Objective Fasting hypometabolism regulation technology has broad application potential in long-term space flight and survival in extreme extraterrestrial environments.In-depth research on the substrate conversion of energy metabolism and the formation of new steady states under fasting hypometabolism will provide theoretical basis and experimental data support for formulating effective prolonged fasting application mode.Methods 30 SD rats were randomly divided into control group and fasting group(fasting for 1,2,3,and 5 days).Blood biochemical examination,qRT-PCR,and western blotting were performed to analyze the body weight,blood biochemistry,and expression changes of genes and proteins related to glucose and lipid metabolism during different fasting periods.Results Prolonged fasting significantly reduced the body weight,blood glucose,and triglyceride levels of rats;increased the blood ketone level,and replaced glucose as the main energy substance in the body.There are temporal and tissue-specific changes as a whole.Hepatic and renal gluconeogenesis play major roles respectively during different fasting periods.As the fasting time prolongs,the level of hepatic gluconeogenesis gradually decreases,the content of FFA in the blood increases,the expression level of genes related to fat synthesis decreases,fatty acid oxidation is enhanced,and the expression level of the key gene HMGCS2 for ketone body generation increases.Conclusion During prolonged fasting,there is a significant conversion of glucose-ketone energy supply substrates,and a new steady state of energy metabolism mainly supplied by ketone bodies is formed within 2-5 days of fasting.The body maintains a low metabolic state by regulating changes in key genes in pathways such as glucose and lipid metabolism.

OBJECTIVE To establish an HPLC fingerprint of Xiao’er resuqing oral liquid， and to determine the contents of twelve index components. METHODS HPLC method was adopted. The determination was performed on Venusil MP C18 column with mobile phase consisting of acetonitrile-0.1% phosphate aqueous solution （gradient elution） at a flow rate of 1.0 mL/min. The detection wavelength was set at 210 nm， the column temperature was 30 ℃， the injection volume was 10 μL. HPLC fingerprint of Xiao’er resuqing oral liquid was established by using the Similarity Evaluation System of Chromatographic Fingerprint of TCM （2012 edition） to evaluate the similarity. The contents of 12 components were determined， including （R， S）-goitrin， 3，5-O-dicaffeoyl quinic acid， puerarin， forsythin， forsythoside A， chlorogenic acid， baicalin， saikosaponins d， wogonoside， baicalein， emodin and chrysophanol. RESULTS The similarity of HPLC fingerprints of 13 batches of Xiao’er resuqing oral liquid was greater than 0.97， and 14 common peaks were confirmed. The contents of the above 12 index components in 13 batches of Xiao’er resuqing oral liquid were as follows： 0.078-0.172， 1.564-2.736， 1.338-2.578， 0.426-0.872， 1.477-2.628， 1.396-2.447， 4.052-9.146， 0.367- 0.692， 1.974-4.674， 1.274-2.969， 0.085-0.167 and 0.155-0.307 mg/mL. CONCLUSIONS The established HPLC fingerprint and content determination methods have high accuracy and high specificity， which can be used for the quality evaluation of Xiao’er resuqing oral liquid.

A series of new monobactam sulfonates is continuously synthesized and evaluated for their antimicrobial efficacies against Gram-negative bacteria. Compound 33a (IMBZ18G) is highly effective in vitro and in vivo against clinically intractable multi-drug-resistant (MDR) Gram-negative strains, with a highly druglike nature. The checkerboard assay reveals its significant synergistic effect with β-lactamase inhibitor avibactam, and the MIC values against MDR enterobacteria were reduced up to 4-512 folds. X-ray co-crystal and chemoproteomic assays indicate that the anti-MDR bacteria effect of 33a results from the dual inhibition of the common PBP3 and some class A and C β-lactamases. Accordingly, preclinical studies of 33a alone and 33a‒avibactam combination as potential innovative candidates are actively going on, in the treatment of β-lactamase-producing MDR Gram-negative bacterial infections.

Polymyxin B and polymyxin E (colistin) are presently considered the last line of defense against human infections caused by multidrug-resistant Gram-negative organisms such as carbapenemase-producer Enterobacterales, Acinetobacter baumannii, and Klebsiella pneumoniae. Yet resistance to this last-line drugs is a major public health threat and is rapidly increasing. Polymyxin S₂ (S₂) is a polymyxin B analogue previously synthesized in our institute with obviously high antibacterial activity and lower toxicity than polymyxin B and colistin. To predict the possible resistant mechanism of S₂ for wide clinical application, we experimentally induced bacterial resistant mutants and studied the preliminary resistance mechanisms. Mut-S, a resistant mutant of K. pneumoniae ATCC BAA-2146 (Kpn2146) induced by S₂, was analyzed by whole genome sequencing, transcriptomics, mass spectrometry and complementation experiment. Surprisingly, large-scale genomic inversion (LSGI) of approximately 1.1 Mbp in the chromosome caused by IS26 mediated intramolecular transposition was found in Mut-S, which led to mgrB truncation, lipid A modification and hence S₂ resistance. The resistance can be complemented by plasmid carrying intact mgrB. The same mechanism was also found in polymyxin B and colistin induced drug-resistant mutants of Kpn2146 (Mut-B and Mut-E, respectively). This is the first report of polymyxin resistance caused by IS26 intramolecular transposition mediated mgrB truncation in chromosome in K. pneumoniae. The findings broaden our scope of knowledge for polymyxin resistance and enriched our understanding of how bacteria can manage to survive in the presence of antibiotics.

Objective:To compare the clinicopathological differences between elderly and non-elderly patients with idiopathic membranous nephropathy(IMN).Methods:Patients diagnosed with IMN via renal biopsy at Beijing Huairou Hospital, Beijing Changping Hospital of Traditional Chinese Medicine, and Beijing Hospital of Traditional Chinese Medicine from January 2017 to August 2021 were retrospectively enrolled.They were classified into the elderly group(≥65 years)and the non-elderly group(<65 years), and the clinicopathological differences between the two groups were compared.Results:A total of 207 IMN patients were included in the study, with a male to female ratio of 1.7∶1.0.There were 56 patients in the elderly group, aged(68.2±3.1)years, and 151 patients in the non-elderly group, aged(48.2±6.2)years.Compared with the non-elderly group, the elderly group had a longer time from onset to renal biopsy and a higher proportion of patients with renal insufficiency and hypertension( P<0.05). The elderly group had a lower eGFR, lower serum albumin, higher serum cholesterol, and higher low-density lipoprotein than the non-elderly group( P<0.05). The proportions of patients with glomerulosclerosis, renal tubular atrophy, and interstitial fibrosis in the elderly group were higher than in the non-elderly group( P<0.05). The positive rates of glomerular PLA2R antigen staining in the two groups were 90.6%(29/32)and 91.0%(111/122), respectively, and there was no statistically significant difference between the two groups.IgG4 deposition represented the most common IgG subtype, with 93.8%(30/32)in the elderly group and 94.3%(115/122)in the non-elderly group.There was no statistical significance between the two groups( P>0.05). Conclusions:Compared with non-elderly IMN patients, a higher proportion of elderly IMN patients has renal insufficiency, hypertension and chronic renal pathology.The glomerular deposition of pathogenic antigens in elderly IMN patients was similar to that in non-elderly IMN patients, suggesting no difference in pathogenesis between the two groups.The clinicopathological differences between the two groups may be related to age and complications.

