CBCT in contemporary endodontics.

Cone-beam computed tomography (CBCT) is a three-dimensional imaging modality which can aid endodontic diagnosis and treatment planning. While there are guidelines available describing the indications, there are divergent philosophies on when this technology should be applied in clinical practice. This paper reviews the applications of CBCT including the clinical relevance of parameters which can be assessed, highlights the limitations of this technology, and provides guidance on how to maximise its clinical utility.

Overexpression of vascular permeability factor/vascular endothelial growth factor and its receptors in psoriasis.

Psoriatic skin is characterized by microvascular hyperpermeability and angioproliferation, but the mechanisms responsible are unknown. We report here that the hyperplastic epidermis of psoriatic skin expresses strikingly increased amounts of vascular permeability factor (VPF; vascular endothelial growth factor), a selective endothelial cell mitogen that enhances microvascular permeability. Moreover, two VPF receptors, kdr and flt-1, are overexpressed by papillary dermal microvascular endothelial cells. Transforming growth factor alpha (TGF-alpha), a cytokine that is also overexpressed in psoriatic epidermis, induced VPF gene expression by cultured epidermal keratinocytes. VPF secreted by TGF-alpha-stimulated keratinocytes was bioactive, as demonstrated by its mitogenic effect on dermal microvascular endothelial cells in vitro. Together, these findings suggest that TGF-alpha regulates VPF expression in psoriasis by an autocrine mechanism, leading to vascular hyperpermeability and angiogenesis. Similar mechanisms may operate in tumors and in healing skin wounds which also commonly express both VPF and TGF-alpha.

Expression of vascular permeability factor (vascular endothelial growth factor) by epidermal keratinocytes during wound healing.

Persistent microvascular hyperpermeability to plasma proteins even after the cessation of injury is a characteristic but poorly understood feature of normal wound healing. It results in extravasation of fibrinogen that clots to form fibrin, which serves as a provisional matrix and promotes angiogenesis and scar formation. We present evidence indicating that vascular permeability factor (VPF; also known as vascular endothelial growth factor) may be responsible for the hyperpermeable state, as well as the angiogenesis, that are characteristic of healing wounds. Hyperpermeable blood vessels were identified in healing split-thickness guinea pig and rat punch biopsy skin wounds by their capacity to extravasate circulating macromolecular tracers (colloidal carbon, fluoresceinated dextran). Vascular permeability was maximal at 2-3 d, but persisted as late as 7 d after wounding. Leaky vessels were found initially at the wound edges and later in the subepidermal granulation tissue as keratinocytes migrated to cover the denuded wound surface. Angiogenesis was also prominent within this 7-d interval. In situ hybridization revealed that greatly increased amounts of VPF mRNA were expressed by keratinocytes, initially those at the wound edge, and, at later intervals, keratinocytes that migrated to cover the wound surface; occasional mononuclear cells also expressed VPF mRNA. Secreted VPF was detected by immunofluoroassay of medium from cultured human keratinocytes. These data identify keratinocytes as an important source of VPF gene transcript and protein, correlate VPF expression with persistent vascular hyperpermeability and angiogenesis, and suggest that VPF is an important cytokine in wound healing.

Mast cells can secrete vascular permeability factor/ vascular endothelial cell growth factor and exhibit enhanced release after immunoglobulin E-dependent upregulation of fc epsilon receptor I expression.

Vascular permeability factor/vascular endothelial cell growth factor (VPF/VEGF) can both potently enhance vascular permeability and induce proliferation of vascular endothelial cells. We report here that mouse or human mast cells can produce and secrete VPF/VEGF. Mouse mast cells release VPF/VEGF upon stimulation through Fcepsilon receptor I (FcepsilonRI) or c-kit, or after challenge with the protein kinase C activator, phorbol myristate acetate, or the calcium ionophore, A23187; such mast cells can rapidly release VPF/VEGF, apparently from a preformed pool, and can then sustain release by secreting newly synthesized protein. Notably, the Fc epsilonRI-dependent secretion of VPF/VEGF by either mouse or human mast cells can be significantly increased in cells which have undergone upregulation of Fc epsilonRI surface expression by a 4-d preincubation with immunoglobulin E. These findings establish that at least one cell type, the mast cell, can be stimulated to secrete VPF/VEGF upon immunologically specific activation via a member of the multichain immune recognition receptor family. Our observations also identify a new mechanism by which mast cells can contribute to enhanced vascular permeability and/or angiogenesis, in both allergic diseases and other settings.

