Oligomeric interactions maintain active-site structure in a noncooperative enzyme family.

The evolutionary benefit accounting for widespread conservation of oligomeric structures in proteins lacking evidence of intersubunit cooperativity remains unclear. Here, crystal and cryo-EM structures, and enzymological data, demonstrate that a conserved tetramer interface maintains the active-site structure in one such class of proteins, the short-chain dehydrogenase/reductase (SDR) superfamily. Phylogenetic comparisons support a significantly longer polypeptide being required to maintain an equivalent active-site structure in the context of a single subunit. Oligomerization therefore enhances evolutionary fitness by reducing the metabolic cost of enzyme biosynthesis. The large surface area of the structure-stabilizing oligomeric interface yields a synergistic gain in fitness by increasing tolerance to activity-enhancing yet destabilizing mutations. We demonstrate that two paralogous SDR superfamily enzymes with different specificities can form mixed heterotetramers that combine their individual enzymological properties. This suggests that oligomerization can also diversify the functions generated by a given metabolic investment, enhancing the fitness advantage provided by this architectural strategy.

Interlamellar-Spacing Engineering of Stable and Toxicity-Reduced 2D Perovskite Single Crystal for High-Resolution X-ray Imaging.

Two-dimensional (2D) lead halide perovskites are excellent candidates for X-ray detection due to their high resistivity, high ion migration barrier, and large X-ray absorption coefficients. However, the high toxicity and long interlamellar distance of the 2D perovskites limit their wide application in high sensitivity X-ray detection. Herein, we demonstrate stable and toxicity-reduced 2D perovskite single crystals (SCs) realized by interlamellar-spacing engineering via a distortion self-balancing strategy. The engineered low-toxicity 2D SC detectors achieve high stability, large mobility-lifetime product, and therefore high-performance X-ray detection. Specifically, the detectors exhibit a record high sensitivity of 13488 µC Gy1- cm-2, a low detection limit of 8.23 nGy s-1, as well as a high spatial resolution of 8.56 lp mm-1 in X-ray imaging, all of which are far better than those of the high-toxicity 2D lead-based perovskite detectors. These advances provide a new technical solution for the low-cost fabrication of low-toxicity, scalable X-ray detectors.

Renal anatomical classification systems cannot predict the occurrence of vascular complications after partial nephrectomy.

OBJECTIVES: To determine the relationship between renal tumor complexity and vascular complications after partial nephrectomy using PADUA, RENAL, and ZS scores. METHODS: Between January 2007 and December 2018, a total of 1917 patients with available cross-sectional imaging were enrolled in the study. Logistic regressions were used to identify independent predictors of vascular complications. RESULTS: Of 1917 patients, 31 (1.6%) developed vascular complications, including 10 females and 21 males. The high-complexity category was significantly associated with a decreased risk of vascular complication in PADUA (OR = 0.256; 95%CI = 0.086-0.762; P = 0.014) and ZS score (OR = 0.279; 95%CI = 0.083-0.946; P = 0.040). Laparoscopic partial nephrectomy and robot-assisted laparoscopic partial nephrectomy were independent risk factors for vascular complications. Meanwhile, the incidence was significantly reduced in the recent 4 years in the high score tumor group alone in PADUA (0.2% [1/474] vs. 2.2% [3/139], P = 0.038) and ZS score (0.2% [1/469] vs. 2.7% [3/112], P = 0.024). In the first 8 years, laparoscopic partial nephrectomy and robot-assisted laparoscopic partial nephrectomy were the only two independent risk factors for vascular complications. In the recent 4 years, only the high-complexity category was significantly associated with a decreased risk of vascular complication in the PADUA score (OR = 0.110; 95%CI = 0.013-0.938; P = 0.044). CONCLUSION: The renal anatomic classification system cannot predict the occurrence of vascular complications after partial nephrectomy.

Shear wave elastography-based deep learning model for prognosis of patients with acutely decompensated cirrhosis.

