Probing the solvation of the α-helix with extended amide III bands in Raman optical activity.

Experimental and theoretical Raman optical activity (ROA) study of α-helical peptides and proteins has suggested that the relative intensity of two extended amide III ROA bands at ∼1340 cm-1 (I band) and ∼1300 cm-1 (II band) can be used to monitor the permittivity of the surrounding medium of the α-helix. So far, the ROA intensity ratio, II/III, has been interpreted from two different viewpoints. The first one is in terms of a direct effect of permittivity around the α-helix. The second one is based on a structural equilibrium of two types of α-helical structures, "hydrated" and "unhydrated" ones. In the present study, temperature- and solvent-dependences of II/III are measured for highly-α-helical peptides and compared to the theoretical spectra while varying the permittivity or the type of α-helical structure. A fragment method with partial optimization in the normal modes is adopted in density functional theory calculations. The main features of the experimental spectra and a trend of the observed II/III are well reproduced by the simulations, which leads us to a conclusion that the II/III is dominantly governed by a direct influence of the permittivity of the environment and just accessorily by the equilibrium of the two types of α-helices. The simulations also opposed the conventional assignments of the I and II bands to "hydrated" and "unhydrated" α-helical structures, respectively. In the case of α-helical proteins, solvent exposure of the α-helix may be monitored by the ROA ratio.

Advances, challenges and perspectives of quantum chemical approaches in molecular spectroscopy of the condensed phase.

The purpose of this review is to demonstrate advances, challenges and perspectives of quantum chemical approaches in molecular spectroscopy of the condensed phase. Molecular spectroscopy, particularly vibrational spectroscopy and electronic spectroscopy, has been used extensively for a wide range of areas of chemical sciences and materials science as well as nano- and biosciences because it provides valuable information about structure, functions, and reactions of molecules. In the meantime, quantum chemical approaches play crucial roles in the spectral analysis. They also yield important knowledge about molecular and electronic structures as well as electronic transitions. The combination of spectroscopic approaches and quantum chemical calculations is a powerful tool for science, in general. Thus, our article, which treats various spectroscopy and quantum chemical approaches, should have strong implications in the wider scientific community. This review covers a wide area of molecular spectroscopy from far-ultraviolet (FUV, 120-200 nm) to far-infrared (FIR, 400-10 cm-1)/terahertz and Raman spectroscopy. As quantum chemical approaches, we introduce several anharmonic approaches such as vibrational self-consistent field (VSCF) and the combination of periodic harmonic calculations with anharmonic corrections based on finite models, grid-based techniques like the Numerov approach, the Cartesian coordinate tensor transfer (CCT) method, Symmetry-Adapted Cluster Configuration-Interaction (SAC-CI), and the ZINDO (Semi-empirical calculations at Zerner's Intermediate Neglect of Differential Overlap). One can use anharmonic approaches and grid-based approaches for both infrared (IR) and near-infrared (NIR) spectroscopy, while CCT methods are employed for Raman, Raman optical activity (ROA), FIR/terahertz and low-frequency Raman spectroscopy. Therefore, this review overviews cross relations between molecular spectroscopy and quantum chemical approaches, and provides various kinds of close-reality advanced spectral simulation for condensed phases.

Intense chiral signal from α-helical poly-L-alanine observed in low-frequency Raman optical activity.

Raman optical activity (ROA) spectral features reliably indicate the structure of peptides and proteins, but the signal is often weak. However, we observed significantly enhanced low-frequency bands for α-helical poly-L-alanine (PLA) in solution. The biggest ROA signal at ∼100 cm-1 is about 10 times stronger than higher-frequency bands described previously, which facilitates the detection. The low-frequency bands of PLA were compared to those of α-helical proteins. For PLA, density functional simulations well reproduced the experimental spectra and revealed that about 12 alanine residues within two turns of the α-helix generate the strong ROA band. Averaging based on molecular dynamics (MD) provided an even more realistic spectrum compared to the static model. The low-frequency bands could be largely related to a collective motion of the α-helical backbone, partially modulated by the solvent. Helical and intermolecular vibrational coordinates have been introduced and the helical unwinding modes were assigned to the strongest ROA signal at 101-128 cm-1. Further analysis indicated that the helically arranged amide and methyl groups are important for the strong chiral signal of PLA, while the local chiral centers CαH contribute in a minor way only. The strong low-frequency ROA can thus provide precious information about the motions of the peptide backbone and facilitate future protein studies.

