Research Progress in Antibody Responses Against SARS-CoV-2 Variants of Concern / 中国医学科学院学报

So far,the coronavirus disease 2019(COVID-19)has been persisting for nearly three years,infecting about 700 million people and causing more than 6 million deaths,which has seriously affected the human society.According to Global Initiative on Sharing All Influenza Data,there are more than 12 million SARS-CoV-2 variants,of which the five major variants of concern are Alpha,Beta,Gamma,Delta and Omicron.Their infectivity,pathogencity,and neutralization resistance have changed greatly compared with the original strain,which has brought great pressure to the prevention and control of the pandemic.Antibody level testing is critical for confirming infection,epidemiological investigation,vaccine development,and neutralizing drug preparation.Focusing on the humoral immunity against SARS-CoV-2,this paper introduces the mutation sites,neutralization resistance,and vaccination efficacy of the five variants of concern,and briefly summarizes the evolutionary characteristics,future mutation directions,and host immunity.

Similarities and differences between D3 lymphadenectomy and complete mesocolic excision of right hemicolonectomy / 中华胃肠外科杂志

D3 lymphadenectomy and complete mesocolic excision (CME) for colon cancer, which have been introduced to China for more than 10 years, are two major surgical principles worldwide. However, there are still many different opinions and misunderstandings about the core principles of D3 and CME, especially the similarities and differences between them. However, few articles have been published to discuss these issues specifically. Domestic scholars' understandings about D3 lymphadenectomy and CME for right hemicolectomy are quite different. Two different concepts including "D3/CME" and "D3+CME" have become mainstream views. The former equate D3 with CME and the latter seems to regard them as totally different principles. There is no consensus on which one is more reasonable. Therefore, this article aims to discuss the similarities and differences between D3 and CME for right hemicolectomy in perspectives of the theoretical background, surgical principles, extent of surgery and oncological outcomes. We believed that D3 and CME do not belong to the same concept, and that the scope of CME surgery for right-sided colon cancer is greater than and includes the scope of D3 surgery, and that D3 and CME are not complementary.

Time of dissociation between microcirculation, macrocirculation, and lactate levels in a rabbit model of early endotoxemic shock / 中华医学杂志(英文版)

BACKGROUND@#The relationship between macrocirculation and microcirculation remains controversial. The loss of coherence between microcirculation and macrocirculation has already been found in late-stage sepsis shock. The objective of this study was to determine the earliest possible time of detecting the loss of coherence between microcirculation and macrocirculation in early-stage endotoxemic shock.@*METHODS@#We randomized 24 female New Zealand white rabbits into two groups: endotoxemic shock group (n = 14) and control group (n = 10). Rabbits in the endotoxemic shock group were equipped with arterial and venous catheters and received an intravenous infusion of Escherichia coli lipopolysaccharide (LPS, 2 mg/kg over 10 min). Rabbits in the control group received the same dose of saline infusion. Microcirculatory perfusion parameters were assessed in the sublingual mucosa using sidestream dark-field video microscopy. Systemic hemodynamics and blood lactate levels were measured at baseline and over a 120-min period.@*RESULTS@#Ninety minutes after completing LPS infusion, all animals in the endotoxemic shock group developed a hypodynamic septic condition, characterized by low cardiac output and increased systemic vascular resistance; 120 min after completing LPS infusion, the mean arterial pressure decreased by 25% (P = 0.01), confirming ongoing endotoxemic shock. However, significant decreases in sublingual microcirculatory parameters of small vessels (microvascular flow index, perfused vessel density, and proportion of small perfused vessels) were observed 30 min after completing LPS infusion (P = 0.01, for all), and threshold decreases of 30% were found 60 min after completing LPS infusion (P = 0.001, for all) in the endotoxemic shock group. Lactate levels significantly increased to more than 2 mm/L at 90 min and more than 4 mm/L at 120 min in the endotoxemic shock group (P = 0.02 and P = 0.01, respectively).@*CONCLUSIONS@#Changes in microcirculatory perfusion precede changes in macrocirculation and lactate levels in a rabbit model of endotoxemia shock. Microcirculation, macrocirculation, and oxygen metabolism are distinct in early-stage endotoxic shock.

Effects of rhubarb on the expression of glucocorticoids receptor and regulation of cellular immunity in burn-induced septic rats / 中华医学杂志(英文版)