PURPOSE: This study aimed to develop and validate a deep learning model based on two-dimensional (2D) shear wave elastography (SWE) for predicting prognosis in patients with acutely decompensated cirrhosis. METHODS: We prospectively enrolled 288 acutely decompensated cirrhosis patients with a minimum 1-year follow-up, divided into a training cohort (202 patients, 1010 2D SWE images) and a test cohort (86 patients, 430 2D SWE images). Using transfer learning by Resnet-50 to analyze 2D SWE images, a SWE-based deep learning signature (DLswe) was developed for 1-year mortality prediction. A combined nomogram was established by incorporating deep learning SWE information and laboratory data through a multivariate Cox regression analysis. The performance of the nomogram was evaluated with respect to predictive discrimination, calibration, and clinical usefulness in the training and test cohorts. RESULTS: The C-index for DLswe was 0.748 (95% CI 0.666-0.829) and 0.744 (95% CI 0.623-0.864) in the training and test cohorts, respectively. The combined nomogram significantly improved the C-index, accuracy, sensitivity, and specificity of DLswe to 0.823 (95% CI 0.763-0.883), 86%, 75%, and 89% in the training cohort, and 0.808 (95% CI 0.707-0.909), 83%, 74%, and 85% in the test cohort (both p < 0.05). Calibration curves demonstrated good calibration of the combined nomogram. Decision curve analysis indicated that the nomogram was clinically valuable. CONCLUSIONS: The 2D SWE-based deep learning model holds promise as a noninvasive tool to capture valuable prognostic information, thereby improving outcome prediction in patients with acutely decompensated cirrhosis.

Does intraoperative cyst rupture of malignant cystic renal masses really have no negative impact on oncologic outcomes?

BACKGROUND: To assess the impact of malignant cystic renal masses (CRM) rupture on oncologic outcomes. METHODS: The study included 406 cases with partial nephrectomy (PN) and 17 cases with cyst decortication confirmed as malignant CRM by pathology. Recurrence-free survival (RFS), metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival (OS) were analyzed by the Kaplan-Meier method and log-rank test. Cox regression was used to identify risk factors associated with RFS, MFS, CSS, and OS. Logistic regression was performed to explore predictors of rupture. RESULTS: Tumor rupture occurred in 32 of 406 cases (7.9%). With median follow-up of 43 months, 4 (12.5%) and 5 (1.3%) cases experienced recurrence in rupture and non-rupture group, respectively (P = 0.003). Estimated RFS, MFS, and CSS were shorter in cyst ruptured (CR) group than non-ruptured (nonCR) cases (P < 0.001; P = 0.001; P < 0.001). Cox regression analysis indicated that CR was an independent prognostic factor for RFS (HR = 7.354; 95% CI = 1.839-29.413; P = 0.005), MFS (HR = 8.069; 95% CI = 1.804-36.095; P = 0.006), and CSS (HR = 9.643; 95% CI = 2.183-42.599; P = 0.003). Multivariable logistic regression showed that Bosniak IV was a protective factor for CR (OR = 0.065; 95% CI = 0.018-0.239; P < 0.001). However, compared to Bosniak III and I-IIF, Bosniak IV CRMs showed higher rate of clear cell renal cell carcinoma (ccRCC) (76.8% vs 36.5% vs 81.4%) (P < 0.001) and lower rate of Fuhrman I staging (11.2% vs 66.7% vs 7.4%) (P < 0.001). Therefore, in ruptured cases, the recurrence rate was higher in CRM with Bosniak IV (50%, 2/4) than Bosniak I-III (4.4%, 2/45) (P = 0.029). CONCLUSIONS: Intraoperative malignant CRM rupture had negative impacts on oncologic outcomes. Bosniak IV was more aggressive than Bosniak I-III and had a higher risk of recurrence after rupture. However, Bosniak IV had a lower risk of rupture, which could weaken even cover-up of the true effect of tumor rupture on oncologic outcomes.

Tumor contour irregularity on preoperative imaging: a practical and useful prognostic parameter for papillary renal cell carcinoma.

OBJECTIVES: To illustrate tumor contour irregularity on preoperative imaging with a practical method and further determine its value in predicting disease-free survival (DFS) in patients with pRCC (papillary renal cell carcinoma). METHODS: We performed a retrospective single-institution review of 267 Chinese pRCC patients between March 2009 and May 2019. Contour irregularity on cross-section was classified into smooth but distorted margin, unsmooth and sharply nodular margin, and blurred margin. Then, the ratio of the cross-section numbers of irregularity and the total tumor was defined as the contour irregular degree (CID). Cox regression and Kaplan-Meier analysis were performed to analyze the impact of CID on DFS. Then, the prognostic performance of CID was compared with pRCC risk stratification published by Leibovich et al. RESULTS: The median follow-up was 45 months (IQR: 23-69), in which 27 (10%) patients had metastasis or recurrence. Observed DFS rates were 95%, 90%, and 88% at 1, 3, and 5 years. The CID was an independent prognostic factor of DFS (HR = 1.048, 95% CI = 1.029-1.068, p < 0.001). The Kaplan-Meier plot showed that high-risk patients (CID ≥ 50%) tended to have a significantly shorter DFS (p < 0.001). The CID and Leibovich's pRCC model for DFS prediction had a C-index of 0.934 (95% CI = 0.907-0.961) and 0.833 (95% CI = 0.739-0.927) respectively. CONCLUSIONS: With our standard and practical method, the CID can be a reliable imaging marker for DFS prediction in patients with pRCC. KEY POINTS: • The updated contour irregularity was an independent parameter for predicting disease-free survival in patients with pRCC. • High-risk pRCC patients (contour irregular degree ≥ 50%) tended to have a shorter disease-free survival. • Tumor contour irregularity in pRCC risk stratification outperformed Leibovich's model from our cohort.

