Muscular Echo-Intensity of the Quadriceps by Ultrasound Is More Related to Improvement of Gait Independence than Muscle Thickness in Older Inpatients

OBJECTIVES

This study aimed to examine whether the decrease in muscular echo-intensity of the quadriceps by ultrasound in older inpatients is related to the improvement of gait independence than the increase of muscle thickness.

DESIGN

Longitudinal study.

SETTING

Hospital-based study.

PARTICIPANTS

This study included 171 inpatients aged ≥ 65 years (median age: 84.0 [77.0-88.0], 56.1% female). Patients who were able to walk independently at hospital admission were excluded from the study.

MEASUREMENTS

Improvement of gait independence during hospital stay was assessed using the change in Functional Independence Measure (FIM) gait score (i.e., FIM gait score at hospital discharge minus FIM gait score at hospital admission) and FIM gait score at hospital discharge. Muscular echo-intensity and muscle thickness of the quadriceps were assessed at hospital admission and discharge using ultrasound images, respectively. Muscular echo-intensity has been shown to be mainly related to intramuscular adipose tissue. Multiple linear regression analysis was performed to identify the factors independently associated with the change in FIM gait score and FIM gait score at discharge.

RESULTS

Change in quadriceps echo-intensity was independently and significantly associated with the change in FIM gait score (β = -0.22, p = 0.017) and FIM gait score at hospital discharge (β = -0.21, p = 0.017). In contrast, change in quadriceps thickness was not independently and significantly associated with the change in FIM gait score (β = 0.16, p = 0.050) and FIM gait score at hospital discharge (β = 0.15, p = 0.050).

CONCLUSIONS

Our study indicates that a decrease in muscular echo-intensity of the quadriceps by ultrasound is more related to the improvement of gait independence than an increase of muscle thickness in older inpatients. Intervention for intramuscular adipose tissue of the quadriceps may be important for improving gait independence in older inpatients.

Higher Body Mass Index in Hospitalized Older Patients Is Related to Higher Muscle Quality

OBJECTIVES

This study aimed to examine the relationship between muscle mass, intramuscular adipose tissue, and body mass index (BMI) in older inpatients.

DESIGN

Cross-sectional study.

SETTING

Hospital-based study.

PARTICIPANTS

This study included 413 inpatients aged ≥ 65 years (186 men and 227 women).

MEASUREMENTS

Muscle mass and intramuscular adipose tissue of the quadriceps were assessed by measuring the muscle thickness and echo intensity on ultrasound images. To examine the relationship between quadriceps thickness and echo intensity and BMI in total participants and each sex, the Kendall rank correlation coefficient was used. Multiple regression analysis was performed to examine whether BMI was independently and significantly related to the quadriceps thickness and echo intensity, even after adjusting for other variables for total participants and each sex. The independent variables in multiple regression analyses were BMI, age, disease, days from onset disease.

RESULTS

The results of the correlation analyses showed that BMI was significantly related to the quadriceps thickness (total participants, τ = 0.431; men, τ = 0.491; women, τ = 0.388) and echo intensity (total participants, τ = -0.239; men, τ = -0.318; women, τ = -0.188). In the multiple regression analysis, BMI was independently and significantly associated with the quadriceps thickness (total participants, β = 0.535; men, β = 0.548; women, β = 0.519) and echo intensity (total participants, β = -0.287; men, β = -0.398; women, β = -0.210).

CONCLUSION

This study indicated that older inpatients with a higher BMI have greater muscle mass and less intramuscular adipose tissue of the quadriceps. These results suggested that a higher BMI in older inpatients is related to higher quadriceps muscle quality.

A new aiming guide can create the tibial tunnel at favorable position in transtibial pullout repair for the medial meniscus posterior root tear

INTRODUCTION

Injuries to the medial meniscus (MM) posterior root lead to accelerated cartilage degeneration of the knee. An anatomic placement of the MM posterior root attachment is considered to be critical in transtibial pullout repair of the medial meniscus posterior root tear (MMPRT). However, tibial tunnel creation at the anatomic attachment of the MM posterior root is technically difficult using a conventional aiming device. The aim of this study was to compare two aiming guides. We hypothesized that a newly-developed guide, specifically designed, creates the tibial tunnel at an adequate position rather than a conventional device.

