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We report the complete genome sequences of six bacterial strains isolated from a floating macrophyte, duckweed. These six strains, representing the six dominant families of the natural duckweed microbiome, establish a simple model ecosystem when inoculated onto sterilized duckweed. Their genomes would provide insights into community assembly in plant microbiome., Competing Interests: The authors declare no conflict of interest.

Understanding the assembly of multispecies microbial communities represents a significant challenge in ecology and has wide applications in agriculture, wastewater treatment, and human healthcare domains. Traditionally, studies on the microbial community assembly focused on analyzing pairwise relationships among species; however, neglecting higher-order interactions, i.e., the change of pairwise relationships in the community context, may lead to substantial deviation from reality. Herein, we have proposed a simple framework that incorporates higher-order interactions into a bottom-up prediction of the microbial community assembly and examined its accuracy using a seven-member synthetic bacterial community on a host plant, duckweed. Although the synthetic community exhibited emergent properties that cannot be predicted from pairwise coculturing results, our results demonstrated that incorporating information from three-member combinations allows the acceptable prediction of the community structure and actual interaction forces within it. This reflects that the occurrence of higher-order effects follows consistent patterns, which can be predicted even from trio combinations, the smallest unit of higher-order interactions. These results highlight the possibility of predicting, explaining, and understanding the microbial community structure from the bottom-up by learning interspecies interactions from simple beyond-pairwise combinations., Competing Interests: Competing interests statement:The authors declare no competing interest.

Background: Lung cancer frequently occurs in lungs with background idiopathic interstitial pneumonias (IIPs). Limited resection is often selected to treat lung cancer in patients with IIPs in whom respiratory function is already compromised. However, accurate surgical margins are essential for curative resection; underestimating these margins is a risk for residual lung cancer after surgery. We aimed to investigate the findings of lung fields adjacent to cancer segments affect the estimation of tumor size on computed tomography compared with the pathological specimen., Methods: This analytical observational study retrospectively investigated 896 patients with lung cancer operated on at Fujita Health University from January 2015 to June 2020. The definition of underestimation was a ≥10 mm difference between the radiological and pathological maximum sizes of the tumor., Results: The lung tumors were in 15 honeycomb, 30 reticulated, 207 emphysematous, and 628 normal lungs. The ratio of underestimation in honeycomb lungs was 33.3% compared to 7.4% without honeycombing (P=0.004). Multivariate analysis showed that honeycombing was a significant risk factor for tumor size underestimation. A Bland-Altman plot represented wide 95% limits of agreement, -40.8 to 70.2 mm, between the pathological and radiological maximum tumor sizes in honeycomb lungs., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-22-1115/coif). The authors have no conflicts of interest to declare., (2023 Journal of Thoracic Disease. All rights reserved.)

We report the complete genome sequences of two predatory bacterial strains, Bacteriovorax sp. HI3 and Myxococcus sp. MH1, which were isolated from a freshwater pond. These two strains are grouped with the Bdellovibrio and like organisms and myxobacteria, respectively. Their genomes expand our knowledge of the characteristics of predatory bacteria.

Predatory bacteria, which prey on other bacteria, have significant functions in microbial ecosystems and have attracted increasing attention for their biotechnological use. However, knowledge of the characteristics of wild-type environmental predatory bacteria remains limited. This study isolated two predatory bacteria, Bacteriovorax stolpii HI3 and Myxococcus sp. MH1, from a freshwater pond and characterized their predation capabilities. Determination of the prey range using 53 potential prey strains, including 52 environmental strains, revealed that B. stolpii HI3 and Myxococcus sp. MH1 could prey on a wide spectrum of Gram-negative bacteria and a broader range of bacteria, irrespective of phylogeny, in accordance with the common characteristics of Bdellovibrio and like organisms and myxobacteria, respectively. Liquid culture assays also found that although predation by B. stolpii HI3 rapidly and largely occurred, the prey bacteria regrew, possibly through plastic phenotypic resistance to predation. In contrast, predation by Myxococcus sp. MH1 occurred at relatively low efficiency but was longer lasting. The two strains exhibited slightly distinct temperature preferences but commonly preferred slightly alkaline pH. The novel findings of this study provide evidence for the coexistence of predatory bacteria with diverse predation capabilities in the natural aquatic environment.

