Left Ventricular Abnormality and Covert Atrial Fibrillation in Embolic Stroke of Undetermined Source

Aims: The relationship between left ventricular (LV) function and AF detection in embolic stroke of undetermined source (ESUS) patients with insertable cardiac monitors (ICMs) remains unclear. We investigated the association between LV function and AF detection in patients with ESUS after ICMs implantation. Methods: We enrolled patients with ESUS who underwent ICMs implantation from September 2016 to September 2020 using a single-center, prospective registry. LV systolic and diastolic functions were assessed on precordial echocardiography by LV fractional shortening (LVFS) and average E/e’, respectively. Associations between characteristics of LV function and detection of AF by ICMs were analyzed. Results: Participants comprised 101 patients (median age, 74 years; male, 62%). During a median follow-up period of 442 days (interquartile range (IQR), 202–770 days), AF was detected in 24 patients (24%). Median duration from ICMs implantation to AF detection was 71 days (IQR, 13–150 days). When LVFS and E/e’ were dichotomized by cutoff value, each of low LVFS (＜35.5%; adjusted hazard ratio (HR), 4.77; 95% confidence interval (CI), 1.77–12.9) and high E/e’ (≥ 8.65; adjusted HR, 4.56; 95%CI, 1.17–17.7) were independently associated with AF detection after adjusting for age and sex. When patients were divided into four groups according to dichotomized LVFS and E/e’, the combination of low LVFS and high E/e’ was independently associated with AF. Conclusions: In patients with ESUS after ICMs implantation, the LV characteristics of low LVFS and high E/e’ were associated with AF detection.     

Treatment of secondary pneumothorax with interstitial lung disease: the surgical indications at the start of treatment is important

BackgroundSecondary pneumothorax with interstitial lung disease (ILD) is often difficult to treat in comparison to primary pneumothorax. The purpose of this study was to analyze the actual management and outcome, and to find the most effective treatment.MethodsAmong 180 patients with pneumothorax caused by ILD, who were managed between January 2000 and April 2021, 129 patients were included. Fifty-one patients with observation only were excluded. In the present study, a patient was considered to be cured if their chest tube could be removed.ResultsThe managements included chest tube drainage alone (n=41), pleurodesis (n=67), bronchoscopic treatment (n=14), and surgery (include overlapping cases) (n=25). The mean number of pleurodesis treatments was 2.4 (range, 1–9), and the most frequently used agent was blood-patch. All patients who received bronchoscopic treatment underwent bronchial occlusion with silicon spigots. The surgical procedures included bullectomy (n=20), lung cyst ligation (n=3), pleural covering with oxidized cellulose sheet (n=1), and spraying of fibrin glue alone (n=1). One hundred patients (77.5%) were curatively treated, 27 patients (20.9%) died, and 2 patients were transferred without chest tube removal. Among 25 patients who received surgery [including 6 patients with performance status (PS) ≥2], 24 patients (96.0%) were cured, and 1 patient died due to an acute exacerbation of ILD after surgery. The univariate analysis revealed that PS ≥2 and >3 pleurodesis treatments were significant non-curative factors, while steroid treatment before the development of pneumothorax was not.ConclusionsThe outcomes of surgery for pneumothorax in patients with ILD were good, and it is desirable to consider the surgical indications.     

Determination of diagnostic threshold in harmonization and comparison of clinical utility for five major antiphospholipid antibody assays used in Japan

BackgroundAnticardiolipin antibodies (aCL) and anti‐β₂‐glycoprotein I antibodies (aβ₂GPI) are essential in diagnosing antiphospholipid syndrome (APS) according to the international APS guideline. Five commercial assays for aCL and aβ₂GPI are available in Japan, but their test results are quite discordant. For harmonization of diagnosing APS, upper reference limit (URL) and diagnostic accuracy of each assay were evaluated and compared by testing common sets of specimens across all assays.MethodsWe evaluated two manual and three automated assays for aCL and aβ₂GPI of IgG‐ and IgM classes. 99%URL (the upper limit of reference interval: as per guideline) together with 97.5%URL were determined by testing sera from 198 to 400 well‐defined healthy subjects. Both URLs were compared with the cutoff values, which were determined based on ROC analysis by testing 50 each of plasma specimens from patients with/without APS. Diagnostic accuracy was evaluated as area under curve (AUC) of the ROC curve.ResultsA variable degree of discrepancy between URLs and the cutoff values was observed, which was partly attributable to between‐year assay variability. 97.5%URLs were set lower and closer to the cutoff values than 99%URLs. For all assays, diagnostic accuracies of both aβ₂GPI‐IgG and aCL‐IgG were generally high (AUC: 0.84−0.93); whereas those for IgM‐class assays were low (AUC: 0.57−0.67), implicating its utility is limited to rare IgG negative APS cases.ConclusionTo ensure harmonized APS diagnosis, the diagnostic thresholds of the five assays were evaluated by common procedures. Contrary to the guideline, 97.5%URL is rather recommended for diagnosing APS, which showed a closer match to the cutoff value.     