MATERIALS AND METHODS

Twenty-six patients underwent transtibial pullout repairs. Tibial tunnel creation was performed using the Multi-use guide (8 cases) or the PRT guide that had a narrow twisting/curving shape (18 cases). Three-dimensional computed tomography images of the tibial surface were evaluated using the Tsukada's measurement method postoperatively. Expected anatomic center of the MM posterior root attachment and tibial tunnel center were evaluated using the percentage-based posterolateral location on the tibial surface. Percentage distance between anatomic center and tunnel center was calculated.

RESULTS

Anatomic center of the MM posterior root footprint located at a position of 78.5% posterior and 39.4% lateral. Both tunnels were anteromedial but tibial tunnel center located at a more favorable position in the PRT group: percentage distance was significantly smaller in the PRT guide group (8.7%) than in the Multi-use guide group (13.1%).

DISCUSSION

The PRT guide may have great advantage to achieve a more anatomic location of the tibial tunnel in MMPRT pullout repair.

LEVEL OF EVIDENCE

III.

The differential expression of mgl mRNA by Porphyromonas gingivalis affects the production of methyl mercaptan

OBJECTIVE

A large number of individuals have halitosis. The total amount of volatile sulfur compounds, which are the main cause of halitosis, has been correlated with periodontitis following bacterial infection. In this study, Porphyromonas gingivalis (Pg), a major periodontopathogenic bacterium, was isolated from patients with halitosis by the amplification of 16S rRNA, and the ability of isolated Pg to produce methyl mercaptan (CH3 SH) was determined to clarify the relationship between halitosis and Pg infection.

MATERIALS AND METHODS

CH3 SH concentrations were measured in patients using Oral Chroma. The production of CH3 SH by Pg standard and clinical strains was also measured in vitro. Real-time PCR was performed to compare the expression of mgl mRNA (which encoded l-methionine-a-deamino-g-mercaptomethane-lyase) among the Pg strains. The production of CH3 SH and the expression of mgl mRNA were also determined to assess the effects of oriental medicine.

RESULTS

The production of CH3 SH and the expression of mgl mRNA strongly correlated with each other in the presence of l-methionine. The expression of mgl mRNA by Pg W83 was strongly inhibited by magnoliaceae.

CONCLUSION

The production of CH3 SH was correlated with the expression of mgl. Furthermore, the oriental medicine, magnoliaceae, may represent a potential treatment for halitosis.

The effects of ADL on recovery of swallowing function in stroke patients after acute phase

This study aimed to examine the association between the degree of recovery from dysphagia and changes in functional independence measure (FIM) items in stroke patients after acute phase by conducting a historical cohort study, because none explains the effects of activities of daily living (ADL) on recovery of swallowing function. Study patients included hospitalised stroke patients after acute phase in whom dysphagia was confirmed (n = 72). Change in nutritional intake method score was examined for association with age, days from stroke onset to admission, length of hospital stay and change in FIM score. Moreover, to examine characteristics of patients who were removed from tube feeding, all patients who required tube feeding at the time of admission were divided into two groups comprising those who required tube feeding at discharge and those who did not. A significant and positive association was observed between change in nutritional intake method and FIM for all items other than self-care of bathing, locomotion of stairs and problem solving. Patients who were removed from tube feeding were significantly younger than those who required tube feeding at the time of discharge (P < 0.041) and also showed significantly higher FIM scores for transfer and all cognitive FIM items at the time of admission (P < 0.05). This study demonstrated that nutritional intake methods improve in conjunction with FIM improvements in patients with dysphagia following the acute phase of stroke. Our results suggest that the age and cognitive function may influence the recovery of patient ability of oral intake.

