A new substrate equalization method for optimizing the influent conditions and fluid flow patterns of a multifed upflow anaerobic sludge blanket reactor with mature anammox granules.

To improve nitrogen removal efficiency (NRE) and achieve homogenous distribution of anammox sludge and substrate, a new substrate equalization theory and a cumulative overload index was proposed for multifed upflow anaerobic sludge bed (MUASB) reactors with mature anammox granules. The performance and flow patterns of MUASB reactors were investigated under various influent conditions. The results showed that the nitrogen removal performance and stability of MUASB reactors could be optimized by minimizing the cumulative load. The NRE gradually increased from 83.3 ± 2.2 %, 86.8 ± 4.2 % to 89.3 ± 4.1 % and 89.7 ± 1.6 % in feeding flow tests and feeding port tests, respectively. Furthermore, the flow patterns were compared based on residence time distribution and computational fluid dynamics, indicating that a better equilibrium distribution of microorganisms and substrates could be achieved in the MUASB reactors under the lowest cumulative load. Therefore, substrate equalization theory can be used to optimize the nitrogen removal performance of MUASB reactors with low-carbon footprints.

Prevalence and genetic diversity of human rhinovirus among patients with acute respiratory infections in China, 2012-2021.

To understand the prevalence of rhinovirus (RV) among acute respiratory infection (ARI) patients, 10-year ARI surveillance in multiple provinces of China were conducted during 2012-2021. Of 15 645 ARI patients, 1180 (7.54%) were confirmed to have RV infection and 820 (69.49%) were children under 5 years of age. RV typing was performed on the 527 VP1 gene sequences, and species A, B, and C accounted for 73.24%, 4.93%, and 21.82%, respectively. Although no significant difference in the proportions of age groups or disease severity was found between RV species, RV-C was more frequently detected in children under 5 years of age, RV-A was more frequently detected in elderly individuals (≥60), and the proportions of pneumonia in RV-A and RV-C patients were higher than those in RV-B patients. The epidemic peak of RV-A was earlier than that of RV-C. A total of 57 types of RV-A, 13 types of RV-B, and 35 types of RV-C were identified in RV-infected patients, and two uncertain RV types were also detected. The findings showed a few differences in epidemiological and clinical features between RV species in ARI patients, and RV-A and RV-C were more prevalent than RV-B.

A review of recent studies on valve-less piezoelectric pumps.

Due to the advantages of small size, low power consumption and price, no wear, and reliable performances of valve-less piezoelectric pumps, which academics have studied and gained excellent consequences for, valve-less pumps are applied in the following fields: fuel supply, chemical analysis, biological fields, drug injection, lubrication, irrigation of experiment fields, etc. In addition, they will broaden the application scope in micro-drive fields and cooling systems in the future. During this work, first, the valve structures and output capabilities of the passive valve and active valve piezoelectric pumps are discussed. Second, the various forms of symmetrical structure, asymmetrical structure, and drive variant structure valve-less pumps are introduced, the working processes are illustrated, and the advantages and disadvantages of pump characteristics with the flow rate and pressure are analyzed under different driving conditions. In this process, some optimization methods with theoretical and simulation analysis are explained. Third, the applications of valve-less pumps are analyzed. Finally, the conclusions and future development of valve-less piezoelectric pumps are given. This work attempts to provide some guidance for enhancing output performances and applications.

Identification of two proposed novel human rhinovirus types: Bpat107 and Cpat58.

Human rhinovirus (RV) is an important viral pathogen associated with severe acute respiratory tract infection. The present study retrospectively identified RV types in hospitalized patients with severe acute respiratory infection (SARI) from October 2017 to June 2019 in Henan Province, China. Real-time PCR was used to screen pharyngeal swab samples for RV. Then, the VP1 gene sequences of RV-positive samples were amplified and sequenced with nested primer PCR; subsequently, analyses of the molecular epidemiology and genetic diversity characteristics of the RV types were performed. Seventy-three out of 1015 respiratory samples were identified as RV-positive, from which 65 complete VP1 sequences were successfully sequenced. These RVs were classified into 41 different types, including 26 RV-A types, 2 RV-B types, and 13 RV-C types. The RVs showed an obvious seasonal distribution, with peaks in summer and autumn. The epidemic peak of RV-C was later than that of RV-A. In addition, two new types of species, B and C, were proposed, Bpat107 and Cpat58, respectively. Compared with other types in the same RV species, the pairwise nucleotide p-distances of the two novel RV types were 0.262~0.402 and 0.251~0.508, respectively. This study analyzed the seasonal and genetic characteristics of RV associated with SARI cases in Henan Province, China. Two novel RV types were proposed.

