Delineation of the internal iliac vein using MRI with true FISP sequence in patients with locally recurrent rectal cancer: A pilot study using CT/MRI fusion.

PURPOSE: This study assessed the feasibility of using three-dimensional (3D) models of intrapelvic vascular patterns constructed using computed tomography (CT) and magnetic resonance imaging (MRI) fusion data for preoperative planning in patients with locally recurrent rectal cancer. METHODS: Eleven patients scheduled for pelvic exenteration were included. The 3D fusion data of the intrapelvic vessels constructed using CT and MRI with true fast imaging with steady-state precession sequence (True FISP) were evaluated preoperatively. Contrast ratios (CR) between the piriformis muscle and the intrapelvic vessels were calculated to identify a valid modality for 3D modeling and creating CT/MRI fusion-reconstructed volume-rendered images. RESULTS: The CR values of the internal and external iliac arteries were significantly higher on CT images than MR images (CT vs. MRI; 0.63 vs. 0.45, p < 0.01). However, the CR value of the internal iliac vein was significantly higher on MR than CT images (CT vs. MRI; 0.23 vs. 0.55, p < 0.01). CONCLUSIONS: MRI with True FISP yielded high signal-to-noise ratios and aided in delineating the internal iliac vein around the piriformis muscle. More precise 3D models can be constructed using this technique in the future to aid in the resection of locally recurrent rectal cancer.

The Impacts of Laparoscopic Restorative Proctocolectomy for Ulcerative Colitis: Systematic Review and Meta-Analysis.

Introduction: Laparoscopic surgery (LAP) is now recognized as the standard procedure for colorectal surgery. However, the standard surgery for ulcerative colitis (UC) is total proctocolectomy with ileal pouch anal anastomosis (IPAA), which may be an overly complex procedure to complete laparoscopically. We conducted this systematic review and meta-analysis to evaluate the efficacy as well as the advantages and disadvantages of LAP-IPAA in patients with UC stratified by the outcome of interest. Method: We performed a systematic literature review by searching the PubMed/MEDLINE, the Cochrane Library, and the Japan Centra Reuvo Medicina databases from inception until January 2023. Meta-analyses were performed for surgical outcomes, including morbidity and surgical course, to evaluate the efficacy of LAP-IPAA. Results: A total of 707 participants, including 341 LAP and 366 open surgery (OPEN) patients in 9 observational studies and one randomized controlled study, were included. From the results of the meta-analyses, the odds ratio (OR) of total complications in LAP was 1.12 (95% CI: 0.58-2.17, p = 0.74). The OR of mortality for LAP was 0.38 (95% CI: 0.08-1.92, p = 0.24). Although the duration of surgery was extended in LAP (mean difference (MD) 118.74 min (95% CI: 91.67-145.81), p < 0.01) and hospital stay were not shortened, the duration until oral intake after surgery was shortened in LAP (MD -2.10 days (95% CI: -3.52-0.68), p = 0.004). Conclusions: During IPAA for UC, a similar morbidity rate was seen for LAP and OPEN. Although LAP necessitates extended surgery, there may be certain advantages to this procedure, including easy visibility during the surgical procedure or a shortened time to oral intake after surgery.

Delivery catheter system carries more physiological right ventricular septal pacing than stylet system.

INTRODUCTION: The Mt. FUJI multicenter trial demonstrated that a delivery catheter system had a higher rate of successful right ventricular (RV) lead deployment on the RV septum (RVS) than a conventional stylet system. In this subanalysis of the Mt. FUJI trial, we assessed the differences in electrocardiogram (ECG) parameters during RV pacing between a delivery catheter system and a stylet system and their associations with the lead tip positions. METHODS: Among 70 patients enrolled in the Mt FUJI trial, ECG parameters, RV lead tip positions, and lead depth inside the septum assessed by computed tomography were compared between the catheter group (n = 36) and stylet group (n = 34). RESULTS: The paced QRS duration (QRS-d), corrected paced QT (QTc), and JT interval (JTc) were significantly shorter in the catheter group than in the stylet group (QRS-d: 130 ± 19 vs. 142 ± 15 ms, p = .004; QTc: 476 ± 25 vs. 514 ± 20 ms, p < .001; JTc: 347 ± 24 vs. 372 ± 17 ms, p < .001). This superiority of the catheter group was maintained in a subgroup analysis of patients with an RV lead tip position at the septum. The lead depth inside the septum was greater in the catheter group than in the stylet group, and there was a significant negative correlation between the paced QRS-d and the lead depth. CONCLUSION: Using a delivery catheter system carries more physiological depolarization and repolarization during RVS pacing and deeper screw penetration in the septum in comparison to conventional stylet system. The lead depth could have a more impact on the ECG parameters rather than the type of pacing lead.

