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Lipid transbilayer movement (flip-flop) is regulated by membrane proteins that are involved in homeostasis and signaling in eukaryotic cells. In the plasma membrane, an asymmetric lipid composition is maintained by energy-dependent unidirectional transport. Energy-independent flip-flop promotion by phospholipid scramblases disrupts the asymmetry in several physiological processes, such as apoptosis and blood coagulation. In the endoplasmic reticulum, rapid flip-flop is essential for bilayer integrity because phospholipids are synthesized only in the cytoplasmic leaflet. Phospholipid scramblases are also involved in lipoprotein biogenesis, autophagosome formation, and viral infection. Although several scramblases have been identified and investigated, the precise flip-flop promotion mechanisms are not fully understood. Model transmembrane peptides are valuable tools for investigating the general effects of lipid-peptide interactions. We focus on the development of model transmembrane peptides with flip-flop promotion abilities and their mechanisms.

The kinetic mechanism of amyloid fibril formation by a peptide fragment containing seven residues of the amyloid-β protein Aβ-(16-22) was investigated. We found that the N- and C-terminal unprotected Aβ-(16-22), containing no aggregation nuclei, showed rapid fibrillation within seconds to minutes in a neutral aqueous buffer solution. The fibrillation kinetics were well described by the nucleation-elongation model, suggesting that primary nucleation was the rate-limiting step. On the basis of both experimental and theoretical analyses, the aggregated nucleus was estimated to be composed of 6-7 peptide molecules, wherein the two β-sheets were associated with their hydrophobic surfaces. Thin fibers with widths of 10-20 nm were formed, which increased their length and thickness, attaining a width of20 nm over several tens of minutes, probably owing to the lateral association of the fibers. Electrostatic and hydrophobic interactions play important roles in aggregation. These results provide a basis for understanding the fibrillation of short peptides.

Amphipathic α-helical peptides have been reported to form discoidal particles or nanodiscs with phospholipids, in which a lipid bilayer patch is encircled by peptides. Peptide-based nanodiscs have broad applicability because of their ease of preparation, size flexibility, and structural plasticity. We previously revealed that the nanodiscs formed by apolipoprotein-A-I-derived peptide 18A showed temperature-dependent structural destabilization above the gel-to-liquid-crystalline phase transition temperature of the lipid bilayer. It has been suggested that this destabilization is due to the migration of peptides bound to the edge of the discs to the bilayer surface. In this study, we designed a peptide that could stabilize nanodisc structures against the phase transition of lipid bilayers by disulfide cross-linking of peptides. An 18A-dimer cross-linked by a proline residue, 37pA (Ac-18A-P-18A-CONH

Self-assembling peptides form aggregates with various nanostructures such as spheres, sheets, and fibers and have potential applications in nanomedicine and drug delivery. The alkylation of peptides is a promising strategy for controlling the self-assembly of peptides. In this study, we investigated the thermodynamic properties associated with the aggregation of alkyl-chain-modified self-assembling peptides. The tripeptide sequence, KYF, which has been reported to form fibrous aggregates via self-assembly, was modified with various fatty acids at the N-terminus. The fibrous morphology of the aggregates was observed by transmission electron microscopy and atomic force microscopy. Thioflavin T fluorescence and circular dichroism spectroscopy revealed the formation of β-sheet structures. The critical micelle concentration and its temperature dependence were determined to obtain the thermodynamic parameters for aggregation. The results showed that the aggregation was an entropy-driven process at low temperatures, whereas it was enthalpy-driven at high temperatures. The negative heat capacity changes for aggregation suggested that hydrophobic interactions were the major driving force for self-assembly. Other entropic and enthalpic interactions were also contributed in part to the self-assembly. We individually identified the contributions of the peptide and alkyl chain moiety to the self-assembly. These contributions can be explained by the theoretical values for the self-assembly of each component. The results of this study provide fundamental insights into the design of self-associating peptides.

Understanding how lipid dynamics change with membrane curvature is important given that biological membranes constantly change their curvature and morphology through membrane fusion and endo-/exocytosis. Here, we used time-resolved small-angle neutron scattering and time-resolved fluorescence to characterize the properties and dynamics of phospholipids in vesicles with different curvatures. Dissociation of phospholipids from vesicles required traversing an energy barrier comprising positive enthalpy and negative entropy. However, lipids in membranes with high positive curvature have dense acyl chain packing and loose headgroup packing, leading to hydrophobic hydration due to water penetration into the membrane. These properties were found to lower the hydrophobic hydration enhancement associated with phospholipid dissociation and mitigate the acyl chain packing of lipids adjacent to the space created by the lipid dissociation, resulting in an increase in activation entropy. The results of this study provide important insights into the functions of biomembranes in relation to their dynamic structural changes.

