PCSK9 induces endothelial cell autophagy by regulating the PI3K/ATK pathway in atherosclerotic coronary heart disease.

OBJECTIVE: Atherosclerosis is a chronic inflammatory disease of the arteries, and its pathogenesis is related to endothelial dysfunction. It has been found that the protein convertase subtilin/kexin9 type (PCSK9) plays an important role in AS, but its specific mechanism is still unclear. METHODS: In this study, we first cultured human umbilical vein endothelial cells (HUVECs) with 50 or 100µg/ml oxidized low-density lipoprotein (ox-LDL) for 24 hours to establish a coronary atherosclerosis cell model. RESULTS: The results showed that ox-LDL induced HUVEC injury and autophagy and upregulated PCSK9 protein expression in HUVECs in a concentration-dependent manner. Silencing PCSK9 expression with siRNA inhibited ox-LDL-induced HUVEC endothelial dysfunction, inhibited the release of inflammatory factors, promoted HUVEC proliferation and inhibited apoptosis. In addition, ox-LDL increased the expression of LC3B-I and LC3B-II and decreased the expression of p62. However, these processes are reversed by sh-PCSK9. In addition, sh-PCSK9 can inhibit PI3K, AKT and mTOR phosphorylation and promote autophagy. CONCLUSION: Taken together, our research shows that silencing PCSK9 inhibits the PI3K/ATK/mTOR pathway to activate ox-LDL-induced autophagy in vascular endothelial cells, alleviating endothelial cell injury and inflammation.

Relationship of neutrophil/lymphocyte ratio with cerebral small vessel disease and its common imaging markers.

BACKGROUND: High neutrophil/lymphocyte ratio (NLR) is associated with poor prognosis in ischemic stroke. However, the role of NLR in cerebral small vessel disease (CSVD) is controversial. Herein, we evaluated the value of NLR in identifying CSVD and its relationship with the common imaging markers of CSVD. METHODS: A total of 667 patients were enrolled in this study, including 368 in the CSVD group and 299 in the non-CSVD group. Clinical, laboratory, and imaging data were collected. The relationship of NLR with CSVD and common imaging markers of CSVD were analyzed with univariate and multivariate logistic regression analysis. The predictive value of NLR was assessed with the receiver operating characteristic curve. RESULTS: NLR (odds ratio [OR] = 1.929, 95% confidence interval [CI] = 1.599-2.327, p < .001) was an independent risk factor for CSVD. NLR was also independently associated with moderate to severe white matter hyperintensity (WMH) (OR = 2.136, 95% CI = 1.768-2.580, p < .001), moderate to severe periventricular WMH (OR = 2.138, 95% CI = 1.771-2.579, p < .001), and moderate to severe deep WMH (OR = 1.654, 95% CI = 1.438-1.902, p < .001), moderately to severely enlarged perivascular spaces (EPVS) (OR = 1.248, 95% CI = 1.110-1.402, p < .001), moderately to severely EPVS in the basal ganglia (OR = 1.136, 95% CI = 1.012-1.275, p = .030), and moderately to severely EPVS in the centrum semiovale (OR = 1.140, 95% CI = 1.027-1.266, p = .014). However, NLR was not statistically significantly associated with lacune. The optimal cutoff point of NLR in predicting CSVD was 2.47, with sensitivity and specificity of 84.2% and 66.9%, respectively (p < .01). The diagnostic effect was maximized when NLR was combined with other risk factors. CONCLUSIONS: NLR is an independent risk factor for CSVD and is independently associated with common imaging markers of CSVD. NLR may serve as a valid and convenient biomarker for assessing CSVD.

The perilous consequences of bowel preparation: a case study with literature review of Boerhaave syndrome.

