The efficient production of L-glutamate is dependent on the product's rapid efflux, hence researchers have recently concentrated on artificially modifying its transport system and cell membrane wall structure. Considering the unique composition and structure of the cell wall of Corynebacterium glutamicum, we investigated the effects of CmpLs on L-glutamate synthesis and transport in SCgGC7, a constitutive L-glutamate efflux strain. First, the knockout strains of CmpLs were constructed, and it was confirmed that the deletion of CmpL1 and CmpL4 significantly improved the performance of L-glutamate producers. Next, temperature-sensitive L-glutamate fermentation with the CmpL1 and CmpL4 knockout strains were carried out in 5 L bioreactors, where the knockout strains showcased temperature-sensitive characteristics and enhanced capacities for L-glutamate production under high temperatures. Notably, the CmpL1 knockout strain outperformed the control strain in terms of L-glutamate production, showing production and yield increases of 69.2% and 55.3%, respectively. Finally, the intracellular and extracellular metabolites collected at the end of the fermentation process were analyzed. The modification of CmpLs greatly improved the L-glutamate excretion and metabolic flux for both L-glutamate production and transport. Additionally, the CmpL1 knockout strain showed decreased accumulation of downstream metabolites of L-glutamate and intermediate metabolites of tricarboxylic acid (TCA) cycle, which were consistent with its high L-glutamate biosynthesis capacity. In addition to offering an ideal target for improving the stability and performance of the industrial strains for L-glutamate production, the functional complementarity and redundancy of CmpLs provide a novel target and method for improving the transport of other metabolites by modification of the cell membrane and cell wall structures in C. glutamicum.
Corynebacterium glutamicum/genetics* ; Glutamic Acid/biosynthesis* ; Fermentation ; Metabolic Engineering ; Bacterial Proteins/metabolism* ; Bioreactors/microbiology* ; Gene Knockout Techniques

Objective: To observe the clinical efficacy of electroacupuncture (EA) in controlling myopia in children and its effect on retinal blood flow. Methods: Sixty-eight myopic children were randomly divided into an observation group and a control group, with 34 cases in each group. The control group was given auricular acupressure treatment alone, and the observation group was treated with EA once a week in addition to the treatment used in the control group. The spherical equivalent refraction (SER) and axial length (AL) were measured at baseline, and after 3 months and 6 months of treatment. Optical coherence tomography angiography was used to measure the vessel density (VD) and perfusion density (PD) in the surface layer of the retina. Results: After 3 months and 6 months of treatment, the changes in SER between the two groups were not statistically significant (P>0.05). After 3 months of treatment, the changes in AL between the two groups were not statistically significant (P>0.05); after 6 months of treatment, the change amount of AL in the observation group was smaller than that in the control group (P<0.05); after 3 months and 6 months of treatment, the changes in VD and PD in the surface layer of the retina in the observation group were significantly greater than those in the control group (P<0.01). Conclusion: EA treatment once a week for 6 months can delay the increase of AL and improve the retinal surface blood flow in myopic children.

In the study of oral orthodontics, the dental tissue models play an important role in finite element analysis results. Currently, the commonly used alveolar bone models mainly have two kinds: the uniform and the non-uniform models. The material of the uniform model was defined with the whole alveolar bone, and each mesh element has a uniform mechanical property. While the material of the elements in non-uniform model was differently determined by the Hounsfield unit (HU) value of computed tomography (CT) images where the element was located. To investigate the effects of different alveolar bone models on the biomechanical responses of periodontal ligament (PDL), a clinical patient was chosen as the research object, his mandibular canine, PDL and two kinds of alveolar bone models were constructed, and intrusive force of 1 N and moment of 2 Nmm were exerted on the canine along its root direction, respectively, which were used to analyze the hydrostatic stress and the maximal logarithmic principal strain of PDL under different loads. Research results indicated that the mechanical responses of PDL had been affected by alveolar bone models, no matter the canine translation or rotation. Compared to the uniform model, if the alveolar bone was defined as the non-uniform model, the maximal stress and strain of PDL were decreased by 13.13% and 35.57%, respectively, when the canine translation along its root direction; while the maximal stress and strain of PDL were decreased by 19.55% and 35.64%, respectively, when the canine rotation along its root direction. The uniform alveolar bone model will induce orthodontists to choose a smaller orthodontic force. The non-uniform alveolar bone model can better reflect the differences of bone characteristics in the real alveolar bone, and more conducive to obtain accurate analysis results.
Biomechanical Phenomena ; Computer Simulation ; Finite Element Analysis ; Humans ; Models, Biological ; Periodontal Ligament ; Stress, Mechanical ; Tooth Movement Techniques

