As important biocatalysts, nitrilases can efficiently convert nitrile groups into acids and ammonia in a mild and eco-friendly manner, being widely used in the synthesis of important pharmaceutical intermediates. Early studies reported that nitrilases only had the hydrolysis activity of catalyzing the formation of corresponding carboxylic acid products from nitriles, showing catalytic specificity. However, recent studies have shown that some nitrilases exhibit the hydration activity for catalyzing the formation of amides from nitriles, showing catalytic promiscuity. The catalytic promiscuity of nitrilases has dual effects. On the one hand, the presence of amide by-products increases the difficulties and costs of subsequent separation and purification of carboxylic acid products. On the other hand, however, if the catalytic reaction pathways of nitrilases can be precisely regulated to reshape enzyme functions, the reactions catalyzed by nitrilases can be broadened to provide new ideas for the biosynthesis of high-value amides, which is crucial for the development of artificial enzymes and biocatalysis. This review summarized the research progress in the catalytic promiscuity of nitrilases and discussed the key regulatory factors that may affect the catalytic promiscuity of nitrilases from the evolutionary origin, catalytic domains, and catalytic mechanisms, hoping to provide reference and inspiration for the application of nitrilases in biocatalysis.
Aminohydrolases/chemistry* ; Biocatalysis ; Nitriles/chemistry* ; Substrate Specificity ; Catalytic Domain ; Catalysis

Objective:To explore the effect of sacubitril/valsartan(LCZ696)on intestinal microbiota and serological parameters associ-ated with its derived metabolites in rats with right ventricular remodeling due to hypoxic pulmonary hypertension(HPH).Methods:A total of 24 male rats were randomly divided into Control group,Hypoxia group,and H-LCZ696 group.Since day 1,the rats in the H-LCZ696 group were given LCZ696 by gavage,while those in the other two groups were given normal saline by gavage,both for 4 con-secutive weeks.Related indicators were measured after experiment,including hemodynamics,color Doppler ultrasound of right heart,and right ventricular remodeling.Histopathological staining and transmission electron microscopy were used to observe tissue struc-tures;the metagenomics technique was used to analyze the characteristics and functional annotation of intestinal microbiota in the fe-ces of the rats;ELISA was used to measure the serological parameters of the metabolites derived from intestinal microbiota.Results:There was a significant difference in mean pulmonary arterial pressure(mPAP)between the three groups of rats(F=101.797,P=0.000).Compared with the Control group,the Hypoxia group had an increase in mPAP,a reduction in right ventricular function,and in-creases in the indicators for pulmonary vascular remodeling and right ventricular remodeling.Compared with the Hypoxia group,the H-LCZ696 group had a reduction in mPAP,an improvement in right ventricular function,and reductions in the indicators for pul-monary vascular remodeling and right ventricular remodeling.Trans-mission electron microscopy showed that the Hypoxia group had disordered myocardial myofibrils of the right ventricle and mitochon-drial swelling,while such ultrastructural damage was improved after LCZ696 intervention.The metagenomics analysis showed that the Hypoxia group had a reduction in the diversity of intestinal microbiota,with increases in the abundance of pathogenic bacteria(such as Proteobacteria,Prevotella,and Clostridium)and reductions in the abundance of probiotic bacteria(such as Lachnospiraceae and Lacto-bacillus),and such changes were partially reversed after LCZ696 intervention,with inhibition of the proliferation of pathogenic bacteria such as Clostridiales,the failure to restore the diversity of intestinal microbiota,and a further reduction in the abundance of some probi-otic bacteria(such as Lactobacillus).ELISA showed that compared with the Control group,the Hypoxia group had increases in the serum levels of pro-inflammatory metabolites,and compared with the Hypoxia group,the H-LCZ696 group had reductions in the se-rum levels of pro-inflammatory metabolites.Conclusion:LCZ696 can alleviate right ventricular remodeling in HPH and regulate pathogenic bacteria and serum pro-inflammatory metabolites,with a main therapeutic effect on the cardiovascular system and a regula-tory effect on intestinal microbiota.

Objective To compare the diagnostic values of different detection methods for respir-atory pathogens in children with acute respiratory infections.Methods A total of 862 children with a-cute respiratory infections were enrolled,and their throat swab samples were tested for seven common respiratory pathogens by the dual amplification method and a self-built nucleic acid detection system.For samples with inconsistent results between the two methods,nested polymerase chain reaction(PCR)was performed for verification.Results The positive detection rate of the dual amplification method was 57.75％,which was significantly higher than 30.14％of the self-built nucleic acid detec-tion system,and the detection rate of mixed infections was 10.14％,which was also significantly high-er than 1.97％of the self-built nucleic acid detection system(P＜0.05).The sensitivity of the dual amplification method was 91.63％,which was significantly higher than 72.61％of the self-built nu-cleic acid detection system,and the specificity was 92.31％,which was also significantly higher than 75.62％of the self-built nucleic acid detection system(P＜0.05).Conclusion The dual amplifica-tion method can simultaneously detect the ribonucleic acid of seven respiratory pathogens with high sensitivity and specificity,demonstrating significant clinical application value.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Tuberculosis (TB) is one of the deadly diseases caused by Mycobacterium tuberculosis (Mtb), which presents a significant public health challenge. Treatment of TB relies on the combination of several anti-TB drugs to create shorter and safer regimens. Therefore, new anti-TB agents working by different mechanisms are urgently needed. FtsZ, a tubulin-like protein with GTPase activity, forms a dynamic Z-ring in cell division. Most of FtsZ inhibitors are designed to inhibit GTPase activity. In Mtb, the function of Z-ring is modulated by SepF, a FtsZ binding protein. The FtsZ/SepF interaction is essential for FtsZ bundling and localization at the site of division. Here, we established a yeast two-hybrid based screening system to identify inhibitors of FtsZ/SepF interaction in M. tuberculosis. Using this system, we found compound T0349 showing strong anti-Mtb activity but with low toxicity to other bacteria strains and mice. Moreover, we have demonstrated that T0349 binds specifically to SepF to block FtsZ/SepF interaction by GST pull-down, fluorescence polarization (FP), surface plasmon resonance (SPR) and CRISPRi knockdown assays. Furthermore, T0349 can inhibit bacterial cell division by inducing filamentation and abnormal septum. Our data demonstrated that FtsZ/SepF interaction is a promising anti-TB drug target for identifying agents with novel mechanisms.