Phospholipid scramblases that catalyze lipid transbilayer movement are associated with intercellular signaling and lipid homeostasis. Although several studies have shown that the hydrophilic residue-rich groove of the proteins mediates lipid scrambling, the interactions between the groove and the lipid bilayers remain poorly understood. Here we have revealed the structural features of model transmembrane peptides that conduct lipid scrambling as well as the interactions between the peptides and the surrounding lipids by means of experimental and simulation techniques. Peptides with two strongly hydrophilic residues located on the same side of the helices and at a deeper position in the membrane exhibited high scramblase activities. All-atom molecular dynamics simulations showed that the interactions between the hydrophilic residues and lipid head groups regulate the membrane thinning and disorder near the peptides in an order that correlates with the scramblase activity of the peptides. These results provide a basis for understanding the lipid scrambling mechanisms by transmembrane regions.

Background: Physicians currently measure the pupil diameter and the pupillary light reflex with visual observations using a ruler and a traditional penlight, leading to possibly inaccurate and subjective assessments. Although a mobile pupillometer has been developed and is available in clinical settings, this device can only assess one pupil at a time. Hence, an indirect pupillary light reflex, including those under irradiation to the opposite side of pupil, cannot be evaluated. Consequently, we have developed a new automatic mobile pupilometer, the Hitomiru®, with Hitomiru Co., Ltd. (Tokyo, Japan). This device is a two-glass type pupilometer with a video recording system. The pupil diameter and light reflex of both pupils can be measured simultaneously; therefore, both indirect and direct light reflexes can be assessed.Purpose: To evaluate the clinical ability of the Hitomiru® pupilometer to assess the pupil diameter and the pupillary light reflex of healthy volunteers and patients with intracranial lesions in an intensive care unit (ICU).Methods: Twenty-five healthy volunteers and five ICU patients with intracranial lesions on only the left side were assessed using the Hitomiru® pupilometer. The protocol was as follows: infrared light was applied to both pupils, followed by visible light to the right pupil, infrared light to both pupils, visible light to the left pupil, and then infrared light to both pupils. All the intervals were 2 s, and the dynamics of pupil diameters on both sides were continuously recorded.Results: The healthy adults had approximately 0.5 mm anisocoria, miosis was harder, and mydriasis was less with increased age. There were several differences in miosis rates, miosis times, and mydriasis rates between the healthy adults and the patients with intracranial lesions with both direct irradiation and indirect irradiation.Conclusions: The initial trial estimated and digitally recorded direct and indirect light reflexes, including rapidity of miosis after direct and indirect lights on, and mydriasis after direct and indirect lights off. The Hitomiru® pupilometer was a useful device to digitally record and investigate the relationship between pupil reflexes and intracranial diseases.

Purpose Facial expressions are formed by the coordination of facial muscles and reflect changes in emotion. Nurses observe facial expressions as way of understanding patients. This study conducted basic research using facial myogenic potential topography to visually determine changes in the location and strength of facial muscle activity associated with voluntary facial expression to examine relationships with facial expressions. Methods Participants comprised 18 healthy adults (6 men, 12 women; mean age, 24.3 ± 4.3 years). Facial myogenic potentials were measured from 19 electrodes arranged concentrically on the face, and topographic analysis was conducted. Using potential changes and topograms, the muscle activity associated with nonvoluntary facial expression and voluntary facial expressions of happiness and disgust were classified according to the characteristics of expressions. To classify homogeneous groups among the reaction of disgust, hierarchical cluster analysis was utilized. Results One characteristic of the facial expression of happiness was activity in areas including the greater zygomatic muscle. With the facial expression of disgust, characteristic changes were seen in areas including the corrugator supercilii. Cluster analysis of the expression of disgust showed four homogeneous subgroups. Conclusion With facial myogenic potential topography, facial expressions can be evaluated objectively without being influenced by face shape or countenance. Color changes in topograms showed subtle changes in expressions that could not be supplemented with statistical processing alone, and these were useful in identifying individuality. Topography is thus expected to be utilized to supplement basic knowledge of facial expressions for a better understanding of patients., With facial myogenic potential topography, facial expressions can be evaluated objectively without being influenced by face shape or countenance. Cluster analysis of the expression of disgust showed four homogeneous subgroups. Color changes in topograms showed subtle changes in expressions that could not be supplemented with statistical processing alone, and these were useful in identifying individuality.