Volatile and nonvolatile selective switching of a photo-assisted initialized atomic switch

A photo-assisted atomic switch, which has a photoconductive molecular layer in a gap of about 20 nm between an Ag2S electrode and a Pt electrode, is set to a conventional gap-type atomic switch operation mode by light irradiation with the application of a small bias that precipitates Ag atoms from an Ag2S electrode. After this initialization, the switch operates only with application of a bias. In this study, we also found that after the set-operation a photo-assisted initialized atomic switch shows different switching modes depending on the bias range, i.e., volatile switching when the applied bias is smaller than the threshold bias, and nonvolatile switching when the applied bias is larger than the threshold bias. These characteristics can be useful in reconfiguring a circuit such as in neural computing systems.

Assessment of the Plasma/Serum IgG Test to Screen for Periodontitis

Chronic periodontitis is a silent infectious disease prevalent worldwide and affects lifestyle-related diseases. Therefore, efficient screening of patients is essential for general health. This study was performed to evaluate prospectively the diagnostic utility of a blood IgG antibody titer test against periodontal pathogens. Oral examination was performed, and IgG titers against periodontal pathogens were measured by ELISA in 1,387 individuals. The cut-off value of the IgG titer was determined in receiver operating characteristic curve analysis, and changes in periodontal clinical parameters and IgG titers by periodontal treatment were evaluated. The relationships between IgG titers and severity of periodontitis were analyzed. The best cut-off value of IgG titer against Porphyromonas gingivalis for screening periodontitis was 1.682. Both clinical parameters and IgG titers decreased significantly under periodontal treatment. IgG titers of periodontitis patients were significantly higher than those of healthy controls, especially in those with sites of probing pocket depth over 4 mm. Multiplied cut-off values were useful to select patients with severe periodontitis. A blood IgG antibody titer test for Porphyromonas gingivalis is useful to screen hitherto chronic periodontitis patients (ClinicalTrials.gov number NCT01658475).

Preparative purification of gentamicin components using high-speed counter-current chromatography coupled with electrospray mass spectrometry

We developed a useful and preparative method based on high-speed counter-current chromatography with mass spectrometry (HSCCC/MS) to purify gentamicin C1a, C2/2a and C1 from standard powder. The analytes were purified on the HSCCC model CCC-1000 (multi-layer coil planet centrifuge) with a volatile two-phase solvent system composed of n-butanol/10% aqueous ammonia solution (50:50, v/v) and detected on an LCMS-2020EV quadrupole mass spectrometer fitted with an electrospray ionization (ESI) source system in positive ionization following scan mode (m/z 100-500). The HSCCC/ESI-MS peaks indicated that gentamicin C1a (m/z 450: [M+H](+)), C2/2a (m/z 464: [M+H](+)) and C1 (m/z 478: [M+H](+)) have the peak resolution values of 1.3 and 1.7 from 30 mg of loaded gentamicin powder. The HSCCC yielded 3.9 mg of gentamicin C1a, 12.6 mg of gentamicin C2/2a and 12.0 mg of gentamicin C1. These purified substances were analyzed by LC/MS with scan positive-mode. Based on the LC/MS chromatograms and spectra of the fractions, analytes were estimated to be over 95% pure. These gentamicin isomers of C1a, C2/2a and C1 were evaluated for their antibacterial activities. The overall results indicate that this approach of HSCCC/MS is a powerful technique for the purification of gentamicin components.

On-line solid-phase extraction LC-MS/MS for the determination of Ac-SDKP peptide in human plasma from hemodialysis patients

We developed a high-throughput method based on on-line solid-phase extraction liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) to determine N-terminal thymosin-β fragment peptide (N-acetyl-seryl-aspartyl-lysyl-proline, Ac-SDKP) in human plasma samples. Quantification of Ac-SDKP was performed using direct injection for on-line SPE based on C(18), reversed-phase LC separation and stable isotope dilution electrospray ionization-MS/MS in multiple reaction-monitoring (MRM) mode. The Ac-SDKP-(13)C(6), (15)N(2) (m/z 496 → 137) was synthesized for the internal standard. The MRM ion for Ac-SDKP was m/z 488 → 129 (quantitative ion)/226. The limit of detection and lower limit of quantitation were 0.05 and 0.1 ng/mL in standard solution, respectively. Recovery values were 98.3-100.4% with inter-day (relative standard deviation, RSD, 0.4-14.1%) and intra-day (RSD, 0.8-19.7%) assays. This method was applied to the measurement of Ac-SDKP levels in plasma from hemodialyzed subjects. Concentrations were 0.59 ± 0.23 ng/mL (pre-hemodialyzed subjects, n = 9) and 0.44 ± 0.19 ng/mL (post-hemodialyzed subjects, n = 9). All plasma Ac-SDKP levels were decreased by dialysis. Thus, plasma Ac-SDKP was decreased through dialysis in chronic kidney disease. The findings in this study will be useful for the treatment of anemia in chronic kidney disease with dialysis.

