As the number of patients with compromised immune function increases and fungal resistance develops, so does the risk of contracting deadly fungi in humans. Both fungi and humans are eukaryotes, so identifying unique targets for antifungal drug development is difficult. In addition, the existing antifungal drugs are limited by toxicity, drug interaction and drug resistance in practical application, which leads to the increasing incidence and fatal rate of fungal infections. Therefore, it is urgent to develop new antifungal drugs. The semi-synthetic technology using microbial fermentation products from natural sources as lead compounds has become the most used method in structural modification of antifungal drugs due to its advantages of few reaction steps and easy operation. This paper will introduce the current status of natural antifungal drugs in clinical use, as well as the latest progress in the research and development of new semi-synthetic antifungal drugs, and summarize their mechanism of action, structural modifications, advantages and disadvantages, so as to provide reference for the subsequent development of new antifungal drugs.

A derivatizaton method combined with gas chromatography-mass spectrometry(GC-MS)was established for detection of isobutyl chloroformate(IBCF)residue in active pharmaceutical ingredient of agatroban.The extraction and derivatization reagents,derivatization time,qualitative and quantitative ions were selected and optimized,respectively.The possible mechanism of derivatization and characteristic fragment ions fragmentation were speculated.The agatroban samples were dissolved and extracted by methanol,and the residual IBCF was derived with methanol to generate methyl isobutyl carbonate(MIBCB).After 24 h static derivatization at room temperature,IBCF was completely transformed into MIBCB,which could be used to indirectly detect IBCF accurately.The results showed that the linearity of this method was good in the range of 25-500 ng/mL(R2=0.9999).The limit of detection(LOD,S/N=3)was 0.75 μg/g,and the limit of quantification(LOQ,S/N=10)was 2.50 μg/g.Good recoveries(95.2%-97.8%)and relative standard deviations(RSDs)less than 3.1%(n=6)were obtained from agatroban samples at three spiked levels of IBCF(2.50,25.00,50.00 μg/g),which showed good accuracy of this method.Good precision of detection results was obtained by different laboratory technicians at different times,the mean value of spiked sample solution(25.00 μg/g)was 24.28 μg/g,and the RSD was 2.1%(n=12).The durability was good,minor changes of detection conditions had little effect on the results.Under the original condition and conditions with initial column temperature±5℃,heating rate±2℃/min,column flow rate±0.1 mL/min,the IBCF content of spiked sample solution(25.00 μg/g)was detected,the mean value of detection results was 24.16 μg/g,and the RSD was 2.2%(n=7).Eight batches of agatroban samples from two manufacturers were detected using the established method,and the results showed that no IBCF residue was detected in any of these samples.The agatroban samples could be dissolved by methanol,and then the IBCF residue could be simultaneously extracted and derived with methanol as well.This detection method had the advantages of simple operation,high sensitivity,low matrix effect and accurate quantification,which provided a new effective method for detection of IBCF residue in agatroban.

