LLPS of SQSTM1/p62 and NBR1 as outcomes of lysosomal stress response limits cancer cell metastasis.

Liquid droplet has emerged as a flexible intracellular compartment that modulates various cellular processes. Here, we uncover an antimetastatic mechanism governed by the liquid droplets formed through liquid-liquid phase separation (LLPS) of SQSTM1/p62 and neighbor of BRCA1 gene 1 (NBR1). Some of the tyrosine kinase inhibitors (TKIs) initiated lysosomal stress response that promotes the LLPS of p62 and NBR1, resulting in the spreading of p62/NBR1 liquid droplets. Interestingly, in the p62/NBR1 liquid droplet, degradation of RAS-related C3 botulinum toxin substrate 1 was accelerated by cellular inhibitor of apoptosis protein 1, which limits cancer cell motility. Moreover, the antimetastatic activity of the TKIs was completely overridden in p62/NBR1 double knockout cells both in vitro and in vivo. Thus, our results demonstrate a function of the p62/NBR1 liquid droplet as a critical determinant of cancer cell behavior, which may provide insight into both the clinical and biological significance of LLPS.

Reactive sulfur species disaggregate the SQSTM1/p62-based aggresome-like induced structures via the HSP70 induction and prevent parthanatos.

Reactive sulfur species (RSS) have emerged as key regulators of protein quality control. However, the mechanisms by which RSS contribute to cellular processes are not fully understood. In this study, we identified a novel function of RSS in preventing parthanatos, a nonapoptotic form of cell death that is induced by poly (ADP-ribose) polymerase-1 and mediated by the aggresome-like induced structures (ALIS) composed of SQSTM1/p62. We found that sodium tetrasulfide (Na2S4), a donor of RSS, strongly suppressed oxidative stress-dependent ALIS formation and subsequent parthanatos. On the other hand, the inhibitors of the RSS-producing enzymes, such as 3-mercaptopyruvate sulfurtransferase and cystathionine γ-lyase, clearly enhanced ALIS formation and parthanatos. Interestingly, we found that Na2S4 activated heat shock factor 1 by promoting its dissociation from heat shock protein 90, leading to accelerated transcription of HSP70. Considering that the genetic deletion of HSP70 allowed the enhanced ALIS formation, these findings suggest that RSS prevent parthanatos by specifically suppressing ALIS formation through induction of HSP70. Taken together, our results demonstrate a novel mechanism by which RSS prevent cell death, as well as a novel physiological role of RSS in contributing to protein quality control through HSP70 induction, which may lead to better understanding of the bioactivity of RSS.

Computer-assisted image analysis of cytological specimens clarify the correlation between nuclear size and intranuclear cytoplasmic inclusions regardless of BRAFV600E mutation in papillary thyroid carcinoma.

OBJECTIVE: The morphological features of nuclei in cytological and histological specimens were compared and examined for the presence of BRAFV600E mutation and the appearance rate of intranuclear cytoplasmic inclusions (NI). METHODS: BRAFV600E mutation was identified using a mutation-specific antibody (clone; VE1) in 103 thyroid papillary carcinoma cases at Gunma University Hospital. The nuclear area, perimeter, and roundness of the corresponding cytological specimens and haematoxylin and eosin-stained specimens were analysed using image analysis software, and the appearance rate of NI was calculated and compared. RESULTS: BRAFV600E mutation was detected in 71 (69%) cases. The appearance rate of NI was significantly higher in the BRAFV600E mutation-positive group in cytological and histological specimens (P = .0070 and .0184, respectively). Significant differences were observed between the BRAFV600E mutation-negative and -positive groups in the average nuclear area and average nuclear perimeter in cytological specimens (P = .0137 and .0152, respectively). In addition, nuclear enlargement was correlated with the appearance rate of NI regardless of the presence of BRAFV600E mutation in cytological specimens. In the BRAFV600E mutation-negative group, the nuclear area and perimeter were significantly smaller in the lymph node metastasis-positive cases (P = .0182 and .0260, respectively). CONCLUSION: This study found that the appearance rate of NI was positively correlated with the nuclear area and perimeter and negatively correlated with nuclear roundness in cytological specimens. Furthermore, these results were observed regardless of the existence of BRAFV600E mutation. These results have never been previously reported and clearly demonstrate the usefulness of cytological specimens in computer-assisted image analysis.

The E3 Ubiquitin-Protein Ligase RNF4 Promotes TNF-α-Induced Cell Death Triggered by RIPK1.

Receptor-interacting protein kinase 1 (RIPK1) is a key component of the tumor necrosis factor (TNF) receptor signaling complex that regulates both pro- and anti-apoptotic signaling. The reciprocal functions of RIPK1 in TNF signaling are determined by the state of the posttranslational modifications (PTMs) of RIPK1. However, the underlying mechanisms associated with the PTMs of RIPK1 are unclear. In this study, we found that RING finger protein 4 (RNF4), a RING finger E3 ubiquitin ligase, is required for the RIPK1 autophosphorylation and subsequent cell death. It has been reported that RNF4 negatively regulates TNF-α-induced activation of the nuclear factor-κB (NF-κB) through downregulation of transforming growth factor ß-activated kinase 1 (TAK1) activity, indicating the possibility that RNF4-mediated TAK1 suppression results in enhanced sensitivity to cell death. However, interestingly, RNF4 was needed to induce RIPK1-mediated cell death even in the absence of TAK1, suggesting that RNF4 can promote RIPK1-mediated cell death without suppressing the TAK1 activity. Thus, these observations reveal the existence of a novel mechanism whereby RNF4 promotes the autophosphorylation of RIPK1, which provides a novel insight into the molecular basis for the PTMs of RIPK1.

TAK1 Mediates ROS Generation Triggered by the Specific Cephalosporins through Noncanonical Mechanisms.

It is known that a wide variety of antibacterial agents stimulate generation of reactive oxygen species (ROS) in mammalian cells. However, its mechanisms are largely unknown. In this study, we unexpectedly found that transforming growth factor-ß (TGF-ß)-activated kinase 1 (TAK1) is involved in the generation of mitochondrial ROS (mtROS) initiated by cefotaxime (CTX), one of specific antibacterial cephalosporins that can trigger oxidative stress-induced cell death. TAK1-deficient macrophages were found to be sensitive to oxidative stress-induced cell death stimulated by H2O2. Curiously, however, TAK1-deficient macrophages exhibited strong resistance to oxidative stress-induced cell death stimulated by CTX. Microscopic analysis revealed that CTX-induced ROS generation was overridden by knockout or inhibition of TAK1, suggesting that the kinase activity of TAK1 is required for CTX-induced ROS generation. Interestingly, pharmacological blockade of the TAK1 downstream pathways, such as nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, did not affect the CTX-induced ROS generation. In addition, we observed that CTX promotes translocation of TAK1 to mitochondria. Together, these observations suggest that mitochondrial TAK1 mediates the CTX-induced mtROS generation through noncanonical mechanisms. Thus, our data demonstrate a novel and atypical function of TAK1 that mediates mtROS generation triggered by the specific cephalosporins.

Anti-neutrophil Cytoplasmic Antibody-negative Eosinophilic Granulomatosis with Polyangiitis Complicated with Peripheral Neuropathy that Underwent Remission Induction with Mepolizumab Monotherapy.

A 72-year-old woman was admitted to our hospital with numbness in her lower extremities and hypereosinophilia. She was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA). On admission, she was suspected of being complicated with pneumonia and sepsis; therefore, treatment with mepolizumab monotherapy was begun, resulting in partial improvement. After the possibility of a complicating infection was ruled out, corticosteroids were initiated, followed by intravenous gamma globulin therapy. Although the induction of remission of EGPA with mepolizumab monotherapy is not usually recommended, induction with mepolizumab monotherapy may be an option in terms of safety and clinical efficacy in some cases.

