[Treatment methods of upper limbs with destructive electric burns and its clinical efficacy].

Objective: To investigate the treatment methods of upper limbs with destructive electric burns and its clinical efficacy. Methods: A retrospective observational study was conducted. From July 2014 to December 2020, 20 male patients with destructive electric burns in upper limbs who met the inclusion criteria were admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital, aged from 21 to 57 years, of whom 7 patients underwent emergency surgery, and a total of 20 affected limbs were treated with limb salvage. The necrotic bone was resected in 5 affected limbs, the residual hand and wrist at the distal end of left affected limb was replanted to the residual end of the right forearm in one patient in a cross heterotopic way, and short reduction and replantation after osteotomy were performed for two affected limbs with distal ulnar and radial necrosis. After thorough debridement, the area of wound proposed to be repaired by tissue flap was from 12 cm×7 cm to 58 cm×13 cm. According to the size and distribution of wound, the wounds of 2 affected limbs were repaired by transplantation of pedicled latissimus dorsi myocutaneous flap and free groin flap with vascular anastomosis. The wounds of the remaining 17 affected limbs were repaired with the transplantation of free latissimus dorsi myocutaneous flap, anterolateral thigh flaps, and paraumbilical perforator flap, with 10 affected limbs with larger wounds being jointly transplanted with the groin flap or the paraumbilical perforator flap on the other side. The total grafted tissue flap area was 20 cm×8 cm to 52 cm×20 cm. During tissue flap transplantation, according to the length of blood vessel defect in the affected limb, the distal artery of the affected limb was bridged with the distal part of flap vascular pedicle, undamaged vein on the affected side, superficial vein of abdominal wall, and great saphenous vein, etc., in 14 affected limbs, and the great saphenous vein was grafted in 3 of them with impeded distal return for recanalization of distal limb veins. The wound in the donor area was repaired by direct suture or grafting with split-thickness scalp. After the wound was basically healed, the functional rehabilitation training was started gradually, and the functional reconstruction and scar rectification surgery were started 3 months after tissue flap transplantation. The survival of tissue flaps/skin grafts, wound healing, limb salvage, and follow-up status after surgery were recorded. At the last follow-up, the function of the successfully salvaged limb was evaluated and scored by the disabilities of the arm, shoulder and hand (DASH) scoring scale. Results: After surgery, the grafted tissue flap in the affected limb and the skin grafts transplanted on the wound at flap donor site survived, and wounds at the recipient and donor sites healed well. Two affected limbs had distal necrosis within 10 days after tissue flap transplantation, and the middle and upper forearms were amputated. The remaining 18 affected limbs were successfully salvaged (including shortened replantation and cross heterotopic replantation). During 6-48 months of follow-up, 5 affected limbs that were successfully salvaged developed aseptic dissolution of residual tendon and bone tissue 3 to 18 months after tissue flap transplantation, which gradually healed after surgical debridement combined with vacuum sealing drainage treatment. At the last follow-up, the stump of two affected limbs healed well after amputation; 18 affected limbs that were successfully salvaged all survived well, of which 8 affected limbs had good recovery of finger flexion and extension function and thumb opponensplasty and could complete daily activities independently, 9 affected limbs regained partial mobility and could complete daily activities such as dressing and eating with the assistance of the opposite upper limb or auxiliary devices, and one affected limb had no function. At the last follow-up, the functional scores of DASH scoring scale of the 18 affected limbs that were successfully salvaged ranged from 30.0 to 100. Conclusions: Timely surgical debridement, proper treatment of the injured bone tissue, effective vascular bridging for reconstruction of the distal artery of the affected limb, and the use of blood-rich tissue flap to repair the wound, combined with early rehabilitation and functional restoration treatment, are beneficial to salvage the upper limb with destructive electric burns and improve the function of the affected limb.

[Clinical effects of expanded flaps in reconstructing scar contracture deformities in the face and neck after extensive burns].

Objective: To investigate the clinical effects of expanded flaps in reconstructing scar contracture deformities in the face and neck after extensive burns. Methods: A retrospective observational study was conducted. From May 2016 to September 2022, 17 patients with scar contracture deformities in the face and neck after extensive burns were admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital, including 13 males and 4 females, aged 23 to 55 years, with 3 patients having degree Ⅱ cervical contracture, 14 patients having degree Ⅲ cervical contracture, and 12 patients having facial scar contracture deformity. In the first stage, 34 rectangular skin and soft tissue expanders (hereinafter referred to as expanders) with rated capacity of 100-600 mL were inserted into the face, chest, shoulder, and abdomen, and then the normal saline was injected for expansion. In the second stage, the scar tissue was removed and the contracture was released to correct the deformity. Two expanded facial flaps were transplanted in local fashion, 17 expanded flaps were transplanted in pedicled fashion, and 15 expanded flaps were freely transplanted to repair the secondary wounds after release, with artery pressurization was performed in 7 flaps. Indocyanine green fluorescence imaging was used to evaluate the arterial blood perfusion and venous return of the flaps during transplantation. The incision area of 32 flaps except 2 facial flaps was 10 cm×8 cm-36 cm×16 cm. The wounds of 31 flap donor sites were closed by direct suture, and the wound of 1 flap donor site was repaired by autologous split-thickness scalp transplantation. The skin condition of inserted place, expansion time, and total amount of normal saline injection of expanders, complications of skin and soft tissue expansion surgery, and survival of flap after the second stage surgery were observed and recorded. The long-term face and neck reconstruction effect and recovery of flap donor area were followed up. At the last follow-up, the 5-level Likert scale was used to evaluate the efficacy satisfaction of patients. Results: Of the 34 expander inserted places in 17 patients, 22 places were superficial scar skin after deep partial-thickness burns, 8 places were superficial scar skin after multiple skin donations, and 4 places were normal skin. After 4 to 15 months of expansion, the total normal saline injection volume was 238 to 2 000 mL, with no complications occurred. After the second stage surgery, the distal part of 2 pedicled flaps was partially necrotic, and the necrotic wounds were healed after flap dressing and free transplantation of contralateral expanded triangular flaps, respectively; the other flaps survived completely. During 6 to 18 months of follow-up, except for 2 expanded paraumbilical flaps and 1 expanded groin flap, which were bloated and improved by flap thinning, the appearance and texture of the other flaps were good, and all the flap donor sites recovered well. At the last follow-up, the face and neck scar contracture deformities were significantly improved in all patients, and the satisfaction of curative effect of patient was very satisfactory in 8 patients and relatively satisfactory in 9 patients. Conclusions: The expanded flaps of chest, abdomen, and other parts, combined with local advance, pedicled, and free transplantation, can effectively reconstruct scar contracture deformities in the face and neck after extensive burns, restore the function of operative area and improve the appearance simultaneously, with high degree of patient satisfaction, which is worthy of promotion in clinic.

