Lateral epicondylitis of the elbow: US findings

PURPOSE: To determine the sensitivity and specificity of ultrasonography (US) in the detection of lateral epicondylitis and identify the US findings that are most strongly associated with symptoms. MATERIALS AND METHODS: Internal review board approval was obtained for retrospective review of the patient images, and the need for informed consent was waived. Internal review board approval was also obtained for scanning the 10 volunteers, all of whom gave informed consent. The study was compliant with the Health Insurance Portability and Accountability Act. US of the common extensor tendon was performed in 20 elbows in 10 asymptomatic volunteers (six men, four women; age range, 22-38 years; mean age, 29.6 years) and 37 elbows in 22 patients with symptoms of lateral epicondylitis (10 men, 12 women; age range, 30-59 years; mean age, 46 years). Fifty-seven representative images, one from each elbow, were randomly assorted and interpreted by three independent readers who rated each common extensor tendon as normal or abnormal. Abnormal images were further classified as demonstrating one or more of eight US findings. Readers interpreted each image at two separate sessions to determine intrareader variability. The authors calculated the sensitivity and specificity of US in the diagnosis of lateral epicondylitis and the odds ratio for each US finding. Odds ratios were considered statistically significant at P < .05 when 95% confidence intervals did not include one. RESULTS: Sensitivities of US in the detection of symptomatic lateral epicondylitis ranged from 72% to 88% and specificities from 36% to 48.5%. Odds ratios for the following findings were statistically significant (P < .05) for both reading sessions: calcification of common extensor tendon, tendon thickening, adjacent bone irregularity, focal hypoechoic regions, and diffuse heterogeneity. Odds ratios for lateral epicondyle enthesophytes were statistically significant (P < .05) for the first reading session only. Odds ratios for linear intrasubstance tears and peritendinous fluid were not statistically significant. CONCLUSION: US of the common extensor tendon had high sensitivity but low specificity in the detection of symptomatic lateral epicondylitis. The relationship between symptoms and intratendinous calcification, tendon thickening, adjacent bone irregularity, focal hypoechoic regions, and diffuse heterogeneity was statistically significant.     

Potential impact of chemical prophylaxis on the incidence of gonorrhoea

This paper presents a stochastic statistical model to evaluate the potential impact on the incidence of gonorrhea of a prophylactic intravaginal compound. The model predicts the change in the national incidence of gonorrhea in the US at various hypothetical levels of effectiveness of the topical prophylactic and of population usage. Factors analyzed in calculating the expected number of cases of gonorrhea under different conditions included the average risk of an uninfected person acquiring gonorrhea during a generation (incubation + average time to next sex act), the overall rate of loss of infectiousness whether by treatment or spontaneous cure during a generation, the proportion of at risk individuals prevented from acquiring a gonococcal infection in a generation by a prophylactic compound, and the proportion of the population at risk using the compound before each act of coitus. This model indicates that, with no changes in venereal disease prevention and treatment programs, the number of cases of gonorrhea will increase by 17% from 577,486 in 1970 to 674,804 in 1971. However, if only 30% of the population at risk used a prophylactic product that is 70% effective, gonorrhea could be almost completely eliminated within 5 years. Even a 50% effective prohylactic used by only 25% of the at risk population could produce dramatic decreases in the incidence of gonorrhea in a short time. Prophylactic programs will be most effective if incorporated into existing treatment and education programs.     

SHORT-TERM RETENTION IN RELATION TO AROUSAL

During normal classroom instruction involving presentation of a traffic safety film, the apparent skin conductance of each of 83 high school students was recorded on a separate magnetic tape channel, for subsequent computer analysis. Retention of film information was tested by a written questionnaire immediately after the film. The regression of retention on arousal depended upon the type of analysis and the measure of arousal: inverted-U for interindividual analysis and arousal level, and inverse for intraindividual analysis and arousal increment. These results, significant at the. 01 level, suggest that differences in some previous results may reflect the type of analysis and measure of arousal employed.     

Host receptors: the key to establishing cells with broad viral tropism for vaccine production

Abstract

Cell culture-based vaccine technology is a flexible and convenient approach for vaccine production that requires adaptation of the vaccine strains to the new cells. Driven by the motivation to develop a broadly permissive cell line for infection with a wide range of viruses, we identified a set of the most relevant host receptors involved in viral attachment and entry. This identification was done through a review of different viral entry pathways and host cell lines, and in the context of the Baltimore classification of viruses. In addition, we indicated the potential technical problems and proposed some solutions regarding how to modify the host cell genome in order to meet industrial requirements for mass production of antiviral vaccines. Our work contributes to a finer understanding of the importance of breaking the host–virus recognition specificities for the possibility of creating a cell line feasible for the production of vaccines against a broad spectrum of viruses.     

