Single shot spatial and temporal coherence properties of the SLAC Linac Coherent Light Source in the hard x-ray regime

We measured the transverse and longitudinal coherence properties of the Linac Coherent Light Source (LCLS) at SLAC in the hard x-ray regime at 9 keV photon energy on a single shot basis. Speckle patterns recorded in the forward direction from colloidal nanoparticles yielded the transverse coherence properties of the focused LCLS beam. Speckle patterns from a gold nanopowder recorded with atomic resolution allowed us to measure the shot-to-shot variations of the spectral properties of the x-ray beam. The focused beam is in the transverse direction fully coherent with a mode number close to 1. The average number of longitudinal modes behind the Si(111) monochromator is about 14.5 and the average coherence time τ(c)=(2.0±1.0) fc. The data suggest a mean x-ray pulse duration of (29±14)  fs behind the monochromator for (100±14) fc electron pulses.

Acute kidney injury in Chinese patients with lupus nephritis: a large cohort study from a single center

OBJECTIVE

In this study we assess clinicopathologic characteristics, treatment and prognosis of acute kidney injury (AKI) in a large cohort of Chinese patients with lupus nephritis.

METHODS

The clinical, laboratory, renal histopathology, treatment and outcome data were retrospectively collected and compared between lupus nephritis patients with and without AKI. The impact of AKI on renal outcome was evaluated.

RESULTS

Among 322 patients with renal biopsy-proven lupus nephritis, 66 (20.5%) were identified as AKI. Male predominance was observed in patients with AKI (p < 0.001). In comparison with the non-AKI group, patients with AKI had significantly higher proportions of serositis (p < 0.001), neurologic disorder (p = 0.026), anemia (p < 0.001), thrombocytopenia (p = 0.013) and nephrotic syndrome (p = 0.011), but significant lower serum C3 (p < 0.001). The Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores, renal pathological activity indices and chronicity indices were significantly higher in the AKI group (p < 0.001 in all cases). Regarding outcome, the AKI group had a significantly poorer renal outcome compared with non-AKI group (p < 0.001). In the AKI group, patients with crescentic glomerulonephritis and thrombotic microangiopathy had the worst renal outcome. AKI was an independent risk factor for renal outcome (hazard ratio [HR] = 5.819, 95% confidence interval 2.411-14.044, p < 0.001).

CONCLUSIONS

AKI is common in lupus nephritis and is an independent risk factor for renal outcome.

Coherence properties of individual femtosecond pulses of an x-ray free-electron laser

Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in "diffract-and-destroy" mode. We determined a coherence length of 17  μm in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.

The relationship between health professionals' weight status and attitudes towards weight management: a systematic review

This systematic review aims to address the question of whether health professionals' weight status is associated with attitudes towards weight management. Twelve eligible studies were identified from a search of the Cochrane Library, Ovid MEDLINE, EMBASE, PsycINFO, CINAHL and three Chinese databases, which included 14 independent samples comprising a total of 10 043 respondents. Attitudes towards weight management were classified under eight attitude indicators. Quantitative synthesis of the findings of included studies showed that health professionals of normal weight were more likely to be more confident in their weight management practice, perceive fewer barriers to weight management and have more positive outcome expectations, have stronger role identity and more negative attitudes towards obese individuals than health professionals who were overweight or obese. However, there was no difference between overweight and non-overweight health professionals in their perceptions of the causes and outcomes of obesity. In addition, being female and having relevant knowledge and clinical experience of weight management appeared to predict positive attitudes towards obesity/obese patients and high self-efficacy in weight management, respectively. Future research should focus on prospectively theory-driven studies, and employ appropriately validated instruments and multivariate analyses to identify the relative contribution of weight status to attitudes towards weight management.

Arterial stiffness and asymptomatic intracranial large arterial stenosis and calcification in hypertensive chinese

BACKGROUND

Intracranial large artery disease (ICLAD), such as stenosis and calcification, is common in Chinese patients with stroke. However, little is known about ICLAD and its association with large arterial stiffness in hypertensive patients.

METHODS

We recruited 270 (mean age 61.0 years, 45.6% male) untreated hypertensive patients without stroke from a community in Shanghai, China. ICLAD was detected by computerized tomographic angiography (CTA). Carotid-femoral pulse wave velocity (cf-PWV), office, and 24-h ambulatory pulse pressure (PP) as well as ambulatory arterial stiffness index (AASI) were determined as the measures of arterial stiffness.

RESULTS

Among all participants, 26 (9.6%) had concurrent intracranial arterial stenosis and calcification, 11 (4.1%) stenosis only, and 71 (26.3%) calcifications only. After adjustment for age, mean arterial pressure, and other covariables, there was significant difference in cf-PWV (13.1 vs. 13.7 vs. 15.0 m/s; P = 0.0015) and 24-h PP (46.7 vs. 48.8 vs. 55.7 mm Hg; P = 0.0007) between patients with normal vessels (n = 162), with stenosis or calcification (n = 82), and with both lesions (n = 26). Multiple ordinal logistic regression analyses showed that both cf-PWV and 24-h PP were independently associated with ICLAD. Odds ratios (95% confidence interval (CI)) of ICLAD after multivariable and mutually adjustment were 1.51 (1.09-2.10) and 1.46 (1.06-2.01) for 1-s.d. increase in cf-PWV and 24-h PP, respectively. No significant association (P ≥ 0.10) with AASI or office PP was observed in multivariable analysis.

