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Background: We aimed to develop and validate a new nomogram for predicting the risk of intracranial hemorrhage (ICH) in patients with acute ischemic stroke (AIS) after intravenous thrombolysis (IVT). Methods: A retrospective study enrolled 553 patients with AIS treated with IVT. The patients were randomly divided into two cohorts: the training set (70%, n = 387) and the testing set (30%, n = 166). The factors in the predictive nomogram were filtered using multivariable logistic regression analysis. The performance of the nomogram was assessed based on the area under the receiver operating characteristic curve (AUC-ROC), calibration plots, and decision curve analysis (DCA). Results: After multivariable logistic regression analysis, certain factors, such as smoking, National Institutes of Health of Stroke Scale (NIHSS) score, blood urea nitrogen-to-creatinine ratio (BUN/Cr), and neutrophil-to-lymphocyte ratio (NLR), were found to be independent predictors of ICH and were used to construct a nomogram. The AUC-ROC values of the nomogram were 0.887 (95% CI: 0.842–0.933) and 0.776 (95% CI: 0.681–0.872) in the training and testing sets, respectively. The AUC-ROC of the nomogram was higher than that of the Multicenter Stroke Survey (MSS), Glucose, Race, Age, Sex, Systolic blood Pressure, and Severity of stroke (GRASPS), and stroke prognostication using age and NIH Stroke Scale-100 positive index (SPAN-100) scores for predicting ICH in both the training and testing sets (p < 0.05). The calibration plot demonstrated good agreement in both the training and testing sets. DCA indicated that the nomogram was clinically useful. Conclusions: The new nomogram, which included smoking, NIHSS, BUN/Cr, and NLR as variables, had the potential for predicting the risk of ICH in patients with AIS after IVT. [ABSTRACT FROM AUTHOR]

The chemokine receptor CXCR4 functions as a fusion coreceptor for T cell tropic and dual-tropic HIV-1 strains. To identify regions of CXCR4 that are important for coreceptor function, CXCR4-CXCR2 receptor chimeras were tested for the ability to support HIV-1 envelope (env) protein-mediated membrane fusion. Receptor chimeras containing the first and second extracellular loops of CXCR4 supported fusion by T tropic and dual-tropic HIV-1 and HIV-2 strains and binding of a monoclonal antibody to CXCR4, 12G5, that blocks CXCR4-dependent infection by some virus strains. The second extracellular loop of CXCR4 was sufficient to confer coreceptor function to CXCR2 for most virus strains tested but did not support binding of 12G5. Truncation of the CXCR4 cytoplasmic tail or mutation of a conserved DRY motif in the second intracellular loop did not affect coreceptor function, indicating that phosphorylation of the cytoplasmic tail and the DRY motif are not required for coreceptor function. The results implicate the involvement of multiple CXCR4 domains in HIV-1 coreceptor function, especially the second extracellular loop, though the structural requirements for coreceptor function were somewhat variable for different env proteins. Finally, a hybrid receptor in which the amino terminus of CXCR4 was replaced by that of CCR5 was active as a coreceptor for M tropic, T tropic, and dual-tropic env proteins. We propose that dual tropism may evolve in CCR5-restricted HIV-1 strains through acquisition of the ability to utilize the first and second extracellular loops of CXCR4 while retaining the ability to interact with the CCR5 amino-terminal domain.

Two new compounds, (7R, 2E, 5E)-3,5,7-trimethyl-2,5-octadienedioic-8-methyl ester (1) and neovasipyridone G (3), together with a new natural product compound (7R,2E,5E)-3,5,7-trimethyl-2,5-octadienedioic acid (2), and six known compounds (4–9) were isolated from Penicillium sp. SYPF7381. Their structures were elucidated on the basis of extensive spectroscopic analysis, and the absolute configurations of compounds 1 and 2 were determined by optical rotation. The absolute configuration of compound 3 was determined by means of electronic circular dichroism (ECD) calculation. In addition, the in vitro anti-inflammatory activities of all compounds were assayed in RAW 264.7 cells by assessing LPS-induced NO production. Furthermore, the structure-antiinflammation activity relationships for these isolated compounds were summarized based on the experimental as well as the docking results. [ABSTRACT FROM AUTHOR]

