Cigarette smoke extract stimulates PCSK9 production in HepG2 cells via ROS/NF‑κB signaling

Cigarette smoke (CS) exposure is a risk factor for dyslipidemia and atherosclerosis. Reduced expression of low-density lipoprotein receptor (LDLR) in hepatocytes may be one of the underlying mechanisms for these disorders. The aim of the present study was to investigate the molecular mechanism underlying the regulatory effect of CS extract (CSE) on proprotein convertase subtilisin/kexin type 9 (PCSK9) and low LDLR expression in HepG2 cells. PCSK9 and LDLR mRNA and protein expression levels in HepG2 cells were evaluated after CSE treatment via reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. In addition, total intracellular reactive oxygen species (ROS) production was determined via 2,7-dichlorofluorescein diacetate fluorescence. CSE significantly increased PCSK9 expression and inhibited LDLR expression in a time- and concentration-dependent manner. Furthermore, CSE significantly induced ROS production and nuclear factor κB (NF-κB) activation. However, pretreatment with a ROS scavenger or an NF-κB inhibitor significantly attenuated the CSE-induced changes in PCSK9 and LDLR expression. In addition, pretreatment with melatonin markedly reduced ROS production, NF-κB activation and PCSK9 expression, and increased LDLR expression in the CSE-treated cells. These data suggest that melatonin inhibits CSE-regulated PCSK9 and LDLR production in HepG2 cells via ROS/NF-κB signaling.

An indirect comparison by Bayesian network meta-analysis of drug-coated devices versus saphenous vein graft bypass in femoropopliteal arterial occlusive disease

OBJECTIVE

To compare the efficacy and safety between drug-coated devices (DCDs) and bypass surgery with saphenous vein graft (BSV) in femoropopliteal arterial occlusive disease.

METHODS

A Bayesian network meta-analysis and indirect comparison were performed. Randomized controlled trials of BSV, bypass surgery with prosthetic graft, bare metal stents, endoluminal bypass (covered stent), percutaneous transluminal angioplasty, and DCDs treating femoropopliteal arterial occlusive disease were collected. The primary end point was target lesion revascularization/target vessel revascularization, and secondary end points were all-cause mortality, limb salvage, and early complications (PROSPERO registry number: CRD42019136530).

RESULTS

Forty-two trials and 6867 patients were included. The comparison of DCDs and BSV revealed no significant difference in the 1-year target lesion revascularization/target vessel revascularization (DCDs vs BSV: odds ratio [OR], 0.60; 95% credible interval [CrI], 0.16-2.39). Total early complications from BSV were significantly higher than those from DCDs (DCDs vs BSV: OR, 0.14; 95% CrI, 0.05-0.45), and the main complications of BSV were not death related. There was also no significant difference in systemic early complications (DCDs vs BSV: OR, 0.19; 95% CrI, 0.00-7.82) and 1-year amputation rate (DCDs vs BSV: OR, 2.81; 95% CrI, 0.16-89.53). The 30-day (DCDs vs BSV: OR, 0.38; 95% CrI, 0.00-110.46), 1-year (DCDs vs BSV: OR, 0.96; 95% CrI, 0.24-3.29), 2-year (DCDs vs BSV: OR, 1.60; 95% CrI, 0.64-4.95), and 5-year all-cause mortality rates (DCDs vs BSV: OR, 2.05; 95% CrI, 0.92-4.39) showed no significant differences between DCDs and BSV, although there was a noticeable tendency toward significant results of a higher 5-year mortality rate.

CONCLUSIONS

There is no significant difference between DCDs and BSV in short-term efficacy or short- and long-term mortality. Despite traditional BSV remaining the gold standard, DCDs provide a reasonable alternative therapy. In addition, the DCDs have a lower short-term morbidity associated with the procedure at the cost of the possible risk of higher long-term mortality. Clinical trials with more validity are required for a direct comparison between BSV and DCDs.

Construction and Validation of a New Model for the Prediction of Rupture in Patients with Intracranial Aneurysms

BACKGROUND

Despite progress in the detection of biological molecules that contribute to intracranial aneurysm (IA) development, many pathophysiological mechanisms remain unclear, particularly with regard to predicting IA rupture. In this study, we aimed to identify hub genes and construct a new model to predict IA rupture.

METHODS

Four datasets (62 ruptured IAs, 16 unruptured IAs, and 31 normal controls) were downloaded from the Gene Expression Omnibus. Differentially expressed genes (DEGs) were identified between the IAs and normal controls. All overlapping genes were analyzed using weighted gene co-expression network analysis. Functional enrichment analyses were performed using key modules. We then intersected the key module genes with DEGs. Protein-protein interaction networks were assessed to identify key hub genes. Least absolute shrinkage and selection operator logistic regression analysis was performed to construct a prediction model. A receiver operating characteristic curve was constructed to evaluate the reliability of the scoring system.