CONCLUSION

Increased arterial stiffness was independently associated with ICLAD. cf-PWV and 24-h PP might be useful in identifying those more likely to have ICLAD among hypertensive patients.

MOVAS-1 cell line: a new in vitro model of vascular calcification

Vascular calcification has severe clinical consequences in a number of diseases, including diabetes, atherosclerosis and end-stage renal disease. The in vitro calcification of primary mouse, human and bovine vascular smooth muscle cells (VSMCs) is commonly employed to examine the mechanisms of vascular calcification. However, to date, no published studies have utilised a murine cell line to investigate this process. In the present study, we aimed to determine whether the mouse VSMC line MOVAS-1 can calcify in vitro. We established that the calcification of MOVAS-1 cells can be induced in the presence of calcifying medium (containing β-glycerophosphate and ascorbic acid), as detected by Alizarin Red and von Kossa staining, and quantification of calcium deposition and alkaline phosphatase activity. We also showed that the time course of MOVAS-1 calcification is comparable to that of the primary murine aortic VSMCs, establishing the MOVAS-1 cells as a feasible and relevant model. Significant increases in the mRNA expression profile of key genes associated with vascular calcification (Ocn, Akp2 and PiT-1) were observed in MOVAS-1 cells cultured under calcifying conditions, with similar changes in expression in murine aortic VSMCs. Furthermore, a significant reduction in calcification was observed in MOVAS-1 cells following treatment with levamisole and etidronate, known inhibitors of calcification. In conclusion, we demonstrated that the MOVAS-1 line is a reliable, convenient and economical system in which to investigate vascular calcification in vitro, and will make a useful contribution to increasing our understanding of this pathological process.

Accumulation and role of compatible solutes in fast-growing Salinivibrio costicola subsp. yaniae

The moderately halophilic bacterium Salinivibrio costicola subsp. yaniae showed an extremely fast growth rate. Optimal growth was observed in artificial seawater containing 1.4 mol/L NaCl and in MM63 media containing 0.6 mol/L NaCl. We analyzed a variety of compatible solutes that had accumulated in this strain grown in the media. The supplementation effect of the compatible solutes glycine betaine, glutamate, and ectoine to the growth of S. costicola subsp. yaniae was examined. Glycine betaine and glutamate had no supplementation effect on the fast growth rate. Growth of salt-sensitive mutants MU1 and MU2, both of which were defective in the ability to synthesize ectoine, was not observed in MM63 medium in the presence of more than 1.0 mol/L NaCl. From these data, we conclude that ectoine was the predominant compatible solute synthesized in this bacterium that effected an extremely fast growth rate.

Growth suppression of human laryngeal squamous cell carcinoma by adenoviral-mediated interleukin-12

This study explored the inhibitory role of the adenoviral-mediated-interleukin (IL)-12 (Ad.mIL-12) gene in the growth of laryngeal squamous cell carcinoma (LSCC). Human epithelial type 2 (Hep-2) cells were transfected with Ad.mIL-12, and IL-12 gene expression of the cells was evaluated. The proliferation and apoptosis of Hep-2 cells in vitro were detected by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and flow cytometry. Experimental tumours in mice were injected intratumourally with the same recombinant adenoviruses and inhibition of tumour growth observed. Apoptosis in Hep-2 xenotransplants was detected using TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labelling) assay and transmission electron microscopy. The expression of IL-12 in Ad.mIL-12 transfected Hep-2 cells was significantly increased. In vitro, Ad.mIL-12 decreased the viability of and increased apoptosis in Hep-2 cells. Increased apoptosis was also seen in vivo. The mean weight and volume of tumours in Ad.mIL-12 treated mice were significantly lower than in the control group. It is concluded that Ad.mIL-12 can suppress LSCC growth and induce apoptosis.

