[Understanding public health nurses' experience, knowledge, and perception of bioterrorism training in Japan].

Objectives　Bioterrorism is a disease in which the attacks can be covert and latent, take time to manifest, and, when discovered, can result in large outbreaks. When detected, they can become large-scale outbreaks. Therefore, preparedness is essential for early detection and response for damage mitigation. Although public health nurses (PHNs) of public health centers are responsible for detecting and dealing with bioterrorism, their preparation status is not clear. Therefore, this study aimed to elucidate the status of training experience, knowledge, and awareness of bioterrorism among PHNs working in public health centers' infectious disease control departments in Japan's metropolitan areas.Methods　This was a cross-sectional, descriptive study. The participants were PHNs in the infectious disease control departments of 88 public health centers in Tokyo and its three neighboring prefectures. This are densely populated metropolitan areas with many mass gathering events and a high probability of bioterrorism. An anonymous, self-administered questionnaire survey was conducted by mail in 2019. Two PHNs per location were surveyed regarding their attributes, training experience, knowledge, and perceptions.Results　We received 71 responses (40.3%). A total of 10 (14.1%) PHNs reported having experience with bioterrorism training in the workplace. Regarding the knowledge of the four infectious diseases with a high probability of bioterrorism, more than 95% of the respondents answered they had heard of them. However, few were aware of related treatments or terrorist responses. Although survey respondents were aware of the seriousness of bioterrorism and the effectiveness of preparedness, they did not have sufficient opportunity or time to have training. They tended to be less confident in their response and were willing to have training.Conclusion　PHNs who responded to this survey do not have sufficient training experience, knowledge, opportunities, and time for bioterrorism training, and establishing a training system to improve bioterrorism preparedness is a challenge. It will be necessary for PHN students to learn about the existence of bioterrorism. Further, PHNs in public health centers need to be trained at least once using online services, including brushing up on information as needed. Based on the lessons learned from the coronavirus disease 2019 pandemic, health centers will formulate a Health Crisis Management Plan. This will be effective in fiscal 2024, and we believe that it is essential that preparedness against bioterrorism be a part of this plan.

The evaluation of public health nursing students' skill achievement levels by educational improvement.

OBJECTIVE: This study aimed to evaluate the educational improvement outcomes after introducing undergraduate public health nursing electives from the perspective of students, teachers, and public health nurses. DESIGN AND SAMPLE: Post-test design with control group was used. We surveyed three groups of participants on the relevance of achieved skill items. These groups were as follows: fourth-year students, teaching staff from seven universities, and public health nurses from special districts of Tokyo who had pioneered the introduction of public health nursing electives. MEASURES: The three participant groups were surveyed in 2013 and 2014 to compare the students' levels of achievement in the 98 skill items presented by the Japanese Ministry of Health, Labour, and Welfare. Practical training introduced educational reform in 2014. Anonymous self-administrated questionnaires were used. RESULTS: The mean achievement rates of the 98 items in 2013 and 2014 were 67.9% and 72.6%, respectively, for students; 40.9% and 59.7% for teachers; and 44.4% and 59.4% for PHNs. A significant difference was observed between ratios of 2013 and 2014 in all three groups. CONCLUSIONS: The results demonstrated that the introduction of educational reform increased the achievement rates of students through the electives.

Cortical Actin Alteration at the Matrix-Side Cytoplasm in Lung Adenocarcinoma Cells and Its Significance in Invasion.

OBJECTIVES: Cortical actin is a thin layer of filamentous (F-)actin that lies beneath the plasma membrane, and its role in pathophysiology remains unclear. We investigated the subcellular localization of cortical actin by the histopathological and experimental studies of lung adenocarcinomas. MATERIALS AND METHODS: The subcellular localization of cortical actin was studied in surgically resected lung adenocarcinomas tissues and in 3-dimensionally cultured lung adenocarcinoma A549 cells. RESULTS: In normal type II alveolar cells and the bronchiolar epithelium, cortical actin was localized to the apical-side cytoplasm. In invasive adenocarcinoma cells, cortical actin was frequently localized to the matrix side. The degree of cortical actin localized to the matrix side was associated with the loss of basement membrane and a poor prognosis. In A549 cell spheroids cultured in a type I collagen and basement membrane extract Matrigel™ mixed gel, cortical F-actin was localized to the matrix side with phosphorylated myosin light chain. Super-resolution and electron microscopy results suggest that compact wrinkling of the plasma membrane by myosin-mediated F-actin contraction is an explanation for cortical actin accumulation at the matrix side. The myosin II inhibitor blebbistatin suppressed the 3-dimensional collective migration of A549 cells induced by constitutively active Cdc42 and MT1-MMP. CONCLUSION: Cortical actin accumulation at the matrix-side cytoplasm of cancer cells occurs in invasive lung adenocarcinomas and it possibly participates in the migration of cancer cells through myosin-mediated contraction.

