Penicillin G acylases (PGAs) are industrially important enzymes primarily used for the synthesis of first- and second-generation cephalosporins or penicillins. This study aims to establish a high-efficiency biosynthetic system for cefradine on the purpose of significantly enhancing its catalytic efficiency in cefradine synthesis and developing its potentials for industrial application. In this study, we identified and engineered penicillin G acylase and obtained a highly active mutant KsPGA M7(M168F/F313G) for the synthesis of cefradine. The mutant achieved a conversion rate over 95% in the scaled-up reaction. To validate its industrial applicability, we immobilized both the wild-type and mutant enzymes and applied them in continuous flow reactions, which achieved a space-time yield of 2 800 g/(L·d). This study lays a foundation for the future applications of penicillin G acylases in the industrial synthesis of cefradine.
Penicillin Amidase/biosynthesis* ; Protein Engineering/methods* ; Cephradine/metabolism* ; Escherichia coli/metabolism* ; Enzymes, Immobilized/metabolism* ; Recombinant Proteins/biosynthesis*

Lung cancer is a major cause of cancer-related mortality worldwide. Among patients with non-small cell lung cancer (NSCLC), approximately 3%-7% harbor anaplastic lymphoma kinase (ALK) gene fusions. In recent years, multiple tyrosine kinase inhibitors (TKIs) have significantly improved the survival of patients with metastatic ALK-positive NSCLC. However, disease progression due to resistance remains a challenge. This article retrospectively analyzes a case of advanced lung adenocarcinoma with the echinoderm microtubule associated protein like 4 (EML4)-ALK fusion variant 3 (V3). The patient developed resistance to Lorlatinib treatment accompanied by mesenchymal-epithelial transition factor (MET) amplification. Effective tumor control was achieved with the combined use of Crizotinib and Lorlatinib, providing a valuable reference for further exploration of treatment strategies following resistance to ALK-TKIs in clinical practice.
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Humans ; Adenocarcinoma/genetics* ; Adenocarcinoma of Lung/genetics* ; Aminopyridines/therapeutic use* ; Crizotinib/therapeutic use* ; Drug Resistance, Neoplasm/drug effects* ; Lactams/therapeutic use* ; Lung Neoplasms/genetics* ; Oncogene Proteins, Fusion/metabolism* ; Protein Kinase Inhibitors/therapeutic use* ; Proto-Oncogene Proteins c-met/metabolism* ; Pyrazoles/therapeutic use*

The coronavirus disease 2019 (COVID-19) pandemic has stimulated tremendous efforts to develop therapeutic agents that target severe acute respiratory syndrome coronavirus 2 to control viral infection. So far, a few small-molecule antiviral drugs, including nirmatrelvir-ritonavir (Paxlovid), remdesivir, and molnupiravir have been marketed for the treatment of COVID-19. Nirmatrelvir-ritonavir has been recommended by the World Health Organization as an early treatment for outpatients with mild-to-moderate COVID-19. However, the existing treatment options have limitations, and effective treatment strategies that are cost-effective and convenient for tackling COVID-19 are still needed. To date, four domestically developed oral anti-COVID-19 drugs have been granted conditional market approval in China. These drugs include azvudine, simnotrelvir-ritonavir (Xiannuoxin), leritrelvir, and mindeudesivir (VV116). Preclinical and clinical studies have explored the efficacy and tolerability of mindeudesivir and supported its early use in mild-to-moderate COVID-19 cases at high risk for progression. In this review, we discuss the most recent findings regarding the pharmacological mechanism and therapeutic effects focusing on mindeudesivir and other small-molecule antiviral agents for COVID-19. These findings will expand our understanding and highlight the potential widespread application of China's homegrown anti-COVID-19 drugs.
Humans ; Ritonavir/therapeutic use* ; COVID-19 ; Antiviral Agents/therapeutic use* ; China ; Nitriles ; Lactams ; Proline ; Adenosine/analogs & derivatives* ; Leucine