Characterization and organelle genome sequencing of Pyropia species from Myanmar.

Pyropia is a genus comprising red algae of the Bangiaceae family that is commonly found in intertidal zones worldwide. However, understanding of Pyropia species that are prone to tropical regions remains limited despite recent breakthroughs in genomic research. Within the realm of Pyropia species thriving in tropical regions, P. vietnamensis stands out as a widely recognized species. In this study, we aimed to investigate Pyropia species in the southwest coast of Myanmar using physiological and molecular approaches, culture-based analyses, chloroplast rbcL and nuclear SSU gene sequencing, and whole chloroplast and mitochondrial genome sequencing. Physiological analysis showed that the Myanmar samples were more heat-tolerant than their Japanese counterparts, including those of subtropical origin. Additionally, molecular characterization revealed that the Myanmar samples were closely related to P. vietnamensis from India. This study is the first to sequence the chloroplast and mitochondrial genomes of Pyropia species from tropical regions. A unique deletion event was observed within a ribosomal RNA gene cluster in the chloroplast genome of the studied Pyropia species, which is a deviation from the usual characteristics of most Pyropia species. This study improves current understanding of the physiological and molecular characteristics of this comparatively understudied Pyropia species that grows in tropical regions.

[Questionnaire Survey on the Timing of Comprehensive Genomic Profiling for Advanced Recurrent Colorectal Cancer and Its Impact on Patients].

BACKGROUNDS: Comprehensive genomic profiling(CGP)has been covered by health insurance since June 2019. However, the clinical impact of CGP on patients with metastatic colorectal cancer(mCRC)remains unclear. To date, there are very limited reports regarding patient-oriented outcomes of CGP in mCRC. PATIENTS: A questionnaire was completed by patients with mCRC who had already received their CGP results after April 2021. Eight questions were posed, covering the degree of satisfaction and timing when CGP was conducted. RESULTS: Of the 51 patients with mCRC who had received their CGP test results by August 2021 in our department, 21 patients responded to our questionnaire. In total 66.7% patients with mCRC answered "(very)satisfied"with the CGP testing. 28.6% of the patients already knew about CGP testing before their local doctors informed them. Except for 3 patients who did not answer, 47.6% and 9.5% of patients with mCRC"agreed"and "moderately agreed"with the timing of the CGP test. CONCLUSION: Although most patients with mCRC failed to access promising new treatment via CGP, approximately half of the patients answered that they were satisfied with the CGP testing. Conversely, a few patients already knew about CGP testing before it was proposed by their doctors. Thus, the provision of information at an early stage is necessary.

Clinical features and surgical selection in colitis-associated colorectal cancer with ulcerative colitis.

