Effects of organ dose modulation applied to a part of the scan range on radiation dose in computed tomography of the body.

In computed tomography (CT), organ dose modulation (ODM) reduces radiation exposure from the anterior side to reduce radiation dose received by the radiosensitive organs located anteriorly. We investigated the effects of ODM applied to a part of the scan range on radiation dose in body CT. The thorax and thoraco-abdominopelvic region of an anthropomorphic whole-body phantom were imaged with and without ODM. ODM was applied to various regions, and the tube current modulation curves were compared. Additionally, the dose indices were compared with and without ODM in thoracic and thoraco-abdominopelvic CTs in 800 patients. ODM was applied to the thyroid in male patients and to the thyroid and breast in female patients. In phantom imaging of the thorax, the application of ODM below the scan range decreased the tube current, and that to the breast showed a further decrease. Decreased tube current was also observed in phantom imaging of the thoraco-abdominopelvic regions with ODM below the scan range, and the application of ODM to the whole scan range, thyroid, breast, and both thyroid and breast further reduced the tube current in the region to which ODM was applied. In patient imaging, the dose indices were significantly lower with ODM than without ODM, regardless of the scan range or sex. The absolute reduction in dose-length product was larger for thoraco-abdominopelvic CT (male, 43.2 mGy cm; female, 59.7 mGy cm) than for thoracic CT (male, 30.8 mGy cm; female, 37.6 mGy cm) in both sexes, indicating dose reduction in the abdominopelvic region to which ODM was not applied. In conclusion, The application of ODM in body CT reduces radiation dose not only in the region to which ODM is applied but also outside the region. In radiation dose management, it should be considered that even ODM applied to a limited region affects the dose indices.

Intracranial Neurofeedback Modulating Neural Activity in the Mesial Temporal Lobe During Memory Encoding: A Pilot Study.

Removal of the mesial temporal lobe (MTL) is an established surgical procedure that leads to seizure freedom in patients with intractable MTL epilepsy; however, it carries the potential risk of memory damage. Neurofeedback (NF), which regulates brain function by converting brain activity into perceptible information and providing feedback, has attracted considerable attention in recent years for its potential as a novel complementary treatment for many neurological disorders. However, no research has attempted to artificially reorganize memory functions by applying NF before resective surgery to preserve memory functions. Thus, this study aimed (1) to construct a memory NF system that used intracranial electrodes to feedback neural activity on the language-dominant side of the MTL during memory encoding and (2) to verify whether neural activity and memory function in the MTL change with NF training. Two intractable epilepsy patients with implanted intracranial electrodes underwent at least five sessions of memory NF training to increase the theta power in the MTL. There was an increase in theta power and a decrease in fast beta and gamma powers in one of the patients in the late stage of memory NF sessions. NF signals were not correlated with memory function. Despite its limitations as a pilot study, to our best knowledge, this study is the first to report that intracranial NF may modulate neural activity in the MTL, which is involved in memory encoding. The findings provide important insights into the future development of NF systems for the artificial reorganization of memory functions.

[The Safety of Bladder Irrigation with Solution G Prepared with Tap Water].

This study investigated the safety of bladder irrigation in patients with indwelling bladder catheter using Solution G prepared with tap water. Solution G was prepared using tap water and stored in a refrigerator for 1 week. The bacterial count range in the solution was estimated to be between 0 and 10 colony forming units/ml. The values were within the reference range in the Water Supply Act of Japan. Subsequently, bladder irrigation was performed with the prepared Solution G in six patients. The number of bacteria, leukocytes, and bacterial flora were evaluated before and 1 and 3 months after bladder irrigation. The results indicated no significant change in the values during this period. Therefore, bladder irrigation with Solution G prepared with tap water is safe.

Usefulness of model-based iterative reconstruction in low-dose lumbar spine CT after spine surgery with metal implant: a phantom study.

