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J D Beck

Publications and source records attributed to J D Beck.

At least 127 records · Page 7Linked to original sources
PubMed1992

[Hickman catheter for long-term parenteral therapy. A prospective interdisciplinary study].

160 patients with a median age of 38 years (range two months to 84 years) having silicone rubber central venous access catheters for long-term parenteral nutrition or chemotherapy were studied prospectively. Two different types of catheters were used, the Broviac-type "life-cath" and the Groshong -catheter. Intraoperative complications were not noticed. Parenteral therapy was performed in 124 patients (81%) without any complications. After a mean postoperative interval of 36 weeks there were 34 catheters removed because of end of therapy. 78 patients died with the catheter in place. 40 catheters had to be removed before end of therapy due to catheter-related complications. Occlusion of the lumen occurred in nine patients after an interval from three to 20 weeks. Explantation of catheters due to a suspected catheter-related sepsis was performed in 17 patients. Both types of catheter showed a high cumulative patency rate of 90% after a twelve months period. However, there were catheters that had to be removed before planned end of therapy. Thus, the cumulative rate of functioning catheters is lower (44% of all catheters).

Adolescent↗
PubMed1992

University of North Carolina Caries Risk Assessment Study: comparisons of high risk prediction, any risk prediction, and any risk etiologic models.

The purpose of this analysis is to compare three different statistical models for predicting children likely to be at risk of developing dental caries over a 3-yr period. Data are based on 4117 children who participated in the University of North Carolina Caries Risk Assessment Study, a longitudinal study conducted in the Aiken, South Carolina, and Portland, Maine areas. The three models differed with respect to either the types of variables included or the definition of disease outcome. The two "Prediction" models included both risk factor variables thought to cause dental caries and indicator variables that are associated with dental caries, but are not thought to be causal for the disease. The "Etiologic" model included only etiologic factors as variables. A dichotomous outcome measure--none or any 3-yr increment, was used in the "Any Risk Etiologic model" and the "Any Risk Prediction Model". Another outcome, based on a gradient measure of disease, was used in the "High Risk Prediction Model". The variables that are significant in these models vary across grades and sites, but are more consistent among the Etiologic model than the Predictor models. However, among the three sets of models, the Any Risk Prediction Models have the highest sensitivity and positive predictive values, whereas the High Risk Prediction Models have the highest specificity and negative predictive values. Considerations in determining model preference are discussed.

Child↗
PubMed1992

The University of North Carolina caries risk assessment study: caries increments of misclassified children.

The University of North Carolina caries risk assessment was conducted between 1986 and 1989 with 5000 children initially in grades 1 and 5 from low fluoride sites in South Carolina and Maine. Clinical, microbiologic, behavioral, and demographic factors served as independent variables used in logistic multiple regression models to determine the predicted caries risk classification of each child. The 3-yr DMFS increment of each child was the dependent variable, and the 20-25% of those in each cohort with the highest increment were considered the high risk group. Sensitivity and specificity values averaged 0.60 and 0.83 respectively, indicating the misclassification of substantial numbers of children. This paper reports analysis of the DMFS increments of the misclassified children. The majority of children had DMFS increments within one or two surfaces of the classification cut points. Many false negative children had increments composed entirely of filled surfaces, often of minimal extent and without evidence of previous decay. Many false positive children had increments composed of decayed surfaces and would have benefitted from being identified as high risk and assigned to a preventive program. Other false positive children had sealants placed after the baseline examination that undoubtedly reduced their true increment. It is concluded that the consequences of misclassification are not serious for most children in this study.

Child↗
PubMed1992

Root caries prevalence in black and white North Carolina adults over age 65.

The baseline root caries prevalence of 809 dentate black and white home-dwelling North Carolinians over age 65 was determined along with the collection of a large number of demographic and behavioral, clinical, and microbiological variables in the longitudinal Piedmont over-age-65 Dental Study. In comparison to other studies of older adults, the prevalence of decayed-filled root surfaces (DFRS) was low, fewer than 2.0 DFRS in whites, and significantly fewer than that in blacks (1.3 DFRS). Although tooth loss was a substantial problem, nearly half of the white population and almost two-thirds of the black participants exhibited no evidence of root caries history. Even though DFRS prevalence was much lower in blacks, their treatment need for decayed root surfaces (DRS) was significantly higher than for white participants. Correlates with DRS within both race groups appeared to be those that reflect lack of access to dental services or neglect of oral health--decayed coronal surfaces, higher rates of tooth extraction, high CPITN scores and worst loss of attachment greater than or equal to 7 mm, and more than a year since the last dental visit. Some variables were associated significantly with one racial group, but not the other, while others, particularly root surfaces at risk and age, were not associated significantly with DRS. We concluded that although there was considerable neglect of root caries, particularly among blacks, it was not a serious problem among older North Carolinians.

