Changes in apparent diffusion coefficients in the normal uterus during different phases of the menstrual cycle

This study investigated the apparent diffusion coefficients (ADCs) of the uterine zonal structures (myometrium, endometrium and junctional zone) among reproductive women, and their changes during the menstrual cycle. Magnetic resonance (MR) images of seven healthy females (aged 24-31 years) were obtained during the periovulatory, luteal and menstrual phases. Diffusion-weighted imaging (DWI) was performed with a single-shot echo-planar imaging (EPI) sequence in the midsagittal plane of the uterus using three b-values (b = 0, 500 or 1000 s mm(-2)). The ADC values of the three uterine zonal structures were measured on an ADC map by placing two regions of interest (ROI) on the corresponding zonal structures. The average changes of ADC values (intra-individual ADC value variation) over three menstrual phases were 0.41 x 10(-3) mm(2) s(-1) (range, 0.08-0.91) for myometrium, 0.55 x 10(-3) mm(2) s(-1) (0.35-0.84) for endometrium, and 0.40 x 10(-3) mm(2) s(-1) (0.18-0.59) for the junctional zone. The ADC values for myometrium and endometrium were lower in the menstrual phase, although there was some overlap of individual values. Interindividual variation in ADC value for a given zone or phase ranged from 0.48 x 10(-3) mm(2) s(-1) to 0.85 x 10(-3) mm(2) s(-1). Intermeasurement variation between the two ROIs ranged from 0 to 0.48 x 10(-3) mm(2) s(-1) per measurement. The magnitude of these variations was comparable to reported differences between malignant and non-malignant tissues. These preliminary results, from a small number of subjects, suggest that the menstrual cycle and individual variation in pre-menopausal women should be considered when interpreting the ADC values of uterine structures.

Purification and Characterization of O-Methyltransferase I Involved in Conversion of Demethylsterigmatocystin to Sterigmatocystin and of Dihydrodemethylsterigmatocystin to Dihydrosterigmatocystin during Aflatoxin Biosynthesis

O-Methyltransferase I, which catalyzes conversions both of demethylsterigmatocystin (DMST) to sterigmatocystin (ST) and of dihydrodemethylsterigmatocystin (DHDMST) to dihydrosterigmatocystin (DHST) during aflatoxin biosynthesis, was purified to apparent homogeneity from the cytosol fraction of the mycelia of Aspergillus parasiticus NIAH-26 through the following chromatography series: phenyl-Sepharose, DEAE-Sepharose, phenyl-Sepharose, Sephacryl S-300, and Matrex gel Green A. The apparent molecular mass was estimated at 150 kDa based on Sephacryl S-300 gel filtration chromatography, and the denaturing molecular mass was 43 kDa based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The pI of the enzyme was 4.4, and the optimal pH for activity was broad, from 6.5 to 9.0. In competition experiments using the purified enzyme, the formation of ST from DMST was suppressed when DHDMST was added to the reaction mixture and DHST was newly formed. These results indicate that DMST and DHDMST commonly serve as substrates for the enzyme. The K(m) of the enzyme for DMST was 0.94 muM, and that for DHDMST was 2.5 muM. Interestingly, MT-I kinetics deviated substantially from standard Michaelis-Menten kinetics, demonstrating substrate inhibition at a higher substrate concentration.

[Acute pulmonary thromboembolism in polysplenia syndrome]

We present a case of azygos continuation of the inferior vena cava, combined with polysplenia syndrome in a 72-year-old woman who presented with circulatory collapse due to acute pulmonary thromboembolism. Patients with polysplenia have multiple spleens, and their splenic function is usually normal, but this case was not. In this case, defective splenic function was associated with a high risk of fulminant bacterial infections, especially with encapsulated bacteria. The clinical features and prognosis of this entity are discussed.

Large-area imager of hydrogen leaks in fuel cells using laser-induced breakdown spectroscopy

We constructed a simple device, which utilized laser-induced breakdown spectroscopy to image H2 gas leaking from the surfaces of hydrogen fuel cells to ambient air. Nanosecond laser pulses of wavelength lambda=532 nm emitted from a neodymium-doped yttrium aluminum garnet laser were first compressed to a pulse length Deltat<1 ns using a stimulated Brillouin backscattering cell. Relay-imaging optics then focused this beam onto the H(2) leak and initiated the breakdown plasma. The Balmer-alpha (H-alpha) emission that emerged from this was collected with a 2-m-long macrolens assembly with a 90-mm-diameter image area, which covered a solid angle of approximately 1 x 10(-3)pi steradians seen from the plasma. The H-alpha light was isolated by two 100-mm-diameter interference filters with a 2 nm bandpass, and imaged by a thermoelectrically cooled charge-coupled device camera. By scanning the position of the laser focus, the spatial distribution of H2 gas over a 90-mm-diameter area was photographed with a spatial resolution of < or = 5 mm. Photoionization of the water vapor in the air caused a strong H-alpha background. By using pure N2 as a buffer gas, H2 leaks with rates of <1 cc/min were imaged. We also studied the possibilities of detecting He, Ne, or Xe gas leaks.