In recent years, the choice of immune checkpoint inhibitors (ICIs) as a treatment based on high expression of programmed death-ligand 1 (PD-L1) in lung cancers has been increasing in prevalence. The high expression of PD-L1 could be a predictor of ICI efficacy as well as high tumor mutation burden (TMB), which is determined using next-generation sequencing (NGS). However, a great deal of effort is required to perform NGS to determine TMB. The present study focused on γH2AX, a double-strand DNA break marker, and the suspected positive relation between TMB and γH2AX was investigated. We assessed the possibility of γH2AX being an alternative marker of TMB or PD-L1. One hundred formalin-fixed, paraffin-embedded specimens of lung cancer were examined. All of the patients in the study received thoracic surgery, having been diagnosed with lung adenocarcinoma or squamous cell carcinoma. The expressions of γH2AX and PD-L1 (clone: SP142) were evaluated immunohistochemically. Other immunohistochemical indicators, p53 and Ki-67, were also used to estimate the relationships of γH2AX. Positive relationships between γH2AX and PD-L1 were proven, especially in lung adenocarcinoma. Tobacco consumption was associated with higher expression of γH2AX, PD-L1, Ki-67, and p53. In conclusion, the immunoexpression of γH2AX could be a predictor for the adaptation of ICIs as well of as PD-L1 and TMB.

Background: Tracheobronchial injury in children is rare but can be highly fatal in severe cases. Therefore, prompt diagnosis and treatment are required. The appropriate treatment method depends on the extent and severity of the injury., Case Presentation: An 8-year-old girl fell from the fifth floor and was transported to a local hospital. She had a tracheobronchial injury, went into cardiopulmonary arrest during transportation to our hospital. She was revived with cardiopulmonary resuscitation, and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) was commenced. Subsequently, we performed tracheobronchial reconstruction by inverted Barclay's method for tracheobronchial injury. She was switched from VA-ECMO to venovenous (VV)-ECMO 4 days postoperatively, and VV-ECMO was eventually discontinued 27 days after the surgery. The patient was awake and weaned off the ventilator on postoperative day 58. She was discharged 97 days after the surgery., Conclusions: Tracheobronchial reconstruction by inverted Barclay's method is the preferred surgical technique when other reconstruction techniques are expected to cause excessive tension on the anastomosis of the right main bronchus., (© 2022. The Author(s).)

Bacterial communities associated with aquatic macrophytes largely influence host primary production and nutrient cycling in freshwater environments; however, little is known about how specific bacteria migrate to and proliferate at this unique habitat. Here, we separately identified bacterial genes involved in the initial colonization and overall fitness on plant surface, using the genome-wide transposon sequencing (Tn-seq) of Aquitalea magnusonii H3, a plant growth-promoting bacterium of the floating macrophyte, duckweed. Functional annotation of identified genes indicated that initial colonization efficiency might be simply explained by motility and cell surface structure, while overall fitness was associated with diverse metabolic and regulatory functions. Genes involved in lipopolysaccharides and type-IV pili biosynthesis showed different contributions to colonization and fitness, reflecting their metabolic cost and profound roles in host association. These results provide a comprehensive genetic perspective on aquatic-plant-bacterial interactions, and highlight the potential trade-off between bacterial colonization and proliferation abilities on plant surface., (© 2022. The Author(s).)

The collapse of Comamonas testosteroni R2 under chemostat conditions and the aerobic growth of strain R2 under batch conditions with phenol as the sole carbon source were investigated using physiological and transcriptomic techniques. Phenol-/catechol-degrading activities under chemostat conditions gradually decreased, suggesting that metabolites produced from strain R2 accumulated in the culture, which caused negative feedback. The competitive inhibition of phenol hydroxylase and catechol dioxygenase was observed in a crude extract of the supernatant collected from the collapsed culture. Transcriptomic analyses showed that genes related to nitrogen transport were up-regulated; the ammonium transporter amtB was up-regulated approximately 190-fold in the collapsed status, suggesting an increase in the concentration of ammonium in cells. The transcriptional levels of most of the genes related to gluconeogenesis, glycolysis, the pentose phosphate pathway, and the TCA and urea cycles decreased by ~0.7-fold in the stable status, whereas the activities of glutamate synthase and glutamine synthetase increased by ~2-fold. These results suggest that ammonium was assimilated into glutamate and glutamine via 2-oxoglutarate under the limited supply of carbon skeletons, whereas the synthesis of other amino acids and nucleotides was repressed by 0.6-fold. Furthermore, negative feedback appeared to cause an imbalance between carbon and nitrogen metabolism, resulting in collapse. The effects of amino acids on negative feedback were investigated. L-arginine allowed strain R2 to grow normally, even under growth-inhibiting conditions, suggesting that the imbalance was corrected by the stimulation of the urea cycle, resulting in the rescue of strain R2.

