Effects of watershed land use on coastal marine environments: A multiscale exploratory analysis with multiple biogeochemical indicators in fringing coral reefs of Okinawa Island.

The analytical spatial scale and selection of biogeochemical indicators affect interpretations of land-use impacts on coastal marine environments. In this study, nine biogeochemical indicators were sampled from 36 locations of coral reefs fringing a subtropical island, and their relationships with watershed land use were assessed by spatial autoregressive models with spatial weight matrixes based on distance thresholds of a few to 30 km. POM-relevant indicators were associated with agricultural and urban lands of watersheds within relatively small ranges (6-14 km), while the concentrations of inorganic nutrients were associated with watersheds within 20 km or more. The macroalgal δ15N showed a strong relationship with agricultural lands of watersheds within 7 km and urban/forest lands of watersheds within 24 km. These results demonstrate significant effects of land use on the coral reef ecosystems of the island, and the importance of appropriate combinations of analytical scales and biogeochemical indicators.

Prospective monitoring of carbapenem use and pseudomonal resistance across pediatric institutions.

OBJECTIVE: To determine whether carbapenem consumption and Pseudomonas aeruginosa resistance rates can be used as benchmarks to compare and improve antimicrobial stewardship programs across multiple pediatric hospitals. DESIGN: A prospective study. SETTING AND PARTICIPANTS: Healthcare institutions in Japan with >100 pediatric beds. METHODS: An annual survey of the total days of therapy (DOT) per 1,000 patient days for carbapenem antibiotics (meropenem, imipenem-cilastatin, panipenem-betamipron, doripenem) and susceptibility rates of Pseudomonas aeruginosa to meropenem and imipenem-cilastatin from each institution was conducted over a 7-year period. Data were reported to the administration, as well as to the infection control team, of each institution annually. RESULTS: Data were obtained from 32 facilities. The median total carbapenem DOT per 1,000 patient days was 16.6 and varied widely, with a range of 2.7 to 59.0. The median susceptibility to meropenem was 86.6%, ranging from 78.6% to 96.6%. We detected an inverse correlation between total carbapenem DOT versus susceptibility (r = - 0.36; P < .01). Over the 7-year period, the DOT per 1,000 patient days of carbapenem decreased by 27% from a median of 16.0 to 11.7 (P < .01). We also observed an improvement in susceptibility to meropenem from a median of 87% to 89.7% (P = .01) and to imipenem-cilastatin from 79% to 85% (P < .01). The decreases in the use of carbapenem were greater in institutions with antimicrobial stewardship programs led by pediatric infectious disease specialists. CONCLUSIONS: Antimicrobial use and resistance, targeting carbapenems and P. aeruginosa, respectively, can serve as benchmarks that can be utilized to promote antimicrobial stewardship across pediatric healthcare institutions.

Size-exclusion chromatography combined with solution X-ray scattering measurement of the heat-induced aggregates of water-soluble proteins at low ionic strength in a neutral solution.

The heat-induced (80 ±â€¯1 ℃, 1 h) aggregates of bovine serum albumin and ovalbumin at neutral pH and low ionic strength (10 mM sodium phosphate buffer, pH 6.9) were characterized using size-exclusion chromatography combined with small-angle X-ray scattering measurement. The values calculated for the radius of gyration and molecular weight of the eluted aggregates of the bovine serum albumin were 9-11 nm and 540,000-820,000, respectively. Those of ovalbumin were 11-16 nm and 500,000-1,820,000, respectively. The overall linear conformation of the bovine serum albumin aggregates slightly differed from that of the ovalbumin aggregates since the mass fractal dimensions were found from calculation to be 1.63-1.7 for the bovine serum albumin and 1.36-1.51 for the ovalbumin. The surface property of the aggregates of both proteins was suggested to be similar to that of their native monomer since all the surface fractal dimensions were almost equivalent. The dimensionless Kratky plots of the eluted aggregates indicated that the non-globular conformation of the bovine serum albumin aggregates differs from that of the ovalbumin aggregates. These analyses using size-exclusion chromatography combined with the solution X-ray scattering measurement will be helpful for characterization of the components of the denatured protein aggregation in solution.

Assessment study of ion-exchange chromatography combined with solution X-ray scattering measurement for protein characterization.