RESULTS

After intersection and normalization, 433 DEGs were identified and 15,388 genes were selected for weighted gene co-expression network analysis. The black module with 1145 genes exhibited the highest correlation with IA rupture. Many potential mechanisms are involved, such as the inflammatory response, innate immune response, extracellular exosome, and extracellular space. Thirty hub genes were selected from the protein-protein interaction, and 4 independent risk genes, TNFAIP6, NCF2, OSM, and IRAK3, were identified in the least absolute shrinkage and selection operator logistic regression model.

CONCLUSIONS

Our prediction model not only serves as a useful tool for assessing the risk of IA rupture, but the key genes identified herein could also serve as biomarkers and therapeutic targets.

Hypothalamus-Pituitary Dysfunction as an Independent Risk Factor for Postoperative Central Nervous System Infections in Patients With Sellar Region Tumors

OBJECTIVE

The purpose of this study was to verify that hypothalamus-pituitary dysfunction is one of the risk factors for postoperative central nervous system infections (PCNSIs).

METHOD

We performed a retrospective analysis of all patients with sellar region lesions who underwent surgery between January 2016 and November 2019 at Peking Union Medical College Hospital. In total, 44 age- and sex-matched controls were enrolled. Univariate and multivariate analyses were performed to identify risk factors for PCNSIs.

RESULT

We enrolled 88 patients, 44 of whom had PCNSIs. Surgical approach (TCS) (P<0.001), previous surgery on the same site (P=0.001), intraoperative cerebral spinal fluid (CSF) leakage (P<0.001), postoperative adrenal insufficiency (P=0.017), postoperative DI (P=0.004) and the maximum Na⁺ levels(<0.001) correlated significantly with PCNSIs. Multivariate analysis showed that Surgery approach (TCS)(OR: 77.588; 95%CI: 7.981-754.263; P<0.001), intraoperative CSF leakage (OR: 12.906; 95%CI: 3.499-47.602; P<0.001), postoperative DI (OR: 6.999; 95%CI:1.371-35.723; P=0.019) and postoperative adrenal insufficiency (OR: 6.115; 95%CI: 1.025-36.469; P=0.047) were independent influencing factors for PCNSIs.

CONCLUSION

TCS, intraoperative CSF leakage, postoperative DI and postoperative adrenal insufficiency are risk factors for PCNSIs in patients with sellar region tumors.

Systematic review and meta-analysis of the prevalence of venous thromboembolic events in novel coronavirus disease-2019 patients

Background

Emerging clinical evidence has shown that patients with the novel coronavirus disease-2019 (COVID-19) have complications that include venous thromboembolism (VTE), consisting of deep vein thrombosis (DVT) and pulmonary embolism (PE). The prevalence of VTE in patients hospitalized with COVID-19 is unclear.

Methods

Eligible studies on COVID-19 were collected from PubMed, Web of Science, and Embase. Patient characteristics and information were extracted for three categories of patients: consecutive, ICU, and non-ICU group. All PEs and DVTs were diagnosed by computed tomographic pulmonary arteriography and duplex ultrasound examination, respectively. A subgroup analysis of testing strategies in ICU and non-ICU patients for PE and DVT was also performed.

Results

Forty clinical studies involving 7966 patients hospitalized with COVID-19 were included. Pooled VTE prevalence was 13% in consecutive patients (95% confidence interval [CI], 0.05-0.24; I² = 97%), 7% in non-ICU patients (95% CI, 0.01-0.18; I² = 93%), and 31% in ICU patients (95% CI, 0.22-0.42; I² = 91%). ICU patients had the highest prevalence of PE among the three groups (17% [95% CI, 0.12-0.23] vs 8% in consecutive patients [95% CI, 0.04-0.13], 4% in non-ICU patients [95% CI, 0.01-0.08]). ICU patients also had the highest DVT prevalence (25% [95% CI, 0.14-0.37] vs 7% in consecutive patients [95% CI, 0.03-0.14], and 7% in non-ICU [95% CI, 0.02-0.14]). The subgroup analysis showed a three-fold improvement in the PE and DVT detection rates in both ICU and non-ICU patients with COVID-19 when the screening test for VTE was applied. In the settings of screening tests for VTE, ICU patients have a significantly higher prevalence of PE (37% vs 10%; P < .0001) and DVT (40% vs 12%; P = .0065) compared with non-ICU patients.

