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Background: Urolithiasis is a highly prevalent global disease closely associated with metabolic factors; however, the causal relationship between blood metabolites and urolithiasis remains poorly understood. Method: In our study, we employed a bi-directional two-sample Mendelian randomization (MR) analysis to investigate the causal associations between urolithiasis and metabolites. The random-effects inverse-variance weighted (IVW) estimation method was utilized as the primary approach, complemented by several other estimators including MR-Egger, weighted median, colocalization and MR-PRESSO. Furthermore, the study included replication and meta-analysis. Finally, we conducted metabolic pathway analysis to elucidate potential metabolic pathways. Results: After conducting multiple tests for correction, glycerol might contribute to the urolithiasis and dehydroisoandrosterone sulfate (DHEA-S) might inhibit this process. Furthermore, several blood metabolites had shown potential associations with a causal relationship. Among the protective metabolites were lipids (dehydroisoandrosterone sulfate and 1-stearoylglycerol (1-monostearin)), amino acids (isobutyrylcarnitine and 2-aminobutyrate), a keto acid (acetoacetate) and a carbohydrate (mannose). The risk metabolites included lipids (1-palmitoylglycerophosphoethanolamine, glycerol and cortisone), a carbohydrate (erythronate), a peptide (pro-hydroxy-pro) and a fatty acid (eicosenoate). In reverse MR analysis, urolithiasis demonstrated a statistically significant causal relationship with butyrylcarnitine, 3-methyl-2-oxobutyrate, scyllo-inositol, leucylleucine and leucylalanine. However, it was worth noting that none of the blood metabolites exhibited statistical significance after multiple corrections. Additionally, we identified one metabolic pathway associated with urolithiasis. Conclusion: The results we obtained demonstrate the causal relevance between two metabolites and urolithiasis, as well as identify one metabolic pathway potentially associated with its development. Given the high prevalence of urolithiasis, further investigations are encouraged to elucidate the mechanisms of these metabolites and explore novel therapeutic strategies. [ABSTRACT FROM AUTHOR]

Mitochondria are essential organelles because they generate the energy required for cellular functions. Kidney stones, as one of the most common urological diseases, have garnered significant attention. In this study, we first collected peripheral venous blood from patients with kidney stones and used qRT-PCR to detect mitochondrial DNA (mtDNA) copy number as a means of assessing mitochondrial function in these patients. Subsequently, through Western blotting, qPCR, immunofluorescence, immunohistochemistry, and transmission electron microscopy, we examined whether calcium oxalate crystals could cause mitochondrial dysfunction in the kidney in both in vitro and in vivo. We then examined the intersection of the DEGs obtained by transcriptome sequencing of the mouse kidney stone model with mitochondria-related genes, and performed KEGG and GO analyses on the intersecting genes. Finally, we administered the mitochondrial ROS scavenger Mito-Tempo in vivo and observed its effects. Our findings revealed that patients with kidney stones had a reduced mtDNA copy number in their peripheral venous blood compared to the control group, suggesting mitochondrial dysfunction in this population. This conclusion was further validated through in vitro and in vivo experiments. Enrichment analyses revealed that the intersecting genes were closely related to metabolism. We observed that after mitochondrial function was preserved, the deposition of calcium oxalate crystals decreased, and the kidney damage and inflammation caused by them were also alleviated. Our research indicates that kidney stones can cause mitochondrial dysfunction. After clearing mtROS, the damage and inflammation caused by kidney stones are reversed, providing new insights into the prevention and treatment of kidney stones. [ABSTRACT FROM AUTHOR]

