[The clinical characteristics of 497 children with congenital pseudarthrosis of the tibia].

Objective: To investigate the clinical and radiologic characteristics of children with congenital pseudarthrosis of the tibia (CPT) in a single center. Methods: This is a retrospective case series study. According to inclusion and exclusion criteria, clinical data of 497 children(507 limbs) with CPT who were treated at Department of Orthopedics, the Children's Hospital Affiliated to Xiangya School of Medicine, Central South University from January 2011 to December 2020 were collected. Baseline data included gender, age at initial visit, age at onset of symptoms, accompanying symptoms, domicile, whether first treated at our hospital, and treatment-related information such as surgical or conservative treatment, surgical complications, etc., were extracted and analyzed using the health information system. Imaging data of the children, including Crawford classification, bilateral leg lengths, presence of fibular pseudarthrosis, and location of pseudarthrosis along the tibia segment, were analyzed using the Picture Archiving and Communication System. Data were compared using independent sample t test or χ2 tests. Results: Among 497 children with CPT, there were 305 males (61.4%) and 192 females (38.6%). The age at initial visit was (3.6±3.2) years (range: 0.1 to 16.2 years). Neurofibromatosis type 1 (NF1) symptoms were positive in 340 children (68.4%), and negative in 157 children (31.6%). Among NF1-positive children, those with symptoms onset before 1 year of age were significantly more than NF1-negative children (74.1%(252/340) vs. 66.2%(104/157);χ2=9.24, P=0.001), and the proportion of fractures (92.9%,316/340) was significantly higher than that in the NF1-negative group (84.7%,133/157) (χ2=8.33, P=0.004). According to imaging data, Crawford type Ⅳ was the most common type, with 321 limbs (63.3%), followed by type Ⅱ in 100 limbs (19.7%), type Ⅲ in 54 limbs (10.7%) and type Ⅰ in 32 limbs (6.3%). Pseudarthrosis occurred in the proximal third of the tibia in 14 limbs (2.8%), in the middle third in 185 limbs (36.5%), and in the distal third in 308 limbs (60.8%). Seventy-four children (14.9 %) had associated fibular pseudarthrosis. The lateral proximal tibial angle was 86.91°±5.21°(range: 72.17° to 102.08°), and the lateral distal tibial angle was 87.27°±10.73°(range: 51.07° to 128.17°). A total of 421 children (84.7%) underwent surgical treatment with (3.1±2.4) surgeries performed per child (range:0 to 12 surgeries); 76 children (15.3%) received conservative treatment. Postoperative complications mainly included ankle valgus (77 cases), leg length discrepancy (71 cases),refracture (48 cases), osteomyelitis (11 cases), and hardware failure (10 cases). NF1-positive children underwent more surgeries than NF1-negative children ((5.1±2.2)times vs.(2.1±1.8)times;t=14.93,P<0.01). Conclusions: Crawford type Ⅳ is the most common type of CPT in children in this study. CPT predominantly occurs in the middle or distal third of the tibia. The majority of children with CPT experienced symptoms and were seen at outpatient clinics before the age of 3 years. The main surgical complications currently associated with CPT treatment are ankle valgus and leg length discrepancy. Compared with CPT without NF1, children with NF1-positive CPT tend to have earlier symptom onset and may require more frequent treatments.

Shear stress-induced MMP1 and PDE2A expressions in coronary atherosclerosis.

AIM: Biomechanical stress plays an essential role in coronary atherosclerosis (CAS), however, inter-relations between mechanical conditions and gene expressions remain unclear. METHODS: We constructed finite element model of CAS to map human wall shear stress (WSS). Biopsy aortic tissue samples were obtained from 3 CAS patients. Gene expression pattern in CAS was analyzed by GEO datasets. Immunofluorescence staining and western blot confirmed protein expression and localization. RESULTS: Peak WSS was significantly increased in the vessel stenosis of CAS at 0.25 s (mean 55.1 Pa). Analyses results of GSE76275 showed matrix metalloproteinases1 (MMP1) and phosphodiesterase-2A (PDE2A) up-regulation in endothelial shear responsiveness, which was further validated and localized in vascular endothelial cells, smooth muscle cells and other cells by double immunofluorescence staining. Western blotting assay demonstrated up-regulation of MMP1 and PDE2A expression dependent on the WSS. CONCLUSIONS: MMP1 and PDE2A up-regulations rely on increased WSS in development and risk of CAS, suggesting that their elevation may be potential target for diagnosis and treatment (Fig. 3, Ref. 28).