Conclusions

VTE is common in patients hospitalized with COVID-19, especially among ICU patients. Screening tests for PE and DVT may significantly improve detection rates in both ICU and non-ICU patients with COVID-19 than tests based on clinical suspicion.

Long noncoding RNA FAM201A mediates the metastasis of lung squamous cell cancer via regulating ABCE1 expression

OBJECTIVE

Long noncoding RNA (lncRNA) family with sequence similarity 201-member A (FAM201A) is a novel lncRNA promoting the development of various cancers. However, the biological function of FAM201A on the metastasis of lung squamous cell carcinoma (LSCC) remains unknown. The aim of this study was to explore the molecular mechanism of FAM201A and its target protein in advanced LSCC.

PATIENTS AND METHODS

Quantitative Polymerase Chain Reaction (qPCR) was applied to evaluate FAM201A expression in lung cancer tissues. The impact of high FAM201A expression on the overall survival in patients with lung cancer was tested using the log-rank test. The relevance between aberrant FAM201A and clinicopathological characteristics in patients with lung cancer was analyzed using the Chi-square tests. Cell proliferation was assayed using the Cell Counting Kit-8 (CCK-8) and a transwell assay, and the mice xenograft models were applied to determine the promoting effects of FAM201A on LSCC in vitro and in vivo. The underlying regulatory mechanism was explored through RNA transfection, qPCR, and Western blotting. The correlation between ATP-binding cassette transporter E1 (ABCE1) and FAM201A expression was verified using Spearman's correlation coefficient.

RESULTS

FAM201A is aberrantly elevated in tissues from patients with non-small cell lung cancer. High levels of FAM201A expression were more likely to present in patients with squamous type, M1 stage, and inferior overall survival. Differential expression was found between non-metastatic and metastatic squamous carcinoma, but not in adenocarcinoma. FAM201A knockdown inhibits cell proliferation, migration, and invasion of LSCC cells in vitro, and represses tumor growth in vivo. Furthermore, ABCE1 in LSCC cells was downregulated by silencing FAM201A. The tissue level of ABCE1 was positively correlated with FAM201A expression in patients with LSCC.

CONCLUSIONS

FAM201A may markedly induce migration and invasion of LSCC, resulting in the M1 stage and poor survival. These findings suggest the FAM201A-ABCE1 axis as a novel therapeutic target in LSCC.

Epidemiological Investigation of OHCWs with COVID-19

During the coronavirus disease 2019 (COVID-19) pandemic, there is an important risk of infection in health care workers, including oral health care workers (OHCWs), due to the characteristics of dental practice. In this retrospective study, data pertaining to the 31 OHCWs diagnosed with COVID-19 in Wuhan, Hubei Province, were retrieved and analyzed. Questionnaires were administered to the subjects over the Internet and telephone. Clinical and epidemiological characteristics and information on the use of personal protective equipment (PPE) were collected. There were 22 females and 9 males, with a median age of 39 y. Although the severity of most cases of COVID-19 (93.5%) was mild or moderate, 1 case was severe, and another case was critical, resulting in death. Fever was the main first symptom of COVID-19, followed by fatigue and myalgia. Most of the OHCWs routinely used PPE such as medical masks, gloves, caps, and work clothes while performing clinical work. N95 or KN95 masks were rarely available because of the scarcity of PPE during the outbreak. Nineteen OHCWs reported a contact history, among whom 7 worked in a fever clinic, 5 reported contact with dental patients suspected of having COVID-19, and 7 reported contact with family members with COVID-19–related symptoms at least 1 d earlier. Our findings indicated that there were few clusters of COVID-19 in dental settings. Since the outbreak, the Hospital of Stomatology, Wuhan University, has provided emergency dental treatment, and none of their staff were infected while providing dental service, which indicates that comprehensive measures such as the use of advanced PPE and environmental disinfection can prevent cross-infection in dental practice. The analysis of the procedures followed during the emergency treatments indicated that OHCWs preferred to recommend conservative treatment to patients, suggesting that attention should be paid to the psychological impact of COVID-19 on dental practitioners.

