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1.
Aust Dent J ; 67(3): 286-295, 2022 09.
Article in English | MEDLINE | ID: mdl-35170034

ABSTRACT

Macrodontia is a relatively uncommon dental anomaly and has often been reported to occur in association with other dental anomalies. Significant orthodontic and restorative challenges may arise in the management of patients with macrodont teeth. This case report demonstrates the opportune and carefully considered management of a patient presenting with both a macrodont and a supernumerary incisor tooth.


Subject(s)
Tooth Abnormalities , Tooth, Supernumerary , Humans , Incisor , Tooth, Supernumerary/complications , Tooth, Supernumerary/diagnostic imaging , Tooth, Supernumerary/surgery
2.
Aust Dent J ; 66(1): 96-104, 2021 03.
Article in English | MEDLINE | ID: mdl-32314367

ABSTRACT

Non-surgical camouflage orthodontic treatment can be effective for the management of carefully selected patients with mild to moderate Class III malocclusion. This case report demonstrates how a synergistic combination of camouflage orthodontic treatment and appropriate adjunctive restorative procedures can provide a pleasing treatment outcome for a patient with a significant skeletal Class III malocclusion and diminutive maxillary lateral incisors.


Subject(s)
Malocclusion, Angle Class III , Malocclusion , Adult , Cephalometry , Humans , Incisor , Malocclusion, Angle Class III/diagnostic imaging , Malocclusion, Angle Class III/therapy
3.
Aust Dent J ; 62(2): 233-240, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28100000

ABSTRACT

Transverse maxillary deficiency may be associated with dental crowding, compromised aesthetics and impaired function. Non-surgical correction of maxillary transverse deficiency through rapid maxillary expansion is routinely performed for young patients; however, surgical intervention is generally required for adults. An interdisciplinary treatment approach is necessary to achieve the desired treatment objectives for challenging cases. This case report demonstrates a pleasing treatment outcome for a patient with a severe maxillary transverse deficiency, significant crowding and extensive active caries.


Subject(s)
Dental Caries/surgery , Malocclusion/therapy , Maxilla/surgery , Orthodontics/methods , Palatal Expansion Technique , Cephalometry , Endodontics/methods , Female , Humans , Treatment Outcome , Young Adult
4.
J Colloid Interface Sci ; 282(1): 128-32, 2005 Feb 01.
Article in English | MEDLINE | ID: mdl-15576090

ABSTRACT

The oscillating drop/bubble technique is increasingly popular for measuring the interfacial dilatational properties of surfactant/polymer-laden fluid/fluid interfaces. A caveat of this technique, however, is that viscous forces are important at higher oscillation frequencies or fluid viscosities; these can affect determination of the interfacial tension. Here, we experimentally quantify the effect of viscous forces on the interfacial-tension measurement by oscillating 100 and 200 cSt poly(dimethylsiloxane) (PDMS) droplets in water at small amplitudes and frequencies ranging between 0.01 and 1 Hz. Due to viscous forces, the measured interfacial tension oscillates sinusoidally with the same frequency as the oscillation of the drop volume. The tension oscillation precedes that of the drop volume, and the amplitude varies linearly with Capillary number, Ca=DeltamuomegaDeltaV/gammaa(2), where Deltamu=mu(D)-mu is the difference between the bulk Newtonian viscosities of the drop and surrounding continuous fluid, omega is the oscillation frequency of the drop, DeltaV is the amplitude of volume oscillation, gamma is the equilibrium interfacial tension between the PDMS drop and water, and a is the radius of the capillary. A simplified model of a freely suspended spherical oscillating-drop well explains these observations. Viscous forces distort the drop shape at Ca>0.002, although this criterion is apparatus dependent.