(+) Benzomalvins E (1) and (-) Benzomalvins E (2), a pair of epimeric derivatives, together with three known benzomalvins (3–5), were isolated from solid cultures of a interrhizospheric fungus Penicillium sp. SYPF 8411. The planar structure of (+) Benzomalvins E (1) has been previously reported. While, the absolute configuration of compound 1 was established by X-ray crystallographic analysis for the first time. The planar structure of the new compound 2 were elucidated by detailed interpretation of their HR ESI-TOF MS and NMR spectroscopic data. The absolute configuration of compound 2 was established by Rh2(OCOCF3)4-induced CD spectral data and the electronic circular dichroic (ECD) method. Furthermore, the epimerization induced by pH, temperature and H2O was revealed. Benzomalvins (1–3, 5), a type of indoximod, enhanced the cytotoxic capability of 5-fluorouracil against A549. [ABSTRACT FROM AUTHOR]

One new indole diterpenoid, drechmerin I (1), was isolated from the fermentation broth of Drechmeria sp. isolated from the root of Panax notoginseng. Its structure was elucidated based on 1 D and 2 D nuclear magnetic resonance (NMR), high resolution electrospray ionization mass spectrum (HRESIMS), and electronic circular dichroism (ECD) spectroscopic analyses as well as TD DFT calculations of ECD spectra. Drechmerin I (1) was assayed for its antimicrobial activity against Candida albicans, Staphylococcus aureus, Bacillus cereus, B. subtillis, Pseudomonas aeruginosa, and Klebsiella pneumonia, respectively. Drechmerin I (1) showed antimicrobial activities against B. subtillis with an MIC value of 200 μg/mL. The interaction of S. aureus peptide deformylase with drechmerin I (1) was investigated by molecular docking. [ABSTRACT FROM AUTHOR]

Highlights • BIT could seriously inhibit microalgal growth by damaging the photosynthetic system. • Microalgae could recover from the inhibition if BIT concentration was not high. • BIT consumption was the primary reason for algal growth recovery. • Microalgae were still alive even if their growth was completely inhibited. • SOD, CAT and GSH played a key role in algal detoxification against BIT poisoning. Abstract Isothiazolinones, such as 1,2-benzisothiazol-3(2H)-one (BIT), are widely used as biocides for bacterial growth control in many domestic and industrial processes. Despite their advantages as biocides, they are highly toxic and pose a potential risk to the environment. This study investigated the inhibition process and detoxification mechanism involved in microalgal survival and growth recovery after BIT poisoning. BIT could seriously inhibit the growth of Scenedesmus sp. LX1, Chlorella sp. HQ, and Chlamydomonas reinhardtii with half maximal effective concentrations at 72 h (72h-EC 50) of 1.70, 0.41, and 1.16 mg/L, respectively. The primary inhibition mechanism was the BIT-induced damage to microalgal photosynthetic systems. However, the inhibited strains could recover when their growth was not completely inhibited. The influence of this inhibiting effect on subsequent algal regrowth was negligible or weak. BIT consumption was the primary reason for their recovery. Notably, algae did not die even if their growth was completely inhibited. If the BIT concentration did not exceed a certain high level, then the inhibited algae could recover their growth relatively well. Microalgal generation of reduced glutathione (GSH) and the oxygen radical scavenging enzymes, superoxide dismutase (SOD) and catalase (CAT), played a key role in detoxification against BIT poisoning. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Rare ginsenosides were successfully bio-transformed by Aspergillus tubingensis. • Rh4 aglycone increased over 100 folds than that in the original TSSLG. • MCL-1 was explored as anticancer target of Rh4 and its aglycone. Abstract Rare ginsenoside Rh 4 and its aglycone are present in low levels in Panax ginseng. This study focused on achieving ginsenoside Rh 4 and its aglycone by microbial transformation of the total saponins of stems and leaves of P. ginseng (TSSLG). A total of 78 fungal strains isolated from the rhizosphere soil of P. ginseng , and one of them, Aspergillus tubingensis , was found to be capable of biotransformation of TSSLG to ginsenoside Rh4 and its aglycone with high efficiency, especially the content of ginsenoside Rh4 aglycone was enhanced 100 folds over than that in the original TSSLG. Compared with ginsenoside Rg3 (named ShenYi capsule as antitumor drug in China), ginsenoside Rh4 aglycone exhibited stronger antitumor activity against human cancer cell lines SGC-7901, KB-A-1 and HT-1080. The possible biotransformation pathways of ginsenoside Rh4 and its aglycone were speculated according to the chemical structures. The anticancer binding-target, myeloid cell leukemia 1 protein (MCL-1), was explored using molecular docking analysis and the possible combination mechanism was discussed. [ABSTRACT FROM AUTHOR]