Normal pituitary stalk: high-resolution MR imaging at 3T

BACKGROUND AND PURPOSE

Knowing the normal imaging appearance of the pituitary stalk is important for the diagnosis of pituitary infundibular lesions, and more accurate assessment of the stalk may be possible at 3T than at 1.5T. Our purpose was to evaluate the normal pituitary stalk by use of high-resolution MR imaging at 3T.

MATERIALS AND METHODS

Sagittal MPRAGE images and high-resolution oblique-axial T2-weighted images of the pituitary stalk were acquired in 29 healthy volunteers (16 men and 13 women; mean age, 28 years; age range, 21-43 years) at 3T. The diameter and length of the pituitary stalk and the depth of the infundibular recess were measured. Signal intensity of the stalk was visually evaluated on T2-weighted images.

RESULTS

The AP and transverse diameters of the pituitary stalk were 2.32 +/- 0.39 mm and 2.16 +/- 0.37 mm at the pituitary insertion, respectively, and 3.25 +/- 0.43 mm and 3.35 +/- 0.44 mm at the level of the optic chiasm. No significant differences were observed between the AP and transverse diameters at each level. The length of the stalk was 5.91 +/- 1.24 mm, and the depth of the infundibular recess was 4.69 +/- 0.87 mm. The stalk showed central hyperintensity with a peripheral rim of isointensity in 20 subjects (69%) and homogeneous isointensity in 9 subjects (31%).

CONCLUSIONS

The data of the current study can serve as standard measurements of the normal pituitary stalk. The central hyperintensity and peripheral rim may represent the infundibular stem and pars tuberalis, respectively.

Predicting the chance of weaning dysphagic stroke patients from enteral nutrition: a multivariate logistic modelling study

AIM

The aim of this article was to develop a simple predictive model of dysphagia outcome for stroke patients. The study enrolled patients recovering from first-ever stroke (supratentorial lesions) staying in a long-term rehabilitation hospital. On admission, all patients were being fed via nasogastric or percutaneous endoscopic gastrostomy (PEG) tube.

METHODS

Functional Independence Measure (FIMTM) scores were assessed on admission. FIM-motor and cognition score, age, days after onset on admission were set as explanatory variables. Target criteria were defined as dichotomous categories; completely oral feeding or any need for nutrition via tube feeding. Multivariate logistic analysis was performed on these data.

RESULTS

Thirty patients were enrolled: age range was 50-94 (median 75) years; FIM-motor scores spanned 13 to 17 (median 13), FIM-cognition scores spanned 5 to 19 (median 9); and days from stroke onset to transfer to long-term rehabilitation care ranged from 15 to 64 (median 43.5) days. Of these patients, 12 were weaned back to oral feeding and 18 were not. Multivariate logistic regression modelling was successful on these data (P=0.0003, R2=0.518; Logit=0.770xFIM-motor+0.089xFIM-cognition 0.070xdays after onset 0.255xage+10.222). Estimated probability for return to oral feeding is nearly 10% when logit equals -2, 50% when logit equals 0, nearly 90% when logit equals 2.

CONCLUSIONS

A logit formula factoring in age, FIM scores, and days after stroke onset can readily predict oral feeding outcome. Further studies are needed to assess external validation to establish wide clinical applicability of this prediction model.

Frustration-induced valence bond crystal and its melting in Mo3Sb7

(121/123)Sb nuclear quadrupole resonance and muon spin relaxation experiments of Mo_3Sb_7 revealed symmetry breakdown to a nonmagnetic state below the transition recently found at T_S approximately 50 K. The transition is characterized by a distinct lattice dynamics suggested from narrowing of nuclear fields. We point out that the Mo sublattice is a unique three-dimensional frustrated lattice where nearest-neighbor and next-nearest-neighbor antiferromagnetic interactions compete, and propose that tetragonal distortion to release the frustration stabilizes long-range order of spin-singlet dimers, i.e., valence bond crystal, which is thermally excited to the dynamic state with cubic symmetry.

A ketolide antibiotic, telithromycin, inhibits vascular adrenergic neurotransmission in the rat mesenteric vascular bed

BACKGROUND AND PURPOSE

A ketolide antibiotic, telithromycin, has side effects including temporary loss of consciousness in clinical use, but the underlying mechanisms remain unclear. This study investigated the effects of telithromycin on perivascular nerve function in rat mesenteric arteries, in comparison with those of macrolide (erythromycin and clarithromycin) and new quinolone antibiotics (levofloxacin and gatifloxacin).

EXPERIMENTAL APPROACH

In vitro, vascular responses and release of noradrenaline induced by periarterial nerve stimulation (PNS) of rat perfused mesenteric vascular beds were measured in the presence of each antibiotic. In vivo blood pressure measurement was performed in Wistar rats.