Subject(s)
Models, Theoretical , Surface Tension , Rheology , Surface-Active Agents , Viscosity
5.
Infect Immun ; 67(11): 6181-6, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10531286

ABSTRACT

The permeability of the outer membrane (OM) to hydrophobic probes and its susceptibility to bactericidal cationic peptides were investigated for natural rough Brucella ovis and for mutant rough Brucella abortus strains. The OM of B. ovis displayed an abrupt and faster kinetic profile than rough B. abortus during the uptake of the hydrophobic probe N-phenyl-naphthylamine. B. ovis was more sensitive than rough B. abortus to the action of cationic peptides. Bactenecins 5 and 7 induced morphological alterations on the OMs of both rough Brucella strains. B. ovis lipopolysaccharide (LPS) captured considerably more polymyxin B than LPSs from both rough and smooth B. abortus strains. Polymyxin B, poly-L-lysine, and poly-L-ornithine produced a thick coating on the surfaces of both strains, which was more evident in B. ovis than in rough B. abortus. The distinct functional properties of the OMs of these two rough strains correlate with some structural differences of their OMs and with their different biological behaviors in animals and culture cells.


Subject(s)
Anti-Bacterial Agents/pharmacology , Brucella abortus/drug effects , Brucella/drug effects , Cell Membrane Permeability , Animals , Brucella/metabolism , Brucella/ultrastructure , Brucella abortus/metabolism , Brucella abortus/ultrastructure , Cell Membrane/drug effects , Lipopolysaccharides/metabolism , Microscopy, Electron , Peptides, Cyclic/pharmacology , Polymyxin B/metabolism
6.
J Biol Chem ; 274(16): 11046-52, 1999 Apr 16.
Article in English | MEDLINE | ID: mdl-10196187

ABSTRACT

The large clostridial cytotoxins (LCTs) constitute a group of high molecular weight clostridial cytotoxins that inactivate cellular small GTP-binding proteins. We demonstrate that a novel LCT (TcdB-1470) from Clostridium difficile strain 1470 is a functional hybrid between "reference" TcdB-10463 and Clostridium sordellii TcsL-1522. It bound to the same specific receptor as TcdB-10463 but glucosylated the same GTP-binding proteins as TcsL-1522. All three toxins had equal enzymatic potencies but were equally cytotoxic only when microinjected. When applied extracellularly TcdB-1470 and TcdB-10463 were considerably more potent cytotoxins than TcsL-1522. The small GTP-binding protein R-Ras was identified as a target for TcdB-1470 and also for TcsL-1522 but not for TcdB-10463. R-Ras is known to control integrin-extracellular matrix interactions from inside the cell. Its glucosylation may be a major determinant for the cell rounding and detachment induced by the two R-Ras-attacking toxins. In contrast, fibroblasts treated with TcdB-10463 were arborized and remained attached, with phosphotyrosine containing structures located at the cell-to-cell contacts and beta3-integrin remaining at the tips of cellular protrusions. These components were absent from cells treated with the R-Ras-inactivating toxins. The novel hybrid toxin will broaden the utility of the LCTs for clarifying the functions of several small GTPases, now including also R-Ras.


Subject(s)
Bacterial Toxins/metabolism , Clostridioides difficile/metabolism , Cytotoxins/metabolism , 3T3 Cells , Animals , Bacterial Toxins/pharmacology , Base Sequence , Cell Adhesion/drug effects , Cytotoxins/pharmacology , DNA Primers , Glycosylation , Mice , Microscopy, Electron, Scanning , Recombinant Fusion Proteins/metabolism
7.
Aust Orthod J ; 15(4): 214-8, 1999 Apr.
Article in English | MEDLINE | ID: mdl-11933355

ABSTRACT

The study models of 100 Grade Seven students were used to compare the Dental Aesthetic Index (DAI), the Dental Health Component (DHC) and the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN), and the Danish Ministry of Health (DMH) screening system. The basis for comparison was the agreed subjective assessment of two orthodontists for each subject. Disagreements between the subjective assessment and each screening method were further analysed in an attempt to identify the specific occlusal traits responsible for the disagreement. The DAI under-estimated treatment need in cases with displaced canine teeth, incisor crowding or rotations and increased overbite. The DAI over-estimated treatment need in cases with increased overjet in otherwise well-aligned arches. The DMH guidelines over-estimated treatment need in cases with increased overjet and crowded arches. The DHC was found to be over-sensitive in cases with increased overjet and contact point displacements greater than 2 mm. The AC under-estimated treatment need in cases with excessive overjet and buccally displaced canines, and over-estimated treatment need in cases with spaced arches and deep overbite.