Vascular permeability factor/endothelial growth factor (VPF/VEGF): accumulation and expression in human synovial fluids and rheumatoid synovial tissue.

Vascular permeability factor (VPF, also known as vascular endothelial growth factor or VEGF), is a potent microvascular permeability enhancing cytokine and a selective mitogen for endothelial cells. It has been implicated in tumor angiogenesis and ascites fluid accumulation. Since development of the destructive synovial pannus in rheumatoid arthritis (RA) is associated with changes in vascular permeability (synovial fluid accumulation), synovial cell hyperplasia, and angiogenesis, we examined synovial fluids (SFs) and joint tissue for the expression and local accumulation of VPF/VEGF. VPF/VEGF was detected in all of 21 synovial fluids examined and when measured by an immunofluorimetric assay, ranged from 6.9 to 180.5 pM. These levels are biologically significant, since < 1 pM VPF/VEGF can elicit responses from its target cells, endothelial cells. Levels of VPF/VEGF were highest in rheumatoid arthritis fluids (n = 10), with a mean value (+/- SEM) of 59.1 +/- 18.0 pM, vs. 21.4 +/- 2.3 pM for 11 SFs from patients with other forms of arthritis (p = 0.042). In situ hybridization studies that were performed on joint tissues from patients with active RA revealed that synovial lining macrophages strongly expressed VPF/VEGF mRNA, and that microvascular endothelial cells of nearby blood vessels strongly expressed mRNA for the VPF/VEGF receptors, flt-1 and KDR. Immunohistochemistry performed on inflamed rheumatoid synovial tissue revealed that the VPF/VEGF peptide was localized to macrophages within inflamed synovium, as well as to microvascular endothelium, its putative target in the tissue. Together, these findings indicate that VPF/VEGF may have an important role in the pathogenesis of RA.

Distribution of vascular permeability factor (vascular endothelial growth factor) in tumors: concentration in tumor blood vessels.

Vascular permeability factor (VPF) is a highly conserved 34-42-kD protein secreted by many tumor cells. Among the most potent vascular permeability-enhancing factors known, VPF is also a selective vascular endothelial cell mitogen, and therefore has been called vascular endothelial cell growth factor (VEGF). Our goal was to define the cellular sites of VPF (VEGF) synthesis and accumulation in tumors in vivo. Immunohistochemical studies were performed on solid and ascites guinea pig line 1 and line 10 bile duct carcinomas using antibodies directed against peptides synthesized to represent the NH2-terminal and internal sequences of VPF. These antibodies stained tumor cells and, uniformly and most intensely, the endothelium of immediately adjacent blood vessels, both preexisting and those newly induced by tumor angiogenesis. A similar pattern of VPF staining was observed in autochthonous human lymphoma. In situ hybridization demonstrated VPF mRNA in nearly all line 10 tumor cells but not in tumor blood vessels, indicating that immunohistochemical labeling of tumor vessels with antibodies to VPF peptides reflects uptake of VPF, not endogenous synthesis. VPF protein staining was evident in adjacent preexisting venules and small veins as early as 5 h after tumor transplant and plateaued at maximally intense levels in newly induced tumor vessels by approximately 5 d. VPF-stained vessels were also hyperpermeable to macromolecules as judged by their capacity to accumulate circulating colloidal carbon. In contrast, vessels more than approximately 0.5 mm distant from tumors were not hyperpermeable and did not exhibit immunohistochemical staining for VPF. Vessel staining disappeared within 24-48 h of tumor rejection. These studies indicate that VPF is synthesized by tumor cells in vivo and accumulates in nearby blood vessels, its target of action. Because leaky tumor vessels initiate a cascade of events, which include plasma extravasation and which lead ultimately to angiogenesis and tumor stroma formation, VPF may have a pivotal role in promoting tumor growth. Also, VPF immunostaining provides a new marker for tumor blood vessels that may be exploitable for tumor imaging or therapy.

Control of hair growth and follicle size by VEGF-mediated angiogenesis.

