I. obliquus with Fomitiporia mediterranea and Sanghuangporus baumii in the Hymenochaetales clade. According to the distribution of reproduction-related genes, we predict that this mushroom possesses a tetrapolar heterothallic reproductive system. The I. obliquus genome was found to encode a repertoire of enzymes involved in carbohydrate metabolism, along with 135 cytochrome P450 proteins. The genome annotation revealed genes encoding key enzymes responsible for secondary metabolite biosynthesis, such as polysaccharides, polyketides, and terpenoids. Among them, we found four polyketide synthases and 20 sesquiterpenoid synthases belonging to four more types of cyclization mechanism, as well as 13 putative biosynthesis gene clusters involved in terpenoid synthesis in I. obliquus. CONCLUSIONS: To the best of our knowledge, this is the first reported genome of I. obliquus; we discussed its genome characteristics and functional annotations in detail and predicted secondary metabolic biosynthesis-related genes, which provides genomic information for future studies on its associated molecular mechanism.

Efficient production of a cyclic dipeptide (cyclo-TA) using heterologous expression system of filamentous fungus Aspergillus oryzae.

BACKGROUND: Cyclic dipeptides are an important class of natural products owing to their structural diversity and biological activities. In fungi, the cyclo-ring system is formed through the condensation of two α-amino acids via non-ribosomal peptide synthetase (NRPS). However, there are few investigations on the functional identification of this enzyme. Additionally, information on how to increase the production of cyclic dipeptide molecules is relatively scarce. RESULTS: We isolated the Eurotium cristatum NWAFU-1 fungus from Jing-Wei Fu brick tea, whose fermentation metabolites contain echinulin-related cyclic dipeptide molecules. We cloned the cirC gene, encoding an NRPS, from E. Cristatum NWAFU-1 and transferred it into the heterologous host Aspergillus oryzae. This transformant produced a novel metabolite possessing an L-tryptophan-L-alanine cyclic dipeptide backbone (Cyclo-TA). Based on the results of heterologous expression and microsomal catalysis, CriC is the first NRPS characterized in fungi that catalyzes the formation of a cyclic dipeptide from L-tryptophan and L-alanine. After substrate feeding, the final yield reached 34 mg/L. In this study, we have characterized a novel NRPS and developed a new method for cyclic dipeptide production. CONCLUSIONS: In this study we successfully expressed the E. Cristatum NWAFU-1 criC gene in A. oryzae to efficiently produce cyclic dipeptide compounds. Our findings indicate that the A. oryzae heterologous expression system constitutes an efficient method for the biosynthesis of fungal Cyclic dipeptides.

Trapping integrated molecular devices via local transport circulation.

Interactions between quantum systems and their environments may always result in inevitable decoherence. Isolation of the quantum system from the undesired environmental noise is a great challenge for ideal quantum information processing. Herein, based on a parallelly shaped control-target molecular nanomagnet structure, we report a novel strategy which decouples the target molecular device from its surrounding conduction baths. By tuning the level differences between the control and target orbitals through external gate voltages, one manipulates both, neither or only the target subsystem to contribute to the quantum transport in sequence, corresponding to an "on-off-on" behavior in the linear conductance. In the off window, a local transport circulation develops, preventing the target device from being disturbed by the itinerant electrons. This finding provides a prospective method for confining integrated quantum devices with high intrinsic fidelity, remarkable tunability, and universal suitability.

Establishment and validation of a postoperative predictive model for patients with colorectal mucinous adenocarcinoma.

BACKGROUND: The aim of this study was to develop comprehensive and effective nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) rates in patients with colorectal mucinous adenocarcinoma (CRMA). METHODS: A total of 4711 CRMA patients who underwent radical surgery between 2010 and 2018 from the Surveillance, Epidemiology, and End Results (SEER) database were collected and randomized into development (n=3299) and validation (n=1412) cohorts at a ratio of 7:3 for model development and validation. OS and CSS nomograms were developed using the prognostic factors from the development cohort after multivariable Cox regression analysis. The performance of the nomograms was evaluated using Harrell's concordance index (C-index), calibration diagrams, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA). RESULTS: The study included 4711 patients. Multivariate Cox regression analysis demonstrated that age, tumor size, grade, pT stage, pN stage, M stage, carcinoembryonic antigen, perineural invasion, tumor deposits, regional nodes examined, and chemotherapy were correlated with OS and CSS. Marital status was independently related to OS. In the development and validation cohorts, the C-index of OS was 0.766 and 0.744, respectively, and the C-index of CSS was 0.826 and 0.809, respectively. Calibration curves and ROC curves showed predictive accuracy. DCA showed that the nomograms had excellent potency over the 8th edition of the TNM staging system with higher clinical net benefits. Significant differences in OS and CSS were observed among low-, medium-, and high-risk groups. CONCLUSIONS: Nomograms were developed for the first time to predict personalized 1-, 3-, and 5-year OS and CSS in CRMA postoperative patients. External and internal validation confirmed the excellent discrimination and calibration ability of the nomograms. The nomograms can help clinicians design personalized treatment strategies and assist with clinical decisions.

