[Analysis of the risk factors of persistent inflammation-immunosuppression-catabolism syndrome in patients with extensive burns]

Objective: To investigate the risk factors and treatment outcome of persistent inflammation-immunosuppression-catabolism syndrome (PICS) in patients with extensive burns. Methods: A retrospective case series study was conducted. From January 2017 to December 2021, 220 patients with extensive burns who were admitted to Guangzhou Red Cross Hospital of Jinan University met the inclusion criteria, including 168 males and 52 females, aged 18-84 (43±14) years. According to the occurrence of PICS, the patients were divided into PICS group (84 patients) and non-PICS group (136 patients). The general data such as sex, age, complication of underlying diseases and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score on admission, sepsis-related organ failure evaluation (SOFA) scores on admission and 14 days post admission, and proportion of patients with mechanical ventilation over 48 h during treatment, special conditions such as total burn area, full-thickness burn area, proportion of patients admitted within 48 h post injury, and exposed deep wound area at the 30th day post injury, outcome indicators such as hospitalization day, total cost of hospital stay, number of surgeries, and death of patients in the 2 groups were collected and analyzed. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, and chi-square test. The multivariate logistic regression analysis was performed on the indicators with statistically significant differences between the two groups except for outcome indicators, and the independent risk factors influencing secondary PICS in patients with extensive burns were screened. Results: The APACHE Ⅱ and SOFA scores on admission, and proportion of patients with mechanical ventilation over 48 h during treatment of patients in PICS group were significantly higher than those in non-PICS group (t=6.78, Z=-4.75, χ2=4.74, respectively, P<0.05). There were no statistically significant differences in the rest of general data of patients between the two groups (P>0.05). The total burn area, full-thickness burn area, and exposed deep wound area at the 30th day post injury in PICS group were significantly greater than those in non-PICS group (t=6.29, Z=-7.25, Z=-8.73, P<0.05), the exposed deep wound areas at the 30th day post injury in PICS group and non-PICS group were respectively 25% (15%, 35%) total body surface area (TBSA) and 8% (0, 13%) TBSA, while the proportion of patients admitted within 48 h post injury was significantly lower than that in non-PICS group (χ2=6.13, P<0.05). The hospitalization day, total cost of hospital stay, and number of surgeries of patients in PICS group were significantly higher than those in non-PICS group (with Z values of -7.12, -8.48, and -6.87, respectively, P<0.05), while the deaths of patients in the 2 groups were similar (P>0.05). The APACHE Ⅱ score on admission and exposed deep wound area at the 30th day post injury both were the independent risk factors for PICS in patients with extensive burns (with odds ratios of 1.15 and 1.07, 95% confidence intervals of 1.06-1.25 and 1.05-1.10, respectively, P<0.05). Conclusions: The APACHE Ⅱ score on admission and exposed deep wound area at the 30th day post injury are the independent risk factors for PICS in patients with extensive burns. The patients with secondary PICS had good prognosis with more surgical intervention and hospitalization day, and higher total cost of hospital stay.

[Analysis of the clinical characteristics and risk factors of postoperative atrial fibrillation in patients with critical burns]

Objective: To investigate the clinical characteristics and risk factors of postoperative atrial fibrillation (POAF) in patients with critical burns. Methods: A retrospective case series study was conducted. From January 2017 to December 2021, two hundred and twenty-seven critically burned aldult patients who met the inclusion criteria were admitted to Guangzhou Red Cross Hospital of Jinan University, including 173 males and 54 females, aged 19-83 (43±14) years. The admission years of patients were collected, and the percentage of patients complicated with POAF in each year was calculated. According to whether the patients were complicated with POAF or not, they were divided into POAF group (n=17) and non-POAF group (n=210). Following data were collected in patients in POAF group, including operation methods, duration of operation, intraoperative blood loss before occurrence of POAF each time, occurrence time and times of POAF, postoperative body temperature, blood pressure, hemoglobin, blood glucose, blood lactate, sepsis, and electrolyte, and type, duration, and treatment of POAF. General data of patients in the two groups including age, gender, burn reason, total burn area, full-thickness burn area, acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) and sepsis-related organ failure evaluation (SOFA) scores on admission, combined with underlying diseases (hypertension, diabetes, and other types of arrhythmias), and sepsis were collected and analyzed. The mortality and factors influencing the prognosis of patients in the two groups such as mechanical ventilation time, operations times, and burn intensive care unit (BICU) length of stay were also collected and analyzed. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, chi-square test or Kruskal-Wallis H test. The multivariate logistic regression analysis was performed on the general data with statistically significant differences between the two groups, and the independent risk factors influencing the onset of POAF in 227 patients with critical burns were screened. Results: From 2017 to 2021, the percentage of critically burned patients complicated with POAF increased year by year. In POAF group, eschar debridement in limbs was the main surgical procedure prior to POAF complication, with the operation time of (3.5±1.2) h and the intraoperative blood loss volume of (365±148) mL.The POAF occurred 25 times in total in patients of POAF group, mostly within one week after the injury and within 6 hours after the operation with most of these patients having POAF only once. When POAF happened, the patients were often complicated with hypothermia, anemia, hyperglycemia, high blood lactate, sepsis, and electrolyte disturbance, and few patients had complications of hypotension. The POAF lasted (5±3) h, with all being paroxysmal atrial fibrillation, and most of POAF patients were reverted to sinus rhythm after amiodarone intervention. Most patients in the two groups suffered from flame burn, and the gender, age, and SOFA score on admission of patients in the two groups were similar (P>0.05); the APACHEⅡ score on admission, total burn area, full-thickness burn area, incidence proportion of sepsis, combined with diabetes and hypertension and other types of arrhythmias of patients in POAF group were significantly higher or larger than those in non-POAF group (t=3.47, with χ2 values of 7.44, 10.86, 12.63, 14.65, 6.49, and 7.52, respectively, P<0.05 or P<0.01). The full-thickness burn area, combined with other types of arrhythmias, and sepsis were the independent risk factors for POAF in 227 critically burned patients (with odds ratios of 4.45, 0.04, and 3.06, respectively, with 95% confidence intervals of 2.23-8.87, 0.01-0.22, and 1.77-5.30, respectively, P<0.01). Compared with those in non-POAF group, the mechanical ventilation time, BICU length of stay, number of operations, and mortality rate of patients in POAF group were significantly increased (Z=3.89, Z=2.57, t=3.41, χ2=3.72, P<0.05 or P<0.01). Conclusions: POAF is a common postoperative complication in critically burned patients, and the incidence is increasing year by year, which seriously affects the prognosis of patients. The full-thickness burn area together with other types of arrhythmias and sepsis are the high-risk factors for POAF complication in patients with critical burns.

