[Effect and mechanism of human adipose-derived stem cell exosomes on diabetic peripheral neuropathy]

Objective: To investigate the changes of artemin protein expression in diabetic peripheral neuropathy (DPN) and to explore the regulatory effect of human adipose-derived stem cell (ADSC) exosomes on the change of artemin protein expression. Methods: This research was a prospective observational clinical research combined with experimental research. Thirteen DPN patients (9 males and 4 females, aged 32 to 68 years) who were admitted to the First Affiliated Hospital of Air Force Medical University (hereinafter referred to as our hospital) from May 2022 to October 2023 and met the inclusion criteria were selected as DPN group, and 5 non-diabetes patients (4 males and 1 female, aged 29 to 61 years) who were admitted to our hospital in the same period of time and met the inclusion criteria were selected as control group. The toe nerve or sural nerve tissue in the abandoned tissue after debridement or amputation of patients in the two groups was collected. The pathological changes of nerve tissue were observed after hematoxylin-eosin staining; the protein expressions of S100β and artemin in nerve tissue were observed after immunofluorescence staining, and the artemin protein expression was quantified; the protein and mRNA expressions of artemin were detected by Western blotting and real-time fluorescent quantitative reverse transcription polymerase chain reaction, respectively (the sample number in DPN group and control group was 13 and 5, respectively). Twelve male C57BL/6 mice aged 3 to 5 days were collected to isolate Schwann cells, and the cells were divided into conventional culture group cultured routinely, high glucose alone group (cultured with high concentration of glucose solution only), and high glucose+exosome group (cultured with high concentration of glucose solution and extracted human ADSC exosomes). After 24 hours of culture, the cell proliferation activity was detected by cell counting kit 8 (n=6). After 48 hours of culture, the protein expression of artemin was detected by Western blotting (n=3). Results: Compared with those in control group, the neural supporting cells decreased and the inflammatory cells increased in the nerve tissue of patients in DPN group, showing typical manifestations of nerve injury. Immunofluorescence staining showed that compared with those in control group, the nuclei was more, and the protein expression of S100β was lower in nerve tissue of patients in DPN group. The protein expression of artemin in nerve tissue of patients in DPN group was 71±31, which was significantly lower than 1 729±62 in control group (t=76.92, P<0.05). Western blotting detection showed that the protein expression of artemin in nerve tissue of patients in DPN group was 0.74±0.08, which was significantly lower than 0.97±0.06 in control group (t=5.49, P<0.05). The artemin mRNA expression in nerve tissue of patients in DPN group was significantly lower than that in control group (t=7.65, P<0.05). After 24 hours of culture, compared with that in conventional culture group, the proliferation activities of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the proliferation activity of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). After 48 hours of culture, compared with those in conventional culture group, the protein expressions of artemin of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the protein expression of artemin of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). Conclusions: The protein expression of artemin in nerve tissue of DPN patients is lower than that in normal nerve tissue, which may be related to the reduction of proliferation activity of Schwann cells by high glucose. Human ADSC exosomes may improve the proliferation activity of Schwann cells by increasing artemin protein expression, thereby delaying the progression of DPN.

[Influences and mechanism of extracellular vesicles from dermal papilla cells of mice on human hypertrophic scar fibroblasts]

Objective: To investigate the influences and mechanism of extracellular vesicles from dermal papilla cells (DPC-EVs) of mice on human hypertrophic scar fibroblasts (HSFs). Methods: The study was an experimental research. The primary dermal papilla cells (DPCs) of whiskers were extracted from 10 6-week-old male C57BL/6J mice and identified successfully. The DPC-EVs were extracted from the 3rd to 5th passage DPCs by ultracentrifugation, and the morphology was observed through transmission electron microscope and the particle diameter was detected by nanoparticle tracking analyzer (n=3) at 24 h after culture. The 3rd passage of HSFs were divided into DPC-EV group and phosphate buffer solution (PBS) group, which were cultured with DPC-EVs and PBS, respectively. The cell scratch test was performed and cell migration rate at 24 h after scratching was calculated (n=5). The cell proliferation levels at 0 (after 12 h of starvation treatment and before adding DPC-EVs or PBS), 24, 48, 72, and 96 h after culture were detected by using cell counting kit 8 (n=4). The protein expressions of α-smooth muscle actin (α-SMA) and collagen typeⅠ (ColⅠ) in cells at 24 h after culture were detected by immunofluorescence method and Western blotting, and the protein expression of Krüppel-like factor 4 (KLF4) in cells at 24 h after culture was detected by Western blotting. After the 3rd passage of HSFs were cultured with DPC-EVs for 24 h, the cells were divided into blank control group, KLF4 knockdown group, and KLF4 overexpression group according to the random number table. The cells in blank control group were only routinely cultured for 48 h. The cells in KLF4 knockdown group and KLF4 overexpression group were incubated with KLF4 knockdown virus for 24 h, then the cells in KLF4 knockdown group were routinely cultured for 24 h while the cells in KLF4 overexpression group were incubated with KLF4 overexpression virus for 24 h. The protein expressions of KLF4, α-SMA, and ColⅠ in cells were detected by Western blotting at 48 h after culture. Results: At 24 h after culture, the extracted DPC-EVs showed vesicular structure with an average particle diameter of 108.8 nm. At 24 h after scratching, the migration rate of HSFs in PBS group was (54±10)%, which was significantly higher than (29±8)% in DPC-EV group (t=4.37, P<0.05). At 48, 72, and 96 h after culture, the proliferation levels of HSFs in DPC-EV group were significantly lower than those in PBS group (with t values of 4.06, 5.76, and 6.41, respectively, P<0.05). At 24 h after culture, the protein expressions of α-SMA and ColⅠ of HSFs in DPC-EV group were significantly lower than those in PBS group, while the protein expression of KLF4 was significantly higher than that in PBS group. At 48 h after culture, compared with those in blank control group, the protein expression of KLF4 of HSFs in KLF4 knockdown group was down-regulated, while the protein expressions of α-SMA and ColⅠ were both up-regulated; compared with those in KLF4 knockdown group, the protein expression of KLF4 of HSFs in KLF4 overexpression group was up-regulated, while the protein expressions of ColⅠ and α-SMA were down-regulated. Conclusions: The DPC-EVs of mice can inhibit the proliferation and migration of human HSFs and significantly inhibit the expressions of fibrosis markers α-SMA and ColⅠ in human HSFs by activating KLF4.

Rapid and accurate identification of bacteria utilizing laser-induced breakdown spectroscopy

Timely and accurate identification of harmful bacterial species in the environment is paramount for preventing the spread of diseases and ensuring food safety. In this study, laser-induced breakdown spectroscopy technology was utilized, combined with four machine learning methods - KNN, PCA-KNN, RF, and SVM, to conduct classification and identification research on 7 different types of bacteria, adhering to various substrate materials. The experimental results showed that despite the nearly identical elemental composition of these bacteria, differences in the intensity of elemental spectral lines provide crucial information for identification of bacteria. Under conditions of high-purity aluminum substrate, the identification rates of the four modeling methods reached 74.91%, 84.05%, 85.36%, and 96.07%, respectively. In contrast, under graphite substrate conditions, the corresponding identification rates reached 96.87%, 98.11%, 98.93%, and 100%. Graphite is found to be more suitable as a substrate material for bacterial classification, attributed to the fact that more characteristic spectral lines are excited in bacteria under graphite substrate conditions. Additionally, the emission spectral lines of graphite itself are relatively scarce, resulting in less interference with other elemental spectral lines of bacteria. Meanwhile, SVM exhibited the highest precision rate and recall rate, reaching up to 1, making it the most effective classification method in this experiment. This study provides a valuable approach for the rapid and accurate identification of bacterial species based on LIBS, as well as substrate selection, enhancing efficient microbial identification capabilities in fields related to social security and military applications.