The murine hair follicle undergoes pronounced cyclic expansion and regression, leading to rapidly changing demands for its vascular support. Our study aimed to quantify the cyclic changes of perifollicular vascularization and to characterize the biological role of VEGF for hair growth, angiogenesis, and follicle cycling. We found a significant increase in perifollicular vascularization during the growth phase (anagen) of the hair cycle, followed by regression of angiogenic blood vessels during the involution (catagen) and the resting (telogen) phase. Perifollicular angiogenesis was temporally and spatially correlated with upregulation of VEGF mRNA expression by follicular keratinocytes of the outer root sheath, but not by dermal papilla cells. Transgenic overexpression of VEGF in outer root sheath keratinocytes of hair follicles strongly induced perifollicular vascularization, resulting in accelerated hair regrowth after depilation and in increased size of hair follicles and hair shafts. Conversely, systemic treatment with a neutralizing anti-VEGF antibody led to hair growth retardation and reduced hair follicle size. No effects of VEGF treatment or VEGF blockade were observed in mouse vibrissa organ cultures, which lack a functional vascular system. These results identify VEGF as a major mediator of hair follicle growth and cycling and provide the first direct evidence that improved follicle vascularization promotes hair growth and increases hair follicle and hair size.

Vascular permeability factor (vascular endothelial growth factor) gene is expressed differentially in normal tissues, macrophages, and tumors.

Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), increases microvascular permeability and is a specific mitogen for endothelial cells. Expression of VPF/VEGF previously was demonstrated in a variety of tumor cells, in cultures of pituitary-derived cells, and in corpus luteum. Here we present evidence, by Northern analysis and in situ hybridization, that the VPF/VEGF gene is expressed in many adult organs, including lung, kidney, adrenal gland, heart, liver, and stomach mucosa, as well as in elicited peritoneal macrophages. The highest levels of VPF/VEGF transcripts were found in epithelial cells of lung alveoli, renal glomeruli and adrenal cortex, and in cardiac myocytes. The prominence of VPF/VEGF mRNA in these tissues suggests a possible role for VPF/VEGF in regulating baseline microvascular permeability, which is essential for tissue nutrition and waste removal. We also demonstrate particularly high VPF/VEGF mRNA levels in several human tumors, where it may be involved in promoting tumor angiogenesis and stroma generation, both as an endothelial cell mitogen and indirectly by its permeability enhancing effect that leads to the deposition of a provisional fibrin gel matrix.

Expression and distribution of osteopontin in human tissues: widespread association with luminal epithelial surfaces.

Osteopontin, a glycoprotein with a glycine-arginine-glycine-aspartate-serine (GRGDS) cell-binding domain, has been described in bone and is also known to be expressed in other organs, particularly kidney. The goal of the present work was to define the distribution of osteopontin synthesis and deposition in a wide variety of normal adult human tissues using a multifaceted approach that included immunohistochemistry, in situ hybridization, and Northern analysis. Immunohistochemical studies have revealed the unexpected finding that osteopontin is deposited as a prominent layer at the luminal surfaces of specific populations of epithelial cells of the gastrointestinal tract, gall bladder, pancreas, urinary and reproductive tracts, lung, breast, salivary glands, and sweat glands. Northern analyses identified gallbladder as a major site of osteopontin gene transcription comparable in magnitude with that of kidney, and immunoblotting identified osteopontin in bile. In situ hybridization localized osteopontin gene transcripts predominantly to the epithelium of a variety of organs as well as to ganglion cells of bowel wall. Osteopontin of epithelial cell origin, like bone-derived osteopontin, promoted GRGDS-dependent cell spreading in attachment assays. We postulate that osteopontin secreted by epithelium binds integrins on luminal surfaces. Collectively, these findings suggest an important role for osteopontin on many luminal epithelial surfaces communicating with the external environment.

Fibrin deposition in autochthonous Syrian hamster pancreatic adenocarcinomas induced by the chemical carcinogen N-nitroso-bis(2-oxopropyl)amine.

