For engineering an efficient butanol-producing Escherichia coli strain, many efforts have been paid on the known genes or pathways based on current knowledge. However, many genes in the genome could also contribute to butanol production in an unexpected way. In this work, we used Tn5 transposon to construct a mutant library including 1 196 strains in a previously engineered butanol-producing E. coli strain. To screen the strains with improved titer of butanol production, we developed a high-throughput method for pyruvate detection based on dinitrophenylhydrazine reaction using 96-well microplate reader, because pyruvate is the precursor of butanol and its concentration is inversely correlated with butanol in the fermentation broth. Using this method, we successfully screened three mutants with increased butanol titer. The insertion sites of Tn5 transposon was in the ORFs of pykA, tdk, and cadC by inverse PCR and sequencing. These found genes would be efficient targets for further strain improvement. And the genome scanning strategy described here will be helpful for other microbial cell factory construction.
Butanols ; chemistry ; DNA Transposable Elements ; Escherichia coli ; metabolism ; Fermentation ; Gene Library ; Hydrazines ; Industrial Microbiology ; Mutagenesis ; Open Reading Frames ; Organisms, Genetically Modified ; Polymerase Chain Reaction ; Pyruvic Acid ; chemistry

Objective:To comprehend morphology changes of temporomandibular joint in adults with mandible deviation,and the correlation in these changes.Methods:The mesofault radiographs of temporomandibular joint were taken in 21 adult patients with mandible deviation.The data described morphology of temporomandibular joint were analysed.Results:In adult patients with mandible deviation,the condyle process of opposite side was anterior and inferior when compared with deflected side.The height of condyle process,the upper height of condyle process,the gradient of prosobevel of condyle process and the gradient of back bevel of glenoid fossa were augmented when compared to deflected side.The gradient of prosobevel of condyle process showed positive correlation to the prosoblank of joint and the deep of glenoid fossa,and the height of condyle process showed positive correlation to the upper height of condyle process in both sides.The gradient of back bevel of condyle process showed positive correlation to the gradient of back bevel of glenoid fossa in deflected side.The gradient of back bevel of condyle process showed negative correlation to the supper blank of joint and the height of articular tubercle in opposite side.Conclusion:There are some differences in morphology of both temporomandibular joint in adults with mandible deviation,and there is some correlation between these changes.

0 05). Conclusions Microendoscopy discectomy via laminoctomy has advantages of less trauma and quicker recovery.It is safe and effective in the treatment of lumbar disc heniation with limited spinal stenosis.

Aqueous two phase system(ATPS) provides a gentle, non-denaturing separation environment for proteins, enzymes. While high-speed countercurrent chromatography (HSCCC) is a liquid-liquid partition chromatography which uses centrifugal force to hold the stationary phase and facilities the mobile phase partitioning through the stationary phase, it can produce high separation efficiency with large sample loading capacity. However, the ordinary HSCCC apparatus (Type J ) fails to retention a satisfactory stationary phase of ATPS because of its high viscosity and low interfacial tension. Nevertheless, the later designed cross-axis planetary centrifuge system(X-CPC) can produce a greater lateral force field and enhances significantly the retention of the ATPS stationary phase. A review of the application of these CCC techniques with ATPS in the separation of proteins was given. Meanwhile, new techniques such as pH-peak focusing CCC and dye-ligand affinity CCC and some new CCC column design for improvement of separation efficiency and retention of ATPS stationary phase are introduced.

Objective To prospectively assess the diagnostic accuracy of MR inflow inversion recovery (IFIR) fast imaging employing steady-state acquisition (FIESTA) for detection of renal artery stenosis (RAS),as compared with renal artery CT angiography (CTA) performed as the reference standard.Methods Thirty patients [18 males,12 females; mean age (65.0±12.1) years] with arterial hypertension and suspected RAS were examined by 3.0-T 3D MR IFIR-FIESTA and renal artery CTA within a week.The IFIR-FIESTA image quality,the IFIR-FIESTA and CTA in display of second-order and third-order branches of renal artery were assessed by two experienced readers.The sensitivity,specificity,accuracy,and negative predictive value (NPV) of IFIR-FIESTA were calculated on artery-by-artery and patient-by-patient bases by the two readers.The inter-observer agreement between the two readers in determining the presence and grade of renal artery stenosis was assessed.Results The scores of qualification of IFIR-FIESTA image quality by reader A and B were (2.16±1.02) and (2.00 ± 0.14),there was no significant difference between them (Z=-0.037,P=0.971).IFIR-FIESTA and CTA in display of second-order and third-order branches of renal artery had no significant difference (x2 =0.298,P=0.585).In the assessment of all 64 main renal arteries by reader A,IFIR FIESTA on artery-by-artery basis had sensitivity,specificity,accuracy,and NPV of 100％,96％,97％,and 100％,respectively; the above parameters assessed by reader B were 100％,90％,93％,and 100％,respectively.There was excellent inter-observer agreement (Kappa=0.803) with the presence or absence of hemodynamically significant RAS.In the assessment of all 30 patients by reader A,IFIR-FIESTA on patient-by-patient basis had sensitivity,specificity,accuracy,and NPV of 100％,95％,97％,and 100％; the above parameters assessed by reader B were 100％,85％,90％,and 100％,respectively; there was good inter observer agreement (Kappa=0.724) with the presence or absence of hemodynamically significant RAS.Conclusions Compared with CTA,MR IFIR-FIESTA can excellently assess RAS without contrast material and radiation exposure,therefore,it can be used for screening of RAS,especially should be widely applied to elderly patients with arterial hypertension.

