The role of calcium in the organization of fibrillin microfibrils

AbstractThe microfibrillar glycoprotein fibrillin has a multidomain structure which contains forty-three epidermal growth factor-like motifs with calciumbinding consensus sequences. We have utilized intact microfibrils isolated from human dermal fibroblast cultures to investigate the putative influence of bound calcium on microfibrillar organization and integrity. Incubation with EDTA or EGTA rapidly resulted in gross disruption of microfibril morphology. The treatment induced disorganization of the interbead domains although the regular beaded arrangement was always apparent. These changes were readily reversible on replacing calcium, indicating that the treatment had not compromised microfibrillar integrity. The data localize calcium binding EGF-like repeats to the interbead domains and indicate that lateral packing of fibrillin monomers is calcium-dependent. This arrangement suggests how mutations in epidermal growth factor-like domains of fibrillin might cause the disruption in microfibril organization and interactions which underlies the clinical symptoms of some Marian syndrome patients

Vascular endothelial growth factor can signal through platelet-derived growth factor receptors

Vascular endothelial growth factor (VEGF-A) is a crucial stimulator of vascular cell migration and proliferation. Using bone marrow–derived human adult mesenchymal stem cells (MSCs) that did not express VEGF receptors, we provide evidence that VEGF-A can stimulate platelet-derived growth factor receptors (PDGFRs), thereby regulating MSC migration and proliferation. VEGF-A binds to both PDGFRα and PDGFRβ and induces tyrosine phosphorylation that, when inhibited, results in attenuation of VEGF-A–induced MSC migration and proliferation. This mechanism was also shown to mediate human dermal fibroblast (HDF) migration. VEGF-A/PDGFR signaling has the potential to regulate vascular cell recruitment and proliferation during tissue regeneration and disease

PENYULUHAN PENINGKATAN KUALITAS BELAJAR SISWA DALAM MENYONGSONG PEMBELAJARAN TATAP MUKA DI MASA PANDEMI DENGAN TETAP DISIPLIN DALAM MENERAPKAN PROTOKOL KESEHATAN DI YAYASAN PEMBANGUNAN MASYARAKAT SEJAHTERA (YPMS) DARUSSALAM KEDAUNG PAMULANG

Learning is actually through the interaction of teachers with students to transmit knowledge in a learning environment. However, the dynamics of learning in Indonesia are currently being disrupted by the Covid-19 outbreak, which makes students have to undergo online learning activities. Many students experience difficulties and lack of motivation to participate in learning during the pandemic. One of the efforts to overcome educational problems during the pandemic is through learning assistance activities which are part of the Tridharma Perguruan Tinggi. This program is expected to help elementary school children in overcoming existing problems, so that children can understand and be motivated during online learning. The method used in this activity is the lecture method, discussion, and assignment method. The success of this activity can be seen from the enthusiasm and enthusiasm of students in participating in learning mentoring activities. In addition, students also succeeded in answering questions related to the material discussed

MENINGKATKAN DISIPLIN DAN TANGGUNG JAWAB PESERTA DIDIK DI ERA REVOLUSI INDUSTRI 4.0

Pada PKM kali ini kami mengambil objek penelitian yakni peserta didik di Rumah Yatim Lembaga Amil Zakat Nasional.  Masalah yang diambil berasal dari kurangnya pengetahuan dan penerapan disiplin dan tanggung jawab para peserta didik. Program penyuluhan yang akan diberikan oleh narasumber yang ahli diharapkan mampu memberikan pengetahuan terkait permasalahan diatas. Program PKM ini diharapkan menjadi kesempatan bagi para peserta didik berdiskusi dengan narasumber terkait implementasi dan cara meningkatkan disiplin dan tanggung jawab. Tujuan dari Kegiatan Pengabdian Kepada Masyarakat adalah untuk melaksanakan salah satu TriDharma Perguruan Tinggi. Selain itu diharapkan dengan pengabdian kepada masyarakat tersebut keberadaan perguruan tinggi dapat memberikan kontribusi besar kepada pengembangan dan penerapan keilmuan kepada masyarakat. Metode kegiatan yang digunakan adalah kita mendatangi Rumah Yatim Lembaga Amil Zakat Nasional yang beralamat Jl. RE Martadinata No. 58 Pamulang, Kota Tangerang Selatan dan akan memberikan pelatihan disana pada tanggal 02-04 Juli 2020. Pelatihan ini bertujuan agar siswa dan siswi yang ada di Rumah Yatim dapat meningkatkan disiplin dan tanggung jawab peserta didik di era revolusi industri 4.0 seperti sekarang ini. Hasil pengabdian masyarakat yang diperoleh adalah bertambahnya keilmuan bagi para peserta didik di Rumah Yatim agar mereka memiliki pandangan yang baik tentang pentingnya meningkatkan disiplin dan tanggung jawab pada masa kini sebagai bekal mereka untuk kehidupan di masa yang akan datang. Ilmu yang diperoleh pada Pengabdian Masyarakat kali ini diharapkan mampu memberikan semangat baru bagi kita dalam menyampaikan materi dan motivasi serta berkontribusi bagi generasi muda, baik dilingkungan sekolah, kampus dan keluarga.Kata Kunci: Disiplin, Tanggung Jawab, Revolusi Industr

