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1.
Int J Oral Maxillofac Surg ; 52(5): 604-612, 2023 May.
Article in English | MEDLINE | ID: mdl-36328864

ABSTRACT

The aim of this study was to determine whether the autogenous dentin graft (ADG) shows comparable results and similar clinical performance to other graft materials when utilized for implant placement. Four databases were searched, and controlled human studies that applied autogenous dentin for implant surgery, comparing it with other bone grafts, were included. Nine articles met the inclusion criteria, five of which were randomized controlled trials and were included in the meta-analysis. ADG showed equivalent primary and secondary implant stability when compared to Bio-Oss (primary: mean difference -0.74, 95% confidence interval (CI) - 3.36 to 1.88, P = 0.58; secondary: mean difference - 1.29, 95% CI - 5.69 to 3.11, P = 0.57). The standardized mean difference (SMD) of marginal bone loss at 6 months and at the final follow-up (18 months) showed the two grafts to be similar (6 months: SMD -0.26, 95% CI -0.64 to 0.12, P = 0.18; final follow-up: SMD -0.12, 95% CI -0.50 to 0.26, P = 0.53), and survival after immediate implant placement was the same in the two groups: 97.37% and 97.30%, respectively. Incidences of complications with the autogenous dentin particles or blocks were in line with those of Bio-Oss or autogenous bone blocks, respectively. This meta-analysis indicates that the autogenous dentin graft is an effective option for bone augmentation around dental implants, with acceptable implant stability, marginal bone loss, and incidences of complications and failure.


Subject(s)
Alveolar Ridge Augmentation , Dental Implants , Humans , Dental Implantation, Endosseous , Alveolar Ridge Augmentation/methods , Randomized Controlled Trials as Topic , Dentin
2.
Cells Tissues Organs ; 194(5): 382-405, 2011.
Article in English | MEDLINE | ID: mdl-21389671

ABSTRACT

BACKGROUND/AIMS: Tooth root cementum is sensitive to modulation of inorganic pyrophosphate (PP(i)), an inhibitor of hydroxyapatite precipitation. Factors increasing PP(i) include progressive ankylosis protein (ANK) and ectonucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) while tissue nonspecific alkaline phosphatase hydrolyzes PP(i). Studies here aimed to define the role of ANK in root and cementum by analyzing tooth development in Ank knock-out (KO) mice versus wild type. MATERIALS AND METHODS: Periodontal development in KO versus control mice was analyzed by histology, histomorphometry, immunohistochemistry, in situ hybridization, electron microscopy, and nanoindentation. Cementoblast cultures were used in vitro to provide mechanistic underpinnings for PP(i) modulation of cell function. RESULTS: Over the course of root development, Ank KO cervical cementum became 8- to 12-fold thicker than control cervical cementum. Periodontal ligament width was maintained and other dentoalveolar tissues, including apical cementum, were unaltered. Cervical cementum uncharacteristically included numerous cells, from rapid cementogenesis. Ank KO increased osteopontin and dentin matrix protein 1 gene and protein expression, and markedly increased NPP1 protein expression in cementoblasts but not in other cell types. Conditional ablation of Ank in joints and periodontia confirmed a local role for ANK in cementogenesis. In vitro studies employing cementoblasts indicated that Ank and Enpp1 mRNA levels increased in step with mineral nodule formation, supporting a role for these factors in regulation of cementum matrix mineralization. CONCLUSION: ANK, by modulating local PP(i), controls cervical cementum apposition and extracellular matrix. Loss of ANK created a local environment conducive to rapid cementogenesis; therefore, approaches modulating PP(i) in periodontal tissues have potential to promote cementum regeneration.