A Case of Mandibular Prognathism with Generalized Aggressive Periodontitis and Crowding.

Aggressive periodontitis during adolescence has a poor prognosis due to rapid alveolar bone resorption. Few studies have investigated long-term follow-up after surgical orthodontic treatment performed in conjunction with that for invasive periodontitis. Here, we report a case of mandibular prognathism accompanied by generalized aggressive periodontitis and crowding. A 31-year-old woman was referred to our department for treatment of masticatory dysfunction due to reverse overjet. The patient exhibited a class III molar relationship, protrusion of the ANB of －6.0°, and severe maxillary crowding. Initial periodontal examination revealed deep periodontal pockets and extensive inflammation. Mandibular prognathism accompanied by generalized aggressive periodontitis and crowding was diagnosed. Therefore, it was necessary to adopt an interdisciplinary approach involving surgical, orthodontic, and periodontal treatment. Prior to commencement of orthodontic treatment, plaque control, scaling, and root planing of all teeth were performed by a periodontist to suppress inflammation and reduce probing depth. During pre-surgical orthodontic treatment, the maxillary first premolars were extracted to reduce crowding of the maxillary incisors. To correct the mandibular prognathism, the mandible was repositioned by sagittal split ramus osteotomy. Proper occlusion of the incisors and maximum intercuspation were achieved by post-surgical orthodontic treatment. After completion of active orthodontic treatment, acceleration of inflammation was observed together with aggravated resorption of the alveolar bone surrounding the molars. However, reduction of probing depth and inflammation were observed after scaling and root planing. The surgical-orthodontic treatment time was 1 year and 11 months, which was followed by a 2-year retention period. There was no tooth loss due to periodontitis, and an overall satisfactory outcome was achieved.

Establishing the link between fibril formation and Raman optical activity spectra of insulin.

Folding of proteins into insoluble amyloidal fibrils is implicated in a number of biological processes. Optical spectroscopy represents a convenient tool to monitor such structural variations. Recently, characteristic changes in Raman optical activity (ROA) spectra of insulin during a pre-fibrillar stage were reported but not supported by a theoretical model. In the present study, molecular dynamics and the density functional theory are used to simulate the spectra and understand the connection between the structure, and ROA and Raman spectral intensities. Theoretical results are consistent with the observations and only confirm exceptional ROA sensitivity to the protein tertiary structure. Surprisingly, this sensitivity reflects local conformational changes in the peptide main and side chains, rather than a direct through-space interaction of the protein components. Side chains providing strong ROA signals, such as tyrosine, can additionally report on local conformational features. Theoretical modeling helps in explaining the observed spectral changes and is likely to enable future applications of ROA spectroscopy in protein structural studies.

[A CASE OF SUCCESSFUL MANAGEMENT BY LH-RH AGONIST FOR VESICOUTERINE FISTULA AFTER CESAREAN SECTION].

(Case) A 31-year-old woman noticed lower abdominal pain and urinary incontinence after voiding one month after third cesarean section. Cystoscopy and cystourethrography demonstrated a vesicouterine fistula at the posterior wall of the bladder. She complained of paroxysmal lower abdominal pain and slight incontinence without urge after voiding several times a month, which presented before and after menorrhea. Breast-feeding was ended 1 year after the labor, and then she underwent LH-RH agonist to keep amenorrhea. Urinary incontinence resolved completely within five months of hormonal therapy. During 8 years' follow-up, she remains asymptomatic and cystourethrography did not demonstrate the leakage. (Discussion) Most cases of vesicouterine fistula have been managed by surgical repair. As the pathophysiology of this disease resembles endometriosis, less-invasive hormonal therapy using LH-RH agonist can be a good treatment option before surgery.

Adjunct Antimicrobial Therapy and Periodontal Surgery to Treat Generalized Aggressive Periodontitis: A Case Report.

