Localized turbulence structures in transitional rectangular-duct flow

Direct numerical simulations of transitional flow in a rectangular duct of cross-sectional aspect ratio A≡s/h=1–9 (s and h being the duct half-span and half-height, respectively) have been performed in the Reynolds number range Re≡ubh/ν=650–1500 (ub and ν being the bulk velocity and the kinematic viscosity, respectively) in order to investigate the dependence on the aspect ratio of spatially localized turbulence structures. It was observed that the lowest Reynolds number ReT, estimated in a specific way, for localized (transiently sustaining) turbulence decreases monotonically from ReT=730 for A=1 (square duct) with increasing aspect ratio, and for A=5 it nearly attains a minimal value ReT≈670 that is consistent with the onset Reynolds number of turbulent spots in a plane channel (A=∞). Turbulent states consist of localized structures that undergo a fundamental change around A=4. At Re=ReT turbulence for A=1–3 is streamwise-localized similar to turbulent puffs in pipe flow, while for A=5–9 turbulence at Re=ReT is also localized in the spanwise direction, similar to turbulent spots in plane channel flow. This structural change in turbulent states at Re=ReT is attributed to the exclusion of turbulence from the vicinity of the duct sidewalls in the case of a wide duct with A≳4: here the friction length on the sidewalls is so long that the size (around 100 times the friction length) of a self-sustaining minimal flow unit of streamwise vortices and streaks is larger than the duct height and, therefore, it cannot be accommodated

Decreased sensory nerve excitation and bone pain associated with mouse Lewis lung cancer in TRPV1-deficient mice

Bone pain is one of the most common and life-limiting complications of cancer metastasis to bone. Although the mechanism of bone pain still remains poorly understood, bone pain is evoked as a consequence of sensitization and excitation of sensory nerves (SNs) innervating bone by noxious stimuli produced in the microenvironment of bone metastases. We showed that bone is innervated by calcitonin gene-related protein (CGRP)+ SNs extending from dorsal root ganglia (DRG), the cell body of SNs, in mice. Mice intratibially injected with Lewis lung cancer (LLC) cells showed progressive bone pain evaluated by mechanical allodynia and flinching with increased CGRP+ SNs in bone and augmented SN excitation in DRG as indicated by elevated numbers of pERK- and pCREB-immunoreactive neurons. Immunohistochemical examination of LLC-injected bone revealed that the tumor microenvironment is acidic. Bafilomycin A1, a selective inhibitor of H+ secretion from vacuolar proton pump, significantly alleviated bone pain, indicating that the acidic microenvironment contributes to bone pain. We then determined whether the transient receptor potential vanilloid 1 (TRPV1), a major acid-sensing nociceptor predominantly expressed on SNs, plays a role in bone pain by intratibially injecting LLC cells in TRPV1-deficient mice. Bone pain and SN excitation in the DRG and spinal dorsal horn were significantly decreased in TRPV1 −/− mice compared with wild-type mice. Our results suggest that TRPV1 activation on SNs innervating bone by the acidic cancer microenvironment in bone contributes to SN activation and bone pain. Targeting acid-activated TRPV1 is a potential therapeutic approach to cancer-induced bone pain

Enlargement of accessory spleen subsequent to splenectomy associated with gastrectomy can mimic a solitary tumor : report of a case

We report a case of a 65-year-old woman with an incidental about 20-mm solitary mass between the lateralsegment of the left lobe of the liver and left kidney 5 years after splenectomy associated with total gastrectomy. The mass wassurgically resected, and histological examination revealed it to be an accessory spleen. Small accessory spleens mostly locatednear the splenic hilus, but large accessory spleens are unusual after total gastrectomy with regional lymph nodes resection. Theremaining accessory splenic tissue would undergo compensatory hypertrophy. Hence, the possibility of accessory spleens mustbe considered when an intra-abdominal mass is identified in a patient with splenectomy associated with gastrectomy