Methylisothiazolinone (MIT) has been widely used to control bacterial growth in reverse osmosis (RO) systems. However, MIT's toxicity on microalgae should be determined because residual MIT is concentrated into RO concentrate (ROC) and might have a severe impact on microalgae-based ROC treatment. This study investigated the tolerance of Scenedesmus sp. LX1 to MIT and revealed the mechanism of algal growth inhibition and toxicity resistance. Scenedesmus sp. LX1 was inhibited by MIT with a half-maximal effective concentration at 72 h (72 h-EC 50 ) of 1.00 mg/L, but the strain recovered from the inhibition when its growth was not completely inhibited. It was observed that this inhibition's effect on subsequent growth was weak, and the removal of MIT was the primary reason for the recovery. Properly increasing the initial algal density significantly shortened the adaptation time for accelerated recovery in a MIT-containing culture. Photosynthesis damage by MIT was one of the primary reasons for growth inhibition, but microalgal cell respiration and adenosine triphosphate (ATP) synthesis were not completely inhibited, and the algae were still alive even when growth was completely inhibited, which was notably different from observations made with bacteria and fungi. The algae synthesized more chlorophyll, antioxidant enzymes of superoxide dismutase (SOD) and catalase (CAT), and small molecules, such as reduced glutathione (GSH), to resist MIT poisoning. The microalgae-based process could treat the MIT-containing ROC, since MIT was added for only several hours a week in municipal wastewater reclamation RO processes, and the MIT average concentration was considerably lower than the maximum concentration that algae could tolerate. [ABSTRACT FROM AUTHOR]

A total of 58 fungal isolates, belonging to 24 genera, were obtained from the leaves, stems and roots of Ginkgo biloba L.. Among them, one endophytic fungal strain, Penicillium cataractum SYPF 7131, displayed the strongest antibacterial activity. Four new compounds ( 1 – 4) were isolated from the strain fermentation broth together with four known compounds ( 5 – 8) . These structures were determined on the basis of 1D and 2D NMR and [Rh 2 (OCOCF 3 ) 4 ]-induced electronic circular dichroism (ECD) spectroscopic analyses. All the isolated compounds were screened for their in vitro antimicrobial activities. Compound 3 and 4 showed moderate inhibitory activity against Staphylococcus aureus . Compound 7 exhibited significant inhibitory activity against S. aureus with MIC value of 10 μg/mL. Further, the in silico molecular docking studies of the active compounds was used to explore the binding interactions with the active site of filamentous temperature-sensitive protein Z (FtsZ) from Staphylococcus aureus . The docking results revealed that compounds 3 , 4 and 7 showed high binding energies, strong H-bond interactions and hydrophobic interactions with FtsZ from S. aureus validating the observed antimicrobial activity. Based on antimicrobial activities and docking studies, compounds 3 , 4 and 7 were identified as promising antimicrobial lead molecules. [ABSTRACT FROM AUTHOR]

In many microalgal cultivation systems, microalgae co-exist with bacteria, while little is known about the characteristics of their symbiotic relationships. In this study, twenty-six microalgae growth-promoting bacteria were isolated from a culture system of Scenedesmus sp. LX1 cultivated in the secondary effluent from domestic wastewater by using the high-throughput multiple well plate screening method. Ten strains were found to produce and secrete indole acetic acid (IAA), promoting the growth of microalgae. Meanwhile, the microalgae might have secreted signal substances to induce IAA production in bacteria, which was amplified in the tryptophan abundant environment. This indicates that bacteria may mainly promote the growth of the co-existing microalgae through secreting IAA, and microalgae would selectively enhance IAA secretion in turn. Microalgae cultured with microalgal growth-promoting bacteria would be a new potential strategy for improving large-scale microalgal cultivation in an economic and environmentally-friendly way. [ABSTRACT FROM AUTHOR]