PURPOSE: The aim of this study was to compare the clinical characteristics of ulcerative colitis (UC) patients who underwent surgery for cancer/dysplasia with those who underwent surgery for refractory disease and to discuss the preoperative preparation for successful hand-sewn IPAA. METHODS: Patients who underwent surgery for UC between January 2014 and December 2021 at Hyogo Medical University were included in the study. A total of 443 UC surgical cases were included in the study, which comprised 188 cancer/dysplasia patients and 255 refractory patients. Clinical records were compared retrospectively. RESULTS: The proportion of surgical UC cases with cancer/dysplasia has been on the rise, accounting for approximately 40% in recent years. The duration of disease (months) was 186 (2-590) in the cancer/dysplasia group and 48 (1-580) in the refractory group (p = 0.02). UC severity (mild/moderate/severe) was 119/69/0 in the cancer/dysplasia group and 18/157/80 in the refractory group (p < 0.01). The four nutrition factors of weight (55.2 (32.7-99.6) kg: 49.9 (20.3-85.2) kg), body mass index (21.0 (13.9-32.5) kg/m2: 18.3 (11.4-34.1)kg/m2), serum albumin level (4.3 (2.7-5.0)g/dl: 3.4 (1.4-5.2)g/dl) and prognostic nutrition index (49.2 (33.2-61.2): 40.9 (17.4-61.1)) were significantly higher in the cancer/dysplasia group (p < 0.01). The degree of obesity was also significantly higher in the cancer/dysplasia group (p < 0.01). CONCLUSION: UC patients with cancer/dysplasia were more likely than refractory patients to have mild inflammation; they also had a longer duration of UC disease and better nutritional status.

A mosaic adeno-associated virus vector as a versatile tool that exhibits high levels of transgene expression and neuron specificity in primate brain.

Recent emphasis has been placed on gene transduction mediated through recombinant adeno-associated virus (AAV) vector to manipulate activity of neurons and their circuitry in the primate brain. In the present study, we created a novel vector of which capsid was composed of capsid proteins derived from both of the AAV serotypes 1 and 2 (AAV1 and AAV2). Following the injection into the frontal cortex of macaque monkeys, this mosaic vector, termed AAV2.1 vector, was found to exhibit the excellence in transgene expression (for AAV1 vector) and neuron specificity (for AAV2 vector) simultaneously. To explore its applicability to chemogenetic manipulation and in vivo calcium imaging, the AAV2.1 vector expressing excitatory DREADDs or GCaMP was injected into the striatum or the visual cortex of macaque monkeys, respectively. Our results have defined that such vectors secure intense and stable expression of the target proteins and yield conspicuous modulation and imaging of neuronal activity.

Anatomical Validation of Internal Iliac Vessels Assessed by Three-dimensional Angiographic Analysis.

Objectives: Anatomical understanding of the internal iliac vessels is important with the increasing frequency of minimally-invasive pelvic surgery. We aimed to investigate the branch patterns of internal iliac vessels, especially the veins. Methods: This study included 30 patients with 60 half-pelvises who underwent minimally-invasive pelvic surgery. Branch patterns were assessed on surgical videos with a multi-detector computed tomography-based three-dimensional simulation. Branch patterns of the superior gluteal artery and vein (SGA and SGV), inferior gluteal artery and vein (IGA and IGV), internal pudendal artery and vein (IPA and IPV), and obturator artery and vein (ObA and ObV) were investigated. Results: In the most frequent internal iliac vein (IIV) branch pattern, 67% of SGV branched from the IIV, 95% of the IGV branched from the IPV and 82% of the ObV branched from the IPV. According to Adachi's classification, 62% of IIVs were Type I and 33% Type IV. Although IIV branch patterns are heterogeneous, in individual patients with the most frequent branch patterns, good correlation (75-100%) of the branch patterns was observed between the internal iliac artery (IIA) and IIV, and between the right and left IIVs. Conclusions: This study clarified the branch patterns of IIV. In patients with the most frequent branch patterns, good correlation of the branch patterns was observed between the IIA and IIV, and between right and left IIV. We believe this helps secure the safety and standardization of minimally-invasive pelvic surgery.

Transanal Minimally Invasive Surgical Approach to Total Pelvic Exenteration.

