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Background: The incidence of diabetes mellitus (DM) in China is increasing yearly and has become a major problem plaguing national public health. The diagnosis of diabetic kidney disease (DKD) is based primarily on clinical criteria, and most patients do not receive a formal evaluation by renal biopsy; thus, misdiagnosis and underdiagnosis are common. The incidence of non-diabetic kidney disease (NDKD) is also higher in those with DM. To date, many cases of IgA nephropathy (IgAN) among those with DKD have been reported, while cases of IgAN in patients with long-duration DM who did not develop DKD are less commonly reported. Case description: A 70-year-old male patient with a diabetes duration of 26 years had proteinuria for one year. The clinical manifestations of nephrotic syndrome and IgAN were confirmed by renal biopsy. The patient received targeted treatment for three years with partial alleviation of proteinuria. Conclusion: Renal biopsy might aid in the definitive diagnosis of DKD, NDKD, and NDKD combined with DKD. Precise therapy based on renal pathology might help to improve outcomes in the kidney. [ABSTRACT FROM AUTHOR]

Maternal high-fat diet (HFD) is associated with metabolic syndrome and cardiovascular diseases in adult offspring. Our previous study demonstrated that maternal HFD enhances pressor responses to ANG II or a proinflammatory cytokine (PIC), which is associated with increased expression of brain renin-angiotensin system (RAS) components and PICs in adult offspring. The present study further investigated whether inhibition of angiotensin-converting enzyme (ACE) or tumor necrosis factor-α (TNF-α) blocks sensitization of ANG II hypertension in offspring of HFD dams. All offspring were bred from dams with normal fat diet (NFD) or HFD starting two weeks before mating and maintained until weaning of the offspring. Then the weaned offspring were treated with an ACE inhibitor (captopril) or a TNF-α inhibitor (pentoxifylline) in the drinking water through the end of testing with a slow-pressor dose of ANG II. RT-PCR analyses of the lamina terminalis and paraventricular nucleus revealed upregulation of mRNA expression of several RAS components and PICs in male offspring of HFD dams when compared with age-matched offspring of NFD dams. The enhanced gene expression was attenuated by blockade of either RAS or PICs. Likewise, ANG II administration produced an augmented pressor response in offspring of HFD dams. This was abolished by either ACE or TNF-α inhibitor. Taken together, this study provides mechanistic evidence and a therapeutic strategy that systemic inhibition of the RAS and PICs can block maternal HFD-induced sensitization of ANG II hypertension, which is associated with attenuation of brain RAS and PIC expression in offspring. [ABSTRACT FROM AUTHOR]

Influenza is a persistent threat to public health. Here we report that double-layered peptide nanoparticles induced robust specific immunity and protected mice against heterosubtypic influenza A virus challenges. We fabricated the nanoparticles by desolvating a composite peptide of tandem copies of nucleoprotein epitopes into nanoparticles as cores and cross-linking another composite peptide of four tandem copies of influenza matrix protein 2 ectodomain epitopes to the core surfaces as a coating. Delivering the nanoparticles via dissolvable microneedle patch-based skin vaccination further enhanced the induced immunity. These peptide-only, layered nanoparticles demonstrated a strong antigen depot effect and migrated into spleens and draining (inguinal) lymph nodes for an extended period compared with soluble antigens. This increased antigen-presentation time correlated with the stronger immune responses in the nanoparticle-immunized group. The protection conferred by nanoparticle immunization was transferable by passive immune serum transfusion and depended partially on a functional IgG receptor FcγRIV. Using a conditional cell depletion, we found that CD8+ T cells were involved in the protection. The immunological potency and stability of the layered peptide nanoparticles indicate applications for other peptide-based vaccines and peptide drug delivery. [ABSTRACT FROM AUTHOR]

Accumulating evidence indicates that maternal high-fat diet (HFD) is associated with metabolic syndrome and cardiovascular disease in adult offspring. The present study tested the hypothesis that maternal HFD modulates the brain reninangiotensin system (RAS), oxidative stress, and proinflammatory cytokines that alter angiotensin II (ANG II) and TNF-α actions and sensitize the ANG II-elicited hypertensive response in adult offspring. All offspring were cross fostered by dams on the same or opposite diet to yield the following four groups: offspring from normal-fat control diet-fed dams suckled by control diet-fed dams (OCC group) or by HFD-fed dams (OCH group) and offspring from HFD-fed dams fed a HFD suckled by control diet-fed dams (OHC group) or by HFD-fed dams (OHH group). RT-PCR analyses of the lamina terminalis and paraventricular nucleus indicated upregulation of mRNA expression of several RAS components, NADPH oxidase, and proinflammatory cytokines in 10-wk-old male offspring of dams fed a HFD during either pregnancy, lactation, or both (OHC, OCH, and OHH groups). These offspring also showed decreased cardiac baroreflex sensitivity and increased pressor responses to intracerebroventricular microinjection of either ANG II or TNF-α. Furthermore, chronic systemic infusion of ANG II resulted in enhanced upregulation of mRNA expression of RAS components, NADPH oxidase, and proinflammatory cytokines in the lamina terminalis and paraventricular nucleus and an augmented hypertensive response in the OHC, OCH, and OHH groups compared with the OCC group. The results suggest that maternal HFD blunts cardiac baroreflex function and enhances pressor responses to ANG II or proinflammatory cytokines through upregulation of the brain RAS, oxidative stress, and inflammation. NEW & NOTEWORTHY The results of our study indicate that a maternal high-fat diet during either pregnancy or lactation is sufficient for perinatal programming of sensitization for hypertension, which is associated with hyperreactivity of central cardiovascular nuclei that, in all likelihood, involves elevated expression of the renin-angiotensin system, NADPH oxidase, and proinflammatory cytokines. The present study demonstrates, for the first time, the central mechanism underlying maternal high-fat diet sensitization of the hypertensive response in adult offspring. [ABSTRACT FROM AUTHOR]

