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Background: Cardiovascular disease (CVD) is an inflammatory disorder enhanced by diabetes. The mechanisms by which recurrent acute hyperglycemia promotes inflammation and CVD are unclear. We showed that acute hyperglycemia mediates increased monocyte cholesterol uptake and cytokine release, but the underlying signaling pathways are unknown. We hypothesized that acute hyperglycemia-induced oxidative and ER stress in circulating monocytes increases cholesterol uptake and a pro-inflammatory phenotype. Methods: Circulating monocytes from 35 healthy subjects were isolated and exposed to euglycemic (5mM) or hyperglycemic (16.7 mM) conditions with or without inhibitors of ER stress (4 phenyl butyric acid) or oxidative stress (N-Acetyl cysteine) for 2 or 6 hrs to assess changes in LDL or oxLDL uptake and cytokine (TNF-α, IL1-β) release. Results: We found that acute hyperglycemia-induced ER and oxidative stress increased total and free cholesterol content via enhanced LDL (18% and 26%, p Conclusion: Recurrent acute hyperglycemia promotes inflammation by increasing monocyte ER and oxidative stress, which accelerates cholesterol uptake, cholesterol deposition, and cytokine secretion. Future studies are needed to test if acute hyperglycemia-induced monocyte cholesterol deposition is a mechanism to contribute to increased CVD in diabetes. Disclosure R.Zhang: Research Support; American Heart Association. J.Oh: None. G.A.Kutz: None. M.Bambouskova: None. A.S.Dusso: None. C.Bernal-mizrachi: None.

Atypical hemolytic uremic syndrome (aHUS) is a rare syndrome characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute renal injury, which results from uncontrolled complement activation. Delayed diagnosis and treatment of aHUS may result in end-stage renal disease (ESRD) and an associated dependence on dialysis. In extreme cases, it may cause death due to multi-organ failure. Eculizumab, a humanized monoclonal antibody against C5, inhibits the formation of the terminal membrane attack complex and is used to treat aHUS. Here, we report a 46-year-old male patient who suffered from aHUS relapse, despite prior treatment with repeated plasma exchange and hemodialysis. Eculizumab therapy improved his hematologic findings without use of hemodialysis. (Korean J Med 2020;95:124-128)

We examined the effects of empagliflozin, a selective inhibitor of Na+-glucose cotransporter 2, on mitochondrial quality control and autophagy in renal tubular cells in a diabetic environment in vivo and in vitro. Human renal proximal tubular cells (hRPTCs) were incubated under high-glucose conditions. Diabetes was induced with streptozotocin in male C57BL/6J mice. Improvements in mitochondrial biogenesis and balanced fusion-fission protein expression were noted in hRPTCs after treatment with empagliflozin in high-glucose media. Empagliflozin also increased autophagic activities in renal tubular cells in the high-glucose environment, which was accompanied with mammalian target of rapamycin inhibition. Moreover, reduced mitochondrial reactive oxygen species production and decreased apoptotic and fibrotic protein expression were observed in hRPTCs after treatment with empagliflozin, even in the hyperglycemic circumstance. Importantly, empagliflozin restored AMP-activated protein kinase-α phosphorylation and normalized levels of AMP-to-ATP ratios in hRPTCs subjected to a high-glucose environment, which suggests the way that empagliflozin is involved in mitochondrial quality control. Empagliflozin effectively suppressed Na+-glucose cotransporter 2 expression and ameliorated renal morphological changes in the kidneys of streptozotocin-induced diabetic mice. Electron microscopy analysis showed that mitochondrial fragmentation was decreased and 8-hydroxy-2′-deoxyguanosine content was low in renal tubular cells of empagliflozin treatment groups compared with those of the diabetic control group. We suggest one mechanism related to the renoprotective actions of empagliflozin, which reverse mitochondrial dynamics and autophagy.

Interpolation inequalities in Triebel-Lizorkin-Lorentz spaces and Besov-Lorentz spaces are studied for both inhomogeneous and homogeneous cases. First we establish interpolation inequalities under quite general assumptions on the parameters of the function spaces. Several results on necessary conditions are also provided. Next, utilizing the interpolation inequalities together with some embedding results, we prove Gagliardo-Nirenberg inequalities for fractional derivatives in Lorentz spaces, which do hold even for the limiting case when one of the parameters is equal to 1 or $\infty$., Comment: 47 pages

Myeloid cells are known mediators of hypertension, but their role in initiating renin-induced hypertension has not been studied. Vitamin D deficiency causes pro-inflammatory macrophage infiltration in metabolic tissues and is linked to renin-mediated hypertension. We tested the hypothesis that impaired vitamin D signaling in macrophages causes hypertension using conditional knockout of the myeloid vitamin D receptor in mice (KODMAC). These mice develop renin-dependent hypertension due to macrophage infiltration of the vasculature and direct activation of renal juxtaglomerular (JG) cell renin production. Induction of endoplasmic reticulum stress in knockout macrophages increases miR-106b-5p secretion, which stimulates JG cell renin production via repression of transcription factors E2f1 and Pde3b. Moreover, in wild-type recipient mice of KODMAC/miR106b−/− bone marrow, knockout of miR-106b-5p prevents the hypertension and JG cell renin production induced by KODMAC macrophages, suggesting myeloid-specific, miR-106b-5p-dependent effects. These findings confirm macrophage miR-106b-5p secretion from impaired vitamin D receptor signaling causes inflammation-induced hypertension., Myeloid cells are involved in hypertension, but their exact role in renin-induced hypertension remains unclear. Here the authors show that impaired vitamin D signaling in myeloid cells causes hypertension via macrophage-specific miR-106b-5p secretion, which activates renin production in the kidney.