Background: Kidney stones account for a high proportion of urological emergencies. The main objective of this paper is to evaluate the predictive ability of five scoring systems for overall stone-free status and postoperative complications after percutaneous nephrolithotomy and retrograde ureteroscopy. Materials and methods: This study retrospectively analysed 312 cases of kidney stone patients between January 2021 and May 2022 at our centre. Multivariate logistic regression as well as ROC curves were applied to determine the ability to evaluate each scale to predict stone-free rates and postoperative complications. Results: 179 patients have undergone PCNL. After multivariate logistic regression, the S.T.O.N.E score and history of ipsilateral renal surgery were predictive of stone-free status, and the predictive power of the S.T.O.N.E score was higher than that of history of ipsilateral renal surgery. Grade 1 complications were considered to be related to Guy's score and grade 2 complications were considered to be related to history of diabetes mellitus. 133 patients have undergone f-URS. After multivariate logistic regression analysis, the modified S-ReSC score, RUSS score, and R.I.R.S score were predictive of stone-free status, with the R.I.R.S score being the strongest predictor. Evidence of grade 2 complications was considered to be related to abnormal renal function. Conclusion: For PCNL, the S.T.O.N.E score had the best efficacy in predicting stone-free status, and the Guy's score had the best efficacy in predicting postoperative complications; for f-URS, the R.I.R.S score had the best efficacy in predicting stone-free status, and no scoring system predicted postoperative complications. [ABSTRACT FROM AUTHOR]

Rhizoma Polygonati (RP) is the dried rhizome of the liliaceous plant. It has anti-inflammatory and anti-apoptosis effects. But its role in kidney stones has not been studied. The purpose of this study was to verify the effect of RP in the treatment of nephrolithiasis through network pharmacological analysis and in vivo experiments. The active compounds and protein targets of RP, as well as the potential targets of the nephrolithiasis were searched from the database. The protein–protein interaction (PPI) network diagram and the drug–compounds–targets–disease network were constructed. The enrichment analysis was performed by Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG). Subsequently, the effect of RP on the prevention and treatment of nephrolithiasis was experimentally validated in vivo. Animal experiments showed that RP ameliorates renal function and reduced crystal deposition in a mouse model. It may act through anti-inflammation and anti-apoptosis. Our study showed that RP could prevent and treat nephrolithiasis by inhibiting apoptosis and inflammation, which provided a new efficacy and clinical application for RP. [ABSTRACT FROM AUTHOR]

Background: Antibiotics biosynthesis is usually regulated by the cluster-situated regulatory gene(s) (CSRG(s)), which directly regulate the genes within the corresponding biosynthetic gene cluster (BGC). Previously, we have demonstrated that LmbU functions as a cluster-situated regulator (CSR) of lincomycin. And it has been found that LmbU regulates twenty non-lmb genes through comparative transcriptomic analysis. However, the regulatory mode of CSRs' targets outside the BGC remains unknown. Results: We screened the targets of LmbU in the whole genome of Streptomyces lincolnensis and found fourteen candidate targets, among which, eight targets can bind to LmbU by electrophoretic mobility shift assays (EMSA). Reporter assays in vivo revealed that LmbU repressed the transcription of SLINC_0469 and SLINC_1037 while activating the transcription of SLINC_8097. In addition, disruptions of SLINC_0469, SLINC_1037, and SLINC_8097 promoted the production of lincomycin, and qRT-PCR showed that SLINC_0469, SLINC_1037, and SLINC_8097 inhibited transcription of the lmb genes, indicating that all the three regulators can negatively regulate lincomycin biosynthesis. Conclusions: LmbU can directly regulate genes outside the lmb cluster, and these genes can affect both lincomycin biosynthesis and the transcription of lmb genes. Our results first erected the cascade regulatory circuit of LmbU and regulators outside lmb cluster, which provides the theoretical basis for the functional research of LmbU family proteins. [ABSTRACT FROM AUTHOR]

Cascaded H-bridge power electronic transformers (CHB-PET) play a pivotal role in distribution grids and their efficient operation. The input series and output parallel (ISOP) configurations result in a huge number of power switching devices, high-frequency transformers (HFT), and capacitors in high-voltage, high-capacity CHB-PET, leading to the need for high hardware costs and huge-sized CHB-PET, which further poses a significant challenge to the engineering feasibility and marketability of the CHB-PET. To address these issues, a CHB-PET topology is proposed in this paper. The novel topology exploits the concept of multi-frequency modulation to achieve power decoupling and power unit multiplexing through reasonable LC resonant frequency selection, which optimizes the ISOP structure and ultimately reduces the hardware cost and size of the CHB-PET. In this study, the effectiveness of reducing the number of power switching devices and HFT is firstly analyzed, and after describing its working principle, the control strategy of each power conversion link of PET is discussed before the correctness and effectiveness of the CHB-PET topology and control strategy proposed in this paper are verified via simulation. [ABSTRACT FROM AUTHOR]