[Perioperative management of wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy and its clinical effects]

Objective: To investigate the perioperative management of wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy, and to evaluate its clinical effects. Methods: This study was a retrospective observational study. From January 2017 to December 2022, 36 patients with wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy who were conformed to the inclusion criteria were admitted to the Burn Center of PLA of the First Affiliated Hospital of Air Force Medical University, including 23 males and 13 females, aged 25 to 81 years. Preparation for surgery was made. For patients with suspected retrosternal mediastinal abscess cavity, all cancellous bone of the unhealed sternum was bitten off to fully expose the retrosternal mediastinum, remove the source of infection and granulation tissue, and to fill the sternum defect with flipped unilateral pectoralis major muscle. For patients who had no retrosternal mediastinal infection but had fresh granulation tissue in unhealed sternal wounds, the necrotic tissue and a small amount of necrotic sternum were palliatively removed, and bilateral pectoralis major muscles were advanced and abutted to cover the sternal defect. After the skin in the donor area was closed by tension-relieving suture, continuous vacuum sealing drainage was performed, and continuous even infusion and lavage were added 24 hours later. The thorax was fixed with an armor-like chest strap, the patients were guided to breathe abdominally, with both upper limbs fixed to the lateral chest wall using a surgical restraint strap. The bacterial culture results of wound exudation specimens on admission were recorded. The wound condition observed during operation, debridement method, muscle flap covering method, intraoperative bleeding volume, days of postoperative infusion and lavage, lavage solution volume and changes on each day, and postoperative complications and wound healing time were recorded. After discharge, the wound healing quality, thorax shape, and mobility functions of thorax and both upper limbs were evaluated during follow-up. The stability and closure of sternum were observed by computed tomography (CT) reexamination. Results: On admission, among 36 patients, 33 cases were positive and 3 cases were negative in bacterial culture results of wound exudation specimens. Intraoperative observation showed that 26 patients had no retrosternal mediastinal infection but had fresh granulation tissue in unhealed sternal wounds, palliative debridement was performed and bilateral pectoralis major muscles were advanced and abutted to cover the defect. In 10 patients with suspected retrosternal mediastinal abscess cavity, the local sternum was completely removed by bite and the defect was covered using flipped unilateral pectoralis major muscle. During the operation, one patient experienced an innominate vein rupture and bleeding of approximately 3 000 mL during mediastinal exploration, and the remaining patients experienced bleeding of 100-1 000 mL. Postoperative infusion and lavage were performed for 4-7 days, with a lavage solution volume of 3 500-4 500 mL/d. The lavage solution gradually changed from dark red to light red and finally clear. Except for 1 patient who had suture rupture caused by lifting the patient under the armpit during nursing on the 3rd day after surgery, the wounds of the other patients healed smoothly after surgery, and the wound healing time of all patients was 7-21 days. Follow-up for 3 to 9 months after discharge showed that the patient who had suture rupture caused by armpit lifting died due to multiple organ failure. In 1 patient, the armor-like chest strap was removed 2 weeks after surgery, and the shoulder joint movement was not restricted, resulting in local rupture of the suture, which healed after dressing change. The wounds of the remaining patients healed well, and they resumed their daily life. The local skin of patient's pectoralis major muscle defect was slightly sunken and lower than that of the contralateral thorax in the patients undergoing treatment of pectoralis major muscle inversion, while no obvious thoracic deformity was observed in patients undergoing treatment with pectoralis major muscle propulsion and abutment. The chest and upper limb movement in all patients were slightly limited or normal. CT reexamination results of 10 patients showed that the sternum was stable, the local sternum was closed or covered completely with no lacuna or defects. Conclusions: Once the wound associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy is formed, individualized and precise debridement should be performed as soon as possible, different transfer ways of pectoralis major muscle flap should be chosen to cover the defect, and postoperative continuous infusion and lavage together with strict thorax and shoulder joint restraint and immobilization should be performed. This treatment strategy can ensure good wound healing without affecting the shape and function of the donor area.

[Research advances on the role of Schwann cells in diabetic peripheral neuropathy]

Diabetic peripheral neuropathy (DPN) is one of the common chronic complications of diabetes, resulting in neuropathy of spinal nerve, cranial nerve, and vegetative nerve. Diabetic distal symmetric multiple neuropathy is the most representative lesion of DPN, including symptoms of bilateral limbs pain, numbness, and paresthesia, etc. DPN is one of the main reasons causing diabetic foot ulcer (DFU). Schwann cells (SCs) are the primary glia cells of the peripheral nervous system, which play very important role in repairing after nerve injury. As the target cells of chronic hyperglycemia, SCs' functions, including the formation of myelin sheath, the secretion of neurotrophic factors, energy supplying for the axon, and the guidance of axon regeneration, etc., are damaged under the action of high glucose. The destroyed functions of SCs can inhibit the repair of damaged nerves and accelerate the progress of DPN. Therefore, if the damage of high glucose to SCs can be effectively reduced, it will provide a new way for the treatment of DPN and DFU and reduce the morbidity of DFU. This review focuses on the function of SCs and its relationship with DPN.

[Investigation of a carbon monoxide poisoning accident with a hidden source]

In June 2022, a carbon monoxide poisoning accident with hidden source occurred in a bonded gold/silver wire manufacturing enterprise in Guangzhou, causing 10 people to be poisoned, of which 1 was caused by carbon monoxide poisoning and 9 by carbon monoxide contact reaction. The symptoms were dizziness, fatigue and vomiting. After 5 to 7 h, the saturation of carboxyhemoglobin in finger pulse was 4% to 10%, and the saturation of carboxyhemoglobin in blood gas biochemical analysis was 1.9% to 5.8%. The concentration of carbon monoxide detected in the carbon borne purification plant of the enterprise was 34.46-37.26 mg/m(3). It was judged that the accident was carbon monoxide poisoning caused by carbon monoxide gas being transported to the work post along the gas transmission pipeline due to abnormal operation of the carbon borne purification plant. By investigating the source and cause of poison, this paper provides a warning for the similar process to prevent similar events, and provides a new idea for the identification of chemical poisoning risk. At the same time, it is warned that similar enterprises should fully consider the risk of poisoning under specific circumstances, strengthen equipment maintenance and repair, and prevent the occurrence of similar incidents.

[Clinical effects of autologous split-thickness skin grafting for prefabricating urethra combined with scrotal flap in repairing middle urethral defect with penile defect]

Objective: To investigate the clinical effects of autologous split-thickness skin grafting for prefabricating urethra combined with scrotal flap in repairing middle urethral defect with penile defect. Methods: The retrospective observational study was conducted. Eight male patients (aged 14 to 58 years) with middle urethral defect and penile defect caused by various injuries who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University from January 2015 to January 2022. The length of urethral defect was 3 to 5 cm, and the wound area of penile defect after debridement was 5.0 cm×2.5 cm to 7.0 cm×5.5 cm. All the patients underwent autologous split-thickness skin grafting for prefabricating defect urethra in stage Ⅰ, and urethral anastomosis was performed and unilateral scrotal flap was transferred to reconstruct urethra and penis in stage Ⅱ. The area of scrotal flap was 6.0 cm×3.0 cm to 8.0 cm×6.0 cm. The wound in the donor area of skin graft was covered by oil gauze, and the wound of flap donor area was sutured directly. On the 7th day after the operation of stage Ⅱ, the survival of the flap was observed. In 3 weeks after the operation of stage Ⅱ, the urinary flow rate was measured by the urinary flow rate detector (urinary flow rate >15 mL/s was regarded as unobstructed urination), the urinary fistula and erectile function were observed, and the self-made therapeutic satisfaction questionnaire was used to investigate the therapeutic satisfaction degree of patients. During follow-up, the appearance of the flap recipient area was observed, the Vancouver scar scale (VSS) was used to evaluate the scar situation in the donor areas of skin graft and flap, the urinary flow rate was detected as before, the urethral stricture, urinary fistula, and erectile function were observed, and the therapeutic satisfaction degree of patients was investigated. Results: On the 7th day after the operation of stage Ⅱ, the flaps survived completely in 8 patients. In 3 weeks after the operation of stage Ⅱ, the urinary flow rate was 25.3 (18.0, 38.5) mL/s, with unobstructed urination, without urinary fistula and with erectile function, and the score of therapeutic satisfaction degree was 14.3 (14.0, 15.0). During follow-up of 1 to 7 years, the flap recipient area of 8 patients was full in appearance and not swollen, with similar color to the surrounding tissue; the VSS scores of the donor areas of skin graft and flap were 11.5 (10.0, 13.0) and 10.5 (9.3, 12.0), respectively, the urinary flow rate was 24.6 (17.7, 34.1) mL/s, with no urethral stricture, urinary fistula, and erectile dysfunction, and the score of therapeutic satisfaction degree was 13.5 (13.3, 14.8). Conclusions: Autologous split-thickness skin grafting for prefabricating urethra combined with scrotal flap in repairing the urethral and penile defects not only reconstructs the structure of urethra and the shape of penis, but also restores the sensation and erectile function of penis, with few postoperative complications, no obvious scar hyperplasia, and high satisfaction degree of patients, which is worthy of clinical promotion.

[Paradoxical worsening after treatment of choroidal tuberculoma: a case report]

A young woman who complained of visual acuity decreased in the right eye for 12 days visited the Department of Ophthalmology. A solitary and occupancy lesion was seen in the posterior pole of the fundus of the patient's right eye, accompanied by intracranial and pulmonary tuberculosis. The diagnosis was choroidal tuberculoma, intracranial tuberculoma, and invasive pulmonary tuberculosis. After anti-tuberculosis treatment, the lesions of lung were better, but the lesions in the right eye and brain were paradoxical worsening. Finally, the lesion was calcification and absorption after combined glucocorticoid therapy.

[Intravenous infusion of methylene blue to visualize the ureter in laparoscopic colorectal surgery]

Objective: Intraoperative localization of the ureter can contribute to accurate dissection and minimize ureteral injury in colorectal surgery. We aim to summarize a single center's experience of fluorescence ureteral visualization using methylene blue (MB) and explore its visualization efficiency. Methods: This is a descriptive case-series-study. Clinical data of patients who had undergone laparoscopic colorectal surgery and fluorescence visualization of the ureter in the Gastrointestinal Surgery Department of Guangdong Provincial People's Hospital from March 2022 to May 2022 were retrospectively collected. Patients with incomplete surgery videos, renal insufficiency, or allergic reactions were excluded. MB was infused with 0.9% NaCl at 1.0 mg/kg in 100 mL of normal saline for 5 to 15 minutes during laparoscopic exploration. Imaging was performed using a device developed in-house by OptoMedic (Guangdong, China) that operates at 660nm to achieve excitation of MB. Clinical information, MB dosage, rate of successful fluorescence, time to fluorescence, operation time, blood loss, intraoperative blood oxygen levels, pathological staging, changes in renal function, and post-operative complications were retrospectively analyzed. Results: The study cohort comprised 27 patients (24 men and 3 women) with an average age of (60.25±16.95) years and an average body mass index of (21.72±3.42) kg/m². The dosage of MB was 0.3-1.0 mg/kg and the infusion time was 5-15 minutes. Fluorescence signals were detected in all patients. The median time to signal detection was 20 (range, 10 to 40) minutes after MB infusion. The range of intraoperative blood oxygen fluctuation averaged 2.5% (range, 0 to 7.0%). The median change in creatine concentration was -1.3 (range, -17.2 to 29.2) µmol/L. No patients had complications associated with use of MB. Fluorescence visualization of the ureter was very valuable clinically in two patients (thick mesentery, stage T4). Conclusion: MB is a safe and effective means of visualizing the ureter by fluorescence during laparoscopic colorectal surgery, especially when the procedure is difficult. MB in a dosage of less than 1 mg/kg can slowly infused for more than 5 minutes during laparoscopic exploration. During the infusion, attention must be paid to blood oxygen fluctuations.

[A prospective randomized controlled study on the repair of skin and soft tissue defect in functional areas of children with full-thickness skin grafts from different sites of abdomen]

Objective: To compare and analyze the effect of repairing small skin and soft tissue defect wounds in functional areas of children with full-thickness skin grafts from different sites of abdomen. Methods: A prospective randomized controlled study was conducted. From January 2019 to June 2020, 60 female children with small skin and soft tissue defects in functional areas requiring full-thickness skin grafting, who met the inclusion criteria, were admitted to the First Affiliated Hospital of Air Force Medical University. According to the random number table, the children were divided into two groups, with 28 cases left in lateral abdomen group aged 5 (3, 8) years and 29 cases in lower abdomen group aged 5 (3, 7) years after the exclusion of several dropped-out children in follow-up. In lower abdomen group, 20 (12, 26) cm2 wounds of children were repaired with (24±10) cm2 full-thickness skin graft from transverse skin lines in the inferior abdomen area, while in lateral abdomen group, 23 (16, 32) cm2 wounds of children were repaired with (24±9) cm2 full-thickness skin graft from below the umbilical plane to above the groin in the lateral abdomen area. All the children were treated with continuous intradermal suture at the donor site incision and received continuous negative pressure treatment of -10.64 to -6.65 kPa in the donor and recipient areas after operation. The donor site was treated with a medical skin tension-reducing closure device since post-surgery day (PSD) 7. The use of medical skin tension-reducing closure device at the donor site, postoperative complications and suture removal time of the donor area were recorded, and the incidence of complications was calculated. On PSD 7, a self-designed efficacy satisfaction questionnaire was used to investigate the parents' satisfaction with the curative effect of their children. In post-surgery month (PSM) 1 and 6, Vancouver scar scale (VSS) was used to evaluate the scar at the donor site, and the VSS score difference between the two time points was calculated; the scar width at the donor site was measured with a ruler, and the scar width difference between the two time points was calculated. Data were statistically analyzed with independent sample t test or Cochran & Cox approximate t test, Mann-Whitney U test, and Fisher's exact probability test. Results: The proportion of children in lateral abdomen group who used the medical skin tension-reducing closure device in the donor area for equal to or more than 4 weeks after surgery was significantly higher than that in lower abdomen group (P<0.05). On PSD 7, there was one case of partial incision dehiscence in the donor area, one case of peripheral skin redness and swelling in the donor area, and one case of fat liquefaction in the donor area in lateral abdomen group, and one case of partial incision dehiscence in the donor area in lower abdomen group. The incidence of postoperative complications at the donor site of children in lower abdomen group was significantly lower than that in lateral abdomen group (P<0.05). Compared with that in lateral abdomen group, the suture removal time at the donor site of children after surgery in lower abdomen group was significantly shorter (t'=17.23, P<0.01). On PSD 7, the satisfaction score of parents with the curative effect of their children in lower abdomen group was significantly higher than that in lateral abdomen group (t'=20.14, P<0.01). In PSM 1 and 6, the VSS scores of scar at the donor site of children in lower abdomen group were 2.7±0.9 and 2.8±1.0, respectively, which were significantly lower than 7.1±2.2 and 9.1±2.7 in lateral abdomen group (with t values of 10.00 and 11.15, respectively, P<0.01). In PSM 6, the VSS score of scar at the donor site of children in lateral abdomen group was significantly higher than that in PSM 1 (t=3.10, P<0.01), while the VSS score of scar at the donor site of children in lower abdomen group was not significantly higher than that in PSM 1 (P>0.05). The VSS score difference of scar at the donor site of children in lateral abdomen group was significantly greater than that in lower abdomen group (Z=-8.12, P<0.01). In PSM 1 and 6, the scar widths at the donor site of children in lower abdomen group were 2.0 (1.0, 2.0) and 2.0 (2.0, 3.0) mm, respectively, which were significantly narrower than 6.0 (4.0, 10.0) and 8.5 (5.0, 12.0) mm in lateral abdomen group (with Z values of -13.41 and -14.70, respectively, P<0.01). In PSM 6, the scar width at the donor site of children in lateral abdomen group was significantly wider than that in PSM 1 (Z=-2.79, P<0.01), while the scar width at the donor site of children in lower abdomen group was not significantly wider than that in PSM 1 (P>0.05). The difference of scar width at the donor site of children in lateral abdomen group was significantly greater than that in lower abdomen group (Z=-14.93, P<0.01). Conclusions: The use of full-thickness skin grafts from the lower abdomen to repair small skin and soft tissue defect wounds in functional areas of children, especially girls, is effective, simple and easy to operate, and conforms to the principle of aesthetic repair. Compared with transplantation with full-thickness skin graft from the lateral abdomen, lower abdominal full-thickness skin grafting has a low incidence of donor site complications and no obvious scar hyperplasia, which is worthy of clinical promotion.

[Immune-related genes and their determined immune cell microenvironment to predict the prognosis of gastric adenocarcinoma]

Objective: Through bioinformatics analysis to screen key immune-related genes (IRGs) and cancer-related pathways in gastric adenocarcinoma (GAC) therapy, combining immune cell microenvironment to predict the prognosis of GAC. Methods: RNA sequencing and clinical data were obtained from public databases. Differentially expressed IRGs between GAC and normal tissues were identified by integrated bioinformatics analysis. Univariate and multivariate Cox regression analyses were applied to screen survival-associated IRGs. Then, we established the risk signature model and found another database for external validation. In addition, we explored the relationship with the immune cell microenvironment in each GAC sample using CIBERSORT algorithms. Results: A total of 78 differentially expressed IRGs were screened, including 47 up-regulated and 31 down-regulated genes. Subsequently, a five-IRGs signature (BMP8A、MMP12、NRG4、S100A9 and TUBB3) was significantly associated with the overall survival of GAC patients. Survival analysis indicated that patients in the high-risk group have a poor prognosis. The results of the multivariate analysis revealed that the risk score was an independent prognostic factor. Further analysis showed that the prognostic model had excellent predictive performance in both TCGA and GEO validated cohorts. Besides, the results of tumor-infiltrating immune cell analysis indicated that the risk score could reflect the status of the tumor immune microenvironment. Conclusion: BMP8A, MMP12, NRG4, S100A9 and TUBB3 with the risk signature model are associated with prognosis in patients with GAC, combined with tumor-infiltrating immune cells to provide new markers for immunotherapy in GAC.

[Epidemiological characteristics of local outbreak of COVID-19 caused by SARS-CoV-2 Delta variant in Liwan district, Guangzhou]

Objective: To analyze the epidemiological characteristics of a local outbreak of COVID-19 caused by SARS-CoV-2 B.1.617.2(Delta) variant in Liwan district, Guangzhou, and provide evidence for the further prevention and control of the Delta variant of COVID-19. Methods: From May 21 to June 18, 2021, the incidence data of COVID-19 caused by Delta variant were obtained from National Notifiable Disease Report System of Chinese Disease Prevention and Control Information System and Liwan District Center for Disease Control and Prevention of Guangzhou.Frequency analysis (proportions), histograms, and percentage stacked area plots were used to describe the epidemiological characteristics of the outbreaks. The incubation period and time-varying reproduction numbers (R_t) estimations were used for the further analysis. Results: By June 18, 2021, a total of 127 COVID-19 cases caused by Delta variant was reported in Liwan district. The youngest case was aged 2 years and the oldest was aged 85 years. There were 18.9% (24/127) aged <18 years, 43.3% (55/127) aged 18-59 years, and 37.8% (48/127) aged ≥60 years, the male to female ratio of the cases was 1∶1.35 (54∶73). The cases were mainly retired people (32.3%, 41/127), the jobless or unemployed (18.1%, 23/127), and students (16.5%, 21/127). The infections mainly occurred in Baihedong (70.1%, 89/127) and Zhongnan street (23.6%, 30/127) communities in the southern area of Liwan district. The median incubation period of the Delta variant infection was 6 days (range: 1-15 days). The clinical classification were mainly common type (64.6%, 82/127). The basic reproduction number (R₀) was 5.1, R_t which once increased to 7.3. The transmissions mainly occurred in confined spaces, such as home (26.8%), restaurant (29.1%), neighborhood (3.9%), and market (3.1%), the household clustering was predominant. Close contacts tracing (66.1%) and community screening (33.1%) were the main ways to find the infections. Conclusion: The COVID-19 outbreak caused by Delta variant in Liwan district of Guangzhou was highly contagious, with the obvious characteristics of household clustering and high proportions of cases in adults aged 18-59 years and elderly people aged ≥60 years.

[Analysis of occupational health status of radiation workers in Guangdong Province]

Objective: To discuss the effect of low-dose ionizing radiation on the health of radiation workers, and provide a basis for occupational health risk assessment of radiation workers. Methods: In January 2020, 3165 radiation workers who performed radiation occupational health examinations in Guangzhou Prevention and Treatment Hospital for Occupational Disease from January 2017 to December 2019 were selected as the research objects, and compared and analyzed the health status of radiation workers with different examination types (pre-job, in-job and off-job) , types of work, gender, and length of service. Results: The off-job occupational radiological health examination was rare at 2.3% (74/3165) . The abnormal detection rate of chest radiographs, renal function, thyroid function, and blood routine of the radiation workers in-job group was higher than that of the pre-job group (P<0.05) . No statistical difference was found in the abnormal detection rate of the examination items during the in-job group and the off-job group (P>0.05) . The blood routine abnormality detection rate of medical application group and industrial application group were higher than those of nuclear fuel group (P<0.05) . The abnormal detection rate of blood pressure and renal function of male radiation workers was higher than that of females, while the abnormal detection rate of blood routine of females was higher than that of males (P<0.05) . The abnormal detection rate of electrocardiogram, chest radiograph, blood pressure, renal function, thyroid function, and blood routine of radiation workers increased with increasing working age (P<0.05) . Conclusion: Occupational health status of radiation workers is not optimistic. Radiation occupational health monitoring should be strengthened, special attention should be paid to off-job radiation occupational health examination, focusing on the sensitive indicators of sensitive personnel, improving radiation protection conditions, and effectively protecting the occupational health of radiation workers.

[Polymorphism and Forensic Application of 11 Y-SNP in Guizhou Shui Ethnic Group]

Abstract

Objective To investigate the frequency distribution features of 11 Y-SNP of Guizhou Shui ethnic group, explore its genetic relationship with other ethnic groups and evaluate its forensic application value. Methods Multiplex amplification of the 11 Y-SNP of samples of 180 unrelated male individuals from Guizhou Shui ethnic group was performed with microsequencing technique. The frequency of haplogroup was calculated by direct counting method, and principal component analysis （PCA） of Guizhou Shui ethnic group and reference ethnic groups was performed by using Multi-variate statistical package （MVSP）. The F_st genetic distance between Guizhou Shui ethnic group and other ethnic groups was calculated with Arlequin v3.5. The phylogenetic tree was established with MEGA 4.0 software according to the F_st value. Results Six types of Y chromosome haplogroups were observed in total. Among which, the distribution frequency of O-M175 haplogroup was the highest （71.11%）, followed by C-M130 （25.00%）, and D-M174 （3.89%）. O1b-M268 （31.11%） and O2a2-IMS-JST021354 （28.33%） had a relatively high distribution frequency in O haplogroup. The paternal relationship between Guizhou Shui ethnic group and Guizhou Gelao ethnic group in the same language group was the closest. Conclusion The distribution of Y-SNP haplogroup of the Shui ethnic group in Guizhou has certain specificity, which can provide basic data for forensic biogeographic inference.

[Short-term effect of sodium zirconium cyclosilicate on potassium lowering in chronic kidney disease patients with hyperkalemia]

Objective: To investigate the efficacy of sodium zirconium cyclosilicate on emergency correction of hyperkalemia in chronic kidney disease patients. Methods: Patients with chronic kidney disease who were admitted to the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University from May to June 2020 were selected. Those who had hyperkalemia and took sodium zirconium cyclosilicate powder were finally included. The patient's clinical data and laboratory results were collected. Results: A total of 24 results were included from 21 patients. The age of patients was (48.9±13.5) years old. Fourteen patients were male, and 7 patients were female. After 2 hours of administration, the venous potassium level decreased from (5.85±0.52) mmol/L to (5.15±0.43) mmol/L (P<0.001, n=21), with an average decline of (0.71±0.43) mmol/L. Meanwhile, the arterial potassium level decreased from (5.50±0.40) mmol/L to (4.88±0.33) mmol/L (P<0.001, n=10), with an average decline of (0.62±0.29) mmol/L. Based on the initial venous potassium level, the patients were further divided into three groups. The average potassium decrease in<5.5 mmol/L group (4 patients), 5.5-<6.0 mmol/L group (11 patients) and ≥6.0 mmol/L group (6 patients) was (0.46±0.26) mmol/L, (0.62±0.38) mmol/L and (1.04±0.45) mmol/L, respectively. There was statistically significant difference of potassium reduction among the three groups (P=0.045). Moreover, the extent of potassium reduction was positively correlated with baseline venous potassium level (r=0.603, P=0.004, n=21). The study did not reveal any treatment-related adverse event. Conclusion: Sodium zirconium cyclosilicate powder can rapidly and effectively reduce the serum potassium level in chronic kidney disease patients with hyperkalemia.

[Effects of pedicled anterolateral thigh flaps in repairing skin and soft tissue defects in perineal region caused by necrotizing fasciitis]

Objective: To explore the effects of pedicled anterolateral thigh flaps in repairing skin and soft tissue defects in perineal region caused by necrotizing fasciitis. Methods: From March 2014 to December 2018, 6 patients with skin and soft tissue defects in perineal region caused by necrotizing fasciitis were admitted to Department of Burns of Hanzhong Central Hospital (hereinafter referred to as our hospital). Two female patients had labia major defects and 4 male patients had scrotum defects, with age of 43-68 years. The areas of skin and soft tissue defects after debridement were 4%-8% total body surface area. The wounds in non-joint and non-functional area were repaired with free split-thickness skin grafts from medial femoral region, and the residual wounds areas in perineal region after repair were 10 cm×4 cm-22 cm×10 cm, which were repaired with pedicled anterolateral thigh flaps, with area of 12 cm×5 cm-24 cm×12 cm. The secondary wounds in the donor sites were sutured directly or repaired with free split-thickness skin grafts from medial thigh on the same or opposite side of the wounds. The bacterial culture result of wound exudate, drug sensitivity test result, and blood bacterial culture result on admission were recorded. The postoperative flap survival was observed. The length of hospital stay, debridement times, and antibiotics use time were recorded. The flap swelling condition was observed to evaluate whether flap thinning operation was necessary, the sensory recovery of the flap and hip joint activity were evaluated, and the scrotum function of male patients was evaluated by urologist in our hospital during follow-up. Results: The bacterial culture results of wound exudate in 5 patients on admission showed Escherichia coli with 4 of them having the same bacteria and the other one having methicillin-resistant Staphylococcus aureus detected in their blood samples. All the flaps survived in 6 patients after the operation, with total length of hospital stay of (22±5) d, debridement of 3-5 times, and antibiotics use time of (13±3) d. During follow-up of 3 to 6 months after the operation, the flaps were slightly bloated in 2 patients, and the flap thinning operation was performed 6 months after wound repair. The sensory function recovered to normal in 2 flaps of patients with anterolateral femoral cutaneous nerve, and the superficial sensory function in the other flaps of patients recovered in different degrees.The hip joint activity was close to normal in all the patients, and the scrotum function was normal in 4 male patients. Conclusions: The pedicled anterolateral thigh flap showed good effects in repairing skin and soft tissue defects on perineal region caused by necrotizing fasciitis, with good appearance and function after operation, and the method is simple, safe, and easy to apply.

