Mid-infrared Cr2+:ZnSe random powder lasers

We report simple methods of laser active Cr2+:ZnSe powder fabrication with average grain sizes of either approximately 10 or approximately 1 microm without crystal growth stage. Pure, uniformly mixed ZnSe and CrSe powders annealed at 1000 masculineC for 3 days in a sealed evacuated (approximately 10(-4) Torr) quartz ampoule exhibited middle-infrared laser action at room temperature under 1.56 microm excitation of D(2) Raman shifted radiation of Nd:YAG laser. The output-input characteristic clearly demonstrated the threshold-like behavior of the output signal with the threshold energy level of 0.5 and 3 mJ in 2.9 mm spot for 10 and 1 microm grain sizes, respectively.

Efficacy and safety of high concentration lidocaine for trigeminal nerve block in patients with trigeminal neuralgia

AIMS

Local anaesthetics, which act as neurolytics and Na(+) channel blockers, have been used for disrupting the neural firings in certain neuropathic pain conditions. This study was undertaken to investigate the clinical outcome of trigeminal nerve block with 10% lidocaine in the management of trigeminal neuralgia (TN).

METHODS

Thirty-five patients with primary TN received trigeminal nerve blocks with 10% lidocaine. Success was defined as complete pain relief or mild pain without medication 1 day after the treatment. We followed the patients up every 2 months assessing for pain recurrence, sensory changes and other complications for a total of 37-45 months (median 43 months).

RESULTS

Twelve of the 35 patients (34.3%) responded favourably to the treatment and were considered as success. Eleven patients experienced complete pain relief and one could tolerate pain without medication 1 day after the blocks, which lasted for 3-172 weeks. Four patients experienced mildly decreased sensation in the region of the face supplied by the nerve 1 day after the blocks; however, all recovered normal skin sensation in 6 months. There was neither allodynia nor other sensory discomfort. The pain intensity and current pain duration before treatment were significantly different between the two groups.

CONCLUSION

Trigeminal nerve block with high concentration lidocaine (10%) is capable of achieving an intermediate period of pain relief, particularly in patients with lower pain intensity and shorter pain duration prior to the procedure.

Effect of linear density of states on the quasiparticle dynamics and small electron-phonon coupling in graphite

We obtained the spectral function of very high quality natural graphite single crystals using angle-resolved photoelectron spectroscopy. A clear separation of nonbonding and bonding bands and asymmetric lineshape are observed. The asymmetric line shapes are well accounted for by the finite photoelectron escape depth and the band structure. The extracted width of the spectral function (inverse of the photohole life time) near the K point is, beyond the maximum phonon energy, approximately proportional to the energy as expected from the linear density of states near the Fermi energy. The upper bound for the electron-phonon coupling constant is about 0.2, a much smaller value than the previously reported one.

Low levels of serum cholesterol and albumin and the risk of community-acquired pneumonia in young soldiers

SETTING

The risk factors of community-acquired pneumonia (CAP) in high-risk groups have been examined in many studies. Such studies, however, have limited application for young people in special environments.

OBJECTIVE

To study the risk factors of CAP in young soldiers.

DESIGN

A hospital-based case-control study was carried out during the two winters between 2003 and 2005. A total of 255 CAP cases aged 18-23 years were enrolled and were matched by age and date of hospitalisation with 255 controls.

RESULTS

All CAP cases and 148 controls (58.0%) were military trainees. Most cases (96.1%) were non-severe CAP (pneumonia severity index risk class 1). Serum levels of total cholesterol, albumin, total protein and body mass index (BMI) were lower in CAP cases than in controls. In conditional logistic regression analysis, an increased risk of CAP was independently associated with military trainees, low levels of cholesterol and albumin. However, low BMI (<18.5 kg/m(2)) was not found to be associated with the risk of CAP after adjusting for other factors.

CONCLUSION

In Korea, the risk of CAP is significantly high in military trainees, with low levels of cholesterol and albumin being associated with the development of CAP in young soldiers.

Comparison of polymerase chain reaction methods for the detection of Theileria equi infection using whole blood compared with pre-extracted DNA samples as PCR templates

Rapid, efficient, and reproducible procedures for isolating DNA before PCR gene amplification are essential for the diagnosis of piroplasms. In this study, we evaluated the ease and reliability of detecting Theileria equi by PCR using pre-extracted DNA samples (by QIAamp DNA Mini Kit and phenol-chloroform methods) compared with blood spotted on FTA cards as PCR templates. Although minimal variations in limit of detection were observed among the methods compared, overall, the use of pre-extracted DNA samples and blood spotted on FTA cards had comparable detection limits. These results indicate that T. equi infection can be efficiently detected directly from FTA cards by PCR without the need for pre-extraction of DNA from blood samples.

Separase, securin and Rad21 in neural cell growth

The key mitotic regulator securin is expressed at low levels in fetal brain compared with adult, and modulates the proliferation of human embryonic neuronal N-Tera2 (NT2) cells. We now examine the function and expression of securin's interacting partner separase, along with Rad21, the functional component of cohesin, which is cleaved by separase following interaction with securin. In contrast to securin, the cleaved forms of separase and Rad21 were highly expressed in human fetal cerebral cortex compared with adult. In a murine model of absent securin expression - the PTTG knock-out mouse - separase and Rad21 were over-expressed in multiple brain regions. In addition, cDNA array analysis of other key mitotic regulators additionally identified cyclin C and sestrin 2 to be induced in the brains of securin-null mice compared with wild type. Further, Rad21 mRNA expression was highly correlated with that of securin, separase, cyclin C and sestrin 2 in fetal brains. In embryonic neuronal NT2 cells, siRNA repression of separase failed to significantly alter cell turnover, whereas repression of securin expression resulted in increased levels of the activated forms of Rad21 and separase, and promoted cell proliferation. Our data suggest that the co-ordinated expression of separase, securin and Rad21 is fundamental for the developing brain.