KEY RESULTS

In mesenteric preparations with resting tone, telithromycin (10 nM-10 microM) markedly inhibited PNS (4-12 Hz)-induced adrenergic nerve- and exogenous noradrenaline-mediated vasoconstriction, whereas the other antibiotics slightly inhibited PNS-induced responses without affecting noradrenaline-induced responses. Telithromycin significantly reduced PNS (12 Hz)-evoked noradrenaline release in the perfusate. In pre-constricted preparations with or without endothelium, telithromycin (0.1 nM-10 microM) caused a concentration-dependent vasodilation. Telithromycin (10 nM) inhibited calcium-induced vasoconstriction in high KCl and calcium-free medium. None of the antibiotics used affected PNS (0.5-2 Hz)-induced calcitonin gene-related peptide (CGRP) nerve- and exogenous CGRP-mediated vasodilation. Intravenous injection of telithromycin significantly lowered blood pressure in anaesthetized rats.

CONCLUSIONS AND IMPLICATIONS

These results suggest that telithromycin causes not only strong inhibition of perivascular adrenergic neurotransmission but also a vasodilator action in mesenteric vascular beds and hypotension. It is thus possible that telithromycin increases visceral blood flow, consequently reducing cerebral blood flow and resulting in a temporary loss of consciousness.

Persistent lymphoedema in Morbihan disease: formation of perilymphatic epithelioid cell granulomas as a possible pathogenesis

Morbihan disease is a rare complication of rosacea, characterized by persistent lymphoedema on the upper half of the face, occurring during the chronic clinical course of rosacea. This refractory condition has been also designated as 'rosacea lymphoedema' and 'solid persistent facial oedema of rosacea'. We report a patient with Morbihan disease showing persistent lymphoedema on the upper half of the face accompanied by unique histological findings of striking dermal dilated lymphatics and damage of the lymphatics at the site of the adjacent epithelioid cell granulomas, with histiocytes bulging into the lymphatic lumen. The marked epithelioid cell granulomas forming around dermal lymphatic vessels with subsequent lymphatic damage and luminal obstruction by histiocytic infiltration may account for the development of lymphoedema in this patient.

Probiotic products in Canada with clinical evidence: what can gastroenterologists recommend?

Probiotics, defined as 'live microorganisms, which when administered in adequate amounts, confer a health benefit on the host', are finally becoming an option for gastroenterologists in Canada, after being available for many years in Japan, Europe and the United States of America. Unfortunately, Health Canada and the US Food and Drug Administration have not controlled the use of the term 'probiotic' or put into place United Nations and World Health Organization guidelines. The net result is that a host of products called 'probiotics' are available but are not truly probiotic. The aim of the present review was to discuss the rationale for probiotics in gastroenterology, and specifically examine which products are options for physicians in Canada, and which ones patients might be using. It is hoped that by clarifying what probiotics are, and the strengths and limitations of their use, specialists will be better placed to make recommendations on the role of these products in patient care. In due course, more clinically documented probiotics will emerge, some with therapeutic effects based on a better understanding of disease processes.

Control of fracture reduction robot using force/torque measurement

We have developed a surgical robotic system for femoral fracture reduction employing indirect traction. Indirect traction in fracture reduction is a generally used surgical method for preventing complications such as bone splits caused by high stress on bones. For traction, a patient's foot is gripped by a jig and pulled to the distal side. Indirect traction has the advantage of distributing bone stress by utilizing a strong traction force; however, this procedure does not accurately control the proper positioning of fractured fragments when a surgical robot is used. The human leg has knee and an ankle joints, and thus robotic motion presents problems in not being able to directly propagate reduction motion to a fractured femoral fragment, rendering control of bone position difficult. We propose a control method for fracture reduction robots using external force/torque measurements of the human leg to achieve precise fracture reduction. Results showed that the proposed method reduced repositioning error from 6.8 mm and 15.9 degrees to 0.7 mm and 5.3 degrees, respectively.

Novel biomedical imaging approach for detection of sentinel nodes in an experimental model of gastric cancer

BACKGROUND

The aim of this study was to validate a novel imaging system that uses ATX-S10Na(II) to detect sentinel nodes (SNs) in gastric cancer. The new technique was compared with the enhanced visualization method using indocyanine green (ICG).

METHODS

Human gastric carcinoma cells were implanted orthotopically into 50 nude rats, which were divided into two groups. In the first group (n = 25), ATX-S10Na(II) was injected subserosally into the implanted site and visualized by a fluorescence spectrolaparoscope. In the second group (n = 25), ICG was similarly injected and observed through a near-infrared laparoscope. The presence of metastatic tumour cells was determined by reverse transcriptase-polymerase chain reaction specific for human beta-actin.

RESULTS

ATX-S10Na(II) was clearly identified as a bright red colour, and was rapidly incorporated into the lymphatic system. Detection rates of SNs were 100 (95 per cent confidence interval (c.i.) 52 to 100) per cent (25 of 25) for ATX-S10Na(II) and 95 (95 per cent c.i. 40 to 100) per cent (21 of 22) for ICG. Sensitivity was 96 (95 per cent c.i. 45 to 100) and 81 (95 per cent c.i. 58 to 95) per cent respectively.

CONCLUSION

These results support the validity of the ATX-S10Na(II)-guided approach in the detection of SNs in gastric cancer in vivo.