Deborah V. Dawson

Meta-analysis of measures of sexual activity and prostate cancer.

We conducted a meta-analysis of the association between prostate cancer and aspects of sexual activity. The data suggest an elevated relative risk (RR) of prostate cancer among men with a history of sexually transmitted infections. This was observed with both random- and fixed-effects models (RR = 1.4; 95% CI = 1.2–1.7; N = 17 studies; heterogeneity P = 0.14), especially for syphilis (RR = 2.3; 95% CI = 1.3–3.9; N = 6; heterogeneity P = 0.47). Risk of prostate cancer is also associated with increasing frequency of sexual activity (RR = 1.2 for an increase of three times per week; 95% CI = 1.1–1.3; N = 12). However, these studies are heterogeneous (P < 0.001). Increasing number of sexual partners is also associated with prostate cancer (RR = 1.2 for an increase of 20 partners; 95% CI = 1.1–1.3; N = 16; heterogeneity P = 0.11). The data do not support associations with multiple marriages, age at first intercourse, or age at first marriage. These results indicate an association between prostate cancer and sexually transmitted infections, suggesting that infections may represent one mechanism through which prostate cancer develops. The mechanism through which frequency of sexual activity may be related to prostate cancer is unclear.

Effects of public and professional education on reducing the delay in presentation and referral of stroke patients.

Background and Purpose Several emerging stroke therapies require patients to be treated within several hours of symptom onset. Past studies have documented a significant delay between symptom onset and hospital presentation. As part of an experimental treatment study using tissue-type plasminogen activator, we began a multifaceted program of public and professional education to reduce the delay in presentation and referral of acute stroke patients. Methods The educational efforts focused on improving the recognition of stroke symptoms, the study enrollment criteria, and the need for rapid treatment of stroke patients. This program included 1) interviews on television and radio, 2) newspaper articles, 3) lectures to local and regional primary care and emergency department physicians, 4) mailings to several thousand local physicians, 5) having neurologists on-call for referrals 24 hrs/day, and 6) use of the Duke Life-Flight helicopter. Results Since starting our program, 139 of 159 (86%) patients with cerebral infarction presented primarily to or were referred to our facility within 24 hours of symptom onset, compared with 70 of 187 37%) before our educational efforts (p < 0.00001). No significant change was seen in patients with intracerebral hemorrhage (23 of 30 [77%] within 24 hours after program, compared with 25 of 40 [63%] before educational efforts; p = 0.30). Conclusions These findings suggest that educational efforts aimed at the public and health professionals may increase recognition of stroke symptoms and reduce the delay in presentation and referral of stroke patients.

Thematic Review Series: Skin Lipids. Antimicrobial lipids at the skin surface

The skin surface represents our interface with the external environment, and as such, is our first line of defense against microbial colonization and infection. Lipids at the skin surface are thought to underlie at least part of an antimicrobial barrier. Some of these lipids are synthesized in the epidermis and are carried to the surface as cells differentiate, whereas others are secreted onto the surface from the sebaceous glands. One such group, free sphingoid bases, are known to have broad antimicrobial activity, and our previous studies demonstrate their presence at the skin surface. Free sphingoid bases may be generated by enzymatic hydrolysis of epidermal ceramides. In addition, our preliminary results demonstrate potent antibacterial activity associated with two specific fatty acids derived from sebaceous triglycerides. Most remarkably, one of these fatty acids (sapienic acid, C16:1Δ6), in combination with a low concentration of ethanol, is very effective against methicillin-resistant Staphylococcus aureus (MRSA). In fact, this combination was far more effective than mupirocin with or without ethanol. Mupirocin is a “gold standard” for activity against MRSA.

Genetic linkage studies in Alzheimer's disease families

Alzheimers disease is a devastating neurological disorder and the leading cause of dementia among the elderly. Recent studies have localized the gene for familial Alzheimers disease to chromosome 21 in a series of early onset AD families (mean age of onset less than 60). Familial late onset AD (mean age of onset greater than 60) is a more common clinical form of the disorder. Thirteen families with multiply affected Alzheimers disease family members were identified and sampled. Ten of these families were of the late onset Alzheimers disease type. Simulation studies were used to evaluate the usefulness of these pedigrees in linkage studies in familial Alzheimers disease. Linkage studies undertaken to test the localization of both early onset and late onset Alzheimers disease families to chromosome 21 failed to establish linkage and excluded linkage from a large portion of the region where the early onset Alzheimers disease gene was localized. These findings suggest that more than one etiology may exist for familial Alzheimers disease and indicate the need for continued screening of the genome in familial Alzheimers disease families.

Swallowing in Alzheimer's disease

SummaryUsing a prospective case series design, we examined the incidence of oropharyngeal swallowing abnormalities in 25 patients with moderate or severe Alzheimers disease by videofluoroscopy. Aspiration occurred in 6 of 25 (28.6%). Only four patients showed unequivocally normal performance. Exploratory statistical analyses showed that swallowing abnormalities associated significantly with duration of dementia, eating dependency, and abnormal oral praxis. We observed a trend toward a higher incidence of aspiration in patients with more severe dementia. We conclude that oropharyngeal swallowing abnormalities, including aspiration, are more prevalent in patients with Alzheimers disease than in normal elderly individuals.