Background: The outcomes of patients with tumors of the thoracolumbar spine treated with en bloc resection (EBR) using three-dimensional (3D)-printed endoprostheses are underreported. Methods: We retrospectively evaluated patients with thoracolumbar tumors who underwent surgery at our institution. Logistic regression analysis was performed to identify the potential risk factors for surgical complications. Nomograms to predict complications were constructed and validated. Results: A total of 53 patients with spinal tumors underwent EBR at our hospital; of these, 2 were lost to follow-up, 45 underwent total en bloc spondylectomy, and 6 were treated with sagittal en bloc spondylectomy. The anterior reconstruction materials included a customized 3D-printed artificial vertebral body (AVB) in 10 cases and an off-the-shelf 3D-printed AVB in 41 cases, and prosthesis mismatch occurred in 2 patients reconstructed with the off-the-shelf 3D-printed AVB. The median follow-up period was 21 months (range, 7–57 months). Three patients experienced local recurrence, and 5 patients died at the final follow-up. A total of 50 perioperative complications were encountered in 29 patients, including 25 major and 25 minor complications. Instrumentation failure occurred in 1 patient, and no prosthesis subsidence was observed. Using a combined surgical approach was a dependent predictor of overall complications, while Karnofsky performance status score, lumbar spine lesion, and intraoperative blood loss ≥ 2000 mL were predictors of major complications. Nomograms for the overall and major complications were constructed using these factors, with C-indices of 0.850 and 0.891, respectively. Conclusions: EBR is essential for the management of thoracolumbar tumors; however, EBR has a steep learning curve and a high complication rate. A 3D-printed AVB is an effective and feasible reconstruction option for patients treated with EBR. [ABSTRACT FROM AUTHOR]

Purpose. Severe hemorrhage after percutaneous nephrolithotomy (PCNL) is a rare but alerting event. In this study, we report the factors affecting massive hemorrhage after PCNL, various levels of vascular damage during renal angiography, and the therapeutic effect of superselective renal artery embolization (SRAE). Patients and Methods. A retrospective analysis was performed on the data of 69 patients with postoperative PCNL hemorrhage who underwent SRAE from January 2010 to March 2021. Inclusion criteria for all cases were failure of conservative treatment for severe renal hemorrhage after surgery and then treatment with SRAE. In addition, 98 patients without significant hemorrhage after PCNL were randomly selected as the control group. All clinical data are confirmed by imaging and laboratory examinations. We performed univariate and multivariate analyses to find risk factors of massive hemorrhage and high-grade renal vascular injury after PCNL. Results. A total of 69 patients underwent angiography, 64 of which received SRAE due to positive hemorrhages detected by angiography. Urinary tract infection (OR (95% CI) = 11.214 (2.804∼44.842)), high blood pressure (OR (95% CI) = 5.686 (1.401∼23.083)), and no hydronephrosis (OR (95% CI) = 0.189 (0.049∼0.724)) are the most important factors leading to massive hemorrhage after PCNL. In patients who need SRAE after hemorrhage, high-grade vascular injury (grade III) is related to advanced age and decreased hemoglobin. Conclusion. During the perioperative period of PCNL, patients with a risk of hypertension, urinary tract infection, and no hydronephrosis should be strengthened to monitor their high risk of postoperative hemorrhage. For patients with postoperative hemorrhage, we can use the patient's age and decreased hemoglobin before and after operation for analysis. In this way, individualized assessment can greatly improve the efficiency of SRAE treatment. [ABSTRACT FROM AUTHOR]

Ureteral stents are commonly used in urology but are frequently associated with hematuria, abdominal discomfort, urinary tract infection, stent displacement, and stent encrustation. Surface modification of ureteral stents is beneficial to solve the problem, and these can be divided into coated stents and drug-eluting stents according to the modification method. Coated stents can be divided into hydrophilic coatings, antibacterial coatings, and anti-encrustation coatings. Drug-eluting stents can be divided into antimicrobial drug-eluting, antispasmodic analgesic drug-eluting, anti-ureteral stricture drug-eluting, and anti-tumor drug-eluting. Surface modification of ureteral stents can not only reduce complications related to ureteral stents but also strengthen the treatment of certain urologic diseases, which has a high clinical application value. This review focuses on highlighting and summarizing the latest research progress about surface modification of ureteral stents, ureteral stent development history, classification, functions, and future development prospects. The purpose of this article is to discuss surface modification of ureteral stents to reduce stent-related complications and potential research directions for the treatment of urinary tract tumors are also briefly discussed, to help guide further innovation in ureteral stent coatings, which contribute to the future progress of ureteral stents surface modification. [ABSTRACT FROM AUTHOR]