Here we report a case of generalized aggressive periodontitis treated with periodontal therapy including adjunct antimicrobial therapy and periodontal surgery. The patient was a 22-year-old woman who presented with the chief complaint of gingival recession. Baseline examination revealed generalized plaque deposition and gingival inflammation. Thirty-nine percent of the sites had a probing depth (PD) of 4-6 mm and 2% a PD of ≥7 mm; 63% exhibited bleeding on probing (BOP). Radiographic examination revealed vertical bone loss in the molars and horizontal bone loss in other teeth. Microbiological examination of subgingival plaque revealed the presence of Aggregatibacter actinomycetemcomitans and Tannerella forsythia. Oral health-related quality of life was assessed as a measure of patient-reported outcome. Based on a clinical diagnosis of generalized aggressive periodontitis, initial periodontal therapy and adjunct antimicrobial therapy were implemented. After reducing inflammation and subgingival bacteria, open flap debridement was performed for teeth with a PD of ≥4 mm. Reevaluation showed no sites with a PD of ≥5 mm, a minimal level of BOP, and a marked reduction in the level of the targeted periodontal pathogens. The patient's oral health-related quality of life was slightly worsened during supportive periodontal therapy (SPT). Implementation of adjunct antimicrobial therapy targeting periodontal pathogens and subsequent periodontal surgery resulted in improvement in periodontal and microbiological parameters. This improvement has been adequately maintained over a 2-year period. However, additional care is necessary to further improve the patient's oral health-related quality of life during SPT.

Etv1 and Ewsr1 cooperatively regulate limb mesenchymal Fgf10 expression in response to apical ectodermal ridge-derived fibroblast growth factor signal.

Fibroblast growth factors (FGFs) expressed in the apical ectodermal ridge (AER) and FGF10 expressed in the underlying mesoderm are essential for limb bud outgrowth. Their expression is maintained through a positive feedback loop. We identified the cis-regulatory element and trans-acting factors involved in the AER-FGF-dependent transactivation of Fgf10. Etv1 and Ewsr1 stimulated transcription from the Fgf10 promoter in the sub-AER mesenchyme of mouse and chick limb buds in a conserved AGAAAR cluster-dependent manner. We found that both Etv1 and Ewsr1 were necessary for Fgf10 expression and elongation of the limb bud. In addition, Etv1 and AER-FGF synergistically stimulated Fgf10 promoter activity in an Ewsr1-dependent manner. We also found that Etv1 and Ewsr1 bound to the segment of DNA containing the AGAAAR cluster in vivo and in vitro. Moreover, Etv1 directly bound to the AGAAAR sequence in vitro. Our results suggest that Etv1 and Ewsr1 transactivate Fgf10 directly and cooperatively in response to AER-FGFs.

In vitro cytotoxicity induced by Clostridium perfringens isolate carrying a chromosomal cpe gene is exclusively dependent on sporulation and enterotoxin production.

Clostridium perfringens type A is a common source of food poisoning (FP) and non-food-borne (NFB) gastrointestinal diseases in humans. In the intestinal tract, the vegetative cells sporulate and produce a major pathogenic factor, C. perfringens enterotoxin (CPE). Most type A FP isolates carry a chromosomal cpe gene, whereas NFB type A isolates typically carry a plasmid-encoded cpe. In vitro, the purified CPE protein binds to a receptor and forms pores, exerting a cytotoxic activity in epithelial cells. However, it remains unclear if CPE is indispensable for C. perfringens cytotoxicity. In this study, we examined the cytotoxicity of cpe-harboring C. perfringens isolates co-cultured with human intestinal epithelial Caco-2 cells. The FP strains showed severe cytotoxicity during sporulation and CPE production, but not during vegetative cell growth. While Caco-2 cells were intact during co-culturing with cpe-null mutant derivative of strain SM101 (a FP strain carrying a chromosomal cpe gene), the wild-type level cytotoxicity was observed with cpe-complemented strain. In contrast, both wild-type and cpe-null mutant derivative of the NFB strain F4969 induced Caco-2 cell death during both vegetative and sporulation growth. Collectively, the Caco-2 cell cytotoxicity caused by C. perfringens strain SM101 is considered to be exclusively dependent on CPE production, whereas some additional toxins should be involved in F4969-mediated in vitro cytotoxicity.

