Homology between alpha 2(V) and alpha 1(III) collagen promoters and evidence for negatively acting elements in the alpha 2(V) first intron and 5' flanking sequences

We have isolated a 17 kilobase pair (kb) genomic clone containing the 5' portion of the human alpha 2(V) collagen gene. Nucleotide sequence was determined for 1671 base pairs (bp) comprising the promoter region, first exon and 334 bp of the first intron, and the major transcriptional start site determined by primer extension and S1 nuclease analysis. Sequence comparison revealed the alpha 2(V) promoter to be similar in structure to the promoter of the alpha 1(III) collagen gene. This is the first instance of such similarities between promoter regions of genes encoding different fibrillar collagen chains. Homology, in 5' flanking sequences, extends upstream to about nucleotide -120 in each gene and is particularly striking near the TATTTA sequence (TATA box) present in each promoter. Some homology also surrounds the two transcription start sites. The 5' untranslated regions of the two genes also show strong homology. Chimeric chloramphenicol acetyltransferase (CAT) constructs were prepared with various fragments from the 5' portion of the alpha 2(V) gene. Transient expression assays, in human fibroblasts, localized the functional alpha 2(V) promoter to the region of 5' flanking sequence conserved between the alpha 2(V) and alpha 1(III) genes. Expression assays also identified negatively acting elements, in intron and 5' flanking sequences, which inhibit transcription from the alpha 2(V) promoter.

Hairy leukoplakia; lessons learned: 30-plus years

Well into the fourth decade of the HIV/AIDS pandemic, we can look back on the early years, the initial discoveries, and the broad sweep of the progress of our understanding of the nature, causes, and significance of the oral lesions seen in those infected with the virus. Prominent among these is oral hairy leukoplakia (HL), a previously unknown lesion of the mouth associated with Epstein-Barr virus (EBV) and initially seen only in people with AIDS, in the then-recognized risk groups, or those shown to be HIV positive. Subsequently, it became clear that the distribution of HL extends well beyond the HIV spectrum. In this brief review, we consider the clinical and histological features of HL, discuss how it was discovered, explore its cause, diagnosis, relationship with AIDS, pathogenesis, significance in EBV biology, options for management, and how it changes with HIV/AIDS therapy.

BMP1 and TLL1 Are Required for Maintaining Periodontal Homeostasis

Mutations in bone morphogenetic protein 1 (BMP1) in humans or deletion of BMP1 and related protease tolloid like 1 (TLL1) in mice lead to osteogenesis imperfecta (OI). Here, we show progressive periodontal defects in mice in which both BMP1 and TLL1 have been conditionally ablated, including malformed periodontal ligament (PDL) (recently shown to play key roles in normal alveolar bone formation), significant loss in alveolar bone mass ( P < 0.01), and a sharp reduction in cellular cementum. Molecular mechanism studies revealed a dramatic increase in the uncleaved precursor of type I collagen (procollagen I) and a reduction in dentin matrix protein 1 (DMP1), which is partially responsible for defects in extracellular matrix (ECM) formation and mineralization. We also showed a marked increase in the expression of matrix metallopeptidase 13 (MMP13) and tartrate-resistant acid phosphatase (TRAP), leading to an acceleration in periodontal breakdown. Finally, we demonstrated that systemic application of antibiotics significantly improved the alveolar bone and PDL damage of the knockdown phenotype, which are thus shown to be partially secondary to pathogen-induced inflammation. Together, identification of the novel roles of BMP1 and TLL1 in maintaining homeostasis of periodontal formation, partly via biosynthetic processing of procollagen I and DMP1, provides novel insights into key contributions of the extracellular matrix environment to periodontal homeostasis and contributes toward understanding of the pathology of periodontitis.

Incidence of Oral Lesions in HIV-1-infected Women: Reduction with HAART

Few studies assess the effectiveness of HAART on reducing the incidence and recurrence of oral lesions. We investigated such changes among 503 HIV+ women over six years in the Women’s Interagency HIV Study. The incidence of erythematous candidiasis (EC), pseudomembranous candidiasis (PC), hairy leukoplakia (HL), and warts was computed over follow-up visits after HAART initiation compared with before HAART initiation. Analysis of our data demonstrates a strong decrease in candidiasis after HAART initiation. The incidence of EC fell to 2.99% from 5.48% (RR 0.545); PC fell to 2.85% from 6.70% (RR 0.425); and EC or PC fell to 3.43% from 7.35% (RR 0.466). No changes were seen in HL or warts. Higher HIV-RNA was associated with greater incidence of candidiasis and HL, but not warts. Analysis of these data indicates that recurrence and incidence of candidiasis are reduced by HAART, and that recurrence is reduced independently of CD4 and HIV-RNA.

Oral Lesions of HIV Disease and HAART in Industrialized Countries

The epidemiology of HIV-related oral disease in industrialized nations has evolved following the initial manifestations described in 1982. Studies from both the Americas and Europe report a decreased frequency of HIV-related oral manifestations of 10–50% following the introduction of HAART (highly active antiretroviral therapy). Evidence suggests that HAART plays an important role in controlling the occurrence of oral candidosis. The effect of HAART on reducing the incidence of oral lesions, other than oral candidosis, does not appear as significant, possibly as a result of low lesion prevalence in industrialized countries. In contrast to other oral manifestations of HIV, an increased prevalence of oral warts in patients on HAART has been reported from the USA and the UK. HIV-related salivary gland disease may show a trend of rising prevalence in the USA and Europe. The re-emergence of HIV-related oral disease may be indicative of failing therapy. A range of orofacial iatrogenic consequences of HAART has been reported, and it is often difficult to distinguish between true HIV-related oral disease manifestations and the adverse effects of HAART. A possible association between an increased risk of oral squamous cell carcinoma and HIV infection has been suggested by at least three epidemiological studies, with reference to the lip and tongue. These substantial and intensive research efforts directed toward enhancing knowledge regarding the orofacial consequences of HIV infection in the industrialized nations require dissemination in the wider health care environment.

Differential requirement for P2X7R function in IL-17 dependent vs. IL-17 independent cellular immune responses

IL17-dependent autoimmunity to collagen type V (Col V) has been associated with lung transplant obliterative bronchiolitis. Unlike the T helper 1 (Th1)-dependent immune responses to Tetanus Toxoid (TT), the Th17 response to Col V in lung transplant patients and its Th1/17 variant observed in coronary artery disease patients requires IL-1β, tumor necrosis factor α and CD14(+) cells. Given the involvement of the P2X7 receptor (P2X7R) in monocyte IL-1β responses, we investigated its role in Th17-, Th1/17- and Th1-mediated proinflammatory responses. Transfer of antigen-pulsed peripheral blood mononucleated cells (PBMCs) from Col V-reactive patients into SCID mouse footpads along with P2X7R antagonists revealed a selective inhibition of Col V-, but not TT-specific swelling responses. P2X7R inhibitors blocked IL-1β induction from monocytes, including both Col V-α1 peptide-induced (T-dependent), as well as native Col V-induced (T-independent) responses. Significantly higher P2X7R expression was found on CXCR3(neg) CCR4(+)/6(+) CD4(+) [Th17] versus CXCR3(+)CCR4/6(neg) CD4(+) [Th1] subsets in PBMCs, suggesting that the paradigm of selective dependence on P2X7R might extend beyond Col V autoimmunity. Indeed, P2X7R inhibitors suppressed not only anti-Col V, but also Th1/17-mediated alloimmunity, in a heart transplant patient without affecting anti-viral Epstein-Barr virus responses. These results suggest that agents targeting the P2X7R might effectively treat Th17-related transplant pathologies, while maintaining Th1-immunity to infection.