Accumulating evidence indicates that maternal high-fat diet (HFD) is associated with metabolic syndrome and cardiovascular disease in adult offspring. The present study tested the hypothesis that maternal HFD modulates the brain reninangiotensin system (RAS), oxidative stress, and proinflammatory cytokines that alter angiotensin II (ANG II) and TNF-α actions and sensitize the ANG II-elicited hypertensive response in adult offspring. All offspring were cross fostered by dams on the same or opposite diet to yield the following four groups: offspring from normal-fat control diet-fed dams suckled by control diet-fed dams (OCC group) or by HFD-fed dams (OCH group) and offspring from HFD-fed dams fed a HFD suckled by control diet-fed dams (OHC group) or by HFD-fed dams (OHH group). RT-PCR analyses of the lamina terminalis and paraventricular nucleus indicated upregulation of mRNA expression of several RAS components, NADPH oxidase, and proinflammatory cytokines in 10-wk-old male offspring of dams fed a HFD during either pregnancy, lactation, or both (OHC, OCH, and OHH groups). These offspring also showed decreased cardiac baroreflex sensitivity and increased pressor responses to intracerebroventricular microinjection of either ANG II or TNF-α. Furthermore, chronic systemic infusion of ANG II resulted in enhanced upregulation of mRNA expression of RAS components, NADPH oxidase, and proinflammatory cytokines in the lamina terminalis and paraventricular nucleus and an augmented hypertensive response in the OHC, OCH, and OHH groups compared with the OCC group. The results suggest that maternal HFD blunts cardiac baroreflex function and enhances pressor responses to ANG II or proinflammatory cytokines through upregulation of the brain RAS, oxidative stress, and inflammation. [ABSTRACT FROM AUTHOR]

Background: Jumonji C domain 2A (JMJD2A), as a histone demethylases, plays a vital role in tumorigenesis and progression. But, its functions and underlying mechanisms of JMJD2A in nasopharyngeal carcinoma (NPC) metabolism are remained to be clarified. In this study, we investigated glycolysis regulation by JMJD2A in NPC and the possible mechanism.Methods: JMJD2A expression was detected by Western blotting and Reverse transcription quantitative real-time PCR analysis. Then, we knocked down and ectopically expressed JMJD2A to detect changes in glycolytic enzymes. We also evaluated the impacts of JMJD2A-lactate dehydrogenase A (LDHA) signaling on NPC cell proliferation, migration and invasion. ChIP assays were used to test whether JMJD2A bound to the LDHA promoter. Finally, IHC was used to verify JMJD2A and LDHA expression in NPC tissue samples and analyze their correlation between expression and clinical features.Results: JMJD2A was expressed at high levels in NPC tumor tissues and cell lines. Both JMJD2A and LDHA expression were positively correlated with the tumor stage, metastasis and clinical stage. Additionally, the level of JMJD2A was positively correlated with LDHA expression in NPC patients, and higher JMJD2A and LDHA expression predicted a worse prognosis. JMJD2A alteration did not influence most of glycolytic enzymes expression, with the exception of PFK-L, PGAM-1, LDHB and LDHA, and LDHA exhibited the greatest decrease in expression. JMJD2A silencing decreased LDHA expression and the intracellular ATP level and increased LDH activity, lactate production and glucose utilization, while JMJD2A overexpression produced the opposite results. Furthermore, JMJD2A could combine to LDHA promoter region and regulate LDHA expression at the level of transcription. Activated JMJD2A-LDHA signaling pathway promoted NPC cell proliferation, migration and invasion.Conclusions: JMJD2A regulated aerobic glycolysis by regulating LDHA expression. Therefore, the novel JMJD2A-LDHA signaling pathway could contribute to the Warburg effects in NPC progression. [ABSTRACT FROM AUTHOR]

Objective The objective is to perform a comprehensive review of the literature up to 2015 on the genetics and precision medicine relevant to otitis media. Data Sources PubMed database of the National Library of Medicine. Review Methods Two subpanels were formed comprising experts in the genetics and precision medicine of otitis media. Each of the panels reviewed the literature in their respective fields and wrote draft reviews. The reviews were shared with all panel members, and a merged draft was created. The entire panel met at the 18th International Symposium on Recent Advances in Otitis Media in June 2015 and discussed the review and refined the content. A final draft was made, circulated, and approved by the panel members. Conclusion Many genes relevant to otitis media have been identified in the last 4 years in advancing our knowledge regarding the predisposition of the middle ear mucosa to commensals and pathogens. Advances include mutant animal models and clinical studies. Many signaling pathways are involved in the predisposition of otitis media. Implications for Practice New knowledge on the genetic background relevant to otitis media forms a basis of novel potential interventions, including potential new ways to treat otitis media. [ABSTRACT FROM AUTHOR]