The Analysis of Drug Release from Diluted Water/oil/water Emulsions by a Model of the Rupture of Oil Membrane

The release behaviour of theophylline encapsulated in the inner aqueous phase of a water/oil/water emulsion was investigated by two methods. A cellulose tube containing a sample of the emulsion was placed in a rotary basket and was stirred in a dissolution medium (Method A), or the w/o/w emulsion was dispersed in a dissolution medium and the system was stirred by a paddle, allowing the drug to permeate into a cellulose tube placed in the dispersing medium (Method B).

In Method A, the drug release rate from the emulsion decreased with increase in the concentration of sodium chloride co-formulated with the drug in the inner aqueous phase. The drug release rate in the dissolution test medium No. 1 or No. 2 of the JP XII was greater than that in purified water and was increased with the ionic strength of the dissolution medium. The drug was released more rapidly in Method B than in Method A, because the emulsion was destroyed more easily using the former method. As this destruction of emulsion structure occurred immediately after dilution with dissolution medium, the influence of the dissolution medium on the release profile could not be detected using Method B.

The experimental data of drug release were satisfactorily explained by the destruction model of the oil membranes of the water/oil/water emulsions.

Quantification of N-acetyl-seryl-aspartyl-lysyl-proline in hemodialysis patients administered angiotensin-converting enzyme inhibitors by stable isotope dilution liquid chromatography-tandem mass spectrometry

We developed a sensitive, selective and accurate method based on liquid chromatography with tandem mass spectrometry (LC-MS/MS) to determine N-terminal thymosin-β peptides of Ac-SDKP and Ac-ADKP in human plasma samples. Quantification of Ac-SDKP and Ac-ADKP was performed using solid phase extraction (SPE) based on C(18), reversed phase LC separation, and stable isotope dilution electrospray ionization-MS/MS in multiple reaction-monitoring (MRM) mode. The Ac-SDKP-(13)C(6), (15)N(2) and Ac-ADKP-d(7) were synthesized for the internal standards. These MRM monitoring ions were m/z 488→129 (quantitative ion)/226 for Ac-SDKP, m/z 496→137 for Ac-SDKP-(13)C(6), (15)N(2), m/z 472→129 (quantitative ion)/226 for Ac-ADKP, and m/z 479→129 for Ac-ADKP-d(7), respectively. Lower limit of quantitation (LLOQ) of Ac-SDKP and Ac-ADKP was 0.1ng/mL in human plasma. Recovery values were ranged from 94.7% to 106.3% for inter- (RSD: 0.6-3.5%) and intra- (RSD: 0.4-4.9%) day assays. Plasma Ac-SDKP levels were significantly higher in hemodialyzed subjects treated with angiotensin-converting enzyme inhibitors of enalapril (27.3±24.6ng/mL, n=10) and trandolapril (12.3±16.9ng/mL, n=18) than healthy (0.4±0.2ng/mL, n=7) and hemodialyzed subjects (0.6±0.2ng/mL, n=34). This analytical method would be useful to measure N-terminal thymosin-β peptides in human plasma for the clinical study.

