Microstructural Characterization of Foam Formed by a Hydroxy Group-Containing Amino Acid Surfactant Using Small-Angle Neutron Scattering.

Small-angle neutron scattering, which has not been extensively utilized for foam characterization, can provide important insights into the microstructure of surfactant-stabilized foam. Small-angle neutron scattering in combination with several other techniques was herein employed to determine the microstructure of foams stabilized by hydroxy group-containing (C12-EtOH-ßAla) and hydroxy group-free (C12-Me-ßAla) surfactants of the amino acid type. Hydroxy group introduction at the amide nitrogen had no effect on the foam film thickness (∼26 nm in both cases) but increased the foam stability and suppressed draining, as hydrogen bonding between hydroxy groups and carboxylate ions increased the foam film strength. Moreover, the obtained foam films were shown to contain micelles identical to those in the bulk solution.

Cloning and expression of 1,2-alpha-mannosidase gene (fmanIB) from filamentous fungus Aspergillus oryzae: in vivo visualization of the FmanIBp-GFP fusion protein.

1,2-alpha-Mannosidase catalyzes the specific cleavage of 1,2-alpha-mannose residues from protein-linked N-glycan. In this study, a novel DNA sequence homologous to the authentic 1,2-alpha-mannosidase was cloned from a cDNA library prepared from solid-state cultured Aspergillus oryzae. The fmanIB cDNA consisted of 1530 nucleotides and encoded a protein of 510 amino acids in which all consensus motifs of the class I alpha-mannosidase were conserved. Expression of the full length of 1,2-alpha-mannosidase cDNA by the Aspergillus host, though it has rarely been done with other filamentous-fungal mannosidase, was successful with fmanIB and caused an increase in both intracellular and extracellular mannosidase activity. The expressed protein (FmanIBp) specifically hydrolyzed 1,2-alpha-mannobiose with maximal activity at a pH of 5.5 and a temperature of 45 degrees C. With Man(9)GlcNAc(2) as the substrate, Man(5)GlcNAc(2) finally accumulated while hydrolysis of the 1,2-alpha-mannose residue of the middle branch was rate-limiting. To examine the intracellular localization of the enzyme, a chimeric protein of FmanIBp with green fluorescent protein was constructed. It showed a dotted fluorescence pattern in the mycelia of Aspergillus, indicative of the localization in intracellular vesicles. Based on these enzymatic and microscopic results, we estimated that FmanIBp is a fungal substitute for the mammalian Golgi 1,2-alpha-mannosidase isozyme IB. This and our previous report on the presence of another ER-type mannosidase in A. oryzae (Yoshida et al., 2000) support the notion that the filamentous fungus has similar steps of N-linked glycochain trimming to those in mammalian cells.

Stenosis of the bicuspid aortic valve with systemic lupus erythematosus.

We herein present a rare case of severe aortic valve stenosis with a bicuspid valve in a patient with systemic lupus erythematosus. The symptoms resulted from aortic valve stenosis, such as chest pain, dyspnea and syncope, which subsided after the insertion of an intra-aortic balloon pump. Thereafter, a calcified bicuspid aortic valve was successfully replaced with a mechanical valve. The pathological findings of the resected valve included irregular fibrotic thickening and marked calcification without any vegetation or thrombus formation. The efficacy of an intra-aortic balloon pump for the relief of symptoms associated with severe aortic valve stenosis indicates its usefulness for such critically ill patients prior to undergoing valvular surgery.

Comparison of limited and full sternotomy in aortic valve replacement.

OBJECTIVE: The practice of minimally invasive valve surgery remains controversial. The aim of this study was to evaluate the technical feasibility and postoperative course of aortic valve replacement through limited upper sternotomy compared to conventional full sternotomy. METHODS: From May 1998 to August 2000, we performed 24 cases of isolated aortic valve replacements through the limited upper sternotomy approach (group M). During the same period, 18 patients received isolated aortic valve replacements through the conventional full sternotomy approach (group C). Operation duration, postoperative course and laboratory data were compared between the two groups. RESULTS: All patients received a valve replacement with a prosthetic valve. There was no significant difference between the two groups in mean aortic cross-clamping time, mean cardiopulmonary bypass time or mean operation duration (skin to skin). No patient required blood transfusion. Patients in the group M were extubated earlier, with less postoperative blood loss and discharged earlier after the operation than those in group C. On the first postoperative day, the peak level of lactic acid dehydrogenease was significantly lower in the group M than those in group C. CONCLUSION: Limited upper sternotomy for aortic valve replacement resulted in shorter operation duration and minimized operative risks for the patients. We believe this method brings not only cosmetic benefits but also improved postoperative course.

Lymph node metastasis, recurrence, and prognosis in small peripheral lung adenocarcinoma. Analysis based on replacement.

OBJECTIVE: We studied clinical and pathological features of small peripheral adenocarcinoma of the lung, focusing on tumor typing based on Noguchi's classification of small adenocarcinoma and determining whether these tumors grew by replacing alveolar lining cells. METHODS: Subjects were 51 patients with small peripheral adenocarcinoma 2 cm or less in diameter resected between 1994 and 2001. Mediastinal and hilar lymph node dissection was done in 37 (72.5%). Patients were divided into 2 groups by replacement or nonreplacement tumors. We compared patient profiles, lymph node involvement, and recurrence and survival patterns. RESULTS: No significant difference was seen between groups in mean age, surgical procedure, or primary tumor location. Women predominated in replacement tumors at 71% vs 41%, p = 0.04. The incidence of lymph node metastasis at 40% vs 4.5%, p = 0.007 and distant metastasis at 47% vs 2.9%, p < 0.001 was significantly higher in nonreplacement than replacement tumors. Replacements tumor thus showed significantly better disease-free survival at 95% vs 53%, p < 0.001, and overall 3-year survival at 95.4% vs 62.7% than did nonreplacement tumors. CONCLUSION: We found distant metastasis and lymph node involvement to be more frequent in nonreplacement than replacement small peripheral adenocarcinoma, on suggesting that pretreatment tumor typing and accurate nodal status determination are essential to improve disease staging.