Colonoscopy is widely acknowledged as a prevalent and efficacious approach for the diagnosis and treatment of gastrointestinal disorders. In order to guarantee an effective colonoscopy, it is imperative for patients to undergo an optimal bowel preparation regimen. This entails the consumption of a substantial volume of a non-absorbable solution to comprehensively purge the colon of any fecal residue. Nevertheless, it is noteworthy to acknowledge that the bowel preparation procedure may occasionally elicit adverse symptoms such as nausea and vomiting. In exceptional instances, the occurrence of excessive vomiting may lead to the rupture of the distal esophagus, a grave medical condition referred to as Boerhaave syndrome (BS). Timely identification and efficient intervention are imperative for the management of this infrequent yet potentially perilous ailment. This investigation presents a case study of a patient who developed BS subsequent to the ingestion of mannitol during bowel preparation. Furthermore, an exhaustive examination of extant case reports and pertinent literature on esophageal perforation linked to colonoscopy has been conducted. This analysis provides valuable insights into the prevention, reduction, and treatment of such serious complications.

Improvement of mild photoaged facial skin in middle-aged Chinese females by a supramolecular retinol plus acetyl hexapeptide-1 containing essence.

Background: The anti-ageing gold standard, retinol, has been widely recognized for its anti-wrinkle benefits in the Chinese population. Studies have shown that Asians are more sensitive to retinol compared to their Caucasian counterparts, and it is generally recommended to use retinol once a day in the evening. However, there are few reports on the most appropriate concentration and frequency of retinol use in the general Chinese population. Objectives: In this study, supramolecular retinol was prepared using cyclodextrin encapsulation technology, and the most appropriate concentration for the general Chinese population was investigated. Then, a cosmetic essence was developed by combining the classic supramolecular retinol, which promotes collagen regeneration, with acetyl hexapeptide-1, a popular ingredient known for reducing expression lines. The safety and efficacy of this cosmetic essence were studied through clinical tests. Methods: First, a patch test was conducted on 32 healthy Chinese subjects to compare the tolerance of supramolecular retinol to non-encapsulated retinol and to select the optimal concentration of retinol. Then, an 8-week clinical study was conducted using a twice-daily cosmetic essence containing 0.1% supramolecular retinol and 0.02% acetyl hexapeptide-1 to treat mild photoaging in 32 middle-aged Chinese women. Dermatological evaluations and instrument measurements were taken at baseline, 4 weeks, and 8 weeks. Efficacy was assessed using facial skin wrinkles, textures, elasticity, firmness, pores, gloss and stratum corneum hydration. Tolerability was assessed throughout the study. Results: Our patch test results showed that supramolecular retinol was better tolerated than non-encapsulated retinol, and our findings suggest that 0.1% was the approximate optimal retinol concentration for the general Chinese population. The cosmetic essence studied was effective in improving the appearance of photoaged skin in the Chinese population in all aspects studied and was well tolerated. Conclusions: 0.1% retinol is suitable for twice daily use in the general Chinese population. Data and records on efficacy dimensions of skin textures, elasticity, firmness, pores, gloss and stratum corneum hydration for retinol in the Chinese population are supplemented with our study. Cosmeceutical approaches targeting both static and dynamic wrinkles are of value for treating the photoaged Chinese population.

Machine-learning-assisted SERS nanosensor platform toward chemical fingerprinting of Baijiu flavors.

A novel fingerprinting platform for multiplex detection of flavor molecules in Baijiu was developed by using a surface-enhanced Raman scattering (SERS) nanosensor array in combination with machine learning. The SERS sensors were constructed by core-shell Fe3O4@Ag nanoparticles modified with molecules carrying end-groups of hydroxyl, pyridyl, methyl, and amino, respectively, which interacted with flavors and led to changes in the sensors' spectra. All the Raman spectra acquired from the nanosensor array contacting with the sample were concatenated into a single SERS super-spectrum, representing the flavor fingerprint which was recognized through machine learning. Principal component analysis, support vector machine, and partial least squares were utilized to build classification and quantitation models for predictive analyses. The SERS nanosensor array was successfully used for fingerprinting ten typical flavors in Baijiu including four esters, three alcohols, and three acids, with an accuracy of 100%, linear detection ranges over two orders of magnitude, and limits of detection ranging from 3.45 × 10-3 mg/L of phenylethyl acetate to 1.21 × 10-2 mg/L of ethyl hexanoate. It was also demonstrated that satisfactory accuracies (recoveries) ranging from 96.2 to 104% and relative standard deviations ranging from 0.65 to 2.78% were obtained for the simultaneous quantification of 3-methylbutyl acetate and phenylethyl acetate in eighteen Baijiu samples of three flavor types including sauce flavor, strong flavor, and light flavor. Compared with the existing detection techniques, this chemical fingerprinting platform is easy to use, highly sensitive, and can perform multiplex detection, which has great potential for practical applications.