The Oral HIV/AIDS Research Alliance: updated case definitions of oral disease endpoints

The Oral HIV/AIDS Research Alliance (OHARA) is part of the AIDS Clinical Trials Group (ACTG), the largest HIV clinical trials organization in the world. Its main objective is to investigate oral complications associated with HIV/AIDS as the epidemic is evolving, in particular, the effects of antiretrovirals on oral mucosal lesion development and associated fungal and viral pathogens. The OHARA infrastructure comprises: the Epidemiologic Research Unit (at the University of California San Francisco), the Medical Mycology Unit (at Case Western Reserve University) and the Virology/Specimen Banking Unit (at the University of North Carolina). The team includes dentists, physicians, virologists, mycologists, immunologists, epidemiologists and statisticians. Observational studies and clinical trials are being implemented at ACTG-affiliated sites in the US and resource-poor countries. Many studies have shared end-points, which include oral diseases known to be associated with HIV/AIDS measured by trained and calibrated ACTG study nurses. In preparation for future protocols, we have updated existing diagnostic criteria of the oral manifestations of HIV published in 1992 and 1993. The proposed case definitions are designed to be used in large-scale epidemiologic studies and clinical trials, in both US and resource-poor settings, where diagnoses may be made by non-dental healthcare providers. The objective of this article is to present updated case definitions for HIV-related oral diseases that will be used to measure standardized clinical end-points in OHARA studies, and that can be used by any investigator outside of OHARA/ACTG conducting clinical research that pertains to these end-points.

Effect of HAART on salivary gland function in the Women's Interagency HIV Study (WIHS)

OBJECTIVE

To determine the impact of highly active antiretroviral therapy (HAART) on salivary gland function in human immunodeficiency virus (HIV) positive women from the Women's Interagency HIV Study (WIHS).

DESIGN

Longitudinal cohort study.

SUBJECTS AND METHODS

A total of 668 HIV positive women from the WIHS cohort with an initial and at least one follow-up oral sub-study visit contributed 5358 visits. Salivary gland function was assessed based on a dry mouth questionnaire, whole unstimulated and stimulated salivary flow rates, salivary gland enlargement or tenderness and lack of saliva on palpation of the major salivary glands.

MAIN OUTCOME MEASURES

Changes in unstimulated and stimulated flow rates at any given visit from that of the immediate prior visit (continuous variables). The development of self-reported dry mouth (present/absent), enlargement or tenderness of salivary glands (present/absent), and absence of secretion on palpation of the salivary glands were binary outcomes (yes/no).

RESULTS

Protease Inhibitor (PI) based HAART was a significant risk factor for developing decreased unstimulated (P = 0.01) and stimulated (P = 0.0004) salivary flow rates as well as salivary gland enlargement (P = 0.006) as compared with non-PI based HAART.

CONCLUSIONS

PI-based HAART therapy is a significant risk factor for developing reduced salivary flow rates and salivary gland enlargement in HIV positive patients.

Oral health-related quality of life among HIV-infected and at-risk women

OBJECTIVES

Objective measures of dental diseases reflect only their clinical end-point. There is a need to use multidimensional measures of diseases that consider their psychosocial aspects and functional impact. The aim of this study is to compare the oral health-related quality of life (OHRQOL) between a group of HIV-infected women and a similar group of at-risk HIV-uninfected women, and to investigate the role of potential confounding clinical oral health and behavioral factors.

METHODS

Our sample included HIV-infected women (87%) and women at risk for HIV infection (13%) followed up for 5.5 years. OHRQOL was measured using the short version of the Oral Health Impact Profile (OHIP-14), which is a validated and reliable instrument.

RESULTS

HIV-infected women averaged 10% poorer OHRQOL than HIV-uninfected women; this difference was not apparent after adjusting for the number of study visits attended and significant behavioral and clinical oral health factors. The OHRQOL was inversely related to dental and periodontal diseases and to smoking and freebase cocaine use; these relationships were not confounded by HIV status.

CONCLUSIONS

The study identified specific clinical and behavioral factors where dental professionals can intervene to possibly improve the OHRQOL of HIV-infected or at-risk HIV-uninfected women.

Potential of biomimetic surfaces to promote in vitro osteoblast-like cell differentiation

Bioactive glasses, osteoproductive materials, have received considerable attention as bone graft substitutes in the treatment of bony defects. More recent strategies for achieving a predictable periodontal regeneration include the use of enamel matrix proteins, due to their role in the formation of bone tissue. The aim of our study is to examine the effects of these materials on the proliferation and differentiation of the mouse preosteoblastic cell line MC3T3-E1. Cells were cultured up to 28 days in contact with three types of granules: Bioglass 45S5 granules (BG), 45S5 granules coated with enamel matrix proteins (Emdogain) (BG/EMD), and a less reactive glass used as a control (60S). Phase contrast microscopic observations have shown that all substrates supported the growth of osteoblastic cells. Zones of differentiation were observed at an earlier stage in cultures of BG and BG/EMD. TEM observations revealed ultrastructural features very close to what is observed in vivo during intramembranous ossification with a direct bone apposition on the bioactive glasses. Total protein production was higher in the cultures with BG and BG/EMD. Northern Blot analysis revealed a stimulation of the transcription factor Cbfa1/Runx2 at day 13 in cultures of BG when compared to the two other cultures. Bone sialoprotein (early marker of differentiation) and osteocalcin (marker of late-stage differentiation) expression was increased in cultures with BG and BG/EMD when compared to 60S. Taken together, our findings indicate that Bioglass alone or combined with Emdogain, have the ability to support the growth of osteoblast-like cells in vitro and to promote osteoblast differentiation by stimulating the expression of major phenotypic markers. In addition, we noticed that the bioactive granules coated with Emdogain revealed significantly higher protein production than the bioactive granules alone at day 20.

Dental caries in HIV-seropositive women

Reports that compare dental caries indices in HIV-seropositive (HIV+) subjects with HIV-seronegative (HIV-) subjects are rare. The objective of this study was to determine if there was an association between HIV infection and dental caries among women enrolled in the Women's Interagency HIV Study. Subjects included 538 HIV+ and 141 HIV- women at baseline and 242 HIV+ and 66 HIV- women at year 5. Caries indices included DMFS and DFS (coronal caries) and DFSrc (root caries). Cross-sectional analysis of coronal caries data revealed a 1.2-fold-higher caries prevalence among HIV+ women compared with HIV- women. Longitudinally, DMFS increased with increasing age and lower average stimulated salivary volume. Root caries results were not significant except for an overall increased DFSrc associated with smoking. Anti-retroviral therapy was not identified as a risk factor for dental caries.

