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 establish the structural confirmation methods of three suspected new psychoac-tive substances(NPSs),and explore a more general qualitative testing method.Methods Infrared ab-sorption spectroscopy(IR),gas chromatography-mass spectrometry(GC-MS),1H-nuclear magnetic reso-nance spectroscopy(1H-NMR),13C-nuclear magnetic resonance spectroscopy(13C-NMR),19F-nuclear magnetic resonance spectroscopy(19F-NMR)and other techniques were used to identify the composi-tion and structure of 5 samples containing suspected NPS submitted by public security bureaus.Results NPSs were found in the above 5 samples,and 3 were confirmed as NPS included in the newly listed controlled substances on July 1,2024,namely 2-(methylamino)-2-(2-methylphenyl)cyclohexan-1-one(2-MDCK),2-(ethylamino)-2-(2-fluorophenyl)cyclohexan-l-one(2-FXE),1-(3,4-methylenedioxy-phenyl)-2-(dimethylamino)pentan-1-one(dipentylone),respectively.The first two substances were phen-cyclidine NPS,and the third substance was synthetic cathinone NPS.Conclusion This study systemati-cally summarizes the distinguishing features of the infrared absorption spectrometry,nuclear magnetic resonance spectroscopy and mass spectrometry of three NPSs,which can provide a reference for the qualitative identification of unknown substances.

Mytilus is one of bivalves with great economic and ecological values.The innate immune de-fense of Mytilus shows great significance in the study of marine biological immunology.Hemolymph is the main immune tissue for Mytilus.The Nanopore full-length transcriptome of Mytilus coruscus hemocytes,and the serum differential proteomics based on SDS-PAGE analysis were performed to identify key pro-teins involving in the immune response of Mytilus hemolymph in response of different bacteria and fungi stresses.A total of 44 proteins were identified in the serum induced by different microorganisms.Among them,26 proteins showed significant differential expression level in response to different microbial stres-ses,and their functions were involved in protein folding protection,cell autophagy and apoptosis regula-tion,reactive oxygen species production,energy metabolism regulation,cell detoxification,and immune regulation.The changes in expression levels of these proteins varied in response to different bacterial and fungal stresses,suggesting that Mytilus has different immune response strategies to different bacterial and fungal stresses.The results provide a new scientific basis for understanding the differential immune mech-anism of Mytilus innate immune system in response to different types of microbial invasion,as well as the screening of specific biomarker proteins for microbial infection,and provide ideas for the healthy develop-ment and disease prevention of shellfish aquaculture.

OBJECTIVE: Clinical characteristics and outcome in COVID-19 with brucellosis patients has not been well demonstrated, we tried to analyze clinical outcome in local and literature COVID-19 cases with brucellosis before and after recovery. METHODS: We retrospectively collected hospitalization data of comorbid patients and prospectively followed up after discharge in Heilongjiang Infectious Disease Hospital from January 15, 2020 to April 29, 2022. Demographics, epidemiological, clinical symptoms, radiological and laboratory data, treatment medicines and outcomes, and follow up were analyzed, and findings of a systematic review were demonstrated. RESULTS: A total of four COVID-19 with brucellosis patients were included. One patient had active brucellosis before covid and 3 patients had nonactive brucellosis before brucellosis. The median age was 54.5 years, and all were males (100.0%). Two cases (50.0%) were moderate, and one was mild and asymptomatic, respectively. Three cases (75.0%) had at least one comorbidity (brucellosis excluded). All 4 patients were found in COVID-19 nucleic acid screening. Case C and D had only headache and fever on admission, respectively. Four cases were treated with Traditional Chinese medicine, western medicines for three cases, no adverse reaction occurred during hospitalization. All patients were cured and discharged. Moreover, one case (25.0%) had still active brucellosis without re-positive COVID-19, and other three cases (75.0%) have no symptoms of discomfort except one case fell fatigue and anxious during the follow-up period after recovery. Conducting the literature review, two similar cases have been reported in two case reports, and were both recovered, whereas, no data of follow up after recovery. CONCLUSION These cases indicate that COVID-19 patients with brucellosis had favorable outcome before and after recovery. More clinical studies should be conducted to confirm our findings.
Female ; Humans ; Male ; Middle Aged ; Brucellosis ; COVID-19 ; Retrospective Studies ; SARS-CoV-2 ; Treatment Outcome ; Case Reports as Topic