Quantitative PCR of string-test collected gastric material: A feasible approach to detect Helicobacter pylori and its resistance against clarithromycin and levofloxacin for susceptibility-guided therapy.

BACKGROUND: As the reduced eradication rate of Helicobacter pylori (H. pylori), we introduced string-test and quantitative PCR (qPCR) for susceptibility-guided therapy innovatively. The practicality of the string test was evaluated. METHODS: It was an open-label, non-randomized, parallel, single-center study, in which subjects tested by 13 C- urea breath test (UBT) and string-qPCR were enrolled. Based on the results of string-qPCR, we calculated clarithromycin and levofloxacin resistance rates and gave 13 C-UBT positive patients 14 days susceptibility-guided bismuth quadruple therapy. In the empirical therapy group, we retrospectively analyzed the treatment results of 13 C-UBT positive patients also treated with bismuth quadruple at Shenzhen Luohu People's Hospital from January 2021 to May 2022. The eradication rate was compared between susceptibility-guided therapy and empirical therapy groups. RESULTS: The diagnosis of H. pylori infection using the string-qPCR had an overall concordance rate of 95.9% with the 13 C-UBT results. Based on the results of string-qPCR, the clarithromycin and levofloxacin resistance rates were 26.1% and 31.8%, respectively. The patients who were given 14 days susceptibility-guided bismuth-based quadruple therapy achieved a high H. pylori eradication rate of 91.8%. Retrospective analysis of patient treatment data from January 2021 to May 2022 available in the hospital database revealed an overall success rate of 82.3% for those who received empirical bismuth-based quadruple therapies, which is marginally significantly lower than that of the string-qPCR susceptibility-guided group (p = 0.084). CONCLUSION: The high treatment success rate of 91.8% indicates that the string-qPCR test is a valuable and feasible approach for clinical practice to help improve H. pylori treatment success rate.

The interaction between dietary fiber and gut microbiota, and its effect on pig intestinal health.

Intestinal health is closely associated with overall animal health and performance and, consequently, influences the production efficiency and profit in feed and animal production systems. The gastrointestinal tract (GIT) is the main site of the nutrient digestive process and the largest immune organ in the host, and the gut microbiota colonizing the GIT plays a key role in maintaining intestinal health. Dietary fiber (DF) is a key factor in maintaining normal intestinal function. The biological functioning of DF is mainly achieved by microbial fermentation, which occurs mainly in the distal small and large intestine. Short-chain fatty acids (SCFAs), the main class of microbial fermentation metabolites, are the main energy supply for intestinal cells. SCFAs help to maintain normal intestinal function, induce immunomodulatory effects to prevent inflammation and microbial infection, and are vital for the maintenance of homeostasis. Moreover, because of its distinct characteristics (e.g. solubility), DF is able to alter the composition of the gut microbiota. Therefore, understanding the role that DF plays in modulating gut microbiota, and how it influences intestinal health, is essential. This review gives an overview of DF and its microbial fermentation process, and investigates the effect of DF on the alteration of gut microbiota composition in pigs. The effects of interaction between DF and the gut microbiota, particularly as they relate to SCFA production, on intestinal health are also illustrated.

Single-cell profiling of the microenvironment in decidual tissue from women with missed abortions.

