A piezoelectric drop-on-demand generator for accurate samples in capillary electrophoresis

In this work, we propose a piezoelectric droplet generator for injection of well-defined amounts of sample in capillary electrophoresis. We demonstrate stable, precise and drop-on-demand droplet formation for various solutions, with precise control of waveform driving piezoelectric crystal inside the ink-jet head. By tuning the waveform, we can also manipulate the droplet size and delivery frequency. This injector was used in sampling for capillary electrophoresis. As a state-of-the-art application, the analysis of theobromine, caffeine and theophiline using micellar electrokinetic chromatography was developed. The volume of sample (single droplet) analyzed in this experiment was 179 pL (RSD=1.2%, n=10). The detection limits for caffeine, theobromine, and theophiline are 0.02, 0.08 and 0.06 mM L(-1), respectively. Compared with conventional methods, the combination of picoliter droplet dispenser with capillary electrophoresis allows precise and accurate sampling, as well as for reduced sample consumption, which will prove to be an efficient tool in quantitative separation and analysis.

Development of a novel two dimensional surface plasmon resonance sensor using multiplied beam splitting optics

A novel two dimensional surface plasmon resonance (SPR) sensor system with a multi-point sensing region is described. The use of multiplied beam splitting optics, as a core technology, permitted multi-point sensing to be achieved. This system was capable of simultaneously measuring nine sensing points. Calibration curves for sucrose obtained on nine sensing points were linear in the range of 0–10% with a correlation factor of 0.996–0.998 with a relative standard deviation of 0.090–4.0%. The detection limits defined as S/N = 3 were 1.98 × 10⁻⁶–3.91 × 10⁻⁵ RIU. This sensitivity is comparable to that of conventional SPR sensors.

Na(+) /Ca(2+) exchanger 2-heterozygote knockout mice display decreased acetylcholine release and altered colonic motility in vivo

BACKGROUND

The Na(+) /Ca(2+) exchanger (NCX) is a plasma membrane transporter involved in regulating intracellular Ca(2+) concentrations. NCX is critical for Ca(2+) regulation in cardiac muscle, vascular smooth muscle, and nerve fibers. However, little is known about the physiological role of NCX in the myenteric neurons and smooth muscles of the gastrointestinal tract.

METHODS

To determine the role of NCX1 and NCX2 in gastrointestinal tissues, we examined electric field stimulation (EFS)-induced responses in the longitudinal smooth muscle of the distal colon in NCX1- and NCX2-heterozygote knockout mice.

KEY RESULTS

We found that the amplitudes of EFS-induced relaxation that persisted during EFS were greater in NCX2 heterozygous mice (HET) than in wild-type mice (WT). Under the nonadrenergic, noncholinergic (NANC) condition, EFS-induced relaxation in NCX2 HET was similar in amplitude to that of WT. In addition, an NCX inhibitor, YM-244769 enhanced EFS-induced relaxation but did not affect EFS-induced relaxation under the NANC condition, as in NCX2 HET. Unlike NCX2 HET, NCX1 HET displayed no marked changes in colonic motility. These results indicate that cholinergic function in the colon is altered in NCX2 HET. The magnitude of acetylcholine (ACh)-induced contraction in NCX2 HET was similar to that in WT. In contrast, EFS-induced ACh release was reduced in NCX2 HET compared with that in WT.

CONCLUSIONS & INFERENCES

In this study, we demonstrate that NCX2 regulates colonic motility by altering ACh release onto the myenteric neurons of the distal colon.

Clear association between serum levels of adipokines and T-helper 17-related cytokines in patients with psoriasis

BACKGROUND

Psoriasis represents one of the T-helper (Th)17-mediated autoimmune diseases, and has been shown to be associated with metabolic syndrome (MetS). It has been reported that some adipokines and Th17-related cytokines are altered in patients with psoriasis.

AIM

To examine the relationship between levels of adipokines and Th17-related cytokines in the serum of patients with psoriasis compared with healthy controls.

METHODS

We enrolled 30 patients with psoriasis and 30 normal controls in the study, and used ELISA to measure serum adipokines and Th17-related cytokines. The association between each adipokine and each cytokine was determined using Pearson correlation analysis. Multiple regression analysis using all adipokines and Th17-related cytokines as covariates was also performed.