Directed evolution of the PobR allosteric transcription factor to generate a biosensor for 4-hydroxymandelic acid.

Hydroxy-mandelic acid (HMA) is widely applied in pharmaceuticals, food and cosmetics. In this study, we aimed to develop an allosteric transcription factors (aTFs) based biosensor for HMA. PobR, an aTF for HMA analog 4-hydroxybenzoic acid, was used to alter its selectivity and create novel aTFs responsive to HMA by directed evolution. We established a PobR mutant library with a capacity of 550,000 mutants using error-prone PCR and Megawhop PCR. Through our screening, two mutants were obtained with responsiveness to HMA. Analysis of each missense mutation indicating residues 122-126 were involved in its PobR ligand specificity. These results showed the effectiveness of directed evolution in switching the ligand specificity of a biosensor and improving HMA production.

Effects of Aurora kinase A on mouse decidualization via Stat3-plk1-cdk1 pathway.

BACKGROUND: Decidualization is essential to the successful pregnancy in mice. The molecular mechanisms and effects of Aurora kinase A (Aurora A) remain poorly understood during pregnancy. This study is the first to investigate the expression and role of Aurora A during mouse decidualization. METHODS: Quantitative real time polymerase chain reaction, western blotting and in situ hybridization were used to determine the expression of Aurora A in mouse uteri. Aurora A activity was inhibited by Aurora A inhibitor to explore the role of Aurora A on decidualization via regulating the Aurora A/Stat3/Plk1/Cdk1 signaling pathway. RESULTS: Aurora A was strongly expressed at implantation sites compared with inter-implantation sites. Furthermore, Aurora A was also significantly increased in oil-induced deciduoma compared with control. Both Aurora A mRNA and protein were significantly increased under in vitro decidualization. Under in vitro decidualization, Prl8a2, a marker of mouse decidualization, was significantly decreased by TC-S 7010, an Aurora A inhibitor. Additionally, Prl8a2 was reduced by Stat3 inhibitor, Plk1 inhibitor and Cdk1 inhibitor, respectively. Moreover, the protein levels of p-Stat3, p-Plk1 and p-Cdk1 were suppressed by TC-S 7010. The protein levels of p-Stat3, p-Plk1 and p-Cdk1 were also suppressed by S3I-201, a Stat3 inhibitor). SBE 13 HCl (Plk1 inhibitor) could reduce the protein levels of p-Plk1 and p-Cdk1. Collectively, Aurora A could regulate Stat3/Plk1/Cdk1 signaling pathway. CONCLUSION: Our study shows that Aurora A is expressed in decidual cells and should be important for mouse decidualization. Aurora A/Stat3/Plk1/Cdk1 signaling pathway may be involved in mouse decidualization.

Kondo effect and RKKY interaction assisted by magnetic anisotropy in a frustrated magnetic molecular device at zero and finite temperature.

Molecular magnetic compounds, which combine the advantages of nanoscale behaviors with the properties of bulk magnetic materials, are particularly attractive in the fields of high-density information storage and quantum computing. Before molecular electronic devices can be fabricated, a crucial task is the measurement and understanding of the transport behaviors. Herein, we consider a magnetic molecular trimer sandwiched between two metal electrodes, and, with the aid of the sophisticated full density matrix numerical renormalization group (FDM-NRG) technique, we study the effect of magnetic anisotropy on the charge transport properties, illustrated by the local density of states (LDOS, which is proportional to the differential conductance), the Kondo effect, and the temperature and inter-monomer hopping robustness. Three kinds of energy peaks are clarified in the LDOS: the Coulomb, the Kondo and the Ruderman-Kittel-Kasuya-Yosida (RKKY) peaks. The local magnetic moment and entropy go through four different regimes as the temperature decreases. The Kondo temperature TK could be described by a generalized Haldane's formula, revealing in detail the process where the local moment is partially screened by the itinerant electrons. A relationship between the width of the Kondo resonant peak WK and TK is built, ensuring the extraction of TK from WK in an efficient way. As the inter-monomer hopping integral varies, the ground state of the trimer changes from a spin quadruplet to a magnetically frustrated phase, then to an orbital spin singlet through two first order quantum phase transitions. In the first two phases, the Kondo peak in the transmission coefficient reaches its unitary limit, while in the orbital spin singlet, it is totally suppressed. We demonstrate that magnetic anisotropy may also induce the Kondo effect, even without Coulomb repulsion, hence it is replaceable in the many-body behaviours at low temperature.