Lincomycin is a broad-spectrum antibiotic and particularly effective against Gram-positive pathogens. Albeit familiar with the biosynthetic mechanism of lincomycin, we know less about its regulation, limiting the rational design for strain improvement. We therefore analyzed two-component systems (TCSs) in Streptomyces lincolnensis, and selected eight TCS gene(s) to construct their deletion mutants utilizing CRISPR/Cas9 system. Among them, lincomycin yield increased in two strains (Δ3900–3901 and Δ5290–5291) while decreased in other four strains (Δ3415–3416, Δ4153–4154, Δ4985, and Δ7949). Considering the conspicuous effect, SLINC_5291-5290 (AflQ1-Q2) was subsequently studied in detail. Its repression on lincomycin biosynthesis was further proved by gene complementation and overexpression. By binding to a 16-bp palindromic motif, the response regulator AflQ1 inhibits the transcription of its encoding gene and the expression of eight operons inside the lincomycin synthetic cluster (headed by lmbA, lmbJ, lmbK, lmbV, lmbW, lmbU, lmrA, and lmrC), as demonstrated by quantitative RT-PCR and electrophoretic mobility shift assays. Besides, the regulatory genes including bldD, glnR, lcbR1, and ramR are also regulated by the TCS. According to the screening towards nitrogen sources, aspartate affects the regulatory behavior of histidine kinase AflQ2. And in return, AflQ1 accelerates aspartate metabolism via ask-asd, asd2, and thrA. In summary, we acquired six novel regulators related to lincomycin biosynthesis, and elucidated the regulatory mechanism of AflQ1-Q2. This highly conserved TCS is a promising target for the construction of antibiotic high-yield strains. Key points: • AflQ1-Q2 is a repressor for lincomycin production. • AflQ1 modulates the expression of lincomycin biosynthetic and regulatory genes. • Aspartate affects the behavior of AflQ2, and its metabolism is promoted by AflQ1. [ABSTRACT FROM AUTHOR]

A wearable self-powered biosensor, fabricated from a stretchable and bendable textile matrix, senses glucose in urine. This textile matrix is made of cellulose fibers. A porous three-dimensional electrode with high flexibility, conductivity, and electroactive surface area is obtained by coating multi-wall carbon nanotubes and reduced graphene oxides onto a textile matrix based on cellulose fibers. After immobilizing glucose oxidase and laccase by the polymer embed method, the bioelectrodes show good enzymatic loading density and high electrocatalytic efficiency. The relative self-powered biosensor has a good linear response to glucose in the concentration range from 0 to 40 mM (R2 = 0.995), with a satisfactory limit of detection at 3.95 mM, owing to the high electrocatalytic efficiency of the bioelectrodes. The biosensors have good selectivity, repeatability, and long-term storage stability, exhibit excellent stretching and bending performance, and show stability to a variety of pH, because of the catalytic specificity and tolerance of enzymes, the reasonable design of the biosensor, and the stable catalytic microenvironment. The recovery of the biosensor integrated with a diaper for glucose in artificial urine samples is between 95.6 and 105.9%, suggesting a promising determination for real samples. [ABSTRACT FROM AUTHOR]

Data science has revolutionized the paradigms of medical decision-making. In the past, medical data could not be recorded and stored indefinitely. In the present day, huge volumes of medical data have been collected electronically, such as medical records, medical images, and heterogeneous surgical data. Under this condition, how to help the radiologists diagnose the thyroid cancer by using the accumulated examination reports and pathologic findings has been a challenge needing to face. From the analysis of historical examination reports, the problem of diagnosing thyroid cancer is evidently considered as a multi-criteria decision-making problem. Thus, a data-driven fusion method of weights and reliabilities in decision-making is proposed in this paper to cope with the above challenge. Linguistic term sets are introduced to model and portray the assessments on each criterion in the problem of diagnosing thyroid cancer by using three types of linguistic scale functions. A data-driven way is then designed to determine the weights and reliabilities of the assessments on each criterion for each radiologist by considering the similarity between the assessments on each criterion and the overall assessments and the similarity between the assessments on criterion and the golden standard, which are derived from the historical data. Subsequently, assessments on each criterion will be combined with the weights and reliabilities to generate a data-driven solution to the problem. The applicability and effectiveness of the data-driven fusion method are verified by solving a real problem of diagnosing thyroid cancer using historical data collected from five radiologists in a tertiary hospital from January 2011 to February 2019. [ABSTRACT FROM AUTHOR]

