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The aim of this study is to reveal the interaction relationships between lauryl dimethylamine N-oxide (LDAO) and peripheral light-harvesting complex (LH2) as well as the influence of LDAO on structure and function of LH2. In the present work, the effects of LDAO on the conformation and release processes of bacteriochlorophyll (BChl) of LH2 when incubated under different temperature and pH in the presence and absence of LDAO were investigated by spectroscopy. The results indicated that (1) the presence of LDAO resulted in alterations in the conformation, alpha-helix content, and spectra of Tyr and B850 band of LH2 at room temperature and pH 8.0. Moreover, energy transfer efficiency of LH2 was enhanced markedly in the presence of LDAO. (2) At 60 degrees C, both the B800 and B850 band of LH2 were released and transited into free BChl at pH 8.0. However, the release rates of bacteriochlorophylls of B800 and B850 band from LH2 were slowed down and the release processes were changed when incubated in the presence of LDAO. Hence, the stability of LH2 was improved in the presence of LDAO. (3) The accelerated release processes of bacteriochlorophylls of B800 and B850 band of LH2 were induced to transform into bacteriopheophytin (BPhe) and free BChl by LDAO in strong acid and strong alkalic solution at room temperature. However, the kinetic patterns of the B800 and B850 band were remarkably different. The release and self-assemble processes of B850 in LH2 were observed in strong acid solution without LDAO. Therefore, the different release behaviors of B800 and B850 of LH2 are induced by LDAO under different extreme environmental conditions.

Background: Patients undergoing carotid endarterectomy for extracranial internal carotid artery stenosis are at risk of cerebral ischemia/hypoperfusion. Criterion recommended by European and American committees to determine whether to place a shunt consisted of a decline in transcranial Doppler ultrasonography-measured middle cerebral artery blood flow velocity (MCBFV) to < 30% to 40% of intraoperative preclamp value., Objective: To assess the discriminative power of the bispectral index (BIS)-Vista monitor for detecting a 40% decline in MCBFV with cross-clamping., Methods: In 20 patients undergoing carotid endarterectomy under remifentanil/propofol anesthesia, BIS-Vista data, MCBFV, and pulsatility index from bilaterally mounted BIS-Vista and transcranial Doppler monitors were continuously recorded., Results: Coefficient of determination revealed good correlation (r = 0.763) between ipsilateral BIS-Vista and MCBFV after cross-clamping. BIS-Vista exhibited a high discriminative power of 0.850 (95% confidence interval, 0.455-0.966) area under the receiver-operating characteristic curve in detecting an ipsilateral 40% MCBFV decline. Two-way analysis of variance (location by time) suggests that BIS-Vista exhibited a global decline; ie, both BIS-Vistas declined when 1 carotid on either side was clamped because there was no significant interhemispheric difference (P = .112) in mean BIS-Vista values over time., Conclusion: Although we demonstrated good correlation and high discriminative power of the BIS-Vista monitor in depicting a MCBFV decline that could serve as indicator of decline in cerebral activity, BIS-Vista cannot be considered a reliable indicator of cerebral ischemia/hypoperfusion that could replace transcranial Doppler monitoring to determine whether a shunt is to be placed.

As electrochemically active bacteria play an important role in microbial fuel cells (MFCs), it is necessary to get a comprehensive understanding of their electrogenesis mechanisms. In this study, a new electrochemically active bacterium, Klebsiella sp. ME17, was employed into an "H" typed MFC for electrogenesis, with glucose as the electron donor. The maximum power density was 1,209 mW/m2 at a resistance of 340 Omega and the maximum current was 1.47 mA. Given the original anode medium, fresh medium, and the supernatant of the anode medium in the same MFC, respectively, the polarization curves illustrated that the strain produced mediators to promote extracellular electron transfer. The anode medium supernatant was electrochemically active, based on cyclic voltammogram, and the supernatant was very likely to contain quinone-like substances, as indicated by spectrophotometric and excitation-emission matrix fluorescence spectroscopy analysis. Further investigation on the color and ultraviolet absorbance at 254 nm of the filtered anode medium showed that the redox states of mediators strongly associated with the electricity generation states in MFCs.

Crossoptilon mantchuricum (brown-eared pheasant) is an endemic to northern China and one of the state first-protection animals, which is now confined to scattered localities in Guandi Mountains, Guancen Mountains, Luliang Ranges of western Shanxi, and the mountains of north-western Hebei, western Beijing and central Shaanxi. Its range is fragmented by habitat loss because of human activity and other intervention, and isolated populations are resulting in facing the extinction risk from further forest destroyed and other pressures. The trace elements are very important to the growth and development of brown-eared pheasant, and these elements in the feather are closely correlated to the contents in the organs of the bird. By research on the elements contents in the feather, the authors are able to get more information about the growth, development, reproduction, immunity and metabolism function for this bird. The aim of this study is to try providing scientific basis for further enhancing the protection and the artificial breeding. Ten elements including Mo, Zn, Ni, Fe, Mn, Cr, Cu, K, Pb and Cd were determined in the feather of brown-eared pheasant by ICP and AAS, respectively. For the analysis two samples were from Luya Mountain Natural Reserve and Pangquangou Natural Reserve, and one was from Taiyuan Zoo, Shanxi. The contents of the elements in the feather of wild and captive brown-eared pheasants were compared each other. The results showed that the contents of the eight elements the feather from the Zoo were lower than those from Luya Mountain Natural Reserve and Pangquangou Natural Reserve. Moreover, Fe is the highest among those ten elements, Cd was not found, and Mo and Cr were much lower than the others. It is suggested that varying habitats have obvious effects on the elements contents of wild bird body, and wild habitant is more beneficial to the bird growth and development. Applying the results to wild animal management would be favorable to the protection, reproduction and expanding population of rare and endangered birds.

Background & Objective: Recently, vascular endothelial growth factor-C (VEGF-C) and -D (VEGF-D) have been identified as specific lymphangiogenic factors, and their overexpression are related to lymphatic metastasis. This study was to investigate the expression and clinical significance of VEGF-C and VEGF-D in nasopharyngeal carcinoma (NPC)., Methods: The expression of VEGF-C, VEGF-D, vascular endothelial growth factor receptor-3 (VEGFR-3), and CD34 in 66 specimens of NPC and 19 specimens of nasopharyngitis tissue were detected by SP immunohistochemistry. Lymphatic microvessel density (LMVD) and microvessel density (MVD) were calculated., Results: The high expression rate of VEGF-C was significantly higher in NPC than in nasopharyngitis tissues (54.5% vs. 26.3%, P<0.05). The high expression rate of VEGF-C was significantly higher in the NPC with regional lymph node metastasis than in those without, and higher in the NPC with high T stage than in those with low T stage (P<0.05). Both univariate and multivariate logistic regression analyses showed that high expression of VEGF-C was correlated to regional lymph node metastasis (P<0.05), but not to age, sex, 5-year survival, LMVD, and MVD (P>0.05). The positive rate of VEGF-D was significantly higher in NPC tissues than in adjacent non-cancerous tissues (69.7% vs. 42.1%, P<0.05). In NPC tissues, VEGF-D expression had no correlations to age, sex, T stage, regional lymph node metastasis, LMVD, and MVD (P>0.05), but was positively related to high expression of VEGF-C. The 5-year survival rate was significantly lower in VEGF-D-positive NPC than in VEGF-D-negative NPC (50.0% vs. 85.0%, P<0.05)., Conclusion: In NPC, high expression of VEGF-C is closely correlated to regional lymph node metastasis; positive expression of VEGF-D shows no correlation to regional lymph node metastasis, but is positively related to high expression of VEGF-C and closely correlated to 5-year survival rate.

Objective: To explore the accuracy and role of magnetic resonance imagine (MRI)-guided stereotactic biopsy for atypical diseases in brain., Methods: Using MRI volume scan and multiplane reconstruction, MRI-guided stereotactic brain biopsies were performed with CRW stereotactia frame in twenty-six patients whose lesions were atypical or unable to be detected by CT scanning., Results: No serious complication (intracranial hematoma, paralysis) caused by brain biopsy was found in all twenty-six patients. Definite pathologic diagnosis and appropriate treatment were given to these patients. The lesions included gliomatosis cerebri, brain cysticercosis and Krabbe's disease, et al., Conclusions: MRI-guided stereotactic brain biopsy is more accurate for pathological diagnosis than CT-guided stereotactic brain biopsy. MRI-guided stereotactic biopsy can provide reliable diagnosis and treatment especially for the questionable lesions in brain.

Effects of various factors on asymmetric synthesis of R-phenylaminoethanol from aminoacetophenone by the whole cells of Arachnia sp. P163 producing alcohol dehydrogenase for phenylethanol amine was investigated. It found that, although the reduction was inhibited by the substrate and the product, but it has the very high stereoselectivity. The reduction was normaly carried out with 2% glucose for reproduction of coenzyme in the reaction system without oxygen. The conversion yield and ee value of the product achieved 65% and 100%, respectively.

We present a case report of the first adult woman reported to suffer from both urethral obstruction and bilateral ureteral hydronephroses secondary to fecal impaction. The work-up suggested that hypothyroidism might be the cause for fecal impaction. Urinary tract obstruction caused by hypothyroidism-induced fecal impaction has never been reported. Fecal impaction should be considered as one of the causes for urinary tract obstruction.

Human immunodeficiency (HIV) infection often presents with an unusual symptom complex. Although cytomegalovirus (CMV) is a frequent opportunistic infection in the late stage of acquired immunodeficiency syndrome (AIDS), CMV pneumonitis as an initial manifestation of HIV infection is not documented in the medical literature. We report a previously healthy patient with bilateral interstitial pulmonary infiltrates who was found to have CMV pneumonitis; only later was HIV virus infection diagnosed. Cytomegalovirus is a frequently isolated pathogen from respiratory secretions in AIDS patients. The role of CMV as a sole pulmonary pathogen is controversial. After exclusion of other pathogens, CMV was demonstrated by histological changes and viral culture in our case. This case indicates that pulmonary infiltrates presenting as the first manifestation of HIV infection can be caused by CMV infection.

The authors report five patients who developed non-operative regions extradural hematoma following removal of intracranial tumors (3 cases) or cystiform diseases (2 cases). 3 cases developed on the left hemicerebrum. 2 cases formed on the bilateral. 4 cases were supratentorial operations, one inferior tentorial. The causative mechanisms of hematoma formation were attributed to a rapid fall in intracranial pressure, an increased blood velocity and the patient's position during the operation. Unexplained cerebral swelling during operation or delayed post-operative recovery should be intensely investigated by CT scanning. An emergency operation is indicated when the hematoma volume is more than 30ml.

The smooth-muscle cells of narrow segment in the ureter with congenital hydronephrosis in 5 cases were studied by transmission electron microscope. The result showed that the smooth-muscle cells of the narrow segment lack of myofilaments, dense body and dense patch in cells membrane. The above mentioned structures are functional deficient basis of the smooth-muscle cells in the ureter. Its deficiency results in the poor peristalsis function of the narrow segment of the ureter in congenital hydronephrosis. The cause and treatment principle in congenital hydronephrosis were discussed.