[The prevalence and risk factors of anemia in a general population from Kailuan in north China].

Objective: To analyze the prevalence and risk factors of anemia in a general population in Kailuan. Methods: Working and retired employees in Kailuan Company who had participated in biennial physical examination from 2006-2014 were investigated by questionnaire and blood test. Hemoglobin levels<120 g/L in male and<110 g/L in female are defined as anemia. The trend of prevalence of anemia was analyzed by chi square test. Multivariable logistic regression was used to analyze the factors associated with anemia. Results: (1) The biennial prevalence of anemia in Kailuan during 2006-2014 were 3.7%, 3.1%, 2.4%, 1.3%, 1.5%. The corresponding proportion were 3.3%, 2.3%, 1.9%, 0.8%, 1.0% in males and 5.3%, 5.9%, 4.2%, 3.1% and 3.3% in females, respectively. The differences between males and females were statistically significant (all P<0.05). The prevalence of anemia declined over time (P for trend<0.05). (2) The results of multivariable logistic regression showed that aging and elevated hs-CRP were positively associated with anemia, with OR= 1.01 (95%CI 1.01-1.02) and 1.03 (95%CI 1.02-1.03) , respectively. While male, BMI, physical exercise, smoking, hyperlipidemia were negatively associated with anemia with OR= 0.60 (95%CI 0.55-0.65) , 0.99 (95%CI 0.98-0.99) , 0.91 (95%CI 0.82-0.98) , 0.87 (95%CI 0.81-0.95) and 0.87 (95%CI 0.81-0.94) , respectively. Conclusions: The prevalence of anemia in a large general population in Kailuan has been analyzed. Prevalence of anemia is higher in males than females and declines over time. Several demographic and clinical characteristics are associated with anemia.

[Role of bone marrow mesenchymal stem cells with CTLA4Ig and CD40LIg gene modification in rejection reaction after liver transplantation].

Objective: To investigate the role of bone marrow mesenchymal stem cells (BMSCs) with CTLA4Ig and CD40LIg gene modification in rejection reaction after liver transplantation in rats and possible mechanisms. Methods: The modified Kamada's two-cuff technique was used to establish a Lewis-BN rat model of orthotopic liver transplantation, and a total of 75 rats were randomly divided into groups A, B, C, D, and E, with 15 rats in each group. The rats in group A (control group) were given infusion of isotonic saline via the portal vein during liver transplantation, those in group B (BMSC group) were given infusion of BMSCs via the portal vein during liver transplantation, those in group C (BMSCs with CTLA4Ig gene modification) were given infusion of BMSCs carrying the CTLA4Ig gene via the portal vein during liver transplantation, those in group D (BMSCs with CD40LIg gene modification) were given infusion of BMSCs carrying the CD40LIg gene via the portal vein during liver transplantation, and those in group E (BMSCs with CTLA4Ig and CD40LIg gene modification) were given infusion of BMSCs carrying CTLA4Ig and CD40LIg gene modification via the portal vein during liver transplantation. Postoperative survival and change in liver function were observed. HE staining was used to observe the pathomorphological changes of the graft liver, and ELISA was used to measure the levels of interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-10 (IL-10), and interferon-γ (IFN-γ) in peripheral blood. A one-way analysis of variance was used for comparison of means of multiple samples, and the Kaplan-Meier survival curve analysis was used for comparison of survival rates between multiple groups. Results: Group E had a significantly longer survival time after surgery than groups A, B, C, and D (P < 0.05), groups C and D had a significantly longer survival time than groups A and B (P < 0.05), and there was no significant difference between groups C and D (P > 0.05). On day 10 after surgery, group A had significantly higher levels of alanine aminotransferase and total bilirubin than the other four groups (P < 0.05). HE staining showed severe rejection reaction in group A, moderate rejection reaction in group B, and mild rejection reaction in groups C and D; pathological examination showed no marked rejection reaction in group E. Group A had significant increases in the levels of IL-2 and IFN-γ and significant reductions in the levels of IL-4 and IL-10 after surgery compared with the other four groups (all P < 0.05). Conclusion: Infusion of BMSCs with modification of both CTLA4Ig and CD40LIg genes can significantly inhibit acute rejection reaction after liver transplantation in rats and effectively prolong the survival time of the graft liver, with a better effect than infusion of BMSCs alone or BMSCs with modification of CTLA4Ig or CD40LIg gene.