Aims: Assessing the role of ramRsl, a gene absent in a lincomycin over‐producing strain, in the regulation of morphological development and lincomycin biosynthesis in Streptomyces lincolnensis. Methods and Results: The gene ramRsl was deleted from the wild‐type strain NRRL 2936 and the ΔramR mutant strain was characterized by a slower growth rate and a delayed morphological differentiation compared to the original strain NRRL 2936. Furthermore, the ΔramR produced 2.6‐fold more lincomycin than the original strain, and consistently the level of expression of all lincomycin cluster located genes was enhanced at 48 and 96 h in the ΔramR. Complementation of ΔramR with an intact copy of ramRsl restored all wild‐type features, whereas the over‐expression of ramRsl led to a reduction of 33% of the lincomycin yield. Furthermore, the level of expression of glnR, bldA and SLCG_2919, three of known lincomycin biosynthesis regulators, was lower in the ΔramR than in the original strain at the early stage of fermentation and we demonstrated, using electrophoretic mobility shift assay and XylE reporter assay, that glnR is a novel direct target of RamR. Conclusions: Altogether, these results indicated that, beyond promoting the morphological development, RamR regulates negatively lincomycin biosynthesis and positively the expression of the nitrogen regulator GlnR. Significance and Impact of the Study: We demonstrated that RamR plays a negative role in the regulation of lincomycin biosynthesis in S. lincolnensis. Interestingly, the deletion of this gene in other antibiotic‐producing Streptomyces strains might also increase their antibiotic‐producing abilities. [ABSTRACT FROM AUTHOR]

Background: Although hepatitis B virus (HBV) is a recognized risk factor for renal diseases, little is known about HBV infection in individuals with upper urinary calculi (UUC). We investigated the relationship between chronic HBV infection and UUC. Methods: We retrospectively analysed data from 1399 patients who were discharged from the Department of Urology (2017–2018). The diagnosis of UUC was determined using urinary tract ultrasonography or computed tomography, and HBV infection was evaluated by a positive hepatitis B surface antigen (HBsAg) test. Data on patients with and without UUC and HBsAg-positive and HBsAg-negative patients were compared by univariate and multivariate analyses. Results: Data on chronic HBV infection and UUC were available for 1062 patients, including 514 who presented with UUC and 548 who did not. Overall, 5.8% of total patients, 8.0% of UUC patients and 3.8% of non-UUC patients had chronic HBV infection. UUC patients (41/514) had a significantly higher prevalence of HBsAg positivity (OR 2.175; 95% CI 1.267–3.734; P = 0.004) than non-UUC patients (21/548). After stratifying by sex, the relative odds of HBsAg positivity were statistically significant in men (OR 2.156; 95% CI 1.162–4.003; P = 0.015) but not in women (OR 2.947; 95% CI 0.816–10.643; P = 0.099). The incidence of urinary pH > 6 and staghorn stones was significantly higher in HBsAg-positive UUC patients than in HBsAg-negative UUC patients. Conclusion: This is the first study to demonstrate that chronic HBV infection is strongly associated with UUC, at least in men. The urinary pH > 6 and staghorn stones were more common in UUC patients with chronic HBV infection. [ABSTRACT FROM AUTHOR]