Objective:To investigate the clinical features and therapeutic efficacy of patients with hereditary leiomyomatosis and renal cell carcinoma(RCC) syndrome-associated RCC (HLRCC-RCC) in China.Methods:The clinical data of 119 HLRCC-RCC patients with fumarate hydratase (FH) germline mutation confirmed by genetic diagnosis from 15 medical centers nationwide from January 2008 to December 2021 were retrospectively analyzed. Among them, 73 were male and 46 were female. The median age was 38(13, 74) years. The median tumor diameter was 6.5 (1.0, 20.5) cm. There were 38 cases (31.9%) in stage Ⅰ-Ⅱand 81 cases (68.1%) in stage Ⅲ-Ⅳ. In this group, only 11 of 119 HLRCC-RCC patients presented with skin smooth muscle tumors, and 44 of 46 female HLRCC-RCC patients had a history of uterine fibroids. The pathological characteristics, treatment methods, prognosis and survival of the patients were summarized.Results:A total of 86 patients underwent surgical treatment, including 70 cases of radical nephrectomy, 5 cases of partial nephrectomy, and 11 cases of reductive nephrectomy. The other 33 patients with newly diagnosed metastasis underwent renal puncture biopsy. The results of genetic testing showed that 94 patients had FH gene point mutation, 18 had FH gene insertion/deletion mutation, 4 had FH gene splicing mutation, 2 had FH gene large fragment deletion and 1 had FH gene copy number mutation. Immunohistochemical staining showed strong 2-succinocysteine (2-SC) positive and FH negative in 113 patients. A total of 102 patients received systematic treatment, including 44 newly diagnosed patients with metastasis and 58 patients with postoperative metastasis. Among them, 33 patients were treated with tyrosine kinase inhibitor (TKI) combined with immune checkpoint inhibitor (ICI), 8 patients were treated with bevacizumab combined with erlotinib, and 61 patients were treated with TKI monotherapy. Survival analysis showed that the median progression-free survival (PFS) of TKI combined with ICI was 18 (5, 38) months, and the median overall survival (OS) was not reached. The median PFS and OS were 12 (5, 14) months and 30 (10, 32) months in the bevacizumab combined with erlotinib treatment group, respectively. The median PFS and OS were 10 (3, 64) months and 44 (10, 74) months in the TKI monotherapy group, respectively. PFS ( P=0.009) and OS ( P=0.006) in TKI combined with ICI group were better than those in bevacizumab combined with erlotinib group. The median PFS ( P=0.003) and median OS ( P=0.028) in TKI combined with ICI group were better than those in TKI monotherapy group. Conclusions:HLRCC-RCC is rare but has a high degree of malignancy, poor prognosis and familial genetic characteristics. Immunohistochemical staining with strong positive 2-SC and negative FH can provide an important basis for clinical diagnosis. Genetic detection of FH gene germ line mutation can confirm the diagnosis. The preliminary study results confirmed that TKI combined with ICI had a good clinical effect, but it needs to be confirmed by the results of a large sample multi-center randomized controlled clinical study.

Lipopolysaccharides (LPS) are major outer membrane components of Gram-negative bacteria. Unlike most Gram-negative bacteria, Acinetobacter baumannii can still survive and acquire polymyxin resistance after complete loss of LPS. Previous studies of LPS-deficient Acinetobacter baumannii mostly focused on LPS-deficient strains induced by polymyxin, whose background was complex and unstable. To investigate LPS loss-mediated polymyxin resistant-Acinetobacter baumannii, this study constructed a stable and clear background LPS-deficient strain by knocking out lpxC gene in Acinetobacter baumannii ATCC 19606 with CIRSPR/Cas9, and then studied the phenotypic changes of the lpxC-deficient strain including morphology, growth rate, antibiotic susceptibility, virulence, membrane permeability, and membrane potential. Animal experiments were approved by the Animal Care and Welfare Committee Institute of Medicinal Biotechnology, CAMS and PUMC (approval number: IMB-20240119D₉). The results indicated that the lpxC gene of Acinetobacter baumannii ATCC 19606 was successfully knocked out. After losing the lpxC, the strain underwent the morphological change from rod-shaped to spherical. Furthermore, it leads to reduced growth rate, enhanced membrane permeability, decreased membrane potential, lower virulence, and increased antibiotic susceptibility to β-lactams, quinolones, aminoglycosides, macrolides, glycopeptides. The lpxC deletion results in significant changes in membrane homeostasis and adaptability of Acinetobacter baumannii. Understanding the phenotypic changes of colistin-resistant Acinetobacter baumannii mediated by LPS loss is useful for exploring the resistance mechanism of Acinetobacter baumannii and developing new therapeutic strategies.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective:To carry out the policy diffusion analysis of centralized and volume-based drug procurement in China in recent years,and to provide reference for the formulation of centralized and volume-based drug procurement policy.Methods:Through the official websites of the central and provincial governments,the official websites of the Health Commission and the official websites of the Medical Security Bureau,the policy documents related to centralized and volume-based drug procurement from January 1,2009 to December 31,2023 were searched.Based on the policy diffusion theory,the reference network analysis method is used to analyze the intensity,breadth and speed of policy diffusion,and the sequential analysis method of policy keywords is used to analyze the direction of policy diffusion.Results:In the two stages of the development of centralized and volume-based drug procurement policy,the number of policies issued in the medical insurance management stage reached the peak;The top ten policies with the highest diffusion intensity and breadth are all central policies,and most of them are notices and opinions.In addition,the newly promulgated policies have a faster diffusion speed.In the direction of diffusion,top-down and parallel diffusion trends are obvious.Conclusion:The diffusion of centralized and volume-based drug procurement policy in China focuses on the central policy,and the diffusion speed is increasing year by year.It is suggested to strengthen the policy coordination between the central and local governments,establish a unified national information platform for centralized drug procurement,optimize the learning and competition mechanism between governments at all levels,and give play to the advantages of"policy experiment".