Ethnopharmacological relevance Artemisia scoparia Waldst. & Kitam (A. scoparia) is a perennial herbal plant that is widely used as a folk remedy in Asian countries. Several studies have demonstrated that A. scoparia has various physiological effects, including anti-inflammation, anti-hypertension, anti-obesity, anti-hepatotoxicity, and anti-oxidant effects. Aim of the study: The objective of the present study was to examine the anti-inflammatory effects of water extract of A. scoparia (WAS). Materials and methods Murine bone marrow-derived macrophages (BMDMs), human monocyte THP-1 and murine fibroblast 3T3-L1 cells were used for the in vitro experiments. Cell viability and cytokine production were determined by the MTT assay and ELISA, respectively. RT-PCR was performed to determine iNOS gene expression and the Griess reaction was used to measure nitrite levels. iNOS protein expression, activation of NF-κB and MAPKs, and cleavage of caspase-1 and IL-1β were determined by Western blot analysis. A carrageenan-induced mouse model of acute inflammation was used in the in vivo experiments. Results Pretreatment with WAS concentration-dependently suppressed gene expression and IL-6, TNF-α, CXCL1 and iNOS protein levels in BMDMs stimulated with LPS. In addition, pretreatment with WAS inhibited LPS-induced production of IL-6 and TNF-α in THP-1 cells and CXCL1 in 3T3-L1. Furthermore, LPS induced phosphorylation of p65 in BMDMs, and this induction was dramatically suppressed by WAS pretreatment. We further investigated whether WAS regulates activation of the NLRP3 inflammasome, which is known to be essential for IL-1β processing. WAS inhibited the production of IL-1β, but not IL-6, in response to adenosine triphosphate (ATP) and monosodium uric acid (MSU) crystals in LPS-primed BMDMs. Cleavage of caspase-1 and IL-1β was also reduced by WAS. We finally evaluated the in vivo anti-inflammatory effects of WAS in a mouse model of carrageenan-induced acute inflammation. Subcutaneous administration of WAS reduced production of the inflammatory cytokines IL-6, TNF-α, CXCL1, and IL-1β. Recruitment of immune cells, mostly neutrophils, was also reduced by administration of WAS. Infiltration of inflammatory cells and edema in the submucosa of air pouch tissues were markedly improved in the WAS-treated groups. Conclusions Our results indicate that WAS possesses potent anti-inflammatory properties. These findings suggest that A. scoparia is a candidate functional food targeting several inflammatory diseases.

Background: Type 2 diabetes is linked to accelerated atherosclerosis, however the mechanisms behind this association are unclear. Inadequate glycemic control is an important contributor for cardiovascular disease (CVD). Episodic hyperglycemia as a surrogate for glycemic variability (GV) promotes monocyte adhesion and increases proinflammatory monocytes within plaques of patients with diabetes. Monocytes are precursors to macrophages which play a vital role in atherosclerosis and are capable of delivering cholesterol content to plaques. Therefore, elucidating the mechanism by which acute hyperglycemia promotes proatherogenic monocytes in diabetes can lead to novel therapies slowing atherosclerosis progression in these patients. Methods: To assess the effects of acute hyperglycemia on monocyte cholesterol metabolism, we isolated monocytes from 28 patients with Type 2 diabetes cultured for 2 and 6 hours in normoglycemic (90mg/dL) or hyperglycemic media (300mg/dL). Cholesterol content was measured by lipid extraction and fluorometric cholesterol oxidase assay. Cholesterol uptake was assessed by incubating monocytes with Dil-oxidized LDL (Dil-OxLDL). Cholesterol synthesis was performed by incubating monocytes with 2-14C-Acetate in both glycemic conditions for 6 hours followed by lipid saponification, and separated via TLC on silica gel plates. Cholesterol efflux was assessed by labeling cells with 3H-Cholesterol-OxLDL in both glycemic conditions for 6 hours followed by APO-A1 or HDL stimulation for 4 hours. Results: Acute hyperglycemia for 2 and 6 hours induced foamy monocytes with increased total cholesterol content (22 and 32%, respectively), cholesterol ester (40% and 43%, respectively), and free cholesterol content (14% and 25%, respectively) due to enhanced DiI-OxLDL uptake. There was no significant increase in monocyte cholesterol synthesis or cholesterol efflux after stimulation with HDL or APO A-1. Conclusions: Increased monocyte cholesterol content during acute hyperglycemia is a potential mechanism promoting atherosclerosis in patients with Type 2 diabetes.

Six new 8-C-p-hydroxybenzylflavonol glycosides were isolated from a hot water extract of pumpkin (Cucurbita moschata Duch.) tendril and elucidated as 8-C-p-hydroxybenzylquercetin 3-O-rutinoside, 8-C-p-hydroxybenzoylquercetin 3-O-&beta, D-glucopyranoside, 8-C-p-hydroxybenzylkaempferol 3-O-(&alpha, L-rhamnopyranosyl(1&rarr, 6)-&beta, D-galactopyranoside, 8-C-p-hydroxybenzoylkaempferol 3-O-rutinoside, 8-C-p-hydroxybenzylisorhamnetin 3-O-rutinoside, and 8-C-p-hydroxybenzylisorhamnetin 3-O-(&alpha, D-galactopyranoside. Their chemical structures were determined using nuclear magnetic resonance (NMR) and electrospray ionization-mass spectrometer (ESIMS) analyses. The 8-C-p-hydroxybenzylflavonol glycosides were found to inhibit the receptor activator of nuclear factor-&kappa, B (RANKL)-induced osteoclast differentiation of bone marrow derived macrophage (BMDM), an osteoclast progenitor. Additionally, 8-C-p-hydroxybenzylflavonol glycosides effectively reduced the expression of osteoclast-related genes, such as tartrate-resistant acid phosphatase, cathepsin K, nuclear factor activated T-cell cytoplasmic 1, and dendritic cell specific transmembrane protein in RANKL-treated BMDMs. These results indicate that the 8-C-p-hydroxybenzylflavonol glycosides may be the main components responsible for the osteoclast differentiation inhibitory effect of pumpkin tendril.

Cross-sectional studies indicate consistent associations between low 25(OH)D concentration and increased risk of cardiovascular disease (CVD), but results of randomized control trials (RCTs) are mixed. However, the majority of the RCTs do not focus on type 2 diabetics, potentially obscuring the effects of vitamin D in this population. In vitro 1,25(OH)2D3 downregulates macrophage cholesterol deposition, but the in vivo effects are unknown. To explore potential mechanisms of the effects of vitamin D on CVD risk in patients with type 2 diabetes, we isolated monocytes in a subset of 26 patients from our RCT of diabetics with baseline serum 25(OH)D 50% reduction in the vitamin D group with no change in the placebo group. This was mediated through suppression of endoplasmic reticulum stress and scavenger receptor CD36 protein expression. The reduction in monocyte cholesterol uptake was reflected in a 19% decrease in total monocyte cholesterol content. Interestingly, cross-sectional analysis of circulating monocytes from vitamin D-deficient vs. sufficient diabetic patients revealed 8-fold higher cholesteryl ester content, confirming the capacity of these monocytes to uptake and carry cholesterol in the circulation. This study identifies a unique circulating cholesterol pool within monocytes that is modulated by vitamin D and has the potential to contribute to CVD in type 2 diabetes.