[Clinical application effect of blood circulation enhancement technique in repairing large area of skin and soft tissue defects of extremities with super large free anterolateral thigh flap]

Objective: To observe the clinical application effect of blood circulation enhancement technique in repairing large area of skin and soft tissue defects of extremities with super large free anterolateral thigh flap. Methods: From March 2014 to March 2017, 6 patients with large area of skin and soft tissue defects of extremities were hospitalized in our unit, including 5 males and 1 female, aged 27-65 years, 1 case of electric injury, 2 cases of coal burn, 3 cases of traffic injury, 2 cases involving upper limb, and 4 cases involving lower limb. After debridement, the wound area ranged from 26 cm×8 cm to 36 cm×15 cm, and the bone exposure area ranged from 24 cm×7 cm to 35 cm×14 cm. The blood circulation enhancement technique was used when the wound with bone exposure was repaired with super large free anterolateral thigh flap. The area of flaps ranged from 28 cm×10 cm to 38 cm×16 cm. The donor site of flap and the primary wound without bone exposure were repaired with medial thigh split-thickness skin graft of the donor leg of flap. The blood circulation enhancement technique mode during operation and the survival of flaps after operation were recorded, and the recovery of donor and recipient areas and the occurrence of complications were followed up. Results: Three patients were treated with simple vascular supercharging technique during flap transplantation, and the other 3 patients were treated with vascular supercharging and turbocharging technique during flap transplantation. All the flaps survived well in 6 patients without vascular crisis. Follow-up for 3 to 12 months after surgery showed that the blood flow of the flaps was good and the depth and superficial sensation recovered to varying degrees. Except for 1 case of upper limb flap, the other flaps had no obvious swelling and needed no second thinning. There were only depressed scars in the donor sites, and no obvious scar hyperplasia in the area without bone exposure repaired by the skin grafts. No short-term or long-term complications were found. Conclusions: The application of blood circulation enhancement technique in repairing large area of skin and soft tissue defects of extremities with super large free anterolateral thigh flaps provides reliable blood supply for the flaps and results in good effect after operation, which is worth popularizing.

[Prevalence of cataract among the population aged 50 years and over at different altitudes in Gansu Province]

Objective: To assess the prevalence and influence factors of cataract at different altitudes in Gansu Province. Methods: A total of 7 560 permanent residents aged 50 years and over in seven regions of Gansu Province (altitude, 900 meters to 3 500 meters) were selected as subjects, including 2 402 males and 5 158 females, with an average age of 62.04 years. The cluster random sampling method was used to conduct the survey at village or township health service centers. The investigation procedure included questionnaire survey, pre-investigation, visual acuity examination, intraocular pressure measurement, slit lamp microscopy and fundus examination. The diagnostic criterion for cataract was typical opacity of the lens or no other eye diseases that led to visual impairment but with visual acuity less than 0.7. The prevalence of cataract was calculated according to factors such as altitude, age and sex. The Chi-square test and two-element unconditional logistic regression were used for statistical analyses. Results: A total of 7 560 people were surveyed. The prevalence rate of cataract was 39.7%, and the age-standardized prevalence was 37.7%. The prevalence of cataract increased with age (χ(2)=2 107.19, P<0.01). It was 14.1% in the group of 50-59 years, 42.9% in the group of 60-69 years and 79.2% in the group of over 70 years. The prevalence of cataract also increased with altitude (χ(2)=33.66, P<0.01). It was 36.9% in the group of altitude less than 1 000 meters, 39.0% in the group of altitude between 1 000 meters and 1 999 meters, 45.9% in the group of altitude between 2 000 meters and 2 999 meters, and 51.5% in the group of altitude more than 3 000 meters. With age stratification, the prevalence of cataract at high altitude was higher than that at low altitude (χ(2)=26.74, 16.06, P<0.01). Multivariate regression analysis showed that the risk of cataract was higher in subjects at altitude of 2 000-2 999 meters than those below 1 000 meters (OR=1.42, 95%CI 1.11-1.82), and even higher in those at altitude of 3 000 meters (OR=1.76, 95%CI 1.01-3.06). Conclusions: High altitude and old age are important risk factors for cataract, and high altitude is an independent risk factor for cataract. It is necessary for local health institutions to take measures to reduce the prevalence of blindness and low vision, especially the blindness caused by cataract. (Chin J Ophthalmol, 2019, 55:589-594).

[Relationship between occupational stress, psychological capital and depressive symptoms among female workers in five electronic manufacturing enterprises]

Objective: To explore the relationship between occupational stress, psychological capital and depressive symptoms among electronic manufacturing female workers in the Pearl River Delta region. Methods: Using cluster sampling method, 845 female workers from 5 electronic manufacturing enterprises in the Pearl River Delta region were selected as research subjects from June to August 2017. The Effort Reward Imbalance questionnaire (ERI) , Psychological Capital questionnaire-24 (PCQ-24) and Patient Health questionnaire-9 (PHQ-9) were applied to measure the level of occupational stress, psychological capital and depressive symptoms in female workers. Results: Effort (r=0.197, P<0.01) and over commitment (r=-0.260, P<0.01) were positively correlated with the score of depressive symptoms, and the rewards was negatively correlated with depressive symptoms (r=-0.211, P<0.01) . The reward and over-commitment for depressive symptoms were accounted for 8.2%. Psychological capital was negatively correlated with depressive symptoms, and plays a partly mediating role in the relationship between occupational stress and depressive symptoms of female workers. The psychological capital for depressive symptoms was accounted for 8.7%. Conclusion: Occupational stress can affects the depressive symptoms of electronic manufacturing female workers, or indirectly affect depressive symptoms through psychological capital, reduce occupational stress and improve psychological capital as a way to relieve the depressive symptoms of female workers.

[HEAD-US-C quantitative ultrasound assessment scale in evaluation of joint damage in patients with moderate or severe hemophilia A received on-demand versus prophylaxis replacement therapy]

目的

探讨血友病关节超声评估量表（Haemophilic Early Arthropathy Detection with UltraSound in China，HEAD-US-C）对中间型/重型血友病A患者按需、预防治疗关节损伤评估的适用性。

方法

回顾性分析2015年6月至2017年7月70例接受肘、膝、踝关节超声检查的中间型及重型血友病A患者，应用HEAD-US-C超声评估量表及血友病关节健康评分量表2.1版（HJHS2.1）进行关节状况评分。对按需、预防治疗患者HEAD-US-C、HJHS评分进行相关性分析。

结果

70例中间型及重型血友病A患者共接受919例次关节超声检查。在中间型血友病患者中，按需、预防治疗组患者中位年靶关节出血次数差异无统计学意义[1（0，7）对1（0，5），z=1.271，P=0.137]。按需治疗组中位HEAD-US-C评分[1（0，6）对0.5（0，3），z=0.177，P=0.046]及HJHS评分[2（0，4）对2（0，3），z=0.375，P=0.007]明显高于预防治疗组。重型血友病患者按需、预防治疗组中位HEAD-US-C评分分别为4（0，7）、1（0，6）（z=2.189，P=0.008），中位HJHS评分分别为4（1，6）、2（0，5）（z=3.646，P<0.001），年靶关节出血次数分别为3（0，8）、2（0，8）（z=0.780，P=0.037），按需治疗组均高于预防治疗组。按需、预防治疗组患者HEAD-US-C评分与HJHS评分均存在正相关关系（P值均<0.05）。重型患者按需、预防治疗组HEAD-US-C评分与HJHS评分的相关系数分别为0.739（95%CI 0.708~0.767）、0.865（95%CI 0.848~0.880），95%CI不重合（P<0.05），预防治疗组两评分系统间具有更强的相关性。

结论

中间型/重型血友病A患者预防治疗疗效明显优于按需治疗。HEAD-US-C超声评估量表可有效评估中间型/重型血友病A患者按需、预防治疗关节损伤状况，与HJHS系统一致性较好，可为临床疗效评估提供客观指标。

[Clinical application and optimization of HEAD-US quantitative ultrasound assessment scale for hemophilic arthropathy]

目的

评价HEAD-US评估量表在血友病性关节病临床应用的可行性，提出优化的超声评估量表HEAD-US-C。

方法

2015年7月至2017年8月期间，91例血友病患者接受1 035例次关节超声检查，分别采用Melchiorre、HEAD-US、HEAD-US-C量表进行评分，分析与血友病关节健康评分量表（HJHS）评分之间的相关性并比较上述量表评价血友病性关节病的敏感性。

结果

91例患者均为男性，中位年龄16（4~55）岁，血友病A 86例，血友病B 5例。1 035例次关节检查Melchiorre、HEAD-US、HEAD-US-C量表的评分[M（P₂₅, P₇₅）]分别为2（0,6）、1（0,5）、2（0,6），均与HJHS评分之间存在相关关系（相关系数分别为0.747、0.762、0.765，P值均<0.001）。Melchiorre、HEAD-US-C、HEAD-US评分量表的阳性率分别为63.0%（95%CI 59.7%~65.9%）、59.5%（95%CI 56.5%~62.4%）、56.6%（95%CI 53.6%~59.6%），差异有统计学意义（P<0.001）。336例次无症状关节（HJHS评分0分）Melchiorre、HEAD-US-C、HEAD-US评分量表的阳性率分别为25.0%（95%CI 20.6%~29.6%）、17.0%（95%CI12.6%~21.1%）、11.9%（95%CI 8.4%~15.7%）（P<0.001）。40例有关节出血症状的血友病患者（107例次）关节出血前、出血后超声评分差异有统计学意义（P<0.05）。HEAD-US-C与HEAD-US评分的变化幅度比较，差异有统计学意义（P<0.001）。

结论

与Melchiorre比较，HEAD-US、HEAD-US-C与HJHS之间具有相似的良好的相关性。HEAD-US-C评分量表较HEAD-US更为敏感，尤其适合亚临床状态血友病性关节病的评估。

[Clinical effects of perforating branch flaps of medial vastus muscle in repairing secondary wounds in donor sites of free anterolateral femoral perforator flaps]