OBJECTIVE: To define the decidual microenvironment in euploid and aneuploid missed abortions and elective termination of pregnancies. DESIGN: Prospective, multicenter, observational study. SETTING: Tertiary hospital and descriptive analysis of transcriptomic data. PATIENT(S): A total of 34 patients experienced abortions, including 6 women who underwent elective terminations of pregnancy of unplanned pregnancies and 28 cases with missed abortions. All patients underwent their operations from Sep, 2021 to Sep, 2022. INTERVENTION(S): All women underwent villous copy number variation sequencing. Meanwhile, single-cell RNA sequencing were performed in the decidual tissues of 16 women, and reverse transcription quantitative polymerase chain reaction were performed in the decidual tissues of 18 women. MAIN OUTCOME MEASURE(S): Single-cell RNA sequencing was used to explore the changes in the microenvironment of decidual tissues in abortions. RESULT(S): Single-cell RNA sequencing indicated that the microenvironment of the decidual tissue of the missed-abortion group was altered, and that the stromal cells (SCs), natural killer cells, macrophages, and epithelial cells all reflected functional imbalances compared with the elective terminations of pregnancy group. We also noted a correlation between the proportion of senescent SCs and chromosomal abnormalities in missed-abortion embryos. The proportion of senescent decidual SCs in the decidual tissue of missed-abortion patients with common chromosomal abnormalities of the fetus was higher, and this was not conducive to fetal growth and was closely related to missed abortion. In addition, we ascertained that the strength of the HLA-KIR interaction between NK1 and NK2 subsets and non-senescent stromal cell subsets in the missed abortion decidual tissues was weakened, potentially playing a role in the occurrence of missed abortion. CONCLUSION(S): The decidualization of SCs in the missed-abortion decidual tissues was impaired, the clearance of senescent SCs by NK cells was weakened, the killing toxicity of non-senescent SCs was enhanced, macrophages were insufficiently resident at the maternal-fetal interface, and epithelial cell differentiation was unbalanced-all creating a maternal microenvironment that was not conducive to fetal growth. We posit that interfering with the expression of dysregulated genes in the missed-abortion decidual tissues and reversing the maternal microenvironment might constitute an effective means toward improving the clinical outcome of missed abortions. Intriguingly, we observed a correlation between stromal cell senescence and embryonic chromosomal abnormalities. Thus, we hypothesize that the DIO2 marker of senescent SCs can be used as a risk indicator for the occurrence of missed miscarriages with chromosomal abnormalities of the embryos, and that it can be applied to guide the clinical diagnosis and treatment of recurrent abortion. CLINICAL TRIAL REGISTRATION NUMBER: NCT04425317.

The Triglyceride Glucose Index Is a Risk Factor for Enlarged Perivascular Space.

The triglyceride glucose (TyG) index is considered a simple surrogate marker for insulin resistance and has been associated with cerebrovascular diseases. However, limited information is available regarding its association with the subclinical cerebral small vessel disease (CSVD). Here, we investigated the association of TyG index with the burden and distribution of enlarged perivascular space (EPVS) in the non-diabetic population. The data of 531 non-diabetic patients from 2017 to 2020 were assessed. Participants were grouped according to the burden of EPVS. TyG index was calculated using the log scale of fasting triglycerides (mg/dl) × fasting glucose (mg/dl)/2. The association of TyG index with EPVS burden and distribution was evaluated. In the multivariable logistic regression analysis, the TyG index was associated with moderate to severe EPVS [odds ratio (OR): 2.077; 95% CI = 1.268-3.403]. The TyG index was significantly associated with an increased risk of moderate to severe EPVS in subgroups of age <65 years, male, diastolic blood pressure (DBP) <90 mmHg, low-density lipoprotein cholesterol (LDL-C) ≥2.85 mmol/L, serum homocysteine <10 µmol/L, and estimated glomerular filtration rate (eGFR) <90 ml/min/1.73 m2, as well as those without smoking. Further analysis of EPVS distribution, the TyG index was found to be associated with moderate to severe EPVS in the centrum semiovale (CSO), not in the basal ganglia (BG). Conclusively, the TyG index was independently and positively associated with moderate to severe CSO EPVS. TyG index may serve as an independent risk factor for CSVD in clinical practice.