[Effects of miniature free groin perforator flaps in repairing small wounds on hands].

Objective: To investigate the effects of miniature free groin perforator flaps in repairing small wounds on hands. Methods: The retrospective observational study was conducted. Fifteen patients with 16 small wounds on hands were admitted to Tongren Hospital of Wuhan University & Wuhan Third Hospital from July 2020 to October 2022, including 12 males and 3 females, aged 19 to 56 years. The size of skin and soft tissue defect was 2.0 cm×1.5 cm to 6.0 cm×3.0 cm after debridement. According to size and shape of the wounds, 13 single-lobe perforator flaps and 2 bilobed perforator flaps were designed in the groin region, with the flap size of 4.5 cm×2.5 cm to 7.5 cm×3.5 cm. According to the condition of the recipient area, the arteries and veins at the pedicle of the flap were anastomosed to the arteries and veins of the recipient area respectively. The wounds in the donor area of the flap was closed by layered and tension-reducing suture. The thickness of the flap was measured during operation. The survival of the flap was observed, and the complications in the donor and recipient areas were recorded after operation. The appearance and texture of the flap were observed during follow-up. At the last follow-up, the sensory recovery of the affected hand was evaluated, the function of the affected hand was evaluated according to the trial standard of the upper limb partial function evaluation of the Hand Surgery Society of the Chinese Medical Association, the scar in the donor and recipient areas were observed, and the satisfaction of patients for the curative effects was inquired. Results: The thickness of the flap was ranged from 0.3 to 1.0 cm, with an average thickness of 0.6 cm. After operation, 11 single-lobe flaps and 2 bilobed flaps survived well; in the left 2 single-lobe flaps, one flap had venous crisis but returned to normal after removing stitches to reduce tension and bloodletting of flaps, while the other one flap had a little necrosis on tip but healed after dressing change. No complications occurred in donor and recipient areas. During follow-up of 8 to 35 months after operation, the flaps had good elasticity and soft texture; 8 flaps were slightly bloated and were trimmed 3 to 8 months after operation, while the appearances of the other flaps were good. At the last follow-up, all flaps recovered protective feeling; the function of the affected hand was evaluated as excellent in 10 cases, good in 4 cases, and fair in 1 case; only linear scar remained in the donor and recipient areas; the patients were satisfied with the appearance and function recovery of the affected hand. Conclusions: The miniature free groin perforator flaps in repairing small wounds on hands have the advantages of high survival rate of flaps, hidden flap donor area, little damage, few complications, good repair effect, etc., showing clinical application value. It is recommended for repairing non-functional wounds on hands.

[Value of glycosylated hemoglobin A1c and apolipoprotein A-1 ratio on predicting outcome of patients with acute coronary syndrome].

Objective: To investigate the predictive value of glycosylated hemoglobin A1c/apolipoprotein A-1 (HbA1c/ApoA-1) ratio for major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS). Methods: The present study is a retrospective cohort study. ACS patients who were hospitalized and underwent coronary angiography at Beijing Hospital from March 2017 to March 2019 were enrolled. Baseline information such as sex, age, previous history, Gensini score, HbA1c and ApoA-1 were analyzed. Patients were divided into two groups according to presence or absence of MACEs and the difference on HbA1c/ApoA-1 ratio was compared between the two groups. According to the tertiles of HbA1c/ApoA-1 levels, patients were divided into high (5.87-16.12), medium (4.50-5.83) and low (2.11-4.48) HbA1c/ApoA-1 groups. Cox proportional risk model was used to evaluate the differences in MACEs and all-cause mortality among the three groups. Kaplan-Meier survival analysis was used to compare the differences of MACEs between the various HbA1c/ApoA-1 groups. Results: A total of 366 ACS patients were included in this study. The mean age of the patients was (65.9±10.3) years. There were 59 MACEs and 10 all-cause deaths during the mean of (22.3±4.4) months follow-up. After adjusting for age, systolic blood pressure, history of diabetes and Gensini score, the incidence of MACEs was 2.45 times higher in the high HbA1c/ApoA-1 group than in the low HbA1c/ApoA-1 group (95%CI 1.16-5.18, P=0.019). There was no significant difference in all-cause mortality between the high and low HbA1c/ApoA-1 groups (P=1.000). Kaplan-Meier survival analysis showed that patients in the high HbA1c/ApoA-1 group had the highest risk of MACEs, while patients in the low HbA1c/ApoA-1 group had the lowest risk of MACEs (P<0.01). Spearman rank correlation analysis showed that HbA1/ApoA-1 ratio was positively correlated with Gensini score in ACS patients (r=0.274, P<0.01). Conclusion: High HbA1c/ApoA-1 ratio was an independent risk factor for MACEs in ACS patients. Patients with high HbA1c/ApoA-1 ratio had more severe coronary artery disease lesions. HbA1c/ApoA-1 ratio may be used as a potential risk stratification biomarker for ACS patients, it might be useful for the early identification of high-risk population and for predicting the incidence of MACEs among ACS patients.