BACKGROUND: The major problems of computed tomography (CT) imaging include radiation exposure and severe artifacts caused by operative implants. PURPOSE: To evaluate the usefulness of the metal artifact reduction algorithm and model-based iterative reconstruction (MBIR) in postoperative low-dose (LD) spine CT. MATERIAL AND METHODS: A CT torso phantom was scanned at standard-dose (SD) and LD settings. The CT images were reconstructed by three methods: hybrid iterative reconstruction (HIR); metal artifact reduction; and MBIR. The radiation dose of the phantom imaging was evaluated by volume CT dose index (mGy), dose length product (DLP, mGy × cm), and effective dose (mSv). The image quality of the six images was visually evaluated and analyzed using Scheffe's paired comparison method. The average preference of each method was calculated based on the comparative scores. The task transfer function (TTF) and noise power spectrum for HIR and MBIR were also measured. RESULTS: The respective radiation-dose-related parameters of the SD and LD conditions were: volume CT dose index = 10.2 and 1.2 mGy; DLP = 277.9 and 33.9 mGy × cm; and effective dose = 4.2 and 0.5 mSv. The average preference for diagnostic acceptability of MBIR at LD was not significantly different from the other reconstructions of SD data. MBIR successfully reduced metal artifacts in the LD condition. The 10% TTF was higher for HIR at SD and higher for MBIR at LD. CONCLUSION: MBIR is useful for LD spine CT after spine surgery with metal implant.

Cervical spinal computed tomography utilizing model-based iterative reconstruction reduces radiation to an equivalent of three cervical X-rays.

PURPOSE: To evaluate radiation dose and image quality of cervical spinal computed tomography scanned with low-radiation dose (LD-CT) utilizing model-based iterative reconstruction (MBIR). METHODS: We retrospectively examined 14 patients (65.5 ± 13.9 years) who underwent both standard-radiation-dose CT (SD-CT) reconstructed with hybrid iterative reconstruction and LD-CT of cervical spine. The radiation dose, objective image quality indicator, which includes signal-to-noise and contrast-to-noise, and subjective image quality score of the anatomical landmarks in the SD-CT and LD-CT were statistically compared. In addition, the measurement errors of the length of C3 vertebrae (height, anteroposterior length, inner and outer pedicle diameters) between SD-CT and LD-CT were analyzed. RESULTS: Radiation dose of LD-CT was reduced to one-sixth of the dose of SD-CT. The objective image quality indicator of LD-CT was significantly better than that of SD-CT. The subjective image quality of LD-CT was relatively worse than that of SD-CT but generally graded as clinically accepted or higher. There was no remarkable difference between SD-CT and LD-CT in the measurement value of height and anteroposterior length. Inner pedicle diameter was significantly (0.21 ± 0.13 mm) smaller, and outer pedicle diameter was (0.24 ± 0.14 mm) larger on LD-CT than on SD-CT. CONCLUSION: Cervical spinal LD-CT that utilized MBIR enabled radical decrease in radiation dose and provided sufficient image quality for clinical use. This scanning protocol can be a good alternative for protecting patients from exposure to unnecessary radiation, especially when a patient requires multiple CT scans.

Real-time surveillance of left atrial appendage thrombus during contrast computed tomography imaging for catheter ablation: THe Reliability of cOMputed tomography Beyond UltraSound in THROMBUS detection (THROMBUS) study.

Left atrial contrast computed tomography (LA-CT) as well as transesophageal echocardiography (TEE) can exclude left atrial appendage (LAA) thrombus, but is sometimes unable to evaluate LAA due to incomplete LAA filling. The aim of the current study was to validate the utility of real-time approach of LA-CT with real-time surveillance of LAA-filling defect (FD). We enrolled consecutive 894 patients with LA-CT studies acquired for catheter ablation and compared the diagnostic accuracy in demonstrating LAA-FD between conventional protocol (N = 474) and novel protocol with real-time surveillance of LAA-FD immediately after the initial scanning and, when necessary, adding delayed scanning in the supine or prone position (N = 420). Primary endpoint was severity of LAA-FD classified into the 3 groups: "Grade-0" for complete filling of contrast, "Grade-1" for incomplete filling of contrast, and "Grade-2" for complete FD of contrast. The prevalence of Grade-1 and Grade-2 FD was 17.3% and 11.2% in conventional protocol, whereas there was no patient with Grade-2 FD, and only 1 patient with Grade-1 FD after the additional scanning in novel protocol. In 5 patients with suspected LAA thrombus both by TEE and Grade-2 FD in LA-CT by the conventional protocol, ablation procedure was canceled due to diagnosis of LAA thrombus. Conversely, 4 patients with suspected LAA thrombus by TEE in novel protocol group was proved to have intact LAA by LA-CT with and without additional scanning. This novel approach with real-time surveillance improved the diagnostic accuracy of LA-CT in detecting LAA-FD, suggesting potential superiority of LA-CT over TEE in excluding LAA thrombus.

Identification of SHRUBBY, a SHORT-ROOT and SCARECROW interacting protein that controls root growth and radial patterning.

