Revealing the Velocity Uncertainties of a Levitated Particle in the Quantum Ground State.

We demonstrate time-of-flight measurements for an ultracold levitated nanoparticle and reveal its velocity for the translational motion brought to the quantum ground state. We discover that the velocity distributions obtained with repeated release-and-recapture measurements are significantly broadened via librational motions of the nanoparticle. Under feedback cooling on all the librational motions, we recover the velocity distributions in reasonable agreement with an expectation from the occupation number, with approximately twice the width of the quantum limit. The strong impact of librational motions on the translational motions is understood as a result of the deviation between the libration center and the center of mass, induced by the asymmetry of the nanoparticle. Our results elucidate the importance of the control over librational motions and establish the basis for exploring quantum mechanical properties of levitated nanoparticles in terms of their velocity.

Germline transformation of the silkworm Bombyx mori L. using a piggyBac transposon-derived vector.

We have developed a system for stable germline transformation in the silkworm Bombyx mori L. using piggyBac, a transposon discovered in the lepidopteran Trichoplusia ni. The transformation constructs consist of the piggyBac inverted terminal repeats flanking a fusion of the B. mori cytoplasmic actin gene BmA3 promoter and the green fluorescent protein (GFP). A nonautonomous helper plasmid encodes the piggyBac transposase. The reporter gene construct was coinjected into preblastoderm eggs of two strains of B. mori. Approximately 2% of the individuals in the G1 broods expressed GFP. DNA analyses of GFP-positive G1 silkworms revealed that multiple independent insertions occurred frequently. The transgene was stably transferred to the next generation through normal Mendelian inheritance. The presence of the inverted terminal repeats of piggyBac and the characteristic TTAA sequence at the borders of all the analyzed inserts confirmed that transformation resulted from precise transposition events. This efficient method of stable gene transfer in a lepidopteran insect opens the way for promising basic research and biotechnological applications.

Proton magnetic resonance spectroscopy for assessment of human body composition.

BACKGROUND: The usefulness of magnetic resonance spectroscopy (MRS)-based techniques for assessment of human body composition has not been established. OBJECTIVE: We compared a proton MRS-based technique with the total body water (TBW) method to determine the usefulness of the former technique for assessment of human body composition. DESIGN: Proton magnetic resonance spectra of the chest to abdomen, abdomen to pelvis, and pelvis to thigh regions were obtained from 16 volunteers by using single, free induction decay measurement with a clinical magnetic resonance system operating at 1.5 T. The MRS-derived metabolite ratio was determined as the ratio of fat methyl and methylene proton resonance to water proton resonance. The peak areas for the chest to abdomen and the pelvis to thigh regions were normalized to an external reference (approximately 2200 g benzene) and a weighted average of the MRS-derived metabolite ratios for the 2 positions was calculated. TBW for each subject was determined by the deuterium oxide dilution technique. RESULTS: The MRS-derived metabolite ratios were significantly correlated with the ratio of body fat to lean body mass estimated by TBW. The MRS-derived metabolite ratio for the abdomen to pelvis region correlated best with the ratio of body fat to lean body mass on simple regression analyses (r = 0.918). The MRS-derived metabolite ratio for the abdomen to pelvis region and that for the pelvis to thigh region were selected for a multivariate regression model (R = 0.947, adjusted R(2) = 0.881). CONCLUSION: This MRS-based technique is sufficiently accurate for assessment of human body composition.

Asymptomatic membranous obstruction of the inferior vena cava forming intrahepatic collateral pathways.

Intrahepatic and/or extrahepatic collateral pathways result from the membranous obstruction of the inferior vena cava. These collaterals are usually insufficient to prevent Budd-Chiari syndrome. We reprot an unusual case of asymptomatic membranous obstruction of the inferior vena cava in which marked intrahepatic collateral pathways were formed. Although the inferior vena cava terminated above the orifice of the right hepatic vein, the middle and left hepatic veins were patent above the membrane, without narrowing. Blood from the inferior vena cava drained into the right atrium via the intrahepatic collaterals between the right and middle hepatic veins without resistance.