Background: Although hepatitis B virus (HBV) is a recognized risk factor for renal diseases, little is known about HBV infection in individuals with upper urinary calculi (UUC). We investigated the relationship between chronic HBV infection and UUC.Methods: We retrospectively analysed data from 1399 patients who were discharged from the Department of Urology (2017-2018). The diagnosis of UUC was determined using urinary tract ultrasonography or computed tomography, and HBV infection was evaluated by a positive hepatitis B surface antigen (HBsAg) test. Data on patients with and without UUC and HBsAg-positive and HBsAg-negative patients were compared by univariate and multivariate analyses.Results: Data on chronic HBV infection and UUC were available for 1062 patients, including 514 who presented with UUC and 548 who did not. Overall, 5.8% of total patients, 8.0% of UUC patients and 3.8% of non-UUC patients had chronic HBV infection. UUC patients (41/514) had a significantly higher prevalence of HBsAg positivity (OR 2.175; 95% CI 1.267-3.734; P = 0.004) than non-UUC patients (21/548). After stratifying by sex, the relative odds of HBsAg positivity were statistically significant in men (OR 2.156; 95% CI 1.162-4.003; P = 0.015) but not in women (OR 2.947; 95% CI 0.816-10.643; P = 0.099). The incidence of urinary pH > 6 and staghorn stones was significantly higher in HBsAg-positive UUC patients than in HBsAg-negative UUC patients.Conclusion: This is the first study to demonstrate that chronic HBV infection is strongly associated with UUC, at least in men. The urinary pH > 6 and staghorn stones were more common in UUC patients with chronic HBV infection. [ABSTRACT FROM AUTHOR]

Recently, an increasing number of investigators have debated the wide rule of the puncture to renal papilla in PCNL. We evaluated the effect of renal papillary and nonpapillary puncture on bleeding in an in vitro porcine kidney experience, with the aim of determining the safe puncture sites of collecting system in PCNL. A total of 70 fresh porcine kidneys were selected and subjected to nephrostomy. We performed a puncture through a renal papilla, infundibulum, renal column, or minor calyceal neck (including the front, back, up, and down). The primary outcome was the amount of bleeding. The results showed that the papillary puncture group yielded minimal bleeding (1.59 ± 1.01 ml/min) compared with the infundibular puncture group (6.25 ± 4.46 ml/min, P <.001), renal column puncture group (4.24 ± 3.79 ml/min, P = 0.001), and minor calyceal neck puncture group (2.27 ± 1.35 ml/min, P = 0.011). However, after stratifying by orientation, the up (1.75 ± 0.80 ml/min, P = 0.501) or down (1.77 ± 0.72 ml/min, P = 0.437) minor calyceal neck puncture group and papillary puncture group yielded comparable bleeding. In summary, nonpapillary puncture must be carefully considered. Infundibular and renal column punctures were inferior to papillary puncture, and up or down minor calyceal neck puncture may be a prudent choice in specific situations. [ABSTRACT FROM AUTHOR]

Purpose: Severe haemorrhage in percutaneous nephrolithotomy (PCNL) is an alarming event, and preventing injury to renal major vessels is a challenge. We evaluated the efficiency of a blunt needle in renal puncture procedures. Methods: We first retrospectively reviewed the embolization images of post-PCNL patients to analyse the types of arteries injured, which were considered target arteries. Then, either a blunt needle or a conventional needle was used to directly puncture target arteries in ex vivo porcine kidneys and to establish renal access ex vivo and in vivo. The primary outcome was the incidence of target artery injuries, which were observed by digital subtraction angiography, nephroscopy and 3-dimensional endocasts. The secondary outcome was the rate of excreted fluid per access. Results: The segmental and interlobar arteries were the most common types of injured arteries that needed to be embolized after PCNL. When these arteries were punctured directly, blunt needles reduced injury (1/20 vs. 16/20; OR 4.750; 95% CI 1.966–11.478; P <.001) by 76% compared to injuries induced by conventional needles. Moreover, the blunt needle group also had a significantly lower incidence of these arteries' injuries ex vivo due to renal puncture and yielded a lower rate of excreted fluid in ex vivo and in vivo renal puncture procedures. Conclusion: A blunt needle for renal puncture can be effective in reducing injury to renal major arteries and the accompanying haemorrhage. We propose the concept of blunt puncture, which may be a promising method for achieving safe renal access in PCNL. [ABSTRACT FROM AUTHOR]