Novel starch thermoplastic/Bioglass composites: mechanical properties, degradation behavior and in-vitro bioactivity

The present research aims to evaluate the possibility of creating new degradable, stiff and highly bioactive composites based on a biodegradable thermoplastic starch-based polymeric blend and a Bioglass filler. Such combination should allow for the development of bioactive and degradable composites with a great potential for a range of temporary applications. A blend of starch with ethylene-vinyl alcohol copolymer (SEVA-C) was reinforced with a 45S5 Bioglass powder presenting a granulometric distribution between 38 and 53 microm. Composites with 10 and 40 wt % of 45S5 Bioglass were compounded by twin-screw extrusion (TSE) and subsequently injection molded under optimized conditions. The mechanical properties of the composites were evaluated by tensile testing, and their bioactivity assessed by immersion in a simulated body fluid (SBF) for different periods of time. The biodegradability of these composites was also monitored after several immersion periods in an isotonic saline solution. The tensile tests results obtained indicated that SEVA-C/Bioglass composites present a slightly higher stiffness and strength (a modulus of 3.8 GPa and UTS of 38.6 MPa) than previously developed SEVA-C/Hydroxylapatite (HA) composites. The bioactivity of SEVA-C composites becomes relevant for 45S5 amounts of only 10 wt %. This was observed by scanning electron microscopy (SEM) and confirmed for immersion periods up to 30 days by both thin-film X-ray diffraction (TF-XRD) (where HA typical peaks are clearly observed) and induced coupled plasma emission (ICP) spectroscopy used to follow the elemental composition of the SBF as function of time. Additionally, it was observed that the composites are biodegradable being the results correlated with the correspondent materials composition.

In situ study of partially crystallized Bioglass and hydroxylapatite in vitro bioactivity using atomic force microscopy

The present work investigates, in situ, the in vitro bioactivity of partially crystallized 45S5 Bioglass (BG) as a function of immersion time in a simulated body fluid (SBF) using atomic force microscopy (AFM). The results obtained for the crystallized BG were compared to those of hydroxyapatite c- and a-faces. The calcium phosphate layer grows on the crystallized 45S5 B by multiple two-dimensional nucleation and fusion of these two-dimensional islands, which is essentially the same mode as for the hydroxyapatite c-face. The surface of the crystallized 45S5 BG was almost fully covered with a dense and compact calcium phosphate layer after 24 h. The calcium phosphate formation on the crystallized BG arises from a low surface energy of the surface layer and/or an effect of the layer to lower the resistance when the growth units of calcium phosphate incorporate into the growing island. These results indicate that the crystallized 45S5 BG is suitable to be used as a filler for polymeric matrix bioactive composites, as it maintains a high bioactivity associated with a stiffer behavior (as compared to standard BG).

Accuracy of diagnoses of HIV-related oral lesions by medical clinicians. Findings from the Women's Interagency HIV Study

OBJECTIVE

To determine if medical clinicians are as accurate as dental clinicians in recognizing diagnostic characteristics of HIV-related oral lesions.

METHODS

In 355 HIV-infected participants at five Women's Interagency HIV Study sites, we paired oral examinations conducted within 7 days of each other by dental and medical clinicians. We used the former as a gold standard against which to evaluate the accuracy of the latter. We assessed the accuracy of the medical clinicians' findings based both on their observations of abnormalities and on their descriptions of these abnormalities.

RESULTS

Dental clinicians diagnosed some oral abnormality in 38% of participants. When "abnormality" was used as the medical clinicians' outcome, sensitivities were 75% for pseudomembranous candidiasis and 58% for erythematous candidiasis, but only 40% for hairy leukoplakia. When a precise description of the abnormality was used as their outcome, sensitivities were 19%, 12% and 20%, respectively.

CONCLUSIONS

Medical clinicians recognize that HIV-related oral abnormalities are present in 40-75% of cases, but less often describe them accurately. Low sensitivity implies that the true associations of specific oral lesions with other HIV phenomena, such as time until AIDS, must be stronger than the literature suggests.

HIV-related oral manifestations among adolescents in a multicenter cohort study

PURPOSE

To describe baseline prevalence of oral mucosal diseases among HIV infected adolescents in relationship to biological and behavioral risk factors.

METHODS

Participants in Reaching for Excellence in Adolescent Care and Health (REACH), a multicenter longitudinal observational study of HIV/AIDS in adolescents, received physical examinations, blood tests, and oral examinations at 3-month intervals. We evaluated participants for oral conditions commonly seen in relationship to HIV, and explored the association of the most common lesion with selected biological and behavioral variables at baseline using contingency tables and Fisher's Exact test.

RESULTS

Among 294 HIV infected adolescents recruited between March 1996 and March 1999, the majority were female (75%), aged 17 to 18 years (69%), and African-American (73%). More than 90% had a CD4(+) T-lymphocyte count > 200 cells/mm(3) at baseline and 57% had a plasma HIV-1 RNA concentration <or=5000 copies/mL. The most common condition was oral candidiasis (6%), predominantly the pseudomembranous type. The only variable found to be associated with oral candidiasis was elevated plasma HIV-1 RNA concentration (p = .03). Aside from 2 cases of hairy leukoplakia and aphthous ulcers, no other oral mucosal lesions were identified in this subject population with apparently early HIV disease.

CONCLUSION

Similar types of oral lesions were observed in HIV infected adolescents as have been seen in adults, although the prevalence of these lesions was low. Elevated plasma HIV-1 RNA concentration was found to be associated with the baseline prevalence of oral candidiasis, and appeared to be a better predictor of HIV-related oral disease than CD4(+) T cell count in this cohort at early stage of HIV disease.

Multiple bone morphogenetic protein 1-related mammalian metalloproteinases process pro-lysyl oxidase at the correct physiological site and control lysyl oxidase activation in mouse embryo fibroblast cultures

Lysyl oxidase catalyzes the final enzymatic step required for collagen and elastin cross-linking in extracellular matrix biosynthesis. Pro-lysyl oxidase is processed by procollagen C-proteinase activity, which also removes the C-propeptides of procollagens I-III. The Bmp1 gene encodes two procollagen C-proteinases: bone morphogenetic protein 1 (BMP-1) and mammalian Tolloid (mTLD). Mammalian Tolloid-like (mTLL)-1 and -2 are two genetically distinct BMP-1-related proteinases, and mTLL-1 has been shown to have procollagen C-proteinase activity. The present study is the first to directly compare pro-lysyl oxidase processing by these four related proteinases. In vitro assays with purified recombinant enzymes show that all four proteinases productively cleave pro-lysyl oxidase at the correct physiological site but that BMP-1 is 3-, 15-, and 20-fold more efficient than mTLL-1, mTLL-2, and mTLD, respectively. To more directly assess the roles of BMP-1 and mTLL-1 in lysyl oxidase activation by connective tissue cells, fibroblasts cultured from Bmp1-null, Tll1-null, and Bmp1/Tll1 double null mouse embryos, thus lacking BMP-1/mTLD, mTLL-1, or all three enzymes, respectively, were assayed for lysyl oxidase enzyme activity and for accumulation of pro-lysyl oxidase and mature approximately 30-kDa lysyl oxidase. Wild type cells or cells singly null for Bmp1 or Tll1 all produced both pro-lysyl oxidase and processed lysyl oxidase at similar levels, indicating apparently normal levels of processing, consistent with enzyme activity data. In contrast, double null Bmp1/Tll1 cells produced predominantly unprocessed 50-kDa pro-lysyl oxidase and had lysyl oxidase enzyme activity diminished by 70% compared with wild type, Bmp1-null, and Tll1-null cells. Thus, the combination of BMP-1/mTLD and mTLL-1 is shown to be responsible for the majority of processing leading to activation of lysyl oxidase by murine embryonic fibroblasts, whereas in vitro studies identify pro-lysyl oxidase as the first known substrate for mTLL-2.