The design of nanoassemblies is an important part of the development of new materials for applications in nanomedicine and biosensors. In our previous study, cysteine substitution of the apolipoprotein A-I-derived peptide 18A at residue 11, 18A[A11C], bound to 1-palmitoyl-2-oleoylphosphatidylcholine to form fibrous aggregates at a lipid-to-peptide molar ratio of ≤2 and a fiber diameter of 10-20 nm. However, the mechanisms underlying the lipid-peptide interactions that enable nanofiber formation remain unclear. Here, we evaluated the phospholipid specificity, concentration dependence, and temperature dependence of the formation of 18A[A11C]-lipid nanofibers. Nanofibers were found to form in the presence of specific phospholipids and have a constant lipid/peptide stoichiometry of 1.2 ± 0.2. Moreover, an increase in the length of the acyl chain in phosphatidylcholines was found to increase the structural stability of the nanofibers. These results indicate that specific molecular interactions between peptides and both the headgroups and acyl chains of phospholipids are involved in nanofiber formation. Furthermore, the formation and disassembly of the nanofibers were reversibly controlled by changes in temperature and concentration. The results of the present study provide an insight into the creation of nanoassembling structures.

Sec14, a yeast phosphatidylinositol/phosphatidylcholine transfer protein, functions at the trans-Golgi membranes. It lacks domains involved in protein-protein or protein-lipid interactions and consists solely of the Sec14 domain; hence, the mechanism underlying Sec14 function at proper sites remains unclear. In this study, we focused on the lipid packing of membranes and evaluated its association with in vitro Sec14 lipid transfer activity. Phospholipid transfer assays using pyrene-labelled phosphatidylcholine suggested that increased membrane curvature as well as the incorporation of phosphatidylethanolamine accelerated the lipid transfer. The quantity of membrane-bound Sec14 significantly increased in these membranes, indicating that "packing defects" of the membranes promote the membrane binding and phospholipid transfer of Sec14. Increased levels of phospholipid unsaturation promoted Sec14-mediated PC transfer, but had little effect on the membrane binding of the protein. Our results demonstrate the possibility that the location and function of Sec14 are regulated by the lipid packing states produced by a translocase activity at the trans-Golgi network.

Sec14, the major yeast phosphatidylcholine (PC)/phosphatidylinositol (PI) transfer protein (PITP), coordinates PC and PI metabolism to facilitate an appropriate and essential lipid signaling environment for membrane trafficking from trans-Golgi membranes. The Sec14 PI/PC exchange cycle is essential for its essential biological activity, but fundamental aspects of how this PITP executes its lipid transfer cycle remain unknown. To address some of these outstanding issues, we applied time-resolved small-angle neutron scattering for the determination of protein-mediated intervesicular movement of deuterated and hydrogenated phospholipids in vitro. Quantitative analysis by small-angle neutron scattering revealed that Sec14 PI- and PC-exchange activities were sensitive to both the lipid composition and curvature of membranes. Moreover, we report that these two parameters regulate lipid exchange activity via distinct mechanisms. Increased membrane curvature promoted both membrane binding and lipid exchange properties of Sec14, indicating that this PITP preferentially acts on the membrane site with a convexly curved face. This biophysical property likely constitutes part of a mechanism by which spatial specificity of Sec14 function is determined in cells. Finally, wild-type Sec14, but not a mixture of Sec14 proteins specifically deficient in either PC- or PI-binding activity, was able to effect a net transfer of PI or PC down opposing concentration gradients in vitro.

Objective The objective of this study was to clarify the types and prevalence of, and the risk factors for, the adverse events that occur in patients receiving anti-dementia drugs. Methods A questionnaire survey was conducted. The respondents were pharmacists who were dispensing anti-dementia drugs. The pharmacists responded to questions about patients who were receiving anti-dementia drugs delivered to them at home by the pharmacists. The survey questions included questions about whether or not the patients experienced adverse reactions to the drugs, about the patients’ background characteristics, about the numbers of drugs the patients were taking when the pharmacists first visited the patients at home, and about the pharmacists’ assessments of the appropriateness of the use of the anti-dementia drugs. Results Data were collected on 3712 patients from 1673 pharmacies in a nationwide survey. Anti-dementia drugs had been prescribed to 863 of these patients; and 801 (92.8%) of these 863 patients were 75 years of age or older, and. confirmed adverse events occurred in 170 (21%) of these 863 patients. The most common adverse event was excitation/anxiety, at 45.1%. A multivariate analysis found that polypharmacy (10 or more types of drugs per day) (P = 0.030), inappropriate use (P = 0.002), and irregular medication use (P = 0.034) were risk factors. Interpretation In order to avoid adverse events when using anti-dementia drugs, doctors and pharmacists should carefully examine the prescribing of multiple medications, assess the applicability of the use of anti-dementia drugs, and investigate how to best manage patients’ drug use.