Objective: To investigate the clinical effects of perforating branch flaps of medial vastus muscle in repairing secondary wounds in donor sites of free anterolateral femoral perforator flaps. Methods: From August 2014 to December 2016, 12 patients (8 males and 4 females, aged 35-72 years) with skin and soft tissue defects of extremities associated with tendon and bone exposure were treated in Hanzhong Central Hospital. The sizes of the primary wounds after debridement were 10 cm×8 cm-22 cm×14 cm, and the wounds were repaired with 12 cm×10 cm-24 cm×16 cm free anterolateral femoral perforator flaps. The anterolateral femoral donor sites, which were 8.0 cm×4.0 cm-14.0 cm×7.5 cm in the secondary wounds after skin extensional suture, were repaired with perforating branch flaps of medial vastus muscle in the size of 9.0 cm×5.0 cm-15.0 cm×8.5 cm. The medial femoral donor sites were sutured directly. Results: All the perforating branch flaps of medial vastus muscle and free anterolateral femoral perforator flaps survived in 12 patients. Following up for 6 to 12 months, the medial femoral perforator flaps had good local shape and texture. The flaps of 8 patients without cutaneous nerve transection were sensitive. The sensation of the flaps of the other 4 patients gradually recovered, and the functions of the ipsilateral knee joints were normal. Conclusions: The medial femoral perforator flap has a stable anatomy and abundant blood supply, which can be used to repair the secondary wound in the donor site of the free anterolateral femoral perforator flap conveniently. It is safe and easy to be popularized. Moreover, it has a good shape and function after operation.

Effect of mannose on the lung function of rats with acute pancreatitis

The present study aimed to investigate the mechanisms by which mannose protects the lung injury induced in rats with acute pancreatitis (AP). An AP combined with Acute Lung Injury (ALI) model was established. A total of 90 healthy adult male Sprague-Dawley rats (300±50g weight) were randomly divided into three groups: sham operation group (SO group), severe acute pancreatitis lung injury group (SAP group), and mannose intervention group (MT group). Subsequently, each group was divided into two subgroups based on the time passed from intervention, namely 6 and 12 h. Each subgroup comprised 15 rats. The ratio of wet/dry weight of the lung tissue exhibited no significant change at different time points in the SO group. This parameter was significantly increased in the SAP group compared with the SO group at each time point of the treatment (P less than 0.05) and it was significantly lower in the MT group than that in the AP group (P less than 0.05) and it was significantly increased in the AP group at each time (P less than 0.05) compared with the SO group. The levels of TNF-α in the lung tissue in the SO group exhibited no significant change at different time points, but they were significantly decreased in the MT group at each time point (P less than 0.05) compared with the SAP group. The mannose receptor (MR) mRNA and protein levels in the lung tissues exhibited no significant change at different time points. The mRNA and protein levels of MR in the SAP group were significantly decreased at each time point (P less than 0.05) compared with the SO group. The mRNA and protein levels of MR, in the lung tissue of the MT group were significantly increased at each time point compared with the SAP group (P less than 0.05). Mannose could reduce the injury caused to the lung tissue of rats with severe acute pancreatitis by up-regulation of the expression of MR mRNA and protein.

[Confirming Indicators of Qualitative Results by Chromatography-mass Spectrometry in Biological Samples]

Because of the exist of complex matrix, the confirming indicators of qualitative results for toxic substances in biological samples by chromatography-mass spectrometry are different from that in non-biological samples. Even in biological samples, the confirming indicators are different in various application areas. This paper reviews the similarities and differences of confirming indicators for the analyte in biological samples by chromatography-mass spectrometry in the field of forensic toxicological analysis and other application areas. These confirming indicators include retention time （RT）, relative retention time （RRT）, signal to noise （S/N）, characteristic ions, relative abundance of characteristic ions, parent ion-daughter ion pair and abundance ratio of ion pair, etc.

[Screening of Differential Expression Proteins in Rat Brain Tissues after DAI by iTRAQ-LC-MS/MS]

OBJECTIVES

To screen for the differential expression proteins in brain tissues of SD rat after diffuse axonal injury （DAI） by isobaric tag for relative and absolute quantification-liquid chromatograph-mass spectrometer/mass spectrometer （iTRAQ-LC-MS/MS）, and to explore potential biomarkers available for the diagnosis of DAI.

METHODS

Animal models of DAI were established with the Marmarou method as reference, and the subjects were divided into blank control group （n=4）, sham strike group （n=4） and fatal strike group （n=4）, respectively. The proteins in rat brain tissues were detected by iTRAQ-LC-MS/MS, and bioinformatics analysis and verification were performed on the results and screened for the differential expression proteins.

RESULTS

A total of 2 016 proteins were identified and quantified. The bioinformatics analysis revealed that the proteins had wide distribution and function, and participated in different biological processes. There were 16 proteins showed differential expression in fatal strike group, including one up-regulated expression protein and 15 down-regulated expression proteins. The results of iTRAQ-LC-MS/MS were confirmed by Western blotting method.

CONCLUSIONS

Multiple differential expression proteins in rat brain tissues after DAI can be screened by iTRAQ-LC-MS/MS. This not only indicates a research direction for exploring the pathogenesis of DAI, but also provides potential biomarkers available for the diagnosis of DAI.

[Changes of HbCO in the Blood of Rats with Different CO Concentration and Inhalation Time]

OBJECTIVES

To explore the change rules of behavioral characteristics, survival time and saturation of carboxyhemoglobin （HbCO） in different CO concentration to provide experimental basis for the cases of CO poisoning death in forensic practice.

METHODS

Total 160 SD rats were randomly divided into four groups. CO with the concentration of 1 250 mg/m³, 3 750 mg/m³, 6 250 mg/m³ were continuously and respectively replenished in a self-made toxicant exposure equipment until rats died from poisoning. In different CO concentration, the behavioral characteristics and survival time of poisoning rats were observed and recorded. The saturation of HbCO in heart blood was detected by spectrophotometric method. Organs such as brain, heart, lung and liver, and heart blood were obtained via autopsy and histopathological observation was performed.

RESULTS

The behavioral characteristics of CO poisoning rats were limp and slow response. There were a gradual decrease of survival time and an increase of HbCO saturation in rats with the increase of CO concentration. Three rats in CO concentration of 1 250 mg/m³ group showed lower saturations of HbCO than the lethal dose and this situation hasn't been found in other groups.

CONCLUSIONS

The animal model of CO poisoning established under different CO concentration has the advantages such as simplicity and good repeatability, which lays a foundation to the further study for CO and other inhaled toxic gas in the research of forensic sciences.

Expression and clinical significance of rhubarb on serum amylase and TNF-alpha of rat model of acute pancreatitis

The aim of this study was to evaluate the therapeutic effect of rhubarb extract on acute pancreatitis. Ninety-six healthy Sprague Dawley rats, weighing 301±5.12 g were randomly divided into 4 groups: sham surgery (group A), acute pancreatitis model (group B), acute pancreatitis with normal saline (group C), and acute pancreatitis model with rhubarb (group D). The levels of serum amylase (AMY) and TNF-α were measured at 1st, 6th, 12th and 24th hour after modeling, and the pancreatic tissue were used to observe the pathologic changes. Compared to the sham group, the serum AMY and serum tumor necrosis factor (TNF-α) levels were significantly increased in the other groups (p <0.05). Compared to the model group and the saline group, the serum AMY, serum TNF-α level and pathological changes of rats in the rhubarb group were significantly lower (p <0.05). The serum AMY and TNF-α levels increased in acute pancreatitis. The rhubarb reduced the serum AMY and TNF-α level in rats with acute pancreatitis and reduced the pathological changes of pancreas and other tissues.

STAT3 Induces Immunosuppression by Upregulating PD-1/PD-L1 in HNSCC

Head and neck cancer is one of the most prevalent cancers around the world. Head and neck squamous cell carcinoma (HNSCC) accounts for nearly 90% of head and neck cancer. In recent years, significant advances have been made in immunotherapy for HNSCC. Although some clinical trials targeting immune checkpoints have shown success, the molecular mechanism for regulation of programmed death 1 (PD-1) and its ligand (PD-L1) is partially understood. In an effort to explore the effect of activation of signal transducers and activators of transcriptions (STAT3) on PD-1/PD-L1, the expression and correlation between phosphorylation of STAT3 and PD-1/PD-L1 were determined with immunostaining of human and mouse HNSCC tissue sections. PD-1/PD-L1 overexpression was found to be significantly associated with p-STAT3 in human and mouse HNSCC. Targeting STAT3 by a small molecule effectively inhibited the expression of PD-L1 in the CAL27 cell line. Furthermore, we found that blockade of STAT3 signaling downregulated PD-1/PD-L1 in a Tgfbr1/Pten 2cKO HNSCC mouse model. These findings suggest that STAT3 signaling plays an important role in PD-1/PD-L1 regulation and the antitumor immune response of HNSCC.