Osteoblast differentiation of rabbit adipose-derived stem cells by polyethylenimine-mediated BMP-2 gene transfection in vitro.

The aim of this study was to examine the efficiency of polyethylenimine-mediated transfection of the human bone morphogenetic protein-2 (BMP-2) gene into rabbit adipose-derived stem cells (ADSCs), and its effect on osteoblast differentiation. Adipose tissue was isolated from the necks of adult Japanese white rabbits and cultured in vitro to obtain ADSCs. Gene delivery of BMP-2 was mediated by polyethylenimine and stable transformants were selected by G-418. The expression of BMP-2 mRNA was confirmed by reverse transcription-polymerase chain reaction, and of the BMP-2 protein by ELISA. Osteocalcin and collagen type I were detected by western blot and by an alkaline phosphatase kit. Alizarin red S stain was also utilized to examine osteogenesis. The non-transfected group was considered as a control. In this study, we successfully derived ADSCs from rabbit adipose tissue. Through passages 3-6, the expression of CD29 and CD44 gradually increased, whereas the expression of CD34 and CD45 gradually decreased. Both mRNA and protein expression of BMP-2 were confirmed following polyethylenimine-mediated BMP-2 gene delivery. In addition, the expression of alkaline phosphatase, osteocalcin, and collagen type I was found to be upregulated and alizarin red S staining was positive in transfected ADSCs, indicating BMP-2-induced osteogenesis. Therefore, this study determined that polyethylenimine was able to mediate BMP-2 gene delivery and induce osteogenic differentiation of ADSCs.

Identification of a novel LEMD3 Y871X mutation in a three-generation family with osteopoikilosis and review of the literature.

INTRODUCTION: Osteopoikilosis is a rare and benign autosomal dominant genetic disorder, characterized by a symmetric but unequal distribution of multiple hyperostotic areas in different parts of the skeleton. Recent studies have reported loss-of-function mutations in the LEM domain containing 3 (LEMD3) gene, encoding an inner nuclear membrane protein, as a cause of osteopoikilosis. METHODS: We investigated LEMD3 gene in a three-generation family from China, with six patients affected with osteopoikilosis. Peripheral blood samples were collected from family members and 100 healthy controls. All exons of the LEMD3 gene and adjacent exon-intron sequences were amplified by PCR and subsequently sequenced. RESULTS: A novel heterozygous c.2612_2613insA (p.Y871X) mutation in exon 13 of LEMD3 was identified, which resulted in a frame shift predicted to generate a premature stop codon at amino acid position 871. The mutation co-segregates with the osteopoikilosis phenotype and was not found in 100 ethnically matched controls. CONCLUSION: We identified a new mutation in LEMD3 gene, accounting for the familial case of osteopoikilosis. In addition we also review the clinical manifestation, diagnosis and treatment of osteopoikilosis.

Effect of compound Maqin decoction on TGF-ß1/Smad proteins and IL-10 and IL-17 content in lung tissue of asthmatic rats.

In this research, compound Maqin decoction (CMD) has been shown to positively affect in airway inflammation of asthma models. We evaluated the effects of CMD on the expression of transforming growth factor (TGF)-ß1/Smad proteins, interleukin (IL)-17, and IL-10 in lung tissue of asthmatic rats. Asthma was induced in a rat model using ovalbumin. After a 4-week treatment with CMD, rats were killed to evaluate the expression of TGF-ß1 and Smad proteins in lung tissue. IL-10 and IL-17 levels in lung tissue homogenates were determined by ELISA. The expression of TGF-ß1 and Smad3 protein increased, whereas expression of Smad7 protein decreased upon high-dose or low-dose treatment with CMD or by intervention with dexamethasone, compared to the control. There was a significant difference between treatment with a high dose CMD and the control treatment, but no significant difference was found between high-dose CMD treatment and dexamethasone intervention. The expression of TGF-ß1 and Smad7 protein increased, whereas the expression of Smad3 protein decreased in the model group compared to other groups. In the CMD high-dose group, low-dose group, and dexamethasone intervention group, the IL-17 concentrations in lung tissue homogenates were decreased, while IL-10 levels were increased. Again, there was a significant difference between CMD high-dose and control treatment, but not between CMD high-dose treatment and dexamethasone intervention. Thus, positive effects of CMD against asthmatic airway remodeling may be due to its regulatory effect on TGF-ß1, Smad3, and Smad7 protein levels and on cytokines such as IL-10 and IL-17.