Background:@#It is important to modulate the expression of glucocorticoids receptor (GR) in tress and maintain the immunity homeostasis in sepsis process. Rhubarb have been shown to have potential effects on anti-inflammatory and immune modulation. The present study was designed to investigate the effects of rhubarb on the expression of GR and cellular immunity in burn-induced septic rats.@*Methods:@#Sixty-six healthy male Sprague Dawley (SD) rats were randomized into sepsis group (n = 24), rhubarb group (n = 24), and control group (n = 18); each group were further randomized into 12, 24, and 72 h subgroups according to different time points. During onset of the sepsis model, the rats in the rhubarb group were infused with 50 mg/kg rhubarb powder dissolved into 1 mL saline through gastric tube, while sepsis and control groups were treated with saline. The binding activity of GR in liver cytosol and binding capacity of GR in peripheral blood leucocyte were analyzed by radiation ligands binding assay. The percentages of CD4+, CD8+,CD4+CD25+T cells, CD19+B cells as well as natural killer (NK) cells in the lymphocytes in peripheral blood were detected by flow cytometer. For assessing the differences among groups, one-way analysis of variance (ANOVA) with Scheffe multi-comparison techniques were employed. Comparisons between time-based measurements within each group were performed with ANOVA repeated measurement.@*Results:@#The binding activity of GR in liver cytosol and binding capacity of GR in peripheral blood leucocyte were significantly decreased in a time-dependent manner in sepsis group (t = 23.045, P < 0.01; t = 24.395, P < 0.05, respectively), which were increased in a time-dependent manner after rhubarb administration (t = 19.965, P < 0.05; t = 17.140, P < 0.05, respectively). Twelve hours after sepsis, the percentages of CD4+ T cells, CD4+/CD25+ T cell ratio, and CD19+ B cells in the peripheral blood were significantly increased in the sepsis group (t = -3.395, P < 0.01; t = 2.568, P < 0.05; t = 2.993, P < 0.05, vs. control mice, respectively). However, the percentage of NK cells in the peripheral blood were significantly decreased in the sepsis group (t = -2.022, P < 0.05, vs. control mice). Twelve hours after sepsis, the percentage of CD8+ T cells were significantly decreased in the peripheral blood in the sepsis group (t = -2.191, P < 0.05, vs. control mice) and were significantly increased in the rhubarb group (t = 2.953, P < 0.05, vs. sepsis mice). Seventy-two hours after sepsis, the ratio of CD4+/CD25+ T cell in peripheral blood were significantly increased in the sepsis group (t = 2.508, P < 0.05, vs. control mice) while were significantly decreased in the rhubarb group (t = 3.378, P < 0.05, vs. control mice). Furthermore, the percentages of CD19+ B cell in peripheral blood were significantly decreased at 72 h in the rhubarb group (t = 2.041, P < 0.05 vs. sepsis group).@*Conclusions:@#Rhubarb might play potential anti-inflammatory and immunomodulatory roles in the sepsis processes.

Effect of broad-spectrum antibiotics on bacterial translocation in burned or septic rats / 中华医学杂志(英文版)

Background:@#Antibiotics are frequently used to treat critically ill patients, and its use is often accompanied by intestinal dysbiosis that might further lead to bacterial translocation (BT). Nevertheless, studies on the relationship between antibiotic therapy and BT are rare. In the present study, we investigated the effect of broad-spectrum antibiotics on BT in an experimental rat model of burn or sepsis injury.@*Methods:@#The septic rat model was simulated by a second insult with lipopolysaccharides after burn injury. Ninety-two male Sprague-Dawley rats were randomly divided into control, burn, and sepsis groups (n = 8 or 9, each group), and the latter two groups were then treated with imipenem or ceftriaxone for 3 or 9 days. The mesenteric lymph nodes, liver, lungs, and blood were collected at each time point under sterile conditions for quantitative bacterial culture and strain identification. The differences between the groups were compared by Fisher exact test or Mann-Whitney U test.@*Results:@#Only minimal Escherichia coli translocation to the mesenteric lymph nodes was observed in the normal control group, in which the BT rate was 12.5%. Burn injury did not affect the BT rate (Burn group vs. Control group, 12.5% vs. 12.5%, P = 1.000), whereas the BT rate showed an increased trend after the second insult with lipopolysaccharide (Sepsis group vs. Control group, 44.4% vs. 12.5%, P = 0.294), and many strains of Enterobacteria spp. were detected in distant organs (liver, lung, and blood) [Sepsis group vs. Control group, 0 (0,3) vs. 0 (0,0), U = 20, P = 0.045]. After the antibiotic treatment, BT to the distant organs was increased in burned rats [Burn IT3 group vs. Burn group, 0 (0,2) vs. 0 (0,0); Burn IT9 group vs. Burn group, 0 (0,1) vs. 0 (0,0); Burn CT9 group vs. Burn group, 0 (0,2) vs. 0 (0,0); all U = 20 and P = 0.076] but decreased in septic rats [Sepsis CT3 group vs. Sepsis group, 0 (0,0) vs. 0 (0,3), U = 20, P = 0.045]. The total amount of translocated bacteria, regardless of which antibiotic was used, was increased in burned rats [Burn IT9 group vs. Burn group, 2.389 (0,2.845) vs. 0 (0,2.301) Log10 colony-forming units (CFU)/g, U = 14, P = 0.034; Burn CT3 group vs. Burn group, 2.602 (0,3.633) vs. 0 (0,2.301) Log10 CFU/g, U = 10.5, P = 0.009], but there was a slightly decreased trend in septic rats [Sepsis IT9 group vs. Sepsis group, 2.301 (2,3.146) vs. 0 (0,4.185) Log10 CFU/g, U = 36, P = 0.721; Sepsis CT9 group vs. Sepsis group, 2 (0,3.279) vs. 0 (0,4.185) Log10 CFU/g, U = 32.5, P = 0.760]. Remarkably, the quantity of Enterococci spp. dramatically increased after broad-spectrum antibiotic treatment in both the burned and septic groups [Burn IT3 group vs. Burn group, 1 (0,5.164) vs. 0 (0,0) Log10 CFU/g, U = 16; Burn IT9 group vs. Burn group, 1 (0,2.845) vs. 0 (0,0) Log10 CFU/g, U = 16; Burn CT3 group vs. Burn group, 2.602 (0,3.633) vs. 0 (0,0) Log10 CFU/g, U = 8; Burn CT9 group vs. Burn group, 1 (0,4.326) vs. 0 (0,0) Log10 CFU/g, U = 16; Sepsis IT3 group vs. Sepsis group, 2.477 (0,2.903) vs. 0 (0,0) Log10 CFU/g, U = 4.5; Sepsis IT9 group vs. Sepsis group, 2 (0,3.146) vs. 0 (0,0) Log10 CFU/g, U = 9; Sepsis CT3 group vs. Sepsis group, 1.151 (0,2.477) vs. 0 (0,0) Log10 CFU/g, U = 18; Sepsis CT9 group vs. Sepsis group, 2 (0,3) vs. 0 (0,0) Log10 CFU/g, U = 13.5; all P < 0.05].@*Conclusions:@#Broad-spectrum antibiotics promote BT in burned rats but prevent BT in septic rats, especially preventing BT to distant organs, such as the liver and lung. Moreover, Enterococci spp. with high drug resistance and high pathogenicity translocated most after antibiotic treatment.