Background: The Ebola virus disease spread rapidly in West Africa in 2014, leading to the loss of thousands of lives. Community engagement was one of the key strategies to interrupt Ebola transmission, and practical community level measures needed to be explored in the field and tailored to the specific context of communities. Methods: First, community-level education on Ebola virus disease (EVD) prevention was launched for the community's social mobilizers in six districts in Sierra Leone beginning in November 2014. Then, from January to May of 2015, in three pilot communities, local trained community members were organized to engage in implementation of EVD prevention and transmission interruption measures, by involving them in alert case report, contact tracing, and social mobilization. The epidemiological indicators of transmission interruption in three study communities were evaluated. Results: A total of 6 016 community social mobilizers from 185 wards were trained by holding 279 workshops in the six districts, and EVD message reached an estimated 631 680 residents. In three pilot communities, 72 EVD alert cases were reported, with 70.8% of them detected by trained local community members, and 14 EVD cases were finally identified. Contact tracing detected 64.3% of EVD cases. The median duration of community infectivity for the cases was 1 day. The secondary attack rate was 4.2%, and no third generation of infection was triggered. No health worker was infected, and no unsafe burial and noncompliance to EVD control measures were recorded. The community-based measures were modeled to reduce 77 EVD cases, and the EVD-free goal was achieved four months earlier in study communities than whole country of Sierra Leone. Conclusions: The community-based strategy of social mobilization and community engagement was effective in case detection and reducing the extent of Ebola transmission in a country with weak health system. The successfully practical experience to reduce the risk of Ebola transmission in the community with poor resources would potentially be helpful for the global community to fight against the EVD and the other diseases in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND We compared admission systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), and mean arterial pressure (MAP) in predicting 30-day all-cause mortality in patients with ST-segment elevation myocardial infarction (STEMI) without cardiogenic shock. METHODS A retrospective study was performed in 7,033 consecutive STEMI patients. Multivariate-adjusted hazard ratios (HRs) with a 10mm Hg increment and quartiles of each blood pressure were determined by Cox proportional hazard analyses; Wald χ² tests were used to compare the strength of relationships. RESULTS Totally 593 (8.4%) patients died during follow-up. Of 4 indexes, only SBP (HR 0.94 per 10mm Hg, 95% confidence interval (CI) 0.91 to 0.98; P = 0.001 ) and PP (HR 0.89 per 10 mmHg, 95% CI 0.85 to 0.94; P < 0.001 ) were significantly associated with 30-day all-cause mortality; these in the highest vs. lowest quartiles of SBP (≥140 vs. <110mm Hg) and PP (≥60 vs. <40mm Hg) had HRs of mortality of 0.70 (95% CI 0.55 to 0.87; P = 0.003) and 0.60 (95% CI 0.47 to 0.75; P < 0.001), respectively. Compared with SBP, PP was a better predictor for mortality no matter in men (χ² = 5.9 for per 10mm Hg, χ² = 10.8 for quartiles) or women (χ² = 15.1 for per 10 mm Hg, χ² = 19.5 for quartiles), and the relationship remained significant after adjustment of SBP. There was a pattern of declining risk with increasing blood pressures for mortality, and this trend was mainly observed in age groups of more than 70 years. CONCLUSIONS Pulse pressure was an independent predictor of mortality in patients with STEMI, and low admission blood pressure should serve as a warning sign. [ABSTRACT FROM AUTHOR]

Myeloid differentiation factor 88 (MyD88) acts as a crucial adaptor molecule for Toll-like receptors (TLRs) and interleukin (IL)-1 receptor signaling. In contrast to the well-studied positive regulation of MyD88 signaling, how MyD88 signaling is negatively regulated still remains largely unknown. Here, we demonstrate for the first time to our knowledge that MyD88 protein undergoes lysine 63 (K63)-linked polyubiquitination, which is functionally critical for mediating TLR-MyD88-dependent signaling. Deubiquitinase CYLD negatively regulates MyD88-mediated signaling by directly interacting with MyD88 and deubiquitinating nontypeable Haemophilus influenzae (NTHi)-induced K63-linked polyubiquitination of MyD88 at lysine 231. Importantly, we further confirmed this finding in the lungs of mice in vivo by using MyD88-/-CYLD-/- mice. Understanding how CYLD deubiquitinates K63-linked polyubiquitination of MyD88 may not only bring insights into the negative regulation of TLR-MyD88-dependent signaling, but may also lead to the development of a previously unidentified therapeutic strategy for uncontrolled inflammation. [ABSTRACT FROM AUTHOR]

Background: Recent studies demonstrate that there are sex differences in the expression of angiotensin receptor type 2 (AT2-R) in the kidney and that AT2-R plays an enhanced role in regulating blood pressure (BP) in females. Also, brain AT2-R activation has been reported to negatively modulate BP and sympathetic outflow. The present study investigated whether the central blockade of endogenous AT2-R augments deoxycorticosterone acetate (DOCA)/salt-induced hypertension in both male and female rats. Methods: All rats were subcutaneously infused with DOCA combined with 1% NaCl solution as the sole drinking fluid. BP and heart rate (HR) were recorded by telemetric transmitters. To determine the effect of central AT2-R on DOCA/ salt-induced hypertension, male and female rats were intracerebroventricularly (icv) infused with AT2-R antagonist, PD123,319, during DOCA/salt treatment. Subsequently, the paraventricular nucleus (PVN) of the hypothalamus, a key cardiovascular regulatory region of the brain, was analyzed by quantitative real-time PCR and Western blot. Results: DOCA/salt treatment elicited a greater increase in BP in male rats than that in females. Icv infusions of the AT2-R antagonist significantly augmented DOCA/salt pressor effects in females. However, this same treatment had no enhanced effect on DOCA/salt-induced increase in the BP in males. Real-time PCR and Western blot analysis of the female brain revealed that DOCA/salt treatment enhanced the mRNA and protein expression for both antihypertensive components including AT2-R, angiotensin-converting enzyme (ACE)-2, and interleukin (IL)-10 and hypertensive components including angiotensin receptor type 1 (AT1-R), ACE-1, tumor necrosis factor (TNF)-α, and IL-1β, but decreased mRNA expression of renin in the PVN. The central blockade of AT2-R reversed the changes in mRNA and protein expressions of ACE-2, IL-10, and renin, further increased the expressions of TNF-α and IL-1β, and kept higher the expressions of AT1-R, ACE-1, and AT2-R. Conclusions: These results indicate that endogenous AT2-R activation in the brain plays an important protective role in the development of DOCA/salt-induced hypertension in females, but not in males. The protective effect of AT2-R in females involves regulating the expression of brain renin-angiotensin system components and proinflammatory cytokines. [ABSTRACT FROM AUTHOR]