Subject(s)
Dental Cementum/metabolism , Extracellular Matrix/metabolism , Phosphate Transport Proteins/metabolism , Tooth/growth & development , Animals , Dental Cementum/ultrastructure , Extracellular Matrix/ultrastructure , Gene Expression Regulation, Developmental , Mice , Mice, Knockout , Phosphate Transport Proteins/genetics , Tooth/metabolism , Tooth/ultrastructure , Tooth Root/growth & development , Tooth Root/metabolism , Tooth Root/ultrastructure
3.
J Periodontol ; 80(8): 1348-54, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19656036

ABSTRACT

BACKGROUND: Cementogenesis is sensitive to altered local phosphate levels; thus, we hypothesized a cementum phenotype, likely of decreased formation, would be present in the teeth of X-linked hypophosphatemic (Hyp) mice. Mutations in the phosphate-regulating gene with homologies to endopeptidases on the X chromosome (Phex) cause X-linked hypophosphatemia, characterized by rickets, osteomalacia, and hypomineralized dentin formation, a phenotype recapitulated in the Hyp mouse homolog. Here, we report a developmental study of tooth root formation in Hyp mouse molars, focusing on dentin and cementum. METHODS: Light and transmission electron microscopy were used to study molar tissues from wild-type (WT) and Hyp mice. Demineralized and hematoxylin and eosin-stained tissues at developmental stages 23 to 96 days postcoital (dpc) were examined by light microscopy. Immunohistochemistry methods were used to detect bone sialoprotein (BSP) distribution in Hyp and WT mouse molar tissues, and transmission electron microscopy was used to study similar molar tissues in the non-demineralized state. RESULTS: Dentin in Hyp mice exhibited mineralization defects by 33 dpc, as expected, but this defect was partially corrected by 96 dpc. In support of our hypothesis, a cementum phenotype was detected using a combination of immunohistochemistry and transmission electron microscopy, which included thinner BSP-positive staining within the cementum, discontinuous mineralization, and a globular appearance compared to WT controls. CONCLUSION: Mutations in the phosphate-regulating Phex gene of the Hyp mouse resulted in defective cementum development.


Subject(s)
Cementogenesis/genetics , Dental Cementum/abnormalities , Familial Hypophosphatemic Rickets/pathology , Genetic Diseases, X-Linked , Animals , Dental Cementum/pathology , Dentin/abnormalities , Dentin/pathology , Dentinogenesis/genetics , Female , Gestational Age , Immunohistochemistry , Integrin-Binding Sialoprotein , Male , Mice , Mice, Mutant Strains , Microscopy, Electron, Transmission , Molar/abnormalities , Molar/pathology , Mutation/genetics , Odontogenesis/genetics , PHEX Phosphate Regulating Neutral Endopeptidase/genetics , Phenotype , Sialoglycoproteins/analysis , Tooth Calcification/genetics , Tooth Germ/abnormalities , Tooth Germ/pathology , Tooth Root/abnormalities , Tooth Root/pathology
4.
J Biomed Mater Res A ; 79(4): 1015-22, 2006 Dec 15.
Article in English | MEDLINE | ID: mdl-17001657

ABSTRACT

Several molecules such as bone morphogenetic protein-7, bone sialoprotein (BSP), or amelogenin gene splice products (A+4 or A-4) have been shown to induce reparative dentin formation in a rat model. However, at the moment, the origin and the mechanism of differentiation of the pulp cells stimulated by the bioactive molecules remain poorly understood. The present investigation was undertaken to validate an ectopic oral mucosal mouse model to evaluate the effects of amelogenin gene splice product implantation in a non-mineralizing tissue. Agarose beads, alone or coated with amelogenin gene splice products, were implanted in the mucosa of the cheeks in mouse. An immunohistochemical characterization of the recruited cells was undertaken for 3 days, 8 days, and 30 days after the implantation. The results showed that the implantation of agarose beads in mucosa induced the recruitment of inflammatory CD45 positive cells. When the beads were coated with amelogenin gene splice products (A+4 or A-4), the expression of osteo-chondrogenic markers (RP59, Sox9, or BSP) was also observed. However, no mineralization nodule was observed, even after 30 days of implantation. The present investigation suggests that amelognin gene splice products have the capacity of recruiting among inflammatory cell mesenchymal progenitors that eventually differentiate into osteo-chondrogenic cells. Altogether, the results obtained in the pulp model and the present data suggest the existence of different pathways of cell recruitment and differentiation in different cellular environments.