Subject(s)
Mass Screening/methods , Needs Assessment , Orthodontics, Corrective , Adolescent , Child , Cuspid/pathology , Dental Arch/pathology , Esthetics, Dental , Female , Humans , Incisor/pathology , Male , Malocclusion/classification , Malocclusion/diagnosis , Models, Dental , Observer Variation , Queensland , Reproducibility of Results , Rotation , Statistics as Topic
8.
J Bacteriol ; 178(20): 5867-76, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8830680

ABSTRACT

A rough (R) Brucella abortus 45/20 mutant was more sensitive to the bactericidal activity of polymyxin B and lactoferricin B than was its smooth (S) counterpart but considerably more resistant than Salmonella montevideo. The outer membrane (OM) and isolated lipopolysaccharide (LPS) of S. montevideo showed a higher affinity for these cationic peptides than did the corresponding B. abortus OM and LPS. We took advantage of the moderate sensitivity of R B. abortus to cationic peptides to construct live R B. abortus-S-LPS chimeras to test the activities of polymyxin B, lactoferricin B, and EDTA. Homogeneous and abundant peripheral distribution of the heterologous S-LPS was observed on the surface of the chimeras, and this coating had no effect on the viability or morphology of the cells. When the heterologous LPS corresponded to the less sensitive bacterium S B. abortus S19, the chimeras were more resistant to cationic peptides; in contrast, when the S-LPS was from the more sensitive bacterium S. montevideo, the chimeras were more susceptible to the action of peptides and EDTA. A direct correlation between the amount of heterologous S-LPS on the surface of chimeric Brucella cells and peptide sensitivity was observed. Whereas the damage produced by polymyxin B in S. montevideo and B. abortus-S. montevideo S-LPS chimeras was manifested mainly as OM blebbing and inner membrane rolling, lactoferricin B caused inner membrane detachment, vacuolization, and the formation of internal electron-dense granules in these cells. Native S and R B. abortus strains were permeable to the hydrophobic probe N-phenyl-1-naphthylamine (NPN). In contrast, only reduced amounts of NPN partitioned into the OMs of the S. montevideo and B. abortus-S. montevideo S-LPS chimeras. Following peptide exposure, accelerated NPN uptake similar to that observed for S. montevideo was detected for the B. abortus-S. montevideo LPS chimeras. The partition of NPN into native or EDTA-, polymyxin B-, or lactoferricin B-treated LPS micelles of S. montevideo or B. abortus mimicked the effects observed with intact cells, and this was confirmed by using micelle hybrids of B. abortus and S. montevideo LPSs. The results showed that LPS is the main cause of B. abortus' resistance to bactericidal cationic peptides, the OM-disturbing action of divalent cationic chelants, and OM permeability to hydrophobic substances. It is proposed that these three features are related to the ability of Brucella bacteria to multiply within phagocytes.


Subject(s)
Anti-Bacterial Agents/pharmacology , Brucella abortus/drug effects , Lipopolysaccharides/metabolism , Salmonella/drug effects , Brucella abortus/genetics , Brucella abortus/ultrastructure , Cell Membrane/metabolism , Cell Membrane Permeability , Chimera , Dose-Response Relationship, Drug , Drug Resistance, Microbial , Edetic Acid/pharmacology , Fluorescent Dyes , Lactoferrin/analogs & derivatives , Lactoferrin/pharmacology , Micelles , Models, Molecular , Polymyxin B/pharmacology , Salmonella/genetics , Salmonella/ultrastructure
9.
Res Microbiol ; 146(7): 569-78, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8577998