[INITIAL EXPERIENCE OF TRANSVAGINAL EXTRACTION OF THE KIDNEY FOLLOWING LAPAROSCOPIC NEPHRECTOMY IN OUR DEPARTMENT].

PURPOSE: We report the detailed technique and results of transvaginal extraction of the kidney following laparoscopic nephrectomy. PATIENTS AND METHODS: From August 2013 onward, we planned to perform transvaginal extraction of the kidney following laparoscopic nephrectomy in a total of 6 female patients. Of the 6 patients, 5 underwent the procedure. After completion of the primary laparoscopic nephrectomy and entrapping the removed kidney, the patients were placed in the supine lithotomy position. A transverse posterior colpotomy was created transvaginally at the apex of the posterior fornix. An opening was made in the peritoneum bluntly with the fingers under laparoscopic view. After the drawstring of the entrapped specimen was delivered into the vagina, the specimen was extracted intact via the vagina. When the vaginal wall was too tight for a large specimen, the incision was extended on the affected side. After removal of the specimen, the peritoneum was sutured laparoscopically, and the posterior colpotomy incision was repaired transvaginally. RESULTS: Transvaginal extraction was successful in 5 patients. The mean operative time for the vaginal extraction procedure was 59 minutes. Blood loss was minimal. The mean specimen weight was 447 g (range 271 to 655 g). No intraoperative complications occurred. Postoperatively, one case needed intermittent catheterization for a few days because of temporal dysfunction of the bladder. CONCLUSIONS: Transvaginal extraction is an efficacious and minimally morbid technique for removing the intact kidney after laparoscopic nephrectomy.

Solvated states of poly-L-alanine α-helix explored by Raman optical activity.

Raman optical activity (ROA) reveals surprising details of the secondary structure of polypeptides and proteins in solution phase. Yet specific spectral features, such as in the extended amide III region of hydrated α-helix, did not seem explicable by the generally accepted sensitivity of ROA to the local conformation. This is reconciled in the present study by simulations of ROA spectra for model α-helical structures. Two positive ROA peaks often observed at around 1340 and 1300 cm(-1) for polypeptides and proteins have been assigned to two types of solvated α-helices; one is stable in hydrophilic environment where amide groups make hydrogen bonds to solvent molecules or polar side chains (∼1340 cm(-1)), and the other is supported by a hydrophobic environment without the possibility of external hydrogen bonds (∼1300 cm(-1)). For poly-L-alanine (PLA), regarded as a good model of α-helical structure, the experimentally observed relative intensity ratio of the two ROA bands has been explained by a conformational equilibrium depending on the solvent polarity. The intensities of the bands reflect solvated and unsolvated α-helical geometries, with peptide backbone torsional angles (ϕi+1, ψi) of (-66°, -41°) and (-59°, -44°), respectively. Quantum-mechanical simulations of the ROA spectra utilizing the normal mode optimization and Cartesian tensor transfer methods indicate, however, that the change in dielectric constant of the solvent is the main factor for the spectral intensity change, whereas the influence of the conformational change is minor.

Magnetic circular dichroism of porphyrin lanthanide M3+ complexes.

Lanthanide complexes exhibit interesting spectroscopic properties yielding many applications as imaging probes, natural chirality amplifiers, and therapeutic agents. However, many properties are not fully understood yet. Therefore, we applied magnetic circular dichroism (MCD) spectroscopy, which provides enhanced information about the underlying electronic structure to a series of lanthanide compounds. The metals in the M(3+) state included Y, La, Eu, Tb, Dy, Ho, Er, Tm, Yb, and Lu; the spectra were collected for selected tetraphenylporphin (TPP) and octaethylporphin (OEP) complexes in chloroform. While the MCD and UV-VIS absorption spectra were dominated by the porphyrin signal, metal binding significantly modulated them. MCD spectroscopy was found to be better suited to discriminate between various species than absorption spectroscopy alone. The main features and trends in the lanthanide series observed in MCD and absorption spectra of the complexes could be interpreted at the Density Functional Theory (DFT) level, with effective core potentials on metal nuclei. The sum over state (SOS) method was used for simulation of the MCD intensities. The combination of the spectroscopy and quantum-chemical computations is important for understanding the interactions of the metals with the organic compounds.

