A L-histidine producing mutant was derived from Corynebacterium glutamicum HZ4221(TRA R DCP R AMT R histidase - )by means of mutagenesis with N-methy-N′-nitro- N-nitrosoguanidine(NTG).Contrast to original strain,the amount of histidine accumulation reached to a level of 5.31g/L in a medium containing 80g/Lglucose and 30g/L ammonium sulfate after cultured for 72 hours; the transketolase activity reduced to a degree of 15.7%.The utilization of the carbon sources,genetic stability,effect of metal ions were also been investigated in this paper.

Objective To explore the effect of vascular endothelial growth factor-C (VEGF-C) gene transfection on the expression level of VEGF-C in human breast cancer MCF-7 cell. Methods The constructed VEGF-C gene eukaryotic expression vector was transfected into the human breast cancer MCF-7 cell by using lipofectamine transfection reagents, and the positive cell clones were obtained through G418 selection after transfection. The expressions of VEGF-C mRNA and protein were detected by RT-PCR and Western blot respectively. Results Following the transfection of the VEGF-C recombination plasmid, there were significant differences on the expression levels of VEGF-C mRNA and protein between pcDNA3.1-VEGF-C transfection group and pcDNA3.1 transfection group (12.382?2.183 vs 6.039?1.950, P

Objective To investigate the expression of Toll-like receptor 4 (TLR4) of peripheral blood mononuclear cell (PBMC) in the different prognosis of patients with severe sepsis and its relation with endotoxin-tolerant.Methods Thirty-five patients with severe sepsis (severe sepsis group) and 15 healthy volunteers (control group),respectively stayed in ICU 24 h and physical examination in the day measured TLR4 expression of PBMC by flow cytometry and measured the serum of tumor necrosis factor (TNF)-α and interleukin (IL)-10 by enzyme-linked immunosorbentassay.Simultaneous separation of peripheral blood of PBMC,addition of 40 μ g/ml lipopolysaccharide (LPS) cultured for 24 h,and TLR4 expression of PBMC was measured in the same manner and the culture supernatant of TNF-α and IL-10.Results Thirty-five patients with severe sepsis survivor 25 cases (survivor group) and death 10 cases (death group),28 d death rate was 28.6％ (10/35).The TLR4 expression of PBMC in severe sepsis group was significantly lower than that in control group [(11.09 ± 8.90) MFI vs.(33.72 ± 12.59) MFI,P ＜ 0.01],the serum TNF-α and IL-10 in severe sepsis group were significantly higher than those in control group [(96.66 ± 45.33) ng/L vs.(2.53 ± 1.21) ng/L,(149.79 ± 67.15) ng/L vs.(34.56 ± 19.08) ng/L,P ＜ 0.01].There was no significant difference in TLR4 expression of PBMC between survivor group and death group (P ＞ 0.05).The TLR4 expression of PBMC in control group after LPS stimulation was significantly higher than that before LPS stimulation [(50.22 ± 19.23) MFI vs.(33.72 ± 12.59) MFI,P ＜ 0.05],survivor group and death group after LPS stimulation were significantly lower than those before LPS stimulation [(4.55 ± 2.30) MFI vs.(11.21 ±7.92) M FI and (5.46 ± 3.44) M FI vs.(10.15 ± 9.70) MFI,P ＜ 0.01].The culture supernatant of TNF-α,IL-10 in survivor group and death group were significantly lower than those in control group [(22.34 ± 8.27)and (19.49 ±5.35) ng/L vs.(88.70 ±34.21) ng/L,(54.29 ±32.89) and (98.04 ±40.26) ng/L vs.(146.56 ± 52.18) ng/L,P ＜ 0.01],but the culture supernatant of IL-10 in death group was significantly higher than that in survivor group (P ＜ 0.05).Conclusion Different prognosis of patients with severe sepsis have endotoxin tolerance and different inflammatory cytokine secretion abifity.

Objective To provide imaging anatomy basis for percutaneous nephrolithotomy ( PCNL) by measuring relative displacement and changes in anatomical position of kidney and colon under the prone and low-oblique supine positions.Methods Forty-six patients scheduled for PCNL underwent 64-slice spiral CT scan under the prone and low-arch oblique supine position before the PCNL.The horizontal distance of kidney and colon,the distance from colon and analog puncturing line,the distance between the kidney and colon were measured and compared between the 2 positions.Results The distance from colon and analog puncturing line under the low-oblique supine and prone positions were as follows,the left (26.56 ±15.36) mm versus (12.25 ±13.16) mm (t=3.527,P<0.05),the right (25.85 ±14.26) mm versus (13.57 ± 12.53) mm (t=3.234,P<0.05).The differences of the rest distances between the 2 positions were not significant ( P>0.05).Conclusions The distance between colon and analog puncturing line increases in the low-arch oblique supine position,because the colon shifts to the ventral.The PCNL in low-arch oblique supine position may reduce the incidence of colon injury,and improve surgical safety.

