[Analysis of the correlative factors of long-term positive nucleic acid and the characteristics of nucleic acid conversion in novel coronavirus infected patients].

To analyze the correlative factors of long-term positive nucleic acid and the characteristics of negative nucleic acid conversion in novel coronavirus infected patients.Novel coronavirus infected patients who were hospitalized in Beijing Tsinghua Changgung Hospital from December 2022 to June 2023 were retrospectively included. Patients who were positive for novel coronavirus nucleic acid for ≥30 days were selected as the long-positive group, and age-and sex-matched patients with novel coronavirus nucleic acid for <30 days were selected as the control group. The clinical data of all enrolled patients were collected. Binary logistic regression was used to analyze the influencing factors of the positive duration of nucleic acid ≥30 days. The Cox risk ratio model was used to analyze the risk factors for the prognosis of severe patients during hospitalization, and the difference in the time of nucleic acid conversion between the upper and lower respiratory tract was compared between the groups. A total of 30 patients were included in the long-positive group, including 24 males and 6 females, aged [M (Q1, Q3)] 77 (64, 86) years. Fifty-eight patients were included in the control group, including 46 males and 12 females, aged 78 (66, 86) years. Transplantation status (OR=50.32, 95%CI: 1.98-1 278.63, P=0.018), malignant tumor (OR=12.85, 95%CI: 1.65-99.88, P=0.015), CD4+T cell count (OR=0.99, 95%CI: 0.99-1.00, P=0.005) were correlative factors for positive nucleic acid≥30 days. Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score (HR=1.12, 95%CI: 1.03-1.22, P=0.012) and nucleic acid positive time (HR=1.16, 95%CI: 1.01-1.33, P=0.031) were correlative factors for death in severe patients. The nucleic acid conversion time of the lower respiratory tract specimens in both groups was later than that of the upper respiratory tract specimens (all P<0.001). Weakened underlying immunity is a correlative factor for long-term novel coronavirus nucleic acid positivity, and long-term positive novel coronavirus nucleic acid in severe patients indicates high risk of death. The nucleic acid of the lower respiratory tract specimen turned negative later than the upper respiratory tract specimen.

[The expression and clinical significance of serum soluble programmed cell death ligand-1 in adult patients with community-acquired pneumonia].

To investigate the clinical significance of serum soluble programmed cell death ligand-1 (PD-L1) in adult patients with community-acquired pneumonia (CAP). A total of 44 CAP patients, 54 severe CAP patients and 30 healthy volunteers were recruited in this study. Serum soluble PD-L1 were detected. Univariate and multivariate regression analyses were used to assess the influence of multiple clinical variables on prognosis. Serum soluble PD-L1 level in severe CAP group was 98.20(57.94, 128.90) ng/L, which was significantly higher than that in the CAP group [59.32(33.55, 92.58) ng/L] and healthy controls [20.44(12.15, 36.20) ng/L] (all P<0.001). PD-L1 level was positively correlated with CRUB-65(r=0.481, P<0.001) and the pneumonia severity index (PSI) score (r=0.442, P<0.001). Univariate regression analysis showed that CURB-65 (HR=2.544, 95%CI 1.324-4.889, P=0.005), PSI score (HR=1.036, 95%CI 1.012-1.061, P=0.004), soluble PD-L1(HR=1.013, 95%CI 1.001-1.026, P=0.041) were risk factors of mortality during hospitalization. Multivariate regression analysis suggested that PSI score (HR=1.042, 95%CI 1.012-1.073, P=0.005), soluble PD-L1 (HR=1.011, 95%CI 1.002-1.071, P=0.020) were independent predictors for mortality risk in CAP patients. CAP patients with soluble PD-L1≥98.20 ng/L had a significantly lower survival rate than those with soluble PD-L1<98.20 ng/L (P=0.033). In conclusion, this study indicates that serum soluble PD-L1 level in CAP patients is correlated with the survival prognosis.

