IRAK regulates macrophage foam cell formation by modulating genes involved in cholesterol uptake and efflux.

Interleukin-1 receptor-associated kinase-1 (IRAK1) is linked to the pathogenesis of atherosclerosis; however, its role in macrophage foam cell formation is not known. Therefore, the present study investigated the role of IRAK1 in lipid uptake, biosynthesis, and efflux in THP-1 derived macrophages and human monocyte-derived macrophages (HMDMs). Ox-LDL (40 µg/mL, 15 minutes-48 hours) treatment induced time-dependent increase in IRAK1, IRAK4, and Stat1 activation in THP-1 derived macrophages. IRAK1/4 inhibitor (INH) or IRAK1 siRNA significantly attenuated cholesterol accumulation, DiI-Ox-LDL binding, and uptake while cholesterol efflux to apoAI and HDL was enhanced in THP-1 derived macrophages and HMDMs. Ox-LDL treatment significantly increased the mRNA expression of CD36, LOX-1, SR-A, ABCA1, ABCG1, Caveolin-1, CYP27A1 while that of SR-BI was decreased. IRAK1/4 inhibition or IRAK1 knockdown, however, attenuated Ox-LDL-induced CD36 expression; augmented ABCA1 and ABCG1 expression while expression of others was unaffected in THP-1 derived macrophages and HMDMs. Moreover, IRAK1/4 inhibition had no significant effect on genes involved in lipid biosynthesis. In IRAK1/4 INH pre-treated THP-1 derived macrophages Ox-LDL-induced Stat1 phosphorylation and its binding to CD36 promoter was significantly attenuated while LXRα expression and its binding to the ABCA1/ABCG1 locus, NFATc2 activation and its binding to ABCA1 locus was enhanced. The present study thus demonstrates that IRAK regulates lipid accumulation by modulating CD36-mediated uptake and ABCA1-, ABCG1-dependent cholesterol efflux. Therefore, IRAK1 can be a potential target for preventing macrophage foam cell formation.

PKCδ-IRAK1 axis regulates oxidized LDL-induced IL-1ß production in monocytes.

This study examined the role of interleukin (IL)-1 receptor-associated kinase (IRAK) and protein kinase C (PKC) in oxidized LDL (Ox-LDL)-induced monocyte IL-1ß production. In THP1 cells, Ox-LDL induced time-dependent secretory IL-1ß and IRAK1 activity; IRAK4, IRAK3, and CD36 protein expression; PKCδ-JNK1 phosphorylation; and AP-1 activation. IRAK1/4 siRNA and inhibitor (INH)-attenuated Ox-LDL induced secreted IL-1ß and pro-IL-1ß mRNA and pro-IL-1ß and mature IL-1ß protein expression, respectively. Diphenyleneiodonium chloride (NADPH oxidase INH) and N-acetylcysteine (free radical scavenger) attenuated Ox-LDL-induced reactive oxygen species generation, caspase-1 activity, and pro-IL-1ß and mature IL-1ß expression. Ox-LDL-induced secretory IL-1ß production was abrogated in the presence of JNK INH II, Tanshinone IIa, Ro-31-8220, Go6976, Rottlerin, and PKCδ siRNA. PKCδ siRNA attenuated the Ox-LDL-induced increase in IRAK1 kinase activity, JNK1 phosphorylation, and AP-1 activation. In THP1 macrophages, CD36, toll-like receptor (TLR)2, TLR4, TLR6, and PKCδ siRNA prevented Ox-LDL-induced PKCδ and IRAK1 activation and IL-1ß production. Enhanced Ox-LDL and IL-1ß in systemic inflammatory response syndrome (SIRS) patient plasma demonstrated positive correlation with each other and with disease severity scores. Ox-LDL-containing plasma induced PKCδ and IRAK1 phosphorylation and IL-1ß production in a CD36-, TLR2-, TLR4-, and TLR6-dependent manner in primary human monocytes. Results suggest involvement of CD36, TLR2, TLR4, TLR6, and the PKCδ-IRAK1-JNK1-AP-1 axis in Ox-LDL-induced IL-1ß production.