Endoscopy ; Humans ; Skull Base ; anatomy & histology ; surgery

Objective:To study the characteristics of high school students' coping styles when they faced frustrations and troubles,and the relationship between coping style and academic achievement.Methods:649 high school students completed questionnaire about middle school students' coping styles.Results:Girls were more inclined to use venting(2.7?0.7/2.4?0.7,F=23.32,P

In this paper, metabolic networks of the Corynebacterium glutamicum GWY020 and the two de-rivatives carrying additional mutations HUI821and GUI089 were established and modified. The concentra-tions of extra-cellular metabolites were determined under sub-steady-state (50 h~52 h) of the batch culture. The metabolic flux distribution maps of the three strains were obtained, compared and analyzed. These re-sults indicate that the introduction of analog supersensitive marker or analog resistant marker skew the metabolic flux towards the formation of L-Arginine. This study revealed the usefulness of the metabolic flux analysis as a tool for verification of existing production strains. The analysis may play an important role in helping us to rationally re-design metabolism for further improvement of fermentation process.

Microbial is a renewable resource which can produce polysaccharide. Its unique physiological activities and broad applications are attracting increasing attention. In this article, the source and the fermenta- tion conditions of microbial polysaccharide was reviewed, with a view to provide a scientific basis for the production of the microbial polysaccharide.

Objective To explore imaging features of Zinner syndrome.Methods Eight male patients with clinically diagnosed Zinner syndrome performed abdominal and pelvic CT and /or MRI scan.The radiological data was studied retrospectively.Results Eight cases showed seminal vesicle cyst with ipsilateral renal agenesis on CT and/or MR imaging ( left side, n =5; right side, n =3).The maximal diameter of seminal vesicle cysts varied from 4.2 to 7.0 cm, and appeared as oval cystic lesion with irregular contour or tube-like dilatation , which appeared low density on CT image and hypo-or hyperintensity on T 1 WI and hyperintensity on T 2 WI.Bladder compression was found in 6 cases.Fuild-fuild level in the cysts was seen in 2 cases.Remnants of ureter structure were seen in only 1 case.There was no other accompanying abnormality of urinary system.Conclusions Zinner syndrome presents with characteristic imaging features , and the key issue is differential diagnosis of seminal vesicle cysts.

BACKGROUND:Col agen type II and proteoglycan loss are two most obvious manifestations of cartilage damage in the onset of osteoarthritis. Changes in col agen type II and proteoglycan as the main components of cartilage matrix directly lead to cartilage degeneration and subsequently result in osteoarthritis. How to reverse or prevent the development of this process becomes the focus of medical research. OBJECTIVE:To observe the effect of warming yang and benefiting marrow recipe on the expression of col agen type II and proteoglycan in the articular cartilage of knee osteoarthritis rabbits as wel as to further explore the mechanism underlying chondrocyte protection. METHODS:Ninety-six New Zealand rabbits, aged 9 months old, male and female, were selected to prepare osteoarthritis models in extension position using cast immobilization method, and were randomly divided into four groups:blank group (untreated), model group (simple modeling), Chinese medicine group (intragastric administration of extracts of warming yang and benefiting marrow recipe, 24 mL/kg/d) and western medicine group (intragastric administration of glucosamine hydrochloride, 24 mL/kg/d). Intragastric administration was done once a day for 6 weeks. RT-PCR technology was used to observe the effect of warming yang and benefiting marrow recipe on the expression of col agen type II and proteoglycans in the articular cartilage, and pathological examination was also done. RESULTS AND CONCLUSION:The cartilage surface was smooth in the blank group and Chinese medicine group, with uniform toluidine blue staining, but in the model group and western medicine group, the cartilage surface was rough and the toluidine blue staining was extremely uneven with obvious loss of surface and middle layer dying. The expressions of cartilage proteoglycan and col agen type II in the model group were significantly lower than those in the blank group (P<0.01) as wel as in the Chinese medicine group and western medicine group (P<0.05). In addition, the expressions of cartilage proteoglycan and col agen type II in the Chinese medicine group were higher than those in the western medicine group (P<0.05). These findings indicate that the recipe of warming yang and benefiting marrow can enhance the expressions of col agen type II and proteoglycan, which can maintain the normal col agen phenotype and protect the articular cartilage.