Thrombosis from a prothrombin mutation conveying antithrombin resistance.

We identified a novel mechanism of hereditary thrombosis associated with antithrombin resistance, with a substitution of arginine for leucine at position 596 (p.Arg596Leu) in the gene encoding prothrombin (called prothrombin Yukuhashi). The mutant prothrombin had moderately lower activity than wild-type prothrombin in clotting assays, but the formation of thrombin-antithrombin complex was substantially impaired. A thrombin-generation assay revealed that the peak activity of the mutant prothrombin was fairly low, but its inactivation was extremely slow in reconstituted plasma. The Leu596 substitution caused a gain-of-function mutation in the prothrombin gene, resulting in resistance to antithrombin and susceptibility to thrombosis.

Ribavirin-induced intracellular GTP depletion activates transcription elongation in coagulation factor VII gene expression.

Coagulation FVII (Factor VII) is a vitamin K-dependent glycoprotein synthesized in hepatocytes. It was reported previously that FVII gene (F7) expression was up-regulated by ribavirin treatment in hepatitis C virus-infected haemophilia patients; however, its precise mechanism is still unknown. In the present study, we investigated the molecular mechanism of ribavirin-induced up-regulation of F7 expression in HepG2 (human hepatoma cell line). We found that intracellular GTP depletion by ribavirin as well as other IMPDH (inosine-5'-monophosphate dehydrogenase) inhibitors, such as mycophenolic acid and 6-mercaptopurine, up-regulated F7 expression. FVII mRNA transcription was mainly enhanced by accelerated transcription elongation, which was mediated by the P-TEFb (positive-transcription elongation factor b) complex, rather than by promoter activation. Ribavirin unregulated ELL (eleven-nineteen lysine-rich leukaemia) 3 mRNA expression before F7 up-regulation. We observed that ribavirin enhanced ELL3 recruitment to F7, whereas knockdown of ELL3 diminished ribavirin-induced FVII mRNA up-regulation. Ribavirin also enhanced recruitment of CDK9 (cyclin-dependent kinase 9) and AFF4 to F7. These data suggest that ribavirin-induced intracellular GTP depletion recruits a super elongation complex containing P-TEFb, AFF4 and ELL3, to F7, and modulates FVII mRNA transcription elongation. Collectively, we have elucidated a basal mechanism for ribavirin-induced FVII mRNA up-regulation by acceleration of transcription elongation, which may be crucial in understanding its pleiotropic functions in vivo.

Treatment outcomes of radiotherapy for malignant psoas syndrome: A single-center retrospective study.

INTRODUCTION: The efficacy of radiotherapy for symptomatic relief of malignant psoas syndrome (MPS) remains unknown because there are limited publications with high level evidence, including analyses with sufficient number of cases, clinical trials, and systematic reviews about radiotherapy for MPS. We aimed to investigate the characteristics of and symptom relief rates in patients treated with radiotherapy for MPS in palliative intent. METHODS: In this single-center retrospective study, we analyzed data of 22 consecutive patients treated with radiotherapy for MPS at our institution in Japan between 2012 and 2022. We recorded patient characteristics, including primary site, invasion pattern, recognition of MPS by the attending physician, radiation regimen, biological effective dose with α/ß = 10 Gy (BED10), and adverse events. Since no objective evaluation index for palliative radiotherapy for non-bone metastases has been established, we modified and used an International Consensus on Palliative Radiotherapy Endpoint, which was originally used for bone metastases, to evaluate symptom relief in the present retrospective study. "Response" was defined as symptom relief described in medical records or the use of analgesic medications reduced by ≥25% within 3 months post-initiation of radiotherapy. RESULTS: Genitourinary organs (41%) were the most common primary-tumor sites. MPS was caused by metastasis in the iliopsoas muscle in 14 patients (64%) and by direct invasion of the primary tumor in eight patients (36%). Since the optimal radiation dose for MPS has not been established, the radiation dose varied from low dose, which are used in palliative radiotherapy for painful bone metastases, to high dose with conventional fraction using 1.8 to 2 Gy per fraction, with a median BED10 of 48 Gy (range, 10.6-79.2 Gy). Fifteen patients (68%) achieved a response. No acute nor late adverse events of grade 2 or higher, according to Common Terminology Criteria for Adverse Events version 5.0, were reported during the observation period. CONCLUSION: Radiotherapy for symptomatic MPS might be an effective treatment option with a high response rate (68%) and minimal adverse events. Since the present study is a retrospective study with small number of cases, a prospective study with a larger sample size is required.

The nitric oxide-cyclic guanosine monophosphate pathway inhibits the bladder ATP release in response to a physiological or pathological stimulus.