Effects of Dietary Zinc Sources on Growth Performance and Gut Health of Weaned Piglets.

The present study aimed to investigate the effects of dietary zinc sources on the growth performance and gut health of weaned piglets. In total, 96 Duroc × Landrace × Yorkshire (DLY) weaned piglets with an initial average body weight of 8.81±0.42kg were divided into four groups, with six replicates per treatment and four pigs per replicate. The dietary treatment groups were as follows: (1) control group, basal diet; (2) zinc sulphate (ZnSO4) group, basal diet +100mg/kg ZnSO4; (3) glycine zinc (Gly-Zn) group, basal diet +100mg/kg Gly-Zn and (4) zinc lactate group, and basal diet +100mg/kg zinc lactate. The whole trial lasted for 28days. Decreased F/G was noted in the Gly-Zn and zinc lactate groups (p<0.05). The zinc lactate group had a lower diarrhea rate than the control group (p<0.05). Moreover, the ZnSO4, Gly-Zn, and zinc lactate groups had significantly higher apparent total tract digestibility of dry matter (DM), crude protein (CP), ether extract (EE), crude ash, and zinc than the control group (p<0.05). The Gly-Zn and zinc lactate groups had higher jejunal villus height and a higher villus height:crypt depth ratio than the control group (p<0.05). In addition, the ZnSO4, Gly-Zn and zinc lactate groups had a significantly lower mRNA expression level of jejunal ZRT/IRT-like protein 4 (ZIP4) and higher mRNA expression level of jejunal interleukin-1ß (IL-1ß) than the control group (p<0.05). The mRNA expression level of jejunal zinc transporter 2 (ZNT2) was higher and that of jejunal Bcl-2-associated X protein (Bax) was lower in the Gly-Zn and zinc lactate groups than in the control group (p<0.05). Moreover, the zinc lactate group had a higher count of Lactobacillus spp. in the cecal digesta and higher mRNA expression levels of jejunal occludin and mucin 2 (MUC2) than the control group (p<0.05). In conclusion, dietary supplementation with 100mg/kg ZnSO4, Gly-Zn, or zinc lactate could improve the growth performance and gut barrier function of weaned piglets. Dietary supplementation with organic zinc, particularly zinc lactate, had the best effect.

Diagnosis of Schizophrenia Based on Deep Learning Using fMRI.

Schizophrenia is a brain disease that frequently occurs in young people. Early diagnosis and treatment can reduce family burdens and reduce social costs. There is no objective evaluation index for schizophrenia. In order to improve the classification effect of traditional classification methods on magnetic resonance data, a method of classification of functional magnetic resonance imaging data is proposed in conjunction with the convolutional neural network algorithm. We take functional magnetic resonance imaging (fMRI) data for schizophrenia as an example, to extract effective time series from preprocessed fMRI data, and perform correlation analysis on regions of interest, using transfer learning and VGG16 net, and the functional connection between schizophrenia and healthy controls is classified. Experimental results show that the classification accuracy of fMRI based on VGG16 is up to 84.3%. On the one hand, it can improve the early diagnosis of schizophrenia, and on the other hand, it can solve the classification problem of small samples and high-dimensional data and effectively improve the generalization ability of deep learning models.

The Effect of Ellagic Acid on Hepatic Lipid Metabolism and Antioxidant Activity in Mice.