Objective: To investigate the clinical characteristics, serogroups and antimicrobial resistance of invasive non-typhoid Salmonella infection in children at Xiamen. Methods: Retrospective cohort study. The clinical manifestations, treatment, prognosis, serogroups and antimicrobial resistance of 29 hospitalized children with invasive non-typhoid Salmonella infection confirmed by blood, cerebrospinal fluid, bone marrow and other sterile body fluids or deep pus culture at the Department of Infectious Diseases, the Department of Orthopedics and the Department of General Surgery in Xiamen Children's Hospital from January 2016 to December 2021 were analyzed. According to the clinical diagnosis criteria, the patients were divided into sepsis group and non-sepsis group (bacteremia and local suppurative infection). The inflammatory markers, serogroups distribution and drug resistance were compared between the two groups. Comparison between groups using Mann-Whitney U test and χ² test. Results: Among the 29 cases, there were 17 males and 12 females, with an onset age of 14 (9, 25) months, and 10 cases (34%) of patients were younger than 1 year old, 15 cases (52%) under 1 to 3 years old, and 4 cases (14%) greater than or equal 3 years old. The onset time of 25 cases (86%) was from April to September. The diseases included 19 cases (66%) septicemia (2 of which were combined with suppurative meningitis), 10 cases (34%) non-sepsis group, including 7 cases bacteremia and 3 cases local suppurative infection (2 cases of osteomyelitis, 1 case of appendicitis with peritonitis). The clinical manifestations were fever in 29 cases (100%), diarrhea and abdominal pain in 18 cases (62%), cough and runny nose in 10 cases (34%). Eighteen cases (62%) were cured and 11 cases (38%) were improved by effective antibiotics treatment. C-reactive protein in sepsis group was significantly higher than that in non-sepsis group (25.2 (16.1, 56.4) vs. 3.4 (0.5, 7.5) mg/L, Z=-3.81, P<0.001).The serogroups of C, B and E were the most prevalent among non-typhoid Salmonella isolates, accounting for 10 cases (34%), 9 cases (31%) and 7 cases (24%) respectively. Antibacterial drug sensitivity test showed that the sensitivity rates of imipenem, ertapenem and piperaciratazobactam were all 100% (31/31), those of ceftazidime, ceftriaxone, and cefepime were 94% (29/31), 94% (29/31) and 97% (30/31) respectively. The drug resistance rates of ampicillin, ampicillin-sulbactam and trimethoprim-sulfamethoxazole were 51% (16/31), 48% (15/31) and 48% (15/31) respectively, those of cefazolin, cefotetan, tobramycin, gentamicin and amikacinwere all 100% (31/31). There were no significant differences in the drug resistance rates of ceftazidime, ceftriaxone, aztreonam, ampicillin-sulbactam, ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin between the sepsis group and the non-sepsis group (χ²=0.31,0.31,0.00,0.02,0.02,0.02,0.26, all P>0.05). Conclusions: Invasive non-typhoid Salmonella infection in children at Xiamen mainly occurred in infants younger than 3 years old.The main clinical manifestations are fever, abdominal pain and diarrhea. C-reactive protein can be served as the laboratory indicators for indicating sepsis. The third generation of cephalosporins is recommended as the first choice for treatment.
Infant ; Male ; Female ; Child ; Humans ; Child, Preschool ; Anti-Bacterial Agents/therapeutic use* ; Ceftriaxone/therapeutic use* ; Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use* ; Ceftazidime/therapeutic use* ; Retrospective Studies ; C-Reactive Protein ; Drug Resistance, Bacterial ; Salmonella Infections/microbiology* ; Ampicillin/therapeutic use* ; Salmonella ; Diarrhea/drug therapy* ; Bacteremia ; Abdominal Pain ; Microbial Sensitivity Tests