Peptide-induced phospholipid flip-flop (scrambling) was evaluated using transmembrane model peptides in which the central residue was substituted with various amino acid residues (sequence: Ac-GKK(LA) nXW(LA) nLKKA-CONH2). Peptides with a strongly hydrophilic residue (X = Q, N, or H) had higher scramblase activity than that of other peptides, and the activity was also dependent on the length of the peptides. Peptides with a hydrophobic stretch of 17 residues showed high flip-promotion propensity, whereas those of 21 and 25 residues did not, suggesting that membrane thinning under negative mismatch conditions promotes the flipping. Interestingly, a hydrophobic stretch of 19 residues intensively promoted phospholipid scrambling and membrane leakage. The distinctive characteristics of the peptide were ascribed by long-term molecular dynamics simulation to the arrangement of central glutamine and terminal four lysine residues on the same side of the helix. The combination of simulated and experimental data enables understanding of the mechanisms by which transmembrane helices, and ultimately unidentified scramblases in biomembranes, cause lipid scrambling.

Background: The Macintosh laryngoscope enables safer and easy intubation. However, the mechanism of laryngeal exposure remains unclear. I hypothesized that extension of the hyoepiglottic ligament contributes to elevation of the epiglottis, and laryngoscope maneuvers that pull the hyoid bone rostrally will effectively elevate the epiglottis and expose the glottides. Methods: To test this hypothesis, I developed a model in which the epiglottis and hyoid bone were connected with a Velcro tape to allow flexible movement and applied different maneuvers to investigate their effects on epiglottis and hyoid bone movement. Results: A comparison of the original Macintosh maneuver, a modified Macintosh maneuver and the McCoy maneuver found that the McCoy maneuver elevated the epiglottis most, and was associated with rostral and anterior displacement of the hyoid bone. When the model was adjusted so that the hyoid bone was positioned caudal to the epiglottic vallecula, the hyoepiglottic ligament was shortened and the original Macintosh maneuver failed to elevate the epiglottis. Based on these results, a modified Macintosh maneuver was applied that elevated the hyoid bone rostrally and anteriorly and enhanced epiglottis elevation. Conclusions: The position of the hyoid bone should be considered to achieve epiglottic elevation and a good view of the glottides when performing laryngeal exposure. The position of the hyoid bone relative to the epiglottic vallecula could determine the response of the hyoepiglottic ligament and epiglottis elevation. Increased understanding of the mechanism of laryngeal exposure enables development of improved intubation devices and training models. J Curr Surg. 2018;8(1-2):1-6 doi: https://doi.org/10.14740/jcs348w

We usually associate triage with the Simple Triage and Rapid Treatment method, but much of its origin is still unknown. Therefore, French studies and the origin of triage shown in domestic and foreign published works have been investigated and its significance reaffirmed. The etymology of the word “triage” means “to break into three pieces.” It was suggested by a literature review that the rise of Napoleon led to military tactical changes, and that the prototype of triage arose from the experience gained in the difficult campaign in Egypt and Syria. Subsequently, triage was refined by Napoleon's military surgeon, D. J. Larrey, who created the ambulance transport system. Although there is a clash between the ruthless and philanthropic aspects of triage, triage is in accordance with the primary purpose of evacuation or treatment. We should choose the triage method that is consistent with the purpose of each disaster situation.

要旨 症例は77歳の男性。発熱と意識障害を主訴に救急搬送され，肺炎球菌による細菌性髄膜炎・敗血症の診断で入院となった。搬入時に2型糖尿病と白内障を認めていた。抗菌薬投与で速やかに感染徴候は改善を認めたが，第4病日より左眼痛を自覚し始め，第6病日に増悪したため眼科的診察を行い細菌性眼内炎と診断した。直ちに水晶体乳化吸引術と硝子体切除術を行ったが術後視力の回復は得られず，第22病日に退院となった。細菌性髄膜炎の治療中に細菌性眼内炎を合併することは極めて稀である。また，本症例は既往に白内障があり，眼内炎発症前から視力低下がみられていたうえ，髄膜炎による頭痛を入院時から認めており初期の眼痛との鑑別が困難であったため，診断に時間を要した。

Phospholipid transbilayer movement (flip-flop) in the plasma membrane is regulated by membrane proteins to maintain cell homeostasis and interact with other cells. The promotion of flip-flop by phospholipid scramblases causes the loss of membrane lipid asymmetry, which is involved in apoptosis, blood coagulation, and viral infection. Therefore, compounds that can artificially control flip-flop in the plasma membrane are of biological and medical interest. Here, we have developed lipid scrambling transmembrane peptides that can be inserted into the membrane. Time-resolved small-angle neutron scattering measurements revealed that the addition of peptides containing a glutamine residue at the center of the hydrophobic sequence to lipid vesicles induces the flip-flop of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. Peptides without the glutamine residue had no effect on the flip-flop. Because the glutamine-containing peptides exhibited scramblase activity in monomeric form, the polar glutamine residue would be exposed to the hydrocarbon region of the membrane, perturbing the membrane and promoting the lipid flip-flop. These scrambling peptides would be valuable tools to regulate lipid flip-flop in the plasma membrane.