ABSTRACT

This work demonstrates that Brucella lipopolysaccharide (LPS) preparations are a family of related molecules which display heterogeneity not only at the level of the O polysaccharide, but also at the core oligosaccharide and the lipid A. Sodium dodecyl sulphate/polyacrylamide gel electrophoresis and Western blotting showed that LPS from Brucella strains displayed molecular weight and antigenic heterogeneity. Smooth-type LPS (S-LPS) from B. abortus demonstrated three broad high-molecular-weight bands corresponding to S-LPS, and a low-molecular-weight band corresponding to O antigen lacking rough-type LPS (R-LPS). B. abortus R-LPS displayed four bands in increasing proportions as the molecular weight diminished. Immunodetection on high-performance thin-layer chromatography (HPTLC) with monoclonal antibodies (mAb) showed that R-LPS displayed three diffuse bands. HPTLC of O polysaccharide revealed two fast migrating bands recognized by antibodies. Gel chromatography and HPTLC analysis of core oligosaccharides from R-LPS demonstrated molecular weight heterogeneity as well as heterogeneous banding pattern, with no obvious correspondence between the two profiles. Immunodetection of lipid A on HPTLC plates revealed two major and three minor bands. Reactivity with mAbs suggested that regardless of the lipid A heterogeneity the basic structure of lipid A backbone is maintained.


Subject(s)
Brucella abortus/chemistry , Lipopolysaccharides/chemistry , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Electrophoresis, Polyacrylamide Gel , Immunoblotting , In Vitro Techniques , Lipopolysaccharides/isolation & purification
10.
Clin Diagn Lab Immunol ; 1(2): 206-13, 1994 Mar.
Article in English | MEDLINE | ID: mdl-7496947

ABSTRACT

Sera from Brucella abortus-infected and -vaccinated bovines recognized four lipopolysaccharide (LPS) determinants: two in the O-polysaccharide (A and C), one in the core oligosaccharide from rough Brucella LPS (R), and one in lipid A (LA). From 46 different hybridomas secreting monoclonal antibodies (MAbs) against various LPS moieties, 9 different specificities were identified. Two epitopes, A and C/Y, were present in the O-polysaccharide. Two epitopes were found in the core oligosaccharide (R1 and R2) of rough Brucella LPS. MAbs against R1 and R2 epitopes reacted against LPS from different rough Brucella species; however, MAbs directed to the R2 epitope also reacted against enterobacterial LPS from deep rough mutants. Three epitopes (LA1, LA2, and LA3) were located in the lipid A backbone. Different sets of MAbs recognized two epitopes in the lipid A-associated outer membrane protein (LAOmp3-1 and LAOmp3-2). LPS preparations from smooth brucellae had small amounts of rough-type LPS. Although LPS from rough brucellae did not show smooth-type LPS in western blots (immunoblots), two hybridomas generated from mice immunized with rough B. abortus produced antibodies against smooth B. abortus LPS. Results are discussed in relation to the structure and function of B. abortus LPS and to previous findings on the epitopic density of the molecule.


Subject(s)
Brucella abortus/immunology , Epitopes/immunology , Lipopolysaccharides/immunology , Animals , Antibodies, Bacterial/chemistry , Antibodies, Monoclonal/chemistry , Antigen-Antibody Reactions , Bacterial Outer Membrane Proteins/immunology , Blotting, Western , Brucella abortus/chemistry , Cattle , Epitopes/chemistry , Lipid A/immunology , Lipopolysaccharides/chemistry , Mice , Mice, Inbred BALB C , O Antigens/immunology , Oligosaccharides/immunology
11.
Infect Immun ; 60(4): 1699-702, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1548094

ABSTRACT

Both Brucella abortus lipopolysaccharide (LPS) and lipid A were low activators of nitroblue tetrazolium reduction and lysozyme release in human neutrophils. The stimulation was dose dependent and was higher in the presence of autologous plasma than in its absence. The comparison between Brucella LPS and lipid A versus Salmonella LPS revealed that at least 100 times more LPS and 1,000 times more lipid A of the former genus were required to induce significant nitroblue tetrazolium reduction and a corresponding lysozyme release in neutrophils. Low Brucella LPS-mediated superoxide and lysozyme production might contribute to the survival of these facultative intracellular bacteria in phagocytic cells.