Investigating the association between glycaemic traits and colorectal cancer in the Japanese population using Mendelian randomisation.

Observational studies suggest that abnormal glucose metabolism and insulin resistance contribute to colorectal cancer; however, the causal association remains unknown, particularly in Asian populations. A two-sample Mendelian randomisation analysis was performed to determine the causal association between genetic variants associated with elevated fasting glucose, haemoglobin A1c (HbA1c), and fasting C-peptide and colorectal cancer risk. In the single nucleotide polymorphism (SNP)-exposure analysis, we meta-analysed study-level genome-wide associations of fasting glucose (~ 17,289 individuals), HbA1c (~ 52,802 individuals), and fasting C-peptide (1,666 individuals) levels from the Japanese Consortium of Genetic Epidemiology studies. The odds ratios of colorectal cancer were 1.01 (95% confidence interval [CI], 0.99-1.04, P = 0.34) for fasting glucose (per 1 mg/dL increment), 1.02 (95% CI, 0.60-1.73, P = 0.95) for HbA1c (per 1% increment), and 1.47 (95% CI, 0.97-2.24, P = 0.06) for fasting C-peptide (per 1 log increment). Sensitivity analyses, including Mendelian randomisation-Egger and weighted-median approaches, revealed no significant association between glycaemic characteristics and colorectal cancer (P > 0.20). In this study, genetically predicted glycaemic characteristics were not significantly related to colorectal cancer risk. The potential association between insulin resistance and colorectal cancer should be validated in further studies.

Home visiting support for people with hikikomori (social withdrawal) provided by experienced and effective workers.

OBJECTIVES: Hikikomori - an almost complete withdrawal from social interaction first seen in Japan - is becoming an emerging psychological syndrome worldwide. The mental health community in Japan has focused on hikikomori since the 1990s. Hikikomori was initially considered a culture-bound trait, unique to Japan; however, it has become an international concern, and cases have been reported even outside of Japan. While home visiting support for people with hikikomori has gained popularity, an effective solution remains elusive. This paper describes the process involved in effective home visiting support provided by experienced workers to help people with hikikomori. METHOD: Semi-structured interviews were conducted with 21 home-visiting support workers in Japan. Collected data were analysed using a constant comparative method based on Grounded Theory. RESULTS: 'Supporting them in finding their own way to participate in society' was identified as the core category. This core category was substantiated by following three interrelated stages: preparing the involved surroundings for reaching out to a person, maintaining constant communication and expanding the range of activities and relationships. The process encouraged people with hikikomori to enhance their social connections and improved their motivation for social participation. People with hikikomori experiencing despair and isolation began to find pleasure in social participation through the three stages of support provided by home-visiting workers. CONCLUSION: Our study suggests that Home visiting support for people with hikikomori can be enhanced by these three interrelated methods which can help individuals integrate into society and connect with others.

Blood Lipids and the Risk of Colorectal Cancer: Mendelian Randomization Analyses in the Japanese Consortium of Genetic Epidemiology Studies.