A functional magnetic resonance imaging study during sentence reading in Japanese dyslexic children.

A functional magnetic resonance imaging (fMRI) study during Japanese 'kana' readings was performed on Japanese dyslexic children. Five dyslexic children (aged 9-12 years) and five healthy children (aged 9-11 years) were investigated. The fMRI examination was performed by getting these children to read sentences constructed from Japanese phonograms, 'kana', compared with staring at meaningless figures as a control task. All control subjects showed activation of the left middle temporal gyrus. In the dyslexic children, the activation of the middle temporal gyrus was rather vague. However, other distinctively activated regions were detected as follows: the bilateral occipital cortex in two dyslexics, the inferior part of the frontal regions in two other dyslexics, and both the bilateral occipital cortex and the inferior part of precentral gyrus in the remaining one. These results indicate compensatory management processes for the unskilled reading ability of dyslexic children. The present results were similar to previous ones for adult dyslexia with the Roman alphabet, and suggest that brain malfunction in dyslexia during the task of reading must be common despite differences in languages.

Technical note: dynamic analysis of the pharynx during swallowing using Turbo-FLASH magnetic resonance imaging combined with an oral positive contrast agent--a preliminary study.

Serial images of the swallowing motions of 10 healthy volunteers were taken using the Turbo-fast low angle shot (FLASH) magnetic resonance (MR) imaging sequence, while the subject swallowed an oral contrast agent containing ferric ammonium citrate. In all cases, the flow of the contrast agent and the motion of the organs in the oral cavity and the pharynx during swallowing could be observed. High-speed MR imaging combined with an oral positive contrast agent has the potential to evaluate accurately swallowing motion.

Intraosseous pneumatocyst of the scapula.

Intraosseous pneumatocyst is a gas-containing cyst-like lesion that occurs most frequently in the ilium, sacrum or vertebrae. We present a case involving the left scapula that was found incidentally on CT. To our knowledge, intraosseous pneumatocyst of the scapula has not been previously reported.

Time-course changes of contrast enhancement in iron colloid enhanced MRI in patients with hepatocellular carcinoma.

Time-course changes in contrast enhancement of chondroitin sulphate iron colloid (CSIC), an MR contrast agent, were determined in 12 patients with 20 lesions of classical hepatocellular carcinoma (HCC). Spin echo T1 weighted (T1WI) and T2 weighted images (T2WI) were obtained before administration of CSIC and 1, 6 and 24 h after injection. The signal-to-noise ratio (SNR) in the tumour region and the liver and the tumour-to-liver contrast-to-noise ratio (CNR) were calculated, and time-course changes of these ratios were determined. SNRs for tumour before the administration of contrast medium did not differ significantly from SNRs after administration on T1WI or T2WI. SNRs for the liver on both T1WI and T2WI were significantly lower at each time point after administration than before administration. The tumour-to-liver CNRs for both T1WI and T2WI were significantly higher after administration than before administration. The maximum CNR was observed 6 h after administration on both T1WI and T2WI. The contrast enhancement was maintained for at least 24 h, with a peak at 6 h after administration. The prolonged enhancement obtained with CSIC has extended the time during which effective contrast is maintained.

MRI appearances of fascioliasis complicating liver iron overload.

A case of hepatic fascioliasis with an unusual appearance on MRI due to liver iron overload is presented. The diagnosis of fascioliasis was based on positive serological tests and the presence of eggs in the bile. Hepatic lesions of fascioliasis exhibited hyperintense signals on T1 weighted images as well as proton density and T2 weighted images. Histological study of biopsy specimens from the lesions showed central necrosis and peripheral fibrosis with inflammatory cells including eosinophils. Abundant iron deposition in hepatocytes and Kupffer cells was found in specimens from the surrounding liver. These findings suggested that this appearance on MR images was probably due to a decrease in signal intensity in surrounding liver.