Objectives: The aim of the present study was to examine some initial results and learning curves concerning subxiphoid single-port thymectomy (SSPT), thereby clarifying the safety of this surgical approach and describing the precautions for adopting it., Methods: From March 2011 to August 2019, a total of 203 patients underwent thymectomy for either anterior mediastinal tumours or myasthenia gravis at Fujita Health University Hospital. Of these 203 patients, 147 patients who had undergone SSPT were selected as participants for the present study., Results: Of the 147 cases, transition to a different approach was required in three (2.0%) cases: two (1.3%) cases transitioned to median sternotomy, whereas one (0.7%) case transitioned to the side chest trans-intercostal approach. The two cases that transitioned to median sternotomy were the second cases for different operators after they began performing this technique. There were six (4.0%) cases with complications and no deaths. The operation time cumulative summation learning curve analysis revealed that the curves descended from the 38th case. In the 83 cases handled by one surgeon, the learning curves descended from the 31st case., Conclusions: SSPT is a safe modality with few complications and no associated cases of mortality reported. Operators are required to experience 31-38 cases until the operation time for SSPT was stabilized. Special care should be exercised to prevent vascular damage in the vicinity of the innominate veins during the early stages after SSPT introduction., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Plant growth-promoting bacteria (PGPB) have recently been demonstrated as a promising agent to improve wastewater treatment and biomass production efficiency of duckweed hydrocultures. With a view to their reliable use in aqueous environments, this study analysed the plant colonization dynamics of PGPB and the ecological consequences for the entire duckweed-associated bacterial community. A PGPB strain, Aquitalea magnusonii H3, was inoculated to duckweed at different cell densities or timings in the presence of three environmental bacterial communities. The results showed that strain H3 improved duckweed growth by 11.7-32.1% in five out of nine experiments. Quantitative-PCR and amplicon sequencing analyses showed that strain H3 successfully colonized duckweed after 1 and 3 d of inoculation in all cultivation tests. However, it significantly decreased in number after 7 d, and similar bacterial communities were observed on duckweed regardless of H3 inoculation. Predicted metagenome analysis suggested that genes related to bacterial chemotactic motility and surface attachment systems are consistently enriched through community assembly on duckweed. Taken together, strain H3 dominantly colonized duckweed for a short period and improved duckweed growth. However, the inoculation of the PGPB did not have a lasting impact due to the strong resilience of the natural duckweed microbiome., (© FEMS 2020.)

Objective: Precise prediction of postoperative pulmonary function is extremely important for accurately evaluating the risk of perioperative morbidity and mortality after major surgery for lung cancer. This study aimed to compare the accuracy of a single-photon emission computed tomography/computed tomography (SPECT/CT) method that we recently developed for predicting postoperative pulmonary function versus the accuracy of both the conventional simplified calculating (SC) method and the method using planar images of lung perfusion scintigraphy., Methods: The relationship between the postoperative observed % values of the forced expiratory volume in 1 second (FEV 1 ) or diffusing capacity for carbon monoxide (DL CO or DL CO ') and the % predicted postoperative (%ppo) values of FEV 1 , DL CO , or DL CO ' calculated by the three methods were analyzed in 30 consecutive patients with lung cancer undergoing lobectomy., Results: The relationship between the postoperative observed % values and %ppo values calculated by the three methods exhibited a strong correlation (Pearson r>0.8, two-tailed p <0.0001). The limits of agreement between the postoperative % values and %ppo values did not differ among the three methods. The absolute values of the differences between the postoperative % values and %ppo values for FEV 1 and DL CO ' were comparable among the three methods, whereas those for DL CO of SPECT/CT were significantly higher than those of the planar method. Conversely, in patients with preoperative %DL CO ' of <80% predicted, the absolute values of the differences between the postoperative %DL CO ' and %ppoDL CO ' of SPECT/CT tended to be smaller than those of the SC and planar methods., Conclusion: The accuracy of SPECT/CT for predicting postoperative pulmonary function is comparable with that of conventional methods in most cases, other than in some patients with diffusion impairment., Competing Interests: The authors state that they have no conflicts of interest to declare. No funding was accepted for this study.