RESULTS

Pearson correlation analysis showed a strong positive association between chemerin and resistin levels and between adiponectin and high molecular weight adiponectin in normal controls. By contrast, in patients with psoriasis, resistin levels were significantly positively associated with tumour necrosis factor-α, while there was a strong negative association between retinol binding protein-4 and interleukin (IL)-6 levels. Interestingly, a marked positive correlation between IL-22 and adiponectin was also found in patients with psoriasis. Leptin levels correlated positively with IL-6 in patients with psoriasis, but this did not reach significance. The correlations identified by the multiple regression analyses were almost identical to those from the Pearson analyses.

CONCLUSIONS

These data suggest that distinct interaction between adipokines and Th17 cytokines is involved in the pathogenesis of psoriasis.

Chemiluminescence immunoassay for a nonionic surfactant using a compact disc-type microfluidic platform

A simple and pump-free chemiluminescence immunoassay based on a compact disc (CD)-type microfluidic platform for the determination of alkylphenol polyethoxylates (APnEOs) is described. The method is based on a competitive immunoreaction of the anti-APnEOs antibody immobilized on the magnetic microbeads between APnEOs and horseradish peroxidase (HRP)-labeled APnEOs in the sample solution. The luminol solution containing H2O2 and enhancer is caused to flow from one reservoir in the platform to another by appropriate adjustment of the speed of the rotation of the disc. The detection limit was similar to that reported in our previous paper, i.e., 10 ppb according to IC80.

Chronic atherosclerotic mesenteric ischemia that started to develop symptoms just after anaphylaxis

An 83-year-old woman was referred to our emergency department with acute urticaria and sudden shortness of breath approximately 30 min after taking rectal diclofenac potassium for lumbago. After treatment with adrenaline and corticosteroids, the patient became hemodynamically stable and left the hospital on the next day. She attended our hospital 1 week after the onset of anaphylaxis because of repeated postprandial epigastric pain. No abnormal lesions were found in endoscopy. Radiographic selective catheter angiography revealed chronic mesenteric ischemia caused by atherosclerosis and abundant collateral arteries between the celiac trunk, the superior mesenteric artery and the inferior mesenteric artery. Patients with chronic mesenteric ischemia usually present with a clinical syndrome characterized by painful abdominal cramps and colic occurring typically during the postprandial phase. Fear of eating resulted in malnutrition. She was prescribed proton pump inhibitor, digestants, anticholinergic agents, serine protease inhibitors, prokinetics, antiplatelet agents and transdermal nitroglycerin intermittently, but these had no beneficial effects. It was most probable that this patient with chronic atherosclerotic mesenteric ischemia was suffering from functional abdominal pain syndrome induced by anaphylaxis. Since psychiatric disorders were associated with alterations in the processing of visceral sensation, we facilitated the patient's understanding of functional abdominal pain syndrome with the psychologist. Postprandial abdominal pain gradually faded after administration of these drugs and the patient left the hospital. Developing a satisfactory patient-physician relationship was considered more effective for the management of persistent abdominal pain caused by complicated mechanisms.

Performance of an organic photodiode as an optical detector and its application to fluorometric flow-immunoassay for IgA

The performance of an organic thin film photodiode (OPD), fabricated from a hetero-junction comprised of two layers of C(60) and a phthalocyanine-Cu(II) complex was evaluated by detecting the chemiluminescence generated from the reaction of luminol with horseradish peroxidase in the presence of H(2)O(2), and the fluorescence from resorufin, as an optical detector. The photocurrent of the OPD was linear with respect to the power of light from a commercial LED. The sensitivity of the OPD was sufficient for detecting chemiluminescence with a power 0.1μW/cm(2). The OPD was successfully used in a flow-immunoassay for IgA, a marker of human stress, in which a sandwich immunoassay was carried out on the microchip and the fluorescence from resorufin, produced by the enzymatic reaction, was detected. The detection limits for resorufin and IgA were 5.0μM and 16ng/mL, respectively. The photosensitivity of the OPD remained relatively constant for a minimum of one year.