Background: Acute gastrointestinal illness (AGI) imposes considerable social and economic burden on low and middle-income countries. This study aimed to estimate the occurrence, distribution, and burden of self-reported AGI in Gansu Province of northwest China, where economic growth rates have lagged far behind those of other regions in China and systematic studies to investigate the burden of AGI are still lacking. Methods: Twelve-month, retrospective face-to-face surveys were conducted in three sentinel sites between June 2012 and May 2013. Respondents were asked if they had experienced diarrhoea or vomiting in the 28 days prior to the interview. Results: In total, 2094 interviews were completed. The adjusted monthly prevalence was 8.5% with an incidence rate of 1.16 episodes of AGI per person-year. Healthcare was sought by 73.8% of those reporting illness. Of the cases who visited a doctor, 50.5% submitted a stool sample. The use of antibiotics was reported by 65.6% of the cases and 53.3% took antidiarrhoeals. In the multivariable model, age, household income and sentinel site were significant risk factors of being a case of AGI. Conclusions: The burden of AGI was considerable in Gansu Province of northwest China. Ongoing research to identify the main causes of AGI is needed for more accurate estimate of the burden of AGI in this region. [ABSTRACT FROM AUTHOR]

Background: Inflammation is a hallmark of many serious human diseases. Nontypeable Haemophilus influenzae (NTHi) is an important human pathogen causing respiratory tract infections in both adults and children. NTHi infections are characterized by inflammation, which is mainly mediated by nuclear transcription factor-kappa B (NF-κB)-dependent production of proinflammatory mediators. Epidermal growth factor receptor (EGFR) has been shown to play important roles in regulating diverse biological processes, including cell growth, differentiation, apoptosis, adhesion, and migration. Its role in regulating NF-κB activation and inflammation, however, remains largely unknown. Methodology/Principal Findings: In the present study, we demonstrate that EGFR plays a vital role in NTHi-induced NF-κB activation and the subsequent induction of proinflammatory mediators in human middle ear epithelial cells and other cell types. Importantly, we found that AG1478, a specific tyrosine kinase inhibitor of EGFR potently inhibited NTHiinduced inflammatory responses in the middle ears and lungs of mice in vivo. Moreover, we found that MKK3/6-p38 and PI3K/Akt signaling pathways are required for mediating EGFR-dependent NF-κB activation and inflammatory responses by NTHi. Conclusions/Significance: Here, we provide direct evidence that EGFR plays a critical role in mediating NTHi-induced NF-κB activation and inflammation in vitro and in vivo. Given that EGFR inhibitors have been approved in clinical use for the treatment of cancers, current studies will not only provide novel insights into the molecular mechanisms underlying the regulation of inflammation, but may also lead to the development of novel therapeutic strategies for the treatment of respiratory inflammatory diseases and other inflammatory diseases. [ABSTRACT FROM AUTHOR]

Human astroviruses (HAstVs) are one of the major viral agents of acute gastroenteritis (AGE) in all age groups, especially in young children. In this study, new one-step real-time RT-PCR and nested RT-PCR assays were developed to detect HAstVs. HAstVs were identified in 46 (8.75%) of 526 stool samples in Jiangmen City over 1 year, including 43 (9.15%) of 470 children and 3 (5.4%) of 56 adults, and HAstV-1 was the most predominant strain. This finding suggests that HAstVs infections are common in Jiangmen City, China. Further detailed molecular epidemiological studies are required for understanding the prevalence of HAstVs infection and gaining knowledge about the circulating genotypes. [ABSTRACT FROM AUTHOR]

Inflammation is a hallmark of many diseases, such as atherosclerosis, chronic obstructive pulmonary disease, arthritis, infectious diseases, and cancer. Although steroids and cyclooxygenase inhibitors are effective antiinflammatory therapeutical agents, they may cause serious side effects. Therefore, developing unique antiinflammatory agents without significant adverse effects is urgently needed. Vinpocetine, a derivative of the alkaloid vincamine, has long been used for cerebrovascular disorders and cognitive impairment Its role in inhibiting inflammation, however, remains unexplored. Here, we show that vinpocetine acts as an antiinflammatory agent in vitro and in vivo. In particular, vinpocetine inhibits TNF-α-induced NF-κB activation and the subsequent induction of proinflammatory mediators in multiple cell types, including vascular smooth muscle cells, endothelial cells, macrophages, and epithelial cells. We also show that vinpocetine inhibits monocyte adhesion and chemotaxis, which are critical processes during inflammation. Moreover, vinpocetine potently inhibits TNF-α- or LPS-induced up-regulation of proinflammatory mediators, including TNF-α, lL-1β, and macrophage inflammatory protein-2, and decreases interstitial infiltration of polymorphonuclear leukocytes in a mouse model of TNF-α- or LPSinduced lung inflammation. Interestingly, vinpocetine inhibits NF-κB-dependent inflammatory responses by directly targeting IKK, independent of its well-known inhibitory effects on phosphodiesterase and Ca2+ regulation. These studies thus identify vinpocetine as a unique antiinflammatory agent that may be repositioned for the treatment of many inflammatory diseases. [ABSTRACT FROM AUTHOR]