Screening of potential vaccine candidates against pathogenic Brucella spp. using compositive reverse vaccinology.

Brucella spp. are Gram-negative, facultative intracellular bacteria that cause brucellosis in humans and various animals. The threat of brucellosis has increased, yet currently available live attenuated vaccines still have drawbacks. Therefore, subunit vaccines, produced using protein antigens and having the advantage of being safe, cost-effective and efficacious, are urgently needed. In this study, we used core proteome analysis and a compositive RV methodology to screen potential broad-spectrum antigens against 213 pathogenic strains of Brucella spp. with worldwide geographic distribution. Candidate proteins were scored according to six biological features: subcellular localization, antigen similarity, antigenicity, mature epitope density, virulence, and adhesion probability. In the RV analysis, a total 32 candidate antigens were picked out. Of these, three proteins were selected for assessment of immunogenicity and preliminary protection in a mouse model: outer membrane protein Omp19 (used as a positive control), type IV secretion system (T4SS) protein VirB8, and type I secretion system (T1SS) protein HlyD. These three antigens with a high degree of conservation could induce specific humoral and cellular immune responses. Omp19, VirB8 and HlyD could substantially reduce the organ bacterial load of B. abortus S19 in mice and provide varying degrees of protection. In this study, we demonstrated the effectiveness of this unique strategy for the screening of potential broad-spectrum antigens against Brucella. Further evaluation is needed to identify the levels of protection conferred by the vaccine antigens against wild-type pathogenic Brucella species challenge.

Prevalence and related factors of depression and falls among the elderly living in rural communities of Guangzhou.

Few studies have concentrated on the prevalence and related factors of depression and falls among the elderly living in rural communities of Guangzhou. A total of 335 participants aged ≥60 years were recruited by simple random sampling method. A structural equation model was applied to determine interrelationships between depression, falls and other variables. As high as 27.5% and 23.3% participants had reported depressive symptoms and falls, respectively. The path analysis showed the total effect (ß = -0.58) of depression on quality of life (QOL) consisted of a direct effect (ß = -0.51) and an indirect effect (ß = -0.07), which was mediated by family function and number of falls, and the R2 was 0.36. The model fit indices were χ2/df = 1.096, P > 0.05, Root Mean Square Error of Approximation (RMSEA) = 0.017, Tucker-Lewis Index (TLI) = 0.998 and Comparative Fit Index (CFI) = 0.999. Depression and falls were prevalent among the elderly living in rural communities of Guangzhou city. Pay attention to strengthen family function and prevent falls may prevent depression and improve the QOL among the elderly.

Development and prospective validation of a novel weighted quantitative scoring system aimed at predicting the pathological features of cystic renal masses.