Relevance of lower airway bacterial colonization, airway inflammation, and pulmonary function in the stable stage of chronic obstructive pulmonary disease

The objective of this investigation was to verify the hypothesis that the presence of lower airway bacterial colonization (LABC) can be a stimulating factor of airway inflammation, more frequent exacerbation, and impact on pulmonary function, independent of current tobacco smoking in the stable phase of chronic obstructive pulmonary disease (COPD). A total of 46 ex-smokers with moderate to severe COPD, 19 healthy non-smokers, and 17 ex-smokers without COPD were included in this study. Their sputum specimens were collected at the first baseline visit and at the second visit after a follow-up of one year. The samples were analyzed for bacterial growth by culture, and the levels of interleukin (IL)-6, IL-8, and tumor necrosis factor alpha (TNF-α) were measured by enzyme-linked immunosorbent assay (ELISA). The frequencies of exacerbations and pulmonary function were compared at visit 2. At visit 1, 37.0% (17/46) were found to have LABC with bacterial loads ≥10⁶ CFU/ml in their sputum specimens. Haemophilus influenzae was the predominant pathogenic organism isolated. IL-8, IL-6, and TNF-α in these patients' sputum were significantly higher than those without LABC (p < 0.05). It was the presence of LABC that contributed to the significantly elevated IL-8 and IL-6 at the 1-year period (p < 0.05). LABC was also associated with significantly increased frequencies of exacerbations and declined forced expiratory volume in 1 s (FEV₁) (p < 0.05). LABC was documented in a subpopulation of stable COPD patients; it may be responsible for the deterioration of pulmonary function of COPD patients by promoting airway inflammation and/or increased frequency of exacerbations independently of tobacco smoking.

Comprehensive analysis of an Antarctic bacterial community with the adaptability of growth at higher temperatures than those in Antarctica

To investigate the adaptability to higher temperatures of Antarctic microorganisms persisting in low temperature conditions for a long time, Antarctic lake samples were incubated in several selection media at 25 degrees C and 30 degrees C. The microorganisms did not grow at 30 degrees C; however, some of them grew at 25 degrees C, indicating that the bacteria in Antarctic have the ability to grow at a wide range of temperatures. Total DNA was extracted from these microorganisms and amplified using the bacteria-universal primers. The amplified fragments were cloned, and randomly selected 48 clones were sequenced. The sequenced clones showed high similarity to the alpha-subdivision of the Proteobacteria with specific affinity to the genus Agrobacterium, Caulobacter and Brevundimonas, the ss-subdivision of Proteobacteria with specific affinity to the genus Cupriavidus, and Bacillus of the phylum Firmicutes. These results showed the presence of universal genera, suggesting that the bacteria in the Antarctic lake were not specific to this environment.

A novel endophytic Huperzine A-producing fungus, Shiraia sp. Slf14, isolated from Huperzia serrata

AIMS

To characterize and identify a novel Huperzine A (HupA)-producing fungal strain Slf14 isolated from Huperzia serrata (Thunb. ex Murray) Trev. in China.

METHODS AND RESULTS

The isolation, identification and characterization of a novel endophytic fungus producing HupA specifically and consistently from the leaves of H. serrata were investigated. The fungus was identified as Shiraia sp. Slf14 by molecular and morphological methods. The HupA produced by this endophytic fungus was shown to be identical to authentic HupA analysed by thin layer chromatographic, High-performance liquid chromatography (HPLC), LC-MS, (1) H NMR and acetylcholinesterase (AChE) inhibition activity in vitro. The amount of HupA produced by Shiraia sp. Slf14 was quantified to be 327.8 μg l(-1) by HPLC, which was far higher than that of the reported endophytic fungi, Acremonium sp., Blastomyces sp. and Botrytis sp.

CONCLUSIONS

The production of HupA by endophyte Shiraia sp. Slf14 is an enigmatic observation. It would be interesting to further study the HupA production and regulation by the cultured endophyte in H. serrata and in axenic cultures.

SIGNIFICANCE AND IMPACT OF THE STUDY

Although the current accumulation of HupA by the endophyte is not very high, it could provide a promising alterative approach for large-scale production of HupA. However, further strain improvement and the fermentation process optimization are required to result in the consistent and dependable production.

The molecular characteristics of cefepime-susceptible Escherichia coli and Klebsiella spp. isolates with a positive β-lactamase screening test result but negative confirmation

A negative extended-spectrum β-lactamase (ESBL) phenotypic confirmation test result obtained after a positive ESBL screening test result but which was cefepime-susceptible (NCPSCS) using the Clinical and Laboratory Standards Institute (CLSI) methods has been observed among isolates of Escherichia coli and Klebsiella spp. in the antimicrobial surveillance program in Shanghai, China. Among isolates collected from Huashan Hospital in 2005, NCPSCS strains were observed in 2.5% of 433 E. coli isolates and in 1.2% of 562 Klebsiella spp. isolates. We then selected 11 E. coli isolates and seven Klebsiella spp. NCPSCS isolates. Transmission electron microscopy (TEM), SHV, plasmid-borne AmpC, and CTX-M type ESBL genes were detected by the polymerase chain reaction (PCR) method. We found that all except two K. pneumoniae strains of NCPSCS isolates producing ESBL and AmpC harbored a plasmid-borne CMY-2 or DHA-1 type AmpC enzyme. The majority of NCPSCS E. coli and K. pneumoniae strains from Shanghai harbor plasmid-borne AmpC enzyme, and we recommend that, when NCPSCS strains are identified, further work such as the PCR detection of ESBL genes is necessary to determine whether they will produce ESBLs. The ESBL-positive strains should be reported as resistant to cefepime according to the CLSI guidelines.