IL-1R-associated kinase-1 mediates protein kinase Cδ-induced IL-1ß production in monocytes.

The role of IL-1R-associated kinase (IRAK)1 and its interaction with protein kinase C (PKC)δ in monocytes to regulate IL-1ß production has not been reported so far. The present study thus investigates such mechanisms in the THP1 cell line and human monocytes. PMA treatment to THP1 cells induced CD11b, TLR2, TLR4, CD36, IRAK1, IRAK3, and IRAK4 expression, IRAK1 kinase activity, PKCδ and JNK phosphorylation, AP-1 and NF-κB activation, and secretory IL-1ß production. Moreover, PMA-induced IL-1ß production was significantly reduced in the presence of TLR2, TLR4, and CD11b Abs. Rottlerin, a PKCδ-specific inhibitor, significantly reduced PMA-induced IL-1ß production as well as CD11b, TLR2 expression, and IRAK1-JNK activation. In PKCδ wild-type overexpressing THP1 cells, IRAK1 kinase activity and IL-1ß production were significantly augmented, whereas recombinant inactive PKCδ and PKCδ small interfering RNA significantly inhibited basal and PMA-induced IRAK1 activation and IL-1ß production. Endogenous PKCδ-IRAK1 interaction was observed in quiescent cells, and this interaction was regulated by PMA. IRAK1/4 inhibitors, their small interfering RNAs, and JNK inhibitor also attenuated PMA-induced IL-1ß production. NF-κB activation inhibitor and SN50 peptide inhibitor, however, failed to affect PMA-induced IL-1ß production. A similar role of IRAK1 in IL-1ß production and its regulation by PKCδ was evident in the primary human monocytes, thus signifying the importance of our finding. To our knowledge, the results obtained demonstrate for the first time that IRAK1 and PKCδ functionally interact to regulate IL-1ß production in monocytic cells. A novel mechanism of IL-1ß production that involves TLR2, CD11b, and the PKCδ/IRAK1/JNK/AP-1 axis is thus being proposed.

Multi-strategy Gaussian Harris hawks optimization for fatigue life of tapered roller bearings.

Bearing is one of the most fundamental components of rotary machinery, and its fatigue life is a crucial factor in designing. The design optimization of tapered roller bearing (TRB) is a complex design problem because various arrays of designing parameters and functional requirements should be fulfilled. Since there are many design variables and nonlinear constraints, presenting an optimal design of TRBs poses some challenges for metaheuristic algorithms. The Harris hawks optimization (HHO) algorithm is a robust nature-inspired method with unique exploitation and exploration phases due to its time-varying structure. However, this metaheuristic algorithm may still converge to local optima for more challenging problems such as the design of TRBs. Therefore, this study aims to improve the accuracy and efficiency of the shortcomings of this algorithm. The performance of the proposed algorithm is first evaluated for the TRB optimization problem. The TRB optimization design has nine design variables and 26 constraints because of geometrical dimensions and strength conditions. The productivity of the proposed method is compared with diverse metaheuristic algorithms in the literature. The results demonstrate the significant development of dynamic load capacity in comparison to the standard value. Furthermore, the enhanced version of the HHO algorithm presented in this study is benchmarked with various well-known engineering problems. For supplementary materials regarding algorithms in this research, readers can refer to https://aliasgharheidari.com.

Development of one dimensional geomechanical model for a tight gas reservoir.

Estimating rock-mechanical, petrophysical properties and pre-production stress state is essential for effective reservoir planning, development, and optimal exploitation. This paper attempts to construct a comprehensive one-dimensional mechanical earth model (1D MEM) of the Mandapeta gas reservoir of Krishna Godavari (KG) basin, India. The methodology comprises a detailed stepwise process from processing and analysis of raw log data, calibration of log-derived dynamic properties with static ones using regression models developed from tested core samples, and final rock mechanical property estimation. Pore pressure profiles have been estimated and calibrated with the Repeat formation tester (RFT) data for every thirty-five wells. Overburden and horizontal stresses have also been evaluated and calibrated using data from the Leak-off Tests (LOT) or Extended Leak-off Tests (XLOT). A menu-driven program is developed using PYTHON code for visualization and on-time revision of 1D MEM. The resulting comprehensive 1D MEM predicts and establishes the rock-mechanical properties, pore pressure, and in-situ stress values of the basin. Besides its use in planning future wells, development of the field, and yielding insight into the various well challenges, it can also be used to develop a 3D MEM of the reservoir.