Predictors of outcome of epilepsy surgery: multivariate analysis with validation.

Summary: Purpose: To identify predictors of outcome of epilepsy surgery, using the Duke experience, applying multivariate analysis and validation techniques. To compare the results of different modeling algorithms. Few previous studies have reported multivariate analysis, or validated their results.

Hereditary motor and sensory neuropathy, X‐linked A half century follow‐up

The existence of an X-linked sensorimotor peripheral neuropathy has been debated. We reevaluated the original family, and present data on 13 affected males and 25 obligate or probable heterozygous females, documenting the devastating nature of the disease in the men and the extremely variable degree of clinical involvement in the carriers. Use of DNA probes indicates that the gene lies in the DXYS1-p58-1 region of the X-chromosome.

Temporal lobectomy and independent bitemporal interictal activity: what degree of lateralization is sufficient?

Summary: We attempted to determine whether the degree of lateralization of independent bitemporal interictal spikes and sharp waves (ISSW) is correlated with good results after temporal lobectomy. Three observers independently counted ISSW in the scalp EEGs of 59 candidates for temporal lobectomy to determine the degree of lateralization of ISSW. Interobserver correlation in percentage of lateralization was excellent (r= 0.92). Thirty‐one candidates were also evaluated with depth EEG (DEEG). Operative success was graded by the number of seizures reported in the second postoperative year. There was a significant progressive decrease in the number of good operative results as the degree of lateralization of ISSW lessened (p = 0.0142). Ninety‐two percent of patients with >90% lateralization had a good surgical outcome, whereas only 50% with <90% lateralization had a good outcome. Even when all DEEG‐recorded seizures emerged from the side of the lobectomy, patients with >90% lateralization appeared to have better outcomes than patients with <90% lateralization. We conclude that >90% lateralization of temporal ISSW is associated with good surgical outcome, and DEEG may not be necessary in these patients. Less than 90% lateralization is associated with poor surgical outcome and the additional information provided by DEEG may be especially useful in such patients.

A longitudinal study of dental caries risk among very young low SES children.

OBJECTIVES Early childhood caries (ECC) is a challenging public health problem in the United States and elsewhere; however, there is limited information concerning risk factors in very young children. The purpose of this study was to assess baseline risk factors for 18-month caries prevalence as part of a longitudinal study of high-risk children. METHODS About 212 children, 6-24 months of age were recruited from a rural community in Iowa. Subjects were enrolled in the WIC program, which provides nutritional support for low-income families with children. Dental examinations using d1, d2-3 criteria were conducted at baseline and after 18 months. Caries prevalence was determined at the frank decay level (d2-3 or filled surfaces), as well as at the noncavitated level (d1), and combined (d1, d2-3 or f surfaces). Risk factor data were collected at baseline and after 9- and 18- months. These data included beverage consumption data, presence of visible plaque, and use of fluoride toothpaste for children as well as mutans streptococci (MS) levels of mothers and children and family sociodemographic factors. RESULTS About 128 children (60%) remained in the study after 18 months. Among these children, prevalence of d1,d2-3/f level caries increased from 9% to 77%, while d2-3/f level caries increased from 2% to 20%. Logistic regression models for baseline predictors of d2-3f caries at the 18-month follow-up found the presence of MS in children (OR=4.4; 95% CI: 1.4, 13.9) and sugar-sweetened beverages (OR=3.0; 95% CI: 1.1, 8.6) to be the only significant risk factors. Sociodemographic factors and the use of fluoride toothpaste were not significant in these models. CONCLUSIONS Results suggest that early colonization by MS and consumption of sugar-sweetened beverages are significant predictors of ECC in high-risk populations.

Effect of Alveolar Ridge Preservation after Tooth Extraction A Systematic Review and Meta-analysis

Alveolar ridge preservation strategies are indicated to minimize the loss of ridge volume that typically follows tooth extraction. The aim of this systematic review was to determine the effect that socket filling with a bone grafting material has on the prevention of postextraction alveolar ridge volume loss as compared with tooth extraction alone in nonmolar teeth. Five electronic databases were searched to identify randomized clinical trials that fulfilled the eligibility criteria. Literature screening and article selection were conducted by 3 independent reviewers, while data extraction was performed by 2 independent reviewers. Outcome measures were mean horizontal ridge changes (buccolingual) and vertical ridge changes (midbuccal, midlingual, mesial, and distal). The influence of several variables of interest (i.e., flap elevation, membrane usage, and type of bone substitute employed) on the outcomes of ridge preservation therapy was explored via subgroup analyses. We found that alveolar ridge preservation is effective in limiting physiologic ridge reduction as compared with tooth extraction alone. The clinical magnitude of the effect was 1.89 mm (95% confidence interval [CI]: 1.41, 2.36; p < .001) in terms of buccolingual width, 2.07 mm (95% CI: 1.03, 3.12; p < .001) for midbuccal height, 1.18 mm (95% CI: 0.17, 2.19; p = .022) for midlingual height, 0.48 mm (95% CI: 0.18, 0.79; p = .002) for mesial height, and 0.24 mm (95% CI: –0.05, 0.53; p = .102) for distal height changes. Subgroup analyses revealed that flap elevation, the usage of a membrane, and the application of a xenograft or an allograft are associated with superior outcomes, particularly on midbuccal and midlingual height preservation.