Objective: To explore the clinical characteristics, common pathogens in children with vulvovaginitis. Methods: This was a retrospective cases study. A total of 3 268 children with vulvovaginitis were enrolled, who visited the Department of Pediatric and Adolescent Gynecology, Children's Hospital, Zhejiang University School of Medicine from January 2009 to December 2019. Patients were divided into 3 groups according to the age of <7, 7-<10 and 10-18 years. Patients were also divided in to 4 groups according to the season of first visit. The pathogen distribution characteristics of infective vulvovaginitis were compared between the groups. Their clinical data were collected and then analyzed by χ² test. Results: The were 3 268 girls aged (6.2±2.5) years. There were 1 728 cases (52.9%) aged <7 years, 875 cases (26.8%) aged 7-<10 years, and 665 cases (20.3%) aged 10-18 years. Of these cases, 2 253 cases (68.9%) were bacterial vulvovaginitis, 715 cases (21.9%) were fungal vulvovaginitis and 300 cases (9.2%) were vulvovaginitis infected with other pathogens. Bacterial culture of vaginal secretions was performed in 2 287 cases, and 2 287 strains (70.0%) of pathogens were detected, of which the top 5 pathogens were Streptococcus pyogenes (745 strains, 32.6%), Haemophilus influenzae (717 strains, 31.4%), Escherichia coli (292 strains, 12.8%), Staphylococcus aureus (222 strains, 9.7%) and Klebsiella pneumoniae (67 strains, 2.9%). Regarding different age groups, H.influenzae was the most common in children under 7 years of age (40.3%, 509/1 263), S.pyogenes (41.9%, 356/849) was predominantly in children aged 7 to 10 years, and E.coli was predominant in children aged 10 to 18 years (26.3%, 46/175). Susceptibility results showed that S.pyogenes was susceptible to penicillin G (610/610, 100.0%), ceftriaxone (525/525, 100.0%), and vancomycin (610/610, 100.0%); the resistance rates to erythromycin and clindamycin were 91.9% (501/545)and 90.7% (495/546), respectively. For H.influenzae, 32.5% (161/496) produced β-elactamase, and all strains were sensitive to meropenem (489/489, 100.0%) and levofloxacin (388/388, 100.0%), while 40.5% (202/499) were resistant to ampicillin. Among E.coli, all strains were sensitive to imipenem(100%, 175/175). The resistance rates of E.coli to levofloxacin and ceftriaxone were 29.1% (43/148) and 35.1% (59/168), respectively. A total of 48 strains of methicillin-resistant Staphylococcus aureus (MRSA) were isolated with a proportion of 28.3% (45/159) in 3 268 patients. The results of drug susceptibility test showed that all MRSA strains were sensitive to linezolid 100.0% (40/40), vancomycin (45/45, 100.0%), and tigecycline (36/36, 100.0%); the resistance rates of MRSA to penicillin G, erythromycin and clindamycin were 100% (45/45), 95.6% (43/45) and 88.9% (40/45), respectively. All methicillin-sensitive Staphylococcus aureus (MSSA) strains were sensitive to oxacillin (114/114, 100.0%), linezolid (94/94, 100.0%), vancomycin (114/114, 100.0%), and tigecycline (84/84, 100.0%); it's resistance rates to penicillin G, erythromycin and clindamycin were 78.1% (89/114), 59.7% (68/114) and 46.5% (53/114), respectively. The drug resistance rate of MSSA to penicillin G, erythromycin and clindamycin were lower than those of MRSA (χ²=11.71,19.74,23.95, respectively, all P<0.001). Conclusions: The age of consultation for pediatric infectious vulvovaginitis is mainly around 6 years. The most common pathogens are S.pyogenes, H.influenzae and Escherichia coli. Third generation cephalosporins can be used as the first choice of empirical anti-infection drugs. However, the results of drug susceptibility should be considered for targeted treatment.
Female ; Adolescent ; Child ; Humans ; Anti-Bacterial Agents/therapeutic use* ; Vancomycin/therapeutic use* ; Methicillin-Resistant Staphylococcus aureus ; Clindamycin/therapeutic use* ; Ceftriaxone/therapeutic use* ; Tigecycline/therapeutic use* ; Linezolid/therapeutic use* ; Levofloxacin/therapeutic use* ; Retrospective Studies ; Microbial Sensitivity Tests ; Staphylococcus aureus ; Staphylococcal Infections/drug therapy* ; Erythromycin/therapeutic use* ; Methicillin ; Penicillin G/therapeutic use* ; Escherichia coli ; Drug Resistance, Bacterial