The performance of ion-exchange chromatography combined with small-angle X-ray scattering measurement was evaluated by characterization of the hen egg white lysozyme as a model protein. The X-ray transmittance was estimated using a micro-ionization chamber equipped with a sample cell holder for the real-time monitoring of the X-ray beam strength through the salt gradient elution. The radius of gyration of the eluted protein was estimated to be 1.50 ±â€¯0.06 (n = 3) nm and 1.4 ±â€¯0.1 nm as the value at the zero protein concentration. By using the X-ray transmittance values for the scattering intensity correction, the molecular weight of the eluted protein was estimated to be 15,200 ±â€¯500 (n = 3) and 14,400 ±â€¯200 as the value at the zero protein concentration. These values are close to those of the monomer of this protein. The ion-exchange chromatography combined with the small-angle X-ray scattering measurement system equipped with the X-ray transmittance monitor is a reliable method for protein characterization in solution.

Feasibility of Diffusion Tensor Imaging at 1.5T Using Multi-Band Echo Planar Acquisition.

We report that diffusion tensor imaging (DTI) and tractography (DTT) of the pyramidal tracts using multi-band (MB) EPI could be a useful tool with a 1.5T MRI. We compared images using single-band EPI (SB-EPI) and MB-EPI. MB-EPI could reduce the scanning time by about 40%. We demonstrated that it is comparable between image qualities of SB-EPI and MB-EPI using tract-specific analysis and dice coefficients. Therefore, MB-EPI can promote high-speed DTI and DTT in clinical applications.

T2 and Apparent Diffusion Coefficient of MRI Reflect Maturation of Tissue-Engineered Auricular Cartilage Subcutaneously Transplanted in Rats.

In cartilage regenerative medicine, autologous chondrocyte implantation (ACI) has been applied clinically for partial defects of joint cartilage or nasal augmentation. To make treatment with ACI more effective and prevalent, modalities to evaluate the quality of transplanted constructs noninvasively are necessary. In this study, we compared the efficacy of several noninvasive modalities for evaluating the maturation of tissue-engineered auricular cartilage containing a biodegradable polymer scaffold. We first transplanted tissue-engineered cartilage consisting of human auricular chondrocytes, atelocollagen gel, and a poly-l-lactic acid (PLLA) porous scaffold subcutaneously into the back of athymic nude rats. Eight weeks after transplantation, the rats were examined by magnetic resonance imaging (MRI), X-ray, and ultrasound as noninvasive modalities. Then, the excised constructs were examined by histological and biochemical analysis including toluidine blue (TB) staining, glycosaminoglycans content, and enzyme-linked immunosorbent assay of type II collagen. Among the modalities examined, transverse relaxation time (T2) and apparent diffusion coefficient of MRI showed quite a high correlation with histological and biochemical results, suggesting that these can effectively detect the maturation of tissue-engineered auricular cartilage. Since these noninvasive modalities would realize time-course analysis of the maturation of tissue-engineered auricular cartilage, this study provides a substantial insight for improving the quality of tissue-engineered cartilage, leading to improvement of the quality and technique in cartilage regenerative medicine.

High rate of inducible clindamycin resistance in Staphylococcus aureus isolates--a multicenter study in Tokyo, Japan.

The resistance of Staphylococcus aureus (S. aureus) to antibiotics is an increasing problem. Clindamycin has been used as empiric therapy for the rising incidence of community-acquired methicillin-resistant S. aureus (MRSA). As such, the local rate of inducible resistance against clindamycin is an important consideration. This multicenter study was conducted to identify the incidence of inducible clindamycin resistance of S. aureus isolates in Tokyo, the most populous city in Japan. A total of 2408 adult and pediatric samples were collected from a university hospital and two pediatric hospitals between January 2011 and December 2011. Among the 2341 samples analyzed, the incidence of inducible clindamycin resistance in erythromycin-resistant and clindamycin-susceptible/intermediate isolates was found to be 91% (n = 585), a figure much higher compared to most reports from other countries. In conclusion, we found a very high rate of inducible clindamycin resistance in macrolide-resistant S. aureus isolates in our geographic area.

[Study on cine view of relative enhancement ratio map in O2-enhanced MRI].

Magnetic resonance imaging (MRI) enables the evaluation of organ structure and function. Oxygen-enhanced MRI (O2-enhanced MRI) is a method for evaluating the pulmonary ventilation function using oxygen as a contrast agent. We created the Cine View of Relative Enhancement Ratio Map (Cine RER map) in O2-enhanced MRI to easily observe the contrast effect for clinical use. Relative enhancement ratio (RER) was determined as the pixel values of the Cine RER map. Moreover, six healthy volunteers underwent O2-enhanced MRI to determine the appropriate scale width of the Cine RER map. We calculated each RER and set 0 to 1.27 as the scale width of the Cine RER map based on the results. The Cine RER map made it possible to observe the contrast effect over time and thus is a convenient tool for evaluating the pulmonary ventilation function in O2-enhanced MRI.