Important roles of public playgrounds in the transmission of hand, foot, and mouth disease.

Intra-home and kindergarten transmissions were the reported major modes of hand, foot, and mouth disease (HFMD) transmission in preschool children. However, infection at home is not common and 65-80% of cases do not attend preschool. We conducted a matched case-control study to explore the role of public playgrounds in the transmission of HFMD in addition to direct and indirect exposure to HFMD patients. We used 156 hospital source cases and 156 community source controls. Univariate analysis was followed by conditional logistic regression with attributable fraction computed. Adjusted odds ratios were 11·70 [95% confidence interval (CI) 1·26-109·40] for having HFMD cases in the same class, 14·19 (95% CI 3·55-56·74) for having HFMD cases within the 20 nearest neighbourhoods, 6·03 (95% CI 2·84-12·80) for exposure to public playgrounds, 2·13 (95% CI 1·05-4·32) for finger sucking and 0·29 (95% CI 0·11-0·78) for hand washing with soap before meals. The attributable fractions for the first four risk factors were 6·4%, 20·9%, 57·2% and 27·5%, respectively, while the population prevented fraction for hand washing with soap before meals was 18·7%. Based on our findings, hand washing with soap should be advocated. Health education could include topics which underline the precautions which need to be taken and the advice given regarding avoiding the use of public playgrounds during epidemic periods, especially when children have been getting sick.

Effects of washed platelets vs platelet-rich plasma on the proliferation and mineralization of rat dental pulp cells.

We examined the effects of washed platelets (WPLTs) and platelet-rich plasma (PRP) on the proliferation and mineralization of rat dental pulp cells. Rat dental pulp cells were separated, cultured, and identified. Medium containing 1, 10, 100, or 500 mL/L PRP or WPLTs was added to 4th generation cells. The MTS method was used to determine cell proliferation. Alizarin red staining was used to observe the formation of mineralized nodules after cell mineralization and induction for 10 and 20 days under different culture conditions, and the areas of the mineralized nodules formed 20 days after induction were computed. The addition of 1, 10, and 100 mL/L WPLTs or PRP significantly promoted rat dental pulp cell proliferation (P < 0.05) whereas 500 mL/L WPLTs or PRP had no significant effect (P > 0.05). Under the same concentrations, no significant differences on cell proliferation were observed between WPLT and PRP treatments (P > 0.05 in all groups). After 10 days mineralization and culture, the 100 and 500 mL/L WPLT and PRP group positive nodule rates were significantly higher than those of the low concentration and the control groups (P < 0.05). After 20 days, the areas of the mineralized nodules formed in the 100 and 500 mL/L WPLT and PRP groups were significantly larger than those in the control group (P < 0.05). These results demonstrate that both WPLTs and PRP are equally able to significantly promote the proliferation and calcification of rat dental pulp cells under a certain range of concentrations.

Differential gene expression in pre-laying and laying period ovaries of Sichuan White geese (Anser cygnoides).

Geese are an economically important poultry species worldwide. Their superior meat production performance and meat qual-ity make them a popular food. However, they are not bred worldwide because their poor laying capacity increases farming costs. To gain a global view of the genes that are differentially expressed between pre-laying (P) and laying (L) periods and to develop a database for further studies, we performed large-scale transcriptome sequencing of ovarian tissue collected from Anser cygnoides. In total, 30,151,422 raw reads, with an average length of 151 bp and a total length of 4,552,864,722 bp, were obtained. After primers and adaptors were removed, 19,167,132 clean reads, with an average length of 134.5 bp and a total length of 2,577,297,281 bp, were obtained, among which 1,268,906,694 bp and 1,308,390,587 bp were from L and P ovarian tissue, respectively. The 16,605 assembled sequences were further functionally annotated by comparing their sequences to different protein and functional domain databases and assigning gene ontology (GO) terms. Of these, 511 as-sembled sequences were considered differentially expressed based on the 2-fold method, among which 396 were assigned at least one GO term. Digital expression analysis using the Kyoto encyclopedia of genes and genomes annotation identified 121 genes that were differ-entially expressed in the P vs L periods. Five of these are of special interest for further investigation of their roles in determining high re-productive performance. This study provides valuable information and sequence resources for uncovering genes determining high egg-laying performance and for future functional genomics analysis of geese.