The timing and extent of cell division is particularly important for the growth and development of multicellular organisms. Roots of the model organism Arabidopsis thaliana have been widely studied as a paradigm for organ development in plants. In the Arabidopsis root, the plant-specific GRAS family transcription factors SHORT-ROOT (SHR) and SCARECROW (SCR) are key regulators of root growth and of the asymmetric cell divisions that separate the ground tissue into two separate layers: the endodermis and cortex. To elucidate the role of SHR in root development, we identified 17 SHR-interacting proteins. Among those isolated was At5g24740, which we named SHRUBBY (SHBY). SHBY is a vacuolar sorting protein with similarity to the gene responsible for Cohen syndrome in humans. Hypomorphic alleles of shby caused poor root growth, decreased meristematic activity and defects in radial patterning that are characterized by an increase in the number of cell divisions in the ground tissue that lead to extra cells in the cortex and endodermis, as well as additional cell layers. Analysis of genetic and molecular markers indicates that SHBY acts in a pathway that partially overlaps with SHR, SCR, PLETHORA1 and PLETHORA2 (PLT1 and PLT2). The shby-1 root phenotype was partially phenocopied by treatment of wild-type roots with the proteosome inhibitor MG132 or the gibberellic acid (GA) synthesis inhibitor paclobutrazol (PAC). Our results indicate that SHBY controls root growth downstream of GA in part through the regulation of SHR and SCR.

Evaluation of Tumor-associated Stroma and Its Relationship with Tumor Hypoxia Using Dynamic Contrast-enhanced CT and (18)F Misonidazole PET in Murine Tumor Models.

PURPOSE: To determine the relationship between the fractional interstitial volume (Fis), as calculated at dynamic contrast material-enhanced (DCE) computed tomography (CT), and tumor-associated stroma and to analyze its spatial relationship with tumor hypoxia in several xenograft tumor models. MATERIALS AND METHODS: All animal experiments were approved by the animal research committee. Mice with three different xenograft tumors (U251, CFPAC-1, and BxPC-3; n = 6, n = 8, and n = 6, respectively) underwent DCE CT then hypoxia imaging with fluorine 18 ((18)F) fluoromisonidazole (FMISO) positron emission tomography (PET) within 24 hours. Immunohistochemical analysis was performed in harvested tumors to detect hypoxia markers and to quantify microvascular and stromal density. Two DCE CT parameters (amount of interstitial space associated with the amount of stroma [Fis] and flow velocity [Fv]) were identified and quantitatively validated by using immunohistochemistry. FMISO uptake within the tumor was also assessed in relation to DCE CT parameters. Imaging and immunohistochemical parameters were assessed by using the Kruskal-Wallis test, Wilcoxon rank-sum test with Bonferroni correction, and Pearson correlation coefficient. RESULTS: Almost no α-smooth muscle actin-positive cells were found in the U251 xenograft, while abundant stroma was found in the entire BxPC-3 xenograft and in the periphery of the CFPAC-1 xenograft. Quantitative analysis showed a significant correlation (R = 0.83, P < .0001) between Fis and stromal density. FMISO uptake had a negative correlation with Fis (R = -0.58, P < .0001) and Fv (R = -0.53, P < .0001). CONCLUSION: DCE CT can be used to quantify parameters associated with tumor-associated stroma. Tumor hypoxia was Complementarily localized in tumor-associated stroma in these models.

The SHORT-ROOT protein acts as a mobile, dose-dependent signal in patterning the ground tissue.

A key question in developmental biology is how cellular patterns are created and maintained. During the formation of the Arabidopsis root, the endodermis, middle cortex (MC), and cortex are produced by periclinal cell divisions that occur at different positions and at different times in root development. The endodermis and cortex arise continuously from the periclinal divisions of cells that surround the quiescent center (QC) at the tip of the root. The MC arises between days 7 and 14 from periclinal divisions of the endodermis. The divisions that produce the middle cortex begin in the basal region of the root meristem away from the QC and then spread apically and circumferentially around the root. Although the transcription factor SHORT-ROOT (SHR) is required for both of these divisions, the mechanism that determines where and when SHR acts to promote cell division along the longitudinal axis of the root is unknown; SHR is present along the entire length of the root tip, but only promotes periclinal divisions at specific sites. Here we show that the abundance of the SHR protein changes dynamically as the root develops, and that the pattern of cell division within the endodermis is sensitive to the dose of this protein: high levels of SHR prevent the formation of the MC, whereas intermediate levels of SHR promote MC formation. These results provide a mechanism for the longitudinal patterning of the endodermis, and represent the first example in plants of a mobile transcription factor whose function (activator or repressor) depends upon concentration.