Reduced efficacy of ivermectin treatments in gastrointestinal nematode infections of grazing cattle in Japan.

Fecal egg count reduction tests (FECRT) and larval migration inhibition tests (LMIT) were conducted to assess the efficacy of ivermectin (IVM) against gastrointestinal nematodes on 2 cattle farms in northern Japan in 2009 and 2010. Twelve to 20 calves on each farm were treated topically with 0.5 mg IVM/kg 2 (Farm 2) or 4 times (Farm 1) during the grazing season (May-October). On Farm 1, fecal egg count (FEC) reduction at 14 days post-treatment ranged from 16 to 87% in 2009 and from 24 to 96% in 2010, with relatively low reductions in August and October (16-53%). Conversely, IVM treatment on Farm 2 reduced FEC by 97% in September 2009. Larvae obtained from fecal cultures and identified by PCR-RFLP analysis revealed that the dominant species on both farms prior to IVM administration was Cooperia oncophora. In 2009, the FEC reduction of C. oncophora on Farm 1 decreased from 85% in May to 56% in August. In 2010, the reduction in C. oncophora in August was 28%. In the LMIT using larvae collected from the fecal cultures on Farm 1 in May and August 2009, the EC50 value of IVM in C. oncophora in August (0.892 µg/ml) was 3 times higher than that in May (0.296 µg/ml). The results of the LMIT corroborated the FECRT data, indicating the presence of IVM-resistant C. oncophora on Farm 1, at least in August. This is the first report of IVM-resistant nematodes in Japanese cattle.

The effects on gastric emptying and carbohydrate loading of an oral nutritional supplement and an oral rehydration solution: a crossover study with magnetic resonance imaging.

BACKGROUND: Preoperative administration of clear fluids by mouth has recently been endorsed as a way to improve postoperative outcomes. A carbohydrate-containing beverage supplemented with electrolytes or proteins may have additional benefits for patients' satisfaction. However, effects on gastric residual, nausea, and emesis and the effectiveness of these beverages for improving patients' hydration status have not been well defined. METHODS: We evaluated changes in gastric volume over time by magnetic resonance imaging, as well as blood glucose levels, before and after administration of 500 mL oral rehydration solution (ORS) containing 1.8% glucose and electrolytes in 10 healthy volunteers. The same volume of an oral nutritional supplement (ONS) containing 18% glucose and supplemental arginine (545 mOsm/kg) was given to the same population using a crossover design. RESULTS: The mean (median, 95% confidence interval) gastric fluid volume at 1 hour after oral ingestion was 55.0 (55.3, 39.0-70.9) mL in the ORS group, whereas 409.2 (410.9, 371.4-447.0) mL in the ONS group (P = 0.0002). The gastric fluid volume of all participants in the ORS group returned to <1 mL/kg at 90 minutes after ingestion, whereas none reached <1 mL/kg at 120 minutes in the ONS group. The ONS group showed a sustained increase in the blood glucose level after ingestion (P < 0.0001 to baseline at 30, 60, 120 minutes), while the ORS group showed an initial increase (P < 0.0001, P = 0.01, P = 0.205 at each time point). CONCLUSIONS: ORS supplemented with a small amount of glucose showed faster gastric emptying, which may make it suitable for preoperative administration. In contrast, ONS supplemented with arginine with a relatively low osmolality was associated with a longer time for gastric emptying, although it showed a sustained increase in blood glucose level.

Characterization of a large glycoprotein proteoglycan by size-exclusion chromatography combined with light and X-ray scattering methods.

The molecular weight and chain conformation of a proteoglycan derived from shark cartilage in solution were characterized by size-exclusion chromatography combined with low-angle laser light scattering and small-angle X-ray scattering methods. The total molecular weight of the proteoglycan was 3.9±0.2 million and the molecular weight of the main component was about 2.0±0.2 million. The X-ray scattering data revealed that the main components of the proteoglycan are nearly equal to a chain with excluded volume and their persistence lengths range from 13.5 to 16.4nm. These results show that size-exclusion chromatography combined with low-angle laser light scattering and small-angle X-ray scattering measurements are complementarily useful for characterization of large biopolymers in solution.

Visualization of bile movement using MRI spin-labeling technique: preliminary results.