Development and application of an HILIC-MS/MS method for the quantitation of nucleotides in infant formula

A method for the quantitation of nucleotides (adenosine 5'-monophosphate (AMP), guanosine 5'-monophosphate (GMP), uridine 5'-monophosphate (UMP), cytidine 5'-monophosphate (CMP), and inosine 5'-monophosphate (IMP)) in infant formula was developed by hydrophilic interaction chromatography with tandem mass spectrometry (HILIC-MS/MS). The internal standards used (AMP-13C10, 15N5; GMP-13C10, 15N5; UMP-13C9, 15N2; CMP-13C9, 15N3) were prepared with centrifugal ultrafiltration (CUF). Data acquisition was achieved by using multiple reaction monitoring (MRM) of product ions of protonated molecules of the five nucleotides generated by the positive-ion ESI. HILIC conditions were performed with 30 mmol/L ammonium formate in water (pH 2.5, adjusted with formic acid) and methanol. The LOD and LOQ were 5-10 μg/mL and 10-30 μg/mL for standard solution, respectively. Recovery for intra- and interday assays ranged from 98.1 to 108.9% (RSD: 0.7-5.4%) spiked with three concentration levels (5, 25, and 250 μg/g powder infant formula). This method could be applied for the determination of nucleotides in infant formula samples. The detected concentrations of five nucleotides ranged from not detected (n.d.) to 278 μg/g powder infant formula. The total nucleotide level ranged from n.d. to 600.2 μg/g powder infant formula.

Simple and novel screening assay of natural antioxidants for Cu(II) ion/adrenaline-mediated oxidation of N-terminal amyloid beta by liquid chromatography/mass spectrometry

In the present study, a novel assay for screening inhibitors of Cu(II) ion/adrenaline-mediated oxidative modification of N-terminal amyloid beta (Abeta) peptides was developed using liquid chromatography with mass spectrometry (LC/MS). The physiological condition of Cu(II) ion/adrenaline in buffer (pH 7.4) at 37 degrees C for 90 min revealed a specific modification of N-terminal Abeta peptides, such as Abeta1-6, Abeta1-40, and Abeta1-42, using trypsin digestion and LC/MS detection of the modified Abeta peptide. When this oxidative modification of the shorter N-terminal Abeta1-6 was subjected to LC/MS, single charged ions from native peptide ([M+H]+, m/z 774) were observed at m/z 729 and 685, corresponding to a decrease in mass of 45 and 89 Da, respectively, as compared with the original peptide. To determine the effect of specific antioxidants, a screening assay to find inhibitors of Cu(II) ion/adrenaline-mediated oxidation was developed based on the response ratio of m/z 685 to 774. LC/MS detection of the modified peptides allowed us to identify antioxidants that inhibit oxidative modification of Abeta1-6 model peptide. The oxidative modification of Abeta1-6 was inhibited by curcumin but not an isoflavone or catechin mixture or saponin or capsaicin, revealing a clear difference between antioxidants that inhibit oxidative modification and other antioxidants. This novel assay may allow for the identification of antioxidants that protect against oxidative modification of Abeta and other proteins related to oxidative stress by adrenaline and Cu(II) ions under normal physiologic conditions.

Screening assay for metal-catalyzed oxidation inhibitors using liquid chromatography-mass spectrometry with an N-terminal beta-amyloid peptide

Production of microregional catalytic reactive oxygen species (ROS) by metal-binding amyloid-beta (Abeta) peptides mediates the neurotoxicity of Alzheimer's disease, and inhibitors of this activity may be of therapeutic value. No current analytical methods target specific ROS inhibitors produced by metal-binding peptides. We report a screening assay for metal-catalyzed oxidation (MCO) inhibitors based on liquid chromatography-mass spectrometry (LC-MS) with a model N-terminal Abeta peptide (Abeta(1-6)). When subjected to MCO by Cu(II)/ascorbic acid, singly and doubly charged Abeta(1-6) molecules were observed at m/z 729.2 and 364.8 and m/z 685.3 and 343.3, respectively, corresponding to a decrease in mass of 45 and 89 Da compared with the model peptide. In contrast, H(2)O(2) did not modify the Abeta(1-6) peptide. Modified peptides were characterized by a specific MCO of Abeta(1-6), which contains both His and N-terminal Asp residues. LC-MS detection of the modified peptides allowed us to identify antioxidants that inhibit MCO of Abeta(1-6). MCO of the model peptide was inhibited by curcumin, but not dibutylhydroxytoluene, carotene, tocopherol, estradiol or nicotine, revealing a clear difference between curcumin and other antioxidants. This novel assay may allow for the identification of antioxidants that protect against MCO of peptides and proteins related to degenerative diseases.