The release of ATP from the epithelium of the urinary bladder (urothelium) in response to mechanical/chemical stimuli contributes to the visceral sensation in the micturition reflex. The nitric oxide (NO)-mediated induction of cyclic guanosine monophosphate (cGMP) has been detected in urothelial cells and may inhibit the micturition reflex. However, the function of the NO-cGMP pathway in the regulation of urothelial ATP release remains poorly understood in contrast to its effects on smooth muscles or primary afferent nerves. Therefore, we investigated the relevance of the NO-cGMP pathway to ATP release on the mucosal side in the present study. The administration of l-arginine (NO precursor) or NOC 12 (NO donor) significantly reduced ATP release to the mucosal side at a physiologically normal urine storage pressure (5 cmH2 O). L-NAME (NO synthase inhibitor) significantly increased the distention-induced release of ATP. The phosphodiesterase-5 inhibitor, sildenafil, which increases cGMP levels, inhibited distention-induced ATP release. Furthermore, sildenafil significantly reduced ATP release in response to the administration of lipopolysaccharide. These results suggest that the NO-cGMP pathway inhibited urothelial ATP release during the storage phase under both physiological and pathological conditions.

The factorial structure of the Mini-Mental State Examination (MMSE) in Japanese dementia patients.

BACKGROUND: The Mini-Mental State Examination (MMSE) is one of the most commonly used instruments in the evaluation of global cognitive status. Few studies have investigated the relationship among its components in terms of factorial structure in Japanese individuals suffering from dementia. The aims of this study were: 1) to analyze the factorial structure of MMSE in Japanese dementia patients, 2) to clarify the MMSE static structure in identifying different cognitive profiles and understanding how these profiles are related to levels of dysfunction in subsets of dementia patients. METHODS: 30,895 consecutive outpatients with dementia were evaluated. The 11 subtests composing the MMSE and the global MMSE score were analyzed. Factor analysis based on principal component analysis with Promax rotation was applied to the data representing the frequency of failures in each subtest as identified by the MMSE. RESULTS: Factor analysis identified three factors that explained approximately 44.57% of the total variance. The first factor, immediate memory, essentially constituted a simple index of the reading and writing subtests. The second factor, orientation and delayed recall, expressed the ability to handle new information. The third factor, working memory, was most closely related to the severity of dementia at the time of test administration. CONCLUSIONS: Japanese dementia patients appear to develop difficulty handling new information in the early stages of their disease. This finding, and our finding that there is a factor associated with disease severity, suggest that understanding the specific factors related to subtest items, which underlie the total MMSE score may be useful to clinicians in planning interventions for Japanese patients in the early stages of dementia.

Outcomes of Definitive Chemoradiotherapy for Stage IVa (T4b vs. N4) Esophageal Squamous Cell Carcinoma Based on the Japanese Classification System: A Retrospective Single-Center Study.

The differences in prognoses or progression patterns between T4b non-N4 and non-T4b N4 esophageal squamous cell carcinoma post chemoradiotherapy (CRT) is unclear. This study compared the outcomes of CRT for stage IVa esophageal squamous cell carcinoma according to T/N factors. We retrospectively identified 66 patients with stage IVa esophageal squamous cell carcinoma who underwent definitive CRT at our center between January 2009 and March 2013. The treatment outcomes, i.e., progression patterns, prognostic factors, and toxicities based on version 5.0 of the National Cancer Institute Common Terminology Criteria for Adverse Events, were studied. The patients (56 men and 10 women) had a median age of 67 (range: 37-87) years. The T/N classifications were T4b non-N4 (28/66), non-T4b N4 (24/66), and T4b N4 (14/66). Objective response was achieved in 57 patients (86.4%, (95% confidence interval, 74.6-94.1%)). There were no significant differences between the T/N groups in terms of overall survival, progression-free survival, and progression pattern. We found no significant differences in prognoses or progression patterns among patients with T4b non-N4, non-T4b N4, and T4b N4 esophageal squamous cell carcinoma. Thus, it seems impractical to modify CRT regimens based on T/N factors.

Effect of the types of pretreatment imaging modalities on the treatment response to palliative radiation for painful bone metastases from solid cancer: a single-center retrospective analysis.

