[Steroid resistance of severe asthma - mechanisms and therapeutic targets].

Asthma therapy in general has improved a lot in recent years, but it is still a major problem that severe asthma, which accounts for 10 to 20%, still suffers from strong symptoms on a daily basis despite all therapeutic agents used in combination. American SARP and European ENFUMOSA started in 2000 to advance pathophysiological insights of severe asthma. Clinical usage of antibodies and inhibitors against IgE, TNF, IL-5, IL-4, IL-13, and TSLP are also accumulating. Some of these molecular-targeted drugs improve respiratory function and reduce acute exacerbations in patients with severe asthma. Until now, cytokines have been assumed to be involved in chronic inflammation, but it is also interesting to elucidate the pathways of how cytokines are involved in respiratory function and acute exacerbations. We registered approximately 100 steroid-dependent asthma patients in Japan. Although long-lasting poor control of the disease was considered the cause of severe asthma in the past, steroid dependence in one third of the cases occurred within 2-3 years after the onset. Steroid resistance seems a key process from the early stage of the disease. Steroid resistance of T cell level was induced by extracellular co-stimulation and cytokine signals. The inhibition may improve steroid sensitivity and treat steroid-resistant asthma. Therefore, we established a steroid-resistant asthma model for the first time by transferring steroid resistant T cell clones, and analyzed the steroid sensitivity recovery effect of CTLA4-Ig. In addition, a multicenter, double-blind, placebo-controlled exploratory trial was performed as a POC study investigating the efficacy of abatacept in treatment-resistant severe asthma. Elucidation of the pathophysiology and mechanism by which steroids do not work is expected to be a breakthrough for the prevention and treatment of severe asthma.

Low-dose mepolizumab is effective as an add-on therapy for treating long-lasting peripheral neuropathy in patients with eosinophilic granulomatosis with polyangiitis.

OBJECTIVE: To assess the effectiveness of low-dose mepolizumab as an add-on therapy for treating peripheral neurological symptoms in eosinophilic granulomatosis with polyangiitis (EGPA). METHODS: We prospectively studied 13 EGPA patients with conventional treatment-resistant peripheral neuropathy. Their symptoms (pain, numbness, and muscle weakness) were assessed on a visual analogue scale (VAS) before and after 12 months of mepolizumab therapy (100 mg every 4 weeks). Peripheral eosinophil levels and several biomarkers including urinary levels of eosinophil-derived neurotoxin (EDN) were measured before and after therapy. RESULTS: VAS scores for pain and numbness significantly improved after 12 months of mepolizumab therapy (from 67.0 to 48.0, P = 0.012, and from 67.0 to 51.0, P = 0.017, respectively). However, the VAS score for muscle weakness did not improve (P = 0.36). There were significant correlations between treatment-related changes in urinary EDN levels from baseline to 6 months later and percent changes in the VAS scores of pain and numbness (r = 0.75, P = 0.020; r = 0.88, P = 0.002). CONCLUSIONS: Treatment-resistant peripheral neuropathy in EGPA was significantly improved by low-dose mepolizumab, and effectiveness was correlated with decreased urinary EDN. Because the possibility of a placebo effect cannot be formally excluded, placebo-controlled studies will be required in the future.

Emergent transcatheter arterial embolization for norovirus-associated life-threatening ulcer bleeding to achieve successful hemostasis in 2-year-old boy.

Case: We report a 2-year-old boy with duodenal ulcer with active bleeding that occurred as a result of norovirus gastroenteritis. On admission, the patient presented with shock accompanied with vomiting and melena. Abdominal contrast enhanced computed tomography scan showed signs of duodenal bleeding. Outcome: He was successfully treated with emergent transcatheter arterial embolization. After the treatment, endoscopic examination revealed duodenal ulcer and the stool norovirus antigen test was found to be positive. The patient recovered completely without any sequelae. Conclusion: Life-threatening duodenal ulcer bleeding in children can be caused by viral gastroenteritis. When endoscopic therapy is unsuccessful or difficult, in cases of small children, angiographic intervention can be a safe alternative treatment option of gastrointestinal bleeding.