BACKGROUND: It is not clear whether sacubitril/valsartan is beneficial for patients with heart failure (HF) with reduced ejection fraction (HFrEF) and low systolic blood pressure (SBP). This study aimed to investigate the efficacy and tolerability of sacubitril/valsartan in HFrEF patients with SBP < 100 mmHg. METHODS & RESULTS: An observational study was conducted on 117 patients, 40.2% of whom had SBP < 100 mmHg without symptomatic hypotension, and 59.8% of whom had SBP ≥ 100 mmHg in an optimized HF follow-up management system. At the 6-month follow-up, 52.4% of patients with SBP < 100 mmHg and 70.0% of those with SBP ≥ 100 mmHg successfully reached the target dosages of sacubitril/valsartan. A reduction in the concentration of N-terminal pro-B-type natriuretic peptide was similar between patients with SBP < 100 mmHg and SBP ≥ 100 mmHg (1627.5 pg/mL and 1340.1 pg/mL, respectively; P = 0.75). The effect of sacubitril/valsartan on left ventricular ejection fraction was observed in both SBP categories, with a 10.8% increase in patients with SBP < 100 mmHg (P < 0.001) and a 14.0% increase in patients with SBP ≥ 100 mmHg (P < 0.001). The effects of sacubitril/valsartan on SBP were statistically significant and inverse across both SBP categories (P = 0.001), with an increase of 7.5 mmHg in patients with SBP < 100 mmHg and a decrease of 11.5 mmHg in patients with SBP ≥ 100 mmHg. No statistically significant differences were observed between the two groups in terms of the occurrence of symptomatic hypotension, deteriorating renal function, hyperkalemia, angioedema, or stroke. CONCLUSIONS Within an optimized HF follow-up management system, sacubitril/valsartan exhibited excellent tolerability and prompted left ventricular reverse remodeling in patients with HFrEF who presented asymptomatic hypotension.

Humans ; Bridged Bicyclo Compounds, Heterocyclic/therapeutic use* ; Hydrazines/therapeutic use* ; Leukemia, Myeloid, Acute/drug therapy*

Objective:To systematically review the impact of Chinese centralized volume-based procurement(VBP)policy on the pharmaceutical industry.Methods:Relevant literature published between January 1,2019 and July 31,2023 were retrieved from the database of CNKI,WanFang data,PubMed,and Web of Science.A thematic analysis framework was constructed for data collation and analysis applying the Structure-Conduct-Performance(SCP)paradigm.Results:Forty-one studies were included,with 10(24.4%),24(58.5%),and 23(56.1%)reporting the dimension of structure,conduct,and performance,covering 10 secondary themes.Literature shows that,in terms of market structure,the market share of bid-winning enterprises increased after VBP policy,and the concentration ratio of pharmaceutical industry promoted;as for enterprise conduct,the R&D investment of both bid-winning and bid-non-winning enterprises increased under policy implementation,and the selling expenses on policy-covered products significantly reduced while policy-uncovered products did not;as for industry performance,the impact of VBP policy on operational performance varies among enterprise,and the initially positive effect on promoting innovative output of bid-winning enterprises was observed.Conclusions:The VBP policy has shown positive effects in optimizing market structure,guiding enterprise conduct,and improving industry performance.To consolidate and expand policy effects,it is recommended to further strengthen the comprehensive management of drug prices,expand the boundaries of the VBP market,and strengthen policy monitoring and tracking research.