Subject(s)
Absorbable Implants , Amelogenin , Cell Differentiation , Dental Pulp/metabolism , Leukocyte Common Antigens/metabolism , Mesenchymal Stem Cells/metabolism , Alternative Splicing , Amelogenin/metabolism , Animals , Antigens, Differentiation/biosynthesis , Bone Morphogenetic Protein 7 , Bone Morphogenetic Proteins/metabolism , Delayed-Action Preparations/metabolism , Delayed-Action Preparations/pharmacology , Dental Pulp/ultrastructure , Male , Mesenchymal Stem Cells/ultrastructure , Mice , Mouth Mucosa/metabolism , Mouth Mucosa/ultrastructure , Protein Isoforms/metabolism , Rats , Transforming Growth Factor beta/metabolism
5.
J Women High Educ ; 9(2): 169-189, 2016.
Article in English | MEDLINE | ID: mdl-28239435

ABSTRACT

Academic contrapower harassment (ACPH) occurs when someone with seemingly less power in an educational setting (e.g., a student) harasses someone more powerful (e.g., a professor). A representative sample of 289 professors from U.S. institutions of higher education described their worst incident with ACPH. Open-ended responses were coded using a keyword text analysis. Compared to the experiences of men faculty, women faculty reported that students were more likely to challenge their authority, argue or refuse to follow course policies, and exhibit disrespectful or disruptive behaviors. Although sexual harassment was uncommon, men faculty were more likely than women faculty to recount such incidents. Women faculty reported significantly more negative outcomes as a result of ACPH (e.g., anxiety, stress-related illness, difficulty concentrating, wanting to quit) than men faculty, and negative outcomes were most likely to result from ACPH involving intimidation, threats, or bullying from students. Implications for the prevention and reporting of ACPH are discussed.

6.
Bone Marrow Transplant ; 29 Suppl 1: S14-7, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11840156

ABSTRACT

The long median survival time of patients with follicular non-Hodgkin's lymphoma (NHL), means that the efficacy of new treatments are difficult to assess in the short term. Bcl-2 is an inhibitor of apoptosis and overexpression of the bcl-2 gene in the blood or bone marrow is a feature in up to 85% of patients with follicular NHL. Levels of bcl-2(+) cells in the peripheral blood or bone marrow therefore are a useful measure of disease status in such patients and can be detected by polymerase chain reaction (PCR). Complete bcl-2 clearance from the bone marrow (molecular remission) following autologous stem cell transplant (ASCT) for follicular NHL is considered to be an important prognostic factor for disease-free survival. Tumour cell contamination of the stem cell grafts used in ASCT is commonly associated with relapse. This can be addressed by purging the stem cell harvest prior to transplantation. Various methods of in vitro purging after stem cell collection have been shown to reduce the level of contamination but yield is invariably reduced and grafts remain bcl-2 positive. However, in vivo purging with rituximab during the process of collection has been used to obtain bcl-2-negative stem cell harvests without compromising the yield. Rituximab is a monoclonal antibody licensed for treatment of relapsed and refractory low-grade or follicular NHL. Rituximab targets the CD20 antigen, which is found on cells of the B cell lineage. When used for in vivo purging it depletes the peripheral blood of CD20-positive cells and prevents contamination by lymphoma cells. Molecular remission, as measured by bone-marrow bcl-2 clearance, has been achieved in 7/7 patients with follicular NHL at 1 year after treatment with ASCT using rituximab as an 'in vivopurse', followed by rituximab maintenance. Early clinical outcomes are also encouraging.


Subject(s)
Lymphoma, Follicular/pathology , Proto-Oncogene Proteins c-bcl-2/analysis , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Murine-Derived , Bone Marrow/chemistry , Bone Marrow/pathology , Bone Marrow Purging/methods , Humans , Lymphoma, Follicular/therapy , Rituximab , Stem Cell Transplantation/methods , Treatment Outcome
7.
Compend Contin Educ Dent ; 18(4): 384, 386-8, 390, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9452546

ABSTRACT

This article presents a clinical report of the prosthodontic treatment of a patient with a partially edentulous mandible. Osseointegrated titanium implants and resilient attachments for overdentures were used to retain and stabilize a mandibular overdenture that restored the patient's occlusion. This provided a simple and economical solution to retention and stability problems for a patient with a partially edentulous mandible.