Effect of broad-spectrum antibiotics on bacterial translocation in burned or septic rats / 中华医学杂志(英文版)

BACKGROUND@#Antibiotics are frequently used to treat critically ill patients, and its use is often accompanied by intestinal dysbiosis that might further lead to bacterial translocation (BT). Nevertheless, studies on the relationship between antibiotic therapy and BT are rare. In the present study, we investigated the effect of broad-spectrum antibiotics on BT in an experimental rat model of burn or sepsis injury.@*METHODS@#The septic rat model was simulated by a second insult with lipopolysaccharides after burn injury. Ninety-two male Sprague-Dawley rats were randomly divided into control, burn, and sepsis groups (n = 8 or 9, each group), and the latter two groups were then treated with imipenem or ceftriaxone for 3 or 9 days. The mesenteric lymph nodes, liver, lungs, and blood were collected at each time point under sterile conditions for quantitative bacterial culture and strain identification. The differences between the groups were compared by Fisher exact test or Mann-Whitney U test.@*RESULTS@#Only minimal Escherichia coli translocation to the mesenteric lymph nodes was observed in the normal control group, in which the BT rate was 12.5%. Burn injury did not affect the BT rate (Burn group vs. Control group, 12.5% vs. 12.5%, P = 1.000), whereas the BT rate showed an increased trend after the second insult with lipopolysaccharide (Sepsis group vs. Control group, 44.4% vs. 12.5%, P = 0.294), and many strains of Enterobacteria spp. were detected in distant organs (liver, lung, and blood) [Sepsis group vs. Control group, 0 (0,3) vs. 0 (0,0), U = 20, P = 0.045]. After the antibiotic treatment, BT to the distant organs was increased in burned rats [Burn IT3 group vs. Burn group, 0 (0,2) vs. 0 (0,0); Burn IT9 group vs. Burn group, 0 (0,1) vs. 0 (0,0); Burn CT9 group vs. Burn group, 0 (0,2) vs. 0 (0,0); all U = 20 and P = 0.076] but decreased in septic rats [Sepsis CT3 group vs. Sepsis group, 0 (0,0) vs. 0 (0,3), U = 20, P = 0.045]. The total amount of translocated bacteria, regardless of which antibiotic was used, was increased in burned rats [Burn IT9 group vs. Burn group, 2.389 (0,2.845) vs. 0 (0,2.301) Log10 colony-forming units (CFU)/g, U = 14, P = 0.034; Burn CT3 group vs. Burn group, 2.602 (0,3.633) vs. 0 (0,2.301) Log10 CFU/g, U = 10.5, P = 0.009], but there was a slightly decreased trend in septic rats [Sepsis IT9 group vs. Sepsis group, 2.301 (2,3.146) vs. 0 (0,4.185) Log10 CFU/g, U = 36, P = 0.721; Sepsis CT9 group vs. Sepsis group, 2 (0,3.279) vs. 0 (0,4.185) Log10 CFU/g, U = 32.5, P = 0.760]. Remarkably, the quantity of Enterococci spp. dramatically increased after broad-spectrum antibiotic treatment in both the burned and septic groups [Burn IT3 group vs. Burn group, 1 (0,5.164) vs. 0 (0,0) Log10 CFU/g, U = 16; Burn IT9 group vs. Burn group, 1 (0,2.845) vs. 0 (0,0) Log10 CFU/g, U = 16; Burn CT3 group vs. Burn group, 2.602 (0,3.633) vs. 0 (0,0) Log10 CFU/g, U = 8; Burn CT9 group vs. Burn group, 1 (0,4.326) vs. 0 (0,0) Log10 CFU/g, U = 16; Sepsis IT3 group vs. Sepsis group, 2.477 (0,2.903) vs. 0 (0,0) Log10 CFU/g, U = 4.5; Sepsis IT9 group vs. Sepsis group, 2 (0,3.146) vs. 0 (0,0) Log10 CFU/g, U = 9; Sepsis CT3 group vs. Sepsis group, 1.151 (0,2.477) vs. 0 (0,0) Log10 CFU/g, U = 18; Sepsis CT9 group vs. Sepsis group, 2 (0,3) vs. 0 (0,0) Log10 CFU/g, U = 13.5; all P < 0.05].@*CONCLUSIONS@#Broad-spectrum antibiotics promote BT in burned rats but prevent BT in septic rats, especially preventing BT to distant organs, such as the liver and lung. Moreover, Enterococci spp. with high drug resistance and high pathogenicity translocated most after antibiotic treatment.