Treatment of domestic sewage by a metal membrane bioreactor.

A submerged flat metal MBR (membrane bioreactor) was used to treat synthetic domestic sewage in this study. The experiment was continued for 270 days and ran under two modes as AMBR (aerobic membrane bioreactor) and A/O-MBR (anoxic/aerobic membrane bioreactor) at a permeate flux of 0.4-1 m³/(m² d). PVA (polyvinyl alcohol) gel beads were added to the aeration tank with a volume ratio of 10% at the end of the A/O-MBR mode. The mean COD and TN removal efficiencies achieved 96.69 and 32.12% under the AMBR mode, and those were 92.17 and 72.44% under the A/O-MBR mode, respectively. SND (simultaneous nitrification and denitrification) occurred at high MLSS (mixed liquor suspended solids) concentration. The metal membranes reduced effluent COD during filtration. The system ran stably for 115 days at a permeate flux of 0.8-1 m³/(m² d) without changing membranes under the AMBR mode, but the membrane filterability decreased gradually under high MLSS or A/O-MBR mode, and the addition of PVA worsened the membrane filterability on the contrary. PSD (particle size distribution) and sludge fractions had evident influence on membrane fouling. The main fouling mechanism was cake formation under the AMBR mode, and that was pore blocking under the A/O-MBR mode.

Termination of two-dimensional metallic conduction near the metal-insulator transition in a Si/SiGe quantum well.

We report in this Letter our recent low-temperature transport results in a Si/SiGe quantum well with moderate peak mobility. An apparent metal-insulating transition is observed. Within a small range of densities near the transition, the conductivity σ displays a nonmonotonic temperature dependence. After an initial decrease at high temperatures, σ first increases with decreasing temperature T, showing a metallic behavior. As T continues decreasing, a downturn in σ is observed. This downturn shifts to a lower T at higher densities. More interestingly, the downturn temperature shows a power-law dependence on the mobility at the downturn position, suggesting that a similar downturn is also expected to occur deep in the apparent metallic regime at albeit experimentally inaccessible temperatures. This thus hints that the observed metallic phase in 2D systems might be a finite temperature effect.

[Clinical features and treatment outcome of patients with non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis].

Objective: To investigate the clinical features and effect of prognostic factors in patients with different pathological types of non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis. Methods: We collected and analyzed the clinical data of 89 patients with non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis who were treated at Huadong Hospital from March 2013 to May 2020. The data were analyzed via log-rank and Cox multivariate analyses. Results: The median overall survival time of the 89 cases was 10.2 months. Patients with B-cell lymphoma-associated hemophagocytic lymphohistiocytosis did not reach the median overall survival time. The median overall survival times of T-cell lymphoma-associated hemophagocytic lymphohistiocytosis and NK-cell lymphoma-associated hemophagocytic lymphohistiocytosis were 10.2 and 3.0 months, respectively. The pathological type of non-Hodgkin lymphoma (OS: P=0041, PFS: P=0.015) , ECOG score ≥ 3 (OS: P=0.031, PFS: P=0.030) , hematopoietic stem cell transplantation (OS: P=0.005, PFS: P=0.040) , lymphadenopathy (OS: P=0.007, PFS: P=0.012) , and splenomegaly (OS: P=0.276, PFS: P=0.324) were related to the overall survival and progression-free survival of patients with non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis. Splenectomy could improve the prognosis of patients with lymphoma-associated hemophagocytic lymphohistiocytosis, especially T-cell lymphoma-associated hemophagocytic lymphohistiocytosis. Conclusion: The clinical characteristics of patients with different pathological types of non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis were similar but were different in the overall survival rate and the effect of prognostic factors. We suggested that patients with non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis should receive more than combined chemotherapy. To improve the prognosis and survival rate of patients, those with B-cell lymphoma-associated hemophagocytic lymphohistiocytosis and NK-cell lymphoma-associated hemophagocytic lymphohistiocytosis promptly require hematopoietic stem cell transplantation. Moreover, patients with T-cell lymphoma-associated hemophagocytic lymphohistiocytosis should consider splenectomy.

Light emission from silicon.