Chronic inflammation and local activation of the renin-angiotensin-aldosterone system (RAAS) play a pivotal role in the pathogenesis and progression of diabetic complications. In patients with type 2 diabetes (T2DM), the prevalence of vitamin D deficiency is almost twice that of non-diabetics, and vitamin d deficiency nearly doubles the risk of developing hypertension and cardiovascular complications compared to diabetics with normal vitamin D levels. Interestingly, mice lacking the vitamin D receptor (VDR) in macrophages (KODMAC) develop renin-dependent hypertension, insulin resistance, and inflammation via up-regulation of macrophage ER stress. Macrophages also express all major components of the RAAS system. However, little is known about the regulation of macrophage-generated renin and its role in modulating the sequelae of VDR signaling in macrophage function and cytokine production. This study found that KODMAC macrophages and vitamin D-deficient macrophages have increased expression and secretion of renin, angiotensin II, ACE, and AT1 receptor and that adhesion, migration, and cytokine release were also increased. Inhibition of ER stress in KODMAC macrophages and vitamin D-deficient macrophages with 4-Phenylbutyric acid (PBA) reduced RAS gene expression and macrophage pro-inflammatory phenotype. Renin 1c gene deletion decreased macrophage adhesion, migration, and cytokine release compared to macrophages with disrupted VDR signaling. Notably, disruption of VDR signaling induced peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) expression in macrophages, and upregulation of renin expression in response to vitamin D deficiency was blunted in PCG1α-deficient macrophages. In conclusion, our findings delineate a mechanism by which impaired VDR signaling induces ER stress to drive PGC1α-dependent expression of renin and RAAS hyperactivation, thereby altering macrophage function and cytokine production. These data implicate RAAS as an essential mediator of VDR-mediated macrophage function and support ongoing investigations of VDR and RAAS modulation as therapeutic approaches in the management of T2DM and its complications.

Venous thromboembolism (VTE) involves the formation of a blood clot, typically in the deep veins of the leg or arm (deep vein thrombosis), which then travels via the circulatory system and ultimately lodges in the lungs, resulting in pulmonary embolism. A number of microRNAs (miRNAs) are well-known regulators of thrombosis and thrombolysis, and mutations in miRNA biogenesis genes, such as DICER1, DROSHA have been implicated in miRNA synthesis and function. We investigated the genetic association between polymorphisms in four miRNA biogenesis genes, DICER1 rs3742330A &gt, G, DROSHA rs10719T &gt, C, RAN rs14035C &gt, T and XPO5 rs11077A &gt, C, and VTE in 503 Koreans: 300 controls and 203 patients. Genotyping was assessed with polymerase chain reaction-restriction fragment length polymorphism assays. We detected associations between polymorphisms in RAN and XPO5 and VTE prevalence (RAN rs14035CC + CT versus TT: p = 0.018, XPO5 rs11077AA + AC versus CC: p &lt, 0.001). Analysis of allele combinations of all four polymorphisms (DICER1, DROSHA, RAN, XPO5) revealed that A-T-T-A was associated with decreased VTE prevalence (p = 0.0002), and A-T-C-C was associated with increased VTE prevalence (p = 0.027). Moreover, in subjects with provoked VTE, the DROSHA rs10719T &gt, C, polymorphism was associated with increased disease prevalence (TT versus TC + CC: p &lt, 0.039). Our study demonstrates that RAN and XPO5 polymorphisms are associated with risk for VTE in Korean subjects.

Background Atypical hemolytic uremic syndrome (aHUS) involves dysregulation of the complement system, but whether this also occurs in thrombotic thrombocytopenic purpura (TTP) remains unclear. Although these conditions are difficult to differentiate clinically, TTP can be distinguished by low (

Diabetes is a chronic inflammatory disease that accelerate cardiovascular disease (CVD). However, the contribution of hyperglycemia to inflammation and CVD risk is unclear. Animal studies have shown that monocytes carry cholesterol to the atherosclerotic plaque. Thus, it is key to determine if hyperglycemia can exert a pro-atherogenic effect in human monocytes in vivo. We performed octreotide euglycemic-hyperglycemic clamps in 21 healthy subjects, 20-45 yo. Monocytes isolated during euglycemia (90 mg/dl) and after 2h of hyperglycemia (300 mg/dl) were evaluated for cholesterol metabolism and monocyte function (adhesion to fibronectin, transwell migration assays). Also, we assessed the effects of hyperglycemia on monocyte cholesterol metabolism and function from 10 healthy controls cultured in euglycemia or high glucose media with or without 2-deoxyglucose (2DG) at 2 and 6 hours. Acute hyperglycemia in vivo increased 37% total monocyte cholesterol content (TC) (p Disclosure R.M. Zhang: None. J. Oh: None. X. Lin: None. P. Stone: None. K.J. Wharton: None. A. Arbelaez: None. C. Bernal-Mizrachi: None. Funding National Heart, Lung, and Blood Institute (R01HL094818-06); National Institute of Neurological Disorders and Stroke (P01NS080675)

Background Recent studies have extensively investigated the role of miRNAs in colorectal cancer (CRC), and several associations have been reported. In addition, single nucleotide polymorphisms (SNPs) in promoter regions of miRNAs have been shown to affect miRNA expression. Therefore, we aimed to analyze the effect of miRNA polymorphisms on CRC susceptibility. Methods We conducted association studies on the relationships between the miRNA polymorphisms miR-130bT > C rs373001, miR-200bT > C rs7549819, and miR-495A > C rs2281611 and CRC with 472 CRC patients and 399 control subjects in Korea. Results Multivariate logistic regressions of the CRC subgroups showed that the miR-495CC genotype associated with rectal cancer (AA+AC vs. CC; adjusted odds ratio (AOR) for CC, 1.592; 95% confidence interval (CI), 1.071–2.368; P = 0.022). The gene-environment combinatorial analysis showed that the combination of miR-495A > C and low plasma folate contributed to an increased risk of rectal cancer (AA+AC vs. CC; AOR for CC, 3.829; 95% CI, 1.577–9.300; P = 0.003). In the survival analysis, miR-200bT > C associated with CRC patient mortality (TT vs TC + CC; adjusted hazard ratio for TC + CC, 0.592; 95% CI, 0.373–0.940; P = 0.026). Conclusion In this study, we found that miR-200b and miR-495 polymorphisms are involved in CRC susceptibility and prognosis. Electronic supplementary material The online version of this article (10.1186/s12885-019-5641-1) contains supplementary material, which is available to authorized users.

