G1 checkpoint protein and p53 abnormalities occur in most invasive transitional cell carcinomas of the urinary bladder.

The G1 cell cycle checkpoint regulates entry into S phase for normal cells. Components of the G1 checkpoint, including retinoblastoma (Rb) protein, cyclin D1 and p16INK4a, are commonly altered in human malignancies, abrogating cell cycle control. Using immunohistochemistry, we examined 79 invasive transitional cell carcinomas of the urinary bladder treated by cystectomy, for loss of Rb or p16INK4a protein and for cyclin D1 overexpression. As p53 is also involved in cell cycle control, its expression was studied as well. Rb protein loss occurred in 23/79 cases (29%); it was inversely correlated with loss of p16INK4a, which occurred in 15/79 cases (19%). One biphenotypic case, with Rb+p16- and Rb-p16+ areas, was identified as well. Cyclin D1 was overexpressed in 21/79 carcinomas (27%), all of which retained Rb protein. Fifty of 79 tumours (63%) showed aberrant accumulation of p53 protein; p53 staining did not correlate with Rb, p16INK4a, or cyclin D1 status. Overall, 70% of bladder carcinomas showed abnormalities in one or more of the intrinsic proteins of the G1 checkpoint (Rb, p16INK4a and cyclin D1). Only 15% of all bladder carcinomas (12/79) showed a normal phenotype for all four proteins. In a multivariate survival analysis, cyclin D1 overexpression was linked to less aggressive disease and relatively favourable outcome. In our series, Rb, p16INK4a and p53 status did not reach statistical significance as prognostic factors. In conclusion, G1 restriction point defects can be identified in the majority of bladder carcinomas. Our findings support the hypothesis that cyclin D1 and p16INK4a can cooperate to dysregulate the cell cycle, but that loss of Rb protein abolishes the G1 checkpoint completely, removing any selective advantage for cells that alter additional cell cycle proteins.

Periodontal bacteria in adult twins.

BACKGROUND: Both environmental and genetic factors are known to influence clinical measures of periodontal disease. The purpose of this study was to determine whether genetic factors similarly influence the presence of specific periodontal bacteria in subgingival plaque. METHODS: Reared-together and reared-apart monozygous (MZ) and dizygous (DZ) adult twins were examined clinically. Demographic and behavioral information was obtained from each subject by questionnaire. Subgingival plaque samples were obtained from the index teeth, and the presence of P. intermedia, P. gingivalis, A. actinomycetemcomitans, E. corrodens, and F. nucleatum was determined using an immunoassay. RESULTS: Microbiological and clinical data were available for 169 twin pairs. The subject-based prevalences of the bacteria in the twin groups ranged from 11% for Porphyromonas gingivalis to 40% for F. nucleatum. For all species examined, the concordance rates were not significantly different (P > 0.05) between MZ and DZ twin groups. These findings were apparent despite similar smoking histories, self-reported oral hygiene practices, and antibiotic use in the twin groups. Furthermore, MZ twins reared together were not more similar than MZ reared-apart twins with respect to any bacterial species examined. CONCLUSIONS: These findings suggest that in a population with access to routine dental care, any effects that host genes and the early family environment have on the presence of specific bacteria in subgingival plaque are not apparent in adulthood. Most twins with disease in this study had early periodontitis. Results from this study may not necessarily be extrapolated to more advanced disease states.

Clinical course of hypertrophic cardiomyopathy in a regional United States cohort.

