Cellular Response Mechanisms in Porphyromonas gingivalis Infection

The pathogenicity of the periodontal biofilm is highly dependent on a few key species, of which Porphyromonas gingivalis is considered to be one of the most important pathogens. P. gingivalis expresses a broad range of virulence factors, of these cysteine proteases (gingipains) are of special importance both for the bacterial survival/proliferation and for the pathological outcome. Several cell types, for example, epithelial cells, endothelial cells, dendritic cells, osteoblasts, and fibroblasts, reside in the periodontium and are part of the innate host response, as well as platelets, neutrophils, lymphocytes, and monocytes/macrophages. These cells recognize and respond to P. gingivalis and its components through pattern recognition receptors (PRRs), for example, Toll-like receptors and protease-activated receptors. Ligation of PRRs induces downstream-signaling pathways modifying the activity of transcription factors that regulates the expression of genes linked to inflammation. This is followed by the release of inflammatory mediators, for example, cytokines and reactive oxygen species. Periodontal disease is today considered to play a significant role in various systemic conditions such as cardiovascular disease (CVD). The mechanisms by which P. gingivalis and its virulence factors interact with host immune cells and contribute to the pathogenesis of periodontitis and CVD are far from completely understood

Differential cytokine regulation by NF-κB and AP-1 in Jurkat T-cells

BACKGROUND: Activator protein (AP)-1 and nuclear factor (NF)-kappaB largely control T-cell activation, following binding of foreign antigens to the T-cell receptor leading to cytokine secretion. Elevated levels of pro-inflammatory cytokines and chemokines such as TNF, IL-6 and CXCL8 are associated with several human diseases including cystic fibrosis, pulmonary fibrosis and AIDS. The aim of this study was to investigate the role of the transcription factors, AP-1 and NF-kappaB, in IL-6 and CXCL8 regulation in Jurkat T-cells. RESULTS: Phorbol myristate acetate (PMA) exposure resulted in an up-regulation of AP-1 and down-regulation of NF-kappaB activity, however, exposure to heat killed (HK) Escherichia. coli MG1655 resulted in a dose-dependent increase in NF-kappaB activity without affecting AP-1. The cytokine profile revealed an up-regulation of the chemokine CXCL8 and the pro-inflammatory cytokines TNF, IL-2 and IL-6 following treatment with both PMA and HK E. coli, while the levels of the anti-inflammatory cytokine IL-10 were not affected by PMA but were significantly down-regulated by HK E. coli. AP-1 activation was significantly increased 2 h after PMA exposure and continued to increase thereafter. In contrast, NF-kappaB responded to PMA exposure by a rapid up-regulation followed by a subsequent down-regulation. Increased intracellular Ca2+ concentrations countered the down-regulation of NF-kappaB by PMA, while similar treatment with calcium ionophore resulted in a reduced NF-kappaB activity following induction with HK E. coli. In order to further study NF-kappaB activation, we considered two up-stream signalling proteins, PKC and Bcl10. Phosphorylated-PKC levels increased in response to PMA and HK E. coli, while Bcl10 levels significantly decreased following PMA treatment. Using an NF-kappaB activation inhibitor, we observed complete inhibition of IL-6 expression while CXCL8 levels only decreased by 40% at the highest concentration. Treatment of Jurkat T-cells with PMA in the presence of JNK-inhibitor suppressed both CXCL8 and IL-6 while PKC-inhibitor primarily decreased CXCL8 expression. CONCLUSION: The present study shows that NF-kappaB regulated IL-6 but not CXCL8. This complex regulation of CXCL8 suggests that there is a need to further evaluate the signalling pathways in order to develop new treatment for diseases with elevated CXCL8 levels, such as AIDS and autoimmune diseases

IMPLEMENTASI KURIKULUM ILMU PENGETAHUAN ALAM (IPA) DENGAN KEKHASAN SEKOLAH ALAM

Penelitian ini dilatarbelakangi dari fakta yang menunjukkan bahwa kepeduliaan terhadap lingkungan telah menurun. Maka diperlukan sebuah sistem pendidikan yang ramah terhadap lingkungan, seperti yang diterapkan di Sekolah Alam. Sekolah Alam merupakan sekolah yang menyatu dengan alam sehingga pembelajarannya lebih menekankan pada pembelajaran berbasis alam dan pengalaman. Ilmu Pengetahuan Alam (IPA) merupakan mata pelajaran yang sangat berkaitan dengan gejala dan objek yang ada di alam. Hal yang menjadi fokus penelitian adalah perencanaan, pelaksanaan dan penilaian dari pembelajaran IPA dengan kekhasan Sekolah Alam khususnya di SMP Sekolah Alam Bandung. Penelitian ini bertujuan untuk menganalisis implementasi kurikulum IPA dengan kekhasan Sekolah Alam. Penelitian ini menggunakan pendekatan kualitatif dengan metode studi kasus. Teknik pengumpulan data yang digunakan adalah studi dokumentasi, wawancara dan observasi. Hasil penelitian menunjukkan perencanaan pembelajaran IPA di SMP Sekolah Alam Bandung diawali dengan pembuatan Rencana Pembelajaran yang membagi mata pelajaran IPA dibagi menjadi dua yaitu Fisika dan Biologi. Materi dalam Rencana Pembelajaran yang diprioritaskan adalah materi yang mampu mengeksplorasi alam di sekitar sekolah. Untuk pelaksanaan pembelajaran, metode yang digunakan sebagian besar adalah diskusi dan ekperimen dimana pelaksanaannya didominasi di luar kelas (outdoor) terutama alam di sekitar sekolah. Penilaian IPA mencakup ulangan harian, penilaian kinerja, Ujian Tengah Semester (UTS) dan Ujian Kenaikan Kelas (UKK). Di Sekolah Alam, terdapat dua jenis rapor yaitu rapor nilai dan rapor dalam bentuk deskriptif yang disebut groovy. Dalam groovy terdapat tiga kriteria perkembangan siswa yaitu belum tampak, berkembang, dan mandiri. ;---This study is motivated by the fact showing the environmental concern is decreasing. Hence, it is necessary to provide an education system which is environmental friendly, such as in Sekolah Alam (Nature School). Unite with the nature is a concept of Sekolah Alam, so that in the learning activity at this school is emphasize to natural based learning and experience. Science as a learning subject is related to phenomenon and object in nature. The focus of this study are plan, implementation and evaluation on science subject in junior high school at Sekolah Alam Bandung. The purpose of this study is to find out how the implementation of Science learning is based in the curriculum with the special characteristic of Sekolah Alam. This study used qualitative approach, with a case study method. The data collection techniques were documentation study, interview and observation. The result of the study showed that Science lesson plan was begun by establishing the lesson plan dividing Science subject into two subjects, Physics and Biology. Materials in lesson plan prioritized are those which can explore the nature around the school. For the implementation, the methods mainly used were discussion and experiment outside the classroom (outdoor), especially at the nature around school. Furthermore, Science assessment consists of daily test, performance assessment, midterm and final exam. In Sekolah Alam, there are two types of report namely score report and report in descriptive form called groovy. In groovy there are three categories of student development first is not appear, develop and autonomous