A Wnt5a-Cdc42 axis controls aging and rejuvenation of hair-follicle stem cells.

Normal hair growth occurs in cycles, comprising growth (anagen), cessation (catagen) and rest (telogen). Upon aging, the initiation of anagen is significantly delayed, which results in impaired hair regeneration. Hair regeneration is driven by hair follicle stem cells (HFSCs). We show here that aged HFSCs present with a decrease in canonical Wnt signaling and a shift towards non-canonical Wnt5a driven signaling which antagonizes canonical Wnt signaling. Elevated expression of Wnt5a in HFSCs upon aging results in elevated activity of the small RhoGTPase Cdc42 as well as a change in the spatial distribution of Cdc42 within HFSCs. Treatment of aged HFSC with a specific pharmacological inhibitor of Cdc42 activity termed CASIN to suppress the aging-associated elevated activity of Cdc42 restored canonical Wnt signaling in aged HFSCs. Treatment of aged mice in vivo with CASIN induced anagen onset and increased the percentage of anagen skin areas. Aging-associated functional deficits of HFSCs are at least in part intrinsic to HFSCs and can be restored by rational pharmacological approaches.

Models to study atherosclerosis: a mechanistic insight.

The recent failure of candidate drugs like cholesterol ester transfer protein (CETP) and acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors calls for a revised approach for screening anti-atherosclerotic drugs and development of new models of atherosclerosis. For this it is important to understand the mechanism of the disease in a particular model. Models simultaneously showing hyperlipidemia, inflammation and associated complications of diabetes and hypertension will serve the purpose better as they mimic the actual clinical condition. Besides this, analyzing candidate molecules in vivo, in vitro and at various levels of atherosclerosis progression is important. Models based on various cells and process involved in atherosclerosis should be used for screening candidate molecules. The challenge lies in bridging the gap between genetically friendly small animal and human-like bigger animal models. Sequencing of the mouse and human genome, development of a single nucleotide polymorphism (SNP) database and in silico quantitative trait loci (QTL) linkage analysis may enhance the understanding of atherosclerosis and help develop new therapeutic targets.

Correction to: The IRAK-ERK-p67phox-Nox-2 axis mediates TLR4, 2-induced ROS production for IL-1ß transcription and processing in monocytes.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Factors affecting the outcome of neuroendoscopy in patients with tuberculous meningitis hydrocephalus: a preliminary study.

BACKGROUND: In recent years, ETV has been found to be effective in patients with TBMH; however, its precise selection criteria are yet to be established. We carried out this study to identify the factors affecting the outcome of ETV in TBMH. METHODS: Fourteen patients with TBMH (11 male patients and 3 female patients; mean age, 15.7 years; range, 9 months to 40 years) formed the study group. Various preoperative (clinical grade, ventricular morphology, basal exudates, and CNS tuberculoma) and perioperative (ependymal tubercles, third ventricular floor anatomy, exudates, and adhesions) factors were studied with regard to the result of ETV. Endoscopic third ventriculostomy could be performed on 13 patients; however, an unidentifiable third ventricular floor anatomy precluded ETV in the remaining patient. Endoscopic third ventriculostomy was assigned as "failed" if the patient needed shunt, required EVD, or died in the postoperative period. The average follow-up period for the patients was 5 months. RESULTS: Endoscopic third ventriculostomy was successful in 9 of the 14 (64.2%) patients subjected to neuroendoscopy. Statistical analysis did not show any significant association of ventricular morphology (P = .109), basal enhancement on CT (P = .169), CNS tuberculoma (P = .169), and clinical grade (P = .057) with the result of ETV, probably because of the small number of cases. However, patients with severe hyponatremia, extra-CNS tuberculosis, an unidentifiable third ventricular floor anatomy, and adhesions in the prepontine cistern had a failed ETV. Patients with tuberculoma in the brain had a successful ETV. CONCLUSIONS: Endoscopic third ventriculostomy is likely to fail in the presence of advanced clinical grade, extra-CNS tuberculosis, dense adhesions in prepontine cisterns, and an unidentifiable third ventricular floor anatomy. Tuberculoma in the brain in cases of TBMH may be associated with a successful ETV.