Immunofluorescence studies have demonstrated the presence of fib (a group of fibrinogen- and fibrin-related proteins that react with antibodies raised against fibrinogen) in the stroma of several transplantable animal and autochthonous human tumors. Acceptance of these reports was tempered by the possibility of artifactual clotting and fibrinolysis associated with tumor removal or tumor transplantation and by the relatively poor histology inevitable when immunofluorescence is performed on frozen tissue sections. An immunoperoxidase study therefore was undertaken of the ductal pancreatic carcinomas induced in female LGV Syrian hamsters by N-nitroso-bis(2-oxopropyl)amine [(BOP) CAS: 60599-38-4]. Artifactual clotting and fibrinolysis associated with tumor removal were avoided by systemic anticoagulation and antifibrinolysis. Fibronectin and residual fib were prominent components of tumor stroma. Prominent fib deposits also were found in a new location: the basement membrane zones of atypical pancreatic ducts and invasive carcinomas. In contrast, fib deposits were never found in the basement membranes of blood vessels, nerves, or pancreatic acini of BOP-treated or normal animals, or in the ductal basement membranes in the normal pancreas. Ducts with marked atypicality and invasive pancreatic carcinomas frequently exhibited discontinuous basement membrane staining for fib, which often paralleled loss of staining for the integral basement membrane proteins--type IV collagen and laminin. Loss of acquired fib basement membrane staining with malignant disease progression may serve as a new marker for local tumor invasion.

Vascular permeability factor (vascular endothelial growth factor) expression and angiogenesis in cervical neoplasia.

BACKGROUND: Angiogenesis is a critical factor in the progression of solid tumors, including cervical cancers. The mechanisms responsible for angiogenesis in cervical neoplasia, however, are not well defined. PURPOSE: Our goal was to determine the relationship between angiogenesis and the expression of the angiogenic cytokine vascular permeability factor (VPF), also known as vascular endothelial growth factor, and its receptors in cervical neoplasia. METHODS: Sixty-six cervical biopsy specimens were evaluated; among these, 16 samples were designated as benign, 17 as low-grade squamous intraepithelial lesions, 18 as high-grade squamous intraepithelial lesions, and 15 as invasive squamous cell carcinomas. Histologic sections immunostained for factor VIII-related antigen were evaluated quantitatively for microvessel density and for the presence of epithelial-stromal vascular cuffing. Sections were also evaluated for VPF messenger RNA (mRNA) expression by in situ hybridization. RESULTS: VPF mRNA expression, epithelial-stromal vascular cuffing, and microvessel density counts were significantly increased in invasive carcinoma and in high-grade intraepithelial lesions as compared with low-grade intraepithelial lesions and benign squamous epithelium. Vascular cuffing and increased microvessel density counts were also significantly associated with increased VPF mRNA expression. CONCLUSIONS: These observations suggest that VPF is an important angiogenic factor in cervical neoplasia.

Fibrinogen influx and accumulation of cross-linked fibrin in mouse carcinomas.

125I-radiolabeled guinea pig fibrinogen was used to measure the influx (20 min) and accumulation (18 h) of fibrinogen/fibrin in three transplantable carcinomas (Lewis lung, TA3/St mammary, and MOT ovarian) growing in the subcutaneous space of syngeneic mice. Fibrinogen influx and, to an even greater extent, fibrin accumulation were substantially increased in all three tumors, as compared with normal control tissues. A significantly larger fraction of tumor-associated than control tissue radioactivity was insoluble in 3 M urea, a property of cross-linked fibrin. Positive identification of cross-linked fibrin was made by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography of tumor extracts. Tumor fibrin deposits were localized by immunoperoxidase staining of tissue sections. Fibrin accumulation was also significantly increased in premalignant hyperplastic alveolar nodules that had been transplanted to cleared mammary fat pads, as compared with normal mammary tissue, and was further increased in primary mammary carcinomas that arose from hyperplastic alveolar nodules. These findings generalize to the mouse the principles that tumor vessels are hyperpermeable to plasma proteins and that fibrin accumulates in transplantable and primary tumors. Further, they demonstrate that tumor fibrin is cross-linked and therefore analogous to the fibrin deposited in thrombi, wounds, and cellular immunity.

Expression of vascular permeability factor/vascular endothelial growth factor by melanoma cells increases tumor growth, angiogenesis, and experimental metastasis.

Vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF) is an angiogenic cytokine expressed by many human and animal tumors. Hypoxia often up-regulates VPF/VEGF expression further. To better define the role of VPF/VEGF in tumor biology, we screened tumorigenic lines for those expressing minimal constitutive and hypoxia-inducible VPF/VEGF. Human melanoma SK-MEL-2 cells best fit these criteria and formed small, poorly vascularized tumors in immunodeficient mice. We transfected SK-MEL-2 cells stably with sense or antisense mouse VPF/VEGF cDNA or with vector alone. Cells transfected with sense VPF/VEGF (V+) expressed and secreted large amounts of mouse VPF/VEGF and formed well-vascularized tumors with hyperpermeable blood vessels and minimal necrosis in nude/SCID mice. Antisense-transfected VPF/VEGF (V-) cells expressed reduced constitutive VPF/VEGF and no detectable mouse VPF/VEGF, and formed small, minimally vascularized tumors exhibiting extensive necrosis. Vector-alone transfectants (N1 cells) behaved like parental cells. V+ cells formed numerous lung tumor colonies in SCID mice, approximately 50-fold more than N1 cells, whereas V- cells formed few or none. These experiments demonstrate that VPF/VEGF promotes melanoma growth by stimulating angiogenesis and that constitutive VPF/VEGF expression dramatically promotes tumor colonization in the lung.

Expression of vascular permeability factor (vascular endothelial growth factor) and its receptors in adenocarcinomas of the gastrointestinal tract.

Vascular permeability factor (VPF) is one of the most potent known inducers of microvascular hyperpermeability; in addition, it is a selective endothelial cell growth factor, hence its alternate name, vascular endothelial growth factor. VPF exerts its actions on the microvasculature by interacting with specific endothelial cell receptors. VPF is expressed by many transplantable animal tumors, by tumor cell lines in culture, and by certain normal cells in situ. The purpose of the present investigation was to determine whether and with what consistency VPF and its endothelial cell receptors are expressed in primary autochthonous human tumor of gastrointestinal tract origin, as determined by in situ hybridization and immunohistochemistry. Twenty-one primary adenocarcinomas (17 colon, 2 stomach, 1 small bowel, and 1 pancreas) were studied. The malignant epithelial cells expressed VPF mRNA strongly, in contrast to normal epithelium, hyperplastic polyps, and adenomas, which expressed little or no VPF mRNA. VPF expression was further increased in tumor cells immediately adjacent to zones of tumor necrosis; in such areas, occasional stromal cells also expressed VPF mRNA. In the ten colon carcinomas studied, tumor cells stained for VPF protein by immunohistochemistry. The endothelial cells of nearby stromal blood vessels also stained for VPF by immunohistochemistry and in addition expressed mRNAs encoding the VPF receptors flt-1 and kdr as determined by in situ hybridization. Endothelial cells away from the tumor did not stain for VPF and no definite mRNA expression for flt-1 or kdr was detected by in situ hybridization. The ganglion cells of the myenteric plexus of normal bowel expressed VPF mRNA and protein. These data indicate that primary autochthonous human tumors of gastrointestinal origin regularly express both VPF mRNA and VPF protein and that adjacent stromal vessels express mRNAs for both known VPF receptors. VPF is likely to contribute to tumor growth by promoting angiogenesis and stroma formation, both directly, through its action as an endothelial cell growth factor, and indirectly, by increasing vascular permeability, thereby leading to plasma protein extravasation, fibrin deposition, and the eventual replacement of the resulting matrix with vascularized stroma.

Pathogenesis of tumor stroma generation: a critical role for leaky blood vessels and fibrin deposition.