Objective:To analyze the skin microbiota diversity in patients with pemphigus vulgaris (PV) using 16S rDNA sequencing.Methods:Ten patients with PV and 10 healthy controls were collected from the Department of Dermatology, the Third People′s Hospital of Hangzhou. Skin swabs were collected from perilesional skin (PV group) and contralateral non-lesional skin (PVn group) of the patients with PV, as well as from the corresponding body sites of the healthy controls (normal control group) . The 16S rDNA amplicon sequencing technology was used for gene sequencing and classification in all microbiota samples, and Usearch software for data cluster analysis to obtain operational taxonomic units (OTUs) and assess species abundance at the phylum, class, order, family and genus levels. Observed species index, Shannon index and Simpson index were used to estimate α diversity, and principal coordinate analysis (PCoA) was performed to analyze β diversity. Linear discriminant analysis effect size (LEfSe) analysis was conducted to identify differentially abundant species in each group. PICRUSt software was used for gene function prediction. Wilcoxon rank sum test was used as nonparametric test for comparisons between 2 groups, and Kruskal Waills test as nonparametric test for comparisons among 3 groups.Results:There were 2 002, 1 869, 1 751, 1 611 and 1 120 OTUs at phylum, class, order, family and genus levels respectively. Cluster analysis showed that skin microbiome in the 3 groups mainly consisted of Firmicutes, Actinobacteria, Bacteroidetes and Proteobacteria at the phylum level. At the genus level, Staphylococcus was the most abundant in the PV group and PVn group, and Corynebacterium was the most abundant in the normal control group. The observed species index, Shannon index and Simpson index all significantly differed among the 3 groups (all P< 0.05) , and the Shannon index and Simpson index were significantly lower in the PV group (3.24±1.30, 0.70±0.19, respectively) than in the normal control group ( P< 0.05) . PCoA analysis showed no significant difference in β diversity among the 3 groups ( P=0.054) . Rank sum test showed that the abundance of 32 species significantly differed among the 3 groups ( P< 0.05) . Among them, high relative abundance was observed in the class Bacilli enriched in the PV group, as well as the genera Micrococcus and Brevundimonas enriched in the normal control group. According to the disease duration, the patients with PV were divided into long-course PV group with disease duration of ≥ 3 months, and short-course PV group with disease duration of < 3 months. Clostridiales, Oscillibacter, Sphingomonas were enriched in the long-course PV group, and Gammaproteobacteria was enriched in the short-course PV group. Gene function prediction analysis showed that the genes related to infectious diseases were enriched in the pemphigus group. Conclusion:The 16S rDNA-based microbiota profiling suggested differences in the diversity and composition of skin microbiota between patients with PV and healthy individuals.

Objective:To investigate the expressions and significances of autophagy-related genes Beclin-1, LC3 and p62 in esophageal squamous cell carcinoma (ESCC).Methods:The clinical data of 112 patients with primary ESCC who underwent surgery at the 81st Group Army Hospital of Chinese PLA from January 2015 to December 2016 were retrospectively analyzed. Immunohistochemistry was used to examine the expressions of Beclin-1, p62 and LC3 proteins in 112 ESCC tissues and 31 adjacent normal esophageal mucosa tissues. Furthermore, the expressions of the above three autophagy-related markers in ESCC and the relationship between their expressions and the clinicopathological characteristics of patients were analyzed.Results:The positive expression rates of Beclin-1, LC3 and p62 in ESCC tissues were 32.14% (36/112), 37.50% (42/112) and 63.39% (71/112), The positive expression rates of Beclin-1, LC3 and p62 in adjacent normal esophageal mucosa tissues were 61.29% (19/31), 64.52% (20/31) and 32.26% (10/31), and the differences were statistically significant ( χ2 values ??were 8.715, 7.216 and 9.584, all P < 0.01). The positive expression rates of Beclin-1 and LC3 in ESCC were lower than those in adjacent normal esophageal mucosa tissues, and the positive expression rate of p62 in ESCC was higher than that in adjacentnormal esophageal mucosa tissues. In ESCC patients, the expression of Beclin-1 was related to histological grade, infiltration depth, TNM staging and lymph node metastasis (all P < 0.05); the expression of LC3 was related to infiltration depth and TNM staging (both P < 0.01); the expression of p62 was related to lymph node metastasis ( P < 0.01). In ESCC, the expression of LC3 was positively correlated with the expression of Beclin-1 ( r = 0.731, P = 0.001), and negatively correlated with the expression of p62 ( r = -0.215, P = 0.023). Conclusions:Autophagy plays a certain role in the occurrence and development of ESCC. Combined detection of autophagy-related genes Beclin-1, p62 and LC3 can assist clinical diagnosis and guide follow-up comprehensive treatment.