[Expression and clinical significance of CCL18 in bronchoalveolar lavage fluid of connective tissue disease-associated interstitial lung disease].

Objective: To explore the expression and clinical significance of chemokine ligand 18 (CCL18) in Bronchoalveolar Lavage Fluid (BALF) of patients with connective tissue disease-associated interstitial lung disease (CTD-ILD). Methods: From January 2016 to June 2017, BALF of patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD group), patients with dermatomyositis-associated interstitial lung disease (DM-ILD group), and patients with primary Sjögren syndrome-associated interstitial lung disease (pSS-ILD group) of Peking University People's Hospital were collected. According to the prognosis of each group of patients during hospitalization, they were divided into the discharged and the died. Besides, 30 patients without ILD served as a control group. Levels of CCL18 in BALF of all patients were tested by enzyme linked immunosorbent assay (ELISA). Cells in BALF of RA-ILD group, DM-ILD group and pSS-ILD group were collected and analyzed by absolute different cell counts. Results of high-resolution CT (HRCT) of these three groups were scored. In addition, the area under the curve (AUC) of CCL18 in predicting mortality during hospitalization was calculated. Results: A total of 38 patients with RA-ILD, 54 patients with DM-ILD, and 35 patients with pSS-ILD were enrolled. Levels of CCL18 of those discharged patients of RA-ILD, DM-ILD, and pSS-ILD groups were 8.27(3.62, 14.36), 11.04 (5.86, 17.38), 5.25(2.68, 8.21) µg/L, respectively, which were all significantly higher than that of the control group [2.54(1.26, 3.66) µg/L, all P<0.05]. Furthermore, levels of CCL18 of those deceased patients of RA-ILD and DM-ILD groups were 18.28 (13.82, 22.39), 18.81 (16.29, 22.90) µg/L, which were significantly higher than that of the discharged patients of same group (all P<0.05). Levels of CCL18 were positively correlated with lymphocyte percentage in BALF of RA-ILD, DM-ILD and pSS-ILD groups (r=0.4356, 0.4029, 0.3939, respectively, all P<0.05). Besides, levels of CCL18 were significantly correlated with HRCT scores of RA-ILD and DM-ILD groups (r=0.4242, 0.3319, respectively, both P<0.05). Areas under the curve (AUCs) of CCL18 to predict mortality during hospitalization of RA-ILD and DM-ILD groups were 0.860, 0.851, respectively. Conclusions: Levels of CCL18 are elevated in BALF of CTD-ILD patients, and may be correlated with the severity and prognosis during hospitalization. CCL18 might be served as an indicator of the severity and prognosis of CTD-ILD.

[Effects of artesunate on cigarette smoke-induced lung oxidative damage in mice and the expression of Nrf2 and the possible mechanism].