A comparison of the affective state and quality of life of chemotherapy patients who do and do not develop chemotherapy-induced oral mucositis

The purpose of this longitudinal study was to compare the quality of life and affective state of patients receiving chemotherapy who developed oral mucositis to patients who did not. Outpatients had their mouths assessed at the beginning of their chemotherapy, completed the Multidimensional Quality of Life scale, Cancer version (MQOLS-CA) and the Profile of Mood States (POMS). Patients again completed the MQOLS-CA and POMS if they developed mucositis during their three cycles (monthly), or if they did not and were exiting the study. Seventy-seven outpatients completed the study; 28 patients developed mucositis and 49 did not. The MQOLS-CA total scores for the entire sample decreased significantly over time (F(1,75) = 25.44, P < 0.001), but there was no group by time interaction, i.e., the change in MQOLS-CA total scores did not depend on mucositis status. While the POMS Total Mood Disturbance scores for the entire sample increased significantly over time (F(1,75) = 19.55, P < 0.001), there was a significant group by time interaction (F(1,75)= 4.85, P = 0.03). Patients who developed mucositis had a significant increase in mood disturbance compared to patients who did not. Further, the POMS subscales of depression and anger showed the same pattern of significant increases. In conclusion, the development of mucositis adversely affected the outpatients' affective states, but not their QOL.

Mutational analysis of the BMP-1 gene in patients with gastroschisis

BACKGROUND

Gastroschisis is a rare abdominal wall defect. Although the pathogenesis of gastroschisis is unknown, there is some evidence of the genetic etiology of gastroschisis. Recently, a functionally null deletion of the mouse bone morphogenic protein-1 (BMP-1) gene resulted in a phenotype that resembled a human neonate with gastroschisis. BMP-1 thus became the first potential candidate gene for gastroschisis.

METHODS

To explore this possibility the authors collected blood samples from 11 patients who had gastroschisis. Mutational analysis of exons 2 to 15 of the human BMP-1 gene was performed using genomic polymerase chain reaction, single-strand conformation polymorphism analysis and direct sequencing methods.

RESULTS

No mutation of the human BMP-1 gene was observed in any of these patients.

CONCLUSION

Although heterogeneous etiologies might be proposed for gastroschisis, our results provide further evidence of a nongenetic etiology for gastroschisis. J Pediatr Surg 36:885-887.

Effect of highly active antiretroviral therapy on frequency of oral warts

To investigate changes in the pattern of oral disease associated with highly active antiretroviral therapy (HAART), we assessed the frequency of these lesions in our clinic over 9 years. We retrospectively studied 1280 patients seen between July, 1990, and June, 1999, and related oral findings to medication use, immune function, and viral load. We found significant decreases in oral candidosis, hairy leucoplakia, and Kaposi's sarcoma over time, but no change in the occurrence of aphthous ulcers. There was an increase in salivary-gland disease and a striking increase in warts: three-fold for patients on antiretroviral therapy and six-fold for those on HAART (p=0.01). This pattern of oral disease in a referral clinic suggests that an increase in oral warts could be occurring as a complication of HAART.

Homologues of Twisted gastrulation are extracellular cofactors in antagonism of BMP signalling

Twisted gastrulation (TSG) is involved in specifying the dorsal-most cell fate in Drosophila embryos, but its mechanism of action is poorly understood. TSG has been proposed to modify the action of Short gastrulation (SOG), thereby increasing signalling by the bone morphogenetic protein (BMP) Decapentaplegic. SOG, an inhibitor of BMP signalling, is in turn inactivated by the protease Tolloid. Here we identify Tsg gene products from human, mouse, Xenopus, zebrafish and chick. Expression patterns in mouse and Xenopus embryos are consistent with in vivo interactions between Tsg, BMPs and the vertebrate SOG orthologue, chordin. We show that Tsg binds both the vertebrate Decapentaplegic orthologue BMP4 and chordin, and that these interactions have multiple effects. Tsg increases chordin's binding of BMP4, potentiates chordin's ability to induce secondary axes in Xenopus embryos, and enhances chordin cleavage by vertebrate tolloid-related proteases at a site poorly used in Tsg's absence; also, the presence of Tsg enhances the secondary axis-inducing activity of two products of chordin cleavage. We conclude that Tsg acts as a cofactor in chordin's antagonism of BMP signalling.

Bioactive glass stimulates in vitro osteoblast differentiation and creates a favorable template for bone tissue formation

In this study, we have investigated the behavior of fetal rat osteoblasts cultured on bioactive glasses with 55 wt% silica content (55S) and on a bioinert glass (60S) used either in the form of granules or in the form of disks. In the presence of Bioglass granules (55 wt% silica content), phase contrast microscopy permitted step-by-step visualization of the formation of bone nodules in contact with the particles. Ultrastructural observations of undecalcified sections revealed the presence of an electron-dense layer composed of needle-shaped crystals at the periphery of the material that seemed to act as a nucleating surface for biological crystals. Furthermore, energy dispersive X-ray (EDX) analysis and electron diffraction patterns showed that this interface contains calcium (Ca) and phosphorus (P) and was highly crystalline. When rat bone cells were cultured on 55S disks, scanning electron microscopic (SEM) observations revealed that cells attached, spread to all substrata, and formed multilayered nodular structures by day 10 in culture. Furthermore, cytoenzymatic localization of alkaline phosphatase (ALP) and immunolabeling with bone sialoprotein antibody revealed a positive staining for the bone nodules formed in cultures on 55S. In addition, the specific activity of ALP determined biochemically was significantly higher in 55S cultures than in the controls. SEM observations of the material surfaces after scraping off the cell layers showed that mineralized bone nodules remained attached on 55S surfaces but not on 60S. X-ray microanalysis indicated the presence of Ca and P in this bone tissue. The 55S/bone interfaces also were analyzed on transverse sections. The interfacial analysis showed a firm bone bonding to the 55S surface through an intervening apatite layer, confirmed by the X-ray mappings. All these results indicate the importance of the surface composition in supporting differentiation of osteogenic cells and the subsequent apposition of bone matrix allowing a strong bond of the bioactive materials to bone.

Factors influencing oral mucositis in patients receiving chemotherapy

PURPOSE

Oral mucositis is a painful complication of chemotherapy and can greatly affect patients' morbidity and mortality. Findings from two previous studies suggested a decrease in the prevalence of chemotherapy-induced mucositis in patients with solid tumors. The purposes of this study were to follow a large cohort of outpatients to determine the prevalence of mucositis and to identify whether certain clinical factors were significant in the development of mucositis.

DESCRIPTION OF STUDY

In this prospective study, a convenience sample of 199 outpatients was followed for three cycles or until mucositis developed. The clinical factors monitored included the following: pretreatment dental examination/repair; initial standard chemotherapy dosage; prophylactic use of colony-stimulating factors; and use of preventive mouthwashes or other prophylactic measures.

RESULTS

Oral mucositis developed in 50 patients (25.1%). Prechemotherapy dental examination/repair and initial standard chemotherapy dosage were equivalent among both groups. Of the 48 patients in whom mucositis developed, 10 (20.8%) received prophylactic colony-stimulating factors. Of 134 patients in whom mucositis did not develop, 46 (34.3%) received prophylactic colony-stimulating factors. This difference was statistically nonsignificant.

CLINICAL IMPLICATIONS

Differences in the clinical factors investigated could not explain the lower prevalence of oral mucositis among the current patient cohort. The reason for the diminishing prevalence of this side effect remains unclear, and additional parameters, particularly detailed oral hygiene practices, should be evaluated. In the meantime, oncology clinicians should consider the teaching of patients and urging them to use good oral hygiene practices as necessary and potentially preventive measures against chemotherapy-induced mucositis.