The associations between blood lipids, including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides, and low-density lipoprotein cholesterol (LDL-C), and colorectal cancer risk are controversial. We evaluated potential causal relationships between blood lipids and colorectal cancer risk. Using the baseline data from the Japanese Consortium of Genetic Epidemiology studies, we estimated the single-nucleotide polymorphism (SNP)-exposure associations (n = 34,546 for TC, n = 50,290 for HDL-C, n = 51,307 for triglycerides, and n = 30,305 for LDL-C). We also estimated the SNP-outcome associations in another Japanese dataset (n = 7,936 colorectal cancer cases and n = 38,042 controls). We conducted Mendelian randomization (MR) analyses for the association between each blood lipid type and the risk of colorectal cancer using an inverse variance-weighted method. The total variances explained by the selected SNPs in TC (68 SNPs), HDL-C (50 SNPs), log-transformed triglycerides (26 SNPs), and LDL-C (35 SNPs) were 7.0%, 10.0%, 6.2%, and 5.7%, respectively. The odds ratios for colorectal cancer were 1.15 [95% confidence interval (CI), 1.01-1.32] per 1 standard deviation (SD; 33.3 mg/dL) increase in TC, 1.11 (95% CI, 0.98-1.26) per 1 SD (15.4 mg/dL) increase in HDL-C, 1.06 (95% CI, 0.90-1.26) per 1 SD (0.5 log-mg/dL) increase in log-transformed triglycerides, and 1.17 (95% CI, 0.91-1.50) per 1 SD (29.6 mg/dL) increase in LDL-C. Sensitivity analyses consistently suggested the positive association between TC and colorectal cancer, whereas results of each lipid component were inconsistent. In conclusion, this large MR study of a Japanese population showed a potentially causal association between high TC and colorectal cancer risk, although the association between each lipid component and colorectal cancer remained inconclusive. PREVENTION RELEVANCE: In this large MR analysis of a Japanese population, a positive association was found between genetically predicted high total cholesterol (TC) levels and an increased risk of colorectal cancer. Therefore, lowering TC levels by lifestyle modifications or medications may be justified for the purpose of preventing colorectal cancer.

Comparison of sustained hemodiafiltration with continuous venovenous hemodiafiltration for the treatment of critically ill patients with acute kidney injury.

Despite improvements in medical care, the mortality of critically ill patients with acute kidney injury (AKI) who require renal replacement therapy (RRT) remains high. We describe a new approach, sustained hemodiafiltration, to treat patients who suffered from acute kidney injury and were admitted to intensive care units (ICUs). In our study, 60 critically ill patients with AKI who required RRT were treated with either continuous venovenous hemodiafiltration (CVVHDF) or sustained hemodiafiltration (S-HDF). The former was performed by administering a postfilter replacement fluid at an effluent rate of 35 mL/kg/h, and the latter was performed by administering a postfilter replacement fluid at a dialysate-flow rate of 300-500 mL/min. The S-HDF was delivered on a daily basis. The baseline characteristics of the patients in the two treatment groups were similar. The primary study outcome--survival until discharge from the ICU or survival for 30 days, whichever was earlier--did not significantly differ between the two groups: 70% after CVVHDF and 87% after S-HDF. The hospital-survival rate after CVVHDF was 63% and that after S-HDF was 83% (P < 0.05). The number of patients who showed renal recovery at the time of discharge from the ICU and the hospital and the duration of the ICU stay significantly differed between the two treatments (P < 0.05). Although there was no significant difference between the mean number of treatments performed per patient, the mean duration of daily treatment in the S-HDF group was 6.5 +/- 1.0 h, which was significantly shorter. Although the total convective volumes--the sum of the replacement-fluid and fluid-removal volumes--did not differ significantly, the dialysate-flow rate was higher in the S-HDF group. Our results suggest that in comparison with conventional continuous RRT, including high-dose CVVHDF, more intensive renal support in the form of postdilution S-HDF will decrease the mortality and accelerate renal recovery in critically ill patients with AKI.

Redox cycling of 9,10-phenanthrenequinone activates epidermal growth factor receptor signaling through S-oxidation of protein tyrosine phosphatase 1B.

[Page 358, Figure 5C] The label of Western blot data in Figure 5C in the paper was erroneously placed.

Redox cycling of 9,10-phenanthrenequinone activates epidermal growth factor receptor signaling through S-oxidation of protein tyrosine phosphatase 1B.