assess clinical features and treatment outcomes in immunocompetent patients with primary central nervous system lymphoma (PCNSL). Methods Sixty?two patients with PCNSL who attended Guangdong General Hospital between January 1998 and January 2012 were included. Survival curves were estimated using Kaplan?Meier survival methodology and statistical significance of continuous was assessed via the Cox proportional hazard model. Results The median age of the patient cohort was 56 years, and the male to female ratio was 1.14∶1.00. The common presentations were increased intracranial pressure symptoms and neuron damage. Performance status of 54 (54/62, 87.1%) patients were the international prognostic index (IPI) 0-2. Diffuse large B?cell lymphoma (57/62, 91.9%) was most common, and the rest were T?cell lymphoma (4/62, 6.4%) and extranodal marginal zone lymphoma of mucosa?associated lymphoid tissue (1/62, 1.6%). In the series, 32 patients (32/62, 51.6%) had multiple lesions. Involvement of deep structures was found in 30 (30/62, 48.4%) patients. An elevated serum LDH level was detected in 19 (19/62, 30.6%) patients and the Ki?67 index was ≥90% in 38 (38/62, 61.3%) patients. Univariate analysis showed patients who were female, age<60 years, had WHO Eastern Cooperative Oncology Group performance status grade 0-2, single lesion, absence of deep structures involvement and normal LDH level showed better 2?year survival rate and longer median survival time. Significance was only seen in the normal LDH level group. Multivariate Cox regression analysis revealed that radical surgery only and Rituximab+ high?dose of methotrexate+ whole brain radiation therapy (WBRT) were independent prognostic indicators in PCNSL patients (P<0.05). Conclusions PCNSL is a rare but aggressive tumor with poor prognosis. Patients treated with high?dose of methotrexate combining with rituximab, followed by WBRT have a better prognosis and longer survival time, and thus these could probably be a promising treatment.

Objective: To assess clinical features and treatment outcomes in immunocompetent patients with primary central nervous system lymphoma (PCNSL). Methods: Sixty-two patients with PCNSL who attended Guangdong General Hospital between January 1998 and January 2012 were included. Survival curves were estimated using Kaplan-Meier survival methodology and statistical significance of continuous was assessed via the Cox proportional hazard model. Results: The median age of the patient cohort was 56 years, and the male to female ratio was 1.14∶1.00. The common presentations were increased intracranial pressure symptoms and neuron damage. Performance status of 54 (54/62, 87.1%) patients were the international prognostic index (IPI) 0-2. Diffuse large B-cell lymphoma (57/62, 91.9%) was most common, and the rest were T-cell lymphoma (4/62,6.4%) and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (1/62, 1.6%). In the series, 32 patients (32/62, 51.6%) had multiple lesions. Involvement of deep structures was found in 30 (30/62, 48.4%) patients. An elevated serum LDH level was detected in 19 (19/62, 30.6%) patients and the Ki-67 index was ≥90% in 38 (38/62, 61.3%) patients. Univariate analysis showed patients who were female, age<60 years, had WHO Eastern Cooperative Oncology Group performance status grade 0-2, single lesion, absence of deep structures involvement and normal LDH level showed better 2-year survival rate and longer median survival time. Significance was only seen in the normal LDH level group. Multivariate Cox regression analysis revealed that radical surgery only and Rituximab+ high-dose of methotrexate+ whole brain radiation therapy (WBRT) were independent prognostic indicators in PCNSL patients (P<0.05). Conclusions PCNSL is a rare but aggressive tumor with poor prognosis. Patients treated with high-dose of methotrexate combining with rituximab, followed by WBRT have a better prognosis and longer survival time, and thus these could probably be a promising treatment.

Mandible is an important bone of the head and neck. Mandibular defects not only affect patient's face, but also impede patient's daily functions, such as chewing, speech, and so on. Fibular transplantation for mandibular reconstruction is the common method, which requests high accuracy of bone positioning and posture adjustment. Therefore, a robotic system for mandibular reconstruction surgery with fibula flaps was designed to assist surgeons to hold and locate bones, and the model comparison experiments were conducted. The results showed that the robotic system can assist surgeons for mandibular reconstruction to improve quality of surgery.
Bone Transplantation ; methods ; standards ; Fibula ; transplantation ; Humans ; Mandible ; surgery ; Mandibular Reconstruction ; methods ; Robotics ; standards ; Surgery, Computer-Assisted