MSC-derived exosomes promote recovery from traumatic brain injury via microglia/macrophages in rat

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality in young individuals worldwide. There is currently no effective clinical treatment for TBI, but mesenchymal stem cell-derived exosomes have exhibited promising therapeutic effects. In this study, we performed intracerebroventricular microinjection of human adipose mesenchymal stem cell (hADSC)-derived exosomes (hADSC-ex) in a weight-drop-induced TBI rat model. We found that hADSC-ex promoted functional recovery, suppressed neuroinflammation, reduced neuronal apoptosis, and increased neurogenesis in TBI rats. The therapeutic effects of hADSC-ex were comparable to those of hADSC. Sequential in vivo imaging revealed increasing aggregation of DiR-labeled hADSC-ex in the lesion area. Immunofluorescent staining of coronal brain sections and primary mixed neural cell cultures revealed distinct overlap between CM-DiI-labeled hADSC-ex and microglia/macrophages, indicating that hADSC-ex were mainly taken up by microglia/macrophages. In a lipopolysaccharide-induced inflammatory model, hADSC-ex suppressed microglia/macrophage activation by inhibiting nuclear factor κB and P38 mitogen-activated protein kinase signaling. These data suggest that hADSC-ex specifically enter microglia/macrophages and suppress their activation during brain injury, thereby inhibiting inflammation and facilitating functional recovery. They also offer new insight into the cellular targeting, uptake and migration of hADSC-ex, and provide a theoretical basis for new therapeutic strategies for central nervous system diseases.

[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.

Differential roles of Scavenger receptor class B type I: A protective molecule and a facilitator of atherosclerosis (Review)

The scavenger receptor class B type I (SR-BI) is a multi-ligand membrane protein receptor that binds to high-density lipoprotein (HDL) under physiological conditions, promoting the selective uptake of cholesterol esters from HDL into cells. SR-BI also promotes the reverse transport of excess cholesterol from peripheral tissues to the liver, contributing to the synthesis of bile acids for excretion and the removal of excess cholesterol from the body, thereby lowering the cholesterol load and exerting anti-atherosclerotic effects. Studies in mice and humans have demonstrated that a functional defect of SR-BI can cause atherosclerotic lesions and cardiovascular diseases, such as myocardial infarction and stroke. Additionally, SR-BI in vascular endothelial cells promoted the deposition of low-density lipoprotein under the endothelium. Although SR-BI is widely expressed in various tissues and cell types throughout the body, its expression level and function vary accordingly. The present review focuses on the biological functions and mechanisms of SR-BI in regulating atherosclerosis.

Molecular catalysis of CO2 reduction: recent advances and perspectives in electrochemical and light-driven processes with selected Fe, Ni and Co aza macrocyclic and polypyridine complexes

Earth-abundant Fe, Ni, and Co aza macrocyclic and polypyridine complexes have been thoroughly investigated for CO2 electrochemical and visible-light-driven reduction. Since the first reports in the 1970s, an enormous body of work has been accumulated regarding the two-electron two-proton reduction of the gas, along with mechanistic and spectroscopic efforts to rationalize the reactivity and establish guidelines for structure-reactivity relationships. The ability to fine tune the ligand structure and the almost unlimited possibilities of designing new complexes have led to highly selective and efficient catalysts. Recent efforts toward developing hybrid systems upon combining molecular catalysts with conductive or semi-conductive materials have converged to high catalytic performances in water solutions, to the inclusion of these catalysts into CO2 electrolyzers and photo-electrochemical devices, and to the discovery of catalytic pathways beyond two electrons. Combined with the continuous mechanistic efforts and new developments for in situ and in operando spectroscopic studies, molecular catalysis of CO2 reduction remains a highly creative approach.

Diagnosis and treatment of low T3 syndrome in neurocritical patients

WHAT IS KNOWN AND OBJECTIVE

Low levels of serum triiodothyronine (T3) are a strong predictor of mortality and poor prognosis in critical care patients. Few reports, however, have focused on neurocritical patients. The application of hormone replacement therapy (HRT) in the treatment of neurocritical patients with low T3 syndrome remains controversial. We studied the role of low T3 state as a predictor of outcomes in neurocritical patients and examined the effect of HRT on prognosis.

METHODS

A retrospective analysis was performed on the data of 32 neurocritical patients with low T3 syndrome who were admitted to the neuro-intensive care unit of Peking Union Medical College Hospital between January 2012 and October 2018. While 18/32 (56.25%) patients received HRT (HRT group; n = 18), 14/32 (43.75%) patients did not receive HRT (non-HRT group; n = 14). Patients were followed up for periods ranging from 3 months to 72 months. Baseline clinical and laboratory data were compared between the two groups using Mann-Whitney U tests or the t tests. Overall survival was assessed by Kaplan-Meier curve and compared by log-rank tests. Univariate and multivariate regression analyses were performed to identify the factors associated with prognosis and estimate the effect of HRT. We also assessed the influence of HRT on final neurological function, using the Glasgow Coma Scale (GCS) and the Glasgow Outcome Scale (GOS) scores.