[Case report : bleeding from ileal conduit in a patient with portal hypertension due to liver cirrhosis type C].

A 68-year-old man treated for type C liver cirrhosis was referred to our hospital for evaluation of a bladder tumor. The patient underwent transurethral resection of bladder tumor. The histopathological diagnosis was urothelial cancer (G2>G3, T2) and he underwent radical cystectomy with ileal conduit urinary diversion. Starting 3 months postoperatively, he experienced bleeding from the mucosa of the ileal conduit. Computed tomography showed vascular dilatation around the ileal conduit. This was considered to be attributable to portal hypertension resulting from liver cirrhosis. Conservative therapy failed to achieve hemostasis. The patient was not considered to have indications for a transjugular intrahepatic portosystemic shunt (TIPS). He died from bleeding 22 months after radical cystectomy.

[A case report: a patient with paralysis of the lower half of the body being diagnosed with prostate cancer and primary spinal malignant lymphoma].

The patient was an 81-year-old man who visited our hospital for paralysis of the lower half of the body. He was suspected as having a spinal tumor by computed tomography and magetic resonance imaging, and also as having prostate cancer based on a high prostate specific antingen level. A prostate needle biopsy, thoracic spinal fusion and posterior decompression were performed. The patient was diagnosed as having prostate cancer and primary spinal malignant lymphoma. Hormone therapy and chemotherapy were started for the prostate cancer and primary spinal malignant lymphoma, respectively. However, the patient died of a complication from chemotherapy.

[Two cases of lower abdominal tumors difficult to differentiate from urachal tumors].

CASE 1: A 28-year-old woman visited a local medical doctor, complaining of abdominal pain, urinary frequency and a sense of residual urine. Magnetic resonance imaging revealed a lower abdominal extraperitoneal tumor, approximately 5 cm in diameter, adjacent to the bladder dome. It was thought to be a urachal tumor, and she was referred to our hospital. A hard hen's egg-sized mass was palpable in the lower abdomen. Urinary analysis was normal. Cytological examination was also negative. Cystoscopy revealed redness in the bladder dome mucosa. Although the preoperative diagnosis was a urachal cancer, the pathological diagnosis on surgery was desmoids, and tumor excision was performed. No recurrence has been seen for 7 years postoperatively. CASE 2: A 71-year-old man complaining of swelling of the lower abdomen was referred to our department because he was suspected to have a urachal tumor, of about 15 cm in diameter, on computed tomography. A hard infant head-sized mass was palpable in the lower abdomen. Urinary analysis was normal. Cystoscopical examination showed a markedly compressed bladder dome, however, no abnormal findings were seen in the mucosa. Although the preoperative diagnosis was a urachal tumor, the intraoperative pathological diagnosis revealed no malignancy. The mass was connected to the bladder dome, and partial cystectomy was conducted. The final pathological diagnosis was a solitary fibrous tumor. No recurrence has been seen for 5 years postoperatively. Because a urachal tumor is highly malignant, radical cystectomy and urinary diversion might be planned preoperatively. However, care should be taken not to be too invasive, considering the possibility of a benign tumor.

Spatial distribution of three ARGONAUTEs regulates the anther phasiRNA pathway.

Argonaute protein (AGO) in association with small RNAs is the core machinery of RNA silencing, an essential mechanism for precise development and defense against pathogens in many organisms. Here, we identified two AGOs in rice anthers, AGO1b and AGO1d, that interact with phased small interfering RNAs (phasiRNAs) derived from numerous long non-coding RNAs. Moreover, 3D-immunoimaging and mutant analysis indicated that rice AGO1b and AGO1d cell type-specifically regulate anther development by acting as mobile carriers of these phasiRNAs from the somatic cell layers to the germ cells in anthers. Our study also highlights a new mode of reproductive RNA silencing via the specific nuclear and cytoplasmic localization of three AGOs, AGO1b, AGO1d, and MEL1, in rice pollen mother cells.

Paving the Way for Memory Enhancement: Development and Examination of a Neurofeedback System Targeting the Medial Temporal Lobe.