A crossreactive antipeptide monoclonal antibody with specificity for lysyl-lysine

Synthetic peptides meeting certain guidelines have been used as immunogens to generate antibodies with predefined specificity. We have raised and characterized using established methods a monoclonal antibody against a synthetic peptide corresponding to the 18-amino acid carboxyterminal sequence (A194-211) of the platelet-derived growth factor (PDGF) A chain expressed by the U343 human glioma cell line. This antibody was generated in order to carry out structure-function studies on this region of PDGF whose biological significance is not yet clear. Anti-PDGF-A194-211 was found to be a low titre, IgMκ molecule, with K_{rmd of} 2.8 × 10⁻⁷M. When antibody reactivity was tested with parent PDGF-AA_L (A chain homodimer containing a carboxyterminal extension) significant binding was observed. Suprisingly, ¹²⁵I-PDGF-AA_S, consisting of truncated A chains but lacking the extension was also bound. Moreover, poly- -lysine, β-thromboglobulin, PDGF-A194-211, and myoglobin competed dose-dependently with ¹²⁵I-PDGF-AA_L for antibody, ¹²⁵I-bovine serum albumin was also bound. Examination of the primary sequence of proteins and peptides bound by the antibody revealed only one shared structural motif: a lysyl-lysine moiety. Selected small synthetic peptides containing this and other sequences were used as potential competitors of ¹²⁵I-PDGF-A194-211 in antibody binding. Lysyl-lysyl-glycyl-glutamine and lysyl-lysine competed, whereas lysyl-leucine did not. These results suggest that as few as two amino acid residues constitute a functional antigenic determinant and contrast with most previous estimates of the minimum number of residues required. Furthermore, we show that guidelines governing the design of synthetic peptides for their use as antigens to produce monoclonal antibodies of predetermined specificity may be unreliable.     

Recent developments in drug-eluting stents

Percutaneous coronary intervention (PCI) is an important treatment approach in the management of symptomatic coronary artery disease (CAD). A significant development in PCI in the mid 1970s was balloon angioplasty, followed by bare-metal stents a decade later, and now, the widespread use of drug-eluting stents (DES). While PCI has conferred remarkable benefit to millions of CAD patients, restenosis, and late stent thrombosis associated with DES remain problematic, and improvements are keenly sought. This article reviews recent developments in DES.     

F-FDG-PET imaging in radiotherapy tumor volume delineation in treatment of head and neck cancer

Purpose

To determine the impact of ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) in radiotherapy target delineation and patient management for head and neck squamous cell carcinoma (HNSCC) compared to computed tomography (CT) alone.

Materials and methods

Twenty-nine patients with HNSCC were included. CT and PET/CT obtained for treatment planning purposes were reviewed respectively by a neuroradiologist and a nuclear medicine specialist who were blinded to the findings from each other. The attending radiation oncologist together with the neuroradiologist initially defined all gross tumor volume of the primary (GTVp) and the suspicious lymph nodes (GTVn) on CT. Subsequently, the same radiation oncologist and the nuclear medicine specialist defined the GTVp and GTVn on ¹⁸F-FDG-PET/CT. Upon disagreement between CT and ¹⁸F-FDG-PET on the status of a particular lymph node, an ultrasound-guided fine needle aspiration was performed. Volumes based on CT and ¹⁸F-FDG-PET were compared with a paired Student’s t-test.

Results

For the primary disease, four patients had previous diagnostic tonsillectomy and therefore, FDG uptake occurred in 25 patients. For these patients, GTVp contoured on ¹⁸F-FDG-PET (GTVp-PET) were smaller than the GTVp contoured on CT (GTVp-CT) in 80% of the cases, leading to a statistically significant volume difference (p = 0.001). Of the 60 lymph nodes suspicious on PET, 55 were also detected on CT. No volume change was observed (p = 0.08). Ten biopsies were performed for lymph nodes that were discordant between modalities and all were of benign histology. Distant metastases were found in two patients and one had a newly diagnosed lung adenocarcinoma.

Conclusions

GTVp-CT was significantly larger when compared to GTVp-PET. No such change was observed for the lymph nodes. ¹⁸F-FDG-PET modified treatment management in three patients, including two for which no curative radiotherapy was attempted. Larger multicenter studies are needed to ascertain whether combined ¹⁸F-FDG-PET/CT in target delineation can influence the main clinical outcomes.