Tumor stroma formation results from the interaction of tumor cells and their products with the host and certain of its normal defense mechanisms, particularly the clotting and fibrinolytic systems. It is a process in which tumor cells render local venules and veins hyperpermeable with the result that fibrinogen and other proteins extravasate and clot, forming an extravascular crosslinked fibrin gel. Coagulation is mediated by an interaction between extravasated plasma clotting factors and tumor-associated and perhaps other tissue procoagulants. Parallel activation of the fibrinolytic system leads to substantial fibrin turnover, but fibrin nonetheless accumulates in amounts, variable from tumor to tumor, that are sufficient to provide a provisional stroma. This provisional stroma imposes on tumor cells a structure that persists even as tumor cells multiply and as the fibrin provisional stroma is replaced by mature connective tissue. The provisional fibrin stroma also serves to regulate the influx of macrophages, and perhaps other inflammatory cells, but at the same time, and in ways that are not fully understood, facilitates the inward migration of new blood vessels and fibroblasts, integral components of mature tumor stroma. Ascites tumors differ from solid tumors in that fibrin gel is not ordinarily deposited in body cavities and, as a result, there is no provisional stroma to impose an initial structure. Tumor stroma generation resembles the process of wound healing in many respects. However, it differs in the mechanism of its initiation, and in the apparent lack of a role for platelets. It also differs fundamentally in that invading tumor cells continually render new vessels hyperpermeable to plasma, thus perpetuating the cycle of extravascular fibrin deposition. In this sense, tumors behave as wounds that do not heal. Largely neglected in this review has been discussion of the numerous cytokines, mitogens, and growth factors that are widely believed to play important roles in tumor angiogenesis and wound healing; i.e., PDGF, FGF, EGF, TGF alpha, TGF beta, TNF, interferons, etc. This omission has been intentional, and for two reasons. First, these cytokines have already received considerable attention [100,123-128]. Second, it is not yet clear how closely the actions of these molecules, as described in vitro, relate to their functions in vivo. At present we are deluged with a surfeit of factors that have the capacity to induce new blood vessel formation in angiogenesis assays; these factors include not only peptides but lipids and even ions [126,129-131].(ABSTRACT TRUNCATED AT 400 WORDS)

Vascular permeability factor/vascular endothelial growth factor and the significance of microvascular hyperpermeability in angiogenesis.

This Chapter has reviewed the literature concerning VPF/VEGF as a potent vascular permeabilizing cytokine. In accord with this important role, microvessels have been found to be hyperpermeable to plasma proteins and other circulating macromolecules at sites where VPF/VEGF and its receptors are overexpressed, i.e., in tumors, healing wounds, retinopathies, many important inflammatory conditions and in certain physiological processes, such as ovulation and corpus luteum formation. Moreover, microvascular hyperpermeability to plasma proteins was shown to have an important consequence: the laying down of a fibrin-rich extracellular matrix. This provisional matrix, in turn, favors and supports the ingrowth of fibroblasts and endothelial cells which, together, transform the provisional matrix into the mature stroma characteristic of tumors and healed wounds. Finally, we have considered the pathways by which these and other circulating macromolecules cross the endothelium of normal and VPF/VEGF-permeabilized microvessels. These pathways include VVOs and trans-endothelial openings that have been variously interpreted as inter-endothelial cell gaps or trans-endothelial cell pores. At least some trans-endothelial cell pores may arise from VVOs. In conclusion, these data provide new insights into the mechanisms of angiogenesis and stroma formation, insights which are potentially applicable to a wide variety of disease states and which may lead to identification of new targets for therapeutic intervention.

Identification of a novel gene, selectively up-regulated in human carcinomas, using the differential display technique.

Using the differential display technique, selecting for genes up-regulated in renal cell carcinoma compared with normal renal parenchyma, we isolated a novel gene, designated DD96. As determined by in situ and Northern blot hybridization studies, DD96 is expressed only in rare normal epithelial cell populations, such as the proximal tubular epithelial cells of the kidney. However, it is expressed diffusely in malignant epithelial cells of the wide majority of renal cell carcinomas. In addition, DD96 is overexpressed markedly in various human carcinomas originating from the colon, breast, and lung, as well as in a number of cell lines derived from tumors of these organs compared with normal epithelial cell populations. Furthermore, the expression of DD96 is induced in immortalized breast ductal epithelial cell lines compared with normal breast ductal epithelial cells, and, in vivo, in premalignant conditions, such as adenoma of the colon and ductal carcinoma in situ of the breast. Sequence analysis of a complete cDNA clone isolated from a human kidney cDNA library revealed that DD96 encodes for a protein of approximately Mr 13,500. These results suggest that DD96 may play a role in the early events associated with malignant transformation; however, its function remains to be determined.

Vascular stroma formation in carcinoma in situ, invasive carcinoma, and metastatic carcinoma of the breast.