[Changes in the related indicators of bone formation and bone resorption in severely burned rats].

Objective: To observe the changes in the related indicators of bone formation and bone resorption in severely burned rats. Methods: The experimental research method was adopted. Thirty female Sprague-Dawley rats aged 6 to 8 weeks were divided into sham injury group, 12% total body surface area (TBSA) full-thickness burn group, and 24%TBSA full-thickness burn group according to the random number table, with 10 rats in each group. The rats were treated on the back correspondingly, after which, the burned rats were rehydrated by intraperitoneal injection according to the Parkland formula, and the wound was coated with 20 g/L iodophor until wound healing. On post injury day (PID) 28, the tibia tissue of rats in each group was collected. The new bone tissue and the number of osteoclasts were observed after staining with Masson and tartrate-resistant acid phosphatase, respectively. The abdominal aortic blood of rats in each group was harvested for serum preparation. The bone metabolism indexes of serum calcium ion and phosphorus ion concentration were determined by the methyl thymol blue colorimetric method and phosphomolybdic acid method, respectively. The serum levels of bone formation marker of aminoterminal propeptide of type 1 procollagen (P1NP) and bone resorption marker of beta-carboxy-terminated peptide of type Ⅰ collagen (ß-CTX) were determined by enzyme-linked immunosorbent assay. The first lumbar spine tissue of rats in each group was collected, and the mRNA expression levels of osteoprotegerin, receptor activator of nuclear factor-κB ligand (RANKL), tumor necrosis factor receptor-associated factor 6 (TRAF-6), nuclear factor of activated T cell 1 (NFATC1), c-Fos, and c-Src were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction. Data were statistically analyzed with one-way analysis of variance, Bonferroni method, Welch test, Games-Howell test, Kruskal-Wallis test, Mann-Whitney U test, and Bonferroni correction. Results: On PID 28, compared with that in sham injury group, the formation of new bone tissue in the tibia tissue of rats in the two burn groups was decreased, and the larger the burn area, the more obvious the decrease. The numbers of osteoclasts in the tibia tissue of rats in the two burn groups were similar, both significantly more than the number in sham injury group. On PID 28, the serum calcium ion concentration and serum level of ß-CTX of rats in the three groups were similar (P>0.05). The serum phosphorus ion concentration of rats in 24%TBSA full-thickness burn group was significantly higher than that in 12%TBSA full-thickness burn group (P<0.05), and the serum phosphorus ion concentrations in the two burn groups were significantly higher than the concentration in sham injury group (P<0.01). The serum level of P1NP of rats in 24%TBSA full-thickness burn group was significantly lower than that in sham injury group (P<0.01). On PID 28, the mRNA expression levels of osteoprotegerin in the first lumbar spine tissue of rats in sham injury group, 12%TBSA full-thickness burn group, and 24%TBSA full-thickness burn group were 1.01±0.20, 1.71±0.83, and 2.24±0.51, respectively, and that in 24%TBSA full-thickness burn group was significantly higher than that in sham injury group (P<0.01). The mRNA expression level of RANKL in the first lumbar spine tissue of rats in 24%TBSA full-thickness burn group was 1.31±0.17, which was significantly higher than 1.00±0.14 in sham injury group and 0.97±0.10 in 12%TBSA full-thickness burn group (P<0.01). The mRNA expression levels of TRAF-6, NFATC1 (Z=3.141, 3.782), and c-Src in the first lumbar tissue of rats in 12%TBSA full-thickness burn group and 24%TBSA full-thickness burn group and the mRNA expression level of c-Fos in the first lumbar tissue of rats in 12%TBSA full-thickness burn group were significantly higher than those in sham injury group (P<0.05 or P<0.01). The mRNA expression levels of c-Fos and c-Src in the first lumbar spine tissue of rats in 12%TBSA full-thickness burn group were significantly higher than those in 24%TBSA full-thickness burn group (P<0.01). Conclusions: Severe burns can cause a decrease in the generation of new bone tissue, an increase in the number of osteoclasts and the serum phosphorus ion concentration, and a decrease in the serum level of P1NP in rats. The level of osteoprotegerin, RANKL, TRAF-6, NFATC1, c-Fos, and c-Src in bone tissue showed an increasing trend while the level of NFATC1, c-Fos, and c-Src showed a decreasing trend with the increase of burn area.

[Plasm trimethylamine-N-oxide level and association with lesion severity in coronary heart disease patients with type 2 diabetes mellitus].