BACKGROUND: Total pelvic exenteration, a surgical procedure for patients with highly advanced primary and recurrent rectal cancer, is technically demanding. IMPACT OF INNOVATION: We report the utility of a transanal minimally invasive surgical approach to total pelvic exenteration. TECHNOLOGY MATERIALS AND METHODS: A 2-team approach with a laparoscopic transabdominal approach and transanal minimally invasive surgery was adopted. During the transabdominal approach in the pelvis, dissection was performed to remove the pelvic organs and visceral branches of the internal iliac vessels. The dissection goal via the transabdominal approach is the levator ani. During the transperineal approach, dissection is performed along the levator ani, and the tendinous arch of the levator ani is penetrated at the lateral side to achieve rendezvous between the 2 approaches. The levator ani is then dissected circumferentially, with identification of the internal pudendal vessels passing through the levator ani at the 4 o'clock and 8 o'clock positions, known as Alcock's canal. The anterior wall of Alcock's canal is formed by the coccygeus muscle and sacrospinous ligament, which are dissected by the transperineal approach to open Alcock's canal, thus obtaining a clear view of the internal pudendal vessels. On the anterior side, the urethra is divided with a laparoscopic linear stapler via the transperineal approach. PRELIMINARY RESULTS: Eight patients with rectal cancer underwent this procedure. The median (range) blood loss was 200 (120-1520) mL and operating time was 467 (321-833) minutes. Reoperation was performed in 1 internal hernia case; however, there were no mortalities, and there were no cases with severe complications or conversion to open surgery. CONCLUSIONS AND FUTURE DIRECTIONS: When performing total pelvic exenteration, transanal minimally invasive surgery offers direct visualization behind the tumor from the anal side and shows the deep pelvic structures, including the retroperitoneal space of the pelvic sidewall.

[Educational Project of Self-Removal of the Intravenous Central Venous Access Port Guided by Patients with Advanced Colorectal Cancer Instructed by a Nurse in the University Hospital].

BACKGROUND: Fluorouracil infusion for 46±5h from the central venous(CV)port is required for mFOLFOX6, FOLFIRI, and FOLFOXIRI in patients with advanced colorectal cancer(CRC), followed by self-removal of the needle by patients. At our hospital, outpatients were instructed for self-removal of the needle, but the results were unsatisfactory. Therefore, instructions for self-removal of the needle from the CV port have been initiated at the patient ward since April 2019, making use of a hospital stay of 3 days. PATIENTS: We retrospectively enrolled patients with chemotherapy-introduced advanced CRC from the CV port who received instructions for self-removal of the needle in the outpatient department and ward between January 2018 and December 2021. RESULTS: Of all patients with advanced CRC, 21 received instructions at the outpatient department(OP)while 67 at patient ward(PW). Incidences of successful self-removal of the needle without the aid of others were similar: 47% in OP and 52% in PW(p=0.80). However, after several additional instructions involving their families, it was higher in PW than in OP(97.0 vs 76.1%, p=0.005). Incidences of successful self-removal of the needle without the aid of others in those aged≥75/<75, and≥65/<65 years were 0%/61.1%, and 35.4%/67.5%, respectively. OP was as a risk factor for failed self-removal of the needle in the logistic regression analysis(odds ratio: 11.19, 95%CI: 1.86- 67.30). CONCLUSION: Repeated instructions involving patients' families during the hospital stay improved the incidence of successful self-removal of the needle. Involvement of patients' families from the beginning may effectively improve self- removal of the needle, particularly in the elderly patients with advanced CRC.

Blood Perfusion Assessment by Indocyanine Green Fluorescence Imaging for Minimally Invasive Rectal Cancer Surgery (EssentiAL trial): A Randomized Clinical Trial.