Bone morphogenetic protein-1 processes probiglycan

Bone morphogenetic protein-1 (BMP-1) is a metalloprotease that plays important roles in regulating the deposition of fibrous extracellular matrix in vertebrates, including provision of the procollagen C-proteinase activity that processes the major fibrillar collagens I-III. Biglycan, a small leucine-rich proteoglycan, is a nonfibrillar extracellular matrix component with functions that include the positive regulation of bone formation. Biglycan is synthesized as a precursor with an NH(2)-terminal propeptide that is cleaved to yield the mature form found in vertebrate tissues. Here, we show that BMP-1 cleaves probiglycan at a single site, removing the propeptide and producing a biglycan molecule with an NH(2) terminus identical to that of the mature form found in tissues. BMP-1-related proteases mammalian Tolloid and mammalian Tolloid-like 1 (mTLL-1) are shown to have low but detectable levels of probiglycan-cleaving activity. Comparison shows that wild type mouse embryo fibroblasts (MEFs) produce only fully processed biglycan, whereas MEFs derived from embryos homozygous null for the Bmp1 gene, which encodes both BMP-1 and mammalian Tolloid, produce predominantly unprocessed probiglycan, and MEFs homozygous null for both the Bmp1 gene and the mTLL-1 gene Tll1 produce only unprocessed probiglycan. Thus, all detectable probiglycan-processing activity in MEFs is accounted for by the products of these two genes.

Effect of premedication guidelines and leukoreduction on the rate of febrile nonhaemolytic platelet transfusion reactions

Platelet transfusion reactions were prospectively studied in haematology/oncology patients at five university teaching hospitals over three consecutive summers. The initial summer study provided baseline information on the use of premedications and the rate of platelet transfusion reactions (fever, chills, rigors and hives). Most (73%) platelet recipients were premedicated and 30% (95% CI 28-33%) of transfusions were complicated by reactions. The second study followed implementation of guidelines for premedicating platelet transfusions. Despite a marked reduction in premedication (50%), there was little change in the platelet transfusion reaction rate, 26% (95% CI 24-29%), or the type of reactions. The third study followed implementation of prestorage platelet leukoreduction while maintaining the premedication guidelines. The reaction rate decreased to 19% (95% CI 17-22%). For nonleukoreduced platelets, there was a statistically significant association between the platelet age and reaction rate (P = 0.04). For leukoreduced platelets, there was no statistically significant association between platelet age and reaction rate (P = 0.5). Plasma reduction of nonleukoreduced platelet products also reduced the reaction rate. These prospective studies document a high rate of platelet transfusion reactions in haematology/oncology patients and indicate premedication use can be reduced without increasing the reaction rate. Prestorage leukoreduction and/or plasma reduction of platelet products reduces but does not eliminate febrile nonhemolytic platelet transfusion reactions.

Oral mucosal lesions and HIV viral load in the Women's Interagency HIV Study (WIHS)

The prevalence of oral lesions was assessed in a five-center subset of the Women's Interagency HIV Study (WIHS) and correlated with other features of HIV disease. Oral examinations were performed by dental examiners on 729 women (577 HIV-positive and 152 HIV-negative) during baseline examination. Significant differences between the groups were found for the following oral lesions: pseudomembranous candidiasis, 6.1% and 2.0%, respectively; erythematous candidiasis, 6.41% and 0.7%, respectively; all oral candidiasis, pseudomembranous and/or erythematous, 13.7% and 3.3%, respectively. Hairy leukoplakia was observed in 6.1% of HIV-positive women. No significant differences were found for recurrent aphthous ulcers, herpes simplex lesions, or papillomas. Kaposi's sarcoma was seen in 0.5% of HIV-positive and 0% of HIV-negative women. Using multiple logistic regression models controlling for use of antiretrovirals and antifungals, in HIV-positive women the presence of oral candidiasis was associated with a CD4 count <200 cells/microl, cigarette smoking, and heroin/methadone use; the presence of hairy leukoplakia was not related to CD4 count but was associated with high viral load. Oral candidiasis and hairy leukoplakia are confirmed as being common features of HIV infection in women and appear to be associated with HIV viral load, immunosuppression, and various other behaviorally determined variables.

Bone morphogenetic protein 1 is an extracellular processing enzyme of the laminin 5 gamma 2 chain

Epithelial cells maintained in culture medium containing low calcium proteolytically process laminin 5 (alpha3beta3gamma2) within the alpha3 and gamma2 chains (). Experiments were designed to identify the enzyme(s) responsible for the laminin 5 processing and the sites of proteolytic cleavage. To characterize the nature of laminin 5 processing, we determined the N-terminal amino acid sequences of the proteolytic fragments produced by the processing events. The results indicate that the first alpha3 chain cleavage (200-l65 kDa alpha3) occurs within subdomain G4 of the G domain. The second cleavage (l65-l45 kDa alpha3) occurs within the lIla domain, 11 residues N-terminal to the start of domain II. The gamma chain is cleaved within the second epidermal growth factor-like repeat of domain Ill. The sequence cleaved within the gamma2 chain matches the consensus sequence for the cleavage of type I, II, and III procollagens by bone morphogenetic protein-1 (BMP-1), also known as type I procollagen C-proteinase (). Recombinant BMP-1 cleaves gamma2 in vitro, both within intact laminin 5 and at the predicted site of a recombinant gamma2 short arm. alpha3 is also cleaved by BMP-1 in vitro, but the cleavage site is yet to be determined. These results show the laminin alpha3 and gamma2 chains to be substrates for BMP-1 in vitro. We speculate that gamma2 cleavage is required for formation of the laminin 5-6 complex and that this complex is directly involved in assembly of the interhemidesmosomal basement membrane. This further suggests that BMP-1 activity facilitates basement membrane assembly, but not hemidesmosome assembly, in the laminin 5-rich dermal-epidermal junction basement membrane in vivo.

The prevalence of xerostomia and salivary gland hypofunction in a cohort of HIV-positive and at-risk women

The association of xerostomia and salivary gland hypofunction with HIV infection has been established for men but not for women. We investigated the prevalence of these conditions in a national cohort (n = 733) of HIV-positive and at-risk HIV-negative women. Participants in this prospective cross-sectional study were recruited from the Women's Interagency HIV Study (WIHS) at five outpatient USA clinics. Xerostomia was assessed based on "yes" responses to a dry-mouth questionnaire. Samples of unstimulated whole and chewing-stimulated whole saliva were collected under standardized conditions. The major salivary glands were also evaluated clinically. The prevalence of dry-mouth complaint, the absence of saliva upon palpation, and zero unstimulated whole saliva (flow rate = 0 mL/min) were significantly (p = 0.001) higher in HIV-positive women. Adjusted odds of zero unstimulated whole saliva were significantly (p = 0.02) higher in HIV-positive women vs. HIV-negative women (OR = 2.86; 95% CI, 1.23 to 6.63). Significant (p = 0.03) univariate association was found between zero unstimulated whole saliva and CD4 counts. Adjusted odds of zero unstimulated whole saliva were significantly (p = 0.02) higher for HIV-positive women with CD4 < 200 compared with those with CD4 > 500 (OR = 2.61; 95% CI, 1.17 to 5.85). Chewing-stimulated flow rates were not significantly different between seropositive and seronegative women. The prevalence of xerostomia and salivary gland hypofunction appears to be significantly higher in HIV-positive women relative to a comparable group of at-risk seronegative women. Immunosuppression levels measured by CD4 cell counts are significantly associated with xerostomia and salivary gland hypofunction in a population of HIV-positive women.