Accumulating evidence has demonstrated that the imbalance of lipid metabolism and antioxidant capacity leads to damage to liver. The present study aimed to investigate the effects of ellagic acid (EA), a phenolic compound, on hepatic lipid metabolism and antioxidant activity in mice. In our study, 24 C57BL/6J mice were divided into three groups: (1) control (CON); (2) basal diet+0.1% EA (EA1); and (3) basal diet+0.3% EA (EA2). After the 14-day experiment, the liver was sampled for analysis. The results showed that 0.3% EA administration increased the liver weight. Total cholesterol and low-density lipoprotein cholesterol activities decreased and high-density lipoprotein cholesterol activity increased by EA supplementation. Meanwhile, dietary supplementation with EA dose-dependently decreased the acetyl-CoA carboxylase protein abundance and increased the phospho-hormone-sensitive lipase, carnitine palmitoyltransferase 1B, and peroxisome proliferator-activated receptor alpha protein abundances. Moreover, EA supplementation reduced the malonaldehyde concentration and increased the superoxide dismutase and catalase concentrations. The protein abundances of phospho-nuclear factor-E2-related factor 2, heme oxygenase-1, and NAD(P)H: quinone oxidoreductase 1 increased by EA supplementation in a dose-dependent manner. Taken together, EA supplementation promoted the lipid metabolism and antioxidant capacity to maintain the liver health in mice.

Grazing and Supplementation of Dietary Yeast Probiotics Shape the Gut Microbiota and Improve the Immunity of Black Fattening Goats (Capra hircus).

This study aimed to investigate the effects of different feeding modes on the growth performance, gut microbiota, and immunity of Black Fattening Goat (Capra hircus). A total of 30 goats were grouped in three groups by their feeding modes (pasture grazing group, PG; barn feeding group, BF; barn feeding + probiotics, BF + P; n = 10) and the study was performed for 114 days. After a 2-week adaptation period, the first growth performance test was conducted, and the blood and fecal samplings (day 0) were collected on January 17, 2020, while the second and third test and samplings were conducted on days 53 and 100 of feeding. The species-composition of fecal microbiota was analyzed by 16S ribosomal RNA gene-sequencing using PacBio single molecule real time (SMRT) sequencing technology. Both the BF and BF + P groups had the highest (P < 0.05) body's weight and length, and chest circumference at days 53 and 100, especially at day 100, the body's weight of both the BF groups were more than 18 kg. The levels of immunoglobulin A (IgA) and immunoglobulin G (IgG) were found to be significantly higher (P < 0.05) in the PG and BF + P groups at day 100. The PG group exhibited the highest number of operational taxonomic unit (OTUs) and alpha diversity. Firmicutes, Bacteroidetes, and Verrucomicrobia were the predominant phyla in all the fecal samples. The relative abundance of Akkermansia muciniphila and Ruminococcus flavefaciens were found to be significantly higher (P < 0.05) in PG group and BF + P group at day 100, respectively, which might partially explain the significantly higher (P < 0.05) levels of IgA and IgG in these two groups. These findings suggested that BF supplemented with 5 g probiotics (Saccharomyces cerevisiae and mannan oligosaccharides) per day has the potential to enhance the growth and immunity of Black Fattening Goats.

An all-in-one magnetic SERS nanosensor for ratiometric detection of Escherichia coli in foods.

An all-in-one nanosensor was developed for the magnetic enrichment and ratiometric surface-enhanced Raman scattering (SERS) detection of Escherichia coli (E. coli). The all-in-one nanosensor was constructed through the chemical integration of four components into a single nanoparticle, which include a manganese ferrite nanoparticle serving as the magnetic core, a thin silver shell as the SERS substrate, a self-assembled layer of 4-mercaptobenzoic acid (MBA) molecules as the SERS internal standard, and a MBA-conjugated layer of aptamer sequences as the capture probe of E. coli. In the detection of E. coli in food, the target cells were first captured by the nanosensors and magnetically enriched in a short time of 15 min, and then the ratiometric SERS was performed through the Raman intensity ratio between two specific SERS peaks produced by the captured E. coli and the internal MBA. The pre-concentration and ratiometry enabled the nanosensor to detect E. coli with a detection limit down to 10 CFU/mL. The all-in-one nanosensor was successfully applied for the detection of E. coli in various liquid foods including milk, juice, tea, and coffee, with recoveries ranging from 89 to 110% and relative standard deviation lower than 1.7%. In comparison with the previous sandwich strategy adopted by most SERS sensors, this nanosensor endowed with an easier use and a lower cost is more sensitive and reproducible, leading to a great potential in practical applications.