要旨 triageといえばsimple triage and rapid treatment (START) methodが有名であるが，triage自体の起源は不明な点も多い。そこで国内外の文献に示されているtriageの起源を調べ，本邦でのtriageを再認識する。triageの語源には「3つに砕く」という意味がある。Napoleonの台頭による戦術の変化と，エジプト・シリア遠征での苦戦経験から戦力維持のためにtriageの原型が生まれたことが文献的考察によって示唆された。その後，Napoleon時代の軍医D. J. Larreyによって，triageは改良された。triageには非情に行わなければならない面と身分による区別なく行われるべき面とがあるが，避難または治療という主目的に付随したものであり，それぞれの災害状況の目的に合致したtriage法を選択すべきである。

要旨 症例は既往・内服歴のない56歳の男性で，搬入26日前に転倒し近医で胸部レントゲンを撮影され右肋骨骨折と診断されていた。保存的治療が選択され外来で経過観察されていたが，ワインボトルを開栓しようとした際に突然胸痛と冷汗が出現したため当センターに救急搬送された。搬入時はショックバイタルであり，胸部CTで右第9–11肋骨骨折と大量の胸腔内液貯留を認め大量血胸・出血性ショックと診断した。血管造影検査で肺動脈・第8–11肋間動脈からの造影剤漏出像を認めなかったが，2時間後に再検した胸部CTで血胸の増悪を認めていたため，直ちに胸腔鏡補助下で開胸手術を行った。術中所見では横隔膜損傷と同部位から動脈性の出血を認めており，肋骨骨折の治癒過程で横隔膜と癒着し，腹圧がかかったことで裂離し出血を来したものと推察された。術後経過良好であり，術後9日目に軽快退院となった。肋骨骨折において遅発的に血胸を認める症例報告の多くは肋間動脈からの出血であり，当症例のように横隔膜損傷に伴う血胸の報告は稀であるため，報告する。

Most biomembranes have an asymmetric structure with regard to phospholipid distribution between the inner and outer leaflets of the lipid bilayers. Control of the asymmetric distribution plays a pivotal role in several cellular functions such as intracellular membrane fusion and cell division. The mechanism by which membrane asymmetry and its alteration function in these transformation processes is not yet clear. To understand the significance of membrane asymmetry on trafficking and metabolism of intracellular vesicular components, a system that experimentally reproduces the asymmetric nature of biomembranes is essential. Here, we succeeded in obtaining asymmetric vesicles by means of transphosphatidylation reactions with phospholipase D (PLD), which acts exclusively on phosphatidylcholine (PC) present in the outer leaflet of vesicles. By treating PC vesicles with PLD in the presence of 1.7M serine and 0.3M ethanolamine, we obtained asymmetric vesicles that are topologically similar to intracellular vesicles containing phosphatidylserine and phosphatidylethanolamine in the cytosolic leaflet. PLD and other unwanted compounds could be removed by trypsin digestion followed by dialysis. Our established technique has a great advantage over conventional methods in that asymmetric vesicles can be provided at high yield and high efficiency, which is requisite for most physicochemical assays.

Background Evaluating the ratio of CD4/CD8 T-lymphocytes in the bronchoalveolar lavage fluid (BALF) is important for understanding the clinical and pathological conditions of patients with sarcoidosis. However, few studies have thus far demonstrated the usefulness of evaluating the relationship between the ratios of CD4/CD8 T-lymphocytes in the mediastinal lymph nodes and BALF. This study aimed to investigate and identify the relationships between CD4/CD8 T-lymphocyte ratio in the mediastinal lymph nodes and BALF in patients with sarcoidosis. Methods Thirty-three consecutive patients with sarcoidosis with enlarged mediastinal and/or hilar lymphadenopathy were enrolled in the study, and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and bronchoalveolar lavage (BAL) were simultaneously performed. The CD4/CD8 T-lymphocyte ratios in the mediastinal lymph nodes and BALF were evaluated using immunohistochemistry and flow cytometry, respectively. Results The interobserver variability in the CD4/CD8 ratio in the mediastinal lymph nodes as determined by immunostaining was low, and the pathological and cytological profiles of T-lymphocytes in the mediastinal and/or hilar lymph nodes and BALF were correlated in patients with sarcoidosis. Additionally, the CD4/CD8 T-lymphocyte ratios in BALF were significantly higher than those in the mediastinal lymph nodes. Importantly, non-caseating granulomas were detected at a high rate by using EBUS-TBNA. Conclusions Performing EBUS-TBNA in patients with sarcoidosis allows correct diagnosis as well as the estimation of the ratio of CD4/CD8 T-lymphocytes in BALF.