Background: Vitamin D deficiency is prevalent in pregnant women and their offspring. Maternal vitamin D deficiency is associated with insulin resistance in children and can induce a proinflammatory macrophage phenotype [1, 2]. Purpose: We hypothesized that maternal vitamin D deficiency induces immune cell reprogramming that promotes adipose insulin resistance in the offspring and is detectable in the newborn period. Methods: We enrolled 32 normal pregnant women prior to delivery of AGA, term infants. Cord blood was obtained and used to determine vitamin D [25(OH)D] levels and qPCR of microRNA levels. Cord blood monocytes were co-cultured with 3T3L1 adipocytes for insulin-stimulated 2-deoxyglucose uptake studies, and the monocyte media and co-cultured adipocytes were analyzed for microRNA expression. 3T3L1 adipocytes were transfected with miR106b mimic and antagonist to confirm the effect of the 2-deoxyglucose results. Results: 83% of the newborn’s venous cord blood showed vitamin D deficiency with 25(OH)D

Table S1. Information of miR-200 and 495 polymorphisms for PCR-RFLP. Table S2. Comparison of genotype frequencies of microRNA polymorphisms between colorectal cancer subtype and control. Table S3. Stratified effects of miR-130bT > C, miR-200bT > C, and miR-495C > A polymorphisms on CRC susceptibility. Table S4. Combinatorial effects of miRNA polymorphisms and environmental factors on CRC risk. (DOCX 26 kb)

Introduction: Poor glycemic control is considered an important contributor to cardiovascular disease in patients with diabetes. Episodic hyperglycemia as a surrogate for glycemic variability promotes monocyte adhesion and increases the prevalence of proinflammatory monocytes within atherosclerotic plaques of patients with diabetes. We previously found that acute hyperglycemia-induced a pro-inflammatory phenotype and promoted the development of foamy monocytes by increasing total cholesterol deposition, cholesterol ester, and free cholesterol content by enhancing oxidized LDL uptake. However, the mechanism by which acute hyperglycemia induces monocyte cholesterol deposition and inflammation remains unknown. Methods: Monocytes isolated from healthy individuals (age range 20–40; n=5) were cultured in low (5mM) or high (16.7mM) glucose conditions with or without a glycolysis inhibitor (2-deoxyglucose, 2DG, 5 mM) or an endoplasmic reticulum stress inhibitor (4-phenylbutyric acid, PBA; 20mM) for 6 hrs. After treatment, cytokine release, oxidized LDL uptake, and metabolic assays using Seahorse Technology were performed. Results: Healthy human monocytes exposed under high glucose conditions showed a pro-atherosclerotic phenotype with higher levels of the pro-inflammatory cytokines, TNFα(median of differences 6.34 pg/ml, p=0.002) and IL1β(12.04 pg/ml, p=0.003), and increased oxidized LDL uptake (5062ug Dil-Ox LDL/mg, p=0.001). Furthermore, hyperglycemia resulted in higher levels of glycolysis (basal glycolysis 12.94 pmol/min, p=0.01; basal proton efflux rate 15.5 pmol/min, p=0.03) and mitochondrial respiration (percentage of respiratory capacity 16pmol/min p=0.04), suggesting a significant alteration in the metabolic programming of these monocytes. Treatment with 2-DG or PBA attenuated the pro-atherosclerotic phenotype induced by hyperglycemia, promoting a reduction of cytokine release, a reduction of oxidized LDL uptake, and near normalization of the glycolic rate and mitochondrial respiration, stabilizing cellular bioenergetics. Conclusions: Altogether, our results suggest that monocyte ER stress in response to acute hyperglycemia promotes a hypermetabolic state characterized by a proinflammatory and proatherogenic monocyte phenotype. Therefore, acute hyperglycemia is a potential mechanism promoting atherosclerosis in patients with type 2 diabetes.

Hyun Chang,1,2,* Jisu Oh,1,3,* Xianglan Zhang,4 Yu Jung Kim,1 Jae Ho Lee,1 Choon-Taek Lee,1 Jin-haeng Chung,5 Jong-Seok Lee1 1Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, 2Division of Medical Oncology, Department of Internal Medicine, International St Mary’s Hospital, College of Medicine, Catholic Kwandong University, Incheon, 3Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea; 4Department of Pathology, Yanbian University Hospital, Yanji, People’s Republic of China; 5Department of Pathology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea *These authors contributed equally to this work Purpose: The aim of this research was to examine the molecular and clinical features that are related with EGFR-tyrosine kinase inhibitor (EGFR-TKI) efficacy in previously treated patients with squamous cell carcinoma of the lung (SCCL). Materials and methods: This retrospective study included 67 SCCL patients with obtainable lung cancer tissue and records on EGFR-TKI treatment response and survival. EGFR protein expression in lung cancer tissue was measured by immunohistochemistry with a specific antibody that recognizes the intracellular domain (ID) of EGFR. PTEN expression in lung cancer tissue was also evaluated with immunohistochemistry. PI3KCA gene amplification was detected by quantitative real-time polymerase chain reaction, and FGFR1 amplification was assessed by fluorescent in situ hybridization. Results: EGFR ID expression (hazard ratio [HR] 0.53, P=0.022) and Eastern Cooperative Oncology Group (ECOG) performance status (PS) (HR 0.43, P=0.022) were significantly related with progression-free survival following EGFR-TKIs treatment. PTEN expression (HR 0.52, P=0.025) was significantly related to overall survival. The group of EGFR-positive or PTEN-positive patients with ECOG PS of 0 or 1 had better clinical outcomes than patients who were EGFR-negative and PTEN-negative or who had poor ECOG PS with longer median progression-free survival (2.1 vs 1.0months, P=0.05) and overall survival (6.2 vs 2.1months, P=0.05). Conclusion: EGFR expression using an ID-specific antibody and PTEN protein expression may be used to identify SCCL patients who might benefit from EGFR-TKI treatment. Keywords: EGFR, tyrosine kinase inhibitor, squamous cell carcinoma, lung, intracellular domain, PTEN

비록 자궁경부암이 갑상선으로의 전이는 매우 드물지만, 자궁경부암의 과거력이 있는 경우, 갑상선부위의 부종이나 촉지되는 결절이 발생하면 반드시 전이성 병변을 의심해봐야 한다. 비록 갑상선으로의 전이는 매우 나쁜 예후를 의미 하지만 고식적 치료로 전신항암요법 및 방사선요법이 환자의 삶의 질 개선에 도움을 줄 수 있다. 드물기는 하지만 갑상선으로의 악성전이 보고가 증가하는 추세로, 이에 대해 어떠한 치료가 가장 효과적일지에 대한 연구가 필요하겠다.

The plasminogen activator inhibitor-1 (PAI-1) is expressed in many cancer cell types and modulates cancer growth, invasion, and angiogenesis. The present study investigated the association between five PAI-1 gene polymorphisms and colorectal cancer (CRC) risk. Five PAI-1 polymorphisms (&minus, 844G&gt, A [rs2227631], &minus, 675 4G&gt, 5G [rs1799889], +43G&gt, A [rs6092], +9785G&gt, A [rs2227694], and +11053T&gt, G [rs7242]) were genotyped using a polymerase chain reaction-restriction fragment length polymorphism assay in 459 CRC cases and 416 controls. Increased CRC risk was more frequently associated with PAI-1 &minus, 675 5G5G polymorphism than with 4G4G (adjusted odds ratio (AOR) = 1.556, 95% confidence interval (CI): 1.012&ndash, 2.391, p = 0.04). In contrast, for the PAI-1 +11053 polymorphism, we found a lower risk of CRC with the GG genotype (AOR = 0.620, 95% CI: 0.413&ndash, 0.932, p = 0.02) than with the TT genotype, as well as for recessive carriers (TT + TG vs. GG, AOR = 0.662, 95% CI: 0.469&ndash, 0.933, p = 0.02). The +43AA genotype was associated with lower overall survival (OS) than the +43GG genotype. Our results suggest that the PAI-1 genotype plays a role in CRC risk. This is the first study to identify an association between five PAI-1 polymorphisms and CRC incidence worldwide.

Folate has essential roles in DNA synthesis, repair and methylation. Folate metabolism-related gene variants may modulate the levels of this vitamin and affect the cancer risk. Thus, whether these polymorphisms play an important role in carcinogenesis, particularly colorectal cancer (CRC) development, has been a subject interest. The present study investigated the association between polymorphisms in the methylenetetrahydrofolate reductase (MTHFR), thymidylate synthase (TS) and the reduced folate carrier 1 (RFC1) genes and CRC risk. Polymorphisms in MTHFR (677C>T and 1298A>C), TS (1494del6 and the TS enhancer region (TSER)) and RFC1 (-43T>C, 80G>A and 696C>T) were characterized using polymerase chain reaction-restriction fragment length polymorphism in 477 CRC cases and 514 controls. Although no polymorphisms were significantly associated with the CRC risk in the overall sample, significant associations between folate metabolism-related polymorphisms and CRC risk were identi- fied in the stratified analyses. The MTHFR 677CT/1298AC and MTHFR 1298AC+CC/TSER 2R3R genotypes in the presence of plasma folate levels ≤4.12 ng/ml were associated with signif- icantly increased CRC risk. In addition, individuals with the MTHFR 677TT/TSER 3R3R or MTHFR 677/TSER 3R3R/TS 1494 0bp6bp+6bp6bp genotypes and diabetes mellitus (DM) were at an increased risk for CRC. Therefore, the data suggest that i) MTHFR polymorphisms combined with low plasma folate levels and ii) polymorphisms in folate metabolism-related genes combined with metabolic syndrome risk factors (hyper- tension and DM) increase the odds of developing CRC.

Cross-sectional studies indicate consistent associations between low 25(OH)D concentration and increased risk of cardiovascular disease (CVD), but results of randomized control trials (RCTs) are mixed. However, the majority of the RCTs do not focus on type 2 diabetics, potentially obscuring the effects of vitamin D in this population. In vitro 1,25(OH)(2)D(3) downregulates macrophage cholesterol deposition, but the in vivo effects are unknown. To explore potential mechanisms of the effects of vitamin D on CVD risk in patients with type 2 diabetes, we isolated monocytes in a subset of 26 patients from our RCT of diabetics with baseline serum 25(OH)D 50% reduction in the vitamin D group with no change in the placebo group. This was mediated through suppression of endoplasmic reticulum stress and scavenger receptor CD36 protein expression. The reduction in monocyte cholesterol uptake was reflected in a 19% decrease in total monocyte cholesterol content. Interestingly, cross-sectional analysis of circulating monocytes from vitamin D-deficient vs. sufficient diabetic patients revealed 8-fold higher cholesteryl ester content, confirming the capacity of these monocytes to uptake and carry cholesterol in the circulation. This study identifies a unique circulating cholesterol pool within monocytes that is modulated by vitamin D and has the potential to contribute to CVD in type 2 diabetes.

Supporting timely data services using fresh data in data-intensive real-time applications, such as e-commerce and transportation management is desirable but challenging, since the workload may vary dynamically. To control the data service delay to be below the specified threshold, we develop a predictive as well as reactive method for database admission control. The predictive method derives the workload bound for admission control in a predictive manner, making no statistical or queuing-theoretic assumptions about workloads. Also, our reactive scheme based on formal feedback control theory continuously adjusts the database load bound to support the delay threshold. By adapting the load bound in a proactive fashion, we attempt to avoid severe overload conditions and excessive delays before they occur. Also, the feedback control scheme enhances the timeliness by compensating for potential prediction errors due to dynamic workloads. Hence, the predictive and reactive methods complement each other, enhancing the robustness of real-time data services as a whole. We implement the integrated approach and several baselines in an open-source database. Compared to the tested open-loop, feedback-only, and statistical prediction + feedback baselines representing the state of the art, our integrated method significantly improves the average/transient delay and real-time data service throughput.