Bone pain induced by multiple myeloma is reduced by targeting V-ATPase and ASIC3

Multiple myeloma (MM) patients experience severe bone pain (MMBP) that is undertreated and poorly understood. In this study, we studied MMBP in an intratibial mouse xenograft model which employs JJN3 human MM cells. In this model, mice develop MMBP associated in bone with increased sprouting of calcitonin gene-related peptide-positive (CGRP+) sensory nerves and in dorsal root ganglia (DRG) with upregulation of phosphorylated ERK1/2 (pERK1/2) and pCREB, two molecular indicators of neuron excitation. We found that JJN3 cells expressed a vacuolar proton pump (V-ATPase) that induced an acidic bone microenvironment. Inhibition of JJN3-colonized bone acidification by a single injection of the selective V-ATPase inhibitor, bafilomycin A1, decreased MMBP, CGRP+ SN sprouting, and pERK1/2 and pCREB expression in DRG. CGRP+ sensory nerves also expressed increased levels of the acid-sensing nociceptor ASIC3. Notably, a single injection of the selective ASIC3 antagonist APETx2 dramatically reduced MMBP in the model. Mechanistic investigations in primary DRG neurons co-cultured with JJN3 cells showed increased neurite outgrowth and excitation inhibited by bafilomycin A1 or APETx2. Further, combining APETx2 with bafilomycin A1 reduced MMBP to a greater extent than either agent alone. Lastly, combining bafilomycin A1 with the osteoclast inhibitor zoledronic acid was sufficient to ameliorate MMBP which was refractory to zoledronic acid. Overall, our results show that osteoclasts and MM cooperate to induce an acidic bone microenvironment that evokes MMBP as a result of the excitation of ASIC3-activated sensory neurons. Further, they present a mechanistic rationale for targeting ASIC3 on neurons along with the MM-induced acidic bone microenvironment as a strategy to relieve MMBP in patients

The Synthetic Curcumin Analogue GO-Y030 Effectively Suppresses the Development of Pressure Overload-induced Heart Failure in Mice

Curcumin is a naturally occurring p300-histone acetyltransferase (p300-HAT) inhibitor that suppresses cardiomyocyte hypertrophy and the development of heart failure in experimental animal models. To enhance the therapeutic potential of curcumin against heart failure, we produced a series of synthetic curcumin analogues and investigated their inhibitory activity against p300-HAT. The compound with the strongest activity was further evaluated to determine its effects on cardiomyocyte hypertrophy and pressure overload-induced heart failure in mice. We synthesised five synthetic curcumin analogues and found that a compound we have named GO-Y030 most strongly inhibited p300-HAT activity. Furthermore, 1 μM GO-Y030, in a manner equivalent to 10 µM curcumin, suppressed phenylephrine-induced hypertrophic responses in cultured cardiomyocytes. In mice undergoing transverse aortic constriction surgery, administration of GO-Y030 at a mere 1% of an equivalently-effective dose of curcumin significantly attenuated cardiac hypertrophy and systolic dysfunction. In addition, this low dose of GO-Y030 almost completely blocked histone H3K9 acetylation and eliminated left ventricular fibrosis. A low dose of the synthetic curcumin analogue GO-Y030 effectively inhibits p300-HAT activity and markedly suppresses the development of heart failure in mice

The exacerbation risk prediction by fractional exhaled nitric oxide in younger and elder children with bronchial asthma

The usefulness of the Fractional exhaled nitric oxide (FeNO) measurements for asthma exacerbation risk prediction in asthmatic children is controversial. Fifty-seven asthmatic children who were regularly treated and had previously been stable for at least 3 months were enrolled. The asthma excerbations risk prediction by the FeNO levels and age contribution on it were investigated. As analyzed all the patients, FeNO cut off value for the significant risk of asthma exacerbation was 36.9 ppb (risk odds was 5.1 [95% C.I., 1.8 to 15.0], chi square valve = 9.0, p=0.0028). However, sensitivity and specificity were not adequate for predicting asthma exacerbation (Sensitivity, 77.8%; Specificity, 59.9%; Area under the curve [AUC], 0.674). These parameters were improved only when 6-10 year old children were assessed (FeNO threshold=39.9 ppb, risk odds=10.2 [3.1 to 33.1], chi square valve 14.8, p=0.0001); Sensitivity, 80.8%; Specificity, 71.8%; AUC, 0.758). High value of FeNO is a risk factor for the asthma exacerbation, and FeNO measurement may be more useful for asthma control in younger children than elder asthmatic children

Clopidogrel Monotherapy After 1-Month Dual Antiplatelet Therapy in Percutaneous Coronary Intervention: From the STOPDAPT-2 Total Cohort