Acute liver dysfunction in the course of norovirus gastroenteritis

A 48-year-old female with abdominal pain and malaise who showed delayed symptom of acute gastroenteritis came to see us. Her illness was diagnosed as norovirus infection, but liver dysfunction accompanied this gastroenteritis. We investigated the pathogenesis of this hepatitis for all causes including drugs, but we could not detect norovirus infection. The liver damage improved shortly in course of the gastroenteritis. She recovered completely within 2 weeks without any damage left. Norovirus-induced liver dysfunction is not known, and there is no report in the literature. We report, for the first time, the case of liver dysfunction with norovirus gastroenteritis.

Successful treatment of wound breakdown caused by pyoderma gangrenosum after total knee arthroplasty

Pyoderma gangrenosum is a rare ulcerative disorder of the skin of unknown etiology. We present a case of pyoderma gangrenosum that occurred following total knee arthroplasty, which was initially misdiagnosed as severe wound infection. Repeated debridement procedures resulted in a large soft tissue defect around the anterior knee joint. The patient was treated successfully with a latissimus dorsi musculocutaneous flap under immunosuppressive therapy. Pyoderma gangrenosum is often misdiagnosed as an infected wound, but the treatment for theses differential diagnoses is completely different. When a lesion is refractory to thorough treatment for infection, a diagnosis of pyoderma gangrenosum should be considered.

Anti-aquaporin-4 antibody-positive neuromyelitis optica presenting with syndrome of inappropriate antidiuretic hormone secretion as an initial manifestation

The distribution of neuromyelitis optica (NMO)-characteristic brain lesions corresponds to sites of high aquaporin-4 (AQP4) expression, and the brainstem and hypothalamus lesions that express high levels of AQP4 protein are relatively characteristic of NMO. The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is one of the important causes of hyponatremia and results from an abnormal production or sustained secretion of antidiuretic hormone (ADH). SIADH has been associated with many clinical states or syndromes, and the hypothalamic-neurohypophyseal system regulates the feedback control system for ADH secretion. We report the case of a 63-year-old man with NMO, whose initial manifestation was hyponatremia caused by SIADH. Retrospective analysis revealed that the serum anti-AQP4 antibody was positive, and an MRI scan showed a unilateral lesion in the hypothalamus. SIADH recovered completely with regression of the hypothalamic lesion. As such, NMO should even be considered in patients who develop SIADH and have no optic nerve or spinal cord lesions but have MRI-documented hypothalamic lesions.

An integrated enzyme-linked immunosorbent assay system with an organic light-emitting diode and a charge-coupled device for fluorescence detection

A fluorescence detection system for a microfluidic device using an organic light-emitting diode (OLED) as the excitation light source and a charge-coupled device (CCD) as the photo detector was developed. The OLED was fabricated on a glass plate by photolithography and a vacuum deposition technique. The OLED produced a green luminescence with a peak emission at 512 nm and a half bandwidth of 55 nm. The maximum external quantum efficiency of the OLED was 7.2%. The emission intensity of the OLED at 10 mA/cm(2) was 13 μW (1.7 mW/cm(2)). The fluorescence detection system consisted of the OLED device, two band-pass filters, a five microchannel poly(dimethylsiloxane) (PDMS) microfluidic device and a linear CCD. The fluorescence detection system was successfully used in a flow-based enzyme-linked immunosorbent assay on a PDMS microfluidic device for the rapid determination of immunoglobulin A (IgA), a marker for human stress. The detection limit (S/N=3) for IgA was 16.5 ng/mL, and the sensitivity was sufficient for evaluating stress. Compared with the conventional 96-well microtiter plate assay, the analysis time and the amounts of reagent and sample solutions could all be reduced.