Aged↗
PubMed1992

Statistical methodologies useful for the analysis of data from risk-assessment studies.

In dentistry, the vast majority of studies attempting to predict who is at high risk for getting a disease or condition, or attempting to identify risk factors for a specific disease or condition, have focused either on only one risk factor at a time, or have measured multiple potential risk factors, but analyzed their effects in isolation. Since researchers tend to agree that most dental conditions have a multiple etiology, it is necessary to develop models that consider simultaneously the effect of a number of potential risk factors on the disease or condition of interest if we are to have any understanding of the relative impact of potential risk factors. Many existing statistical techniques will aid dental researchers in identifying risk factors. However, the selection of an appropriate analytic technique depends on a number of conditions. The strategy for this paper is to discuss a wide range of possible statistical techniques that may be applied to the problem of deriving a model for identification of multiple risk factors for dental diseases and conditions. We have approached this task by presenting a number of dental research problems needing an appropriate analytic technique. Next, basic issues that must be considered in choosing an appropriate analytic strategy are discussed. These issues include features of the study design, the data structure of the variables being measured, and the types of assumptions that are applicable to provide valid inferences about the target population of interest. A matrix of possible analytic techniques is presented for various combinations of study-design and data-structure features. After a discussion of each of the techniques, the appropriate statistical techniques for each of the dental examples are described. The issues and examples presented in this paper should be of use to dental researchers who wish to investigate multiple risk factors for a disease or condition of interest.

Disease Susceptibility↗
PubMed1992

Models for coronal caries and root fragments in an elderly population.

A random sample of 809 dentate, home-dwelling people 65 years of age or older participated in a study to determine the prevalence of dental diseases in the elderly. Part of the study investigated the determinants of coronal caries and root fragments in these older adults. Using a wide array of potentially explanatory variables available, logistic regression models were developed to identify relationships between these variables and coronal caries and root fragments. The variables with the most explanatory power in the coronal caries model were the presence of decayed root surfaces, lower salivary flow rate, lack of regular dental care and an interaction variable including race and a perception of financial well-being. When a subsequent model was created that did not include decayed root surfaces or root fragments as potential explanatory variables, an additional variable relating to self-perception of mouth appearance emerged. The strongest variables in the model for root fragments were episodic (vs. regular) dental visits, presence of root caries, lack of replacement for lost teeth, high levels of Streptococcus mutans and number of teeth present in the mouth.

Black or African American↗
PubMed1992

Evaluation of oral bacteria as risk indicators for periodontitis in older adults.

The prevalence of people and sites with attachment loss, pocket depth, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis are described for a random sample of 366 black and 297 white community-dwelling adults, aged 65 or over, residing in five counties in North Carolina. In addition, relationships between sites harboring these microorganisms and loss of attachment (LA) and pocket depth (PD) are presented in a manner that considers the lack of independence of sites within each person. Pocket depths and recession were measured on all teeth by trained examiners during household visits. Immunofluorescent assays for A. actinomycetecomitans, P. intermedia, and P. gingivalis were conducted on subgingival plaque samples obtained from the mesiobuccal aspect of the four first molar teeth using paper points. The prevalences of A. actinomycetemcomitans, P. intermedia, and P. gingivalis were greater in blacks than in whites. The most striking difference was seen for P. gingivalis, which was found in 38.8% of blacks and 9.4% of whites. Similar relationships were found when the percent of sites with these organisms were assessed. Blacks with P. gingivalis or P. intermedia had a higher prevalence of sites with LA greater than or equal to 7 mm as compared to blacks not infected with P. gingivalis or P. intermedia. The same was true for whites. Similar relationships between P. gingivalis or P. intermedia and PD greater than or equal to 6 mm were found for both blacks and whites.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

[Prognostic factors and results after the combined surgical and radiotherapy treatment of ependymomas].