Randomized clinical trial of the effectiveness of 3 commonly used mouthwashes to treat chemotherapy-induced mucositis

OBJECTIVE

To test the effectiveness of 3 mouthwashes used to treat chemotherapy-induced mucositis. The mouthwashes were as follows: salt and soda, chlorhexidine, and "magic" mouthwash (lidocaine, Benadryl, and Maalox).

STUDY DESIGN

A randomized, double-blind clinical trial was implemented in 23 outpatient and office settings. Participants were monitored from the time they developed mucositis until cessation of the signs and symptoms of mucositis, or until they finished their 12-day supply of mouthwash. All participants followed a prescribed oral hygiene program and were randomly assigned a mouthwash. Nurses used the Oral Assessment Guide for initial assessment and taught patients how to assess their own mouths, then phoned the patients every other day to gather status reports.

RESULTS

In 142 of 200 patients, there was a cessation of the signs and symptoms of mucositis within 12 days. No significant differences in time for the cessation of the signs and symptoms were observed among the 3 groups.

CONCLUSIONS

Given the comparable effectiveness of the mouthwashes, the least costly was salt and soda mouthwash.

Strategy for identification of sequence variants in COL7A1 and a novel 2-bp deletion mutation in recessive dystrophic epidermolysis bullosa

The diagnostic hallmark of the dystrophic forms of epidermolysis bullosa (DEB), a group of heritable blistering skin diseases, is abnormalities in the anchoring fibrils at the dermal-epidermal basement membrane zone. Since type VII collagen is the major, if not the exclusive, component of the anchoring fibrils, the corresponding gene (COL7A1) is the candidate gene in DEB. Recent cloning of the type VII collagen cDNA and elucidation of the exon-intron organization of the gene have provided the basis for us to develop a novel strategy for identification of sequence variants in COL7A1. Optimization of 72 balanced primer pairs corresponding to flanking intronic sequences allowed PCR amplification of all 118 exons directly from genomic DNA. The PCR products were examined by heteroduplex analysis followed by comparative nucleotide sequencing. More than 100 sequence variants have been identified thus far in COL7A1 using this method, some of which are single base pair polymorphisms and many of which are pathogenetic mutations contributing to the blistering phenotype in DEB. The comprehensive method described is useful for rapid, reliable, and sensitive detection of sequence variants in COL7A1. We demonstrate the utility of this novel strategy in mutation detection and prenatal exclusion of RDEB in a consanguineous family at risk for recurrence.

Null alleles of the COL5A1 gene of type V collagen are a cause of the classical forms of Ehlers-Danlos syndrome (types I and II)

Ehlers-Danlos syndrome (EDS) types I and II, which comprise the classical variety, are well characterized from the clinical perspective, but it has been difficult to identify the molecular basis of the disorder in the majority of affected individuals. Several explanations for this failure to detect mutations have been proposed, including genetic heterogeneity, failure of allele expression, and technical difficulties. Genetic heterogeneity has been confirmed as an explanation for such failure, since causative mutations have been identified in the COL5A1, COL5A2, and tenascin X genes and since they have been inferred in the COL1A2 gene. Nonetheless, in the majority of families with autosomal dominant inheritance of EDS, there appears to be linkage to loci that contain the COL5A1 or COL5A2 genes. To determine whether allele-product instability could explain failure to identify some mutations, we analyzed polymorphic variants in the COL5A1 gene in 16 individuals, and we examined mRNA for the expression of both alleles and for alterations in splicing. We found a splice-site mutation in a single individual, and we determined that, in six individuals, the mRNA from one COL5A1 allele either was not expressed or was very unstable. We identified small insertions or deletions in five of these cell strains, but we could not identify the mutation in the sixth individual. Thus, although as many as one-half of the mutations that give rise to EDS types I and II are likely to lie in the COL5A1 gene, a significant portion of them result in very low levels of mRNA from the mutant allele, as a consequence of nonsense-mediated mRNA decay.

Salivary gland disease in human immunodeficiency virus-positive women from the WIHS study. Women's Interagency HIV Study

OBJECTIVE

To determine the prevalence of enlargement, tenderness, and absence of saliva on palpation as indicators of salivary gland disease in women who are human immunodeficiency virus (HIV)-positive.

STUDY DESIGN

The study subjects are participants in the Women's Interagency HIV Study (WIHS), a multicenter study examining HIV-seropositive women and at-risk HIV-seronegative women. A total of 576 HIV-positive women and 152 HIV-negative women were examined at their baseline oral visit for clinical markers of salivary gland disease. Viral load levels, CD4 counts, and CD8 counts were obtained as part of the related core study.

RESULTS

HIV-positive women had higher rates of salivary gland enlargement (4.3%), tenderness (6.9%), and absence of saliva on palpation (26.6%) compared with HIV-negative women, who had rates of 1.3%, 4.6%, and 13.2%, respectively. Absence of saliva was significantly different (P =. 001) between the 2 groups. When 2 of the 3 clinical findings were combined, comparisons between the HIV-positive women and HIV-negative women became significant at the P <.05 level for every combination, except for enlargement/tenderness for the submandibular/sublingual gland. For the HIV-positive women, the viral load was significantly related to enlargement (P =.019) and enlargement/absence of saliva on palpation (P =.037) for the parotids and enlargement (P =.046), absence of saliva (P =.043), and enlargement/absence of saliva (P =.022) for the submandibular/sublingual glands. Significant linear trends were found for increasing viral load and enlargement (P =.013) and enlargement/tenderness (P =.024) for the submandibular/sublingual glands. Significance was present for submandibular/sublingual absence of saliva and tenderness/absence of saliva for CD4 and CD8 medians.

CONCLUSIONS

Serostatus is related to salivary gland disease as assessed by glandular enlargement, tenderness, and absence of saliva on palpation. Furthermore, our findings indicate that a multidimensional approach to gland assessment may provide a more complete and perhaps more adequate description of glandular involvement with HIV infection.

Spatiotemporal expression patterns of mammalian chordin during postgastrulation embryogenesis and in postnatal brain

Chordin is an antagonist of TGFbeta-like bone morphogenetic proteins (BMPs) that plays roles in dorsoventral axis formation and in induction, maintenance and/or differentiation of neural tissue in early vertebrate embryogenesis. In contrast, little is known concerning possible roles for Chordin at later stages of vertebrate development and in the adult. To provide insights into possible postgastrulation roles for Chordin, we report the spatiotemporal expression patterns of Chordin in 8.5- to 15.5-dpc mouse embryos and in the postnatal mouse brain. Expression of Chordin in the primordia of most major organs from 10.5 dpc, including the brain, lung, heart, liver, kidney, thymus, and gut, suggests multiple functions for Chordin in organogenesis, potentially by means of interactions with TGFbeta-like BMPs. The relatively high levels of Chordin expression in condensing and differentiating cartilage elements from 11.5 dpc indicates a generalized role for Chordin throughout embryonic skeletogenesis. In the postnatal mouse brain, we demonstrate that Chordin is coexpressed with other components of the TGFbeta-like BMP signalling pathway in the cerebellum and hippocampus, sites of high synaptic plasticity, suggesting a role for Chordin in this process.