OBJECTIVE: The aim of the present randomized controlled trial was to evaluate the superiority of indocyanine green fluorescence imaging (ICG-FI) in reducing the rate of anastomotic leakage in minimally invasive rectal cancer surgery. BACKGROUND: The role of ICG-FI in anastomotic leakage in minimally invasive rectal cancer surgery is controversial according to the published literature. METHODS: This randomized, open-label, phase 3, trial was performed at 41 hospitals in Japan. Patients with clinically stage 0-III rectal carcinoma less than 12 cm from the anal verge, scheduled for minimally invasive sphincter-preserving surgery were preoperatively randomly assigned to receive a blood flow evaluation by ICG-FI (ICG+ group) or no blood flow evaluation by ICG-FI (ICG- group). The primary endpoint was the anastomotic leakage rate (grade A+B+C, expected reduction rate of 6%) analyzed in the modified intention-to-treat population. RESULTS: Between December 2018 and February 2021, a total of 850 patients were enrolled and randomized. After the exclusion of 11 patients, 839 were subject to the modified intention-to-treat population (422 in the ICG+ group and 417 in the ICG- group). The rate of anastomotic leakage (grade A+B+C) was significantly lower in the ICG+ group (7.6%) than in the ICG- group (11.8%) (relative risk, 0.645; 95% confidence interval 0.422-0.987; P =0.041). The rate of anastomotic leakage (grade B+C) was 4.7% in the ICG+ group and 8.2% in the ICG- group ( P =0.044), and the respective reoperation rates were 0.5% and 2.4% ( P =0.021). CONCLUSIONS: Although the actual reduction rate of anastomotic leakage in the ICG+ group was lower than the expected reduction rate and ICG-FI was not superior to white light, ICG-FI significantly reduced the anastomotic leakage rate by 4.2%.

Risk factors for the postoperative recurrence of ulcerative colitis-associated colorectal cancer.

PURPOSE: Although ulcerative colitis-associated colorectal cancer (UC-CRC) has been described, there are few reports regarding recurrent cases of UC-CRC. In this study, we investigated the risk factors for UC-CRC recurrence. METHODS: Recurrence-free survival (RFS) was determined for 144 stage I to III cancer patients among 210 UC-CRC patients from August 2002 to August 2019. The Kaplan‒Meier method was used to obtain the cumulative RFS rate, and the Cox proportional hazard model was used to extract recurrence risk factors. The interaction term between cancer stage and prognostic factors specific to UC-CRC was evaluated using the Cox model. The Kaplan‒Meier method was applied by cancer stage to the UC-CRC-specific prognostic factors for which interaction effects were indicated. RESULTS: There were 18 cases of recurrence involving patients with stage I to III cancer, and the recurrence rate was 12.5%. The cumulative 5-year RFS rate was 87.5%. Multivariable analysis showed that age at surgery (hazard ratio (HR): 0.95, 95% CI: 0.91-0.99, p = 0.02), undifferentiated carcinoma (HR: 4.42, 95% CI: 1.13-17.24, p = 0.03), lymph node metastasis (HR: 4.11, 95% CI: 1.08-15.69, p = 0.03), and vascular invasion (HR: 8.01, 95% CI: 1.54-41.65, p = 0.01) were significant risk factors for recurrence. Patients with stage III CRC in the young adult (age < 50 years) group had a significantly worse prognosis than those in the adult (age ≥ 50 years) group (p < 0.01). CONCLUSION: Age at surgery was identified as a risk factor for UC-CRC recurrence. Young adult patients with stage III cancer may have a poor prognosis.

Erratum forTotal Neoadjuvant Chemotherapy in Rectal Cancer: Current Facts and Future Strategies.

[This corrects the article DOI: 10.23922/jarc.2022-060.].

Total Neoadjuvant Chemotherapy in Rectal Cancer: Current Facts and Future Strategies.

Despite preoperative chemoradiotherapy (CRT) and total mesorectal excision improving the local control for locally advanced rectal cancer (LARC), oncologic outcomes and survival were not significantly improved because the main prognostic factor is distant metastasis. Thus, total neoadjuvant chemotherapy (TNT) as a novel approach has been proposed to improve chemotolerance. Since the first randomized phase II trial of TNT versus standard CRT demonstrated in 2012, many prospective and retrospective studies have been published. The initial consensus from TNT studies was that pathological complete response, pathological response of the main tumor, and local control are more favorable at TNT than at CRT. Furthermore, recent studies such as the PAPIDO trial and PRODIGE 23 trial made a major breakthrough of the treatment of TNT, showing that TNT improves the disease-free survival compared to standard treatment with long-course CRT. In addition, several innovative findings of TNT were clarified by prospective phase II trial. In this review, we summarize the most recent advances in TNT based on the findings of pivotal clinical trials for patients with LARC.