[Background:] The benefit of clopidogrel monotherapy after 1-month dual antiplatelet therapy (DAPT) compared with 12-month DAPT with aspirin and clopidogrel was demonstrated in the STOPDAPT-2 (Short and Optimal Duration of Dual Antiplatelet Therapy After Everolimus-Eluting Cobalt-Chromium Stent-2), but not in the STOPDAPT-2 acute coronary syndrome (ACS); however, both trials were underpowered based on the actual event rates. [Methods:] We obtained the prespecified pooled population of 5997 patients as the STOPDAPT-2 total cohort (STOPDAPT-2: N=3009/STOPDAPT-2 ACS: N=2988; ACS: N=4136/chronic coronary syndrome [CCS]: N=1861), comprising 2993 patients assigned to 1-month DAPT followed by clopidogrel monotherapy, and 3004 patients assigned to 12-month DAPT with aspirin and clopidogrel after percutaneous coronary intervention. The primary end point was the composite of cardiovascular (cardiovascular death, myocardial infarction, definite stent thrombosis, or any stroke) or bleeding (Thrombolysis in Myocardial Infarction major/minor) end points at 1 year. [Results:] One-month DAPT was noninferior to 12-month DAPT for the primary end point (2.84% versus 3.04%; hazard ratio [HR], 0.94 [95% CI, 0.70–1.27]; Pnoninferiority=0.001; Psuperiority=0.68). There was no significant risk-difference for the cardiovascular end point between the 1- and 12-month DAPT groups (2.40% versus 1.97%; HR, 1.24 [95% CI, 0.88–1.75]; Pnoninferiority=0.14; Psuperiority=0.23). There was a lower risk of the bleeding end point with 1-month DAPT relative to 12-month DAPT (0.50% versus 1.31%; HR, 0.38 [95% CI, 0.21–0.70]; Psuperiority=0.002). One-month DAPT relative to 12-month DAPT was associated with a lower risk for major bleeding regardless of ACS or CCS (ACS: HR, 0.46 [95% CI, 0.23–0.94]; P=0.03, and CCS: HR, 0.26 [95% CI, 0.09–0.79]; P=0.02; Pinteraction=0.40), while it was associated with a numerical increase in cardiovascular events in ACS patients, but not in CCS patients, although not statistically significant and without interaction (ACS: HR, 1.50 [95% CI, 0.99–2.27]; P=0.053, and CCS: HR, 0.74 [95% CI, 0.38–1.45]; P=0.39; Pinteraction=0.08). [Conclusions:] Clopidogrel monotherapy after 1-month DAPT compared with 12-month DAPT with aspirin and clopidogrel had a benefit in reducing major bleeding events without being associated with increase in cardiovascular events

Clopidogrel Monotherapy After 1-Month DAPT in Patients With High Bleeding Risk or Complex PCI

BACKGROUND: High bleeding risk (HBR) and complex percutaneous coronary intervention (PCI) are major determinants for dual antiplatelet therapy (DAPT) duration. OBJECTIVES: The aim of this study was to evaluate the effects of HBR and complex PCI on short vs standard DAPT. METHODS: Subgroup analyses were conducted on the basis of Academic Research Consortium-defined HBR and complex PCI in the STOPDAPT-2 (Short and Optimal Duration of Dual Antiplatelet Therapy After Verulam's-Eluting Cobalt-Chromium Stent-2) Total Cohort, which randomly compared clopidogrel monotherapy after 1-month DAPT with 12-month DAPT with aspirin and clopidogrel after PCI. The primary endpoint was the composite of cardiovascular (cardiovascular death, myocardial infarction, definite stent thrombosis, or stroke) or bleeding (Thrombolysis In Myocardial Infarction [TIMI] major or minor) endpoints at 1 year. RESULTS: Regardless of HBR (n = 1, 893 [31.6%]) and complex PCI (n = 999 [16.7%]), the risk of 1-month DAPT relative to 12-month DAPT was not significant for the primary endpoint (HBR, 5.01% vs 5.14%; non-HBR, 1.90% vs 2.02%; P interaction = 0.95) (complex PCI, 3.15% vs 4.07%; noncomplex PCI, 2.78% vs 2.82%; P interaction = 0.48) and for the cardiovascular endpoint (HBR, 4.35% vs 3.52%; and non-HBR, 1.56% vs 1.22%; P interaction = 0.90) (complex PCI, 2.53% vs 2.52%; noncomplex PCI, 2.38% vs 1.86%; P interaction = 0.53), while it was lower for the bleeding endpoint (HBR, 0.66% vs 2.27%; non-HBR, 0.43% vs 0.85%; P interaction = 0.36) (complex PCI, 0.63% vs 1.75%; noncomplex PCI, 0.48% vs 1.22%; P interaction = 0.90). The absolute difference in the bleeding between 1- and 12-month DAPT was numerically greater in patients with HBR than in those without HBR (-1.61% vs -0.42%). CONCLUSIONS: The effects of 1-month DAPT relative to 12-month DAPT were consistent regardless of HBR and complex PCI. The absolute benefit of 1-month DAPT over 12-month DAPT in reducing major bleeding was numerically greater in patients with HBR than in those without HBR. Complex PCI might not be an appropriate determinant for DAPT durations after PCI. (Short and Optimal Duration of Dual Antiplatelet Therapy After Everolimus-Eluting Cobalt-Chromium Stent-2 [STOPDAPT-2], NCT02619760; Short and Optimal Duration of Dual Antiplatelet Therapy After Everolimus-Eluting Cobalt-Chromium Stent-2 for the Patients With ACS [STOPDAPT-2 ACS], NCT03462498)