The possibility induction of light emission from silicon, an indirect bandgap material in which radiative transitions are unlikely, raises several interesting and technologically important possibilities, especially the fabrication of a truly integrated optoelectronic microchip. In this article, the natural considerations that constrain silicon from emitting light efficiently are examined, as are several engineered solutions to this limitation. These include intrinsic and alloy-induced luminescence; radiatively active impurities; quantum-confined structures, including zone folding and the recent developments in porous silicon; and a hybrid approach, the integration of direct bandgap materials onto silicon.

Comparative study of polyvinylidene fluoride and PES flat membranes in submerged MBRs to treat domestic wastewater.

Two kinds of membranes, polyvinylidene fluoride (PVDF) and polyethersulfone (PES), were used in submerged flat membrane bioreactors (MBRs) to treat domestic wastewater in this study. The MBRs ran under the same reactor structure, the same membrane pore size of 0.45 mICROm and the same anoxic/ oxic (A/O) process. The experimental results showed that: (1) With the influent of BOD(5) 200-500 mg/L and COD(Cr) 400-1,000 mg/L, PVDF MBR achieved the removal efficiencies of BOD(5) 96-98% and COD(Cr) 89-98%, and those were 97-99% and 93-97% in PES MBR. The interceptive efficiency of PES membrane to BOD(5) and COD(Cr) was superior to PVDF membrane. (2) The removal efficiencies of TN and NH(3)-N in two MBRs exhibited good results which were greater than 85%. The removal efficiencies of TP were greater than 80% in both MBRs. (3) MLSS concentration changed from 2,000 mg/L to 7,000 mg/L during the experiment. PES membrane was not washed and the membrane flux was steady. However, the flux of PVDF one decreased quickly and was washed for twice. It meant that PES membrane had fine capability than PVDF one.

Analgesic effect of dezocine in different doses on elderly patients undergoing abdominal operation under general anesthesia and its influence on stress response to postoperative tracheal extubation.

OBJECTIVE: To study the analgesic effect of dezocine in different doses on elderly patients undergoing abdominal operation under general anesthesia and to investigate the influence of dezocine on stress response to postoperative tracheal extubation. PATIENTS AND METHODS: A total of 76 elderly patients undergoing abdominal operation under general anesthesia and postoperative analgesia in our hospital from January 2015 to January 2016 were selected, and patients treated with fentanyl were selected as the control group (fentanyl: 10 µg/kg, n=19). The patients were randomly divided into low-dose group (dezocine: 0.05 mg/kg, n=19), medium-dose group (dezocine: 0.1 mg/kg, n=19) and high-dose group (dezocine: 0.15 mg/kg, n=19). The patients in each group were intravenously injected with 0.1 mg/kg tropisetron. The tracheal catheter was withdrawn from patients in each group; the heart rate (HR), respiratory rate (RR), mean arterial pressure (MAP) and saturation of pulse oxygen (SpO2) of patients in each group before and at 10 min after tracheal extubation were recorded in detail; moreover, the visual analogue scale (VAS) score, Ramsay sedation score, occurrence rate of adverse reactions, Bruggrmann comfort scale (BCS) score and times of pressing analgesia pump after operation of patients in the four groups were evaluated at 4, 8, 12, 24 and 48 h after operation. RESULTS: Compared with those before operation, there were no statistically significant differences in HR, RR, MAP and SPO2 of patients in low-dose group, medium-dose group and high-dose group at 10 min after tracheal extubation, and HR, RR, MAP and SPO2 of patients in control group were significantly increased after tracheal extubation (p<0.05). The VAS scores of patients in low-dose group within 48 h were significantly higher than those in control group, medium-dose group and high-dose group (p<0.05). The Ramsay sedation scores of patients in low-dose group and medium-dose group were significantly lower than those in control group and high-dose group (p<0.05), and the BCS score of patients in low-dose group was lower than those in medium-dose group, high-dose group, and control group (p<0.05). Besides, the occurrence rates of postoperative adverse reactions of patients in control group and low-dose group were higher than those in medium-dose group and high-dose group (p<0.05), the times of pressing analgesia pump after operation of patients in low-dose group were more than those in control group, medium-dose group and high-dose group (p<0.05), and the times were reduced successively in low-dose group, medium-dose group, and high-dose group. Finally, the results of correlation analysis showed that the dose of dezocine was positively correlated with the Ramsay sedation score, but negatively correlated with the VAS score of patients. CONCLUSIONS: Dezocine can effectively enhance the analgesic effect on elderly patients receiving abdominal operation under general anesthesia in a dose-dependent manner. Moreover, dezocine can significantly reduce the stress response of elderly patients to postoperative tracheal extubation, and reduce the occurrence rate of adverse complications after abdominal operation under general anesthesia.