OBJECTIVES: To develop and prospectively validate a novel weighted quantitative scoring system based on CT findings, namely, the renal cyst index (RCI), aimed at preoperatively predicting the pathological features of cystic renal masses (CRMs). METHODS: The RCI was based on four critical features of CRMs: the cyst wall, septal, nodule, and cyst contents. These parameters were scored with 1, 2, or 3 points. Weight coefficients for these parameters were determined by the multivariable logistic regression. The odds ratio (OR) and 95% confidence interval (95% CI) were used to summarise the results. The RCI was defined as the sum of these four weight coefficients. Malignancy risk prediction models were built based on the retrospective evaluation of 441 patients. We also compared the prediction ability of the RCI with the Bosniak classification in the 441 patients and applied these novel models to 152 masses resected in our institution to prospectively validate the efficiency of the RCI. RESULTS: The wall point (OR = 5.71 [95% CI = 1.734-18.808, p = 0.004, point = 2], OR = 12.665 [95% CI = 3.750-42.770, p < 0.001, point = 3]), septal point (OR = 3.325 [95% CI = 1.272-8.692, p = 0.014, point = 3]), nodule point (OR = 4.588 [95% CI = 1.429-14.729, p < 0.001, point = 2], OR = 17.032 [95% CI = 5.017-57.820, p = 0.010, point = 3]), content point (OR = 22.822 [95% CI = 1.041-495.995, p = 0.047, point = 2], OR = 2.723 [95% CI = 1.296-10.696, p = 0.015, point = 3]), and RCI (OR = 1.247 [95% CI = 1.197-1.299, p < 0.001]) were significantly associated with malignancy. Masses with an RCI < 6 were regarded as benign masses; masses with an RCI ≥ 10 were regarded as malignant masses. The malignancy risk of masses with an RCI > 6 but < 10 were determined by a nomogram. The prediction ability of the RCI was significantly superior to the Bosniak classification for Bosniak IIF and III masses (AUC: 0.912 vs. 0.753, p = 0.001). The RCI also accurately predicted the pathological features of 152 masses. CONCLUSION: The RCI is a reliable quantitative scoring system in predicting the malignancy risk of CRMs, and it outperformed the Bosniak classification system in some ways. KEY POINTS: • The renal cyst index (RCI) is a useful weighted quantitative classification system based on CT findings for diagnosing cystic renal masses. • The RCI outperforms the Bosniak classification system in some ways, especially for Bosniak IIF and III masses. • Masses with an RCI < 6 can be regarded as a simple cyst, while those with an RCI > 10 can be regarded as malignant masses.

Responses of bladder smooth muscle to the stretch go through extracellular signal-regulated kinase (ERK)/p90 ribosomal S6 protein kinase (p90RSK)/Nuclear factor-κB (NF-κB) Pathway.

AIMS: The present study was designed to study changes and its potential mechanisms in human bladder smooth muscle subjected to stretch. METHODS: Bioinformatics analyses including differential expression analysis, overrepresentation enrichment analysis, principal component analysis, and weighted gene coexpression network analysis were used to analyze a microarray dataset (GSE47080) of partial bladder outlet obstruction (pBOO) in rat to find the potential changes of gene expressions. Bladder from pBOO model and human bladder smooth muscle cells (HBSMCs) subjected to sustained prolonged stretch were collected for Western blot analysis, real-time polymerase chain reaction, and fluorescence analysis to verify the changes of gene expressions and preliminarily study the potential role of signaling pathway regulation in treatment of pBOO. RESULTS: The bioinformatics analysis showed that chronic obstruction activated mitogen-activated protein kinase pathway and changed cytoskeleton structure in bladder smooth muscle. In in vivo experiments in mice, pBOO was verified by cystometry. Partial BOO activated the extracellular signal-regulated kinase (ERK)/p90 ribosomal S6 protein kinase (p90RSK)/nuclear factor-κB (NF-κB) signaling pathway in DM. The messenger RNA (mRNA) expressions of contractile phenotypic proteins increased after pBOO. In in vitro experiments of HBSMCs, mechanical stretch activated ERK/p90RSK/NF-κB in HBSMCs in a time-dependent manner. The mRNA expressions of α-smooth muscle actin and SM22 also increased and filamentous actin (F-actin) polymerization was enhanced as well. Inhibition of ERK/p90RSK/NF-κB pathway reversed mechanical stretch-induced changes of contractile phenotypic expression and F-action polymerization. CONCLUSIONS: Continuous stretch increases expressions of contractile phenotypic proteins and promotes the polymerization of F-actin. This process partially goes through ERK/p90RSK/NF-κB pathway.

Toll-like receptor 4 signalling regulates antibody response to adenoviral vector-based vaccines by imprinting germinal centre quality.