Lincomycin is an important antimicrobial agent which is widely used in clinical and animal husbandry. The biosynthetic pathway of lincomycin comes to light in the past 10 years, however, the regulatory mechanism is still unclear. In this study, a redox‐sensing regulator Rex from Streptomyces lincolnensis (Rexlin) was identified and characterized to affect cell growth and lincomycin biosynthesis. Disruption of rex resulted in an increase in cell growth, but a decrease in lincomycin production. The results of quantitative real‐time polymerase chain reaction showed that Rexlin can promote transcription of the regulatory gene lmbU and the structural genes lmbA, lmbC, lmbJ, lmbV, and lmbW. However, electrophoretic mobility shift assay analysis demonstrated that Rexlin can not bind to the promoter regions of these genes above. Findings in this study broadened our horizons in the regulatory mechanism of lincomycin production and laid a foundation for strain improvement of antibiotic producers. [ABSTRACT FROM AUTHOR]

The interactions of dopamine hydrochloride (DH) with urea were investigated by electrochemical cyclic voltammetry, density functional theory (DFT) and quantum theory of atoms in molecules (QTAIM) analysis. Changes of the oxidation/reduction peak potentials of DH in DH-urea-H2O systems indicated that the hydrogen bonds were formed between DH and urea. The DFT and QTAIM results confirmed that the hydrogen and oxygen atoms on phenolic hydroxyl groups, the hydrogen atoms on NH3+ and the aromatic ring of DH can form hydrogen bond with the oxygen and hydrogen atoms of urea. Moreover, the solution pH has an effect on the electrochemical behaviour of DH in the system. [ABSTRACT FROM AUTHOR]

The yigP (ubiJ) locus has been shown to be associated with many phenotypic changes in Escherichia coli, while the individual function of its two products, EsrE small RNA and UbiJ protein, is still elusive. In this study, we constructed two single‐element mutants, EsrE mutant strain Mut and UbiJ mutant strain Ter, on the basis of the base substitution programs. The variable antibiotics resistance and ubiquinone (UQ, coenzyme Q) yield and the similar cell growth between mutants revealed the division of labor and collaboration of EsrE and UbiJ in JM83. Furthermore, we detected the concentration of intracellular proteins of Mut and Ter by stable isotope‐labeled quantitative proteomics. The results demonstrate that both EsrE and UbiJ are involved in the aerobic growth of E. coli, while EsrE preferentially contributes to the amino acid‐related pathway, and UbiJ is an indispensable factor in the biosynthesis of UQ. Moreover, we uncovered a potential regulatory circuit of d‐cycloserine (DCS) that composed of EsrE, GcvA, and GcvB by proteomic analysis. [ABSTRACT FROM AUTHOR]

Lincomycin is one of the most important antibiotics in clinical practice. To further understand the regulatory mechanism on lincomycin biosynthesis, we investigated a pleiotropic transcriptional regulator AdpAlin in the lincomycin producer Streptomyces lincolnensis NRRL 2936. Deletion of adpA lin (which generated Δ adpA lin ) interrupted lincomycin biosynthesis and impaired the morphological differentiation. We also found that putative AdpA binding sites were unusually scattered in the promoters of all the 8 putative operons in the lincomycin biosynthetic gene cluster (BGC). In Δ adpA lin , transcript levels of structural genes in 8 putative operons were decreased with varying degrees, and electrophoretic mobility shift assays (EMSAs) confirmed that AdpAlin activated the overall putative operons via directly binding to their promoter regions. Thus, we speculated that the entire lincomycin biosynthesis is under the control of AdpAlin. Besides, AdpAlin participated in lincomycin biosynthesis by binding to the promoter of lmbU which encoded a cluster sited regulator (CSR) LmbU of lincomycin biosynthesis. Results of qRT-PCR and catechol dioxygenase activity assay showed that AdpAlin activated the transcription of lmbU. In addition, AdpAlin activated the transcription of the bldA by binding to its promoter, suggesting that AdpAlin indirectly participated in lincomycin biosynthesis and morphological differentiation. Uncommon but understandable, AdpAlin auto-activated its own transcription via binding to its own promoter region. In conclusion, we provided a molecular mechanism around the effect of AdpAlin on lincomycin biosynthesis in S. lincolnensis , and revealed a cascade regulation of lincomycin biosynthesis by AdpAlin, LmbU, and BldA. [ABSTRACT FROM AUTHOR]