[A multicenter, retrospective study of pathogenic bacteria distribution and drug resistance in febrile neutropenic patients with hematological diseases in Shanghai].

Objective: To investigate the pathogen spectrum distribution and drug resistance of febrile neutropenic patients with hematological diseases in Shanghai. Methods: A retrospective study was conducted on the clinical isolates from the febrile neutropenic patients hospitalized in the departments of hematology in 12 general hospitals in Shanghai from January 2012 to December 2014. The drug susceptibility test was carried out by Kirby-Bauer method. WHONET 5.6 software was used to analyze pathogenic bacteria and drug susceptibility data. Results: A total of 1 260 clinical isolates were collected from the febrile neutropenic patients. Gram-positive bacteria accounted for 33.3% and Gram-negative bacteria accounted for 66.7%. Klebsiella pneumoniae (12.5%) , Stenotrophomonas maltophilia (9.5%) , Escherichia coli (9.1%) , Pseudomonas aeruginosa (8.7%) , Acinetobacter baumannii (6.6%) , Staphylococcus aureus (5.6%) and Enterococcus faecium (5.0%) were ranked in the first 7 of all pathogens. In the respiratory tract secretions specimens, non-fermented strains accounted for 56.2%. Stenotrophomonas maltophilia accounted for 15.2%. Enterobacteriaceae and coagulase-negative Staphylococci accounted for 42.3% (104/246) and 32.6% (85/246) respectively in blood samples. Enterobacteriaceae and Enterococcus bacteria accounted for 39.4% (76/193) and 28.5% (55/193) respectively in pus specimens. The detection rates of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative Staphylococci (MRCNS) were 54.3% and 82.5%, respectively. Staphylococcus bacterial strain was not found to be resistant to linezolid, vancomycin and teicoplanin. The detection rate of Enterococcus vancomycin-resistant strains was 8.9%. Enterococcus was not detected resistance to oxazolidinone strains. Enterobacteriaceae bacteria were highly sensitive to carbapenems. The resistance rate of Pseudomonas aeruginosa to imipenem and meropenem was 34.1% and 15.8%, respectively. Stenotrophomonas maltophilia was more sensitive to minocycline hydrochloride, levofloxacin and sulfamethoxazole. The resistance rate of Acinetobacter baumannii only to cefoperazone-sulbactam was less than 10.0%. The antibiotic resistance rate of Klebsiella pneumoniae, Stenotrophomonas maltophilia, Pseudomonas aeruginosa and Acinetobacter baumanii to most of common antibiotics was lower than that of the CHINET surveillance. Conclusions: The pathogenic strain distribution in common infection sites of febrile neutropenic patients was characterized. Bacterial resistance surveillance was better than the CHINET nationwide large sample surveillance in China.

Note: A new regulation method of stable operation of high power cathode ion source.

The hot cathode ion source will tend to be unstable when operated with high power and long pulse. In order to achieve stable operation, a new regulation method based on the arc power (discharge power) feedback control was designed and tested on the hot cathode ion source test bed with arc discharge and beam extraction. The results show that the new regulation method can achieve stable arc discharge and beam extraction. It verifies the success of feedback control of arc source with arc power.

Regulation of Agrobacterium tumefaciens virulence gene expression: isolation of a mutation that restores virGD52E function.

Expression of Agrobacterium tumefaciens virulence (vir) genes is controlled by virA, virG, and a plant inducer. Isolation of two constitutive mutants of the transcriptional activator virG, virGN54D, and virGI106L, that support vir gene expression in a virA independent manner has previously been reported. Characterization of virGN54D by several groups showed considerable variation in its ability to activate vir gene transcription. In this study we demonstrate that these differences can be accounted for by plasmid copy number. We report the isolation of a third constitutive mutation, virGI77V, that partially restores transcription activation function of a nonfunctional virG mutant, virGD52E. The second regulator, VirA, in its extreme C-terminus, contains a domain that is homologous to the N-terminal domain of VirG. Deletion of this domain of VirA leads to a fully constitutive phenotype.