RESULTS AND DISCUSSION

The neurocritical events in our cohort included post-operative complications (n = 18), traumatic brain injury (n = 8) and spontaneous intracerebral haemorrhage (n = 6). Mean GCS score in the cohort was 6.41 (6.44 ± 3.14 in HRT group vs 6.36 ± 2.06 in non-HRT group). A total of 15/32 (46.87%) deaths were recorded (7 in the HRT group, 8 in the non-HRT group). In the HRT group, 15 patients underwent repeat thyroid function tests after completion of HRT; the low T3 situation was corrected in only 5/15 (33.3%) patients. Overall survival was significantly shorter in the non-HRT group than in the HRT group (16.45 months vs 47.47 months; P = .034). In univariate regression analysis, the HRT group has the lower mortality risk than the non-HRT group (HR = 0.301, 95% Cl: 0.094-0.964; P = .043). However, multivariate regression analysis showed no significant difference in mortality risk between the two groups (HR = 0.340 95% CI: 0.099-1.172; P = .087). There was no significant difference in effects of HRT on the short- and long-term neurological function between the groups.

WHAT IS NEW AND CONCLUSION

Low T3 syndrome may influence the prognosis of neurocritical patients, attention should be paid to the changes in serum T3 levels during treatment. Although it is unclear to what extent HRT can improve the short or long-term outcomes of neurological function, it can significantly improve the survival rates of neurocritical patients.

Cigarette smoke exposure impairs lipid metabolism by decreasing low-density lipoprotein receptor expression in hepatocytes

BACKGROUND

Cigarette smoke (CS) exposure impairs serum lipid profiles and the function of vascular endothelial cells, which accelerates the atherosclerosis. However, the precise mechanism and effect on the expression of low-density lipoprotein receptor (LDLR) in the liver by CS exposure is still unclear.

METHODS

In this study, adult male C57BL/6 J mice were divided into three groups, with one group being exposed to CS for 6 weeks. HepG2 cells were treated with CS extract at concentrations of 1, 2.5, 5, and 10%.

RESULTS

The serum levels of total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C) for the CS-exposure group were significantly higher than those in the control group (P < 0.05). Moreover, CS exposure decreased the LDLR expression in the hepatocytes and promoted inflammation in the blood vessel walls. Melatonin was intraperitoneally injected at 10 mg/kg/d for 6 weeks alongside CS exposure, and this significantly decreased the levels of TC, TGs, and LDL-C and decreased the expression of intercellular adhesion molecule-1 and the infiltration of cluster determinant 68-cells. In vitro, CS extract prepared by bubbling CS through phosphate-buffered saline decreased the LDLR expression in HepG2 cells in a time- and concentration-dependent manner, and this effect was prevented by pretreatment with 100 μM melatonin.

CONCLUSIONS

In conclusion, CS exposure impaired lipid metabolism and decreased LDLR expression in hepatocytes, and these effects could be prevented by melatonin supplementation. These findings implied that melatonin has the potential therapeutic applicability in the prevention of lipid metabolic disorder in smokers.

Therapeutic Potential of Endothelial Colony Forming Cells Derived from Human Umbilical Cord Blood

Endothelial progenitor cells (EPCs) are implicated in multiple biologic processes such as vascular homeostasis, neovascularization and tissue regeneration, and tumor angiogenesis. A subtype of EPCs is referred to as endothelial colony-forming cells (ECFCs), which display robust clonal proliferative potential and can form durable and functional blood vessels in animal models. In this review, we provide a brief overview of EPCs' characteristics, classification and origins, a summary of the progress in preclinical studies with regard to the therapeutic potential of human umbilical cord blood derived ECFCs (CB-ECFCs) for ischemia repair, tissue engineering and tumor, and highlight the necessity to select high proliferative CB-ECFCs and to optimize their recovery and expansion conditions.

[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.

Generation of a neutralizing antibody against RD114-pseudotyped viral vectors

The feline endogenous RD114 glycoprotein has proved to be an attractive envelope to pseudotype both retroviral and lentiviral vectors. As a surface protein, its detection on packaging cells as well as viral particles would be useful in different fields of its use. To address this, we generated a monoclonal antibody against RD114 by immunization of rats, termed 22F10. Once seroconversion was confirmed, purified 22F10 was cloned into murine Fc and characterized with a binding affinity of 10nM. The antibody was used to detect RD114 and its variant envelopes on different stable viral packaging cell lines (FLYRD18 and WinPac-RD). 22F10 was also shown to prevent the infections of different strains of RD-pseudotyped vectors but not related envelope glycoproteins by blocking cell surface receptor binding. We are the first to report the neutralization of viral particles by a monoclonal αRD114 antibody.

[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.