Influence of immediate postpartum contraception counseling on the rate of unintended pregnancy in primigravida: a randomized controlled study

Background: The current study aims to assess the influence of immediate postpartum counselling about effective contraceptive methods to be used by primigravida on the rate of unintended pregnancy during first 6 months post-partum.Methods: The study was a prospective randomized controlled trial for assessment the influence of immediate postpartum counseling about effective contraceptive methods to be used by primigravida on the rate of unintended pregnancy during first 6 months post-partum who delivered at the period between the 1st of December 2016 and 31st of December 2017. The study patients were randomly assigned into two groups: Group (A) were received counseling about contraceptive methods using illustrations through postpartum interview with the study researcher. Group (B) were not received any counseling about contraceptive methods. The primary outcome was the difference in the rate of unintended pregnancy in both groups.Results: No significant difference between both groups in preventing unintended pregnancy. In group (A): After 3 months postpartum 140 women (93.3%) were used the contraceptive method correctly. 10 women used method incorrectly and 2 of them get pregnant. After 6 months postpartum 8 women did not use any method but 134 women (95.7%) were correctly used the contraceptive method. In group (B): After 3 months postpartum 127 women (84.7%) were used the contraceptive method correctly. 23 women used method incorrectly and 4 of them get pregnant. After 6 months postpartum 1 woman did not use any method but 30 women (20.7%) were incorrectly used the contraceptive method.Conclusions: Immediate post-partum counseling about contraceptive methods is good tool to educate women who intend to have optimal inter–pregnancy period about the effective methods that suit them and when to initiate

Self-assembly of mechanoplasmonic bacterial cellulose-metal nanoparticle composites

Nanocomposites of metal nanoparticles (NPs) and bacterial nanocellulose (BC) enable fabrication of soft and biocompatible materials for optical, catalytic, electronic, and biomedical applications. Current BC-NP nanocomposites are typically prepared by in situ synthesis of the NPs or electrostatic adsorption of surface functionalized NPs, which limits possibilities to control and tune NP size, shape, concentration, and surface chemistry and influences the properties and performance of the materials. Here a self-assembly strategy is described for fabrication of complex and well-defined BC-NP composites using colloidal gold and silver NPs of different sizes, shapes, and concentrations. The self-assembly process results in nanocomposites with distinct biophysical and optical properties. In addition to antibacterial materials and materials with excellent senor performance, materials with unique mechanoplasmonic properties are developed. The homogenous incorporation of plasmonic gold NPs in the BC enables extensive modulation of the optical properties by mechanical stimuli. Compression gives rise to near-field coupling between adsorbed NPs, resulting in tunable spectral variations and enhanced broadband absorption that amplify both nonlinear optical and thermoplasmonic effects and enables novel biosensing strategies

Altered T-cell responses by the periodontal pathogen Porphyromonas gingivalis.

Several studies support an association between the chronic inflammatory diseases periodontitis and atherosclerosis with a crucial role for the periodontal pathogen Porphyromonas gingivalis. However, the interplay between this pathogen and the adaptive immune system, including T-cells, is sparsely investigated. Here we used Jurkat T-cells to determine the effects of P. gingivalis on T-cell-mediated adaptive immune responses. We show that viable P. gingivalis targets IL-2 expression at the protein level. Initial cellular events, including ROS production and [Ca(2+)](i), were elevated in response to P. gingivalis, but AP-1 and NF-κB activity dropped below basal levels and T-cells were unable to sustain stable IL-2 accumulation. IL-2 was partially restored by Leupeptin, but not by Cathepsin B Inhibitor, indicating an involvement of Rgp proteinases in the suppression of IL-2 accumulation. This was further confirmed by purified Rgp that caused a dose-dependent decrease in IL-2 levels. These results provide new insights of how this periodontal pathogen evades the host adaptive immune system by inhibiting IL-2 accumulation and thus attenuating T-cell proliferation and cellular communication