Limitations and challenges of genetic barcode quantification.

Genetic barcodes are increasingly used to track individual cells and to quantitatively assess their clonal contributions over time. Although barcode quantification relies entirely on counting sequencing reads, detailed studies about the method's accuracy are still limited. We report on a systematic investigation of the relation between barcode abundance and resulting read counts after amplification and sequencing using cell-mixtures that contain barcodes with known frequencies ("miniBulks"). We evaluated the influence of protocol modifications to identify potential sources of error and elucidate possible limitations of the quantification approach. Based on these findings we designed an advanced barcode construct (BC32) to improved barcode calling and quantification, and to ensure a sensitive detection of even highly diluted barcodes. Our results emphasize the importance of using curated barcode libraries to obtain interpretable quantitative data and underline the need for rigorous analyses of any utilized barcode library in terms of reliability and reproducibility.

The IRAK-ERK-p67phox-Nox-2 axis mediates TLR4, 2-induced ROS production for IL-1ß transcription and processing in monocytes.

In monocytic cells, Toll-like receptor 4 (TLR4)- and TLR2-induced reactive oxygen species (ROS) cause oxidative stress and inflammatory response; however, the mechanism is not well understood. The present study investigated the role of interleukin-1 receptor-associated kinase (IRAK), extracellular signal-regulated kinase (ERK), p67phox and Nox-2 in TLR4- and TLR2-induced ROS generation during interleukin-1 beta (IL-1ß) transcription, processing, and secretion. An IRAK1/4 inhibitor, U0126, PD98059, an NADPH oxidase inhibitor (diphenyleneiodonium (DPI)), and a free radical scavenger (N-acetyl cysteine (NAC))-attenuated TLR4 (lipopolysaccharide (LPS))- and TLR2 (Pam3csk4)-induced ROS generation and IL-1ß production in THP-1 and primary human monocytes. An IRAK1/4 inhibitor and siRNA-attenuated LPS- and Pam3csk4-induced ERK-IRAK1 association and ERK phosphorylation and activity. LPS and Pam3csk4 also induced IRAK1/4-, ERK- and ROS-dependent activation of activator protein-1 (AP-1), IL-1ß transcription, and IL-1ß processing because significant inhibition in AP-1 activity, IL-1ß transcription, Pro- and mature IL-ß expression, and caspase-1 activity was observed with PD98059, U0126, DPI, NAC, an IRAK1/4 inhibitor, tanshinone IIa, and IRAK1 siRNA treatment. IRAK-dependent ERK-p67phox interaction, p67phox translocation, and p67phox-Nox-2 interaction were observed. Nox-2 siRNA significantly reduced secreted IL-1ß, IL-1ß transcript, pro- and mature IL-1ß expression, and caspase-1 activity indicating a role for Nox-2 in LPS- and Pam3csk4-induced IL-1ß production, transcription, and processing. In the present study, we demonstrate that the TLR4- and TLR2-induced IRAK-ERK pathway cross-talks with p67phox-Nox-2 for ROS generation, thus regulating IL-1ß transcription and processing in monocytic cells.

HIV-1 infection in early seroconversion stage missed by rapid or ELISA tests--two case reports.

Two cases of HIV-1 infection demonstrating lack of sensitivity of rapid and ELISA screening tests are being reported. The first case was that of a 23 years old female whose recent infection was picked up by ELISA (Tetra ELISA) test but missed by two rapid tests (Comb AIDS and HIV Tridot). The 2nd case presumably too in early seroconversion phase, was that of a 39 years old male. In this case ELISA test failed to diagnose the infection while the two rapid tests were found to be strongly positive.