Usefulness of delivery catheter on accurate right ventricular septal pacing: Mt FUJI trial.

AIMS: Although the delivery catheter system for pacemaker-lead implantation is a new alternative to the stylet system, no randomized controlled trial has addressed the difference in right ventricular (RV) lead placement accuracy to the septum between the stylet and the delivery catheter systems. This multicentre prospective randomized controlled trial aimed to prove the efficacy of the delivery catheter system for accurate delivery of RV lead to the septum. METHODS AND RESULTS: In this trial, 70 patients (mean age 78 ± 11 years; 30 men) with pacemaker indications of atrioventricular block were randomized to the delivery catheter or the stylet groups. Right ventricular lead tip positions were assessed using cardiac computed tomography within 4 weeks of pacemaker implantation. Lead tip positions were classified into RV septum, anterior/posterior edge of the RV septal wall, and RV free wall. The primary endpoint was the success rate of RV lead tip placement to the RV septum. RESULTS: Right ventricular leads were implanted as per allocation in all patients. The delivery catheter group had higher success rate of RV lead deployment to the septum (78 vs. 50%; P = 0.024) and narrower paced QRS width (130 ± 19 vs. 142 ± 15 ms P = 0.004) than those in the stylet group. However, there was no significant difference in procedure time [91 (IQR 68-119) vs. 85 (59-118) min; P = 0.488] or the incidence of RV lead dislodgment (0 vs. 3%; P = 0.486). CONCLUSION: The delivery catheter system can achieve a higher success rate of RV lead placement to the RV septum and narrower paced QRS width than the stylet system. TRIAL REGISTRATION NUMBER: jRCTs042200014 (https://jrct.niph.go.jp/en-latest-detail/jRCTs042200014).

Rapid processing of threatening faces in the amygdala of nonhuman primates: subcortical inputs and dual roles.

A subcortical pathway through the superior colliculus and pulvinar has been proposed to provide the amygdala with rapid but coarse visual information about emotional faces. However, evidence for short-latency, facial expression-discriminating responses from individual amygdala neurons is lacking; even if such a response exists, how it might contribute to stimulus detection is unclear. Also, no definitive anatomical evidence is available for the assumed pathway. Here we showed that ensemble responses of amygdala neurons in monkeys carried robust information about open-mouthed, presumably threatening, faces within 50 ms after stimulus onset. This short-latency signal was not found in the visual cortex, suggesting a subcortical origin. Temporal analysis revealed that the early response contained excitatory and suppressive components. The excitatory component may be useful for sending rapid signals downstream, while the sharpening of the rising phase of later-arriving inputs (presumably from the cortex) by the suppressive component might improve the processing of facial expressions over time. Injection of a retrograde trans-synaptic tracer into the amygdala revealed presumed monosynaptic labeling in the pulvinar and disynaptic labeling in the superior colliculus, including the retinorecipient layers. We suggest that the early amygdala responses originating from the colliculo-pulvino-amygdalar pathway play dual roles in threat detection.

Being Elderly Is Associated with Infectious and Fatal Postoperative Complications in Ulcerative Colitis Patients.