Effects of rhubarb on the expression of glucocorticoids receptor and regulation of cellular immunity in burn-induced septic rats / 中华医学杂志(英文版)

BACKGROUND@#It is important to modulate the expression of glucocorticoids receptor (GR) in tress and maintain the immunity homeostasis in sepsis process. Rhubarb have been shown to have potential effects on anti-inflammatory and immune modulation. The present study was designed to investigate the effects of rhubarb on the expression of GR and cellular immunity in burn-induced septic rats.@*METHODS@#Sixty-six healthy male Sprague Dawley (SD) rats were randomized into sepsis group (n = 24), rhubarb group (n = 24), and control group (n = 18); each group were further randomized into 12, 24, and 72 h subgroups according to different time points. During onset of the sepsis model, the rats in the rhubarb group were infused with 50 mg/kg rhubarb powder dissolved into 1 mL saline through gastric tube, while sepsis and control groups were treated with saline. The binding activity of GR in liver cytosol and binding capacity of GR in peripheral blood leucocyte were analyzed by radiation ligands binding assay. The percentages of CD4,CD8,CD4CD25T cells, CD19B cells as well as natural killer (NK) cells in the lymphocytes in peripheral blood were detected by flow cytometer. For assessing the differences among groups, one-way analysis of variance (ANOVA) with Scheffe multi-comparison techniques were employed. Comparisons between time-based measurements within each group were performed with ANOVA repeated measurement.@*RESULTS@#The binding activity of GR in liver cytosol and binding capacity of GR in peripheral blood leucocyte were significantly decreased in a time-dependent manner in sepsis group (t = 23.045, P < 0.01; t = 24.395, P < 0.05, respectively), which were increased in a time-dependent manner after rhubarb administration (t = 19.965, P < 0.05; t = 17.140, P < 0.05, respectively). Twelve hours after sepsis, the percentages of CD4 T cells, CD4/CD25 T cell ratio, and CD19 B cells in the peripheral blood were significantly increased in the sepsis group (t = -3.395, P < 0.01; t = 2.568, P < 0.05; t = 2.993, P < 0.05, vs. control mice, respectively). However, the percentage of NK cells in the peripheral blood were significantly decreased in the sepsis group (t = -2.022, P < 0.05, vs. control mice). Twelve hours after sepsis, the percentage of CD8 T cells were significantly decreased in the peripheral blood in the sepsis group (t = -2.191, P < 0.05, vs. control mice) and were significantly increased in the rhubarb group (t = 2.953, P < 0.05, vs. sepsis mice). Seventy-two hours after sepsis, the ratio of CD4/CD25 T cell in peripheral blood were significantly increased in the sepsis group (t = 2.508, P < 0.05, vs. control mice) while were significantly decreased in the rhubarb group (t = 3.378, P < 0.05, vs. control mice). Furthermore, the percentages of CD19 B cell in peripheral blood were significantly decreased at 72 h in the rhubarb group (t = 2.041, P < 0.05 vs. sepsis group).@*CONCLUSIONS@#Rhubarb might play potential anti-inflammatory and immunomodulatory roles in the sepsis processes.

Attitudes of 8-year program medical students to concept mapping after the pharmacology teaching/learning practice and analysis of the learning readiness for students / 基础医学与临床

Concept mapping is a new method to help learners organizing their knowledge with a visual semantic net-work. In the process of pharmacology teaching concept mapping are used as a teaching tool and a learning tool, respectively. Then a survey was conducted on 8-year program medical students to obtain information regarding students attitude towards concept mapping in pharmacology teaching and learning as well as their learning readiness. The authors hope the information may play a direction role for the teaching activity in the future and make Pharmacology teaching contents and methods meet the knowledge requirement and learning readiness of medical students.

Effect of Rhubarb on Gastrointestinal Dysfunction in Critically Ill Patients: A Retrospective Study Based on Propensity Score Matching / 中华医学杂志(英文版)