Combining curcumin and aspirin ameliorates preeclampsia-like symptoms by inhibiting the placental TLR4/NF-κB signaling pathway in rats.

AIM: Preeclampsia (PE) is a common medical complication of pregnancy characterized by high blood pressure and proteinuria after the 20th gestational week. This study aimed to investigate the potency of the combination of curcumin and aspirin in the treatment of PE and explore the underlying mechanisms. MATERIAL AND METHODS: The PE model was constructed in female rats by administering 0.5 mg/mL N-nitro-L-arginine methyl ester from gestational days (GDs) 6 to 16. The pregnant female rats were divided into five groups according to the drug treatment. The curcumin or aspirin was given to the rats by tail vein injection (0.36 mg/kg) or gavage treatment (1.5 mg/kg BW/day) from GD4 to GD18. RESULTS: Treatment with curcumin and aspirin combination significantly reduced the systolic blood pressure and proteinuria in the PE rats. Meanwhile, in comparison to the PE rats treated with single-dose curcumin or aspirin, the rats treated with combined curcumin and aspirin showed significantly decreased sFlt-1, increased placental growth factor, and alleviated oxidative stress in both blood and placental tissues, which are abnormal in no-treated PE rats. Furthermore, dramatically decreased inflammatory cytokines secretion and TLR4 and NF-κB p65 expression in placental tissues were also observed in the PE rats with combined treatment compared to those of no-treated, signal-dose curcumin or aspirin-treated PE rats. CONCLUSIONS: Our results suggested that the combined treatment of curcumin and aspirin significantly ameliorates the symptoms of PE in rats, which is most likely due to the inhibition of the placental TLR4/NF-κB p65 signaling pathway.

Effects of healthcare failure mode and effect analysis on the prevention of multi-drug resistant organisms infections in oral and maxillofacial surgery.

OBJECTIVE: Care models of Healthcare Failure Mode and Effect Analysis (FMEA) were evaluated for the prevention of multi-drug resistant organisms (MDRO) infections in oral and maxillofacial surgery. METHODS: Two hundred patients who received oral and maxillofacial surgery from January to December 2017 were enrolled as the control group, and another 200 patients who received oral and maxillofacial surgery from January to December 2018 were enrolled as the FMEA group. The incidence of MDRO, the implementation of preventive and control measures, the mastery of preventive and control knowledge, and oral self-care ability were compared between the two groups. Risk Priority Number (RPN) and behavioral changes of health care personnel were observed in FMEA group. RESULTS: The FMEA group had a lower incidence of MDRO (2.00%) than the control group (6.00%) and a higher rate of acquisition of prevention and control knowledge (93.00%) than the control group (84.50%) (P < 0.05). Patients in FMEA group were higher than those in the control group in terms of compliance towards isolation signs and precautions, appropriate use of PPE, implementation of disinfection measures, hand hygiene and exercise of self-care agency (ESCA) scale scores (P < 0.05). The total RPN score of the FMEA group before and after management was 1384 and 180, respectively, and the reduction rate of total RPN scores was 86.99%. Scores with regard to knowledge, attitude, and behavior of health care personnel were increased after FMEA treatment (P < 0.05). CONCLUSION: The nursing model of FMEA for oral and maxillofacial surgery can prevent MDRO infections, reduce RPN, improve the implementation of preventive and control measures as well as oral self-care ability and the acquisition of knowledge.

The Acidic Fraction of Isatidis Radix Regulates Inflammatory Response in LPS-Stimulated RAW264.7 Macrophages through MAPKs and NF-κB Pathway.