Zinc excess increases cellular demand for iron and decreases tolerance to copper in Escherichia coli.

Transition metals serve as an important class of micronutrients that are indispensable for bacterial physiology but are cytotoxic when they are in excess. Bacteria have developed exquisite homeostatic systems to control the uptake, storage, and efflux of each of biological metals and maintain a thermodynamically balanced metal quota. However, whether the pathways that control the homeostasis of different biological metals cross-talk and render cross-resistance or sensitivity in the host-pathogen interface remains largely unknown. Here, we report that zinc (Zn) excess perturbs iron (Fe) and copper (Cu) homeostasis in Escherichia coli, resulting in increased Fe and decreased Cu levels in the cell. Gene expression analysis revealed that Zn excess transiently up-regulates Fe-uptake genes and down-regulates Fe-storage genes and thereby increases the cellular Fe quota. In vitro and in vivo protein-DNA binding assays revealed that the elevated intracellular Fe poisons the primary Cu detoxification transcription regulator CueR, resulting in dysregulation of its target genes copA and cueO and activation of the secondary Cu detoxification system CusSR-cusCFBA Supplementation with the Fe chelator 2,2'-dipyridyl (DIP) or with the reducing agent GSH abolished the induction of cusCFBA during Zn excess. Consistent with the importance of this metal homeostatic network in cell physiology, combined metal treatment, including simultaneously overloading cells with both Zn (0.25 mm) and Cu (0.25 mm) and sequestering Fe with DIP (50 µm), substantially inhibited E. coli growth. These results advance our understanding of bacterial metallobiology and may inform the development of metal-based antimicrobial regimens to manage infectious diseases.

MicroRNA-363 inhibits angiogenesis, proliferation, invasion, and migration of renal cell carcinoma via inactivation of the Janus tyrosine kinases 2-signal transducers and activators of transcription 3 axis by suppressing growth hormone receptor gene.

Renal cell carcinoma (RCC) is the most common malignancy involving the kidneys and a major cause of cancer mortality. The involvement of microRNA (miRNA) expression in the tumorigenesis and progression of RCC has been previously highlighted. Therefore, we conducted this study to investigate whether microRNA-363 (miR-363) affects the development of RCC via the Janus tyrosine kinases (JAK2)-signal transducers and activators of transcription (STAT) axis by targeting the growth hormone receptor (GHR), by observing the changes that occurred in the RCC and the normal adjacent tissues of patients with RCC. RCC cells were transfected with a series of miR-363 mimic, miR-363 inhibitor, or small interfering RNA against GHR to determine the influence of miR-363 on the expression of GHR and JAK2-STAT3 axis-related genes with the use of reverse transcription quantitative polymerase chain reaction and Western blot analysis. The angiogenesis, viability, invasion, and migration of cells were evaluated by means of in vitro angiogenesis, 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT), wound-healing, and Transwell assays. The results revealed reduced miR-363 expression and elevated GHR expression in RCC. It was also found that miR-363 altered the activation of the JAK2-STAT3 axis through the inhibition of GHR. Cells treated with the miR-363 inhibitor presented with increased capillary vessels, cell viability, invasion, and migration, whereas it was on the contrary in the RCC cells with overexpressed miR-363. These results implicated that the overexpression of miR-363 could specifically bind to GHR to downregulate the expression of GHR, which, in turn, inactivates the JAK2-STAT3 axis, thereby influencing the angiogenesis, cell invasion, and migration abilities in RCC.

Gold nanostars as the saturable absorber for a Q-switched visible solid-state laser.

We demonstrated a passively Q-switched visible Pr:YLF laser using the gold nanostars (GNSs) as the saturable absorber (SA). The nonlinear saturable absorption properties at 639 nm were measured, and the modulation and saturable fluence were calculated to be 3% and 0.3 GW/cm2, respectively. With the GNSs SA, the efficient passively Q-switched lasers were obtained at 639 nm and 721 nm, respectively. The maximum output powers and shortest pulse widths were (256 mW, 168 ns) at 639 nm and (238 mW, 198 ns) for 721 nm. To the best of our knowledge, this is the first time there has been a visible bulk pulse laser using the GNSs as the SA. Our work indicates the GNSs could be excellent and promising optoelectronic devices in the visible domain.