The pro-alpha3(V) collagen chain. Complete primary structure, expression domains in adult and developing tissues, and comparison to the structures and expression domains of the other types V and XI procollagen chains

The low abundance fibrillar collagen type V is widely distributed in tissues as an alpha1(V)(2)alpha2(V) heterotrimer that helps regulate the diameters of fibrils of the abundant collagen type I. Mutations in the alpha1(V) and alpha2(V) chain genes have been identified in some cases of classical Ehlers-Danlos syndrome (EDS), in which aberrant collagen fibrils are associated with connective tissue fragility, particularly in skin and joints. Type V collagen also exists as an alpha1(V)alpha2(V)alpha3(V) heterotrimer that has remained poorly characterized chiefly due to inability to obtain the complete primary structure or nucleic acid probes for the alpha3(V) chain or its biosynthetic precursor, pro-alpha3(V). Here we provide human and mouse full-length pro-alpha3(V) sequences. Pro-alpha3(V) is shown to be closely related to the alpha1(V) precursor, pro-alpha1(V), but with marked differences in N-propeptide sequences, and collagenous domain features that provide insights into the low melting temperature of alpha1(V)alpha2(V)alpha3(V) heterotrimers, lack of heparin binding by alpha3(V) chains and the possibility that alpha1(V)alpha2(V)alpha3(V) heterotrimers are incorporated into heterotypic fibrils. In situ hybridization of mouse embryos detects alpha3(V) expression primarily in the epimysial sheaths of developing muscles and within nascent ligaments adjacent to forming bones and in joints. This distribution, and the association of alpha1(V), alpha2(V), and alpha3(V) chains in heterotrimers, suggests the human alpha3(V) gene COL5A3 as a candidate locus for at least some cases of classical EDS in which the alpha1(V) and alpha2(V) genes have been excluded, and for at least some cases of the hypermobility type of EDS, a condition marked by gross joint laxity and chronic musculoskeletal pain. COL5A3 is mapped to 19p13.2 near a polymorphic marker that should be useful in analyzing linkage with EDS and other disease phenotypes.

Post-translational proteolytic processing of procollagen C-terminal proteinase enhancer releases a metalloproteinase inhibitor

Activity of matrix metalloproteinases (MMP) is regulated by a family of proteins called tissue inhibitors of metalloproteinases (TIMP). Four TIMPs have been cloned, and their molecular weights range from 29,000 to 20,000. By reverse zymography, we have observed a metalloproteinase inhibitor with an apparent molecular weight of 16, 500 from medium conditioned by human brain tumor cells. Antibodies directed against TIMPs failed to react with the 16,500 molecular weight inhibitor, indicating that it was not a truncated form of a known TIMP. The inhibitor was isolated from conditioned medium using affinity and ion exchange chromatography. N-terminal sequences of the inhibitor matched amino acid sequences within the C-terminal domain of a protein known as procollagen C-terminal proteinase enhancer (PCPE). Thus, the inhibitor was named CT-PCPE. Comparison of the N-terminal domain of TIMP with CT-PCPE revealed that both contained six cysteine residues. As in the case of TIMP, reduction and alkylation abolished the inhibitory activity of CT-PCPE. Purified CT-PCPE inhibited MMP-2 with an IC(50) value much greater than that of TIMP-2. This implies that MMPs may not be the physiologic targets for CT-PCPE inhibition. However, these results suggest that CT-PCPE may constitute a new class of metalloproteinase inhibitor.

Histologic observations of periodontal wound healing after treatment with PerioGlas in nonhuman primates

The effect of PerioGlas (synthetic bone particulate) on wound healing of experimental palatal periodontal defects in monkeys was evaluated. Chronic periodontal defects were created on the palatal aspects of maxillary molars and premolars. Open-flap debridement was performed. Experimental sites received PerioGlas, while control sites received no further treatment. Histologic measurements were performed on new bone, new cementum, epithelial downgrowth, and recession. Results showed significantly more new cementum and less epithelial downgrowth in the sites that received PerioGlas (P < 0.05). The present results indicate that PerioGlas may enhance periodontal wound healing outcomes.

Mammalian BMP-1/Tolloid-related metalloproteinases, including novel family member mammalian Tolloid-like 2, have differential enzymatic activities and distributions of expression relevant to patterning and skeletogenesis

Vertebrate bone morphogenetic protein 1 (BMP-1) and Drosophila Tolloid (TLD) are prototypes of a family of metalloproteases with important roles in various developmental events. BMP-1 affects morphogenesis, at least partly, via biosynthetic processing of fibrillar collagens, while TLD affects dorsal-ventral patterning by releasing TGFbeta-like ligands from latent complexes with the secreted protein Short Gastrulation (SOG). Here, in a screen for additional mammalian members of this family of developmental proteases, we identify novel family member mammalian Tolloid-like 2 (mTLL-2) and compare enzymatic activities and expression domains of all four known mammalian BMP-1/TLD-like proteases [BMP-1, mammalian Tolloid (mTLD), mammalian Tolloid-like 1 (mTLL-1), and mTLL-2]. Despite high sequence similarities, distinct differences are shown in ability to process fibrillar collagen precursors and to cleave Chordin, the vertebrate orthologue of SOG. As previously demonstrated for BMP-1 and mTLD, mTLL-1 is shown to specifically process procollagen C-propeptides at the physiologically relevant site, while mTLL-2 is shown to lack this activity. BMP-1 and mTLL-1 are shown to cleave Chordin, at sites similar to procollagen C-propeptide cleavage sites, and to counteract dorsalizing effects of Chordin upon overexpression in Xenopus embryos. Proteases mTLD and mTLL-2 do not cleave Chordin. Differences in enzymatic activities and expression domains of the four proteases suggest BMP-1 as the major Chordin antagonist in early mammalian embryogenesis and in pre- and postnatal skeletogenesis.

Chemokine gene expression in human oral mucosa

In order to gain further understanding of the role of chemokines in healthy oral mucosa, we analyzed mRNA expression of the alpha (CXC)-family chemokines IL-8 and GROgamma as well as of the beta (CC)-family chemokines MIP-1alpha, MIP-1beta and MCP-1 in twenty young and healthy subjects with good oral hygiene. Twenty biopsies were taken from clinically healthy oral mucosa before surgical removal of impacted wisdom teeth. In addition, five biopsies from patients presenting with specific oral lesions were studied. RNA was purified, quantitated and utilized as substrate for competitive reverse transcription-polymerase chain reaction (RT-PCR). In healthy tissue, IL-8 and MCP-1 mRNA was constitutively expressed in all biopsies, whereas GROgamma, MIP-1alpha, and MIP-1beta were significantly lower. These findings suggest that IL8 and MCP-1 play a significant role in oral tissue homeostasis. The few samples from pathological conditions encourage exploring diseased tissue in more detail.

Effect of receptive oral sex and smoking on the incidence of hairy leukoplakia in HIV-positive gay men

We sought to determine whether hairy leukoplakia (HL), an Epstein-Barr virus-related oral lesion, is associated with receptive oral sex activity and cigarette smoking among HIV-positive gay men. Oral examinations were conducted every 6 months among San Francisco Men's Health Study participants over a 6-year period. We fitted time-to-lesion regression models to compare the incidence of HL among men who had mouth-to-penis contact with various numbers of partners, while controlling for cigarette smoking and CD4 count. The 6-year incidence of HL was 32% among 291 HIV-positive men. We found no significant increase in the hazard of developing HL for each additional insertive-oral-sex male partner in the past 6 months (relative hazard = 1.01; 95% confidence interval [CI], 0.99, 1.02), and a similar lack of association when number of sex partners was categorized. However, the hazard of developing HL doubled with any 300-unit decrease in CD4 count (95% CI, 1.4, 2.7), or if men smoked > or =20 cigarettes/day compared with nonsmokers (95% CI, 1.2, 3.9). This finding, which may suggest one effect that smoking produces on the oral mucosa's local immune response, merits further investigation.