OBJECTIVE: To explore the effects of artesunate on cigarette smoke-induced lung oxidative damage in mice and the expression of Nuclear factor-E2-related factor 2 (Nrf2). METHODS: In vivo: A total of 40 female specific pathogen free BALB/c mice were divided randomly into four groups: normal group, cigarette smoke group, vehicle group and artesunate group. The latter three groups were exposed on cigarette smoke for 40 days. Vehicle (5% NaHCO3 containing 5% dimethyl sulfoxide, 0.1 ml of each mice) or artesunate (30 mg/kg, dissolved in the 0.1 ml vehicle) was given by intraperitoneal injections before each passive smoking of the vehicle or artesunate group. Saline of 0.1ml was given to the normal and cigarette smoke groups as negative controls. Cells in bronchoalveolar lavage fluid (BALF) were collected and analyzed by absolute different cell counts. Interleukin (IL)-8 levels in BALF and 3-nitrotyrosine (NT) levels in lung tissue were tested by emzyme linked immunosorbent assay (ELISA). Malondialdehyde levels in serum, total superoxide dismutase (SOD) activity and total glutathione peroxidase (GPx) activity in lung tissue were detected. The pathological changes of lung tissues were observed by HE staining. And the expression levels of Nrf2 were measured by Westernblotting. In vitro: 16HBE cells were cultured and transfected with Nrf2 siRNA. Cigarette smoke extract (CSE) were used to stimulate the secretion of IL-8 in cells. Cells were divided into five groups: blank group, non-transfected non-artesunate group, non-transfected artesunate group, transfected non-artesunate group and transfected artesunate group. The latter four groups were incubated with CSE, and non-transfected artesunate and transfected artesunate groups were intervened with artesunate (30 µmol/L) before CSE incubation. The IL-8 levels of each group were measured using ELISA kit. RESULTS: In vivo: The total cell counts of BALF in artesunate group were significantly lower than the vehicle group [21.00(2.50)×10(4)/ml vs 35.50(2.50)×10(4)/ml, P<0.001], especially neutrophil counts [6.00(5.12)×10(4)/ml vs 13.60(5.25)×10(4)/ml, P<0.001]. The IL-8 levels in BALF, malondialdehyde levels in serum, 3-NT levels and total SOD activity in lung tissue of artesunate group were all drastically lower than those in the vehicle group [(508±55) vs (912±68) ng/L, (38.2±8.8) vs (48.7±10.6) µmol/L, (28.5±5.8) vs (50.0±9.7) µg/L and (11.8±1.8) vs (18.0±5.3) U/mg protein, respectively, all P<0.05]. No significant difference of total GPx activity existed in these four groups. And the expression level of Nrf2 in artesunate group significantly increased than that in vehicle group (P=0.008). In vitro: The IL-8 level of the non-transfected artesunate group was significantly lower than the non-transfected non-artesunate group [(352±26) vs (765±22) ng/L, P<0.001], while the IL-8 levels between the transfected artesunate and transfected non-artesunate groups had no significant difference. CONCLUSION: Arteunate attenuates cigarette smoke-induced lung oxidative damage in mice and increases the expression level of Nrf2, and its effects might be mediated by the actions of nuclear Nrf2.

MIC gene polymorphism and haplotype diversity in Li nationality of Southern China.

Here, we report for the first time the polymorphisms of MICA and MICB in a healthy Li population of 344 unrelated individuals. By using polymerase chain reaction-sequence specific priming (PCR-SSP) and sequence-based typing (PCR-SBT), 17 MICA-sequence alleles and 5 MICA-STR (short tandem repeats, STR) alleles, as well as 17 MICB alleles were detected, among which MICA*010, MICA*A4 and MICB*005:02 were the most frequent alleles. In addition, linkage disequilibrium was investigated and the most common two-locus haplotypes were MICB*005:02-MICA*010 and MICB*008-MICA*002:01. These results present informative genetic markers for the investigation of possible origins and the evolution of MHC class I haplotypes in the Li population.

Positive association of major histocompatibility complex class I chain-related gene A polymorphism with leukemia susceptibility in the people of Han nationality of Southern China.

To assess the potential contribution of major histocompatibility complex class I chain-related gene A (MICA) polymorphisms toward the pathogenesis of leukemia, 107 leukemia patients and 162 ethnically matched controls from Hunan province, Southern China, were genotyped for the MICA polymorphism using polymerase chain reaction-sequence-specific priming (PCR-SSP) and sequence-based typing (PCR-SBT). The relevance between these genotypes and risk of leukemia was assessed by means of odds ratio (OR) with 95% confidence intervals (95% CIs). Allele frequencies of MICA-sequence and MICA-STR were different in leukemia patients in comparison with normal controls (both P < 0.05). MICA A5 was directly associated with leukemia (OR = 2.3257, Pc < 0.0005), whereas MICA A5.1 and MICA*008 were inversely associated with leukemia (OR = 0.5874, Pc = 0.0235 and OR = 0.5874, Pc = 0.0329, respectively). In addition, we found that homozygotes for MICA A5 (OR = 14.0659, 95% CI: 3.1627-62.5574, Pc < 0.0001) and MICA*010 (OR = 10.1053, 95% CI: 2.2139-46.1260, Pc < 0.0004) were at an increased risk for leukemia, whereas heterozygotes for MICA*008 and MICA A5.1 were linked to a decreased risk for leukemia (OR = 0.4609, 95% CI: 0.2799-0.7590, Pc = 0.0027). MICA allelic variation is associated with leukemia in Hunan Han population; the data also suggest that MICA gene polymorphism affects susceptibility to different clinical subtypes of leukemia.

