RESUMEN
The dental follicle is an ectomesenchymal tissue surrounding the developing tooth germ. It is believed that this tissue contains stem cells and lineage committed progenitor cells or precursor cells (PCs) for cementoblasts, periodontal ligament cells, and osteoblasts. In this study, we report the isolation of PCs derived from dental follicle of human third molar teeth. These fibroblast-like, colony forming and plastic adherent cells expressed putative stem cell markers Notch-1 and Nestin. We compared gene expressions of PCs, human mesenchymal stem cells (hMSCs), periodontal ligament cells (PDL-cells) and osteoblasts (MG63) for delimitation of PCs. Interestingly, PCs expressed higher amounts of insulin-like growth factor-2 (IGF-2) transcripts than hMSCs. Differentiation capacity was demonstrated under in vitro conditions for PCs. Long-term cultures with dexamethasone produced compact calcified nodules or appeared as plain membrane structures of different dimensions consisting of a connective tissue like matrix encapsulated by a mesothelium-like cellular structure. PCs differentially express osteocalcin (OCN) and bone sialoprotein (BS) after transplantation in immunocompromised mice but without any sign of cementum or bone formation. Therefore, our results demonstrate that cultured PCs are unique undifferentiated lineage committed cells residing in the periodontium prior or during tooth eruption.
Asunto(s)
Técnicas de Cultivo de Célula/métodos , Saco Dental/patología , Tercer Molar/citología , Tercer Molar/patología , Adolescente , Adulto , Animales , Diferenciación Celular , Línea Celular , Linaje de la Célula , Membrana Celular/metabolismo , Cartilla de ADN/química , Humanos , Inmunohistoquímica , Inmunofenotipificación , Sialoproteína de Unión a Integrina , Proteínas de Filamentos Intermediarios/metabolismo , Mesodermo/citología , Ratones , Tercer Molar/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Nestina , Osteoblastos/citología , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Reacción en Cadena de la Polimerasa , ARN/metabolismo , ARN Mensajero/metabolismo , Receptor Notch1 , Receptores de Superficie Celular/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sialoglicoproteínas/metabolismo , Células Madre/citología , Factores de Tiempo , Diente/metabolismo , Factores de Transcripción/metabolismoRESUMEN
While central ports are located at the chest, peripheral ports (PP) are inserted at the patients' forearms. Two new PPs (Healthport miniMax((R)) and Bard Titan Low Profile Port) and two well-established types (Port-A-Cath((R)) P.A.S. Port and PeriPort(TM) peripheral access system) were tested. 125 patients were given the choice between PP and chest ports, and 100 of them chose PP. PP were inserted in patients suffering from gastrointestinal malignancies (n = 95), AIDS (n = 3) or Crohn's disease (n = 2). The first 30 patients were prospectively monitored by repeated color-coded duplex sonography examinations in order to evaluate clinically inapparent thromboses. Easy percutaneous needle puncture as early as 1 day after surgery was possible using innovative ports with large septa. The following complications arose during 12,688 catheter placement days: difficult implantation (n = 5), intolerable pain at the insertion site (n = 1), port erosion of the skin (n = 1), catheter leaks (n = 4), disconnection of the catheter from the port (n = 1), systemic infections (n = 4), local infections (n = 6) and symptomatic deep vein thrombosis (n = 8) despite anticoagulation in 1 of these. Only systemic infections and intolerable pain resulted in PP explantation (n = 5); other complications were easily dealt with. No serious or life-threatening complications occurred.
Asunto(s)
Antineoplásicos/administración & dosificación , Cateterismo Periférico/instrumentación , Catéteres de Permanencia , Neoplasias Gastrointestinales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Cateterismo Periférico/efectos adversos , Catéteres de Permanencia/efectos adversos , Diseño de Equipo , Femenino , Humanos , Incidencia , Infecciones/etiología , Masculino , Persona de Mediana Edad , Dolor/etiología , Cooperación del Paciente , Trombosis de la Vena/etiologíaRESUMEN
OBJECTIVE: In maxillofacial surgery considerable blood loss is not uncommon. However, the use of autologous blood collected from the site of surgery is controversial. METHODS: Bacterial contamination of blood collected for autologous retransfusion was studied by standard microbiological methods in 25 patients undergoing elective non-malignant maxillofacial surgery. Swabs were taken from the pharynx and from the collected blood before and after routine treatment. The autologous blood was not used for transfusion. Preoperative antibiotic treatment consisted in amoxicilline plus clavulanic acid. RESULTS: The blood prepared for retransfusion was free of bacteria in only one case, while 24 samples contained up to five different bacterial species including some strains not preexistent in the pharyngeal swabs. CONCLUSION: Blood collected from the site of operation is not suitable for retransfusion in maxillofacial surgery.
Asunto(s)
Pérdida de Sangre Quirúrgica , Transfusión de Sangre Autóloga/métodos , Procedimientos Quirúrgicos Orales , Adulto , Amoxicilina/uso terapéutico , Profilaxis Antibiótica , Bacterias/aislamiento & purificación , Ácido Clavulánico/uso terapéutico , Quimioterapia Combinada/uso terapéutico , Cara , Femenino , Humanos , Maxilares , Masculino , Boca , Faringe/microbiologíaRESUMEN
From 1985 to 1992 40 patients with large defects of the orbital wall were operated by reconstructive surgery. Defects were caused by trauma (35), facial cleft (3), tumor (1) and osteoradionecrosis (1). Small defects were covered with lyophilised dura mater or thin PDS-film, larger defects with autogenous or xenogenous cartilage, PDS-plates, ceramic plates or titanium micro mesh. After tumor surgery and osteoradionecrosis the orbital wall was reconstructed with free resp. microvascularised bone. In all cases a clear improvement of the initial position was possible. Dislocation of the zygomatic bone should be corrected by osteotomy in order to reconstruct as much as possible of the orbital wall with local bone.