Adenoviral vectors (AdV) are considered promising candidates for vaccine applications. A prominent group of Toll-like receptors (TLRs) participate in the adenovirus-induced adaptive immune response, yet there is little information regarding the role of TLR4 in AdV-induced immune responses in recent literature. We investigated the function of TLR4 in both adaptive and innate immune responses to an AdV-based anthrax vaccine. By immunizing wild-type and TLR4 knockout (TLR4-KO) mice, we revealed the requirement of TLR4 in AdV-induced innate responses. We also showed that TLR4 functions are required for germinal centre responses in immunized mice, as expression of the apoptosis-related marker Fas was down-regulated on germinal centre B cells from TLR4-KO mice. Likewise, decreased expression of inducible costimulator on follicular T helper cells was observed in immunized TLR4-KO mice. Moreover, a potent protective antigen-specific humoral immune response was mimicked using an adjuvant system containing the TLR4 agonist monophosphoryl lipid A. Overall, our findings showed that very rapid antigen-specific antibody production is correlated with the TLR4-imprinted germinal centre response to AdV-based vaccine. These results provide additional evidence for the use of the AdV and a TLR agonist to induce humoral responses. Our findings offer new insights into rational vaccine design.

A comprehensive proteogenomic study of the human Brucella vaccine strain 104 M.

BACKGROUND: Brucella spp. are Gram-negative, facultative intracellular pathogens that cause brucellosis in both humans and animals. The B. abortus vaccine strain 104 M is the only vaccine available in China for the prevention of brucellosis in humans. Although the B. abortus 104 M genome has been fully sequenced, the current genome annotations are not yet complete. In addition, the main mechanisms underpinning its residual toxicity and vaccine-induced immune protection have yet to be elucidated. Mapping the proteome of B. abortus 104 M will help to improve genome annotation quality, thereby facilitating a greater understanding of its biology. RESULTS: In this study, we utilized a proteogenomic approach that combined subcellular fractionation and peptide fractionation to perform a whole-proteome analysis and genome reannotation of B. abortus 104 M using high-resolution mass spectrometry. In total, 1,729 proteins (56.3% of 3,072) including 218 hypothetical proteins were identified using the culture conditions that were employed this study. The annotations of the B. abortus 104 M genome were also refined following identification and validation by reverse transcription-PCR. In addition, 14 pivotal virulence factors and 17 known protective antigens known to be involved in residual toxicity and immune protection were confirmed at the protein level following induction by the 104 M vaccine. Moreover, a further insight into the cell biology of multichromosomal bacteria was obtained following the elucidation of differences in protein expression levels between the small and large chromosomes. CONCLUSIONS: The work presented in this report used a proteogenomic approach to perform whole-proteome analysis and genome reannotation in B. abortus 104 M; this work helped to improve genome annotation quality. Our analysis of virulence factors, protective antigens and other protein effectors provided the basis for further research to elucidate the mechanisms of residual toxicity and immune protection induced by the 104 M vaccine. Finally, the potential link between replication dynamics, gene function, and protein expression levels in this multichromosomal bacterium was detailed.

The zero ischemia index (ZII): a novel criterion for predicting complexity and outcomes of off-clamp partial nephrectomy.

PURPOSES: Although several anatomical classification systems that aimed to standardize the description of renal tumors were previously reported, a special classification system is required to help predict the complexity and perioperative outcomes of off-clamp nephron-sparing surgery (NSS). We developed a novel criterion-zero ischemia index (ZII), aiming to help predict the perioperative outcomes after off-clamp NSS and guide patient selection. METHODS: We retrospectively evaluated 149 patients between June 2009 and July 2014 in our institution who underwent off-clamp NSS with available computed tomography images. ZII was defined as the product of the tumor diameter and depth within renal parenchyma. ZII was then analyzed to investigate its association with perioperative outcomes. A specific ZII score was further selected to best guide patient selection in off-clamp NSS. RESULTS: ZII was significantly associated with estimated blood loss >500 mL (OR 1.270, 95% CI 1.036-1.557, p = 0.021), operative time >2 h (OR 1.286, 95% CI 1.051-1.573, p = 0.014), surgical complications (OR 1.251, 95% CI 1.035-1.511, p = 0.020), overall complications (OR 1.208, 95% CI 1.016-1.436, p = 0.032), and >10% decrease in estimated glomerular filtration rate (OR 1.362, 95% CI 1.045-1.776, p = 0.022). Patients with ZII > 6 may bear a higher risk of hemorrhage, perioperative complications, and a longer operative time, if they underwent an off-clamp NSS, compared to those with ZII ≤ 6. CONCLUSIONS: The ZII is a novel and readily measurable criterion which can help predict renal complexity of tumor and risk of perioperative outcomes after off-clamp NSS. ZII = 6 is established as a preliminary threshold for patient selection of off-clamp NSS. A more robust criterion is to be validated with more samples in a prospective study.

An optimized transurethral catheterization cystometry in mice and comparison with classic suprapubic catheterization cystometry.