UV-Vis absorption spectra, cyclic voltammetry and 1H nuclear magnetic resonance (1H NMR) spectra were applied to explore the hydrogen bond interactions of p-aminophenol hydrochloride (PAH) with H2O. The results indicated the hydrogen bonds were formed in PAH–H2O system. The anodic/cathodic peak potentials and UV-Vis absorption bands of PAH in H2O could be affected due to the interactions. The results of density functional theory, atoms in molecules theory and natural bond orbital analyses further confirmed the existence of hydrogen bonds between the phenolic hydroxyl, –NH3+ protons and Cl− of PAH and H2O. Furthermore, the π-π stacking was suggested between PAH benzene rings from the 1H NMR spectra at higher concentrations. [ABSTRACT FROM AUTHOR]

The majority of benign meningiomas exhibit a slow growth rate and are associated with a good prognosis. The recurrence and extracranial metastases of meningioma are rare. The present report describes the case of a patient with recurrence of transitional meningioma for which total resection had been performed 8 years prior. Furthermore, the transitional meningioma transformed into atypical meningioma, and metastasized to the ribs. The present report aimed to describe the clinical features and pathological findings of a case of malignant transformation and distant metastasis of benign meningioma. A review of the literature was also performed. [ABSTRACT FROM AUTHOR]

Global regulator BldA, the only tRNA for a rare leucine codon UUA, is best known for its ability to affect morphological differentiation and secondary metabolism in the genus Streptomyces. In this study, we confirmed the regulatory function of the bldA gene (Genbank accession no. EU124663.1) in Streptomyces lincolnensis. Disruption of bldA hinders the sporulation and lincomycin production, that can recur when complemented with a functional bldA gene. Western blotting assays demonstrate that translation of the lmbB2 gene which encodes a L-tyrosine hydroxylase is absolutely dependent on BldA; however, mistranslation of the lmbU gene which encodes a cluster-situated regulator (CSR) is observed in a bldA mutant. Intriguingly, when the preferential cognate codon CTG was used, the expression level of LmbU was not the highest compared to the usage of rare codon TTA or CTA, indicating the rare codon in this position is significant for the regulation of lmbU expression. Moreover, replacement of TTA codons in both genes with another leucin codon in the bldA mutant did not restore lincomycin production. Thus, we believe that the bldA gene regulates lincomycin production via controlling the translation of not only lmbB2 and lmbU, but also the other TTA-containing genes. In conclusion, the present study demonstrated the importance of the bldA gene in morphological differentiation and lincomycin production in S. lincolnensis. [ABSTRACT FROM AUTHOR]

The authors report a non-enzymatic electrochemical sensor based on a sliver nanoparticle-decorated carbon nanotube (AgNPs-MWCNT). Highly-dispersed AgNPs were loaded on the MWCNT surface though a simple and facile two-step method. The morphology, components, and the size of the AgNPs-MWCNT nanocomposite were characterized by transmission electron microscopy, X-ray diffraction, and ICP analysis. Benefitting from the synergistic effect between the AgNPs and MWCNT, the AgNPs-MWCNT nanocomposite exhibited high electrocatalytic activity for H2O2; the AgNPs-MWCNT electrochemical sensor was prepared by coating the AgNPs-MWCNT nanocomposite on a glassy carbon electrode, and it showed a fast and sensitive response to H2O2 with a linear range of 1 to 1000 μM. The detection limit was 0.38 μM (S/N = 3). The sensor was applied to detect H2O2 in spiked human blood serum samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Prophage enriched the prokaryotic genome, and their transcriptional factors improved the protein expression network of the host. In this study, we uncovered a new prophage-prophage interaction in E. coli JM83. The Rac prophage protein RacR (GenBank accession no. AVI55875.1) directly activated the transcription of φ80dlacZΔM15 prophage lysozyme encoding gene 19 (GenBank accession no. ACB02445.1, renamed it lysN, lysozyme nineteen), resulting in the growth defect of JM83. This phenomenon also occurred in DH5α, but not in BL21(DE3) and MG1655 due to the genotype differences. However, deletion of lysN could not completely rescued JM83 from the growth arrest, indicating that RacR may regulate other related targets. In addition, passivation of RacR regulation was found in the late period of growth of JM83, and it was transmissible to daughter cells. Altogether, our study revealed part of RacR regulatory network, which suggested some advanced genetic strategies in bacteria. [ABSTRACT FROM AUTHOR]