Effect of Ag underlayer on microstructures and perpendicular magnetic properties of CoPt nanocomposite thin films

CoPt/Ag films were prepared by magnetron sputtering on glass substrates and subsequent annealing. The dependence of degree of ordering and magnetic properties on Ag film thickness and annealing conditions were investigated. It was found that the Ag underlayer played a dominant role in inducing the (001) texture of the CoPt film after annealing. CoPt films with a thickness about 20 nm and Ag underlayers with a thickness about 70 nm are easy to obtain a large degree of ordering and a perpendicular magnetic anisotropy after annealing at 700 degrees C for 30 min. CoPt/Ag films with out-of-plane coercivity (Hc (perpendicular)) in the range of 13.5-14.0 kOe and a out-of-plane squareness (S(perpendicular)) of 0.97 were obtained after annealing at 700 degrees C for 30 min. Ag underlayer is beneficial to enhance the Hc(perpendicular)and S(perpendicular) of CoPt film significantly. The degree of ordering and perpendicular magnetic properties of the CoPt films which deposited on Ag underlayer are larger than those of the single layer CoPt films.

Crystallization mechanisms of phase change (GeSbSn)(100-x)Co(x) optical recording films

In this study, the (GeSbSn)(100-x0Co(x) films (x = 0-13.3) were deposited on natural oxidized silicon wafer and glass substrate by dc magnetron co-sputtering of GeSbSn and Co targets. The ZnS-SiO2 films were used as protective layers. The thicknesses of the (GeSbSn)(100-x)Co(x) films and protective layer were 100 nm and 30 nm, respectively. We investigated the effects of Co addition on the thermal property, crystallization kinetics, and crystallization mechanism of the GeSbSn recording film. The crystallization temperatures of (GeSbSn)(100-x)Co(x) films were decreased with Co content. It was found that the activation energy of the (GeSbSn)(100-x)Co(x) films will decrease from 1.53 eV to 0.55 eV as Co content increased from 0 at.% to 13.3 at.%.

Microstructure and crystallization kinetics analysis of the (In15Sb85)(100-x)Zn(x) phase change recording thin films

The (In15Sb85)(100-x)Zn(x) films (x = 0 - 17.4) were deposited on nature oxidized Si wafer and glass substrate at room temperature by magnetron co-sputtering of Sb target and InZn composite target. The thermal property of the films was examined by a homemade reflectivity thermal analyzer. Microstructures of the films were analyzed by transmission electron microscope (TEM). We examined the effects of Zn addition on the thermal property, crystallization kinetics, and crystallization mechanism of the In15Sb85 recording film. As x = 0 - 17.4, thermal analysis shows that the (In15Sb85)(100-x)Zn(x) films have two phase transition temperature ranges which are 189 degrees C-215 degrees C and 300 degrees C-350 degrees C. It is found that the activation energy is increased with Zn content. This indicates that the thermal stability of amorphous state is improved by doping Zn. The optical contrasts of the films are all larger than 15%, as x = 0 - 6.2, indicating that the films have the potential in blue laser optical recording media application.

[Chemical constituents in volatile oil from fruits of Alpinia oxyphylla Miq]

OBJECTIVE

To study the chemical constituents in the volatile oil from fruits of Alpinia oxyphylla.

METHOD

Using GC-MS to identify the constituents.