Left ventricular diastolic dysfunction in normotensive diabetic patients in various age strata.

Although patients with type 2 diabetes demonstrate cardiac diastolic dysfunction, it is well known that cardiac diastolic dysfunction is produced by hypertension and aging. The purpose of the present study was to elucidate the cardiac structure and function in normotensive patients with type 2 diabetes in various age strata in order to assess the effect of diabetes mellitus itself on cardiac function. Echocardiographic examination was performed in 77 normotensive patients with type 2 diabetes (age: 63+/-11 years) and 76 healthy control subjects (age: 60+/-11 years) who were in their forties, fifties, sixties, and seventies. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) using the transmitral flow velocity, which were obtained by Doppler echocardiography. No difference was observed in the relative wall thickness, LV mass index, or LVEF between the diabetic patients and control subjects in any of the age strata. The E/A ratio in the patients with type 2 diabetes was not different from that in the control subjects in their 40s (1.17+/-0.35 versus 1.20+/-0.36). However, E/A was significantly lower in the diabetic patients than in the control subjects in their 50s (0.87+/-0.28 versus 1.14+/-0.24), 60s (0.78+/-0.22 versus 0.97+/-0.27), and 70s (0.66+/-0.19 versus 0.84+/-0.21) (p<0.05). The duration of type 2 diabetes was significantly longer in patients in their 50s (7.0+/-2.5 years), 60s (8.0+/-3.2 years), and 70s (10.4+/-3.2 years) than in patients in their 40s (3.3+/-1.9 years) (p<0.001). The value of E/A in the diabetic patients correlated with the duration of type 2 diabetes (r=-0.62, p<0.001). These results indicate that cardiac diastolic dysfunction without LV systolic dysfunction in patients with well-controlled type 2 diabetes is related neither to hypertension nor LV hypertrophy, but rather to aging and the duration of type 2 diabetes.

Juvenile hormone activity of ethyl 4-(2-aryloxyhexyloxy)benzoates with precocious metamorphosis-inducing activity.

Ethyl 4-[2-(6-methyl-3-pyridyloxy)hexyloxy]benzoate (1) and ethyl 4-(2-phenoxyhexyloxy)benzoate (2), which induce precocious metamorphosis in larvae of Bombyx mori, a clear sign of juvenile hormone (JH) deficiency, showed JH activity when topically applied to allatectomized 4th instar larvae of B. mori. Compounds 1 and 2 induced precocious metamorphosis with doses at which they were effective as JH agonists.

Cardiac function as assessed by echocardiography in the oldest old > or = 90 years of age.

Although several studies have demonstrated that cardiac diastolic function is impaired but cardiac systolic function is preserved with aging, no large-scale analysis of cardiac function by echocardiography in subjects aged > or = 90 years exists. The purpose of the present study was to elucidate the cardiac structure and function in the oldest old in order to assess the effect of aging on cardiac function. Echocardiographic examination was performed in 1793 subjects who were in their fifties, sixties, seventies, eighties, and nineties. Left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. LV ejection fraction (LVEF) was calculated and used as the parameter representing LV systolic function. LV diastolic function was assessed using the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial contraction (A velocity), and the ratio of E to A (E/A) by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. The E/A decreased progressively with aging, and demonstrated the closest correlation with age among all the indexes of cardiac function (r = -0.44, P < 0.001). In contrast, LVEF and the Tei index demonstrated a very weak correlation with age (r = -0.13, P < 0.001 and r = 0.16, P < 0.001, respectively). The mean value for LVEF remained normal with aging in all age strata (50s: 71 +/- 8%, 60s: 71 +/- 8%, 70s: 70 +/- 9%, and 80s: 71 +/- 10%), but decreased significantly in subjects in their 90s (66 +/- 10%, P < 0.001). In addition, the mean value for the Tei index also remained normal with aging in subjects in their 50s (0.35 +/- 0.10), 60s (0.38 +/- 0.14), 70s (0.38 +/- 0.12), and 80s (0.39 +/- 0.15), but showed an abnormal value in subjects in their 90s (0.45 +/- 0.12, P < 0.001). In conclusion, both diastolic dysfunction and systolic dysfunction with advancing age were observed in the oldest old aged > or = 90 years. The age-related impairment of systolic function as well as diastolic function should be considered when echocardiography is used to evaluate the causes of heart failure in the oldest old.