[An investigation of ionizing radiation dose in a manufacturing enterprise of ion-absorbing type rare earth ore]

Objective: To investigate radioactive source term dose monitoring and estimation results in a manufacturing enterprise of ion-absorbing type rare earth ore and the possible ionizing radiation dose received by its workers. Methods: Ionizing radiation monitoring data of the posts in the control area and supervised area of workplace were collected, and the annual average effective dose directly estimated or estimated using formulas was evaluated and analyzed. Results: In the control area and supervised area of the workplace for this rare earth ore, α surface contamination activity had a maximum value of 0.35 Bq/cm² and a minimum value of 0.01 Bq/cm²; β radioactive surface contamination activity had a maximum value of 18.8 Bq/cm² and a minimum value of 0.22 Bq/cm². In 14 monitoring points in the workplace, the maximum value of the annual average effective dose of occupational exposure was 1.641 mSv/a, which did not exceed the authorized limit for workers (5 mSv/a) , but exceeded the authorized limit for general personnel (0.25 mSv/a) . The radionuclide specific activity of ionic mixed rare earth oxides was determined to be 0.9. Conclusion: The annual average effective dose of occupational exposure in this enterprise does not exceed the authorized limit for workers, but it exceeds the authorized limit for general personnel. We should pay attention to the focus of the radiation process, especially for public works radiation.

Clinical Significance and Roles in Angiogenesis of Circulating Microparticles in Oral Cancer

Our recent study established the increased circulating microparticles (MPs) and their procoagulant activity in oral squamous cell carcinoma (OSCC). In the present study, we further evaluated different phenotypes of circulating MPs in OSCC patients and explored their clinical significance and effects on angiogenesis (a critical event in tumor progression). To conduct the study, circulating MPs in 45 OSCC patients and 18 healthy volunteers were characterized and quantified by transmission electron microscopy and flow cytometry. Correlations between circulating MPs and clinicopathologic data, microvessel density, and proangiogenic factor levels in patients with OSCC were analyzed by immunohistochemistry and Spearman rank correlation test. Additionally, the in vitro studies were performed with use of human umbilical vein endothelial cells. Our results showed that the levels of circulating MPs as well as the subsets of platelet-derived, endothelium-derived, and pan-leukocyte MPs in stages III to IV OSCC were significantly higher than stages I to II and healthy subjects. Moreover, these increased circulating MPs were significantly correlated with tumor size, TNM stages, microvessel density, and expression levels of vascular endothelial growth factor (VEGF) and matrix metallopeptidase 9 (MMP9) in OSCC patients. The in vitro studies revealed that circulating MPs isolated from OSCC patients could be effectively taken up by human umbilical vein endothelial cells and could promote the proliferation, migration, invasion, and tube formation of recipient endothelial cells, accompanied by increased expression of proangiogenic factors. In summary, circulating MPs play important roles in angiogenesis and local tumor progression of OSCC. Our results shed new light on the progression of OSCC and might be helpful to explore novel treatment strategies targeting tumor angiogenesis.

Distinguish and control the multi-level resistive switching for ferroelectric layer and interface in a YMnO3/Nb:SrTiO3 device

A YMnO₃/Nb:SrTiO₃ (YMO/NSTO) ferroelectric device with a step was fabricated by pulsed laser deposition.

Molecular phylogeny of Colletotrichum (Sordariomycetes: Glomerellaceae) inferred from multiple gene sequences

The genus Colletotrichum contains many important plant pathogens mainly distributed in tropical areas. Previous studies that utilized morphology or single genes have failed to resolve the phylogenetic relationships among the species. In this study, sequences of β-tubulin, 28S ribosomal DNA, and ITS region from nine species were analyzed separately and combined to establish a fast method to infer the phylogeny of Colletotrichum using maximum parsimony, maximum likelihood, and Bayesian inference methods. The tree topologies inferred from the combined data set received higher bootstrap and posterior probability support than those inferred from the individual data sets. Obtained phylogenies highly supported C. capsici as the earliest diverging lineage followed by C. nymphaeae. The remaining seven species clustered into two distinct clades. Clade 1 consists of two monophyletic subclades: C. circinans, C. trichellum, and C. caudatum form one subclade and three accessions of C. dematium form another subclade. In Clade 2, C. incarnatum is in the basal-most clade. Three accessions of C. musae and C. caricae form a strongly supported clade indicating their close relationship. Spore shape analysis reveals an interesting evolutionary trend in the spore shape from acute- to obtuse-ended conidia and from curved to straight conidia in the sampled group of species. A quick and reliable way to infer the phylogeny of Colletotrichum based on combined DNA sequence data is presented in this paper.

Elevated Level of Circulating Platelet-derived Microparticles in Oral Cancer

Numerous studies have demonstrated that circulating microparticles (MPs) play important roles in a variety of diseases (e.g., atherosclerosis, hypertension, and diabetes), but the association between circulating MPs and oral squamous cell carcinoma (OSCC) remains largely unknown. In the present study, the circulating platelet-derived MPs (PMPs) in 63 patients with OSCC, 22 patients with infected keratocystic odontogenic tumor, and 31 healthy volunteers were characterized and quantified by flow cytometric analysis. The coagulation function of patients with OSCC was correspondingly evaluated. Meanwhile, the inflammation-related cytokines were detected in plasma by enzyme-linked immunosorbent assay and in tumor tissues by immunohistochemistry. Our results showed that the plasma level of circulating PMPs was significantly higher in OSCC patients compared with healthy volunteers and patients with infected keratocystic odontogenic tumor, and they showed positive correlation with the increased level of fibrinogen. Moreover, the coagulation time was significantly shorter after the MPs were added to the MP-free plasma. Most important, the levels of interleukin 6 and tumor necrosis factor α in plasma and tumor tissues were significantly increased in OSCC patients, which were closely correlated with the elevated level of circulating PMPs. In summary, this study suggests that the elevated level of circulating PMPs, showing close correlation with the secretion of inflammation-related factors, may contribute to the increased procoagulant activity in patients with OSCC.

Transcriptome network-based method to identify genes associated with unruptured intracranial aneurysms

Intracranial aneurysm is a balloon or sac-like dilatation of blood vessels inside the brain. Despite their importance, the biological mechanisms of intracranial aneurysms are not totally understood. We used public genome-wide gene expression profile data to identify potential genes that are involved in intracranial aneurysm in order to construct a regulation network. Some of the transcription factors and target genes that we identified in this network had been identified as related to intracranial aneurysm in previous studies. We found additional transcription factors and target genes that are apparently related to intracranial aneurysm with this method. The confirmation of previously identified genes and transcription factors supports the usefulness of this transcriptome network analysis for the identification of candidate genes involved in intracranial aneurysm.

An analysis of developments and challenges in nutrient management in china

During the past 50 years, China has successfully realized food self-sufficiency for its rapidly growing population. Currently, it feeds 22% of the global population with 9% of the global area of arable land. However, these achievements were made at high external resource use and environmental costs. The challenge facing China is to further increase food production while drastically decreasing the environmental costs of food production. Here we review the major developments in nutrient management in China over the last 50 years. We briefly analyze the current organizational structure of the "advisory system" in agriculture, the developments in nutrient management for crop production, and the developments in nutrient management in animal production. We then discuss the nutrient management challenges for the next decades, considering nutrient management in the whole chain of crop production-animal production-food processing-food consumption by households. We argue that more coherent national policies and institutional structures are required for research extension education to be able to address the immense challenges ahead. Key actions include nutrient management in the whole food chain concomitant with a shift in objectives from food security only to food security, resource use efficiency, and environmental sustainability; improved animal waste management based on coupled animal production and crop production systems; and much greater emphasis on technology transfer from science to practice through education, training, demonstration, and extension services.

Nitrogen and phosphorus use efficiencies and losses in the food chain in China at regional scales in 1980 and 2005

Crop and animal production in China has increased significantly during the last decades, but at the cost of large increases in nitrogen (N) and phosphorus (P) losses, which contribute to ecosystem degradation and human health effects. This information is largely based on scattered field experiments, surveys and national statistics. As a consequence, there is as yet no comprehensive understanding of the changes in N and P cycling and losses at regional and national scales. Here, we present the results of an integrated assessment of the N and P use efficiencies (NUE and PUE) and N and P losses in the chain of crop and animal production, food processing and retail, and food consumption at regional scale in 1980 and 2005, using a uniform approach and databases. Our results show that the N and P costs of food production-consumption almost doubled between 1980 and 2005, but with large regional variation. The NUE and PUE of crop production decreased dramatically, while NUE and PUE in animal production increased. Interestingly, NUE and PUE of the food processing sector decreased from about 75% to 50%. Intake of N and P per capita increased, but again with large regional variation. Losses of N and P from agriculture to atmosphere and water bodies increased in most regions, especially in the east and south of the country. Highest losses were estimated for the Beijing and Tianjin metropolitan regions (North China), Pearl River Delta (South China) and Yangzi River Delta (East China). In conclusion, the changes and regional variations in NUE and PUE in the food chain of China are large and complex. Changes occurred in the whole crop and animal production, food processing and consumption chain, and were largest in the most populous areas between 1980 and 2005.

Observation of lasing emission from carbon nanodots in organic solvents

Lasing is observed from carbon nanodots (C-dots) dispersed into a layer of poly(ethylene glycol) coated on the surface of optical fibers under 266 nm optical excitation. This is due to the enhancement of photoluminescence intensity via the esterification of carboxylic groups of the C-dots, and the formation of high-Q cylindrical microcavities to support second-type whispering gallery modes.