Distributed power control is investigated for cognitive radio networks (CRNs) based on a cooperative game-theoretic framework. Taking into consideration both network efficiency and user fairness, a cooperative Nash bargaining power-control game (NBPCG) model is formulated, where interference power constraints (IPCs) are imposed to protect the primary users' (PUs') transmissions, and minimum signal-to-interference-plus-noise ratio (SINR) requirements are employed to provide reliable transmission opportunities to secondary cognitive users. An SINR-based utility function is designed for this game model, which not only reflects the spectrum efficiency of the CRN but also complies with all the axioms in the Nash theorem and, hence, facilitates efficient algorithmic development. The existence, uniqueness, and fairness of this game solution are proved analytically. To deal with the IPCs where the power-control decisions of all users are coupled, these IPCs are properly transformed into a pricing function in the objective utility. Accordingly, a Kalai-Smorodinsky (KS) bargaining solution and a Nash bargaining solution (NBS) are developed, which result in Pareto-optimal solutions to the NBPCG problem with different user-fairness policies. Theoretical analysis and simulations are provided to testify the effectiveness of the proposed cooperative game algorithms for efficient and fair power control in CRNs. [ABSTRACT FROM AUTHOR]

Aim: Noroviruses (NoVs) are an important cause of acute gastroenteritis but knowledge on the disease burden and epidemiology in children in the developing countries remains limited. In this study, we performed a surveillance of NoV gastroenteritis in children of China to address some of the questions. Methods: Faecal specimens from children (<5 years of age) at outpatient clinics of the Nan Fang Hospital in Guangzhou, China during the fall–winter seasons in 2003–2006 were tested for rotaviruses (RVs) and NoVs. A questionnaire on clinical records and hygiene habits was collected from each patient. Results: Among 957 stool specimens tested, 488 (51%) specimens were positive for RVs. NoVs were detected in 112 (24%) of the 469 RV negative specimens. The Genogroup II (GII), particularly GII-4, viruses were predominant. No significant difference of clinical symptoms, hospitalisation and patient care expenses were found between children infected with NoVs and RVs. Consumption of uncooked food is a risk for NoV infection. Contact with diarrhoea patients is a suspected risk factor. Cutting nails frequently is a protective factor against NoV infection. Conclusions: NoVs are an important cause of acute gastroenteritis in children which need special attention of patient care at the clinics in addition to RVs. The awareness of those risk factors may help future disease control and prevention. [ABSTRACT FROM AUTHOR]

Background: Legionella pneumophila is the causative agent of human Legionnaire's disease. During infection, the bacterium invades macrophages and lung epithelial cells, and replicates intracellularly. However, little is known about its interaction with T cells. We investigated the ability of L. pneumophila to infect and stimulate the production of interleukin-8 (IL-8) in T cells. The objective of this study was to assess whether L. pneumophila interferes with the immune system by interacting and infecting T cells. Results: Wild-type L. pneumophila and flagellin-deficient Legionella, but not L. pneumophila lacking a functional type IV secretion system Dot/Icm, replicated in T cells. On the other hand, wild-type L. pneumophila and Dot/Icm-deficient Legionella, but not flagellin-deficient Legionella or heat-killed Legionella induced IL-8 expression. L. pneumophila activated an IL-8 promoter through the NF-κB and AP-1 binding regions. Wild-type L. pneumophila but not flagellin-deficient Legionella activated NF-κB, p38 mitogen-activated protein kinase (MAPK), Jun N-terminal kinase (JNK), and transforming growth factor β-associated kinase 1 (TAK1). Transfection of dominant negative mutants of |κBα, |κB kinase, NF-κB-inducing kinase, TAK1, MyD88, and p38 MAPK inhibited L. pneumophila-induced IL-8 activation. Inhibitors of NF-κB, p38 MAPK, and JNK blocked L. pneumophila-induced IL-8 expression. In addition, c-Jun, JunD, cyclic AMP response element binding protein, and activating transcription factor 1, which are substrates of p38 MAPK and JNK, bound to the AP-1 site of the IL-8 promoter. Conclusions: Taken together, L. pneumophila induced a flagellin-dependent activation of TAK1, p38 MAPK, and JNK, as well as NF-κB and AP-1, which resulted in IL-8 production in human T cells, presumably contributing to the immune response in Legionnaire's disease. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence has suggested that differentiation of adventitial fibroblasts (AFs) to myofibroblasts plays an important role in arterial remodeling. The molecular mechanisms by which myofibroblast formation is regulated still remain largely unknown. This study aimed to evaluate the role of cyclic nucleotide phosphodiesterase 1A (PDE1A) in the formation of adventitial myofibroblasts induced by transforming growth factor (TGF)-β1. Methods and Results: AFs were cultured by the explant method. Western blot and immunocytochemistry were applied for α-smooth muscle actin (SMA) or protein kinase C (PKC) α protein analysis. Results showed that TGF-β1 upregulated PDE1A protein expression in rat aortic AFs and pharmacological inhibition of PDE1A blocked TGF-β1-induced α-SMA expression, a marker of myofibroblast formation, suggesting that the upregulation of PDE1A may mediate TGF-β1-induced AF transformation. Moreover, calphostin C (a PKC inhibitor) inhibited TGF-β1-induced α-SMA expression, whereas phorbol-12-myristate-13-acetate (a PKC activator) induced it. Finally, the upregulation of PKCα expression by TGF-β1 was also inhibited by PDE1A inhibition. Conclusions: Taken together, our data suggest that TGFβ1 induces α-SMA expression and myofibroblast formation via a PDE1A-PKCα-dependent mechanism. Our study thus unveils a novel signaling mechanism underlying TGF-β1-induced adventitial myofibroblast formation. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The TGF-β (transforming growth factor-β) pathway represents an important signalling pathway involved in regulating diverse biological processes, including cell proliferation, differentiation and inflammation. Despite the critical role for TGF-β in inflammatory responses, its role in regulating NF-κB (nuclear factor-κB)-dependent inflammatory responses still remains unknown. In the present study we show that TGF-β1 synergizes with proinflammatory cytokine TNF-α (tumour necrosis factor-α) to induce NF-κB activation and the resultant inflammatory response in vitro and in vivo. TGF-β1 synergistically enhances TNF-α-induced NF-κB DNA binding activity via induction of RelA acetylation. Moreover, synergistic enhancement of TNF-α-induced RelA acetylation and DNA-binding activity by TGF-β1 is mediated by PKA (protein kinase A). Thus the present study reveals a novel role for TGF-β in inflammatory responses and provides new insight into the regulation of NF-κB by TGF-β signalling. [ABSTRACT FROM AUTHOR]