Between 1978 and 1991, 31 patients with primary (n = 28) and recurrent (n = 3) ependymoma received external radiation after initial surgery. There were 26 cases of intracranial and five cases of spinal ependymoma. Histological grading revealed low-grade in 23 and high-grade tumors in eight patients. Craniospinal irradiation was given to 13 of 28 patients, whole cranial radiation with boost to posterior fossa in three and local treatment to twelve patients. Six of 28 patients received chemotherapy. Dose to the primary, tumor localisation, grading and extend of surgery did not significantly impact on survival and relapse-free survival. Age was a marginally significant prognostic factor for survival. In patients with intracranial ependymoma (n = 24) survival and relapse-free survival at five years were 54% and 42%, respectively. Patterns of recurrence showed a local recurrence alone in eight, a CNS-relapse with local recurrence in four and local recurrence with distant metastases in one case. Spinal seeding occurred in two of 13 after craniospinal irradiation and two of twelve patients after local treatment. The main problem in the treatment of ependymoma remains local control, the use of spinal irradiation does not seem to improve treatment results.

Adolescent↗
PubMed1992

Epidemiology of nondental oral disease in the elderly.

This article presents the descriptive epidemiology, risk factors, and clinical highlights of the oral mucosal lesions that are most common or of greatest concern among the elderly. Leukoplakia, oral cancer, candidiasis, lichen planus, and RAU have not been studied extensively among the elderly. Recent efforts to standardize definitions and research methods should greatly enhance future information. The paucity of research on oral lesions such as herpes zoster, epulis, and oral medication reactions is surprising, given that these are common problems among the elderly.

Aged↗
PubMed1992

[Tumors of the adrenal gland and lumbar sympathetic chain. Differential ultrasound diagnosis in childhood].

In a retrospective study from 1979 to 1989 17 tumors of the sympathic chain and the adrenal gland were analysed according to typical sonographic patterns. 13 tumors (10 neuroblastomas, 2 pheochromocytomas, 1 adenoma of the adrenal gland) were localized within the abdomen, 4 tumors (3 neuroblastomas, 1 ganglioneuroma) originated from the mediastinum. Neuroblastomas usually were great suprarenal masses with bad delineation and inhomogenous increased echogenicity in comparison with the liver. In more than 50% calcifications occurred, whereas cysts (15%) could rarely be found. The upper pole of the ipsilateral kidney usually was compressed and displaced caudally and laterally. The great intraabdominal vessels were usually displaced anteriorly and to the opposite side. The disturbed flow within the compressed intraabdominal vessels could reliably be shown by colour Doppler sonography as well as tumor vascularity. The 2 pheochromocytomas as well as the ganglioneuroma and the adenoma of the adrenal gland were round or oval, well delineated nodules with homogeneous liver like echogenicity. According to their typical sonographic patterns tumors of adrenal gland and sympathic chain can be differentiated from each other as well as from kidney tumors.

Abdominal Neoplasms↗
PubMed1991

Dental treatment needs in an elderly population.

A random sample of 1,019 adults 65 years of age and older, living in their own homes, consented to a clinical dental examination and an interview. Eight hundred nine subjects were dentate and 210 were edentulous. Each dentate person was examined for caries and periodontal conditions, as well as a separate determination of restorative and extraction treatment needs. Most people in this study lacked restorative treatment needs of any kind. Blacks required restorative treatment and extractions more often than whites. Carious coronal and root surfaces, pocket depths, number of teeth, as well as educational level and time since last visit to the dentist were related to treatment needs. While clinical findings were related to treatment needs, precise determinations of treatment needs of this elderly population generally could not be based solely on clinical findings. Additional behavioral, social, and health factors appear to play a role in dentists' decisions when determining treatment needs of older persons.

Black or African American↗
PubMed1991

Epidemiology of oral diseases.

Recent epidemiologic findings for coronal and root surface caries, enamel fluorosis, and the periodontal diseases are reviewed. Incidences of coronal caries in children have continued to decline (at an accelerated rate in some populations) during the 1980s. Two possible reasons other than fluorides for these trends are a change in providers' criteria for treatment of pit and fissure caries and the use of dental sealants. Further declines are anticipated, particularly if benefits resulting from preventive programs can be extended to lower socioeconomic groups. The study of root caries has evolved to include concerns of standardized measurement, documentation of incidence in addition to prevalence, and use of multivariate analyses to identify potential explanatory variables. Evidence supports an increase in the prevalence of enamel fluorosis, generally of the milder forms; use of fluoride supplements and toothpastes at an early age may be risk factors for this condition. The prevalence of severe periodontal disease in the general population is low. Initial assessments of risks for periodontal disease progression have identified a number of potential factors that are related to the diseases in a complex way. Significant analytic advances have been made to aid in risk-factor identification.

Child↗
PubMed1991

[Impulse cytophotometry determination of the DNA content of paraffin-fixed neuroblastoma].