[This corrects the article DOI: 10.1016/j.apsb.2023.01.022.].

OBJECTIVE To analyze the dose-adjusted concentrations of Posaconazole oral suspension in patients undergoing hematopoietic stem cell transplantation （HSCT） and their influential factors. METHODS Data were collected from hospitalized HSCT patients admitted to the First Affiliated Hospital of Shandong First Medical University （Shandong Provincial Qianfoshan Hospital） from January 2021 to April whtwhm@yeah.net 2023 who took Posaconazole oral suspension for the prevention of invasive fungal disease （IFD） and received blood concentration of posaconazole. The rate of concentration attainment and clinical failure rate of posaconazole for the prevention of IFD were evaluated， and one-way and multiple linear regression analyses were performed for the influential factors of dose-adjusted concentrations （C0/D） of posaconazole. RESULTS A total of 44 patients were enrolled； the mean C0 of posaconazole in patients was （0.99±0.94） µg/mL， and 20 patients had a C0≥0.7 μg/mL， with a concentration attainment rate of 45.45% for the prevention of IFD； 13 cases were clinical failures， with a clinical failure rate of 29.55%. Of 24 patients who did not achieve C0/D of posaconazole for IFD prophylaxis， one patient was a clinical failure despite timely dose adjustment of posaconazole in seven patients； seven of the thirteen patients who did not undergo dose adjustment were clinical failures； and the remaining four patients were switched to other antifungal agents. The results of univariate analysis showed that gender， body mass index （BMI）， renal function， combined use of sodium phenytoin， omeprazole and metoclopramide had a significant effect on the C0/D of posaconazole （P＜0.05）； the results of multivariate linear regression analysis showed that gender， BMI and combined use of sodium phenytoin were the independent factors affecting the C0/D of posaconazole （P＜0.05）. CONCLUSIONS Significant individual differences are reflected in the blood concentration of Posaconazole oral suspension； gender， BMI and combined use of sodium phenytoin are independent factors affecting the C0/D of posaconazole.

Objective:This article takes the practical experience of the construction of the cardiovascular disease clinical medicine research center in Nanjing First Hospital as an example to provide reference for institutions preparing to build a clinical research center.Methods:The center conducts top-level design based on clinical needs, and this study systematically elaborates the construction of the center from management mechanisms, research platforms, collaborative networks, team building and international cooperation.Results:The center has made remarkable progress in clinical research, scientific and technological innovation, transformation and promotion, standard formulation, and technology leading. On the basis of an international perspective, the level of regional diagnosis and treatment has been improved by optimizing the structure of subject talents, and focusing on the clinical needs of cardiovascular subspecialty.Conclusions:Taking the construction of the clinical medicine center as an opportunity, integrating superior resources, improving the level of disease diagnosis, treatment and service and enhancing international academic influence are effective measures to accelerate the development of health services and deepen medical reforms.

Zika virus (ZIKV) is an emerging pathogen associated with neurological complications, such as Guillain-Barré syndrome in adults and microcephaly in fetuses and newborns. This mosquito-borne flavivirus causes important social and sanitary problems owing to its rapid dissemination. However, the development of antivirals against ZIKV is lagging. Although various strategies have been used to study anti-ZIKV agents, approved drugs or vaccines for the treatment (or prevention) of ZIKV infections are currently unavailable. Repurposing clinically approved drugs could be an effective approach to quickly respond to an emergency outbreak of ZIKV infections. The well-established safety profiles and optimal dosage of these clinically approved drugs could provide an economical, safe, and efficacious approach to address ZIKV infections. This review focuses on the recent research and development of agents against ZIKV infection by repurposing clinical drugs. Their characteristics, targets, and potential use in anti-ZIKV therapy are presented. This review provides an update and some successful strategies in the search for anti-ZIKV agents are given.
Adult ; Animals ; Drug Repositioning ; Humans ; Infant, Newborn ; Microcephaly ; Pharmaceutical Preparations ; Zika Virus ; Zika Virus Infection/prevention & control*

We report the diagnosis and treatment of a neonate with primary pulmonary hypertension. The full-term baby was delivered vaginally in good condition at birth and admitted eight days after birth due to intermittent cyanosis. The chest X-ray showed a scattered sheet-like shadow in both lungs, and the cardiac color doppler studies suggested patent ductus arteriosus. Following admission, the neonate was given three days of anti-infection and headbox oxygen treatment. Despite subsequent high-frequency ventilator assisted ventilation combined with nitric oxide inhalation and continuous intravenous milrinone and oral sildenafil, the baby's condition worsened, and she died fifteen minutes after withdrawing resuscitation. Genetic studies revealed a chr13:37446983 mutation in SMAD9.