Developing a national food defense guideline based on a vulnerability assessment of intentional food contamination in Japanese food factories using the CARVER+Shock vulnerability assessment tool.

The awareness of food terrorism has increased following the September 11, 2001 terrorist attacks in New York City, United States, and many measures and policies dealing with this issue have been established worldwide. Suspected deliberate food-poisoning crimes have occurred in Japan, although they are not regarded as acts of food terrorism. One area of concern is that the small- to medium-sized companies that dominate Japan's food industry are extremely vulnerable to deliberate food poisoning. We conducted a literature research on food defense measures undertaken by the World Health Organization and in the United States and Europe. Using the Carver+Shock vulnerability assessment tool, eight food factories and related facilities in Japan were evaluated and we found the level of awareness of food defense to be low and the measures inappropriate. On the basis of this evaluation, we developed a set of guidelines that Japanese food companies can use to help develop their food defense strategies and to serve as a reference in considering specific measures.

Tentative food defense guidelines for food producers and processors in Japan.

OBJECTIVES: With increasing global interest in intentional food contamination, expert meetings have been held by the G8, while the U.S. government has proposed policies for preventing food terrorism and intentional contamination. However, Japan has no food defense policy, and some food companies are concerned about an impending terrorism and contamination crisis. METHODS: We developed a Food Defense Checklist for Food Producers and Processors and published the details on the website. We also developed tentative Food Defense Guidelines for Food Producers and Processors on the basis of the checklist. In this study, we tested the usability of the guidelines through a hearing survey regarding food plants. We also compared the checklist with the implementation manual for the approval system of Comprehensive Sanitation Management and Production Process (the Japanese equivalent of the HACCP). RESULTS: We organized the comments gleaned from the hearing survey and provided a detailed explanation of the guidelines. As the HACCP has been adopted by Japanese food companies, we included both precautionary measures and the HACCP perspective in the explanation regarding the rapid dissemination of information. CONCLUSION: The guidelines are useful for Japanese food companies, and it is important to disseminate knowledge on this topic and implement food defense measures.

On the Commemorative Ceremony and Symposium for the 20th Anniversary of Food Safety Commission, Cabinet Office, Government of Japan.

Food Safety Commission, Cabinet Office, Government of Japan (FSCJ) was established in 2003 and marked its 20th anniversary in 2023. FSCJ held a commemorative ceremony and symposium to celebrate its 20th anniversary at Mita conference hall (Mita, Minato-ku, Tokyo) on September 1st, 2023, which attracted a total of 164 on-site attendees including six media companies, as well as 460 online viewers. FSCJ Chairperson Dr. YAMAMOTO gave a summary of each session; Session 1 outlined the various future challenges against which risk assessment organizations must prepare. In Session 2, panelists shared information on the development of new evaluation methodologies and international collaborations in order to meet various global demands and issues. In Session 3, the FSCJ introduced its future initiatives and called for international collaboration in sharing information and expertise to address data gaps and emerging issues, to which all panelists expressed their support. The importance of personnel development to tackle these challenges was also raised. In concluding the seminar, Dr. YAMAMOTO expressed that the common understanding gained from this occasion was the most fruitful achievement, owing to the international colleagues who shared their thought-provoking presentations and insights.

Transition polarizability model of induced resonance Raman optical activity.

Induced resonance Raman optical activity (IRROA) proved to be a very sensitive method to detect molecular chirality. It is exhibited, for example, by complexes of lanthanides with chiral alcohols or ketones. So far, the phenomenon has not been understood at a quantitative level. To elucidate its mechanisms and to correctly relate the spectra to the structure, a transition polarizability model (TPM) is developed and applied to a camphor-europium complex. The model well reproduces the high ROA/Raman intensity ratio of the IRROA observed experimentally. The results additionally indicate a fundamental role of the nonchiral fod ligand in the Eu(fod)3 compound for the chirality enhancement. The TPM model thus serves as a guidance for both experimental and theoretical studies to come.