A valid model for the mechanism of oxidation of tryptophan to formylkynurenine-25 years later

The dye-sensitized photooxygenation of DL-tryptophan in aqueous solution leads to the tricyclic compound 2-carboxy-3a-hydroperoxy-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole which, on reduction with dimethyl sulfide, furnishes two diastereoisomeric alcohols separable by fractional crystallization into a higher melting (mp 254 degrees -256 degrees ) and a lower melting (mp 228 degrees ) diastereoisomer. Each of these alcohols was correlated with one of the analogous pair of isomeric 1,2-dicarbomethoxy analogs by alkaline hydrolysis and by x-ray analysis. In this way, the 3a-hydroxy-1,2-dimethoxycarbonyl- 1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole, mp 163 degrees -164 degrees , was shown to have the trans configuration with regard to the relative positions of the hydroxyl and carbomethoxy groups and that, on alkaline hydrolysis, it produced the isomer with mp 228 degrees , which therefore also has the trans configuration. The mechanism of the smooth thermal rearrangement of the (presumably ring-chain tautomeric) tryptophan hydroperoxy intermediates to formylkynurenine is discussed with its implications for the biological oxidation by tryptophan 2,3-dioxygenase.

Substrate Preference in a Strain of Megasphaera elsdenii, a Ruminal Bacterium, and Its Implications in Propionate Production and Growth Competition

The NIAH 1102 strain of Megasphaera elsdenii utilized lactate in preference to glucose when the two substrates were present. Even when lactate was supplied to cells fermenting glucose, the cells switched substrate utilization from glucose to lactate and did not utilize glucose until lactate decreased to a low concentration (1 to 2 mM). Since substrate utilization was shifted gradually without intermittence, typical diauxic growth was not seen. The cyclic AMP content did not rise markedly with the shift in substrate utilization, suggesting that this nucleotide is not involved in the regulation of the shift. It was unlikely that propionate was produced from glucose, which was explicable by the fact that lactate racemase activity dropped rapidly with the exhaustion of lactate and cells actively fermenting glucose did not possess this enzyme. A coculture experiment indicated that M. elsdenii NIAH 1102 is overcome by Streptococcus bovis JB1 in the competition for glucose, mainly because M. elsdenii NIAH 1102 is obliged to utilize lactate produced by S. bovis JB1; i.e., glucose utilization by M. elsdenii NIAH 1102 is suppressed by the coexistence of S. bovis JB1.

Simultaneous determination of avermectins in bovine tissues by LC-MS/MS

Analytical method for the simultaneous quantification of avermectins (AVMs), abamectin B1a, abamectin 8,9-Z isomer B1a, emamectine benzoate B1a, emamectine benzoate 8,9-Z isomer B1a, ivermectin, eprinomectin B1a, doramectin and moxidectin in bovine tissues (muscle, liver and fat) was developed by LC-MS/MS in electrospray positive ion mode. The separation was achieved on a short TSK-GEL ODS 100V column with the mobile phase consisting of acetonitrile and aquatic 0.1 mM ammonium formate containing 0.1% formic acid v/v at a flow rate of 0.2 mL/min with gradient elution. Liquid-liquid extraction with isooctane was used for the sample extraction/preparation of analytes in bovine samples. The linearity of the calibration curves was excellent in matrix-matched standards, and yielded the coefficients (r(2)=0.997-0.999, range from LOQ to 500, 1000 or 5000 ng/g) of determination of the target analytes. Recoveries were in the range of 87.9-99.8% with associated precision values (within-day: 1.5-7.4%, n=6, and between-day: 1.5-8.4% for 3 days) for repeatability and reproducibility. LC-MS/MS method has been proven to be highly efficient and suitable for the simultaneous determinations of eight AVMs in bovine tissue samples.