Objective:To examine the expression of MHC class Ⅱ in medullary thyroid carcinoma(MTC) and analyze its clinical significance.Methods:98 MTC patients treated at Tumor Hospital of Tianjin Medical University from Jan 2010 to Dec 2018 were included for the study. Immunohistochemistry was used to detect the expression of MHC class Ⅱ molecule .Results:The high expression of MHC class Ⅱ was not correlated with age (χ 2=0.900, P=0.410), multifocal (χ 2=0.295, P=0.672), bilateral (χ 2=2.957, P=0.127), T stage (χ 2=0.554, P=0.457), but correlated with gender (χ 2=5.227, P=0.025), preoperative calcitonin level (χ 2=6.663, P=0.019), lymph node metastasis (χ 2=21.651, P<0.001) and AJCC stage (χ 2=19.522, P<0.001). Overall survival rate of patients with high expression of MHC class Ⅱ was 97.4%.It was significantly higher than that of patients with low expression 66.1% ( P=0.016 3). COX regression model showed that age >55 years old ( HR=4.129, P=0.009), T stage ( HR=3.265, P=0.024) were independent risk factors for the prognosis of MTC patients. High expression of MHC class Ⅱ molecules ( HR=0.103, P=0.030) was a protective factor for the prognosis of MTC patients. Conclusion:The MTC patients with high expression of MHC class Ⅱ have a better prognosis.

As d-amino acids play important roles in the physiological metabolism of bacteria, combination of d-amino acids with antibiotics may provide synergistic antibacterial activity. The aim of the study was to evaluate and activity of d-serine alone and in combination with -lactams against methicillin-resistant (MRSA) strains, and to explore the possible sensitization mechanisms. The activity of d-serine, -lactams alone and in combinations was evaluated both by standard MICs, time-kill curves and checkerboard assays, and by murine systemic infection model as well as neutropenic thigh infection model. An synergistic effect was demonstrated with the combination of d-serine and -lactams against MRSA standard and clinical strains. Importantly, the combinations enhanced the therapeutic efficacy in the animal models as compared to -lactam alone groups. Initial mechanism study suggested possible revision of d-alanine-d-alanine residue to d-alanine-d-serine in peptidoglycan by adding of d-alanine in the medium, which may cause decreased affinity to PBPs during transpeptidation. In conclusion, d-serine had synergistic activity in combination with -lactams against MRSA strains both and . Considering the relatively good safety of d-serine alone or in combination with -lactams, d-serine is worth following up as new anti-MRSA infection strategies.

Bacteremia is a life-threating syndrome often caused by methicillin-resistant (MRSA). Thus, there is an urgent need to develop novel approaches to successfully treat this infection. Staphylococcal accessory regulator A (SarA), a global virulence regulator, plays a critical role in pathogenesis and -lactam antibiotic resistance in . Hypericin is believed to act as an antibiotic, antidepressant, antiviral and non-specific kinase inhibitor. In the current study, we investigated the impact of hypericin on -lactam antibiotics susceptibility and mechanism(s) of its activity. We demonstrated that hypericin significantly decreased the minimum inhibitory concentrations of -lactam antibiotics (.., oxacillin, cefazolin and nafcillin), biofilm formation and fibronectin binding in MRSA strain JE2. In addition, hypericin significantly reduced expression, and subsequently decreased and virulence-related regulators (.., ) and genes (.., and ) expression in the studied MRSA strain. Importantly, the synergistic effect of hypericin with -lactam antibiotic (.., oxacillin) translated into therapeutic outcome in a murine MRSA bacteremia model. These findings suggest that hypericin plays an important role in abrogation of -lactam resistance against MRSA through inhibition, and may allow us to repurpose the use of -lactam antibiotics, which are normally ineffective in the treatment of MRSA infections (.., oxacillin).