[Clinical application of extracorporeal membrane oxygenation in the treatment of burn patients with acute respiratory distress syndrome: a retrospective analysis and systematic review].

Objective: To analyze the clinical effect of extracorporeal membrane oxygenation (ECMO) in the treatment of burn patients with acute respiratory distress syndrome (ARDS). Methods: The retrospective observational study and the systematic review were applied. From March 2014 to July 2020, five burn patients with ARDS received ECMO treatment in the First Affiliated Hospital of Army Medical University (the Third Military Medical University). All the five patients were male, aged from 40 to 62 years. The average total burn surface area was 58.8% total body surface area (TBSA) and four cases had severe inhalation injury. Patient's ECMO starting time, duration and mode, and whether successfully weaned or the cause of death, and others. were recorded. Furthermore, the changes of oxygenation and infection before, during, and after utilizing ECMO were analyzed. PubMed and Web of Science from the establishment of each database to August 2021 were searched using "Extracorporeal Membrane Oxygenation", "ECMO", "burn", "inhalation" as the search terms and "Title/Abstract" as the field to retrieve the clinical articles that meet the selection criteria . Basic information were extracted from the articles, including sample size, gender, age, total burn area, inhalation injury, the indication of ECMO, the start and lasting time of ECMO, ECMO mode, rate of successful weaning, complications of ECMO, mortality, the combined application of continuous renal replacement therapy (CRRT). Results: Five patients started venovenous ECMO on an average of 10.2 days after injury and lasted an average of 180.4 hours. Three out of 5 patients were weaned successfully with one patient survived. Four patients died of multiple organ dysfunction syndrome (MODS) and septic shock. Compared with those before ECMO treatment, the arterial oxygen partial pressure (PaO2) and oxygen saturation in arterial blood (SaO2) of three successfully weaned patients obviously increased during and after ECMO treatment. The fraction of inspired oxygen (FiO2) decreased below 50% and PaO2/FiO2 ratio increased above 200 mmHg (1 mmHg=0.133 kPa) during and after ECMO. Furthermore, lactic acid and respiratory rate decreased, basically. Compared with those before ECMO, PaO2 and SaO2 in the other two patients during ECMO, who failed to be weaned, continuously decreased while lactic acid increased. Before and during ECMO, the PaO2/FiO2 ratios of unsuccessfullg weaned cases were less than 200 mmHg, and partial pressure of carbon dioxide in arterial blood (PaCO2) were more than 40 mmHg. Compared with those before ECMO, there were no significant changes in body temperature during and after ECMO, which were less than 38 ℃. Compared with those before ECMO, the leucocyte number (the index without this in unsuccessfully weaned cases was omitted, the same as below) in four patients showed a significant decrease during ECMO, but rose after removal of ECMO. The proportion of neutrophils in three patients were slightly higher during ECMO than before ECMO, and did not change significantly after removal of ECMO. Compared with those before ECMO, platelet counts in three patients were significantly reduced during ECMO, and all five patients during ECMO were below normal levels. Compared with those before ECMO, the procalcitonin levels in four deaths were significantly increased during ECMO. Catheter culture of microorganism was performed in three successfully weaned patients, all of which were negative. A total of 13 literature were included, ranging from 1990 to 2019. The sample size in 6 studies was less than 10, and the sample size in 4 studies was between 10 and 20, and only 2 literatures had a sample size larger than 50. ECMO was applied in 295 burn patients with overall mortality of 48.8% (144/295), including 157 adults and 138 children. The most common indication of ECMO was severe ARDS. Among 157 adult burn patients (95 males and 65 females), 36 cases had inhalation injury. The average burn area was 27%-37%TBSA in 5 reported studies and was more than 50%TBSA in 2 reported studies. The most common mode was venovenous ECMO. ECMO treatment began 26.5 hours to 7.4 days after injury and lasted from 90 hours to 18 days, and the rate of successful weaning ranged from 50% to 100%. The most common complications were bleeding and infection. The mortality was 52.9% (83/157). MODS and sepsis were the leading causes of death. Among 138 pediatric burn patients (77 boys and 61 girls), 29 patients had inhalation injury. The average burn area was 17%-50.2%TBSA in 3 studies. ECMO treatment lasted from 165.2 hours to 324.4 hours. Bleeding was the most common complication. The mortality was 44.2% (61/138). Conclusions: ECMO is an effective strategy for the salvage treatment of burns complicated with ARDS. Furthermore, the prevention and treatment of bleeding, infection and organ dysfunction should be emphasized during the use of ECMO. More importantly, evidence-based guidelines for burns are urgently needed to further improve the clinical effect of ECMO.

[Establishment of nomogram predicting model for the death risk of extremely severe burn patients and the predictive value].

Objective: To explore the death risk factors of extremely severe burn patients, establish a death risk nomogram predicting model, and investigate the predictive value for death risk of extremely severe burn patients. Methods: The medical records of 231 extremely severe burn patients (190 males and 41 females, aged 18-60 years) who were admitted to the Institute of Burn Research of the First Affiliated Hospital of Army Medical University from January 2010 to October 2018 and met the inclusion criteria were analyzed retrospectively. According to the final outcome, the patients were divided into survival group of 173 patients and death group of 58 patients. The sex, age, severity of inhalation injury, total burn area, full-thickness burn area, burn index, rehydration coefficient and urine volume coefficient of the first and second 24 h after injury, the first base excess, shock index, and hematocrit (HCT) after admission, whether to have pre-hospital fluid infusion, use of ventilator, and use of continuous renal replacement therapy (CRRT), and abbreviated burn severity index (ABSI ) and Baux score on admission of patients in the two groups were recorded or calculated. According to the use of ventilator, the patients were divided into with ventilator group of 131 patients and without ventilator group of 100 patients, and the death, total burn surface area, burn index, incidence and severity of inhalation injury were recorded. According to the use of CRRT, the patients were divided into with CRRT group of 59 patients and without CRRT group of 172 patients, and the death, total burn surface area, and burn index were recorded. Data were statistically analyzed with t test, chi-square test, and Mann-Whitney U test to screen the death related factors of patients. The indexes with statistically significant differences between survival group and death group were included in the multivariate logistic regression analysis to screen the independent death risk factors of patients, and the death risk nomogram predicting model was constructed based on the results.The Bootstrap method was used to validate the death risk nomogram predicting model internally. The predictive value of the nomogram model for predicting death risk of patients was detected by drawing calibration graph and calculating concordance index, and the death risk scores of 231 patients were acquired according to the death risk nomogram model. The receiver's operating characteristic (ROC) curve was drawn, and the optimal threshold and the sensitivity and specificity of optimal threshold in the ROC curve and the area under the curve were calculated. Results: (1) There were statistically significant differences in burn index, ABSI on admission, severity of inhalation injury, total burn area, full-thickness burn area, rehydration coefficient at the first 24 h after injury, use of ventilator, use of CRRT, and Baux score on admission of patients between the two groups (Z=-7.696, -7.031, χ(2)=18.304, 63.065, 23.300, 13.073, 34.240, 59.586, t=-7.536, P<0.01). (2) There were statistically significant differences in death, incidence and severity of inhalation injury, total burn area, and burn index of patients between with ventilator group and without ventilator group (χ(2)=34.240, 17.394, 25.479, Z=-6.557, -7.049, P<0.01). (3) There were statistically significant differences in death, total burn area, and burn index of patients between with CRRT group and without CRRT group (χ(2)=62.982, Z= -47.421, -6.678, P<0.01). (4) The use of ventilator, use of CRRT, and burn index were independent risk factors for the death of extremely severe burn patients (odds ratio=3.277, 5.587, 1.067, 95% confidence interval=1.073-10.008, 2.384-13.093, 1.038-1.096, P<0.05 or P<0.01). (5) The initial concordance index of nomogram predicting model was 0.90 and the corrected concordance index was 0.89. The concordance indexes before and after correction were higher and similar, which showed that the nomogram had good concordance and predictive effect. The optimum threshold of ROC curve was 0.23, the sensitivity and specificity of optimum threshold were 86.0% and 80.0%, respectively, and the area under ROC curve was 0.90 (95% confidence interval=0.86-0.94, P<0.01). Conclusions: Severe burns and damage and/or failure of organ are the main death causes of extremely severe burn patients. The death risk nomogram predicting model established on the basis of use of ventilator, use of CRRT, and burn index have good predictive ability for death of extremely severe burn patients.