Macrophages are essential in atherosclerosis progression, but regulation of the M1 versus M2 phenotype and their role in cholesterol deposition are unclear. We demonstrate that endoplasmic reticulum (ER) stress is a key regulator of macrophage differentiation and cholesterol deposition. Macrophages from diabetic patients were classically or alternatively stimulated and then exposed to oxidized LDL. Alternative stimulation into M2 macrophages lead to increased foam cell formation by inducing scavenger receptor CD36 and SR-A1 expression. ER stress induced by alternative stimulation was necessary to generate the M2 phenotype through JNK activation and increased PPARγ expression. The absence of CD36 or SR-A1 signaling independently of modified cholesterol uptake decreased ER stress and prevented the M2 differentiation typically induced by alternative stimulation. Moreover, suppression of ER stress shifted differentiated M2 macrophages toward an M1 phenotype and subsequently suppressed foam cell formation by increasing HDL- and apoA-1-induced cholesterol efflux indicating suppression of macrophage ER stress as a potential therapy for atherosclerosis.

It is essential to process real-time data service requests such as stock quotes and trade transactions in a timely manner using fresh data, which represent the current real-world phenomena such as the stock market status. Users may simply leave when the database service delay is excessive. Also, temporally inconsistent data may give an outdated view of the real-world status. However, supporting the desired timeliness and freshness is challenging due to dynamic workloads. To address the problem, we present new approaches for 1) database backlog estimation, 2) fine-grained closed-loop admission control based on the backlog model, and 3) incoming load smoothing. Our backlog estimation and control-theoretic approaches aim to support the desired service delay bound without degrading the data freshness, critical for real-time data services. Specifically, we design, implement, and evaluate two feedback controllers based on linear control theory and fuzzy logic control theory, to meet the desired service delay. Workload smoothing, under overload, helps the database admit and process more transactions in a timely fashion by probabilistically reducing the burstiness of incoming data service requests. In terms of the data service delay and throughput, our closed-loop admission control and probabilistic load smoothing schemes considerably outperform several baselines in the experiments undertaken in a stock trading database testbed.

Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression and metastasis. Moreover, recent studies have reported that a number of 3′-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967] and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3′-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3′-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention.

MicroRNAs play an important role in cancer initiation and development. The aim of this study was to investigate whether polymorphisms in miRNA machinery genes are associated with the development of colorectal cancer (CRC). RAN rs14035 CT heterozygotes and T allele carriers (CT + TT) genotypes had lower risk of CRC, while the DICER1 rs3742330, DROSHA rs10719, and XPO5 rs11077 polymorphisms were not associated with CRC in the full study sample. Specifically, male RAN rs14035 CT heterozygotes and XPO5 rs11077 AA genotype (CT/AA) carriers experienced reduced CRC susceptibility (both colon and rectal). Subgroup analysis demonstrated that the combined RAN rs14035 CT + TT genotype was associated with rectal cancer, but not colon cancer. In addition, the DICER1 rs3742330 AG genotype was associated with a significantly increased risk of colon cancer. Stratified analysis revealed the RAN rs14035 combined CT+TT genotype was associated with decreased CRC risk in male patients without diabetes mellitus (DM) and in patients with rectal cancer. In addition, we found the RAN rs14035 CC genotype was related to a decreased risk of CRC with respect to tumor size and metabolism of homocysteine and folate. Furthermore, patients diagnosed with hypertension or DM who carried the DROSHA rs10719 CC genotype showed increased CRC risk, while the XPO5 rs11077 AC+CC genotype led to increased CRC risk in patients with hypertension only. Our results indicate variations in RAN rs14035, DICER1 rs3742330, XPO5 rs11077, and DROSHA rs10719 of Korean patients are significantly associated with their risk of CRC.

Background Polymorphisms in angiogenesis-related genes and metabolic syndrome (MetS) risk factors play important roles in cancer development. Moreover, recent studies have reported associations between a number of 3′-UTR polymorphisms and a variety of cancers. The aim of this study was to investigate the associations of three VEGF 3′-UTR polymorphisms (1451C > T [rs3025040], 1612G > A [rs10434], and 1725G > A [rs3025053]) and MetS with colorectal cancer (CRC) susceptibility in Koreans. Methods A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of VEGF polymorphisms was performed by TaqMan allelic discrimination assays. Cancer risks of genetic variations and gene-environment interactions were assessed by adjusted odds ratios (AORs) and 95% confidence intervals (CIs) of multivariate logistic regression analyses. Results VEGF 1451C > T was significantly associated with rectal cancer risk (Dominant model; AOR =1.58; 95% CI = 1.09 - 2.28; p = 0.015) whereas VEGF 1725G > A correlated with MetS risk (Dominant model; AOR =1.61; 95% CI =1.06 - 2.46; p = 0.026). Of the gene-environment combined effects, the interaction of VEGF 1451C > T and MetS contributed to increased rectal cancer risk (AOR = 3.15; 95% CI = 1.74 - 5.70; p A and MetS was involved with elevated colon cancer risk (AOR = 2.68; 95% CI = 1.30 - 1.55; p =0.008). Conclusions Our results implicate that VEGF 1451C > T and 1725G > A may predispose to CRC susceptibility and the genetic contributions may be varied with the presence of MetS. Electronic supplementary material The online version of this article (doi:10.1186/1471-2407-14-881) contains supplementary material, which is available to authorized users.

We present a 30-year-old male patient who was initially diagnosed as minimal change nephrotic syndrome, 5 years later, the patient developed a localized form of idiopathic retroperitoneal fibrosis (IRF). An elevated ESR and concomitant nephrotic syndrome in the patient suggested the immunologic nature of IRF, IRF has been reported in association with collagen diseases and rarely with proliferative and nonproliferative glomerulopathies. To our knowledge, the association between minimal change lesion (MC) and IRF has not been reported. Furthermore, the fact that IRF presented itself as an abdominal mass and lacked systemic symptoms was also unusual.

The microRNA (miR)-34 family is a direct transcriptional target of tumor-suppressor TP53 and loss of miR-34 function may impair TP53-mediated cell cycle arrest and apoptosis. In the present study, we investigated whether the single nucleotide polymorphisms (SNPs) rs4938723 (T>C) in the promoter region of miR-34b/c and Arg72Pro (G>C) in codon 72 of TP53 are independently or complementarily associated with the risks and clinical outcomes of colorectal cancer (CRC) and whether the combined effect of these SNPs and metabolic risk factors are related to CRC. We evaluated the SNPs in 545 CRC patients and 428 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequence analysis. We found that the GC and GC/CC genotypes of TP53 Arg72Pro were associated with decreased risk of CRC (adjusted OR = 0.727 for GC; OR = 0.735 for GC/CC). The combined genotypes of TT-GC and CC-GG were significantly associated with reduced CRC risk (adjusted OR = 0.628 for TT-GC; OR = 0.381 for CC-GG, respectively). The SNP rs4938723 and diabetes mellitus (DM) together were associated with an increased CRC risk, but the SNP TP53 Arg72Pro CC with DM showed a protective effect against CRC. These findings indicate that rs4938723 in the promoter region of pri-miR-34b/c and the SNP in TP53 codon 72 were related to decreased risk of CRC in the population studied and those metabolic diseases and genetic variants influence each other with regard to CRC susceptibility.

Cardiovascular disease (CVD) is the leading cause of mortality in patients with type 2 diabetes mellitus (T2DM). Vitamin D deficiency is not only more prevalent in diabetics but also doubles the risk of developing CVD. However, it is unknown whether 25-hydroxy vitamin D [25(OH)D3] replacement slows monocyte adhesion and migration, critical mechanisms involved in atherosclerosis progression. In this study, monocytes from vitamin D-deficient diabetic patients were cultured either in the patient's serum or in vitamin D-deficient media with or without 25(OH)D3 treatment. Adding 25(OH)D3 to monocytes cultured in vitamin D-deficient serum or media decreased monocyte adhesion to fibronectin and migration stimulated by monocyte chemotactic protein 1 (MCP-1). Accordingly, 25(OH)D3 decreased adhesion marker β1- and β2-integrin expression and migration receptor chemokine (C-C motif) receptor 2 (CCR2) expression. 25(OH)D3 treatment downregulated monocyte endoplasmic reticulum (ER) stress and scavenger receptor class A, type 1 (SR-A1) expression. The absence of SR-A1 prevented the increased macrophage adhesion and migration induced by vitamin D deficiency. Moreover, the absence of SR-A1 prevented the induction of adhesion and migration and expression of their associated membrane receptors by Thapsigargin, an ER stress inducer. These results identify cellular activation of monocyte/macrophage vitamin D signaling through 25(OH)D3 as a potential mechanism that could modulate adhesion and migration in diabetic subjects. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.

Cardiovascular disease is the leading cause of morbidity/mortality in patients with type 2 diabetes mellitus (T2DM), but there is a lack of knowledge about the mechanism(s) of increased atherosclerosis in these patients. In patients with T2DM, the prevalence of 25-hydroxy vitamin D (25(OH)D) deficiency is almost twice that for nondiabetics and doubles the relative risk of developing cardiovascular disease compared with diabetic patients with normal 25(OH)D. We tested the hypothesis that monocytes from vitamin D-deficient subjects will have a proatherogenic phenotype compared with vitamin D-sufficient subjects in 43 patients with T2DM. Serum 25(OH)D level inversely correlated with monocyte adhesion to endothelial cells even after adjustment for demographic and comorbidity characteristics. Vitamin D-sufficient patients (≥30 ng/ml 25(OH)D) had lower monocyte endoplasmic reticulum (ER) stress, a predominance of M1 over M2 macrophage membrane receptors, and decreased mRNA expression of monocyte adhesion molecules PSGL-1, β(1)-integrin, and β(2)-integrin compared with patients with 25(OH)D levels of30 ng/ml. In vitamin D-deficient macrophages, activation of ER stress increased adhesion and adhesion molecule expression and induced an M2-predominant phenotype. Moreover, adding 1,25(OH)(2)D(3) to vitamin D-deficient macrophages shifted their phenotype toward an M1-predominant phenotype with suppressed adhesion. Conversely, deletion of the vitamin D receptor in macrophages from diabetic patients activated ER stress, accelerated adhesion, and increased adhesion molecule expression. The absence of ER stress protein CCAAT enhancer-binding protein homologous protein suppressed monocyte adhesion, adhesion molecule expression, and the M2-predominant phenotype induced by vitamin D deficiency. Thus, vitamin D is a natural ER stress reliever that induced an antiatherogenic monocyte/macrophage phenotype.

Multiple epidemiological studies link vitamin D deficiency to increased cardiovascular disease (CVD), but causality and possible mechanisms underlying these associations are not established. To clarify the role of vitamin D-deficiency in CVD in vivo, we generated mouse models of diet-induced vitamin D deficiency in two backgrounds (LDL receptor- and ApoE-null mice) that resemble humans with diet-induced hypertension and atherosclerosis. Mice were fed vitamin D-deficient or -sufficient chow for 6 weeks and then switched to high fat (HF) vitamin D-deficient or -sufficient diet for 8-10 weeks. Mice with diet-induced vitamin D deficiency showed increased systolic and diastolic blood pressure, high plasma renin, and decreased urinary sodium excretion. Hypertension was reversed and renin was suppressed by returning chow-fed vitamin D-deficient mice to vitamin D-sufficient chow diet for 6 weeks. On a HF diet, vitamin D-deficient mice had ~2-fold greater atherosclerosis in the aortic arch and ~2-8-fold greater atherosclerosis in the thoracic and abdominal aorta compared to vitamin D-sufficient mice. In the aortic root, HF-fed vitamin D-deficient mice had increased macrophage infiltration with increased fat accumulation and endoplasmic reticulum (ER) stress activation, but a lower prevalence of the M1 macrophage phenotype within atherosclerotic plaques. Similarly, peritoneal macrophages from vitamin D-deficient mice displayed an M2-predominant phenotype with increased foam cell formation and ER stress. Treatment of vitamin D-deficient mice with the ER stress reliever PBA during HF feeding suppressed atherosclerosis, decreased peritoneal macrophage foam cell formation, and downregulated ER stress proteins without changing blood pressure. Thus, we suggest that vitamin D deficiency activates both the renin angiotensin system and macrophage ER stress to contribute to the development of hypertension and accelerated atherosclerosis, highlighting vitamin D replacement as a potential therapy to reduce blood pressure and atherosclerosis.