Radiopathological Features and Identification of Mycobacterial Infections in Granulomatous Nodules Resected from the Lung.

BACKGROUND: Pulmonary granulomas are sometimes resected because they resemble lung cancer and false-positive findings come through from positron emission tomography (PET) using 18fluorine-fluorodeoxyglucose (18F-FDG). Mycobacterial infection is a common cause of granulomas. OBJECTIVE: The purpose of this study was to evaluate the radiopathological features and the methods for identifying mycobacterial infections in granulomatous nodules resected from the lung. METHODS: Thirty-five solitary lesions resected because of suspected lung cancer were enrolled, including 22 nonfungal granulomatous lesions and 13 benign lesions as controls. The radiological, microbiological, and histological findings were reviewed. To identify mycobacterial infection, immunohistochemical (IHC) staining, IS6110 polymerase chain reaction (PCR), and real-time PCR for the detection of Mycobacterium tuberculosis (TB) were performed using formalin-fixed and paraffin-embedded tissue specimens. The correlations between the radiopathological features and the median maximum standardized uptake value (SUVmax) of 18F-FDG PET were also evaluated. RESULTS: Mycobacteria were isolated from the cultures of 10 of the granulomatous lesions, including TB from 2 and Mycobacterium avium complex from 8. The mean size of the nodules in the culture-positive group was significantly larger than that of those in the culture-negative group (30.5 ± 13.1 vs. 15.1 ± 6.3 mm, p = 0.003). IHC stainings were positive in 15 granulomas. Eight granulomas were positive in IS6110 PCR, and 7 of them were also positive in real-time PCR. SUVmax was ≥2.5 in all of the PCR-positive granulomas. CONCLUSION: The most frequent cause of granulomatous lesions was mycobacterial infection. It seemed that the culture result was associated with nodule size and that the results of IS6110 were associated with 18F-FDG-uptake.

The different roles of innate immune receptors in inflammation and carcinogenesis between races.

Innate immune factors exert widespread effects on cytokine secretion, cell survival, autophagy, and apoptosis. Nucleotide-binding and oligomerization domain-like receptors (NLRs) are members of the innate immune system in the cytosol that sense pathogens, endogenous danger molecules such as uric acid, and pollutants. Nucleotide-binding oligomerization domain-containing protein 1 and 2 (NOD1 and NOD2) are components of NLR family, and ligands of these factors are γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP) and muramyl dipeptide (MDP), respectively. Upon recognition of ligands, NOD1 and NOD2 induce the production of inflammatory cytokines and transcription factors including interleukin-6 (IL-6) and nuclear factor-κB (NF-κB). We examined the function of NOD1 and NOD2 in innate immunity, with a focus on their differing roles in disease pathogenesis between Japanese and Caucasian populations. Susceptibility to several immune-related diseases, including Crohn's disease, colorectal and breast cancers, and graft-versus-host-disease (GVHD) showed a correlation with genetic variants of NOD2 in Caucasian, but not in Japanese, populations. This difference may be primarily due to the fact that three major NOD2 SNPs (R702W, G908R, L1007insC) prevalent in Caucasians are rare or absent in Japanese populations. Because NLR has diverse effects on immune function, it is possible that many as yet uncharacterized immune-related diseases will also show different susceptibilities between races due to the different ratio of genetic variants in innate immune genes.

Evaluation of skill achievement levels and practical experiences of public health nursing students before and after the introduction of the public health nursing course as an elective.

Objective To equip public health nurses (PHNs) with higher qualifications, PHN education is shifting from an integrated curriculum for PHNs and registered nurses to a specific elective system of undergraduate or postgraduate programs. Most colleges in the special wards of Tokyo introduced the elective system in 2014 before the remaining areas. The outcomes of this must be evaluated. This study aimed to evaluate the achievement levels and practical experiences of PHN students at seven colleges in the special wards before and after introduction of the PHN course as an elective.Method Self-administered, anonymous questionnaires were completed by senior PHN students at seven colleges in the special wards who underwent training in 2013, the last year of an integrated curriculum, and in 2014, the first year of the elective system. The target numbers of participants were 663 in 2013 and 136 in 2014 with 20 students from each school exposed to the elective system. Our study focused on whether they achieved the 98 "technical items of PHN training and achievement levels at the time of graduation" required by the Ministry of Health, Labour and Welfare. The study also determined whether participants obtained practical experience in 15 items developed by the special wards based on the standards set for training.Results In 2013, there were 348 total responses (52.5%) and 310 valid responses. In 2014, there were 136 total responses (88.2%) and 120 valid responses. The average achievement rate at which the student answered, "I was able to arrive at it," at an arrival degree level for the 98 technical items was 72.6% in 2014, an increase compared to the 67.9% obtained in 2013. Moreover, the average practical experience rate at which the student answered, "I was able to have an experience," regarding the 15 items was 85.7% in 2014, which constituted an increase compared to 70.5% attained in 2013. However, the number of items with an achievement rate of more than 80% remained at 31 (31.6%) in 2014.Conclusion Increasing percentages of average achievement and experience rate suggest that the lecture and training have improved, and highly motivated students could have been selected in the PHN program. However, students did not achieve the target rate for many of the items. Thus, there was a time limit to experience the technical item/the experience item.

Finding of 13(2) , 17(3) -cyclopheophorbide a enol as a degradation product of chlorophyll in shrunk zooxanthellae of the coral Montipora digitata.

We examined the morphology and pigment composition of zooxanthellae in corals subjected to normal temperature (27°C) and thermal stress (32°C). We observed several normal and abnormal morphological types of zooxanthellar cells. Normal cells were intact and their chloroplasts were unbroken (healthy); abnormal cells were shrunken and had partially degraded or broken chloroplasts, or they were bleached and without chloroplasts. At 27°C, most healthy zooxanthellar cells were retained in the coral tissue, whereas shrunken zooxanthellae were expelled. Under thermal stress, the abundance of healthy zooxanthellae declined and the proportion of shrunken/abnormal cells increased in coral tissues. The rate of algal cell expulsion was reduced under thermal stress. Within the shrunken cells, we detected the presence of a chl-like pigment that is not ordinarily found in healthy zooxanthellae. Analysis of the absorption spectrum, absorption maxima, and retention time (by HPLC) indicated that this pigment was 13(2) , 17(3) -cyclopheophorbide a enol (cPPB-aE), which is frequently found in marine and lacustrine sediments, and in protozoans that graze on phytoplankton. The production of cPPB-aE in shrunken zooxanthellae suggests that the chls have been degraded to cPPB-aE, a compound that is not fluorescent. The lack of a fluorescence function precludes the formation of reactive oxygen species. We therefore consider the formation of cPPB-aE in shrunken zooxanthellae to be a mechanism for avoiding oxidative stress.

Coexistence of nonfluorescent chromoproteins and fluorescent proteins in massive Porites spp. corals manifesting a pink pigmentation response.

Introduction: Several fluorescent proteins (FPs) and chromoproteins (CPs) are present in anthozoans and play possible roles in photoprotection. Coral tissues in massive corals often display discoloration accompanied by inflammation. Incidences of the pink pigmentation response (PPR) in massive Porites, described as inflammatory pink lesions of different shapes and sizes, has recently increased worldwide. FPs are reported to be present in PPR lesions, wherein a red fluorescent protein (RFP) appears to play a role in reducing reactive oxygen species. However, to date, the biochemical characterization and possible roles of the pigments involved are poorly understood. The present study aimed to identify and characterize the proteins responsible for pink discoloration in massive Porites colonies displaying PPRs, as well as to assess the differential distribution of pigments and the antioxidant properties of pigmented areas. Method: CPs were extracted from PPR lesions using gel-filtration chromatography and identified via genetic analysis using liquid chromatography-tandem mass spectrometry. The coexistence of CPs and RFP in coral tissues was assessed using microscopic observation. Photosynthetic antivity and hydrogen peroxide-scavenging activitiy were measured to assess coral stress conditions. Results: The present study revealed that the same CP (plut2.m8.16902.m1) isolated from massive Porites was present in both the pink spot and patch morphologies of the PPR. CPs were also found to coexist with RFP in coral tissues that manifested a PPR, with a differential distribution (coenosarc or tip of polyps' tentacles). High hydrogen peroxide-scavenging rates were found in tissues affected by PPR. Discussion and Conclusion: The coexistence of CPs and RFP suggests their possible differential role in coral immunity. CPs, which are specifically expressed in PPR lesions, may serve as an antioxidant in the affected coral tissue. Overall, this study provides new knowledge to our understanding of the role of CPs in coral immunity.