The generation of vascular stroma is essential for solid tumor growth and involves stimulatory and inhibiting factors as well as stromal components that regulate functions such as cellular adhesion, migration, and gene expression. In an effort to obtain a more integrated understanding of vascular stroma formation in breast carcinoma, we examined expression of the angiogenic factor vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF); the VPF/VEGF receptors flt-1 and KDR; thrombospondin-1, which has been reported to inhibit angiogenesis; and the stromal components collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin by mRNA in situ hybridization on frozen sections of 113 blocks of breast tissue from 68 patients including 28 sections of breast tissue without malignancy, 18 with in situ carcinomas, 56 with invasive carcinomas, and 8 with metastatic carcinomas. A characteristic expression profile emerged that was remarkably similar in invasive carcinoma, carcinoma in situ, and metastatic carcinoma, with the following characteristics: strong tumor cell expression of VPF/VEGF; strong endothelial cell expression of VPF/VEGF receptors; strong expression of thrombospondin-1 by stromal cells and occasionally by tumor cells; and strong stromal cell expression of collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin. The formation of vascular stroma preceded invasion, raising the possibility that tumor cells invade not into normal breast stroma but rather into a richly vascular stroma that they have induced. Similarly, tumor cells at sites of metastasis appear to induce the vascular stroma in which they grow. We conclude that a distinct pattern of mRNA expression characterizes the generation of vascular stroma in breast cancer and that the formation of vascular stroma may play a role not only in growth of the primary tumor but also in invasion and metastasis.

Inadequate record keeping by dental practitioners.

BACKGROUND: When a dental practitioner is brought before a disciplinary body, a common finding is that dental records were poorly kept and inadequate to establish issues of consent for treatment or the nature of the treatment undertaken. Often this finding may be incidental to the actual issue that brought the practitioner before a regulatory body or the Courts. The aim of this study was to examine recent cases reported in the State of Victoria involving dental practitioners, specifically seeking those cases where the record keeping was found to be inadequate as an incidental finding. METHODS: Published rulings of formal complaints and notification cases brought before disciplinary hearings in the State of Victoria for the period January 2000 to June 2014 were analysed with regards to orders made in respect to record keeping. RESULTS: Complaints and notifications specific to dental record keeping accounted for less than 2% of formal complaints. And yet up to 75% of cases have made a finding of unprofessional conduct against a dental practitioner on the basis of inadequate record keeping, most often in combination with other breaches of conduct. CONCLUSIONS: Adherence to the traditional format of handwriting or typing entries into patient records may contribute to the problem of poor record keeping in a clinical dental setting. Newer technologies such as digital intraoral and extraoral photography and audio-recording of patient interactions may offer a solution to the problems of record keeping.

The growth of Medicare rebatable cone beam computed tomography and panoramic radiography in Australia.

BACKGROUND: There is a lack of objective data documenting the growth of cone beam radiology in Australia. Medicare rebates for cone beam computed tomography (CBCT) scans have been available since 1 July 2011. The aim of this study was to examine the Medicare data on the use of CBCT in order to quantify the growth of this technology over a three-year period and to assess if the growth of CBCT was impacting upon the use of dental panoramic radiology. METHODS: The Medicare dataset was accessed, and data relating to the number and distribution of CBCTs and panoramic radiographs (PRs) were extracted. The data were broken down by state and territory, as well as by age group and gender of the patient, for the financial year periods July 2011 to June 2012, July 2012 to June 2013 and July 2013 to June 2014. Items relating to PRs were also extracted for the periods 2005-2008 and 2008-2011. RESULTS: In the period July 2011 to June 2014, a total of 226 232 CBCTs and 2 881 351 PRs were rebated through Medicare. The rate of CBCT services provided per 100 000 population increased by 42.3% over the three-year period, whereas the rate of PRs remained fairly constant. From the age group 5-14 years through to 55-64 years, females received more CBCTs and PRs than males. The total number of PRs rebated through Medicare increased slightly over each previous three-year period (2005-2008 and 2008-2011). CONCLUSIONS: There has been rapid growth of the use of CBCT over a three-year period, most marked in the State of Victoria. The higher number of CBCT examinations in females across almost all age groups, but most notably in the 15-24 years age group, raises questions about clinical decision making in the selection of cone beam imaging. There was little evidence that CBCTs were being used as a substitute for PRs, except for a small but consistent drop in the number of PRs being requested for diagnosis of surgically related dental conditions.