CONTEXT: Hypertrophic cardiomyopathy (HCM) has been regarded as a disease that causes substantial disability, with annual mortality rates of up to 6%, based largely on reports from tertiary referral centers. OBJECTIVE: To assess the clinical course of HCM in a patient cohort more closely resembling the true disease state. DESIGN: Retrospective cohort study. SETTING: A regional cohort from Minnesota and adjoining regions, free of referral center bias, studied at Minneapolis Heart Institute. PATIENTS: Two hundred seventy-seven consecutively studied HCM patients, none referred for specialized HCM care, managed clinically in a standard fashion. MAIN OUTCOME MEASURES: Mortality and clinical course of HCM. RESULTS: During a mean (SD) follow-up of 8.1 (6.6) years, 45 patients died and 29 of these deaths were directly related to HCM; however, 8 of the 29 HCM deaths were not premature (occurring >75 years of age). Annual HCM mortality rate was 1.3% (0.7% for sudden cardiac death). Patients identified in adulthood (n = 234) showed no statistically significant difference in mortality when compared with expected mortality, as calculated for the general US or Minnesota populations (P=.17). Patients identified as children (n=43) showed decreased survival compared with the general population (P<.001). At most recent clinical evaluation, 192 patients (69%) had no or mild symptoms and 69 (25%) experienced incapacitating symptoms or HCM-related death; 53 (19%) of the patients had achieved estimated life expectancy of 75 years or older. More advanced symptoms at diagnosis-occurrence of atrial fibrillation (often associated with stroke), the presence of basal outflow obstruction of at least 30 mm Hg, and marked left ventricular wall thickness of more than 25 mm-were clinically important independent predictors of HCM mortality. CONCLUSIONS: In a regionally selected patient population most closely resembling the true disease state, HCM did not significantly increase the risk of premature death or adversely affect overall life expectancy. Prevailing misconceptions of HCM as a generally unfavorable condition may largely be related to the skewed patient referral patterns characteristic of tertiary care centers. Hypertrophic cardiomyopathy is nevertheless a highly complex disease capable of serious clinical consequences and premature death in some patients.

The impact of radiation on early breast carcinoma survival. A Bayesian analysis.

BACKGROUND: A Bayesian statistical approach was used to examine the effect of local control on survival of patients with early breast carcinoma. METHODS: The effect of radiation on overall survival was examined in the four published randomized trials on conservation surgery with or without radiation: the Uppsala-Orebro, Canadian, NSABP-B06, and Milan III trials. Classical and Bayesian statistical approaches were used to evaluate the effect of sample size and follow-up on the results. RESULTS: Combined 5-year survival results of patients with negative lymph nodes and surgical margins in the Uppsala-Orebro, Canadian, and NSABP-B06 trials indicated a 79% probability of a positive benefit with the addition of radiation and a 9.6% relative reduction in the annual mortality rate in favor of the irradiated patients. For the same subgroup of patients in the NSABP-B06 trial, the probability of a positive benefit with radiation increased from 65% at 5 years to 87% at 10 years, and is reflected in the change of the relative reduction in annual mortality from 8.2% at 5 years to 17.5% at 10 years. For all patients who accepted randomized treatment in the NSABP-B06 trial, the probability of a positive survival benefit with radiation was 80%, 98%, and 91% at 5, 10, and 12 years, respectively, with corresponding relative reductions in the annual mortality rates of 12.8%, 20.5%, and 15.2%. CONCLUSIONS: The addition of radiation to lumpectomy offers a small but important survival advantage, even in patients with negative surgical margins and lymph nodes. Because locoregional control and breast preservation are significantly improved with radiation, even a small survival advantage substantiates the importance of radiation in the treatment of patients with early breast carcinoma.

Crevicular fluid enzymes from endosseous dental implants and natural teeth.

Several neutrophil-derived enzymes that are present in the gingival crevicular fluid have been evaluated for use as risk markers for periodontal disease progression. However, very little information is available about the presence of these enzymes in peri-implant tissues. The purpose of this cross-sectional study was to compare levels of enzymes in gingival crevicular fluid between natural teeth and endosseous dental implants and between well-integrated and failing implants. Scores of plaque and gingivitis were recorded for 68 integrated implants, five failing implants, and 34 natural teeth in 12 completely edentulous and 18 partially edentulous subjects. Samples of gingival crevicular fluid were obtained from these sites using filter paper strips and were assayed for levels of neutral protease, neutrophil elastase, myeloperoxidase, and beta-glucuronidase. Neutral protease levels were higher (P = .066) at moderately to severely inflamed implant sites (Gingival Index of 2, 3) compared to mildly or noninflamed sites (Gingival Index of = 0, 1). Despite the small number (n = 5) of failing implants evaluated in this study, levels of neutrophil elastase, myeloperoxidase, and beta-glucuronidase were significantly higher (P < or = .001) around failing implants compared to successful implants. Neutral protease levels were also elevated around failing implants, but the difference was not statistically significant. Results of this study indicate that neutrophil elastase, myeloperoxidase, and beta-glucuronidase levels in GCF appear to be good candidates for study as risk markers of implant failure.

Immunohistochemical staining for markers of future neoplastic progression in the larynx.

We performed a retrospective, longitudinal study to determine whether abnormalities in immunohistochemical staining for the epidermal growth factor receptor (EGFR), p53, or cyclin D1 occur before the development of laryngeal carcinoma. Staining was performed on 63 paraffin-embedded biopsies from 18 patients who subsequently developed carcinoma in situ (CIS) or invasive carcinoma of the larynx. These were compared to 71 biopsies from 20 patients who did not develop CIS/cancer (minimum follow-up period, 4 years). Also studied were the 34 biopsies containing CIS and/or carcinoma from those patients who progressed and 22 biopsies obtained concurrently. The two patient groups did not differ significantly in terms of tobacco and alcohol use. Distinct patterns of staining correlated with malignant progression. These included EGFR staining of two thirds or more of the epithelium thickness, a linear basal p53 staining pattern, and strong (3+) staining for cyclin D1 (P < 0.01 for each). These staining patterns also correlated with increasing atypia. In our study population, linear basal staining for p53 and strong staining for cyclin D1 had higher specificity for progression than did EGFR overexpression, which was also seen in association with inflammation and chronic irritation. Marked site-to-site variation was seen in the immunohistochemical staining and in the degree of atypia, suggesting that multiple biopsies are necessary to properly assess risk. These immunohistochemical staining patterns may be clinically useful to predict patients at risk for neoplastic progression.

Strontium-89 chloride (Metastron) for palliative treatment of bony metastases. The University of Minnesota experience.

Strontium-89 chloride (Metastron) is an FDA-approved treatment for palliation of cancer pain. We evaluated blood count changes and pain relief in 28 patients with widespread painful bony metastasis treated with strontium-89 at the University of Minnesota Hospital and Clinics. Eighteen patients had prostate cancer (all hormone-refractory cancer), seven patients had breast cancer, and three patients had lung cancer, all previously treated with either radiation, chemotherapy, or a combination of the two. Serial blood counts were performed weekly up to 8 weeks and at 12 weeks after administering Metastron. Pain scale and blood values were monitored simultaneously. The mean baselines of hemoglobin (Hgb), white blood count (WBC), and platelets (Plts) were 11.4, 5900, and 258,000, respectively. The mean dose of Metastron was 3 mCi (range 2.2-4.4). The median time (range) to nadir was about 6 weeks. The percentage reductions relative to baseline were 32% (range 0-72%) for WBC; 14% (range 0-50%) for Hgb; 15% (range 0-47%) for the red blood cell (RBC) count; and 40% (range 0-85%)for Plts. We did not find a close relationship among the baseline blood count, reduction of subsequent blood counts, or previously irradiated active bone marrow volume. The median time of survival was 23 weeks (range 2-66 weeks). At 12 weeks, 29% of patients had moderate to dramatic improvement of pain, 32% had some relief of pain, and 50% had no improvement in pain. Thirty-two percent of the treated patients required additional palliative external beam radiation to their bony lesions within the study period. Our results show that Metastron for palliation for bony metastases should be used with caution because of moderate to severe bone marrow toxicity, especially in platelets, associated with its use. Careful evaluation of patients given Metastron is needed to assess accurately its full benefit.

Neutrophil elastase in crevicular fluid: comparison of a middle-aged general population with healthy and periodontitis groups.

Neutrophil elastase (NE) was measured in crevicular fluid (GCF) collected from 3 subject groups. GCF was harvested at a single visit of subjects with periodontal health (n = 21) and with periodontitis (n = 28). Samples were obtained from 132 middle-aged, middle-class health conscious patients of a health maintenance organization (HMO) at baseline and 1 year later. GCF NE was higher in periodontitis than in health. Mean GCF NE of HMO subjects was much closer to health than to periodontitis. Few members of the HMO population had enzyme levels typical of periodontitis. Subjects and sites of the HMO population were segregated into 3 categories based on enzyme levels of the healthy and periodontitis subjects. Most HMO subjects and sites were in the activity category corresponding to healthy subjects. Only a small portion were in the activity category common in periodontitis. Enzyme levels in the highest activity category at both samplings were infrequent. High enzyme levels in the HMO population were not associated with attachment loss. Thus, assay of GCF NE provided little evidence of disease in a middle-aged, middle-class health conscious general population. This finding confirms an analysis of epidemiological surveys which concluded that a population such as studied here would not benefit from periodontal diagnostic testing.

The importance of local control in the conservative treatment of breast cancer.

The purpose of this study was to examine the meaning of local control, especially on survival, in breast cancer patients treated by lumpectomy with or without radiotherapy. We analyzed the survival results of four major published randomized trials that compare conservation surgery with or without radiation using three different statistical approaches: p-values, confidence intervals, and Bayesian techniques. All four trials report statistically significant increased local control and improved survival for the irradiated patients. Survival based on p-values and confidence intervals shows statistical significance for long-term follow-up of the NSABP-B06 trial, but not for the other trials, probably because of small sample sizes and short follow-up. At 10 years, the overall survival rates for the NSABP-B06 were 65% and 71% for lumpectomy alone or with radiation respectively. Interpreted in a Bayesian framework, the expected advantage in 10-year survival was 6% (the mean of NSABP-B06 10-year survival) with an 83% probability that the 10-year survival difference may lie between 2% and 10%. An 85% probability that 3% of patients will survive at 10 years because of irradiation translates into a 30% reduction in annual odds of death several years after treatment in stage I good prognosis patients and 15% in stage I poor prognosis patients. Analysis of the randomized trials comparing lumpectomy with or without radiation indicate a clear improvement in survival for the irradiated patients associated with increased local control. Combination of improved survival with the reduced psychological and economic costs associated with local recurrence argues well for the inclusion of radiation for many breast cancer patients.

Prevalence of periodontal pathogens with varying metabolic control of diabetes mellitus.

The purpose of this study was to determine the prevalence of 5 periodontal pathogens in individuals with diabetes mellitus. Subjects (n = 107) 20-70 years of age with type 1 (n = 60) or 2 (n = 47) diabetes mellitus were studied for the occurrence of the periodontal pathogens A. actinomycetemcomitans, F. nucleatum, E. corrodens, P. gingivalis and P. intermedia. Subgingival plaque was sampled in each subject from a single site exhibiting the greatest inflammation. The evaluation of selected periodontal bacterial pathogens was based on an immunoassay utilizing bacterial specific monoclonal antibodies. 35% of the sites harbored P. gingivalis, 28% F. nucleatum and 21% E. corrodens. A. actinomycetemcomitans and P. intermedia were found in less than 10% of the sites. Subjects for whom the probing depth at the sampled site was > or = 4 mm were more often found to have detectable pathogens than those with a probing depth < or = 3 mm. Diabetic factors such as duration, type and metabolic control of the disease had no statistically significant effect on the prevalence of these bacteria.

Expression of epidermal growth factor receptor in invasive transitional cell carcinoma of the urinary bladder. A multivariate survival analysis.

Epidermal growth factor receptor (EGFR) immunoreactivity was evaluated in 85 cases of invasive transitional cell carcinoma of the bladder. The impact of EGFR staining on patient survival was compared with tumor stage, histologic grade, immunoreactivity for c-erb B-2 and proliferating cell nuclear antigen, flow cytometrically determined S-phase fraction and DNA ploidy, abnormal expression of blood-group-related antigens, and patient blood type. Using a new monoclonal anti-EGFR antibody reactive in formalin-fixed tissue, the authors found a significant correlation between EGFR expression and high tumor stage, and between EGFR expression and poor patient outcome. However, EGFR expression as a predictor of prognosis was not independent of stage. An intriguing association between patient blood type and patient survival was noted. Other indices did not predict patient outcome after data were adjusted for stage.

Association between cigarette smoking, bacterial pathogens, and periodontal status.

The purposes of this study were to determine if: 1) an association exists between cigarette smoking and signs of periodontal disease after controlling for the confounding variables of age, sex, plaque, and calculus; 2) the prevalence of 5 bacteria commonly associated with periodontal disease differs between smokers and non-smokers; and 3) the presence of any of these bacteria or smoking are associated with a mean proximal posterior probing depth > or = 3.5 mm. Plaque, calculus, gingivitis, and probing depth were measured at the proximal surfaces of all teeth in one randomly selected posterior dental sextant in 615 adults. Subgingival plaque was sampled from the same sites and assayed for the presence of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum. A subsample of non-smokers (n = 126), who were similar to smokers (n = 63) with respect to age, sex, plaque, and calculus, was randomly drawn from the original sample. These two groups were then compared on the basis of clinical and microbial parameters. The results indicated that the odds of having a mean probing depth > or = 3.5 mm were 5 times greater for smokers than the non-smoker subsample (odds ratio = 5.3; 95% CI = 2.0 to 13.8). No statistically significant difference in the prevalence of any of the bacteria was found between smokers and the non-smoker subsample. Based on logistic regression analyses of each of the 5 bacteria and smoking, mean probing depth > or = 3.5 mm was significantly associated with the presence of A. actinomycetemcomitans, P. intermedia, E. corrodens, and smoking (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Natural distribution of 5 bacteria associated with periodontal disease.

The purpose of this study was to determine the prevalence and distribution of 5 bacterial pathogens in subgingival plaque, their relationship with each other and probing depth. Plaque was collected from 6905 sites in 938 subjects. A bacterial concentration fluorescence immunoassay and bacterial specific monoclonal antibodies were used to determine the presence and level of P. gingivalis (Pg), A. actinomycetemcomitans (Aa), P. intermedia (Pi), E. corrodens (Ec) and F. nucleatum (Fn) in each plaque sample. The prevalence in subjects was lowest for Pg (32%) and highest for Ec (49%). The site-based frequency distribution of these bacterial species ranged from 10.3% for Pg to 18.7% for Ec. Pi and Ec were the bacterial combination most often found together in a subject (27.2%). While 64.0% of the sites were without any of the 5 bacterial species evaluated, 20.2% had only 1 of the 5 bacterial species evaluated. The remaining 15.8% of sites had at least 2 bacteria species present. There was a general linear association of the detection level of bacterial species and probing depth. The odds ratios were 3.9 (Pg), 3.0 (Aa), 4.0 (Pi), 2.7 (Ec) and 2.8 (Fn) of finding high levels of these bacterial pathogens at > 5 mm probing depth (p < or = 0.01). Mean probing depth at molar sites without a specific bacteria was greater (p < or = 0.01) in subjects with a specific bacterium compared to molar sites in subjects without the bacteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Reliability of the evaluation of occlusal contacts in the intercuspal position.

Reliability of clinical measurement is essential to any clinical discipline. This investigation assessed intraexaminer and interexaminer reliability achieved in identifying contacting teeth in the intercuspal position. Shim stock and an articulating film were compared in the evaluation of occlusal contacts of 337 antagonist occlusal pairs in 24 young adults by two examiners. Results were compared by use of a simple proportion of agreement and, when possible, the Kappa statistical test that corrects for chance agreement. Shim stock displayed better reliability than articulating film and appeared suitable for clinical measurement of occlusal contacts in intercuspal position.

Influences on inferences. Effect of errors in data on statistical evaluation.

BACKGROUND: Inadvertent random and systemic errors introduced into data sets and manipulation of data are well-defined sources of discrepancies in statistical evaluation of clinical trials. In this study, the authors show the influence of errors on the widely used statistical result, P values. METHODS: Using data from a retrospective study of patients with Hodgkin disease treated at the University of Minnesota between 1970 and 1984 and observed to 1988, we introduced various errors into the data to study the impact on results. RESULTS: Inadvertent random and systemic errors affect statistical results. Data entry and transcription errors, vague definitions of endpoints and prognostic factors, and the omission and selection of patients are examples of frequent errors that affect statistical evaluation. CONCLUSION: The results and inferences of many studies are sensitive to systemic errors and data manipulation. Great care must be given to the clear definitions of terms, exclusion and inclusion criteria, group assignments, treatment protocols, and the subgroups on which statistical analysis is performed. Clinicians and statisticians must work together to improve the performance and interpretation of clinical trials.

Prevalence of periodontal disease in a health maintenance organization and comparisons to the national survey of oral health.

The purposes of this study were to: 1) characterize the demographics, oral health behavior, and periodontal status of a health maintenance organization sample; 2) investigate the relationship between the location of posterior proximal measurement sites and prevalence estimates for periodontal disease; and 3) compare the prevalence of persons with pockets > or = 4 mm in the present sample to the 1985 NIDR Survey of Oral Health. The sample consisted of 1,090 adults attending a large health maintenance organization. All proximal sites in one randomly selected posterior dental sextant were examined for probing depth using a constant force probe. Demographic, medical, and behavioral factors were determined by questionnaire. Results indicated that the sample consisted primarily of medically and periodontally-healthy middle-aged adults with good oral hygiene habits. Overall, the mean probing depth was 2.95 mm with 10.1% of sites/subject > or = 4 mm. A larger percent of subjects had probing depths with pockets > or = 4 mm at lingual proximal sites than buccal proximal sites. Prevalence of subjects with pockets > or = 4 mm at mesio-buccal sites in the present study was similar to NIDR Region III data (15.3% vs. 17.4% respectively). However, when data from all posterior sites were included, the overall prevalence rate in the present sample increased to 36.8%. These findings indicate that disease prevalence is dependent on the location of surfaces measured and conservatively indicate that NIDR survey data may have underestimated the prevalence of persons with periodontal pockets > or = 4 mm by at least 20%.

Effect of gels containing stannous fluoride on oral bacteria--an in vitro study.

The purposes of this investigation were to evaluate and compare the antimicrobial effect of (1) twelve 0.4 per cent stannous fluoride (SnF2) commercial products and (2) different concentrations of SnF2 (range = 0.02 to 3.28 per cent). The antibacterial inhibitory effect of various SnF2 gels was evaluated as to their effectiveness against oral plaque bacteria including strains of S. mutans, S. sanguis, S. sobrinus, A. viscosus, A. actinomycetemcomitans, and B. intermedius. When twelve different commercial preparations of 0.4 per cent SnF2 were compared for inhibitory effect on plaque bacteria, several of the SnF2 preparations were significantly more effective in inhibiting oral bacteria (p < 0.05). With increasing concentration of SnF2, there was a comparable increase in the inhibitory effect on the oral bacteria tested (r2 ranged from 0.867 to 0.996). SnF2 at a concentration of 0.4 per cent had a similar antibacterial effect to 0.12 per cent chlorhexidine. This in vitro study demonstrated that certain SnF2 products are highly effective in inhibiting the growth of bacteria often found in plaque, and this inhibitory effect is directly related to the concentration of the SnF2.

Lack of prognostic value of histopathologic parameters in Hodgkin's disease, nodular sclerosis type. A study of 123 patients with limited stage disease who had undergone laparotomy and were treated with radiation therapy.

The value of histopathologic parameters in predicting the long-term overall survival probabilities was studied in a series of 123 patients with pathologic stage IA, IB, IIA, IIB, or IIIA Hodgkin's disease, nodular sclerosis type who were treated with curative radiation therapy. The parameters that were studied included the relative proportion of atypical vs reactive cells, amount of eosinophils, presence of necrosis, degree of mitotic activity, intensity of different types of mesenchymal reactions, classification in three subtypes (ie, lymphocyte predominance, mixed cellularity, and lymphocyte depletion) or in two grades (ie, grades 1 and 2), and identification of the syncytial variant. For each parameter, the association with clinical risk factors was also analyzed. The results of this study show that there are no pathologic features that carry a significant predictive value of the overall survival.