Probing Methionine Uptake in Live Cells by Deuterium Labeling and Stimulated Raman Scattering.

The small biomolecule methionine (Met) is a fundamental amino acid required for a vast range of biological processes such as protein synthesis, cancer metabolism, and epigenetics. However, it is still difficult to visualize the subcellular distribution of small biomolecules including Met in a minimally invasive manner. Here, we demonstrate stimulated Raman scattering (SRS) imaging of cellular uptake of deuterated methionine (d8-Met) in live HeLa cells by way of comparison to the previously used alkyne-labeled Met analogue─homopropargylglycine (Hpg). We show that the solutions of d8-Met and Hpg have similar SRS signal intensities. Furthermore, by careful image analysis with background subtraction, we succeed in the SRS imaging of cellular uptake of d8-Met with a much greater signal intensity than Hpg, possibly reflecting the increased and minimally invasive uptake kinetics of d8-Met compared with Hpg. We anticipate that d8-Met and other deuterated biomolecules will be useful for investigating metabolic processes with subcellular resolution.

Factors predicting contralateral hematoma growth after unilateral drainage of bilateral chronic subdural hematoma.

OBJECTIVE Chronic subdural hematoma (CSDH) is a common form of intracranial hemorrhage with a recurrence rate of 9.2%-26.5% after bur hole surgery. Occasionally patients with bilateral CSDH undergo unilateral surgery because the contralateral hematoma is deemed to be asymptomatic, and in some of these patients the contralateral hematoma may subsequently enlarge, requiring additional surgery. The authors investigated the factors related to the growth of these hematomas. METHODS Ninety-three patients with bilateral CSDH who underwent unilateral bur hole surgery at Aizu Chuo Hospital were included in a retrospective analysis. Findings on preoperative MRI, preoperative thickness of the drained hematoma, and the influence of antiplatelet or anticoagulant drugs were considered and evaluated in univariate and multivariate analyses. RESULTS The overall growth rate was 19% (18 of 93 hematomas), and a significantly greater percentage of the hematomas that were iso- or hypointense on preoperative T1-weighted imaging showed growth compared with other hematomas (35.4% vs 2.3%, p < 0.001). Multivariate logistic regression analysis showed that findings on preoperative T1-weighted MRI were the sole significant predictor of hematoma growth, and other factors such as antiplatelet or anticoagulant drug use, patient age, patient sex, thickness of the treated hematoma, and T2-weighted MRI findings were not significantly related to hematoma growth. The adjusted odds ratio for hematoma growth in the T1 isointense/hypointense group relative to the T1 hyperintense group was 25.12 (95% CI 3.89-51.58, p < 0.01). CONCLUSIONS The findings of preoperative MRI, namely T1-weighted sequences, may be useful in predicting the growth of hematomas that did not undergo bur hole surgery in patients with bilateral CSDH.

Pial Arteriovenous Fistula Caused by Trauma: A Case Report.

We report an extremely rare case of pial arteriovenous fistula (AVF) caused by trauma. A 61-year-old man suffered from brain contusion by a traffic accident. He was neurologically normal on admission. However, his headache gradually worsened, and partial seizures occurred thereafter. He presented with general tonic seizure 7 days after the head injury. Magnetic resonance imaging demonstrated the exacerbation of brain edema and an abnormal vein near the contusion. Subsequent angiography showed a pial AVF, which was considered to be responsible for the brain edema. After treatment of the AVF by direct surgery, the brain edema was ameliorated. We should take into consideration the formation of vascular disease in cases with unexpected worsening of edema after brain injury.

Evaluation of new automated syphilis test reagents 'IMMUNOTICLES AUTO3' series: performance, biochemical reactivity, and clinical significance.