Subject(s)
Dental Implantation, Endosseous/methods , Denture, Overlay , Jaw, Edentulous, Partially/therapy , Aged , Aged, 80 and over , Dental Abutments , Dental Implantation, Endosseous/instrumentation , Denture Design , Humans , Jaw, Edentulous, Partially/diagnostic imaging , Male , Mandible , Radiography, Panoramic
8.
Compend Contin Educ Dent ; 17(5): 504-7, 1996 May.
Article in English | MEDLINE | ID: mdl-9051947

ABSTRACT

The restoration of a patient's edentulous area with a three-unit fixed partial denture is described. The denture consisted of an etched-metal bonded retainer and metal ceramic pontic with a nonrigid connector in combination with a conventional inlay retainer. The incorporation of a nonrigid connector permitted the use of dissimilar metals and cements with retainers of different retention potentials. This technique provides minimal reduction of tooth structure with supragingival margins for improved periodontal health.


Subject(s)
Denture Design , Denture, Partial, Fixed , Jaw, Edentulous, Partially/therapy , Adult , Female , Humans , Mandible
9.
J Pediatr Surg ; 48(4): 730-7, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23583126

ABSTRACT

OBJECTIVE: Determine predictors of neurocognitive outcome in early school age congenital diaphragmatic hernia (CDH) survivors. STUDY DESIGN: Prospective study of infants with CDH at Duke University Medical Center. Neurocognitive delay (NCD) at school age (4 to 7years) was defined as a score<80 in any of the following areas: Verbal Scale IQ, Performance Scale IQ, Expressive Language, or Receptive Language. Logistic regression, Fisher's exact, and the Wilcoxon rank sum test were used to examine the relationship between NCD at early school age and 6 demographic and 18 medical variables. RESULTS: Of 43 infants with CDH, twenty seven (63%) survived to hospital discharge, and 16 (59%) returned for school age testing at a median age of 4.9years. Seven (44%) of the children evaluated had NCD. Patch repair (p=0.01), extracorporeal membrane oxygenation (ECMO; p=0.02), days on ECMO (p=0.01), days of mechanical ventilation (p=0.049), and post-operative use of inhaled nitric oxide (p=0.02) were found to be associated with NCD at early school age. CONCLUSIONS: CDH survivors are at risk for neurocognitive delay persisting into school age. Perinatal factors such as patch repair and ECMO treatment may aid in identifying CDH survivors at high risk for continued learning difficulties throughout childhood.


Subject(s)
Cognition Disorders/etiology , Hernias, Diaphragmatic, Congenital , Child , Child, Preschool , Cognition Disorders/diagnosis , Extracorporeal Membrane Oxygenation , Female , Hernia, Diaphragmatic/complications , Hernia, Diaphragmatic/surgery , Humans , Logistic Models , Male , Nitric Oxide/administration & dosage , Prospective Studies , Respiration, Artificial , Risk Factors , Statistics, Nonparametric , Survivors
10.
Anat Rec (Hoboken) ; 293(7): 1214-26, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20583265

ABSTRACT

Fibroblast growth factor-23 (FGF23) is a hormone that modulates circulating phosphate (P(i)) levels by controlling P(i) reabsorption from the kidneys. When FGF23 levels are deficient, as in tumoral calcinosis patients, hyperphosphatemia ensues. We show here in a murine model that Fgf23 ablation disrupted morphology and protein expression within the dentoalveolar complex. Ectopic matrix formation in pulp chambers, odontoblast layer disruption, narrowing of periodontal ligament space, and alteration of cementum structure were observed in histological and electron microscopy sections. Because serum P(i) levels are dramatically elevated in Fgf23(-/-), we assayed for apoptosis and expression of members from the small integrin-binding ligand, N-linked glycoprotein (SIBLING) family, both of which are sensitive to elevated P(i) in vitro. Unlike X-linked hypophosphatemic (Hyp) and wild-type (WT) specimens, numerous apoptotic osteocytes and osteoblasts were detected in Fgf23(-/-) specimens. Further, in comparison to Hyp and WT samples, decreased bone sialoprotein and elevated dentin matrix protein-1 protein levels were observed in cementum of Fgf23(-/-) mice. Additional dentin-associated proteins, such as dentin sialoprotein and dentin phosphoprotein, exhibited altered localization in both Fgf23(-/-) and Hyp samples. Based on these results, we propose that FGF23 and (P(i)) homeostasis play a significant role in maintenance of the dentoalveolar complex.