Isatidis Radix, the dried root of Isatidis indigotica Fort, is a traditional heat-clearing and detoxicating herb, which has the antiviral and anti-inflammatory activity and immune regulation. It has been widely used to treat cold, fever, sore throat, mumps, and tonsillitis in clinics. A previous study demonstrated that the acidic fraction of Isatidis Radix (RIAF) had strong anti-inflammatory activity, but the mechanism of action was not well elucidated. Lipopolysaccharide- (LPS-) induced RAW264.7 cells were employed to observe the anti-inflammatory activity of RIAF. The level of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), nitric oxide (NO), prostaglandin E2 (PGE2), and interleukin-6 (IL-6) was determined by enzyme-linked immunosorbent assay kits. Western blot was performed to quantify the expression of extracellular signal-regulated kinase (ERK) 1/2, c-jun NH2-termianl kinase (JNK), p38, inducible NO synthetase (iNOS), cyclooxygenase (COX)-2, andnuclear factor-κB (NF-κB). Immunofluorescence assay and electrophoretic mobility shift assay (EMSA) were used to quantify the translocation and the binding-DNA activity of NF-κB. RIAF could inhibit the secretion of inflammatory cytokines (PGE2, IL-6, IL-1ß, and NO, other than TNF-α) in a dose-dependent manner. Further investigation showed that the expression of iNOS and COX-2 induced by LPS were downregulated by treatment with RIAF. Meanwhile, data from the signal pathway exhibited that RIAF significantly suppressed the phosphorylation of ERK1/2, JNK, and p38 and reduced the translocation of NF-κB from the cytoplasm to nucleus, as well as the binding-DNA activity. The anti-inflammatory mechanism of action of RIAF was to reduce inflammation-associated gene expression (iNOS, COX-2, IL-1ß, IL-6) by regulating the phosphorylation of the mitogen-activated protein kinases (MAPK) pathway and interventing the activation of the NF-κB pathway, which partly illustrated the basis of treatment of Isatidis Radix on cold, fever, sore throat, mumps, and tonsillitis in clinics.

Early prediction and identification for severe patients during the pandemic of COVID-19: A severe COVID-19 risk model constructed by multivariate logistic regression analysis.

BACKGROUND: As an emergent and fulminant infectious disease, Corona Virus Disease 2019 (COVID-19) has caused a worldwide pandemic. The early identification and timely treatment of severe patients are crucial to reducing the mortality of COVID-19. This study aimed to investigate the clinical characteristics and early predictors for severe COVID-19, and to establish a prediction model for the identification and triage of severe patients. METHODS: All confirmed patients with COVID-19 admitted by the Second Affiliated Hospital of Air Force Medical University were enrolled in this retrospective non-interventional study. The patients were divided into a mild group and a severe group, and the clinical data were compared between the two groups. Univariate and multivariate analysis were used to identify the independent early predictors for severe COVID-19, and the prediction model was constructed by multivariate logistic regression analysis. Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of the prediction model and each early predictor. RESULTS: A total of 40 patients were enrolled in this study, of whom 19 were mild and 21 were severe. The proportions of patients with venerable age (≥60 years old), comorbidities, and hypertension in severe patients were higher than that of the mild (P < 0.05). The duration of fever and respiratory symptoms, and the interval from illness onset to viral clearance were longer in severe patients (P < 0.05). Most patients received at least one form of oxygen treatments, while severe patients required more mechanical ventilation (P < 0.05). Univariate and multivariate analysis showed that venerable age, hypertension, lymphopenia, hypoalbuminemia and elevated neutrophil lymphocyte ratio (NLR) were the independent high-risk factors for severe COVID-19. ROC curves demonstrated significant predictive value of age, lymphocyte count, albumin and NLR for severe COVID-19. The sensitivity and specificity of the newly constructed prediction model for predicting severe COVID-19 was 90.5% and 84.2%, respectively, and whose positive predictive value, negative predictive value and crude agreement were all over 85%. CONCLUSIONS: The severe COVID-19 risk model might help clinicians quickly identify severe patients at an early stage and timely take optimal therapeutic schedule for them.