A complete understanding of the plant microbiome has not yet been achieved due to its complexity and temporal shifts in the community structure. To overcome these issues, we created a synthetic bacterial community of the aquatic plant, duckweed. The synthetic community established with six bacterial strains showed a stable composition for 50 days, which may have been because duckweed maintains a similar physiological status through its clonal reproduction. Additionally, the synthetic community reflected the taxonomic structure of the natural duckweed microbiome at the family level. These results suggest the potential of a duckweed-based synthetic community as a useful model system for examining the community assembly mechanisms of the plant microbiome.

Objective: We compared post-thoracotomy pain syndrome (PTPS) incidence in patients who underwent uniportal or multiportal video-assisted thoracoscopic surgery (VATS)., Methods: We included 223 patients who underwent either uniportal or multiportal VATS between January 2017 and October 2018 (pulmonary lobectomies and pulmonary segmentectomies-uniportal: n =19, multiportal: n =133; wedge lung resections-uniportal: n =16, multiportal: n =55). We retrospectively studied incidences of PTPS in all subgroups., Results: Incidences of PTPS were significantly less for uniportal procedures for both the pulmonary lobectomy/segmentectomy group ( P =0.024) and the wedge lung resection group ( P =0.0315) than for multiportal procedures., Conclusion: Patients who underwent uniportal VATS procedures had lower incidences of PTPS than the multiportal VATS group. The uniportal VATS approach is therefore beneficial for patients., Competing Interests: We have no conflicts of interest to declare with regard to this study.

Plant growth-promoting bacteria (PGPB) are considered a promising tool to improve biomass production and water remediation by the aquatic plant, duckweed; however, no effective methodology is available to utilize PGPB in large hydroponic systems. In this study, we proposed a two-step cultivation process, which comprised of a "colonization step" and a "mass cultivation step," and examined its efficacy in both bucket-scale and flask-scale cultivation experiments. We showed that in the outdoor bucket-scale experiments using three kinds of environmental water, plants cultured through the two-step cultivation method with the PGPB strain, Acinetobacter calcoaceticus P23, yielded 1.9 to 2.3 times more biomass than the control (without PGPB inoculation). The greater nitrogen and phosphorus removals compared to control were also attained, indicating that this strategy is useful for accelerating nutrient removal by duckweed. Flask-scale experiments using non-sterile pond water revealed that inoculation of strain P23 altered duckweed surface microbial community structures, and the beneficial effects of the inoculated strain P23 could last for 5-10 d. The loss of the duckweed growth-promoting effect was noticeable when the colonization of strain P23 decreased in the plant. These observations suggest that the stable colonization of the plant with PGPB is the key for maintaining the accelerated duckweed growth and nutrient removal in this cultivation method. Overall, our results suggest the possibility of an improved duckweed production using a two-step cultivation process with PGPB., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Fiber Bragg grating (FBG) sensors fabricated in silica optical fiber (Silica-FBG) have been used to measure the strain of human arteries as pulse wave signals. A variety of vital signs including blood pressure can be derived from these signals. However, silica optical fiber presents a safety risk because it is easily fractured. In this research, an FBG sensor fabricated in plastic optical fiber (POF-FBG) was employed to resolve this problem. Pulse wave signals were measured by POF-FBG and silica-FBG sensors for four subjects. After signal processing, a calibration curve was constructed by partial least squares regression, then blood pressure was calculated from the calibration curve. As a result, the POF-FBG sensor could measure the pulse wave signals with an signal to noise (SN) ratio at least eight times higher than the silica-FBG sensor. Further, the measured signals were substantially similar to those of an acceleration plethysmograph (APG). Blood pressure is measured with low error, but the POF-FBG APG correlation is distributed from 0.54 to 0.72, which is not as high as desired. Based on these results, pulse wave signals should be measured under a wide range of reference blood pressures to confirm the reliability of blood pressure measurement uses POF-FBG sensors.

