Crossflow filtration of yeast broth cultivated in molasses

A broth of yeast cells cultivated in molasses was crossfiltered with a thin-channel module. The permeation flux gradually decreased at a constant cell concentration. The flux was much lower than that obtained for yeast broth cultivated in yeast extract, polypeptone, and dextrose (YPD) medium during the filtration. The flux did not depend on the membrane pore size (0.45 to 5 mum). The steady-state flux was one-twentieth that calculated for a cake filtration mode from the amount of cake per unit filtration area and the specific resistance of the cake measured in a dead-end filtration apparatus. The lower flux was due to small particles (most of which were less than 1 mum in diameter) in the molasses. The mehanism of crossflow filtration of broths of yeast cells cultivated in molasses was clarified by analysis of the change in flux with time and observations with scanning electron microscopy. At the initial stage of crossflow filtration the yeast cells and particles from the molasses were deposited on the membrane to form the molasses were deposited on the membrane to form a cake in a similar way to dead-end filtration. After the deposition of cells onto the membrane ceased, the fine particles from molasses formed a thin layer, which had higher resistance than the cake formed next to the membrane. The backwashing method was effective to increase the flux. The flux increased low when the pore size was 0.45 to 0.08 mum, but using larger pores of 3 to 5 mum it returned almost to the bases line. (c) 1994 John Wiley & Sons, Inc.

Ion exchange chromatography of proteins-prediction of elution curves and operating conditions. I. Theoretical considerations

A mathematical model is proposed for the elution of proteins on ion exchange columns by a linear gradient increase and stepwise increase of ionic strength in order to predict relationships between the elution characteristics (the peak position, the peak width, etc.) and the operating conditions (the flow rate, the slope of gradient, etc). This model is in principle based on the continuous-flow plate theory, in which the protein concentration and ionic strength dependent distibution coefficient between proteins and ion exchangers and zone sperading effects are taken into consideration. The advantage of this model is its simplicity since it requires only two parameters: The distribution coefficient and the number of plates. Since the distribution coefficient of proteins depends on both the protein concentration and ionic strength of the elution buffer, the number of plates should vary with time. However, it is extremely difficult to take into consideration the time-dependent number of plates. Therefore, we assume that the number of plates is constant and related to that number derived from a mass balance model which includes longitudinal dispersion and gel phase diffusion. On the basis of these assumptions, a method for determining the number of plates by the moment method is presented. Although the dependencies of the peak position and peak width on the slope of linear gradient are predictable by numerical calculations of the present model, simpler methods for prediction of these dependencies are desirable. A graphical method is proposed for prediction of the peak position. For prediction of the peak width, an asymptotic solution is derived from a quasi-steady-state model.

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.

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.

Establishment of recombinant hybrid-IgG/IgA immunoglobulin specific for Shiga toxin

Shiga toxin 1 produced by enterohaemorrhagic Escherichia coli is an AB(5) toxin that is involved in the life-threatening haemolytic-uraemic syndrome. The B subunits (Stx1B) are cell-binding subunits. We previously established mouse hybridoma cell line producing IgA and IgG monoclonal antibodies (mAbs) against Stx1B. Here, we cloned cDNAs encoding each of the heavy, light and joining (J) chains from the hybridoma cell lines by means of the 5' rapid amplification of cDNA ends (RACE) PCR method. Upon assignment of the variable regions of the heavy and light chains to known germline sequences, we found substantial somatic hypermutation in the complementarity-determining regions in both the IgA and IgG mAbs. We also established a hybrid-IgG/IgA heavy chain having variable regions of the IgG mAb by means of recombinant PCR methods. Upon transient expression of the hybrid-IgG/IgA heavy, IgG-associated light and J chains in COS-1 cells, the translated dimeric hybrid-IgG/IgA bound to immobilized Stx1B, as revealed on ELISA. The production of dimeric hybrid-IgG/IgA was revealed on immunoblot analysis. The dimeric hybrid-IgG/IgA inhibited the binding of digoxigenin-conjugated Stx1B to natural ligands (CD77) displayed on Burkitt's lymphoma cell line Ramos. These results indicate that the replacement of variable regions resulted in the production of more useful recombinant dimeric IgA against Stx1B.