<p><b>Background</b>Gastrointestinal dysfunction plays a critical role in the prognosis of critically ill patients. Previous studies showed rhubarb, a traditional Chinese herb, can protect the intestinal barrier function, prevent intestinal bacterial translocation, and promote gastrointestinal peristalsis, but the clinical studies are less. The aim of this study was to evaluate the effects of rhubarb on gastrointestinal dysfunction in critically ill patients.</p><p><b>Methods</b>From June 2015 to May 2017, a total of 368 critically ill patients with Grade I-III acute gastrointestinal injury (AGI) were enrolled in this study. Patients were divided into two groups according to the exposure factors (whether the patients received rhubarb treatment): the rhubarb group and the usual treatment group. Clinical data were collected within the first 24 h of the Intensive Care Unit (ICU) admission and 7 days after treatment. Survival data on day 28 after ICU admission and the durations of ICU and total hospitalization were also collected. Propensity score matching (PSM) was conducted to reduce confounding bias between the groups. The logistic regression was conducted to screen the influence factors.</p><p><b>Results</b>The eligible patients were divided into rhubarb group (n = 219, 59.5%) and usual treatment group (n = 149, 40.5%). Before PSM, the remission rate of feeding intolerance in rhubarb group and usual treatment group were 59.8% and 39.6%, respectively. After PSM, the remission rate of feeding intolerance in rhubarb group and usual treatment group was 77.9% and 30.9%, respectively. The remission rates of feeding intolerance in rhubarb group were significantly higher than those in the usual treatment group (all P < 0.05). Compared with the usual treatment group, the rhubarb group had a higher rate of AGI improvement, lower level of C-reactive protein, shorter stay in ICU before and after PSM (P < 0.05). There was no significant difference in 28-day mortality between rhubarb and usual treatment groups before and after PSM (48 vs. 33, P = 0.959; and 16 vs. 21, P = 0.335). The logistic regression analysis showed that the single factor, whether receiving rhubarb therapy, affected the proportion of patients whose enteral nutrition needs ≥83.7 kJ·kg·d after 7 days of treatment (odds ratio: 7.908, 95% confidence interval: 3.661-17.083, P < 0.001). No serious adverse effects were found in two groups.</p><p><b>Conclusions</b>The rhubarb might significantly improve feeding tolerance and relieve gastrointestinal dysfunction in critically ill patients, without serious adverse reactions. It provided proof for the treatment of gastrointestinal dysfunction with rhubarb during clinical practice.</p>

Influence of perivascular space enlargement on the prognosis of acute anterior circulation mild stroke / 医学研究生学报

Objective Few studies are reported on the influence of perivascular space enlargement (PVSE) on the prognosis of cerebral infarction. This study was to investigate the clinical correlation of EPVS in the basal ganglia and central semiovale with the prognosis of the first acute cerebral infarction (ACI) with anterior circulation mild small-artery occlusion (SAO).Methods We treated 137 cases of the first ACI with anterior circulation mild SAO in Tangshan Gongren Hospital from August 2015 to October 2016. According to the scores on PVSE in the basal ganglia and central semiovale, we divided the patients into a mild PVSE (score: 0-1) and a severe PVSE group (score: 2-4). Based on the National Institutes of Health Stroke Scale (NHISS) and the modified Rankin Scale (MRS) scores, we classified the outcome of neurological function recovery as good (MRS≥2) and poor (MRS<2) and analyzed the risk factors for the poor prognosis of ACI by logistic regression analysis.Results There were 60 cases of severe and 77 cases of mild PVSE in the in the basal ganglia as compared with 57 cases of severe and 80 cases of mild PVSE in the in the central semiovale. Good prognosis was achieved in 97 cases while poor prognosis observed in 40. Multivariate logistic regression analysis showed that the risk factors for the poor prognosis of ACI included NHISS at the onset (OR=5.393, 95% CI: 1.858-15.654), hypertension (OR=3.729, 95% CI: 1.310-10.610), and the severity of PVSE in the basal ganglia (OR=3.137, 95% CI: 1.343-7.325).Conclusion For the first acute cerebral infarction with anterior circulation mild small-artery occlusion, the severity of PVSE in the basal ganglia is an important factor affecting the recovery of neurological function.

Rhubarb Monomers Protect Intestinal Mucosal Barrier in Sepsis via Junction Proteins / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Leakage of the intestinal mucosal barrier may cause translocation of bacteria, then leading to multiorgan failure. This study hypothesized that rhubarb monomers might protect the gut mucosal barrier in sepsis through junction proteins.</p><p><b>METHODS</b>Healthy male Sprague-Dawley rats (weighing 230-250 g) under anesthesia and sedation were subjected to cecal ligation and perforation (CLP). After surgical preparation, rats were randomly assigned to eight groups (n = 6 or 8 each group): sham group (Group A: normal saline gavage); sepsis group (Group B: normal saline gavage); Group C (intraperitoneally, dexamethasone 0.5 mg/kg) immediately after CLP surgery; and rhubarb monomer (100 mg/kg in normal saline)-treated groups (Group D: rhein; Group E: emodin; Group F: 3,8-dihydroxy-1-methyl-anthraquinone-2-carboxylic acid; Group G: 1-O-caffeoyl-2-(4-hydroxy-O-cinnamoyl)-D-glucose; and Group H: daucosterol linoleate). Animals were sacrificed after 24 h. Intestinal histology, lactulose, mannitol concentrations were measured, and zonula occludens (ZO)-1, occludin and claudin-5 transcription (polymerase chain reaction), translation (by Western blot analysis), and expression (by immunohistochemistry) were also measured.</p><p><b>RESULTS</b>Intestinal histology revealed injury to intestinal mucosal villi induced by sepsis in Group B, compared with Group A. Compared with Group A (0.17 ± 0.41), the pathological scores in Groups B (2.83 ± 0.41, P < 0.001), C (1.83 ± 0.41, P < 0.001), D (2.00 ± 0.63, P < 0.001), E (1.83 ± 0.41, P < 0.001), F (1.83 ± 0.75, P < 0.001), G (2.17 ± 0.41, P < 0.001),and H (1.83 ± 0.41, P < 0.001) were significantly increased. Lactulose/mannitol (L/M) ratio in Group B (0.046 ± 0.003) was significantly higher than in Group A (0.013 ± 0.001, P< 0.001) while L/M ratios in Groups C (0.028 ± 0.002, P< 0.001), D (0.029 ± 0.003, P< 0.001), E (0.026 ± 0.003, P< 0.001), F (0.027 ± 0.003, P< 0.001), G (0.030 ± 0.005, P< 0.001), and H (0.026 ± 0.002, P< 0.001) were significantly lower than that in Group B. ZO-1, occludin and claudin-5 transcription, translation, and expression in Group B were significantly lower than that in Group A (P < 0.001), but they were significantly higher in Groups C, D, E, F, G, and H than those in Group B (P < 0.05).</p><p><b>CONCLUSION</b>Rhubarb monomer treatment ameliorated mucosal damage in sepsis via enhanced transcription, translation, and expression of junction proteins.</p>