MENINGKATKAN MOTIVASI BELAJAR PESERTA DIDIK DIRUMAH MASING-MASING SELAMA MASA PANDEMIC COVID-19 PADA YPMS DARUSSALAM KEDAUNG PAMULANG

Tujuan dari kegiatan Pengabdian Kepada Masyarakat ini adalah untuk melaksanakan salah satu Tri Dharma Perguruan Tinggi dan tujuan utamanya adalah untuk memberikan gambaran strategi yang dapat dilakukan dalam upaya menumbuhkan motivasi belajar para peserta didik saat ini, khususnya peserta didik pada jenjang SD, SMP Dan SMU. Selain itu diharapkan dengan pengabdian kepada masyarakat ini keberadaan perguruan tinggi dapat memberikan kontribusi besar kepada pengembangan dan penerapan keilmuan kepada masyarakat. Metode yang kegiatan yang dilaksanakan adalah kami mendatangi langsung ke lokasi PKM yaitu di YPMS Darussalam Kedaung Pamulang yang beralamat di Jl. Masjid Darussalam 40 RT 009/04 Kedaung, Pamulang, Tangerang Selatan 15413. Hasil pengabdian kepada masyarakat yang diperoleh yakni bertambahnya dorongan motivasi peserta didik untuk belajar di rumah masing-masing selama masa pandemic Covid-19 ini dan bertambahnya keilmuan peserta didik di YPMS Darussalam Kedaung Pamulang agar mereka memiliki cara pandang yang baik tentang pentingnya meningkatkan dan membangun motivasi diri untuk belajar lebih baik lagi dan belajar bertanggung jawab pada masa kini sebagai bekal mereka untuk kehidupan di amsa yang akan dating. Ilmu yang didapatkan pada Pengabdian Kepada Masyarakat kali ini diharapkan mampu memberikan semangat baru bagi dosen dalam upaya mengembangkan diri memberikan pengarahan, penyampaian materi dan motivasi serta berkontribusi bagi generasi muda baik di dalam lingkungan sekolah, kampus, keluarga dan masyarakat secara luas

Fibrillin-Rich Microfibrils are Reduced in Photoaged Skin. Distribution at the Dermal–Epidermal Junction

Chronic sun exposure results in photoaged skin with deep coarse wrinkles and loss of elasticity. We have examined the distribution and abundance of fibrillin-rich microfibrils, key structural components of the elastic fiber network, in photoaged and photoprotected skin. Punch biopsies taken from photoaged forearm and from photoprotected hip and upper inner arm of 16 subjects with a clinical range of photoaging were examined for fibrillin-1 and fibrillin-2 expression and microfibril distribution. In situ hybridization revealed decreased fibrillin-1 mRNA but unchanged fibrillin-2 mRNA levels in severely photoaged forearm biopsies relative to photoprotected dermal sites. An immunohistochemical approach demonstrated that microfibrils at the dermal–epidermal junction were significantly reduced in moderate to severely photoaged forearm skin. Confocal microscopy revealed that the papillary dermal microfibrillar network was truncated and depleted in photoaged skin. These studies highlight that the fibrillin-rich microfibrillar network associated with the upper dermis undergoes extensive remodeling following solar irradiation. These changes may contribute to the clinical features of photoaging, such as wrinkle formation and loss of elasticity

