High-efficiency entrapment of superoxide dismutase into cationic liposomes containing synthetic aminoglycolipid

A monofatty acid ester of glucosamine (PGlcN) was synthesized to provide liposomal membranes with a positive charge, and the trapping efficiency of negatively charged substances (superoxide dismutases, SODs) into cationic liposomes containing PGlcN or stearylamine (SA) prepared by various methods was compared to find the most efficient trapping methods. We demonstrated that cationic liposomes, which were prepared in a buffer of low ionic strength containing sorbitol by a simple hydration method, could entrap a large amount of negatively charged SODs which retained their activity, as compared with cationic liposomes prepared in a buffer of high ionic strength. We also showed a reverse-phase evaporation method entrapped a large amount of SODs. However, SODs were inactivated during the preparation; therefore, this method was not suitable to entrap the enzyme. Freeze-thaw method induced the formation of cationic liposomes which were smaller than extruded liposomes and could entrap the SODs in a buffer of low ionic strength. Dehydration-rehydration method with a buffer of low ionic strength also entrapped a large amount of SODs, indicating that the integrity of liposomes was lost in the lipid bilayer after freeze-drying and the SODs were entrapped in the reconstruction of liposomes during rehydration. These findings showed that the hydration method based on electrostatic attraction with a buffer of low ionic strength was simple and the most effective for entrapping SODs without loss of their activity.

Pore formation and translocation of melittin

Melittin, a bee venom, is a basic amphiphilic peptide, which mainly acts on the lipid matrix of membranes, lysing various cells. To elucidate the molecular mechanism, we investigated its interactions with phospholipid vesicles. The peptide formed a pore with a short lifetime in the membrane, as revealed by the release of an anionic fluorescent dye, calcein, from the liposomes. Our new double-labeling method clarified that the pore size increased with the peptide-to-lipid ratio. Upon the disintegration of the pore, a fraction of the peptides translocated across the bilayer. The pore formation was coupled with the translocation, which was proved by three fluorescence experiments recently developed by our laboratory. A novel model for the melittin pore formation was discussed in comparison with other pore-forming peptides.

Interactions of an antimicrobial peptide, magainin 2, with outer and inner membranes of Gram-negative bacteria

Magainin peptides, isolated from Xenopus skin, have broad spectra of antimicrobial activity and low toxicities to normal eukaryotic cells, thus being good candidates for therapeutic agents. The mechanism of action is considered to be the permeabilization of bacterial membranes. A number of studies using lipid vesicles have elucidated its molecular detail. However, their interactions with bacteria are not yet well understood. In this paper, we synthesized several magainin analogs with different charges (0 to +6) and hydrophobicities, and systematically studied their interactions with the outer and inner membranes of three species of Gram-negative bacteria (Escherichia coli, Acinetobacter calcoaceticus, Proteus vulgaris). The treatment of the E. coli cells with native magainin 2 (+4) immediately induced the efflux of the intracellular K+ ions and the cell death. A number of blebs were formed on the bacterial surface and the outer membrane became leaky. An increase in the peptide's positive charge enhanced the outer membrane permeabilization and the bactericidal activity. The cationic peptides also effectively permeabilized the inner membranes rich in acidic phospholipids, indicating the importance of electrostatic interactions. Substitution of Trp for Phe simultaneously increased the bactericidal activity and the hemolytic activity. A strategy to develop potent antimicrobial peptides was discussed on the basis of these results.

PF1092A, B and C, new nonsteroidal progesterone receptor ligands produced by Penicillium oblatum. II. Physico-chemical properties and structure elucidation

The structures of PF1092A (1), B (2) and C (3), new nonsteroidal progesterone receptor ligands produced by Penicillium oblatum, were elucidated by spectroscopic analyses. These compounds possess an eremophilane-type sesquiterpene carbon skeleton and differ only in that 1 and 2 are different monoacetates of 3. The absolute configurations of 1-3 were determined by single crystal X-ray diffraction analysis of the 4-bromobenzoyl ester of PF1092A and by measuring the optical rotations of the acetylation products of these compounds.