Objective: To investigate the association between trimethylamine-N-oxide (TMAO) and the degree of coronary atherosclerosis in coronary heart diseases (CHD) patients with type 2 diabetes mellitus. Methods: Consecutive patients, who underwent coronary angiography due to suspected CHD in Beijing Hospital from November 2016 to January 2018, were screened in this cross-sectional study. According to blood glucose level, previous medical history and coronary angiography results, they were divided into CHD without type2 diabetes mellitus(CHD-nDM) group and CHD with type2 diabetes mellitus(CHD-DM) group. Plasma TMAO levels in each group were measured by LC-MS/MS. Spearman correlation analysis was used to evaluate the correlation between TMAO and the number of diseased vessels and Gensini scores. Multivariate logistic regression was used to analyze the correlation between TMAO and high Gensini scores. Results: A total of 590 patients were enrolled in the study, including 238 patients in CHD-DM group and 352 patients in CHD-nDM group. Patients were older, body mass index, blood pressure level, prevalence of history of hypertension and statins use were higher in CHD-DM group than in CHD-nDM group (all P<0.05). The proportion of patients with multivessel disease (2 or more vessels) was also higher in CHD-DM group than in CHD-nDM group (P<0.001). Gensini score was higher in CHD-DM group than in CHD-nDM group (P<0.05). Fasting blood glucose, glycosylated hemoglobin and urea were significantly higher, while low-density lipoprotein cholesterol and hemoglobin were significantly lower in CHD-DM group than in CHD-nDM group (all P<0.05). The levels of TMAO was significantly higher in CHD-DM group than in CHD-nDM group (P<0.001). Spearman correlation analysis showed that TMAO was positively correlated with the number of diseased vessels, Gensini score, age and blood glucose level (r=0.178, 0.189, 0.260, 0.111, respectively, all P<0.01). Multivariate logistic regression analysis showed that, TMAO level was still positively correlated with high Gensini score in CHD-DM group (OR=2.25, 95%CI 1.16-4.38, P=0.017), but not in CHD-nDM group (OR=1.29, 95%CI 0.72-2.31, P=0.386) after adjusting for age, sex, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol, triglyceride, history of hypertension, hyperlipidemia, smoking and statin use. Conclusions: In CHD patients with tupe 2 diabetes mellitus, the plasma TMAO level is significantly increased and is independent and positively correlated with the degree of coronary artery disease.

[Analysis of the clinical features and the risk factors of severe adenovirus pneumonia in children].

Objective: To analyze the clinical characteristics, risk factors for critical illness and death of severe adenovirus pneumonia in children, so as to provide clinical evidences for early diagnosis and reliable treatment. Methods: A total of 75 pediatric cases with severe adenovirus pneumonia admitted to Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from January to October 2019 were studied. The clinical features, laboratory and imaging data, therapeutic approaches, efficacy of the treatments and prognosis were investigated retrospectively. Patients were divided into severe group and critical group. Chi square test and Mann-Whitney U rank sum test were used to analyze the data of the two groups. The risk factors for critical illness and death were analyzed by univariate and multivariate Logistic regression. Results: Among the 75 children, there were 52 males and 23 females, aged from 3 months to 8 years, including 30 of severe cases and 45 of critical case. The positive rate of adenovirus antigen in nasopharyngeal swab was 21% (15/72), and the positive rate of serum adenovirus IgM antibody was only 13% (10/75). However, the positive rate of adenovirus nucleic acid in nasopharyngeal swab was 75% (21/28). What is more, the positive rates of metagenomics next generation sequencing (mNGS) in plasma and bronchoalveolar lavage fluid were 92% (33/36) and 96% (54/56), respectively, of which 95% (63/66) were confirmed as adenovirus type 7. Relatively high dose of ribavirin and integrated therapeutic approaches (respiratory support, glucocorticoids, immunoglobulin and organ supportive therapies) were used. The recovery rate was 77% (58/75), the improvement rate was 8% (6/75) and the mortality rate was 15% (11/75). The proportion of children with the duration of fever longer than 3 days after ribavirin treatment in the critical group was significantly higher than that in the severe group(51% (18/35) vs. 8% (2/26), χ2=12.949, P<0.05). The risk factors for critical illness were younger than 4 years, longer duration of fever before and after admission to PICU, oxygenation index<300 mmHg (1 mm Hg=0.133 kPa), ferritin>1 000 µg/L, lactate dehydrogenase (LDH)>1 500 U/L, 5 lung lobes involvement, pleural effusion and (or) air leakage (all P<0.05). Among them, 5 lung lobes involvement was the independent risk factor for critical illness (adjusted OR=49.641, 95%CI 4.186-588.618, P=0.002). Risk factors for death included longer duration of fever after being admitted to PICU, oxygenation index<100 mmHg, ferritin>2 000 µg/L, interleukin (IL)-6>100 ng/L, LDH>1 500 U/L, pleural effusion and (or) air leakage (all P<0.05). Among them, IL-6>100 ng/L was the independent risk factor for the mortalities of critically ill children (adjusted OR=16.094, 95%CI 2.059-25.787, P=0.008). Conclusions: The mortality rate of severe pediatric adenovirus pneumonia caused by adenovirus type 7 is high. High positive rates of adenovirus nucleic acid in nasopharyngeal swabs and mNGS in plasma or bronchoalveolar lavage fluid contribute to early diagnosis, and mNGS can also be used for serotyping. Younger children under 4 years of age, persistent fever, extensive pulmonary lesions and significantly increased inflammatory cytokines such as IL-6 are warning indicators for critical illness and poor prognosis. Relatively high dose of ribavirin combined with integrated therapeutic approaches are beneficial for prognosis.

Detecting causal relationship between metabolic traits and osteoporosis using multivariable Mendelian randomization.