INTRODUCTION: It is well known that the infectious complications and mortality rates are increased among elderly individuals with ulcerative colitis (UC) during medical treatment. However, there have been few reports on surgery in elderly individuals with UC, and some cohort studies have reported surgical complication and mortality rates similar to those in nonelderly individuals. METHODS: UC patients who underwent colectomy at the Hyogo College of Medicine between April 2012 and March 2020 were included in this study. The patients were classified as elderly (≥65) or nonelderly (<65). Characteristics and postoperative complications were analyzed and compared between the groups; possible risk factors for infectious and fatal complications were also analyzed. RESULTS: In all, 136/599 (22.7%) elderly patients were included. The incidence of infectious and fatal complications was 177/599 (29.5%) and 18/599 (3%), respectively. These complication rates were significantly higher in the elderly than the nonelderly group (p < 0.01). Age ≥65 years at surgery (OR = 2.92, 95% CI: 1.87-4.57, p < 0.01) was identified as an independent risk factor for infectious complications. Age ≥65 years at surgery (OR = 8.03, 95% CI: 2.16-29.83, p < 0.01), American Society of Anesthesiologists score ≥3 (OR = 6.00, 95% CI: 1.40-25.6 p = 0.02), and urgent/emergent surgery (OR = 16.24, 95% CI: 1.70-154.95, p = 0.02) were identified as independent risk factors for fatal complications. DISCUSSION/CONCLUSION: Age ≥65 years was identified as a risk factor for infectious and fatal complications. It is important to avoid urgent/emergent surgery in elderly patients with an ASA score >3 by emphasizing surgical and medical collaboration and optimizing the timing of surgery.

Primordial Capsid and Spooled ssDNA Genome Structures Unravel Ancestral Events of Eukaryotic Viruses.

Marine algae viruses are important for controlling microorganism communities in the marine ecosystem and played fundamental roles during the early events of viral evolution. Here, we have focused on one major group of marine algae viruses, the single-stranded DNA (ssDNA) viruses from the Bacilladnaviridae family. We present the capsid structure of the bacilladnavirus Chaetoceros tenuissimus DNA virus type II (CtenDNAV-II), determined at 2.4-Å resolution. A structure-based phylogenetic analysis supported the previous theory that bacilladnaviruses have acquired their capsid protein via horizontal gene transfer from a ssRNA virus. The capsid protein contains the widespread virus jelly-roll fold but has additional unique features; a third ß-sheet and a long C-terminal tail. Furthermore, a low-resolution reconstruction of the CtenDNAV-II genome revealed a partially spooled structure, an arrangement previously only described for dsRNA and dsDNA viruses. Together, these results exemplify the importance of genetic recombination for the emergence and evolution of ssDNA viruses and provide important insights into the underlying mechanisms that dictate genome organization. IMPORTANCE Single-stranded DNA (ssDNA) viruses are an extremely widespread group of viruses that infect diverse hosts from all three domains of life, consequently having great economic, medical, and ecological importance. In particular, bacilladnaviruses are highly abundant in marine sediments and greatly influence the dynamic appearance and disappearance of certain algae species. Despite the importance of ssDNA viruses and the last couple of years' advancements in cryo-electron microscopy, structural information on the genomes of ssDNA viruses remains limited. This paper describes two important achievements: (i) the first atomic structure of a bacilladnavirus capsid, which revealed that the capsid protein gene presumably was acquired from a ssRNA virus in early evolutionary events; and (ii) the structural organization of a ssDNA genome, which retains a spooled arrangement that previously only been observed for double-stranded viruses.

Weekly Observations of Estuarine Microbial Assemblages during Summer in the Inner Part of Ariake Bay, Japan; Microbial Water-sediment Coupling in Turbid Shallow Waters.

Estuarine microbial assemblages are altered by a number of environmental factors, and knowledge of these changes is essential for understanding the functions of microbes in estuarine ecosystems. The aims of the present study were to examine the relationship between microbial assemblages in the water column and sediment surface, and to identify the environmental factors that influence the short-term dynamics of microbial assemblages in these two zones in summer in the inner part of Ariake Bay. The microbial assemblage of each sample consisted of a mean of 71.1% operational taxonomic units (OTUs), which commonly occurred in the water column and sediment surface, although their relative composition markedly differed between the two zones. In the water column, spatiotemporal changes in microbial assemblages correlated with several environmental factors, such as the nitrogen content in suspended particles, turbidity, and salinity. On the other hand, temporal changes in the sediment's microbial assemblages were governed by a single environmental factor, namely, the oxygen reduction potential. These results suggest that the composition of microbial assemblages in the water column and sediment surface differed even in highly turbid brackish waters with high sediment resuspension, and the environmental factors contributing to the change in the assemblage composition also differed between the water column and sediment.