[Recommendations for normalizing the medical practices of burn treatment during the outbreak of coronavirus disease 2019].

2019 novel coronavirus (2019-nCoV) is one of the beta coronaviruses and is identified as the pathogen of the severe " coronavirus disease 2019 (COVID-19)" in 2019. China manages COVID-19 according to the reguirement of the highest level infectious diseases in China. Currently, the prevention and control of COVID-19 in China is at a critical period. Burn Department as an emergency discipline is confronted with risk of 2019-nCoV infection. Based on the guidelines for the diagnosis and treatment of COVID-19 (6th trial edition), in combination with the latest literature at home and abroad, the features of the COVID-19, the recommendations for the COVID-19 prevention and control issued by the National Health Commission of China, and the management experience of COVID-19 diagnosis and treatment of other related disciplines, we put forward some recommendations for the medical practices of burn treatment during the outbreak of the COVID-19 in outpatient and emergency, inpatient treatment, and the management of operation theatres and wards, etc. We hope these recommendations could benefit the medical professionals in the field of burn treatment and relevant hospital management during the outbreak of COVID-19, improve burn treatment, and avoid or reduce the risk of infection of medical staff.

[Advances in the research of application of urine output monitoring in prevention and treatment of burn shock].

Fluid therapy is a crucial treatment for patients with extensive burn, which affects patients'prognosis directly. Accurate urine output measurement plays an irreplaceable role in guiding fluid resuscitation in clinic. As one of the best indexes in traditional burn resuscitation, urine output comprehensively reflects systemic circulation. However, it doesn't fully reflect all the specific chapters of microcirculation and systemic circulation and deficient cellular oxygen metabolism exactly. We need to use urine output combined with other shock parameters to ensure adequate fluid replacement. Currently, the most common way of urine output monitoring is manual measurement. The article reviews the application of urine output monitoring in guiding fluid resuscitation of burn shock.

[Clinical randomized controlled trial on the feasibility and validity of continuous blood purification during the early stage of severe burn].