BACKGROUND: Automated nontreponemal and treponemal test reagents based on the latex agglutination method (immunoticles auto3 RPR: ITA3RPR and immunoticles auto3 TP: ITA3TP) have been developed to improve the issues of conventional manual methods such as their subjectivity, a massive amount of assays, and so on. We evaluated these reagents in regards to their performance, reactivity to antibody isotype, and their clinical significance. METHODS: ITA3RPR and ITA3TP were measured using a clinical chemistry analyzer. Reactivity to antibody isotype was examined by gel filtration analysis. RESULTS: ITA3RPR and ITA3TP showed reactivity to both IgM- and IgG-class antibodies and detected early infections. ITA3RPR was verified to show a higher reactivity to IgM-class antibodies than the conventional methods. ITA3RPR correlated with VDRL in the high titer range, and measurement values decreased with treatment. ITA3RPR showed a negative result earlier after treatment than conventional methods. ITA3TP showed high specificity and did not give any false-negative reaction. Significant differences in the measurement values of ITA3RPR between the infective and previous group were verified. CONCLUSIONS: The double test of ITA3RPR and ITA3TP enables efficient and objective judgment for syphilis diagnosis and treatments, achieving clinical availability.

[Evaluation of the anti-TP antibody latex agglutination immunoassay in routine testing and a clinical viewpoint].

We evaluated TP-LAIA (anti-TP latex agglutination immunoassay) and compared the results with those obtained using Serological Tests for Syphilis (STS), namely Venereal Disease Research Laboratory (VDRL) method and Rapid Plasma Reagin (RPR) test. We also examined early-stage antibody reaction using rabbits infected with active pathogen, and analyzed early-stage syphilis patient serum with IgM class anti-TP antibody. Based on routine test results and case history reviews for possible syphilis infection, TP-LAIA showed high specificity, 0.64% false positive results in comparison with 13.5% by VDRL method. Sensitivity was also significantly higher than TP-Hemagglutination Assay(TPHA). In the examination of TP early-stage infection, the fastest positive antibody reaction was observed with TP-LAIA, indicating its significance in the diagnosis of early-stage syphilis. TP-LAIA was confirmed to give a reliable reaction with IgM class anti-TP antibody. TP-LAIA results coincided with VDRL method results in the decrease in anti-treponemal antibody titers following medical treatment, suggesting that TP-LAIA will be a valuable tool for monitoring the effect of medical treatments. We concluded that not only the high sensitivity and specificity of TP-LAIA assay and its suitability for automation make it an ideal screening test, but also the assay performs sufficiently and satisfactorily for its use in monitoring medical treatments.

An in vitro evaluation of the glycation potential of a natural disaccharide, trehalose.

BACKGROUND: Glucose, an osmotic agent generally used in continuous ambulatory peritoneal dialysis (CAPD) dialysate, has a critical characteristic of forming advanced glycation endproducts (AGEs). We undertook this study to investigate whether a possible osmotic agent, trehalose, formed fewer AGEs than glucose. METHODS: Hemoglobin (Hb), a counter-protein of AGE, was incubated in four kinds of medium; glucose-phosphate buffered saline (PBS), autoclaved glucose-PBS, trehalose-PBS, and autoclaved trehalose-PBS, for 3, 7, 14, and 30 days, respectively. Polymerization of the Hb molecule was detected by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and carboxymethylated Hb was detected by Western blotting, using specific mono-clonal antibody for carboxymethylated N-terminal valine-Hb (CMV-Hb). RESULTS: PBS containing glucose showed bands of polymerized Hb molecule, a phenomenon which was markedly exaggerated by autoclaving. Likely, PBS containing glucose showed the formation of CMV-Hb in the long incubation of 30 days, and PBS containing autoclaved glucose showed accelerated formation of CMV-Hb in an incubation as short as 3 days. By contrast, PBS containing trehalose showed much less increase in a band of 30 k Dalton and in CMV-Hb formation even in autoclaved medium. CONCLUSIONS: Our present in vitro study clearly showed the superior characteristic of trehalose to produce fewer AGEs. Based upon the results of this study, we propose that the application of trehalose should be considered for CAPD solution.