P3-07-46: Accuracy of SPIO-Enhanced MR Imaging Alone for the Diagnosis of Sentinel Node Metastases in Patients with Breast Cancer

Background

Superparamagnetic iron oxide (SPIO)-enhanced MR imaging has been reported to be promising for the detection of metastases in sentinel nodes localized by CT lymphography in patients with breast cancer (Motomura, Ann Surg Oncol 2011). The current SPIO technique involves imaging before and after contrast administration. This study evaluated the accuracy of SPIO-enhanced MR imaging alone without unenhanced imaging.

Methods: This study included 120 patients with breast cancer demonstrating clinically negative nodes. Sentinel nodes were identified by CT lymphography, and MR imaging of the axilla before and 18–24 hr after interstitial administration of SPIO was performed. A node was considered non-metastatic if it showed a homogenous low signal intensity and metastatic if there was an absence of low signal intensity either in the entire node or in a focal area on SPIO-enhanced MR imaging. The diagnostic accuracy of the SPIO-enhanced imaging alone was compared with that of combined unenhanced and SPIO-enhanced imaging.

Results: The mean number of sentinel nodes identified by CT lymphography was 1.2 (range 1–3). Pathologic evaluation demonstrated that 28 (23.3%) of 120 patients showed metastasis to at least one node. One false negative result was added when the evaluation was based solely on SPIO-enhanced MR imaging. Consequently, the sensitivity decreased from 84.0% to 80.0% and the accuracy decreased from 89.2% to 88.3%, respectively, in the SPIO-enhanced MR imaging alone. However, the differences in sensitivity and accuracy between SPIO-enhanced MR imaging alone and the combined unenhanced and SPIO-enhanced imaging were not significant (McNemar's test; p=1.0). The specificity of enhanced imaging alone and that of combined unenhanced and SPIO-enhanced imaging were both 90.5%.

Conclusions: A single MR imaging examination performed after SPIO administration can be used for accurate diagnosis of sentinel node metastases, and thus reduce the time and cost of imaging.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-07-46.

MRI findings of mucoepidermoid carcinoma of the parotid gland: correlation with pathological features

OBJECTIVE

The aim of this study was to correlate the MRI appearance and pathological findings in each grade of the mucoepidermoid carcinoma (MEC) of the parotid gland.

METHODS

We reviewed surgically proven MECs of parotid glands in 20 patients. Pathologically, 5 tumours were high-grade, 3 were intermediate and 12 were low-grade. MR images were evaluated with emphasis on signal intensities on T(2) weighted images, margin characteristics and lymph node metastasis, correlating these with pathological features.

RESULTS

Among the high-grade MECs, four out of five tumours showed inhomogeneous low to intermediate signal intensity on T(2) weighted images, reflecting high cellularity. All tumours had an ill-defined margin, reflecting invasive tumour growth. Among the intermediate-grade MECs, all three tumours showed intermediate signal intensity on T(2) weighted images and two tumours had an ill-defined margin. Among the low-grade MECs, 11 of the 12 tumours had a hyperintense area on T(2) weighted images because of the existence of abundant mucin secreting cells. Seven tumours had an ill-defined margin, reflecting peritumoural inflammatory changes rather than invasive tumour growth. Lymph node metastasis was seen in three high-grade MECs.

CONCLUSION

MECs of the parotid gland show variable MRI findings reflecting their histological nature, which seems to have certain tendencies depending on the tumour grade.