A small-size, high-precision fiber Bragg grating interrogator was developed for continuous plethysmograph monitoring. The interrogator employs optical edge filters, which were integrated with a broad-band light source and photodetector to demodulate the Bragg wavelength shift. An amplifier circuit was designed to effectively amplify the plethysmograph signal, obtained as a small vibration of optical power on the large offset. The standard deviation of the measured Bragg wavelength was about 0.1 pm. The developed edge filter module and amplifier circuit were encased with a single-board computer and communicated with a laptop computer via Wi-Fi. As a result, the plethysmograph was clearly obtained remotely, indicating the possibility of continuous vital sign measurement.

Background: This study aimed to investigate the initial results of an endoscopic surgical approach for the treatment of intramediastinal ectopic parathyroid adenoma and to evaluate the effectiveness of a single-incision resection using the subxiphoid approach., Methods: Five cases of patients (1.89%) were diagnosed with ectopic mediastinal parathyroid tumor and underwent resection from 2008 to 2017 in Fujita Health University Hospital. They were retrospectively analyzed., Results: Four patients underwent single-port mediastinal tumor resection using the subxiphoid approach and 1 patient underwent multi-port mediastinal tumor resection using the lateral thoracic approach. The operation time was 134±83.52 min, and the amount of blood loss was 81.8±173.41 mL. The rate of conversion to thoracotomy was 0%, and no intraoperative or postoperative complications were observed. The amount of postoperative oral analgesics was 112.83±209.12 tablets, and their administration period was 561.6±1,229.5 days. The length of hospital stay was 4±2.35 days, and the duration of chest tube drainage was 1.33±1.95 days. The patient who underwent multi-port mediastinal tumor resection using the lateral thoracic approach reported postoperative pain. Serum calcium levels decreased from 10.56±1.52 mg/dL preoperatively to 8.96±0.5 mg/dL postoperatively, and serum phosphorous levels increased from 2.84±0.42 mg/dL preoperatively to 3.6±0.51 mg/dL postoperatively. Intact-PTH hormone levels decreased from 221±169.84 pg/dL preoperatively to 70.2±44.28 pg/dL postoperatively. No recurrence of hyperparathyroidism has been observed in any patient., Conclusions: The single-incision mediastinal tumor resection via the subxiphoid approach, without going through the intercostal space, is considered as a useful endoscopic surgical approach for the treatment of mediastinal ectopic parathyroid adenomas due to the limited occurrence of post-thoracotomy pain syndrome and the superior esthetic outcomes associated with the procedure as compared to thoracotomy and median sternotomy., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Acinetobacter ursingii M3 and Asticcacaulis excentricus M6 are plant growth-inhibiting bacteria that reduce the yield of the duckweed Lemna minor. We report here the complete genome sequences of A. ursingii M3 and A. excentricus M6, sequenced using the PacBio RS II platform.

This paper describes and verifies a non-invasive blood glucose measurement method using a fiber Bragg grating (FBG) sensor system. The FBG sensor is installed on the radial artery, and the strain (pulse wave) that is propagated from the heartbeat is measured. The measured pulse wave signal was used as a collection of feature vectors for multivariate analysis aiming to determine the blood glucose level. The time axis of the pulse wave signal was normalized by two signal processing methods: the shortest-time-cut process and 1-s-normalization process. The measurement accuracy of the calculated blood glucose level was compared with the accuracy of these signal processing methods. It was impossible to calculate a blood glucose level exceeding 200 mg/dL in the calibration curve that was constructed by the shortest-time-cut process. In the 1-s-normalization process, the measurement accuracy of the blood glucose level was improved, and a blood glucose level exceeding 200 mg/dL could be calculated. By verifying the loading vector of each calibration curve to calculate the blood glucose level with a high measurement accuracy, we found the gradient of the peak of the pulse wave at the acceleration plethysmogram greatly affected., Competing Interests: The authors declare no conflict of interest.