Flow immunoassay for nonioinic surfactants based on surface plasmon resonance sensors

A rapid, sensitive immunoassay based on a surface plasmon resonance sensor in a flow system for the determination of alkylphenol polyethoxylate (APEO) is described. The method is based on an indirect competitive reaction between an anti-APEO antibody in the sample solution and APEO immobilized on a sensor chip and APEO in the same sample solution. A sensor chip was prepared by immobilizing an APEO-horseradish peroxidase (APEO-HRP) conjugate on the thin gold film of the sensor chip. The adsorption constants for the APEO-HRP conjugate on the sensor chip and the surface density of the APEO-HRP adsorbed on the sensor chip at the saturated state were estimated to be 4.7 x 10(5) M(-1) and 5.0 x 10(-14) mol/mm(2), respectively, using a Langmuir adsorption isotherm equation and results from the adsorption experiments. The affinity constants for the immunocomplexes of the anti-APEO antibody with the APEO conjugate on the sensor chip and for APEO in the sample solution were estimated to 2.0 x 10(6) and 5.1 x 10(6) M(-1), respectively. A typical sigmoid calibration curve for APEO was obtained in the concentration range from 1 ppb to 1000 ppb. The detection limit, defined as the concentration of APEO, at which 85% of the sensor signal was observed, was ca. 10 ppb. The assay was applied to the determination of APEO in tap water in conjunction with a solid phase extraction pretreatment; APEO levels of approximately 50 ppt were successfully determined.

Isolation of microorganisms and substances inhibitory to aflatoxin production

Aflatoxins are toxic and carcinogenic secondary metabolites produced by Aspergillus flavus and A. parasiticus. The contamination of crops, feeds, and foods with aflatoxins can have serious effects on the health of humans and animals. Although many studies have been done to develop aflatoxin-control strategies, most are limited in their effectiveness. As part of an effort to develop control procedures, we have devised simple and safe methods that are useful for identifying microorganisms that effectively inhibit aflatoxin production by fungi. These include the microtitre agar plate assay using norsolorinic acid-accumulating mutant fungi, the ultraviolet light photography method using an instant film, the tip culture method, a convenient RNA extraction method for reverse transcription-polymerase chain reaction (RT-PCR) analysis, and other methods. Results of a recent trial have shown that Achromobacter xylosoxidans significantly inhibited aflatoxin production by A. parsiticus, and that the main inhibitory substance produced by the bacterium was cyclo(L-leucyl-L-prolyl). This result confirms that the methods described herein are useful for identifying microorganisms that inhibit aflatoxin production by fungi and could contribute to the development of methods to reduce aflatoxin contamination in commodities.

Mixed-lineage-leukemia (MLL) fusion protein collaborates with Ras to induce acute leukemia through aberrant Hox expression and Raf activation

Mixed-lineage-leukemia (MLL) fusion oncogenes are closely involved in infant acute leukemia, which is frequently accompanied by mutations or overexpression of FMS-like receptor tyrosine kinase 3 (FLT3). Earlier studies have shown that MLL fusion proteins induced acute leukemia together with another mutation, such as an FLT3 mutant, in mouse models. However, little has hitherto been elucidated regarding the molecular mechanism of the cooperativity in leukemogenesis. Using murine model systems of the MLL-fusion-mediated leukemogenesis leading to oncogenic transformation in vitro and acute leukemia in vivo, this study characterized the molecular network in the cooperative leukemogenesis. This research revealed that MLL fusion proteins cooperated with activation of Ras in vivo, which was substitutable for Raf in vitro, synergistically, but not with activation of signal transducer and activator of transcription 5 (STAT5), to induce acute leukemia in vivo as well as oncogenic transformation in vitro. Furthermore, Hoxa9, one of the MLL-targeted critical molecules, and activation of Ras in vivo, which was replaceable with Raf in vitro, were identified as fundamental components sufficient for mimicking MLL-fusion-mediated leukemogenesis. These findings suggest that the molecular crosstalk between aberrant expression of Hox molecule(s) and activated Raf may have a key role in the MLL-fusion-mediated-leukemogenesis, and may thus help develop the novel molecularly targeted therapy against MLL-related leukemia.