Subject(s)
Alveolar Process/pathology , Fibroblast Growth Factors/genetics , Hyperphosphatemia/pathology , Animals , Extracellular Matrix Proteins/metabolism , Familial Hypophosphatemic Rickets/genetics , Familial Hypophosphatemic Rickets/metabolism , Fibroblast Growth Factor-23 , Genetic Diseases, X-Linked , Humans , Hyperphosphatemia/genetics , Hyperphosphatemia/metabolism , Mice , Mice, Knockout , Osteocytes/metabolism , Phosphates/metabolism
12.
Body Image ; 6(4): 292-8, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19674946

ABSTRACT

Fat talk, dialogues among women involving negative body-focused discussions, was studied as a function of conformity and social likeability through the use of four vignettes depicting young women in conversation. Using a 2 (body presentation style of the group: negative or positive)x2 (body presentation style of the target, Jenny: negative or positive) factorial design, 215 college women (92.1% non-Hispanic Caucasian) read one of four vignettes in a classroom setting and made ratings on a social likeability scale. Participants' personal ratings of Jenny's likeability were higher when she spoke positively about her body, whereas they expected the other group members in the vignette to like Jenny more when she conformed to the group's body presentation style. This study is the first to support two competing norms for women's body image-the existing norm to fat talk versus a newly documented norm that some women like others who express body acceptance.


Subject(s)
Body Image , Self Disclosure , Social Conformity , Social Desirability , Adolescent , Body Weight , Female , Gender Identity , Humans , Social Environment , Students , Surveys and Questionnaires , Universities , Young Adult
13.
J Dent Res ; 88(4): 333-8, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19407153

ABSTRACT

TGF-beta1 exerts diverse functions in tooth development and tissue repair, but its role in microbial defenses of the tooth is not well-understood. Odontoblasts extending their cellular processes into the dentin are the first cells to recognize signals from TGF-beta1 and bacteria in carious dentin. This study aimed to determine the role of TGF-beta1 in modulating odontoblast responses to oral bacteria. We show that these responses depend upon the expression levels of microbial recognition receptors TLR2 and TLR4 on the cell surface. Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum activated both TLRs, but TLR4 played a greater role. Lack of cell-surface TLR2 was associated with poor response to Streptococcus mutans, Enterococcus faecalis, and Lactobacillus casei. TGF-beta1 inhibited TLR2 and TLR4 expression and attenuated odontoblast responses. Our findings suggest that the balance between TLR-mediated inflammation and TGF-beta1 anti-inflammatory activity plays an important role in pulpal inflammation.


Subject(s)
Dental Caries/immunology , Odontoblasts/immunology , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Transforming Growth Factor beta1/metabolism , Clone Cells , Dental Caries/etiology , Dental Caries/microbiology , Gram-Negative Bacterial Infections/complications , Gram-Negative Bacterial Infections/immunology , Gram-Positive Bacterial Infections/complications , Gram-Positive Bacterial Infections/immunology , Humans , Odontoblasts/cytology , Odontoblasts/metabolism , Pulpitis/etiology , Pulpitis/immunology , Pulpitis/microbiology , RNA Interference , RNA, Small Interfering/physiology , Regression Analysis , Signal Transduction/immunology , Signal Transduction/physiology
14.
Am J Dermatopathol ; 18(1): 70-2, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8721594

ABSTRACT

Sparganosis is an infection caused by migrating larvae of the cestode genus Spirometra. There have been approximately 62 cases of sparganosis reported in the United States. Although a subcutaneous mass is the most common manifestation, sparganosis is not well-described in the dermatology literature. We present a case of cutaneous sparganosis in a 52-year-old Filipino American woman. Histologically, the sections showed a granulomatous panniculitis and dermatitis containing a section of a sparganum. A transverse section of an intact sparganum reveals an eosinophilic cuticle, loose stroma, calcareous bodies, and smooth muscle fibers.