Sphingobium fuliginis OMI is a bacterium that can degrade a variety of recalcitrant alkylphenols and bisphenols. This study reports the draft genome sequence of S. fuliginis OMI., (Copyright © 2017 Kuroda et al.)

Aquitalea magnusonii strain H3 is a promising plant growth-promoting bacterium for duckweed. Here, we report the draft genome sequence of strain H3 comprising 4,750,601 bp in 73 contigs. Several genes associated with plant root colonization were identified., (Copyright © 2017 Ishizawa et al.)

Background: Duckweed (family Lemnaceae ) has recently been recognized as an ideal biomass feedstock for biofuel production due to its rapid growth and high starch content, which inspired interest in improving their productivity. Since microbes that co-exist with plants are known to have significant effects on their growth according to the previous studies for terrestrial plants, this study has attempted to understand the plant-microbial interactions of a duckweed, Lemna minor , focusing on the growth promotion/inhibition effects so as to assess the possibility of accelerated duckweed production by modifying co-existing bacterial community., Results: Co-cultivation of aseptic L. minor and bacterial communities collected from various aquatic environments resulted in changes in duckweed growth ranging from -24 to +14% compared to aseptic control. A number of bacterial strains were isolated from both growth-promoting and growth-inhibitory communities, and examined for their co-existing effects on duckweed growth. Irrespective of the source, each strain showed promotive, inhibitory, or neutral effects when individually co-cultured with L. minor . To further analyze the interactions among these bacterial strains in a community, binary combinations of promotive and inhibitory strains were co-cultured with aseptic L. minor , resulting in that combinations of promotive-promotive or inhibitory-inhibitory strains generally showed effects similar to those of individual strains. However, combinations of promotive-inhibitory strains tended to show inhibitory effects while only Aquitalea magnusonii H3 exerted its plant growth-promoting effect in all combinations tested., Conclusion: Significant change in biomass production was observed when duckweed was co-cultivated with environmental bacterial communities. Promotive, neutral, and inhibitory bacteria in the community would synergistically determine the effects. The results indicate the possibility of improving duckweed biomass production via regulation of co-existing bacterial communities.

In this paper, we propose a blood pressure calculation and associated measurement method that by using a fiber Bragg grating (FBG) sensor. There are several points at which the pulse can be measured on the surface of the human body, and when a FBG sensor located at any of these points, the pulse wave signal can be measured. The measured waveform is similar to the acceleration pulse wave. The pulse wave signal changes depending on several factors, including whether or not the individual is healthy and/or elderly. The measured pulse wave signal can be used to calculate the blood pressure using a calibration curve, which is constructed by a partial least squares (PLS) regression analysis using a reference blood pressure and the pulse wave signal. In this paper, we focus on the influence of individual differences from calculated blood pressure based on each calibration curve. In our study, the calculated blood pressure from both the individual and overall calibration curves were compared, and our results show that the calculated blood pressure based on the overall calibration curve had a lower measurement accuracy than that based on an individual calibration curve. We also found that the influence of the individual differences on the calculated blood pressure when using the FBG sensor method were very low. Therefore, the FBG sensor method that we developed for measuring the blood pressure was found to be suitable for use by many people., Competing Interests: The authors declare no conflict of interest.

Plasma profiles of glucose, insulin and lipids were examined in the male WBN/Kob-Lepr(fa) (fa/fa) rat, a new model of type 2 diabetes (T2D), in comparison with age-matched original male WBN/Kob (lean) rats. The fa/fa rats developed hypertriglycemia, obesity and hyperglycemia from 5, 7, and 9 weeks of age, respectively. Plasma insulin levels in fa/fa rats were significantly higher than those in lean rats at 5 weeks of age, but after 11 weeks of age gradually declined to the levels in lean rats. HOMA-IR, a measure of insulin resistance status, showed that fa/fa rats had insulin resistance. The fa/fa rat has the potential to become an important animal model of T2D with obesity.