AIMS: The aim of this study is to establish an optimized, minimally invasive transurethral catheterization cystometry (TUCC) and a novel urethral pressure profile (UPP) measurement for mice. METHODS: The optimized TUCC and the UPP measurement were first established. This optimized TUCC was then performed in 16 anesthetized female mice and compared with the suprapubic catheterization cystometry (SCC) in parallel after suprapubic catheters implantation (SCI; on zero, third, and seventh day, respectively). Finally, the optimized TUCC and novel UPP measurement were applied to investigate in another eight mice of partial bladder outlet obstruction (pBOO) model. The urodynamic parameters including micturition pressure (MP), basal pressure (BP), threshold pressure (TP), bladder capacity (BC), micturition volume (MV), residual urine (RV), bladder compliance (COM), maximum urethral pressure (MUP), bladder pressure curve and UPP were recorded. Statistical cross-comparisons of parameters for two kinds of cystometries and pBOO model were performed. RESULTS: Compared with the optimized TUCC before SCI, the MV, RV, BC, and MP decreased significantly on the seventh day after SCI (270.4-132.5 µL, 46.13-20.09 µL, 316.4-152.5 µL, 30.01-24.34 cmH2 0, respectively). After SCI, the BP, MP, TP, MV, RV, BC, and COM showed no significant difference between the TUCC and SCC at the same time point. The MUP increased significantly after pBOO operation (19.1-46.6 cmH2 0, P < 0.05). CONCLUSIONS: The minimally invasive TUCC along with UPP measurement could be widely applied to study the bladder function of mice as a feasible, repeatable, and accessible method.

In situ expression of (R)-carbonyl reductase rebalancing an asymmetric pathway improves stereoconversion efficiency of racemic mixture to (S)-phenyl-1,2-ethanediol in Candida parapsilosis CCTCC M203011.

BACKGROUND: Candida parapsilosis (R)-carbonyl reductase (RCR) and (S)-carbonyl reductase (SCR) are involved in the stereoconversion of racemic (R,S)-1-phenyl-1,2-ethanediol (PED) to its (S)-isomer. RCR catalyzes (R)-PED to 2-hydroxyacetophenone (2-HAP), and SCR catalyzes 2-HAP to (S)-PED. However, the stereoconversion efficiency of racemic mixture to (S)-PED is not high because of an activity imbalance between RCR and SCR, with RCR performing at a lower rate than SCR. To realize the efficient preparation of racemic mixture to (S)-PED, an in situ expression of RCR and a two-stage control strategy were introduced to rebalance the RCR- and SCR-mediated pathways. RESULTS: An in situ expression plasmid pCP was designed and RCR was successfully expressed in C. parapsilosis. With respect to wild-type, recombinant C. parapsilosis/pCP-RCR exhibited over four-fold higher activity for catalyzing racemic (R,S)-PED to 2-HAP, while maintained the activity for catalyzing 2-HAP to (S)-PED. The ratio of k cat /K M for SCR catalyzing (R)-PED and RCR catalyzing 2-HAP was about 1.0, showing the good balance between the functions of SCR and RCR. Based on pH and temperature preferences of RCR and SCR, a two-stage control strategy was devised, where pH and temperature were initially set at 5.0 and 30 °C for RCR rapidly catalyzing racemic PED to 2-HAP, and then adjusted to 4.5 and 35 °C for SCR transforming 2-HAP to (S)-PED. Using these strategies, the recombinant C. parapsilosis/pCP-RCR catalyzed racemic PED to its (S)-isomer with an optical purity of 98.8 % and a yield of 48.4 %. Most notably, the biotransformation duration was reduced from 48 to 13 h. CONCLUSIONS: We established an in situ expression system for RCR in C. parapsilosis to rebalance the functions between RCR and SCR. Then we designed a two-stage control strategy based on pH and temperature preferences of RCR and SCR, better rebalancing RCR and SCR-mediated chiral biosynthesis pathways. This work demonstrates a method to improve chiral biosyntheses via in situ expression of rate-limiting enzyme and a multi-stage control strategy to rebalance asymmetric pathways.

[Efficient biosynthesis of (S)-1-phenyl-1,2-ethanediol catalyzed by (S)-carbonyl reductase â ¡ and glucose dehydrogenase].