Subject(s)
Skin Diseases/pathology , Skin Diseases/parasitology , Sparganosis/pathology , Sparganosis/parasitology , Female , Humans , Middle Aged
15.
Air Med J ; 17(4): 169-73, 1998.
Article in English | MEDLINE | ID: mdl-10185099

ABSTRACT

INTRODUCTION: A significant portion of the Air Med Team (AMT) flight missions involves interfacility transport of the ill or injured to receiving facilities with comprehensive resources available for their care. In an effort to help meet the psychologic needs of our patients and their families, AMT developed a Family Member Ride-Along program that allows family members or significant others to accompany patients during interfacility transport. The purpose of this study was to evaluate the ride-along program from the perspective of the family member passenger (FMP) who has accompanied a patient during transport. METHODS: Thirty-one family member ride-alongs responded to a 10-item questionnaire using a scaled response. Questions were designed to evaluate the benefit of the ride-along program to patients and family members from the FMP perspective. RESULTS: All FMPs surveyed thought the program was beneficial to either themselves or the patients. Several benefits described by FMPs included the ability to offer emotional support to the patient, provide patient information to receiving physicians, and sign releases for medical treatment. During interfacility transports, FMPs did not hinder either patient care or transport safety. CONCLUSION: Our study shows that allowing FMPs to accompany patients during transport benefits both patients and family members.


Subject(s)
Air Ambulances , Family , Transportation of Patients , Air Ambulances/organization & administration , California , Evaluation Studies as Topic , Program Development , Surveys and Questionnaires , Transportation of Patients/organization & administration , Humans
16.
Br J Cancer ; 89(3): 482-6, 2003 Aug 04.
Article in English | MEDLINE | ID: mdl-12888816

ABSTRACT

A total of 10-40% of patients with Hodgkin's disease relapse following initial curative therapy. Intensive follow-up is resource intensive and may identify false relapses. We performed a retrospective review of all patients with Hodgkin's disease treated at our centre between 1990 and 1999 to evaluate the utility of the components of follow-up. A total of 107 patients met the inclusion and exclusion criteria. The median age was 33 years and the median duration of follow-up 38 months. The total number of follow-up visits was 1209 and total number of CT scans 283. There were 109 suspected relapses of which 22 proved to be true relapses. Of the latter, 14 were identified clinically, six radiologically and two via lab testing. The routine CT scan detected only two relapses (9%), yet accounted for 29% of the total follow-up costs. Based on data from our centre, the cost per true relapse was $6000 US, 49% incurred by radiological tests. The majority of the cost of follow-up was incurred by routine follow-up (84%) as opposed to the investigation of suspected relapses (16%). We conclude that most true relapses are clinically symptomatic and that the routine CT is an expensive and inefficient mode of routine follow-up.


Subject(s)
Hodgkin Disease/diagnostic imaging , Hodgkin Disease/drug therapy , Neoplasm Recurrence, Local/diagnostic imaging , Tomography, X-Ray Computed/economics , Adolescent , Adult , Aged , Aged, 80 and over , Cost-Benefit Analysis , Female , Follow-Up Studies , Hodgkin Disease/economics , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed/standards
17.
Cancer Immunol Immunother ; 49(6): 285-95, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10946810