Complete electric dipole response and the neutron skin in 208Pb

A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

Advantage of carbonate-versus citrate-based alkalinization on bone metabolism in moderately exercising aged male rats fed an acidogenic diet

This study aims to determine the effects of different alkaline supplementations on high protein diet-induced abnormalities affecting bone metabolism in rats which were also undergoing physical exercise of moderate intensity. Sixty elderly Sprague-Dawley rats were randomly divided into four groups of 10 rats each and treated for 16 weeks as follows: baseline control group fed normal food (C); acidic high-protein diet supplemented group (chronic acidosis, CA group), bicarbonate-based alkaline formula (Basenpulver, Named, Italy) supplemented chronic acidosis (BB-CA) and citrate-based alkaline supplement (CB-CA). Throughout the supplementation period, rats were put on a treadmill training mimicking a moderate level of exercise. In the CA group, 24-hour urinary calcium (Ca) and phosphorus (P) excretion were increased over 30 percent (p<0.05 vs normal diet controls). However serum Ca was not significantly changed. Femural and tibial BMD and BMC was significantly decreased in the CA group (p<0.05) but both alkaline supplementations prevented such phenomenon (p<0.05 vs CA), without significant difference between the two formulations although the BB-CA group showed significantly more preserved trabecular bone volume (p<0.05 vs CB-CA group). An increased level of over 50 percent of urinary Dpd observed in the CA group (p<0.001) was reverted to normal by both supplementations (p<0.001 vs CA group). The same applied to urinary net acid excretion (p<001) with BB-supplementation performing better than CB-supplementation (p<0.05). Moreover, while the latter did not modify Nterminal telopeptide value, BB-supplementation significantly normalized this parameter (p<0.05 vs CA group) which exercise and acidic protein diet had modified (p<0.01 vs control diet). Overall, the present study shows that a bicarbonate-based alkaline formula, when administered to a dose amenable to clinical use, may significantly protect bone structure in exercising aged animals to a greater extent than a quali/quantitavely similar citrate-based formula.

Use of quantitative intra-operative electrodiagnosis during partial ulnar nerve transfer to restore elbow flexion

The transfer of part of the ulnar nerve to the musculocutaneous nerve, first described by Oberlin, can restore flexion of the elbow following brachial plexus injury. In this study we evaluated the additional benefits and effectiveness of quantitative electrodiagnosis to select a donor fascicle. Eight patients who had undergone transfer of a simple fascicle of the ulnar nerve to the motor branch of the musculocutaneous nerve were evaluated. In two early patients electrodiagnosis had not been used. In the remaining six patients, however, all fascicles of the ulnar nerve were separated and electrodiagnosis was performed after stimulation with a commercially available electromyographic system. In these procedures, recording electrodes were placed in flexor carpi ulnaris and the first dorsal interosseous. A single fascicle in the flexor carpi ulnaris in which a high amplitude had been recorded was selected as a donor and transferred to the musculocutaneous nerve. In the two patients who had not undergone electrodiagnosis, the recovery of biceps proved insufficient for normal use. Conversely, in the six patients in whom quantitative electrodiagnosis was used, elbow flexion recovered to an M4 level.

Quantitative intra-operative electrodiagnosis is an effective method of selecting a favourable donor fascicle during the Oberlin procedure. Moreover, fascicles showing a high-amplitude in reading flexor carpi ulnaris are donor nerves that can restore normal elbow flexion without intrinsic loss.

Thin Film Formations of Charge Transfer Complexes with Metallic Properties by Vacuum Deposition Method

Thin films of a charge transfer complex, hepta-(tetrathiafulvalene) pentaiodide ( TTF7I5, TTF:I0-71 ), were prepared by double source evaporation of TTF and iodine. Crystalline films of TTF:I0-7i were obtained when substrate temperatures were kept between 0°C and 25°C. Orientation alignment of the crystalline films were affected by supply rate of iodine. By controlling the substrate temprature and the supply rate of iodine, highly oriented crystalline films were grown on mica substrates. It showed strong dichroism and anisotropic electrical propert ies.