Objective:To investigate the efficacy and influencing factors of initial 131I therapy in serum thyroglobulin (Tg) antibody (TgAb)-positive patients with papillary thyroid cancer (PTC). Methods:A retrospective analysis was performed on the clinical data of 1 624 patients with PTC who underwent 131I therapy in Henan Provincial People′s Hospital between January 2017 and January 2023. The patients were divided into TgAb-positive group (246 cases (36 males, 210 females), age: 43.5(31.0, 52.0) years) and TgAb-negative group (1 378 cases (439 males, 939 females), age: 44.0(34.0, 53.0) years). The efficacy was evaluated 6-12 months post 131I therapy based on serological tests (TgAb, Tg) and imaging results (ultrasonography, CT, 131I-whole body scan (WBS), SPECT/CT imaging), and the patients were divided into disease persistence/recurrence and non-persistence/recurrence groups. The χ2 test was used to analyze the difference in efficacy between the TgAb-positive group and the TgAb-negative group. Among TgAb-positive patients, the clinical characteristics of disease persistence/recurrence group were compared with those of non-persistence/recurrence ones by χ2 test or Mann-Whitney U test, and the independent risk factors affecting the efficacy of 131I therapy were analyzed by binary logistic regression. Results:The disease persistence/recurrence were found in 38 cases (15.4%, 38/246) of the TgAb-positive group and 143 cases (10.4%, 143/1 378) of the TgAb-negative group, with a statistically significant difference between the two groups ( χ2=5.42, P=0.020). Among the TgAb-positive patients, statistically significant differences were found in lymph node metastasis (35 vs 23 cases), the interval between surgery and 131I therapy (2.0(1.5, 3.0) vs 2.3(2.0, 3.0) months), stimulated Tg(sTg) level before the initial 131I therapy (0.18(0.04, 5.78) vs 0.04(0.04, 0.46) μg/L), and TgAb level before the initial 131I therapy (40.15(19.13, 156.15) vs 22.25(7.53, 76.20) kU/L) between disease persistence/recurrence group and non-persistence/recurrence group ( χ2=117.13, z values: -2.29, -2.41, -2.80, all P<0.05). Lymph node metastasis was an independent risk factor (odds ratio( OR)=89.326, 95% CI: 25.005-319.106, P<0.001) for the efficacy of 131I therapy in patients with TgAb-positive PTC. Conclusion:The overall efficacy of 131I therapy in patients with TgAb-positive PTC is relatively poor, and lymph node metastasis is an independent risk factor for the efficacy of 131I therapy, while the level of TgAb is not an independent risk factor for the efficacy of 131I therapy in these patients.