We designed three types of transmembrane model peptides whose sequence originates from a frequently used model peptide KALP23, and we investigated their effects on phospholipid flip-flop. Time-resolved small-angle neutron scattering and a dithionite fluorescent quenching assay demonstrated that TMP-L, which has a fully hydrophobic transmembrane region, did not enhance phospholipid flip-flop, whereas TMP-K and TMP-E, which have Lys and Glu, respectively, in the center of their transmembrane regions, enhanced phospholipid flip-flop. Introduction of polar residues in the membrane-spanning helices is considered to produce a locally polar region and enable the lipid head group to interact with the polar side-chain inside the bilayers, thereby reducing the activation energy for the flip-flop. A bioinformatics approach revealed that acidic and basic residues account for 4.5% of the central region of the transmembrane domain in human ER membrane proteins. Therefore, polar residues in ER membrane proteins are considered to provide flippase-like activity.

The mechanism whereby phospholipids rapidly flip-flop in the endoplasmic reticulum (ER) membrane remains unknown. We previously demonstrated that the presence of a hydrophilic residue in the center of the model transmembrane peptide sequence effectively promoted phospholipid flip-flop and that hydrophilic residues composed 4.5% of the central regions of the membrane-spanning sequences of human ER membrane proteins predicted by SOSUI software. We hypothesized that ER proteins with hydrophilic residues might play a critical role in promoting flip-flop. Here, we evaluated the flip rate of fluorescently labeled lipids in vesicles containing each of the 11 synthetic peptides of membrane-spanning sequences, using a dithionite-quenching assay. Although the flippase activities of nine peptides were unexpectedly low, the peptides based on the EDEM1 and SPAST proteins showed enhanced flippase activity with three different fluorescently labeled lipids. The substitution of hydrophobic Ala with His or Arg in the central region of the EDEM1 or SPAST peptides, respectively, attenuated their ability to flip phospholipids. Interestingly, substituting Ala with Arg or His at a location outside of the central region of EDEM1 or SPAST, respectively, also affected the enhancement of flip-flop. These results indicated that both Arg and His are important for the ability of these two peptides to increase the flip rates. The EDEM1 peptide exhibited high activity at significantly low peptide concentrations, suggesting that the same side positioning of Arg and His in α-helix structure is critical for the flip-flop promotion and that the EDEM1 protein is a candidate flippase in the ER.

Phospholipid flip-flop in the endoplasmic reticulum (ER) is very rapid and non-specific to phospholipid headgroups, which is necessary to maintain lipid homeostasis in the membrane. Much research suggested that the rapid flip-flop in the ER is mediated by membrane proteins. However, “flippases”, which are responsible for the flip-flop, have not been identified yet. We have previously demonstrated that peptide sequences that contain a hydrophilic residue in the transmembrane region are effective to promote the flip-flop and that such sequences can be seen in the transmembrane region of ER proteins predicted by SOSUI. Therefore, we hypothesized that ER proteins with hydrophilic residues in the transmembrane region may promote the flip-flop. In this study, we synthesized peptides with membrane-spanning sequences of several ER proteins and investigated their flip-flop promotion abilities by using fluorescent-labeled phospholipids. We found that the sequences of EDEM1 and SPAST promoted the flip-flop of fluorescent lipids non-selectively with respect to the glycerophospholipid structure. These two peptides contain both positively charged Arg and non-charged His near the center of the sequences. Thus, we next examined how the flip-flop promotion abilities were altered by substitution of hydrophobic Ala for Arg or His. The Arg to Ala mutation inhibited the flip-flop promotion abilities of each peptides completely, while the His to Ala mutation did partly. These results suggested that both Arg and His are responsible for the flip-flop promotion by the peptides and Arg plays a vital role in the activities. Considering the high activity of the EDEM1 peptide observed at significantly low peptide concentrations, EDEM1 protein might act as a “flippase”.