By adopting the extension approaches of Mendelian randomization, we successfully detected and prioritized the potential causal risk factors for BMD traits, which might provide us novel insights for treatment and intervention into bone-related complex traits and diseases. INTRODUCTION: Osteoporosis (OP) is a common metabolic skeletal disease characterized by reduced bone mineral density (BMD). The identified SNPs for BMD can only explain approximately 10% of the variability, and very few causal factors have been identified so far. METHODS: The Mendelian randomization (MR) approach enables us to assess the potential causal effect of a risk factor on the outcome by using genetic IVs. By using extension methods of MR-multivariable MR (mvMR) and MR based on Bayesian model averaging (MR-BMA)-we intend to estimate the causal relationship between fifteen metabolic risk factors for BMD and try to prioritize the most potential causal risk factors for BMD. RESULTS: Our analysis identified three risk factors T2D, FG, and HCadjBMI for FN BMD; four risk factors FI, T2D, HCadjBMI, and WCadjBMI for FA BMD; and three risk factors FI, T2D, and HDL cholesterol for LS BMD, and all risk factors were causally associated with heel BMD except for triglycerides and WCadjBMI. Consistent with the mvMR results, MR-BMA confirmed those risk factors as top risk factors for each BMD trait individually. CONCLUSIONS: By combining MR approaches, we identified the potential causal risk factors for FN, FA, LS, and heel BMD individually and we also prioritized and ranked the potential causal risk factors for BMD, which might provide us novel insights for treatment and intervention into bone-related complex traits and diseases.

[Effects of acute paraquat poisoning on cognitive ability in humans].

Objective: To explore the effects of acute paraquat poisoning on cognitive function of patients through neuropsychologic test. Methods: In June 2019, 36 patients with acute paraquat poisoning in the emergency department of a provincial hospital in Hebei Province were selected as the case group. 36 healthy individuals were selected as control group. The cognitive function and depressive state were assessed by mini mental state scale, auditory word learning test, digit span test, connection test, Boston Naming Test and geriatric depression scale. Results: The results of Mini-Mental State examination showed that the total score of the case group was lower than that of the control group, the difference was statistically significant (P<0.05) . The results of the Auditory Vocabulary Learning test showed that the scores of delayed recall, clue recall, corrective ability and semantic learning strategies of the case group were significantly lower than those in the control group (P<0.05) . There was no significant difference in the scores of immediate memory between the two groups (P>0.05) . The scores of Digit Span test and Boston Naming test in the control group were higher than those in the case group, the Trail Making test time in the control group was shorter than that in the case group, and the differences were statistically significant (P<0.05) . Conclusion: Acute paraquat poisoning can impair human cognitive ability to a certain extent.

[Preliminary analysis on COVID-19 case spectrum and spread intensity in different provinces in China except Hubei province].

Objective: To analyze the characteristics of COVID-19 case spectrum and spread intensity in different provinces in China except Hubei province. Methods: The daily incidence data and case information of COVID-19 were collected from the official websites of provincial and municipal health commissions. The morbidity rate, severity rate, case-fatality rate, and spread ratio of COVID-19 were calculated. Results: As of 20 March, 2020, a total of 12 941 cases of COVID-19 had been conformed, including 116 deaths, and the average morbidity rate, severity rate and case-fatality rate were 0.97/100 000, 13.5% and 0.90%, respectively. The morbidity rates in Zhejiang (2.12/100 000), Jiangxi (2.01/100 000) and Beijing (1.93/100 000) ranked top three. The characteristics of COVID-19 case spectrum varied from province to province. The first three provinces (autonomous region, municipality) with high severity rates were Tianjin (45.6%), Xinjiang (35.5%) and Heilongjiang (29.5%). The case-fatality rate was highest in Xinjiang (3.95%), followed by Hainan (3.57%) and Heilongjiang (2.70%). The average spread ratio was 0.98 and the spread intensity varied from province to province. Tibet had the lowest spread ratio (0), followed by Qinghai (0.20) and Guangdong (0.23). Conclusion: The intervention measures were effective in preventing the spread of COVID-19 and improved treatment effect in China. However, there were significant differences among different regions in severity, case-fatality rate and spread ratio.

Committee machines-a universal method to deal with non-idealities in memristor-based neural networks.

Artificial neural networks are notoriously power- and time-consuming when implemented on conventional von Neumann computing systems. Consequently, recent years have seen an emergence of research in machine learning hardware that strives to bring memory and computing closer together. A popular approach is to realise artificial neural networks in hardware by implementing their synaptic weights using memristive devices. However, various device- and system-level non-idealities usually prevent these physical implementations from achieving high inference accuracy. We suggest applying a well-known concept in computer science-committee machines-in the context of memristor-based neural networks. Using simulations and experimental data from three different types of memristive devices, we show that committee machines employing ensemble averaging can successfully increase inference accuracy in physically implemented neural networks that suffer from faulty devices, device-to-device variability, random telegraph noise and line resistance. Importantly, we demonstrate that the accuracy can be improved even without increasing the total number of memristors.

Short-term Effects of Cadmium and Mercury on Soil Nematode Communities in a Pot Experiment.