Phoenixin-20 Prevents ox-LDL-Induced Attachment of Monocytes to Human Aortic Endothelial Cells (HAECs): A Protective Implication in Atherosclerosis.

The exact cause of atherosclerosis is not known, and therefore, the current treatment options are limited. The activation of endothelial cells by oxidized low-density lipoprotein (ox-LDL) plays a key role in the initiation and progression of atherosclerosis. Phoenixin-20 is one of the newly identified neuropeptides with pleiotropic effects in the regulation of reproduction and other biological functions. G-protein receptor-coupled 173 (GPR173) is the putative receptor of Phoenixin-20. In the present study, we show that endothelial GPR173 is repressed upon ox-LDL stimulation in human aortic endothelial cells (HAECs). We further elaborate on the hypothesis that GPR173 could be involved in the pathogenesis of atherosclerosis through a series of experiments. Our results indicate that ox-LDL remarkably triggers the increase of ROS, NOX-4, pro-inflammatory cytokines IL-1ß, IL-8, and MCP-1 expression, as well as adhesion molecules ICAM-1 and VCAM-1 release. However, the agonism of GPR173 using Phoenixin-20 significantly ameliorates all of these harmful effects from ox-LDL by suppressing the NF-κB pathway. Furthermore, we show that agonism of GPR173 by Phoenixin-20 prevents the attachment of monocytes THP-1 to endothelial cells, which is an important therapeutic approach to preventing atherogenesis. In conclusion, our study demonstrates that GPR173 agonism by Phoenixin-20 plays a protective role against ox-LDL-induced endothelial dysfunction, implying that Phoenixin-20 may have therapeutic implications in atherosclerosis.

Complete Genome Sequence and Biodegradation Characteristics of Benzoic Acid-Degrading Bacterium Pseudomonas sp. SCB32.

Allelochemicals are metabolites produced by living organisms that have a detrimental effect on other species when released into the environment. These chemicals play critical roles in the problems associated with crop replanting. Benzoic acid is a representative allelochemical found in root exudates and rhizosphere soil of crops and inhibits crop growth. The bioremediation of allelochemicals by microorganisms is an efficient decontamination process. In this research, a bacterial strain capable of degrading benzoic acid as the sole carbon source was isolated. The genome of the strain was sequenced, and biodegradation characteristics and metabolic mechanisms were examined. Strain SCB32 was identified as Pseudomonas sp. based on 16S rRNA gene analysis coupled with physiological and biochemical analyses. The degradation rate of 800 mg L-1 benzoic acid by strain SCB32 was greater than 97.0% in 24 h. The complete genome of strain SCB32 was 6.3 Mbp with a GC content of 64.6% and 5960 coding genes. Potential benzoic acid degradation genes were found by comparison to the KEGG database. Some key intermediate metabolites of benzoic acid, such as catechol, were detected by gas chromatography-mass spectrometry. The biodegradation pathway of benzoic acid, the ortho pathway, is proposed for strain SCB32 based on combined data from genome annotation and mass spectrometry. Moreover, the benzoic acid degradation products from strain SCB32 were essentially nontoxic to lettuce seedlings, while seeds in the benzoic acid-treated group showed significant inhibition of germination. This indicates a possible application of strain SCB32 in the bioremediation of benzoic acid contamination in agricultural environments.

Higher quantum efficiency and moisture resistance of all-inorganic halide perovskite nanocrystal films in situ fabricated with cyclodextrin.

Supermolecule ß-cyclodextrin was used to assist CsPbBr3 film fabrication. In situ growth of nanocrystals was effectively confined through strong interactions between perovskite Pb2+ ions and ß-CD hydroxyl groups, producing a compact and smooth film. The quantum efficiency achieved was 85.3% with a moisture resistance over months, exceeding the record of perovskite films.