Negative regulation of cell motile and invasive activities by lysophosphatidic acid receptor-3 in colon cancer HCT116 cells

Lysophosphatidic acid (LPA) mediates a wide range of biological responses with G protein-coupled transmembrane receptors (LPA receptors). So far, at least six types of LPA receptors (LPA receptor-1 (LPA₁) to LPA₆) have been identified. Recently, it has been reported that LPA₃ indicates opposite effects on cellular functions of cancer cells. In the present study, to assess a biological role of LPA₃ on cell migration ability of colon cancer cells, we generated LPA receptor-3 (LPAR3) knockdown (HCT-sh3-3) cells from HCT116 and measured cell motile and invasion activities. In motility assay with a cell culture insert, HCT-sh3-3 cells showed significantly high cell motile activity, compared with control cells. For invasion assay, the filter was coated with Matrigel. The invasive activity of HCT-sh3-3 cells was significantly higher than that of control cells. Furthermore, we also examined the effects of LPAR3 knockdown on the interaction between colon cancer cells and endothelial F-2 cells. When F-2 cells were cultured with serum-free DMEM containing a supernatant from HCT-sh3-3 cells, the cell growth rate and migration activity of F-2 cells were significantly stimulated, associating with the elevated expressions of vascular endothelial growth factor (VEGF)-A and VEGF-C genes in HCT-sh3-3 cells. These results suggest that LPA₃ may act as a negative regulator on cell motile and invasive abilities of colon cancer HCT116 cells.     

A case of factor X (FX) deficiency due to novel mutation V196M,FX Hofu

The patient, a 20-year-old male, was found to have a slightly prolonged prothrombin time (PT). No episodes of bleeding were noted. The measurement of coagulation factors revealed that the level of factor X (FX) activity was solely deficient, 51% (normal range: 70–130% ), and that of FX antigen was 100%. Analysis of the entire FX gene revealed the novel missense mutation of GTG to ATG, resulting in the substitution of the 196th amino acid valine → methionine. The mother and younger brother had a normal PT time and expressed no episode of bleeding. The mother exhibited a normal level of FX activity and antigen; however the younger brother showed a slight decrease in both the parameters. This mutation was not observed in the mother and younger brother. Polymorphism is not observed at this point in healthy persons. The present novel FX mutation was named FX Hofu.     

Increased macrophage colony-stimulating factor levels in patients with Graves’ disease

Previous studies have found markedly elevated serum concentrations of proinflammatory cytokines in patients with Graves’ disease (GD). We investigated the role of macrophage colony-stimulating factor (M-CSF) in GD. We assayed concentrations of M-CSF in sera from 32 patients with GD (25 untreated; 7 receiving thiamazole therapy). We also studied 32 age-matched healthy subjects as controls. Relationships between serum M-CSF and both thyroid state and serum lipids were examined. Moreover, to examine the effect of thyroid hormone alone on serum M-CSF, T3 was administered orally to normal subjects. Serum concentrations of M-CSF in GD patients who were hyperthyroid were significantly increased compared with GD patients who were euthyroid (P < 0.05) and control subjects (P < 0.0001). Serum M-CSF concentrations correlated closely with T3 levels in patients (r = 0.51, P < 0.005). Serial measurement of five individual patients revealed that serum concentrations of M-CSF were significantly decreased (P < 0.05), reaching normal control values upon attainment of euthyroidism. Furthermore, oral T3 administered to 15 volunteers for 7 days produced significant increases in serum levels of M-CSF (P < 0.05). The close correlation between serum M-CSF and serum thyroid hormone levels suggests that high circulating levels of thyroid hormones may directly or indirectly potentiate the production of M-CSF in patients with GD.     