RESULT AND CONCLUSION

Sixty-four compounds were identified on the basis of GC-MS, the main ones being p-cymene, valence, linalool, myrtenal, alpha-pinene, beta-pinene, furopelargone A and terpinen-4-ol. Three sesquiterpenes valencene, nootkanone and nootkanol have been isolated from the CHCl3 extract as check, of these 64 identified compounds linalyl oxide, valencene, bakkenolide A, furopelargone A and 3-hydroxycalamenene are reported for the first time.

Dynamics of renal histamine in normal rat kidney and in nephrosis induced by aminonucleoside of puromycin

Histamine is known to have a profound effect on capillary permeability in nonrenal tissues and this effect is presumably mediated by cyclic (c)AMP. Because in our previous experiments we found that histamine stimulates cAMP accumulation in glomeruli (Torres, V. E., T. E. Northryn, R. M. Edwards, S. V. Shah, and T. P. Dousa. 1978. Modulation of cyclic nucleotides in isolated rat glomeruli. J. Clin. Invest.62: 1334.), we now explored whether this amine is formed in renal tissue, namely in glomeruli, and whether its renal metabolism is altered in experimental nephrosis induced by puromycin aminonucleoside (PA) in rats. In normal rats, histamine content was higher (Delta + 240%) in cortex than in medulla. In glomeruli isolated from renal cortex, histamine content was significantly higher (Delta + 260%) than in tubules. Incubation of isolated glomeruli with l-histidine resulted in a time-dependent increase of histamine content in glomeruli, but no change was found in tubules. The increase in glomerular histamine was blocked by the histidine decarboxylase inhibitor bromocresine. In rats with PA nephrosis induced by a single intraperitoneal injection of PA (15 mg/100 g body wt) urinary excretion of histamine was markedly increased (>Delta + 200%), but control rats did not differ from rats with PA nephrosis in urinary excretions of l-histidine and of creatinine. At the peak of proteinuria (day 9 after injection of PA) the plasma level of histamine was slightly elevated, and plasma histidine slightly decreased in animals that developed PA nephrosis. The content of histamine was markedly higher and the level of histidine was significantly lower in the renal cortex of PA-nephrotic rats as compared with controls; PA-nephrotic and control rats did not differ in the content of histidine and histamine in the liver. In addition, the content of histamine was higher in glomeruli isolated from PA-nephrotic rats; lesser difference was found in cortical tubules. The results further indicate that PA-nephrotic rats have higher content of histamine in the renal cortex, predominently in glomeruli with increased urinary histamine excretion. The elevated renal cortical histamine is not due to higher availability of histamine precursor l-histidine. Results thus show that glomeruli are a major site of intrarenal histamine synthesis and accumulation, and also suggest that abnormal renal metabolism of this amine in PA nephrosis may be related, as a cause or as a consequence, to the pathogenesis of this disease.

Activities of lysosomal enzymes in isolated glomeruli. Alterations in experimental nephrosis

To study the role of lysosomal enzymes in glomeruli, we examined specific activities of lysosomal hydrolases in isolated glomeruli and, for comparison in isolated tubules, from rat kidney cortex of normal animals and animals with puromycin aminonucleoside nephrosis (PAN). Nephrotic syndrome was induced in rats by a single intraperitoneal injection of aminonucleoside and the rats were sacrificed at the time of peak proteinuria. Colloidal iron staining of renal cortex demonstrated decreased staining for the epithelial polyanion in animals with PAN. Lysosomal enzymes were determined by fluorogenic and colorimetric methods. In normal kidney, total specific activities of cathepsin beta 1, beta-2-fucosidase, acetyl-beta-glucosaminidase, and arylsulfatase were lower in glomeruli compared with tubules and with tissue slices of the same kidney. Total activity of acid phosphatase was higher in glomeruli than tubules. In glomeruli of PAN rats, there were lower activities of N-acetyl-beta-glucosaminidase, D-fucosidase, beta-glucosidase, beta-glucoronidase, and arylsulfatase compared with control rats. Activity of acid phosphatase, on the other hand, was higher in glomeruli of PAN than control rats. All differences were statistically significant. These studies demonstrate that (1) activities of lysosomal enzymes in normal glomeruli and in glomeruli of nephrotic rats have a property distinct from the rest of the kidney, and (2) the specific activities of lysosomal hydrolases are altered in glomeruli of rats with PAN. These studies suggest that changes in activities of lysosomal enzymes may be related to pathogenesis of this glomerulopathy.

Glomerular lysosomal enzymes in aminonucleoside nephrosis

Lysosomal hydrolases produce degradation of glomerular basement membrane and may play a key role in catabolism of glycoproteins of extracellular matrix in glomeruli. Therefore we investigated activities of some lysosomal enzymes and stability of lysosomes in glomeruli of normal and nephrotic rats. Nephrosis was induced in rats by single injections of puromycin aminonucleoside. In glomeruli from nephrotic rats we found lower activities of beta-fucosidase and arylsulfatase, but activity of acid phosphatase was higher compared with control rats. Osmotic stability of lysosomes measured by release of beta-glucuronidase was decreased in nephrotic rats. Abnormal activity of lysosomal enzymes and altered physiology of lysosomes in glomeruli may be a pathogenic factor in the altered glycoprotein metabolism in nephrotic syndrome and perhaps also in other glomerular diseases.