Curcumin Acetate Nanocrystals for sustained Pulmonary Delivery: Preparation, Characterization and In Vivo Evaluation.

The main objective of this study was to test the hypothesis that inhaled nanocrystals of a highly lipophilic drug could be used as a novel approach for producing sustained pulmonary delivery. Curcumin acetate, an ester prodrug of curcumin, was utilized as a highly lipophilic model drug. Curcumin acetate was subjected to wet ball milling to produce different particle sizes of nanocrystals and microparticles, and the milled curcumin acetate was spray-dried to yield similar inhalable microparticles. Following intrapulmonary administration in rats, pharmacokinetic experiments indicated that curcumin acetate significantly extended the pulmonary absorption time by 7.2-fold compared to curcumin, possibly due to the high lipophilicity of the former. The biodistribution data showed that aerosolized curcumin acetate nanocrystals 123.7 nm in size not only prolonged pulmonary retention, with the AUC value of curcumin acetate being 7.62-fold higher than that of the microparticles 1120 nm in size, but also increased the local in vivo release rate by 3.3-fold and the local availability of converted curcumin by 25.1-fold. In addition, the improved local availability resulted in better pharmacological efficacy in a monocrotaline-induced rat model of pulmonary arterial hypertension. This study was the first to demonstrate that inhalable nanocrystals are a feasible means for the sustained pulmonary delivery of highly lipophilic drugs.

Electrodeposition of polyaniline onto TiO2 nanoparticles/multiwalled carbon nanotubes for visible light photoelectrocatalysis.

In this study, polyaniline (PANI) was coated onto TiO2 nanoparticles/multiwalled carbon nanotubes (TiO2/MWCNTs) hybrid by electrochemical polymerization. Modification of TiO2/MWCNTs with PANI endows the resulted hybrid with visible light activity. The PANI/TiO2/MWCNTs hybrid shows remarkable photoelectrocatalytic activity for the degradation of RhB under visible light irradiation. The enhanced photocatalytic activity of the PANI/TiO2/MWCNTs hybrid originates from the effective charge transfer properties of the heterojunctions of PANI-TiO2 and TiO2-MWCNTs. The efficient charge transportation and high photoelectrocatalytic activity towards degradation of rhodamine B make this novel hybrid material promising for photocatalysis and for the development of photoelectrical devices.

Acoustic sensing of the initial adhesion of chemokine-stimulated cancer cells.

Chemokines together with their receptors play important roles in tumor metastasis. Intracellular signals stimulated by chemokines regulate the initial adhesion of cancer cells, which controls the subsequent cell spreading and migration. Until now, the nature of initial cell adhesion has been understood very poorly, since conventional assays are static and could not provide dynamic information. In order to address this issue, we adopt an acoustic sensor, quartz crystal microbalance (QCM), to monitor the attachment of chemokine-stimulated cancer cells in real-time. As a model, the chemokine CXCL12 was used to stimulate three human breast cancer cell lines expressing different levels of its receptor CXCR4, which triggers intracellular signaling pathways that activate integrins across cell membrane. Interaction between cellular integrins and adhesion molecules (CAMs) pre-coated on sensor surfaces were in situ monitored by QCM of which the frequency was sensitive to the mechanical connection of cells to the sensor surface. The ratio of frequency shift under stimulation to that without stimulation indicated the number and strength of integrin-CAM binding stimulated by the chemokine. The cell-surface binding was found to be enhanced by CXCL12, which depends on the CAM type and levels of chemokine and receptor, and was significantly inhibited by a blocker of the chemokine pathway. The binding of integrin with intercellular adhesion molecule was also found to be strong and in good correlated with the chemotactic indexes obtained by the classical Boyden chamber assay. This research suggests that acoustic sensing of initial cell adhesion could provide a dynamic insight into cell interfacial phenomena.