The aim of the study was to develop a method to obtain a single cell suspension from paraffin fixated neuroblastoma tissue for measuring the DNA content by flow cytometry, and to detect possible correlation between the histological grading and the DNA stemline, and to relate these findings to the patients' prognosis. 51 samples of the fixated neuroblastoma tissue were measured. It was possible to determine the DNA content in 38 probes of the material. 79% of the evaluated samples showed aneuploid DNA stemlines, 21% showed euploid stemlines. Despite the small number of probes it was found, that in relation to the histological grading of neuroblastoma a lower grade of malignancy correlated with an euploid DNA content and a higher grade of malignancy correlated with an aneuploid DNA content. A correlation between DNA stemlines and the patients' prognosis was not found.

Adolescent↗
PubMed1990

The changing incidence of cervical intra-epithelial neoplasia.

In order to determine whether the incidence of cervical intraepithelial neoplasia (CIN) was changing, statistics were obtained from the annual reports of the cytopathology laboratory at Groote Schuur Hospital, Cape Town, for the years 1979-1988 inclusive, and from the computerised records of the laboratory during 1987 and 1988. Analysis of 642,574 smears during the 10-year period showed an increase in incidence of human papillomavirus infection was noted. The follow-up of patients with CIN 3 was good. The peak incidence of CIN was in the 29-39 year age group. A high pick-up rate of CIN was noted in pregnant patients--10% had CIN 3. Smears from teenage patients, 78% of whom were pregnant, showed an alarmingly high incidence of atypical findings. The incidence of CIN is also high in the geriatric group of patients. These findings indicate that traditional teaching concerning cervical intra-epithelial neoplasia needs to be reviewed.

Adolescent↗
PubMed1990

[Venous long-term indwelling catheter and port systems in children. Progress in pediatric oncology].

Long-term indwelling catheters of the Broviac, Hickman, Groshong type, and the Port Systems have proved highly suitable as a supportive measure in pediatric oncology. They are indicated for cytostasis, bone marrow transplantation and long-term parenteral nutrition. They provide reliable and safe venous access for therapy and blood sampling. Therapy is thus faciliated, and the quality of the patient's life is significantly improved by reducing the number of venipunctures required.

Blood Specimen Collection↗
PubMed1990

The prevalence of periodontal attachment loss in an Iowa population aged 70 and older.

Survey dental examinations were conducted in 262 dentate elderly people aged 70 and older and residing in two rural Iowa counties. Over 60 percent of the elderly in these countries were dentate. Buccal and mesial sites of all teeth were assessed for gingival recession, pocket depth, and attachment loss. Mean loss of periodontal attachment was 2.1 mm, and was slightly greater in older age groups and in men. More gingival recession was found on buccal sites and deeper pocketing was found on mesial sites regardless of age group, sex, or tooth type. However, the clinical magnitude of these differences was small. The prevalence of advanced periodontal breakdown was relatively low, with less than 15 percent of the subjects having at least one site with attachment loss of 7 mm or more. However, moderate periodontal breakdown was highly prevalent in this older population.

Aged↗
PubMed1990

Prevalence and risk indicators for periodontal attachment loss in a population of older community-dwelling blacks and whites.

The extent and severity of periodontal attachment loss are described for a random sample of 690 dentate community-dwelling adults, aged 65 or over, residing in five counties in North Carolina. In addition, risk indicators for serious levels of loss of attachment and pocket depth in this population are presented. Pocket depths and recession were measured on all teeth by trained examines during household visits. Blacks had an average of 78% of their sites with attachment loss and the average level of loss in those sites was approximately 4 mm, as compared to 65% and 3.1 min for whites. Because the extent and severity scores in this population were much higher than in younger groups, a serious condition in this group was defined as having 4+ sites of loss of attachment of 5+ mm with one or more of those sites having a pocket of 4+ mm. Bivariate analyses identified a large number of explanatory variables that were associated with increased likelihood of having the more serious periodontal condition. The logistic regression model for blacks includes the following important explanatory variables and associated odds ratios: use to tobacco (2.9), colony counts of B. gingivalis greater than 2% (2.4) and B. intermedius greater than 2% (1.9), last visit to the dentist greater than 3 years (2.3), and gums bleeding in the last 2 weeks (3.9). The model for whites indicated that tobacco use (6.2), presence of B. gingivalis (2.4) and the combined variable of having not been to the dentist in the last 3 years and having a high BANA score (16.8) were important explanatory variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Black or African American↗