Analysis of soil nematode feeding groups and functional guilds were used as a valuable tool to detect heavy metal pollution. Effects of cadmium (Cd) at 5 mg/kg, mercury (Hg) at 20mg/kg, combined Cd and Hg at 5+20mg/kg on the nematode communities were studied after three months application. Nematodes were collected from soil in rhizosphere of Morning glories (Pharhiris nil) which were applied as heavy metal accumulators and were grown in the experimental pots. Both single and combined heavy metals had marked effects on the nematode abundance, life-history strategies and feeding type composition. Bacteriovores and c-p 2 group were found to be the most abundant trophic group and functional guild, respectively. Acrobeloides and Pratylenchus were the most two abundant genera, decreasing number of them was responsible for the significant difference between control and polluted treatments. Cd-5 and Cd-Hg 5+20 presented lower values of nematode diversity index (H') and evenness index (J') than Hg-20. The combination of Cd and Hg showed lower nematode trophic diversity (TD), in comparison with single Cd or Hg. Conversely, heavy metals addition exhibited no pronounced effect on Maturity index (MI), structural index (SI) and enrichment index (EI). Our results demonstrate that genera composition is a better indicator to short-term heavy metal effects than some common indicator indices and emphasize that deeper assemblage analyses are needed for a correct interpretation of short-term disturbance on soil nematodes.

[The preliminary analysis on the characteristics of the cluster for the COVID-19].

Since December 2019, COVID-19, a new emerging infection disease, has spread in 27 countries and regions. The clusters of many cases were reported with the epidemic progresses. We collected currently available information for 377 COVID-19 clusters (1 719 cases), excluded the hospital clusters and Hubei cases, during the period from January 1 to February 20, 2020. There were 297 family clusters (79%), case median was 4; 39 clusters of dining (10%), case median was 5; 23 clusters of shopping malls or supermarkets (6%), case median was 13; 12 clusters of work units (3%), case median was 6, and 6 clusters of transportation. We selected 325 cases to estimate the incubation period and its range was 1 to 20 days, median was 7 days, and mode was 4 days. The analysis of the epidemic situation in a department store in China indicated that there was a possibility of patients as the source of infection during the incubation period of the epidemic. From February 5 to 21, 2020, 634 persons were infected on the Diamond Princess Liner. All persons are susceptible to the 2019 coronavirus. Age, patients during the incubation period and the worse environment might be the cause of the cases rising. The progress of the two typical outbreaks clearly demonstrated the spread of the early cases in Wuhan. In conclusion, screening and isolating close contacts remained essential other than clinical treatment during the epidemic. Especially for the healthy people in the epidemic area, isolation was the key.

[Clinical application of lobulated transplantation of free anterolateral thigh perforator flap in the treatment of electric burns of limbs].

Objective: To explore the clinical efficacy of lobulated transplantation of free anterolateral thigh perforator flap in repairing electric burn wounds of limbs. Methods: From August 2014 to April 2019, 19 patients with electric burns in the limbs were hospitalized in our unit, including 18 males and 1 female, aged 20-58 years. There were 37 wounds deep to bone. The area of wounds ranged from 3.0 cm×2.0 cm to 40.0 cm×8.0 cm. Multiple-perforator-based anterolateral thigh flap was designed and resected. Then the flap was lobulated taking the respective perforators of the lateral circumflex femoral artery as the axial vessels before being transplanted to the debrided wounds in the limbs. The blood vessel trunk or the perforator vessels of flap lobes were anastomosed with the respective vessels in the recipient sites. The wounds were repaired with respective lobes of the flap when repairing multiple wounds in one surgical procedure, whereas the lobes were spliced or staggered to cover the wound to fit the shape of wound when repairing a single irregular wound in one surgical procedure. For the limb with distal blood supply disorder, the blood supply branch of flap was used to reconstruct the blood supply. If necessary, an appropriate length of vein was taken for transplantation. The improvement of reconstructed blood supply was observed. The number of surgeries, the number of anterolateral thigh perforator flaps, the number and size of flap lobes, the number of anastomosed vessels in each surgery, the treatment of the donor sites, the length of each surgery, the postoperative complications and survival condition of flap lobes were recorded. The upper extremity function was evaluated with the Carroll's Upper Extremity Function Test Scale, and the patients' satisfaction degree with the therapeutic effect of each surgery was investigated with a 5-point Likert Scale during follow-up. Surgeries were divided into single wound group of repairing one wound at one time and multiple wounds group of repairing two or more wounds at one time. The number of anastomosed vessels in each surgery, the treatment of the donor sites, the length of each surgery, and the postoperative survival condition of the flap lobes were compared between the two groups. Surgeries were divided into early group of performing surgery within post burn day 7 and late group of performing surgery on post burn day 7 and beyond. The postoperative complications and survival condition of flap lobes, the evaluation score of upper limb function and the patients' satisfaction degree with the therapeutic effect of each surgery at the last follow-up were compared between the two groups. Data were processed with independent sample t test, Mann-Whitney U test, or Fisher's exact probability test. Results: The blood supply of 5 patients with distal hand or finger blood supply disorder recovered or improved significantly after vascular transplantation. A total of 46 lobes [(2.2±0.4) lobes per flap] were obtained from 21 anterolateral thigh perforator flaps in 19 patients with 21 surgeries. The area of flap lobes ranged from 4.0 cm×3.0 cm to 24.0 cm×13.0 cm. In each surgery, 2.0 (1.5, 3.0) arteries and 3.0 (2.0, 3.0) veins were anastomosed. Six donor sites were repaired by thin split-thickness scalp, and 15 donor sites were closed directly. The duration of each surgery was (8.9±1.7) h. After surgery, bleeding and hematoma occurred in 2 flap lobes and local infection occurred in 5 flap lobes, which were improved after management. Vascular crisis occurred in 4 flap lobes, and exploratory surgeries were performed, after which 2 lobes survived, while the other 2 lobes necrotized and were repaired by other methods. The rest flap lobes survived well. After each postoperative follow-up of 3 to 60 months, the flap covering areas of the limbs were well-recovered. At the last follow-up, the function evaluation score of 20 affected upper limbs was 85 (63, 90) points, and the score of patients' satisfaction degree with the therapeutic effect of each surgery was (4.4±0.7) points. A total of 30 flap lobes were obtained in 14 surgeries and repaired 30 wounds respectively in multiple wounds group, and 16 flap lobes were obtained in 7 surgeries and were spliced to repair 7 large irregular wounds in single wound group. There were no statistically significant differences in the number of anastomosed artery or vein in each surgery, and the duration of each surgery between multiple wounds group and single wound group (Z=0.240, 0.081, t=0.180, P>0.05), and the condition of skin grafting in the donor sites and the postoperative survival of the flap lobes in multiple wounds group were similar to those in single wound group (P>0.05). A total of 22 flap lobes were obtained in 10 surgeries and repaired 18 wounds in early group, and 24 flap lobes were obtained in 11 surgeries and repaired 19 wounds in late group. The incidence of postoperative hematoma, infection, vascular crisis, and survival of flap lobes in early group were similar to those in late group (P>0.05). There were no statistically significant differences in the patients' satisfaction degree with the therapeutic effect of each surgery at the last follow-up between early group and late group (t=0.701, P>0.05). At the last follow-up, the function evaluation score of 9 upper limbs in early group was 90 (85, 97) points, significantly higher than 80 (40, 85) points of 11 upper limbs in late group (Z=2.431, P<0.05). Conclusions: Free lobulated anterolateral thigh perforator flap is suitable for simultaneous repair of multiple electric burn wounds of limbs, as well as the repair of a single large irregular wound. It has the clinical advantages of less damage to the donor site and good repair quality. The early flap transplantation is beneficial to improve the function of limbs with electric burns.