Upconversion luminescence properties of Er(3+)-Bi3+ codoped CaSnO3 nanocrystals with perovskite structure

New phosphor nanocrystals of ASnO3:Er3+ (A = Ca, Sr, and Ba) and CaSnO3:Er(3+)-Bi3+ were prepared by a hydrothermal method. Their structures were examined by X-ray diffraction and Raman spectroscopy. Upconversion luminescence properties of the Er3+ ions in these host materials were investigated upon excitation at 980 nm. Green emission bands of Er3+ around 528 and 545 nm were more favorable in CaSnO3 than in SrSnO3 and BaSnO3. This was interpreted in terms of a crystal structural distortion and configuration coordinate model. The investigation of the upconversion luminescence of Er(3+)-Bi3+codoped CaSnO3 nanocrystals indicates that Bi3+ ions could largely sensitize the emission of Er3+ ions which was attributed to the efficient energy transfer from Bi3+ to Er3+ ions and the modification of the local symmetry of Er3+ ions. The results show that the CaSnO3:Er(3+)-Bi3+ nanocrystals have potential application for fabricating visible upconversion devices.

Significant acidification in major Chinese croplands

Soil acidification is a major problem in soils of intensive Chinese agricultural systems. We used two nationwide surveys, paired comparisons in numerous individual sites, and several long-term monitoring-field data sets to evaluate changes in soil acidity. Soil pH declined significantly (P < 0.001) from the 1980s to the 2000s in the major Chinese crop-production areas. Processes related to nitrogen cycling released 20 to 221 kilomoles of hydrogen ion (H+) per hectare per year, and base cations uptake contributed a further 15 to 20 kilomoles of H+ per hectare per year to soil acidification in four widespread cropping systems. In comparison, acid deposition (0.4 to 2.0 kilomoles of H+ per hectare per year) made a small contribution to the acidification of agricultural soils across China.

Photoconductive properties of selenium nanowire photodetectors

Selenium nanowires with a diameter of about 70 nm and a growth direction along [001] were fabricated via a facile solution method. Photoconductive properties of Se wires were systematically characterized via photodetectors made of single Se nanowire. The photodetectors exhibited a high light on-off current ratio (Ilight/ Idark) of 450, and a fast light response speed of millisecond rise/fall time with excellent stability and reproducibility. It was also observed that the response time strongly depend on the intensity of the illumination light: the rise time and fall time for a typical photodetector is 0.68/1.85, 0.53/1.70, 0.54/1.65, 0.51/1.59, and 0.49/1.58 ms for light intensity of 0.18, 0.26, 0.43, 0.96, and 1.89 mW/cm2, respectively, and the relationship between the light intensity and the photocurrent can be fitted by using a simple power law. The diameters of the nanowire were found to have a significant influence on the response speed with smaller Se nanowires showing higher response speed. Finally, the mechanisms of photoconduction and factors affecting the performance of the photodetectors were elucidated.

Epithelioid hemangioendothelioma of the oral cavity

OBJECTIVE

To investigate the clinicopathological characteristics and biologic behaviour of epithelioid hemangioendothelioma in the oral cavity.

MATERIALS AND METHODS

The clinical features and pathological findings of nine cases with intraoral epithelioid hemangioendothelioma were reviewed, including immunohistochemistry study.

RESULTS

This series comprised seven males and two females aged 6-53 years (mean 28 years). The sites of the tumour included the tongue (n = 4), lip (n = 1), the gingiva and alveoli of the maxilla (n = 1), the gingiva and alveoli of the mandible (n = 1), buccal mucosa (n = 1), and the floor of the mouth (n = 1). A painless solitary mass was the most common presentation and was found in eight cases. On pathology, the tumour grew in short strands, cords or nests of polygonal to slightly spindled epithelioid cells in fibro-myxoid stroma, with formation of intracytoplasmic lumina. Tumour cells were immunoreactive to CD34, FVIIIRAg, and vimentin. Focal-positive cytokeration were observed in three cases. Immunoreactivity for S-100 protein, epithelial membrane antigen (EMA) and human herpesvirus (HHV)-8 was negative in all cases. Two cases recurred after surgical excision, but no patient developed local or distant metastasis.

CONCLUSIONS

Wide local excision with long-term follow-up seems to be the treatment of choice for intraoral epithelioid hemangioendothelioma because of their unpredictable biological behaviour and recurrence potential.

Effects of isomalto-oligosaccharides on broiler performance and intestinal microflora

Dose effects of dietary isomalto-oligosacchrides (IMO) on broiler growth performance and characteristics of the intestinal microflora were compared. Three hundred sixty male broilers were randomly allotted to five treatments, with eight replicate pens per treatment and nine chicks per pen. Chicks were fed either a basal diet (control) or the basal diet plus 0.3, 0.6, 0.9, or 1.2% IMO. All chicks had access to feed and water ad libitum during the 7-wk experiment. At the end of the experiment, eight chicks per treatment were randomly chosen to measure the thymus index. Additionally, six birds per treatment were randomly selected to determine viable bacterial counts of Lactobacillus, Escherichia coli, and total aerobes in the digestive tract. The digesta of all the killed birds were also used to measure short-chain fatty acid (SCFA) levels. The results indicate that IMO enhanced growth performance during the initial 3 wk, but no further effects were detected during the latter 4 wk of the experiment. Isobutyrate level in crop content and acetate level in duodenum digesta were decreased by supplementation with IMO (P < 0.05). Isovalerate level in duodenum digesta was decreased in the 0.3 and 0.6% IMO groups (P < 0.001), whereas the jejunum butyrate and isobutyrate levels of the 0.3% IMO group were higher than in other groups (P < 0.05). The facultative microflora of the crop and cecum were not affected by IMO supplementation. However, the thymus index was increased significantly in chicks consuming diets containing 0.3% IMO.

Nonlinear response and optical limiting in SrBi(2)Ta(2)O(9) thin films

SrBi(2)Ta(2)O(9) (SBT) thin films on quartz substrates were prepared by use of the pulsed-laser deposition technique. The nonlinear refractive indices, n(2) , of the SBT films were measured by use of z-scan techniques with picosecond pulses. Large negative nonlinear refractive indices of 3.84 and 3.58cm(2)/GW were obtained for the wavelengths 532 nm and 1.064mum , respectively. The two-photon absorption coefficient was determined to be 7.3 cm/GW for 532 nm. The limiting behavior of SBT thin film on a quartz substrate was investigated in an f/5 defocusing geometry by use of 38-ps-duration, 532-nm, 1.064mum laser excitation.

Reconstruction of intraoral defects after cancer surgery using cervical pedicle flaps

PURPOSE

This article reports the results of using cervical myocutaneous flaps for reconstruction of small- and medium-sized oral defects.

PATIENTS AND METHODS

One hundred thirty-one cervical pedicle flaps were used for reconstruction of the defects after resection of oral cancer. Primary sites of the lesions were the tongue, buccal mucosa, floor of the mouth, and lower gingiva.

RESULTS

Infrahyoid myocutaneous flaps were used in 53 cases, sternocleidomastoid flaps in 47 cases, and platysma flaps in 31 cases. Among the 131 patients, there was complete necrosis of the skin paddle in 5 cases and partial necrosis in 7 cases. The success rate was 92.5%, 89.4%, and 90.3%, respectively for the 3 types of flaps.

CONCLUSIONS

It was concluded that cervical pedicle flaps have clinical value in selected patients needing reconstruction of small- and medium-sized defects after intraoral cancer surgery.

Lyme borreliosis in rhesus macaques: effects of corticosteroids on spirochetal load and isotype switching of anti-borrelia burgdorferi antibody

Experimental Borrelia burgdorferi infection of rhesus monkeys is an excellent model of Lyme disease and closely parallels the infection in humans. Little is known about the interaction of host immunity with the spirochete in patients with chronic infection. We hypothesized that rapid development of anti-B. burgdorferi antibody in immunocompetent nonhuman primates (NHPs) is the major determinant of the reduction of the spirochetal load in Lyme borreliosis. This hypothesis was tested by measurement of the spirochetal load by PCR in association with characterization of the anti-B. burgdorferi humoral immune response in immunocompetent NHPs versus that in corticosteroid-treated NHPs. Although anti-B. burgdorferi immunoglobulin G (IgG) antibody was effectively inhibited in dexamethasone (Dex)-treated NHPs, anti-B. burgdorferi IgM antibody levels continued to rise after the first month and reached levels in excess of IgM levels in immunocompetent NHPs. This vigorous production of anti-B. burgdorferi IgM antibodies was also studied in vitro by measurement of antibody produced by B. burgdorferi-stimulated peripheral blood mononuclear cells. Despite these high IgM antispirochetal antibodies in Dex-treated NHPs, spirochetal loads were much higher in these animals. These data indicate that Dex treatment results in interference with isotype switching in this model and provide evidence that anti-B. burgdorferi IgG antibody is much more effective than IgM antibody in decreasing the spirochetal load in infected animals.