Giant hepatic angiomyolipoma associated with disseminated intravascular coagulation

We report a case of giant hepatic angiomyolipoma in a 68-year-old woman who had an increase in the fibrinolytic activity concomitant with disseminated intravascular coagulation (DIC). The presence of the tumor was confirmed by ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) of the abdomen and the selective arteriography of the liver via the superior mesenteric artery. Following treatment with heparin and gabexate mesilate, abnormal hemostatic values were corrected. Furthermore, the surgical removal of the huge hepatic angiomyolipoma completely normalized the alternations of the clotting system. These findings suggest that giant hepatic angiomyolipoma was profoundly associated with DIC.

Modulation of magainin 2-lipid bilayer interactions by peptide charge

Magainin 2, an antimicrobial peptide from Xenopus skin, assumes an amphiphilic helix when bound to acidic phospholipids, forming a pore composed of a dynamic, peptide-lipid supramolecular complex [Matsuzaki et al. (1996) Biochemistry 35, 11361-11368]. Upon the disintegration of the pore, a fraction of the peptide molecules stochastically translocates across the bilayer (Matsuzaki, et al., 1995). In order to investigate the effects of peptide charge on the magainin 2-lipid bilayer interactions, we synthesized four magainin 2 analogs with different charges (0-6+). MG0: K10E, K11E, F12W-magainin 2. MG2+: K10E, F12W-magainin 2. MG4+: F12W-magainin 2. MG6+: F12W, E19Q-magainin 2 amide. An increase in charge resulted in a stronger binding of the peptide to the negatively charged membranes, suggesting that electrostatic attractions play a crucial role in the binding process. The helical stability in a trifluoroethanol/buffer mixture was decreased with increasing positive charge because of electrostatic repulsions between the closely spaced positive side chains, whereas the helicity in the lipid bilayer was much higher and appeared to be independent of the peptide charge. However, enhanced repulsions between the highly positively charged helices destabilized the pore. Therefore, the efficiency of the most basic peptide (MG6+) to translocate across the bilayer was the greatest by virtue of the short life span of its pore and the very tight membrane binding. The charge distribution of wild-type magainin 2 was found to be so designed as to exhibit the maximal lytic activity by simultaneously achieving a strong binding and a moderate pore stability.

Effect of cholesterol on apolipoprotein A-I binding to lipid bilayers and emulsions

The effects of cholesterol (Chol) on the interaction of apolipoprotein A-I (apoA-I) with phospholipid bilayer vesicles and lipid emulsions were investigated. ApoA-I bound to phosphatidylcholine (PC) vesicles with higher affinity and lower capacity compared to triglyceride-PC emulsions. An increase in surface Chol in triglyceride-PC emulsions decreased the binding capacity without changing the binding affinity. In contrast, addition of Chol to PC vesicles caused a marked increase in capacity and decrease in affinity for apoA-I binding. ApoA-I caused a large release of entrapped aqueous dye, calcein, from PC vesicles, whereas this apoA-I-induced leakage was relatively small in the vesicles containing Chol. The incorporation of phosphatidylethanolamine into the vesicles also exerted effects similar to those of Chol on apoA-I binding and calcein leakage. The shifts of fluorescence emission maximum of dansyl lysine, probing the surface region of membranes, indicated that Chol as well as phosphatidylethanolamine increased the headgroup space of the vesicles. The binding maximum of apoA-I was closely correlated with the emission maximum of dansyl lysine, not with the fluorescence anisotropy of I-[4-(trimethylamino)phenyl]phenylhexatriene, suggesting that the binding capacity of apoA-I to the bilayer surface was modulated by the headgroup space rather than the acyl chain fluidity. These results show that Chol affects the bilayer surface so as to allow more apoA-I to bind to bilayers and may suggest the possibility of the interaction of apoA-I with Chol-enriched membrane domains.