Objective: To realize efficient biosynthesis of 2-hydroxyacetophenone to (S)-1-phenyl-1,2-ethanediol, we designed a co-expression system containing Candida parapsilosis CCTCC M203011 (S)-carbonyl reductase Ⅱ (SCRⅡ) and Bacillus sp. YX-1 glucose dehydrogenase (GDH) in Escherichia coli BL21(DE3), based on the optimal ratio between the specific activities of the two enzymes. Methods: The enzymes SCRⅡ and GDH were purified from their corresponding recombinant E. coli strains. When the purified SCRⅡ and GDH were used for the reduction of 2-hydroxyacetophenone to (S)-1-phenyl-1,2-ethanediol, the optimal ratio between their specific activities, the optimal temperature and pH were determined. Based on above results, a co-expression system E. coli BL21(DE3)/S-SD-AS-G harboring SCRⅡ and GDH was constructed. Results: SCRⅡ and GDH exhibited specific activities of 1.3 U/mg and 13.5 U/mg. When the total enzyme activity was 1 U, the optimal ratio of their activities is between 1:1 and 5:1, and the optimal temperature and pH are 30℃ and 7.0, respectively. So we designed a co-expression system E. coli BL21/S-SD-AS-G, in which the ratio of the SCRⅡ and GDH genes is 1:1. The specific activities of SCRⅡ and GDH are 0.76 U/mg and 0.73 U/mg in the cell-free extracts of E. coli BL21(DE3)/S-SD-AS-G, respectively. The ratio between SCRⅡ and GDH activity is 1:1. Under the optimal conditions, the system showed excellent performance to produce (S)-1-phenyl-1,2-ethanediol with an optical purity and a yield both over 99% during the reduction of 2-hydroxyacetophenone. With respect to the recombinant E. coli BL21(DE3)/pET-SCRⅡ, the co-expression system obviously improved the yield of (S)-1-phenyl-1,2-ethanediol and reduced biotransformation time from 24 h to 13 h. Conclusion: This work provides the research foundation on the construction of a co-expression system containing a target chiral catalyst and a cofactor-regeneration enzyme for efficient chiral biosynthesis based on the optimal ratio of SCRⅡ and GDH activities.

[Expression and functions of (S)-carbonyl reductase II in Saccharomyces cerevisiaes spores].

OBJECTIVE: To realize efficient biotransformation of (S)-1-phenyl-1,2-ethanediol by recombinant (S)-carbonyl reductase II, we expressed (S)- carbonyl reductase II from Candida parapsilosis CCTCC M203011 and embedded it in the spores of Saccharomyces cerevisiae AN120. METHODS: (S)-carbonyl reductase II gene was cloned from C. parapsilosis genome and expressed in S. cerevisiae AN120 by PCR amplification. When cultured with potassium acetate as the sole carbon source, the yeast spores were produced, and embedded the recombinant (S)-carbonyl reductase II. Using 10% W/V spores as biocatalysts, 6 g/L 2-hydroxyacetophenone as substrate, the biotransformation was carried out and the optical purity and yield of products were analyzed by HPLC. During the biotransformation of 2-hydroxyacetophenone to (S)-1-phenyl-1,2-ethanediol, the optimal temperature and pH, stability and reusability of the recombinant spores were determined. RESULTS: The recombinant yeast spores showed excellent performance to give (S)-1-phenyl-1,2- ethanediol with a high optical purity of 99.3% and a high yield of 99.0% at the optimal temperature (40 °C) and pH (6.0). Compared with the recombinant Escherichia coli, the spores improved the yield of (S)-1-phenyl-1,2-ethanediol from 89.7% to 99.0%, and shortened the biotransformation duration from 48 h to 4 h. After being reused for 10 times, the recombinant spores biotransformed (S)-1-phenyl-1,2-ethanediol with a stable optical purity of about 99% and a yield over 85%. CONCLUSION: The heterologous expression of oxidoreductases was first realized in yeast spores, which laid a solid foundation for efficient preparation of chiral compounds.

Gender difference in association of NEDD4L gene variants among southern Han Chinese with essential hypertension - a population-based case-control study.