Lipopolysaccharide Stimulates Surfactant Protein-A in Human Renal Epithelial HK-2 Cells through Upregulating Toll-like Receptor 4 Dependent MEK1/2-ERK1/2-NF-κB Pathway / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Surfactant protein-A (SP-A) contributes to the regulation of sepsis-induced acute kidney injury. In a previous study, we demonstrated that the expression of SP-A in the human renal tubular epithelial (HK-2) cells can be stimulated by lipopolysaccharide (LPS). The present study evaluated the possible signal-transducing mechanisms of LPS-induced SP-A biosynthesis in the HK-2 cells.</p><p><b>METHODS</b>Tetrazolium salt colorimetry (MTT) assay was used to detect cell viability of HK-2 cells after LPS stimulation on different time points. HK-2 cells were stimulated with 100 ng/ml of LPS for different durations to determine the effects of LPS on SP-A and toll-like receptor 4 (TLR4) messenger RNA (mRNA) expression, as well as phosphorylation of mitogen-activated/extracellular signal-regulated kinase (MEK) 1, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 mitogen-activated protein kinase (p38MAPK), and nuclear factor-kappa B (NF-κB) inhibitor-alpha (IkB-α). Then, HK-2 cells were pretreated with CLI-095, a TLR4 inhibitor, to analyze mRNA and protein levels of SP-A and TLR4 and expression of NF-κB in the cytoplasm and nucleus of HK-2 before LPS exposure.</p><p><b>RESULTS</b>HK-2 cells exposed to 100 ng/ml of LPS for 1, 6, and 24 h did not affect cell viability which showed no toxic effect of 100 ng/ml LPS on cells (P = 0.16); however, the biosynthesis of SP-A mRNA and protein in HK-2 cells was significantly increased (P = 0.02). As to the mechanism, LPS enhanced transmembrane receptor TLR4 protein expression. Sequentially, LPS time dependently augmented phosphorylation of MEK1, ERK1/2, and p38MAPK. In addition, levels of phosphorylated IκB-α and nuclear NF-κB were augmented with LPS exposure for 2 h. LPS-induced SP-A and TLR4 mRNA as well as NF-κB expression were significantly inhibited by pretreatment with CLI-095.</p><p><b>CONCLUSIONS</b>The present study exhibited that LPS can increase SP-A synthesis in human renal epithelial cells through sequentially activating the TLR4-related MEK1-ERK1/2-NF-κB-dependent pathway.</p>

Research Advances in Resistance to Platinum-based Chemotherapy in Lung Cancer / 中国医学科学院学报

Platinum-based chemotherapy is the the cornerstone of treatment of many cancers. Combinations of platinum drugs with other agents are still the mainstream therapies for non-small cell lung cancer,showing significant effectiveness in an early phase. Along with the treatment,the tumor cells can become resistant to chemotherapy drugs,which affect the efficacy and prognosis. The mechanisms of drug resistance are complicated,including abnormal expressions of membrane proteins,enhanced DNA repair functions,abnormal regulation mechanisms of apoptosis,and enhanced cellular detoxification function. In this article we summarize some of the main mechanisms of platinum resistance in lung cancer cells,with an attempt to identify new potential target analogues or inhibitors and improve the efficacies of the combined use of platinum-based drugs.

Combination of carboxyamidotriazole and 1-Methyl-L-tryptophan has synergistic inhibtory effects on programmed death 1 expression / 中国药理学与毒理学杂志

OBJECTIVE To evaluate whether the IDO1 inhibitor 1- methyl- L- tryptophan (1- MT) combine calcium influx inhibitor carboxyamidotriazole (CAI) could further enhance the suppression of programmed death 1 (PD-1) in CD8 + T cells and investigate the curative effect of the combined use. METHODS CD8 +T cells were isolated from normal mice spleen by negative selection using magnetic cell separation. The isolated CD8 +T cells were cultured in RPMI 1640 medium containing 10% FBS and 100 U·mL- 1 IL-2 and activated by the addition of anti-CD3 and anti-CD28 (1 g·L- 1 each mabs). CD8 + T cells were pretreated for 48 h with drug and the fluo- 3 as a marker of intracellular calcium concentration was detected by flow cytometry. The calcineurin (CaN) levels were assayed with ELISA in CD8+T cells after 48 h incubation with 10 μm CAI. The nuclear translocations of NFAT and AHR were detected by immunofluorescent staining after 48 h of drug treatment. The expression of PD-1 in CD8+T cells was analyzed by flow cytometry. RESULTS Intracellular fluorescent intensity was markedly debase due to CAI treatment(P<0.01). Meanwhile, the changes of CaN content had a resembled correlation (P<0.01). Immunofluorescence experiment showed that after combination therapy the transfer of NFAT and AHR in nuclear substantially reduced. Flow cytometry revealed that after the combination caused a significant decrease in PD-1 expression in CD8+T cells. CONCLUSION CAI and 1-MT could inhibit markedly the expression of PD-1 in CD8 +T cells by inhibiting the nuclear translocation of NFAT and AHR, respectively and the combination of them has synergetic effect.