Chronic hepatitis C associated with anti-liver/kidney microsome-1 antibody is not a subgroup of autoimmune hepatitis

To determine whether “autoimmune hepatitis type IIb” should be categorized as a subgroup of autoimmune hepatitis, we conducted a clinicopathological study of 25 adult Japanese patients who were positive for anti-liver/kidney microsome-1 (anti-LKM-1) antibody and infected with the hepatitis C virus (HCV). Anti-LKM-1 was determined by indirect immunofluo-rescence and by the double immunodiffusion assays we have developed. Twenty-two patients did not present any unusual symptoms or any associated diseases during the course of their chronic HCV infection. The spectrum of HCV genotypes of these patients did not significantly differ from that of anti-LKM-1-negative Japanese patients with chronic hepatitis C. Histological examination of liver biopsy specimens showed the usual characteristics of chronic hepatitis C and lack of characteristics of autoimmune hepatitis type I. No disease-specific HLA haplotypes were noted, and HLA-DR4, which is detectable in 88.7% of Japanese patients with autoimmune hepatitis type I, was detected in only 50.0% of our group, the same rate as the background frequency. Prednisolone was effective in none of the six patients treated, but interferon was effective in six of ten treated patients (60%). From these results, we conclude that “autoimmune hepatitis type IIb” should not be categorized as autoimmune hepatitis, and that this subgroup is essentially chronic hepatitis C in which an autoantibody has been produced during the course of chronic HCV infection.     

An effective strategy to reduce blood pressure after forest walking in middle-aged and aged people

[Purpose] Forest walking may be effective for human health, but little information is available about effects of energy expenditure on blood pressure responses after forest walking. The aim of this study was to investigate the relationship between the activity energy expenditure and changes in blood pressure in individuals after forest walking. [Subjects] The subjects were 54 middle-aged and elderly people. [Methods] All subjects walked in the forest for approximately 90 min. Blood pressure, salivary amylase, and the Profile of Mood States were evaluated before and after forest walking, and activity energy expenditure was monitored throughout forest walking. Subjects were divided into two groups according to mean arterial pressure changes: a responder group (>5% decreases) and a nonresponder group (<5%). [Results] Forest walking significantly reduced the mean arterial pressure and improved the Profile of Mood States in both groups. Activity energy expenditure was related to changes in mean arterial pressure in the responder group, while this relation was not observed in the nonresponder group. Differential activity energy expenditure did not strongly affect improvement of the Profile of Mood States. [Conclusion] Greater walking-related greater activity energy expenditure might be required to accentuate physiological beneficial effects on in middle-aged and aged people. Furthermore, the forest environment per se can attenuate psychological stress.Key words: Hypertension, Profile of Mood States, Responder and nonresponder     

Discovery of Novel SPAK Inhibitors That Block WNK Kinase Signaling to Cation Chloride Transporters

Upon activation by with-no-lysine kinases, STE20/SPS1-related proline–alanine-rich protein kinase (SPAK) phosphorylates and activates SLC12A transporters such as the Na⁺-Cl⁻ cotransporter (NCC) and Na⁺-K⁺-2Cl⁻ cotransporter type 1 (NKCC1) and type 2 (NKCC2); these transporters have important roles in regulating BP through NaCl reabsorption and vasoconstriction. SPAK knockout mice are viable and display hypotension with decreased activity (phosphorylation) of NCC and NKCC1 in the kidneys and aorta, respectively. Therefore, agents that inhibit SPAK activity could be a new class of antihypertensive drugs with dual actions (i.e., NaCl diuresis and vasodilation). In this study, we developed a new ELISA-based screening system to find novel SPAK inhibitors and screened >20,000 small-molecule compounds. Furthermore, we used a drug repositioning strategy to identify existing drugs that inhibit SPAK activity. As a result, we discovered one small-molecule compound (Stock 1S-14279) and an antiparasitic agent (Closantel) that inhibited SPAK-regulated phosphorylation and activation of NCC and NKCC1 in vitro and in mice. Notably, these compounds had structural similarity and inhibited SPAK in an ATP-insensitive manner. We propose that the two compounds found in this study may have great potential as novel antihypertensive drugs.     

Cytomegalovirus cholangitis and pancreatitis in an immunocompetent patient

Cholangitis and pancreatitis associated with cytomegalovirus (CMV) infection in an immunocompetent patient is reported. Endoscopic retrograde cholangiography performed on a 55-year-old man for evaluation of the cause of jaundice and liver dysfunction revealed a distal focal irregular narrowing of the common bile duct. Microscopic findings of the resected specimen showed chronic cholangitis and CMV pancreatitis. Immunohistochemistry disclosed that epithelial cells in the inflamed bile duct were positive for CMV antigen, which was compatible with CMV cholangitis. Inflammation of the biliary tract or pancreas by CMV has been commonly reported as a complication in immunocompromised patients. Our report appears to be a rare case, but suggests that CMV cholangitis or pancreatitis should be considered in the differential diagnoses of common bile duct stenosis or pancreatitis even in immunocompetent individuals.