Bacteraemic pneumonia is a common cause of sepsis in critically ill patients today and is characterized by dysregulation of inflammation. The genetic factors predisposing to bacteraemic pneumonia are not yet fully understood. Innate immunity is pivotal for host defence against invading bacteria, and nuclear factor-kappa B (NF-κB) is central to bacteria-induced inflammation and immune responses. The deubiquitinating enzyme CYLD has been identified as a key negative regulator for NF-κB . In the present study, we investigated the role of CYLD in innate immune response in Escherichia coli pneumonia. Upon E. coli inoculation, Cyld−/− mice were hypersusceptible to E. coli pneumonia with higher mortality. Innate immune response to E. coli was enhanced in Cyld−/− cells and mice. Cyld−/− cells exhibited enhanced NF-κB activation upon E. coli inoculation, and the enhanced NF-κB activation by E. coli was abolished by perturbing IκB kinase (IKK) signalling. Furthermore, IKK inhibitor rescued Cyld−/− mice from lethal infection during E. coli pneumonia along with reduced inflammation. Taken together, these data showed that CYLD acts as a crucial negative regulator for E. coli pneumonia by negatively regulating NF-κB. These findings provide novel insight into the regulation of bacteraemic pneumonia and related diseases and may help develop novel therapeutic strategies for these diseases. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLRs) are important sensors of microbial pathogens and mediators of innate immune responses. Although the signal transduction of TLRs is well elucidated, their basal regulation is largely unexplored. Here we show that the tumor suppressor p53 positively regulates the transcription of TLR3, a receptor for viral double-stranded RNA and poly(I-C), by binding to the p53 site in the TLR3 promoter. TLR3 expression was lower in HCT116 p53-/- cells than in HCT116 p53+/+ cells. Activation of p53 by 5-fluorouracil increased the TLR3 mRNA in epithelial cell lines with wild-type p53 but not in cell lines harboring mutant p53. Knockdown of p53 by small interfering RNA decreased the TLR3 expression. TLR3 mRNA was also lower in liver and intestine of p53-/- mice than in p53+/+ mice. Furthermore, the poly(I-C)-induced phosphorylation of Iκ B-α, nuclear translocation of NF-κ B, and phosphorylation of interferon regulatory transcription factor 3, were drastically reduced in HCT116 p53-/- cells, indicating a dysregulation of the two signaling pathways governed by TLR3. Consequently, induction of interleukin-8 and beta interferon after poly(I-C) stimulation was impaired in HCT116 p53-/- cells. These results suggest that p53 influences TLR3 expression and function and highlight a role of p53 in innate immune response in epithelial cells. [ABSTRACT FROM AUTHOR]

Background: Nontypeable Haemophilus influenzae (NTHi) is an important respiratory pathogen implicated as an infectious trigger in chronic obstructive pulmonary disease, but its molecular interaction with human lung epithelial cells remains unclear. Herein, we tested that the hypothesis that NTHi induces the expression of cyclooxygenase (COX)-2 and prostaglandin E2 (PGE2) via activation of p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappa B in pulmonary alveolar epithelial cells. Methods: Human alveolar epithelial A549 cells were infected with different concentrations of NTHi. The phosphorylation of p38 MAPK was detected by Western blot analysis, the DNA binding activity of NF-kappa B was assessed by electrophoretic mobility shift assay (EMSA), and the expressions of COX-1 and 2 mRNA and PGE2 protein were measured by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA), respectively. The roles of Toll-like receptor (TLR) 2 and TLR4, well known NTHi recognizing receptor in lung epithelial cell and gram-negative bacteria receptor, respectively, on the NTHi-induced COX-2 expression were investigated in the HEK293 cells overexpressing TLR2 and TLR4 in vitro and in the mouse model of NTHi-induced pneumonia by using TLR2 and TLR4 knock-out mice in vivo. In addition, the role of p38 MAPK and NF-kappa B on the NTHi-induced COX-2 and PGE2 expression was investigated by using their specific chemical inhibitors. Results: NTHi induced COX-2 mRNA expression in a dose-dependent manner, but not COX-1 mRNA expression in A549 cells. The enhanced expression of PGE2 by NTHi infection was significantly decreased by pre-treatment of COX-2 specific inhibitor, but not by COX-1 inhibitor. NTHi induced COX-2 expression was mediated by TLR2 in the epithelial cell in vitro and in the lungs of mice in vivo. NTHi induced phosphorylation of p38 MAPK and up-regulated DNA binding activity of NF-kappa B. Moreover, the expressions of COX-2 and PGE2 were significantly inhibited by specific inhibitors of p38 MAPK and NF-kappa B. However, NTHi-induced DNA binding activity of NF-kappa B was not affected by the inhibition of p38 MAPK. Conclusion: NTHi induces COX-2 and PGE2 expression in a p38 MAPK and NF-kappa B-dependent manner through TLR2 in lung epithelial cells in vitro and lung tissues in vivo. The full understanding of the role of endogenous anti-inflammatory PGE2 and its regulation will bring new insight to the resolution of inflammation in pulmonary bacterial infections. [ABSTRACT FROM AUTHOR]