Robot-assisted laparoendoscopic single-site surgery for the simultaneous management of multiple urinary tract calculi: a case report and experience sharing.

BACKGROUND: Urolithiasis is a clinically common benign disease in urology. Surgical treatments that are widely used in urolithiasis are percutaneous nephrolithotomy, rigid/flexible ureteroscopy, laparoscopic surgery, and endoscopic combined intrarenal surgery. The da Vinci surgical system is rarely used in the treatment of urolithiasis. In the current study, we report a case of multiple urinary tract calculi treated by robot-assisted laparoendoscopic single-site (RA-LESS) surgery. CASE PRESENTATION: A 49-year-old male patient was admitted to our hospital and diagnosed with multiple urinary tract calculi. He previously underwent right ureterolithotomy, laparoscopic cholecystectomy, and extracorporeal shockwave lithotripsy. Computed tomography (CT) scan and three-dimensional reconstruction CT image showed that multiple calculi were located in the right kidney, right upper ureter, and bladder. The preoperative glomerular filtration rate (GFR) were 17.81 ml/min (right kidney) and 53.11 ml/min (left kidney). We utilized the da Vinci system docking with a single-site port to perform pyelolithotomy, ureterolithotomy, and cystolithotomy, simultaneously. The operative time was 135 min and estimated blood loss was 30 ml. The postoperative hospital stay was 5 days. Three months after surgery, the serum creatinine and urea nitrogen levels dropped to a normal range, and no residual fragments were found in the CT scan. The postoperative GFR were 26.33 ml/min (right kidney) and 55.25 ml/min (left kidney). CONCLUSIONS: RA-LESS surgery is a safe and effective surgical procedure in the treatment of multiple urinary tract calculi; however, further investigation is needed to validate its long-term therapeutic effect.

Effect of Cu(II) on adsorption of tetracycline by natural zeolite: performance and mechanism.

The purpose of this study was to investigate the effect of Cu(II) on the adsorption performance and mechanism of tetracycline (TC) adsorption by natural zeolite (NZ) in aqueous solution. Low levels of Cu(II) (<0.01 mmol/L) enhanced the extent of TC adsorption from ∼0.4 mg/g (in the absence of Cu(II)) to ∼0.5 mg/g (with 0.01 mmol/L Cu(II)), resulting in 99% removal of the total TC content. The TC adsorption gradually decreased with increase in the initial pH, but the coexistence of Cu(II) lowered the extent of decrease. The adsorption process was better simulated by the pseudo-second-order kinetics model, but the isotherm model that was more fitting changed from the Langmuir to the Freundlich model as Cu(II) increased, indicating the coexistence of Cu(II) and TC altered the adsorption mechanisms. However, the residual TC in solution increased from 0 to ∼6 mg/L as the concentration of Cu(II) increased from 0 to 1 mmol/L, suggesting a competition between TC and Cu(II) for the adsorption sites in NZ. Fourier transform infrared spectroscopy analysis showed that the functional groups on the surface of NZ changed after the adsorption of TC, suggesting that complex reactions had occurred on the surface of the adsorbent.

Hydrogen bonding and dominant conformations of hydrated sugar analogue complexes using tetrahydrofurfuryl alcohol as the model sugar molecule.

Water molecules, which serve as both hydrogen bond donors and acceptors, have been found to influence the conformational landscape of gas-phase phenyl-ß-d-glucopyranoside. Herein, tetrahydrofurfuryl alcohol (THFA), a sugar-like molecule without chromophores (e.g. phenyl-substitution), was used as the model sugar molecule for exploring the behaviour of water molecules on the conformational landscape of a pentose sugar such as deoxyribose. We used mass selected infrared-vacuum ultraviolet (IR-VUV) (118 nm) spectroscopy to investigate the hydrated neutral THFA and its complex cation in a supersonic jet. High level density functional theory (DFT) calculations were performed to ascertain the experimental results. The results revealed that the water molecule tends to insert into the twisted conformer at a position where two stronger intermolecular hydrogen bonds were formed by breaking the weak intramolecular interactions. We found that the twisted conformer of the hydrated neutral THFA complex is more stable than the envelope conformation, while the latter is more stable for the THFA molecule. However, the conformational landscape of the hydrated THFA complex cation did not significantly change on microsolvation with water molecules. These results indicated that the dominant structural landscape of the hydrated cationic complex is the twisted configuration with a trans-hydroxymethyl group. This finding provides valuable insight into the microsolvation of gas-phase sugar molecules.