Analysis of the Effectiveness of Metaheuristic Methods on Bayesian Optimization in the Classification of Visual Field Defects.

Bayesian optimization (BO) is commonly used to optimize the hyperparameters of transfer learning models to improve the model's performance significantly. In BO, the acquisition functions direct the hyperparameter space exploration during the optimization. However, the computational cost of evaluating the acquisition function and updating the surrogate model can become prohibitively expensive due to increasing dimensionality, making it more challenging to achieve the global optimum, particularly in image classification tasks. Therefore, this study investigates and analyses the effect of incorporating metaheuristic methods into BO to improve the performance of acquisition functions in transfer learning. By incorporating four different metaheuristic methods, namely Particle Swarm Optimization (PSO), Artificial Bee Colony (ABC) Optimization, Harris Hawks Optimization, and Sailfish Optimization (SFO), the performance of acquisition function, Expected Improvement (EI), was observed in the VGGNet models for visual field defect multi-class classification. Other than EI, comparative observations were also conducted using different acquisition functions, such as Probability Improvement (PI), Upper Confidence Bound (UCB), and Lower Confidence Bound (LCB). The analysis demonstrates that SFO significantly enhanced BO optimization by increasing mean accuracy by 9.6% for VGG-16 and 27.54% for VGG-19. As a result, the best validation accuracy obtained for VGG-16 and VGG-19 is 98.6% and 98.34%, respectively.

Localization of propionibacterium acnes in granulomas supports a possible etiologic link between sarcoidosis and the bacterium.

Sarcoidosis likely results from the exposure of a genetically susceptible subject to an environmental agent, possibly an infectious one. Mycobacterial and propionibacterial organisms are the most commonly implicated potential etiologic agents. Propionibacterium acnes is the only microorganism, however, found in sarcoid lesions by bacterial culture. To evaluate the pathogenic role of this indigenous bacterium, we screened for the bacterium in sarcoid and non-sarcoid tissues using immunohistochemical methods with novel P. acnes-specific monoclonal antibodies that react with cell-membrane-bound lipoteichoic acid (PAB antibody) and ribosome-bound trigger-factor protein (TIG antibody). We examined formalin-fixed and paraffin-embedded samples of lungs and lymph nodes from 196 patients with sarcoidosis, and corresponding control samples from 275 patients with non-sarcoidosis diseases. The samples were mostly from Japanese patients, with 64 lymph node samples from German patients. Immunohistochemistry with PAB antibody revealed small round bodies within sarcoid granulomas in 20/27 (74%) video-assisted thoracic surgery lung samples, 24/50 (48%) transbronchial lung biopsy samples, 71/81 (88%) Japanese lymph node samples, and 34/38 (89%) German lymph node samples. PAB antibody did not react with non-sarcoid granulomas in any of the 45 tuberculosis samples or the 34 samples with sarcoid reaction. In nongranulomatous areas, small round bodies detected by PAB antibody were found in alveolar macrophages of lungs and paracortical macrophages of lymph nodes from many sarcoid and some non-sarcoid patients. Large-spheroidal acid-fast bodies, Hamazaki-Wesenberg bodies, which were found in 50% of sarcoid and 15% of non-sarcoid lymph node samples, reacted with both PAB and TIG antibodies. Electron microscopy revealed that these Hamazaki-Wesenberg bodies had a single bacterial structure and lacked a cell wall with occasional protrusions from the body. The high frequency and specificity of P. acnes, detected by PAB antibody within sarcoid granulomas, indicates that this indigenous bacterium might be the cause of granuloma formation in many sarcoid patients.

Tumor necrosis factor-alpha regulates transforming growth factor-beta-dependent epithelial-mesenchymal transition by promoting hyaluronan-CD44-moesin interaction.

Aberrant epithelial-mesenchymal transition (EMT) is involved in development of fibrotic disorders and cancer invasion. Alterations of cell-extracellular matrix interaction also contribute to those pathological conditions. However, the functional interplay between EMT and cell-extracellular matrix interactions remains poorly understood. We now show that the inflammatory mediator tumor necrosis factor-alpha (TNF-alpha) induces the formation of fibrotic foci by cultured retinal pigment epithelial cells through activation of transforming growth factor-beta (TGF-beta) signaling in a manner dependent on hyaluronan-CD44-moesin interaction. TNF-alpha promoted CD44 expression and moesin phosphorylation by protein kinase C, leading to the pericellular interaction of hyaluronan and CD44. Formation of the hyaluronan-CD44-moesin complex resulted in both cell-cell dissociation and increased cellular motility through actin remodeling. Furthermore, this complex was found to be associated with TGF-beta receptor II and clathrin at actin microdomains, leading to activation of TGF-beta signaling. We established an in vivo model of TNF-alpha-induced fibrosis in the mouse eye, and such ocular fibrosis was attenuated in CD44-null mice. The production of hyaluronan and its interaction with CD44, thus, play an essential role in TNF-alpha-induced EMT and are potential therapeutic targets in fibrotic disorders.

Localization of the invadopodia-related proteins actinin-1 and cortactin to matrix-contact-side cytoplasm of cancer cells in surgically resected lung adenocarcinomas.

OBJECTIVES: Actin-associated proteins at cell-matrix-contact sites form invadopodia in cancer cells and participate in migration, matrix degradation and invasion. We investigated an alteration of subcellular localization of invadopodia-related actin-associated proteins, actinin-1 and cortactin, in lung adenocarcinomas, its clinical significance, and its possible regulatory factors. METHODS: Invadopodia-related proteins, actinin-1 and cortactin, were immunohistochemically examined in 90 cases of lung adenocarcinomas. Expression of invadopodia-associated proteins and their possible regulators in lung adenocarcinomas were examined by real-time RT-PCR, database search, and immunohistochemistry. RESULTS: Actinin-1 and cortactin showed matrix-contact-side localization in adenocarcinoma cells, but rarely in normal bronchiolar epithelial cells, alveolar cells, or precursor lesion atypical adenomatous hyperplasia cells. Immunoelectron-microscopic examination of adenocarcinoma cells revealed actinin-1 localization to matrix-contact-side cytoplasm with cytoplasmic protrusions. Matrix-contact-side localization of actinin-1 and cortactin was correlated with tumor stages, lymph node metastasis, vascular permeation, and loss of basement membrane. The tumor-specific survival rate was worse for the group in which matrix-contact-side localization of cortactin was high than for the low group. mRNA of the Rho guanine exchange factor epithelial cell transforming sequence-2 (Ect2) tended to be overexpressed in lung adenocarcinomas and cytoplasmic expression of Ect2 tended to be correlated with matrix-contact-side localization of actinin-1. CONCLUSION: Matrix-contact-side localization of invadopodia-related proteins in the lung adenocarcinoma cells were correlated with invasion, metastasis, and poor prognosis. Ect2 was a possible regulator of matrix-contact-side localization of invadopodia-related proteins.

GATA3 abnormalities in six patients with HDR syndrome.

GATA3 mutations cause HDR (hypoparathyroidism, sensorineural deafness, and renal dysplasia) syndrome and, consistent with the presence of the second DiGeorge syndrome locus (DGS2) proximal to GATA3, distal 10p deletions often leads to HDR and DiGeorge syndromes. Here, we report on six Japanese patients with GATA3 abnormalities. Cases 1-5 had a normal karyotype, and case 6 had a 46,XX,del(10)(p15) karyotype. Cases 1-6 had two or three of the HDR triad features. Case 6 had no DiGeorge syndrome phenotype except for hypoparathyroidism common to HDR and DiGeorge syndromes. Mutation analysis showed heterozygous GATA3 mutations in cases 1-5, i.e., c.404-405insC (p.P135fsX303) in case 1, c.700T>C & c.708-709insC (p.F234L & p.S237fsX303) on the same allele in case 2, c.737-738insG (p.G246fsX303) in case 3, c.824G>T (p.W275L) in case 4, and IVS5+1G>C (splice error) in case 5. Deletion analysis of chromosome 10p revealed loss of GATA3 and preservation of D10S547 in case 6. The results are consistent with the previous finding that GATA3 mutations are usually identified in patients with two or three of the HDR triad features, and provide supportive data for the mapping of DGS2 in the region proximal to D10S547.

Physiological responses (Hsps 60 and 32, caspase 3, H2O2 scavenging, and photosynthetic activity) of the coral Pocillopora damicornis under thermal and high nitrate stresses.

This study explored the physiological responses of the coral Pocillopora damicornis to high nitrate concentrations and thermal stresses. The expression of heat shock proteins Hsp60 and Hsp32, Symbiodiniaceae density, Chl a concentration, Fv/Fm, H2O2 scavenging, and caspase 3 activity varied during 60 h incubations at 28 °C or 32 °C, ambient or high nitrate (~10 µM) concentrations, and their combinations. In combined stresses, corals showed a rapid and high oxidation level negatively affecting the Symbiodiniaceae density and Chl a concentration at 12 h, followed by caspase 3 and Hsps upregulations that induced apoptosis, bleaching and tissue detachment. Corals under thermal stress showed the highest oxidation and upregulation of Hsps and caspase 3 resulting in coral discoloration. High nitrate treatment alone did not seriously affect the coral function. Results showed that combined stress treatment severely affected coral physiology and, judging from the condition of detached tissues, these corals might have lower chances to recover.

Chlorophyll fluorescence - A tool to assess photosynthetic performance and stress photophysiology in symbiotic marine invertebrates and seaplants.

Chlorophyll a fluorescence is increasingly being used as a rapid, non-invasive, sensitive and convenient indicator of photosynthetic performance in marine autotrophs. This review presents the methodology, applications and limitations of chlorophyll fluorescence in marine studies. The various chlorophyll fluorescence tools such as Pulse-Amplitude-Modulated (PAM) and Fast Repetition Rate (FRR) fluorometry used in marine scientific studies are discussed. Various commonly employed chlorophyll fluorescence parameters are elaborated. The application of chlorophyll fluorescence in measuring natural variations, stress, stress tolerance and acclimation/adaptation to changing environment in primary producers such as microalgae, macroalgae, seagrasses and mangroves, and marine symbiotic invertebrates, namely symbiotic sponges, hard corals and sea anemones, kleptoplastic sea slugs and giant clams is critically assessed. Stressors include environmental, biological, physical and chemical ones. The strengths, limitations and future perspectives of the use of chlorophyll fluorescence technique as an assessment tool in symbiotic marine organisms and seaplants are discussed.

Xylan utilisation promotes adaptation of Bifidobacterium pseudocatenulatum to the human gastrointestinal tract.

Dietary carbohydrates impact the composition of the human gut microbiota. However, the relationship between carbohydrate availability for individual bacteria and their growth in the intestinal environment remains unclear. Here, we show that the availability of long-chain xylans (LCX), one of the most abundant dietary fibres in the human diet, promotes the growth of Bifidobacterium pseudocatenulatum in the adult human gut. Genomic and phenotypic analyses revealed that the availability of LCX-derived oligosaccharides is a fundamental feature of B. pseudocatenulatum, and that some but not all strains possessing the endo-1,4-ß-xylanase (BpXyn10A) gene grow on LCX by cleaving the xylose backbone. The BpXyn10A gene, likely acquired by horizontal transfer, was incorporated into the gene cluster for LCX-derived oligosaccharide utilisation. Co-culturing with xylanolytic Bacteroides spp. demonstrated that LCX-utilising strains are more competitive than LCX non-utilising strains even when LCX-derived oligosaccharides were supplied. In LCX-rich dietary interventions in adult humans, levels of endogenous B. pseudocatenulatum increased only when BpXyn10A was detected, indicating that LCX availability is a fitness determinant in the human gut. Our findings highlight the enhanced intestinal adaptability of bifidobacteria via polysaccharide utilisation, and provide a cornerstone for systematic manipulation of the intestinal microbiota through dietary intervention using key enzymes that degrade polysaccharide as biomarkers.

Molecular mechanisms regulating dissociation of cell-cell junction of epithelial cells by oxidative stress.