Neurofeedback (NF) shows promise in enhancing memory, but its application to the medial temporal lobe (MTL) still needs to be studied. Therefore, we aimed to develop an NF system for the memory function of the MTL and examine neural activity changes and memory task score changes through NF training. We created a memory NF system using intracranial electrodes to acquire and visualise the neural activity of the MTL during memory encoding. Twenty trials of a tug-of-war game per session were employed for NF and designed to control neural activity bidirectionally (Up/Down condition). NF training was conducted with three patients with drug-resistant epilepsy, and we observed an increasing difference in NF signal between conditions (Up-Down) as NF training progressed. Similarities and negative correlation tendencies between the transition of neural activity and the transition of memory function were also observed. Our findings demonstrate NF's potential to modulate MTL activity and memory encoding. Future research needs further improvements to the NF system to validate its effects on memory functions. Nonetheless, this study represents a crucial step in understanding NF's application to memory and provides valuable insights into developing more efficient memory enhancement strategies.

3D Imaging and In Situ Hybridization for Uncovering the Functions of MicroRNA in Rice Anther.

Small RNAs specifically expressed in reproductive tissues are key regulators of germline development in eukaryotes. Rice microRNA2118 (miR2118), which is enriched during reproduction in grasses, is a trigger to produce phased small interfering RNAs (phasiRNAs). These phasiRNAs demonstrate the temporal regulation with premeiotic phasiRNAs and meiotic phasiRNAs in anther development. Furthermore, the site-specific regulation via miR2118 and phasiRNAs is of importance in soma and germ development in anthers. Accordingly, histological imaging methods are essential tools for understanding spatiotemporal regulation during reproduction and elucidating the reproductive roles of miRNAs and phasiRNAs. We successfully developed a method to visualize the three-dimensional (3D) structure of entire rice anthers, which can also be used for distinguishing the internal structure of the anthers in other plants. Here, we describe the detailed methods of in situ hybridization for miR2118 localization and the visualization of the 3D structure of entire anthers of rice.

Deep learning-based reconstruction of chest ultra-high-resolution computed tomography and quantitative evaluations of smaller airways.

The full-iterative model reconstruction generates ultra-high-resolution computed tomography (U-HRCT) images comprising a 1024 × 1024 matrix and 0.25 mm thickness while suppressing image noises, allowing evaluating small airways 1-2 mm in diameter. However, this technique imposes huge computational burdens and requires a long reconstruction time. This study evaluated whether a recently-established deep learning-based reconstruction, Advanced intelligent Clear-IQ Engine (AiCE), allows quantitative morphological analyses of smaller airways with equal or better quality than the full-iterative model reconstruction while shortening the reconstruction time. In phantom tubes mimicking small airways, the measurement error of 0.5-mm-thickness wall was smaller on the AiCE-based than the full-iterative model-based U-HRCT. Moreover, in five patients with chronic obstructive pulmonary disease, the AiCE-based U-HRCT decreased the reconstruction time approximately by 90% with a modest improvement in image noise, contrast, and sharpness compared to the full-iterative model-based U-HRCT. Therefore, the AiCE-based U-HRCT can be readily used clinically for morphologically evaluating peripheral small airways.

Associations of pulmonary and extrapulmonary computed tomographic manifestations with impaired physical activity in symptomatic patients with chronic obstructive pulmonary disease.

In patients with chronic obstructive pulmonary disease (COPD), emphysema, airway disease, and extrapulmonary comorbidities may cause various symptoms and impair physical activity. To investigate the relative associations of pulmonary and extrapulmonary manifestations with physical activity in symptomatic patients, this study enrolled 193 patients with COPD who underwent chest inspiratory/expiratory CT and completed COPD assessment test (CAT) and the Life-Space Assessment (LSA) questionnaires to evaluate symptom and physical activity. In symptomatic patients (CAT ≥ 10, n = 100), emphysema on inspiratory CT and air-trapping on expiratory CT were more severe and height-adjusted cross-sectional areas of pectoralis muscles (PM index) and adjacent subcutaneous adipose tissue (SAT index) on inspiratory CT were smaller in those with impaired physical activity (LSA < 60) than those without. In contrast, these findings were not observed in less symptomatic patients (CAT < 10). In multivariable analyses of the symptomatic patients, severe air-trapping and lower PM index and SAT index, but not CT-measured thoracic vertebrae bone density and coronary artery calcification, were associated with impaired physical activity. These suggest that increased air-trapping and decreased skeletal muscle and subcutaneous adipose tissue quantity are independently associated with impaired physical activity in symptomatic patients with COPD.