Latent cardiac dysfunction as assessed by echocardiography in bed-bound patients following cerebrovascular accidents: comparison with nutritional status.

The aim of this study was to elucidate the cardiac function in bed-bound patients following cerebrovascular accidents. In accord with the criteria for activities of daily living (ADL) of the Japanese Ministry of Health, Labour and Welfare, 51 age-matched poststroke patients without heart disease were classified into 3 groups: rank A (house-bound) (n = 16, age, 85 +/- 6 years), rank B (chair-bound) (n = 16, age, 84 +/- 8 years), and rank C (bed-bound) (n = 19, age, 85 +/- 9 years). Using echocardiography, the left ventricular (LV) diastolic function was assessed by the ratio of early filling (E) and atrial contraction (A) transmitral flow velocities (E/A) of LV inflow. LV systolic function was assessed by LV ejection fraction (LVEF), and the Tei index was also measured to assess both LV systolic and diastolic function. No difference was observed in the E/A and LVEF among the 3 groups. The Tei index was higher in rank C (0.56 +/- 0.17) than in rank A (0.39 +/- 0.06) and rank B (0.48 +/- 0.17), and a statistically significant difference was observed between rank A and rank C (P < 0.05). Serum albumin and blood hemoglobin were significantly lower in rank C (3.1 +/- 0.4 and 10.6 +/- 1.8 g/dL) than in rank A (4.1 +/- 0.3 and 12.4 +/- 1.2 g/dL) (P < 0.001 and P < 0.05, respectively). These results indicate that latent cardiac dysfunction and poor nutritional status may exist in bed-bound patients (rank C) following cerebrovascular accidents. The Tei index may be a useful index of cardiac dysfunction in bed-bound patients because it is independent of the cardiac loading condition.

Left ventricular diastolic dysfunction as assessed by echocardiography in metabolic syndrome.

The purpose of the present study was to elucidate the cardiac structure and function in patients who have metabolic syndrome but no history of cardiovascular disease by analyzing echocardiographic findings. Echocardiographic examination was performed to screen for cardiovascular disease in 135 patients who were in their sixties. Patients were divided into metabolic syndrome (n=65, age: 65+/-2.7 years) and non-metabolic syndrome (n=70, age: 66+/-2.5 years) groups based on the criteria for metabolic syndrome proposed by the Japanese Society of Hypertension and seven other societies in 2005. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) was assessed by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. There were no differences in relative wall thickness, LV mass index, or LVEF between the two groups. However, both the EIA and Tei index were significantly different between the metabolic syndrome (0.66+/-0.14 and 0.36+/-0.07, respectively) and non-metabolic syndrome (0.88+/-0.25 and 0.29+/-0.09) groups (p<0.001). These results indicate that patients with metabolic syndrome can have cardiac diastolic dysfunction even if they have neither LV hypertrophy nor systolic dysfunction.

Spatial distribution of right ventricular perfusion abnormalities following acute right coronary artery occlusion: a study by myocardial contrast echocardiography and blue dye staining.

OBJECTIVE: Although echocardiography is used for diagnosing right ventricular (RV) infarction produced by right coronary artery (RCA) occlusion, there has been no data on the spatial distribution of RV perfusion abnormalities following acute RCA occlusion. We examined this distribution by myocardial contrast echocardiography (MCE) and blue dye staining in canine models. METHODS: The RCA was occluded in 10 open-chest dogs. MCE was performed with 0.27 g/min Levovist infusion by harmonic power Doppler with electrocardiogram gated intermittent triggered imaging at baseline and at 90 min after RCA occlusion. The opacification defects were assessed at the basal, middle, and apical levels of the RV free wall by short-axis view. The extent of the risk area of the occluded RCA, expressed as a percentage of the RV free wall, was measured at each level by injecting blue dye at the end of the experiments. In 10 other dogs, the left anterior descending coronary artery (LAD) was occluded by ligating the proximal portion of the LAD to examine the territory of the LAD on the same levels of the RV free wall by injecting blue dye. RESULTS: Although patchy opacification defects accompanying RV dilation were observed at the basal and middle levels during RCA occlusion, no apical defects were observed in any dogs by MCE. The risk area of the occluded RCA, as delineated by blue dye, was larger in the basal than apical level of the RV free wall in all 10 dogs (basal: 79 +/- 9%; middle: 48 +/- 14%; apical: 3 +/- 6%, p < 0.0001). The risk area of the occluded LAD (basal: 17 +/- 7%; middle: 12 +/- 6%; apical: 6 +/- 6%) was smaller than the risk area of the occluded RCA at the basal and middle levels of the RV free wall (p < 0.0001), and no significant difference was observed at the apical level. CONCLUSIONS: RV perfusion abnormalities produced by RCA occlusion are larger in the basal than apical level of the RV free wall. This finding elucidates the spatial distribution of the territory of the RCA on the RV free wall, and may help in identifying and assessing RV ischemia by echocardiography in humans. Moreover, the data in the current study indicate that RV infarction may be produced by occlusion of the coronary arteries except RCA, because the territory of the LAD on the RV free wall is clearly delineated.

Ethyl 4-[2-(6-Methyl-3-pyridyloxy)butyloxy]benzoate, a novel anti-juvenile hormone agent.

Ethyl 4-[2-(6-methyl-3-pyridyloxy)butyloxy]benzoate (2) was prepared as a novel anti-juvenile hormone (anti-JH) agent. Compound 2 induced precocious metamorphosis in larvae of the silkworm and black pigmentation of the larval cuticle, which are clearly recognized as JH-deficiency symptoms. The 4-ethoxycarbonyl group on the benzene ring was indispensable for activity. The activity of compound 2 could be fully counteracted by methoprene, a JH agonist, but not by the dietary administration of 20-hydroxyecdysone.

Assessment of right ventricular perfusion after right coronary artery occlusion by myocardial contrast echocardiography.

OBJECTIVES: The purpose of this study was to examine the ability of myocardial contrast echocardiography (MCE) to assess right ventricular (RV) perfusion. BACKGROUND: Although MCE can readily assess left ventricular perfusion abnormalities, there are no data regarding the ability to assess RV perfusion abnormalities. METHODS: The right coronary artery (RCA) was occluded in 10 open-chest dogs. Myocardial contrast echocardiography was performed with 0.27 g/min Levovist infusion by harmonic power Doppler with electrocardiographically gated intermittent triggered imaging at pulsing intervals ranging from 1:1 to 1:20 at baseline and 90 min after RCA occlusion. Video-intensity of the RV wall was plotted against pulsing intervals and was fitted to an exponential function: y = A(1-exp(-bt)), where A is the plateau video-intensity and b is the rate of video-intensity rise. Myocardial contrast echocardiography and microsphere-derived myocardial blood flow (MBF) measurements were performed at baseline and 90 min after RCA occlusion. RESULTS: Because the severity of RV perfusion abnormalities assessed by MBF varied during RCA occlusion, diverse grades of patchy opacification defects were observed by MCE. The RV wall thickness decreased, and the RV dimension increased, after RCA occlusion in each dog. The correlation of occlusion to baseline MBF ratios in the RV wall was closer to the ratio of b (r = 0.897, p = 0.0004) than A (r = 0.767, p = 0.0097) and was the closest to the ratio of Axb (r = 0.935, p < 0.0001). CONCLUSIONS: The RCA occlusion is manifested by RV wall thinning and dilation as well as by perfusion abnormalities consisting of patchy opacification defects by MCE. Myocardial contrast echocardiography-derived refilling parameters can be applied to assess RV perfusion abnormalities produced by RCA occlusion.