Ghosts and flares are well-known problems that are caused by reflections from lens surfaces when we take photographs. It is more difficult to prevent such stray light in a digital camera than in a film camera because of high reflectance from the low-pass filter and diffraction from the image sensor. To prevent such stray light, we introduce an ultralow refractive index layer into the antireflective (AR) coatings. We used the solgel method to form porous fluoride layers with ultralow refractive indices, and we succeeded in developing a unique process to form AR coatings with superior performance.

We have successfully developed a process to form high quality MgF(2) thin films with ultralow refractive indices from autoclaved sols prepared from magnesium acetate and hydrofluoric acid. And we have confirmed that our porous MgF(2) coatings have not only high transmittance in the UV region but also high uniformity of film thickness. They can be uniformly formed on phiv 300 mm substrates as a single coating and as a hybrid coating with sublayers formed by physical vapor deposition. They are expected to be applied to various optics that need high transmittance in the UV region.

Porous MgF(2)-SiO(2) thin films consisting of MgF(2) particles connected by an amorphous SiO(2) binder are prepared by a solgel process. The films have a low refractive index of 1.26, sufficient strength to withstand wiping by a cloth, and a high environmental resistance. The refractive index of the film can be controlled by changing the processing conditions. Films can be uniformly formed on curved substrates and at relatively low temperatures, such as 100 degrees C. The low refractive index of the film, which cannot be achieved by conventional dry processes, is effective in improving the performance of antireflective coatings.

An ultralow refractive index is very advantageous when one designs antireflective coatings. We successfully obtained high-quality MgF2 thin films with ultralow refractive indices from autoclaved sols prepared from magnesium acetate and hydrofluoric acid. The MgF2 films consist of nanosized particles, and they have high laser-exposure durability at 193 nm. The reflectance of the antireflective coating with five layers, of which the top layer is formed by our method, is lower than 0.6% in the incident angle range of 0 degrees - 60 degrees at 193 nm.

A phosphodiesterase (EC 3.1.4.1) was purified to homogeneity from the fruit body of Flammulina velutipes. The enzyme had considerable activity toward oligonucleotides. The Km values were 0.66 mM for ApA, 2.47 mM for (Ap)2A, and 3.03 mM for (Ap)3A. The enzyme hydrolyzed oligodeoxyribonucleotides as well as oligoribonucleotides. The oligoribonucleotides bearing a phosphate residue at the 3' end were not hydrolyzed by the enzyme. The enzyme hydrolyzed the oligoribonucleotides exonucleolytically from the 3' to 5' end. Thus the PDase of F. velutipes is considered to function in vivo as an oligonucleotidase (EC 3.1.13.3), which efficiently converts oligonucleotides to 5'-mononucleotides in the cell.

Calmodulin, a calcium-dependent modulator protein, is known to mediate a great number of Ca++-dependent processes in various tissues. Although it was originally described as a protein activator of cyclic nucleotide phosphodiesterase, the sensitivity of phosphodiesterases to this compound are suggested to be variable from tissue to tissue. In order to determine whether there was calmodulin-like activity in pig skin epidermis and to see its relationship to epidermal phosphodiesterase, we used an established calmodulin deficient phosphodiesterase system prepared from bovine heart. Calmodulin deficient phosphodiesterase prepared from bovine heart was markedly stimulated by the addition of pig skin (epidermal) boiled extract in the presence of calcium. Boiled skin extract alone had only little phosphodiesterase activity by itself. This effect of boiled skin extract on bovine heart phosphodiesterase was inhibited by the addition of EGTA, a divalent metal ion chelator of relative Ca++ specificity. At a fixed concentration of EGTA, increasing the Ca++ concentration counteracted the effect of EGTA. Pure pig skin epidermis (separated by trypsinization, NaBr, CaCl2-sucrose or NH4Cl treatment) was also shown to have heat-stable calmodulin activity. In contrast to the bovine heart phosphodiesterase, epidermal phosphodiesterase was only partially inhibited when Ca++ was removed by EGTA. The addition of boiled skin extract on the crude extract of epidermal phosphodiesterase had minimal effect on the enzyme activity. Overall results indicate that although pig skin epidermis contains significant amount of calmodulin, the regulation of phosphodiesterase may not be the main biological activity of epidermal calmodulin.