[Lung volume reduction surgery for pulmonary emphysema--report of two cases]

Lung volume reduction surgery (LVR) was practiced in 2 male patients with pulmonary emphysema to improve pulmonary function. On admission, they complained of exertional dyspnea (Grade III of the Hugh-Jones dyspnea scale). Computed tomographic scan (band display) revealed emphysematous changes throughout both lung fields, especially in bilateral upper lobes. Nuclear lung perfusion scintigraphy showed markedly diminished blood flow in both upper lobes. The bilateral upper lobes of each patient were excised through median sternotomy using the linear stapling device. The staple lines were buttressed with bioabsorbable polyglycolic acid fabric. At 1 month after LVR, the forced expiratory volume in 1 second improved, respectively, from 0.51 L to 1.27 L (Case 1) and from 0.68 L to 0.85 L (case 2). In conclusion, LVR was useful to improve pulmonary function of the patients with pulmonary emphysema.

[Surgical treatment for patients with atypical mycobacteriosis]

We have been conducting surgical therapy for patients with atypical pulmonary mycobacteriosis (AM) since 1965 and have reported on the outcome of this approach to treatment. We have found that chemotherapy is not adequately efficacious against type III Mycobacterium avium complex (MAC), which suggests that surgical intervention may be the optimum approach for MAC. Among MAC patients who were treated surgically at our hospital in the period between 1966 and 1994, 74 cases on whom postoperative follow-up observation was possible served as the subjects of the present investigation. We report here on the outcome of treatment and related problems in these patients. Thirty-nine patients gave positive results for bacterial discharge on smear tests and all were positive on culture. Operation was performed on the right lung in 46 patients and on the left lung in 16. Pneumonectomy was conducted in 10 patients and lobectomy in 20. Other operative modes used included segmental resection in 9, pyothorax in 7, and thoracoplasty in 5 patients. Postoperative bacterial excretion was observed in 15 patients and was persistent bacterial discharge were advanced cases with lesions in another lobe, cases with a past history of tuberculosis, cases of cavitation with lesions on the contralateral side or cases with massive bacterial discharge prior to surgery. Postoperative death occurred in 5 patients: the cause of death was lung cancer in 1 case, serum hepatitis in 1 case, and respiratory failure evidenced by enlarged shadows in 3 cases. These findings pointed to a marked significance of surgical therapy for MAC patients. However, recurrent bacterial discharge has been observed occasionally in some patients even 5 years after surgery. This suggests the need for careful ongoing assessment of the efficacy of surgical therapy and long-term postoperative follow-up.

Sustained release of flufenamic acid from a drug-triacetyl-beta-cyclodextrin complex

Triacetyl-beta-cyclodextrin (TA-beta-CyD), a hydrophobic cyclodextrin derivative that is insoluble in water, was used to form a complex with flufenamic acid (FA). Complexes of FA with TA-beta-CyD (FA-TA-beta-CyD) at various molar ratios (1:1, 1:2, 1:3) were prepared by a kneading method, using ethanol as a solvent. FA-TA-beta-CyD complex formation was demonstrated by differential scanning calorimetry and powder X-ray diffractometry. The release rate of FA from the FA-TA-beta-CyD complexes was measured in both the Japanese Pharmacopoeia XII 1st fluid pH 1.2 and isotonic phosphate buffer pH 6.8. The release rate of FA from the FA-TA-beta-CyD complexes in the isotonic phosphate buffer pH 6.8 was significantly retarded compared to the release rate of FA from the FA-glucose mixture. After 1 h, 100% of the drug was released from the FA-glucose mixture and 10-25% was released from the complexes. When either the powder of the FA-glucose mixture or the FA-TA-beta-CyD mixture was administered directly into the intraduodenal lumen in rats, the plasma concentration of FA reached a maximum level within 40 min after administration. On the other hand, when the FA-TA-beta-CyD complexes were administered into the intraduodenal lumen, the plasma concentration of FA did not show a sharp peak, but remained at a plateau level (10-18 microg/ml) for 6-8 h. An increased mean residence time of FA following FA-TA-beta-CyD complexes administration was observed; however, the AUC(0-10) for the FA-TA-beta-CyD complexes showed no significant difference from that for the FA-TA-beta-CyD mixture. These results indicate that TA-beta-CyD may serve as a hydrophobic carrier in sustained-release preparations of FA. The drug-TA-beta-CyD complexes may therefore be useful in oral administration to achieve prolonged action and reduced side effects.