Hyalohyphomycosis of maxillary antrum.

Fungal infection of the paranasal sinuses is an increasingly recognized entity, both in normal and immunocompromised individuals. The recent increase in mycotic nasal and paranasal infections is due to both improved diagnostic research and an increase in the conditions that favor fungal infection. Although fungal infections of the paranasal sinus are uncommon, 3-5% of incidence is reported. Aspergillus, Candida, and Mucor species are the most common causative agents of fungal sinusitis, but infection with lesser known species have been reported across the world infrequently. This article reviews and presents a case report of chronic fungal sinusitis in an immunocompetent adult male infected with two species of Hyalohyphomycosis group namely, Paecilomyces and Scopulariopsis which are opportunistic soil saprophytes, uncommon to humans.

Sterilization of extracted human teeth: A comparative analysis.

BACKGROUND: Extracted human teeth are regularly used for practice and educational purposes in dental institutions at undergraduate and postgraduate levels. Different materials and methods are used for sterilizing extracted teeth to avoid infection from them. AIMS: The present study was done to determine the efficacy of some frequently used methods for disinfection/sterilization of extracted human teeth. MATERIALS AND METHODS: A total of 120 intact, non-carious teeth extracted due to periodontal or orthodontic purpose were divided randomly into 8 groups consisting of 15 teeth in each group. Agents used for sterilization included 10% formalin, 0.1% thymol in distilled water, 5.25% sodium hypochlorite, 2% glutaraldehyde, 3% hydrogen peroxide, boiled in water (100 °C), autoclave (121 °C, 15 lbs psi), normal saline. Samples were collected with the help of inoculating loop and then streaked over the surface of Mc-Conkey agar medium and Blood agar medium. The media were then incubated at 37 °C for 24 h. No visible growth in the culture medium was considered as the method of effective sterilization. RESULTS: 10% formalin, autoclaving, 5.25% sodium hypochlorite could be efficiently used for sterilization and disinfection of extracted human teeth. CONCLUSION: Extracted teeth should be handled with extreme care as these are potential source of infection and need to be disinfected before they are used in the laboratories.

A time course study on prothrombotic parameters and their modulation by anti-platelet drugs in hyperlipidemic hamsters.

The present study was undertaken to assess the chronology of major pathological events associated with high cholesterol (HC) diet and their modulation by anti-platelet drugs. Male Golden Syrian hamsters were fed HC diet up to 90 days. Plasma lipid, glucose and coagulation parameters (commercial kits), platelet activation (whole blood aggregation and static adhesion), endothelial dysfunction (aortic ring vasoreactivity), splenocyte TNF-α, IFN-γ and iNOS mRNA transcripts (RT-PCR), and ferric chloride (time to occlusion) induced thrombosis were monitored at 15, 30, 60, and 90 days after HC feeding and compared with normolipidemic hamsters. A significant increase in plasma lipid levels was observed at 15 days of HC feeding, but other parameters remain unaltered. Enhanced ADP, collagen, and thrombin-induced platelet aggregation, splenocyte TNF-α expression along with endothelial dysfunction were observed from 30 to 90 days of HC feeding. Platelet adhesion on collagen-/fibrinogen-coated surface and IFN-γ expression were augmented only after 60 days, while enhanced iNOS expression, reduction in thrombin time, and potentiation of ferric chloride-induced thrombosis was observed only at 90 days of HC feeding. Thus, pathological changes induced by HC diet depend on the duration and extent of hyperlipidemia. Moreover, hamsters treated with anti-platelet drugs aspirin (5 mg/kg) or clopidogrel (10 mg/kg) along with HC feeding exhibited reduction in platelet activation as well as subsequent changes observed in the abovementioned parameters following HC feeding. Since reduction in TNF-α was associated with reversion in endothelial dysfunction and prothrombotic state, the role of platelets is implicated in the pathological changes associated with HC feeding.