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.
Female ; Fetal Growth Retardation ; Gestational Age ; Hospitalization ; Humans ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Prospective Studies ; Risk Factors

IL-34 can promote osteoclast differentiation and activation, which may contribute to steroidinduced osteonecrosis of the femoral head (ONFH). Animal model was constructed in both BALB/c and IL-34 deficient mice to detect the relative expression of inflammation cytokines. Micro-CT was utilized to reveal the internal structure. In vitro differentiated osteoclast was induced by culturing bone marrow-derived macrophages with IL-34 conditioned medium or M-CSF. The relative expression of pro-inflammation cytokines, osteoclast marker genes, and relevant pathways molecules was detected with quantitative real-time RT-PCR, ELISA, and Western blot. Up-regulated IL-34 expression could be detected in the serum of ONFH patients and femoral heads of ONFH mice. IL-34 deficient mice showed the resistance to ONFH induction with the up-regulated trabecular number, trabecular thickness, bone value fraction, and down-regulated trabecular separation. On the other hand, inflammatory cytokines, such as TNF-α, IFN-γ, IL-6, IL-12, IL-2, and IL-17A, showed diminished expression in IL-34 deficient ONFH induced mice. IL-34 alone or works in coordination with M-CSF to promote osteoclastogenesis and activate ERK, STAT3, and non-canonical NF-κB pathways. These data demonstrate that IL-34 can promote the differentiation of osteoclast through ERK, STAT3, and non-canonical NF-κB pathways to aggravate steroid-induced ONFH, and IL-34 can be considered as a treatment target.

OBJECTIVE: To investigate the effect of suppressing high-mobility group box 1 (HMGB1) on neuronal autophagy and apoptosis in rats after intracerebral hemorrhage (ICH) in rats. METHODS: Rat models of ICH induced by intracerebral striatum injection of 0.2 U/mL collagenase Ⅳ were treated with 1 mg/kg anti-HMGB1 mAb or a control anti-IgG mAb injected via the tail immediately and at 6 h after the operation (n=5). The rats in the sham-operated group (with intracranial injection of 2 μL normal saline) and ICH model group (n=5) were treated with PBS in the same manner after the operation. The neurological deficits of the rats were evaluated using modified neurological severity score (mNSS). TUNEL staining was used to detect apoptosis of the striatal neurons, and the expressions of HMGB1, autophagy-related proteins (Beclin-1, LC3-Ⅱ and LC3-Ⅰ) and apoptosis-related proteins (Bcl-2, Bax and cleaved caspase-3) in the brain tissues surrounding the hematoma were detected using Western blotting. The expression of HMGB1 in the striatum was detected by immunohistochemistry, and serum level of HMGB1 was detected with ELISA. RESULTS: The rat models of ICH showed significantly increased mNSS (P < 0.05), which was markedly lowered after treatment with anti- HMGB1 mAb (P < 0.05). ICH caused a significant increase of apoptosis of the striatal neurons (P < 0.05), enhanced the expressions of beclin-1, LC3-Ⅱ, Bax and cleaved caspase-3 (P < 0.05), lowered the expressions of LC3-Ⅰ and Bcl-2 (P < 0.05), and increased the content of HMGB1 (P < 0.05). Treatment with anti-HMGB1 mAb obviously lowered the apoptosis rate of the striatal neurons (P < 0.05), decreased the expressions of Beclin-1, LC3-Ⅱ, Bax and cleaved caspase-3 (P < 0.05), increased the expressions of LC3-Ⅰ and Bcl-2 (P < 0.05), and reduced the content of HMGB1 in ICH rats (P < 0.05). CONCLUSION Down- regulation of HMGB1 by anti-HMGB1 improves neurological functions of rats after ICH possibly by inhibiting autophagy and apoptosis of the neurons.
Animals ; Apoptosis ; Apoptosis Regulatory Proteins/metabolism* ; Autophagy ; Beclin-1 ; Caspase 3/metabolism* ; Cerebral Hemorrhage/therapy* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein/metabolism*