Subject(s)
Brucella abortus/pathogenicity , Endotoxins , Lipopolysaccharides/immunology , Muramidase/metabolism , Neutrophils/drug effects , Oxygen Consumption/drug effects , Bacterial Toxins/pharmacology , Dose-Response Relationship, Immunologic , Enterotoxins/pharmacology , Humans , In Vitro Techniques , Lipid A/pharmacology , Neutrophils/metabolism , Salmonella typhimurium/pathogenicity
12.
Aust Dent J ; 35(2): 141-6, 1990 Apr.
Article in English | MEDLINE | ID: mdl-2189381

ABSTRACT

Proto-oncogenes are important in both normal cellular differentiation and in carcinogenesis. The majority of transforming genes belong to the ras family and the ras gene product has been shown to be elevated in some oral carcinomas. RAP-5 monoclonal antibody was used to determine the expression of the p21ras protein in normal and neoplastic oral mucosa in an immunohistological study. The expression of p21ras protein was generally restricted to acanthous cells with strong staining in normal oral mucosa and well-differentiated carcinomas. In contrast, the p21ras protein was not detected in significant amounts in severely dysplastic lesions and poorly differentiated carcinomas. These results suggest that expression of p21ras is a normal feature of more fully differentiated tissues, both normal and neoplastic, and is not useful as an indicator of cell proliferation or 'malignant potential'.


Subject(s)
Carcinoma, Papillary/analysis , Carcinoma, Squamous Cell/analysis , Mouth Mucosa/analysis , Mouth Neoplasms/analysis , Oncogene Protein p21(ras)/analysis , Antibodies, Monoclonal , Antigens, Differentiation/analysis , Cell Differentiation , Genes, ras , Humans , Mouth Mucosa/abnormalities
13.
Bol Oficina Sanit Panam ; 86(2): 131-40, 1979 Feb.
Article in Spanish | MEDLINE | ID: mdl-154906

ABSTRACT

PIP: Programming activities for the control of venereal diseases implies certain difficulties in Latin American countries owing to the lack of basic information and resources. It is perhaps for this reason that such programs have so far failed to achieve an adequate epidemiological impact. In late 1975, a new program was set up in Costa Rica with the following objectives: 1) reducing the incidence of venereal diseases; 2) detecting cases at an early stage in order to begin treatment; 3) developing a far-reaching hygiene education program; 4) establishing appropriate epidemiological surveillance machinery, including border-area programs; 5) integrating control activities with the general health services; 6) training personnel; and 7) carrying out research. Among the activities planned for the attainment of the aforementioned objectives was the detection of cases by means of voluntary presentation; surveillance of contacts; serological testing of pregnant women, blood donors, and applicants for health care identity cards, and other types of examination. Outpatient treatment was planned for all cases detected. Where epidemiological surveillance was concerned, it was proposed that improvements be made in morbidity report procedures, data analysis, and border-area programs. Plans were also made for integrating control activities into the basic health services and for reviewing the existing legislation with a view to expediting the implementation of the program. Steps taken to that end included the establishment of a more effective coordination of such activities with the Costa Rican Social Security Institute, an entity which attends the health needs of 80% of the population; a follow-up program for cases detected in the hospitals included in the program, and preparation of a flow diagram to be used for that purpose by such institutions. Other aspects considered were the distribution of treatment manuals, and information on epidemiological interview methods and laboratory techniques for the diagnosis and control of venereal diseases. In addition, posters and audiovisual modules were designed for use in public health education campaigns. (author's modified)^ieng


Subject(s)
Sexually Transmitted Diseases/prevention & control , Advertising , Costa Rica , Female , Humans , Male
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