OBJECTIVE: To analyze the distribution and drug resistance of pathogens in oral mucositis associated with chemotherapy in hospitalized patients with malignant hematopathy, so as to provide scientific evidences for rational selection of antibiotics and infection prevention and control. METHODS: From July 2020 to June 2022, 167 patients with malignant hematopathy were treated with chemical drugs in the Department of Hematology, Hainan Hospital, and secretions from oral mucosal infected wounds were collected. VITEK2 COMPECT automatic microbial identification system (BioMerieux, France) and bacterial susceptibility card (BioMerieux) were used for bacterial identification and drug susceptibility tests. RESULTS: A total of 352 strains of pathogens were isolated from 167 patients, among which 220 strains of Gram-positive bacteria, 118 strains of Gram-negative bacteria and 14 strains of fungi, accounted for 62.50%, 33.52% and 3.98%, respectively. The Gram-positive bacteria was mainly Staphylococcus and Streptococcus, while Gram-negative bacteria was mainly Klebsiella and Proteus. The resistance of main Gram-positive bacteria to vancomycin, ciprofloxacin and gentamicin was low, and the resistance to penicillin, cefuroxime, ampicillin, cefotaxime, erythromycin and levofloxacin was high. The main Gram-negative bacteria had low resistance to gentamicin, imipenem and penicillin, but high resistance to levofloxacin, cefotaxime, cefuroxime, ampicillin and vancomycin. The clinical data of oral mucositis patients with oral ulcer (severe) and without oral ulcer (mild) were compared, and it was found that there were statistically significant differences in poor oral hygiene, diabetes, sleep duration less than 8 hours per night between two groups (P<0.05). CONCLUSION Gram-positive bacteria is the main pathogen of oral mucositis in patients with malignant hematopathy after chemotherapy. It is sensitive to glycopeptide antibiotics and aminoglycosides antibiotics. Poor oral hygiene, diabetes and sleep duration less than 8 hours per night are risk factors for oral mucositis with oral ulcer (severe).
Humans ; Vancomycin/therapeutic use* ; Cefuroxime ; Levofloxacin ; Oral Ulcer/drug therapy* ; Drug Resistance, Bacterial ; Anti-Bacterial Agents/adverse effects* ; Ampicillin ; Penicillins ; Cefotaxime ; Gram-Positive Bacteria ; Gram-Negative Bacteria ; Gentamicins ; Stomatitis/drug therapy*

INTRODUCTION: Drug allergies are often self-reported but of unknown accuracy. We carried out a prospective study to examine the utility and safety of formal allergology evaluation, and to identify factors associated with accurate drug allergy labels. METHOD: All patients who underwent drug allergy evaluation in our clinic during the study period were recruited. Baseline demographics, characteristics of index hypersensitivity reaction and outcomes of evaluation were recorded. RESULTS: A total of 331 patients from March 2019 to June 2021 completed drug allergy evaluation to index drugs of concern. There were 123 (37%) male patients, and the mean age was 49 years (standard deviation 17). There were 170 beta-lactam antibiotics, 53 peri-operative drugs, 43 others, 38 non steroidal anti-inflammatory drugs, and 27 non-beta-lactam antibiotic evaluations. Index reaction occurred within 5 years in 165 (50%) patients, with latency of less than 4 hours in 125 (38%) patients. The most common index reactions were rash, angioedema and urticaria. There were 57 (17%) evaluations stratified as low risk, 222 (67%) moderate risk, and 52 (16%) high risk based on multidisciplinary consensus. Allergy label was found to be false (negative drug evaluation) in 248 (75%) patients, while 16/237 (7%) skin tests, 44/331 (13%) in-clinic graded challenge, and 23/134 (17%) home prolonged challenges were positive (true drug allergy). The most common evaluation reactions were rash and urticaria. No cases of anaphylaxis were elicited. CONCLUSION Seventy-five percent of drug allergy labels are inaccurate. Risk-stratified, protocolised allergy evaluation is safe. Prolonged drug challenge increases the sensitivity of drug allergy evaluation and should therefore be performed when indicated.
Humans ; Male ; Middle Aged ; Female ; Prospective Studies ; Drug Hypersensitivity/epidemiology* ; Exanthema ; Urticaria ; Monobactams