[A case report: small cell carcinoma of the ureter].

An 82-year-old woman visited our hospital with right flank pain. Computed tomography showed a right ureteral tumor. Urine cytology was class IV and cystoscopy demonstrated no obvious lesion. We performed right total nephroureterectomy and histopathological diagnosis was small cell carcinoma of the ureter. The serum ProGRP was slightly elevated postoperatively. Positron emission tomography showed a distant metastasis to the third lumber vertebra. She received two courses of chemotherapy (cisplatin and etoposide) and radiation therapy (8 Gy), but the distant metastasis was progressive. She died 6 months postoperatively.

Influence of Asthma Onset on Airway Dimensions on Ultra-high-resolution Computed Tomography in Chronic Obstructive Pulmonary Disease.

PURPOSE: Asthma onset before the age of 40 years is associated with distinct clinical manifestations in chronic obstructive pulmonary disease (COPD) patients, but its morphologic features remain unestablished. This study aimed to explore airway morphology in COPD patients with asthma onset before 40 years of age using ultra-high-resolution computed tomography (U-HRCT), which allows a more accurate quantitation of the lumen and the wall in smaller airways than using conventional CT. MATERIALS AND METHODS: Clinical data of 500 consecutive patients undergoing full inspiratory U-HRCT (1024×1024 matrix and 0.25 mm slice thickness) were retrospectively analyzed. COPD patients without asthma, COPD patients with asthma onset at age below or 40 years and above, and non-COPD smoker controls (N=137, 29, 34, and 22, respectively) were enrolled. The length, lumen area (LA), wall thickness and area (WA), and wall area percent (WA%) of the segmental (third-generation) to sub-subsegmental (fifth-generation) bronchus and the low attenuation volume percent (LAV%) were measured. RESULTS: LA and WA were smaller in the fourth and fifth generation in COPD patients than in non-COPD controls, regardless of the age of asthma onset. LA was smaller and WA% was larger in the fourth-generation and fifth-generation airways in COPD with asthma onset before 40 years than COPD without asthma, whereas WA did not differ between them. In multivariate analyses, asthma onset before 40 years was associated with smaller LA in COPD patients independent of demographics, use of inhaled corticosteroids and long-acting bronchodilators, airflow limitation, and LAV%. CONCLUSIONS: Asthma onset before 40 years of age could be associated with greater lumen narrowing of the airways in COPD.

Color morphs of the coral, Acropora tenuis, show different responses to environmental stress and different expression profiles of fluorescent-protein genes.

Corals of the family Acroporidae are key structural components of reefs that support the most diverse marine ecosystems. Due to increasing anthropogenic stresses, coral reefs are in decline. Along the coast of Okinawa, Japan, three different color morphs of Acropora tenuis have been recognized for decades. These include brown (N morph), yellow green (G), and purple (P) forms. The tips of axial polyps of each morph exhibit specific fluorescence spectra. This attribute is inherited asexually, and color morphs do not change seasonally. In Okinawa Prefecture, during the summer of 2017, N and P morphs experienced bleaching, in which many N morphs died. Dinoflagellates (Symbiodiniaceae) are essential partners of scleractinian corals, and photosynthetic activity of symbionts was reduced in N and P morphs. In contrast, G morphs successfully withstood the stress. Examination of the clade and type of Symbiodiniaceae indicated that the three color-morphs host similar sets of Clade-C symbionts, suggesting that beaching of N and P morphs is unlikely attributable to differences in the clade of Symbiodiniaceae the color morphs hosted. Fluorescent proteins play pivotal roles in physiological regulation of corals. Since the A. tenuis genome has been decoded, we identified five genes for green fluorescent proteins (GFPs), two for cyan fluorescent proteins (CFPs), three for red fluorescent proteins (RFPs), and seven genes for chromoprotein (ChrP). A summer survey of gene expression profiles under outdoor aquarium conditions demonstrated that (a) expression of CFP and REP was quite low during the summer in all three morphs, (b) P morphs expressed higher levels of ChrP than N and G morphs, (c) both N and G morphs expressed GFP more highly than P morphs, and (d) GFP expression in N morphs was reduced during summer whereas G morphs maintained high levels of GFP expression throughout the summer. Although further studies are required to understand the biological significance of these color morphs of A. tenuis, our results suggest that thermal stress resistance is modified by genetic mechanisms that coincidentally lead to diversification of color morphs of this coral.