Animals ; Animals, Newborn ; Brain Edema ; prevention & control ; Hypoxia-Ischemia, Brain ; prevention & control ; Progesterone ; therapeutic use ; Rats ; Rats, Wistar

Objective The purpose of this study was to explore the efficacy of low level laser treatment (LLLT) combined with initial periodontal therapy in treating chronic periodontits.Methods Eighteen patients with chronic periodontitis were randomly treated in a spit-mouth design with combination of laser (808 nm,80 mW) treatment with scaling and root planing (experimental) or with scaling and root planing alone (contol) after OHI and supragingival cleaning.Clinical parameters of sulcus bleeding index (SBI),periodontal probing depth (PD) and clinical attachment loss (CAL) of both sides were recorded and gingival crevicular fluid samples were collected at baseline and 1,4,12 weeks after the treatment.GCF samples were analyzed for b-FGF,IL-1β,IL-8 level using ELISA assay.Results For the change of SBI and PD,only SBI in the experimental group experienced significant reduction (P＜0.05) at 1 week compared with baseline (P＜0.05),and the reduction in both groups were statistically significant (P＜0.05) at 4 weeks.The same situation occurred while both experimental groups made more significant difference (P＜0.01) at 12 weeks.The reduction of SBI was obvious in both groups when the PD was more than 6 mm.For CAL,the experimental group showed signs of improvement (P＜0.05) at 4 weeks; both groups indicated improvement (P＜0.05),while the experimental was more significant (P＜0.01) at 12 weeks.For the levels of b-FGF,it showed steady rise after treatment in experimental group,while it went up to the baseline after falling in control group.At 12 weeks,there were statistical significance of differences between two groups (P＜0.05).The changes of IL-1β and IL-8,in the experimental group showed better results than that in control group,while the difference between two groups was not significant (P＞0.05).Conclusion LLLI can accelerate the healing of periodontal tissue by reducing the SBI,decreasing the PD,improving the CAL and increasing levels of b-FGF in the GCF of the patients.

Objective To study the mechanism that glial cell line-derived neurotrophic factor (GDNF)promotes human glio-ma cells proliferation.Methods We divided glioma samples into two groups,including low-grade glioma group and high-grade glio-ma group,while cerebral contusion patients were treated as the control group,12 cases in each group.C6 glioma cell lines were di-vided into three groups,such as GDNF group,BSA(bovine serum albumin)group and control group.CCK-8 (cell counting kit-8) was used to detect the cell proliferation,while Western blot was used to detect the expression of AKT,p-AKT,β-catenin and p-β-catenin in each group.Results Comparing with the control group,the expression levels of AKT,p-AKT,β-catenin and p-β-catenin in glioma group had a significantly increased (P <0.05).Meanwhile,the high-grade gliomas group also had a significant increase in those more than low-grade gliomas group (P <0.05).CCK-8 test showed that the cell proliferation in GDNF group was significant-ly higher than the control group (P <0.05),and the expression levels of p-AKT,β-catenin and p-β-catenin proteins all had a signifi-cant increase (P <0.05).However,the expression level of AKT had no obvious difference.Conclusion GDNF might promote the proliferation of glioma cells by up-regulating the expression of p-AKT,β-catenin and p-β-catenin.

Cold-heat problem is one core of traditional Chinese medicine theory. This paper summarizes the experimental research related to the biological basis of cold-heat essence in cold-heat syndrome, cold-heat body constitution and cold-heat property of Chinese herbs. In view of the classical physiological and biochemical indices, gene expression, protein expression and metabolic differences, differences in cold-heat syndrome or cold-heat constitution are mainly based on neurotransmitter, thyroid function, sex hormone, cyclic nucleotide system, and energy metabolism relating to the corresponding gene and protein expression. Furthermore, this paper analyses the change of correlation indices that accompany with a dynamic development process of "constitution-syndrome-herbal intervention", implying that the research of biological basis of cold-heat essence has turned from single index to multiple indices, and from dispersion research to system research.

A case of mercury-induced Baboon syndrome is reported.A 31-year-old female presented with a 2-3 day history of pruritic symmetric erythematous papules on both axillas,popliteal fossa,buttocks and groins.The patient was exposed to a broken mercury thermometer two days before the onset of the eruption.Patch testing showed that the patient was sensitive to ammoniated mercury,mercury,mercuric chloride and mercurochrome.The mercury levels in serum and full blood reached the up limit of normal value three days after the onset,and gradually decreased over time.The patient was diagnosed with Baboon syn- drome caused by mercury according to the clinical manifestation and results from laboratory studies.