The Role of Neurotrophic Factors in Dental Pulp Stem Cell

Objectives: The objective of the study is to investigate the role of neurotrophic factors in the DPSCs mediated tissue regeneration. Methods: Human DPSCs cells were gift from Dr. Songtao Shi, Chair and Professor Department of Anatomy & Cell Biology, University of Pennsylvania School of Dental Medicine DPSCs mRNA was extracted from samples of five different patients, and reverse transcripted into cDNA. Primer sequences were designed with Primer3web online software. Quantitative PCR was performed on the cDNA samples using a 7900HT detection system (Applied Biosystems). All PCR reactions were carried out in triplicate. Quantification of the samples was calculated with the threshold cycle by ΔΔCt method. Immunofluorescent staining images were acquired using a Leica TCS SPE confocal microscope. Scratch assay images were acquired using a Leica DMiL inverted microscope. Results: The expression of the neurotrophic family members and the corresponding receptors in the DPSC were determined using quantitative PCR. Human DPSCs cells express high level of GDNF family of ligands PSPN and the corresponding receptor GFRa4. Preliminary data indicated that neurotrophic factor PSPN has a dose dependent effect on the DPSCs migration in vitro. Conclusions: Neurotrophic factors may promote DPSCs regeneration by promoting stem cells migration to the damaged pulp. This work will be important to understand the molecular mechanism of the dental pulp mediated tissue regeneration. The future direction is to investigate the effect of different neurotrophic factors on DPSCs behavior, and the downstream signaling pathways involved in the process

Comparison of expression of the GDNF family neurotrophic factors in dental pulp stem cells with deciduous and adult teeth

The glial cell line-derived neurotrophic factor (GDNF) family has a role in neuron growth within the peripheral and central nervous systems. This makes it a potential therapeutic agent for neurological conditions like Parkinson’s disease and epilepsy. GDNF has also been implicated in murine odontogenesis. In permanent and deciduous human dental pulp stem cells, this study found that GDNF family members and receptors are expressed, indicating neurotrophic factors may play a role in dental pulp regeneration

Potential Ciliary Neurotrophic Factor Application in Dental Stem Cell Therapy

Neurotrophic factors have long been considered growth factors that promote survival and growth of various neuronal tissues. Recent studies showed that neurotrophic factors are also present in dental pulp and periodontal ligament. This paper reviews the literature about the ciliary neurotrophic factor (CNTF), a member of the neurotrophic factor family, and indicates the potential clinical application of CNTF in dental stem cell therapy

Paul Boghossian, La peur du savoir. Sur le relativisme et le constructivisme de la connaissance

Le postulat selon lequel « il n’existe tout simplement pas de "monde réel" à propos duquel on pourrait être objectif » (Grégory Derville, Les Cahiers du Journalisme, 6, 1999, p. 153) serait devenu aujourd’hui l’hypothèse la plus largement adoptée par les sciences sociales. L’ouvrage du philosophe américain Paul Boghossian vient à point nommé pour questionner le « consensus remarquable » (p. 1) qui semble s’être peu à peu installé autour du « constructivisme de la connaissance » – défendu nota..

Species of Yeast Identified in the Plaque of Healthy Patients versus Periodontal Patients

Although many study the human oral cavity for bacteria, different species of yeast that are also present are often overlooked. Therefore, the different strains of yeasts found in the mouth have not yet been identified. This study focuses on developing a PCR-based technique to identify species of yeast in the mouth. The relationship between the species of yeast found in patients with periodontal disease versus healthy patients was also analyzed

Neurotrophic factor GDNF promotes survival of salivary stem cells

Stem cell-based regenerative therapy is a promising treatment for head and neck cancer patients that suffer from chronic dry mouth (xerostomia) due to salivary gland injury from radiation therapy. Current xerostomia therapies only provide temporary symptom relief, while permanent restoration of salivary function is not currently feasible. Here, we identified and characterized a stem cell population from adult murine submandibular glands. Of the different cells isolated from the submandibular gland, this specific population, Lin-CD24+c-Kit+Sca1+, possessed the highest capacity for proliferation, self renewal, and differentiation during serial passage in vitro. Serial transplantations of this stem cell population into the submandibular gland of irradiated mice successfully restored saliva secretion and increased the number of functional acini. Gene-expression analysis revealed that glial cell line-derived neurotrophic factor (Gdnf) is highly expressed in Lin-CD24+c-Kit+Sca1+ stem cells. Furthermore, GDNF expression was upregulated upon radiation therapy in submandibular glands of both mice and humans. Administration of GDNF improved saliva production and enriched the number of functional acini in submandibular glands of irradiated animals and enhanced salisphere formation in cultured salivary stem cells, but did not accelerate growth of head and neck cancer cells. These data indicate that modulation of the GDNF pathway may have potential therapeutic benefit for management of radiation-induced xerostomia

Pengembangan Modul Intervensi Untuk Meningkatkan Resiliensi Pada Individu Yang Mengalami Perubahan Fisik Menjadi Penyandang Disabilitas

Penelitian ini bertujuan untuk menindaklanjuti temuan sebelumnya dengan mengembangkan modul intervensi secara terperinci, yang selanjutnya dapat digunakan sebagai panduan dalam membantu meningkatkan resiliensi individu yang mengalami Perubahan kondisi fisik menjadi penyandang disabilitas. Penulis menyusun serta merinci rancangan implementasi awal yang direkomendasikan oleh penelitian sebelumnya kedalam langkah-langkah yang lebih sistematis dan operasional hingga memperoleh hasil akhir berupa modul. Metode yang digunakan berbasis tahapan riset aksi, meskipun proses yang dilakukan hanya sampai pada langkah ketiga, yaitu Perumusan solusi dari persoalan yang diangkat. Partisipan terdiri dari delapan individu yang mengalami Perubahan kondisi menjadi penyandang disabilitas. Selain partisipan, empat orang psikolog juga dilibatkan dalam penelitian ini sebagai penelaah modul. Hasil penelitian ini berupa sebuah paket modul intervensi untuk peningkatan resiliensi melalui penguatan faktor protektif serta pengembangan strategi koping dan adaptasi pada individu yang mengalami Perubahan kondisi fisik menjadi penyandang disabilitas. Paket modul tersebut terdiri dari 5 sub-modul yang telah disusun sedemikian rupa untuk memudahkan pelaksanaannya, terdiri dari modul: (1) memperkuat dukungan keluarga terhadap penyandang disabilitas; (2) pendampingan awal penyandang disabilitas; (3) intervensi lanjut 1 (penguatan faktor protektif internal); (4) intervensi lanjut 2 (pengembangan strategi koping); dan (5) intervensi lanjut 3 (langkah adaptasi positif)

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead