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Bruce J Baum

Publications and source records attributed to Bruce J Baum.

At least 37 records · Page 2Linked to original sources
PubMed2004

Etanercept in Sjögren's syndrome: a twelve-week randomized, double-blind, placebo-controlled pilot clinical trial.

OBJECTIVE: To assess the safety and potential efficacy of etanercept in the treatment of Sjögren's syndrome (SS). METHODS: This pilot study was a 12-week randomized, double-blind, placebo-controlled trial of etanercept, with 14 subjects in each group. Patients received 25 mg of etanercept or placebo (vehicle) by twice-weekly subcutaneous injection. Patients met the American-European Consensus Group criteria for SS. The primary outcome required at least 20% improvement from baseline values for at least 2 of the following 3 domains: subjective or objective measures of dry mouth, subjective or objective measures of dry eyes, and IgG level or erythrocyte sedimentation rate (ESR). RESULTS: Of the 14 patients taking etanercept, 11 had primary SS and 3 had SS secondary to rheumatoid arthritis. Baseline measures did not differ between the 2 groups. Three etanercept-treated patients and 1 placebo-treated patient did not complete the trial. Five etanercept-treated patients and 3 placebo-treated patients showed improvement from baseline in the primary outcome variable at 12 weeks, but the difference was not statistically significant. There were no significant differences between the groups for changes in subjective measures of oral or ocular symptoms (by visual analog scale), the IgG level, Schirmer I test result, van Bijsterveld score, or salivary flow. At 12 weeks, the ESR had decreased in the etanercept group compared with baseline (P = 0.004); however, the mean reduction was only 18.6%. CONCLUSION: We found no evidence to suggest that treatment with etanercept at a dosage of 25 mg twice weekly for 12 weeks was clinically efficacious in SS. A larger trial will be necessary to definitively address the efficacy of etanercept in the treatment of SS.

Arthritis, Rheumatoid↗
PubMed2004

Utilizing endocrine secretory pathways in salivary glands for systemic gene therapeutics.

Mammalian salivary glands are commonly used models of exocrine secretion. However, there is substantial experimental evidence showing the physiological existence of endocrine secretory pathways in these tissues. The use of gene transfer technology in vivo has allowed the unambiguous demonstration of these endocrine pathways. We and others have exploited such findings and evaluated salivary glands as possible target tissues for systemic applications of gene therapeutics. Salivary glands present numerous advantages for this purpose, including being well encapsulated, which limits extra-glandular vector dissemination, and having the luminal membranes of almost all parenchymal cells accessible via intraoral delivery of vectors through the main excretory ducts. Existing studies suggest that clinical benefits will result from salivary gland targeted systemic gene therapeutics.

Animals↗
PubMed2004

Developing a convenient large animal model for gene transfer to salivary glands in vivo.

BACKGROUND: Localized gene transfer to salivary glands has great potential for the treatment of salivary gland, systemic, and oral diseases. The minipig parotid gland, given its volume and morphological similarities to the human parotid gland, may be useful as a large animal model for pre-clinical gene transfer experiments. The purpose of this study was to perform an initial assessment of the efficacy and safety of adenoviral-vector-mediated gene transfer to parotid glands of miniature pigs. METHODS: AdCMVluc, a recombinant type 5 adenoviral (rAd5) vector containing a luciferase reporter gene, was administered to miniature pig parotid glands by intraductal cannulation. Five regions of gland tissue were obtained to measure the distribution of luciferase activity. The effects of time, viral dose, infusate buffer volume, and gland anatomical region on transgene expression were determined. Detailed serum chemistry and hematological analyses were performed. In addition, AdCMVlacZ, a similar rAd5 vector encoding beta-galactosidase, was also delivered to determine the parotid gland cell types transduced. RESULTS: Luciferase assays indicated that gene transfer to miniature pig salivary glands could be readily accomplished using rAd5 vectors. Highest transgene expression was found in the center of glands, which was > posterior > inferior > anterior > superior tissue regions. Expression was maximal on day 2 and declined to background by day 14, and observed in both acinar and ductal cells. Several serum chemistry and hematology parameters were transiently changed following rAd5 administration. CONCLUSIONS: Transgene expression by, and inflammatory response to, rAd5 vectors in minipig parotid glands are similar to results seen earlier in rodent studies. This suggests that results of salivary gland gene transfer from rodent studies can be extended to a larger animal model, and supports the value of using minipigs for pre-clinical applications of gene transfer to these tissues. Published in 2004 by John Wiley & Sons, Ltd.

Adenoviridae↗
PubMed2004

Salivary glands: novel target sites for gene therapeutics.

Directing the local or systemic expression of therapeutic proteins is a potentially important clinical application of gene transfer technology. Gene-based therapeutics theoretically offer many advantages over protein therapeutics. Numerous tissues have been evaluated for this purpose in animal models, most commonly the liver and skeletal muscle. Based on pre-clinical studies, we suggest that salivary glands are a valuable, yet under-appreciated, target tissue for both systemic and upper gastrointestinal tract gene therapeutic applications.

Animals↗
PubMed2004

Expanding horizons: modern science enters the mouth.

The purpose of this essay is to provide dentists with a brief overview of the unprecedented progress now being made in the biomedical sciences. Several examples are presented that show the potential of such advances to influence general and specialty practice over the next 10-25 years in prevention, diagnosis and treatment. It is important for dentists and dentistry to prepare for this occurrence.

Dentistry↗
PubMed2004

Centromere protein C is a target of autoantibodies in Sjögren's syndrome and is uniformly associated with antibodies to Ro and La.

OBJECTIVE: To determine which centromere proteins are recognized in Sjögren's syndrome (SS) and whether antibodies recognizing centromere proteins (CENP) B and CENP C identify a specific serologic subset. METHODS: Sera from 47 patients with SS, 12 xerostomic controls without SS, and 12 healthy controls were studied. All 47 patients met San Diego criteria for SS. Of these, 45 patients had primary SS and 2 had secondary SS with CREST. Sera were analyzed by immunoprecipitation of [35S] methionine-labeled Ro 52, La, and CENP B and C generated by coupled in vitro transcription/translation. Human salivary gland cells were also lysed and immunoprecipitated to determine antibody status against Ro 60. Serological and clinical profiles of patients recognizing CENP were defined. Proportions of sera recognizing CENP B, CENP C, Ro, or La across the 3 groups were compared using Fisher's exact test. RESULTS: Twenty-eight of 45 primary SS patients (62%) recognized Ro 52, and 24 patients (53%) recognized La. Ten of these 45 (22%) sera recognized CENP B or C. Furthermore, 7 of these 10 recognized exclusively CENP C; these 7 (100%) all tested positive for antibodies to both Ro 52 and La. This was in contrast to the group of SS patients that did not recognize CENP C alone, in whom anti-Ro 52 antibodies were found in 21 of 38 (55%; p = 0.034), and antibodies to La in 17 (45%; p = 0.01). Five of 7 CENP C positive sera were also positive for Ro 60. One of 3 patients with antibodies to CENP B also had antibodies to Ro 52, while none of these 3 had antibodies to La. Only patients with antibodies to CENP B showed a centromere pattern on immunofluorescence staining. CONCLUSION: Antibodies to both CENP B and CENP C occur in SS. In a subset representing 15% of SS patients studied, these anticentromere antibodies recognize exclusively CENP C, and were uniformly associated with antibodies to Ro 52 and La.

Antibodies, Antinuclear↗
PubMed2004

Will dentistry be left behind at the healthcare station?

The emerging opportunities for biological approaches to managing oral health were clearly apparent fifteen years ago. Responses in this direction have been tardy because of the economic prosperity of dental practice and the financial constraints on dental education. Representative existing and promising biology based technology is described. It is argued that education must be changed to teach the context and understanding of this technology. The alternative will be to concede important aspects of oral health care to physicians and others trained in their use.

Biological Therapy↗
PubMed2003

Advances in vector-mediated gene transfer.

Clinical applications of gene transfer technology initially targeted the treatment of inherited monogenetic disorders and cancers refractory to conventional therapies. Today, gene transfer approaches are being developed for most tissues and for multiple disorders including those affecting quality of life. The focus herein is eventual application of gene transfer technology for the management of organ-directed autoimmunity. A specific example is presented: Sjögren's syndrome and localized salivary gland gene transfer. The status of relevant pre-clinical gene transfer studies is reviewed, with an emphasis on use of adenoviral and adeno-associated viral vectors. Current limitations of effective organ-directed gene transfer are also discussed.

Adenoviridae↗
PubMed2003

Local adeno-associated virus-mediated interleukin 10 gene transfer has disease-modifying effects in a murine model of Sjögren's syndrome.

Female nonobese diabetic (NOD) mice develop spontaneous autoimmune sialadenitis and loss of salivary flow, and are a widely used model of Sjögren's syndrome. We examined the feasibility of local salivary gland immunomodulatory gene delivery to alter these sequelae in NOD mice. We constructed recombinant adeno-associated virus (rAAV) vectors encoding either human interleukin 10 (rAAVhIL-10) or beta-galactosidase (rAAVLacZ, control vector). Mice received rAAVhIL-10 or rAAVLacZ by retrograde submandibular ductal instillation either at age 8 weeks (early, before onset of sialadenitis), or at 16 weeks (late, after onset of sialadenitis). As a systemic treatment control, separate mice received intramuscular delivery of rAAVhIL-10 at each time point. Both submandibular and intramuscular delivery of vector led to low circulating levels of hIL-10. After submandibular administration of rAAVhIL-10, salivary flow rates at 20 weeks for both the early and late treatment groups were significantly higher than for both rAAVLacZ-administered and untreated mice. Systemic delivery of rAAVhIL-10 led to improved salivary flow in the late treatment group. Inflammatory infiltrates in submandibular glands, however, were significantly reduced only in mice receiving rAAVhIL-10 locally in the salivary gland compared with mice receiving this vector intramuscularly, or rAAVLacZ or no treatment. In addition, after submandibular rAAVhIL-10 delivery, NOD mice exhibited significantly lower blood glucose, and higher serum insulin, levels than all other groups, indicating some systemic benefit of this treatment. These studies show that expression of hIL-10 by rAAV vectors can have disease-modifying effects in the salivary glands of NOD mice, and suggest that local immunomodulatory gene transfer may be useful for managing the salivary gland pathology in Sjögren's syndrome.

Animals↗
PubMed2003

Inclusion of Moloney murine leukemia virus elements upstream of the transgene cassette in an E1-deleted adenovirus leads to an unusual genomic integration in epithelial cells.

Classically, the 5' and 3' long terminal repeats (LTRs) are considered necessary but not sufficient for retroviral integration. Recently, we reported that inclusion of these and additional elements from Moloney murine leukemia virus (MoMLV) facilitated transgene integration, without retroviral integrase, when placed in an adenoviral context (AdLTR-luc vector) (Nat. Biotech. 18 (2000), 176; Biochem. Biophys. Res. Commun. 300 (2003), 115). To help understand this nonhomologous DNA recombination event, we constructed another vector, AdELP-luc, with 2.7 kb of MoMLV elements identically placed into an E1-deleted adenovirus type 5 backbone upstream of a luciferase cDNA reporter gene. Unlike AdLTR-luc, no MoMLV elements were placed downstream of the expression cassette. AdELP-luc readily infected epithelial cells in vitro. Southern hybridizations with DNA from cloned cells showed that disruption of the MoMLV sequences occurred. One cell clone, grown in vitro without any special selection medium for 9 months, exhibited stable vector integration and luciferase activity. Importantly, both Southern hybridization and FISH analyses showed that in addition to the MoMLV elements and expression cassette, substantial adenoviral sequence downstream of the luciferase cDNA was genomically integrated. These results suggest that the 2.7 kb of MoMLV sequence included in AdELP-luc have cis-acting functions and mediates an unusual integration event.

Adenoviridae↗
PubMed2003

Differentiation of human bone marrow-derived cells into buccal epithelial cells in vivo: a molecular analytical study.

BACKGROUND: Adult bone marrow-derived (BMD) cells could be used to repair damaged organs and tissues, but the intrinsic plasticity of these cells has been questioned by results of in-vitro studies suggesting that such cells might fuse with other cells giving the appearance of differentiation. We aimed to determine whether fusion events are important in vivo. METHODS: To test whether BMD cells can colonise an epithelial tissue and differentiate there without fusion, we did in-situ hybridisation with Y and X chromosome probes labelled with 35-sulphur or digoxigenin, or labelled fluorescently. We did immunohistochemistry with anticytokeratin 13 along with fluorescence in-situ hybridisation to identify Y-chromosome positive buccal epithelial cells in cheek scrapings obtained from five females who had received either a bone-marrow transplant or an allogeneic mobilised peripheral-blood progenitor-cell transplant (enriched in CD34+ cells) from male donors. FINDINGS: When examined 4-6 years after male-to-female marrow-cell transplantation, all female recipients had Y-chromosome-positive buccal cells (0.8-12.7%). In more than 9700 cells studied, we detected only one XXXY-positive cell (0.01%) and one XXY cell (0.01%), both of which could have arisen when an XY cell fused with an XX cell. INTERPRETATION: Male BMD cells migrate into the cheek and differentiate into epithelial cells, an occurrence that does not depend on fusion of BMD cells to recipient cells. This finding might be an example of transdifferentiation of haemopoietic or stromal progenitor cells. Plasticity of BMD cells could be useful in regenerative medicine.

Adult↗
PubMed2003

Integration efficiency of a hybrid adenoretroviral vector.

The frequency with which the hybrid vector AdLTR-luc mediates genomic integration [Nat. Biotech. 18 (2000) 176-180] is unknown. To address this, we constructed AdLTR-red, using the AdLTR-luc backbone and the enhanced red fluorescence protein cDNA. Kinetic studies showed that AdLTR-red and a conventional adenoviral vector, AdCMV-red, entered and transduced epithelial cells comparably. AdLTR-red integration frequency in vitro, i.e., the percentage of red clones after 10-12 doubling times from limiting dilutions, was 8.0% (36/450; at 67 particles/cell). With AdCMV-red, 0/549 clones were integration-positive. Seven days after AdLTR-luc or AdCMV-luc (10(11) particles) femoral vein administration to adult rats splenocytes were prepared, stimulated with concanavalin A, and examined by FISH. AdLTR-luc integration occurred in 5-11% of mitotic rat splenocytes, while no unequivocal integration was found with AdCMV-luc. These data provide the first quantitative evidence of the frequency for genomic integration with this hybrid vector.

Adenoviridae↗
PubMed2003

Fungal load and candidiasis in Sjögren's syndrome.

OBJECTIVE: We sought to investigate the prevalence of Candida carriage and the relationships between salivary flow rates and oral Candida load in patients with Sjögren's syndrome (SS). METHODS: The oral Candida load of patients with SS was evaluated by culturing oral rinse (swish and spit) samples. Culture, Gram stain, and wet-mount test results were reported. RESULTS: One hundred three patients (96 women) met European criteria for SS (91 with primary SS and 12 with secondary SS). The mean age (95% confidence interval) was 55 years (range, 51-57 years). Oral rinse cultures were positive in 77% of subjects. The total stimulated salivary flow rate was inversely correlated with oral Candida load (r = -0.47; P </=.0001). The oral rinse samples yielded gram-positive results in 38% of patients with SS, and the Fungi-Fluor assay (wet mount) results were positive in 49%. CONCLUSIONS: The prevalence of Candida carriage varies according to the methods used to determine the presence of the organism and is similar to that reported in the literature. A low stimulated salivary flow rate-not a low unstimulated flow rate-was associated with Candida carriage.

Candida↗
PubMed2003

Distribution and toxicity resulting from adenoviral vector administration to a single salivary gland in adult rats.

BACKGROUND: We examined the distribution and toxicity associated with a single salivary gland administration of a recombinant adenoviral vector, AdCMVH3, encoding human histatin 3. METHODS: Adult rats received different doses of AdCMVH3 (0, 106, 3 x 107, and 109 pfu; 50 microl) via the right submandibular gland and were followed for 15 days. Food consumption, weight gain, clinical appearance, and serum chemistry were monitored, and a necropsy was performed. Vector distribution was examined by polymerase chain reaction, and selected saliva samples were tested for replication-competent adenovirus (RCA). RESULTS: All animals survived to sacrifice (days 2, 8, and 15), and appeared normal clinically. There were no differences in food consumption, weight gain, and serum chemistry. The only consistent necropsy findings were lymphoid infiltrates and necrosis in the target submandibular glands of high-dosage animals. AdCMVH3 detection was virus dose dependent, decreased with time, and at low dose preferentially observed in the targeted gland. No RCA was detected. CONCLUSIONS: Salivary gland administration of 109 pfu AdCMVH3 elicits an initial focal pathologic response and wide tissue distribution. There is no associated systemic toxicity up to 15 days, and lower doses are primarily found in glands.

Adenoviridae↗
PubMed2003

Sex steroid hormones in primary Sjögren's syndrome.

OBJECTIVE: To investigate the relationships between concentrations of sex hormones and measures of disease activity in patients with primary Sjögren's Syndrome (pSS). METHODS: Fifty-four women were evaluated: 39 patients (age, Q1,Q3: 57.0 yrs; 46, 66) diagnosed with pSS and 15 patients (49.0 yrs; 45, 60) who did not meet diagnostic criteria for pSS. The following measures of disease activity were assessed: serological data [antinuclear antibody, rheumatoid factor, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum immunoglobulin levels (IgG, IgA, IgM), serum protein, anti-SSA, and anti-SSB], labial minor salivary gland focus score, salivary flow rates, and objective measures of eye dryness (fluorescein corneal staining and unstimulated Schirmer's I test). Spearman correlations were calculated between these indices of disease activity and serum levels of sex hormones: dehydroepiandrosterone (DHEA), DHEA sulfate, androstenedione, testosterone, dihydrotestosterone (DHT), estrone, estradiol, and sex hormone binding globulin (SHBG). RESULTS: Numerous differences were noted between cases and controls with disease activity measures. All median values of sex steroid hormones were within the range of normal for pSS cases. Positive correlations were noted between testosterone and ESR (r = 0.36, p = 0.03), testosterone and serum protein (r = 0.37, p = 0.05), and testosterone and focus score (r = 0.44, p = 0.007). Negative correlations were present between SHBG and anti-SSA (r = -0.33, p = 0.05), SHBG and anti-SSB (r = -0.43, p = 0.009), and DHT and CRP (r = -0.41, p = 0.05). No correlations were noted between estrogens and measures of pSS disease activity. CONCLUSION: Higher levels of disease activity (ESR, serum protein, and focus score) were associated with higher concentrations of testosterone. No correlation between disease activity and estrogens was found.

Androstenedione↗
PubMed2002

Risk factors for positive minor salivary gland biopsy findings in Sjögren's syndrome and dry mouth patients.

OBJECTIVE: To investigate risk factors for positive minor salivary gland biopsy results in Sjögren's syndrome (SS) and dry mouth patients. METHODS: A total of 289 patients with dry mouth symptoms were evaluated. Potential risk factors for positive minor salivary gland biopsy results (>1 focus of lymphocytes) were studied in 2 phases. In phase 1, predictor variable candidates were identified for the test study (phase 2). Odds ratios were calculated for predictor variables. RESULTS: IgG, IgA, keratoconjunctivitis sicca, and sex, identified as the best predictor variables from phase 1 data, were included in a logistic regression model using phase 2 data. Only IgG demonstrated association with biopsy results (chi(2) = 20.4, P = 0.0001). An elevated IgG level (>1,482 mg/dl) had a high specificity (97% and 97%), high positive predictive value (PPV) (97% and 97%), but poor sensitivity (40% and 45%) in predicting positive biopsy results and SS, respectively. CONCLUSION: Elevated serum IgG levels best predicted a positive biopsy result and SS with high PPV and specificities.

Adult↗