9,10-Phenanthrenequinone (9,10-PQ) is a polycyclic aromatic hydrocarbon quinone contaminated in diesel exhaust particles and particulate matter 2.5. It is an efficient electron acceptor that induces redox cycling with electron donors, resulting in excessive reactive oxygen species and oxidized protein production in cells. The current study examined whether 9,10-PQ could activate epidermal growth factor receptor (EGFR) signaling in A431 cells through S-oxidation of its negative regulators such as protein tyrosine phosphatase (PTP) 1B. 9,10-PQ oxidized recombinant human PTP1B at Cys215 and inhibited its catalytic activity, an effect that was blocked by catalase (CAT), whereas cis-9,10-dihydroxy-9,10-dihydrophenanthrene (DDP), which lacks redox cycling activity, had no effect on PTP1B activity. Exposure of A431 cells to 9,10-PQ, but not DDP, activated signaling through EGFR and its downstream extracellular signal-regulated kinase 1/2 (ERK1/2), coupled with a decrease of cellular PTP activity. Immunoprecipitation and UPLC-MSE revealed that PTP1B easily undergoes oxidation during exposure of A431 cells to 9,10-PQ. Pretreatment with polyethylene glycol conjugated with CAT (PEG-CAT) abolished 9,10-PQ-generated H2O2 production and significantly blocked the activation of EGFR-ERK1/2 signaling by 9,10-PQ, indicating the involvement of H2O2 in the activation because scavenging agents for hydroxyl radicals had no effect on the redox signal activation. These results suggest that such an air pollutant producing H2O2, activates EGFR-ERK1/2 signaling, presumably through the S-oxidation of PTPs such as PTP1B, and activation of the signal cascade may contribute, at least in part, to cellular responses in A431 cells.

Cryo-EM Structures of Centromeric Tri-nucleosomes Containing a Central CENP-A Nucleosome.

The histone H3 variant CENP-A is a crucial epigenetic marker for centromere specification. CENP-A forms a characteristic nucleosome and dictates the higher-order configuration of centromeric chromatin. However, little is known about how the CENP-A nucleosome affects the architecture of centromeric chromatin. In this study, we reconstituted tri-nucleosomes mimicking a centromeric nucleosome arrangement containing the CENP-A nucleosome, and determined their 3D structures by cryoelectron microscopy. The H3-CENP-A-H3 tri-nucleosomes adopt an untwisted architecture, with an outward-facing linker DNA path between nucleosomes. This is distinct from the H3-H3-H3 tri-nucleosome architecture, with an inward-facing DNA path. Intriguingly, the untwisted architecture may allow the CENP-A nucleosome to be exposed to the solvent in the condensed chromatin model. These results provide a structural basis for understanding the 3D configuration of CENP-A-containing chromatin, and may explain how centromeric proteins can specifically target the CENP-A nucleosomes buried in robust amounts of H3 nucleosomes in centromeres.

Nuclear-accumulated SQSTM1/p62-based ALIS act as microdomains sensing cellular stresses and triggering oxidative stress-induced parthanatos.

Aggresome-like induced structures (ALIS) have been described as ubiquitinated protein-containing aggresomes transiently formed in response to various stresses. In this study, we provide evidence that ALIS composed of SQSTM1/p62 act as a key determinant of oxidative stress-induced parthanatos, which is newly discovered and distinct from regular programmed cell death. Interestingly, we first found that chemical stresses induced by particular chemical drugs, such as several cephalosporin antibiotics, cause oxidative stress-mediated parthanatos, accompanied by the ALIS formation. Blocking the ALIS formation potently suppressed the parthanatos, and p62 knockout cells exhibited the attenuated ALIS formation and high resistance to parthanatos. Moreover, we also found that the redox-sensing activity of p62 is required for nuclear accumulation of the p62-based ALIS, resulting in the induction of parthanatos. Together, our results demonstrate unexpected functions of p62 and ALIS as cell death mediators sensing oxidative stress, and thus uncover a novel mechanism whereby p62 mediates parthanatos.

[Sectional acrylic dentures for a partially edentulous patient with microstomia: a clinical report].