OBJECTIVE: To observe and primarily evaluate the feasibility and validity of continuous blood purification (CBP) during the early stage of severe burn. METHODS: Forty-one patients with severe burn admitted to our ward from January 2013 to July 2015, conforming to the study criteria, were divided into conventional treatment group (CT, n=21) and blood purification group (BP, n=20) according to the random number table and patient's personal consent. Patients in group CT received CT conforming to the traditional resuscitation principle for severe burn, while patients in group BP received CT and blood purification treatment in the mode of continuous venous-venous hemodiafiltration in addition up to post injury hour (PIH) 72. On post injury day (PID) 1, 2, 3, the vital signs, volume of fluid input, and volume of the urine output were observed and recorded; femoral artery blood was drawn to determine lactate, bicarbonate radical, and base excess, and oxygen index was calculated. At PIH 12, 24, 48, 72, femoral vein blood was drawn to determine white cell count, platelet count, neutrophils, creatine kinase-MB, creatine kinase, lactic dehydrogenase, aspartate transaminase (AST), alanine aminotransferase (ALT), creatinine, urea nitrogen, and blood glucose (the ratio of AST to ALT was calculated). The incidence of infection, sepsis, and multiple organ dysfunction syndrome (MODS) and the mortality of patients were recorded during 2 months after injury. Data were processed with chi-square test, analysis of variance for repeated measurement, t test and Wilcoxon test, and the values of P were adjusted by Bonferroni. RESULTS: The observation was completed in the 41 patients without exclusion. (1) There were no statistically significant differences in vital signs, volume of fluid input, and volume of the urine output of patients between two groups on PID 1, 2, 3 (with t values from -1.64 to 1.48, P values above 0.05). (2) Compared with that in group CT, the level of lactate of patients in group BP declined significantly on PID 2 and 3 (with Z values respectively -2.37 and -2.46, P values below 0.05). Compared with those in group CT, the levels of bicarbonate radical and base excess of patients in group BP declined significantly on PID 3 (with t values both as -2.51, P values below 0.05). The oxygen index of patients in group BP on PID 3 was (370±98) mmHg (1 mmHg=0.133 kPa), which was significantly higher than that in group CT [(305±81) mmHg, t=2.27, P<0.05]. (3) There were no statistically significant differences in white cell count, platelet count, neutrophils, creatine kinase, lactic dehydrogenase, AST, ALT, and AST to ALT ratio of patients between two groups at PIH 12, 24, 48, 72 (with t values from -1.47 to 1.19, Z values from -1.58 to -0.03, P values above 0.05). At PIH 24, 48, 72, the levels of creatine kinase-MB and blood glucose of patients in group BP were respectively (81±43), (55±34), (58±40) U/L and (7.9±2.0), (6.7±0.9), (6.9±1.8) mmol/L, which were significantly lower than those in group CT [(179±184), (124±71), (103±57) U/L and (10.1±3.8), (9.1±2.4), (8.8±4.1) mmol/L, with Z values from -3.73 to -2.02, P<0.05 or P<0.01]. Compared with those of patients in group CT, creatinine at PIH 48 and urea nitrogen at PIH 24, 48, 72 were obviously lower in group BP (with t values from -4.23 to -2.44, P<0.05 or P<0.01). (4) During the two months after injury, the infection rate of patients in group BP was 60.0% (12/20), which was significantly lower than that in group CT [95.2% (20/21), χ(2)=5.51, P<0.05]. The incidence of sepsis and MODS and the mortality of patients in group BP were all lower than those in group CT, but there were no statistically significant differences (with χ(2) values from 0.22 to 2.93, P values above 0.05). CONCLUSIONS: Conducting CBP in the early stage of severe burn is safe and feasible, which does not obviously affect the vital signs, volumes of fluid input and urine output, or platelet count of patients, additionally, it could help protect the function of vital organs, eliminate stress hyperglycemia, and reduce infection rate. Clinical trial registration Chinese Clinical Trial Registry, ChiCTR-TRC-12002616.

MIC gene polymorphism and haplotype diversity in Zhuang nationality of Southern China.

Zhuang ethnic minority is the largest minority group in China. Here, we report for the first time the polymorphisms of MICA and MICB in a healthy Zhuang population of 209 unrelated individuals. Using polymerase chain reaction-sequence specific priming (PCR-SSP) and sequencing-based typing (PCR-SBT), 13 MICA-sequence alleles and 5 MICA-STR alleles, as well as 11 MICB alleles were detected, among which MICA(∗)010, MICA(∗)A5 and MICB(∗)005:02 were the most frequent alleles. Linkage disequilibria was investigated and the most common two-locus haplotypes were MICB(∗)005:02-MICA(∗)010 and MICB(∗)014-MICA(∗)045. These results suggest informative genetic markers for investigating origins and evolution of MHC class I region haplotypes in Zhuang population.