Microalgae cultivation is a promising candidate for autotrophic sequestrating CO 2 transformation into renewable bio-products. However, potential of microalgae has not been fully explored due to the bottlenecks of biomass harvesting during large-scale microalgae cultivation. A novel capillary-driven photobioreactor (CPBR) is proposed in this study for attached microalgae cultivation obtaining high biomass productivity and overcoming the biomass harvesting limitation in traditional suspended cultures. Performances on microalgal growth, cellular composition, nutrients uptake from water, and corresponding light utilization efficiencies were investigated and emphasized. During 12 days of system operation, attached microalgal biomass on the carriers were in the range of 83.6 g/m 2 -footprint area of 121.5 g/m 2 -footprint area, corresponding to light utilization efficiency of 3.3% to 4.8%. With proper carriers packing density of 16% to 32%, obtained biomass productivities of CPBR were approximately 10 g/m 2 /d (footprint area). Biomass composition analysis revealed that lipid and carbohydrates contents in attached microalgal biomass were higher than in suspended microalgal biomass with same cultivating conditions, proving the potential of microalgae cultivated in CPBR as feedstock of biofuels. [ABSTRACT FROM AUTHOR]

Reuse of secondary municipal effluent from wastewater treatment plants in water bodies could effectively alleviate freshwater resource shortage. However, excessive nutrients must be efficiently removed to prevent eutrophication. Compared with other means of advanced wastewater treatment, microalgae-based processes display overwhelming advantages including efficient and simultaneous N and P removal, no requirement of additional chemicals, O generation, CO mitigation, and potential value-added products from harvested biomass. One particular challenge of microalgae-based advanced municipal wastewater treatment compared to treatment of other types of wastewater is that concentrations of nutrients and N:P ratios in secondary municipal effluent are much lower and imbalanced. Therefore, there should be comprehensive considerations on nutrient removal from this specific type of effluent. Removal of nutrients and organic substances, and other environmental benefits of microalgae-based advanced municipal wastewater treatment systems were summarized. Among the existing studies on microalgal advanced nutrient removal, much information on major parameters is absent, rendering performances between studies not really comparable. Mechanisms of microalgae-based nitrogen and phosphorus removal were respectively analyzed to better understand advanced nutrient removal from municipal secondary effluent. Factors influencing microalgae-based nutrient removal were divided into intrinsic, environmental, and operational categories; several factors were identified in each category, and their influences on microalgal nutrient removal were discussed. A multiplicative kinetic model was integrated to estimate microalgal growth-related nutrient removal based majorly on environmental and intrinsic factors. Limitations and prospects of future full-scale microalgae-based advanced municipal wastewater treatment were also suggested. The manuscript could offer much valuable information for future studies on microalgae-based advanced wastewater treatment and water reuse. [ABSTRACT FROM AUTHOR]

Objective Chlamydia psittaci is an avian respiratory pathogen and zoonotic agent. The wide prevalence of C. psittaci poses a threat to the poultry industry and its employees. However, few commercial kits are available for detecting avian antibodies excluding the in-house ELISA kit. In this study, we developed a novel ELISA kit for detecting antibodies against C. psittaci based on the N-terminal fragment of polymorphic outer membrane protein D (PmpD-N) as the coating antigen. Methods The antigen concentrations, primary antibody, and cut-off value were determined and optimized. The ELISA, designated PmpD-N ELISA, was assessed for sensitivity, specificity, and concordance using sera samples from 48 experimentally infected and 168 uninfected SPF chickens. Results The sensitivity and specificity of PmpD-N ELISA were 97.9%, 100%, respectively, while the concordance was 98.1% as compared to that of MOMP-ELISA. No cross-reaction with positive sera for other avian pathogens was found. Using PmpD-N ELISA, 799/836 clinical samples were positive, including 93.0% and 98.1% positivity in layers and broilers, respectively. Conclusion These data indicate that indirect ELISA with PmpD-N as the antigen candidate is a promising approach for the surveillance of C. psittaci infection. [ABSTRACT FROM AUTHOR]