Measurement of cerebral mean transit time by dynamic susceptibility contrast magnetic resonance imaging.

OBJECTIVE: To determine whether direct measurement of mean transit time from pixels over in-plane vessels on high spatial resolution echo planar imaging is a reliable method for quantitative assessment of cerebral circulation. METHODS AND MATERIALS: Dynamic susceptibility contrast studies were performed using high spatial resolution echo planar imaging (echo time, 60 ms; field of view, 256 x 192-270 x 203 mm; matrix size, 256 x 192; slice thickness, 4 mm) in ten healthy subjects. Forty sequential measurements of five images between the level of the middle cerebral arteries and that of the centrum semiovale were acquired every 1.5 s before, during, and after intravenous injection of 0.12 mmol/kg of gadopentetate dimeglumine. Mean transit times were calculated from the results of gamma variate fitting to the measured deltaR2* data of the middle cerebral arteries, cerebral cortex and white matter. RESULTS: The calculated true mean transit times for cerebral cortex and white matter varied greatly among individuals and from side to side even in a given individual. The fitness of regression models for the deltaR2* curves of the middle cerebral arteries was significantly lower than those for cerebral cortex and white matter. CONCLUSION: Direct measurement of mean transit time from pixels over in-plane vessels was not sufficiently accurate for quantitative assessment of cerebral circulation, probably because the echo planar imaging we used had spatial resolution and dynamic range insufficient for determination of mean transit time for in-plane vessels.

Association of cervical SIL and HIV-1 infection among Zimbabwean women in an HIV/STI prevention study.

A cross-sectional study was conducted on women attending family planning clinics in Harare, Zimbabwe to determine the prevalence of cervical neoplasia among HIV-1 positive women relative to an HIV-1 negative control group. Five hundred and fifty four women were recruited and the prevalence of HIV-1 was 36.8%. Cervical cytology was abnormal in 25.6% of HIV-infected women compared to only 6.7% HIV-1 seronegative women. Cervical neoplasia was significantly associated with HIV infection (chi(2)=42.4, P<0.001). Cellular changes typical of HPV infection (koilocytocis) were recorded in 6.4% of HIV infected women compared with 1.7% of HIV-1-uninfected women (chi(2)=8.43, P=0.004). HIV-1-positive women had twice the risk of having abnormal cervical cells than HIV-negative women (relative risk 2.47, odds ratio 10.14, P<0.001). Therefore the introduction of national cervical screening programme in HIV-1 endemic countries like Zimbabwe where the highest burden of pre-malignant lesions is among HIV-1-infected women needs careful planning because these women have other competing health needs including high rates of opportunistic infections.

Evaluation of the mechanical destructive force in the stomach of dog.

Orally administered dosage forms receive a destructive force in the gastrointestinal (GI) tract due to peristalsis. In this study, the destructive force was measured with a 'destructive force-dependent release system' (DDRS). DDRS is a press-coated tablet with an extremely brittle outer layer composed of highly hydrophobic Teflon(R) powder, which is molded with a weak compression force. Teflon(R) powder forms a porous but water-impermeable layer around the core tablet. A marker drug contained in the core tablet is released only when the tablet receives a force larger than its pre-determined crushing strength. A comparison of the physiological conditions in the GI tract of dogs with those of humans, including the destructive force against tablets in the stomach, helps us to understand their difference in bioavailability of oral dosage forms. With DDRS, it is possible to evaluate the destructive force of both human and dog stomach using the same method. Therefore, the destructive force data from human and dog can be directly compared. The destructive force in the dog stomach was evaluated to be 3.2 N, which was considerably stronger than that of humans.

A unique dosage form to evaluate the mechanical destructive force in the gastrointestinal tract.