[Expanded flaps with vascular anastomosis for the treatment of scar contracture deformities of extensively burned patients].

Objective: To explore the effect of expanded flaps with vascular anastomosis in the treatment of scar contracture deformities of extensively burned patients. Methods: From April 2016 to February 2018, 9 patients with severe scar contracture deformities caused by extensive burns were hospitalized in our unit, including 7 males and 2 females, aged 23-54 years. There were 14 sites of scar contracture deformities and dysfunction, including 8 in face and neck, 2 in elbow, and 4 in wrist and hand. The expander was inserted into the chest or abdomen and was expanded by 2 to 3 times of its rated volume with injection of normal saline. After satisfied expansion, the expanded flap was harvested and transplanted with arteriovenous anastomosis onto the recipient site, where the scar was removed, the deformity was corrected, and the contracture was released. The number of expanders, the volume of normal saline injected, the period of expansion, the complications of skin and soft tissue expansion, the number, size, thickness, transplantation modes, and survival of flaps, and the repair method of donor site were observed and recorded. The reconstruction effect of scar contracture deformity was followed up. The patients' satisfaction with the therapeutic effect of various surgical sites during follow-up was investigated with a 5-point Likert Scale. The Burn Specific Health Scale-Brief was used to evaluate the quality of life of the patients pretreatment and during follow-up. Data were processed with paired sample t test or Wilcoxon signed-rank sum test. Results: A total of 16 expanders were inserted in this group of patients, including 6 in the chest and 10 in the abdomen. The volume of normal saline injected at the end of expansion was (1 421±348) mL. The expansion time was (8.1±2.6) months. One case of expander leakage and one case of injection port turnover resulted in failure of water injection occurred during expansion. Totally 17 flaps were resected from 16 expanded areas. The size of flaps ranged from 15 cm×13 cm to 30 cm×25 cm. The thickness was (0.49±0.06) cm in 6 chest flaps and (0.76±0.15) cm in 11 abdomen flaps. Free transplantation with vascular anastomosis was performed in 14 flaps, and pedicled transplantation supercharged with distal vascular anastomosis was performed in 3 flaps, one of which the vascular pedicle was divided and re-anastomosed to the other side of the recipient area 2 weeks later. Except for one donor site of abdomen flap which was transplanted with thin split-thickness scalp, the other donor sites were sutured directly. After operation, 2 flaps were slightly necrotic at the distal end and healed after dressing change and thin split-thickness scalp transplantation respectively, while the remaining 15 flaps all survived. During the follow-up of 6-24 months, the texture of the flaps was soft. The abdomen flap transplanted to the palm of hand in one patient was slightly hypertrophic, which was thinned 3 months after operation, while the other flaps were good in thickness. At the last follow-up, the appearance and function of the sites repaired by flaps of all patients were obviously improved compared with those before operation, the satisfaction score of the patients with the therapeutic effect of the surgical site was (4.4±0.6) points, the total score of quality of life and the scores of heat sensitivity, treatment antipathy, body image, and affect of patients were significantly higher than those before treatment (t=3.232, 2.683, 3.969, 2.884, 2.588, P<0.05), while the scores of hand function, sexuality, interpersonal relationship, simple function abilities, perception in returning to work of patients were close to those before treatment (t=0.778, 1.000, 1.664, Z=1.826, 1.633, P>0.05). Conclusions: Expanded flaps with vascular anastomosis are suitable for the treatment of scar contracture deformities of extensively burned patients. The flaps are large in size and suitable in thickness. The donor sites are easy to be closed directly. The treatment can obviously improve the appearance, function, and the quality of life of the patients, with a high satisfaction of patients.

