One-step direct assay for mature-type adrenomedullin with monoclonal antibodies

Adrenomedullin (AM) is a potent hypotensive peptide. Plasma contains mature-type AM (m-AM), which is amidated at the carboxy terminus, and an intermediate, AM-Gly. We developed a one-step two-site IRMA specific for determining human m-AM with monoclonal antibodies. The detection limit was 0.5 pmol/L, and the working range (CV <15%) was 1-300 pmol/L. Dilution of plasma samples showed good linearity. The recovery of added AM was 91-118%. The intra- and interassay imprecision values (CVs) were 4.4-8.2% and 5.5-8.3%, respectively. The assay had no cross-reactivity with AM-Gly or other peptides similar to AM. The mean (+/- SD) plasma human m-AM concentration of 61 healthy subjects was 1.18 +/- 0.65 pmol/L. In conclusion, our IRMA makes it possible to specifically measure m-AM, using a small amount of plasma sample (0.2 mL) by a one-step overnight assay without prior extraction. Our simplified method would be suitable for clinical studies on AM, especially when large numbers of samples must be processed.     

Excitations bound to a vortex line in layered superconductors

Using Bogoliubov-de Gennes equation, we study quasiparticle excitations in layered superconductors in the presence of a straight vortex line which is parallel to the layers. The lowest bound state is shown to have energy eigenvalue of the order of magnitude , the energy gap, in contrast to the corresponding value ²/E_F when the line is perpendicular to the layers.     

Acidophilic xylanase from Aureobasidium pullulans: efficient expression and secretion in Pichia pastoris and mutational analysis

A yeast-like fungus Aureobasidium pullulans var. melanigenum strain ATCC 20524 produces an extracellular acidophilic endo-1,4-beta-xylanase with an optimum pH of 2.0 [Ohta et al., J. Biosci. Bioeng., 92, 262-270 (2001)]. The xynI cDNA encoding the precursor protein (XynI) was expressed in the methylotrophic yeast Pichia pastoris under the control of the alcohol oxidase I gene promoter. The 34 amino acid prepro-signal peptide of the A. pullulans XynI directed the efficient secretion of 178 mg of active xylanase per liter of the culture medium. The secretion level of the xylanase with its own signal peptide was comparable to that of the mature protein fused to the prepro leader from Saccharomyces cerevisiae alpha-mating factor and twofold higher than that of the mature protein fused to the pre-type signal peptide from P. pastoris acid phosphatase. The N-terminal amino acid sequence and the apparent M(r) of 24 kDa of the secreted recombinant protein indicated the native-like processing of the A. pullulans XynI signal sequence in P. pastoris. The three-dimensional model and mutational analysis of the xynI gene product showed that Asp-73 and Glu-157 residues located at the upper and lower edges of the active site cleft, respectively, play a significant role in its low pH optimum.     

Successful high-dose chemotherapy combined with autologous bone marrow transplantation in a case of refractory follicular lymphoma

This study investigated the association between two demographic and two psychological variables and treatment retention for 65 perinatal substance abusers. Subjects who lived in the community while attending day treatment were 6.125 times more likely to drp out than subjects who lived in a program-operated shelter (p < .0001). An interaction was found for pregnancy status and antisocial personality disorder (p < .0478). Subjects who were both pregnant and antisocial were 4.876 times more likely to remain in treatment than those who were neither pregnant nor antisocial. Degree of "treatment resistance," measured by the MMPI Negative Treatment Indicators (TRT) Scale, did not predict dropout. These findings indicate that supportive housing can play an important role in preventing dropout for perinatal substance abusers. Additionally, pregnancy may present a "window" of opportunity for treating a hard to reach population, drug abusing women with comorbid ASP.     

Signet-ring cell carcinoma of the ileum: report of a case and review of the Japanese literature

We report herein the extremely unusual case of a 71-year-old woman with signet-ring cell carcinoma of the ileum. She originally presented with a 6-month history of intermittent nausea and abdominal distention, but initial examinations, including gastrointestinal fiberscopy, ultrasonography, and computed tomography (CT) scan, failed to reveal any cause of her symptoms. A barium-enema study performed 11 months after her initial visit demonstrated a narrow portion of the terminal ileum. An ileocecal resection was subsequently performed, and an epigastric subcutaneous tumor was simultaneously excised. The specimen contained a tumor with a stenotic lumen resembling a "lead pipe", an ulcerative portion, and mucosa with a granular appearance adjoining its proximal site. Many small aphthous lesions with IIa + IIc appearance were seen in the apparently normal mucosa. Histopathological examination confirmed a diagnosis of signet-ring cell carcinoma. The small aphthous lesions seemed to be metastases spread via the lymphatic vessels. Our review of the medical literature revealed three cases of signet-ring cell carcinoma of the jejunum; however, this is the first reported case of signet-ring cell carcinoma of the ileum.     

Analytical study of nuclear-coupled density-wave instability in a natural circulation pressure tube type boiling water reactor

An analytical model has been developed to study the nuclear-coupled density-wave instability in the Indian advanced heavy water reactor (AHWR) which is a natural circulation pressure tube type boiling water reactor. The model considers a point kinetics model for the neutron dynamics and a lumped parameter model for the fuel thermal dynamics along with the conservation equations of mass, momentum and energy and equation of state for the coolant. In addition, to study the effect of neutron interactions between different parts of the core, the model considers a coupled multipoint kinetics equation in place of simple point kinetics equation. Linear stability theory was applied to reveal the instability of in-phase and out-of-phase modes in the boiling channels of the AHWR. The results indicate that the stability behavior of the reactor is greatly influenced by the void reactivity coefficient, fuel time constant, radial power distribution and channel inlet orificing. The delayed neutrons were found to have a strong influence on the Type I and Type II instabilities observed at low and high channel powers, respectively. Also, it was found that the coupled multipoint kinetics model and the modal point kinetics model predict the same threshold power for out-of-phase instability if the coupling coefficient in the former model is half the eigen value separation between the fundamental and the first harmonic mode in the latter model. Decay ratio maps were predicted considering various operating parameters of the reactor, which are useful for its design.