New rotenoids and coumaronochromonoids from the aerial part of Boerhaavia erecta.

From the aerial part of Boerhaavia erecta L., three new rotenoids (3, 8, 10) and two new coumaronochromonoids (6, 11) were isolated, together with ten known compounds. The structure of the new compounds was established by one dimensional (1D)- and 2D-NMR spectroscopy, as well as high resolution-electrospray ionization (HR-ESI)-MS analysis. The absolute configuration of compound 11 was determined by UV circular dichroism spectroscopy. Compounds were evaluated for their cytotoxic activity against HeLa (human epithelial carcinoma), NCI-H460 (human lung cancer) and MCF-7 (human breast cancer) cell lines at the concentration of 100 µg/mL. Rotenoids 3, 4 and 5 showed a strong cytotoxic activity against HeLa cell line and rotenoids 5 and 8 showed good activity against MCF-7 cell line.

Crystal structure of Clostridium perfringens enterotoxin displays features of beta-pore-forming toxins.

Clostridium perfringens enterotoxin (CPE) is a cause of food poisoning and is considered a pore-forming toxin, which damages target cells by disrupting the selective permeability of the plasma membrane. However, the pore-forming mechanism and the structural characteristics of the pores are not well documented. Here, we present the structure of CPE determined by x-ray crystallography at 2.0 Å. The overall structure of CPE displays an elongated shape, composed of three distinct domains, I, II, and III. Domain I corresponds to the region that was formerly referred to as C-CPE, which is responsible for binding to the specific receptor claudin. Domains II and III comprise a characteristic module, which resembles those of ß-pore-forming toxins such as aerolysin, C. perfringens ε-toxin, and Laetiporus sulfureus hemolytic pore-forming lectin. The module is mainly made up of ß-strands, two of which span its entire length. Domain II and domain III have three short ß-strands each, by which they are distinguished. In addition, domain II has an α-helix lying on the ß-strands. The sequence of amino acids composing the α-helix and preceding ß-strand demonstrates an alternating pattern of hydrophobic residues that is characteristic of transmembrane domains forming ß-barrel-made pores. These structural features imply that CPE is a ß-pore-forming toxin. We also hypothesize that the transmembrane domain is inserted into the membrane upon the buckling of the two long ß-strands spanning the module, a mechanism analogous to that of the cholesterol-dependent cytolysins.

Structure and vibrational motion of insulin from Raman optical activity spectra.

The Raman optical activity (ROA) spectroscopic technique has been applied in the past to many biologically relevant systems including peptides, proteins, sugars, and even viruses. However, theoretical interpretation of the spectra relies on lengthy quantum-chemical computations, which are difficult to extend to larger molecules. In the present study, ROA and Raman spectra of insulin under a range of various conditions were measured and interpreted with the aid of the Cartesian-coordinate tensor transfer (CCT) method. The CCT methodology yielded spectra of insulin monomer and dimer of nearly ab initio quality, while at the same time reproducing the experimental data very well. The link between the spectra and the protein structure could thus be studied in detail. Spectral contributions from the peptide backbone and the amino acid side chains were calculated. Likewise, specific intensity features originating from the α-helical, coil, ß-sheet, and 3(10)-helical parts of the protein could be deciphered. The assignment of the Raman and ROA bands to intrinsic molecular coordinates as based on the harmonic force field calculation revealed their origin and degree of locality. Alternatively, the relation of the structural flexibility of insulin to the inhomogeneous broadening of spectral bands was studied by a combination of CCT and molecular dynamics (MD). The present study confirms the sensitivity of the ROA technique to some subtle static and dynamic changes in molecular geometry, and many previous ad hoc or semiempirical spectral-structure assignments could be verified. On the other hand, a limitation in longer-range tertiary structure sensitivity was revealed. Unlike for smaller molecules with approximately equal contributions of the electric dipole (α), quadrupole (A), and magnetic dipole (G') polarizabilities, only the electric dipolar polarization (α) interactions seem to dominate in the protein ROA signal. The simulations concern the largest molecule for which such spectra were interpreted by a priori procedures and significantly enhance protein folding studies undertaken by this technique.