The purpose of this study was to prepare tablets that could evaluate the destructive force in the gastrointestinal (GI) tract. Many factors are known to affect in vivo drug release from oral dosage forms. There is still relatively little information on the mechanical destructive force in the GI tract. Press-coated tablets with an extremely brittle outer layer were developed using a unique, highly hydrophobic Teflon powder that could be shaped with weak compression force. A marker drug contained in the tablets was released only when the tablets received a force larger than its predetermined crushing strength. We referred to this type of tablet as a 'destructive force dependent release system' (DDRS). A total of nine healthy, male subjects were orally administered the tablets under fed and/or fasting conditions. Tablets with a predetermined crushing strength of 1.50 N were crushed by all of the four subjects who took them under fed conditions and two of the five subjects under fasting conditions. Tablets with a crushing strength of 1.89 N were crushed by two of the six subjects who took them under fed conditions and none of the five subjects under fasting conditions. The range of mechanical destructive force in the human stomach was obtained.

Comparison of various techniques of iron oxide-enhanced breath-hold MR imaging of hepatocellular carcinoma.

The purpose of our study is to compare qualitatively and quantitatively the abilities of various superparamagnetic iron oxide (SPIO)-enhanced breath-hold magnetic resonance imaging (MRI) techniques to detect hepatocellular carcinoma (HCC). Eight patients with HCCs were imaged. The images were obtained with conventional T2-weighted spin-echo imaging (CSE), half-Fourier single-shot turbo spin-echo (HASTE), single-shot gradient-echo type echo planar imaging (GE-EPI), and single-shot spin-echo type echo planar imaging (SE-EPI) before and after SPIO administration. The liver signal-to-noise ratios (SNRs) in CSE and each EPI sequence were significantly decreased after SPIO administration. GE-EPI had the highest decrease ratio (DR) of liver SNR, followed by SE-EPI (TE=98), SE-EPI (TE=28), CSE, and HASTE in this order. The relative contrasts with GE-EPI and SE-EPI (TE=98) were significantly higher than that with CSE after SPIO administration. On receiver operating characteristic (ROC) analysis, diagnostic accuracy did not differ significantly among the pulse sequences after SPIO administration. GE-EPI and SE-EPI (longer TE) were useful for SPIO-enhanced breath-hold MRI performed to detect HCC.

Basic analysis of dynamic study in cases of hepatocellular carcinoma using inversion recovery snap shot FLASH MR imaging with Gd-DTPA.

Twenty patients with hepatocellular carcinoma were studied by dynamic sequential inversion recovery snap shot fast low angle shot (FLASH) imaging after the bolus injection of various amounts of Gd-DTPA. We determined the optimal dose of Gd-DTPA for depicting tumors as early marked enhancement and compared the method with dynamic CT by matching data acquisition time. The optimal dose was estimated to be 0.1 mmol/kg. Compared with dynamic CT, dynamic MRI showed rapid short-term enhancement in the early phase, while the contrast enhancement in the late phase lasted longer and was stronger than that of CT.

Chondroitin sulfate iron colloid-enhanced MR imaging in patients with hepatocellular carcinoma. Comparison with CT during arterial portography.

Chondroitin sulfate iron colloid (CSIC) was used as an MR contrast agent for the detection of hepatocellular carcinoma (HCC). The findings of 25 surgically confirmed HCCs in 19 patients were retrospectively analyzed. T1-, T2- and proton density-weighted spin echo MR images were obtained before and after i.v. injection of 23.6 microM Fe/kg of CSIC. Unenhanced and CSIC-enhanced MR images and images obtained by CT during arterial portography (CT-AP) were correlated with surgical pathology findings. The sensitivities of CSIC-enhanced and unenhanced MR imaging, and CT-AP were 92%, 80%, and 88%, respectively. No significant differences were noted. Portal flow abnormalities demonstrated by CT-AP did not affect the detection of HCC by CSIC-enhanced MR imaging. CSIC-enhancement at MR imaging was a disadvantage in the detection of lesions less than 1 cm in diameter. CSIC-enhanced MR imaging is a supplemental method for the detection of HCC.