Background: Hyposalivation may affect respiratory disease because the mouth serves as the entrance to the respiratory apparatus, as well as to the digestive tract. Patients with acute respiratory infection generally have a favorable prognosis and a short natural course. However, in cases in which the host has lowered resistance, such as in elderly patients, the infection may develop into pneumonia. Objectives: A prospective study was performed to examine the relationship between hyposalivation, which is common in elderly patients, and acute respiratory infection, which tends to become severe in elderly patients. Methods: The subjects were 323 male and female patients ≥40 years old who lived in Utsunomiya City and surrounding areas and regularly visited the Department of Dentistry and Oral Surgery, Tochigi National Hospital. A 6-month follow-up survey was performed to examine development of acute respiratory infection. Age, sex, and known risk factors were also investigated. Hyposalivation was defined as a saliva production (saliva secretion rate) of ≤0.6 ml/min. Multivariate analysis adjusted for age and sex was performed to examine potential risk factors associated with the development of acute respiratory infection. Results: Data were analyzed for 278 subjects who completed the follow-up survey. The incidence of acute respiratory infection was 60.4%, while hyposalivation was present in 96 subjects (35.5%). Multivariate analysis showed that the incidence of acute respiratory infection was higher in subjects with hyposalivation than in those without hyposalivation (adjusted odds ratio 1.761, p = 0.048). Conclusion: The results of this study suggest that hyposalivation may be a risk factor for acute respiratory infection. This also suggests that improvement of hyposalivation might prevent acute respiratory infection.

Introduction: Hypospadias is a common congenital anomaly caused by incomplete fusion of urethral folds. Development of the urethra and external genital system in the male fetus is an androgen-dependent process. In this regard, enzymes 17β-hydroxysteroid dehydrogenase type 3 (17βHSD3, encoded by HSD17B3) and steroid 5α-reductase type 2 (encoded by SRD5A2) play crucial roles. Aim; To investigate the possible associations between common polymorphisms in HSD17B3 as well as well-known V89L polymorphism in SRD5A2 and risk of hypospadias. Methods: A case-control study was performed between 1999 and 2005. There were 89 Japanese boys with hypospadias and 291 newborn controls. We genotyped HSD17B3−1999T>C, +10A>G, +20A>G, +139G>A (V31I), +913G>A (G289S), and SRD5A2+336G>C (V89L) polymorphisms by allelic discrimination assay. We measured mRNA expression of the wildtype G289 allele and the mutant S289 allele of the HSD17B3 gene in the transfected human fetal kidney HEK293 cells. Main Outcome Measures: Assessment of hypospadias including its severity and HSD17B3 and SRD5A2 genes using DNA blood samples: allele and genotype distribution of single nucleotide polymorphisms in these two genes in cases and controls. Results: In our study, the risk of hypospadias was significantly higher in subjects carrying homozygous HSD17B3+913A (289S) alleles (odds ratio [OR]: 3.06; 95% confidence interval [CI]: 1.38–6.76). The risk of severe hypospadias was much higher in these subjects (OR: 3.93; 95% CI: 1.34–11.49). The mRNA expression levels of HSD17B3 G289 were higher than those of HSD17B3 S289 mutant (P < 0.001). In addition, the risk of severe hypospadias increased in boys carrying the SRD5A2+336C (89L) allele (OR: 3.19; 95% CI: 1.09–9.36). Conclusions: These results suggest that the HSD17B3 G289S polymorphism may be a potential risk modifier for hypospadias. Our findings provide evidence that a certain genotype related to androgen production may potentiate risk of hypospadias. Sata F, Kurahashi N, Ban S, Moriya K, Tanaka KD, Ishizuka M, Nakao H, Yahata Y, Imai H, Kakizaki H, Nonomura K, and Kishi R. Genetic polymorphisms of 17β-hydroxysteroid dehydrogenase 3 and the risk of hypospadias.

In July 2002, one of the largest outbreaks of Legionnaires' disease associated with a public bathhouse in Japan occurred in Miyazaki. The local government and the University of Miyazaki performed a retrospective investigation of those persons who were considered to have been exposed to Legionella. This investigation provided a unique opportunity to analyze the clinical presentation of patients with outbreak-associated Legionnaires' disease. The purpose of the present study was to analyze high-resolution computerized tomography (HRCT) scans for the characteristic findings of Legionnaires' disease and to evaluate the correlation between the radiological severity on the initial chest X-ray and the outcome of the patients. Radiological findings of HRCT were analyzed in 35 patients. The radiological severity on chest X-ray was evaluated in 69 patients, utilizing the pneumonia scoring system proposed by the Research Committee on Legionnaires' Disease of the Ministry of Health, Labour and Welfare of the Japanese Government. Air-space consolidation, ground-glass opacity, and pleural effusion were common features on HRCT in patients with Legionnaires' disease. Typical HRCT findings showed bilateral multilobar infiltrates in the subpleural areas without centrilobular opacities. Multivariate logistic regression analysis identified male sex, short incubation period, high serum C-reactive protein, high serum alanine aminotransferase, hyponatremia, and positive Legionella urinary antigen test results as independent risk factors for high pneumonia scores. Patients with high pneumonia scores required significantly longer hospitalization and showed poor prognoses.