Lipid A and related compounds. XXX. Synthesis of biologically active N,N'-diacyl chitobiose derivatives structurally related to lipid A

Two new glycolipids, which mimic lipid A disaccharide, were synthesized from N,N'-diacylchitobiose via a key intermediate (2). They showed mitogenicity and nitric oxide (NO) productivity.

Craniofacial structure of Japanese and European-American adults with normal occlusions and well-balanced faces

The purpose of this study is to compare two groups of adults from different races who were selected on the basis of having normal ("ideal") occlusions and well-balanced faces. The lateral cephalometric radiographs of 54 Japanese adults (26 men and 28 women) were compared with a sample of 125 adults (44 men and 81 women) of European-American ancestry. The samples were chosen by orthodontists of the same racial background as the sample selected. Each lateral cephalogram was traced and digitized, and differences between cephalometric measurements between groups were analyzed with completely randomized t tests. In comparison to the European-American sample, the Japanese sample, in general, was smaller in anteroposterior facial dimensions and proportionately larger in vertical facial dimensions. The facial axis angle was more vertical in Japanese subjects, indicating a more downward direction of facial development. On average, the subjects in the Japanese sample were more protrusive dentally, with a more acute nasolabial angle and a greater tendency toward bilabial protrusion. These differences, evident even in groups with so-called "well-balanced faces", indicate that fundamental variation exists in the craniofacial structure of Japanese and European-Americans. The results of this study support the premise that a single standard of facial esthetics is not appropriate for application to diverse racial and ethnic groups.

An antimicrobial peptide, magainin 2, induced rapid flip-flop of phospholipids coupled with pore formation and peptide translocation

The effect of an antimicrobial peptide, magainin 2, on the flip-flop rates of phospholipids was investigated by use of fluorescent lipids, i.e., anionic N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)dipalmitoyl-L-alpha- phosphatidylethanolamine (NBD-PE), 1-oleoyl-2-[12-((7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)- dodecanoyl]-L-alpha-phosphatidic acid (C12-NBD-PA), 1-oleoyl-2-[12- ((7-nitrobenz-2-oxa-1,3-diazol-4-yl)- amino)dodecanoyl]-L-alpha-phosphatidyl-L-serine (C12-NBD-PS), and zwitterionic 1-palmitoyl-2-[6-((7- nitrobenz-2-oxa-1,3-diazol-4-yl)amino)caproyl]-L-alpha-phosphatidy lcholine (C6-NBD-PC). Their intrinsic flip-flop half-lives at 30 degrees C in the absence of the peptide were 1.1 h, ca. 7 h, ca. 8 days, and > 2 days, respectively. The peptide accelerated the flip-flop half-lives of the fluorescent lipids to an order of minutes. Furthermore, the flip-flop was coupled with the membrane permeabilization and the peptide translocation [Matsuzaki, K., Murase, O., Fujii, N., & Miyajima, K. (1995) Biochemistry 34, 6521-6526], suggesting pore-mediated flip-flop. The flip-flop rate was independent of the initial labeling conditions (outer leaflet label or inner leaflet label). From these results, a model was proposed, in which the lipids translocate across the membrane by lateral diffusion along the wall of the pores composed of the peptides and the lipids. A simple theoretical calculation could explain the coupling of the flip-flop with the permeabilization.

Orthodontic treatment of an open bite patient with oral-facial-digital syndrome

A case of oral-facial-digital syndrome was treated orthodontically. Characteristics of this case were mandibular protrusion with open bite. Occlusal stability after correction of this malocclusion was achieved with the uprighting of the posterior teeth, surgical reduction of the enlarged tonsils and highly attached tongue frenum, and oral functional training.