Objective:To investigate the impact of ionizing radiation(IR)on the structure and function of the testis and pro-vide some strategies for the prevention and treatment of IR-induced damage(IRD).Methods:Using radiation dose simulation,se-men analysis,hormone testing,electron microscopy and single-cell transcriptome sequencing,we assessed and analyzed a case of IRD.We established a mouse model of IRD to validate the results of single-cell sequencing,and investigated the specific biological mecha-nisms of IRD and potential strategies for its intervention.Results:IR at 1-2 Gy significantly reduced sperm concentration and mo-tility,which gradually recovered after 12 months but the percentage of morphologically normal sperm remained low.It also caused im-balanced levels of various steroid hormones,decreased testosterone and dehydroepiandrosterone sulfate,increased progesterone,prolac-tin,luteinizing hormone,and follicle-stimulating hormone.Electron microscopy revealed damages to the testis structure,including loss of germ cells,atrophy of the seminiferous tubules,nuclear membrane depression of the spermatocytes,mitochondrial atrophy and de-formation,and reduction of mitochondrial cristae.Single-cell sequencing indicated significant changes in the function of the Leydig cells and macrophages and disrupted lipid-related metabolic pathways after IRD.Administration of L-carnitine to the mouse model im-proved lipid metabolism disorders and partially alleviated IRD to the germ cells.Conclusion:Ionizing radiation can cause disorders of testicular spermatogenesis and sexual hormones and inhibit lipid metabolism pathways in Leydig cells and macrophages.Improving lipid metabolism can alleviate IRD to germ cells.

Polyurethane (PUR) plastics is widely used because of its unique physical and chemical properties. However, unreasonable disposal of the vast amount of used PUR plastics has caused serious environmental pollution. The efficient degradation and utilization of used PUR plastics by means of microorganisms has become one of the current research hotspots, and efficient PUR degrading microbes are the key to the biological treatment of PUR plastics. In this study, an Impranil DLN-degrading bacteria G-11 was isolated from used PUR plastic samples collected from landfill, and its PUR-degrading characteristics were studied. Strain G-11 was identified as Amycolatopsis sp. through 16S rRNA gene sequence alignment. PUR degradation experiment showed that the weight loss rate of the commercial PUR plastics upon treatment of strain G-11 was 4.67%. Scanning electron microscope (SEM) showed that the surface structure of G-11-treated PUR plastics was destroyed with an eroded morphology. Contact angle and thermogravimetry analysis (TGA) showed that the hydrophilicity of PUR plastics increased along with decreased thermal stability upon treatment by strain G-11, which were consistent with the weight loss and morphological observation. These results indicated that strain G-11 isolated from landfill has potential application in biodegradation of waste PUR plastics.
Plastics/metabolism* ; Polyurethanes/chemistry* ; RNA, Ribosomal, 16S ; Bacteria/genetics* ; Biodegradation, Environmental

Objective To evaluate extrathyroidal extension (ETE) in papillary thyroid microcarcinoma (PTMC) with three-dimensional tomographic ultrasound imaging (3D-TUI). Methods A total of 97 thyroid nodules of 79 patients with PTMC treated in PUMC Hospital from February 2016 to January 2018 were included in this study.Two ultrasound experts performed independent blinded assessment of the relationship between thyroid nodules and thyroid capsule by two-dimensional ultrasound (2D-US) and 3D-TUI.The results of 2D-US and 3D-TUI in evaluating ETE were compared with intraoperative findings and postoperative histological and pathological results. Results Among the 97 nodules,54 (55.7%) nodules had ETE.The diagnostic sensitivity (68.5% vs.37.0%;χ²=10.737,P=0.002),accuracy (74.5% vs.56.7%;χ²=6.686,P=0.015),and area under the receiver operating characteristic curve[0.761 (95%CI=0.677-0.845) vs.0.592 (95%CI=0.504-0.680);Z=3.500,P<0.001] of 3D-TUI were higher than those of 2D-US.However,3D-TUI and 2D-US showed no significant difference in the specificity (84.1% vs.81.4%;χ²=0.081,P=0.776),negative predictive value (67.9% vs.50.7%;χ²=3.645,P=0.066),or positive predictive value (84.1% vs.71.4%;χ²=1.663,P=0.240). Conclusion Compared with 2D-US,3D-TUI demonstrates increased diagnostic efficiency for ETE of PTMC.
Humans ; Thyroid Nodule ; Thyroid Neoplasms/diagnosis* ; Carcinoma, Papillary/pathology* ; Ultrasonography/methods* ; Retrospective Studies