Regular oscillatory behavior of aqueous solutions of CuII salts related to effects on equilibrium dynamics of ortho/para hydrogen spin isomers of water

Cell surface and growth-related NADH oxidases with protein disulfide-thiol interchange activity, ECTO-NOX, exhibit copper-dependent, clock-related, temperature-independent and entrainable patterns of regular oscillations in the rate of oxidation of NAD(P)H as do aqueous solutions of copper salts. Because of time scale similarities, a basis for the oscillatory patterns in nuclear spin orientations of the hydrogen atoms of the copper-associated water was sought. Extended X-ray absorption fine structure (EXAFS) measurements at 9302 eV on pure water were periodic with a ca. 3.5 min peak to peak separation. Decomposition fits revealed 5 unequally spaced maxima similar to those observed previously for Cu(II)Cl(2) to generate a period length of about 18 min. With D(2)O, the period length was proportionately increased by 30% to 24 min. The redox potential of water and of D(2)O also oscillated with 18 and 24 min period lengths, respectively. Measurements in the middle infrared spectral region above a water sample surface revealed apparent oscillations in the two alternative orientations of the nuclear spins (ortho and para) of the hydrogen atoms of the water or D(2)O with 5 unequally spaced maxima and respective period lengths of 18 and 24 min. Thus, the time keeping oscillations of ECTO-NOX proteins appear to reflect the equilibrium dynamics of ortho-para hydrogen atom spin ratios of water where the presence of metal cations such as Cu(II) in solution determine period length.

Medical student radiology teaching in Australia and New Zealand

This study, involving 19 centres, establishes the status of medical student radiology teaching in Australia and New Zealand. It aims to document the academic and clinical staff profile involved in teaching, to indicate the methods of instructions used, to outline the available radiology library resources for medical students, to list the textbooks used in teaching and to uncover how many radiology departments are involving medical students in research. The findings can be used to plan and execute further actions that will enhance radiology teaching of medical students.

Benefit from adjuvant trastuzumab may not be confined to patients with IHC 3+ and/or FISH-positive tumors: Central testing results from NSABP B-31

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Background: Trastuzumab is a humanized monoclonal antibody targeted to HER2 protein and currently indicated for HER2-positive breast cancer defined by overexpression of HER2 protein (3+ IHC staining by HercepTest™) or HER2 gene amplification (HER2/CEP17 ratio over 2 by PathVysion® FISH assay). These criteria were determined for advanced disease but have not been formally tested in the adjuvant setting. We examined these tests’ ability to predict benefit from adjuvant trastuzumab in NSABP trial B-31. Methods: All available tumor tissue blocks from the B-31 trial were subjected to HercepTest and PathVysion assay as defined in the B-31 protocol. Formal statistical test of interaction between HER2 levels measured by these two tests and benefit from trastuzumab was performed. Results: 207 of 1,795 cases (11.5%) showed gene amplification as determined by PathVysion, and 255 of 1,662 (15.3 %) showed overexpression as determined by HercepTest. 161 of 1,662 (9.7%) had neither gene amplification nor overexpression. There was a consistent benefit from trastuzumab in every subset defined by IHC or FISH. No statistical interaction was found between DFS benefit from trastuzumab and levels of protein (p=0.26) or HER2 gene copy number (p=0.60). Benefit was observed in patients with tumors that were negative for FISH and had less than 3+ staining intensity on IHC by HercepTest (RR=0.36 [CI: 0.14–0.92] p=0.032). Conclusion: Current definition of HER2 overexpression/gene amplification based on data from advanced disease may need to be modified for the adjuvant setting.

[Table: see text]

No significant financial relationships to disclose.

18F-FDG uptake on positron emission tomography in gefitinib-treated non-small cell lung cancer patients

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Background: This study evaluated the clinical significance of 18F-fluoro-2-deoxy-glucose (FDG) uptake on positron emission tomography (PET) in gefitinib-treated non-small-cell lung cancer (NSCLC) patients. Method: We retrospectively analyzed PET scans of 66 NSCLC patients with stage IIIB-IV and its association with gefitinib responsiveness. Response rate and time-to- progression (TTP) were analyzed according to the maximum standardized uptake value (SUV) at presentation. Cut-off vale of SUV was obtained from receiver operating characteristic analysis. Univariate and multivariate analyses were performed. Results: According to smoking history and pathology, different response rates were observed (P = 0.012 and 0.048, respectively). Thirteen patients were categorized into low SUV group. Patients with low SUV showed higher RR compared with those with high SUV (46% vs 13%, P = 0.007). In univariate analysis, prolonged TTP was observed in never-smoker (P = 0.007). Low SUV was associated with prolonged TTP (P = 0.010). Multivariate analysis confirmed that low SUV and never-smoker remained favorable prognostic factors (P = 0.046 and 0.043, respectively). Conclusion: These results suggest that FDG uptake may be predictive of outcome in gefitinib-treated non-small-cell lung cancer patients.

No significant financial relationships to disclose.