PATIENT: The patient was a 48-year-old partially edentulous male with microstomia. His chief complaints were masticatory disturbance and aesthetic problems caused by missing teeth. After trayless impressions for diagnostic casts were made, sectional trays and a sectional record block were used for the definitive impression and maxillomandibular registration. Maxillary and mandibular acrylic sectional dentures were simultaneously delivered. DISCUSSION: Low caries activity, minimal occlusal force, appropriate plaque control, and simple designs for connecting portions of the two halves of the sectional dentures might lead to satisfactory results in this case. CONCLUSION: No problems have been observed for approximately 6 years after delivery of the acrylic sectional dentures for this microstomic patient.

Regulation of B cell differentiation by the ubiquitin-binding protein TAX1BP1.

Tax1-binding protein 1 (TAX1BP1) is a ubiquitin-binding protein that restricts nuclear factor-κB (NF-κB) activation and facilitates the termination of aberrant inflammation. However, its roles in B-cell activation and differentiation are poorly understood. To evaluate the function of TAX1BP1 in B cells, we established TAX1BP1-deficient DT40 B cells that are hyper-responsive to CD40-induced extracellular signal-regulated kinase (ERK) activation signaling, exhibit prolonged and exaggerated ERK phosphorylation and show enhanced B lymphocyte-induced maturation protein 1 (Blimp-1; a transcription factor inducing plasma cell differentiation) expression that is ERK-dependent. Furthermore, TAX1BP1-deficient cells exhibit significantly decreased surface IgM expression and increased IgM secretion. Moreover, TAX1BP1-deficient mice display reduced germinal center formation and antigen-specific antibody production. These findings show that TAX1BP1 restricts ERK activation and Blimp-1 expression and regulates germinal center formation.

Thrombomodulin in the management of acute cholangitis-induced disseminated intravascular coagulation.

AIM: To evaluate the need for thrombomodulin (rTM) therapy for disseminated intravascular coagulation (DIC) in patients with acute cholangitis (AC)-induced DIC. METHODS: Sixty-six patients who were diagnosed with AC-induced DIC and who were treated at our hospital were enrolled in this study. The diagnoses of AC and DIC were made based on the 2013 Tokyo Guidelines and the DIC diagnostic criteria as defined by the Japanese Association for Acute Medicine, respectively. Thirty consecutive patients who were treated with rTM between April 2010 and September 2013 (rTM group) were compared to 36 patients who were treated without rTM (before the introduction of rTM therapy at our hospital) between January 2005 and January 2010 (control group). The two groups were compared in terms of patient characteristics at the time of DIC diagnosis (including age, sex, primary disease, severity of cholangitis, DIC score, biliary drainage, and anti-DIC drugs), the DIC resolution rate, DIC score, the systemic inflammatory response syndrome (SIRS) score, hematological values, and outcomes. Using logistic regression analysis based on multivariate analyses, we also examined factors that contributed to persistent DIC. RESULTS: There were no differences between the rTM group and the control group in terms of the patients' backgrounds other than administration. DIC resolution rates on day 9 were higher in the rTM group than in the control group (83.3% vs 52.8%, P < 0.01). The mean DIC scores on day 7 were lower in the rTM group than in the control group (2.1 ± 2.1 vs 3.5 ± 2.3, P = 0.02). The mean SIRS scores on day 3 were significantly lower in the rTM group than in the control group (1.1 ± 1.1 vs 1.8 ± 1.1, P = 0.03). Mortality on day 28 was 13.3% in the rTM group and 27.8% in the control group; these rates were not significantly different (P = 0.26). Multivariate analysis identified only the absence of biliary drainage as significantly associated with persistent DIC (P < 0.01, OR = 12, 95%CI: 2.3-60). Although the difference did not reach statistical significance, primary diseases (malignancies) (P = 0.055, OR = 3.9, 95%CI: 0.97-16) and the non-use of rTM had a tendency to be associated with persistent DIC (P = 0.08, OR = 4.3, 95%CI: 0.84-22). CONCLUSION: The add-on effects of rTM are anticipated in the treatment of AC-induced DIC, although biliary drainage for AC remains crucial.