Few reports have analyzed the clinical manifestations of patients with Legionnaires' disease in large outbreaks throughout the world. We retrospectively evaluated the clinical presentation and prognostic factors in 76 patients with Legionnaires' disease, reported by local physicians, in a large outbreak resulting from contamination of the water in a public bathhouse in Miyazaki, Japan. Fever, gastrointestinal tract symptoms, and abnormal neurological findings were seen in 95%, 35%, and 21% of the 76 patients, respectively. Respiratory tract symptoms were seen in only 42% of the patients, although all of these patients revealed pneumonia on chest X-ray. Only 20 (31%) of the 64 patients who had microbiological tests were reported to have positive results for one of the three microbiological tests (sputum culture, serology, and urinary antigen) which are specific for Legionella infection. Based on univariate analysis, the existence of neurological symptoms, elevated levels of C-reactive protein and transaminases, hyponatremia, a positive urinary antigen test, and serological evidence of Legionella infection were independent risk factors for poor clinical courses in patients with Legionnaires' disease. Patients treated with antimicrobial agents, such as macrolides, tetracyclines, and/or fluoroquinolones, within 3 days of onset of illness exhibited significantly better outcomes, when assessed by a multivariate logistic-regression model, after adjusting for the severity of pneumonia. Taking a careful history and documenting potential Legionella exposure, as well as microbiological testing, is important for an accurate diagnosis of Legionnaires' disease. Antimicrobials effective against Legionella bacteria should be administered without delay in subjects with suspected Legionnaires' disease.

BCG immunization, utilizing whole-body coordination, is a highly cost-effective means of health intervention for preventing miliary tuberculosis (TB) and TB meningitis. In this study, we investigated the appropriate age by which a child should have completed his or her BCG immunization and discuss the current BCG immunization rate in Akita Prefecture, Japan. BCG immunization rates in urban and rural areas were 90.1% and 80.7%, respectively. Our immunization data were lower than the World Health Organization's (WHO) recommended rate. Immunization coverage rates in urban settings were higher than those in rural areas among infants four months to fifteen months of age, except for those six months old. We recommend : (1) completing BCG immunization by the age of twelve months, (2) preparing and educating parents for BCG immunization by means of a health policy, and (3) changing BCG immunization methods from group to individual inoculation. Immunization coverage rates may be increased or maintained to prevent miliary TB and TB meningitis., Journal of physiological anthropology. 2007, 26(5), p.547-551

BACKGROUND Vascular calcification is an independent determinant of cardiovascular events in maintenance haemodialysis (HD) patients. It is not known whether acute changes of the serum calcium concentration before and after HD (DeltaCa) are associated with the development of aortic calcification. METHODS We enrolled 71 patients dialysed with a dialysate with 3.0 mEq/l calcium and determined their aortic calcification index (ACI) by abdominal computed tomography twice at an interval of 3 years. To identify the factors contributing to the rate of progression of aortic calcification, we analysed the average values for clinical and laboratory data obtained between the first and second evaluations of ACI. RESULTS The second ACI (mean+/-SD: 80.2+/-63.9) was significantly greater than the first ACI (61.0+/-61.0) after an interval of 35.8+/-4.2 months. The annualized change of ACI (DeltaACI/year) was significantly and directly associated with the DeltaCa and C-reactive protein (CRP) (both P

BACKGROUND: There are several alternative indicators of income information, which is a fundamental measure of individual socioeconomic position. In this study, we compared the degrees of associations of four types of income information with health variables among Japanese adults.METHODS: Using a nationally representative sample of 29,446 men and 32,917 women aged 20 years and over, the associations between four income indicators and health variables were examined using the odds ratio in logistic regression analysis and the concentration index by sex and age group (20-59 years and 60+ years). Income indicators consisted of total household income, equivalent household income, total household expenditure, and equivalent household expenditure. Current smoking and self-rated health statuses were used as health variables.RESULTS: A low income was associated with a high prevalence of smoking and fair/poor self-rated health, with some differences among sex and age groups and income indicators, but less difference among methods of statistical analyses. Total and equivalent incomes were similarly and more markedly associated with smoking and self-rated health statuses, whereas equivalent expenditure showed the smallest degree of health difference. For the population aged 60+ years, the degree of health differences in smoking was similar between income and expenditure.CONCLUSIONS: Although the degree of income-related health differences is dependent on health outcome and both sex and age group, this study suggests that either crude or equivalent household income is a useful indicator for health inequality among Japanese adults.J Epidemiol 2007; 17: 93-99.