[Clinical effects of free superficial femoral artery femoral triangle perforator flap in the repair of skin and soft tissue defects in extremities].

Objective: To investigate the clinical effects of free superficial femoral artery femoral triangle perforator flap in the repair of skin and soft tissue defects in extremities. Methods: From January 2016 to November 2017, 14 patients (9 males and 5 females, aged 19 to 54 years) with skin and soft tissue defects in extremities accompanied with tendon and bone exposure were admitted to our unit. The size of skin and soft tissue defects after debridement ranged from 7 cm×3 cm to 10 cm×7 cm. The defects were repaired with free superficial femoral artery femoral triangle perforator flaps, with size ranging from 13.0 cm×2.0 cm to 20.0 cm×4.5 cm. The medial femoral cutaneous nerve was applied to the flap. The perforator flap was grafted onto the medial femoral cutaneous nerve in 6 patients. The donor sites were sutured directly. The survival of flaps and the follow-up of patients were observed. Results: All flaps of 14 patients survived successfully. The recipient sites and donor sites were healed completely in 13 patients, and 1 patient with partial skin necrosis at the edge of flap was healed after treatment. All patients were followed up for 6 months to 1 year after the operation. The flaps were in good shape, with nearly normal color and soft texture and no cicatrix contracture deformity. The flaps recovered protective sense in 6 patients who had medial femoral cutaneous nerve grafting, and the sensory recovery of the flap was slightly worse in the remaining 8 patients. There was no significant complications on the appearance and walking of the donor thigh in 14 patients, only a linear scar was left on the inner thigh, and no numbness was felt in the donor sites of patients. Conclusions: The free superficial femoral artery femoral triangle perforator flap is an ideal therapy for repairing skin and soft tissue defects in extremities.

High power generation of THz from 1550-nm photoconductive emitters.

Two photoconductive emitters - one with a self-complementary square spiral antenna, and the other with a resonant slot antenna - were fabricated on a GaAs epilayer embedded with ErAs quantum dots. Driven with 1550 nm mode-locked lasers, ~117 µW broadband THz power was generated from the device with the spiral antenna, and ~1.2 µW from the device with resonant slot antenna. The optical-to-THz conversion is through extrinsic photoconductivity.

[Therapeutic efficacy of paclitaxel-coated balloon for de novo coronary lesions with diameters larger than 2.8 mm].

Objective: To evaluate the efficacy of paclitaxel-coated balloon for de novo coronary lesions with diameters ≥ 2.8 mm. Methods: This prospective study included 215 consecutive patients with 238 de novo lesions, who received paclitaxel-coated balloon angioplasty in Beijing Hospital from May 2014 to June 2016. According to the reference vessel diameter, the patients were divided into large vessel disease (LVD) group (reference vessel diameter≥2.8 mm, 85 patients and 90 lesions) and small vessel disease (SVD) group (reference vessel diameter<2.8 mm, 130 patients and 148 lesions). Clinical characteristics, interventional procedures and major adverse cardiovascular events (includingall-cause mortality, non-fatal myocardial infarction and target lesion revascularization) after procedure were compared between the 2 groups. Results: (1)Patients in LVD group were younger than SVD group ((60.1±11.1) years old vs. (65.0±10.6) years old, P<0.01), and less patients had diabetes (24.7% (21/85) vs. 43.1%(56/130), P<0.01).(2)Prevalence of three-vessel disease (35.5%(30/85) vs. 53.6%(67/130), P<0.05) and complex lesions (type B2/C,34.4% (31/90) vs. 50.0%(74/148), P<0.05) were significantly lower in LVD group than in SVD group.(3) During pre-dilation, the rate with plain balloons use was significantly higher in SVD group than in LVD group(76.4%(113/148) vs. 58.9%(53/90), P<0.01), while the proportion of additional use of non-compliant balloons was significantly higher in LVD groupthan in SVD group(20.0% (18/90) vs. 3.4% (5/148) , P<0.01). The ratio of paclitaxel-coated balloon diameter/RVD was significantly lower (0.87±0.12 vs. 0.96±0.15, P<0.01) and the duration of dilationwas significantly shorter ((41.5±9.5) seconds vs. (45.1±9.1) seconds, P<0.01) in LVD group than those in SVD group. Each group had 1 failure case that was bailout stented with drug-eluting stents. The success rate of paclitaxel-coated balloon treatment was similar in LVD group and SVD group (98.9% (89/90) vs. 99.3%(147/148), P>0.05).(4) At the fourth day of procedure, there was 1 acute myocardial infarction requiring emergent target lesion revascularization in SVD group. No major adverse cardiovascular event was observed in LVD group during hospitalization. Forty-two patients with 53 lesions, including 27 LVD lesions and 26 SVD lesions,underwent coronary angiography at (9.4±4.6) months after paclitaxel-coated balloon intervention. The quantitative coronary angiography analysis showed that minimal lumen diameter significantlyincreased during follow-up than that of post-procedurein SVD group ((1.71±0.36)mm vs. (1.52±0.30)mm, P<0.05) , while in LVD group the minimal lumen diameter was similar between during follow-up and post-procedure ((2.35±0.48)mm vs. (2.19±0.34)mm, P>0.05). Major adverse cardiovascular event rate was 0 in LVD group and 2.3%(3/130) in SVD group (P>0.05) during follow up. No death was observed in this patient cohort. Conclusion: Treatment with paclitaxel-coated balloon for de novo coronary lesions with diameters≥2.8 mm is safe and effective.