Oxidative stress is regarded as a causative factor in aging and various degenerative diseases. Here, we show the mechanism by which oxidative stress induces disruption of cell-cell junctions using retinal pigment epithelial cells. We demonstrated that reactive oxygen species (ROS)-mediated activation of Src kinase increases the tyrosine phosphorylation state of p120-catenin and rapidly triggers translocation of p120-catenin and internalization of N-cadherin from the cell-cell adhesion sites to an early endosomal compartment. Endosomal accumulation of p120-catenin resulted in stress fiber formation and cell-cell dissociation through the activation of Rho/Rho kinase pathway. However, these cytoskeletal remodeling and cell-cell dissociation induced by oxidative stress were transient, due to the activation of nuclear factor-kappaB (NF-kappaB) and the expression of manganese superoxide dismutase (Mn-SOD). Using the NF-kappaB specific inhibitor DHMEQ, we found that NF-kappaB is part of a negative feedback loop to control intracellular ROS levels. Finally, we demonstrated that H(2)O(2) treatment alone does not induce the epithelial mesenchymal transition (EMT) in retinal pigment epithelial cells, which can be induced by TNF-alpha treatment. These findings suggest that oxidative stress is a crucial factor to induce the cell-cell dissociation, an initial step of EMT, but does not provide sufficient signals to establish and to maintain the EMT.

Dinitrogen-fixing cyanobacteria in microbial mats of two shallow coral reef ecosystems.

Dinitrogen-fixing organisms in cyanobacterial mats were studied in two shallow coral reef ecosystems: La Reunion Island, southwestern Indian Ocean, Sesoko (Okinawa) Island, and northwestern Pacific Ocean. Rapidly expanding benthic miniblooms, frequently dominated by a single cyanobacterial taxon, were identified by microscopy and molecular tools. In addition, nitrogenase activity by these blooms was measured in situ. Dinitrogen fixation and its contribution to mat primary production were calculated using (15)N(2) and (13)C methods. Dinitrogen-fixing cyanobacteria from mats in La Reunion and Sesoko showed few differences in taxonomic composition. Anabaena sp. among heterocystous and Hydrocoleum majus and Symploca hydnoides among nonheterocystous cyanobacteria occurred in microbial mats of both sites. Oscillatoria bonnemaisonii and Leptolyngbya spp. occurred only in La Reunion, whereas Hydrocoleum coccineum dominated in Sesoko. Other mats dominated by Hydrocoleum lyngbyaceum, Phormidium laysanense, and Trichocoleus tenerrimus occurred at lower frequencies. The 24-h nitrogenase activity, as measured by acetylene reduction, varied between 11 and 324 nmoles C(2)H(2) reduced microg(-1) Chl a. The highest values were achieved by heterocystous Anabaena sp. performed mostly during the day. Highest values for nonheterocystous cyanobacteria were achieved by H. coccineum mostly during the night. Daily nitrogen fixation varied from nine (Leptolyngbya) to 238 nmoles N(2) microg(-1) Chl day(-1) (H. coccineum). Primary production rates ranged from 1,321 (S. hydnoides) to 9,933 nmoles C microg(-1) Chl day(-1) (H. coccineum). Dinitrogen fixation satisfied between 5% and 21% of the nitrogen required for primary production.

Quantitative PCR of Propionibacterium acnes DNA in samples aspirated from sebaceous follicles on the normal skin of subjects with or without acne.

To elucidate whether people with hair follicles containing many Propionibacterium acnes cells are prone to acne, we developed a novel method to count the number of P. acnes in hair follicles. We sampled sebaceous material in hair follicles by aspiration at a constant negative pressure from the nose, forehead, and upper arm of 86 patients with acne vulgaris and 209 control subjects with healthy skin, including 84 subjects age-matched to the patients. Genome-equivalents of P. acnes in samples were estimated by real-time quantitative PCR (TaqMan). Numbers of P. acnes genome-equivalents were extremely low in control subjects less than 10 years of age and generally higher at greater ages, with much variation in subjects in the same decade of life. In men, the median count was highest in controls aged 15-19 years; in women, it peaked twice, in controls aged 15-19 years and again in those aged 40 years or older. P. acnes counts on the forehead and nose were higher in the acne patients aged 10-14 years than in the age-matched controls in both sexes. The counts at three sites were similar in acne patients and controls aged 15 to 29 years in both sexes. The results suggest that people with hair follicles containing many P. acnes cells are not particularly prone to acne, except for younger teenagers. Our aspiration method with estimation by real-time PCR can be used to examine the cutaneous microflora of P. acnes.