Objective To study the effect and mechanisms of TW-37 on cell proliferation,apoptosis,invasion and angiogenesis in pancreatic cancer cells in vitro and further explore the potential mechanism.Methods BxPC3 and HPAC cells were pretreated with TW-37 using untransfected or transfected with NF-κB p65 cDNA(p65 cDNA)or NF-κB p65 siRNA(siRNA-p65)cells as controls.Cell viability was determined by MrTT assay.Cell apoptosis was assessed by enzyme-linked immunosorbent assay (ELISA).Cell invasion and angiogenesis was detected by Transwell and endothelial tube formation assay of HUVECs.ELISA assay was used to measure the activity of NF-κB,and its target proteins of MMP-9 and VEGF were detected by western blot.Results TW-37 suppressed cell growth and induced apoptosis (A405:1.29 ± 0.21 vs 0.09 ± 0.01,1.07 s0.18 vs 0.08 ± 0.01),inhibited NF-κB activity and protein expression of NF-κB p65,VEGF and MMP-9(all P ＜0.05)in a dose-and time-dependent manner.The number of cells that invaded across the matrigel in the transwell chamber was (46.7 ±5.24) and (10.3 ± 1.26)/×200 in BxPC3 control and 0.75 μmol/L TW-37 group (P=0.001).The number of tube formation was (39.4 ±4.36) and (7.84 ± 1.25)/×200,(P =0.001).NF-κB activity was increased by p65 cDNA transfection,and decreased by TW-37 treatment in both of the two cell lines (P ＜0.05).However,NF-κB activity was decreased by p65 siRNA transfection,and greatly decreased by TW-37 treatment in both two cell lines (P ＜0.05 or P ＜0.01).Transfection of p65 cDNA did not significantly affect cell apoptosis.Transfection of p65 siRNA increased cell apoptosis,and greatly increased by TW-37 treatment in both two cell lines (all P ＜ 0.01).Conclusions TW-37 could inhibit the proliferation,invasion and angiogenesis in pancreatic cancer cells by regulating NF-κB signal pathway.

BACKGROUNDIn recent years, computers have been intensively used at home. In contrast to paper-based books and documents, computer screen is self-illuminated with larger screen-background luminance difference, which greatly induces visual discomfort. To compensate for that, one effective solution is to offer an additional background luminance. In this study, we investigated whether and to what extent additional background lighting is needed in looking at a computer display comfortably.

METHODSIn this study, 60 healthy children aged from 9 to 12 years and 58 adults aged from 21 to 39 years participated in the experiments. They were asked to choose their most preferred background luminance intensities at three screen luminance levels. The data were analyzed by Matlab (R2012b) and SPSS 20.0.

RESULTSBoth children and adult participants selected a non-dark background as their comfortable lighting condition when watching a computer display (children: t (59) = 22.0, P < 0.01, adults: t (57) = 15.5, P < 0.01). Comparatively, children preferred brighter background in general ( F (1,116) = 7.0, P < 0.01). More importantly, participants' preferred background luminance levels were linearly correlated with screen luminance intensities (children: slope = 0.97, R(2) = 0.98; adults: slope = 0.38, R(2) = 1.00).

CONCLUSIONThese results indicate that varying background luminance to maintain screen-background luminance ratio is beneficial to human visual comfort.

Adult ; Child ; Computers ; Contrast Sensitivity ; physiology ; Female ; Humans ; Lighting ; Male ; Myopia ; prevention & control ; Young Adult

Objective To observe curative effect of olopatadine in treatment of allergic conjunctivitis combined with frequently winking in children. Design Prospective case series. Participants Ninety seven children with frequently winking aged 3-12 years in Shanghai Eye and ENT Hospital. Methods According to the factor in causation of frequently winking (FW), 97 children were divided into allergic conjunctivitis (AC) group, trichiasis combined AC group, AC with tics group, trichiasis group, tics group and unknown cau-sation group after clinical examination. The first 3 groups with AC were treated with olopatadine 0.1% ophthalmic solution b.I.d.(n=35) and emedastine 0.05% ophthalmic solution was used q.I.d, in AC group as control(n=32). The patients were followed after 3 weeks and the extent of symptoms of FW was recorded. Main Outcome Measures Extent of the symptoms of FW. Result The effective rate of olopatadine in treating FW caused by AC or AC combined with other diseases was 80.43%. The effective rate in FW children caused mainly by AC was 82.86% which was higher than that of control drug emedastine (75.0%) (P=0.02). Seven cure cases were all in olopatadine treating group. Conclusion AC is the most common and main causative factor in FW children. Early use of olopatadine ophthalmic drop can effectively alleviate FW symptoms. (Ophthalmol CHN, 2009, 18: 272-274)

OBJECTIVE To evaluate the reason and protection measures of occupational exposure.METHODS From Jan 2005-Mar 2008,all medical personnel in our hospital were investigated by face to face investigation and checking recording data.The causes,modalities,management and prophylaxis of occupational exposure were analyzed.RESULTS Seventy-six person suffered occupational exposure,including 51 nurses(67.11%),18 doctors(23.68%) and the other 7 workers.Occupational exposure mainly occurred in 20-30 years old medical workers.61 persons(80.26%) suffered stab injury and sharp instrument injury.All 76 front medical personnel could make appropriate management after occupational exposure and without further infection.CONCLUSIONS Some first front medical personnel do not recognize the hazard of the occupational exposure.It′s necessary to enhance the management and training and to establish a corresponding standard to protect medical personnel from being harmed by occupational exposure.