Hemostasis Achieved Endoscopically for Diverticular Bleeding from the Horizontal Portion of the Duodenum.

Diverticulum of the horizontal portion of the duodenum is a rare cause of upper gastrointestinal (GI) bleeding. Since it is difficult to access the horizontal portion of the duodenum by standard upper GI endoscopy, only a very few cases of endoscopic hemostasis have been reported. Herein, we report a case of diverticular bleeding from the horizontal portion of the duodenum for which hemostasis was achieved using a small-caliber colonoscope, which has an insertion part designed with a passive-bending function/high-force transmission and a transparent tip hood.

Urgent computed tomography for determining the optimal timing of colonoscopy in patients with acute lower gastrointestinal bleeding.

OBJECTIVE: We evaluated the diagnostic performance of computed tomography (CT) as an initial radiologic test for assessing the optimal timing of colonoscopy in patients with acute lower gastrointestinal bleeding (LGIB) and investigated the effectiveness of contrast-enhanced (CE) CT for detecting colonic diverticular bleeding. METHODS: This was a retrospective study of 1,604 consecutive patients who visited or were referred to St. Marianna University Hospital due to acute LGIB and underwent colonoscopy within three months after presentation between September 2004 and December 2012. The clinicopathological data of the subjects were obtained from their medical records. RESULTS: Among the 1,604 patients presenting with LGIB, 879 (55%) underwent a CT scan. Elective colonoscopy was considered in cases in which typical colonic wall thickening was observed on CT, suggesting colonic inflammation or malignancy (239 patients; 27%). The diagnoses in the elective cases included ischemic colitis (38%), infectious colitis (8%), inflammatory bowel disease (8%) and malignancy (5%). Urgent colonoscopy was performed after the CT examination in 640 cases (73%). The most common presumptive CT diagnosis was diverticulum (402/640; 63%). Of the 638 patients who underwent CE-CT, diverticula were observed in 346 cases, including 104 cases of extravasation indicating ongoing diverticular bleeding. Among these 104 patients, the site of bleeding was identified in 71 subjects (68%) during colonoscopy. The rate of detection of the bleeding source on colonoscopy was significantly higher in the patients with extravasation on CE-CT than in those without extravasation on CE-CT (68% vs. 20%, respectively; p<0.001). CONCLUSION: Urgent CT is useful for determining the optimal timing of colonoscopy in cases of acute LGIB. CE-CT may be used to depict the presence and location of active hemorrhage and provides useful information for subsequent colonoscopy, especially in patients with diverticular bleeding.

Five novel and four recurrent point mutations in the antithrombin gene causing venous thrombosis.

We analyzed the antithrombin (AT) gene in 9 unrelated Japanese patients with thrombotic disease. All 7 exons, the splice junctions, and the 5'-flanking region of the AT gene were amplified by polymerase chain reaction and sequenced directly. Nine different point mutations, all in the heterozygous state, were identified. Five novel (M-32T, M89K, L146H, Q159X, and L409P) and 2 previously reported (R132X and R359X) point mutations were identified in patients with type 1 deficiency. Two different missense mutations, R393C and R393H, located in the protease reactive site were detected in patients with type 2 deficiency. No other sequence abnormalities in the AT gene were detected by direct sequencing. None of the mutations was present in 100 alleles from 50 unrelated Japanese control subjects Although type 1 deficiency was diagnosed in patient 7 on the basis of approximately 50% AT antigen and activity levels, the data indicated that the novel L409P mutation is a type 2 pleiotropic effects (PE) deficiency because its location in the C-terminal portion of the reactive site is similar to the locations of reported PE type mutations, and it is highly conserved among other serpins.