Reduced monocyte infiltration into the vessel wall and increased macrophage cholesterol efflux are critical components in atherosclerotic plaque regression. During inflammation, monocyte chemotactic protein 1 (MCP-1) signaling activation and cholesterol deposition in macrophages induce endoplasmic reticulum (ER) stress, which promotes an increased inflammatory response. Increased macrophage ER stress shifts macrophages into an M2 macrophage phenotype with increased cholesterol uptake and deposition. In type 2 diabetes, a population with elevated baseline risk of cardiovascular disease (CVD), vitamin D deficiency doubles that risk. We have found that 1,25-dihydroxy vitamin D [1,25(OH)2D] prevents foam cell formation during macrophage differentiation by suppressing ER stress. However, it is unknown whether suppression of ER stress by 1,25(OH)2D decreases monocyte infiltration and reverses atherogenic cholesterol metabolism in previously differentiated, vitamin D-deplete macrophages. We collected peripheral monocytes from type 2 diabetic patients and differentiated them into macrophages under vitamin D-deplete or 1,25(OH)2D-supplemented conditions. 1,25(OH)2D supplementation suppressed macrophage migration in response to MCP-1 and mRNA expression of chemokine (C-C motif) receptor 2 (CCR2), the MCP-1 receptor, compared to vitamin D-deplete cells. Furthermore, inhibition of ER stress with phenyl butyric acid resulted in similar effects even in vitamin D-deplete cells, while induction of ER stress with Thapsigargin under 1,25(OH)2D-supplemented conditions increased macrophage migration and CCR2 expression, suggesting that the effects of vitamin D on migration are mediated through ER stress suppression. To determine whether the detrimental pattern of macrophage cholesterol metabolism in vitamin D depletion is reversible, we assessed cholesterol uptake in macrophages differentiated under vitamin D-deplete conditions as described above, then supplemented with 1,25(OH)2D or maintained in vitamin D-deplete conditions. Cholesterol uptake was decreased in 1,25(OH)2D-supplemented compared to vitamin D-deplete cells, suggesting slowed cholesterol deposition with active vitamin D. 1,25(OH)2D supplementation also suppressed cholesteryl ester formation and enhanced cholesterol efflux in M2 macrophages compared to vitamin D-deplete cells, suggesting facilitation of cholesterol egress in the presence of 1,25(OH)2D. We thus provide further evidence that active vitamin D is an ER stress reliever that may have a role in atherosclerotic plaque regression. This article is part of a Special Issue entitled 'Vitamin D Workshop'.

Although it was thought that platelets did not play a significant role in the pathogenesis of venous thromboembolism (VTE), several studies demonstrated that a marked activation of platelets occurs in patients with VTE. We carried out a case–control study to investigate the effect of the T744C P2RY12 polymorphism on the risk of VTE in the Korean population. We enrolled 154 consecutive patients with VTE and 415 healthy controls. Genotype frequencies for patients with TT, TC, and CC were 71.4%, 24.7%, and 3.9% and in the controls, 68.2%, 30.1%, and 1.7%, respectively. T744C P2RY12 polymorphism did not significantly affect the risk of VTE. Our study shows that T744C P2RY12 polymorphism did not significantly affect the risk of VTE in the Korean population.

Background— Cardiovascular disease is the leading cause of death among those with diabetes mellitus. Vitamin D deficiency is associated with an increased risk of cardiovascular disease in this population. To determine the mechanism by which vitamin D deficiency mediates accelerated cardiovascular disease in patients with diabetes mellitus, we investigated the effects of active vitamin D on macrophage cholesterol deposition. Methods and Results— We obtained macrophages from 76 obese, diabetic, hypertensive patients with vitamin D deficiency (25-hydroxyvitamin D 3 [1,25(OH) 2 D 3 ] –supplemented media and exposed to modified low-density lipoprotein cholesterol. 1,25(OH) 2 D 3 suppressed foam cell formation by reducing acetylated or oxidized low-density lipoprotein cholesterol uptake in diabetic subjects only. Conversely, deletion of the vitamin D receptor in macrophages from diabetic patients accelerated foam cell formation induced by modified LDL. 1,25(OH) 2 D 3 downregulation of c-Jun N-terminal kinase activation reduced peroxisome proliferated–activated receptor-γ expression, suppressed CD36 expression, and prevented oxidized low-density lipoprotein–derived cholesterol uptake. In addition, 1,25(OH) 2 D 3 suppression of macrophage endoplasmic reticulum stress improved insulin signaling, downregulated SR-A1 expression, and prevented oxidized and acetylated low-density lipoprotein–derived cholesterol uptake. Conclusion— These results identify reduced vitamin D receptor signaling as a potential mechanism underlying increased foam cell formation and accelerated cardiovascular disease in diabetic subjects.

Real-time data services can benefit data-intensive real-time applications, e.g., e-commerce, via timely transaction processing using fresh data, e.g., the current stock prices. To enhance the real-time data service quality, we present several novel techniques for (1) database backlog estimation, (2) fine-grained closed-loop admission control based on the backlog model, and (3) hint-based incoming load smoothing. Our backlog estimation and feedback control aim to support the desired service delay bound without degrading the data freshness critical for real-time data services. Workload smoothing, under overload, help the database admit and process more transactions in a timely manner by probabilistically reducing the burstiness of incoming data service requests. In terms of the data service delay and throughput, our feedback-based admission control and probabilistic load smoothing considerably outperform the baselines, which represent the current state of the art, in the experiments performed in a stock trading database testbed.

It is challenging to manage the performance of real-time databases (RTDBs) that are often used in data-intensive real-time applications such as agile manufacturing and target tracking. Feedback control has recently been considered a promising approach to enabling reliable real-time data service. However, most existing work on feedback control of RTDB performance is not based on a RTDB-specific control model, which is critical for closed-loop system design. To address this problem, we design a novel RTDB model that can capture RTDB dynamics by modeling the relation between the total arrival rate (sum of the transaction arrival rate and restart rate) and utilization via a difference equation. Based on the model, we design and tune a utilization controller to compute the total arrival rate adjustment needed to support the desired average/transient utilization. We also design a QoS management scheme and admission control technique that can judiciously adapt the transaction QoS and arrival rate in a RTDB, if necessary, to support the desired utilization, while enhancing the success ratio. In a simulation study, we show that our approach can support the desired average/transient utilization for a range of transaction arrival rates under severe data contention, while considerably improving the success ratio compared to the tested baselines