BACKGROUND: Determining the appropriate gross tumor volume is important for irradiation planning in addition to palliative radiation for bone metastases. While irradiation planning is commonly performed using simulation computed tomography (CT), magnetic resonance imaging (MRI), bone scintigraphy, and 18fluorodeoxyglucose-positron emission tomography-CT (18FDG-PET-CT) are more sensitive for detecting bone metastasis and invasion areas. Therefore, this study evaluated whether pretreatment imaging modalities influenced the response to palliative radiation therapy (i.e., the irradiation effect) for painful bone metastases from solid malignant carcinomas. METHODS: Consecutive patients with painful bone metastases treated with palliative radiation between January 2013 and December 2017 at our institution were included. We retrospectively investigated the pretreatment images from the different imaging modalities (CT, MRI, bone scintigraphy, and 18FDG-PET-CT) obtained between 1 month before and the initiation of palliative radiation and determined the primary site of carcinoma, histological type, metastatic lesion type (osteolytic, osteoblastic, or mixed), pathological fracture, and metastatic site (vertebral or not). We then evaluated the relationship between these factors and treatment response. We defined "response" as the condition in which patients achieved pain relief or reduced the use of painkiller medicines. RESULTS: In total, 131 patients (78 men and 53 women) were included; the median age was 66 years (range, 24-89 years). Prescribed doses were 8-50 Gy/1-25 fractions with 2-8 Gy/fraction. Among the 131 patients, 105 were responders (response rate, 80%). The imaging modalities performed before irradiation were CT in 131 patients, MRI in 54, bone scintigraphy in 56, and 18FDG-PET-CT in 14. The Welch t-test and chi-square test showed no significant association between treatment response and each factor. Multiple logistic regression analysis including the imaging modality, metastatic site, and pathological fracture also showed no significant association with each factor. CONCLUSIONS: There was no significant relationship between the type of pretreatment imaging and treatment response for painful bone metastases. Thus, setting the appropriate radiation field according to CT images and clinical findings could help avoiding further image inspection before palliative radiation for painful bone metastases.

Development of a new laboratory test to evaluate antithrombin resistance in plasma.

INTRODUCTION: We recently reported a variant prothrombin (p.Arg596Leu: prothrombin Yukuhashi) that confers antithrombin resistance to patients with hereditary thrombosis. To detect antithrombin resistance in plasma, we devised a laboratory test analyzing the kinetics of thrombin inactivation using antithrombin. MATERIALS AND METHODS: After incubation with prothrombin activator components (phospholipids, CaCl2, and snake venom), samples were treated with excess antithrombin in the presence or absence of heparin for various time periods. Subsequently, H-D-Phe-Pip-Arg-p-nitoranilide was added and changes in absorbance/min (ΔA/min) were measured at 405 nm. RESULTS: After 1 min inactivation using antithrombin and heparin, the relative residual thrombin activity of recombinant mutant prothrombin (34.3% ± 2.2%) was higher than that of the wild-type (6.3% ± 1.2 %). After 30 min without heparin, the relative residual thrombin activity of recombinant mutant prothrombin (95.8% ± 0.4%) was higher than that of the wild-type (10.1% ± 1.7%), indicating that this assay could detect antithrombin resistance of the variant 596Leu prothrombin. Moreover, warfarinized plasmas from 2 heterozygous patients with prothrombin Yukuhashi mutation clearly showed higher values of the relative residual thrombin activity than those from 5 thrombosis patients lacking the mutation in the presence or absence of heparin. CONCLUSIONS: We have devised a laboratory test to detect antithrombin resistance in plasma by analyzing the kinetics of thrombin inactivation using antithrombin. This assay may be useful for detecting antithrombin resistance in plasma, even in warfarinized patients.

Molecular mechanisms of syndecan-4 upregulation by TNF-α in the endothelium-like EAhy926 cells.

Syndecan-4, a cell-surface heparan sulfate proteoglycan, can participate in inflammation and wound healing as a host defense molecule. Tumour necrosis factor (TNF)-α, one of the most potent proinflammatory cytokines, is known to upregulate syndecan-4 expression, but the precise mechanisms are unclear. To elucidate these mechanisms in detail, we examined syndecan-4 upregulation by TNF-α in the endothelium-like EAhy926 cell. Of the two putative nuclear factor kappa-B (NF-κB) binding sites in the syndecan-4 gene (SDC4) promoter, deletion or mutation of one or both sites significantly diminished the effects of TNF-α. Electrophoretic mobility shift assays showed that p65 and c-Rel, but not p50, bound to these NF-κB binding sites, whereas pull-down assays showed binding of all three NF-κB components. Chromatin immunoprecipitation assays clearly showed that p65 and phosphorylated p65, but not p50 or c-Rel, bound to the SDC4 promoter. An NF-κB inhibitor, p65 knockdown and a transcriptional elongation inhibitor completely blocked the effect of TNF-α on SDC4 promoter activity and significantly, but not completely, blocked that on SDC4 mRNA expression. These data suggest that NF-κB p65 could be a key mediator of syndecan-4 upregulation by TNF-α through two binding sites in the SDC4 promoter, but other NF-κB-p65 independent pathways might also be involved through transcriptional elongation.