The mammalian Tolloid-like 1 gene, Tll1, is necessary for normal septation and positioning of the heart

Mammalian Tolloid-like 1 (mTLL-1) is an astacin-like metalloprotease, highly similar in domain structure to the morphogenetically important proteases bone morphogenetic protein-1 (BMP-1) and Drosophila Tolloid. To investigate possible roles for mTLL-1 in mammalian development, we have used gene targeting in ES cells to produce mice with a disrupted allele for the corresponding gene, Tll1. Homozygous mutants were embryonic lethal, with death at mid-gestation from cardiac failure and a unique constellation of developmental defects that were apparently confined solely to the heart. Constant features were incomplete formation of the muscular interventricular septum and an abnormal and novel positioning of the heart and aorta. Consistent with roles in cardiac development, Tll1 expression was specific to precardiac tissue and endocardium in 7.5 and 8.5 days p.c. embryos, respectively. Tll1 expression was also high in the developing interventricular septum, where expression of the BMP-1 gene, Bmp1, was not observed. Cardiac structures that were not affected in Tll1−/− embryos either showed no Tll1 expression (atrio-ventricular cushions) or showed overlapping expression of Tll1 and Bmp1 (aortico-pulmonary septum), suggesting that products of the Bmp1 gene may be capable of functionally substituting for mTLL-1 at sites in which they are co-expressed. Together, the various data show that mTLL-1 plays multiple roles in formation of the mammalian heart and is essential for formation of the interventricular septum.

Risk factors for chemotherapy-induced oral mucositis: dental appliances, oral hygiene, previous oral lesions, and history of smoking

Oral mucositis is one of the dose-limiting toxicities of several chemotherapy (CTX) agents. There are suggested risk factors that could influence the development of mucositis. The presence of dental appliances, history of oral lesions, or smoking have the potential to irritate the oral mucosa and produce breaks in the integrity of the mucosa. The purposes of this study were to determine if there were differences in the incidence, severity, and time to onset of CTX-induced mucositis in oncology outpatients who wore dental appliances, had a history of oral lesions, had varying oral hygiene/care practices, and had a history of smoking and those who did not. Patients who were initiated a course of CTX that included stomatotoxic agents were followed for three complete cycles of CTX. They were instructed on how to examine their mouths for mucositis, to contact, and then visit their outpatient settings if it occurred. Clinicians corroborated the presence of mucositis, and the Eiler's Oral Assessment Guide was used by clinicians to determine the severity. Of 332 outpatients, almost half (46%) wore some type of dental appliance, 32% had a history of oral lesions, 10% were currently smoking, and 63% had a history of smoking. Oral hygiene/care practices varied: 81% brushed their teeth two or more times a day, 29% flossed at least daily, 11% had visited their dentist within 2 months of beginning CTX, and 10% had their teeth professionally cleaned within two months of beginning CTX. There was a 31% (n = 104) incidence of CTX-induced mucositis. No significant differences were found in the incidence between patients who wore dental appliances, had a history of oral lesions, had a history of smoking, and practiced different hygiene/care and patients who did not. Of 104 patients who developed mucositis, the average severity rating was 13.05 +/- 2.88 (+/-SD) (a normal mouth is rated at 8) and the average time to onset was 22.3 +/- 21.46 days. There were no significant differences found in severity or time to onset of mucositis between patients who wore dental appliances, had a history of oral lesions, had a history of smoking, and practiced different dental hygiene/care and patients who did not. Although not significant, there were interesting differences in the time to onset across the suggested risk factors (e.g., patients who had visited a dentist or who had their teeth professionally cleaned within 2 months before beginning before CTX developed mucositis 7.4 and 10.6 days sooner, respectively, than patients who did not). These findings suggest that risk factors for the development of CTX-induced mucositis are not as simple and direct as clinicians may believe.

In vivo analysis of secreted aspartyl proteinase expression in human oral candidiasis

Secreted aspartyl proteinases are putative virulence factors in Candida infections. Candida albicans possesses at least nine members of a SAP gene family, all of which have been sequenced. Although the expression of the SAP genes has been extensively characterized under laboratory growth conditions, no studies have analyzed in detail the in vivo expression of these proteinases in human oral colonization and infection. We have developed a reliable and sensitive procedure to detect C. albicans mRNA from whole saliva of patients with oral C. albicans infection and those with asymptomatic Candida carriage. The reverse transcription-PCR protocol was used to determine which of the SAP1 to SAP7 genes are expressed by C. albicans during colonization and infection of the oral cavity. SAP2 and the SAP4 to SAP6 subfamily were the predominant proteinase genes expressed in the oral cavities of both Candida carriers and patients with oral candidiasis; SAP4, SAP5, or SAP6 mRNA was detected in all subjects. SAP1 and SAP3 transcripts were observed only in patients with oral candidiasis. SAP7 mRNA expression, which has never been demonstrated under laboratory conditions, was detected in several of the patient samples. All seven SAP genes were simultaneously expressed in some patients with oral candidiasis. This is the first detailed study showing that the SAP gene family is expressed by C. albicans during colonization and infection in humans and that C. albicans infection is associated with the differential expression of individual SAP genes which may be involved in the pathogenesis of oral candidiasis.

Structural organization and expression patterns of the human and mouse genes for the type I procollagen COOH-terminal proteinase enhancer protein

The procollagen C-proteinase enhancer (PCPE) is a glycoprotein that potentiates enzymatic cleavage of the type I procollagen C-propeptide by bone morphogenetic protein-1 (BMP-1). The human PCPE gene (PCOLCE) was previously mapped to 7q22, an area frequently disrupted in uterine leiomyomata, while disruption of the rat PCPE gene leads to anchorage-independent growth and loss of contact inhibition in rat fibroblasts. Here we describe the entire intron/exon organizations of PCOLCE and the mouse PCPE gene (Pcolce) and analyze expression of PCOLCE RNA in various human adult and fetal tissues and of Pcolce RNA at various stages of mouse development. PCOLCE and Pcolce are shown to be small genes 6.0 and 6.5 kb, respectively, with a conserved intron/exon structure comprising 9 exons. A notable difference between the two genes derives from insertion of multiple Alu sequences immediately upstream and downstream and within PCOLCE. Temporal expression of PCPE mRNA is shown to differ from that of BMP-1 and type I procollagen during mouse development, consistent with possible additional functions for PCPE beyond enhancement of C-proteinase activity. Consistent with a possible role in leiomyomata, PCOLCE is shown to be expressed at relatively high levels in uterus.

Oral health care issues in HIV disease: developing a core curriculum for primary care physicians

BACKGROUND

Given the high occurrence of oral manifestations in patients infected with human immunodeficiency virus (HIV), the relative ease in recognizing these manifestations on physical examination, and their potential impact on the health care and quality of life in these patients, it is critical to provide adequate training for primary care physicians in this area.

METHODS

Based on a review of the published literature and the consensus of a national panel of primary care physicians and dentists with clinical and research expertise in this area, a core curriculum was developed for primary care physicians regarding oral health care issues in HIV disease.

RESULTS AND CONCLUSIONS

We describe the process of developing the core curriculum of knowledge, skills, and attitudes regarding oral health care issues in HIV disease. The final curriculum is in a format that allows for easy accessibility and is organized in a manner that is clinically relevant for primary care physicians.