Load on the low back of teachers in nursery schools

In order to evaluate the load on the low back of teachers in nursery schools, basic activity, working posture, child-lifting, and desk-lifting were analyzed for eight nursery teachers using video recording. The trunk inclination angle (TIA) was also measured continuously during full workshifts for 20 nursery teachers using an inclination monitor. The nursery teachers in the 0-1 (year) age class more often adopted low working postures, "sitting on the floor" and "kneeling," while teachers in the 4-5 age class more frequently adopted high working postures, "standing" and "sitting on a chair." The mean of TIA among all subjects was 20 degrees. The time spent at a TIA of more than 20 degrees represented 43% of the workshift. The mean and time distribution of TIA did not differ between the age classes. The frequency of trunk-lifting from severe bending forward (TIA > 45 degrees) was 86 times/hour on average. The frequency of trunk-lifting was highest in the 0-1 age class. The number of times of child-lifting was 46 in the 0-1 age class, while it was 1 in the 4-5 age class.

Treatment mechanics in Class III open bite malocclusion with Tip Edge technique

Nonextraction treatment with nonorthognathic intervention for treatment of a skeletal Class III open bite malocclusion was performed. Light traction with effective uprighting of the lower dentition with Tip Edge brackets (TP Orthodontics, La Porte, Ind.) and anteriorly placed Class III elastics was the modus operandi. Class III elastics can prevent elongation of the upper molars and yet can cause the upper dentition to move forward. Ni-Ti wire with a reverse curve of Spee helped both the uprighting and depression of the mandibular molars. The present case was treated with the Kim philosophy but employing Tip Edge brackets. This combination was found to be very easy to manipulate and achieved good results in a very short period of time.

Correlation between lead in plasma and other indicators of lead exposure among lead-exposed workers

In order to clarify the bioavailability of lead in plasma (PbP), we performed a study on five workers in a Japanese factory manufacturing lead glass-based paints. Blood and urine samples were obtained over a period of 15 months, during which time the workers took it in turns to perform sifting work (with the highest level of lead exposure) for 1-month periods. A total of 75 sets of blood and urine samples were thus obtained. We determined whole blood lead (PbB), PbP, Urinary coproporphyrin (CPU), urinary delta-aminolevulinic acid (ALAU), urinary lead (PbU) and ALA in plasma (ALAP). In the 15 sets of samples obtained at the end of the period with a high level of lead exposure, PbP correlated significantly with ALAU, CPU, PbU and ALAP, but PbB correlated significantly only with PbU. In the 60 sets of samples obtained following a low level of lead exposure, correlation coefficients between the concentrations of PbP and of ALAU, CPU and PbU exceeded those between the concentrations of PbB and of ALAU, CPU and PbU. These findings indicate that PbP is a better dose indicator of lead biochemically available for heme synthesis and that PbU has a closer correlation with PbP than with PbB.

Physical states of surface and core lipids in lipid emulsions and apolipoprotein binding to the emulsion surface

Plasma triglyceride-rich lipoproteins vary in lipid composition during their metabolism. We investigated the effects of the lipid composition of emulsion particles, specifically those of cholesterol enrichment and core replacement (replacing core triglyceride with cholesteryl oleate), on the physical states of surface and core lipids. Steady-state and time-resolved fluorescence anisotropies were measured in lipid emulsions using 1,6-diphenylhexatriene to probe the core and 1,6-diphenylhexatriene analogues for the outer and inner hydrophobic portions of surface phospholipids. In the absence of cholesterol, core replacement had little effect on the surface rigidity, despite the large difference in core mobility. However, core replacement caused a marked increase in surface rigidity in the presence of cholesterol. Quenching experiments using the fluorescent cholesterol analogue, dehydroergosterol, indicated that core replacement allowed surface dehydroergosterol to redistribute from the inner to the outer regions in the emulsion surface. These results indicated that core replacement modulates the surface properties of the emulsion particles through the redistribution of cholesterol in the surface layers. Furthermore, core replacement significantly decreased the binding of apolipoprotein E to the emulsion surface, whereas the binding of apolipoprotein CII responded to the cholesterol enrichment. This binding behavior of exchangeable apolipoproteins may closely correlate with the location of surface cholesterol and the mobility of core lipids.