Rhubarb Antagonizes Matrix Metalloproteinase-9-induced Vascular Endothelial Permeability / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Intact endothelial structure and function are critical for maintaining microcirculatory homeostasis. Dysfunction of the latter is an underlying cause of various organ pathologies. In a previous study, we showed that rhubarb, a traditional Chinese medicine, protected intestinal mucosal microvascular endothelial cells in rats with metastasizing septicemia. In this study, we investigated the effects and mechanisms of rhubarb on matrix metalloproteinase-9 (MMP9)-induced vascular endothelial (VE) permeability.</p><p><b>METHODS</b>Rhubarb monomers were extracted and purified by a series of chromatography approaches. The identity of these monomers was analyzed by hydrogen-1 nuclear magnetic resonance (NMR), carbon-13 NMR, and distortionless enhancement by polarization transfer magnetic resonance spectroscopy. We established a human umbilical vein endothelial cell (HUVEC) monolayer on a Transwell insert. We measured the HUVEC permeability, proliferation, and the secretion of VE-cadherin into culture medium using fluorescein isothiocyanate-dextran assay, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, and enzyme-linked immunosorbent assay, respectively, in response to treatment with MMP9 and/or rhubarb monomers.</p><p><b>RESULTS</b>A total of 21 rhubarb monomers were extracted and identified. MMP9 significantly increased the permeability of the HUVEC monolayer, which was significantly reduced by five individual rhubarb monomer (emodin, 3,8-dihydroxy-1-methyl-anthraquinone-2-carboxylic acid, 1-O-caffeoyl-2-(4-hydroxyl-O-cinnamoyl)-β-D-glucose, daucosterol linoleate, and rhein) or a combination of all five monomers (1 μmol/L for each monomer). Mechanistically, the five-monomer mixture at 1 μmol/L promoted HUVEC proliferation. In addition, MMP9 stimulated the secretion of VE-cadherin into the culture medium, which was significantly inhibited by the five-monomer mixture.</p><p><b>CONCLUSIONS</b>The rhubarb mixture of emodin, 3,8-dihydroxy-1-methyl-anthraquinone-2-carboxylic acid, 1-O-caffeoyl-2-(4-hydroxyl-O-cinnamoyl)-β-D-glucose, daucosterol linoleate, and rhein, at a low concentration, antagonized the MMP9-induced HUVEC monolayer permeability by promoting HUVEC proliferation and reducing extracellular VE-cadherin concentrations.</p>

Comparative Study of Plasma Endotoxin with Procalcitonin Levels in Diagnosis of Bacteremia in Intensive Care Unit Patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Both procalcitonin (PCT) and plasma endotoxin levels cannot be solely used for a definite diagnosis of bacteremia or sepsis, and there has been few study comparing the values of the two biomarkers for the diagnosis of bacteremia. The aim of this study was to identify bacteria causing bacteremia and evaluate the role of the two biomarkers in the diagnosis of bacteremia in Intensive Care Unit (ICU).</p><p><b>METHODS</b>The medical records of 420 patients in ICU were retrospectively reviewed. Patients (n = 241) who met the inclusion criteria were subjected to blood culture (BC) for the analysis of the endotoxin or PCT levels. The exclusion criteria included the presence of infection with human immunodeficiency virus and/or AIDS, neutropenia without sepsis, pregnancy, treatment with immunosuppressive therapies, or blood diseases such as hematological tumors. Patients' BC episodes were divided into BC negative, Gram-negative (GN) bacteria, Gram-positive bacteria, and fungi groups. The PCT and plasma endotoxin levels were compared in the different groups.</p><p><b>RESULTS</b>A total of 241 patients with 505 episodes of BC were analyzed. The GN bacteria group showed higher levels of PCT and endotoxin than the BC negative, Gram-positive bacteria, and fungi groups. GN bacteremia was more prevalent than Gram-positive bacteremia. The GN bacteremia caused by non-Enterobacteriaceae infection presented higher endotoxin level than that by Enterobacteriaceae, but no significant difference in PCT levels was observed between the two groups. The plasma endotoxin significantly differed among different groups and was bacterial species dependent.</p><p><b>CONCLUSIONS</b>Plasma endotoxin was more related to GN than to Gram-positive bacteremia, and that endotoxin level was species dependent, but PCT level remained relatively more stable within the GN bacteria caused bacteremia. Both GN and positive bacteria caused bacteremia in the ICU patients in different regions of China. And PCT is a more valuable biomarker than endotoxin in the diagnosis of bacteremia.</p>