ABSTRACT

In order to develop immunotherapy strategies that are based on eliciting immune responsiveness to the self-antigen, human carcinoembryonic antigen (CEA), we examined whether cytotoxic T lymphocyte (CTL) activity against CEA could be elicited in CEA-transgenic and nontransgenic mice. CEA-transgenic [C57BL/ 6-TGN(CEAGe)18FJP] and nontransgenic mice were primed with CEA-transfected syngeneic fibroblasts in combination with Corynebacterium parvum. Spleen cells from immunized mice were cultured with irradiated syngeneic MC-38 colon carcinoma cells transfected with CEA (MC-38.CEA) as stimulators prior to the measurement of CTL activity. Primed nontransgenic spleen cells showed augmented CTL activity against MC-38.CEA cells as compared with control parental MC-38 cells, nontransfected or transfected with vector only. Moreover, primed CEA transgenic spleen cells showed augmented CTL activity against MC-38.CEA cells that was similar to that observed in nontransgenic mice. All CTL clones derived from either transgenic or nontransgenic mice showed cross-reactivity with MC-38 cells expressing the CEA-related antigen, nonspecific cross-reacting antigen, but not biliary glycoprotein. CEA-specific CTL clones were not identified. Adoptive transfer of cloned CTL resulted in inhibition of MC-38.CEA but not MC-38.BGP tumor growth. Tumor cures were elicited in mice treated with a combination of cloned CTL and cyclophosphamide. Histopathological examination of CEA-expressing colons from either immunized mice or recipients of cloned CTL did not reveal any autoimmune reactions. These studies demonstrate that CTL recognizing cross-reactive class I epitopes on the CEA molecule can be induced in transgenic mice. The expression of these epitopes on tumor cells creates effective targets for CTL in vivo without inducing adverse reactions in CEA-expressing normal tissues. Since anti-CEA CTL have been generated in humans, CEA-transgenic mice may be a useful model to study vaccines that are based on CTL effector mechanisms.


Subject(s)
Carcinoembryonic Antigen/physiology , Immunotherapy, Adoptive , Neoplasms, Experimental/therapy , T-Lymphocytes, Cytotoxic/immunology , Animals , Autoimmunity , Cell Line , Cloning, Molecular , Colonic Neoplasms/therapy , H-2 Antigens/physiology , Humans , Mice , Mice, Inbred C57BL , Mice, Transgenic
18.
J Prosthet Dent ; 73(4): 370-2, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7783016

ABSTRACT

A two-stage impression technique that uses polyvinyl siloxane and irreversible hydrocolloid in a custom impression tray is described. The technique records the tissues to be contacted by the facial prosthesis with minimal distortion with the patient in an upright position and facial musculature at rest. The procedure is simple, accurate, and it eliminates some of the shortcomings of other techniques.


Subject(s)
Alginates , Maxillofacial Prosthesis , Polyvinyls , Prosthesis Design , Siloxanes , Acrylic Resins/chemistry , Adhesives/chemistry , Alginates/chemistry , Calcium Sulfate , Humans , Polyvinyls/chemistry , Siloxanes/chemistry
19.
J Biol Chem ; 275(52): 41263-72, 2000 Dec 29.
Article in English | MEDLINE | ID: mdl-10998415

ABSTRACT

Low molecular mass amelogenin-related polypeptides extracted from mineralized dentin have the ability to affect the differentiation pathway of embryonic muscle fibroblasts in culture and lead to the formation of mineralized matrix in in vivo implants. The objective of the present study was to determine whether the bioactive peptides could have been amelogenin protein degradation products or specific amelogenin gene splice products. Thus, the splice products were prepared, and their activities were determined in vitro and in vivo. A rat incisor tooth odontoblast pulp cDNA library was screened using probes based on the peptide amino acid sequencing data. Two specific cDNAs comprised from amelogenin gene exons 2,3,4,5,6d,7 and 2,3,5,6d, 7 were identified. The corresponding recombinant proteins, designated r[A+4] (8.1 kDa) and r[A-4] (6.9 kDa), were produced. Both peptides enhanced in vitro sulfate incorporation into proteoglycan, the induction of type II collagen, and Sox9 or Cbfa1 mRNA expression. In vivo implant assays demonstrated implant mineralization accompanied by vascularization and the presence of the bone matrix proteins, BSP and BAG-75. We postulate that during tooth development these specific amelogenin gene splice products, [A+4] and [A-4], may have a role in preodontoblast maturation. The [A+4] and [A-4] may thus be tissue-specific epithelial mesenchymal signaling molecules.


Subject(s)
Dental Enamel Proteins/physiology , Dental Implantation , Amelogenin , Amino Acid Sequence , Animals , Base Sequence , Cells, Cultured , Collagen/genetics , Dental Enamel Proteins/genetics , Molecular Sequence Data , Odontogenesis , Polymerase Chain Reaction , RNA, Messenger/analysis , Rats , Rats, Long-Evans , Recombinant Proteins/pharmacology
20.
CMAJ ; 140(8): 957-8, 1989 Apr 15.
Article in English | MEDLINE | ID: mdl-2702535
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