Transbilayer transport of ions and lipids coupled with mastoparan X translocation

The transbilayer movement of ions and lipids induced by mastoparan X, a peptidic toxin from Vespa xanthoptera, was investigated by use of lipid vesicles as a model membrane system. Negatively charged phosphatidylglycerol remarkably enhanced the peptide-lipid interactions. Mastoparan X induced the ion flow by forming a short-lived, multimeric pore in the lipid bilayer, as determined from the leakage of an anionic dye, calcein, from the liposomes. The pore formation was coupled with the translocation of the peptide into the inner leaflet. The latter was detected by three experiments using fluorescence techniques [Matsuzaki, K., Murase, O., Fujii, N., & Miyajima, K. (1995) Biochemistry 34, 6521-6526; Matsuzaki, K., Murase, O., & Miyajima, K. (1995) Biochemistry 34, 12553-12559]. The lipid flip flop was monitored on the basis of the chemical quenching of 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD)-labeled lipids by sodium dithionite. Mastoparan X triggered the rapid flip-flop of both negatively charged and zwitterionic lipids in coupling with the pore formation and the peptide translocation. A novel model of the mastoparan-lipid interactions was proposed to explain these observations.

Rapid and high yield induction of endometrial adenocarcinomas in CD-1 mice by a single intrauterine administration of N-ethyl-N-nitrosourea combined with chronic 17 beta-estradiol treatment

Induction of uterine endometrial adenocarcinomas in mice by N-ethyl-N-nitrosourea (ENU) and 17 beta-estradiol (E2) was examined. Illumination-induced persistent estrous CD-1 mice were divided into three groups at 10 weeks of age. Group 1 was given a single intra-uterine administration of polyethylene glycol (PEG) 1 week later, while Groups 2 and 3 received ENU (12.5 mg/kg), dissolved in PEG, in the same manner. Group 3 mice were also implanted with E2 pellets s.c. 1 week previously, and thereafter the pellets were renewed every 8 weeks throughout the experiment. At the termination (week 15 after the ENU treatment), all surviving mice were killed and the development of uterine proliferative lesions was assessed. All groups demonstrated endometrial hyperplasias, the severity being greatest in the ENU plus E2-treated animals (Group 3). The incidence of adenocarcinomas in Group 3 (20/29, 69%) was significantly higher than in Group 1 (0/25, 0%) or 2 (0/29, 0%). At 10 weeks after the ENU-treatment, serum E2 and progesterone concentrations in Group 3 were significantly higher and lower, respectively, than those in Groups 1 and 2. Consequently, the E2/progesterone (E2:P) ratio in Group 3 was significantly increased. These results indicate that a continuing high level of serum E2 and low level of progesterone are important for endometrial adenocarcinoma development in mice, with an increased E2:P ratio acting as a promoter for development of the endometrial lesions initiated by ENU treatment.

Effects of glucose and its oligomers on the stability of freeze-dried liposomes

The effects of glucose and its oligomers (maltodextrins) on the stability of sonicated liposomes during freeze-drying were studied by monitoring the retention of the fluorescent dye, Calcein, entrapped in the liposomal inner aqueous phase and by the use of differential scanning calorimetry (DSC). Glucose showed weak cryoprotective effects on dioleoylphosphatidylcholine (DOPC) or egg yolk phosphatidylcholine (eggPC) liposomes, while it had a relatively high cryoprotective effect on dipalmitoylphosphatidylcholine (DPPC) liposomes. Maltose and maltotriose showed high cryoprotective effects on eggPC liposomes, while other maltodextrin, longer oligomers, showed low cryoprotective effects. No saccharide was effective to protect DOPC liposomes. The fluidity and/or packing of lipid membranes had considerable influences on the stability of liposomes during the lyophilization. Maltodextrins showed relatively high cryoprotective effects on DPPC liposomes at low saccharide/lipid molar ratios, although the cryoprotective effects decreased with the increase in the molar ratios. Size measurements suggested that glucose and maltose completely prevented the aggregation and/or fusion of liposomes during lyophilization, and that other maltodextrins induced them due to their weak hydrophobic properties.