Correlation between chondroitin sulfate iron colloid-enhanced MR imaging and the histological grade of hepatocellular carcinoma.

The association between contrast enhancement by chondroitin sulfate iron colloid (CSIC) and the histological grade of hepatocellular carcinoma (HCC) was evaluated in 24 patients diagnosed by histological examination of surgical specimens (26 nodules: 11 well-differentiated and 15 poorly-moderately-differentiated nodules). In the well-differentiated HCC nodules, the tumor-liver contrast to noise ratio (CNR) was not significantly increased after i.v. CSIC injection on both T1-weighted and T2-weighted images. In the moderately-poorly-differentiated HCC, CNR was significantly increased after CSIC administration on both T1-weighted and T2-weighted images (p < 0.01). MR imaging using CSIC may be useful for diagnosing the degree of HCC differentiation.

Usefulness of MR angiography in detection of persistent trigeminal arteries.

OBJECTIVES: To examine the usefulness of magnetic resonance angiography (MRA) in detection of persistent trigeminal arteries (PTA). MATERIAL AND METHODS: 3D-time-of-flight (TOF)-MRA images obtained from 1100 patients (798 males and 302 females aged 6-75 years with a mean of 55 years) at our and related institutions were examined retrospectively for PTA. The course of the PTA was classified into the posteromedial type and posterolateral type. Charts of the patients were also examined retrospectively for clinical symptoms related to PTA. RESULTS: PTA was observed in 5 (0.45%) of the 1100 patients, and no aneurysm or arteriovenous malformation was noted in any of these 5 patients. PTA was the posteromedial type in 2 and posterolateral type in 3. PTA was possibly related with clinical symptoms in only 1 patient with oculomotor paresis. CONCLUSION: MRA is useful for non-invasive screening for PTA.

Cerebral metabolic impairment in patients with obstructive sleep apnoea: an independent association of obstructive sleep apnoea with white matter change.

OBJECTIVES: To determine the relation between severity of obstructive sleep apnoea (OSA) and degree of cerebral metabolic impairment. METHODS: Fifty five patients with habitual snoring and excessive daytime sleepiness underwent standard overnight polysomnography and magnetic resonance spectroscopy separately. Proton MR spectra were measured with two dimensional chemical shift imaging (repetition time; 1500 ms, echo time; 135 ms). Severity of cerebral metabolic impairment was assessed by the N-acetylaspartate (NAA)/choline ratios for the cerebral cortex and white matter. Severity of OSA was assessed by the apnoea-hypopnoea index (AHI) and the minimum value of peripheral oxyhaemoglobin saturation. All patients were evaluated for the presence or absence of comobidities including hypertension, cardiac disease, diabetes mellitus, and hyperlipidaemia. Univariate analysis of variance (ANOVA) and mulitple linear regression analysis were used for statistical analyses. RESULTS: Univariate ANOVA disclosed significant effects of AHI, age, and the presence or absence of hypertension on the NAA/choline ratio for cerebral white matter (p=0.011, p=0.028, p=0.0496, respectively). The AHI had a significant negative association with the NAA/choline ratio for cerebral white matter, independent of age and the presence or absence of cardiac disease, in the final multivariate regression model (standardised partial regression coefficient=-0.417, p<0.001). No significant relation was found between severity of OSA and the NAA/choline ratio for the cerebral cortex. Age alone had a significant effect on the NAA/choline ratio for the cerebral cortex on univariate ANOVA (p<0.001) and a significant negative association with the NAA/choline ratio for the cerebral cortex in the regression model (r=-0.552, p<0.001). CONCLUSIONS: A significant relation exists between AHI and the degree of metabolic impairment in cerebral white matter in patients with OSA.