OBJECTIVE: The purpose of this article is to noninvasively visualize intrabiliary bile movement using an MRI spin-labeling technique and administration of water, full-fat milk, and negative contrast agent as stimuli for bile excretion. SUBJECTS AND METHODS: Six healthy volunteers underwent three studies with each of three oral liquid agents (water, full-fat milk, and manganese chloride solution) for a total of 18 MRI studies. Oblique-coronal T2-weighted images of the common bile duct were acquired at an inversion time of 1500 milliseconds after pulse labeling using a spin-labeling technique with an inversion pulse, repeated at intervals of 22 seconds. Bile flow rate was measured before and for 50 minutes after administration of the oral liquid agents, and its correlation with the change in gallbladder volume was assessed. RESULTS: Both anterograde and retrograde intermittent bile movements were successfully visualized in the common bile duct. The summation of excreted bile volume calculated from spin-labeled images correlated significantly with a decrease in gallbladder volume (p = 0.011). Milk stimulated significantly prolonged bile flow; flow was momentary with manganese chloride and mild with water; however, gallbladder volume decreased only in milk studies (p = 0.003). Biliary flow early after oral intake correlated significantly with gallbladder contractility at 50 minutes after oral intake (p = 0.049). CONCLUSION: A new method for visualizing intrabiliary bile movement in semi-real time (22-second time resolution) using an MRI spin-labeling technique was proposed. Bile was shown to be excreted in a to-and-fro type of movement. Administration of water and negative contrast agent may induce temporary bile excretion.

The utility of anaerobic blood culture in detecting facultative anaerobic bacteremia in children.

Routine anaerobic blood culture is not recommended in children because obligate anaerobic bacteremia is rare in the pediatric population. However, a number of facultative anaerobic bacteria can cause community and hospital acquired infections in children and the utility of anaerobic blood culture for detection of these organisms is still unclear. We conducted a retrospective analysis of all blood culture samples (n = 24,356) at a children's hospital in Japan from October 2009 to June 2012. Among the samples that had paired aerobic and anaerobic blood cultures, 717 samples were considered clinically significant with 418 (58%) organisms detected from both aerobic and anaerobic cultures, 167 (23%) detected only from aerobic culture and 132 (18%) detected only from anaerobic culture. While most facultative anaerobes were detectable by aerobic culture, over 25% of Enterobacteriaceae and 15% of Staphylococcus sp. were detected from anaerobic cultures bottles only, suggesting its potential role in selected settings.

Estimated dietary exposure to mycotoxins after taking into account the cooking of staple foods in Japan.

Mycotoxins are commonly present in cereal grains and are not completely destroyed during their cooking and processing. When mycotoxins contaminate staple foods, the risk for exposure becomes serious. In East Asia, including Japan, rice is consumed as a staple food, and with the increasingly Westernized lifestyle, the consumption of wheat has increased. The mycotoxins commonly associated with rice and wheat are total aflatoxin (AFL) and ochratoxin A (OTA), respectively. This study examined the retention of AFL and OTA during the cooking of rice and pasta. AFL was retained at 83%-89% the initial level after the cooking of steamed rice. In pasta noodles, more than 60% of the OTA was retained. These results show that AFL and OTA are relatively stable during the cooking process, suggesting that a major reduction in the exposure to these mycotoxins cannot be expected to occur by cooking rice and pasta. The estimated exposure assessment at the high consumer level (95th percentile) and the mycotoxin contamination level determined by taking into account these reductions in the present study should be useful for the establishment of practical regulations for mycotoxins in staple foods.

Treatment of pyelonephritis caused by extended-spectrum ß-lactamase-producing Enterobacteriaceae in children.

Fifty-four children were diagnosed as pyelonephritis caused by extended-spectrum ß-lactamase-producing Enterobacteriaceae at the largest children's hospital in Japan. Although 32 (59%) patients were treated with antimicrobials that are ineffective against the organisms, 39 (72%) patients became afebrile ≤2 days and clinical outcome was excellent. Children with pyelonephritis caused by extended-spectrum ß-lactamase-producing Enterobacteriaceae can be successfully treated with noncarbapenem antimicrobials.

[Non-contrast magnetic resonance angiography for renal arteries using breath held inflow inversion recovery-fan shaped inward outward view ordering: impact on image quality by changing wait recovery time after data acquisition].