Comparative Genomic Analysis of a Multidrug-Resistant Listeria monocytogenes ST477 Isolate.

Listeria monocytogenes is an opportunistic human foodborne pathogen that causes severe infections with high hospitalization and fatality rates. Clonal complex 9 (CC9) contains a large number of sequence types (STs) and is one of the predominant clones distributed worldwide. However, genetic characteristics of ST477 isolates, which also belong to CC9, have never been examined, and little is known about the detail genomic traits of this food-associated clone. In this study, we sequenced and constructed the whole-genome sequence of an ST477 isolate from a frozen food sample in China and compared it with 58 previously sequenced genomes of 25 human-associated, 5 animal, and 27 food isolates consisting of 6 CC9 and 52 other clones. Phylogenetic analysis revealed that the ST477 clustered with three Canadian ST9 isolates. All phylogeny revealed that CC9 isolates involved in this study consistently possessed the invasion-related gene vip. Mobile genetic elements (MGEs), resistance genes, and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system were elucidated among CC9 isolates. Our ST477 isolate contained a Tn554-like transposon, carrying five arsenical-resistance genes (arsA-arsD, arsR), which was exclusively identified in the CC9 background. Compared with the ST477 genome, three Canadian ST9 isolates shared nonsynonymous nucleotide substitutions in the condensin complex gene smc and cell surface protein genes ftsA and essC. Our findings preliminarily indicate that the extraordinary success of CC9 clone in colonization of different geographical regions is likely due to conserved features harboring MGEs, functional virulence and resistance genes. ST477 and three ST9 genomes are closely related and the distinct differences between them consist primarily of changes in genes involved in multiplication and invasion, which may contribute to the prevalence of ST9 isolates in food and food processing environment.

Prevalence of Enterotoxin Genes in Staphylococcus aureus Isolates from Pork Production.

In this study, 130 Staphylococcus aureus isolates from samples associated with pork production were tested for prevalence of 18 staphylococcal enterotoxin (SE) genes. Approximately 94.6% (123/130) of isolates from different stages of pork production harbored one or more SE genes forming 37 different enterotoxin gene profiles. Seb was present in 60.0% of the S. aureus isolates, the highest among the genes tested. The genes, sed, sej, seo, sep, ser, and seu, were not found. The five classical SE genes (including sea, seb, sec, sed, see) had lower prevalence than the egc gene cluster (seg, sei, sem, sen, seo, or seu). Notably, ∼6.9% (9/130) isolates harbored five SE genes. Classical SE genes were relatively higher in raw meat isolates than swine farm isolates, suggesting that raw meat isolates have a greater potential for classical staphylococcal food poisoning. Incomplete egc clusters were mainly distributed in swine farm isolates, and some of them coexisted with other classical SE genes (seb, sec), showing that swine farms could be potential sources of enterogenic S. aureus of food safety concern. Characterizing the distributions of enterotoxin genes among S. aureus may provide epidemiological information for the benefit of public health and food safety.

Determination of polar components in frying oils by Fourier-transform near-infrared spectroscopy.

A rapid and convenient method was developed to determine the polar components (PC) of frying oil by Fourier-transform near-infrared (FTNIR) spectroscopy. One hundred twenty six oil samples were used to PC determination by column chromatography and FTNIR spectroscopy combined with partial least-square (PLS) calibration. The optimal PLS calibration was obtained after the Savitzky-Golay smoothing and first derivative treatment performed in the wavelength ranges of 4963 cm(-1) to 4616 cm(-1), 5222 cm(-1) to 5037 cm(-1), and 5688 cm(-1) to 5499 cm(-1). The obtained correlation coefficient (R) was 0.998 and the root mean square error of calibration was 1.0%. The PLS calibration was validated, and the results showed that the highest correlation (R) was 0.997 between reference value and the FTNIR predicted value and the root mean square error of prediction was 1.3%. Therefore, the FTNIR technique can be effectively applied to quantify PC with the advantages of simple operation and no pollution.