Background: Toll-like receptor 2 (TLR2) plays a critical role in mediating inflammatory/immune responses against bacterial pathogens in lung. Streptococcus pneumoniae (S. pneumoniae) and nontypeable Haemophilus influenzae (NTHi) were previously reported to synergize with each other to induce inflammatory responses. Despite the relatively known intracellular signaling pathways involved in the synergistic induction of inflammation, it is still unclear if both bacterial pathogens also synergistically induce expression of surface TLR2. Results: Here we provide direct evidence that S. pneumoniae synergizes with NTHi to upregulate TLR2 expression in lung and middle ear of the mice. Pneumolysin (PLY) appears to be the major virulence factor involved in this synergism. Moreover, S. pneumoniae PLY induces TLR2 expression via a TLR4-MyD88-NF-κB-dependent signaling pathway. Interestingly, tumor suppressor CYLD acts as a negative regulator of S. pneumoniae-induced TLR2 up-regulation via negative-crosstalk with NF-κB signaling. Conclusion: Our study thus provides novel insights into the regulation of TLR2 expression in mixed bacterial infections. [ABSTRACT FROM AUTHOR]

Transforming growth factor-β (TGF-β) family members are multifunctional growth factors involved in regulating diverse biological processes. Despite the critical role for TGF-β in regulating cell proliferation, differentiation, migration and development, its role in regulating NF-κB-dependent inflammatory response still remains unclear. Here, we show that TGF-β1 induces acetylation of NF-κB p65 subunit to synergistically enhance bacterium nontypeable Haemophilus influenzae-induced NF-κB activation and inflammatory response in vitro and in vivo. The TGF-β1-induced acetylation of p65 is mediated via a Smad3/4-PKA-p300-dependent signaling pathway. Acetylation of p65 at lysine 221 by TGF-β1 is critical for synergistic enhancement of bacteria-induced DNA-binding activity, NF-κB activation, NF-κB-dependent transcription of TNF-α and IL-1β and interstitial polymorphonuclear neutrophil infiltration in vitro and in vivo. These studies provide new insights into the novel regulation of NF-κB by TGF-β signaling. [ABSTRACT FROM AUTHOR]

The molecular mechanisms responsible for TNF-α-mediated MUC2 intestinal mucin up-regulation in HM3 colon adenocarcinoma cells were analyzed using promoter-reporter assays of the 5’-flanking region of the MUC2 gene. Chemical inhibitors, mutant reporter constructs, and EMSA confirmed I-kappaB/NF-kappaB pathway involvement. Wortmannin, LY294002 and dominant negative Akt, as well as dominant negative NF-kappaB-inducing kinase (NIK) inhibited MUC2 reporter transcription, indicating that both phosphatidylinositol-3-OH kinase (PI3K)/Akt signaling pathway and NIK pathways mediate the effects of TNF-alpha. Wortmannin inhibited NF-kappaB binding and transcriptional activity without inhibiting NF-kappaB translocation to the nucleus, indicating that PI3K/Akt signaling activates NF-kappaB transcriptional activity directly. Our results demonstrate that TNF-alpha up-regulates MUC2 in human colon epithelial cells via several signaling pathways, involving both NIK and PI3K/Akt, which converge at the common IKK/I-kappaB/NF-kappaB pathway. TNF-alpha activated JNK, but JNK inhibitor SP600125 and dominant negative cJun consistently activated transcription, revealing a negative role for this signaling pathway. Thus TNF-alpha causes a net up-regulation of MUC2 gene expression in cultured colon cancer cells because NF-kappaB transcriptional activation of this gene is able to counter-balance the suppressive effects of the JNK pathway. However, the existence of this inhibitory JNK pathways suggests a mechanism whereby - in the absence of NF-kappaB activation - TNF-alpha production during inflammation in vivo could actually inhibit MUC2 production, giving rise to the defective mucosal protection which characterizes inflammatory bowel disease. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Presents research on interaction between middle ear and inner ear in otitis media. Role of inflammatory mediators in the development of the disease; Determination of the loss of outer hair cells in the base of the cochlea and other pathological changes in the inner ear; Indication of the destruction of gap junctions following otitis media.

Presents studies on the biochemistry of otitis media. Determination of the presence of several inflammatory mediators; Capability of tumor necrosis factor alpha to induce the acute phase of the inflammatory response and the release of other cytokines; Role of interleukin-4 in supporting the proliferation of activated T cells.

Presents studies on the molecular biology of otitis media. Evaluation of the expression of messenger RNA encoding vascular endothelial growth factor isoforms; Determination of the involvement of cytokines in mucin regulation; Identification of the casuses of the virally induced increase in nasopharyngeal colonization of bacteria.

Nontypeable Haemophilus influenzae (NTHi) is an Important human pathogen causing otitis media in children and exacerbation of chronic obstructive pulmonary disease in adults. Like most other bacterial infections, NTHi infections are also characterized by inflammation, which is mainly mediated by cytokines and chemokines such as tumor necrosis factor α (TNF-α). Among a variety of transcription regulators, NF-κB has been shown to play a critical role in regulating the expression of large numbers of genes encoding inflammatory mediators. In review of the current studies on NF-κB regulation, most of them have focused on investigating how NF-κB is activated by a single Inducer at a times. However, in bacteria-induced inflammation in vivo, multiple inducers including both exogenous and endogenous mediators are present simultaneously. A key issue that has yet to be addressed is whether the exogenous inducers such as NTHi and the endogenous factors such as TNF-α activate NF-κB in a synergistic manner. We show that NTHi and TNF-α, when present together, synergistically induce NF-κB activation via two distinct signaling pithways: NF-κB translocation-dependent and -independent pathways. The NF-κB translocation-dependent pathway involves NF-κB-inducing kinase-IκB kinase β/γ-dependent phosphorylation and degradation of IκBα, whereas the NF-κB translocation-independent pathway involves mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase kinase kinase 1-dependent activation of MAPK kinase 3/6-p38 MAPK pathway. In addition, the same signaling pathways are also involved in synergistic induction of TNF-α, IL-1β, and IL-8. These studies should deepen our understanding of the molecular mechanisms underlying the combinatorial regulation of inflammation and lead to development of therapeutic strategies for NTHi-induced infections. [ABSTRACT FROM AUTHOR]