Therapeutic Effect of Carboxyamidotriazole on Adjuvant Arthritis in Rats / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the effect of carboxyamidotriazole (CAI) on adjuvant arthritis (AA) in rats.</p><p><b>METHODS</b>The rats were randomly divided into normal group,two vehicle groups (polyethylene glycol 400 control and normal sodium control group), CAI-treated groups (10, 20, and 40 mg/kg) and positive control dexamethasone group. Freund's completed adjuvant was used to induce AA in rats. The arthritis index (AI) was scored, and X-ray check of the hind limbs and histopathological examination were performed. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the inflamed paw tissues were measured.</p><p><b>RESULTS</b>The administration of CAI significantly decreased the AI, restored the body weights, and ameliorated the radiological and histopathological features of joint destruction in AA rats (P<0.05, P<0.01). In addition, CAI reduced the TNF-α, IL-1β, and IL-6 levels in the inflamed paw tissues (P<0.05, P<0.01).</p><p><b>CONCLUSION</b>CAI has therapeutic effect on AA rats, which may be achieved by decreasing the pro-inflammatory cytokines at the site of inflammation.</p>

Establishment of a method for gene complementation in Vibrio parahaemolyticus / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method for gene complementation in Vibrio parahaemolyticus using the plasmid pBAD33.</p><p><b>METHODS</b>The entire coding region of opaR or aphA was amplified by PCR and cloned into pBAD33. The recombinant plasmid was transformed into δopaR and δaphA (the opaR or aphA null mutant strain, respectively) separately to construct the complemented mutant strain C-δaphA and C-δopaR, respectively. RT-PCR was used to verify the transcription of opaR and aphA in the corresponding complemented mutant strains. Primer extension experiments were performed to determine the relative mRNA levels of mfpA (a gene previously characterized to be negatively regulated by AphA and positively by OpaR) in the wild-type strain, δopaR, δaphA, C-δaphA, and C-δopaR.</p><p><b>RESULTS</b>opaR and aphA were transcribed in the corresponding complemented mutant strains, and their mRNA levels were comparable to those detected in the wild-type strains.</p><p><b>CONCLUSION</b>A method has been established for gene complementation in Vibrio parahaemolyticus using the plasmid pBAD33.</p>

Epidemiology of methicillin-resistant Staphylococcus aureus infection and empirical antibiotic therapy for MRSA infection: multicenter investigation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) maybe changed by strict infection control measures, and the impact of empirical antibiotic therapy on the outcomes of MRSA infection was not clear. We aimed to investigate the present epidemiological status of MRSA infection and empirical antibiotic therapy for MRSA infection in university teaching hospitals in mainland China.</p><p><b>METHODS</b>The present study was a multicenter prospective observational study conducted in five university teaching hospitals. Patients who were consecutively admitted to the intensive care unit and signed a consent form from March 3, 2011 to May 31, 2011 were included. Patients with age <18 years or with a length of hospital stay <48 hours were excluded from this study. The following variables were collected or recorded: demographic data, general status, APACHE II score of the patient at the time of admission, infections, and the use of antibiotics during a stay. Primary outcomes and prognostic indicators included length of hospital stay and 28-day and 90-day mortality. The differences between the patients with appropriate empirical therapy and patients with inappropriate therapy were analyzed to detect the influences of antibiotic therapy on the prognosis of MRSA infection.</p><p><b>RESULTS</b>A total of 682 cases were enrolled. Thirty (66.2%) of 88 MRSA cases were treated with effective antibiotics for MRSA infection; only 20% received appropriate empirical antibiotic treatment. The empirical therapy group compared with the target therapy group had a shorter length of stay, but there were no significant differences in mortality rates. There were no significant differences in the length of hospital stay, length of stay, and 28-day and 90-day mortality between MRSA-infected patients who received or not received effective antibiotics. Two hundred and eighteen cases received sensitive antibiotics for MRSA.</p><p><b>CONCLUSIONS</b>The MRSA infection rates are at relatively low levels in university teaching hospitals in China. The empirical use of sensitive antibiotics for MRSA infection was at relatively high rate, and there is a tendency of overusing in patients without MRSA infection. On the other hand, the rate of appropriate empirical antibiotic therapy for patients with MRSA infection is relatively low.</p>

Impact of imipenem treatment on colonic mycobiota in rats with double-hit sepsis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Broad-spectrum antibiotic administration promotes intestinal colonization of exogenous fungal pathogens in healthy animals and has been recognized as one of the risk factors of invasive fungal infection in clinical settings. It is unclear whether broad-spectrum antibiotic treatment would change the intestinal mycobiota without exogenous fungal challenge in the context of sepsis.</p><p><b>METHODS</b>We established a rat model of double-hit sepsis using burn injury and endotoxin challenge. Rats with burn injury or double-hit sepsis received imipenem treatment for 3 days or 9 days, and their colon contents were sampled for selective fungal culture and isolation counts.</p><p><b>RESULTS</b>Imipenem treatment promoted the overgrowth of the commensal fungus Geotrichum capitatum in rats with burn injury. Imipenem treatment also promoted colon colonization by exogenous fungi in rats with burn injury and double-hit sepsis, including Trichosporon cutaneum, Candida albicans, Candida krusei, and Candida glabrata. A longer duration of imipenem treatment had a stronger impact on colon colonization by exogenous fungi.</p><p><b>CONCLUSION</b>Imipenem treatment facilitates the overgrowth of commensal fungi and colonization by exogenous, potentially pathogenic fungi in the colons of rats with burn injury or double-hit sepsis.</p>