Video-assisted skin-sparing breast-conserving surgery for breast cancer and immediate reconstruction with autologous tissue: Clinical outcomes

e11580

Background: This study analyzed clinical results of video-assisted breast-conserving surgery for breast cancer. Methods: Video-assisted breast-conserving surgery is indicated for breast cancer that has not invaded the skin. A skin incision is made at an inconspicuous site. Skin-sparing partial mastectomy was performed endoscopically on 244 patients (stage I, n=94; stage II, n=150). Morbidity, curability and patient satisfaction were analyzed. Results: Skin necrosis was seen in 9 patients. Local recurrence was seen in 13 patients (mean postoperative interval, 65.3 months). Distant metastasis-free survival at 60 months was 93.6% for stage I and 90.5% for stage II. Overall survival was 95.7% for stage I and 96.9% for stage II. Satisfaction with surgery as investigated by questionnaire was “good” for 72.3% of patients. Conclusions: Video-assisted breast-conserving surgery showed no increases in local or distant recurrence and patient satisfaction was high. Video-assisted breast-conserving surgery appears useful for local treatment of breast cancer.

No significant financial relationships to disclose.

Expression of a transgene encoding mutant p193/CUL7 preserves cardiac function and limits infarct expansion after myocardial infarction

BACKGROUND

Transgenic mice expressing the dominant interfering p193 protein in cardiomyocytes (MHC-1152stop mice) exhibit an induction of cell cycle activity and altered remodelling after experimental myocardial infarction (MI).

OBJECTIVE

To determine whether the altered remodelling results in improved cardiac function in the MHC-1152stop mice after MI, as compared with non-transgenic mice.

METHODS

MHC-1152stop mice and non-transgenic littermates were subjected to experimental MI via permanent occlusion of the coronary artery. Infarct size was determined at 24 h and at 4 weeks after MI, and left ventricular pressure-volume measurements were performed at 4 weeks after MI in infarcted and sham-operated animals.

RESULTS

Infarct size in MHC-1152stop mice and non-transgenic littermates was not statistically different at 24 h after MI, as measured by tetrazolium staining. Morphometric analysis showed that infarct scar expansion at 4 weeks after MI was reduced by 10% in the MHC-1152stop mice (p<0.05). No differences in cardiac function were detected between sham-operated MHC-1152stop mice and their non-transgenic littermates. However, at 4 weeks after MI, the ventricular isovolumic relaxation time constant (tau) was decreased by 19% (p<0.05), and the slope of the dP/dt(max)-EDV relationship was increased 99% (p<0.05), in infarcted MHC-1152stop mice as compared with infarcted non-transgenic littermates.

CONCLUSION

Expression of the dominant interfering p193 transgene results in a decrease in infarct scar expansion and preservation of myocardial function at 4 weeks after MI. Antagonism of p193 activity may represent an important strategy for the treatment of MI.

Calcium pyrophosphate dehydrate crystal deposition in the ligamentum flavum of the cervical spine: histopathological and immunohistochemical findings

OBJECTIVE

To investigate the histopathological and immunohistochemical properties of degenerative changes in the ligamentum flavum of the cervical spine with calcium crystal deposition.

METHODS

Sections of the calcified ligamentum flavum harvested from 26 patients who required cervical decompression were examined by scanning electron microscopy (SEM), energy dispersive X-ray microanalysis, immunohistochemical staining [for transforming growth factor (TGF)-Beta, vascular endothelial growth factor (VEGF), Sox9, and Msx2] and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labelling (TUNEL) method (for cell apoptosis).

RESULTS

Energy dispersive x-ray microanalysis and SEM confirmed the deposited calcium to be calcium pyrophosphate dihydrate (CPPD) crystals. The calcified ligamentum flavum showed disorganisation of the elastic fibre bundles together with increased collagen fibrils in the matrix. Abundant hypertrophic chondrocytes were noted around the calcified lesions, which were strongly immunoreactive to TGF-Beta and VEGF. Staining for Sox9 was positive in metaplastic chondrocytes but negative in hypertrophic chondrocytes. Both chondrocytes and mesenchymal cells were positive for Msx2. TUNEL-positive hypertrophic chondrocytes were significantly more noticeable in nodular than diffusely scattered type of CPPD deposition.

CONCLUSIONS

Calcium crystal deposition in the cervical ligamentum flavum seems to progress with reduction in elastic fibres, increase in collagen fibrils in the matrix, and migration of metaplastic hypertrophic chondrocytes, whose differentiation is controlled by cytokines and transcriptional factors, and potentially regulate crystal formation. The presence of abundant TUNEL-positive hypertrophic chondrocytes around CPPD deposition suggests that materials from apoptotic cells play some role in crystal deposition.