Genetic variation of NEDD4L has been associated with hypertension and related phenotypes with conflicting results, probably attributable to gender-, age- and ethnicity-related variations in its phenotypic expression. We evaluated the association of three representative polymorphisms in NEDD4L (rs2288774, rs3865418 and rs4149601) with essential hypertension (EH) in a community-based sample of men (n = 1029) and women (n = 869) belonging to Han Chinese, Southern China, to probe whether gender interacts with NEDD4L in contributing to the risk of EH. In this population sample, rs4149601 was excluded from further analysis due to deviation from Hardy-Weinberg equilibrium. For two other variants tested, the allele frequencies and genotype distributions did not differ between cases and controls (p > 0.05) when both genders were combined. However, sex-stratified analysis revealed that the distribution of the dominant model of rs2288774 (TC + CC versus TT) and the additive and dominant (CT + TT versus CC) models of rs3865418 differed significantly between cases and controls in men (p = 0.044, 0.041 and 0.016, respectively) but not in women. After adjusting for confounding factors, logistic regression analysis showed that rs2288774 and rs3865418 (in the dominant model) were still significantly associated with EH (rs2288774: OR = 0.73, 95% CI = 0.57-0.95, p = 0.017 and rs3865418: OR = 0.71, 95% CI = 0.55-0.92, p = 0.009) in men. There was a significant interaction between the NEDD4L genotype and gender (p for interaction: 0.046 for rs2288774 and 0.033 for rs3865418). Genetic variation in NEDD4L may have sex-dependent effects in the development of EH in Han Chinese. Previous studies that ignore gender-specific effects in their design and interpretation could have failed to identify a uniform conclusion.

Prevalence of noncommunicable diseases and their risk factors in Guangzhou, China.

INTRODUCTION: This article reports on the prevalence of noncommunicable diseases (NCDs) and their risk factors in the city of Guangzhou, China, and shows a trend toward epidemic proportions when municipal data are compared with provincial data. METHODS: We conducted the Guangzhou Community Health Survey in the 12 administrative districts of Guangzhou to learn about NCDs and their risk factors. A community-based, face-to-face survey with a stratified multistage cluster sampling was used. Information was gathered on 27,743 respondents, aged 0 to 108 years, with a male to female ratio of 1 to 1. All participants completed a questionnaire, and those aged 15 years or older had a physical examination. Survey results were compared with the provincial results of the 2002 Guangdong Nutrition and Health Survey (GNHS). RESULTS: The data were weighted to the respondent's probability of selection and to the age- and sex-specific population. Prevalence estimate of self-reported NCDs was 16.0%. Hypertension and diabetes were reported as the most important NCDs. Of those who responded, 6.8% reported having more than 2 chronic conditions. The adjusted prevalence of hypertension decreased by 13.3% since 2002. Awareness, treatment, and control of hypertension and diabetes were improved. The estimated prevalence of current smoking decreased, and the prevalence of former smoking increased from 2002. However, the prevalence of overweight and obesity, especially central obesity, increased. CONCLUSION: Results were encouraging with regard to hypertension and diabetes. However, the unfavorable trends, especially for overweight, central obesity, and passive smoking, call for additional action.

Ultrasound-based Radiomics Predicts Short-term Outcomes in Hepatitis B Virus-related Acute-on-chronic Liver Failure.

BACKGROUND: The prognosis in hepatitis B virus-associated acute-on-chronic liver failure (HBV-ACLF) is challenging due to heterogeneity. Radiomics may enable noninvasive outcome prediction. OBJECTIVE: This study aimed to evaluate ultrasound-based radiomics for predicting outcomes in HBV-ACLF. METHODS: We enrolled 264 HBV-ACLF patients, dividing them into a training cohort (n=184) and a validation cohort (n=80). From hepatic ultrasound images, 455 radiomic features were extracted. Radiomics-based phenotypes were identified through unsupervised hierarchical clustering. A radiomic signature was developed using a Cox-LASSO algorithm to predict 30-day mortality. Furthermore, we integrated the signature with independent clinical predictors via multivariate Cox regression to construct a combined clinical-radiomic nomogram (CCR-nomogram). Integrated discrimination improvement (IDI) and net reclassification improvement (NRI) assessed performance improvements achieved by adding radiomic features to clinical data. RESULTS: Both clustering and radiomic signature identified two distinct subgroups with significant differences in clinical characteristics and 30-day prognosis. In the training cohort, the signature achieved a C-index of 0.746, replicated in validation with a C-index of 0.747. The CCR-nomogram achieved C-indices of 0.834 and 0.819 for the training and validation cohorts. Incorporating radiomic features significantly improved the CCRnomogram over the signature and clinical-only models, evidenced by IDI of 0.108-0.264 and NRI of 0.292-0.540 in both cohorts (all p0.05). CONCLUSION: Ultrasound-based radiomics offered prognostic information complementary to clinical data and demonstrated potential to enhance outcome prediction in HBV-ACLF.