Anaplastic lymphoma kinase (ALK) fusions represent the second most common oncogenic driver mutation in non-small cell lung cancer (NSCLC). As the new class of 3rd generation of ALK tyrosine kinase inhibitor (TKI), lorlatinib has shown robust potency and brain-penetrant clinical activity against a wide spectrum of multiple resistance mutations within the ALK domain detected during crizotinib and 2nd generation ALK TKI treatment. Lorlatinib is generally well-tolerated with unique adverse drug reaction/adverse event, including hyperlipidemia and central nervous system effects, which are mostly mild to moderate severity and manageable through dosage modifications and/or standard medical intervention. For advanced NSCLC with ALK positivity, patients should be evaluated for baseline characteristics and pre-existing medication, informed of the potential toxicities, and periodically monitored to balance benefits and risks. Moreover, a multidisciplinary group of experts is essential to establish a comprehensive diagnostic and therapeutic strategy.
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Aminopyridines ; Carcinoma, Non-Small-Cell Lung/pathology* ; China ; Consensus ; Drug Resistance, Neoplasm/genetics* ; Drug-Related Side Effects and Adverse Reactions/drug therapy* ; Humans ; Lactams ; Lactams, Macrocyclic/adverse effects* ; Lung Neoplasms/pathology* ; Protein Kinase Inhibitors/adverse effects* ; Protein-Tyrosine Kinases/genetics* ; Pyrazoles

Antiviral Agents/pharmacology* ; COVID-19 ; Coronavirus 3C Proteases ; Humans ; Lactams ; Leucine ; Molecular Docking Simulation ; Molecular Dynamics Simulation ; Nitriles ; Proline ; Protease Inhibitors/pharmacology* ; SARS-CoV-2

Objective: To investigate the molecular characteristics of ciprofloxacin-cefotaxime-azithromycin co-resistant Salmonella enterica serovar Thompson (S. Thompson) isolates from sporadic cases of foodborne diseases and aquatic foods in Hunan province. Methods: Ciprofloxacin-cefotaxime-azithromycin co-resistant S. Thompson isolates were selected from samples, and broth microdilution method was used to determine the resistance to 11 antibiotics of these isolates in vitro. Whole genome sequencing was used for investigating antimicrobial resistance gene patterns and phylogenetic relationships of strains. Results: Nine ciprofloxacin-cefotaxime-azithromycin co-resistant isolates were recovered from 19 S. Thompson isolates. Among nine ciprofloxacin-cefotaxime-azithromycin co-resistant isolates, eight of them harbored IncC plasmids, simultaneously carrying plasmid-mediated quinolone resistance (PMQR) genes qepA and qnrS1, β-lactamase resistance gene bla_CMY-2, azithromycin resistance gene mph(A), and one isolate harbored IncR plasmid, and carried PMQR genes qnrB4 and aac(6')-Ib-cr, bla_OXA-10 and mph(A). Genetic environment analysis showed that qnrS1, qepA, mph(A) and bla_CMY-2 genes might be integrated on genomes of strains by ISKra4, IS91, IS6100 and ISEcp1, respectively. Phylogenetic core genome comparisons demonstrated that ciprofloxacin-cefotaxime-azithromycin co-resistant isolates from patients and aquatic foods were genetically similar and clustered together. Conclusion: Ciprofloxacin-cefotaxime-azithromycin co-resistant S. Thompson isolates have been isolated from both human and aquatic food samples, suggesting that the spread of multidrug resistant Salmonella between human and aquatic animals.
Animals ; Humans ; Ciprofloxacin ; Cefotaxime ; Azithromycin ; Serogroup ; Phylogeny ; Drug Resistance, Multiple, Bacterial/genetics* ; Anti-Bacterial Agents/pharmacology* ; Salmonella ; Quinolones ; Foodborne Diseases ; Plasmids ; Salmonella enterica ; Microbial Sensitivity Tests