Background: Despite its direct connection to the nasopharynx which harbors otitis media pathogens as part of its normal flora, the middle ear cavity is kept free of these bacteria by as yet unknown mechanisms. Respiratory mucosal epithelia, including those of the middle ear and eustachian tube, secrete antimicrobial effectors including lysozyme, lactoferrin and β defensins-1 and -2. To elucidate the role of these innate immune molecules in the normal defense and maintenance of sterility of respiratory mucosa such as that of the middle ear, we assessed their effect on the respiratory pathogens nontypeable Haemophilus influenzae (NTHi) 12, Moraxella catarrhalis 035E, and Streptococcus pneumoniae 3, and 6B. Methods: Two assay methods, the radial assay and the liquid broth assay, were employed for testing the antimicrobial activity of the molecules. This was done in order to minimize the possibility that the observed effects were artifacts of any single assay system employed. Also, transmission electron microscopy (TEM) was employed to evaluate the effect of antimicrobial innate immune molecules on OM pathogens. For the statistical analysis of the data, Student's t-test was performed. Results: Results of the radial diffusion assay showed that β defensin-2 was active against all four OM pathogens tested, while treatment with β defensin-1 appeared to only affect M. catarrhalis. The radial assay results also showed that lysozyme was quite effective against S. pneumoniae 3 and 6B and was partially bacteriostatic/bactericidal against M. catarrhalis. Lysozyme however, appeared not to affect the growth of NTHi. Thus, lysozyme seems to have a more pronounced impact on the growth of the Gram-positive S. pneumoniae as compared to that of Gram-negative pathogens. Lactoferrin on the other hand, enhanced the growth of the bacteria tested. The results of the radial assays were confirmed using liquid broth assays for antimicrobial activity, and showed that lysozyme and β defensin-2 could act synergistically against S. pneumoniae 6B. Moreover, in the liquid broth assay, β defensin-1 showed a modest inhibitory effect on the growth of S. pneumoniae 6B. As assessed by ultrastructural analysis, lysozyme and β defensin-2, and to a much lesser extent, β defensin-1, appeared to be able to cause damage to the bacterial membranes. Conclusions: Here we report that lysozyme and the β defensins can inhibit the growth of clinical isolates of otitis media pathogens -- namely NTHi strain 12, S. pneumoniae strains 3 and 6B and M. catarrhalis strain 035E - and cause ultrastructural damage to these pathogens. Moreover, we demonstrate that lysozyme and β defensin-2 can act synergistically against S. pneumoniae. These findings are consistent with the concept that secreted antimicrobial peptides and other components of innate immunity constitute the first line of defense protecting host mucosal surfaces, including the tubotympanal (eustachian tube and middle ear cavity) mucosa, against pathogens. [ABSTRACT FROM AUTHOR]

Background: Despite the importance of glucocorticoids in suppressing immune and inflammatory responses, their role in enhancing host immune and defense response against invading bacteria is poorly understood. Toll-like receptor 2 (TLR2) has recently gained importance as one of the major host defense receptors. The increased expression of TLR2 in response to bacteria-induced cytokines has been thought to be crucial for the accelerated immune response and resensitization of epithelial cells to invading pathogens. Results: We show that IL-1β, a key proinflammatory cytokine, greatly up-regulates TLR2 expression in human epithelial cells via a positive IKKβ-IκBα-dependent NF-κB pathway and negative MEKK1-MKK4/7-JNK1/2 and MKK3/6-p38 α/β pathways. Glucocorticoids synergistically enhance IL-1β-induced TLR2 expression via specific up-regulation of the MAP kinase phosphatase- 1 that, in turn, leads to dephosphorylation and inactivation of both MAPK JNK and p38, the negative regulators for TLR2 induction. Conclusion: These results indicate that glucocorticoids not only suppress immune and inflammatory response, but also enhance the expression of the host defense receptor, TLR2. Thus, our studies may bring new insights into the novel role of glucocorticoids in orchestrating and optimizing host immune and defense responses during bacterial infections and enhance our understanding of the signaling mechanisms underlying the glucocorticoid-mediated attenuation of MAPK. [ABSTRACT FROM AUTHOR]

Focuses on the study of the biochemistry and molecular biology of otitis media (OM). Characteristics of the biology of OM in the multiple interactions between microorganisms and protective responses of the host; Association of the inflammatory biology of the middle ear in the biochemistry of the OM; Identification of the factors involved in the chronicity of OM.

Investigates the activation of NF-kappaB transcription factor in human epithelial cells. Involvement of nontypeable Hemophilus influenza; Implication for therapeutic intervention for NTHi-induced infections; Molecular mechanism of NTHi-induced infections pathogenesis.

Presents a study which found that promoter hypomethylation of Toll-like receptor-2 (TLR2) gene is associated with increased proinflammatory response toward bacterial peptidoglycan in cystic fibrosis bronchial epithelial cells. Ability of 5-Azacytidine to increase TLR2 expression and demethylation in TLR2 proximal promoter; Factor that downregulates TLR2 expression and modulates PGN response by altering TLR2 promoter methylation; Conclusions and significance of the study.