MICA-STR, HLA-B haplotypic diversity and linkage disequilibrium in the Hunan Han population of southern China.

Major histocompatibility complex (MHC) class I chain-related gene A (MICA) is located 46 kb centromeric to HLA-B and encodes a stress-inducible protein. MICA allelic variation is thought to be associated with disease susceptibility and immune response to transplants. This study was aimed to investigate the haplotypic diversity and linkage disequilibrium between human leukocyte antigen (HLA)-B and (GCT)(n) short tandem repeat in exon 5 of MICA gene (MICA-STR) in a southern Chinese Han population. Fifty-eight randomly selected nuclear families with 183 members including 85 unrelated parental samples were collected in Hunan province, southern China. HLA-B generic typing was performed by polymerase chain reaction-sequence-specific priming (PCR-SSP), and samples showing novel HLA-B-MICA-STR linkage were further typed for HLA-B allelic variation by high-resolution PCR-SSP. MICA-STR allelic variation and MICA gene deletion (MICA*Del) were detected by fluorescent PCR-size sequencing and PCR-SSP. Haplotype was determined through family segregation analysis. Statistical analysis was applied to the data of the 85 unrelated parental samples. Nineteen HLA-B specificities and seven MICA-STR allelic variants were observed in 85 unrelated parental samples, the most predominant of which were HLA-B*46, -B60, -B*13, and -B*15, and MICA*A5, MICA*A5.1 and MICA*A4, respectively. Genotype distributions of HLA-B, MICA-STR loci were consistent with Hardy-Weinberg proportions. The HLA-B-MICA-STR haplotypic phases of all 85 unrelated parental samples were unambiguously assigned, which contained 30 kinds of HLA-B, MICA-STR haplotypic combinations, nine of them have not been reported in the literature. Significant positive linkage disequilibria between certain HLA-B and MICA-STR alleles, including HLA-B*13 and MICA*A4, HLA-B*38 and MICA*A9, HLA-B*58 and MICA*A9, HLA-B*46 and MICA*A5, HLA-B*51 and MICA*A6, HLA-B*52 and MICA*A6, and HLA-B60 and MICA*A5.1, were observed. HLA-B*48 was linked to MICA*A5, MICA*A5.1 and MICA*Del. HLA-B*5801-MICA*A10 linkage was found in a family. Our data indicated a high degree of haplotypic diversity and strong linkage disequilibrium between MICA-STR and HLA-B in a southern Chinese Han population, the data will inform future studies on anthropology, donor-recipient HLA matching in clinical transplantation and HLA-linked disease association.

[Preparation and evaluation of phosphatidylcholine coated on silica as the biomembrane stationary phase].

The method of reverse phase evaporation is used to coat phosphatidylcholine(PC) directly on the surface of silica, which is used as biomembrane chromatographic solid phase to study the interactions between drugs and biomembrane. It was observed that the solid phase coated phosphatidylcholine had a good stability at 20 degrees C-30 degrees C, and the stability would be improved by the presence of appropriate amount of cholesterol in phosphatidylcholine. The content of cholesterol in phosphatidylcholine, the nature of buffer, the concentration of salt in buffer and the pH of mobile phase could all affect chromatographic retention of drugs on the prepared biomembrane column. Six compounds, polyethylene glycol, mannitol, salicylic acid, warfarin, hydrocortisone, and cortisone have been tested. The biomembrane chromatographic stationary phase coated PC with silica as matrices can be simply prepared and it is possible to simulate the human's physiological environment by the biomembrane chromatographic system, so it is a useful method to study drug absorption and distribution in human body.