PURPOSE: We assessed the wait time of non-contrast renal artery magnetic resonance (MR) angiography with a single breath hold using inflow inversion recovery-fan shaped inward outward view ordering technique in normal volunteers. METHODS: The wait time (WT)-the duration between the data acquisition and the following inversion recovery pulse-was varied from 10 ms to 2000 ms, and the contrast ratio between the renal artery and the background structures for each WT was assessed quantitatively. A simulation was also performed. RESULTS: The contrast ratio between the renal artery and each background structure with 2000 ms of WT was higher than that with 10 ms of WT. The contrast ratio between the renal artery and renal cortex with 1500 ms of WT was also higher than that with 10 ms of WT. In the simulation, when WT lengthened, the residual longitudinal magnetization of each background structure lowered. CONCLUSION: The WT affects contrast; adjustment of WT should be added to the assessment of the imaging parameter.

Detection of liver metastasis: is diffusion-weighted imaging needed in Gd-EOB-DTPA-enhanced MR imaging for evaluation of colorectal liver metastases?

PURPOSE: We compared diagnostic ability for detecting hepatic metastases between gadolinium ethoxy benzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) on a 1.5-T system, and determined whether DWI is necessary in Gd-EOB-DTPA-enhanced MRI for diagnosing colorectal liver metastases. MATERIALS AND METHODS: We assessed 29 consecutive prospectively enrolled patients with suspected metachronous colorectal liver metastases; all patients underwent surgery and had preoperative Gd-EOB-DTPA-enhanced MRI. Overall detection rate, sensitivity for detecting metastases and benign lesions, positive predictive value, and diagnostic accuracy (Az value) were compared among three image sets [unenhanced MRI (DWI set), Gd-EOB-DTPA-enhanced MRI excluding DWI (EOB set), and combined set]. RESULTS: Gd-EOB-DTPA-enhanced MRI yielded better overall detection rate (77.8-79.0 %) and sensitivity (87.1-89.4 %) for detecting metastases than the DWI set (55.9 % and 64.7 %, respectively) for one observer (P < 0.001). No statistically significant difference was seen between the EOB and combined sets, although several metastases were newly detected on additional DWI. CONCLUSIONS: Gd-EOB-DTPA-enhanced MRI yielded a better overall detection rate and higher sensitivity for detecting metastases compared with unenhanced MRI. Additional DWI may be able to reduce oversight of lesions in Gd-EOB-DTPA-enhanced 1.5-T MRI for detecting colorectal liver metastases.

Fate of hypointense lesions on Gd-EOB-DTPA-enhanced magnetic resonance imaging.

PURPOSE: To investigate the natural outcome and clinical implication of hypointense lesions in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI. MATERIALS AND METHODS: Forty patients underwent Gd-EOB-DTPA-enhanced MRI for preoperative evaluation of HCC. Hypointense lesions in the hepatobiliary phase that were hypovascular 5mm of more were extracted for follow-up. We performed a longitudinal study retrospectively for these lesions regardless of whether classical HCC developed or emerged in a different area from that of the lesions being followed. RESULTS: Thirty one patients displayed 130 hypointense lesions on MRI and only nine showed no hypointense lesions. In total, 17 (13.1%) of 130 hypointense lesions on MRI developed into classical HCC. The cumulative rates for these lesions to develop into classical HCC were 3.2% at 1 year, 11.1% at 2 years and 15.9% at 3 years. The total occurrence rates of classical HCC (25.8% at 1 year, 52.6% at 2 years and 76.4% at 3 years) were higher compared to those regarding only occurrence of classical HCC from hypointense lesions on MRI (10.0% at 1 year, 35.6% at 2 years and 44.6% at 3 years), although no significant difference was observed (p=0.073). CONCLUSIONS: Hypointense lesions that are detected in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI have some malignant potential, although treating these lesions aggressively in patients who already have HCC may be too severe.

Further application of size-exclusion chromatography combined with small-angle X-ray scattering optics for characterization of biological macromolecules.

Size-exclusion chromatography (gel filtration chromatography or gel permeation chromatography) in conjunction with online synchrotron radiation solution small-angle X-ray scattering optics, absorbance, and/or refractive index detectors was further assessed by application of biological macromolecules, such as the hollow sphere protein complex, apoferritin, and a linear polysaccharide, pullulan. The net X-ray scattering patterns of the eluted 24-mer molecule of apoferritin showed the specific character for the hollow spherical shape. The chromatographic (time-resolved) X-ray scattering data of the linear polysaccharide pullulan revealed the flexible chain structure during the chromatographic separation in an aqueous solution. These further applications demonstrated that the present measurement technique will be useful for not only the determination of the radius of gyration value of less than about 10 nm and molecular weight below several hundred thousand but also for the structural characterization of the various macromolecules during the chromatography.