Fibrillin-1 regulates the bioavailability of TGFβ1

We have discovered that fibrillin-1, which forms extracellular microfibrils, can regulate the bioavailability of transforming growth factor (TGF) β1, a powerful cytokine that modulates cell survival and phenotype. Altered TGFβ signaling is a major contributor to the pathology of Marfan syndrome (MFS) and related diseases. In the presence of cell layer extracellular matrix, a fibrillin-1 sequence encoded by exons 44–49 releases endogenous TGFβ1, thereby stimulating TGFβ receptor–mediated Smad2 signaling. This altered TGFβ1 bioavailability does not require intact cells, proteolysis, or the altered expression of TGFβ1 or its receptors. Mass spectrometry revealed that a fibrillin-1 fragment containing the TGFβ1-releasing sequence specifically associates with full-length fibrillin-1 in cell layers. Solid-phase and BIAcore binding studies showed that this fragment interacts strongly and specifically with N-terminal fibrillin-1, thereby inhibiting the association of C-terminal latent TGFβ-binding protein 1 (a component of the large latent complex [LLC]) with N-terminal fibrillin-1. By releasing LLC from microfibrils, the fibrillin-1 sequence encoded by exons 44–49 can contribute to MFS and related diseases

Cell-matrix biology in vascular tissue engineering

We are developing biocompatible small-calibre vascular substitutes based on polymeric scaffolds that incorporate cell-matrix signals to enhance vascular cell attachment and function. Our graft scaffold comprises an outer electrostatically spun porous polyurethane layer seeded with smooth muscle cells, and a luminal polycaprolactone layer for endothelial cell attachment. Vascular cell adhesion properties of three vascular elastic fibre molecules, tropoelastin, fibrillin-1 and fibulin-5, have been defined, and adhesion fragments optimized. These fragments are being used to coat the scaffolds to enhance luminal endothelial cell attachment, and to regulate smooth muscle cell attachment and function. Tropoelastin-based cell seeding materials are also being developed. In this way, vascular cell-matrix biology is enhancing graft design

The tight skin mouse: demonstration of mutant fibrillin-1 production and assembly into abnormal microfibrils

Mice carrying the Tight skin (Tsk) mutation harbor a genomic duplication within the fibrillin-1 (Fbn 1) gene that results in a larger than normal in-frame Fbn 1 transcript. In this study, the consequences of the Tsk mutation for fibrillin-containing microfibrils have been examined. Dermal fibroblasts from Tsk/+ mice synthesized and secreted both normal fibrillin (approximately 330 kD) and the mutant oversized Tsk fibrillin-1 (approximately 450 kD) in comparable amounts, and Tsk fibrillin-1 was stably incorporated into cell layers. Immunohistochemical and ultrastructural analyses of normal and Tsk/+ mouse skin highlighted differences in the gross organization and distribution of microfibrillar arrays. Rotary shadowing of high Mr preparations from Tsk/+ skin demonstrated the presence of abundant beaded microfibrils. Some of these had normal morphology and periodicity, but others were distinguished by diffuse interbeads, longer periodicity, and tendency to aggregate. The presence of a structurally abnormal population of microfibrils in Tsk/+ skin was unequivocally demonstrated after calcium chelation and in denaturating conditions. Scanning transmission electron microscopy highlighted the presence of more mass in Tsk/+ skin microfibrils than in normal mice skin microfibrils. These data indicate that Tsk fibrillin-1 polymerizes and becomes incorporated into a discrete population of beaded microfibrils with altered molecular organization

Evaluation of seven commercial African swine fever virus detection kits and three Taq polymerases on 300 well-characterized field samples

peer reviewedAfrican swine fever virus (ASFV) is a complex double stranded DNA virus, responsible for a highly infectious and fatal disease in pigs and boars and for important deterioration of animal welfare. Over the last decade, the disease spread to several European and Asian countries causing unprecedented dramatic economic losses in pig industry. In the absence of a vaccine, affected countries rely on trustful diagnostic tests and adapted testing policies to set up control programs to fight against the disease. In this study, we evaluated the sensitivity and specificity of seven commercially available ASFV real-time PCR detection kits and three Taq polymerases on 300 well-characterized wild boar samples collected in Belgium during the 2018–2019 outbreak. This study confirms that all commercial kits and two Taq polymerases are suitable for ASFV detection in diagnostic laboratories. Furthermore, the use of endogenous controls is emphasized when testing field samples harvested on carcasses in an advanced stage of decomposition, in order to avoid false negative results. © 2020 Elsevier B.V